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	claims	1. A collimator system comprising: a plurality of movable plates stacked one above another, said plates being constructed of a material substantially impervious to passage therethrough of radiation in a predetermined range of wavelengths; and at least one collimator aperture formed in each of said plates, wherein each of said plates is independently rotatable about a common axis. 2. The collimator system according to claim 1 wherein said plates are arranged relative to each other such that said collimator apertures formed in neighboring plates are alignable with each other to form a collimation path adapted for a radiation beam to pass therethrough. claim 1 3. The collimator system according to claim 1 wherein one of said collimator apertures on one of said plates has a different sized opening than a collimator aperture on another of said plates. claim 1 4. The collimator system according to claim 1 wherein at least one of said plates is formed with a plurality of differently sized collimator apertures. claim 1 5. The collimator system according to claim 1 wherein at least one of said plates is formed with a plurality of generally equally sized collimator apertures. claim 1 6. The collimator system according to claim 1 wherein a gap between neighboring plates of said plurality of movable plates is sufficiently small such that a radiation beam of a predetermined wavelength is substantially prevented from passing through said gap. claim 1 7. The collimator system according to claim 1 further comprising a controller connected to said plates which selectively revolves said plates. claim 1 8. The collimator system according to claim 7 wherein said controller comprises a servomotor linked to said plates which selectively revolves said plates. claim 7 9. The collimator system according to claim 1 wherein a subset of said plates are mechanically linked together and are mounted on bearings about a common axle, such that said subset of plates revolves together independently of the other plates. claim 1 10. The collimator system according to claim 1 further comprising a stop mechanism which selectively arrests movement of said plates. claim 1 11. A collimator system comprising: a plurality of movable plates stacked one above another, said plates being constructed of a material substantially impervious to passage therethrough of radiation in a predetermined range of wavelengths; and at least one collimator aperture formed in each of said plates, wherein at least one of said plates has a thickness different from another of said plates.
	claims	1. In an X-ray source that generates X-rays from a plasma produced by directing pulsed laser light onto a target material in a vacuum chamber evacuated to a subatmospheric pressure, a device for directing an X-ray flux from the plasma to a downstream optical system, comprising: an optical element situated such that X-rays from the plasma are incident on the optical element, the optical element having an axis of rotational symmetry and being configured to direct the X-ray flux to the downstream optical system; and a rotational actuator situated relative to the optical element and configured to rotate the optical element about the axis. 2. The device of claim 1 , wherein the optical element is an X-ray reflective mirror. claim 1 3. The device of claim 2 , wherein the mirror is selected from a group consisting of multi-layer mirrors, grazing-incidence mirrors, spherical mirrors, paraboloidal mirrors, planar mirrors, ellipsoidal mirrors, and a spherical mirrors. claim 2 4. The device of claim 2 , wherein the mirror comprises a reflective surface having a profile selected from a group consisting of spherical, paraboloidal, planar, ellipsoidal, a spherical, and combinations thereof. claim 2 5. The device of claim 1 , wherein the optical element is an optical filter or X-ray diffractive element. claim 1 6. The device of claim 1 , further comprising: claim 1 a position detector situated and configured to detect a position of the optical element; a controller to which the position detector is connected; and positional actuator connected to the controller and to which the optical element is mounted, the positional actuator being configured, when commanded by the controller, to move the optical element as required to maintain a desired position of the optical element, based on a signal from the position detector. 7. The device of claim 6 , wherein the positional actuator comprises an X-direction linear stage, a Y-direction linear stage, and a Z-direction linear stage. claim 6 8. The device of claim 6 , wherein the position detector comprises a contact-needle displacement gauge. claim 6 9. The device of claim 6 , wherein the position detector comprises a light source directed at the optical element and a light receiver oriented so as to receive light reflected from the optical element, the light source being selected from the group consisting of lasers, light-emitting diodes, and lamps. claim 6 10. The device of claim 1 , wherein the optical element is situated within the vacuum chamber. claim 1 11. An X-ray optical system including an X-ray source that generates X-rays from a plasma produced by directing pulsed laser light onto a target material in a vacuum chamber evacuated to a subatmospheric pressure, the X-ray optical system comprising a device as recited in claim 1 . claim 1 12. An X-ray source, comprising: a vacuum chamber; an X-ray generator situated within the vacuum chamber and configured to produce a plasma sufficiently energized so as to produce X-rays; an optical element contained in the vacuum chamber and situated such that X-rays from the plasma are incident on the optical element, the optical element having an axis of rotational symmetry and being configured to direct the X-ray flux in a downstream direction; and an actuating device situated relative to the optical element and configured to rotate the optical element about the axis. 13. The X-ray source of claim 12 , wherein the X-ray generator is a laser-plasma X-ray device. claim 12 14. The X-ray source of claim 12 , wherein the X-ray generator is a plasma-discharge X-ray device. claim 12 15. The X-ray source of claim 12 , wherein the optical element is an X-ray reflective mirror. claim 12 16. The X-ray source of claim 12 , wherein the optical element is an optical filter. claim 12 17. The X-ray source of claim 12 , further comprising: claim 12 a position detector situated and configured to detect a position of the optical element; a controller to which the position detector is connected; and a positional actuator connected to the controller and to which the optical element is mounted, the positional actuator being configured, when commanded by the controller, to move the optical element as required to maintain a desired position of the optical element, based on a signal from the position detector. 18. The X-ray source of claim 17 , wherein the positional actuator comprises an X-direction linear stage, a Y-direction linear stage, and a Z-direction linear stage. claim 17 19. The X-ray source of claim 17 , wherein the position detector comprises a contact-needle displacement gauge. claim 17 20. The X-ray source of claim 17 , wherein the position detector comprises a light source directed at the optical element and a light receiver oriented so as to receive light reflected from the optical element, the light source being selected from the group consisting of lasers, light-emitting diodes, and lamps. claim 17 21. An X-ray optical system, comprising an X-ray source as recited in claim 12 . claim 12 22. In a method for producing an X-ray flux, propagating along a propagation axis, from a plasma generated by exciting a target material, a method for producing an X-ray flux that remains axially symmetrical despite production of flying particles by the plasma, the method comprising: providing an optical element situated so as to direct the X-ray flux, propagating from the plasma, to a downstream optical system, the optical element having an axis of rotation and being subject to deposition of particles of flying debris from the plasma; and rotating the optical element about the axis of rotation whenever X-rays are being produced by the plasma. 23. The method of claim 22 , wherein the optical element is selected from a group consisting of X-ray reflective mirrors, X-ray diffractive elements, and filters. claim 22 24. The method of claim 22 , further comprising the step of monitoring a position of the optical element as the optical element is rotated about the axis of rotation. claim 22 25. The method of claim 24 , further comprising the step of correcting a position of the optical element whenever monitoring of the position of the optical element reveals a positional change that exceeds a preset specification. claim 24
	description	This application claims priority from U.S. Provisional Patent Application Ser. No. 61/463,461, filed on Feb. 17, 2011. The present invention relates generally to grazing incidence collectors (GICs), and in particular to cooling systems and methods for GICs used in extreme ultraviolet (EUV) lithography. EUV lithography is anticipated to be the lithographic process of choice for producing future generations of semiconductor devices having linewidths on the order of 32 nm and smaller. The wavelength of the EUV radiation is nominally 13.5 nm, which calls for the use of specialized optics to collect and image the EUV radiation. One type of EUV optical system used to collect the radiation from the light source is a grazing incidence collector (GIC). A GIC typically comprises one or more concentrically-arranged GIC mirror shells configured to receive radiation from the EUV source at grazing incidence and reflect the radiation to collect the radiation at an intermediate focus, such that the downstream radiation pattern in the far field is uniform to within a specification set by the overall system optical design. The radiation sources being considered for EUV lithography include a discharge-produced plasma (DPP) and laser-produced plasma (LPP). The conversion efficiency of these sources is only a few percent so that most of the energy used to generate the EUV radiation is converted to infrared, visible, UV radiation and energetic particles that can be incident upon the one or more GIC mirror shells. This radiation causes a substantial thermal load on the one or more GIC mirror shells. Consequently, each GIC mirror shell therefore needs to be thermally managed so that the heat absorbed by the GIC mirror does not substantially adversely affect GIC performance or damage the GIC. In particular, the thermal management needs to be carried out under high power loading conditions while preventing optical distortion of the one or more GIC mirror shells. This is because the uniformity and stability of the illumination of the reflective reticle is a key aspect of quality control in EUV lithography. In particular, the intensity and angular distributions of the EUV radiation delivered by the GIC to the input aperture of the illuminator must not change significantly as the thermal load on the GIC is cycled. This requires a high degree of stability of the radiation pattern formed in the far field, and this stability can be compromised by distortion or figure errors (and especially time-varying distortion and figure errors) in the GIC mirror shells. To date, essentially all GICs for EUV lithography have been used primarily in the laboratory or for developmental “alpha” systems under very controlled conditions of limited thermal loading. As such, there has been little effort directed to GIC thermal management architectures appropriate for GICs' use in commercially viable, high power EUV lithography systems. Since the increasing demand for higher EUV power also increases the thermal load on the GIC, more efficient and effective thermal management systems must be implemented for GICs for use in EUV lithography systems to minimize the optical distortion and other adverse effects on the GIC caused by large thermal loads. The GIC thermal managements systems, assemblies and methods disclosed herein provide important advantages over prior art GIC cooling systems. The use of an open-cell heat transfer (OCHT) material within a chamber immediately adjacent substantially the entire GIC mirror shell outer surface, combined with the substantially isotropic flow of a coolant through OCHT material, results in substantially uniform cooling of the GIC mirror shell over the entire GIC mirror shell. This is a result of the transfer of significant amounts of heat from the GIC mirror shell through the OCHT material to the coolant. This architecture avoids spatial modulations of the GIC mirror shell that can occur when using networks of cooling lines in thermal contact with the GIC mirror shell, and it enables GIC mirror thermal stability even at very high power loading onto the collector. Moreover, the GIC thermal management assemblies disclosed herein enable high coolant flow rates while adding only a few millimeters of width to the GIC mirror shell. This results in a low profile design that allows for a nested GIC mirror shell configuration without obscuring the optical pathways between the EUV radiation source and the intermediate focus. The OCHT material has a large effective surface area for cooling that provides a relative large convective cooling capacity. The inherent high heat transfer coefficient of the OCHT material, coupled with the relatively high coolant flow rate, provide an efficient mechanism for removing up to (and if necessary more than) 10 kW per shell of absorbed power, while limiting the temperature increase of the GIC mirror shell. An aspect of the thermal management system includes four main features. The first is a jacketed chamber configured to allow for “global” coolant flow over the back surface of the GIC mirror shell. The second is the OCHT material adjacent the back surface of the GIC mirror shell that serves to amplify the cooling effect as compared to flowing the coolant without the OCHT material. The third is a plenum system designed to supply sufficient coolant in an azimuthally symmetric way from input end to output end without obstructing working radiation from the EUV source. The fourth is a shield to protect the leading edge from heat and erosion. An aspect of the disclosure is a grazing incidence collector (GIC) thermal management assembly that employs the flow of a coolant. The GIC thermal management assembly includes a GIC mirror shell, a jacket and an open-cell, heat transfer (OCHT) material. The GIC mirror shell has a reflective inner surface, an opposite outer surface, and first and second mirror ends; The jacket has an inner surface and first and second jacket ends. The jacket and GIC mirror shell has first and second interfaces at the respective first and second mirror and jacket ends to define fluidly sealed chamber between the inner surface of the jacket and outer surface of the GIC mirror shell. The sealed chamber has input and output ends that define respective input and output plenums having respective input and output apertures. The open-cell, heat transfer (OCHT) material is contained with the sealed chamber. The OCHT material is thermally connected to the outer surface of the GIC mirror shell and the inner surface of the jacket. The OCHT material serves to support the flow of the coolant therethrough from the input plenum to the output plenum. In the GIC thermal management assembly, the OCHT material is preferably mechanically connected to the GIC mirror shell and the jacket. In the GIC thermal management assembly, the coolant is preferably one of a liquid and a gas. In the GIC thermal management assembly, at least one of the first and second interfaces preferably comprises a compliant feature. In the GIC thermal management assembly, the compliant feature is preferably configured to be compliant when subject to forces associated with assembling the GIC thermal management assembly but substantially non-compliant when subjected to hydrostatic forces associated with said flow of coolant through the chamber and the OCHT material. In the GIC thermal management assembly, the compliant feature is preferably formed from the same material as the jacket. In the GIC thermal management assembly, the compliant feature preferably comprises an epoxy. In the GIC thermal management assembly, the compliant feature preferably includes a plurality of grooves formed in the jacket at one or both jacket ends. In the GIC thermal management assembly, the jacket and the GIC mirror shell are preferably either welded together or epoxied together. In the GIC thermal management assembly, the OCHT material preferably comprises as least one of: a metal foam, one or more springs, and a metal mesh. In the GIC thermal management assembly, the OCHT material preferably comprises metal foam having a pore density of between 20 pores per inch (PPI) and 100 PPI. In the GIC thermal management assembly, the OCHT material preferably comprises metal foam, and the metal foam comprises at least one of Al, C, SiC, Cu and Ni. In the GIC thermal management assembly, the interfaced jacket and GIC mirror shell preferably has a width at respective leading and trailing edges of between 3 mm and 10 mm. In the GIC thermal management assembly, the OCHT material is preferably thermally contacted to the inner surface of the jacket with intermediate contact layers. In the GIC thermal management assembly, the intermediate contact layers preferably provide a mechanical bond between the OCHT material, the GIC mirror shell and the jacket. In the GIC thermal management assembly, the interfaced jacket and GIC mirror shell preferably defines a GIC cooling structure having a leading end and a trailing end. The leading end includes a shield. In the GIC thermal management assembly, the shield preferably comprises a cooled ring. In the GIC thermal management assembly, the shield preferably includes an inner surface adjacent the leading end and an opposite outer surface. The shield preferably further comprises either tungsten or a molybdenum layer. The GIC thermal management assembly preferably further comprises input and output coolant lines fluidly respectively attached to the input and output plenums. Another aspect of the disclosure is a thermally managed GIC mirror system. The thermally managed GIC mirror system includes the above-mentioned GIC thermal management assembly and a coolant supply unit. The coolant supply unit is fluidly connected to the input and output coolant lines. The coolant supply unit is configured to provide the fluid of the coolant under pressure to the input plenum via the input coolant line and receive the fluid of the coolant from the output plenum via the output coolant line. The thermally managed GIC mirror system preferably further includes the input and output plenums being configured to provide coolant to and receive coolant from the OCHT material in an azimuthally symmetric manner. The thermally managed GIC mirror system preferably further includes the system having a pressure drop along the azimuthal direction of the input and output plenums of less than 2 bar. In the thermally managed GIC mirror system, the coolant preferably has a flow rate between the input and output plenums of between 5 liters per minute and 60 liters per minute. The thermally managed GIC mirror system preferably further includes multiple GIC thermal management assemblies fluidly connected to the coolant supply unit. The GIC mirror shells are preferably configured in a nested configuration. Another aspect of the disclosure is an extreme ultraviolet (EUV) lithography system for illuminating a reflective reticle. The EUV lithography system includes a source of EUV radiation, the above-mentioned thermally managed GIC mirror system and an illuminator. The thermally managed GIC mirror system is configured to receive the EUV radiation and form collected EUV radiation. The illuminator is configured to receive the collected EUV radiation and form condensed EUV radiation for illuminating the reflective reticle. The EUV lithography system is preferably for forming a patterned image on a photosensitive semiconductor wafer. The EUV lithography system preferably further includes a projection optical system. The projection optical system is preferably arranged downstream of the reflective reticle and configured to receive reflected EUV radiation from the reflective reticle and form therefrom the patterned image on the photosensitive semiconductor wafer. It is to be understood that both the foregoing general description and the following detailed description present example embodiments intended to provide an overview or framework for understanding the nature and character of the disclosure as it is claimed. The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments of the invention and together with the description serve to explain the principles and operations of the disclosure. The drawings and the claims constitute part of this disclosure, and the claims shall be considered as being incorporated into and part of the detailed description set forth below. The various elements depicted in the drawing are merely representational and are not necessarily drawn to scale. Certain sections thereof may be exaggerated, while others may be minimized. The drawing is intended to illustrate an example embodiment of the invention that can be understood and appropriately carried out by those of ordinary skill in the art. FIG. 1 is schematic diagram of an example EUV source-collector module or SOCOMO 10 that has a central axis A1 and that includes a GIC mirror system 20 arranged along the central axis A1. GIC mirror system 20 has an input end 22 and an output end 24. GIC mirror system 20 also includes GIC mirror assembly 100 and a GIC shell cooling assembly 150 arranged in operative relation thereto, and which are discussed in greater detail below. SOCOMO 10 includes an EUV radiation source system 30 arranged along central axis A1 adjacent input end 22 of GIC mirror system 20 and that generates an EUV radiation source 34 at a source focus SF. EUV radiation source 34 emits EUV radiation 40 having a wavelength of nominally 13.5 nm. Example EUV radiation source can be a laser-produced plasma (LPP) radiation source or a discharge-produced plasma (DPP) radiation source. GIC mirror system 20 is configured to receive from EUV radiation source 34 a portion of EUV radiation 40 and collect the EUV radiation 40 at an intermediate focus IF adjacent output end 24 and along central axis A1, where an intermediate source image 34′ is formed. When SOCOMO 10 is incorporated into an EUV lithography system, intermediate focus IF is located at or near an aperture stop AS for an EUV illuminator (see FIG. 19). An example EUV lithography system that uses GIC mirror system 20 is discussed in greater detail below. FIG. 2 is schematic side-view diagram of an example GIC mirror assembly 100 that includes one or more GIC mirror shells (“GIC shells”) 110, each having an input edge 112 at input end 22 and an output edge 114 at output end 24. GIC mirror assembly 100 includes a GIC shell support member 120 (also called a “spider”) that supports the GIC shells 110 in a nested and spaced-apart configuration at their output edges 114. Example GIC mirror assemblies are disclosed in U.S. Patent Application Publication No. 2010/0284511, and in U.S. patent application Ser. No. 12/735,525 and Ser. No. 12/734,829, which are incorporated by reference herein. An example GIC shell support member 120 is disclosed in U.S. patent application Ser. No. 12/657,650, which is incorporated by reference herein. FIG. 3 is a cross-sectional view of a top-portion of an example GIC mirror assembly 100 having eight GIC shells 110, where the outer five GIC shells 110 include two different shell sections S1 and S2 having different curvatures and optionally different coatings. FIG. 4 is an isometric view of an example prior art GIC shell 110 that has an inner surface 116, an outer surface 118 and optional flanges 115L (see end-on inset) and 115T respectively formed at input and output edges 112 and 114. Cartesian coordinates are shown for reference. An example GIC shell 110 is formed by electroforming and is made of Nickel or Nickel alloy. An example range of thicknesses of GIC shell 110 is 1 mm to 4 mm, with 1 mm to 2 mm representing exemplary thicknesses. FIG. 5 is similar to FIG. 4 but illustrates an example GIC shell cooling assembly 150 that includes GIC shell 110 interfaced with a cooling structure 151 that includes jacket 160 that covers outer surface 118 of the GIC shell 110. FIG. 6 is a Y-Z cross-sectional view of a portion of GIC shell cooling assembly 150. Jacket 160 includes an outer wall 164 having an inner surface 166 and an outer surface 168, and optional end walls 165L and 165T. GIC shell cooling assembly 150 includes a leading end 170L (also referred to as the input end) and a trailing end 170T (also referred to as the output end), with the leading end 170L being closest to EUV radiation source 34 and trailing end 170T farthest from the EUV radiation source 34 when the GIC shell cooling assembly 150 is incorporated into SOCOMO 10. In an example, outer wall 164 of the jacket 160 includes input and output apertures 169L and 169T adjacent end walls 165L and 165T, respectively, for flowing a coolant 172 (see FIG. 7) as discussed below. Example materials for jacket 160 include any machinable metal, with Nickel and Nickel alloy being exemplary choices. An example thickness for outer wall 164 of the jacket 160 is in the range from 1 mm to 3 mm. jacket 160 and outer surface 118 of GIC shell 110 define a chamber 180 through which coolant 172 can flow. In an example, the width W from inner surface 116 of GIC shell 110 to outer surface 168 of the jacket 160 is in the range from 2 mm to 10 mm, with 3 mm to 7 mm being an exemplary range. In a commercial EUV lithography system, the SOCOMO 10 is expected to be subjected to 20 kW to 60 KW, which represents an enormous thermal load. The thermal management of each GIC shell 110 must be implemented within the constraints of the optical design of the particular GIC mirror system 20. In particular, in GIC mirror systems 20 having multiple GIC shells 110, the GIC shells 110 are arranged in a nested and concentric (or substantially concentric) configuration (see e.g., FIG. 2 and FIG. 3), and the GIC shell cooling assembly components must fit within gaps or “dark regions” between the GIC shells 110 so that the optical pathways from the EUV radiation source 34 to the intermediate focus IF remain substantially unobstructed. The relatively narrow width of GIC shell cooling assembly 150 is amenable for forming a nested GIC mirror system 20 without substantially obstructing the optical pathways. With reference now to FIG. 7, GIC shell cooling assembly 150 further includes a layer 200 of an open cell heat transfer (OCHT) material 202. An example OCHT material 202 an open-cell, porous, thermally conducting (i.e., non-thermally insulating) material that has a high heat transfer. Layer 200 is configured so that OCHT material 202 substantially fills chamber 180. In an example, OCHT material 202 is rigid and has mechanically high tensile strength. An example OCHT material 202 is metal foam formed from any of a number of commercially available materials including Al, C, SiC, Cu and Ni, or constituted by solid metal or by a non-metal core structure (e.g., carbon) with a metal coating. In an example, the density of the metal foam can typically be in the range of 3-15% of solid density and an example pore size is in the range of 0.2-3 mm. An example metal foam has a pore density in the range of 20 to 100 pores per inch (PPI). Another example OCHT material 202 comprises one or more springs or spring-like metal materials configured (e.g., as wrapped or a nested wrap of one or more lengths of springs) so that a coolant 172 can flow through the OCHT material 202 and remove heat. Another example OCHT material 202 comprises a mesh, such as a copper or other type of metallic or metallic-coated mesh. In an example, OCHT material 202 performs the following functions: 1) provides mechanical rigidity to prevent chamber 180 from expanding under high hydrostatic pressure when the OCHT material 202 is connected to (e.g., bonded to) GIC shell 110 and jacket 160; 2) generates micro-turbulence in the coolant flow to reduce or eliminate the formation of substantial boundary layers at outer surface 118 of the GIC shell 110 or inner surface 166 of the jacket 160; 3) transfer heat from GIC shell 110 via thermal conduction so that the flow of coolant 172 through the OCHT material 202 can remove heat from chamber 180; and 4) presents a relatively large effective surface area to efficiently transfer heat from the OCHT material 202 to the coolant 172 via thermal convection. In another example, the OCHT material 202 performs one or more of the above-described functions. With reference to FIG. 7, layer 200 includes an inner surface 210 (which is really an “effective inner surface,” given the porous nature of OCTM material 202) adjacent to outer surface 118 of the GIC shell 110 and an (effective) outer surface 212 adjacent to inner surface 166 of the jacket 160. In an example, inner surface 210 is conformal relative to outer surface 118 of the GIC shell 110 and outer surface 212 is conformal with inner surface 166 of the jacket 160. The two close-up insets INSET A and INSET B illustrate the aforementioned examples of metal-foam-based and spring-based OCHT materials 202. In an example, end portions of chamber 180 adjacent leading and trailing ends 170L and 170T of the GIC shell cooling assembly 150 respectively serve as ring-shaped input and output plenums 230L and 230T through which coolant 172 can circumferentially flow. Other forms of plenums can be used, as described below in connection with FIG. 16B. In an example, at least one of input and output plenums 230L and 230T does not contain any OCHT material 202. In an example, layer 200 includes input and output ends 201L and 201T that serves to respectively define input and output plenums 230L and 230T that are void of OCHT material 202 so that coolant 172 can more freely flow therein and therethrough. It is generally preferred that there be a relatively low pressure drop in the input and output plenums 230L and 230T when feeding and removing coolant 172 thereto and therefrom so that coolant 172 has substantially uniform azimuthal flow. Layer 200 is generally configured to control the heat transfer and coolant flow dynamics to optimize convective cooling of GIC shell 110 when the GIC shell 110 is used to collect EUV radiation 40. Layer 200 also preferably contributes to making jacket 160 mechanically stable under the hydrostatic pressure caused by the flow of coolant 172. An example range of expected hydrostatic pressure is 4 bars to 8 bars. Thus, an example OCHT material 202 has an elastic modulus of about 100 MPa or greater. Also in an example, the yield strength of the bonds that connect OCHT material 202 GIC shell 110 and jacket 160 is greater than about 10 bar=1 MPa. In an example, the transfer of heat from GIC shell 110 into chamber 180 is maximized by increasing the effective surface area and thermal conductivity of layer 200. This corresponds to increasing the density and decreasing the pore size (or interstitial size) of OCHT material 202. However, high flow rates of coolant 172 are also required for effective cooling and, for a given pressure differential, the flow rate increases with lower density and larger pore (interstitial) size. The optimum cooling is thus obtained by balancing these competing factors. Layer 200 acts as a convective cooling agent that significantly increases the effective thermally conducting surface area of the interface between coolant 172 and GIC shell 110. As a rule of thumb, each millimeter of thickness of metal foam layer 200 may add an amount of surface area that is substantially equivalent to the original surface area of inner surface 116 of the GIC shell 110. This will typically depend on the quality of the thermal contact between the metal foam and the GIS shell 110. Thus, to enhance the heat transfer, layer 200 is preferably in good thermal contact with GIC shell 110. Thus, in an example embodiment, layer 200 is thermally and mechanically contacted to outer surface 118 of the GIC shell 110 as well as to inner surface 166 of the jacket 160. FIG. 8 is a Y-Z cross-sectional view of an example GIC shell cooling assembly 150 wherein GIC shell 110 includes two different shell sections S1 and S2 having different curvatures and optionally different reflectivity coatings. GIC shell 110 also includes two flanges 115L and 115T at its input and output edges 112 and 114. Likewise, jacket 160 includes flanges 167L and 167T at its input and output ends 165L and 165T. Another option for this configuration is to make flanges 115L and 115T of the GIC shell 110 larger and for jacket 160 to have no flanges. This latter option would serve to move the locations where GIC shell 110 and jacket 160 are secured (e.g., welded or brazed or even epoxied) to one another away from inner surface 116 of the GIC shell 110, i.e., the optical surface where the thermal loading from the source heating is greatest. With reference now to FIG. 9, in an example, respective intermediate contact layers 220 provide both thermal and mechanical contact between layer 200, inner wall 166 of the jacket 160 and outer surface 116 of the GIC shell 110. For example, once layer 200 is mechanically attached to outer surface 118 of the GIC shell 110 (e.g., before the GIC shell 110 is removed from its mandrel), it is submerged in a plating solution to deposit a thin layer (e.g., between 10 microns and 100 microns) of metal over surfaces 210 and 212 of layer 200, including the places where the layer 200 contacts GIC shell 110 and jacket 160. This process forms intermediate contact layer 220 that bonds inner surface 210 of the metal foam layer 200 to outer surface 118 of the GIC shell 110 and outer surface 212 of the layer 200 to inner surface 166 of the jacket 160. In this approach, intermediate contact layers 220 comprise a plating metal, which can be any high-conductivity metal. One particularly attractive choice for the plating metal is Ni, in order to minimize the variation between the foam and the GIC shell 110 (also Ni) of the coefficient of thermal expansion. In an example, the above-described electroforming process can coat inner surface of OCHT material 202. A variety of materials and processes can be used for intermediate contact layers 220 besides those described herein by way of illustration. Another method for contacting layer 200 to at least one of outer surface 118 of the GIC shell 110 and inner surface 166 of the jacket 160 employs an electroless process. One such electroless process involves circulating the plating solution through chamber 180 after the GIC shell cooling assembly 150 is assembled. This approach has the advantage of contacting layer 200 to outer surface 118 of the GIC shell 110 and to inner surface 166 of the jacket 160. This configuration allows for sufficient cooling while also increasing the mechanical stiffness of GIC shell cooling assembly 150 by mechanically connecting GIC shell 110 and jacket 160 via layer 200. This further serves to reduce the possibility of mechanical distortion of GIC shell cooling assembly 150 and in particular reflective inner surface 116 of the GIC shell 110 when the pressurized coolant 172 is introduced to the GIC shell cooling assembly 150. Another method for contacting layer 200 to at least one of outer surface 118 of the GIC shell 110 and inner surface 166 of the jacket 160 employs a thermally conducting pliable material (e.g., a paste), such as silver epoxy. An example silver epoxy thickness of intermediate contact layers 220 is between 100 and 200 microns thick. In an example, one can employ bonding techniques for the two surfaces 210 and 212 of layer 200. For example, an electroless Ni bonding approach that uses 25 micron to 100 microns of material may be used to bond layer 210 to one of the GIC shell 110 and the jacket 160, while a conducting epoxy that is hundreds of microns thick can be used to bond the remaining surface. A powder coating (e.g., with a thickness of between about 50 to 200 microns might be used. Powder coatings flow over and coat surfaces and so may prove useful when bonding an open-cell material such as OCHT material 202. An example embodiment includes using an electroforming method to bond the OCHT material 202 to the GIC shell 110 while the GIC shell 110 is still in contact with the mandrel, and then using an epoxy or a powder coating method or an electroless Nickel method to attach the OCHT material 202 to the jacket 160. In an example embodiment, layer 200 is formed within chamber 180, as opposed to introducing externally fabricated layer 200. For example, a non-conducting matrix material such as vitreous carbon foam can be arranged in chamber 180, the chamber then sealed with jacket 160, and then the structure electroformed with Nickel to create a Ni-based metal foam OCHT material 202 within the chamber 180. In another example, chamber 180 can be filled with chips or filings of a conductive material and then the material electroformed to form the OCHT material 202. Also in an example, an electroforming process is used to form a nickel-based metal foam OCHT material 202. An in situ method of layer 200 can be used to ensure that the layer 200 is substantially conformal with outer surface 118 of the GIC shell 110 and inner surface 166 of the jacket 160. GIC Mirror System FIG. 10 is a schematic diagram of an example GIC mirror system 20 comprising GIC shell cooling assembly 150 integrated with GIC shell 110 (see FIG. 5). The example GIC mirror system 20 (see FIG. 1) of FIG. 10 shows only a single GIC shell 110. GIC shell cooling assembly 150 further includes a coolant supply unit 250 fluidly connected to the GIC shell cooling assembly 150 via an input cooling line 240L fluidly connected to input plenum 230L at input aperture 169L and an output cooling line 240T fluidly connected to output plenum 230T at output aperture 169T. Input and output cooling lines 240L and 240T are fluidly connected to coolant supply unit 250. It is noted here that the input and output plenums 230L and 230T can be switched so that coolant 172 is introduced at the opposite end of the GIC shell cooling assembly 150, and the example shown in FIG. 10 is one example configuration. FIG. 11 is a cut-away view of a section of GIC shell cooling assembly 150 along with input and output cooling lines 240L and 240T. In another example, a GIC mirror assembly 100 having multiple GIC shells 110 and thus multiple GIC shell cooling assemblies 150 is used, with the GIC shell cooling assemblies 150 connected to a common coolant supply unit 250 or to separate cooling supply units. In the general operation of GIC mirror system 20, EUV radiation 40, as well as other radiation from EUV radiation source 34, is incident upon reflective inner surface 116 of GIC shell 110, which receives and collects at least this narrowband EUV radiation 40 at intermediate focus IF (see FIG. 1). This process whereby EUV radiation 40 from the EUV radiation source 34 is incident on the GIC shell 110 serves to heat GIC shell 110. Thus, GIC mirror system 20 causes coolant supply unit 250 to provide coolant 172 to input plenum 230L. Coolant 172 flows under pressure around the ring-shaped input plenum 230L and also into annular-shaped chamber 180, including into layer 200 enclosed therein. Coolant 172 flows under pressure through layer 200 from the input plenum 230L to output plenum 230T. During its travel through layer 200, coolant 172 extracts heat from OCHT material 202 as the heat from the EUV radiation process is conducted from GIC shell 110 into layer 200. The pressure drop ΔP between input and output plenums 230L and 230T is selected so that it does not substantially deform GIC mirror assembly 100. In an example embodiment, the input and output plenums 230L and 230T and their corresponding input and output cooling lines 240L and 240T are configured so that most of the pressure in chamber 180 is due to the pressure buildup in the input and output cooling lines 240L and 240T. In an example, the pressure drop ΔP within chamber 180 (i.e., between the input and output plenums 230L and 230T) is less than 3 bars with a maximum pressure PMAX of 6 bars. A most desirable pressure drop would be about 1 bar or less. The amount of heat that needs to be removed, the heat capacity of the coolant 172 and the pressure drop ΔP defines the coolant flow rate. An example flow rate of coolant 172 is in the range of 10 to 60 liters/minute. Under different heat load conditions we can vary the flow rate to set the temperature difference across the GIC shell 110. It is estimated that the average temperature difference ΔT between leading and trailing ends 170L and 170T can be kept to as low as 1° C. In an example, ΔT is about a few degrees centigrade. Jacket Connection to GIC Shell In an example embodiment, jacket 160 is formed as a separate part from GIC shell 110 and so needs to be interfaced with GIC shell 110. The resulting chamber 180 needs to be sealed able to hold the internal pressure without mechanical failure or leakage and be vacuum-compatible, and conform to restrictive EUV lithography non-contamination requirements. One method for interfacing jacket 160 and GIC shell 110 is via welding, e.g., to form a welded joint. With reference again to FIG. 8, in one example, flanges 115L and 115T of the GIC shell 110 and the corresponding flanges 167L and 167T of the jacket 160 are precision micro-welded together using either a laser or electron beam to form respective welded joints 302L and 302T that define respective interfaces 304L and 304T between GIC shell 110 and jacket 160. In one example, the flanges are welded at their edges while in another example the flanges are overlapped and welded so that interfaces 304L and 304T have a greater surface area than an edge-to-edge interface. This approach keeps the localized heating associated with the welding process from affecting the active surface of the reflecting GIC shell 110. As noted above, GIC shell 110 may have larger flanges and jacket 160 may have no flanges, and the chamber 180 sealed at the flange edge of the GIC shell 110 and the edge of the jacket 160. A consideration in forming GIC shell cooling assembly 150 is that stress can be introduced at one or more of interfaces 304L and 304T and deform GIC shell 110 during assembly of the GIC shell cooling assembly 150, thereby compromising the optical figure of reflective inner surface 116. Thus, with reference to the close-up view of GIC shell cooling assemblies 150 of FIG. 12 through FIG. 15B, in an example embodiment, GIC shell cooling assembly 150 includes at least one compliant interface 304L and 304T. The compliant interface 304L and 304T is designed to be compliant when subjected to mechanical forces associated with assembling GIC shell cooling assembly 150, but not substantially compliant when subjected to hydrostatic pressures associated with the flow of coolant 172 through chamber 180 and OCHT material 202 contained therein. In one example, compliant interface 304L and 304T includes a compliant feature 310. In FIG. 12, compliant feature 310L is shown disposed between overlapping flange 115L of the GIC shell 110 and flange 167L of the jacket 160. In an example, compliant feature 310 comprises a hinge, a flexure, a bellows, a gasket, or grooved section of flange 115L of the GIC shell 110 or flange 167L of the jacket 160. In another example, compliant feature 310 includes an epoxy with low outgassing properties. Compliant feature 310 is operable to absorb residual strain caused by interfacing GIC shell 110 and jacket 160 to prevent the residual strain from propagating to reflective inner surface 116 of the GIC shell 110 while also being substantially non-compliant when subjected to the hydrostatic forces associated with coolant flow during the operation of GIC shell cooling assembly 150. In another example, compliant interface 304L and 304T includes a welded or brazed joint. FIG. 14 is a cross-sectional view of an example GIC shell cooling assembly 150 that illustrates an example compliant feature 310. In the example of FIG. 14, trailing-edge flange 115T of the GIC shell 110 extends all the way to the edge of jacket 160, which has no flange. However, outer wall 164 of the jacket 160 includes an end region 164R configured as ring-type compliant feature 310 by the inclusion of grooves 312 formed on jacket wall inner and outer surfaces 166 and 168. Grooves 312 may be machined into outer wall 164 of the jacket 160 on one or both sides, with the latter embodiment shown in FIG. 14. Alternatively, the end region 164R of the jacket 160 may be a separate jacket piece that is formed separately from jacket 160 and then is attached (e.g., welded) thereto to create the ring-type complaint feature 310. In an example, compliant feature 310 is formed by chemical milling or machining to remove material and provide a flexural capability to the otherwise rigid ring-like structure. The compliance of the compliant feature 310 can be varied by adjusting the amount of material removed. Thus, in an example, the spacing and depth of grooves 312 are selected to provide the right balance of complaint feature 310 being compliant when subjected to mechanical stresses and strains associated with assembling GIC shell cooling assembly 150, while also being substantially non-compliant when subjected to hydrostatic forces associated with the flow of coolant 172. One method to insure the non-compliance when subjected to hydrostatic forces associated with the flow of coolant 172 is to bond the OCHT material 202 to the compliant structure after the welding process is completed. In this way, there is compliance when the high temperature welding process occurs, but then the bonding is employed which provides rigid structure and support to the otherwise compliant feature 310 before the hydrostatic pressure from the flow of coolant 172 is introduced. In an example jacket 160 is spot-welded at various locations at the interface between trailing-edge flange 115T and the corresponding jacket edge. An example spot-weld 320 formed using a laser beam LB is shown by way of illustration. The laser welding process is carried out, for example, by placing the partially assembled GIC shell cooling assembly 150 on a turntable and then spot welding at various locations at the flange-edge interface. The process can then be repeated as the turntable spins to form the final laser weld that yields a good seal between jacket 160 and GIC shell 110. As discussed above, sealed GIC shell cooling assembly 150 supports closed-loop circulation of coolant 172 through chamber 180 and OCHT material 202 therein to convectively remove heat from GIC shell 110. Coolant 172 can be either gas or liquid. For smaller absorbed thermal loads of up to about 1 kW per GIC shell 110, a gas coolant 172 such as He can be used. For larger thermal loads ranging up to the maximum anticipated load of about 10 kW per GIC shell 110, coolant 172 is preferably a liquid such as water. In either case, coolant supply unit 250 preferably includes a filtration unit 252 operable to remove small particulates (>5 microns) that can deposit in and clog the pores of a metal foam. The conformal geometry of HHT metal foam layer 200 within chamber 180 allows coolant 172 to flow uniformly through the metal foam layer 200. In certain instances, it may be preferable to flow coolant 172 from leading end 170L to trailing end 170T of GIC shell cooling assembly 150. Thus, in the examples discussed herein, the leading-end plenum 230L is referred to as the input plenum. However, as mentioned above, GIC shell cooling assembly 150 can be configured so that coolant 172 flows from trailing-end plenum 230T to leading-end plenum 230L. The input plenum 230L may also be located at a location other than at an edge of the GIC shell cooling assembly 150, such as described in greater detail below. In one example that seeks to achieve substantially azimuthally symmetric coolant flow, the pressure drop ΔP across the azimuthal length of input plenum 230L is made small, e.g., smaller than 1 bar and preferably substantially smaller than 1 bar. In one example that seeks to achieve optimum temperature control of GIC shell 110, the temperature of coolant 172 is maintained at or close to the ambient temperature. For the anticipated thermal loads associated with a commercially viable SOCOMO 10, such cooling requires relatively high coolant flow rates. For example, when coolant 172 is water and the flow rate is 60 liters/minute, the energy balance in high power loading conditions requires that there be an increase in the water temperature of 1° C. for every 4 kW of power removed. Such high flow rates imply high operating pressures with corresponding high flow velocities. In particular, the momentum of coolant 172 entering input plenum 230L from input cooling line 240L must be dissipated without applying significant force to GIC shell 110. To this end, in an example, the flow of coolant 172 from coolant supply unit 250 can be introduced tangentially to GIC shell 110 via input plenum 230L, or in a zig-zag configuration discussed in greater detail in connection with the example shown in FIG. 16. An example input plenum 230L is either void of OCHT material 202 or contains a more porous (e.g., lower density, larger pore size) OCHT material 202. Coolant 172 then circulates about the circumference of input plenum 230L while also uniformly feeding coolant 172 into layer 200. This coolant 172 then flows from input plenum 230L to output plenum 230T through OCHT material 202 preferably without having a substantial circumferential flow component once the coolant flow is initiated and reaches an equilibrium flow state. The avoidance of a circumferential flow facilitates azimuthally symmetric cooling. The cross-sectional area of chamber 180 can be relatively large due to the large diameter of some GIC shells 110. For example, if chamber 180 contains a 3 mm thick metal foam layer 200 on a 200 mm diameter GIC shell 110, the cross-sectional area of chamber 180 is 19 cm2. The pressure drop ΔP from input plenum 230L to output plenum 230T is expected to be small for such a large cross-section, even at a relatively high required coolant flow rates of up to about 60 liters/minute. However, the flow of coolant 172 can create an unacceptable deformation inner (reflecting) surface 116 of the GIC shell 110 due to hydrostatic pressure applied to outer surface 118 of the GIC shell 110. In instances where such deformation could present an issue, the contact between layer 200 with jacket 160 and GIC shell 110 is made in a manner that provides a strong bond so that the layer contributes significantly to the structural integrity of GIC shell cooling assembly 150. An example method for reducing the hydrostatic pressure is to employ a ‘push-pull’ pumping configuration for the coolant circulation. In this approach coolant supply unit 250 includes a suction pump 254 added to output cooling line 240T and operated to reduce the average pressure inside the chamber 180. FIG. 16A is a schematic cross-sectional view of an example GIC shell cooling assembly 150 where the cross-sectional area of input plenum 230L is increased by extending the input plenum 230L. Here, input plenum 230L is folded over on itself so that the flow path of coolant 172 within the input plenum 230L has a zig-zag section. Input plenum 230L may include OCHT material 202, which may have a porosity different than (e.g., less than) the OCHT material 202 that resides adjacent outer surface 118 of the GIC shell 110, or it may be void of any OCHT material 202. The extended input plenum 230L is arranged so that it resides in the aforementioned “dark space” when GIC shell cooling assembly 150 is incorporated into a GIC mirror assembly 100 that includes nested GIC shells 110. FIG. 16B is a cross-sectional view of an example GIC mirror assembly 100 shown in relation to a EUV radiation source 34, illustrating an example of a plenum architecture for GIC shell cooling assembly 150. Input and output plenums 230L and 230T are built into jacket 160 and within the shadow area or “dark region” DR between GIC shells 110. Input cooling line 240L leads from the output edge 114 of the GIC shell 110 to the input edge 112 through dark region DR. Coolant 172 is fed into input plenum 230L at an angle to create a circumferential vortex and have a good fill of the input plenum 230L. Coolant 172 is thus distributed along the entire circumference of input plenum 230L in a larger plenum region and then into a smaller region small plenum. Coolant 172 then flows primarily axially through the OCHT material 202 within chamber 180 and to output plenum 230T. Coolant 172 is then removed from output plenum 230T via output cooling line 240T. FIG. 16C is a side-view of an example GIC shell 110 with an example OCHT material 202 in the form of one or more lengths of springs 203 wound around the outer surface 118 of the GIC shell 110. In an example, the spring configuration will be optimized to maximize the effective heat transfer to the coolant 172. In doing so, a guiding rule of thumb for spring configuration design is to have a ratio of d/D>0.2, where d=diameter of the spring wire material and D=the loop diameter of the spring 203. In an example, the spring loop separation along the spring length should be approximately 2d and the center-to-center separation (along the axis of the GIC shell 110) of adjacent springs 203 should be approximately D. In FIG. 16C, only the upper portion of the GIC shell 110 is shown covered with spring(s) 203 for ease of illustration. FIG. 16D is a cross-sectional view of another example of GIC shell cooling assembly 150 showing the input and output plenums 230L and 230T with flow transition regions TR defined by baffles BF, and a main circulation region CR farther removed from the respective input and output edges 112 and 114. Coolant 172 is introduced to the circulation region CR of the input plenum 230L at the input edge 112. The transition region TR converts the azimuthal flow in the circulation region CR to axial flow that feeds the cooling jacket uniformly. The coolant flows through the OCHT material 202 and is ejected into the transition region TR of the output plenum 230T at the output edge 114. The flow then transforms from axial to azimuthal flow in the circulation region CR of the output plenum 230T. For optimal thermal management performance, the pressure drop for one trip around the circulation region CR should be much less than the pressure drop across the transition region TR. In particular, a coolant-fluid molecule (e.g., water molecule) injected into the input plenum 230L should preferably circulate several times before it migrates into the cooling jacket 160. Similarly, a coolant-fluid molecule exiting the jacket 160 should circulate several times in the output plenum 230T before entering the output cooling line 240T. The size of the input and output plenums 230L and 230T is generally determined by the cross-sectional area required to minimize the pressure in the circulation region CR. The pressure gradient in a square channel at flow rate w is given by, ⅆ p ⅆ x = ρ ⁢ ⁢ f ⁢ ⁢ w 2 2 ⁢ A 5 / 2 ( 1 ) Here ρ is the water mass density (1000 kg/m3) and f is the friction coefficient. A reasonable value for the friction coefficient in the case of turbulent flow and smooth walls is 0.02. For a flow rate of 15 l/min (5×10−4 m3/s), to obtain a manageable pressure gradient of 0.05 bar/m requires a cross-sectional area of 1.9 cm2. This is why the plenum 230L and 230T should be located on the outside of the cooling jacket 160 where more space is available. Modeling of the cooling jacket 160 showed that the flow in the circulation region CR tends to expand axially and spill into the jacket 160 well before completing a revolution in the plenum 230L and 230T. This indicates that the plenum 230L and 230T also needs a transition region TR of relatively high pressure that converts the azimuthal flow to a uniform axial flow into the jacket 160. The pressure in the transition region TR can be controlled using baffles BF to decrease the effective channel size as shown in FIG. 16D. In the case of the output plenum 230T, the baffles BF can be tilted to help form the azimuthal flow in the circulation region CR. The input and output cooling lines 240L and 240T should be oriented in the azimuthal direction to facilitate the circulation. In an example, coolant 172 is filtered and conditioned to prevent algae growth and/or clogging. GIC Cooling Assembly with Heat Shield FIG. 17A is a conceptual schematic plot of the thermal load (arbitrary units) as a function of axial length along inner (reflecting) surface 116 of GIC shell 110 for a GIC shell cooling assembly 150 arranged in a SOCOMO 10 and subjected to EUV radiation 40, as well as other thermal loading. It is expected that most of the thermal load occurs at leading end 170L, e.g., models indicate that about 20% of the thermal load is absorbed over the first 10 mm closest to the leading end 170L. Thus, for a 5 kW thermal load, the GIC shell 110 at leading end 170L can experience about a 1 kW thermal load. The thermal load illustrated in FIG. 17A is capable of being thermal managed by the thermal management systems disclosed herein. FIG. 17B is similar to FIG. 17A, except that it shows the actual expected thermal load on the entire GIC shell cooling assembly 150, including the very leading end 170L, for example the flange 115L of the GIC shell 110 which serves a mechanical not an optical function. So there is a very large amount of heat (“leading edge heat”) LEH that will need to be dissipated at the leading end 170L. Rather than trying to manage this intense leading end thermal load using only the thermal management systems described above, in an example embodiment, an additional heat shield is used to reduce the amount of this leading-end heating which is incident on the non-optical leading surface. FIG. 18A is a close-up cross-sectional view of leading end 170L of an example GIC shell cooling assembly 150 that includes an annular shield 350 arranged adjacent to and in contact with the leading end 170L. Shield 350 includes an insulating member 356 with an inner surface 357 adjacent leading end 170L, and an opposite outer surface 358. Insulating member 356 is, in a preferred embodiment, made of a very low thermal conductivity material such as a ceramic (e.g., ceramic foam). An example shield 350 is configured to provide both thermal shield and shielding from erosion due to EUV radiation 40 and other radiation emitted by EUV radiation source 34. In an example, shield 350 includes a metal layer 360 on outer surface 358 of the insulating member 356. Metal layer 360 comprises a metal having a high melting temperature, and an exemplary metal for metal layer 360 is tungsten or molybdenum. Thus, the thermal load at leading end 170L is dissipated primarily by radiative loss from the metal layer 360 with very little transfer as conduction of heat to input plenum 230L via insulating member 356. Shield 350 may also serve the additional function of mitigating erosion of reflective inner surface 116 of the GIC shell 160, which in an example includes a gold separation layer covered with a ruthenium layer. For very high amounts of thermal load on the leading end 170L, the above-described passive shield 350 approach may need to be enhanced. Thus, FIG. 18B is similar to FIG. 18A and illustrates an example active thermal heat shield 350 in the form of a cooled ring 380 that runs around the leading end 170L of the GIC shell cooling assembly 110. Cooled ring 380 may be stood off from the leading end 170L to provide further heat shielding. The stand-off may be accomplished using stand-off elements such as a few attachment clips 382 attached to GIC shell cooling assembly 150. Alternatively, another stand-off structure (not shown) may be used that makes cooling ring 380 free-standing relative to the GIC shell cooling assembly 150. An exemplary material for cooling ring 380 is Nickel, and a suitable coolant 172 is water. In an example, the outer diameter of the cooling ring 380 is chosen to exactly shadow the leading end 170L of GIC shell cooling assembly 150. A constraint on the shield 350 of the cooling ring 380 is that its temperature must be maintained below 100° C. to keep water coolant 172 from boiling. However, in this case the low operating temperature of the heat shield ameliorates the thermal load at the attachment points. In an example, coolant 172 associated with GIC shell cooling assembly 150 can be shunted from input plenum 230L and returned to output plenum 230T. In another example, coolant 172 is provided to the cooled ring 380 via a coolant line (not shown) that resides in the obscuration provided by a GIC shell support member 120 (e.g., a spider). The flow rate of water as the coolant 172 required to cool the heat shield 350 of the cooling ring 380 is determined by the thermal load. To limit the temperature rise of the water to ΔT degrees for a thermal load of P watts, the coolant flow rate must be, f ⁡ ( in ⁢ ⁢ l ⁢ / ⁢ min ) = 6 × 10 4 ⁢ P ρ ⁢ ⁢ c ⁢ ⁢ Δ ⁢ ⁢ T ( 2 ) where ρ=1000 kg/m3 and c=4187 J/kg−K are the mass density and specific heat of the water. Assuming a maximum heat load of 2 kW and a maximum temperature rise (ΔT) of 30 degrees Kelvin a modest flow rate of ˜1 l/min will suffice. For a Nickel cooling ring inner diameter d=4 mm, the flow velocity is given by, v ⁡ ( in ⁢ ⁢ m ⁢ / ⁢ s ) = 2.1 × 10 - 5 ⁢ f ⁡ ( in ⁢ ⁢ l ⁢ / ⁢ min ) d ⁡ ( in ⁢ ⁢ m ) 2 ( 3 ) then for a flow rate of 1 l/min, the coolant fluid flow velocity is 1.3 m/s. The Reynolds number for the flow is given by, Re = vd v K ( 4 ) where μK=1×10−6(m2/s) is the kinematic viscosity of the water. In this case the Reynolds number is Re=5250, which is comfortably above the threshold of 2320 for the turbulent regime. It is preferred to have turbulent flow to increase the convective heat transfer between the tube walls and the flowing water. In the turbulent flow regime, the pressure drop in the tube is given by: ⅆ p ⅆ x ⁢ ( in ⁢ ⁢ bar ⁢ / ⁢ m ) = 1 × 10 - 5 ⁢ λ ⁢ ρ ⁢ ⁢ v 2 2 ⁢ d ( 5 ) where λ is the friction coefficient between the water and the channel walls. A reasonable value for the friction coefficient in the case of turbulent flow and smooth walls is 0.02. For an example GIC shell 110, the length of the Ni cooling ring 380 is about 1.3 m. The pressure drop through the heat shield 350 according to Eq. (5) is only ·p=0.055 bar. Thus, the heat shield 350 of the cooling ring 380 is desirable because it requires a modest flow rate of ˜1 l/min and a small pressure drop, which means that it is possible to divert a small amount of the water from the GIC shell cooling assembly 150 to the heat shield 350. The heat shield 350 blocks all radiation and particle flux incident on the input edge 112 of the GIC shell 110. Further, because it operates near ambient temperature, there is minimal heat transfer to the GIC shell 110 if attachment hardware is used to support the cooling ring 380 using the GIC shell cooling assembly 150. EUV Lithography System with GIC SOCOMO FIG. 19 is an example EUV lithography system (“system”) 400 according to the present invention. Example EUV lithography systems are disclosed, for example, in U.S. Patent Applications No. US2004/0265712A1, US2005/0016679A1 and US2005/0155624A1, which applications are incorporated herein by reference. System 400 includes a system axis ASy and EUV radiation source 34, such as a hot plasma source, that emits working EUV radiation 40 at ˜λ=13.5 nm. EUV radiation 40 is generated, for example, by an electrical discharge source (e.g., a discharged produced plasma, or DPP source), or by a laser beam (laser-produced plasma, or LPP source) on a target of Lithium, or Tin. EUV radiation 40 emitted from such a LPP source may be roughly isotropic and, in current DPP sources, may be limited by the discharge electrodes to a source emission angle of about θ=70° or more from system axis (optical axis) ASy. It is noted that the isotropy of the LPP source will depend on the type of LPP target, e.g., Sn droplets, Sn disc, Sn vapor, etc. System 400 includes a thermally managed EUV GIC mirror system 20 such as described above. Cooled EUV GIC mirror system 20 is arranged adjacent and downstream of EUV radiation source 34, with collector axis AC lying along system axis ASy. The GIC mirror assembly 100 of EUV GIC mirror system 20 collects EUV radiation 40 from EUV radiation source system 30, and the collected EUV radiation 40 is directed to intermediate focus IF where it forms an intermediate source image IS. An illumination system 416 with an input end 417 and an output end 418 is arranged along system axis ASy and adjacent and downstream of EUV GIC mirror system 20, with the input end 417 adjacent the EUV GIC mirror system 20. Illumination system 416 receives at input end 417 EUV radiation 40 from intermediate source image IS and outputs at output end 418 a substantially uniform EUV radiation beam 420 (i.e., condensed EUV radiation). Where system 400 is a scanning type system, EUV radiation beam 420 is typically formed as a substantially uniform line or arc i.e. ring field of EUV radiation 40 at reflective reticle 436 that scans over the reticle 436. A projection optical system 426 is arranged along (folded) system axis ASy downstream of illumination system 416. Projection optical system 426 has an input end 427 facing output end 418 of the illumination system 416, and an opposite output end 428. A reflective reticle 436 is arranged adjacent the input end 427 of the projection optical system 426 and a semiconductor wafer 440 is arranged adjacent the output end 428 of the projection optical system 426. Reticle 436 includes a pattern (not shown) to be transferred to semiconductor wafer 440, which includes a photosensitive coating (e.g., photoresist layer) 442. In operation, the uniformized EUV radiation beam 420 irradiates reticle 436 and reflects therefrom, and the pattern thereon is imaged onto photosensitive coating 442 of semiconductor wafer 440 by projection optical system 426. When the system 440 is a scanning system, the reticle image scans over the surface of photosensitive coating 442 to form the pattern over the exposure field. Scanning is typically achieved by moving reticle 436 and semiconductor wafer 440 in synchrony. Once the reticle pattern is imaged and recorded on semiconductor wafer 440, the patterned semiconductor wafer 440 is then processed using standard photolithographic and semiconductor processing techniques to form integrated circuit (IC) chips. Note that, in general, the components of system 400 are shown lying along a common folded system axis ASy in FIG. 19 for the sake of illustration. One skilled in the art will understand, for example, that there is often an offset between entrance and exit axes for the various components such as for illumination system 416 and for projection optical system 426. In addition, some systems 400 may include one or more folds to accommodate a desired system architecture, e.g., the orientation of the illuminator relative to GIC mirror system 20. It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention. Thus it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
	claims	1. A system, for treating a target tissue with x-ray radiation, comprising:a radiation source that emits x-rays, the x-rays having an energy between about 1 KeV and about 300 KeV;a collimator that collimates the emitted x-rays into an x-ray beam, the collimator having an inner cross-sectional dimension, the x-ray beam having a dose distribution at a beam spot in a plane at the target tissue, such that a dose of the x-ray beam at a region within the plane is less than about 20% of the dose at a centroid of the beam spot;wherein the region is located at a distance, away from the centroid of the beam spot, equal to about 70% of the inner cross-sectional dimension;an alignment system that aligns the x-ray beam with an axis traversing the target tissue and that positions the radiation source within about 50 cm from the target tissue; anda processing module that receives an input comprising a parameter of the target tissue and that, based on the parameter, outputs to the alignment system a direction for the x-ray beam to be emitted toward the target tissue. 2. The system of claim 1, wherein the alignment system is configured to align the x-ray beam repeatedly during a treatment session. 3. The system of claim 1, wherein the parameter comprises a location of a fiducial marker that provides indication of a location of the target tissue. 4. A system, for treating a target tissue with radiation, comprising:a radiation source that emits x-ray radiation during a treatment session and a collimator that collimates the emitted x-ray radiation into a x-ray beam having a cross-sectional dimension of less than about 6 mm as the beam exits the collimator;a mapping module that repeatedly maps a location of the target tissue to a coordinate system during the treatment session;a movement module that directs the emitted x-ray radiation along a trajectory that is based, at least in part, on at least one mapped location of the coordinate system; anda targeting module that emits a target light that indicates an approximate center of a beam spot of the x-ray beam. 5. The system of claim 4, further comprising a radiation source mover that moves the radiation source relative to the target tissue to direct the emitted x-ray radiation toward the target tissue. 6. The system of claim 4, wherein the radiation source is configured to be stationary relative to a position of the target tissue during the treatment session. 7. The system of claim 4, further comprising a system shut-off that reduces or ceases emission of radiation when the target tissue is not in a path of the collimated beam. 8. The system of claim 4, wherein the target light comprises laser light. 9. A method, of applying x-ray radiation to target tissue, comprising:obtaining imaging data indicative of a target tissue;identifying, based on the imaging data, a location of the target tissue;repeatedly mapping the location of the target tissue in the coordinate system, thereby producing mapped locations of the target tissue in the coordinate system;positioning, based on the mapped locations of the target tissue in the coordinate system, an x-ray collimator that directs an x-ray beam to the target tissue; andemitting the x-ray beam from the collimator to the target tissue, the x-ray beam having an energy of from about 1 KeV to about 500 KeV;wherein the x-ray beam has a dose distribution at a beam spot in a plane at the target tissue, such that a dose of the x-ray beam at a region within the plane and outside the beam spot is less than about 20% of a dose at a centroid of the beam spot. 10. The method of claim 9, further comprising making an incision in tissue overlying the target tissue, prior to emitting the x-ray beam toward the target tissue. 11. The method of claim 9, wherein positioning the x-ray collimator further comprises placing a probe at or adjacent the target tissue. 12. The method of claim 9, wherein the target tissue is located in a head of a patient. 13. The method of claim 9, wherein the target tissue is located in the vasculature of a patient. 14. The method of claim 9, wherein the target tissue comprises peripheral vasculature. 15. The method of claim 9, wherein the target tissue is located in the heart of a patient. 16. The method of claim 9, wherein the target tissue is located in the gastrointestinal tract of a patient. 17. The method of claim 9, wherein the target tissue comprises at least one of the colon and the rectum of a patient. 18. The method of claim 9, wherein a tumor comprises the target tissue. 19. The method of claim 9, wherein the target tissue is located in a breast of a patient. 20. The method of claim 9, wherein the target tissue comprises musculoskeletal tissue. 21. The method of claim 9, wherein the target tissue comprises at least one of the liver and the spleen of a patient. 22. The method of claim 9, wherein the beam spot has a cross-sectional dimension smaller than about 1 mm. 23. The method of claim 9, wherein the beam spot has a diameter of between about 1 mm and about 5 mm. 24. The method of claim 9, wherein the x-ray beam comprises alternating regions of higher intensity and lower intensity. 25. The method of claim 9, further comprising making an incision in tissue overlying the target tissue, prior to emitting the x-ray beam toward the target tissue. 26. The method of claim 9, further comprising positioning the target tissue in or on a holding module, wherein the holding module holds the target tissue substantially stationarily while the location of the target tissue is mapped in the coordinate system.
	abstract	A tomography apparatus for readily imaging an object while reducing radiation exposure doses includes a filter that adjusts distribution of a radiation dose transmitted therethrough from a radiation source, a radiation detection unit that detects a radiation dose transmitted through the filter and through an object, a holder that holds the object, an acquisition unit that acquires information about the holder, and a control unit that controls the distribution of the transmitted radiation does according to the information about the holder acquired by the acquisition unit.
	abstract	In an imaging system employing a multifocal collimator, displaying an image. Framing an event stream into a first buffer. Mapping each first buffer bin to a bin of each of a normalization buffer and a count buffer. Normalization buffer and count buffer are the same dimension. First buffer bins correspond to normalization buffer bins and the count buffer bins such that geometric distortion from the multifocal collimator is substantially reduced. The value of each normalization buffer bin corresponds to the quantity of corresponding first buffer bins corresponding to that normalization buffer bin, and a value of each count buffer bin corresponds to total counts of the one or more of the first buffer bins corresponding to the each count buffer bin. Determining an updated image as the ratio of the values of count buffer bins to the normalization buffer bins. Displaying an image as a function of the updated image.
047972475	summary	CROSS-REFERENCE TO RELATED APPLICATION Application Ser. No. 510,491, filed concurrently herewith to Ronald M. Blaushild et al. for "Thermal Insulation of Nuclear Reactor", assigned to Westinghouse Electric Corporation is incorporated herein by reference. BACKGROUND OF THE INVENTION This invention relates to nuclear reactors and has particular relationship to such reactors including a thermal insulating shield. A nuclear reactor, particularly of the pressurized light-water type, has a pressure vessel including a generally cylindrical body and a dome-shaped head. The head is removable for refueling and other services. To conserve the thermal energy developed in the reactor, it is provided with a thermal shield. The shield extends about the body and over the entire closure head. Part of the shield that covers the top of the head is removable as part of the head. Other parts of the shield for the head must be removed to afford access to unscrew the studs to remove the head. In accordance with the teachings of the prior art, the thermal insulation on the head includes a plurality of mating pads which extend over at least a portion of its outer surface. When the head is to be removed, the pads are separately removed from the head. The removal is effected manually usually by lifting the pads one-by-one from the head. This process is time consuming and requires that personnel be exposed to radiation. It is an object of this invention to overcome the drawbacks and disadvantages of the prior art and to provide thermal insulation for the head of a nuclear reactor which shall be readily removable by remote control, without exposure of personnel to radiation, to permit removal or replacement of the head. SUMMARY OF THE INVENTION In accordance with this invention, a nuclear reactor is provided whose head is thermally insulated by a shield including a frame insulating material from which panels of insulating material extend pivotally. The panels are pivoted at or near the top of the frame between a generally horizontal position and a retracted position. In the horizontal position, the panels mate and shield the head thermally. In the retracted position, the panels permit removal or replacement of the head. The panels are pivoted between the two positions by a mechanism or linkage which is actuable remotely.
	description	The container of the present invention may be used for storage and transportation of one or more magazines housing radioactive materials. Nonetheless, the structures and characteristics of the invention are equally applicable to the storage and transport of other types of devices including radioactive material, such as preloaded needles as well. Specific embodiments of the present invention, as will be illustrated further in FIGS. 1-7, provide a container for the storage and transportation of magazines containing radioactive material. Radioactive seeds, which are used in the treatment of tumors and other medical problems, are often housed in magazines which generally contain a plurality of such seeds. The magazines function to both contain the seeds and to ease their loading into the applicators used to introduce the seeds into the human body. Such magazines typically dispense one seed at a time in a predetermined manner and orientation which facilitates the loading of such seeds into their applicators for use. One such magazine is available from Mick Radio and is described in U.S. Pat. No. 5,860,909. Another is illustrated in FIGS. 1-7 herein. The invention is generally applicable to a variety of such magazines, as well as other devices containing radioactive material. FIGS. 1 and 2 illustrate a first embodiment of a container 2 according to the invention for storing and transporting one or more magazines containing radioactive materials. Container 2 includes a lower portion 4 and an upper portion 6, which may be separated to allow access to the inside of container 2. Lower portion 4 may include a conventional radiation shielding material, such as lead, steel or other appropriate materials. In a more preferred embodiment of the invention, both upper portion 6 and lower portion 4 of container 2 include a radiation shielding material. Upper portion 6 and lower portion 4 of container 2 may be joined together by a closure 10. The closure may be a friction fit, a mechanical fastener, threads, a slip-fit, or other similar closing structures. The container may also be taped closed on the outside to provide additional security, and such tape may also contain a radiation shielding material. A basket 7, which serves as a holder for magazines 8, may be located within lower portion 4 of container 2. Basket 7 also functions to isolate magazines 8 from contact with the lower portion 4 of container 2. Such isolation may be required depending on the materials used to fabricate lower portion 4 of container 2. Basket 7 may optionally include a handle 12 to facilitate removal of basket 7 from container 2. Magazines 8 may be placed in recesses 16 of basket 7 which are defined by sleeves 14 which function to surround and laterally support magazines 8. A drain port 18 may be located in the bottom of each recess 16 of basket 7 to allow liquids to drain from recesses 16 in order to facilitate cleaning and sterilization of basket 7 including the inner surfaces of sleeves 14. Recesses 16 may be customized to conform to the specific shape of the magazines 8 or to help properly align magazines 8 in recesses 16 during insertion, such as, for example by providing a narrower section of recesses 16 formed by shoulder 20 in sleeve 14. Magazines 8 may optionally be secured in recesses 16 by threads 13 on magazines 8 which mate with threads 17 in recesses 16. Sleeves 14 are preferably connected to one another by ribs 22 which, optionally, may all connect at a handle 12 if such is included as part of basket 7. Secondary ribs 23 may also be provided to enhance the mechanical integrity of basket 7. In a preferred embodiment of the invention, basket 7 is made of a sterilizable material. Basket 7 may be removed from container 2, and be separately placed in a sterilization unit, such as an autoclave or chemical disinfection, chemical sterilization or other conventional means of sterilization, or may be sterilized while within lower portion 4 of container 2. Thus, basket 7 may act as a simple transfer device for handling one or more magazines 8 prior to, and during use. Basket 7 may be injection molded from, for example, nucleated polypropylenes, polysulfones, polycarbonates, high temperature acrylics or polyether sulfones. Other conventional materials and/or methods of making basket 7 may also be employed. In another embodiment, container 2 may itself be sterilized, such as by an autoclave or other conventional means, thereby allowing sterilized magazines 8 to be sterilized directly in container 2 or stored or transported in container 2 in sterilized condition. Referring still to FIGS. 1-2, upper portion 6 may also include a shoulder 24 which may be used to substantially secure magazines 8 against vertical movement in basket 7, when upper portion 6 and lower portion 4 are associated to form container 2. As described previously, magazine 8 may comprise a casing having an upper surface 11. When a magazine 8 is placed into recess 16 of basket 7, located in lower portion 4 and upper portion 6 is placed on lower portion 4 to enclose basket 7, shoulder 24 is positioned closely adjacent to, or in abutment with, the upper surface 11 of each magazine S. Shoulder 24 thereby substantially secures magazine 8 in the vertical direction to minimize or prevent vertical movement of magazines 8 during transport. Basket 7 of container 2 allows magazines 8 to be transported and sterilized easily, e.g., within a medical facility. Ease of transportation helps to minimize handling, thereby reducing the potential for exposure to radiation. A light-weight basket 7 also reduces the overall weight of container 2, thereby reducing transportation costs and facilitating the handling of container 2. To use the container shown in FIGS. 1-2, one or more magazines 8 containing radioactive material are placed in recesses 16 of basket 7. Basket 7 is located in lower portion 4 of container 2. In this configuration, without upper portion 6, the radiation shielding material included in lower portion 4 may cooperate with radiation shielding 9 of magazine 8 to together contain a substantial portion of radiation emitted by the radioactive material when the magazine 8 is the type which includes its own radiation shielding material. Thus, the potential for exposure to radiation, even with the container 2 in the open position, is minimized due to either the radiation shielding of the lower portion 4 of container 2, or due to the cooperative shielding provided by the radiation shielding 9 of magazine 8 and the lower portion 4 of container 2. Magazines 8 may be fitted into recesses 16 of lower portion 4 by a friction fit, mechanical fastener, slip-fit or by a thread 17, provided on the inner surface of the sleeve 14 and the cooperating thread 13 provided on the outer surface of magazine 8. Subsequently, upper portion 6 is fitted onto lower portion 4 such that the closure 10 holds upper portion 6 in place on lower portion 4. In this manner, shoulder 24 is positioned closely adjacent to, or in abutment with, upper surface 11 of magazine 8 to thereby minimize or prevent vertical movement of magazine 8 within recess 16 during storage and transport. Upper portion 6 may also optionally include a radiation shielding material to provide additional shielding against radiation emitted in the vertical direction. FIG. 5 illustrates another embodiment of a container 102 of the present invention, and FIGS. 3 and 4 illustrate a tray 108 to be used in the container 102 illustrated in FIG. 5. Container 102 of FIG. 5 comprises a lower portion 104 and an upper portion 106. Lower portion 104 preferably includes a conventional radiation shielding material, such as lead, steel or other appropriate materials. In a more preferred embodiment of the invention, both upper portion 106 and lower portion 104 of container 102 include a radiation shielding material. Upper portion 106 and lower portion 104 may be joined by a closure 107 such as a friction fit, a mechanical fastener, a slip-fit, threads, or other similar closing structures. Tape may be provided on the outside of container 102 to ensure that the container 102 is not opened during transport Tray 108 is designed to be placed within container 102. Tray 108 includes a plurality of recesses 112 for holding magazines 8. Recesses 112 are preferably generally cylindrical in shape and more preferably are designed to provide a friction fit with at least a portion of a magazine 8. Most preferably, recesses 112 are shaped to provide a form fit with magazines 8. Recesses 112 hold magazines 8 by limiting their lateral movement within container 102. Tray 108 may be vacuum-formed, molded, or injection molded, for example, and is preferably made from plastic or other suitable material. Tray 108 may be made from, for example, nucleated polypropylenes, polysulfones, polycarbonates, high temperature, acrylics or polyether sulfones. Tray 108 stabilizes magazines 8 during shipment and isolates magazines 8 from direct contact with container 102. In a preferred embodiment of the invention, tray 108 is sterilizable. As such, tray 108 may be placed separately from container 102 in a sterilization unit, such as an autoclave or other conventional sterilization means, to facilitate handling and sterilization of the magazines 8 or may be sterilized together with container 102. In another embodiment of the invention, tray 108 may include a film 114 to hold magazines 8 in tray 108 against vertical movement. More preferably, film 114 seals tray 108 to permit shipment of sterilized magazines 8. Alternatively, film 114 may include a radioactive shielding material and may optionally provide a seal for tray 108 as well. Film 114 may be any appropriate material, such as foil, a laminate, or the like. In another embodiment, the entire container 102 may be sterilized and sealed in any conventional manner, thereby allowing sterilized magazines 8 to be transported in tray 108 without requiring film 114 to seal the tray 108. Lower portion 104 of container 102 may optionally include a shelf 116 upon which a peripheral flange 109 of tray 108 may rest when tray 108 is placed within lower portion 104 of container 102. Subsequently, when upper portion 106 of container 102 is put into place to close container 102, peripheral flange 109 is pinched between shelf 116 of lower portion 104 and a mating surface 117 of upper portion 106 to thereby substantially secure tray 108 in lace and prevent movement and shifting of tray. 108 during transport of container 102. Peripheral flange 109 may extend for only a portion of the periphery of tray 108 or around the entire periphery. Tray 108 of container 102 allows a plurality of magazines 8 to be removed from container 102 and transported and sterilized more easily than if the magazines 8 remained in container 102, e.g., within a medical facility. Additionally, the weight of the container 102 is reduced relative to the commercially available container, thereby reducing transportation costs and facilitating the handling of container 102. To use container 102, magazines 8 are inserted into recesses 112 of tray 108 as shown in FIG. 3. Tray 108 is positioned in lower portion 104 of container 102 as shown in FIG. 5. Radiation shielding provided by lower portion 104 which may include a radiation shielding material may act in cooperation with radiation shielding material 9 of magazine 8 to contain a substantial portion of the radiation emitted by the radioactive material contained in magazine 8. In this manner, the container shown in FIGS. 3-5 minimizes the potential for exposure to radiation even when the container 102 is open. For storage and/or transport, upper portion 106 of container 102 is placed atop lower portion 104 as shown in FIG. 5 with closure 107 holding upper portion 106 in place on lower portion 104. As can be seen in FIG. 5, upper portion 106 preferably pinches flange 109 of tray 108 atop shelf 116 of lower portion 104 in order to firmly secure tray 108 in position within container. 102. Upper portion 106 may optionally include a radiation shielding material to provide additional shielding against radiation emitted in the vertical direction. FIGS. 6 and 7 illustrate another embodiment of a container 202 of the present invention. Container 202 comprises a lower portion 204 and an upper portion 206. Lower portion 204 includes a conventional radiation shielding material, such as lead, steel or other appropriate materials. In a more preferred embodiment of the invention, upper portion 206 of container 202 also includes a radiation shielding material. Alternatively, upper portion 206 may be made of a material which does not act as a shield against radiation, such as a light-weight plastic, or other appropriate material. Upper portion 206 may be made from, for example, nucleated polypropylenes, polysulfones, polycarbonates, high temperature acrylics or polyether sulfones. Use of plastic in upper portion 206 further reduces the total weight of the container 202, with a possible weight reduction 40-45%, versus use of lead. Reduced weight reduces costs for shipping and transporting container 202 and makes it easier to handle. Upper portion 206 and lower portion 204 may be joined by a closure 213 such as a friction fit, a mechanical fastener, threads, a slip-fit, or other similar closing structures and may be taped closed to ensure that the container 202 is not opened during transport. Lower portion 204 includes recesses 210 to receive magazines 8. Recesses 210 are preferably cylindrical in shape and more preferably recesses 210 provide a friction fit with at least a portion of a magazine 8 or form fit with the entire magazine 8. In one embodiment of the invention, it may be desirable to isolate magazines 8 from lower portion 204 through use of a plastic sleeve (not shown) or other appropriate device such as those described in the other embodiments of the present invention. A plastic sleeve may be placed over magazines 8, or may be placed in recesses 210. Upper portion 206 of container 202 includes a plurality of holders 212 formed by projections 214, each holder 212 designed to receive an end of a magazine 8. Upper portion 206 and lower portion 204 are manufactured so that holders 212 align with recesses 210 when the container 202 is closed, thereby allowing each magazine 8 to be secured against lateral movement by a combination of the action of holders 212 and recesses 210. Moreover, projections 214 of upper portion 206 can be fabricated to be closely adjacent to, or in abutment with, upper surfaces 11 of magazine 8 when container 202 is closed to further secure magazines 8 against vertical movement in container 202. Upper portion 206 may be placed on lower portion 204, thereby enclosing magazines 8 within container 202. More specifically, magazines 8 are preferably enclosed within holders 212 and recesses 210 to prevent lateral movement thereof as shown in FIG. 7. To use the container shown in FIGS. 6-7, magazines 8 are placed into recesses 210 of lower portion 204 of container 202 as shown in FIG. 7. In this position, without upper portion 206 of container 202, the radiation shielding material which may be contained in lower portion 204 may cooperate with the radiation shielding material 9 of magazines 8 to together contain a substantial portion of the radiation emitted by the radioactive material contained in magazines 8. In this manner, the potential for exposure to radiation is minimized, even when container 202 is open. For storage and shipment, upper portion 206 of container 202 is placed atop lower portion 204 shown in FIG. 7 and the closure 213 maintains upper portion 206 in position on lower portion 204. Upper portion 206 provides vertical and additional lateral stability to magazines 8 by virtue of holders 214 which limit lateral movement of magazines 8 and which are closely adjacent to, or in abutment with, upper surface 11 of magazines 8 to thereby also limit vertical movement thereof. Upper portion 206 may optionally include a radiation shielding material to provide additional shielding against radiation emitted in the vertical direction. According to an alternative embodiment of the present invention, lower portion 204 and upper portion 206 may be placed in a sterilization unit, such as an autoclave or other conventional sterilization means and subsequently sealed in any conventional manner. This allows container 202 to store and transport magazines 8 in a sterilized condition. These and other embodiments and uses of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. For example, containers may be altered to accept magazines of various sizes and shapes. The specification and examples should be considered exemplary only. The scope of the invention is only limited by the claims appended hereto.
	claims	1. A method, comprising:activating a heating system prior to withdrawing one or more control rods associated with an initialization of a reactor core to achieve reactor criticality, wherein the reactor core is at least partially surrounded by a primary coolant that feeds into a riser located in a nuclear reactor vessel;introducing heat to the primary coolant, in response to activating the heating system, at one or more insertion points located within the riser at an elevation above the reactor core;circulating the primary coolant through the reactor core while the primary coolant is heated to an initial operating temperature; andwithdrawing, at least partially, the one or more control rods from the reactor core after the primary coolant is heated to the initial operating temperature. 2. The method of claim 1, further comprising deactivating the heating system, wherein the one or more control rods are withdrawn from the reactor core after the heating system is deactivated. 3. The method of claim 2, further comprising reactivating the heating system to control a reactor operating pressure after the reactor core has achieved criticality. 4. The method of claim 2, wherein the heating system is deactivated after the primary coolant has achieved an operating temperature associated with a low power steady state condition of the reactor core. 5. The method of claim 1, wherein the heating system comprises one or more electrical heaters located above the reactor core, and wherein the heaters are configured to generate the heat introduced into the primary coolant. 6. The method of claim 1, wherein the heating system introduces the heat to the primary coolant while the one or more control rods are completely inserted in the reactor core. 7. The method of claim 1, wherein the reactor core is located in the nuclear reactor vessel, wherein the heating system comprises one or more heaters located external to the nuclear reactor vessel, and wherein the one or more heaters are configured to heat liquid. 8. The method of claim 7, wherein the heating system further comprises one or more nozzles operatively connected to the one or more heaters, and wherein the one or more nozzles introduce the heat via the heated liquid inserted directly into the primary coolant. 9. The method of claim 1, wherein the heating system comprises one or more nozzles that introduce the heat via heated liquid inserted directly into the primary coolant located within the riser. 10. The method of claim 9, wherein the heating system comprises one or more heaters located in an upper head of the nuclear reactor vessel, and wherein the one or more nozzles are at least partially located within the riser and are operably connected to the upper head via one or more extraction lines. 11. The method of claim 1, further comprising removing heat from the primary coolant with a heat exchanger, wherein the primary coolant is circulated through the reactor core in response to a difference in liquid density of the primary coolant in the riser and at the heat exchanger prior to withdrawing the one or more control rods from the reactor core. 12. The method of claim 11, wherein the heat exchanger is located above the elevation where the heat is introduced into the riser. 13. A method, comprising:activating a heating system prior to initializing a reactor core, wherein the reactor core is at least partially surrounded by a primary coolant that feeds into a riser located in a nuclear reactor vessel, and wherein at least a portion of the riser is located at an elevation that is above the reactor core;introducing heat to the primary coolant, in response to activating the heating system, at one or more insertion points located within the portion of the riser;circulating the primary coolant through the reactor core while the primary coolant is heated to an initial operating temperature; andinitializing the reactor core after the primary coolant is heated to the initial operating temperature, to achieve reactor criticality. 14. The method of claim 13, wherein the reactor core is initialized by at least partially withdrawing one or more control rods from the reactor core. 15. The method of claim 14, wherein the heat is introduced to the primary coolant prior to withdrawing the one or more control rods from the reactor core. 16. The method of claim 13, further comprising:heating the primary coolant to an initial operating temperature prior to initializing the reactor core; anddeactivating the heating system after the primary coolant is heated to the initial operating temperature. 17. The method of claim 16, wherein the reactor core is initialized after deactivating the heating system. 18. The method of claim 16, wherein the reactor core is initialized prior to deactivating the heating system. 19. The method of claim 13, further comprising removing heat from the primary coolant by a heat sink to create a natural circulation of the primary coolant through the reactor core, wherein the elevation that the heat is introduced into the riser is located between the heat sink and the reactor core. 20. The method of claim 13, wherein the nuclear reactor vessel comprises a pressurized reactor vessel, wherein the reactor core is located in the pressurized reactor vessel, and wherein the heating system comprises one or more heaters located external to the pressurized reactor vessel.
	abstract	A fuel assembly has a regular dodecagon fuel rod arrangement with a single fuel rod provided to each apex of a regular dodecagon having lines of length A. Assuming a direction within a horizontal plane is transverse, and a direction perpendicular to the transverse direction is longitudinal, regular dodecagon fuel rod arrangements are arranged in regular intervals in the transverse direction and the longitudinal direction. In the transverse direction, two adjacent regular dodecagon fuel rod arrangements are arranged having opposing two sides of the regular dodecagons parallel to each other with the distance of mA, wherein m is a nonnegative integer, apart from each other. With respect to the longitudinal direction, two adjacent regular dodecagon fuel rod arrangements are arranged so that the opposing two sides of the regular dodecagons are parallel to each other with the distance of nA, wherein n is a nonnegative integer, apart from each other.
	abstract	An apparatus for reducing the influence by scatter rays and improving image quality of a tomographic image. The apparatus includes an X-ray detector and a calculation/control apparatus for generating tomographic image data for a tomographic image of the subject based on the projection data. The X-ray detector includes a plurality of detector channels for detecting the radiation, extending in a two-dimensional manner in two arrangement directions, i.e., in channel and column directions, the channel direction being contained in a plane of rotation of the X-ray source, the column direction being orthogonal to the channel direction and aligned along the axis of rotation; and collimators for confining an angle at which X-rays impinge upon the detector channels, provided at borders between the detector channels adjoining in the column direction.
	description	This application is a continuation of International Application No. PCT/JP2003/004462, having an international filing date of Apr. 8, 2003, which designated the United States, the entirety of which is incorporated herein by reference. This application also claims the benefit of Japanese Application No. 2002-105742, filed Apr. 8, 2002, Japanese Application No. 2002-253284, filed Aug. 30, 2002, and Japanese Application No. 2002-253285, filed Aug. 30, 2002, the entireties of which are incorporated herein by reference. The present invention relates to a material including a beryllium intermetallic compound applied to nuclear fusion reactors and more specifically relates to a material including a beryllium intermetallic compound applied to blankets and plasma facing members of nuclear fusion reactors, which are exposed to neutrons and heat generated by plasma in the nuclear fusion reactors. A Tokamak nuclear fusion reactor generates ring-like plasma so as to produce nuclear fusion reaction therein by means of electromagnetic coils arranged like a circumference. The ring-like plasma radiates neutrons and radiant heat and hence blankets and plasma facing members are disposed so as to enclose the plasma. The blanket is essentially composed of neutron multiplier members for further breeding neutrons from the radiated neutrons, tritium multiplier members for breeding tritiums from the multiplied neutrons and cooling water circulation system for cooling these members so as to extract heat. The plasma facing members are disposed within the blankets so as to protect the blankets from the plasma. To the blankets and the plasma facing members, it is necessary to apply materials of reduced susceptibility of swelling, which is defined as volumetric expansion results from bubbles generated in the materials caused by exposure to radiation. Furthermore, the materials are required not to absorb a large amount of tritiums so as to effectively collect the tritiums. Among materials for the blankets, the material applied to the neutron multiplier members is required to have a large reaction cross section with respect to the neutrons. Beryllium formed in small pebbles has been conventionally employed. As the material applied to the plasma facing member, it is necessary to be less susceptible of sputtering erosion by the plasma and has small radiation loss in a case where contamination into the plasma caused by the sputtering occurs. Tungsten, beryllium and carbon or carbon composite material has been hitherto under examination for application. Beryllium has relatively excellent properties with respect to any of the aforementioned applications. Beryllium would not cause any trouble in a case where the temperature is below about 400 degree C. and the exposure to the neutrons is below about 3000 appmHe, but might give rise to risks of hydrogen generation and consequent hydrogen explosion led from an oxidation reaction by a high-temperature water vapor in a case where the temperature in use is beyond about 600 degree C. and any accident such as breaking of cooling tubes is happened. Moreover, beryllium has a problem of reactivity with a stainless steel ISO-19N of which the blanket is made. Furthermore, there is a possibility that large swelling of beryllium leads to breaking of a vessel and such accidents. On the other hand, as the plasma facing material, beryllium is more susceptible of sputtering erosion than tungsten, carbon and carbon composite materials. Therefore any material capable of use in higher temperature and less susceptible of sputtering erosion is expected. The present invention is accomplished in view of the above problem and intended for providing a material for nuclear fusion reactors being capable of use in higher temperature and less susceptible of sputtering erosion. The present inventors paid their attention to intermetallic compounds of beryllium with Ti, V, Zr, Nb, Ta, Mo, W or Y as also having the excellent properties of beryllium and additionally having a high-temperature property and being less susceptible of sputtering erosion. Such beryllium intermetallic compounds are generally brittle and hence uneasy to be machined and handled. The present inventors invented that brittleness of the beryllium intermetallic compounds can be overcome by means of dispersing the compounds in another metal or making composites with another intermetallic compounds and then reached to the present invention of the material practically applied to the nuclear fusion reactors. According to a first aspect of the present invention, a material for a nuclear fusion reactor is an alloy including at least one beryllium intermetallic compound phase. The beryllium intermetallic compound phase preferably consists of a compound of Be with one or more elements selected from the group of Ti, V, Zr, Nb, Ta, Mo, W and Y. More preferably, a matrix phase thereof consists of one or more metals selected from the group of Be, Zr, Ti and V. Still preferably, a volumetric ratio of the beryllium intermetallic compound phase is 50 to 99%. The material for the nuclear fusion reactor is preferably applied to a neutron multiplier material. According to a second aspect of the present invention, a material for a nuclear fusion reactor consists one essentially of one or more substances selected from the group of Be12M or Be13M and Be17M2; or two or more substances selected from the group of Be12M or Be13M, Be17M2, Be and M, wherein M is a metal element selected from the group of Ti, V, Mo, W, Zr, Nb and Ta, and an average content x of M is in a range of 2.0≦x≦15.0 (at %), or preferably 7.7<x<10.5 (at %). The material for the nuclear fusion reactor consisting of beryllium intermetallic compounds is preferably applied to a nuclear multiplier material, and further applied to a plasma facing material as well. Preferably, the material for the nuclear fusion reactor of any of the above aspects is produced by casting or sintering and a crystal particle size is no more than 50 μm. A neutron multiplier material according to the present invention includes metallic phases interposed between the beryllium intermetallic compound phases so that the metallic phases adhere the beryllium intermetallic compound phases and accordingly whole body of the neutron multiplier material gets higher ductility, which leads to advantages of machinability and easiness of handling. To the beryllium intermetallic compound phases of the present invention, compounds of beryllium with Ti, V, Zr, Nb, Ta, Mo, W or Y, listed below as examples, are specifically preferably adapted. Be12Ti (1550 degree C.), Be17Ti2 (1650 degree C.), Be12V (1700 degree C.), Be13Zr (1800 degree C.), Be17Zr12 (1600 degree C.), Be12Nb (1700 degree C.), Be17Nb2 (1800 degree C.), Be12Ta (1850 degree C.), Be17Ta2 (1970 degree C.), Be12Mo (1700 degree C.), Be12W (1750 degree C.), Be22W (1600 degree C.), Be13Y (1920 degree C.), where the values put in parentheses respectively indicate melting points thereof. Any of the aforementioned beryllium intermetallic compounds has a high melting point and high oxidation resistance so as to indicate excellent heat-resistance. While such beryllium intermetallic compounds are slightly inferior in the neutron multiplying effect to metallic beryllium, tritium inventory and reactivity with structural members of the blanket are relatively lower. Particularly, anti-swelling property thereof is exceedingly good. Moreover, to the metallic phase of the present invention, any metal selected from the group of Be, Zr, Ti and V is preferable. Because these metals effectively go around and fill gaps among the beryllium intermetallic compounds and hence efficiently increase ductility of the multiplier material including the beryllium intermetallic compounds as a whole. Particularly, Be and Zr are further preferably applied to the metallic phase as having a neutron multiplying function as well. Furthermore, a ratio of the beryllium intermetallic phase in such a neutron multiplying material is favorably set about 50 through 99% in volumetric ratio. Because, provided that the mixing ratio does not reach 50 vol %, reactivity with vapor and such and swelling are remarkably increased and, provided that the mixing ratio exceeds 99 vol %, the effect of increasing ductility by the metallic phase is decreased so that reduction of the machinability and the easiness of handling is unavoidable. Size of pebbles of the neutron multiplier material according to the present invention is preferably set about 0.1 through 3.0 mm in average particle diameter. Out-of-sphericity thereof is preferably set no more than 0.5 times the particle diameter. Size of the beryllium intermetallic compound phases included in the neutron multiplier material is preferably set no more than about 100 μm in circle-equivalent diameter. Furthermore, concentration of Fe included in the neutron multiplier material is preferably set no more than about 0.4 mass % and concentration of mixed oxides is preferably set no more than about 5.0 mass %. Production methods of the neutron multiplier material according to the present invention will be described hereinafter. The present invention does not require particular limits to the production method, however, a rotating electrode method and a powder metallurgy method, both of which are previously publicly known, are preferably applied. Rotating Electrode Method To employ the rotating electrode method to produce neutron multiplier material pebbles, first of all, preparing consumable electrode is necessary. To prepare the consumable electrode, providing metals, weights of which correspond to a ratio satisfying a weight ratio of the respective constituents of the desired intermetallic compound, melting the metals together, casting the mixture and machining the cast into a predetermined electrode shape are accomplished. Next, preparing the neutron multiplier material pebbles from the obtained consumable electrode by means of the rotating electrode method is accomplished. Production conditions on this occasion are not particularly restricted, however, preferable conditions are described as follows. atmospheric gas pressure: 500 to 12000 Torr arc current: 100 to 1000 A rotation speed of the consumable electrode: 4 to 1000 m/sPowder Metallurgy Method To produce neutron multiplier material pebbles by means of this method, mixing intermetallic compound powder prepared to be a desired compositional ratio and metal powder having a weight so as to be a predetermined ratio of metal phase included in the neutron multiplier material, filling the mixed powder in spherical metal molds or such, forming green compacts in spherical shapes by means of cold pressing or such and sintered to be pebbles in a vacuum atmosphere are accomplished. FIG. 1 shows a micro-metallograph of a neutron multiplier material obtained from the aforementioned rotating electrode method. The neutron multiplier material is an example which includes Be12Ti (95% in volumetric ratio) as a beryllium intermetallic compound phase and Be as a metallic phase. As shown in the drawing, it is clearly understood that an α-Be phase uniformly surrounds grains of Be12Ti according to the present invention. Neutron multiplier materials respectively including beryllium intermetallic compounds and metals, compositions of which are described in Table 1, are produced by means of the rotating electrode method or the powder metallurgy method. Particle sizes of the obtained neutron multiplier materials are 0.7 to 1.3 mm. Results of evaluation about a neutron multiplying effect, an anti-swelling property, a ductility, a reactivity with the structural member, a reactivity with the vapor, a tritium inventory and a heat conductivity of each of thus obtained neutron multiplier materials are described in Table 2. In addition, the respective properties are evaluated by the following procedures. Neutron Multiplying Effect A neutron multiplying effect is evaluated as a relative ratio to the neutron multiplying effect of the conventional metallic beryllium pebbles as 10, considering the neutron reaction cross section, the neutron absorption cross section and the neutron capture cross section of each of the constituent elements. Anti-swelling Property An amount of swelling is measured in a condition that neutrons are irradiated to the test piece so as to generate 4000 ppm of He therein at 700 degree C. and the anti-swelling property is evaluated on a degree of swelling as three levels of SMALL (the swelling amount is not more than 0.5 vol %), MIDDLE (more than 0.5 vol % and not more than 3.0 vol %) and LARGE (more than 3.0 vol %), where the swelling amount is measured by volumetric change rate (ΔV/V times 100 (%)). Ductility A compression test is accomplished with a test piece of approximate 1 mmΦ pebble in diameter in a condition of compression speed: 0.2 mm/min and ductility is evaluated on shapes after the test. Reactivity with the Structural Members A reactivity test with stainless steel in a He atmosphere of 6N for 800 to 1000 h is accomplished and the reactivity is evaluated on a degree of reaction with the structural members as three levels of SMALL (reaction layer: no more than 50 μm), MIDDLE (reaction layer: more than 50 μm and no more than 200 μm) and LARGE (reaction layer: more than 200 μm). Reactivity with the Vapor A reactivity test with the water vapor at 800 degree C. is accomplished and the reactivity is evaluated on a degree of reaction with the water vapor as three levels of SMALL (rarely oxidized), MIDDLE (oxidized) and LARGE (destructed by oxidation). Tritium Inventory Tritium inventory is evaluated on an amount of tritium of the test piece accomplished of the swelling test, measured by the temperature-programmed desorption method. Specifically, the tritium inventory is evaluated on a degree of the tritium inventory as three levels of SMALL (extremely small amount), MIDDLE (some amount) and LARGE (large amount). TABLE 1MeltingIntermetallicMetallicProductionpointNocompound(vol %)phase(vol %)method(° C.)1Be12Ti100——rotating1550electrode2↑95Be5↑15303↑93Be7↑15004↑90Be10powder1450metallurgy5↑85Be15↑14006↑55Be45↑13507Be17Ti290Be10↑15508Be12V100——↑17009↑95Be5rotating1670electrode10↑93Be7↑165011↑90Be10powder1600metallurgy12↑85Be15↑155013Be13Zr93Be7rotating1720electrode14↑90Be10powder1700metallurgy15Be17Zr290Be10↑150016Be12Nb90Be10↑160017Be17Nb290Be10↑170018Be12Ta93Be7rotating1770electrode19↑90Be10powder1750metallurgy20Be17Ta290Be10↑190021Be12Mo95Be5rotating1650electrode22↑90Be10powder1600metallurgy23Be12W95Be5rotating1700electrode24↑90Be10powder1650metallurgy25Be22W90Be10↑150026Be13Y90Be10↑180027Be12Ti90Zr10↑155028↑90Ti10↑155029↑60Ti40↑155030↑90V10↑155031Be12V90Zr10↑155032↑70Zr30↑155033↑90Ti10↑155034↑90V10↑155035Be12Mo90Zr10↑155036↑90Ti10↑155037↑90V10↑155038——Be100rotating1280electrode TABLE 2ReactivitywithReactivityNeutronthewithThermalmultiplyingAnti-swellingstructuraltheTritiumconductivityNo.effectpropertyDuctilitymembersvaporinventory(W/m K)remarks10.90SMALLXSMALLSMALLSMALL40comparativeexample20.92SMALL◯SMALLSMALLSMALL55presentinvention30.92SMALL◯SMALLSMALLSMALL55↑40.93MIDDLEΔMIDDLEMIDDLEMIDDLE65↑50.94MIDDLEΔMIDDLEMIDDLEMIDDLE70↑60.95MIDDLE◯LARGELARGELARGE90↑70.85MIDDLEΔMIDDLEMIDDLEMIDDLE70↑80.92SMALLXSMALLSMALLSMALL40comparativeexample90.93MIDDLE◯MIDDLEMIDDLEMIDDLE45presentinvention100.94MIDDLE◯MIDDLEMIDDLEMIDDLE45↑110.94MIDDLEΔMIDDLEMIDDLEMIDDLE55↑120.94MIDDLEΔMIDDLEMIDDLEMIDDLE65↑130.85MIDDLEΔMIDDLEMIDDLEMIDDLE70↑140.88MIDDLEΔMIDDLEMIDDLEMIDDLE70↑150.80MIDDLEΔMIDDLEMIDDLEMIDDLE70↑160.75MIDDLEΔMIDDLEMIDDLEMIDDLE50↑170.70MIDDLEΔMIDDLEMIDDLEMIDDLE65↑180.80MIDDLEΔMIDDLEMIDDLEMIDDLE65↑190.82MIDDLEΔMIDDLEMIDDLEMIDDLE65↑200.78MIDDLEΔMIDDLEMIDDLEMIDDLE65↑210.85SMALL◯SMALLSMALLSMALL50↑220.80MIDDLEΔMIDDLEMIDDLEMIDDLE70↑230.75SMALL◯SMALLSMALLSMALL50↑240.70MIDDLEΔMIDDLEMIDDLEMIDDLE70↑250.75MIDDLEΔMIDDLEMIDDLEMIDDLE70↑260.90MIDDLEΔMIDDLEMIDDLEMIDDLE70↑270.78SMALLΔSMALLSMALLSMALL70↑280.88SMALLΔSMALLSMALLSMALL70↑290.65SMALL◯MIDDLESMALLSMALL100↑300.88SMALLΔSMALLSMALLSMALL70↑310.78SMALLΔSMALLSMALLSMALL70↑320.50SMALL◯MIDDLESMALLSMALL90↑330.80SMALLΔSMALLSMALLSMALL70↑340.80SMALLΔSMALLSMALLSMALL70↑350.80SMALLΔSMALLSMALLSMALL70↑360.80SMALLΔSMALLSMALLSMALL70↑370.80SMALLΔSMALLSMALLSMALL70↑381.00LARGE⊚LARGELARGELARGE170conventional As shown in Table 2, any of the examples of the present invention is excellent in the ductility and the anti-swelling property and has a proper neutron multiplying effect, a small tritium inventory and small reactivity with the structural members and the vapor. In contrast to this, the comparative examples of No. 1 and No. 8 are poor in the ductility because they consist of 100 vol % of beryllium intermetallic compound. The comparative example of No. 38 is excellent in the neutron multiplying effect and the ductility, because it consists of 100 vol % of metallic beryllium, but is large in the swelling and the tritium inventory and further large in the reactivity with the structural members and the vapor. Cases where the metallic phase is a matrix of the material has been described in the aforementioned first embodiment. The present invention can be embodied with any combinations of distinct beryllium intermetallic compounds. Specifically, substances obtained from mixing and casting a combination of beryllium and titanium so that Be12Ti and Be17Ti2 coexist and are intermixed therein are ascertained to be remarkably improved in ductility as compared with simple substances of Be12Ti and Be17Ti2. A mixing ratio of Be12Ti and Be17Ti2is not particularly limited, however, it is ascertained that the particularly preferable mixing ratios in a range of 10.5 to 2.0, or x in a range of 8.8 to 9.9 at % as described in a ratio x of Ti to Be, give especially excellent results. Next, the present inventors conceived that any elements besides Ti might give similar effects and investigated various elements. As a result, it is ascertained that V, Mo, W, Zr, Nb and Ta give similar effects with Ti. Furthermore, it is ascertained that the mixing ratios of the elements such that beryllium intermetallic compounds of Be12M and Be17M2 (where M is any one element selected from the group of V, Mo, W, Nb and Ta) (however, beryllium intermetallic compounds of Be13Zr and Be17Zr2provided that M is Zr) coexist and are intermixed give excellent results as similar with Ti. Moreover, concerning with metallographic structures of the composite phases of the beryllium intermetallic compounds, it is ascertained to be further advantageous in view of strength and ductility to set grain sizes of cast structures no more than 50 μm and particularly preferably no more than 20 μm. Size of pebbles of the neutron multiplier material according to the present invention is preferably set about 0.1 through 3.0 mm in average particle diameter. Moreover, out-of-sphericity thereof is preferably set no more than 0.5 times the particle diameter. Furthermore, concentration of Fe included in the neutron multiplier material is preferably set no more than about 0.4 mass % and concentration of mixed oxides is preferably set no more than about 5.0 mass %. Next, production methods of the neutron multiplier material according to the present invention will be described hereinafter. The present invention does not require particular limits to the production method, however, a rotating electrode method and a powder metallurgy method, both of which are previously publicly known, are preferably applied. Rotating Electrode Method To employ the rotating electrode method to produce neutron multiplier material pebbles, first of all, preparing consumable electrode is necessary. To prepare the consumable electrode, providing metals, weights of which correspond to a ratio satisfying a weight ratio of the respective constituents of the desired intermetallic compound, melting the metals together, casting the mixture and machining the cast into a predetermined electrode shape are accomplished. Next, preparing the neutron multiplier material pebbles from the obtained consumable electrode by means of the rotating electrode method is accomplished. Production conditions on this occasion are not particularly restricted, however, preferable conditions are described as follows. atmospheric gas pressure: 500 to 12000 Torr arc current: 100 to 1000 A rotation speed of the consumable electrode: 4 to 1000 m/sPowder Metallurgy Method To produce neutron multiplier material pebbles by means of this method, mixing intermetallic compound powder prepared to be a desired compositional ratio and metal powder having a weight so as to be a predetermined ratio of metal phase included in the neutron multiplier material, filling the mixed powder in spherical metal molds or such, forming green compacts in spherical shapes by means of cold pressing or such and sintered to be pebbles in a vacuum atmosphere are accomplished. Neutron multiplier materials respectively including beryllium intermetallic compounds and metals, compositions of which are described in Table 3, are produced by means of the rotating electrode method or the powder metallurgy method. Particle sizes of the obtained neutron multiplier materials are 0.7 to 1.3 mm. Results of evaluation about a neutron multiplying effect, an anti-swelling property, a ductility, a reactivity with the structural member, a reactivity with the vapor, a tritium inventory and a heat conductivity of each of thus obtained neutron multiplier materials are described in Table 4. Ductility A compression test is accomplished with a test piece of approximate 1 mm (pebble in diameter in a condition of compression speed: 0.2 mm/min and ductility is evaluated on a shape after the test. Reactivity with the Structural Members A reactivity test with stainless steel in a He atmosphere of 6N for 800 to 1000 h is accomplished and the reactivity is evaluated on a degree of reaction with the structural members as three levels of SMALL (reaction layer: no more than 50 μm), MIDDLE (reaction layer: more than 50 μm and no more than 200 μm) and LARGE (reaction layer: more than 200 μm). Reactivity with the Vapor A reactivity test with the water vapor at 800 degree C. is accomplished and the reactivity is evaluated on a degree of reaction with the water vapor as three levels of SMALL (rarely oxidized), MIDDLE (oxidized) and LARGE (destructed by oxidation). Tritium Inventory Tritium inventory is evaluated on an amount of tritium of the test piece accomplished of the swelling test, measured by the temperature-programmed desorption method. Specifically, the tritium inventory is evaluated on degrees of the tritium inventory as three degrees of SMALL (extremely small amount), MIDDLE (some amount) and LARGE (large amount). TABLE 3CompositionCombination ofratioProductionCrystal grainNointermetallic compounds(at %)methodsize (μm)1Be12Ti and Be17Ti28rotational30electrode2↑8HIP203↑9rotational10electrode4↑9HIP205↑10rotational20electrode6↑10HIP307Be12V and Be17V28rotational35electrode8↑9rotational25electrode9↑9HIP3510↑10rotational25electrode11Be12Mo and Be17Mo28rotational30electrode12↑9rotational20electrode13↑9HIP2514↑10rotational25electrode15Be12W and Be17W28rotational35electrode16↑9rotational25electrode17↑9HIP3518↑10rotational25electrode19Be13Zr and Be17Zr28rotational35electrode20↑9rotational20electrode21↑9HIP2522↑10rotational40electrode23Be12Nb and Be17Nb28rotational30electrode24↑9rotational20electrode25↑9HIP2526↑10rotational25electrode27Be12Ta and Be17Ta28rotational35electrode28↑9rotational25electrode29↑9HIP2530↑10rotational35electrode31Simple substance of7.7rotational35Be12Tielectrode32Be12Ti and Be5rotational50electrode33Simple substance of Be—rotational100electrodex is a ratio of M to Be TABLE 4ReactivitywithReactivityNeutronthewithThermalmultiplyingAnti-swellingstructuraltheTritiumconductivityNo.effectpropertyDuctilitymembersvaporinventory(W/m K)remarks10.89SMALL◯SMALLSMALLSMALL40presentinvention20.89↑◯↑↑↑40↑30.87↑⊚↑↑↑40↑40.87↑◯↑↑↑40↑50.85↑◯↑↑↑40↑60.85↑◯↑↑↑40↑70.89↑◯↑↑↑40↑80.87↑⊚↑↑↑40↑90.87↑◯↑↑↑40↑100.85↑◯↑↑↑40↑110.89↑◯↑↑↑50↑120.87↑⊚↑↑↑50↑130.87↑◯↑↑↑50↑140.85↑◯↑↑↑50↑150.89↑◯↑↑↑70↑160.87↑⊚↑↑↑70↑170.87↑◯↑↑↑70↑180.85↑◯↑↑↑70↑190.89↑◯↑↑↑70↑200.87↑⊚↑↑↑70↑210.87↑◯↑↑↑70↑220.85↑◯↑↑↑70↑230.89↑◯↑↑↑50↑240.87↑⊚↑↑↑50↑250.87↑◯↑↑↑50↑260.85↑◯↑↑↑50↑270.89↑◯↑↑↑60↑280.87↑⊚↑↑↑60↑290.87↑◯↑↑↑60↑300.85↑◯↑↑↑60↑310.90SMALLXSMALLSMALLSMALL40comparativeexample320.92↑◯MIDDLEMIDDLEMIDDLE55↑331.00LARGE⊚LARGELARGELARGE170conventional1) shapes after compression tests⊚: deformed (without features)◯: deformed (with micro-fractures)Δ: deformed (with small fractures)X: broken As shown in Table 4, any of the examples of the present invention is excellent in the ductility and the anti-swelling property and has a high neutron multiplying effect, a small tritium inventory and small reactivity with the structural members and the vapor. In contrast to this, the comparative example of No. 31 is poor in the ductility because this example consists of a simple substance of Be12Ti. The comparative example of No. 32 includes a metal phase as binder between beryllium intermetallic compound phases so that the ductility and the anti-swelling property are excellent, the tritium inventory is small and reactivity with the structural members and the vapor is small, however, the high neutron multiplying effect thereof is not satisfactory. The comparative example of No. 33 is excellent in the neutron multiplying effect and the ductility, because it consists of 100 vol % of metallic beryllium, but is large in the swelling and the tritium inventory and further large in the reactivity with the structural members and the vapor. In a case where the present invention is embodied with a combination of the distinct beryllium intermetallic compounds, any of the materials according to the present invention has a particularly excellent property as a material facing to plasma. Specifically, substances obtained from mixing and casting a combination of beryllium and titanium so that Be12M and Be17M2 coexist and are intermixed therein are ascertained to be remarkably improved in ductility as compared with simple substances of Be12M and Be17M2. A mixing ratio of Be12M and Be17M2 is not particularly limited, however, it is ascertained that the particularly preferable mixing ratios in a range of 10.5 to 2.0, or x in a range of 8.8 to 9.9 at % as described in a ratio x of M to Be, give especially excellent results. Moreover, concerning with metallographic structures of the composite phases of the beryllium intermetallic compounds, it is ascertained to be further advantageous in view of strength to set grain sizes of cast structures no more than 30 μm and particularly preferably no more than 20 μm. Next, production methods of the plasma facing material according to the present invention will be described hereinafter. Beryllium powder or beryllium intermetallic compound powder is prepared so as to be a desired composition and the prepared powder is filled in a mold. Stainless steel is ordinarily applied to such a mold and accomplished with canning by means of electron-beam welding. HIP is accomplished at 1200 to 1500 degree C. and 100 to 200 MPa for approximate 1 to 5 hours by means of a HIP (hot isostatic pressing) machine. Next, the material is took out of the mold and finished with machining. The plasma facing materials respectively having compositions as shown in Table 5 are produced by means of the HIP method. In this occasion, a particle size of the provided powder is 0.6 μm and the HIP condition is that the temperature is 1300 degree C. and the pressure is 150 MPa. Crystal particle sizes of the obtained plasma facing materials are in a range of 5 to 20 μm. Results of evaluation about a radiation loss, a sputtering property and a tritium absorbency of each of thus obtained plasma facing materials are described in Table 6. In addition, the respective properties are evaluated by the following procedures. Radiation Loss Smaller atomic weight gets the radiation loss more preferable, hence average atomic weight of the compounds is employed for evaluation. Sputtering Property A melting point is employed for evaluation of a physical sputtering property. Furthermore, a chemical sputtering property is on degrees of reactivity with hydrogen (at 600 degree C.) as three levels of ◯ (hardly react), Δ (slightly react) and X (considerably react). Tritium Absorbency An amount of tritium absorbed in the material after being kept in a tritium atmosphere for 3 hours is measured by the temperature-programmed desorption method and the tritium absorbency is evaluated on the measured value as three levels of LARGE, MIDDLE and SMALL. TABLE 5CompositionCombinationElementratioof intermetallicCrystal grainNoof M(at %)compoundssize (μm)1Ti6.5Be and Be12Ti152↑9.0Be12Ti and Be17Ti2103↑10.0↑84↑12.0Be17Ti2 and Be3Ti125V6.0Be and Be12V176↑9.0Be12V and Be17V2137↑10.0↑118↑12.0Be17V2 and Be3V109Mo5.5Be and Be12Mo1410↑9.0Be12Mo and Be17Mo21211↑10.0↑1012↑12.0Be17Mo2 and Be3Mo1113W6.5Be and Be12W2014↑9.0Be12W and Be17W21815↑10.0↑1616↑12.0Be17W2 and Be3W517Zr7.0Be and Be13Zr18189.0Be13Zr and Be17Zr2171910.0↑152012.0Be17Zr2 and Be3Zr1321Nb6.5Be and Be12Nb13229.0Be12Nb and Be17Nb2122310.0↑92412.0Be17Nb2 and Be3Nb1025Ta6.0Be and Be12Ta12269.0Be12Ta and Be17Ta2112710.0↑92812.0Be17Ta2 and Be3Ta1029Ti7.7Simple substance of15Be12Ti30none0Simple substance of Be5*x is a ratio of M to Be TABLE 6RadiationSputtering propertyTritiumNolossphysicalchemicalabsorbentremarks12.21500◯SMALLPresentinvention22.51520↑↑↑32.61550↑↑↑42.81500↑↑↑53.61670↑↑↑63.91700↑↑↑74.11750↑↑↑84.31650↑↑↑92.91630↑↑↑103.11650↑↑↑113.21680↑↑↑123.41600↑↑↑134.21680↑↑↑144.41700↑↑↑154.51720↑↑↑164.71650↑↑↑172.71680↑↑↑182.81700↑↑↑192.91710↑↑↑203.11650↑↑↑212.91580↑↑↑223.01600↑↑↑233.11630↑↑↑243.31520↑↑↑254.01750↑↑↑264.21760↑↑↑274.31780↑↑↑284.41700↑↑↑292.31550◯SMALLComparativeexample301.91280XLARGE↑ As shown in Table 6, any of the examples of the present invention has a small radiation loss, a small sputtering erosion and a small tritium absorbent. In contrast to this, the comparative example of No. 29 is defective of brittleness at a room temperature though satisfactory in the other properties because this example consists of a simple substance of Be12Ti. Moreover, the comparative example of No. 30 is excellent in the radiation loss, because it consists of 100% of metallic beryllium, but is poor in the sputtering property and the tritium absorbent. Although the invention has been described above by reference to certain embodiments of the invention, the invention is not limited to the embodiments described above. Modifications and variations of the embodiments described above will occur to those skilled in the art, in light of the above teachings. Moreover, throughout the present description and claims, the phrase “consisting essentially of —” is defined and used as a meaning of including — as essential ingredients but excluding additional unspecified ingredients that would affect the basic and novel characteristics of the product. However, the phrase does not exclude a possibility that the product includes any other ingredients that would not affect the basic and novel characteristic of the product. The present invention provides neutron multiplier materials for nuclear fusion reactors, which are excellent in high-temperature properties and machinability so as to be high productivity, and further easy to handle. The present invention further provides plasma facing materials for nuclear fusion reactors, which lead to small sputtering erosion and small radiation loss in a case of being contaminated in the plasma and absorb a small amount of tritium.
054992834	claims	1. An X-ray computed tomography (CT) apparatus for carrying out a helical scan imaging, comprising: input means for selecting a desired imaging region; a bed plate for supporting a body to be examined along a direction of a body axis; an X-ray source for irradiating X-rays on the body, the X-ray source and the bed plate being rotatable relative to each other at a predetermined angular speed and linearly movable relative to each other along the direction of the body axis; a detector for detecting the X-rays passing through the body; data collection means for collecting data from the detected X-rays according to the desired imaging region selected by the input means; image reconstruction means for reconstructing tomographic images according to the collected data; and control means for controlling a relative linear motion of the X-ray source and the bed plate according to the desired imaging region selected by the input means, such that the X-ray source and the bed plate are relatively linearly moved through a distance covered by the desired imaging region in a plurality of scans, each scan by the X-ray source and the bed plate including a readjustment region which overlaps a region covered by a previous scan. placing a body to be examined on a bed plate; selecting a desired imaging region; linearly moving the bed plate and an X-ray source relative to each other along a direction of the body axis of the body to be examined, while rotating the bed plate and the X-ray source relative to each other at a predetermined angular speed; detecting X-rays irradiated by the X-ray source and passing through the body to be examined by a detector; collecting data from the detected X-rays according to the desired imaging region; reconstructing tomographic images from the data collected; and automatically controlling a relative linear motion of the X-ray source and the bed plate according to the desired imaging region such that the X-ray source and the bed plate are relatively linearly moved through a distance covered by the desired imaging region in a plurality of scans, each scan by the X-ray source and the bed plate including a readjustment region which overlaps with a region covered by a previous scan. 2. The X-ray CT apparatus of claim 1, wherein the readjustment region includes a supplementary interpolation data region which is located at an end of a region covered by the previous scan and utilized in carrying out interpolations for deriving data in a part of the desired imaging region to be scanned next. 3. The X-ray CT apparatus of claim 2, wherein the supplementary interpolation data region corresponds to a 180.degree. rotation of the X-ray source around the body to be examined. 4. The X-ray CT apparatus of claim 1, wherein the readjustment region includes an initial acceleration region accounting for an initial relative acceleration of the bed plate and the X-ray source with respect to each other in a next scan. 5. The X-ray CT apparatus of claim 1, wherein the readjustment region includes a correction data region from which additional data, necessary to remove inconsistencies in the collected data introduced by a readjustment between successive scans, is collected by the data collection means. 6. The X-ray CT apparatus of claim 1, wherein the control means also controls the relative linear motion of the X-ray source and the bed plate according to the desired imaging region such that the X-ray source and the bed plate are relatively linearly moved through a distance covered by a scanning region appropriate for the data collection means to collect the data required by the image reconstruction means to reconstruct the tomographic images for the desired imaging region, the scanning region including the desired imaging region and supplementary interpolation data regions located at end portions of the desired imaging region, the supplementary interpolation data regions utilized to carry out interpolations for deriving data in the desired imaging region. 7. The X-ray CT apparatus of claim 6, wherein the scanning region also includes an initial acceleration region accounting for an initial relative acceleration of the bed plate and the X-ray source with respect to each other. 8. The X-ray CT apparatus of claim 6, wherein the scanning region also includes a final deceleration region accounting for a final relative deceleration of the bed plate and the X-ray source with respect to each other. 9. A method for helical scan imaging in X-ray computed tomography (CT), comprising the steps of: 10. The method of claim 9, wherein the readjustment region includes a supplementary interpolation data region located at an end of a region covered by a previous scan and utilized in carrying out interpolations for deriving data in a part of the desired imaging region to be scanned next. 11. The method of claim 10, wherein the supplementary interpolation data region corresponds to a 180.degree. rotation of the X-ray source around the body. 12. The method of claim 9, wherein the readjustment region includes an initial acceleration region accounting for an initial relative acceleration of the bed plate and the X-ray source with respect to each other in a next scan. 13. The method of claim 9, wherein the readjustment region includes a correction data region from which additional data, necessary to remove inconsistencies in the collected data introduced by readjustments between the successive scans, is collected by at the data collecting step. 14. The method of claim 9, wherein the controlling step also controls the relative linear motion of the X-ray source and the bed plate according to the desired imaging region such that the X-ray source and the bed plate are relatively linearly moved through a distance covered by a scanning region appropriate for the data collecting step to collect the data required by the reconstructing step to reconstruct the tomographic images for the desired imaging region, the scanning region including the desired imaging region and supplementary interpolation data regions located at end portions of the desired imaging region, the supplementary interpolation data regions utilized to carry out interpolations for deriving data in the desired imaging region. 15. The method of claim 14, wherein the scanning region also includes an initial acceleration region accounting for an initial relative acceleration of the bed plate and the X-ray source with respect to each other. 16. The method of claim 14, wherein the scanning region also includes a final deceleration region accounting for a final relative deceleration of the bed plate and the X-ray source with respect to each other.
	summary
046648682	summary	BACKGROUND OF THE INVENTION The present invention relates to a torus-type apparatus for nuclear fusion. More specifically, the invention relates to a toroidal coil apparatus in which a plurality of coils are arranged in the torus form, and particularly to such a construction for supporting an electromagnetic force. Generally, the torus-type nuclear fusion apparatus consists, as shown in FIGS. 1 and 2, of a plurality of toroidal coils 1, a vacuum container 2, air-core current transformer coils 3, and poloidal coils 4. The vacuum container 2 has a trapezoidal shape or a circular doughnut shape along the cross section therefore, and a plasma P is confined therein by a magnetic field in the toroidal direction, poloidal direction and vertical direction. The toroidal coils 1 which together surround a vertical center axis and which each surround a a common closed loop axis, have a circular shape or a D-shape to approximate the shape of the plasma P which is heated by an electric current produced by a voltage induced in the plasma P by changing the magnetic flux of the air-core current transformer coils 3 wound in the vicinity of the vacuum container 2. In a toroidal magnetic field generator of the torus-type nuclear fusion apparatus, in general, heavy currents are permitted to flow in the same direction through a plurality of coils arranged on a torus circle, thereby to generate a toroidal magnetic field. An intense electromagnetic force is generated in the toroidal coils owing to the interaction between the magnetic field and coil currents. The electromagnetic force works as an expanding force F to expand the coils in general, and is so distributed as to become intense toward the inner side of the torus and weak toward the outer side of the torus. Therefore, there develops a force (centripetal force) Fr which acts to collect the plurality of toroidal coils to the center as a whole. Further, heavy currents are permitted to flow into the poloidal coils installed adjacent to the toroidal coils to generate a poloidal magnetic field, thereby to heat the plasma, and to control the shape and the position of the plasma. Here, the poloidal magnetic field intersects the electric currents flowing through the toroidal coils, whereby a force is generated to invert the toroidal coils outwardly at the surface thereof. In the torus-type nuclear fusion apparatus, a problem remains with regard to how to support the electromagnetic force generated in the toroidal coils and how to minimize the stress generated in the toroidal coils. To cope with this problem, the conventional apparatus has been constructed as shown in FIGS. 3 to 5. That is, as shown in FIGS. 3 and 4, the toroidal coils 1, each consisting of a conductor wound in a number of turns, are contained in coil support frames 5a, 5b made of a nonmagnetic material such as SUS or a strong aluminum alloy capable of withstanding an intense electromagnetic force generated in the toroidal coils 1. The coil support frames 5a, 5b are strongly fastened at their upper and lower portions to a rack 7 by bolts 8 via coil support legs 6, so as to be capable of withstanding the weights of the toroidal coils 1, heat, electromagnetic force F, centripetal force Fr, and inverting force F.sub.Q. Further, wedge-like coupling portions 5c are provided to support the centripetal force Fr at positions of wedge portions 1a at the inner end portions of toroidal coils 1. The toroidal coils 1 contained in the coil support frames 5a, 5b are arranged in a plurality of coils in a toroidal direction. Then, a force is applied to the back side of the coils using hydraulic jacks or the like with the coil support frames 5b being located on the center side, in order to collect the toroidal coils 1 in a precise radial form. Then, the coil support legs 6 are fastened and secured to the rack 7 by bolts 8 so that the wedge surfaces of the wedge-like coupling portions 5c provided on the inner side of the coil support frames 5a, 5b are intimately contacted with each other, and that the centripetal force Fr is correctly received via the wedge surfaces. Further, the inverting force F.sub.Q illustrated in FIG. 6 is received by inversion preventing beams 9a, 9b which are provided between the coil support frames 5a and 5b as shown in FIG. 5. In recent years, however, an increase in the scale of the apparatus has resulted in an increased intensity of the magnetic field and increased electromagnetic forces, making it difficult to support the centripetal force Fr and the inverting force F.sub.Q. That is, efforts have been made to maintain the wedge effect against the centripetal force Fr by relying upon the wedge surfaces of the wedge-like coupling portions 5c. However, as the coils are constructed in larger sizes and the total height of the coils becomes large, it becomes difficult to maintain precision while constructing the coils. Therefore, despite the fact that the coils are pushed by hydraulic jacks and are secured by bolts 8, the pushing force Ft for the coils is effective only in the vicinities of coil support legs 6; i.e., it is no longer possible to maintain the pushing force Ft for the total height of the coils. In order to reduce the inverting force F.sub.Q, furthermore, inversion preventing beams 9a, 9b are provided but avoiding the plasma observation ports 10. Therefore, the inverting force F.sub.Q is not supported by the whole surfaces of coils. Further, the distance l increased between the wedge-like coupling portions 5c and the inversion preventing beams 9a, and increased stress is exerted on the straight portions of the coils. Moreover, wedge surfaces of the wedge-like coupling portions 5c are not capable of supporting the pushing force Ft, and hence exhibit rigidity no more against the inverting force F.sub.Q. Furthermore, even if it is attempted to install inversion preventing beams near the wedge surfaces, only very thin inversion preventing beams are allowed to be installed as a result of an increased number of toroidal coils in the apparatuses constructed in recent years. Namely, this arrangement does not permit structure to be employed very thin inversion preventing beams to the coil support frames 5a by coils. It is therefore difficult to reduce stress exerted on the straight portions of the coils. SUMMARY OF THE INVENTION The present invention was accomplished in view of the above-mentioned defects, and has for its object to provide a toroidal coil apparatus which is capable of reducing stress due to the inverting force.
047059516	description	DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings wherein reference numerals are used to designate parts throughout the various figures thereof, there is shown in FIG. 1 a front view in partial section of a wafer processing system according to the invention. An input load-lock 10 is used to load a cassette of wafers. An isolation valve 12 is located in the path of the wafer before the first processing chamber 14. A second isolation valve 16 is located in the path of the wafer before the second processing chamber 18. A third isolation valve 20 is located between the second processing chamber 18 and the output loadlock 22. A computer 24 with controls through a keyboard and touch-screen is used to control operation of the system. Separate vacuum pumping connections 26, 28, 30, 32, 34, 36 and 38 are made to each of the loadlocks 10, 22, valves 12, 16, 20 and processing chambers 14, 18. Each pumping connection is controlled from the computer 24. Only two processing stations are shown in this example, but any number of processing stations and isolation valves can be used in series. FIG. 2 shows a partial section through the line 2--2 of the system of FIG. 1 and FIG. 3 shows a partial section of the same system through the line 3--3. In FIG. 2, wafer handling arms 40, 42, 44 are shown in solid lines in the stored position. Wafer handling arm 40 is shown in dotted lines 46 taking a wafer 48 from a cassette 50. Wafer handling arm 40 is shown in dotted lines 52 placing the wafer 48 in the processing chamber 14. Similarly, wafer handling arm 42 is shown in dotted lines 54 as it picks up the wafer in the first processing chamber 14 and in dotted lines 56 as it places the wafer in the second processing chamber 18. Wafer handling arm 44 is shown in dotted lines 58 taking a wafer from the second processing chamber 18 and in dotted lines 60 placing the wafer in the output cassette 62. In FIG. 3, the wafer handling arms 40, 44 are shown in the stored position inside valves 12, 20 with the valve wedge 64, 66 seated in the closed position. The wafer handling arm in the valve 16 is shown in solid lines 68 in the first processing chamber 14 and in dotted lines 56 in the second processing chamber 18. The valve wedge 69 of the valve 16 is shown in the open position, showing that the handling arm can move through the opening 71 in the valve seat in either direction. Further details of an individual of the valves and wafer handling arms as previously described are shown in FIGS. 4-9. The device is shown in FIG. 4 in side view. A plate 70 with sealing O-ring 72 is used to seal the valve and wafer, handling arm into the system. As shown in FIG. 3, the plate 70 is positioned in abutment with the main frame of the system. FIGS. 4-6 show that the valve wedge 74 and its operating mechanism, and the wafer handling arm 84 and its operating mechanism, are all attached to plate 70 to form a unitary structure. FIG. 8 shows that plate 70 is provided with slots 71 and an aperture 73 to receive bolts (not shown) for attaching the valve and wafer arm unit to the main frame of the system. This construction makes it possible to remove and replace the valve and wafer arm quickly as a single unit, and without dismantling any other portion of the system. The valve wedge 74 has O-rings 76, 78 on either side to seal to the valve seat 80 (shown in FIG. 3). A linear actuator 82, which may be pneumatically, hydraulically or electrically driven, is used to drive the valve wedge 74 upward into the seat 80. This upward movement is shown in FIG. 5 with the valve wedge 74 shown in dotted lines in the uppermost closed position. The wafer handling arm 84 remains at the same height in the system regardless of whether the valve wedge 74 is in the uppermost closed position or the lowermost open position. The valve wedge 74 has a storage notch 88 to allow the valve wedge 74 to pass around and seal the arm 84 within the valve. The wafer handling arm 84 is provided with two rotary actuators 90, 92 which drive concentric shafts 94, 96 through toothed belts 98, 100 and toothed pulleys 102, 104, 105, 106. The concentric shafts 94, 96 are mounted in a shaft holder 107 and supported at the top and bottom with roller bearings 108, 110, 112. In order to provide good rotating vacuum seal to the shafts, two pairs of O-rings 114, 116, 118, 120 are provided around each shaft. A hole 122 is provided through the outer shaft 96 which is in communication with a groove 124 on the inner shaft 94. A groove 126 on the outer shaft 96 communicates with the hole 122 and a pumping outlet 128 in order to provide other vacuum pumping or pressurization between each pair of O-ring seals on each shaft. A bellows seal 130 is provided between the valve wedge 74 and the plate 70. The handling arm 84 is made of four smaller pieces. A proximal support piece 132 is fixedly attached at a right angle at a first end to the outer shaft 96. A distal support piece 134 is pivotally attached at one end to the other end of the proximal support piece 132. A proximal extensor piece 136 is fixedly attached at a right angle at a first end to the inner shaft 94. A distal extensor piece 138 is pivotally attached at one end at the second end of the proximal extensor piece 136. The distal extensor piece 138 is pivotally attached at the second end of the distal support piece 134. The attachment points on the distal support piece 134 to the proximal support piece 132 and distal extensor piece 138 are separated by the dimension on the proximal extensor piece 136 between the attachment points. The proximal extensor piece 136 can be much shorter than the proximal support piece 132. The smaller the proximal extensor piece 136 relative to the proximal support piece, the smaller the arm can be when in the folded position. The four pieces of the arm should form a pareallelogram between the attachment points and the shaft axis. If all four arm pieces are formed as blades, the pivotal attachments can be loosely fixed rivets. As the outer shaft 96 is rotated the entire arm rotates. As the inner shaft 94 is rotated relative to the outer shaft, the arm extends or folds. The arm thus described can be moved such that the tip holding the wafer moves in any complex trajectory by independently rotating the concentric shafts. The small space required to store the arm permits the arm to be stored within an isolation valve housing. The housing of the valve can be formed as a separate unit or as an integral part of the process chambers as shown previously. Mounting the driving means for the arm and make as shown previously permits the moving parts to be removed and replaced as a unit quickly, thus minimizing downtime. The valve may be pumped by the same pumping system as is used for the process chamber, either simultaneously or by time-sharing the pumping mechanism through alternating valves. If simultaneous pumping is necessary, the chemically active process gas being pumped out of the process chamber will backstream into the valve housing. This can be prevented by maintaining a small flow of an inert gas into the valve housing to continuously flush the housing and pump line. This flow can be as little as 5 cc/min. In FIGS. 1 and 10, the loadlock and elevator mechanism according to the invention is shown. The loadlock door 150 has attached to it a pair of rods 152 which ride on bearings 154 mounted to the outside of the loadlock chamber 156. The cassette 62 rides on a table 158 which is keyed to sit the cassette 62 in only one position. A microswitch 160 or other equivalent sensor is used to detect the cassette 62 when it is seated properly. The computer which controls the system is programmed to hold the loadlock door 150 open until the cassette 62 is properly seated. The table 158 rides on a shaft 162 which terminates in a bar 164. The bar 164 is driven by a screw 166 from a motor 168 and pulley 170. A guide rod 172 and bearing 174 is used to steady the elevator. A bellows 176 seals the chamber 156 to the bar 164 to provide vacuum sealing around the shaft 162. As shown in FIGS. 1, 10 and 11, there is an O-ring 178 located on the back of the door 150 which seals to the surface of the chamber 156 when the door is pushed closed. The main locking mechanism of the loadlock is the pressure of the atmosphere on the door 150 when the chamber 156 is evacuated through the pumping port 180. To aid in compressing the O-ring 178 and in holding the door 150 until the pressure in the chamber 156 drops enough to hold the door 150 closed, a vacuum or soft soft latch is provided. The soft latch is comprised of as many as four O-ring seals 182, preferably of neoprene foam, mounted in the walls of the chamber 156 outside the O-ring 178 as shown in FIG. 11. These O-ring seals may be configured in a shape and size adequate to provide sufficient force to hold the door in intimate contact with the O-ring 178. The neoprene foam O-ring can be of the open-celled or closed-cell types, but a soft closed-cell neoprene O-ring works particularly well. FIG. 11 is a view of the rear of the door as an example, with the position to which the O-ring seals 182 mate shown in phantom (since the seals 182 are on the face of the chamber). The O-ring seals 182 can be on the door, but it is more convenient to run the pumping channels through the chamber. Each seal 182 seals to a smooth surface on the back of the door 150 if the seals are on the chamber as illustrated. If the seals are on the door, the smooth surface is on the chamber. At the center of each seal 182 a hole 184 leads through a channel 186 to a valve and pumping system as shown in FIG. 12. A microswitch detector 188 detects the closing of the door 150. The valve to atmosphere 188 is closed and the valve to the pumping system 190 is opened in sequence. The vacuum drawn under the seals 182 then hold the door 150 closed. If it is necessary to open the chamber 156 by hand before evacuating the chamber, a switch 192 on the handle 194 is used to close the valve 190 to the pumping system and open the valve 188 to the atmosphere in sequence. The seals 182 then release the door. Once the pumping on the chamber 156 has begun, the soft latches are automatically released by the computer 24. Thus, it is advantageous to locate the soft latch outside the main O-ring seal 178. This system of soft latching is particularly advantageous for automatic handling of the cassettes. Depending on the size of the door and the closeness of fit of the mounting system, two to four or more soft latches may be necessary. For a small door with a well-fitted hinge, a single soft latch of sufficient size will be adequate. In FIG. 13 there is shown an embodiment where a door 196, mounted on a hinge 197 and having only one sealing O-ring 198, has a single seal 198 mounted on the chamber to act as a soft latch. The position where the soft latch contacts the door is shown in phantom. Because cassettes become worn or otherwise deformed, the position of a wafer relative to the elevator mechanism cannot be determined from a known geometry of a cassette. Also, wafers might be broken or discarded in previous processing steps and thus missing from cassette slots. In order to compensate for these problems there is included in the chamber an optical or infrared transmitter 200 and a matching optical or infrared detector 202 on the opposite side of the chamber 156 at the same height. As the chamber 156 is being evacuated, the elevator table 158 is driven up and then down. As each wafer passed through the beam from the transmitter 200, the interruption of the beam is sensed at the detector 202. The interruptions are recorded in the control computer 24 and associated hardware. The elevator is driven at a constant known speed so that position is known from the product of speed and time. Position is measured relative to the elevator table 158. Thus, position of each slot of the cassette and presence of each wafer is known. The control computer 24 is then programmed to pick up each wafer at the measured position in the computer memory and to skip cassette spaces where there is no wafer. The combination of wafer handling mechanism described before and wafer positioning system permits the system to be operated with random access to the wafers in the input cassette and random selection of cassette spaces to store the outgoing wafer. In FIGS. 14-16 there is shown the device for receiving, centering and holding the wafer during processing according to the invention. The wafer is centered over the chuck platform 210 using the wafer handling arm. Lifting pins 212, in combinations of 3 or more, are raised under the wafer to lift the wafer off the handling arm. The handling arm is then withdrawn from the chamber. The wafer is then left on the lifting pins 212 with the pins in the extended position as shown in dotted lines in FIG. 15 and solid lines in FIG. 16. At the same time the lifting pins 212 are extended upward, the holding pins 214 are extended upward at a slant away from the wafer. Each holding pin 214 has a head enlargement 216 which is larger in diameter than the shaft of the holding pin. The head enlargement 216 may be formed as a small disk, cylinder or other object. The head enlargement 216 must be sufficiently large and abrupt to catch the edge of the wafer. As the lifting pins 212 are drawn downward by the springs 213 to place the wafer on the top of the chuck platform 210, the holding pins 214 clamp the edge of the wafer with the heads 216. There may be two or more holding pins 214, but the more holding pins 214 the more firmly the wafer is held to the chuck. A capacitative sensor 218 is used to confirm the seating of a wafer on the chuck. Each holding pin 214 is fixed to a pin holder 220 which forms a guide for the pin. Each pin holder 220 is driven downward by a spring 222. The lifting pins 212 and the holding pins 214 are driven in common by a lifting table 224. The lifting table 224 has a rounded upper rim and the pin holder 220 has a rounded lower end to facilitate a smooth sliding motion of the pin holder 220 on the lifting table 224. The lifting table 224 is driven upward on a threaded shaft 226 and threaded cylinder 228. A bellows and O-ring seal 230 around the threaded cylinder 228 is used as a vacuum seal. The threaded shaft 226 is driven by a pulley 232 and motor 234. A wafer clamped firmly to a chuck platform 210 as previously described can be heated or cooled from the backside by gas fed from the interior of the chuck, the gas being used as a heat transfer medium between the chuck and the wafer. Within the chuck platform 210, a plenum 236 is fed gas through an internal channel (not shown) from a source outside the vacuum. Radial channels 238 are used to feed the gas into a series of radial, concentric or combination (of radial and concentric) grooves on the surface of the chuck (not shown). Leakage of gas from under the wafer necessitates a continuous flow of gas. The temperature of the chuck is monitored with sensors and thereby regulated. Another chuck is shown in FIGS. 17 and 18. In some applications where it is preferable to use helium gas it is necessary to provide clamping means to seal the wafer more firmly to the surface of the chuck. In this chuck, the wafer 300 is shown on the chuck surface 302. Three or more lifting pins 304 lift the wafer 300 off the handling arm as shown in phantom in FIG. 17 and lower the wafer 300 to the surface 302. The pins 304 are attached to a spider 306 and driven by a pneumatic actuator 308. Bellows 310 provide vacuum seals around the pins. Temperature control gas is introduced at the inlet 312 and passes through an interior channel 314 to a central well 316 in the surface 302 of the chuck. Channels 318 are provided for fluid for temperature regulation around the interior of the chuck. Radial slots 320 are provided on the surface 302 on the chuck connected to the well 316. Slot stops 322 block the slot and force the helium under the wafer. To hold the wafer firmly to the chuck a multiplicity of clamps are provided. From 3 to about 72 clamps can be used on a six-inch wafer. For smaller wafers, fewer can be used, and for larger wafers, more can be used. Eight are shown here for simplicity. Each clamp comprises a thin hook 324 of sheet metal connected to a spring 326 arranged around the outside of the wafer. There is a spreading ring 328 provided with a slot 330 through which each hook 324 passes. The slot 330 is optional as the hooks sit on the lifting ring 332 without the slots. There is a lifting ring 332 below the spreading ring 328. The spreading ring is provided with two or more pneumatic actuators 334 (three are shown here) and bellows vacuum seal 336. The lifting ring 332 is likewise provided with two or more pneumatic actuators 338 (three are shown here) and bellows vacuum seal 340. Each hook 324 has an upper holding lip 342, lower spreading lip 344 and lifting slot 346. In a motion with the hooks going from the upper and spread position to a down and clamped position, the spring 326 forces the hook 324 to pivot around the lifting ring 332 at the lifting slot 340 and push against the edge of the wafer 300, thus, centering the wafer amongst the hooks. In a motion with the hooks going from the down and clamped position to an upper and spread position, the lifting ring 332 is lifted toward the wafer, the hook 324 is forced upward releasing the pressure on the top of the wafer at the holding lip 342. As the spreading ring 328 is lowered to pressure the hook 324 at the spreading lip 344, the hook 324 pivots outward around the lifting slot 346. The holding lip 342 then swings clear of the wafer 300 and the lifting pins 304 can be used to lift the wafer to the handling arm. A capacitance sensor 348 and/or an optical sensor 350 and/or a backside pressure sensor (not shown) can be used to sense the presence of the wafer 300. This information is sent to the system computer 24. The main body of the chuck 352 can be removed to service the sensors 348 or 350 by removing the bolts 354 while leaving the clamping mechanism in place. For either embodiment of the wafer holding chuck, the chuck may be heated with cartridge heaters and cooled with a fluid such as water. Alternately, the fluid may be heated and cooled externally. The temperature of the chuck can be monitored with sensors and the temperature can be regulated with the aid of a control computer which may be combined with the processing computer 24. In FIG. 19, the task locator system is diagrammed. Here a system of two process chambers, three valves with wafer handlers and two loadlocks are used in this example. Any number of process chambers could be used with corresponding valves and wafer handlers. At the top left of this diagram various task symbols are defined. For example, SND means vent or pump down the sender loadlock. Various task status symbols are defined at the right of the diagram. Status #1 means the element is not ready or waiting to do anything. Status #2 means the element is ready to operate with a wafer present to be operated upon. Status #3 means the element is active. This code is not used in the matrix of the diagram in FIG. 19, but is defined for the sake of completeness. Only the absence of activity is needed for a given task to operate. Status #4 means the element can be in status 1 or 2, but not 3. The fifth status symbol "any" means element can be in any of the other four status conditions. There is a difference between states of the tasks which can be only 1, 2 or 3 and the required state which can be also 1, 2 or the combinations 4 and 5. Most tasks proceed from 1 to 2 to 3 and back to 1, except SND which proceeds from 1 to 2 to 3 and back to 2. A few examples will be given here to help understand the meaning of these status categories. When there is no wafer in a process chamber, the status of C1P, for example, is #1. After the wafer is moved into the chamber, the status changes to #2. Then the process begins and the status is changed to #3. When the process is finished the status changes back to #1. The valves will proceed through the same sequence of changes of status, but presence of a wafer is detected in the upstream compartment rather than in the valve itself. The only time there is a wafer in the valve itself is when the valve is active. The task locator system senses the actual status of each element of the system and stores that status in the computer according to the three categories of status named above. Each element is instructed to act independently of the actions of each other element if the status conditions of the other elements are correct. The system does not operate according to a fixed timed sequence. The task locator continuously compares actual status of the tasks labelled on the left of the matrix with each of the columns showing required status in the table diagrammed in FIG. 19 to determine if any task may be started. If the conditions are as shown in the table, it then starts those tasks and updates the status for the next time. In this way, an optimum sequence will evolve regardless of the relative durations of each of the tasks. This is because the task locator does not attempt to define a sequence, but rather pursues the more abstract goal of keeping the system as busy as possible at all times. For example, in order to determine under what conditions the receiver valve between the second process chamber and the receiver loadlock will operate, read across the row of task names at the top to WRM, the second column from the end. Then read down to each status symbol and across to the left for the task name. The system doesn't care what the sender loadlock is doing, nor the first valve, nor whether the first process chamber is active or not. It does demand that valve #2 between the chambers be inactive (W2M=4), that the process in the second process chamber be completed (C2P=1), that the receiver valve is ready to operate with a wafer present in the second process chamber (WRM=2), and the receiver loadlock be empty (RCV=1). Under these conditions the receiver valve will operate regardless of sequence. This invention is not limited to the preferred embodiments and alternatives heretofore described, to which variations and improvements may be made including mechanically and electrically equivalent modifications, changes and adaptations to component parts, without departing from the scope of production of the present patent and true spirt of the invention, the characteristics of which are summarized in the appended claims.
06294858&	claims	1. A microminiature thermionic converter comprising: a first substrate comprising a dielectric material; a second substrate comprising material selected from the group consisting of dielectric material and semiconductor material, the second substrate having a recess therein including at least one wall and a floor boundary, and the second substrate being positioned adjacent to the first substrate so that the recess opposes the first substrate: 2. The microminiature thermionic converter of claim 1 wherein the first coating has a first work function and is selected from the group consisting of BaO, SrO, CaO, Sc.sub.2 O.sub.3 and a mixture of BaSrCaO, Sc.sub.2 O.sub.3 and metal, and any combinations thereof, and the second coating is different from the first coating and has a second work function different from the first work function. 3. The microminiature thermionic converter of claim 2 wherein the second coating is selected from the group consisting of BaO, SrO, CaO, Sc.sub.2 O.sub.3, and a mixture of BaSrCaO, Sc.sub.2 O.sub.3 and metal, and any combinations thereof. 4. The microminiature thermionic converter of claim 3 wherein the first conductor and the second conductor are electrically connected via a device consuming electrical power.
	abstract	Systems for x-ray microscopy using an array of micro-beams having a micro- or nano-scale beam intensity profile to provide selective illumination of micro- or nano-scale regions of an object. An array detector is positioned such that each pixel of the detector only detects x-rays corresponding to a single micro-or nano-beam. This allows the signal arising from each x-ray detector pixel to be identified with the specific, limited micro- or nano-scale region illuminated, allowing sampled transmission image of the object at a micro- or nano-scale to be generated while using a detector with pixels having a larger size and scale. Detectors with higher quantum efficiency may therefore be used, since the lateral resolution is provided solely by the dimensions of the micro- or nano-beams. The micro- or nano-scale beams may be generated using a arrayed x-ray source and a set of Talbot interference fringes.
	abstract	Disclosed herein is a multi-particle beam column including electrode layer with eccentric apertures. The multi-particle beam column includes two or more particle beam columns each comprising a particle beam emission source, a deflector, and two or more electrode layers. The multi-particle beam column includes at least one electrode layer having one or more apertures that are eccentric from respective beam optical axes of the particle beam columns.
052251497	summary	BACKGROUND OF THE INVENTION The present invention relates to nuclear power reactors, and more particularly to a method and apparatus for detecting thermal hydraulic oscillations in the core of a boiling water reactor. By the nature of its design, a boiling water reactor (BWR) operates at or near the nucleate boiling point of the coolant which flows through the reactor core. During certain startup conditions, before the main coolant pumps are started, but while operating in the power range under natural circulation flow, voids (steam) can appear within the active fuel region of the core. These local voids are less dense than the surrounding coolant and this results in a decrease in the local moderation of neutrons. The decrease in moderation and thermalization of neutrons, results in a decrease in the nuclear fission rate in the nearby fuel. Such localized depression of the thermal neutron flux can, under certain conditions, cause a power unbalance and thermal-hydraulic instability in the reactor. These can rapidly progress to large thermal hydraulic oscillations. Boiling water nuclear reactors typically contain a variety of instrumentation, including a plurality of local power range monitors (LPRM) distributed throughout the core. The LPRM is typically responsive to thermal-neutron flux and thus responds to localized flux depressions resulting from localized voiding. One known approach for detecting thermal hydraulic oscillations, uses the LPRMs and monitors the peak-to-peak level between selected quadrant symmetric LPRMs. When the peak-to-peak flux levels exceed a predetermined limit, an alarm or automatic corrective action is initiated. This prior art technique relies on stochastic signal noise analysis. Because noise analysis is computationally time-consuming, this conventional technique provides a relatively late indication of the occurrence of a problem. In other words, the oscillation is well underway before the detection system of the prior art generates an alarm or initiates corrective action. SUMMARY OF THE INVENTION It is an object of the present invention to provide a method and apparatus for detecting the occurrence of thermal hydraulic oscillations in a nuclear reactor core, by overcoming deficiencies in current techniques that rely solely on neutron flux monitoring. More particularly, it is an object of the present invention to monitor parameters indicative of core thermal hydraulic behavior, with sufficient speed and sensitivity to detect incipient core thermal hydraulic oscillations. It is a further object of the invention to provide a method and apparatus by which improvement can be made to the performance of neutron-flux sensitive thermal hydraulic oscillation detection systems, without the need to replace or modify the fuel assemblies or core support structure in the reactor. These objects are accomplished with the present invention by exploiting the difference in the effect of an increase or a decrease in localized voiding, on the local thermal neutron flux and the local gamma radiation flux. Whereas thermal neutron flux is significantly affected by local voiding, the gamma flux is not significantly affected. More generally, a first type of sensor is provided which is representative of localized power generation in the core (and is significantly affected by localized coolant density, i.e., voiding) and correlated to a second type of sensor which is representative of the power in a region of the core (and does not vary significantly with localized density, or voiding). The approach of the present invention is to not only sense the local void condition, but also to sense the collapse of the local void. The void dynamics are measured and correlated regionally, compared with an acceptance reference criteria, and an alarm or other output is generated to indicate that the core is approaching an unstable condition. In a preferred form of the invention, a plurality of neutron flux sensors and a corresponding plurality of gamma flux sensors are distributed regionally at the same or closely proximate locations. A steady state comparison, or bias, between the signals of a given neutron/gamma sensor pair are monitored, and a divergence (or convergence) can readily be detected through simple signal filtering, to detect a shift in the bias. The pattern of significant convergence and divergence throughout the core, is indicative of the thermal hydraulic stability of the core. An instable pattern can be recognized, in one embodiment, by assigning to each neutron/gamma sensor pair, a coded value of, for example, plus 1, 0, or minus 1, representing void collapse, stable and void increase conditions, respectively. The assignment of a code is based on a given phase shift between the two signals. A straight forward information code calculation such as a gray code can then be made symbolic of the oscillation precursor pattern. The number of plus 1's versus the number of minus 1's, are the operatives and need not be quadrant related to point to a high probability of instability. Thus, the method of the present invention comprises the steps of sensing at each of a plurality of locations within the core, changes in the local neutron flux and gamma flux. From the sensed changes, output data indicative of the spatial distribution and time dependence of voids in the core, are generated. A system embodiment of the present invention, comprises a plurality of a first type of sensor spatially distributed in the core and sensitive to localized power fluctuations. A plurality of a second type of sensor is spatially distributed in the core, and relatively insensitive to localized power fluctuations. First means are provided for associating each of the first type of sensor with one of the second type of sensor, to define a plurality of paired measurement values. Second means are provided for generating first output data signals commensurate with a quantitative relationship among the paired measurement values. Third means, responsive to the second means, are provided for generating second output data indicative of the spatial distribution of voids in the core. The present invention is an improvement over known techniques for detecting void induced-thermal hydraulic oscillations, because a stochastic process analysis need not be developed through Fourier or other techniques. This avoids the need for large amounts of sampled data to develop statistical validity. The limitation in the inventive system is the time response of the sensors. The detection of incipient stability can be achieved in less than about five seconds. These and other objects and advantages of the invention may be better understood from the following description of the preferred embodiment.
039490270	claims	1. A process for the compaction of a ceramic nuclear fuel pellet in a compaction chamber comprising an upper fixed punch and a lower movable punch surrounded by a stationary vertically extending lateral wall by compressing the pellet therein, wherein compression is effected by shifting the movable punch towards the fixed punch, and wherein the lateral wall is inclined outwardly toward the direction of the fixed punch for at least a part of the distance between the fixed and movable punches wherein the angle between the inclined wall and an imaginary line where a noninclined wall would have been is between 1.degree.30' and 0.degree.6'. 2. The process of claim 1 wherein the lateral wall is inclined over the entire distance between the fixed punch and the movable punch. 3. The process of claim 1 wherein the lateral wall is inclined only over that portion of the distance between the fixed and movable punches from the fixed punch to a point distant therefrom corresponding to the height of the pellet after compression.
	claims	1. A device for sealing a tube in an opening located in a component, comprising: a hydraulically driven pressure element being in operative connection with the tube for pressing the tube against the component, said pressure element producing a contact pressure power between the tube and the component, and said contact pressure power containing a hydraulic power factor, said pressure element having a pressure part producing a force and a disk spring producing a preloading force, said disk spring disposed between said pressure part and the component. 2. The device according to claim 1 , including: claim 1 a hydraulic line connected to said hydraulically driven pressure element; and a pressure gauge connected to said hydraulic line for measuring the preloading force of said disk spring. 3. A device for sealing a lance shaft in a nozzle connected to a cover of a reactor pressure vessel, comprising: a hydraulically driven pressure element being in operative connection with the lance shaft for pressing the lance shaft against the cover of the reactor pressure vessel, said pressure element producing a contact pressure power between the lance shaft and the cover of the reactor pressure vessel, and said contact pressure power containing a hydraulic power factor, said pressure element having a pressure part producing a force and a disk spring producing a preloading force, said disk spring disposed between said pressure part and the cover of the reactor pressure vessel. 4. The device according to claim 3 , including: claim 3 a hydraulic line connected to said hydraulically driven pressure element; and a pressure gauge connected to said hydraulic line for measuring the preloading force of said disk spring.
	description	This is a continuation application of U.S. patent application Ser. No. 13/388,500, filed on Mar. 2, 2012, now U.S. Pat. No. 9,230,694, issued Jan. 5, 2016, which is a national stage application of PCT Application No. PCT/JP2010/062178 filed on Jul. 20, 2010, which claims priority to Japanese Patent Application No. 2009-183670 filed on Aug. 6, 2009, the entire contents of each of which are incorporated by reference herein in their entirety. The present invention relates to a method of determining nuclear fusion irradiation coordinates and a device for determining nuclear fusion irradiation coordinates by which irradiation coordinates of energy lines onto nuclear fusion fuel are determined, and a nuclear fusion device using the method and device. Nuclear fusion is expected to become a future energy source as an alternative to fossil fuel, etc. In particular, in the field of laser fusion that is a system of inertial confinement fusion, since a fast ignition system using peta watt (PW) laser light with ultrahigh power was proposed in the early 1990s, it has been energetically developed by various research institutes, and the fundamental study thereof is being rapidly developed. In laser fusion using direct irradiation represented by a fast ignition system and a central ignition system, by irradiating laser light onto a nuclear fusion target (pellet), fuel is compressed (imploded) to the central portion of the target, and an ultrahigh-density state is created. At this time, for stably causing inertial confinement fusion, high-density compression of fuel is essential, and for this, the nuclear fusion target must be irradiated and compressed as uniformly as possible. For example, a conventional configuration for obtaining uniform irradiation of laser light, a nuclear fusion device in which irradiation coordinates of 60 laser lights are set to be spherically symmetrical is known (refer to Non-Patent Literature 1 listed below). [Non-Patent Literature 1] “Laboratory for Laser Energetics, OMEGA 60,” [online], updated in June 2009, [searched for on Jul. 23, 2009], on the Internet <URL: http://www.lle.rochester.edu/05_omegalaserfacility/05_omegalaserfacility.php> However, in the above-described device, uniformity of laser light irradiation is still insufficient for causing inertial confinement fusion. Therefore, the present invention was made in view of this problem, and an object thereof is to provide a method of determining nuclear fusion irradiation coordinates, a device for determining nuclear fusion irradiation coordinates, and a nuclear fusion device that efficiently improves the uniformity of energy lines to be irradiated. In order to solve the above-described problem, a method of determining nuclear fusion irradiation coordinates according to the present invention is a method of calculating irradiation coordinates of energy lines when the energy lines are irradiated onto nuclear fusion fuel, comprising: an initial arrangement step of virtually arranging a predetermined number of electric charges on a predetermined number of initial coordinates on a spherical surface set by using random numbers; a coordinate analysis step of analyzing coordinates of the predetermined number of electric charges arranged at initial coordinates in time series by an information processing device based on coulomb forces acting among the predetermined number of electric charges by constraining the coordinates onto the spherical surface; a potential evaluation step of determining a timing at which potential energies of the predetermined number of electric charges were stabilized based on the coordinates analyzed in the coordinate analysis step; and an irradiation coordinate deriving step of deriving coordinates of the predetermined number of electric charges at the timing determined by the potential evaluation step as irradiation coordinates of energy lines in a case where nuclear fusion fuel is arranged at the center of the spherical surface. Alternatively, a device for determining nuclear fusion irradiation coordinates according to the present invention is an information processing device that calculates irradiation coordinates of energy lines when the energy lines are irradiated onto nuclear fusion fuel, comprising: an initial arrangement means for virtually arranging a predetermined number of electric charges at a predetermined number of initial coordinates on a spherical surface set by using random numbers; a coordinate analysis means for analyzing the coordinates of the predetermined number of electric charges arranged at the initial coordinates in time series based on coulomb forces acting among the predetermined number of electric charges by constraining the coordinates onto the spherical surface; a potential evaluation means for determining a timing at which potential energies of the predetermined number of electric charges were stabilized based on the coordinates analyzed by the coordinate analysis means, and an irradiation coordinate deriving means for deriving coordinates of the predetermined number of electric charges at the timing determined by the potential evaluation means as irradiation coordinates of energy lines in a case where nuclear fusion fuel is arranged at the center of the spherical surface. With such a method of determining nuclear fusion irradiation coordinates and a device for determining nuclear fusion irradiation coordinates, electric charges are virtually arranged at a predetermined number of initial coordinates on a spherical surface by an information processing device, the coordinates of the electric charges are analyzed in time series, and based on coordinates at a timing at which potential energies of the electric charges were stabilized, irradiation coordinates of energy lines when nuclear fusion fuel is arranged at the central portion of the spherical surface are derived. Accordingly, with a smaller number of coordinates of energy lines as compared with the conventional case, uniformity in irradiation intensity of energy lines on the nuclear fusion fuel is improved. Further, a nuclear fusion device according to the present invention is manufactured by using the above-described method of determining nuclear fusion irradiation coordinates, and includes a nuclear fusion target for igniting a nuclear fusion reaction by irradiating energy lines, and a predetermined number of energy line sources provided at positions corresponding to irradiation coordinates calculated by the method of determining nuclear fusion irradiation coordinates when the nuclear fusion target is arranged at the center of a spherical surface. With this nuclear fusion device, uniformity in irradiation intensity of energy lines onto nuclear fusion fuel is improved, so that inertial confinement fusion can be stably caused. According to the present invention, uniformity of energy lines to be irradiated can be efficiently improved. Hereinafter, a preferred embodiment of a method of determining nuclear fusion irradiation coordinates and a device for determining nuclear fusion irradiation coordinates according to the present invention will be described in detail with reference to the drawings. In the description of the drawings, portions identical to or equivalent to each other are designated by the same reference signs, and overlapping description will be omitted. First, a principle of inertial confinement fusion in a nuclear fusion device to which a method of determining nuclear fusion irradiation coordinates is applied is described with reference to FIGS. 8A and 8B. FIG. 8A is a view showing a principle of a central ignition system as a system of inertial confinement fusion, and FIG. 8B is a view showing a principle of a fast ignition system as another system of inertial confinement fusion. In the central ignition system, as shown in FIG. 8A, as a nuclear fusion target (pellet) for igniting a nuclear fusion reaction, a spherical target 901 consisting of a DT fuel layer 902 and an ablator layer 903 is used. By irradiating laser light 904 onto this target 901, the spherical fuel layer 902 is compressed spherically symmetrically. Then, by compressing comparatively low-density and high-temperature plasmas formed in the central portion by peripheral low-temperature and high-density plasmas at a final stage, a hot spot for ignition of a nuclear fusion reaction is produced at the central portion. In the fast ignition system, as shown in FIG. 8B, a target 911 consisting of a DT fuel layer 912, an ablator layer 913, and a cone 914 is used. In this system, the fuel layer 912 is compressed to the central portion by irradiating laser light 915B onto the fuel portion of the target 911. Further, by irradiating peta watt laser light 915A from the cone 914 side, high-energy electrons are produced at the tip end portion of the cone 914. The high-energy electrons are transmitted and transported through the cone 914 made of a metal thin film of gold, etc., and finally heats the fuel compressed to a high density, and accordingly, a hot spot for ignition of a nuclear fusion reaction is produced. For realizing these ignition systems, a high compression density of fuel is required, and as a result, high implosion uniformity and laser light irradiation uniformity are demanded. The method of determining nuclear fusion irradiation coordinates and the device for determining nuclear fusion irradiation coordinates according to the present invention are for designing irradiation coordinates of energy lines in a nuclear fusion device to meet the described demand. Here, as energy lines to be irradiated for nuclear fusion ignition, laser light is used, and a D (deuterium)-T (tritiated hydrogen) reaction is assumed as a nuclear fusion reaction, and DT fuel is assumed as corresponding nuclear fusion fuel, however, the present invention is also applicable to other energy lines, nuclear fusion reactions, and fuels. FIG. 1 is a block diagram showing a functional configuration of a device 1 for determining irradiation coordinates according to a preferred embodiment of the present invention, FIG. 2 is a hardware block diagram showing hardware configuration of the device 1 for determining irradiation coordinates, and FIG. 3 is a perspective view of an information processing device that operates as the device 1 for determining irradiation coordinates. As shown in FIG. 1, the device 1 for determining irradiation coordinates functionally includes an input section 101, an initial arrangement section (initial arrangement means) 102, a coordinate analysis section (coordinate analysis means) 103, a potential evaluation section (potential evaluation means) 104, an optimal coordinate determination section (irradiation coordinate deriving means) 105, and an output section 106. The information processing device 30 shown in FIG. 2 and FIG. 3 operates as this device 1 for determining irradiation coordinates. The information processing device 30 includes a reading device 12 such as a floppy disk drive unit, a CD-ROM drive unit, and a DVD drive unit, a working memory (RAM) 14 in which an operating system is resident, a memory 16 that stores programs stored in a recording medium 10, a display unit 18 such as a display, a mouse 20 and a keyboard 22 as input devices, a communication device 24 for transmitting and receiving data, etc., and a CPU 26 for controlling executions of the programs. The information processing device 30 becomes accessible to a program stored in the recording medium 10 from the reading device 12 when the recording medium 10 is inserted into the reading device 12, and is allowed to operate as the device 1 for determining irradiation coordinates according to the present invention by this program. In detail, the functions realized by the respective sections shown in FIG. 1 are realized by operating the communication device 24, the mouse 20, the keyboard 22, and the display 18 under control of the CPU 26 by reading a predetermined program on the hardware of the CPU 26 and the memory 16, etc., shown in FIG. 2, and reading and writing data from and on the working memory 14 and the memory 16. Hereinafter, functions of the respective sections of the device 1 for determining irradiation coordinates are described in detail. The input section 101 accepts an input of the number of irradiation coordinates of energy lines in a nuclear fusion device to be designed. Specifically, the input section 101 accepts an input of information on the number of irradiation coordinates using the mouse 20 and the keyboard 22, and stores the accepted data on the number of irradiation coordinates in the working memory 14, etc. The initial arrangement section 102 sets initial coordinates r0i (i=1, . . . , NB) of electric charges Qi (i=1, . . . , NB) as many as the number of irradiation coordinates NB based on the number of irradiation coordinates NB (NB is a positive integer) accepted by the input section 101. In detail, the initial arrangement section 102 includes a random number generation section 102a, and sets a spherical surface S0 centered on an origin O in a virtual space, and sets the initial coordinates r0i (i=1, . . . , NB) at random positions on the spherical surface S0 while referring to random numbers generated by the random number generation section 102a. Accordingly, the initial arrangement section 102 virtually arranges NB electric charges Qi at the positions represented by r0i on the spherical surface S0. The coordinate analysis section 103 analyzes coordinates of NB electric charges Qi whose initial coordinates r0i were set by the initial arrangement section 102 in time series. Specifically, the coordinate analysis section 103 calculates coulomb forces acting among the electric charges Qi when the charge amount of the electric charges Qi (i=1, . . . , NB) is set to q. Further, the coordinate analysis section 103 adds a condition that the electric charges Qi are constrained onto the spherical surface S0 (\|ri\|=1, i=1, . . . , NB) and temporally integrates NB systems of equations of motions relating to the coordinates ri (i=1, . . . , NB) of the electric charges Q by using the following equation (1): [ Numerical ⁢ ⁢ equation ⁢ ⁢ 1 ] ⅆ 2 ⁢ r j ⅆ t 2 = ∑ i = 1 N B ⁢ q 2  r → i - r → j  2 - Co ⁢ ⅆ r → j ⅆ t ⁢ ( j = 1 , … ⁢ , N B ) ( 1 ) to calculate all coordinates ri in time series. Here, the second term of the right side of the equation (1) is an artificial viscosity term for preventing micro-vibration of the solution. The potential evaluation section 104 determines a timing at which the potential energies of all electric charges Qi were stabilized based on the coordinates ri of the NB electric charges Qi analyzed by the coordinate analysis section 103. In detail, each time the coordinates ri are calculated by the coordinate analysis section 103, the potential evaluation section 104 calculates the sum EP of potential energies of the NB electric charges Qi according to the following equation (2): [ Numerical ⁢ ⁢ equation ⁢ ⁢ 2 ] E P = ∑ i = 1 N B ⁢ ∑ j = 1 ⁢ ( i ≠ j ) N B ⁢ q 2  r → i - r → j  ( 2 ) Then, the potential evaluation section 104 determines whether the potential energies of the electric charges Qi have been stabilized by determining whether a temporal change of the sum EP is not more than a predetermined threshold ThP. For example, it is determined whether a difference between a sum EP based on the coordinates ri previously calculated and a sum EP based on coordinates ri calculated at this time is not more than the threshold ThP=10−16. When the potential evaluation section 104 determines that the potential energies have been stabilized, the optimal coordinate determination section 105 identifies coordinates ri of the NB electric charges Qi at the stabilization timing. Then, the optimal coordinate determination section 105 derives these coordinates ri as coordinates corresponding to optimal irradiation coordinates of energy lines when the nuclear fusion target is arranged at the center of the spherical surface S0. Then, the optimal coordinate determination section 105 transmits the derived coordinates ri to the output section 106, and the output section 106 outputs the coordinates in a predetermined output format such as a table data format, etc., to the display 18 and the communication device 24. Next, a method of determining irradiation coordinates using the device 1 for determining irradiation coordinates is described with reference to FIG. 4. FIG. 4 is a flowchart showing steps of processing of determining irradiation coordinates by the device 1 for determining irradiation coordinates. First, the input section 101 of the device 1 for determining irradiation coordinates accepts an input of the number of irradiation coordinates NB of energy lines relating to the nuclear fusion device to be designed (Step S201). Next, the initial arrangement section 102 randomly sets initial coordinates r0i of the electric charges Qi (i=1, . . . , NB) as many as the number of irradiation coordinates NB on the spherical surface S0 by generating random numbers (Step S202). Thereafter, the coordinate analysis section 103 calculates coordinates ri of the electric charges Qi in time series by temporally integrating N systems of equations of motions in consideration of coulomb forces between the electric charges Qi (i=1, . . . , NB) (Step S203). Then, the coordinate analysis section 103 sets the time of coordinates ri to be calculated next as the time of the next step (Step S204). Further, the potential evaluation section 104 determines whether a temporal change of the sum EP of potential energies of all electric charges Qi is not more than the threshold ThP, and transmits the determination result to the optimal coordinate determination section 105 (Step S206). As a result, when a temporal change of the sum EP is not more than the threshold ThP (Step S206: YES), the optimal coordinate determination section 105 determines NB coordinates ri calculated at this timing as coordinates corresponding to the optimal irradiation coordinates of energy lines when the nuclear fusion target is arranged at the center of the spherical surface S0. At the same time, the output section 106 outputs information on the optimal irradiation coordinates to the display 18, etc., and the process is ended (Step S207). On the other hand, when a temporal change of the sum EP is more than the threshold ThP (Step S206: NO), the process is returned to Step S203 and the calculation of coordinates ri of the electric charges Qi relating to the time of the next step is repeated. Next, an example of a nuclear fusion device designed and manufactured by using the above-described method of determining irradiation coordinates is described. First, the optimal irradiation coordinates of energy lines derived by the device 1 for determining irradiation coordinates when the number of irradiation coordinates NB=4 is set are as shown in the following Table 1. TABLE 1Pattern APattern Bθ [°]φ [°]θ [°]φ [°]83.353151.5943.643286.321.24315051.30763.36996.647291.1472.996180.5496.647111.1443.64316.29683.353331.59128.69109.3696.64721.143128.69289.3669.92124.29107172.19110.0848.44472.996270.5483.353241.59136.3666.435158.76112.74136.36246.43158.76202.7472.9960.54248158.7622.735136.36156.4383.35361.588128.69199.3669.9234.28651.307153.37158.76292.74128.6919.36121.24359.99651.307333.3721.243240136.36336.43110.08138.44107262.19110.08228.4410782.188110.08318.4443.643196.396.647201.14107352.1969.92304.2943.643106.369.92214.2972.99690.54221.24333051.307243.37The coordinates derived here are represented by the polar coordinates (θ, φ) on the virtual spherical surface S0. FIG. 5 is a plan view showing a structure of a nuclear fusion device 201 manufactured based on the optimal irradiation coordinates in this case, and FIG. 6 is a conceptual diagram for describing irradiation coordinates of energy lines in the nuclear fusion device 201 of FIG. 5. As shown in FIG. 5, the nuclear fusion device 201 includes a spherical target 202 and laser light irradiation sources 203 that are arranged at 48 points around the spherical target 202 and irradiate laser lights onto the spherical target 202. Here, in FIG. 5, only laser light irradiation sources 203 as a part of the 48 laser light irradiation sources are illustrated. The laser light irradiation sources 203 are provided at positions corresponding to optimal irradiation coordinates on the assumption that the spherical target 202 is positioned at the center of the spherical surface S0. In detail, the laser light irradiation sources 203 are arranged so as to become capable of irradiating laser lights L1 that advance toward the center of the spherical target 202 by passing through virtual coordinate points PA and PB on the spherical surface S0 derived by the device 1 for determining irradiation coordinates. These coordinate points that determine the optimal coordinates of the laser light irradiation sources 203 are divided into two groups of coordinate patterns of 24 coordinate points PA and PB, and coordinate points PA corresponding to the pattern A in Table 1 form 6 squares each consisting of four points adjacent to each other, and coordinate points PB corresponding to the pattern B in Table 1 form eight equilateral triangles each consisting of three points adjacent to each other. As shown in FIG. 6, the laser light irradiation sources 203 are arranged so that the gravity centers GB of the eight equilateral triangles formed by the coordinate points PB are positioned on the extensions of the center passing trough the centers of the surfaces of the regular octahedrons S1 centered on the spherical target 202 and the gravity centers GA of the six squares formed by the coordinate points PA are positioned on the extensions of the center passing trough the centers of the apexes of the regular octahedrons S1. Further, in Table 2, the optimal irradiation coordinates of energy lines derived by the device 1 for determining irradiation coordinates when the number of irradiation coordinates NB=24 is set are shown. In a nuclear fusion device to which the number of irradiation coordinates=24 of energy lines is applied, as in the case of the nuclear fusion device 201, laser light irradiation sources are provided at positions corresponding to 24 optimal irradiation coordinates when it is assumed that the spherical target is positioned at the center of the spherical surface S0. TABLE 2θ [°]φ [°]86.757357.57129.7412.2283.162117.3596.241281.7154.61526.899110.6201.4114.71321.1993.323161.9924.335214.95155.24303.67126.78249.99151.41186.7565.008198.0952.639269.61154.4572.26228.425333.8267.6376.73983.213237.850.489146.86112.9682.80169.087318.3126.13787.108125.74132.9697.30442.137 Hereinafter, the optimal irradiation coordinates derived by the device 1 for determining irradiation coordinates shown in Tables 1 and 2 and the optimal irradiation coordinates derived by the device 1 for determining irradiation coordinates when the number of irradiation coordinates NB=72 is set are shown from another viewpoint. In the case of the number of irradiation coordinates NB=24, the coordinates (θ, φ) obtained by applying the following equations:θi+4m+8k=(−1)mθi+180 m φi+4m+8k=(−1)mφi+95.6162 m+120 k i=1, 2, 3, 4; m=0, 1; k=0, 1, 2to the data shown in the following Table 3, are the optimal irradiation coordinates to be derived by the device 1 for determining irradiation coordinates. TABLE 3NB = 24NB = 48NB = 72iθi [°]φi [°]θi [°]φi [°]θi[°]φi[°]126.248000.00000021.243020.00000024.4917184.24238252.5622655.8426443.6429643.6998141.3065048.91327367.23147345.767251.3071786.6262349.8753687.02248484.3748325.6215069.9195925.7093463.4349562.41641572.9962459.4530667.5280035.82484683.3532388.4080277.9053083.44693787.2793356.58353 In the case of the number of irradiation coordinates NB=48, the coordinates (θ, φ) obtained by applying the following equations:θi+6m+12k=(−1)mθi+180 m φi+6m+12k=(−1)mφi+37.2604 m+90 k i=1, 2, . . . , 6; m=0, 1; k=0, 1, 2, 3to the data shown in Table 3, are the optimal irradiation coordinates to be derived by the device 1 for determining irradiation coordinates. Further, in the case of the number of irradiation coordinates NB=72, the coordinates (θ, φ) obtained by applying the following equations:θi+7m+14k=(−1)mθi+180 m φi+7m+14k=(−1)mφi+88.8328 m+72 k i=1, 2, . . . , 7; m=0, 1; k=0, 1, 2, 3, 4(θ71, φ71)=(0, 0), (θ72, φ72)=(180, 0)to the data shown in Table 3, are the optimal irradiation coordinates to be derived by the device 1 for determining irradiation coordinates. With the above-described method of determining irradiation coordinates and device 1 for determining irradiation coordinates, by the information processing device 30, electric charges Qi are virtually arranged at the initial coordinates of the number of irradiation coordinates NB on the spherical surface S0, the coordinates ri of the electric charges Qi are analyzed in time series, and based on coordinates ri at the timing at which the sum EP of potential energies of the electric charges Qi was stabilized, irradiation coordinates of energy lines when the nuclear fusion target is arranged at the center of the spherical surface S0 are derived. With a nuclear fusion device manufactured by using this device 1 for determining irradiation coordinates, the uniformity in irradiation intensity of laser lights onto nuclear fusion fuel can be improved with a smaller number of coordinates of laser lights as compared with the conventional case. FIG. 7 is a graph showing results of simulation of irradiation uniformity of the nuclear fusion device according to the present embodiment. In this drawing, power non-uniformity on the horizontal axis indicates the degree of intensity difference between laser lights of a plurality of coordinates, and irradiation uniformity on the vertical axis indicates a value obtained by dividing a standard deviation of laser light irradiation intensities on the spherical surface S0 by a mean value thereof. The characteristic C1 shows the case of the number of irradiation coordinates NB=48 in the present embodiment, the characteristic C2 shows the case of the number of irradiation coordinates NB=24 in the present embodiment. On the other hand, the characteristic C3 shows the case of the number of irradiation coordinates equals 60 in a conventional device (OMEGA 60, University of Rochester-Laboratory for Laser Energetics), and the characteristic C4 shows the case of the number of irradiation coordinates equals 24 in a conventional device (OMEGA 24, University of Rochester-Laboratory for Laser Energetics). From these results, it is understood that, in the present embodiment, the irradiation uniformity is improved with irradiation coordinates the number of which is the same as or smaller than in the conventional case. It was further confirmed that no laser beams were opposing each other with respect to the center of the spherical surface S0 when the number of irradiation coordinates NB was larger than 20 in the case of irradiation coordinates of laser lights obtained by the method of determining irradiation coordinates and the device 1 for determining irradiation coordinates according to the present embodiment. Therefore, deterioration in performance due to damage caused by opposing laser light sources can be avoided. Further, in the present embodiment, it is determined whether a temporal change of the sum EP of potential energies of the electric charges Qi is not more than the threshold ThP, so that irradiation coordinates with improved laser light irradiation uniformity can be efficiently derived within limited ranges of operation performance and operation time. With a nuclear fusion device manufactured by using the method of determining irradiation coordinates and the device 1 for determining irradiation coordinates, uniformity in irradiation intensity of energy lines onto a nuclear fusion target is improved, so that inertial confinement fusion can be stably caused. Here, preferably, it is determined in the potential evaluation step whether a temporal change of the sum of potential energies of a predetermined number of electric charges at the timing is not more than a predetermined value, or the potential evaluation means determines whether a temporal change of the sum of potential energies of the predetermined number of electric charges at the timing is not more than a predetermined value. In this case, irradiation coordinates with improved energy line irradiation uniformity can be efficiently derived. The present invention is applied to a method of determining nuclear fusion irradiation coordinates and a device for determining nuclear fusion irradiation coordinates that determine irradiation coordinates of energy lines onto nuclear fusion fuel, and a nuclear fusion device manufactured by using these method and device, and can efficiently improve uniformity of energy lines to be irradiated. 1: Device for determining irradiation coordinates, 30: Information processing device, 102: Initial arrangement section (initial arrangement means), 103: Coordinate analysis section (coordinate analysis means), 104: Potential evaluation section (potential evaluation means), 105: Optimal coordinate determination section (irradiation coordinate deriving means), 201: Nuclear fusion device, 202: Spherical target (nuclear fusion target), 203: Laser light irradiation source (energy line source), S0: Spherical surface
	abstract	A radiation detector has a main body (1), and a radiation detection probe (2) detachably attached to the distal end of the main body (1). The probe (2) includes a detection unit (3) accommodating a radiation detection element (7), a cap-shaped shield member (6) mounted to the detection unit (3) so as to cover the distal end of the detection unit (3), and a probe cover (4) accommodating the detection unit (3) and the shield member (6). A connector (10) onto which the probe (2) is adapted to be screwed is provided on the distal end of the main body (1). A collimator (6A) for collimating incident radiation is provided on the distal end of the shield member (6).
	claims	1. A radiant energy emitting device, comprising:an outer housing including at least one aperture there through, the housing being operationally configured to (1) receive and contain radiant energy therein, and (2) emit radiant energy out through the aperture to a target surface;an energy emission means; anda sensor means disposed along the entire perimeter of the aperture of the housing, the sensor means being in communication with the energy emission means and operationally configured to detect the spatial relationship between the sensor means and the target surface along the perimeter of the aperture,said spatial relationship determining activation of the energy emission means. 2. The device of claim 1, wherein the sensor means includes a projected field sensor. 3. The device of claim 2, wherein the sensor means is a projected capacitive sensor. 4. The device of claim 2, wherein the sensor means is operationally configured to detect the target surface through a non-electrically conductive medium. 5. The device of claim 2, wherein the sensor means is a continuous sensor having a void there through. 6. The device of claim 2, wherein the sensor means is operationally configured to allow for passage of radiant energy there through. 7. The device of claim 1, wherein the sensor means includes a proximity sensor. 8. The device of claim 1, wherein the sensor means is a continuous sensor having a void there through. 9. The device of claim 8, wherein the perimeter of the void is about equal in length to the perimeter of the aperture. 10. The device of claim 1, further comprising a manual energy activation means for activating energy emission of the device. 11. The device of claim 1, wherein the sensor means is operationally configured for unattenuated radiant energy emission during device operation. 12. The device of claim 1, including a pistol-type grip having, a trigger means for activating energy emission of the device. 13. The device of claim 1, wherein the device is operationally configured to receive radiant energy from light-emitting diodes. 14. A device for emitting radiant energy onto a target surface, comprising:an outer housing including at least one aperture there through;an energy source for generating radiant energy, the energy source being in communication with the housing;an activation means in communication with the energy source; anda sensor means disposed along the entire perimeter of the aperture of the housing, the sensor means being in communication with the activation means and operationally configured to detect the spatial relationship between the sensor means and the target surface along the perimeter of the aperture, said spatial relationship determining, operation of the activation means; wherein the housing is operationally configured to emit radiant energy out through the aperture to the target surface. 15. The device of claim 14, wherein the sensor means includes a projected held sensor. 16. The device of claim 15, wherein the sensor means is operationally configured to detect the target surface through a non-electrically conductive medium. 17. The device of claim 14, wherein the radiant energy has a wavelength from about 10 nm to about 400 nm. 18. A method for delivering radiant energy to a target surface while preventing unintended radiant energy emission, comprising:providing a radiant, energy emitting device, comprising (A) an outer housing including at least one aperture there through, the housing being operationally configured to (1) receive and contain radiant energy therein, and (2) emit radiant energy out through the aperture to a target surface;(8) an energy emission means; and (C) a sensor means disposed about the entire aperture of the housing, the sensor means being in communication with the energy emission means and operationally configured to detect the spatial relationship between the sensor means and the target surface 360 degrees along the perimeter of the aperture, said spatial relationship determining activation of the energy emission means;directing the device toward a target surface until the sensor means detects the spatial relationship between the sensor means and the target surface; andactivating the energy emission means for delivering radiant energy to the target surface. 19. The method of claim 18 wherein the radiant energy is provided by light-emitting diodes. 20. The method of claim 18 wherein radiant energy is delivered in an auto-dosage-sequence. 21. The method of claim 18 wherein the sensor means includes a projected field sensor.
	description	This application is a continuation of, and claims benefit under 35 USC 120 to U.S. Ser. No. 13/307,550, filed Nov. 30, 2011, which is a continuation of Ser. No. 12/700,351, filed Feb. 4, 2010, now U.S. Pat. No. 8,089,707, which is a continuation of U.S. Ser. No. 10/595,583, filed Apr. 28, 2006, now U.S. Pat. No. 7,684,125, now U.S. Pat. No. 7,684,125, which claims benefit under 35 USC 371 of international application PCT/EP2003/014551, filed Dec. 18, 2003, which claims benefit of German Application No. 103 50 545.8, filed Oct. 29, 2003. The contents of these applications are hereby incorporated by reference in their entirety. 1. Field of the Invention The invention relates to an optical imaging device, in particular an objective for microlithography in the field of EUVL for producing semiconductor elements, having a beam path, a plurality of optical elements and a diaphragm device with an adjustable diaphragm opening shape. 2. Description of the Related Art It is generally known to use various diaphragms as system diaphragms in optical imaging devices. The diameter of the light beam bundle in the beam path of the optical imaging device can be varied by means of these diaphragms, of which the opening diameter can be varied, in particular. So-called iris diaphragms, which have at least four—but mostly more—thin blades which are generally in the shape of a sickle and are supported at one end rotatably in a fixed mount are particularly widespread. In this arrangement, the other end is provided as guiding device with a pin which is inserted in a groove or slot of a rotatable ring such that the rotation of the rotatable ring moves the blades in such a way that the remaining opening diameter for the diaphragm can be varied. DE 101 11 299 A1 discloses such an iris diaphragm, in particular for an exposure objective in semiconductor lithography, having a plurality of blades which are guided with the aid of guide elements, and can be moved by at least one drive device for the purpose of adjusting the diaphragm opening. The guide elements are designed such that the blades can be moved in an at least approximately linear fashion in a radial direction in relation to the optical axis of the iris diaphragm. DE 199 55 984 A1 discloses a further diaphragm for stopping down an optical imaging device. Known diaphragms, in particular the iris diaphragms which can be adjusted continuously via blades, are less suitable for use in stopping down an optical system used in microlithography, chiefly in the field of EUVL, since more stringent demands are placed here on the installation space available, which these cannot satisfy because of their construction. It is therefore the object of the present invention, to create an optical imaging device of the type mentioned at the beginning which can be stopped down with the aid of a diaphragm which requires only a small installation space. This object is achieved according to the invention by virtue of the fact that the diaphragm device has a diaphragm store with a plurality of different diaphragm openings with fixed shapes in each case, which can be introduced into the beam path. The measures according to the invention create in a simple and advantageous way an optical imaging device having a diaphragm mechanism in the case of which the shapes of the diaphragm openings are permanently determined and can be stored in a very small space. There are no restrictions on the geometry of the shapes of the diaphragm openings, and so both circular and elliptical or other geometries can be used for the diaphragm openings. By contrast with the known blade-type iris diaphragms, the masses to be moved are comparatively small, and so changing the diaphragms in the optical imaging device can be undertaken very quickly. The most varied types of diaphragms can be brought into use by means of the existing diaphragm store with diaphragm openings. It is very advantageous when the diaphragm store is designed as a revolving disc diaphragm stack, in particular arranged outside the optical imaging device, with a plurality of revolving disc diaphragms which are provided with diaphragm openings and are, in particular, accommodated in separate plug-in units. These measures yield a further space-saving design of the diaphragm device, in particular outside the optical imaging device, as a result of which comparatively many different revolving disc diaphragms can be stored in the revolving disc diaphragm stack. By contrast with an inner arrangement, the arrangement of the diaphragm device outside the optical imaging device additionally minimizes contamination of the optical imaging device by the diaphragm device. Moreover, the diaphragm device can be dynamically decoupled from the optical imaging device such that no disturbing vibrations are introduced by the diaphragm device to the optical elements arranged in the optical imaging device. Moreover, it can be provided in one structural configuration of the invention that a sheet-metal strip which is wound onto two rollers and held tensioned is provided as a diaphragm store, the sheet-metal strip having a plurality of, in particular, various diaphragm openings of fixed shapes, and it being possible by rotating the rollers to adjust the diaphragm setting by varying the diaphragm openings. This results in a very highly dynamic adjustment of the various diaphragms, which can be stored in a very small space. The masses to be moved are comparatively small and there are no restrictions on the geometry of the diaphragm openings. Changing diaphragms can be undertaken speedily. Advantageous refinements and developments of the invention arise from the further subclaims. Various embodiments of the invention are explained in principle below with the aid of the drawings. FIG. 1a shows a detail of a projection objective 1 for use in the field of EUVL, with its typical beam path 2 between mirrors 3 arranged on a housing 1a, illustrated by dashes, of the projection objective 1, and an object plane 4 (explained in more detail in FIG. 14). Arranged in the beam path 2 is a diaphragm 5 with a diaphragm opening 6 which serves to stop down the light beam of the projection objective 1. As may be seen, stringent requirements are placed on the nature and the installation space of the diaphragm 5 here. This is required principally on a side 5′ of the diaphragm 5 that is emphasized by a circle. Consequently, the diaphragm opening 6 should be decentral as illustrated in FIG. 1b. This requisite arrangement of the diaphragm opening 6 on, the diaphragm 5, as well as the small installation space in the projection objective 1 complicate the use of conventional, continuously adjustable iris diaphragms (for example, by means of blades) in the case of such a projection objective 1, in particular in the case of operating wavelengths in the field of EUVL. FIG. 2 shows the detail of the projection objective 1 in a design with a diaphragm device 7 with a revolving disc diaphragm stack 7a, 7b, which has individual diaphragms 5, designed as revolving disc diaphragms, with fixed geometries (see FIG. 1b) stashed vertically one above another. The diaphragm openings 6 can also have elliptical or other shapes instead of the circular shape illustrated. The revolving disc diaphragms 5 are preferably brought into the beam path 2 of the projection objective 1 to an operating position 9 (indicated by dots) provided therefor via directions indicated by arrows 8. As may be seen from FIG. 1b, the revolving disc diaphragms 5 are shaped in such a way that they have a thin rim on the side of the neighbouring light beam, and a broad rim over the remainder of the circumference. As may be seen in FIGS. 3a to 3c, the optimum physical spacing of revolving disc diaphragms 5a to 5c is different for different sizes of diaphragm in relation to the mirrors 3 arranged upstream thereof in the beam direction. In order to be able to ensure this when mounting the revolving disc diaphragms 5a to 5c at a uniform height h with reference to the mirrors 3, the latter are provided with different heights with reference to toe ranges 10 of their mountings. As illustrated in FIG. 4a, the revolving disc diaphragm stack 7a has a plurality of revolving disc diaphragms 5 which are accommodated in separate plug-in units 11. Each plug-in unit 11 can be rotated out (indicated by the arrow 12 in FIG. 4a) individually by means of an articulated element (not illustrated) common to all the plug-in units 11, such that in each case one revolving disc diaphragm 5 can be rotated out in order subsequently to be lifted (indicated in FIG. 4a by the dotted arrow 8) into the beam path 2 of the projection objective 1 to its operating position 9, as explained at a later point in time. The swivelling movement of the plug-in units 11 can be accomplished by means of a gearwheel drive which is fitted on a lifting mechanism or a module housing and can be arranged in such a way that at moves the gearwheel teeth as the plug-in unit 11 passes. Alternatively, in other exemplary embodiments it would also be possible to provide other drive mechanisms, in particular friction wheels, magnetic clutches or special electric motors with rotors which are installed in the plug-in units 11. In the present exemplary embodiment, the plug-in units 11 have a uniform overall height. In other exemplary embodiments, however, these can also differ in order to be able to use various sizes of diaphragm (compare FIGS. 3a to 3c). After the operating position 9 of the revolving disc diaphragm 5 is reached, the latter is coupled to a holding device or to a stop 13. The holding device 13 permits a repeatably accurate positioning of the revolving disc diaphragms 5 in the micrometer range. This reduces the accuracy requirements for the separate plug-in units 11, and also for the overall lifting mechanism (indicated by the arrow 8). As may be seen from FIG. 4b, instead of lifting the revolving disc diaphragms 5 to the operating position 9 it is also possible in a further embodiment to move a revolving disc diaphragm stack 7b vertically (indicated by the arrow 8′) until the appropriate revolving disc diaphragm 5 has reached substantially the same height as the holding device 13, after which the plug-in unit 11 with the appropriate revolving disc diaphragm 5 is rotated out and coupled to the holding device 13 after a possible additional slight vertical movement (arrow 8). This embodiment has the advantage that the diaphragm exchange mechanism requires only very little space in front of the mirror 3, the result being to release this space for additional systems (mirror cleaning systems etc.). An operating range 14 of the vertically displaceable revolving disc diaphragm stack 7b is illustrated by dashes or dots and dashes in FIG. 4c, as is a free region for additional systems 15. Especially for the field of EUVL, projection objectives 1 are very sensitive to movements of their individual optical elements, for example mirror 3, both relative to one another and relative to the structure of their mountings. In order to minimize the transmission of interfering vibrations, the projection objective 1 is isolated from vibrations. Moreover, the individual elements inside the projection objective 1 are connected to one another rigidly (with a high natural frequency) in such a way that they move with one another as a rigid body when excited by any residual vibrations, which are usually of low frequency. It is a complicated undertaking to create an embodiment of the overall diaphragm device 7 with a sufficiently high natural frequency, since relatively large masses have to be moved and the installation space is restricted. Consequently, dynamic movements (vibrations) would be transmitted to the overall projection objective 1 by the diaphragm device 7. The relative positioning of the diaphragm 5 in relation to the remaining optical elements of the projection objective 1 is less critical in general, however. A possible solution to this problem is for the entire diaphragm device 7 to be mounted on, a separate structure dynamically decoupled from the projection objective 1, but this would make positioning the diaphragm exactly in the projection objective 1 more difficult. A further solution consists in separating the selected revolving disc diaphragm 5 with the holding device 13 from the remainder of the diaphragm device 7 (revolving disc diaphragm stacks 7a, 7b, plug-in units 11, lifting mechanism, housing, etc.) and arranging them on different structures, the holding device 13 being fastened directly on the optical imaging device or on the projection objective 1. The remainder of the diaphragm device 7 can be mounted on a separate structure. A further possible solution consists in fastening both the holding device 13 and the lifting mechanism 16 on the projection objective 1, while the remainder of the diaphragm device 7 is mounted on a separate structure. The holding device 13 ensures that the revolving disc diaphragm 5 is positioned accurately relative to the projection objective 1 and in six degrees of freedom. Furthermore, there is also a need to hold or lock the revolving disc diaphragms 5 in the holding device 13 against the gravity force and other interfering forces. In order to prevent particles from contaminating the mirror surfaces, the revolving disc diaphragm 5 should be locked as gently as possible. As sketched in FIG. 5, the revolving disc diaphragm 5 is conveyed by means of a lifting device 16 from a removal, position into its operating position 9, and held there in the holding device 13. In the case of the diaphragm device 7 illustrated in FIG. 5, use was advantageously made of mainly rotary mechanisms in the diaphragm exchange mechanism since, by contrast with translation mechanisms, fewer particles causing contamination, for example, by friction forces, are produced. As illustrated further in FIG. 5, the essentially constant force for holding the revolving disc diaphragm 5 in the holding device 13 is effected in a simple and advantageous way by spring elements 17 of low stiffness. The spring elements 17 should be precompressed in order to avoid a large compression deflection of the spring elements 17 relative to the operating position 9 of the revolving disc diaphragm 5. An arrow 18 indicates the dynamic decoupling or the vibrational decoupling of the separately-mounted housing 1a of the projection objective 1 (indicated by dashes) and of the remainder of the diaphragm mechanism (dashed box 19), likewise mounted separately. FIGS. 6a to 6c illustrate various embodiments of the holding device 13 for fixing and/or positioning the revolving disc diaphragm 5. As may be seen from FIG. 6a, a holding device 13a has a permanent magnet 20 and a soft iron core 21 with a coil winding 22. The revolving disc diaphragms 5 (not illustrated in more detail here) likewise have a soft iron core 21′ on the opposite side and are thereby held via magnetic forces. This has the advantage that there are only a few or no open mechanically moveable parts which could lead to further instances of particle contamination. As is illustrated in FIG. 6b, a holding device 13b is provided on a part 23, and has a static part 23′ and the permanent magnet 20. The revolving disc diaphragm 5 has the soft iron core 21 by means of which the revolving disc diaphragm 5 is held on the holding device 13b. In addition, the lifting device 16 (not illustrated in more detail in FIG. 6b) has a switchable electromagnet 20′ which is switched in the event of an exchange of diaphragms in such a way that the diaphragm is loosened from the holding device 13b. Illustrated in FIG. 6c is a third embodiment of a holding device 13c which corresponds in essence to the holding device 13b from FIG. 6b. A soft spring element 24 which engages in a cut-out 25 in the revolving disc diaphragm 5 has been inserted here in addition. FIG. 7a shows a holding device 13d with a revolving disc diaphragm 5d. A mirror contamination monitoring means is provided here, in addition. This is effected by fine tungsten lead wires 26 which are guided via the opening in the revolving disc diaphragm 5. The revolving disc diaphragm 5d is fabricated for this purpose from an insulating material such as, for example, a ceramic or similar. The electrical connection with the tungsten lead wires 26 is achieved by three contact points on bearing points 27 of the revolving disc diaphragm 5d. FIG. 7b shows an alternative embodiment of a contamination monitoring means. Here, the tungsten lead wires 26 are integrated in the lifting device 16. As may be seen from FIG. 8, the vertically displaceable revolving disc diaphragm stack 7b is arranged outside the projection objective 1 or the housing 1a thereof. This protects the projection objective 1 against contamination by the revolving disc diaphragm stack 7b. The revolving disc diaphragm stack 7b is provided with a feeder device 28 which is designed as a moveable robot gripper arm, removes the corresponding revolving disc diaphragm 5 from the revolving disc diaphragm stack 7b and inserts it into the beam path 2 of the projection objective 1 through an opening 29 provided for the purpose. An additional lifting device 16′ (illustrated in a simplified fashion), likewise arranged outside the projection objective 1, conveys the revolving disc diaphragm 5 to the holding device 13, it then being fixed in its operating position 9. As already described above, the diaphragm exchange mechanisms and the lifting device 16′ can be mounted in a dynamically decoupled fashion on different structures. Soft springs 17 of the lifting device 16′ ensure a dynamically decoupled connection. The opening 29 in the projection objective 1 or the housing 1a is closed during operation. In FIG. 9, a lifting device 16″ is introduced and mounted inside the housing 1a of the projection objective 1. Surfaces which slide or roll on one another are reduced to an absolute minimum in order to avoid or to minimize particle contamination. This can be implemented by using solid joints and appropriate actuators (voice coil actuator, Lorentz actuator). Surfaces are minimized in order to avoid instances of molecular contamination and, moreover, use is made only of suitable materials with low degassing rates (steels, no plastics or lubricants). Lubrication on bearings can be dispensed with by using solid joints. The mass is to be kept small or the natural frequency of the lifting device 16″ is to be kept as high as possible in order not to impair the structure of the projection optics dynamically. As may further be seen from FIG. 9, the lifting device 16″ has the holding device 13 for the revolving disc diaphragm 5. The revolving disc diaphragm 5 constructed as sheet metal is situated on the feeder device 23. The feeder device 28 brings the revolving disc diaphragm 5 into the projection optics below the mirror 3. The revolving disc diaphragm 5 is lifted from the feeder device 28 when the lifting device 16″ is raised. The lifting device 16″ drives against an inner stop. The revolving disc diaphragm 5 lies on the holding device 13 because of its own weight. Raising upwards can be prevented for example by means of a protective cover (compare FIG. 10a). The revolving disc diaphragm 5 cannot then fall out or collide with the mirror 3. The following FIGS. 10a to 10c show structural configurations 16a, 16b, 16c of the lifting device 16″ from FIG. 9. They have voice coil actuators (not shown in more detail) for manipulation. Rotary joints are respectively designed as solid joints 30. As illustrated in FIG. 10a, a protective cover 31 prevents the lifting device 16a, constructed as a rocker, from raising the revolving disc diaphragm 5. The lifting devices 16a to 16c have internal end stops which prescribe the respective end positions of the lifting movement. The steering movement of the lifting device 16a is indicated by an arrow 32. FIG. 10b shows the lifting device 16b, which is designed as a set of scales and has a parallelogram guide. It is advantageous in this case that the revolving disc diaphragm 5 can be moved upwards virtually vertically. A pantographic lifting device 16c is sketched in FIG. 10c. FIG. 11 shows the feeder device 28 designed as a robot gripper arm. The revolving disc diaphragm 5 can be withdrawn from below by the lifting device 16a, 16b, 16c from the receptacle of the feeder device 28. A locking mechanism 33 fastens the revolving disc diaphragm 5 during transport. In other exemplary embodiments the revolving disc diaphragm 5 can also be configured symmetrically such that fitting may be done from both sides. The feeder device 28 can, in addition, be designed as a double gripper, that is to say with two receptacles for two revolving disc diaphragms 5 (not illustrated). The time for changing diaphragms is thereby substantially shortened. During changing, the feeder device 28 moves with a revolving disc diaphragm 5 into the projection optics of the projection objective 1. The exchange revolving disc diaphragm 5, which is already located in the projection optics, is deposited on the second (empty) receptacle. The new revolving disc diaphragm 5 would be taken over by the lifting device 16a, 16b, 16c. During a change of diaphragm, the feeder device 28 would therefore have to move one less time into the projection optics. A further embodiment of a diaphragm device 7′ for the projection objective 1 is illustrated in FIG. 12. The great advantage here is the improved dynamics of the change of diaphragm in conjunction with a small required installation space. As may be seen, an incident light beam 34 is stopped down by a sheet-metal strip 7c. The latter is provided with openings 35 which, depending on optical requirement exhibit an optimum fixed geometry. The further openings 35 are incised adjacently as diaphragms on the sheet-metal strip 7c. The sequence of the openings 35 can be varied in order to ensure optimum speed in changing diaphragms, depending on the requirements. The sheet-metal strip 7c is wound onto two rollers 36. These are driven and tensioned such that the sheet-metal strip 7c has no “folds”. Two additional tensioning and guiding rollers 37 are fitted in order to avoid diaphragms which shift in the light direction. As a result, the changing diameter of the rollers 36 (including wound-on sheet-metal strip 7c) is, in particular, not rendered noticeable by an oblique position of the sheet-metal strip 7c. The optimum position of the diaphragm openings 35 can be measured, using appropriate sensors (not illustrated) via markings 38 at the edge of the sheet-metal strip 7c. However, other methods are also conceivable in further exemplary embodiments. A front view of the diaphragm device 7′ from FIG. 12 is illustrated in FIG. 13. As may be seen from FIG. 14, an EUV projection exposure machine 40 has a light source 41, an EUV illuminating system 42 for illuminating a field in the object plane 4 in which a pattern-bearing mask is arranged, and the projection objective 1 with the housing 1a and the beam path 2 (indicated by dashes) for imaging the pattern-bearing mask in the object plane 4 onto a photosensitive substrate 43. The diaphragm 5 for stopping down the projection objective 1 is indicated by dots.
	abstract	A nuclear fuel assembly comprising a plurality of control rod guide assemblies. At least one of the control rod guide assemblies includes a guide tube having an axial dimension, the guide tube being supported by the plurality of grids and extending axially between the top nozzle and the bottom nozzle, the guide tube having an upper portion having a first radius and a lower portion having a second radius less than the first radius, and an external dashpot tube disposed around a portion of the lower portion in an area beginning at the bottom grid and extending toward the top nozzle.
	summary
	claims	1. A radiation-shielding glass, comprising a glass composition in % by mass of 10 to 35% SiO2, 55 to 80% PbO, 0 to 8% B2O3, 0 to 10% Al2O3, 0 to 10% SrO, 0 to 10% BaO, 0 to 10% Na2O, and 0 to 10% K2O, wherein:the glass composition further includes 200 ppm or less of Fe2O3, 50 ppm or less of Cr2O3, and 100 to 20,000 ppm of Sb2O3, and is substantially free of As2O3,the radiation-shielding glass has a total light transmission at a wavelength of 400 nm at a thickness of 10 mm of 50% or more, andthe radiation-shielding glass has a chromaticity for a C light source calculated from a total light transmission at a wavelength of 380 to 700 nm in a region surrounded by X and Y coordinates (X, Y)=(0.3101, 0.3160), (0.3250, 0.3160), (0.3250, 0.3400), and (0.3101, 0.3400). 2. A radiation-shielding glass, comprising a glass composition in % by mass of 10 to 35% SiO2, 55 to 80% PbO, 0 to 8% B2O3,0 to 10% Al2O3, 0 to 10% SrO, 0 to 10% BaO, 0 to 10% Na2O, and 0 to 10% K2O, wherein:the glass composition further includes 200 ppm or less of Fe2O3, 50 ppm or less of Cr2O3, and 100 to 20,000 ppm of Sb2O3, and is substantially free of As2O3,the radiation-shielding glass has a chromaticity for a C light source calculated from a total light transmission at a wavelength of 380 to 700 nm in a region surrounded by X and Y coordinates (X, Y)=(0.3101, 0.3160), (0.3250, 0.3160), (0.3250, 0.3400), and (0.3101, 0.3400), andthe radiation-shielding glass is used for a gamma-ray shielding material for a PET examination. 3. A radiation-shielding glass according to claim 1 or claim 2, wherein the glass composition further includes 0 to 20,000 ppm of Cl2. 4. A radiation-shielding glass according to claim 1 or claim 2, wherein the radiation-shielding glass has a liquidus viscosity of 103.5 dPas or more. 5. A radiation-shielding glass according to claim 1 or claim 2, wherein:the radiation-shielding glass is a plate-like body formed in a plate shape; andthe plate-like body has a plate thickness of 10 mm or more. 6. A radiation-shielding glass according to claim 1 or claim 2, wherein the radiation-shielding glass has a gamma-ray attenuation coefficient at a gamma-ray energy of 0.511 MeV of 0.5 cm−1. 7. A method of shielding a subject from gamma rays, comprising placing a gamma-ray shielding window or a gamma-ray shielding protection screen between the subject and the source of the gamma rays, wherein the gamma-ray shielding window or the gamma-ray shielding protection screen comprises the radiation-shielding glass according to claim 1 or claim 2. 8. The method of claim 7, wherein the source of the gamma rays is a medical use. 9. The method of claim 8, wherein the medical use is a PET examination. 10. A radiation-shielding glass according to claim 1 or claim 2, wherein:the radiation-shielding glass is a glass plate formed in a plate shape; andan effective dose build-up factor for the radiation based on a glass composition and a density of a glass plate to be formed is calculated before the formation of the glass plate, an effective dose transmission of the glass plate to be formed for the radiation is calculated by multiplying the effective dose build-up factor by a transmission when the radiation is perpendicularly incident on the glass plate to be formed, and a theoretical plate thickness value of the glass plate to be formed is determined based on the effective dose transmission, and an actual plate thickness is set to be equal to or higher than the theoretical plate thickness value. 11. A radiation-shielding glass according to claim 10, wherein the theoretical plate thickness value is obtained by further making a comparison between an effective dose transmission of lead obtained based on an effective dose build-up factor of lead with respect to the radiation and the effective dose transmission of the glass plate to be formed. 12. A radiation-shielding glass according to claim 10, wherein the theoretical plate thickness value is set to a value where the effective dose transmission of the glass plate to be formed is 60% or less with respect to a gamma ray at 0.511 MeV. 13. A radiation-shielding glass according to claim 10, wherein the effective dose build-up factor of the glass plate to be formed is calculated by Monte Carlo method. 14. A radiation-shielding glass according to claim 10, wherein when the theoretical plate thickness value is defined as t, the plate thickness is actually in the range of t or more and 1.3 t or less. 15. A radiation-shielding glass according to claim 10, wherein the radiation-shielding glass hasa density of 4.00 g/cm3 or more, and an effective dose transmission of 60% or less with respect to a gamma ray at 0.511 MeV. 16. A radiation-shielding glass according to claim 10, wherein the radiation-shielding glass hasa size of 800 mm×1,000 mm or more. 17. A radiation-shielding glass article including the radiation-shielding glass according to claim 1 or claim 2, comprising a single plate glass formed of the radiation-shielding glass. 18. A method of manufacturing the radiation-shielding glass according to claim 1 or claim 2, comprising melting a glass material in a melting furnace to obtain a molten glass,wherein a melting temperature of the molten glass is 1,400° C. or less. 19. A method of manufacturing the radiation-shielding glass according to claim 1 or claim 2, comprising the steps of:melting a glass material in a melting furnace to obtain a molten glass; andforming the molten glass into a plate glass,wherein the plate glass is formed with a roll out method. 20. A method of manufacturing radiation-shielding glass according to claim 18, further comprising a step of setting a theoretical plate thickness value, including:calculating an effective dose build-up factor for the radiation based on a glass composition and a density of a glass plate to be formed before a step of forming a glass plate from a molten glass;calculating an effective dose transmission of the glass plate to be formed for the radiation by multiplying the effective dose build-up factor by a transmission when the radiation is perpendicularly incident on the glass plate to be formed; andsetting the theoretical plate thickness value of the glass to be formed based on the effective dose transmission. 21. A method of manufacturing the radiation-shielding glass for medical uses according to claim 20, wherein in the step of setting the theoretical plate thickness value, the theoretical plate thickness value is set by making a comparison between an effective dose transmission of lead obtained based on an effective dose build-up factor of lead against the radiation and an effective dose transmission of the glass plate to be formed. 22. A method of manufacturing radiation-shielding glass according to claim 19, further comprising a step of setting a theoretical plate thickness value, including:calculating an effective dose build-up factor for the radiation based on a glass composition and a density of a glass plate to be formed before a step of forming a glass plate from a molten glass;calculating an effective dose transmission of the glass plate to be formed for the radiation by multiplying the effective dose build-up factor by a transmission when the radiation is perpendicularly incident on the glass plate to be formed; andsetting the theoretical plate thickness value of the glass to be formed based on the effective dose transmission. 23. A method of manufacturing radiation-shielding glass according to claim 22, further comprising a step of setting a theoretical plate thickness value, including:calculating an effective dose build-up factor for the radiation based on a glass composition and a density of a glass plate to be formed before a step of forming a glass plate from a molten glass;calculating an effective dose transmission of the glass plate to be formed for the radiation by multiplying the effective dose build-up factor by a transmission when the radiation is perpendicularly incident on the glass plate to be formed; andsetting the theoretical plate thickness value of the glass to be formed based on the effective dose transmission. 24. A method of using a radiation-shielding glass, comprising producing a gamma-ray shielding window for a PET examination or a gamma-ray shielding protection screen for a PET examination from the radiation-shielding glass having the properties as defined in claim 1, and arranging the window or screen between a patient to which a test drug has been administered and a tester in the PET examination.
	description	The embodiments of the present invention will be described below with reference to the accompanying drawings. (First Embodiment) The present invention is applied to, e.g., a radiation imaging system 100 as shown in FIG. 1. less than Arrangement of Radiation Imaging System 100 greater than As shown in FIG. 1, the radiation imaging system 100 has an arrangement including an imaging device 110 for acquiring an image signal of an object (patient) 102 to be examined, a control device 111 for controlling the entire system 100, a storage device 112 for storing various data such as a control program for control processing by the control device 111 and the image, a display device 113 for displaying the image or the like, an image processing device 114 for executing arbitrary image processing for the image signal of the patient 102, which is obtained by the imaging device 110, an imaging condition instruction device 115 for instructing various imaging conditions in the imaging device 110, an imaging button 116 for instructing the system 100 to start imaging operation, and a radiation generator 117 for generating a radiation (e.g., X-rays) from a radiation tube 101 to the patient 102. The devices or components are connected to each other through a system bus 120 to exchange data. The imaging device 110 is located at a position where the radiation generated from the radiation tube 101 of the radiation generator 117 can be received through the patient 102. The imaging device 110 comprises a chest stand 103, grid 104, phosphor 105, sensor (two-dimensional solid-state image sensing element) 106, signal reading section 107, and grid moving section 108. The chest stand 103, grid 104, phosphor 105, and sensor 106 are arranged in this order from the side of the radiation tube 101 of the radiation generator 117. less than Series of Operations of Radiation Imaging System 100 greater than Outlines of the imaging procedure and radiation image generation process in the radiation imaging system 100 will be described here. The user (e.g., radiation technician) positions the patient 102 to the chest stand 103 and selectively inputs appropriate imaging conditions (e.g., tube voltage, tube current, irradiation time, type of sensor 106, and type of radiation tube 101) using the imaging condition instruction device 115. In this embodiment, the imaging conditions are manually inputted by the user through the imaging condition instruction device 115. However, the present invention is not limited to this. For example, the imaging conditions may be inputted through a network (not shown) connected to the imaging device 110. Next, the user presses the imaging button 116 to request the control device 111 to start imaging operation. After receiving the imaging operation start request from the user, the control device 111 performs initialization necessary in the system 100 and prompts the radiation generator 117 to irradiate the person with radiation. In accordance with the irradiation instruction from the control device 111, the radiation generator 117 generates radiation from the radiation tube 101. The radiation generated from the radiation tube 101 passes through the patient 102 and reaches chest stand 103. The chest stand 103 is exposed by the radiation transmitted through the patient 102 with a transmitted radiation distribution in accordance with the structure in the patient 102. Since the chest stand 103 is sufficiently transparent to the radiation, the radiation transmitted through the chest stand 103 reaches the grid 104. The grid 104 removes scattering ray components in the radiation transmitted through the chest stand 103 and sends only effective radiation components to the phosphor 185. The phosphor 105 converts the radiation (effective radiation) from the grid 104 into visible light in accordance with the spectral sensitivity of the sensor 106. The sensor 106 receives the radiation from the phosphor 105, converts the radiation light into an electrical signal (image signal) by two-dimensional photoelectric conversion, and accumulates it. The signal reading section 107 reads out the image signal accumulated in the sensor 106 and stores the signal in the storage device 112 as a radiation image signal. The image processing device 114 performs appropriate image processing for the radiation image signal stored in the storage device 112. The display device 113 displays the radiation image signal after processing by the image processing device 114. less than Most Characteristic Operation and Arrangement of Radiation Imaging System 100 greater than FIG. 2 is a flow chart showing operation control processing executed by the control device 111 for the system 100. FIGS. 3A to 3F are timing charts showing the operation control timing. The processing shown in FIG. 2 corresponds to processing from the above-described imaging condition input by the user to image signal read from the sensor 106. Step S201: The control device 111 recognizes an irradiation time Texp, the type of sensor 106 used for imaging, and the type of radiation tube 101 on the basis of imaging conditions selectively input by the user through the imaging condition instruction device 115. In accordance with the recognized information, the control device 111 determines control until radiation irradiation and control after radiation irradiation by processing from step S202. Step S202: The control device 111 determines a sensor initialization time Tss in accordance with the type of sensor 106. The sensor initialization time Tss changes depending on the type of sensor 106. For example, when the sensor 106 requires predischarge of a dark current, the pre-read time is the sensor initialization time Tss. From this time, signal accumulation in the sensor 106 starts. Step S203: The control device 111 determines a grid initialization time Tgs and grid oscillation convergence time Tge from the irradiation time Texp. More specifically, to reduce stripe image formation on the object by the grid 104, for example, radiation must be transmitted through stripes of 10 or more cycles. However, the moving distance of the grid 104 is limited. Hence, the moving speed of the grid 104 must be optimized in accordance with the irradiation time Texp. In addition, since the grid 104 generally has a focal point, the irradiation central position of radiation and the central position of the grid 104 must be aligned to obtain an image with a satisfactory quality. Hence, a time required until the optimum moving speed (target moving speed) of the grid 104 is obtained, and the position of the grid 104 reaches the irradiation central position (target position) of radiation corresponds to the grid initialization time Tgs. In this embodiment, the grid initialization times Tgs until the target moving speed and position of the grid 104 are obtained and the grid oscillation convergence times Tge required to converge device oscillation caused by movement are obtained as a table by experiments in correspondence with, e.g., various patterns of irradiation time Texp and moving speed of the grid 104 and stored in the storage device 112 in advance. The grid initialization time Tgs and grid oscillation convergence time Tge corresponding to the actually obtained irradiation time Texp are determined from the table information in the storage device 112. Step S204: The control device 111 determines a pre-irradiation delay time Txs and post-irradiation delay time Txe on the basis of the type of radiation tube 101. The pre-irradiation delay time Txs is a time after the radiation generator 117 is instructed to permit radiation irradiation until the radiation generator 117 actually starts radiation irradiation, and is determined by the type of radiation generator 117 or radiation tube 101. In this embodiment, the pre-irradiation delay times Txs corresponding to, e.g., various types of radiation generator 117 or radiation tube 101 are prepared as a table in advance, and a corresponding pre-irradiation delay time Txs is determined from the table information. The post-irradiation delay time Txe is a delay time after the elapse of irradiation time Texp until the radiation generator 117 actually ends the radiation irradiation. The post-irradiation delay time Txe is also determined in accordance with the same procedure as that for the pre-irradiation delay time Txs. Step S205: The control device 111 determines an irradiation delay time T1. The irradiation delay time T1 is a delay time after an imaging request is input by the user through the imaging button 116 until the radiation generator 117 actually starts radiation irradiation. Of the sensor initialization time Tss determined in step S202, the grid initialization time Tgs determined in step S203, and the pre-irradiation delay time Txs determined in step S204, the longest time is determined as the irradiation delay time T1. Step S206: The control device 111 determines a time table before irradiation. This time table is determined from the sensor initialization time Tss determined in step S202, the grid initialization time Tgs determined in step S203, and the pre-irradiation delay time Txs determined in step S204. More specifically, the control sequence and times (timings) of initialization of the sensor 106, start of drive of the grid 104, and radiation irradiation instruction (irradiation permission) to the radiation generator 117 after the imaging request input by the user through the imaging button 116 is recognized are determined by subtracting each delay time from the irradiation delay time T1 determined in step S205. The initialization timing of the sensor 106 is determined as xe2x80x9cT1xe2x88x92Tssxe2x80x9d. The drive start timing of the grid 104 is determined as xe2x80x9cT1xe2x88x92Tgsxe2x80x9d. The radiation irradiation instruction (irradiation permission) timing for the radiation generator 117 is determined as xe2x80x9cT1xe2x88x92Txsxe2x80x9d. Step S207: After control before radiation irradiation is determined in the above-described way, the control device 111 determines whether an imaging request is input by the user through the imaging button 116 and stands by until an imaging request is received. Step S208: Upon recognizing that an imaging request is input by the user through the imaging button 116, the control device 111 executes operation control according to the time table determined in step S206. Initialization of the sensor 106 is started after the elapse of xe2x80x9cT1xe2x88x92Tssxe2x80x9d, drive of the grid 104 is started after the elapse of xe2x80x9cT1xe2x88x92Tgsxe2x80x9d, and irradiation permission is executed after the elapse of xe2x80x9cT1xe2x88x92Txsxe2x80x9d. Step S209: The control device 111 stands by until the total time (T1+Texp+Txe) of the irradiation time (actual exposure time) Texp determined in step S201, the post-irradiation delay time Txe determined in step S204, and the irradiation delay time T1 determined in step S205 elapses. Step S210: When recognizing that the time (T1+Texp+Txe) has elapsed, the control device 111 stops driving the grid 104 through the grid moving section 108. Step S211: The control device 111 stands by until the grid oscillation convergence time Tge determined in step S203 elapses. Step S212: When recognizing that the grid oscillation convergence time Tge has elapsed, the control device 111 causes the signal reading section 107 to start reading out the signal accumulated in the sensor 106. In the operation control for the radiation imaging system 100 shown in the flow chart of FIG. 2, especially, since the operation stands by for the post-irradiation delay time Txe after the elapse of irradiation time Texp, stripe image formation on the object by the grid 104 can be prevented. In addition, since drive of the grid 104 is stopped, the influence of electromagnetic noise generated from the grid moving section 108 can be prevented. Furthermore, since the operation stands by for the grid oscillation convergence time Tge after the stop of drive of the grid 104, the influence of device oscillation can be prevented. Hence, after the imaging request from the user is recognized, the control device 111 controls the operation of the system 100 in accordance with the flow chart in FIG. 2, thereby acquiring a satisfactory image. The above operation control for the radiation imaging system 100 will be described below in more detail with reference to the timing charts shown in FIGS. 3A to 3F. The timing charts of FIGS. 3A to 3F explain timings after the imaging button 116 is pressed. In accordance with the imaging conditions input by the user, for example, Irradiation time Texp=100 ms Sensor initialization time Tss=200 ms Grid initialization time Tgs=300 ms Pre-irradiation delay time Txs=100 ms Grid oscillation convergence time Tge=300 ms Post-irradiation delay time Txe=100 ms are determined. In this case, the irradiation delay time T1 is the longest time of the sensor initialization time Tss, grid initialization time Tgs, and pre-irradiation delay time Txs and is determined by T1=max(Tss, Tgs, Txs)=Tgs=300 ms. Operation control until radiation irradiation is determined from these initial conditions. Next, control timings for sensor initialization, start of grid movement, and irradiation permission instruction after recognition of the imaging request are determined by subtracting a corresponding time required for operation from the irradiation delay time T1. Sensor initialization timing: T1xe2x88x92Tss 100 ms Grid movement start timing: T1xe2x88x92Tgs 0 ms Irradiation enable signal transmission timing: T1xe2x88x92Txsxe2x88x92200 ms Control timings after radiation irradiation are so determined that movement control for the grid 104 is stopped after the elapse of actual irradiation time obtained by adding the irradiation time Texp and post-irradiation delay time Txe to the irradiation delay T1, and the signal read from the sensor 106 is started after the elapse of grid oscillation convergence time Tge. That is, the grid control stop timing and signal read start timing are determined by Grid control stop timing: T1+Texp+Txe=500 ms Signal read start timing: T1+Texp+Txe+Tge=800 ms After the control timings are determined, an imaging request (FIG. 3A) input by the user by pressing the imaging button 116 is waited upon. When an imaging request is recognized, operation control for the radiation imaging system 100 is started on the basis of the determined control timings. First, movement (motion) of the grid 104 is started, as shown in FIG. 3B. The moving speed of the grid 104 acceleratingly increases and reaches an irradiation enable state after the elapse of 300 ms (grid initialization time Tgs=300 ms), as shown in FIG. 3C. Next, as shown in FIG. 3F, after the elapse of 100 ms (sensor initialization timing: T1xe2x88x92Tss=100 ms) from imaging request recognition, initialization of the sensor 106 is started. After the elapse of 200 ms (sensor initialization time Tss=200 ms), initialization of the sensor 106 is ended. As shown in FIG. 3D, after the elapse of 200 ms (irradiation enable signal transmission timing: T1xe2x88x92Txs=200 ms) from imaging request recognition, the radiation generator 117 is instructed to start irradiation. The radiation generator 117 starts actual irradiation after the elapse of 100 ms (preirradiation delay time Txs=100 ms), as shown in FIG. 3E. The end timing of sensor initialization (end timing of the sensor initialization time Tss), the end timing of grid movement (end timing of the grid initialization time Tgs), and the end timing of irradiation enable signal transmission (end timing of the pre-irradiation delay time Txs) match the end timing of the irradiation delay time T1 from the imaging request to actual irradiation. After the elapse of 500 ms (grid control stop timing: T1+Texp+Txe=500 ms) from imaging request recognition, actual irradiation by the radiation generator 117 is ended. At this time, movement control for the grid 104 is stopped, as shown in FIG. 3B, and the moving speed of the grid 104 gradually decreases. Along with this deceleration, the oscillation of the imaging device 110, that is generated by moving the grid 104, starts converging. After that, as shown in FIG. 3F, after the elapse of 800 ms (signal read start timing: T1+Texp+Txe+Tge=800 ms) from imaging request recognition, the signal reading section 107 is instructed to end signal accumulation in the sensor 106 and start reading the signal. At this time, the oscillation of the imaging device 110 has become so small that it does not affect the image quality. As a result, a satisfactory image can be obtained. (Second Embodiment) The present invention is applied to, e.g., a radiation imaging system 300 as shown in FIG. 4. This radiation imaging system 300 has the same arrangement as that of the radiation imaging system 100 shown in FIG. 1 except that a radiation detector 302 for detecting a radiation irradiation state and an oscillation measurement device 301 for measuring the oscillation state of a grid 104 are prepared in an imaging device 110. The same reference numerals as in the radiation imaging system 100 shown in FIG. 1 denote the same parts in the radiation imaging system 300 shown in FIG. 4, and a detailed description thereof will be omitted. Only parts different from the radiation imaging system 100 in FIG. 1 will be described in detail. FIG. 5 is a flow chart showing operation control processing executed by a control device 111 of this embodiment for the system 300. FIGS. 6A to 6H are timing charts showing the operation control timing. The same step numbers as in the flow chart of FIG. 2 denote the same processing steps in the flow chart of FIG. 5, and a detailed description thereof will be omitted. Step S201: The control device 111 recognizes an irradiation time Texp, the type of sensor 106 used for imaging, and the type of radiation tube 101 on the basis of imaging conditions selectively input by the user through an imaging condition instruction device 115. In accordance with the recognized information, the control device 111 determines control until radiation irradiation and control after radiation irradiation by processing from step S202. Step S202: The control device 111 determines a sensor initialization time Tss in accordance with the type of sensor 106. Step S203xe2x80x2: The control device 111 determines a grid initialization time Tgs (time until the grid 104 reaches the target moving speed and position) from the irradiation time Texp. Step S204xe2x80x2: The control device 111 determines a pre-irradiation delay time Txs (time after radiation irradiation permission is instructed to a radiation generator 117 until the radiation generator 117 actually starts radiation irradiation) on the basis of the type of radiation tube 101. Step S205: The control device 111 determines an irradiation delay time T1 (the longest time of the sensor initialization time Tss, grid initialization time Tgs, and pre-irradiation delay time Txs). Step S206: The control device 111 determines, as a time table before irradiation, the initialization timing of the sensor 106 as xe2x80x9cT1xe2x88x92Tssxe2x80x9d, the drive start timing of the grid 104 as xe2x80x9cT1xe2x88x92Tgsxe2x80x9d, and the radiation irradiation instruction (irradiation permission) timing for the radiation generator 117 as xe2x80x9cT1xe2x88x92Txsxe2x80x9d. Step S207: After control before radiation irradiation is determined in the above-described way, the control device 111 determines whether an imaging request is input by the user through an imaging button 116 and stands by until an imaging request is received. Step S208: Upon recognizing that an imaging request is input by the user through the imaging button 116, the control device 111 executes operation control according to the time table determined in step S206. Initialization of the sensor 106 is started after the elapse of xe2x80x9cT1xe2x88x92Tssxe2x80x9d. Drive of the grid 104 is started after the elapse of xe2x80x9cT1xe2x88x92Tgsxe2x80x9d. Irradiation permission is executed after the elapse of xe2x80x9cT1xe2x88x92Txsxe2x80x9d. Step S209xe2x80x2: The control device 111 determines on the basis of a detection signal output from the radiation detector 302 whether radiation irradiation by the radiation generator 117 is ended. Step S210: Upon recognizing that radiation irradiation by the radiation generator 117 is ended, the control device 111 stops driving the grid 104 through a grid moving section 108. Step S211xe2x80x2: The control device 111 determines on the basis of a measurement result from the oscillation measurement device 301 whether the oscillation of the grid 104 has converged. Step S212: When recognizing that the oscillation of the grid 104 has converged, the control device 111 causes a signal reading section 107 to start reading out the signal accumulated in the sensor 106. In the operation control for the radiation imaging system 300 shown in the flow chart of FIG. 5, especially when the end of radiation irradiation is recognized in accordance with the detection result from the radiation detector 302, drive of the grid 104 is stopped. For this reason, the influence of electromagnetic noise generated from the grid moving section 108 can be prevented. Furthermore, since the operation stands until it is determined on the basis of the measurement result from the oscillation measurement device 301 that the oscillation of the grid 104 has converged after the stop of drive of the grid 104, the influence of device oscillation can be prevented. Hence, after the imaging request from the user is recognized, the control device 111 controls the operation of the system 300 in accordance with the flow chart in FIG. 5, thereby acquiring a satisfactory image. The above operation control for the radiation imaging system 300 will be described below in more detail with reference to the timing charts shown in FIGS. 6A to 6H. The timing charts of FIGS. 6A to 6H explain timings after the imaging button 116 is pressed. In accordance with the imaging conditions input by the user, for example, Irradiation time Texp=100 ms Sensor initialization time Tss=200 ms Grid initialization time Tgs=300 ms Pre-irradiation delay time Txs=100 ms are determined. In this case, the irradiation delay time T1 is the longest time of the sensor initialization time Tss, grid initialization time Tgs, and pre-irradiation delay time Txs and is determined by T1=max(Tss, Tgs, Txs)=Tgs=300 ms. Operation control until radiation irradiation is determined from these initial conditions. Next, control timings for sensor initialization, start of grid movement, and irradiation permission instruction after recognition of the imaging request are determined by subtracting a corresponding time required for operation from the irradiation delay time T1. Sensor initialization timing: T1 Tss=100 ms Grid movement start timing: T1 Tgs=0 ms Irradiation enable signal transmission timing: T1xe2x88x92Txs=200 ms After the control timings are determined, an imaging request (FIG. 6A) input by the user by pressing the imaging button 116 is waited upon. When an imaging request is recognized, operation control for the radiation imaging system 300 is started on the basis of the determined control timings. First, movement (motion) of the grid 104 is started, as shown in FIG. 6B. Simultaneously, the oscillation detection signal representing that the grid 104 is in a moving state is set at High level, as shown in FIG. 6G. The moving speed of the grid 104 acceleratingly increases and reaches an irradiation enable state after the elapse of 300 ms (grid initialization time Tgs=300 ms), as shown in FIG. 6C. Next, as shown in FIG. 6H, after the elapse of 100 ms (sensor initialization timing: T1xe2x88x92Tss=100 ms) from imaging request recognition, initialization of the sensor 106 is started. After the elapse of 200 ms (sensor initialization time Tss=200 ms), initialization of the sensor 106 is ended. As shown in FIG. 6D, after the elapse of 200 ms (irradiation enable signal transmission timing: T1xe2x88x92Txs=200 ms) from imaging request recognition, the radiation generator 117 is instructed to start irradiation. The radiation generator 117 starts actual irradiation after the elapse of 100 ms (pre-irradiation delay time Txs=100 ms), as shown in FIG. 6E. Simultaneously, the radiation detection signal representing radiation irradiation is set at High level, as shown in FIG. 6F. When radiation irradiation is ended, and the output from the radiation detector 302 becomes smaller than a predetermined threshold value, it is determined that irradiation is ended. As shown in FIG. 6F, the radiation detection signal is set at Low level. Along with this processing, movement control for the grid 104 is stopped, as shown in FIG. 6B. The moving speed of the grid 104 gradually decreases. The oscillation state of the grid 104 at this time is observed by the oscillation measurement device 301. When the oscillation of the imaging device 110, that is generated by moving the grid 104, starts converging, and it is recognized that the output from the oscillation measurement device 301 becomes smaller than a predetermined oscillation amount, the oscillation detection signal is set at Low level, as shown in FIG. 6G. As shown in FIG. 6F, the signal reading section 107 is instructed to end signal accumulation in the sensor 106 and start reading the signal. At this time, the oscillation of the imaging device 110 has become so small that it does not affect the image quality. As a result, a satisfactory image can be obtained. The object of the present invention is achieved even by supplying a storage medium which stores software program codes for implementing the functions of the first and second embodiments in a system or apparatus and causing the computer (or a CPU or MPU) of the system or apparatus to read out and execute the program codes stored in the storage medium. In this case, the program codes read out from the storage medium implement the functions of the first and second embodiments by themselves, and the storage medium which stores the program codes constitutes the present invention. As a storage medium for supplying the program codes, for example, a ROM, a floppy disk, hard disk, optical disk, magnetooptical disk, CD-ROM, CD-R, magnetic tape, nonvolatile memory card or the like can be used. The functions of the first and second embodiments are implemented not only when the readout program codes are executed by the computer, but also when the operating system (OS) running on the computer performs part or all of actual processing on the basis of the instructions of the program codes. The functions of the first and second embodiments are also implemented when the program codes read out from the storage medium are written in the memory of a function expansion board inserted into the computer or a function expansion unit connected to the computer. The CPU of the function expansion board or function expansion unit performs part or all of actual processing on the basis of the instructions of the program codes. As has been described above, in the above embodiments, the timing when the irradiation means is permitted to perform irradiation is determined from the initialization time of the image sensing means (e.g., two-dimensional solid-state image sensing element) and the irradiation delay time (delay time after irradiation execution instruction, i.e., irradiation permission is issued until actual irradiation is performed) of the irradiation means (e.g., radiation generation means). Therefore, imaging operation control for an imaging request and initialization of the image sensing element can be parallelly executed. Accordingly, the time delay from the imaging request to actual irradiation can be shortened. Additionally, the timing when the irradiation means is permitted to perform irradiation is determined from the initialization time of the image sensing means and the initialization time of grid movement (delay time until the grid moves to an appropriate target position), or the initialization time of the image sensing means, the irradiation delay time of the irradiation means, and the initialization time of grid movement. Therefore, imaging operation control for an imaging request and initialization of the image sensing element and/or grid movement can be parallelly executed. Accordingly, the time delay from the imaging request to actual irradiation can be shortened. Furthermore, since grid movement such as the grid position or speed can be controlled in consideration of the irradiation delay time corresponding to the irradiation means used for imaging, a satisfactory image without any grid stripe image formation on the object can be obtained. Hence, according to the above embodiments, a satisfactory image can be obtained at a desired imaging timing. For example, when the present invention is applied to radiation imaging, a satisfactory radiation image without any grid stripe image formation on the object can be provided, and any diagnostic error in image diagnosis can be reliably prevented. The present invention is not limited to the above embodiments and various changes and modifications can be made within the spirit and scope of the present invention. Therefore, to apprise the public of the scope of the present invention, the following claims are made.
	description	This application claims benefit of Serial No. 201410767544.0, filed 11 Dec. 2014 in China and which application is incorporated herein by reference. A claim of priority is made to the above disclosed application. Field of the Invention Embodiments of the present disclosure relate to the field of X or Gamma ray security inspection, and particularly, to an X or Gamma ray inspection system for inspecting an object such as a container or vehicle, and an alignment system and an alignment method for the inspection system. Description of the Related Art Term “three points on one line” relates to a target spot of an accelerator, a central line of a detector tip, a central line of a collimator which are coplanar, and adjustments of “three points on one line” are intended to ensure that the target spot of the accelerator, the central line of the detector tip, and the central line of the collimator (sometimes including a central line of a calibrating device and the like) are located in one reference plane, as shown in FIG. 1. In an existing measurement method, alignment of the target spot of the accelerator, the central line of the detector tip, and the central line of the collimator is manually measured by using a laser theodolite. A vertical line of a reticle of the theodolite is arranged to coincide with central lines of detectors on upper and lower ends of a detector vertical arm, and to align with a center of the target spot as far as possible. This method is implemented through the human eye, and thus is insufficient in objectivity and accuracy, that is, is easily and greatly affected by placement and debugging of instruments and the visual sense of the measurer. Further, a detector arm mount is generally used in many existing movable inspection systems, and needs to be unfolded quickly for operation after these movable inspection systems reach a new inspection site. However, the detector arm or mount, as a mechanical structure, needs to be further adjusted so that the ray source, the collimator and the detector are located within one plane. Thus, there is a need to alignment system and method enabling accurate, quick and reliable alignment. In view of the above, an object of the present disclosure is aimed to solve at least one of the above problems so as to achieve quick alignment of the ray beam and the detector module of the inspection system. According to a first aspect of the present disclosure, there is provided an alignment system for a container or vehicle inspection system, comprising a measuring module, which is a sensor array consisted of a plurality of sensors each configured to measure ray intensity; a row of sensors of the measuring module are arranged on a longitudinal central line of a detector module of the container or vehicle inspection system, so that it is determined that rays are aligned with the detector module when a ray intensity value measured by the row of sensors of the measuring module arranged on the longitudinal central line of the detector module ray intensity value is a maximum value of a ray intensity value curve. According to a second aspect of the present disclosure, there is provided an alignment system for a container or vehicle inspection system, comprising a measuring module, which is a sensor row consisted of a plurality of sensors each configured to measure ray intensity; one sensor of the measuring module is arranged on a longitudinal central line of a detector module of the container or vehicle inspection system, so that it is determined that rays are aligned with the detector module when a ray intensity value measured by the one sensor of the measuring module arranged on the longitudinal central line of the detector module is a maximum value of a ray intensity value curve. According to a third aspect of the present disclosure, there is provided an inspection system for a container or a vehicle, comprising an ray source, a collimator, a detector arm and a detector module mounted on the detector arm, the ray source, the collimator and the detector module being arranged to form an inspection passage, rays emitted from the ray source passing through collimator, irradiating onto an inspected object and collected by the detector module so as to complete inspection, wherein the inspection system further comprises the above alignment system. According to a fourth aspect of the present disclosure, there is provided an alignment method for an inspection system for a container or a vehicle, comprising: arranging the above alignment system on a longitudinal central line of the detector module located on a detector arm of the container or vehicle inspection system; arranging a ray source, a collimator and the detector module of the container or vehicle inspection system to form an inspection passage, the ray source emitting rays, which pass through the collimator and are received by the measuring module of the alignment system and the detector module; determining a position of a main ray beam based on ray intensity maximum values fed back from respective sensors of the measuring module; calculating a difference between a position on the detector module to which the main ray beam irradiates and the position of the longitudinal central line of the detector module; and adjusting the position of the ray source, the collimator or the detector module so that position on the detector module to which the main ray beam irradiates coincides with the position of the longitudinal central line of the detector module. Exemplary embodiments of the present invention will be described hereinafter in detail with reference to the attached drawings, wherein the like reference numbers refer to the like elements. In the following detailed description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that one or more embodiments may be practiced without these specific details. In other instances, well-known structures and devices are schematically shown in order to simplify the drawings. In an embodiment of the present disclosure, a container or vehicle inspection system, in which X or Gamma rays are applied, comprises a ray source 1, a collimator 2 and a detector module 3 mounted on a detector arm. The ray source 1 may be an X-ray accelerator or a Gamma ray accelerator. In order to obtain better collimated rays, the collimator 2 may be arranged at a ray outlet of the accelerator. Those skilled in the art will understand that desired rays may be obtained by using other devices, for example, a device for directly emitting collimated rays. The detector module 3 is provided on the detector arm 4. The detector arm 4 comprises a detector transverse arm 41 and a detector vertical arm 42, and when the detector arm 4 is unfolded, the detectors 3 on the detector transverse arm 41 and the detector vertical arm 42 receive a ray beam collimated by the collimator 2 and transmitted through an inspected object, thereby achieving inspection. That is, in use, the ray source 1, the collimator 2 and the detector module 3 forms an inspection passage, as shown in FIG. 2. The container or vehicle inspection system, in which X or Gamma rays are applied, further comprises an alignment system configured to align the ray source 1, the collimator 2 and the detector module 3. The alignment system comprises a measuring module 5. The measuring module 5 is arranged on the detector module 3. In one embodiment, the measuring module 5 is arranged on the arm or mount 4 of the detector module 3. The measuring module 5 is arranged to receive rays emitted from the ray source 1. As shown in FIG. 3, the measuring module 5 extends in a transverse direction, and the detector module 3 extends in a longitudinal direction. In an embodiment of the present disclosure, in order to determine the position of the detector module 3, the measuring module 5 is located at the position of the detector module 3 of the inspection system, so that the orientation of the collimator 2, that is, the position of a point of fall of the ray, is measured by the measuring module 5, and according to the measurement, the collimator 2 is adjusted to face towards the detector module 3. In this embodiment, the measuring module 5 is arranged on the detector arm 4 provided with the detector module 3, and it is ensured that a central line of the detector module 3 in a transverse direction or a central line of the detector arm 4 in the transverse direction corresponds to a certain known portion of the measuring module 5, for example, to a middle point of the measuring module 5. Herein, the central line of the detector module 3 is the same as the central line of the detector arm or mount 4, that is, the detectors are arranged in a vertical direction, and the detector arm 4 is divided into two equal halves by the central line extending in the vertical direction. In an embodiment of the present disclosure, the measuring module 5 is provided on the detector arm 4, as shown in FIG. 2. The measuring module 5 is consisted of a plurality of detector crystals 6, which have sizes smaller than those of detector crystals 6 of the imaging detector module 3 of the inspection system, or are small-sized detectors when compared to the detector crystals 6 of the imaging detector module 3 of the inspection system. Preferably, as shown in FIG. 3a, the width of each small-sized detector crystal 6 of the measuring module 5 may be 1/n of the measuring module 5, where n is an integer and may be selected as required. In other words, the measuring module 5 may be consisted of several small-sized detector crystals 6, which are arranged side by side to form a slender or elongate block body 6. The total width of the measuring module 5 is larger than the width of the detector module 3 of the system, as shown in FIG. 4. The length direction of the measuring module 5 extends in the transverse direction of the detector module 3. The measuring module 5 may be mechanically positioned on the detector module 3, and the elongate measuring module 5 may be arranged such that its middle point is located on the central line of the detector arm 4. The length extending direction of the elongate measuring module 5 is perpendicular to the length extending direction of the detector arm 4. As such, a specific position of a center of a beam may be finely and quantificationally measured. Data measured by each measuring module 5 may be transmitted to a computer for analysis. In an embodiment of the present disclosure, the total width of the measuring module 5 is four to five times of the width of the detector module 3 of the system. For example, the width of the detector module 3 is 10 mm, the width of each small-sized detector crystal 6 of the measuring module 5 is 1.5 mm, and the measuring module 5 is consisted of thirty two small-sized detector crystals 6 and thus its width is 32×1.5=48 mm, as shown in FIG. 4. When the ray source 1 emits rays, a ray beam irradiates the measuring module 5 after being collimated by the collimator 2, the collimated rays are incident onto the plurality of detector crystals 6 of the measuring module 5, where a ray intensity received by a detector crystal 6 onto which the rays are being incident is the greatest, and energy of rays received by the detector crystals 6 adjacent to the detector crystal 6 onto which the rays are being incident is gradually reduced, that is, the ray intensities measured by the detector crystals 6 reduce as distances at which they are located away from the detector crystal 6 onto which the rays are being incident increase. FIG. 5 is a schematic diagram showing a curve formed by intensity values respectively measured by the thirty two detector crystals 6 when the center of the measuring module 5 is located on the central line of the detector arm 4. As can be seen from FIG. 5, since the collimated rays are aligned with the central line of the detector arm 4, the ray intensity detected by the detector crystal 6 at the middle of the measuring module 5 is the strongest, that is, the highest point in the curve of the figure (the Y axis in the Figure shows normalized values of the measured ray intensities). Ray intensities measured by the detector crystals 6 located away from the middle point of the measuring module 5 reduce as distances between these detector crystals 6 and the middle point. According to embodiments of the present disclosure, it is advantageous to determine alignment by using the curve shown in FIG. 5, for example, the operator may directly determine the position of a peak of the rays according to positions on the curve and thus directly determine a direction to which an adjustment is to be made. When the collimator 2 is not aligned with the middle point of the measuring module 5, that is, not aligned with the central line of the detector arm 4, the highest point on the curve shown in FIG. 5 will deviate from the middle point of the measuring module 5 (because the detector crystals 6 are fixed in position, the position of the middle detector crystal 6 is known, and measured ray intensity value fall on the Y axis). FIG. 6 and FIG. 7 are schematic diagrams respectively showing intensity curves measured when the collimator 2 deviates from the central line of the detector arm 4. In the present disclosure, deviation of the peak on the intensity curve from the Y axis may be used to indicate deviation of the collimator 2 or X-ray (or misalignment of the detector module; it will be understood by those skilled in the art that the misalignment is relative, that is, relates to relative positions between the combination of the X-rays and the collimator on an emitting side and the detector module on a receiving side), and the intensity peak can be adjusted onto the Y axis by adjusting the direction of the collimator 2 to face or align with the central line of the detector arm 4. With such a curve analogous to a parabola, the operator can directly judge the deviation and approximately estimate deviation amount through the deviation of the peak of the curve from the Y axis, thereby the alignment operation is easy. Thus, with the technique solutions provided according to embodiments of the present disclosure, uncertainty and randomicity of manual operations and adverse effects on subsequent inspection due to the randomicity can be avoided, and the alignment method is simple and explicit, adjustment is direct and quick, so that it is convenient for the operator to quickly complete preparation work before inspection. When the operator observes that the peak of the curve is on the right side of the Y axis, the detector module may be adjusted rightward. If the mount on which the detector module is provided is fixed, the X-rays and collimator are adjusted so that the ray beam or ray beams move leftward. In practice operation, the operator observes the curve to make a direct judgement without trying to find out adjustment direction, so that the preparation work before inspection is easy and quick. An adjustment device may be provided to adjust the orientation of the collimator 2. For example, a motor and a pivoting device may be provided, and the motor drives the pivoting device to pivot the collimator 2 so as to adjust the orientation of the collimator 2. Thus, automated adjustment may be achieved. According to an embodiment of the present disclosure, a method of aligning an accelerator and a detector by using an X or Gamma ray container or vehicle inspection system comprises steps of: 1) emitting rays by the accelerator; 2) measuring an ray intensity distribution by using the measuring module 5; 3) determining relative positions of the ray source 1, the collimator 2 and the arm 4, and making an adjustment; 4) repeating the steps 2, 3, until the ray beam collimated by the collimator 2 is aligned with the detector module 3. Specifically, for example, when a curve shown in FIG. 6 is displayed, the operator may adjust the collimator 2 rightward so that the intensity peak of the curve shown in FIG. 6 is moved to the Y axis. When a curve shown in FIG. 9 is displayed, the operator may adjust the collimator 2 leftward so that the intensity peak of the curve shown in FIG. 6 is moved to the Y axis. When the target spot of the accelerator, the central line of the detector tip and the central line of the collimator 2 are completely aligned with each other, signal intensities of X or Gamma rays received by respective detector crystals 6 of each measuring module 5 would be those shown in FIG. 5, in order words, the center of the ray beam may impinge the middlemost portion of the measuring module 5, that is, the tip central line of each detector module 3. According to the ray intensity distribution measured by respective detector modules 3 on the arm or mount 4, relative position relationship between the ray source 1, the collimator 2 and the arm or mount 4 may be determined, and position offset and angle deflection may be calculated to correct the system, so that the intensity distribution measured by all detector modules 3 is a parabola-like curve, as shown in FIG. 5. In another embodiment according to the present disclosure, a certain detector crystal 6 of the measuring module 5 is located on the central line of the detector module 3. Since it is known that the detector crystal 6 is located on the central line, it only needs to adjust the orientation of the collimator 2 so that the detected ray intensity maximum value is positioned at the position of the known detector crystal 6, thereby it can be determined that the collimator 2 is aligned with the central line of the detector module 3. That is, in this embodiment, the center of the measuring module 5 is not located on the central line of the detector module 3. In a further embodiment according to the present disclosure, the measuring module 5 is integrated into a whole. The measuring module 5 is an elongate measuring module 5, which may be an array consisted of a set of sensors each located at a defined and known position. Thus, the intensity of the ray beam received by each sensor is known. That is, the intensity of the ray beam received by each position is known. Accordingly, the orientation of the collimator 2 may be determined by viewing the position of the peak in the ray beam intensities. Similar to the above embodiments, the orientation of the collimator 2 may be adjusted so that the ray beam emitted from the collimator 2 faces toward a desired position, for example, toward the central line of the detector module 3. In a further embodiment according to the present disclosure, as shown in FIG. 3b, an alignment system for a container or vehicle inspection system comprises a measuring module 5, which is a sensor array consisted of a plurality of sensors each configured to measure ray intensity. A row of sensors of the measuring module are arranged on a longitudinal central line of a detector module of the container or vehicle inspection system. It is determined that rays are aligned with the detector module when a ray intensity value measured by the row of sensors (or a number of rows of small-sized sensors if the small-sized sensor of the measuring module has a volume much smaller than that of the detector module) of the measuring module arranged on the longitudinal central line of the detector module ray intensity value is a maximum value of a ray intensity value curve. It is known for those skilled in the art that the detector crystal 6 may has a certain volume, and the measuring module 5 is substantially transversely arranged along the detector arm 4, thus the technique solutions of the present disclosure are possible when an angle between the measuring module 5 and the detector arm 4 is in a certain range around 90 degrees. According to an embodiment of the present disclosure, there is provided an alignment method for aligning a container or vehicle inspection system. The inspection system comprises a ray source 1, a collimator 2 and a detector module 3 mounted on a detector arm 4, the ray source 1, the collimator 2 and the detector module 3 being arranged to form an inspection passage, rays emitted from the ray source 1 passing through collimator 2, irradiating onto an inspected object and collected by the detector module 3 so as to complete inspection. The alignment method comprises providing a measuring module 5, the measuring module 5 being arranged to receive rays emitted from the ray source 1 and collimated by the collimator 2. The alignment method further comprises determining a position of a main ray beam based on ray intensity peak values measured by the measuring module 5. It is determined that the main ray beam emitted from the ray source 1 and passing through the collimator 2 has be aligned with the detector module 3 when measurement from the measuring module 5 shows that the ray beam detected at the longitudinal central line of the detector module 3 has the largest intensity (that is, is the main ray beam). It will be appreciated by those skilled in the art that the ray source mentioned in the present disclosure may be other ray sources than the X-ray and Gamma ray sources. The ray beam described in the present disclosure may be rays in any form for irradiation, for example, may be a pen shaped beam, a fan ray beam or any other desired ray forms. Although several exemplary embodiments have been shown and described, it would be appreciated by those skilled in the art that various changes or modifications may be made in these embodiments without departing from the principle and spirit of the disclosure, the scope of which is defined in the claims and their equivalents.
	claims	1. A method for producing ground state 229Th, comprising the steps of:providing a target material comprising 226Ra,bombarding said target material with helium nuclei from a helium nuclei source to form ground state 229Th, andcontrolling said helium nuclei source to produce said helium nuclei with an incident energy between 8 and 20 MeV. 2. The method of claim 1, wherein said helium nuclei comprise alpha particles. 3. The method of claim 1, wherein said helium nuclei comprise alpha particles and said helium nuclei source is controlled to produce alpha particles having an incident energy between 15 MeV and 20 MeV. 4. The method of claim 1, wherein said helium nuclei comprise alpha particles and said helium nuclei source is controlled to produce alpha particles having an incident energy selected to preferentially trigger a 226Ra[α,n]229Th reaction producing ground state 229Th, while minimizing production of ground state 228Th. 5. The method of claim 1, wherein said helium nuclei comprise helium-3 particles. 6. The method of claim 1, wherein said helium nuclei comprise helium-3 particles and said helium nuclei source is controlled to produce helium-3 particles having an incident energy selected to preferentially trigger a 226Ra[3He,γ]229Th reaction producing ground state 229Th, while minimizing production of ground state 228Th. 7. A method for producing ground state 229Th, comprising the steps of:providing a target material comprising 226Ra,bombarding said target material with helium nuclei from a cyclotron nuclei source to form ground state 229Th, andcontrolling said cyclotron to produce said helium nuclei with an incident energy between 8 and 20 MeV. 8. The method of claim 7, wherein said helium nuclei comprise alpha particles. 9. The method of claim 7, wherein said helium nuclei comprise alpha particles and said cyclotron is controlled to produce alpha particles having an incident energy between 15 MeV and 20 MeV. 10. The method of claim 7, wherein said helium nuclei comprise alpha particles and said cyclotron is controlled to produce alpha particles having an incident energy selected to preferentially trigger a 226Ra[α,n]229Th reaction producing ground state 229Th, while minimizing production of ground state 228Th. 11. The method of claim 7, wherein said helium nuclei comprise helium-3 particles. 12. The method of claim 7, wherein said helium nuclei comprise helium-3 particles and said cyclotron is controlled to produce helium-3 particles having an incident energy selected to preferentially trigger a 226Ra[3He,γ]229Th reaction producing ground state 229Th, while minimizing production of ground state 228Th. 13. A method for producing ground state 229Th, comprising the steps of:providing a target material comprising 226Ra,bombarding said target material with alpha particles from an alpha particle source to form ground state 229Th, andcontrolling said alpha particle source to produce said alpha particles with an incident energy between 15 and 20 MeV. 14. The method of claim 1, wherein said alpha particle source is controlled to produce alpha particles having an incident energy selected to preferentially trigger a 226Ra[α,n]229Th reaction producing ground state 229Th, while minimizing production of ground state 228Th.
	description	The invention is described below in the context of representative embodiments that are not intended to be limiting in any way. Since the respective figures accompanying the description of the embodiments are schematic, the figures do not provide actual or relative dimensions of the depicted components. As a result of a thorough investigation into the causes of deteriorated accuracy of projected pattern elements in peripheral regions of chips, as observed especially whenever charged-particle-beam (CPB) microlithography is performed with a high beam-acceleration voltage, it has been discovered that the actual cause is a xe2x80x9cproximity effectxe2x80x9d imparted by adjacent chips imprinted on the lithographic substrate (xe2x80x9cwaferxe2x80x9d). Normally, to perform CPB microlithography of a LSI pattern, for example, a first step involves defining the actual pattern. This step includes determining the manner in which the pattern is to be divided, on the reticle, into subfields and the manner in which individual pattern elements are to be configured in the respective subfields on the reticle. Determining how pattern elements are to be defined takes into consideration proximity effects expected to be imparted to the pattern elements when the elements are transfer-exposed onto the wafer. A xe2x80x9cproximity effectxe2x80x9d is a phenomenon that is manifest on the pattern as transfer-exposed onto the wafer, wherein unwanted regions (especially adjacent to pattern elements actually exposed) of the resist become exposed. The phenomenon is caused by: (1) backscattering, into adjacent areas of resist, of charged particles of the beam by atoms and molecules of the resist and by atoms of the substrate on which the beam is incident, and (2) secondary electrons emitted by the resist on which the beam is incident. The backscattered and secondary electrons penetrate into adjacent areas of resist, causing unwanted xe2x80x9cexposurexe2x80x9d of the adjacent areas. Defining individual pattern elements while taking into account proximity effects involves configuring the pattern elements, to be defined on the reticle, in a manner serving to offset the proximity effect. In other words, at least certain pattern elements are defined on the reticle with respective profiles that are different from actual designed profiles so that, when the pattern elements are projected onto the wafer, the resulting respective images as formed in the resist have profiles that more closely approximate the desired as-designed profiles. Hence, determining how pattern elements are to be defined on the reticle is performed with consideration given to a range over which respective proximity effects are significant, and to pattern elements that may be located within the range. Determining this range (termed the xe2x80x9cproximal rangexe2x80x9d) begins with a determination of the xe2x80x9cbackscattering radiusxe2x80x9d). The backscattering radius is the width of the Gaussian function corresponding to backscatter of electrons whenever the energy-intensity distribution of the incident beam is approximated by a linear combination of Gaussian functions. This radius is used to describe a distribution of energy intensity of cumulative exposure energy. The energy-intensity distribution is a function indicating the exposure energy received by surrounding points whenever an electron beam is incident at a point. The proximity effects imparted by pattern elements within the backscattering radius cannot be neglected. The proximal range (range over which proximity effects imparted by other pattern elements is significant) typically is wider than the backscattering radius, and is determined by a trade-off of accuracy versus calculation time (i.e., the greater the desired accuracy with which proximity effects are corrected, the longer the time required to calculate the proximity effects and their required corrections). Typically, by way of example, the proximal region extends more than three times the backscattering radius. The calculations result in determinations of the manner and extent to which individual pattern elements, as defined on the reticle, are to be reconfigured. Typically, these calculations are performed using a computer-simulation technique. Information relevant to performing these calculations and determining the width of the proximal region is set forth, for example, in U.S. patent application Ser. Nos. 09/704473 and 09/861210, incorporated herein by reference. At the relatively low beam-acceleration voltages conventionally used, backscattering radii tend to be small relative to the normal distance between adjacent (neighboring) chips on the wafer. As a result, adjacent chips on the wafer usually did not cause significant proximity effects on pattern elements projected onto peripheral regions of a chip. Hence, determining how pattern elements are to be defined on the reticle conventionally did not include a consideration of proximity effects caused by neighboring chips. However, with increases in beam-acceleration voltage, the backscattering radius and hence the proximal range is increased correspondingly. Hence, it has been discovered that a consideration must be given, when configuring pattern elements to be defined on the reticle, to proximity effects imparted to the elements by neighboring chips when the pattern is transfer-exposed from the reticle to the wafer. FIG. 1 schematically depicts, in plan view, an exemplary chip pattern 10 having outer dimensions of 2000 xcexcmxc3x972000 xcexcm. The chip pattern 10 comprises a large L-shaped pattern element 11, having arm widths of 100 xcexcm, extending along the left edge and bottom edge and a small line 12, having a width of 70 nm and a length of 50 xcexcm, situated in the upper right corner opposite the L-shaped element 11. FIG. 2 shows, in plan view, an exemplary arrangement of nine individual chips 13A-13I, each having a chip pattern as shown in FIG. 1, on the surface of a wafer. The chips 13A-13I are spaced 80 xcexcm apart in this example. Generally, the smaller the distance between chips on the wafer, the better in terms of production efficiency, because each wafer yields a correspondingly larger number of chips. Attention is directed, in FIG. 2, to the center chip 13E that is surrounded on all sides by neighboring (adjacent) chips. With respect to the element 12E extending along the upper right edge, investigations were made of a first situation in which backscatter from neighboring chips 13B, 13C, 13F was ignored, and a second situation in which backscatter from the neighboring chips was considered. Exemplary parameters in the investigations were: a silicon substrate, a beam-acceleration voltage of 125 kV, a backscatter radius of 47.2 xcexcm, a demagnification ratio of 1/4, and a backscatter coefficient of 0.7. In addition, the blur produced by the CPB optical system was 70 nm. In the investigation in which backscatter from adjacent chips is ignored, a sufficient distance was assumed to exist between the large L-shaped element 11E and the small element 12E in the chip 13E. Hence, it was assumed that transfer-exposure of the small element 12E was not influenced by any proximity effect from other pattern elements or chips. Under such conditions the corresponding pattern element as defined on the reticle (for a demagnification ratio of 1/4) had a width of 280 nm. The resulting pattern element 12E as transfer-exposed onto the chip 13E (FIG. 3(a)) was defined on the reticle as having a width of 70 nm. Exposure time was established so that the threshold exposure dose for the resist was exceeded in the element 12E. In actuality, in the chip 13E backscatter is received by the pattern element 12E from the respective large pattern elements 11B, 11C, 11F proximally located in the neighboring chips 13B, 13C, 13F, respectively. Taking this backscatter into account, the dosage received at the element 12E on the wafer is increased, as shown in FIG. 3(b). Consequently, the linewidth of the element 12E as formed on the wafer is increased by this proximity effect to 70.9 nm (FIG. 3(b)). Hence, in the investigation in which the contribution, to exposure of the pattern element 12E on the wafer, of backscatter from the large elements 11B, 11C, 11F is taken into account, calculations reveal that the width of the pattern element 12E as defined on the reticle should be changed slightly to offset this proximity effect. According to the calculations, the linewidth of the pattern element 12E as defined on the reticle is decreased to 276 nm. Exposure of this element onto the wafer yields a dosage, as received on the wafer, as shown in FIG. 3(c), in which the linewidth of the pattern element is restored to the desired width of 70 nm. With respect to the method described above, it is noted that a complete chip located peripherally (near an edge) of the wafer does not have a full complement of neighboring chips. As a result, whenever a pattern on the reticle is configured under the assumption in which a full set of neighboring chips exist, the reticle may not be configured optimally for exposure of certain chips (especially peripherally located chips). This situation is shown in FIG. 4, in which an edge 15 of the wafer 14 is depicted relative to the chips 13A-13I formed on the wafer. Each of the chips 13A-13I has a respective pattern such as that shown in FIG. 1. Note that the chips 13D-13E and 13G-13H can be made into finished microelectronic devices, but the chips 13A-13C, 13F and 13I cannot because each of these chips is missing at least a portion thereof (due to the chips extending partially or fully off the edge 15 of the wafer 14). The chips 13A, 13B, 13F, and 13I extending partially off the wafer edge 15 are said to be xe2x80x9cstraddlingxe2x80x9d the wafer edge. Conventionally, it is regarded as wasteful to expose any portions of chips such as 13A, 13B, 13C, 13F, and 13I. Consequently, exposure of these chips conventionally is not performed so as not to compromise throughput. Rather, exposure conventionally is performed only of the chips 13D-13E and 13G and 13H. In FIG. 4, features that conventionally are exposed are shaded more darkly than features that are not. However, whenever exposure of the chips 13A-13C, 13F, 13I is not performed, exposure of the chips 13D, 13E, and 13H is unaffected by backscatter from the neighboring chips 13A-13C, 13F, 13I. But, since the reticle (used to expose all the chips on the wafer) is configured to account for such backscatter, the chips 13D, 13E, 13H as transfer-exposed onto the wafer do not have optimally corrected pattern elements. To prevent this problem, exposure also is performed of portions of the chips 13A, 13B, 13F, and 13I that straddle the edge 15 of the wafer 14 but nevertheless will not become actual chips. (The chip 13C is not exposed at all because it is entirely off the wafer 14 where it cannot contribute any backscatter anyway.) By exposing the wafer in this manner, since all the chips actually formed on the wafer are affected substantially equally by backscatter by neighboring chips (or portions of chips). This allows a reticle configured to offset the resulting proximity effects to have an equally curative effect on all the chips. I.e., by exposing portions of the xe2x80x9cpartialxe2x80x9d chips 13A, 13B, 13F, and 13I, the full chips 13D, 13E, 13H will have patterns that are as design-mandated and as fully corrected as any other chip (e.g., chip 13G) on the wafer. Note that, with respect to the xe2x80x9cpartialxe2x80x9d chips (i.e., chips 13A, 13B, 13F, 13I), it is unnecessary to expose all the subfields of such chips. Rather, only those subfields of such chips capable of producing backscatter that can reach proximally situated xe2x80x9ccompletexe2x80x9d chips need be exposed. For example, as shown in FIG. 5, in the xe2x80x9cpartialxe2x80x9d chips 13A, 13B, 13F, and 13I, only subfields situated in the respective regions denoted 16A, 16B, 1F6, and 16I, respectively, are exposed. (In FIG. 5, exposed portions are shaded more darkly than portions that are not exposed.) FIG. 6 is a flow chart of a microelectronic-device manufacturing method that includes a microlithography step performed using a CPB-microlithography method as described herein. The depicted method generally comprises the main steps of wafer production (wafer preparation), reticle production (reticle preparation), wafer processing to form chips, chip dicing and assembly, and inspection of completed chips. Each step usually comprises several sub-steps. The wafer-preparation step results in production or preparation of a wafer suitable for use as a lithographic substrate. This step typically involves growth of a monocrystalline silicon ingot, cutting of the ingot into wafers, and polishing the wafers. The reticle-preparation step results in production or preparation of a reticle that defines a desired pattern to be transferred lithographically to the wafer. This step includes performing methods as described below. The wafer-processing step comprises multiple steps resulting in the formation of multiple layers of vertically and horizontally interconnected circuit elements, and is discussed below. The chip dicing and assembly step involves cutting out (dicing) of individual chips from the wafer after completing formation of all the constituent layers of the chips on the wafer, and assembling each individual chip into a respective package with connecting leads and the like. The inspection step involves qualification and reliability testing and inspection of completed devices. Among the main steps, wafer processing is key to achieving the smallest feature sizes (critical dimensions), best inter-layer registration, and device performance. In the wafer-processing step, multiple circuit patterns are layered successively atop one another in each die on the wafer, wherein the formation of each layer typically involves multiple sub-steps. Usually, many operative microelectronic devices (chips or dies) are produced on each wafer. Typical wafer-processing steps include: (1) Thin-film formation involving formation of a dielectric layer for electrical insulation or a metal layer for connecting wires. The films are produced by CVD, sputtering, or other suitable technique. (2) Oxidation of the thin-film layer or other portion of the wafer surface. (3) Microlithography to form a resist pattern, according to the reticle pattern, for selective processing of the thin film or the substrate itself. (4) Etching (e.g., dry etching) or analogous step to etch the thin film or substrate according to the resist pattern. (5) Doping as required for implantation of dopant ions or impurities into the thin film or substrate according to the resist pattern. Doping can include a thermal treatment to facilitate diffusion of the impurity. (6) Resist stripping to remove the resist from the wafer. (7) Wafer inspection. Wafer processing is repeated as required (typically many times) to fabricate the desired microelectronic devices on the wafer. FIG. 7 is a flow chart of typical steps performed in microlithography, which is a principal step in wafer processing. The microlithography step typically includes: (1) application of resist to the wafer, wherein a suitable resist is coated on the wafer substrate (which can include a circuit element formed in a previous wafer-processing step); (2) exposure step (using a CPB exposure method as described above), to expose the resist with the desired pattern and form a latent image; (3) development step, to develop the exposed resist and obtain an actual pattern in the resist; and (4) optional annealing step, to stabilize the developed pattern in the resist. Commonly known technology can be used for any of the steps summarized above, including the microelectronic-device manufacturing process, wafer-processing, and microlithography. Hence, detailed descriptions of these processes are not provided. Whereas the invention has been described in connection with multiple representative embodiments and examples, it will be understood that the invention is not limited to those examples. On the contrary, the invention is intended to encompass all modifications, alternatives, and equivalents as may be included within the spirit and scope of the invention, as defined by the appended claims.
	description	This application is a US 371 application from PCT/RU2017/001010 filed Dec. 29, 2017, the technical disclosure of which is hereby incorporated herein by reference. The invention refers to the power engineering and can be used in dual circuit reactors of the nuclear power units at the nuclear power plants with water-water energetic reactor, pressurized water and steam-generating unit with horizontal steam generators. For the purposes of description of this invention, the used terms have the following meanings: “hot” header—the steam generator header comprising the coolant from the first reactor circuit “cold” header—the header through which the primary circuit coolant leaves the steam generator and enters the suction line of the main circulating pump; header “pockets”—the dead zones formed between the primary circuit headers and internal surface of the steam generator bottom and impairing the purge quality; “hot” bottom—steam generator bottom from the “hot” header side; “cold” bottom—steam generator bottom from the “cold” header side; “salt” compartment—the area in the steam generator with the highest dissolved salts concentration in the boiler water from the “cold” bottom side; active water treatment—a system of filters designated for purge water treatment from the corrosion products and impurities in ion form. At the nuclear power plants (NPP) with double loop VVER reactors (pressurized water reactors, PWR), to ensure successful functioning of the reactor compartment it requires a variety of process systems, one of which, and both of the primary and secondary circuits, is a steam generator that, on the one hand generates the vapour used as working body of the steam turbine for electricity generation that is due to the heat produced in the reactor, and on the other hand, it is intended reliably and continuously ensure the reactor core cooling. When the steam generating unit is in operation, the primary circuit coolant is pumped through its steam generators that sets forth specific requirements to its design and operation. In particular, the steam generating unit is enclosed into the containment dome, wherein to ensure tightness, a number of ducts in the containment intended for process lines must be minimized. The NPP reliability, particularly, depends on the organization of the secondary circuit water chemistry (WC). The WC disturbances can lead to premature failure of the steam generators being the major parts of the steam generating unit, i.e can significant decrease its operational reliability and life time. To ensure reliable and safe operation of the steam generator, it is necessary timely to remove from the heat exchange surface of the pipes and out of the steam generator the deposits where the corrosive impurities of the boiler water are concentrated. The high concentration of these impurities in particular steam generator zones can lead to the corrosion cracking of the weld joints and heat exchange parts of the steam generator. The undesired impurities are removed out of the steam generator by blowdown that is performed both continuously and regularly as well as combining the continuous and regular blowdown. There is the known steam generating unit with the reactor VVER-1000 comprising four identical steam generators that represent the horizontal single-casing dual circuit heat exchangers with the immersed heat exchange surface. The steam generator consists of a casing made in the form of horizontal drum connected with the horizontal steam header and feed water header, the steam generator includes the inlet (“hot”) and outlet (“cold”) vertical pipe headers of the primary coolant and blowdown connection. To maintain normal salt mode, the steam generator is provided with continuous and periodic blowdowns/I. N. Nignatulin, B. I. Nignatulin. Nuclear Power Plants. Workbook for Institutes, M., Energoatomizdat, 1986. P. 120-122/There is the known steam generating unit of the dual circuit reactor with the blowdown and drain system, comprising four steam generators enclosed into the tight volume of the reactor, with horizontal casing with lower casing component, “hot” and “cold” headers of the primary coolant with the pockets created between them and bottom surface of the steam generator, salt compartments, steam header and blowdown and drain system. The coolant from the primary circuit enters the “hot” header. It releases its heat to the steam generator water and, cooled down, enters, through the “cold” header, the suction line of the main circulating pump. The feed water is supplied to the steam generator. The dried steam leaves the steam header, and then it is supplied to the turbine through the steampipes. The blowdown system of the steam generators consists of two blowdown lines being individual for each steam generator and intended for independent continuous and regular blowdowns, wherein the impact of blowdown of individual steam generators on each other is excluded. The extraction for continuous blowdown is made from the salt compartment, and for the regular—from the pockets of the “hot” and “cold” headers and blowdown lines from the lower casing component. The headers of continuous and regular blowdown of each steam generator are made separate and taken out of the tight volume until included into the connection pipeline of the blowdown expansion tanks. Each steam generator is also provided with individual drain tube connected to the drain pipeline, and then the drain pipelines of the steam generators are combined in one drain header, taken out of the tight volume and directed to the drain coolant B. I. Lukasevich, N. B. Trunov, et al. Steam Generators of VVER Reactor Units for Nuclear Power Plants, M: ICC Akademkniga, 2004, PP. 83-86/. The disadvantages of the known steam generating unit are the required availability of blowdown expansion tank to decrease the pressure to the deaerator parameters, and the energy loss to volume return to the expansion tank, to the secondary circuit, increases, insignificant consumption of the blowdown water that increases the WC normalization time, separate taking the continuous and regular blowdown header and drain header out of the tight volume that reduces the operational reliability due to the additional reduction of tightness, as well as the necessity of process communication with the engine hall and system operation independently from the engine hall equipment, because the steam release from the expansion tank is made into the steam header of the deaerator, and the treated blowdown water is returned to the deaerator or expansion tank of the engine hall drains. There is also the known blowdown and drain steam generator system designed for maintaining the chemical condition and draining them (http://www.stroitelstvo-new.ru/nasosy/paroturbinnaya-ustanovka.shtml). The system operates in continuous blowdown mode and in the mode of combination of continuous and regular blowdowns, wherein the sludge and suspended matters are removed from the generator. The blowdown water from the steam generator enters the blowdown expansion tank, and then is pumped via the regenerative blowdown heat exchanger, additional coolant and treatment system to the turbine unit low pressure heaters. In the draining mode, the water from the steam generators flows downstream the drain pipelines to the drain tank, and then is pumped for treatment as the tank level increases. The disadvantages of the known technical solution are the required pressure decrease to the deaerator parameters using the blowdown expansion tank and, as a consequence, the increased energy losses for the blowdown water return to the secondary circuit, process communication with the engine hall and dependence of the system operation on the engine hall equipment as the evaporation is released from the blowdown expansion tank to the steam header of the deaerator, the treated blowdown water is returned to the deaerator or drain expansion tank of the engine hall, as well as insufficient consumption of the blowdown water, thus increasing the WC normalization time. The technical problem to be solved by the applied invention consists in creating the steam generating unit of dual circuit reactor with high performance reliability and life cycle. The technical result is in reduction of the secondary circuit WC normalization time due to the increased consumption of the blowdown water with simultaneous reduction of energy losses to return of the treated blowdown water to the secondary circuit and ensuring the self-sustained operation of the steam generating unit. The technical problem is solved, and the technical result is achieved due to that the steam generating unit of dual circuit reactor with blowdown and drain system comprises four identical steam generators enclosed into the protection tight volume, with horizontal casing with lower casing component, hot and cold headers of the primary coolant with the pockets and salt compartment; each steam generator is connected to the steam header, feed water supply pipeline, blowdown lines from the salt compartment, from the lower casing component and pockets of the primary circuit headers, wherein all the blowdown lines of each steam generator are combined into a single blowdown header of the steam generator with further combination into the common blowdown header of the steam generators that is connected to the regenerative heat exchanger inlet, with the discharge line connected to the blowdown aftercooler and the drain cooling line is connected to the discharge line of the blowdown aftercooled water that is taken out of the protective tight volume and connected to the active water treatment system with the discharge line of the treated blowdown water of the steam generators and mounted thereon by means of, at least, one treated blowdown water pump which pressure line is made in the protective tight volume and connected to the regenerative heat exchanger intertubular space inlet, with the outlet connected to the feed water supply pipelines of the relevant steam generator via the common pipeline for the treated blowdown water supply and pipelines for treated blowdown water supply of each steam generator, wherein the blowdown aftercooled water pipeline, after taken out of the protective tight volume, is provided with the steam generator drain and discharge pipeline connected to the water drain tank. It is preferable that the blowdown water discharge pipeline of the steam generators was provided with three pumps—operating, reserve and repair. The steam generating unit works as follows. The coolant from the primary circuit enters the “hot” header 3 of each steam generator 1, releases its heat to the steam generator 1 water and, cooled down, enters, through the “cold” header 2, the suction line of the main circulating pump (not shown in the scheme). The feed water is supplied to each steam generator 1 via the feed water supply pipelines 6, 7, 8 and 9 to the first, second, third and fourth steam generators 1, respectively. The dried steam is taken out of the steam header 5 of each steam generator 1, and then it is supplied to the turbine through the steampipes (not shown in the scheme). The blowdown consists in continuous and regular extraction of some portion of the boiler water from the points where the corrosion products, salts and sludge are most probably accumulated. Via the blowdown pipelines 10, the flows of continuous and regular blowdowns are removed from the salt compartments 4 of each of the steam generators 1, blowdown pipelines 11 from the lower part of generators and pipelines 12 from the pockets 36 of the headers 2 and 3, then the flows of both continuous and regular blowdowns are combined in single blowdown headers 13, 14, 15 and 16 of the steam generators 1, and then in the common header 17 of the steam generators 1. The main consumption of the continuous blowdown is arranged via the blowdown pipelines 10 from the salt compartment 4 placed on the “cold” bottom of the casing. The regular blowdown of the steam generators is performed both from the salt compartment 4 and via the blowdown pipelines 11 of the lower part of generators and pipelines 12 from the pockets 36 of the headers 2 and 3. In the normal operation, the regular blowdown of the steam generators is performed in a cyclic way by increasing the consumption of one of four steam generators any time. Via the common header 17 the blowdown flows enter the regenerative heat exchanger 18 pipes where they are cooled down and wherefrom they are supplied via the regenerative heat exchanger 18 discharge pipeline 19 for aftercooling in the blowdown aftercooler and drain cooling line 20, and then flowing via the discharge line of the blowdown aftercooled water 21 they enter the active water treatment system 23 where the blowdown water of the steam generators are treated from the corrosion products and impurities in ion form, wherein the chemical condition of the secondary circuit is maintained for corrosion products and dissolved impurities. The treated blowdown water pump 25 mounted on the treated blowdown water discharge pipeline 24 of steam generators 1 supplies, via the pressure line 26, the cooled and treated from undesired impurities blowdown water to the regenerative heat exchanger 18 intertubular space where it is heated due to the blowdown water cooling that enters the regenerative heat exchanger 18 pipes via the common blowdown header 17 of the steam generators 1. The treated water, via the treated blowdown water main pipeline 27 and treated blowdown water pipelines 28, 29, 30 and 31 of each steam generator 1, respectively, is supplied as additional water to the feed water supply pipelines 6, 7, 8 and 9 of the relevant steam generator, and then via the feed water supply pipelines 6, 7, 8 and 9 to the first, second, third and fourth steam generators 1, respectively. The draining is conducted as follows: when the steam generator 1 is shut down, the working medium of the steam generator 1 is removed via the blowdown pipelines 11 from the lower part of the generator and pipelines 12, from the pockets 36 of the headers 2 and 3, via the single blowdown header 13 and common blowdown header 17 of the steam generators, with the route through the regenerative heat exchanger 18 and discharge pipeline 19 of the regenerative heat exchanger 18 it is supplied to the blowdown aftercooler and drain cooling line 20 to cool down, and then via the discharge line of the blowdown aftercooled water 21 the medium is supplied to the drain and discharge pipeline 32 of all four steam generators, and then to the water drain tank from the steam generators 33, wherefrom it is pumped by the automatic pump 34 via the water discharge pipeline of the steam generators 35, and directed for treatment or further disposal. The blowdown water pump 25 of steam generators is intended for the treated blowdown water return after active water treatment 23 to the steam generators 1 via the system of the feed water supply pipelines 6, 7, 8 and 9, the reserve and repair pumps can be also provided. The regenerative heat exchanger 18 is intended for initial cooling of the blowdown water supplied for active water treatment 23 and further heating of the treated blowdown water after active water treatment 23 in various operation modes of the power unit—during start-up, power operation and cooling down. The blowdown aftercooler and drain cooling line 20 is intended for aftercooling of the steam generator blowdown water supplied for active water treatment 23 during the power unit operation, cooling down and start-up. When the power unit is shut down, the blowdown aftercooler and drain cooling line 20 is intended for cooling the media drained from the steam generators. In the claimed technical solution, the blowdown and drain system of the steam generating unit is implemented in the close loop, makes it possible to use the blowdown water as additional for the feed water of the steam generators, by preserving the blowdown water high pressure over the entire blowdown water treatment cycle, thus reducing the energy losses for the blowdown water return to the secondary circuit. Due to the increase blowdown consumption of the steam generators up to 140 t/h, the CC normalization time is reduced, and the improved WC of the secondary circuit provides for prolonging the service life of the steam generators, and respectively, the steam generating unit as a whole, and the reduced number of process lines laid through the containment improves its tightness, and no process communication with the engine hall makes the steam generating unit self-sustained.
	claims	1. A method for producing an aqueous solution of lead-212, comprising:(a) producing lead-212 by decay of radium-224 in a generator comprising a cation-exchange resin, wherein the radium-224 is bound to the resin;(b) eluting the lead-212 from the resin with a first aqueous solution comprising from 1.5 mol/L to 2.5 mol/L of a strong acid to form a second aqueous solution comprising the lead-212 and radiological and chemical impurities;(c) purifying the lead-212 from the radiological and chemical impurities by liquid chromatography on a column, the column comprising a stationary phase comprising 4,4′(5′)-di-tert-butylcyclohexano-18-crown-6 in solution in an organic diluent not miscible with water, the liquid chromatography purification comprising:contacting the stationary phase with the second aqueous solution;washing the stationary phase with a third aqueous solution comprising from 0.1 mol/L to 0.5 mol/L of a strong acid; andeluting the lead-212 from the stationary phase with a fourth aqueous solution having a pH from 5 to 9 to form a fifth aqueous solution comprising the lead-212; and(d) submitting the fifth aqueous solution to a bacteriological purification to prepare the aqueous solution of lead-212. 2. The method of claim 1, wherein the first and third aqueous solutions are hydrochloric acid or nitric acid solutions. 3. The method of claim 1, wherein the fourth aqueous solution is an ammonium acetate solution. 4. The method of claim 3, wherein the fourth aqueous solution comprises from 0.15 mol/L to 1 mol/L of ammonium acetate. 5. The method of claim 1, wherein the bacteriological purification comprises circulating the fifth aqueous solution through a bacteriological filter. 6. The method of claim 1, further comprising collecting the aqueous solution of lead-212. 7. The method of claim 1, wherein the aqueous solution of lead-212 comprises less than 11 ppb of lead other than lead-212, less than 2 ppb of vanadium, manganese, cobalt, copper, molybdenum, cadmium, tungsten and mercury, less than 20 ppb of iron, and less than 50 ppb of zinc. 8. A method for producing an aqueous solution of lead-212 in an automated manner, comprising the steps of:(a) producing lead-212 by decay of radium-224 in a generator comprising a cation-exchange resin and wherein the radium-224 is bound to the resin;(b) eluting the lead-212 from the resin with a first aqueous solution comprising from 1.5 mol/L to 2.5 mol/L of a strong acid to form a second aqueous solution comprising the lead-212 and radiological and chemical impurities, the elution comprising drawing the first aqueous solution from a first solution source and injecting the first aqueous solution into the generator by a first pump;(c) purifying the lead-212 from the radiological and chemical impurities by liquid chromatography on a column, the column comprising a stationary phase comprising 4,4′(5′)-di-tert-butylcyclohexano-18-crown-6 in solution in an organic diluent not miscible with water, and the liquid chromatography purification comprising:contacting the stationary phase with the second aqueous solution, the contacting comprising a circulation of the second aqueous solution from the generator to the column by means for connecting the generator with the column;washing the stationary phase with a third aqueous solution comprising from 0.1 mol/L to 0.5 mol/L of a strong acid, the washing comprising drawing the third aqueous solution from a second solution source and injecting the third aqueous solution into the column by the first pump; andeluting the lead-212 from the stationary phase with a fourth aqueous solution having a pH from 5 to 9 to form a fifth aqueous solution comprising the lead-212, the elution comprising drawing the fourth aqueous solution from a third solution source and injecting the fourth aqueous solution into the column by the first pump;(d) submitting the fifth aqueous solution to a bacteriological purification to prepare the aqueous solution of lead-212, the bacteriological purification comprising a circulation of the fifth aqueous solution from the column to a bacteriological purification filter by means for connecting the column with the bacteriological purification filter; and(e) collecting the aqueous solution of lead-212 in a flask, the collection comprising a circulation of the aqueous solution of lead-212 from the bacteriological purification filter to the flask by means for connecting the bacteriological purification filter with the flask;wherein the first and second pumps, the means for connecting the generator with the column, the means for connecting the column with the bacteriological purification filter, and the means for connecting the bacteriological purification filter with the flask are commanded by an electronic processor. 9. The method of claim 8, wherein the first and third aqueous solutions are hydrochloric acid or nitric acid solutions. 10. The method of claim 8, wherein the fourth aqueous solution is an ammonium acetate solution. 11. The method of claim 10, wherein the fourth aqueous solution comprises from 0.15 mol/L to 1 mol/L of ammonium acetate. 12. The method of claim 8, wherein the aqueous solution of lead-212 comprises less than 11 ppb of lead other than lead-212, less than 2 ppb of vanadium, manganese, cobalt, copper, molybdenum, cadmium, tungsten and mercury, less than 20 ppb of iron, and less than 50 ppb of zinc.
	abstract	Disclosed is a diagnostic resonant cavity for determining characteristics of a charged particle beam, such as an electron beam, produced in a charged particle accelerator. The cavity is based on resonant quadrupole-mode and higher order cavities. Enhanced shunt impedance in such cavities is obtained by the incorporation of a set of four or more electrically conductive rods extending inwardly from either one or both of the end walls of the cavity, so as to form capacitive gaps near the outer radius of the beam tube. For typical diagnostic cavity applications, a five-fold increase in shunt impedance can be obtained. In alternative embodiments the cavity may include either four or more opposing pairs of rods which extend coaxially toward one another from the opposite end walls of the cavity and are spaced from one another to form capacitative gaps; or the cavity may include a single set of individual rods that extend from one end wall to a point adjacent the opposing end wall.
	claims	1. A composition for dust suppression and containment of radioactive products of combustion after the extinguishing of a fire with a radiation factor, comprising÷ an aqueous solution of polyvinyl alcohol, a glycerine and a surfactant, wherein it contains a mixture of an anionic, a non-ionic and an amphoteric surfactant as a surfactant with the following proportions of components, wt %:an aqueous solution of polyvinyl alcohol (in terms of a3.0-7.0mass fraction of dry product)a glycerine0.1-0.3a surfactant11.0-29.0Watera remainderwherein the anionic surfactant is alkylbenzene sulfonate, the non-ionic surfactant is cocamidopropyl dimethylamine oxide, and the amphoteric surfactant is cocamidopropyl betaine. 2. The composition of claim 1, wherein an anionic surfactant alkylbenzene sulfonate is mixed with other substances in the amount of 1.0-3.0 wt %. 3. The composition of claim 1, wherein a non-ionic surfactant cocamidopropyl dimethylamine is mixed with other substances in the amount of 8.0-22.0 wt %. 4. The composition of claim 1, wherein an amphoteric surfactant cocamidopropyl betaine is mixed with other substances in the amount of 2.0-4.0 wt %.
	summary
042347980	claims	1. A shielding transport and storage receptacle for radioactive materials, especially for nuclear-reactor fuel elements, comprising: an elongated body cast in one piece and formed with a lateral wall surrounding a chamber for said material and a bottom, said body being composed of cast iron or cast steel; a shielding cover connected to said body and closing said chamber at an upper end thereof with a thickness of radiation absorbing material limiting escape of radiation into the environment, at least one passage cast in said body and communicating with said chamber at a low point thereof, said passage terminating at an upper end of said body; means including an additional cover removably affixed to said body for closing said passage at said end of said body; and a further passage cast in said body and communicating with said chamber at an upper portion thereof, said further passage terminating at said end, means being provided for closing said further passage, the means for closing said further passage being said additional cover. an elongated body cast in one piece and formed with a lateral wall surrounding a chamber for said material and a bottom, said body being composed of cast iron or cast steel; a shielding cover connected to said body and closing said chamber at an upper end thereof with a thickness of radiation absorbing material limiting escape of radiation into the environment; at least one passage cast in said body and communicating with said chamber at a low point thereof, said passage terminating at an upper end of said body; means including an additional cover removably affixed to said body for closing said passage at said end of said body; and a further passage cast in said body and communicating with said chamber at an upper portion thereof, said further passage terminating at said end, said passages being formed in the inner half of the thickness of said body and the outer half of the thickness thereof around said chamber being provided with a plurality of channels receiving a radiation moderator material, said channels being closed by said additional cover. 2. The receptacle defined in claim 1 wherein said body is formed along said wall with outwardly extending mutually parallel cooling ribs interrupted by gaps. 3. The receptacle defined in claim 1 wherein said body has a greater wall thickness at said end than elsewhere along said body. 4. The receptacle defined in claim 1 wherein said ribs are cast in one piece with said body. 5. A shielding transport and storage receptacle for radioactive materials, especially for nuclear-reactor fuel elements, comprising: 6. The receptacle defined in claim 5 wherein said body is formed along said wall with outwardly extending mutually parallel cooling ribs interrupted by gaps. 7. The receptacle defined in claim 5 wherein said body has a greater wall thickness at said end than elsewhere along said body. 8. The receptacle defined in claim 5 wherein said ribs are cast in one piece with said body.
	description	1. Field of the Invention This invention relates to a shipping container for nuclear fuel components and, in particular, to such a container for unirradiated nuclear fuel assemblies and nuclear fuel rods. 2. Related Art In the shipping and storage of unirradiated nuclear fuel elements and assemblies which contain large quantities and/or enrichments of fissile material, U235, it is necessary to assure that criticality is avoided during normal use, as well as under potential accident conditions. For example, nuclear reactor fuel shipping containers are licensed by the Nuclear Regulatory Commission (NRC) to ship specific maximum fuel enrichments; i.e., weights and weight-percent U235, for each fuel assembly design. In order for a new shipping container design to receive licensing approval, it must be demonstrated to the satisfaction of the NRC that the new container design will meet the requirements of the NRC rules and regulations, including those defined in 10 CFR § 71. These requirements define the maximum credible accident (MCA) that the shipping container and its internal support structures must endure in order to maintain the sub-criticality of the fuel assembly housed therein. U.S. Pat. No. 4,780,268, which is assigned to the assignee of the present invention, discloses a shipping container for transporting two conventional nuclear fuel assemblies having a square top nozzle, a square array of fuel rods and a square bottom nozzle. The container includes a support frame having a vertically extending section between the two fuel assemblies which sit side by side. Each fuel assembly is clamped to the support frame by clamping frames which each have two pressure pads. This entire assembly is connected to the container by a shock mounting frame and a plurality of shock mountings. Sealed within the vertical section are at least two neutron absorber elements. A layer of rubber cork cushioning material separates the support frame and the vertical section from the fuel assemblies. The top nozzle of each of the conventional fuel assemblies is held along the longitudinal axis thereof by jack posts with pressure pads that are tightened down to the square top nozzle at four places. The bottom nozzle of some of these conventional fuel assemblies has a chamfered end. These fuel assemblies are held along the longitudinal access thereof by a bottom nozzle spacer which holds the chamfered end of the bottom nozzle. These, and other shipping containers, e.g., RCC-4, for generally square cross-sectional geometry pressurized water reactor (PWR) fuel assemblies used by the assignee of the present invention, are described in Certificate of Compliance Number 5454, U.S. Nuclear Regulatory Commission, Division of Fuel Cycle and Material Safety, Office of the Nuclear Material Safety and Safeguards, Washington, D.C. 20555. U.S. Pat. No. 5,490,186, assigned to the assignee of the present invention, describes a completely different nuclear fuel shipping container designed for hexagonal fuel, and more particularly, for a fuel assembly design for a Soviet-style VVER reactor. Still, other shipping container configurations are required for boiling water reactor fuel. There is a need, therefore, for an improved shipping container for a nuclear fuel assembly that can be employed interchangeably with a number of nuclear reactor fuel assembly designs. There is a further need for such a fuel assembly shipping container that can accommodate a single assembly in a lightweight, durable and licensable design. These and other needs have been partially resolved by U.S. Pat. No. 6,683,931, issued Jan. 27, 2004 and assigned to the assignee of the instant invention. The shipping container described in this latter patent includes an elongated inner tubular liner having an axial dimension at least as long as a fuel assembly. The liner is preferably split in half along its axial dimension so that it can be separated like a clamshell for placement of the two halves of the liner around the fuel assembly. The external circumference of the liner is designed to be closely received within the interior of an overpack formed from an elongated tubular container having an axial dimension at least as long as the liner. Preferably, the walls of the tubular container are constructed from relatively thin shells of stainless steel and the liner is coaxially positioned within the tubular container with close-cell polyurethane disposed in between. Desirably, the inner shell includes boron impregnated stainless steel. The tubular liner enclosing the fuel assembly is slidably mounted within the overpack and the overpack is sealed at each end with end caps. The overpack preferably includes circumferential ribs that extend around the circumference of the tubular container at spaced axial locations that enhance the circumferential rigidity of the overpack and form an attachment point for peripheral shock-absorbing members. An elongated frame, preferably of a birdcage design, is sized to receive the overpack within the external frame in spaced relationship with the frame. The frame is formed from axially spaced circumferential straps that are connected to circumferentially-spaced, axially-oriented support ribs that fixedly connect the straps to form the frame design. A plurality of shock absorbers are connected between certain of the straps and at least two of the circumferential ribs extending around the overpack, to isolate the tubular container from a substantial amount of any impact energy experienced by the frame, should the frame be impacted. Although the shipping container described in the aforementioned '931 patent is a substantial improvement in that it can accommodate different fuel assembly designs through the use of complementary liners while employing the same overpack and birdcage frame, that improvement has been taken one step further by U.S. Pat. No. 6,748,042, assigned to the assignee of the instant invention. The '042 patent describes a transport system that provides a liner and overpack system that will achieve the same objectives as the '931 patent while further improving the protective characteristics of the transport system and the ease of loading and unloading the nuclear fuel components transported therein. The shipping container includes an elongated tubular container, shell or liner designed to receive and support a nuclear fuel product such as a fuel assembly therein. The interior of the tubular liner preferably conforms to the external envelope of the fuel assembly. The exterior of the tubular container has at least two substantially abutting flat walls which extend axially. In the preferred embodiment, the cross-section of the tubular member is rectangular or hexagonal to match the outer envelope of the fuel assembly and three of the corner seams are hinged so that removal of all the kingpins along a seam will enable two of the sidewalls to swing open and provide access to the interior of the tubular container. The tubular container or liner is designed to seat within an overpack for transport. The overpack is a tubular package having an axial dimension and cross-section larger than the tubular liner. The overpack is split into a plurality of circumferential sections (for example, two sections, a lower support section and an upper cover, or three sections, a lower support section and two upper cover sections) that are respectively hinged to either circumferential side of the lower support section and joined together when the overpack is closed. The lower support section includes an internal central V-shaped groove that extends substantially over the axial length of the overpack a distance at least equal to the axial length of the tubular liner. Shock mounts extend from both radial walls of the V-shaped groove to an elevation that will support the tubular liner in spaced relationship to the groove. The axial location, number, size and type of shock mount employed is changeable to accommodate different loadings. The tubular liner is seated on the shock mounts, preferably with a corner of the liner aligned above the bottom of the V-shaped groove. The top cover section (sections) of the overpack has a complementary inverted V-shaped channel that is sized to accommodate the remainder of the tubular liner with some nominal clearance approximately equal to the spacing between the lower corner of the tubular liner and the bottom of the V-shaped groove. The ends of the overpack are capped and the overpack sections are latched. Though the transport system of the '042 patent provides a substantial improvement in the protective characteristics and ease of loading and unloading of the nuclear fuel components being transported, further improvement in the ease of loading and unloading the liner is desired. This invention provides an improved liner that facilitates the loading and unloading of nuclear components, especially components having hexagonal contour such as the VVER nuclear fuel assemblies. The liner comprises an elongated tubular container designed to receive and support the nuclear fuel product or components therein. An exterior of the tubular container has at least two substantially flat walls with at least one circumferential end of at least one of the walls having a hinged interface with a stationary wall of the container to provide access to the interior thereof. The hinged wall extends axially in the direction of one end of the container and terminates a pre-selected distance short of the corresponding end of the stationary wall. The stationary wall has a lateral groove on an interior surface thereof at an elevations starting substantially at the elevation of the one end of the hinged wall. An access cover is slidable in the groove in the stationary wall to close off the one end of the container so that the interior of the container may be accessed either through the one end by sliding out the access cover, or from the side by rotating the hinged wall. The elongated tubular container has the other end opposite the one end capped and sealed and is sized to fit within the overpack of the '042 patent. Preferably, a mechanism is provided for locking the access cover in a closed position when the container is prepared for transport. Desirably, the locking mechanism is a pair of radially extending arms that pivot proximate one end on each of the radially extending arms that faces towards the center of the access cover. The pivot enables the radially extending arms to rotate from a position orthogonal to the axis of the elongated tubular container toward the axis. Each of the radially extending arms extends at a distal end into a slot in the stationary wall that extends axially to the one end of the stationary wall so that when the radially extending arms are rotated into a horizontal position and engage the slot in the stationary wall, the access cover cannot slide in the groove. In this preferred embodiment, the radially extending arms are laterally restrained in a slot in an outwardly projecting face of the access cover. Preferably, the outwardly-projecting face of the access cover is formed from a raised fork having two spaced prongs of a given width that form the walls of the slot in the outwardly-projecting face of the access cover. A hole is formed in the width of the wall of each prong that is aligned with a hole in the corresponding radially extending arm when the radially extending arm is rotated in the horizontal position to engage the slot in the outwardly-projecting face of the access cover. Thus, when a pin is inserted through the holes when the radially extending arm is in the horizontal position, the radially extending arm is locked in engagement with the slot in the stationary wall. Preferably, the liner has at least two hinged walls that interface at their non-hinged circumferential ends in a closed position. One of the non-hinged circumferential ends of the hinged wall has an axially extending tongue and the other of the non-hinged circumferential ends of the hinged wall has an axially extending groove that mates with the tongue when the two hinged walls are in the closed position. Preferably, the stationary and hinged walls of the liner are constructed from three extruded sections. In another embodiment, the access cover has an axially-extending lip extending in the direction of the hinged door. The lip of the access cover extends over an outer surface of the hinged door at the one end when the access cover is fully seated in the groove. Thus, when the access cover is fully seated to close off the one end of the tubular liner, it prevents the hinged door from rotating toward an open position. In still another embodiment, the access cover includes a hold-down plate supported on an underside of the cover. The hold-down plate is adjustable in the axial direction to bring pressure on the nuclear product being transport to secure the nuclear product against a bottom member of the elongated tubular liner. Preferably, in the withdrawn position, the hold-down plate is secured within a recess in the access cover. In the preferred embodiment, this invention provides a transport system for transporting nuclear fuel assemblies and particularly, nuclear fuel assemblies having a hexagonal profile such as those employed in the VVER nuclear reactors. An exemplary VVER 1000 nuclear fuel assembly 2 manufactured by Westinghouse Electric Company LLC, which is the assignee of the present invention, is shown in FIG. 1. The fuel assembly 2 includes a top nozzle 4, a hexagonal array of a plurality of fuel rods 6 and a bottom nozzle 8. The top nozzle 4, the fuel rods 6 and the bottom nozzle 8 are positioned about a central longitudinal axis 9 of the fuel assembly 2. The top nozzle 4 includes a cylindrical outer barrel 10 having a top end 11 and two lifting lugs 13 (only one is shown), a cylindrical inner barrel 12 which telescopes into the outer barrel 10, and a shoulder 14 between the outer barrel 10 and the inner barrel 12. The fuel rods 6 are held in the hexagonal array by a plurality of hexagonal grids 16 spaced longitudinally along the fuel rods 6. The exemplary fuel assembly 2 includes 9 hexagonal grids 16. Each of the grids 16 has six sides. The bottom nozzle 8 includes a longitudinally-extending recess 18 formed by a hexagonal barrel 20, a spherical taper 22, and a cylindrical barrel 24 which has a diameter smaller than the hexagonal barrel 20. Disposed on the cylindrical barrel 24 are two alignment pins 25 (only one is shown). The spherical taper 22 interconnects the hexagonal barrel 20 and the cylindrical barrel 24 which forms a bottom end 26 of the fuel assembly 2. The longitudinally-extending recess 18 tapers towards the bottom end 26 and also forms an internal shoulder between the hexagonal barrel 20 and the bottom end 26. The fuel assembly 2 will be secured within a liner 28 which will be described hereafter with respect to FIGS. 3, 5, 6, 7, 8 and 9. The liner 28 will, in turn, be secured within an overpack 30 which is intended to protect the fuel assembly 2 from impacts and fires. The overpack 30 and the internal components of the nuclear fuel product containment and transport system of this invention is illustrated in FIG. 2. A tubular liner, sometimes referred to as container or shell 28, constructed from a material such as aluminum, houses the nuclear fuel assembly 2. The tubular liner 28 is suspended over a V-shaped groove 32 in the overpack 30 and supported on shock mounts 32 that are affixed in a recess 34 in an upper wall section of the groove 32 and spaced along the axial length of the lower overpack support section 36. The shock mounts can be those identified by part number J-3424-21, which can be purchased from Lord Corporation, having offices in Cambridge Springs, Pa. Angle irons 24 can be used at the corners of the tubular liner 28 to spread the load on the liner walls. The number and resiliency of the shock mounts are chosen to match the weight of the liner, which depends upon the nuclear product being transported within the liner 28. The orientation of the lower section 36 of the overpack 30 is fixed by the legs 40 so that the weight of the liner 28 holds the liner centered in the groove 32. One capped end 42 of the overpack 30 forms part of the lower overpack support section 36, while a second capped end 44 is formed as an integral part of the top cover 46. The end 44 of the upper overpack segment 46 seals against the lip 48 in the lower support section 36. Keys 50 on each side of the upper section 46 of the overpack 30 fit in complementary keyways in the lower overpack support section 36, as can be better appreciated from the frontal view shown in FIG. 3. FIG. 3 shows a frontal view of the shipping container system 27 of this invention with the end plate 44 removed. Both the top segment 46 and the bottom segment 36 of the overpack 30 are formed from hollow stainless steel sheet 52. For example, an 11 gauge stainless steel shell filled with polyurethane can be employed. Preferably, in this embodiment, the polyurethane has a minimum 3″ (7.62 cm) thickness. In the preferred embodiment, the hollow channel in the overpack 54 is shaped to substantially conform to the outer profile of the tubular liner 28 and the walls of the hollow channel 54 can be lined with a neutron-absorbing material, such as a half-inch (1.27 cm) of borosilicate. Alternately, the outer surface of the tubular liner 28 can be lined with a neutron-absorbable material, such as a ⅛″ (0.318 cm) thick layer of borosilicate, or a combination of neutron-absorbing material on the walls of the tubular liner 28 and the walls of the hollow channel 54 can be employed. FIG. 3 provides a better view of the recess 34 that the shock mounts 32 are mounted in than can be derived from FIG. 2. Similarly, the keys 50 and keyways 56 that aid in positioning the top section 46 on the lower support section 36 of the overpack 30 are shown more clearly in FIG. 3. The top and bottom overpack sections 46 and 36, respectively, are formed from a stainless steel shell 58 that is filled with polyurethane 60. Thermal insulation 62 can be incorporated to line the interior of the stainless steel sheet overpack shell 52. The top segment 46 of the overpack is latched to the bottom support segment 36 in the preferred embodiment using the latch assembly shown in FIG. 4. Both the lip 53 on the upper overpack section 46 and the lip 55 on the lower overpack section 36 include a plurality of axially-spaced slots. A latchbar 66 is affixed to either the upper lip 53 or the lower lip 55 in a manner to permit the clamp arm 64 to slide within a corresponding slot in the lip. For example, with the latchbar 66 coupled to the lower lip 55, the clamp arm 64 would protrude through the corresponding slot in a downward direction and have a large protruding end to anchor the latchbar 66 to the lower lip 55. The upper clamp arm 64 can have an L-shape, as shown in FIG. 4, so that when the lip 53 is seated over its corresponding clamp arm 64, the latchbar 66 can be moved in a direction into the Figure to lock the upper section 46 to the lower section 36 of the overpack 30. The clamp arm 64 can then be secured in that locked position and an external lever can be used to slide the latchbar 66 to an open and closed position with an approximate 4″ stroke desirable. To facilitate the locking and unlocking action, a low-friction coating can be applied to the sliding surfaces. FIG. 5 illustrates a perspective view of an open tubular liner 28 with a fuel assembly 2 positioned therein. As previously mentioned with respect to FIG. 1, the fuel assembly 2 is made up of a parallel spaced array of fuel elements 6 that are maintained in spaced relationship and in position by grid straps 16, bottom nozzle 8 and a top nozzle which is not shown. The grid straps are constructed in an egg crate design to maintain the spacing between the fuel elements 6 that form flow channels for the reactor coolant to flow through during reactor operation. The fuel assembly 2 is seated on a neoprene or cork rubber bottom pad 72 which is affixed to the bottom 68 of the tubular liner 28. The neoprene or cork rubber pad 72 supports and cushions the fuel assembly 2. A similar arrangement is provided above the fuel assembly 2 by a neoprene or cork rubber hold down plate that is supported by a top access cover to the tubular liner 28 as will be more fully described with regard to FIG. 8. In this embodiment, the tubular container has four stationary sides, 74, 76, 78 and 80 (shown in FIG. 6) which are affixed to the bottom 68 of the tubular liner 28. The tubular liner 28 has two movable sides 70 and 71 which are hinged to the adjacent edges of the stationary sides 74 and 78 through hinges 82 that rotate around a kingpin 84. The two movable sides are in turn connected, when latched, by similar hinges 82, with the insertion of the kingpin in the hinge forming the latch. In this way, the movable sides 70 and 71 can be opened from any of the hinged seams to provide access to the interior of the tubular liner 26 from a number of different directions to facilitate loading and unloading in different environments that may present obstructions. For quick access, the hinges connecting a given side may be connected by a single kingpin that extends through the lower hinge and up through each of the individual hinges 82 extending up the hinged seam. The tubular liner 28 is preferably constructed out of aluminum of a thickness, for example, of 0.375″ (0.9525 cm). The interior walls of the sides 70, 71, 74, 76, 78 and 80 are covered with an iron ferrite composite sheet 86 and neoprene or cork rubber pads with magnetic backing 88 attached and affixed by the magnetic force at the grid elevations to seat the neoprene or cork rubber side of the pads against the outside straps of the grids 16. The magnetic coupling on the pads make them adjustable to accommodate different nuclear fuel component designs. The neoprene or cork rubber pads are not as hard as the material that the grids are constructed of and secures the grids in position when the movable sides 70 and 71 are in the closed position, without damaging the grids, and cushions the fuel assembly 2 during transport. The inside of the tubular liner 28 can be used to transport other fuel components, such as fuel rods, separately by employing inserts within the tubular container 28 that will hold those components securely. Alternatively, clips on the backs of the neoprene or cork rubber pads can be supported in slots at multiple elevations on the interior walls of the sides 70, 71, 74, 76, 78 and 80. Axial adjustment of the pads can be made by moving the pads from slot to slot. FIG. 6 provides a better view of the iron ferrite composite sheet 86 and hinged locations. FIG. 6 shows the bottom 68 of the tubular line 28 supported on the shock mounts 32 within the overpack 30. From FIG. 6, it can be appreciated that one of the opening edges of the movable walls 70 and 71 has a groove that extends axially down its entire length while the other of the edges of the movable walls 70 and 71 has an axially extending tongue that mates with the groove when the movable walls 70 and 71 are in the closed position, as shown in FIG. 6. Though the preferred embodiment is shown with a hexagonal liner compatible with VVER 1000 fuel, it should be appreciated that the novel features of this invention can be applied equally as well to a square reactor fuel assembly such as those employed in Westinghouse Electric Company LLC designed reactors. This invention has particular benefit for handling hexagonal fuel because it provides additional choices for access to the interior of the liner for loading the hexagonal fuel which can present handling difficulties that are not encountered with square fuel configurations. FIG. 7 shows the top 90 of the liner 28 with an access cover 92 in the open position. With the access cover 92 removed from the top of the tubular liner 28, as shown in FIG. 7, the fuel assembly 2 may be loaded into the liner from the top of the liner as an alternative to being loaded from the side through the movable sides 70 and 71. To close the liner 28, the access cover 92 slides within a circumferential groove 94 in the stationary walls 74, 76, 78 and 80. The access cover 92, on its upper surface 103, has diametrically opposed raised forks 104 that are connected by a central hub 112. The tines 114 of the forks 104 define a groove 113 within which radially extending arms 98 are laterally restrained and pivot about pivot points 96. When the access cover 92 is in the closed position seated within the grooves 94, the radially extending arms 98 can be rotated about the pivots 96 to the horizontal position in which they engage the slots 108 in the upper end 90 of the stationary walls 74 and 80, thus locking the access cover 92 in the closed position. A retaining pin or lock can then be inserted through aligned holes 100 in the fork tines 114 and alighned holes 102 in the radially extending arms 98 to restrain the radially extending arms in the locked position. A downwardly projecting lip 110 on the access cover 92 seats up against the outer upper surface of the movable sides 70 and 71 to lock the movable sides in the closed position when the access cover 92 is in place fully seated in the groove 94. FIG. 8 shows another perspective view of the upper portion of the liner 28 with the access cover 92 in an open position showing the underside of the access cover. The underside of the access cover has a recess 116 in which the hold down plate 118 can be withdrawn as the access cover 92 is inserted into the annular groove 94 to close off the top of the tubular liner 28. A hole in the top of the access cover 106 (shown in FIG. 7) provides access to an adjustment screw that adjust the axial elevation of the hold down plate 118 so that it brings pressure against the top nozzle 4 of the fuel assembly 2 to restrain the fuel assembly in a secure position within the tubular liner 28. FIG. 9 shows the access cover 92 in the fully seated closed position locking the movable sides 70 and 71 in the closed position. While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular embodiments disclosed are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims and any and all equivalents thereof.
	abstract	A recirculation pump motor is supplied with a power from a unit auxiliary middle voltage bus through a power supply system including a first circuit breaker, a voltage source inverter, and a second circuit breaker electrically connected in series to provide a no-load operation by use of the voltage source inverter. The second circuit breaker may be multiplexed with more than one breaker electrically connected in series. An existing nuclear plant using a induction motor driving a hydraulic coupling mechanically coupled to a synchronous generator for driving the recirculation pump, such as an MfG set, may be subjected to a method of replacing the induction motor, the hydraulic coupling, and the synchronous generator with the voltage source inverter and a circuit breaker through electrically disconnection and removal.
050158643	claims	1. A manually propelled radiation shield comprising a frame, caster wheel means for supporting the frame for universal movement on the ground, a flexible sheet of material capable of preventing the transmission of radiation carried by the frame, said frame including a generally annular thrust means constructed and arranged to be engaged by the body of a user to propel the frame over the ground in accordance with walking movement of the user. 2. The apparatus of claim 1, wherein said thrust means includes a movable member moved between an operative position wherein said user exerts a force against said movable member to propel said frame and a release position wherein said user enters and exits said annular thrust means. 3. The apparatus of claim 2, wherein said movable member is mounted for pivotal movement between a generally horizontal operative position and a generally vertical release position. 4. The apparatus of claim 3, wherein said movable member is mounted about a horizontal axis. 5. The apparatus of claim 1, wherein said annular thrust means includes a resilient pad disposed to be engaged by the waist of the user. 6. The apparatus of claim 5, wherein said annular thrust means includes a pair of overlapping resilient pads, and releasable fastening means for removably connecting the pads together. 7. The apparatus of claim 1, wherein said caster wheel means comprises a plurality of casters. 8. The apparatus of claim 1, wherein said caster wheel means comprises two groups of a plurality of casters, each group disposed at a side of said frame and arranged in a generally triangular pattern. 9. The apparatus of claim 8, wherein a first caster of each group is disposed in generally vertical alignment with the forward extremity of said frame. 10. The apparatus of claim 1, and including a head shield removably attached to the upper end of said frame and disposed to shield the head of the operator. 11. A mobile radiation shield, comprising a frame including a pair of generally vertical frame members, each frame member including an upper forwardly extending curved shoulder section, wheel means for supporting the frame for universal movement on the ground, a flexible apron including a radiation resistant material supported by said shoulder sections of said frame members, and annular thrust means interconnecting said vertical frame members and located beneath said shoulder sections, said thrust means being constructed and arranged to be engaged by the body of a user to thereby propel manually said frame over the ground in accordance with walking movement of said user. 12. The apparatus of claim 11, and including means for adjusting the height of each vertical frame member. 13. The apparatus of claim 12, wherein each vertical frame member includes a pair of telescopic sections, and locking means to lock the telescopic sections together. 14. The apparatus of claim 11, and including a generally curved frame section connecting the lower portions of said vertical frame members and disposed beneath said annular thrust means. 15. The apparatus of claim 14, and including a second apron containing a radiation resistant material and connected to said curved frame section. 16. The apparatus of claim 11, and including a head piece including a lead glass window, a bib attached to the lower end of said head piece and extending laterally of said window, and attaching means for removably attaching said bib to said shoulder sections of said frame members. 17. The apparatus of claim 11, and including a pair of shoulder flaps containing a radiation resistant material, flexible connecting means for connecting said flaps together, and attaching means for attaching said connecting means to the shoulder sections of said vertical frame members. 18. The apparatus of claim 16, wherein said attaching means comprises hook and loop fasteners. 19. The apparatus of claim 11, wherein said wheel means includes a plurality of casters associated with the lower end of each vertical frame member, a tubular brace connecting at least one of said casters to the respective vertical frame member and extending rearwardly of said vertical frame member, and weight means connected to said brace. 20. The apparatus of claim 19, wherein said brace is hollow and said weight means comprises a finely divided metal disposed within said hollow brace. 21. The apparatus of claim 19, wherein three casters are associated with each vertical frame member, a first of said three casters being vertically aligned with said vertical frame member, the second of said casters being disposed laterally outward of said vertical frame member and a third of said casters being disposed to the rear of said vertical frame member. 22. A mobile radiation shield, comprising a frame, wheel means for supporting the frame for universal movement on the ground, said frame including a thrust bar having an annular configuration and located between the upper and lower ends of said frame and disposed to be engaged by the body of a user to propel the frame over the ground in accordance with walking movement of the user, a flexible sheet of material capable of preventing the transmission of radiation carried by the frame and covering said annular thrust bar, said thrust bar having a rear section that is selectively removed from the annular configuration to provide a ga through which a user enters the frame, and means for securing said rear section in the annular configuration.
	abstract	The object of this invention is to provide a method for mitigating a stress corrosion cracking of reactor structural material which makes it possible to suppress the rise in the main steam line dose rate without secondary effects such as a rise in the concentration of radioactive cobalt-60, etc. in the reactor water. Hydrogen and a reductive nitrogen compound containing nitrogen having a negative oxidation number (for example, hydrazine) are injected into the core water of boiling water nuclear power plant. By injecting the reductive nitrogen compound containing nitrogen having a negative oxidation number into the core water, the stress corrosion cracking of structural material of reactor can be mitigated without side reactions such as a rise in the concentration of cobalt-60, etc.
043615058	summary	BACKGROUND OF THE INVENTION This invention relates to a process for treating a radioactive waste, and more particularly to a process for treating a radioactive liquid waste, suitable for shaping pellets having a low hygroscopicity. Heretofore, radioactive liquid wastes produced in radioactive material handling facilities of nuclear power plants, etc. have been classified according to their characteristics, and treated or stored. For example, a large amount of radioactive liquid wastes in a solution state produced in boiling water-type nuclear power plants, such as a liquid waste resulting from regeneration of ion exchange resin, which contains sodium sulfate (Na.sub.2 SO.sub.4) as a main component, etc. is solidified by cement or asphalt in drums. Used ion exchange resin, filter aid, etc. are stored in tanks in a slurry state. Thus, in order to reduce storage space, attempts have so far been made to dry the radioactive liquid waste in the slurry state into powder by a drier such as a thin film drier, etc., then pelletize the powder into pellets by a pelletizer such as a briquetting machine, etc., and storing the pellets, thereby reducing a considerable volume of the radioactive wastes coming from the nuclear power plants as the effluent. In that case, it is necessary to prevent the pellets from breakage or scattering as powder, etc. at the transportation or handling such as the filling into drums, etc. Japanese Laid-open Patent Application Specification No. 93865/75 (laid open on July 26, 1975) discloses a process for treating a radioactive liquid waste by means of a binder so as to increase the strength of the pellets, where a radioactive liquid waste containing the binder is dried into powder by a spray drier, the powder is shaped into pellets, and the pellets are stored in storage tanks. A process for treating a radioactive liquid waste to reduce the number of drums containing pellets solidified by asphalt is proposed in Japanese Laid-open Patent Application Specification No. 34200/77 (laid open on Mar. 15, 1977), where a radioactive liquid waste is made into powder, the powder is shaped into pellets, the pellets are stored for a specific period, and the pellets whose radioactivity is reduced by the storage are filled into drums, and solidified by asphalt. According to said process, number of pellets to be filled in a drum can be increased, and thus the number of the required drums can be reduced, as compared with the case of filling the pellets into drums immediately after the shaping. However, the stability of pellets must be maintained during the storage, and it is necessary to prevent the pellets from deliquescence, moisture absorption, etc. However, the pellets prepared according to the conventional processes are very unsatisfactory in meeting said requirements. To overcome these disadvantages, a process of impregnating pellets with a liquid plastic monomer such as styrene monomer, adding a polymerization initiator such as benzoyl peroxide thereto, and polymerizing the monomer is proposed in Japanese Patent Publication No. 8880/78 (published on Apr. 1, 1978), where an apparatus for impregnating the pellets with the liquid plastic monomer and the polymerization initiator is required, which complicates the system, and furthermore it is difficult to impregnate the individual pellets with the liquid plastic monomer and the polymerization initiator continuously and rapidly. For example, the impregnation will be quite inefficient when carried out one by one, and the number of the pellets waiting for the impregnation is increased. Furthermore, when the polymerization is carried out while placing the pellets, for example, on a plate, the pellets themselves will adhere to the plate, and when a plurality of the pellets are in contact with one another, the plurality of the pellets will adhere to one another. Thus, the handling must be inevitably made with much care. SUMMARY OF THE INVENTION An object of the present invention is to shape pellets of radioactive waste with a low hygroscopicity. Another object of the present invention is to shape pellets of radioactive waste with a high strength. Other object of the present invention is to shape pellets with a high strength and a low hygroscopicity without increasing the amount of radioactive waste. The present invention is characterized by mixing a binder containing silicon into a radioactive liquid waste, the binder being soluble or dispersible in the radioactive liquid waste, then making the radioactive liquid waste into powder, and shaping the powder containing the binder into pellets. As the binder, a silane coupling agent, which is an organosilicon monomer containing at least two different reactive groups in one molecule, is preferably used. Furthermore, it is desirable to use the silane coupling agent and colloidal silica at the same time.
	summary
	abstract	Provided are a probe and an apparatus for measuring a thickness of an oxide layer of a fuel rod, capable of testing claddings of inner and outer fuel rods of a nuclear fuel assembly without disassembling the nuclear fuel assembly. The probe includes a fuel rod transfer region on which an eddy current sensor capable of continuously testing claddings of outer fuel rods of a fixed nuclear fuel assembly is mounted. Further, the apparatus includes a frame in which a cylinder driven in upward and downward directions is mounted, a first probe connected to one side of the cylinder in order to test claddings of outer fuel rods of a nuclear fuel assembly, and a second probe connected to the other side of the cylinder in order to test claddings of inner fuel rods of the nuclear fuel assembly.
	summary
	claims	1. An instrumented capsule for material irradiation tests in research reactors, comprising: a capsule main body installed in a vertical irradiation hole of a research reactor pool, said capsule main body consisting of: a shell opened at upper and lower ends thereof; a plurality of heat media set in said shell; a plurality of specimens set at a center and peripheral areas of each of the heat media; upper and lower reflectors installed on an upper end of an uppermost heat medium and under a lower end of a lowermost heat medium, respectively; a plurality of insulators interposed between adjacent heat media and positioned above and under the upper and lower reflectors, respectively; a spacer set in said shell at a position above an uppermost insulator; a spring seat installed above the spacer; a specimen compressing spring to bias the spring seat, thus compressing the specimens; temperature control means for controlling a temperature inside the shell, said temperature control means consisting of a vacuum control pipe and a heater; detecting means consisting of both a thermocouple used for detecting a temperature of the specimens and a dosimeter used for detecting a quantity of neutron radiation; upper and lower end plugs mounted to the upper and lower ends of the shell so as to seal the ends of said shell; and a lower fixing unit assembled with the lower end plug; and connecting means for connecting said capsule main body to a capsule control system installed outside the reactor pool. 2. The instrumented capsule according to claim 1 , wherein an upper guide spring unit is fitted over the upper end of said shell so as to place the capsule main body at a center of the vertical irradiation hole, said upper guide spring unit consisting of upper and lower fixing rings fitted over said shell, and a plurality of wire springs connected between the upper and lower fixing rings and projected outward in radial directions so as to come into contact with an inner surface of the irradiation hole when the capsule main body is installed in the irradiation hole. claim 1 3. The instrumented capsule according to claim 1 , wherein said heat media are brought, at external surfaces thereof, into contact with an inner surface of the shell, and each have one or more specimen seating holes to receive the specimens. claim 1 4. The instrumented capsule according to claim 3 , wherein said specimen seating holes have circular or rectangular cross-sections in a same manner as the specimens, and are formed at the center and peripheral areas of each of the heat media. claim 3 5. The instrumented capsule according to claim 1 , wherein said lower fixing unit comprises: claim 1 a lower end cap mounted to said lower end plug; a rod tip connected to a center of said lower end cap and vertically extending downward, with a plurality of locking blades formed on a lower portion of said rod tip and locked to a fixing slot formed on a receptacle provided in said irradiation hole; a stopper movably fitted over said rod tip; and a stopper spring fitted over said rod tip at a position between the stopper and the lower end cap, thus normally biasing the stopper downward in a vertical direction. 6. The instrumented capsule according to claim 5 , wherein said stopper comprises: claim 5 a plurality of holes formed in said stopper so as to allow a coolant flowing from the bottom of the irradiation hole to smoothly flow upward through said stopper without being disturbed by the stopper; a plurality of guide pins projected on a circumferential surface of said stopper in radial directions such that the guide pins come into contact with the inner surface of said irradiation hole when the capsule main body is installed in the irradiation hole; and an annular ring connecting outside ends of said guide pins so as to support said guide pins. 7. The instrumented capsule according to claim 1 , wherein said connecting means comprises: claim 1 a rigid protection tube connected to an upper end of said capsule main body so as to guide said vacuum control pipe and said thermocouple end said heater having several control wires control wires extending from there from inside said capsule main body while protecting said vacuum control pipe and said control wires; a flexible guide tube connected to said protection tube so as to guide said vacuum control pipe and said control wires; and a junction box connected to said guide tube pipe so as to connect said vacuum control pipe and said control wires to said capsule control system installed outside the reactor pool, thus acting as a medium which transmits signals to the capsule control system.
049833502	claims	1. Apparatus for detecting the fall of a control cluster into the core of a nuclear reactor, said core comprising a plurality of zones (Q1, Q2, Q3, Q4) each (Q1) provided with: heat measurement means (T1A, T1B, CP1) for providing a heat flux signal (P1) corresponding to said zone and representative of heat flux removed by the flow of a cooling fluid through said zone; neutron measuring means (CF1) for providing a neutron flux signal (F1) corresponding to said zone and representative of nuclear power in said zone; and a plurality of control clusters, with each of said control clusters being provided with measurement means (CZ1A, CZ1B, . . . ) for providing a cluster position signal (Z1A, Z1B, . . . ) representative of the position of said cluster; said apparatus comprising differentiation and comparison means (12) for receiving "sensitive" signals sensitive to the displacements of the control clusters and for providing corresponding alarm signals whenever said sensitive signals vary at a rate greater than corresponding predetermined alarm thresholds; and logical processor means for providing a cluster fall signal in the presence of a plurality of said alarm signals; said apparatus being characterized by the fact that said alarm signals include at least signals of a first tYpe and of a second type, said first type being constituted by position alarm signals (Z'1A, Z'1B, . . . , Z'2A, Z'2B, . . . , Z'3A, Z'3B, . . . , Z'4A, Z'4B, . . . ) corresponding to said cluster position signals (Z1A, Z1B, . . . , Z2A, Z2B, . . . , Z3A, Z3B, . . . , Z4A, Z4B, . . . ) and a second type being constituted by heat alarm signals (P'1, P'2, P'3, P'4) corresponding to said heat flux signals (P1, P2, P3, P4) and/or by neutron alarm signals (F'l, F'2, F'3, F'4) corresponding to said neutral flux signals (F1, F2, F3, F4), said logic processing means (L1, L2, L3, L4, 14, 18, 22) providing said cluster fall signal (24) on receiving at least two of said alarm signals including at least one of said position alarm signals. primary logic units (L1, L2, L3, L4) each of which (L1) receives said position alarm signals ((Z'2A, Z'2B, . . . ) corresponding to at least one of said core zones (Q2) and at least one of said second type alarm signals (F'1, P'4) corresponding to another of said zones (Q4), and for providing a primary detection signal (D1) when at least one of said alarm signals is present; and a combination circuit (14, 18, 22) receiving said primary detection signals (D1, D2, D3, D4) and said position alarm signals (Z'1A, Z'lB, . . . , Z'2A, Z'2B, . . . , Z'3A, Z'3B, . . . , Z'4A, Z'4B, . . . ) and providing said cluster fall signal (24) when at least two of said primary detection signals and at least one of said position alarm signals are present. 2. Apparatus according to claim 1, characterized in that said logic processing means comprise: 3. Apparatus according to claim 2, characterized by the fact that said differentiation and comparison means (12) are associated with said primary logic units (L1, L2, L3, L4) in such a manner that, together with a corresponding portion of said means, each of said logic units (L1) constitutes an acquisition unit (U1). 4. Apparatus according to claim 3, characterized by the fact that said acquisition units (U1, U2, U3, U4) constitute a succession corresponding to the succession of said zones (Q1, Q2, Q3, Q4) in the core of the nuclear reactor. 5. Apparatus according to claim 4, characterized by the fact that each of said acquisition units (U1) receives a group of said cluster position signals (Z2A, Z2B, . . . ) corresponding to one of said core zones (Q2), said neutron flux signal (F1) corresponding to another core zone (Q1), and said heat flux signal (P4) corresponding to yet another core zone (Q4), such that said neutron flux signals (F1, F2, F3, F4), said heat flux signals (P1, P2, P3, P4), and said groups of cluster position signals (Z1A, Z1B, . . . , Z2A, Z2B, . . . , Z3A, Z3B, . . . , Z4A, Z4B, . . . ) are each received by one and one only of the acquisition units (U1, U2, U3, U4).
	description	This application claims priority of provisional application Ser. No. 61/024,373, filed Jan. 29, 2008; and provisional application Ser. No. 61/083,590, filed Jul. 25, 2008. This invention relates to methods and devices for bacterial, fungal and/or viral sterilization and disinfection, and is more particularly directed to a method and device for disinfecting rooms and similar enclosed areas. Nosocomial, or hospital acquired, infections are common, costly, and sometimes lethal. A recent review of such infections in the cardiac surgery unit of a major hospital revealed a nosocomial infection rate of 27.3% that more than doubled the mortality rate for afflicted patients. The nature of bacteria acquired in the hospital setting differs significantly from bacteria found in a community setting primarily in their resistance to antibiotic therapy. “Historically, staphylococci, pseudomonads, and Escherichia coli have been the nosocomial infection troika; nosocomial pneumonia, surgical wound infections, and vascular access-related bacteremia have caused the most illness and death in hospitalized patients; and intensive care units have been the epicenters of antibiotic resistance. Acquired antimicrobial resistance is the major problem, and vancomycin-resistant Staphylococcus aureus is the pathogen of greatest concern. The shift to outpatient care is leaving the most vulnerable patients in hospitals. Aging of our population and increasingly aggressive medical and surgical interventions, including implanted foreign bodies, organ transplantations, and xenotransplantation, create a cohort of particularly susceptible persons. Renovation of aging hospitals increases risk of airborne fungal and other infections. Significant morbidity, mortality, and costs are associated with these infections. Many factors contribute to these dangerous infections. Most notably is the overuse of antibiotics and poor personal hygiene such as hand washing. Abundant evidence exists, however, that the hospital environment itself contributes to the problem by harboring virulent strains of bacteria, fungi, and viruses, and that many methods commonly used are ineffective and may actually spread contaminants. Attempts to eradicate surface contaminates from the hospital setting have varied greatly in strategy and success. These have ranged from antiseptic soaps to fumigation with formaldehyde gas. Topical antiseptics are problematic for several reasons. First, they have recently been shown to actually induce antibiotic resistances and thus may be adding to the problem. Secondly, many surfaces such as keyboards, television sets, and monitoring controls are difficult if not impossible to decontaminate with liquid disinfectants without harming the electronics. Gas disinfection, while effective, is time consuming, hazardous to workers, and environmentally unwise. Ultraviolet (UV) light has been long used for disinfection and sterilization. Ultraviolet light may be produced artificially by electric-arc lamps. Recently, the widespread availability of low to medium pressure mercury bulbs has led to the development of devices which use UV-C to decontaminate water supplies. UV-C is a high frequency wavelength of light within the ultraviolet band and has been shown to be the most bactericidal type of ultraviolet light. UV-C has wavelengths of about 2800 Å to 150 Å. To date, there are no published efforts to use UV-C to decontaminate or disinfect larger areas such as operating rooms. The only recent availability of the appropriate bulbs as well as significant safety concerns regarding worker exposure to UV-C likely contribute to the lack of efforts to use UV-C outside of self-contained water purification systems. An ultraviolet area sterilizer or disinfector is incorporated into a building structure where concern exists regarding the presence of pathogens on environmental surfaces. Ultraviolet C (UV-C) generators generate UV-C that is directed to architectural partitions of an enclosed area. The architectural partitions reflect UV-C to kill pathogens in the enclosed area. The device transmits a calculated dose of UV-C from a fixture mounted to an architectural partition in the enclosed area. Once an effective cumulative dose of UV-C has been reflected to radiation sensors, as measured by the sensors, the device shuts down. Referring now to the drawing figures, banks of UV-C emitting bulbs 8 are positioned in an architectural partition, which could be a wall, but may be a ceiling 2 of the enclosed area. The enclosed area may be a room located in a building. FIG. 1. In one embodiment, four (4) pairs of medium pressure mercury bulbs may be present in a fixture that is located in a ceiling of a room. FIG. 2. The bulbs may be 48-inch long, 115-Watt UV-C generating lamps or bulbs that produce 300 microwatts of ultraviolet radiation at 1 meter. Other effective UV-C generators or bulbs may be used. Each pair of bulbs is positioned to provide coverage of the entire room. The lamps or bulbs may be positioned between ceiling tiles that are commonly used in commercial buildings, including hospitals and medical clinics. The lamps or bulbs may be positioned in a similar manner to fluorescent bulb arrays that are used as lighting in buildings. One advantage of using the bulbs in multiple fixtures, with the fixtures affixed to walls and/or ceilings of real property is that broad coverage of the room may be achieved, with the UV-C radiation emanating from multiple locations that are remote from each other and over a relatively large area. Optimal positioning of the bulbs according the requirements of the particular room may be achieved. If a portable unit is used, the dissemination of UV-C radiation is limited to a radius around the machine. A base, such as a lighting fixture, is provided for the lamps or bulbs. The base or fixture may be positioned in the ceiling between ceiling tiles and/or HVAC outlets. The lamps or bulbs are positioned to direct UV-C radiation from overhead toward the room structure, and toward furniture 4, fixtures 6 and equipment within the room. The UV-C radiation is reflected from surfaces in the room, and particularly, the flat and preferably light colored wall surfaces, so that the UV-C radiation is received both directly and indirectly, by reflection, to surfaces in the room. Surfaces that are not in a direct, unobstructed line with the UV-C emitters will receive UV-C radiation in a dosage that is effective to achieve adequate disinfection of the room due to reflection from other surfaces in the room. UV-C sensors, such as sensor 18a, may be mounted in the ceiling, such as in ceiling tiles, and positioned so as to receive reflected radiation that is reflected from objects in the room or the walls and floors of the room, without receiving material levels of UV-C radiation directly from the UV-C lamps. That is, one or more of the sensors may be mounted in the same flat, planar architectural partition as the UV-C bulbs or emitters so that the sensors do not receive direct radiation, but rather, they receive reflected radiation that is reflected from surfaces in the room. The bulbs 8 are preferred to be recessed within a fixture, and the sensor may also recessed within a ceiling or similar plane, so that the sensor does not receive direct radiation from the bulbs. Sensors may be mounted on fixtures or objects located in the room. Multiple sensors may be positioned in the room. None of the sensors shown in FIG. 1 receive a material dose of UV-C radiation directly from the UV-C bulbs. Sensors 18b and 18c are shown as being positioned under objects in the room, such as beds, tables or other furniture 4, equipment or fixtures. These sensors are positioned so that they do not receive direct radiation from the UV-C bulbs 8. Similarly, sensor 18a, by being positioned in the ceiling, does not receive direct radiation from the UV-C bulbs, but only such UV-C radiation as is reflected to it. In another embodiment, the bulbs 18 are mounted below the ceiling, but just below the ceiling. The bulbs should be at least two (2) meters above the floor, and it is preferred that the highest bulb is mounted not more than 15 centimeters from the ceiling. In one embodiment, the bulbs are mounted in one or more corners of the enclosed area or room, and are positioned for maximum reflectivity toward the darkest corner of the room. In an embodiment, the bulbs are mounted in a room in a corner and just below the ceiling, with the bulbs directed to a diagonally opposite corner of the room that is the darkest corner of the room. The darkest corner of the room is the corner that is measured to receive the lowest level of reflected radiation. If the run time of the bulbs, as determined by the cumulative dosage received by the sensors, exceeds a pre-set time limit, then an additional bulb or bulbs, spaced apart from other arrays of bulbs, should be added. In one embodiment, a sensor is mounted in the same corner of a room or enclosed area as an array of bulbs. The sensor is positioned so as to not receive direct radiation. The sensor is positioned within and surrounded by a surround which acts to shield to shield the receiver sensor from direct radiation, but allows reflected radiation to be received. This may be accomplished in one embodiment by placing the sensor in a tube, with an opening in the end of the tube allowing the sensor to receive reflected radiation. FIGS. 5A, 5B, 6A, and 6B show an embodiment of UV-C emitting bulbs 108 positioned in a light fixture. The light fixture 122 may be mounted in a ceiling, such as a light fixture that is positioned between ceiling tiles. In this embodiment, fluorescent light bulbs 124 of a type that are generally in use are also present in the fixture. Bulbs 124 provide visible light for lighting the room and may be operated by a wall switch. UV-C sensors 118 are present in the fixture 122. The sensors are preferred to be spaced apart from the UV-C emitting bulbs and mounted in the fixture so that they receive UV-C radiation that is reflected from surfaces in the room, and particularly surfaces that are below the bulbs 108, and the sensors do not receive material levels of direct UV-C radiation from the bulbs. The embodiment of the light fixture shown in FIG. 5 and FIG. 6 uses louvers 120 as a safety device to prevent inadvertent discharge of UV-C radiation when people are in the room, motion is detected, or if objects are in the room that should not be present. The louvers also protect the UV-C bulbs, and help discourage service or replacement by unauthorized persons. The covers or louvers 120 may be formed of an opaque material that prevents visible light and UV-C radiation from passing through. Alternatively, the covers or louvers may be formed of a material that is substantially transparent or translucent to visible light, but prevents or filters UV-C radiation from passing through the cover. In one embodiment, the covers or louvers are movable and are movable in response to commands from the control system. Upon actuation of the device, the louvers are moved by actuators from the position (closed) shown in FIGS. 5A and 6A to the position (open) shown if FIGS. 5B and 6B to reveal the bulbs and permit treatment of the room. Upon completion, the actuators move the louvers to the closed position. The actuators may be driven by electric motors which rotate a drive train to rotate the louvers from the closed position into the open position and back to the closed position. Solenoids may also be used to move the louvers. A feedback device may be employed to provide open or closed louver status. A louver interlock mechanism may be included to prevent accidental activation of the lamps. If coverage of the room cannot be accomplished by arrays of lamps positioned in the walls, the lamps or bulbs may be supplemented with lamps or bulbs positioned within the ceiling. It is preferred that the UV-C emitters are positioned overhead, so that the lamps are not easily reached by persons in the room. Further, positioning the lamps overhead gives the best chance of unobstructed emission of the UV-C radiation and reflection of the radiation, and particularly reflection from wall surfaces. The lamps or bulbs are spaced apart as necessary to achieve UV-C coverage that effectively kills pathogens in the room and within a reasonable time, such as less than about twenty (20) minutes for an operating suite. Portable lamps or bulbs may also be used, with the portable lamps positioned as required within the room. The position of the portable lamps may be dictated by the position of furniture or equipment that is located, or relocated, within the room. In one embodiment, a control box 10 contains components such as a PIC Microcontroller 32 and redundant control relays 28. Motion detectors 12, door interlocks 24 or door strike controls 35, louver status 34, and audible 20 and visible alarms 22 are preferred to be employed for safety. An embodiment of one control structure using a PIC Microcontroller is hereinafter described. Referring now to FIG. 4, door interlocks 24 are shown. These interlocks are activated by the doors of the room in which the device is operating. The door interlocks are switches which disable the device if any one of the switches is opened, such as by opening the door. Door strike controls 35 would not allow the door to be opened while the device is activated. The motion detectors 12 are immediately monitor upon activation of the device and prior to powering of the ballasts 26 and the bulbs, by means of a relay 28. If the motion detectors sense motion at any time during the operation of the device, power to the ballasts and the bulbs is immediately disabled. The device may be controlled by a programmable PIC Microcontroller 32 (PIC). The PIC is contained in the control box 10. PIC® Microcontrollers, available from Microchip Technology, Inc of Chandler, Ariz. may be used. The PIC Microcontroller continuously receives a voltage input from sensors, such as sensors 18, 118, which receive reflected UV-C radiation, although sensors receiving direct radiation may also be monitored. Upon initiation of the device, the sensors continuously sense and measure the level of UV-C radiation which is reflected back to the device. It is preferred that the cumulative UV-C radiation emission is measured from initiation of the emission to termination for each of the sensors. Ideally, reflections from substantially all points in the room will be measured. Placement of the sensor and the number of sensors to be used will be determined by the size, architecture and contents of the room. For example, eight or more sensors that are strategically positioned may be used. Wireless remote UV-C sensors 35 may also be employed to monitor a specific area of concern. If the device is ceiling mounted according to a preferred embodiment of the device, at least one sensor will typically be positioned in the ceiling to receive reflected radiation from the bulbs that are directed away from the ceiling. A sensor or sensors may be positioned in the lighting fixture, but is preferred that the sensor or sensor be positioned so as to receive reflected radiation without receiving UV-C radiation directly from the UV-C bulbs. Each sensor converts the measurement of the level of radiation to a voltage output, which is transmitted to the PIC. The PIC samples the voltage received at intervals and adds the cumulative total of the voltage received. When the PIC determines that the reflected UV-C radiation received by each and every sensor has reached the predetermined minimum cumulative total, the PIC causes the device to shut down, and a signal is given to the operator that the process has been completed. The PIC is programmable to measure voltage inputs as required by the particular application. The PIC receives commands from a control, which may be a wireless remote control 30, or it maybe hardwired to the other operating components 33. The control may be mounted on a wall, but should be mounted outside of the enclosed area or room to be treated so that the control can be operated without exposing the operator to UV-C radiation. A switch activates the remote control. Entry of a security code allows the operator to begin sending commands to the PIC. Commands include Activate, Shutdown, enter Sterilization Mode, or enter Sanitize Mode. The remote is in two-way communication with the device and displays data from the sensor array, time left to sterilize or sanitize the room, and in case of bulb failure, the status of all numbered bank of bulbs. If two-way communication with the remote is lost, the device shuts down. The PIC monitors the motion detectors at least one minute prior to activation of the UV-C bulbs and continues to monitor the detectors during the cycle. The PIC performs all calculations regarding bactericidal doses, stores cumulative dosing data, and system checks to alert the operator of bulb failure. This is needed since an operator should not look at the bulbs to check for burned out bulbs or damaged banks. The PIC can be reprogrammed by attaching a personal computer via a data bus connection, thus allowing alteration to the algorithms to accommodate special circumstances. An example of a protocol for using an embodiment of the device is described. An operator checks the room for occupants, then leaves the room. After securing the room, the operator enters into the control a security code or password, whereupon the operator is prompted to press an “on” switch on the control, activating the device. The audible voice alarms and the motion detectors activate and are preferred to stay on until the entire cycle has been complete. Should the device detect motion, the device automatically deactivates itself until the operator re-enters the room to clear the room, thus preventing the operator from re-activating the device and harming an occupant present in the room. One or more motion detectors are monitored for a preset time, such as one minute, prior to opening the louvers and powering the UV-C bulbs, and then stay active until the cycle is complete, the bulbs are powered down and the louvers closed. The array of bulbs according to the embodiment shown in the drawings emits UV-C radiation downwardly to at a preferred minimum angle of 150 degrees, and more preferably, at substantially 180 degrees, from the array of bulbs, so that all working and occupied surfaces that are below the array of bulbs and are within the enclosed area are exposed to UV-C radiation. As seen in FIG. 1, all furniture, fixtures and objects that are in a direct line with the bulbs 8 will receive direct radiation. Sensors are positioned so as to not receive direct output from the germicidal lamps, thus measuring the dose of UV-C reflected back to the sensors. This data is fed into the microcontroller where it is integrated to compute cumulative exposure of UV-C reflected back from each sensor in the array. In one embodiment, reflecting from the least reflective surface or direction the microcontroller calculates the time the device stays activated to allow an effective dose of UV-C to be emitted within the enclosed area. Several thousand measurements or “snapshots” may be taken for computation of the cumulative dosage. Once sufficient time for a lethal dose of UV-C to be reflected back to the sensors has elapsed, and the minimum cumulative dosage corresponding to each sensor is received by the corresponding sensor, the device may power down the bulbs and sound an “all clear” alert to the operator. If the device uses louvers or similar movable covers for the fixture, then the louvers may move to a closed position that covers the UV-C emitters or bulbs. Upon completion of the cycle, the device is preferred to have disinfected all the exposed surfaces within the room, including the primary shadows such as the back or wall side of all rails, cabinets which are not against the wall, and tables. Surfaces not directly exposed to the UV-C radiation may be sterilized by UV-C radiation reflected from the walls and ceilings. In most environments, there is a presence of what microbiology labs label as “wild spore forms” of bacteria. These bacteria are not known to cause human disease, and yet, are resistant to low doses of UV-C. The dual programming modes of one embodiment of the device allow treatment as required. One mode (Sanitize) kills all known pathogens and requires a lower exposure and thus shorter time. The other mode (Sterilize) kills all species of bacteria and requires greater cumulative doses and therefore more time. Without adequate safety features, daily use of intense UV-C is dangerous and impractical. The device may have motion detectors which assure the room is vacant of personnel prior to activation. Once activated, the device shuts down instantly when motion occurs anywhere in the room being disinfected. If the device loses two-way communication with the control panel it also shuts down. In daily use, safety protocols commonly used in hospitals such as those in use for laser and x-ray devices may be implemented. The device is able to sanitize or sterilize all exposed surfaces in a room. It is able to do so safely, leave no residual toxins or radiation, and generates no adverse environmental side products. In addition, the device is able to notify the operator of the time required to perform this task and automatically shuts down upon completion of sterilization. The inventor has performed tests to prove the efficacy of the device, all of which have been successful. Reflectivity of some paints and other surfaces which absorb rather than reflect UV-C, requiring prolonged exposures of twenty minutes or greater. Specially reflective paints are preferred to be included in the system of area sterilization presented by this invention. The estimated reflection from the wall in a typical hospital room was only 3%. Reflection below three percent is not desirable, since the increased exposure time required to achieve an effective dose may result in degradation of articles which are present in the room and which are exposed to direct UV-C radiation. A minimum of five (5%) percent reflectivity is desired. Through the use of paint or coating that produces a painted wall reflecting 50-85% of the UV-C, the efficiency of the device is increased, allowing for greatly decreased exposure times. It is preferred to have the walls of the room, and other painted surfaces in the room, covered with paint or a similar coating. The paint or coating should have UV-C reflectivity enhancing materials, which may be pigments, in the paint 40. The reflective particles or pigments may be colorants. In one embodiment, the coating includes particles of barium sulfate that will reflect the UV-C radiation. This coating may be transparent to the naked eye, and used to cover painted surfaces such as painted walls or cabinets. In another embodiment, aluminum oxide is used as a pigment that will enhance reflectivity of the UV-C radiation. It is preferred that the paint or coating not have titanium dioxide in a form that absorbs ultraviolet radiation. The paint or coating should be free of materials that are added to the paint or coating for the purpose of absorbing ultraviolet radiation.
	description	The present invention concerns a method of monitoring the operation of a reactor of a nuclear plant, in which the reactor comprises a core having a plurality of fuel assemblies, wherein each fuel assembly includes a plurality of fuel rods, wherein each fuel rod comprises nuclear fuel and a cladding, the nuclear fuel being enclosed by the cladding, the plant also comprising forcing means arranged to force a coolant in a flow through the reactor and the core, and conveying means arranged to convey an off-gas stream from the coolant, wherein the method comprises the steps of; operating the reactor during a normal fuel operation cycle at a given total reactor power, during which fission gases are produced in the fuel rods; continuously measuring during the normal fuel operation cycle a radioactivity level in the off-gas stream for detecting a possible release of fission gases from the fuel rods as a consequence of a fuel leakage due to a defect on the cladding of any of the fuel rods in any of the fuel assemblies, and regularly establishing an instantaneous power distribution in the core during the normal fuel operation cycle and establishing a power distribution pattern based on the instantaneous power distributions over time during the normal fuel operation cycle. The invention also concerns an apparatus for monitoring the operation of a reactor of a nuclear plant, and a nuclear plant. As mentioned above a reactor of a nuclear plant comprises a core with a plurality of fuel assemblies. The fuel assemblies are vertically distributed and each fuel assembly contains a plurality of fuel rods. Each fuel rod comprises a cladding which encloses the nuclear fuel in the form of pellets. Common nuclear fuel material is uranium and/or plutonium. During the normal operation of the nuclear plant the nuclear fuel in the fuel rods is burned up, leading to the formation of fission gases that comprise radioactive inert gases. These fission gases normally stay inside the fuel rods. The environment inside the reactor is demanding for the components positioned therein. The environment is for example highly oxidative and the components are exposed to strong radiation. Furthermore, the generated power inside the reactor is not uniformly distributed throughout the core and some parts are exposed to higher local power levels than other parts. The local power levels may vary for example when a control rod is moved or the water flow and/or the water temperature is changed. The nuclear power producers constantly aim at producing more power, i.e. increasing the effectiveness of the nuclear plant. It is for example desirable to run the fuel assemblies for as long operation cycles as possible to reduce the outage time for refueling. There are however certain limits in the operating conditions of the nuclear plant that are not to be exceeded, to avoid damaging the fuel, and these limits must therefore be carefully monitored. Sometimes during normal operation of the nuclear plant a defect in the cladding of a fuel rod appears. Such a defect may lead to the release of the above mentioned fission gases produced inside the fuel rod. The defect can be of a primary or a secondary nature. A primary defect is the first defect that appears on the cladding. It can appear due to for example mechanical wear or a local power hot spot and is normally a small hole or crack in the cladding. The primary defect may over time develop into a secondary defect which is a larger hole or crack in the cladding. A secondary defect may lead to serious damage on the cladding and eventually a failure of the fuel rod, which in turn may lead to a release of nuclear fuel material into the reactor water. A single fuel rod failure in a fuel assembly could lead to exceeding the allowed radioactivity levels in the coolant, forcing a shutdown of the nuclear plant. Hence, as mentioned above, it is important to monitor the nuclear plant and to be able to effectively locate fuel assemblies containing defect fuel rods either for their removal or for modifying the plant operation to avoid a secondary defect. A fuel assembly containing a defect fuel rod must be removed in order to prevent a total failure of the reactor. One way of monitoring the operation of a nuclear reactor is to use a system that detects the release of fission gases from the fuel assemblies. These kinds of systems are sometimes called activity monitoring systems. The release of fission gases is an indication that a defect on a fuel rod has appeared. The nuclear plant can however continue to be run by for example reducing the power in the part of the reactor where the fuel assembly containing the defect fuel rod is positioned. The fuel assembly in question may thereafter be removed when the operation cycle is over and the reactor is shut down to be charged with new nuclear fuel. To be able to continue running the nuclear plant it is therefore important to find out in what part of the reactor the defect has appeared. A well-known way of doing this is by a method called flux-tilting or power suppression testing, described in U.S. Pat. No. 5,537,450 A. Flux-tilting involves the movement of control rods up and down in the reactor. A control rod is made of a material that is able to absorb neutrons without fissioning itself. The control rods are therefore able to slow down the fission of the nuclear fuel and thereby reduce the power generated in its vicinity. The control rods are distributed throughout the core of the reactor and can be independently moved up and down to control the power in different positions of the core. In the flux-tilting method the control rods are moved up and down in the core of the reactor and at the same time the off-gas stream from the reactor is analyzed for the detection of fission gases. When a control rod is inserted further into the core the power is reduced. When that control rod is then pulled out from the core the power is increased and more fission gases are produced in the fuel rods leading to a higher release of fission gases through a possible defect. By independently moving control rods at different positions it is in this way possible to locate in what part of the core the defect has appeared. Flux-tilting is however not free of risks as the method itself may lead to a higher risk of a secondary defect due to local power changes. Therefore flux-tilting should be carried out at reduced reactor power. A reduced reactor power results in a decrease of the effectiveness of the nuclear power plant and, hence, a production loss. A further way of monitoring the operation of a nuclear plant would be to use the information available from a system that continuously calculates the power distribution in the core of the reactor. The calculations could be made by advanced computer programs that use a number of measured process parameters obtained from the core. Such calculations may result in three dimensional power distribution patterns showing power peaks and power depressions for different positions of the core. The system would render it possible to make comparisons over time in order to observe where changes in the power take place. It is possible to infer the location of a defect on a fuel rod by observing these power changes, but some defects on the fuel rods appear without any prior change in the fuel assembly output power, such as those caused by mechanical wear. A purpose of the present invention is to provide improved monitoring of the operation of a reactor of a nuclear plant in order to find out if a defect on any of the fuel rods has appeared, and to localize the defect, and to find a position of the fuel assembly comprising the fuel rod comprising the defect. A method for accomplishing this comprises combining the release of fission gases and the established power distribution pattern, and observing correlations between changes in the release of fission gases and in the power distribution pattern in order to determine a position of the defect on the cladding of any of the fuel rods. The method of the present invention can include combining data from a system for detecting the release of fission gases and data from a system that establishes a power distribution pattern to find a position of a possible defect on a fuel rod in the reactor. The method finds use during the normal operation of the nuclear plant and at its normal given total reactor power. Accordingly, no reduction of power is necessary to perform the method and, hence, no production loss is experienced during the normal operation and the performance of the method. With information obtained from the method several preventive actions may be taken to reduce the risk for a discovered primary defect to develop into a secondary defect. These actions may involve a power reduction or an unchanged power in the part of the reactor where the defect is found, without the need for a flux-tilting test. It is also possible to perform a reduced flux-tilting test in the part of the reactor where the defect is most likely to be found. Furthermore, the information may be used to perform a flux-tilting test at a normal given total reactor power but with a reduced movement of the control rods, leading to a lower production loss compared to a flux-tilting test performed at reduced power. Preferably, the correlations comprise local changes in the power distribution pattern followed by a release of fission gases. Preferably, the correlations comprise local changes in the power distribution pattern followed by an increase in an on-going release of fission gases. E.g. a local power increase followed by a substantially immediate release of fission gas is a correlation which may indicate a defect in the area of the local power increase. Preferably, the plant comprises a core simulator which calculates local power levels at different positions in the core, the calculated local power levels being used to establish the instantaneous power distributions and the power distribution pattern. Preferably, the calculated local power levels are calculated by simulation models, the simulation models using core input signals comprising power affecting factors. Preferably, the power affecting factors comprise process parameters including the given total reactor power, the flow of the coolant and the temperature of the coolant at least in one position of the reactor. Preferably, local power levels are sensed by means of sensors at different positions in the core. Preferably, the sensed local power levels are compared to the calculated local power levels, whereby a recalculation and correction of the power distribution pattern is performed to establish a corrected power distribution pattern if the sensed local power levels and the calculated local power levels do not correspond. Preferably, each sensor comprises a local power range monitor or an equivalent device. The local power range monitor can periodically be calibrated by a traverse incore probe or an equivalent device. Preferably, the sensors regularly measure at least one of a local neutron flux and a local gamma flux. The present invention is also directed in one aspect to a monitoring device comprising; at least one first detector configured to measure continuously, during the normal fuel operation cycle, a radioactivity level in the off-gas stream in order to detect a possible release of fission gases from the fuel rods as a consequence of a fuel leakage due to a defect on the cladding of any of the fuel rods; a core simulator configured to establish regularly an instantaneous power distribution in the core during the normal fuel operation cycle, and to establish a power distribution pattern based on the instantaneous power distributions over time during the normal fuel operation cycle, and a processor configured to determine a position of the fuel assembly comprising the defect on the cladding of any of its fuel rods by combining the release of fission gases and the established power distribution pattern and by observing correlations between changes in the release of fission gases and the power distribution pattern. According to an embodiment of the invention, the core simulator is configured to calculate local power levels at different positions in the core and to establish the power distribution pattern based on the calculated local power levels. According to another embodiment, the monitoring device comprises sensors provided at different positions in the core and configured to sense local power levels at different positions in the core. According to a further embodiment, the monitoring device comprises a comparator configured to compare the sensed local power levels to the calculated local power levels, whereby the core simulator is configured to recalculate and correct the power distribution pattern to establish a corrected power distribution pattern if the sensed local power levels and the calculated local power levels do not correspond. According to a further embodiment, each sensor comprises a local power range monitor. The local power range monitor can periodically be calibrated by a traverse incore probe. According to a further embodiment, the sensors are configured to measure regularly at least one of a local neutron flux and a local gamma flux. An embodiment of a nuclear reactor to be monitored by the method according to the invention will first be described with reference to FIG. 1. The invention is applicable to light water reactors, such as a boiling water reactor, BWR, or a pressurized water reactor, PWR. FIG. 1 shows part of a nuclear plant. The nuclear plant comprises a reactor 1. The reactor 1 comprises a core 2 having a plurality of fuel assemblies 3. Each fuel assembly 3 includes a plurality of fuel rods (not shown), see FIG. 2a. The reactor 1 further comprises control rods 4. The control rods 4 are located between the fuel assemblies 3 and are connected to drive members 5. The drive members 5 are able to move the control rods 4 up and down in a vertical direction x into and out from a respective position between the fuel assemblies 3. The nuclear plant also comprises forcing means arranged to force a coolant 6 in a flow through the reactor 1 and the core 2. Furthermore, the nuclear plant comprises conveying means 7 arranged to convey an off-gas stream 8 from the coolant 6. A first detector D1 for measuring the radioactive activity in the off-gas stream 8 is located in the conveying means 7. Furthermore, a first recorder R1 is connected to the first detector D1. The first recorder R1 records, and possibly stores, the radioactive activity in the off-gas stream 8 measured by the first detector D1. The core 2 of the reactor 1 further comprises sensors S evenly distributed throughout different positions in the core 2. The sensors S, which are in-core instrumentation, sense local power levels in the core 2. Furthermore, the reactor 1 comprises various second detectors D2 localised at different positions in the core 2. The second detectors D2 measure process parameters such as the given total reactor power, the flow of the coolant and the temperature of the coolant. The process parameters are used to calculate local power levels at different positions in the core 2. FIG. 2a discloses a fuel rod 9 for the nuclear plant according to the invention. The fuel rod 9 comprises a cladding 10 and nuclear fuel pellets 11. The cladding 10 encloses the nuclear fuel pellets 11. A spring 12 holds the nuclear fuel pellets 11 in place. FIG. 2b discloses a fuel rod 9 similar to the one in FIG. 2a, with the difference that the cladding 10 has a defect 13, e.g. a primary defect. FIG. 3 is a flow chart illustrating the method of monitoring the operation of a nuclear reactor according to an example of the present invention by means of a monitoring device comprising the components disclosed in FIG. 3. It is referred to FIG. 1 for an illustration of a nuclear plant according to an embodiment of the invention. During the normal operation cycle of the nuclear plant an off-gas stream, which may contain fission gases due to a defect on the cladding of any of the fuel rods, is monitored, whereby possible fission gases are detected and measured by at least one first detector D1. The first detector D1 is configured to measure continuously a radioactivity level in the off-gas stream. The measurements are recorded by a first recorder R1. Simultaneously, sensors S, evenly distributed throughout the core 2 of the reactor 1, sense local power levels LPS at different positions of the core 2. Furthermore, a number of second detectors D2 measure process parameters such as the given total reactor power, the flow of the coolant and the temperature of the coolant. The process parameters are used by a core simulator 14 to calculate local power levels LPC at different positions in the core 2 of the reactor 1. The core simulator 14 divides each fuel assembly 3 into for example about 25 calculation nodes. Normally, a reactor in a nuclear plant of the type described for the present invention comprises about 400-900 fuel assemblies, resulting in thousands of calculation nodes. The core simulator 14 calculates local power levels LPC for each of these calculation nodes. A comparator 15 compares the sensed local power levels LPS to the calculated local power levels LPC. If the calculated local power levels LPC do not correspond to the sensed local power levels LPS, the difference between the calculated local power levels LPC and the sensed local power levels LPS is calculated. A recalculation and correction of the calculated local power levels LPC is thereafter performed by the core simulator 14. The sensors S are provided in the method and the monitoring device to sense the actual local power levels while the calculated local power levels LPC are an estimation of the actual local power levels made by the core simulator 14. The sensed local power levels LPS are used to correct the calculated local power levels LPC but the sensors S in the core 2 are few and some of them might not be operational continuously. The core simulator 14 is in contrast to this able to calculate the local power levels LPC continuously and in every calculation node of the fuel assemblies 3 of the core 2. The sensors S can advantageously be local power range monitors. When the local power levels LPC have been calculated and optionally recalculated by the core simulator, a calculator C establishes instantaneous power distributions PDI. The instantaneous power distributions PDI are recorded over time by a second recorder R2. Finally, the calculator C establishes a power distribution pattern PDP based on the recorded instantaneous power distributions PDI. The power distribution pattern PDP is advantageously illustrated in three dimensions, showing local power peaks and local power depressions and how they change over time. The instantaneous power distributions PDI are established everytime any of the above mentioned process parameters changes its value. A process parameter value change can for example take place due to a movement of one of the control rods 4. If no process parameter changes its value within a predetermined time, normally about 15 minutes, an automatic establishment of the instantaneous power distribution PDI takes place. The recordings from the measurements of the radioactivity level in the off-gas stream and the established power distribution pattern PDP are combined in a processor 16. The processor 16 is configured to determine a position for the defect 13 on the cladding 10 of any of the fuel rods 9 by combining the release of fission gases and the established power distribution pattern PDP, and by observing correlations in time between changes in the release of fission gases and the power distribution pattern PDP. According to the above, if a release of fission gases occurs due to a local power change, the information concerning where and when the local power change occurred helps in determining a position of the defect 13. If the time required for the fission gases to be transported from the core 2 to the first detector D1 is known, it is possible to search the established power distribution pattern PDP in order to find local power changes that occurred at the same time as the fission gas release. Everytime a change in the release of fission gases is recorded, a correlation to the power distribution pattern PDP is made. Normally, a number of local power changes occur at the same time as the change in the fission gas release occurs, but for each correlation a more likely position of the defect 13 can be determined. If, on the other hand, a local power change occurs due to a release of fission gases, the information concerning where and when the local power change occurred could be useful in determining if any of the sensors S sensed a local power change at the time of the detected release of fission gases. This case is also schematically shown in FIG. 3. As mentioned above, the comparator 15 compares the sensed local power levels LPS to the calculated local power levels LPC. Differences LPD between the calculated local power levels LPC and the sensed local power levels LPS are recorded by a third recorder R3. The recordings from the measurements of the radioactivity level in the off-gas stream and the recorded local power differences LPD are combined in the processor 16. The processor 16 is configured to determine a position for the defect 13 on the cladding 10 of any of the fuel rods 9 by combining the release of fission gases and the recorded local power differences LPD and by observing correlations in time between changes in the release of fission gases and changes in the recorded local power differences LPD. In particular, changes in the recorded local power differences LPD that do not correspond to any changes in the reactor environment are further investigated in order to determine the position for the defect 13. The method and the monitoring device aim at determining the position of a defect. As stated herein, the determination is at least partly based on a calculation, which means that the determined position will be the most likely position of the defect achievable by the established power distribution pattern and the release of fission gases. It is to be noted that the position could be the position of the fuel assembly 3 comprising the fuel rod 9 comprising the defect 13, the position of the fuel rod 9 comprising the defect 13 or the position of the defect 13 itself. The present invention is not limited to the shown embodiments but can be varied and modified within the scope of the following claims.
	claims	1. A method of determining a revision of a test suite of a model-based diagnostic testing system comprising:evaluating a diagnostic efficacy of the test suite using a probability of one or both of a correct diagnosis and an incorrect diagnosis by the test suite, wherein evaluating comprises:suggesting a test to add to the test suite to adjust an overall test coverage of the test suite, wherein suggesting a test to add comprises:creating a simulation database of the test suite;determining a probability of a correct diagnosis and a probability of an incorrect diagnosis for the test suite using the database; andcreating a list of suggested tests from the determined probabilities; andidentifying a test to delete from the test suite that comprises:determining a probability of a correct diagnosis for a modified test suite using the database, the modified test suite having a selected test removed from the test suite;computing an efficacy value associated with the selected test using the determined probabilities of a correct diagnosis for the test suite and the modified test suite; andgenerating a list of deletable tests and associated efficacy values. 2. The method of claim 1, wherein each suggested test on the list comprises a test coverage. 3. A method of determining a revision of a test suite of a model-based diagnostic testing system comprising:evaluating a diagnostic efficacy of the test suite using a probability of one or both of a correct diagnosis and an incorrect diagnosis by the test suite, wherein evaluating comprises:identifying a test to delete from the test suite, the deletable test having a minimal effect on an overall diagnostic efficacy of the test suite, wherein identifying a test comprises:creating a simulation database of the test suite;determining a probability of a correct diagnosis for the test suite using the database;determining a probability of a correct diagnosis for a modified test suite using the database, wherein the modified test suite is the test suite having a selected test removed;computing an efficacy value for the modified test suite using the determined probabilities; andgenerating a list of deletable tests using the computed efficacy values. 4. The method of claim 3, wherein determining a probability for a modified test suite is repeated for a plurality of modified test suites, each modified test suite of the plurality being the test suite having a different selected test removed. 5. The method of claim 4, wherein the selected test associated with the modified test suite having a low computed efficacy value relative to other modified test suites is the deletable test. 6. The method of claim 3, wherein evaluating further comprises:suggesting a test to add to the test suite to adjust an overall test coverage of the test suite that comprises;determining a probability of an incorrect diagnosis for the test suite using the database; andcreating a list of tests to add from the determined correct and incorrect probabilities for the test suite. 7. A method of evaluating a diagnostic efficacy of a test suite of a model-based diagnostic testing system comprising:creating a simulation database of the test suite;determining a probability of one or both of a correct diagnosis and an incorrect diagnosis for the test suite using the database; andusing the determined probability to evaluate the test suite, wherein creating a simulation database comprises:simulating an application of the test suite to a device under test, the device under test comprising one or more components; andrecording a probable result of the application in the simulation database, the simulation database being represented by a table having a plurality of columns and a plurality of rows, the plurality of columns comprising a component pattern, a test result pattern, and a number of occurrences,wherein the component pattern encodes which component is good or bad, each component of the device under test being represented by a unique position number within the component pattern,wherein the test result pattern encodes which of the tests of the test suite failed or passed, each test in the test suite being represented by a unique position within the test result pattern,wherein the number of occurrences represents a number of times that a given combination of the component pattern and the test result pattern occurred during a simulation, the number of occurrences being an integer greater than or equal to zero, andwherein each row of the plurality of rows corresponds to a different unique pattern of good and bad components. 8. The method of claim 7, wherein determining a probability of one or both of a correct diagnosis and an incorrect diagnosis comprises:copying to a database copy only those rows of the created simulation database with only one bad component in the component pattern column, all other components in the respective row being good;sorting the database copy based on the test pattern column, such that the rows with a given test pattern are adjacent to one another, the adjacent rows forming a group of rows;examining each group of rows to locate a row within each group having a largest number of occurrences relative to other rows within the respective group; andassigning a diagnosis d to each group, the diagnosis d being the position number of the bad component for the located row. 9. The method of claim 8, wherein determining a probability of one or both of a correct diagnosis and an incorrect diagnosis further comprises creating and initializing a matrix M such that matrix elements M(i,j) of the matrix M are equal to zero for all i and j, where i is an integer that ranges from one to m+1 and where j is an integer that ranges from one to m, where in is the number of tests in the test suite. 10. The method of claim 9, wherein for each group having a test pattern that represents no failed tests, determining a probability further comprises:adding iteratively for each row r in the group the number of occurrences value of the row r to a current value of the matrix element M(m+1, b) to generate a next value of the matrix element M(m+1, b), where b is a position number of the bad component for the row r. 11. The method of claim 10, wherein for each group having a test pattern that represents at least one failed test, determining a probability further comprises:adding iteratively for each row r in the group the number of occurrences value of the row r to a current value of the matrix element M(d, b) to generate a next value of the matrix element M(d, b). 12. The method of claim 11, wherein the determined probability of a correct diagnosis Pcorr is calculated usingPcorr=Σ/Ewhere Σ is a sum of diagonal elements M(i, i) of the matrix M for i equals one to m and E is a sum of all number of occurrence values in the database copy. 13. The method of claim 12, wherein using the determined probability to evaluate the test suite comprises:suggesting a test to add to the test suite to improve diagnostic efficacy. 14. The method of claim 13, wherein suggesting a test comprises:finding a relatively largest value element M(i,j) in the matrix M, where i is not equal to j, the element M(i,j) representing the probability of incorrectly diagnosing component i as the bad component when component j is actually bad; andsuggesting a test t having high coverage for component i and one of either low coverage for component j, if j is not equal to m+1, or coverage being irrelevant, if j is equal to m+1. 15. The method of claim 14, wherein suggesting a test further comprises creating a list of suggested tests, wherein creating a list comprises:repeating finding and suggesting for each element of a set of largest value elements M(i,j), a test being suggested for each element of the set of elements M(i,j); and computing a score for each of the suggested tests, the score being computed by dividing the element value M(i,j) by the total accumulated number of occurrences E. 16. The method of claim 15, wherein the list of suggested tests is represented in one or both of human readable form or machine-readable form. 17. The method of claim 12, wherein using the determined probability to evaluate the test suite comprises:identifying a test of the test suite that may be deleted front the test suite. 18. The method of claim 17, wherein for identifying a test t to delete from the test suite, the method further comprises:determining a probability of a correct diagnosis Pcorr,t for a modified test suite using the database, the modified test suite having a selected test t removed from the test suite;computing an efficacy value for the modified test suite using the determined probabilities for the test suite and for the modified test suite; andgenerating a list of deletable tests, the deletable tests having a lowest associated efficacy relative to efficacies of other tests in the test suite. 19. The method of claim 18, wherein determining a probability of a correct diagnosis Pcorr,t for a modified test suite associated with each of the tests t in the test suite comprises using a modified database created from the database copy, wherein the modified database is created comprising:copying the database copy into another database copy;selecting a test t to remove from the test suite;deleting a position from each test pattern associated with the selected test t from the other database copy; andcopying rows of the other database copy into a modified database, such that any rows that have identical values for the component pattern and the test pattern are combined together in the modified database,wherein in each row of the modified database that represents a set of combined rows from the other database copy the number of occurrences is a sum of the number of occurrence values for the combined rows. 20. The method of claim 19, wherein the probability of a correct diagnosis Pcorr,t for each of the modified test suites is determined in a manner analogous to determining the probability of a correct diagnosis Pcorr for the test suite. 21. The method of claim 19, wherein determining a probability of a correct diagnosis Pcorr,t for the modified test suite T′ using the modified database comprises:summing a largest number of occurrences value vmax found for each unique test pattern value within the modified database; anddividing the vmax sum by a total number of occurrences Et, where the total number of occurrences Et, is the sum of all numbers of occurrences in the modified database. 22. The method of claim 18, wherein computing an efficacy value for each of the tests in the test suite comprises computing a difference between the determined probability of a correct diagnosis Pcorr,t for the modified test suite corresponding to a selected test t and the determined probability of a correct diagnosis Pcorr for the test suite. 23. The method of claim 22, wherein the computed efficacy ε(t) value further comprises a cost metric c(t) associated with the test t, where ε(t)=c(t)·(Pcorr,t−Pcorr). 24. The method of claim 22, wherein the generated list of deletable tests comprises an associated efficacy value for each of the deletable tests. 25. The method of claim 18, wherein the generated list is represented in one or both of human readable form and in machine-readable form. 26. The method of claim 7, wherein the created simulation database comprises a Monte Carlo simulation of a model of the device under test. 27. A system that determines efficacy of a test suite of a model-based diagnostic testing system comprising:a processor;a memory; anda computer program stored in the memory and executed by the processor, wherein the computer program comprises instructions that, when executed by the processor, implement evaluating the test suite using a probability of one or both of a correct diagnosis and an incorrect diagnosis by the test suite to determine the efficacy, wherein the instructions that implement evaluating the test suite implement;creating a simulation database of the test suite;determining a probability of one or both of a correct diagnosis and an incorrect diagnosis using the database;using the determined probability to evaluate the test suite; anddetermining a probability of a correct diagnosis for a modified test suite using the database, the modified test suite having a selected test removed from the test suite;and wherein using the determined probability comprises;computing an efficacy value for the modified test suite using the determined probability of a correct diagnosis for both the test suite and the modified test suite; andgenerating a list of tests to delete from the test suite based on the computed efficacy value. 28. The system of claim 27, wherein using the determined probability of both a correct diagnosis and an incorrect diagnosis comprises creating a list of suggested tests to add to the test suite, each suggested test having an associated test coverage. 29. The system of claim 27, wherein determining a probability of a correct diagnosis for a modified test suite is repeated for different modified test suites, each different modified test suite having an associated different selected test being removed. 30. A system that determines efficacy of a test suite of a model-based diagnostic testing system comprising:a processor;a memory; anda computer program stored in the memory and executed by the processor, wherein the computer program comprises instructions that, when executed by the processor, implement evaluating the test suite using a probability of one or both of a correct diagnosis and an incorrect diagnosis by the test suite to determine the efficacy, wherein the instructions that implement evaluating the test suite implement one or both of suggesting a test to add to the test suite and identifying a test to delete from the test suite, wherein suggesting a test to add to the test suite and identifying a test to delete from the test suite each comprise a list of respective tests, the lists being represented in one or both of human readable form and machine-readable form.
	abstract	An interferometer is disclosed which has upper-stage, intermediate-stage, and lower-stage electron biprisms. The disclosed interferometer operates with an azimuth angle Φ among filament electrodes of the three electron biprisms to arbitrarily control an interference area and an azimuth θ of the interference fringes formed therein, eliminates Fresnel fringes generation, and allows independent control of an interference fringe spacing s and the azimuth θ of the interference fringes.
056298722	description	DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS In a method of the invention signals from industrial process sensors can be used to modify or terminate degrading or anomalous processes. The sensor signals are manipulated to provide input data to a statistical analysis technique, such as a process entitled Spectrum Transformed Sequential Testing ("SPRT"). Details of this process and the invention therein are disclosed in U.S. patent application Ser. No. 07/827,776 filed Jan. 29, 1992 now U.S. Pat. No. 5,223,207 which is incorporated by reference herein in its entirety. A further illustration of the use of SPRT for analysis of data bases is set forth in the copending application filed contemporaneously, entitled "Processing Data Base Information Having Nonwhite Noise," also incorporated by reference herein in its entirety. The procedures followed in a preferred method are shown generally in FIG. 8. In performing such a preferred analysis of the sensor signals, a dual transformation method is performed, insofar as it entails both a frequency-domain transformation of the original time-series data and a subsequent time-domain transformation of the resultant data. The data stream that passes through the dual frequency-domain, time-domain transformation is then processed with the SPRT procedure, which uses a log-likelihood ratio test. A computer software appendix is also attached hereto covering the SPRT procedure and its implementation in the context of, and modified by, the instant invention. In the preferred embodiment, successive data observations are performed on a discrete process Y, which represents a comparison of the stochastic components of physical processes monitored by a sensor, and most preferably pairs of sensors. In practice, the Y function is obtained by simply differencing the digitized signals from two respective sensors. Let Y.sub.k represent a sample from the process Y at time t.sub.k. During normal operation with an undegraded physical system and with sensors that are functioning within specifications the Y.sub.k should be normally distributed with mean of zero. Note that if the two signals being compared do not have the same nominal mean values (due, for example, to differences in calibration), then the input signals will be pre-normalized to the same nominal mean values during initial operation. In performing the monitoring of industrial processes, the system's purpose is to declare a first system or a second system degraded if the drift in Y is sufficiently large that the sequence of observations appears to be distributed about a mean +M or -M, where M is our pre-assigned system-disturbance magnitude. We would like to devise a quantitative framework that enables us to decide between two hypotheses, namely: H.sub.1 : Y is drawn from a Gaussian probability distribution function ("PDF") with mean M and variance .sigma..sup.2. PA1 H.sub.2 : Y is drawn from a Gaussian PDF with mean 0 and variance .sigma..sup.2. We will suppose that if H.sub.1 or H.sub.2 is true, we wish to decide for H.sub.1 or H.sub.2 with probability (1-.beta.) or (1-.alpha.), respectively, where .alpha. and .beta. represent the error (misidentification) probabilities. From the conventional, well known theory of Wald, the test depends on the likelihood ratio 1.sub.n, where ##EQU1## After "n" observations have been made, the sequential probability ratio is just the product of the probability ratios for each step: ##EQU2## where f(y.vertline.H) is the distribution of the random variable y. Wald's theory operates as follows: Continue sampling as long as A<l.sub.n <B. Stop sampling and decide H.sub.1 as soon as l.sub.n .gtoreq.B, and stop sampling and decide H.sub.2 as soon as l.sub.n .ltoreq.A. The acceptance thresholds are related to the error (misidentification) probabilities by the following expressions: ##EQU3## The (user specified) value of .alpha. is the probability of accepting H.sub.1 when H.sub.2 is true (false alarm probability). .beta. is the probability of accepting H.sub.2 when H.sub.1 is true (missed alarm probability). If we can assume that the random variable Y.sub.k is normally distributed, then the likelihood that H.sub.1 is true (i.e., mean M, variance .sigma..sup.2) is given by: ##EQU4## Similarly for H.sub.2 (mean 0, variance .sigma..sup.2): ##EQU5## The ratio of (5) and (6) gives the likelihood ratio 1.sub.n ##EQU6## Combining (4) and (7), and taking natural logs gives ##EQU7## Our sequential sampling and decision strategy can be concisely represented as: ##EQU8## Following Wald's sequential analysis, it is conventional that a decision test based on the log likelihood ratio has an optimal property; that is, for given probabilities .alpha. and .beta. there is no other procedure with at least as low error probabilities or expected risk and with shorter length average sampling time. A primary limitation that has heretofore precluded the applicability of Wald-type binary hypothesis tests for sensor and equipment surveillance strategies lies in the primary assumption upon which Wald's theory is predicated; i.e, that the original process Y is strictly "white" noise, independently-distributed random data. Such white noise can, for example, include Gaussian noise. It is, however, very rare to find physical process variables associated with operating machinery that are not contaminated with serially-correlated, deterministic noise components. Such serially correlated noise components includes, for example, auto-correlated and Markov dependent noise. This invention can overcome this limitation to conventional surveillance strategies by integrating the Wald sequential-test approach with a new dual transformation technique. This symbiotic combination of frequency-domain transformations and time-domain transformations produces a tractable solution to a particularly difficult problem that has plagued signal-processing specialists for many years. In the preferred embodiment of the method shown in detail in FIG. 8, serially-correlated data signals from an industrial process can be rendered amenable to the SPRT testing methodology described hereinbefore. This is preferably done by performing a frequency-domain transformation of the original difference function Y. A particularly preferred method of such a frequency transformation is accomplished by generating a Fourier series using a set of highest "1" number of modes. Other procedures for rendering the data amenable to SPRT methods includes, for example, auto regressive techniques, which can accomplish substantially similar results described herein for Fourier analysis. In the preferred approach of Fourier analysis to determine the "1" highest modes (see FIG. 8A): ##EQU9## where a.sub.0 /2 is the mean value of the series, a.sub.m and b.sub.m are the Fourier coefficients corresponding to the Fourier frequency .omega..sub.m, and N is the total number of observations. Using the Fourier coefficients, we next generate a composite function, X.sub.t, using the values of the largest harmonics identified in the Fourier transformation of Y.sub.t. The following numerical approximation to the Fourier transform is useful in determining the Fourier coefficients a.sub.m and b.sub.m. Let x.sub.j be the value of X.sub.t at the jth time increment. Then assuming 2.pi. periodicity and letting .omega..sub.m =2.pi.m/N, the approximation to the Fourier transform yields: ##EQU10## for 0<m<N/2. Furthermore, the power spectral density ("PSD") function for the signal is given by 1.sub.m where ##EQU11## To keep the signal bandwidth as narrow as possible without distorting the PSD, no spectral windows or smoothing are used in our implementation of the frequency-domain transformation. In analysis of a pumping system of the EBR-II reactor of Argonne National Laboratory, the Fourier modes corresponding to the eight highest 1.sub.m, provide the amplitudes and frequencies contained in X.sub.t. In our investigations for the particular pumping system data taken, the highest eight 1.sub.m modes were found to give an accurate reconstruction of X.sub.t while reducing most of the serial correlation for the physical variables we have studied. In other industrial processes, the analysis could result in more or fewer modes being needed to accurately construct the functional behavior of a composite curve. Therefore, the number of modes used is a variable which is iterated to minimize the degree of nonwhite noise for any given application. As noted in FIG. 8A a variety of noise tests are applied in order to remove serially correlated noise. The reconstruction of X.sub.t uses the general form of Eqn. (12), where the coefficients and frequencies employed are those associated with the eight highest PSD values. This yields a Fourier composite curve (see end of flowchart in FIG. A) with essentially the same correlation structure and the same mean as Y.sub.t. Finally, we generate a discrete residual function R.sub.t by differencing corresponding values of Y.sub.t and X.sub.t. This residual function, which is substantially devoid of serially correlated contamination, is then processed with the SPRT technique described hereinbefore. In a specific example application of the above referenced methodology, certain variables were monitored from the Argonne National Laboratory reactor EBR-II. In particular, EBR-II reactor coolant pumps (RCPs) and delayed neutron (DN) monitoring systems were tested continuously to demonstrate the power and utility of the invention. The RCP and DN systems were chosen for initial application of the approach because SPRT-based techniques have already been under development for both the systems. All data used in this investigation were recorded during full-power, steady state operation at EBR-II. The data have been digitized at a 2-per-second sampling rate using 2.sup.14 (16,384) observations for each signal of interest. FIGS. 1-3 illustrate data associated with the preferred spectral filtering approach as applied to the EBR-II primary pump power signal, which measures the power (in kW) needed to operate the pump. The basic procedure of FIG. 8 was then followed in the analysis. FIG. 1 shows 136 minutes of the original signal as it was digitized at the 2-Hz sampling rate. FIG. 2 shows a Fourier composite constructed from the eight most prominent harmonics identified in the original signal. The residual function, obtained by subtracting the Fourier composite curve from the raw data, is shown in FIG. 3. Periodograms of the raw signal and the residual function have been computed and are plotted in FIG. 4. Note the presence of eight depressions in the periodogram of the residual function in FIG. 4B, corresponding to the most prominent periodicities in the original, unfiltered data. Histograms computed from the raw signal and the residual function are plotted in FIG. 5. For each histogram shown we have superimposed a Gaussian curve (solid line) computed from a purely Gaussian distribution having the same mean and variance. Comparison of FIG. 5A and 5B provide a clear demonstration of the effectiveness of the spectral filtering in reducing asymmetry in the histogram. Quantitatively, this decreased asymmetry is reflected in a decrease in the skewness (or third moment of the noise) from 0.15 (raw signal) to 0.10 (residual function). It should be noted here that selective spectral filtering, which we have designed to reduce the consequences of serial correlation in our sequential testing scheme, does not require that the degree of nonnormality in the data will also be reduced. For many of the signals we have investigated at EBR-II, the reduction in serial correlation is, however, accompanied by a reduction in the absolute value of the skewness for the residual function. To quantitatively evaluate the improvement in whiteness effected by the spectral filtering method, we employ the conventional Fisher Kappa white noise test. For each time series we compute the Fisher Kappa statistic from the defining equation ##EQU12## where 1(.omega..sub.k) is the PSD function (see Eq. 14) at discrete frequencies .omega..sub.k, and 1(L) signifies the largest PSD ordinate identified in the stationary time series. The Kappa statistic is the ratio of the largest PSD ordinate for the signal to the average ordinate for a PSD computed from a signal contaminated with pure white noise. For EBR-II the power signal for the pump used in the present example has a .kappa. of 1940 and 68.7 for the raw signal and the residual function, respectively. Thus, we can say that the spectral filtering procedure has reduced the degree of nonwhiteness in the signal by a factor of 28. Strictly speaking, the residual function is still not a pure white noise process. The 95% critical value for Kappa for a time series with 2.sup.14 observations is 12.6. This means that only for computed Kappa statistics lower than 12.6 could we accept the null hypothesis that the signal is contaminated by pure white noise. The fact that our residual function is not purely white is reasonable on a physical basis because the complex interplay of mechanisms that influence the stochastic components of a physical process would not be expected to have a purely white correlation structure. The important point, however, is that the reduction in nonwhiteness effected by the spectral filtering procedure using only the highest eight harmonics in the raw signal has been found to preserve the pre-specified false alarm and missed alarm probabilities in the SPRT sequential testing procedure (see below). Table I summarizes the computed Fisher Kappa statistics for thirteen EBR-II plant signals that are used in the subject surveillance systems. In every case the table shows a substantial improvement in signal whiteness. The complete SPRT technique integrates the spectral decomposition and filtering process steps described hereinbefore with the known SPRT binary hypothesis procedure. The process can be illustratively demonstrated by application of the SPRT technique to two redundant delayed neutron detectors (designated DND A and DND B) whose signals were archived during long-term normal (i.,e., undegraded) operation with a steady DN source in EBR-II. For demonstration purposes a SPRT was designed with a false alarm rate, .alpha., of 0.01. Although this value is higher than we would designate for a production surveillance system, it gives a reasonable frequency of false alarms so that asymptotic values of .alpha. can be obtained with only tens of thousands of discrete observations. According to the theory of the SPRT technique, it can be easily proved that for pure white noise (such as Gaussian), independently distributed processes, .alpha. ct provides an upper bound to the probability (per observation interval) of obtaining a false alarm--i.e., obtaining a "data disturbance" annunciation when, in fact, the signals under surveillance are undegraded. FIGS. 6 and 7 illustrate sequences of SPRT results for raw DND signals and for spectrally-whitened DND signals, respectively. In FIGS. 6A and 6B, and 7A and 7B, respectively, are shown the DN signals from detectors DND-A and DND-B. The steady-state values of the signals have been normalized to zero. TABLE I ______________________________________ Effectiveness of Spectral Filtering for Measured Plant Signals Fisher Kappa Test Statistic (N = 16,384) Plant Variable I.D. Raw Signal Residual Function ______________________________________ Pump 1 Power 1940 68.7 Pump 2 Power 366 52.2 Pump 1 Speed 181 25.6 Pump 2 Speed 299 30.9 Pump 1 Radial Vibr (top) 123 67.7 Pump 2 Radial Vibr (top) 155 65.4 Pump 1 Radial Vibr (bottom) 1520 290.0 Pump 2 Radial Vibr (bottom) 1694 80.1 DN Monitor A 96 39.4 DN Monitor B 81 44.9 DN Detector 1 86 36.0 DN Detector 2 149 44.1 DN Detector 3 13 8.2 ______________________________________ Normalization to adjust for differences in calibration factor or viewing geometry for redundant sensors does not affect the operability of the SPRT. FIGS. 6C and 7C in each figure show pointwise differences of signals DND-A and DND-B. It is this difference function that is input to the SPRT technique. Output from the SPRT method is shown for a 250-second segment in FIGS. 6D and 7D. Interpretation of the SPRT output in FIGS. 6D and 7D is as follows: When the SPRT index reaches a lower threshold, A, one can conclude with a 99% confidence factor that there is no degradation in the sensors. For this demonstration A is equal to 4.60, which corresponds to false-alarm and missed-alarm probabilities of 0.01. As FIGS. 6D and 7D illustrate, each time the SPRT output data reaches A, it is reset to zero and the surveillance continues. If the SPRT index drifts in the positive direction and exceeds a positive threshold, B, of +4.60, then it can be concluded with a 99% confidence factor that there is degradation in at least one of the sensors. Any triggers of the positive threshold are signified with diamond symbols in FIGS. 6D and 7D. In this case, since we can certify that the detectors were functioning properly during the time period our signals were being archived, any triggers of the positive threshold are false alarms. If we extend sufficiently the surveillance experiment illustrated in FIG. 6D, we can get an asymptotic estimate of the false alarm probability .alpha.. We have performed this exercise using 1000-observation windows, tracking the frequency of false alarm trips in each window, then repeating the procedure for a total of sixteen independent windows to get an estimate of the variance on this procedure for evaluating . The resulting false-alarm frequency for the raw, unfiltered, signals is .alpha.=0.07330 with a variance of 0.000075. The very small variance shows that there would be only a negligible improvement in our estimate by extending the experiment to longer data streams. This value of .alpha. is significantly higher than the design value of .alpha.=0.01, and illustrates the danger of blindly applying a SPRT test technique to signals that may be contaminated by excessive serial correlation. The data output shown in FIG. 7D employs the complete SPRT technique shown schematically in FIG. 8. When we repeat the foregoing exercise using 16 independent 1000-observation windows, we obtain an asymptotic cumulative false-alarm frequency of 0.009142 with a variance of 0.000036. This is less than (i.e., more conservative than) the design value of .alpha.=0.01, as desired. It will be recalled from the description hereinbefore regarding one preferred embodiment, we have used the eight most prominent harmonics in the spectral filtration stage of the SPRT technique. By repeating the foregoing empirical procedure for evaluating the asymptotic values of .alpha., we have found that eight modes are sufficient for the input variables shown in Table I. Furthermore, by simulating subtle degradation in individual signals, we have found that the presence of serial correlation in raw signals gives rise to excessive missed-alarm probabilities as well. In this case spectral whitening is equally effective in ensuring that pre-specified missed-alarm probabilities are not exceeded using the SPRT technique. In another different form of the invention, it is not necessary to have two sensor signals to form a difference function. One sensor can provide a real signal characteristic of an ongoing process and a record artificial signal can be generated to allow formation of a difference function. Techniques such as an auto regressive moving average (ARMA) methodology can be used to provide the appropriate signal, such as a DC level signal, a cyclic signal or other predictable signal. Such an ARMA method is a well-known procedure for generating artificial signal values, and this method can even be used to learn the particular cyclic nature of a process being monitored enabling construction of the artificial signal. The two signals, one a real sensor signal and the other an artificial signal, can thus be used in the same manner as described hereinbefore for two real sensor signals. The difference function Y is then formed, transformations performed and a residual function is determined which is free of serially correlated noise. Fourier techniques are very effective in achieving a whitened signal for analysis, but there are other means to achieve substantially the same results using a different analytical methodology. For example, filtration of serial correlation can be accomplished by using the autoregressive moving average (ARMA) method. This ARMA technique estimates the specific correlation structure existing between sensor points of an industrial process and utilizes this correlation estimate to effectively filter the data sample being evaluated. A technique has therefore been devised which integrates frequency-domain filtering with sequential testing methodology to provide a solution to a problem that is endemic to industrial signal surveillance. The subject invention particularly allows sensing slow degradation that evolves over a long time period (gradual decalibration bias in a sensor, appearance of a new radiation source in the presence of a noisy background signal, wear out or buildup of a radial rub in rotating machinery, etc.). The system thus can alert the operator of the incipience or onset of the disturbance long before it would be apparent to visual inspection of strip chart or CRT signal traces, and well before conventional threshold limit checks would be tripped. This permits the operator to terminate, modify or avoid events that might otherwise challenge technical specification guidelines or availability goals. Thus, in many cases the operator can schedule corrective actions (sensor replacement or recalibration; component adjustment, alignment, or rebalancing; etc.) to be performed during a scheduled system outage. Another important feature of the technique which distinguishes it from conventional methods is the built-in quantitative false-alarm and missed-alarm probabilities. This is quite important in the context of high-risk industrial processes and applications. The invention makes it possible to apply formal reliability analysis methods to an overall system comprising a network of interacting SPRT modules that are simultaneously monitoring a variety of plan variables. This amenability to formal reliability analysis methodology will, for example, greatly enhance the process of granting approval for nuclear-plant applications of the invention, a system that can potentially save a utility millions of dollars per year per reactor. While preferred embodiments of the invention have been shown and described, it will be clear to those skilled in the an that various changes and modifications can be made without departing from the invention in its broader aspects as set forth in the claims provided hereinafter.
047117591	claims	1. A removable cruciform for use in an ice basket having a generally cylindrical sidewall defining a central, vertical axis of the ice basket and plural, generally annular retaining rings secured to the interior of the cylindrical sidewall of the ice basket at predetermined, spaced elevations throughout the axial height of the ice basket, comprising: a pair of brackets, each comprising a central, base portion having parallel longitudinal edges and a pair of integral legs extending at corresponding angles relative to said base portion from the respective parallel longitudinal edges thereof; a pair of support plate assemblies secured to and extending in parallel, spaced relationship from one of said pair of brackets, generally perpendicular to said base portion thereof, each said support plate assembly defining a corresponding slide channel; a pair of slide support plates secured to the other of said pair of brackets and extending therefrom in spaced, parallel relationship, and received in telescoping, sliding relationship in the corresponding slide channels of the pair of respective support plate assemblies of said one of said brackets thereby to dispose said base portions of said pair of brackets in parallel, spaced relationship and defining therewith a housing of nominally, generally square configuration; and spring means received within said housing and engaging said base portions of said brackets and applying a resilient biasing force thereto for maintaining said spaced relationship thereof. said C-shaped spring is received within said housing of said cruciform in symmetrically disposed relationship relative to said base portions of said brackets, and further comprises a pair of notches in the upper and lower circumferential edges thereof at positions contiguous to the upper and lower lateral edges of said base portions of said brackets; and each of said base portions of said brackets further comprises a tab extending from a central portion of each of the upper and lower edges thereof, laterally inwardly with respect to said housing and received in the respectively corresponding notches of the upper and lower circumferential edges of said C-shaped spring. first and second parallel slots in each of said support plate assemblies, extending in respective, vertically displaced, laterally oriented relationship; and first and second vertically displaced pairs of pins in each of said slide support plates respectively corresponding to said first and second parallel slots and disposed therein in corresponding, laterally oriented, displaced positions, and received in the respective said first and second slots of the respective support plate assemblies to align the respective said slide support plates and support plate assemblies and permit limited, telescoping and sliding engagement thereof. said integral legs of each of said pair of brackets extend from said corresponding, central base portions at said corresponding angular relationship so as to be radially oriented relative to the cylindrical sidewall of an ice basket within which the cruciform is positioned in generally horizontal orientation; and each of said integral legs of said brackets includes means thereon for engaging a corresponding retaining ring of the ice basket when the cruciform is disposed at a corresponding, predetermined elevation at which the ring is secured to the interior sidewall of the ice basket. a pair of brackets, each comprising a central, base portion having parallel longitudinal edges and a pair of integral legs extending at corresponding angles relative to said base portion from the respective parallel longitudinal edges thereof; a pair of support plate assemblies secured to and extending in parallel, spaced relationship from one of said pair of brackets, generally perpendicular to said base portion thereof, each said support plate assembly defining a corresponding slide channel; a pair of slide support plates secured to the other of said pair of brackets and extending therefrom in spaced, parallel relationship, and received in telescoping, sliding relationship in the corresponding slide channels of the pair of respective support plate assemblies of said one of said brackets thereby to dispose said base portions of said pair of brackets in parallel, spaced relationship and define therewith a housing of nominally, generally square configuration; and spring means received within said housing and engaging said base portions of said brackets and applying a resilient force thereto for maintaining said spaced relationship thereof. said C-shaped spring is received within said housing of said cruciform in symmetrically disposed relationship relative to said base portions of said brackets, and further comprises a pair of notches in the upper and lower circumferential edges thereof at positions contiguous to the upper and lower lateral edges of said base portions of said brackets; and each of said base portions of said brackets further comprises a tab extending from a central portion of each of the upper and lower edges thereof, laterally, inwardly with respect to said housing and received in the respectively corresponding notches of the upper and lower circumferential edges of said C-shaped spring. first and second parallel slots in each of said support plate assemblies, extending in respective vertically displaced, laterally oriented relationship; and first and second vertically displaced pairs of pins in each of said slide support plates respectively corresponding to said first and second parallel slots and disposed therein in corresponding, laterally displaced positions, for being received in the respective said first and second slots of the respective support plate assemblies to align the respective said slide support plates and support plate assemblies and permit limited, telescoping and sliding engagement thereof. said integral legs of each of said pair of brackets extend from said corresponding, central base portions at said corresponding angular relationship so as to be radially oriented relative to the cylindrical sidewall of an ice basket within which the cruciform is positioned in generally horizontal orientation; and each of said integral legs of said brackets includes means thereon for engaging a corresponding retaining ring of the ice basket when the cruciform is disposed at a corresponding, predetermined elevation at which the ring is secure to the interior sidewall of the ice basket. 2. A removable cruciform as recited in claim 1, wherein said spring means comprises a longitudinally extending spring of generally C-shaped cross-section and having an axial height corresponding generally to the longitudinal height of said base portions of said pair of brackets. 3. A removable cruciform as recited in claim 2, wherein: 4. A removable cruciform as recited in claim 1, wherein there is further provided: 5. A removable cruciform as recited in claim 1, wherein: 6. A removable cruciform as recited in claim 5, wherein said engaging means comprise a pair of spaced feet extending integrally from the free longitudinal edge of the corresponding said leg and spaced apart so as to define therebetween a receiving channel at the free longitudinal edge of the corresponding said leg for engaging therein the annular retaining ring. 7. A nuclear reactor system having an array of ice baskets disposed thereabout, each said ice basket having a generally cylindrical sidewall and plural, annular retaining rings secured to the interior surface of the sidewall at predetermined, spaced elevations throughout the axial height of the ice basket, removable cruciforms being mounted within said ice basket at predetermined, spaced elevations therewithin displaced from the open, upper end of the ice basket and defining therewithin corresponding compartments, each to be charged with ice, each said removable cruciform, when so mounted, engaging a corresponding, annular retaining ring for supporting a charge of ice received in the corresponding compartment thereabove, and comprising: 8. A nuclear reactor system as recited in claim 7, wherein said spring means comprises a longitudinally extending spring of generally C-shaped cross-section and having an axial height corresponding generally to the longitudinal height of said base portions of said pair of brackets. 9. A nuclear reactor system as recited in claim 8, wherein: 10. A nuclear reactor system as recited in claim 7, wherein there is further provided: 11. A nuclear reactor system as recited in claim 7, wherein: 12. A nuclear reactor system as recited in claim 6, wherein said engaging means comprise a pair of spaced feet extending integrally from the free longitudinal edge of the corresponding said leg and spaced apart so as to define therebetween a receiving channel at the free longitudinal edge of the corresponding said leg for engaging therein the annular retaining ring.
	summary
	claims	1. A maintenance system that calculates a timing to make a visit for maintenance work of consumable parts of a machine to be maintained; the system comprising:a visit-interval calculating section for calculating a visit interval to make a visit for maintenance work for each consumable part on the basis of a failure rate distribution;a replacement-interval calculating section that calculates a replacement interval to replace the consumable parts for each consumable part on the basis of the failure rate distribution; anda visit-timing calculating section that calculates a timing to actually visit the machine to be maintained on the basis of the visit interval calculated by the visit-interval calculating section and the replacement interval calculated by the replacement-interval calculating section. 2. The maintenance system according to claim 1, further comprising:a failure-rate-distribution calculating section that calculates the failure rate distribution of each consumable part on the basis of maintenance historical data, that is, history information on maintenance work performed for the machine to be maintained, whereinthe visit-interval calculating section calculates the visit interval to make a visit for maintenance work for each consumable part on the basis of the failure rate distribution calculated by the failure-rate-distribution calculating section and the maintenance historical data; andthe replacement-interval calculating section calculates the replacement interval to replace the consumable parts for each consumable part on the basis of the failure rate distribution calculated by the failure-rate-distribution calculating section and the maintenance historical data. 3. The maintenance system according to claim 1, wherein:the visit-interval calculating section calculates the visit interval at random, and the replacement-interval calculating section calculates the replacement interval at random; andthe visit-timing calculating section obtains a combination of a visit interval and a replacement interval in which a predetermined cost is the minimum, on the basis of the visit interval calculated by the visit-interval calculating section and the replacement interval calculated by the replacement-interval calculating section. 4. The maintenance system according to claim 3, whereinthe visit interval calculated for each consumable part by the visit-interval calculating section is set longer than the replacement interval calculated by the replacement-interval calculating section. 5. The maintenance system according to claim 3, whereinthe predetermined cost is the sum of labor costs for the maintenance work by a serviceman, material costs for the consumable parts, and the loss due to the reason that the user cannot use the machine to be maintained. 6. The maintenance system according to claim 1, whereinthe visit-timing calculating section obtains a combination of a visit interval and a replacement interval in which a predetermined cost is the minimum by search processing using a Monte Carlo method or a generic algorithm on the basis of the visit interval calculated by the visit-interval calculating section and the replacement interval calculated by the replacement-interval calculating section. 7. The maintenance system according to claim 1, whereinthe visit-timing calculating section calculates a list of a next visit timing and consumable parts to be replaced at the next visit timing on the basis of the visit interval calculated by the visit-interval calculating section and the replacement interval calculated by the replacement-interval calculating section. 8. The maintenance system according to claim 1, whereinthe visit-interval calculating section and the replacement-interval calculating section calculate values close to intervals at which the failure rate is estimated to be higher than a predetermined rate, on the basis of the failure rate distribution of each consumable part, which is calculated by the failure-rate-distribution calculating section. 9. A maintenance method for calculating a timing to make a visit for maintenance work of consumable parts of a machine to be maintained, the method comprising:a failure-rate-distribution calculating step of calculating the failure rate distribution of each consumable part on the basis of maintenance historical data, that is, history information on maintenance work performed for the machine to be maintained;a visit-interval calculating step of calculating a visit interval to make a visit for maintenance work for each consumable part on the basis of the failure rate distribution calculated in the failure-rate-distribution calculating step and the maintenance historical data;a replacement-interval calculating step of calculating a replacement interval to replace the consumable parts for each consumable part on the basis of the failure rate distribution calculating in the failure-rate-distribution calculating step and the maintenance historical data; anda visit-timing calculating step of calculating a timing to actually visit the machine to be maintained on the basis of the visit interval calculated in the visit-interval calculating step and the replacement interval calculated in the replacement-interval calculating step. 10. The maintenance method according to claim 9, whereinin the visit-interval calculating step, the visit interval is calculated at random, and in the replacement-interval calculating step, the replacement interval is calculated at random; andin the visit-timing calculating step, a combination of a visit interval and a replacement interval in which a predetermined cost is the minimum is obtained on the basis of the visit interval calculated in the visit-interval calculating step and the replacement interval calculated in the replacement-interval calculating step. 11. The maintenance method according to claim 10, whereinthe predetermined cost is the sum of labor costs for the maintenance work by a serviceman, material costs for the consumable parts, and the loss due to the reason that the user cannot use the machine to be maintained. 12. The maintenance method according to claim 10, whereinin the visit-timing calculating step, a combination of a combination of a visit interval and a replacement interval in which a predetermined cost is the minimum is obtained by search processing using a Monte Carlo method or a generic algorithm on the basis of the visit interval calculated in the visit-interval calculating step and the replacement interval calculated in the replacement-interval calculating step. 13. The maintenance method according to claim 9, whereinin the visit-timing calculating step, a list of a next visit timing and consumable parts to be replaced at the next visit timing is calculated on the basis of the visit interval calculated in the visit-interval calculating step and the replacement interval calculated in the replacement-interval calculating step. 14. The maintenance method according to claim 9, whereinin the visit-timing calculating step and the replacement-interval calculating step, values close to intervals at which the failure rate is estimated to be higher than a predetermined rate are calculated on the basis of the failure rate distribution of each consumable part, which is calculated in the failure-rate-distribution calculating step. 15. A computer-readable storage medium storing a maintenance program for a computer to execute a process of calculating a timing to make a visit for maintenance work for consumable parts of a machine to be maintained, the maintenance program including instructions which, when executed, cause the computer to perform actions comprising:a failure-rate-distribution calculating step of calculating the failure rate distribution of each consumable part on the basis of maintenance historical data, that is, history information on maintenance work performed for the machine to be maintained;a visit-interval calculating step of calculating a visit interval to make a visit for maintenance work for each consumable part on the basis of the failure rate distribution calculated in the failure-rate-distribution calculating step and the maintenance historical data;a replacement-interval calculating step of calculating a replacement interval to replace the consumable parts for each consumable part on the basis of the failure rate distribution calculated in the failure-rate-distribution calculating step and the maintenance historical data; anda visit-timing calculating step of calculating a timing to actually visit the machine to be maintained on the basis of the visit interval calculated in the visit-interval calculating step and the replacement interval calculated in the replacement-interval calculating step. 16. The computer-readable storage medium according to claim 15, whereinin the visit-interval calculating step, the visit interval is calculated at random, and in the replacement-interval calculating step, the replacement interval is calculated at random; andin the visit-timing calculating step, a combination of a visit interval and a replacement interval in which a predetermined cost is the minimum is obtained on the basis of the visit interval calculated in the visit-interval calculating step and the replacement interval calculated in the replacement-interval calculating step. 17. The computer-readable storage medium according to claim 16, whereinthe visit interval calculated for each consumable part in the visit-interval calculating step is set longer than the replacement interval calculated in the replacement-interval calculating step. 18. The computer-readable storage medium according to claim 16, whereinthe predetermined cost is the sum of labor costs for the maintenance work by a serviceman, material costs for the consumable parts, and the loss due to the reason that the user cannot use the machine to be maintained. 19. The computer-readable storage medium according to claim 16, whereinin the visit-timing calculating step, a combination of a visit interval and a replacement interval in which a predetermined cost is the minimum is obtained by search processing using a Monte Carlo method or a generic algorithm on the basis of the visit interval calculated in the visit-interval calculating step and the replacement interval calculated in the replacement-interval calculating step. 20. The computer-readable storage medium according to claim 15, whereinin the visit-timing calculating step, a list of a next visit timing and consumable parts to be replaced at the next visit timing is calculated on the basis of the visit interval calculated in the visit-interval calculating step and the replacement interval calculated in the replacement-interval calculating step.
053176138	summary	This invention relates to a boiling water nuclear reactor having high power density. More specifically, a fuel bundle construction is set forth in which each discrete fuel rod, consisting, for example, of a stack of fuel pellets enclosed in tubular cladding, has its very own concentric fuel channel. The fuel rods and concentric channels are preferably arrayed in a triangular matrix. A core of such fuel bundles has the characteristic that all rods uniformly approach their respective thermal limits enabling higher power density in the reactor. BACKGROUND OF THE INVENTION Problem Statement Boiling water reactor power densities have been limited in the past to less than 56 kilowatts per liter (KW/1), primarily as a result of their original designs. These designs constrain the power outputs of these reactors due to thermal limits and stability considerations. Thermal limits include the maximum linear heat generation rate and the minimum critical power ratio. The maximum linear heat generation rate (MLHGR) is that maximum amount of heat output by a lineal foot of fuel rod. Normal MLHGR rates for a boiling water nuclear reactor are in the range of 12.1 to 14.4 Kw/ft (or, 40 to 47 Kw/m using purely metric units). Simply stated, the MLHGR is a limitation established by the fuel pellet swelling establishing a mechanical interference with the cladding containing the fuel rod. The MLHGR cannot be exceeded at any individual fuel rod within a fuel bundle without potential damage to that particular fuel rod within the fuel bundle. As no individual rod is permitted to be damaged within a fuel bundle, the entire bundle is limited in its performance to maintain the maximum linear heat generation rate in any given fuel rod location. It is to be understood that to the extent a particular bundle constituting part of a reactor core is limited in its output, the entire core is likewise limited. The minimum critical power ratio (MCPR) is the ratio of that level of fuel bundle power at which some point experiences transition from nucleate to film boiling compared to the then present output of the fuel bundle. This ratio is not permitted to be less than a numerical value of one anywhere within an individual fuel bundle. If the limit were to be exceeded at any given location within the fuel bundle, the temperature of the cladding of the fuel rod would rapidly increase due to increased resistance in the heat flow path from the interior of the fuel rod to the exterior of the fuel rod. Potential failure of the particular fuel rod cladding could follow. The concept of a ratio is utilized in establishing limits of critical power within the fuel bundle. The ratio is maintained at a limit where operating conditions--both expected in normal operations and during anticipated abnormal operating occurrences or "transients"--can occur without running the risk of damage to the sealed fuel rods within the reactor. In already designed nuclear reactors, these thermal limits are largely established by the original design. There is, however, a need to increase the power output density of nuclear reactors of new manufacture. Accordingly, the factors relating to the power output densities will be briefly reviewed. Conventional fuel designs will be briefly discussed, especially insofar as they incorporate many heterogenous distributions in their neutron density and related power output. Thereafter, reference will be made to certain new reactor designs. Regarding the factors relating to increasing power densities, vessel sizes are limited in diameter to approximately seven meters, given the desire to continue to use forging to manufacture such vessels in existing manufacturing facilities capabilities. There exists a reluctance to expand vessel fabrication facilities beyond existing size limits under present market realities. Therefore, each reactor vessel is practically limited in its diameter. This requires that the number of fuel bundles within a BWR core is therefore limited. Limitations also exist in establishing the active fuel length of fuel rod bundles since as fuel rod length increases, thermal margins and stability become of concern. The longer the fuel bundle, the greater the possibility of transition boiling unless considerable additional inlet coolant flow is provided. This is aggravated, however, by the higher fuel bundle pressure drop associated with increased length and inlet flowrate. Further, stability at certain power rates requires rods be maintained short. If the boiling length is too long and the two-phase pressure drop too high, thermal-hydraulic, and thermal-hydraulic-nuclear instabilities arise. As a practical matter, the active fuel length is limited to about 12.5 feet (or 3.81 m using metric units). Once it is understood that both vessel diameter and fuel rod length are limited as a practical matter, it becomes clear that the total reactor volume available in any given reactor vessel approaches a limit. Therefore, the practical volume limit for a reactor is about 100,000 liters. When a reactor is built, many costs are fixed and constant regardless of the power output of the installed plant. If the installed plant can have a higher power density, these fixed and constant costs become substantially more efficient. Thus, there is a need for a new fuel design approach with potential to achieve higher power density to reduce the capital costs of nuclear reactors. This will enable any given reactor to have higher power output. The forced circulation boiling water reactor is one alternative reactor that is able to achieve the higher power density requirements. Simply stated, such reactors--by forcing the flow of coolant along internal paths--have the ability to concentrate more power in a given plant location. A new concept boiling water reactor which boils all of the entering coolant to steam and then superheats the steam is another reactor which can benefit from the use of this fuel design. See my copending patent application entitled "STEAM COOLED NUCLEAR REACTOR WITH BI-LEVEL CORE", Ser. No. 07/681,246, filed Apr. 4, 1991, which is incorporated herein by reference. CONVENTIONAL FUEL DESIGNS Conventional fuel designs for boiling water reactors include discrete fuel bundles having groups of vertically upstanding fuel rods supported on a lower tie plate and maintained vertical by an upper tie plate. A channel surrounds the vertically upstanding fuel rods between the tie plates and isolates the fluid flow between the tie plates from the rest of the reactor. Among other things, this arrangement allows predictability of fuel bundle performance down to the fuel bundle level. The chief concern with the design of modern fuel bundles has been nuclear efficiency improvement. Specifically, fuel bundles are designed to extract the maximum energy from the loaded nuclear fuel undergoing fission, typically by striving for uniform fuel rod power levels while minimizing the introduction of neutron absorbing materials in the core. For a number of practical reasons, however, modern fuel bundles utilized in boiling water reactors are not uniform and include heterogenous power outputs on the individual fuel rods within the fuel bundles. For example, the fuel bundle channels are surrounded on the outside by the so-called core bypass volume exterior of the fuel bundle, a volume which is filled with water during operation. For shutdown purposes, the water is displaced by the insertion of control rod blades. Furthermore, nuclear instruments which measure neutron and gamma flux in the core for the purpose of measuring local and global power levels are also located in the water filled bypass region. As a consequence, the fuel rods adjacent to the channel operate in a higher thermal neutron flux due to neutron moderation in the bypass water (which is greater than the moderation provided by the steam/water mixture interior to the bundle) and thus produce more power. To counter this, fuel enrichment is varied relative to these variant fast and slow neutron flux densities, and water rods replace select interior fuel rod locations for adding required fast neutron moderation with the end of maximum power extraction in mind. For at least these reasons, although the fuel bundles are isolated into discrete--and hence predictable increments--the discrete fuel rods within modern fuel bundles are not homogenous relative to one another in their power output. When the fuel rods within any given fuel bundle are not homogenous, this as a practical matters means that some portions of the fuel bundles reach their thermal limits before other portions of the fuel bundles. Those having skill in the art will understand that once a thermal limit is reached any where within a fuel bundle, the other portions of that same fuel bundle, and possibly other fuel bundles in the reactor core, are limited to that power output where the local thermal limit will not be exceeded. STATEMENT OF THE PROBLEM TO BE SOLVED Although modern fuel design has been concerned with nuclear efficiency, when contemplating the appropriate power density for a new nuclear power plant design, there is a tradeoff between nuclear efficiency as it may impact energy utilization and fuel cycle costs--which generally favors low power density--and the fixed plant capital costs incurred at the time of plant construction--which favor high power density to gain improvement in economy of scale. For a high power density plant, certain conventional design constraints in establishing fuel bundle design will be ignored. Since this is the case, the reader will understand that the invention is claimed insofar as departure from these conventional design constraints are concerned. Thus the realization that fuel cycle costs are secondary to plant capital outlay as a practical matter and the concession of nuclear efficiency as a traditional constraint are part of the invention set forth in the following specification. SUMMARY OF THE INVENTION This invention approaches the problem of achieving higher power density by proposing a fuel design which does not necessarily emphasize nuclear efficiency, although some design elements are not inconsistent with this conventional goal either. Instead the design emphasis is on uniformity of fuel rod power output throughout the core. There results a reactor core with discrete fuel bundle units where all rods many uniformly approach their respective thermal limits. With all rods approaching their respective thermal limits with uniformity, it is possible to impart a high power density to the reactor. In the new design, the traditional BWR fuel channel surrounding a group of fuel rods is eliminated. In place of the traditional channel surrounding a group of fuel rods, each fuel rod is surrounded by its own individual cylindrical channel. This individual cylindrical channel on each fuel rod provides thermal hydraulic and heat transfer advantages to enable all fuel rods within the fuel bundle to uniformly approach their own thermal limits. At the same time, the individual fuel rod channels retain the concept of predictably segregating the fuel core into discrete fuel rod units to assure acceptable flow distributions without the need for complex 3-D analyses and multi-assembly thermal hydraulic confirmatory tests. The preferred fuel rod pitch is a triangular pitch between the individual fuel rods as they are discretely surrounded by their own channel. The new triangular geometry provides for more uniform (flat) power distributions within all fuel rods--and hence all groups of fuel rods. Bypass flow is introduced uniformly between the fuel rod channels, rather than heterogeneously in the channel gap and water rods as in present BWR fuel designs. Individual fuel rod channels can be orificed differently, as required, to match inlet flow to fuel rod power output to maintain uniformity between all fuel rods as they approach their respective thermal limits. Gaps between bundles can be eliminated, or at least minimized, yielding even higher power density. Furthermore, for regions of the cores where steam cooling is significant, radiant transfer of heat between the outer surface of the fuel rod and the inner surface of the channel appreciably improves overall heat transfer to the steam coolant (on the order of 5 to 104 of the total heat transferred). Spacers are judiciously applied within the fuel rod channel to limit relative displacement between the channel wall and fuel rod cladding and to serve as turbulent flow promoters.
	description	A computer readable text file, entitled “045636-5285_SequenceListing.txt,” created on or about Jan. 19, 2016 with a file size of about 97 KB contains the sequence listing for this application and is hereby incorporated by reference in its entirety. The present relates to new uranium-chelating peptides derived from EF-hand calcium-binding motif, useful for uranium biodetection and biodecontamination. Uranium is a radioactive heavy metal, which is naturally present in varying concentrations in the environment. However, the wide use of uranium for industrial and military applications increases the risk of its distribution in the environment, which is aggravated by such factors as mining activities, uranium processing, or leaching of radioactive wastes. Uranium presents radiological and chemical toxicity to living organisms. The linear dioxo uranyl form (UO22+) which corresponds to uranium in its hexavalent oxidation state U(VI) is the prevalent form of uranium in the presence of oxygen and the most stable chemical form of uranium in water. It is soluble, bioavailable, and thus potentially toxic. Therefore, it is of high interest to develop systems allowing uranyl detection in the environment as well as molecules allowing its complexation in various environments with high affinity and selectivity. In particular, sensitive and easy to use systems allowing the detection of uranyl content in waters at the concentration levels defined by World Health Organization (WHO)(inferior to 0.03 mg/L, i.e. 126 nM; Guidelines for drinking-water quality, Fourth Edition, 2011, World Health Organization, WHO Press, Geneva) would be of great help for the water level monitoring. Among these systems, molecules derived from peptides are advantageous in that they are non toxic, and can be easily produced either synthetically or using recombinant techniques. Similarly, the development of organisms bearing uranyl biosensors, capable of detecting the uranyl fraction that is bioavailable and thus potentially toxic, is needed to assess water quality on a long term basis. Finally, bioremediation is an emerging technique that would allow the decontamination of large areas of contaminated water and/or soils. The helix-loop-helix calcium-binding motif (EF-hand motif) is the most prevalent Ca2+-binding site in proteins. The canonical EF-hand motif of about 30 amino acids in length is structured by two alpha-helices bridged by a flexible metal-binding loop (also referred to as calcium-binding loop, calcium-binding site, loop or site) composed of 12 highly conserved residues, with calcium coordinating positions at 1 (+X), 3 (+Y), 5 (+Z), 7 (−Y), 9 (−X) and 12 (−Z). The residues at the ligand positions 1, 3, 5 and 12 and also at the non-ligand positions 6 and 8 are highly conserved. The calcium ion is coordinated in a pentagonal bipyramidal configuration with a coordination number of 7 to side-chain oxygen bearing groups at positions 1, 3, and 5, a water molecule hydrogen bonded to residue at position 9, and the main chain carbonyl group of residue 7. The pentagonal bipyramidal configuration arises from two additional ligands provided by a bidendate glutamic or a monodentate aspartic acid which stabilizes a water ligand, in position 12. The residue at position 1 of the loop is most frequently occupied by an aspartate (D); two residues are found at position 3: aspartic acid (D) or asparagine (N), but most frequently D; position 5 is most often occupied by aspartic acid (D), serine (S) or asparagine (N); the residue at position 7 is variable; position 9 shows a preference for residues with a side-chain oxygen (D, N, E, S, T), and the residues more frequently found at position 12 are glutamate (E) and aspartate (D), most frequently E. The highly conserved residues at the non ligand positions 6 and 8 are Gly (G) and Ile (I), respectively. The majority of the known EF-hand Calcium-Binding proteins (CaBPs) contain paired EF-hand motifs. Functionally, the EF-hand proteins can be divided into two classes: 1) signaling proteins and 2) buffering/transport proteins. The first group is the largest and includes the most well-known members of the family such as calmodulin, troponin C and S100B. These proteins typically undergo a calcium-dependent conformational change which opens a target-binding site. The latter group is represented by calbindin D9k which remains in a closed conformation upon calcium binding. Calmodulin (CaM) is the most studied representative of the ubiquitous EF-hand protein family and a calcium-binding protein involved in the regulation of a wide range of target enzymes. The calmodulin structure (PDB code 1EXR) includes two pairs of EF-hand motifs (EF-hands 1 and 2; EF-hands 3 and 4) in two domains (domain 1 and 2) separated by a flexible α-helix (FIG. 1A). In EF-hand1, calcium ligands are provided by three monodentate aspartate (D) at positions 1, 3, 5 of the metal-binding loop (D1, D3, D5), a bidentate glutamate at position 12 (E12), a main chain carbonyl at position 7 and a water molecule stabilized by threonine 9 (T9) side chain, as schematized in FIG. 1B. Fluorescent sensors for calcium, called cameleons, have been constructed based on green fluorescent proteins and calmodulin (Miyawaki et al., Nature, 1997, 388, 882-887; Nagai et al., PNAS, 2004, 101, 10554-10559). They are chimeric proteins composed of a short-wavelength variant of GFP, CaM, a glycylglycine linker, the CaM-binding peptide of myosin light-chain kinase (M13), and a long-wavelength variant of GFP. Ca2+ binding to CaM initiates an intramolecular interaction between CaM and M13, which changes the chimeric protein from an extended to a more compact conformation, thereby increasing the efficiency of Fluorescence Resonance Energy Transfer (FRET) from the shorter to the longer-wavelength variant of GFP. Yellow cameleons (YCs) have cyan and yellow fluorescent proteins (CFP and GFP) as the FRET donor and acceptor, respectively. Synthetic cyclic-peptide variants of calmodulin site 1 (CaM-Mc peptides), consisting of a 33 amino acid sequence in which one, two or three of the aspartic acid residues in positions 1, 3 and 5 of the calcium-binding loop (D1, D3, D5) are substituted with neutral amino acids (T, N or S) and a tyrosine residue is introduced in position 7 of the loop to monitor metal binding using tyrosine fluorescence, bind uranyl with an apparent dissociation constant in the micromolar range (Kd of 9.8 to 54.10−6 M) while they don't bind calcium (WO 2005/012336). However, uranyl biosensors with detection limits in the nanomolar range or below are required to detect uranium content in waters at the maximum concentration levels defined by WHO. A recombinant phosphorylated variant of calmodulin domain 1, CaM1P, in which the threonine at position 9 of the EF-hand1 loop is phosphorylated, was shown to bind uranyl with a dissociation constant in the subnanomolar range, at pH 7 (Kd of 3.10−10 M; Pardoux et al., 2012 PLoS ONE, 2012, 7, e41922). CaM1P is derived from CaM1 which consists of a 77 amino acids sequence, in which: (i) the T9TKE12 sequence of EF-hand1 loop is substituted by the CK2 recognition sequence TAAE to allow phosphorylation of the threonine 9, in vitro, using recombinant catalytic subunit of protein kinase CK2, (ii) a tyrosine residue is introduced in position 7 of the EF-hand 1 loop so that uranyl and calcium-binding affinities could be determined by following tyrosine fluorescence emission at 302 nm, and (iii) the metal-binding ability of site 2 is impaired by substituting the two aspartate residues in positions 1 and 3 of the loop with alanine residues. Phosphorylation of the threonine at position 9 of the metal-binding loop increased uranyl-binding affinity by a factor of 5 at pH 6, while increasing the pH to 7 led to a further enhancement in uranyl affinity by a factor of 15.6. Analysis of the infrared modes of the phosphoryl group indicated that this group was deprotonated at pH 7 and directly involved in uranyl coordination. However, CaM1P affinity for calcium (˜20.10−6 M) is similar to that of CaM domain 1 so that its selectivity for uranyl over calcium is low (4.103 at pH 6 and 6.104 at pH 7). In addition CaM1P cannot be expressed in a recombinant cell, microorganism or plant, which is then used for the in situ biodetection or bioremediation of uranyl because the phosphorylation of the Threonine 9 is performed in vitro. In this context, new sensitive and specific metal biosensors and/or chelators would be useful for the development of cost-effective uranium biodetection and bioremediation strategies. The inventors have determined a structural model of the complex formed by the phosphorylated CaM1 peptide (CaM1P) with uranyl using a molecular dynamics approach. This structural model suggested that at least two residues of the calcium-binding loop are not necessary to bind uranyl in the complex: at least one of the calcium-ligating residues (aspartate at position 3 or D3) and its directly adjacent residue (Lysine at position 2 or K2; FIG. 2A). This result encouraged the inventors to produce a variant CaMΔ by the deletion of these two residues of the loop (K2 and D3) formerly to analyse the resulting properties of the phosphorylated peptide CaMΔ-P (FIGS. 1C and 2B). They also analyzed, the non phosphorylated peptide CaMΔ(FIG. 2D), which showed a very high affinity for uranyl, and a low affinity for calcium, as demonstrated in the examples of the present application (FIGS. 3 and 4). The rationale of this high affinity for uranyl on one hand and for high specificity for uranyl as compared to calcium on the other hand resides in that less ligands are necessary to complete the coordination sphere of uranyl (i.e. 5 to 6 ligands disposed in the equatorial plane) than to coordinate calcium (7 to 8 ligands, 7 ligands in site 1 of calmodulin) and in that the binding loop containing 12 residues in site 1 is too large to accommodate uranyl, i.e. to optimally dispose the uranyl ligands in an equatorial plane around the uranyl UO2 axis. These latter findings were obtained from the molecular dynamics simulations on phosphorylated CaM1P peptide (FIG. 2A) but they were also observed on the non-phosphorylated peptide CaM1 (FIG. 2C). In particular, according to the structural model of the CaM1-U complex, Asp at position 1 of the loop is not a uranyl ligand and it is situated below the uranyl equatorial plane (FIG. 2C). In addition, the loop arrangement in the model structure of the CaM1-U complex is not ideal as compared to the structural model of CaMΔ(FIG. 2D), in that the distance is too long between the Asp ligand and the Glu ligand, and the structure involves a carbonyl ligand (the carbonyl group of Tyr7) that is considered as a weaker ligand as compared to the side chain of aspartate. Therefore, the present invention concerns the optimisation of uranyl binding sites in EF-hand motifs by decreasing the size of the binding loop by two amino acids, and by suppressing at least one calcium ligand, to obtain affine and specific uranyl binding sites. As shown in the examples by the comparison of uranyl binding affinities of CaMΔ and CaMΔ3 (where only the aspartate at position 3 was deleted), two deletions are necessary to increase uranyl affinity. For the EF-hand1 of calmodulin, as demonstrated in the examples, deletion of the amino acids at positions 1 and 2 or 2 and 3 is highly efficient to increase uranyl affinity and specificity. More generally for other EF-hand motifs, the position of the deletions may depend on the sequence of these motifs. This is illustrated for site 2 by showing different possibilities to increase uranyl affinity and specificity, obtained using structure prediction by molecular dynamics simulations (FIG. 10). One aspect of the present invention relates to a polypeptide comprising at least one helix-loop-helix calcium-binding (EF-hand) motif, which comprises a deletion of at least two amino acid residues in the 12-amino-acid calcium-binding loop sequence, and wherein said polypeptide binds uranyl. The polypeptide of the invention which is an isolated recombinant or synthetic polypeptide, has a signicantly higher binding affinity for uranyl and a significantly lower binding affinity for calcium than the corresponding peptide without said deletion. In the present application, “significant” means that the binding affinity is different with P<0.01. Binding affinity for metals can be measured by any standard technique which is known by those skilled in the art such as those described in the examples of the present application. Preferably, the polypeptide of the invention has a binding affinity for uranyl which is increased by a factor of at least 2, more preferably at least 5, 10, 30, 100 or more and a binding affinity for calcium which is decreased by a factor of at least 2, more preferably at least 5, 10, 30, 100, 300 or more, compared to the corresponding peptide without the deletion in the calcium-binding loop. Preferably, the polypeptide of the invention has a selectivity for uranyl over calcium which is of at least 103, more preferably at least 104, 105, 106, 107 or more. For example, the CaMΔ peptide of the example has a binding affinity for uranyl which is increased by a factor of at least 100 and a binding affinity for calcium which is decreased by a factor of at least 500 compared to the corresponding peptide CaM1 which does not have the deletion in the calcium-binding loop. Therefore the selectivity of CaMΔ for uranyl over calcium is of the order of 107 whereas that of CaM1 is only of the order of 103. The polypeptide of the invention and its derivatives like the cameleon-based biosensors, have the following advantages: they have a high binding affinity for uranyl combined with a low binding affinity for calcium, which means that they are highly sensitive and selective for uranyl. Therefore, they can detect low uranium concentration in complex media containing divalent cations like Ca2+ (for example, biological media, calcium-rich water). Uranyl detection in a sample to analyze can be performed in vitro using the isolated polypeptide or cameleon-based biosensor, as well as in situ in recombinant cells (whole-cell biosensors) or non-human transgenic organisms expressing the cameleon protein derived from the polypeptide of the invention. Their affinity and selectivity for uranium are higher than those of all calmodulin-derived uranium biosensors. the cameleon biosensors derived from the polypeptide of the invention can also be used as imaging biosensors to visualize uranyl in situ in recombinant cells or non-human transgenic organisms expressing the cameleon protein derived from the polypeptide of the invention, the recombinant cells and non-human transgenic organisms expressing the polypeptide or its derivatives can be used for the biodecontamination and the bioremediation of uranium contamination in an environment, as well as for the production of large quantities of the polypeptide of the invention and its derivatives (cameleon-based biosensors). as recombinant proteins, their production and use are easy, fast not-toxic, and cost-effective, and they are designed for in vitro and in vivo uses. In the following description, the standard one letter amino acid code is used. The expression “EF-hand motif” refers to the canonical EF-hand calcium-binding motif as described just before. In one embodiment, the deletion includes at least one calcium-ligating residue (residue in position 1, 3, 5, 7, 9, 12 of the calcium-binding loop sequence). Preferably, the deletion includes at least one of the calcium-ligating residues in positions 1, 3, and/or 5 of the calcium-binding loop sequence, more preferably in positions 1 and/or 3. Even more preferably, the deletion includes at least the calcium-ligating residue in position 1 or 3 of the calcium-binding loop. In an advantageous arrangement of said embodiment, the polypeptide comprises a deletion of at least one calcium-ligating residue and its directly adjacent residue (i.e., residue in position +1 or −1 relative to the calcium-ligating residue). Preferably, the polypeptide comprises a deletion of at least one of the following pairs of residues: positions 1 and 2, 2 and 3, 3 and 4, 4 and 5, 5 and 6 of the calcium-binding loop. More preferably, the polypeptide comprises a deletion of at least the pair of residues in positions 1 and 2 or 2 and 3 of the calcium-binding loop. In another advantageous arrangement of said embodiment, the polypeptide comprises a deletion of at least one calcium-ligating residue and at least one of the residues in positions 10 and/or 11 of the calcium-binding loop. Preferably, the polypeptide comprises a deletion of at least one calcium-ligating residue in position 1 or 3 and at least one of the residues in positions 10 and/or 11 of the calcium-binding loop. More preferably, the polypeptide comprises a deletion of at least the residues chosen from positions 3 and 10 and positions 3, 10 and 11. In another preferred embodiment, the polypeptide comprises at least two EF-hand motifs, wherein at least one EF-hand motif comprises said deletion in the loop sequence and the other EF-hand motif(s) comprise(s) said deletion in the loop sequence or not. Preferably, the polypeptide comprises two to four EF-hand motifs. More preferably, the polypeptide comprises two or four EF-hand motifs. In another preferred embodiment, the polypeptide comprises further alterations in said EF-hand motif(s) which comprise said deletion or not, such as for example the substitution and/or the modification of one or more amino acid residues. Said alterations are introduced when the amino acid residues of interest are not naturally present at the appropriate positions in said EF-hand motif(s). Preferably, said further alterations are in the loop sequence. In a first advantageous arrangement of said embodiment, the polypeptide comprises a fluorescent residue, preferably a tyrosine or tryptophan residue. The fluorescent residue is advantageously in the loop from said at least one EF-hand motif which comprises said deletion or not, or in close proximity to said loop. It is preferably in position 7 of said loop, by reference to the numbering of the 12-amino-acid loop sequence. Preferably, the fluorescence residue is in the loop from said at least one EF-hand motif which comprises said deletion. More preferably, the polypeptide comprises a tyrosine residue in position 7 of the loop from said at least one EF-hand motif which comprises said deletion. The fluorescent residue allows the monitoring of uranyl and/or calcium binding and the determination of their binding affinities, by following tyrosine fluorescence emission at 302 nm. The fluorescent residue is an amino acid residue naturally present in the EF-hand motif(s) or substituted. In a second advantageous arrangement of said embodiment, the polypeptide comprises at least two aspartic acid residues in positions 1, 3 and/or 5 of the loop from said at least one EF-hand motif which comprises said deletion, by reference to the numbering of the 12-amino-acid loop sequence. The aspartic acid residues are amino acid residues naturally present in the EF-hand motif(s) or substituted. In a third advantageous arrangement of said embodiment, the polypeptide comprises a glycine residue in position 4 of the loop from said at least one EF-hand motif which comprises said deletion or not, by reference to the numbering of the 12-amino-acid loop sequence. Preferably, the glycine residue is in the loop from said at least one EF-hand motif which comprises said deletion. The glycine residue is an amino acid residue naturally present in the EF-hand motif(s) or substituted. In another advantageous arrangement of said embodiment, the polypeptide comprises at least one phosphorylated serine or threonine residue. The phosphorylated serine or threonine residues are advantageously in the loop from said EF-hand motif(s) which comprise said deletion or not, preferably in position 9 and/or 12 of the loop from said EF-hand motif(s), by reference to the numbering of the 12-amino-acid loop sequence. The phosphorylation of said residue(s) increases the uranyl binding affinity of the polypeptide. The residues in positions+1 to +3 relative to the phosphorylated threonine are advantageously modified to provide a CK2 recognition sequence TXXE, in which X is a neutral or acidic amino acid different from T, for example XX is AA or AE. Phosphorylation of the threonine may be performed in vitro, using recombinant catalytic subunit of protein kinase CK2. Preferably, the polypeptide comprises a phosphorylated threonine residue in position 9 of the loop from said EF-hand motif(s) which comprise(s) said deletion or not and further comprises alanine residues in positions 10 and 11 of said loop, by reference to the numbering of the 12-amino-acid loop sequence. These alanine residues provide a CK2 recognition sequence TAAE to allow phosphorylation of the Threonine 9. The phosphorylated serine or threonine residues are advantageously in the loop from said at least one EF-hand motif which comprises said deletion. The serine and threonine residues of the EF-hand motif(s) which are modified by phosphorylation and the adjacent residues which are substituted to provide a CK2 recognition site are naturally present in the EF-hand motif(s) or substituted. In another advantageous arrangement of said embodiment, the polypeptide comprises at least two EF-hand motifs, at least one comprising said deletion in the loop sequence and at least another one not comprising said deletion, wherein at least one of said EF-hand motif(s) not comprising the deletion comprises at least one mutation in the loop sequence which impairs calcium binding. Preferably, said mutation is the substitution with alanine residues of the residues in positions 1 and 3 of the loop by reference to the numbering of the 12-amino-acid loop sequence. The EF-hand motif sequence is modified by standard mutagenesis technique on the polypeptide coding sequence. The phosphorylation of the serine and/or threonine residues is performed using standard methods which are known from those skilled in the art. The amino acid-sequence of the EF-hand motif(s) of the polypeptide of the invention is that of the corresponding wild-type EF-hand protein(s) except at said amino acid position(s) which are altered in the present invention. The polypeptide of the invention may be derived from EF-hand motif(s) of any proteins of the EF-hand family (EF-hand protein) having a canonical EF-hand motif as above described. Preferably, the polypeptide of the invention is derived from EF-hand protein(s) from the class of EF-hand signaling proteins, i.e., the EF-hand proteins which undergo a calcium-dependent conformational change. More preferably, it is derived from EF-hand signaling protein(s) of the calmodulin superfamily. Even more preferably, from EF-hand signaling protein(s) of the calmodulin superfamily selected from the group consisting of calmodulin and troponin C. It is advantageously derived from EF-hand1, 2, 3 and/or 4 of calmodulin protein(s). In an advantageous arrangement of said embodiment, the polypeptide is derived from Arabidopsis thaliana calmodulin 3 (amino acid sequence SEQ ID NO: 2 encoded by the cDNA of SEQ ID NO: 1). The calmodulin EF-hand1, 2, 3 and 4 correspond respectively to positions 12 to 41, 48 to 76, 85 to 114, and 121 to 149, by reference to the amino acid numbering of Arabidopsis thaliana calmodulin 3 (SEQ ID NO: 2). The calcium-binding loop of EF-hand1, 2, 3 and 4 correspond respectively to positions 21 to 32, 57 to 68, 94 to 105, and 130 to 141, by reference to the amino acid numbering of SEQ ID NO: 2. The calmodulin domain 1 and 2 correspond respectively to positions 1 to 76 and 77 to 149, by reference to the amino acid numbering of SEQ ID NO: 2. In another advantageous arrangement of said embodiment, the polypeptide comprises a EF-hand motif derived from a calmodulin EF-hand1 having a 12 amino-acid loop of sequence (I): X1-X2-X3-X4-X5-X6-X7-X8-X9-X1-X11-X12, in which: X1 is D; X2 is K or R, preferably K; X3 is D; X4 is G, N, Q, preferably G; X5 is D or N, preferably D; X6 is G; X7 is T, C, S or N, preferably, T; X8 is I; X9 is T or S, preferably T; X10 is T or S, preferably T; X11 is K, S, M or N, preferably K, and X12 is E. More preferably, said EF-hand1 has a 12 amino-acid loop of sequence DKDGDGCITTKE (SEQ ID NO: 3). In another advantageous arrangement of said embodiment, the polypeptide comprises a EF-hand motif derived from a calmodulin EF-hand2 having a 12 amino-acid loop of sequence (II): X1-X2-X3-X4-X5-X6-X7-X8-X9-X10-X11-X12, in which: X1 is D; X2 is A, V or Q, preferably A; X3 is D; X4 is G, N; X5 is N, D or S, preferably N; X6 is G or H, preferably, G; X7 is T, N or Q, preferably, T; X8 is I; X9 is D or E, preferably D; X10 is F; X11 is P, T or S, preferably P, and X12 is E. More preferably, said EF-hand2 has a 12 amino-acid loop of sequence DADGNGTIDFPE (SEQ ID NO: 4). In another advantageous arrangement of said embodiment, the polypeptide comprises a EF-hand motif derived from a calmodulin EF-hand3 having a 12 amino-acid loop of sequence DKDQNGFISAAE (SEQ ID NO: 5) In another advantageous arrangement of said embodiment, the polypeptide comprises a EF-hand motif derived from a calmodulin EF-hand4 having a 12 amino-acid loop of sequence DVDGDGQINYEE (SEQ ID NO: 6). A more preferred polypeptide of the invention is derived from calmodulin EF-hand1, EF-hand2, EF-hand3 and/or EF-hand 4 and comprises a calcium-binding loop sequence having a deletion of at least two amino acids, which is selected from the group consisting of the sequences: DGDGCITTKE (SEQ ID NO: 7), DGDGYITTKE (SEQ ID NO: 8), DGDGYITAAE (SEQ ID NO: 9), DGNGTIDFPE (SEQ ID NO: 10), DGNGYIDFPE (SEQ ID NO: 11), DGDGTIDFPE (SEQ ID NO: 12) DGDGYIDFPE (SEQ ID NO: 13), DQNGFISAAE (SEQ ID NO: 14) and DGDGQINYEE (SEQ ID NO: 15), KDGDGCITKE (SEQ ID NO: 70), KDGDGCITTE (SEQ ID NO: 71), DKGDGCITKE (SEQ ID NO: 72), DKGDGCITTE (SEQ ID NO: 73), KDGDGCITE (SEQ ID NO: 74), DKGDGCITE (SEQ ID NO: 75), ADGNGTIDPE (SEQ ID NO: 76), ADGNGTIDFE (SEQ ID NO: 77), DAGNGTIDPE (SEQ ID NO: 78), DAGNGTIDFE (SEQ ID NO: 79), ADGNGTIDE (SEQ ID NO: 80), DAGNGTIDE (SEQ ID NO: 81), KDQNGFISAE (SEQ ID NO: 82), KDQNGFISAE (SEQ ID NO: 83), DKQNGFISAE (SEQ ID NO: 84), DKQNGFISAE (SEQ ID NO: 85), KDQNGFISE (SEQ ID NO: 86), DKQNGFISE (SEQ ID NO: 87), VDGDGQINEE (SEQ ID NO: 88), VDGDGQINYE (SEQ ID NO: 89), DVGDGQINEE (SEQ ID NO: 90), DVGDGQINYE (SEQ ID NO: 91), VDGDGQINE (SEQ ID NO: 92), DVGDGQINE (SEQ ID NO: 93). Preferably from the group consisting of the sequences SEQ ID NO: 7 to 15, 72, 75, 78, 81, 84, 87, 90 and 93. In another advantageous arrangement of said embodiment, the polypeptide of the invention is a calmodulin domain 1 variant comprising two EF-hand motifs, respectively from EF-hand1 and EF-hand2 of calmodulin protein(s). A preferred calmodulin domain 1 variant polypeptide comprises a EF-hand1 comprising the deletion of the amino acid residues in positions 1 and 2 or 2 and 3 and a EF-hand2 comprising the substitution of the residues in positions 1 and 3 of the loop with alanine residues, which impairs metal binding in site 2. Advantageously, the EF-hand1 further comprises a tyrosine residue in position 7 and/or neutral or acidic residues different from T in positions 10 and 11 of the loop, for example AA or AE. More preferably, said calmodulin domain 1 variant polypeptide comprises or consists of the sequence SEQ ID NO: 17 or 60, which correspond to the peptides referred to as CaMΔ and CaMΔ-WT in the examples of the present application. CaMΔ and CaMΔ-WT are variants of the domain 1 from Arabidopsis thaliana calmodulin 3. Another preferred calmodulin domain 1 variant polypeptide comprises a EF-hand1 comprising the deletion of the amino acid residues in positions 1 and 2 or 2 and 3 and a EF-hand2 comprising the deletion of at least one calcium-ligating residue in position 1 or 3 and at least one of the residues in positions 10 and/or 11 of the calcium-binding loop, preferably the residues in positions 3 and 10 or 3, 10 and 11. Another preferred calmodulin domain 1 variant polypeptide comprises a EF-hand1 and EF-hand2, each comprising the deletion of the amino acid residues in positions 1 and 2 or 2 and 3 of the calcium-binding loop. In another advantageous arrangement of said embodiment, the polypeptide of the invention is a calmodulin variant comprising four EF-hand motifs, respectively from EF-hand1, 2, 3 and 4 of calmodulin protein(s). In a preferred calmodulin variant polypeptide, the EF-hand1 comprises the deletion of the amino acid residues in positions 1 and 2 or 2 and 3 and the EF-hand2, EF-hand3 and EF-hand4 comprise no deletion. More preferably, said polypeptide comprises or consists of the sequence SEQ ID NO: 18 derived from Arabidopsis thaliana calmodulin 3. In another preferred calmodulin variant polypeptide, the EF-hand1 comprises the deletion of the amino acid residues in positions 1 and 2 or 2 and 3, the EF-hand2 comprises the deletion of at least one calcium-ligating residue in position 1 or 3 and at least one of the residues in positions 10 and/or 11 of the calcium-binding loop, preferably the residues in positions 3 and 10 or 3, 10 and 11, and the EF-hand3 and EF-hand4 comprise no deletion. In another preferred calmodulin variant polypeptide, each of the EF-hand1 and EF-hand2 comprise the deletion of the amino acid residues in positions 1 and 2 or 2 and 3 and the EF-hand3 and EF-hand4 comprise no deletion. In another preferred calmodulin variant polypeptide, each of the EF-hand1, 2 and 3 comprise the deletion of the amino acid residues in positions 1 and 2 or 2 and 3 and the EF-hand4 comprises no deletion. In another preferred calmodulin variant polypeptide, each of the EF-hand1, 2, 3 and 4 comprise the deletion of the amino acid residues in positions 1 and 2 or 2 and 3. Even more preferably, said polypeptide comprises or consists of the sequence SEQ ID NO: 20 which is derived from Arabidopsis thaliana calmodulin 3. In another preferred calmodulin variant polypeptide, each of the EF-hand1 and EF-hand3 comprise the deletion of the amino acid residues in positions 1 and 2 or 2 and 3 and the EF-hand2 and EF-hand4 comprise no deletion. In another preferred embodiment, the polypeptide is coupled to a labeling agent which produces a detectable and/or quantifiable signal, in particular a radioactive, magnetic or luminescent (radioluminescent, chemiluminescent, bioluminescent, fluorescent or phosphorescent) agent. The labeled polypeptide may be labeled directly or indirectly, via covalent or non-covalent bonds, using standard conjugation techniques that are well-known to those skilled in the art. Another aspect of the present invention relates to a fusion or chimeric protein comprising the polypeptide fused to another protein moiety, directly or through a peptide spacer. The protein/peptide moieties include those which allow the purification, detection, immobilization, and/or cellular targeting of the polypeptide of the invention, and/or which increase the affinity for uranyl, the bioavailability, and/or the production in expression systems of said polypeptide. These moieties may be selected from: (i) a labeling moiety such as a fluorescent protein (GFP and its derivatives, BlueFP, CyanFP, YellowFP, GreenFP and red-shifted GFP), (ii) a reporter moiety such as an enzyme tag (luciferase, alkaline phosphatase, glutathione-S-transferase (GST), β-galactosidase), (iii) a binding moiety such as an epitope tag (polyHis6, FLAG, HA, myc.), a DNA-binding domain, a hormone-binding domain, a poly-lysine tag for immobilization onto a support, and (iv) a targeting moiety for addressing the chimeric protein to a specific cell type or cell compartment. In addition, the sequence(s) advantageously comprise a linker which is long enough to avoid inhibiting interactions between said sequence(s) and the polypeptide sequence. The linker may also comprise a recognition site for a protease, for example, for removing affinity tags from the purified chimeric protein according to the present invention. In a preferred embodiment the chimeric protein is a cameleon protein comprising tandem fusions of (1) the polypeptide of the invention, (2) a EF-hand protein-binding peptide that binds a complex between the polypeptide in (1) and calcium and/or uranyl, (3) a fluorescence-donor protein, and (4) a fluorescence-acceptor protein, wherein the fluorescence donor and acceptor proteins are at each end of the cameleon protein. In some arrangements of said embodiment, the EF-hand protein-binding peptide is absent; in these arrangements, the polypeptide of the invention usually comprises two EF-hand motifs. Cameleon proteins without EF-hand protein-binding peptide may be derived from the sequence SEQ ID NO: 65. In other arrangements of said embodiment, the cameleon protein further comprises a linker between the fluorescence donor and/or acceptor and the polypeptide of the invention, between the polypeptide of the invention and the EF-hand protein-binding peptide, and/or between the EF-hand protein-binding peptide and the fluorescence acceptor. The fluorescence donor and acceptor proteins which are advantageously at each end of the cameleon protein are chosen from any protein capable of producing FRET such as with no limitation: Alexa proteins and GFP variants such as those disclosed for example in Shaner et al., Nature Methods, 2005, 12, 905-909; Erard et al., Molecular Biosystems, 2013, 9, 258-267; Fredj et al., PLOS ONE, 2012, 7, e49149 and PCT Application WO/2012/172095. The fluorescence donor and acceptor proteins are advantageously chosen from a short-wavelength variant of GFP such as CyanFP or BlueFP, Turquoise, Turquoise 2, Aquamarine, Cerulean, Cerulean3, TFP1 and a long wave-length variant of GFP such as YellowFP, GreenFP and red-shifted GFP, Citrine, Venus and circularly permuted fluorescent proteins. The polypeptide of the invention comprises advantageously four EF-hand motifs from EF-hand signaling protein(s) as defined above. Preferably said EF-hand motifs are from EF-hand signaling protein(s) of the calmodulin superfamily selected from the group consisting of calmodulin and troponin C. In an advantageous arrangement of said embodiment, the cameleon protein is derived from calmodulin. Many peptides which bind calmodulin in complex with calcium are known in the art (see for example Carafoli et al., Proc. Natl. Acad. Sci. USA., 2002, 99:1115-1122). Any of these peptides can be used in the cameleon protein of the invention, including with no limitations: the peptides M13 (amino acid sequence SEQ ID NO: 22 encoded by the nucleotide sequence SEQ ID NO: 21) and skMLCK (SEQ ID NO: 23) from skeletal myosin light chain kinase; the peptides MLCKp (SEQ ID NO: 24) and smMLCK (SEQ ID NO: 25) from myosin light chain kinase; the peptide named wasp venom or polistes mastoparan (SEQ ID NO: 26); the peptide p21 (SEQ ID NO: 27); the peptides disclosed in Shifman J. M. and Mayo, L., PNAS, 2003, 100, 13274-such as melittin (SEQ ID NO: 28), spectrin (SEQ ID NO: 29), CaMKI (SEQ ID NO: 30), CaMKII (SEQ ID NO: 31), CaMKK (SEQ ID NO: 32) and peptide1 (SEQ ID NO: 33); the peptides from cyclic nucleotide phosphodiesterase (Olwin & Storm, 1985); the peptides from caldesmon (Yazawa et al., 1987) and the synthetic peptide derived from the plasma membrane Ca2+ pump (Yazawa et al., 1992). Preferably, the cameleon protein comprises a short-wave-length variant of GFP such as CyanFP or BlueFP, a polypeptide of the invention derived from calmodulin, a linker, the calmodulin-binding peptide of myosin light chain kinase (peptide M13), and a long wave-length variant of GFP such as YellowFP, GreenFP and red-shifted GFP. Preferred cameleon proteins are derived from the calmodulin variant polypeptides as defined above. Examples of preferred calmodulin-derived cameleon proteins of the invention comprise or consist of an amino acid sequence selected from the group consisting of the sequences SEQ ID NO: 35, 38, 61, 63 and 67. Alternatively, the four elements of the cameleon protein as described above can be divided in two separate fusion proteins, which are then combined together to obtain a functional biosensor capable of detecting uranium: a first fusion protein with the fluorescence donor fused to one of the polypeptide or the polypeptide-binding peptide, and a second fusion protein with the fluorescence acceptor fused to the polypeptide or polypeptide-binding peptide which is not fused to the fluorescence donor. These types of cameleon proteins are described for example in Miyawaki et al., Proc. Natl. Acad. Sci. USA., 1999, 96, 2135-40. The cameleon protein is a uranyl biosensor that can be used in vitro as uranyl analysis reagent for the detection of uranyl in an environment (water, soil, effluents) or in biological samples from individuals (biological fluids). It is also used as cell imaging reagent or diagnostic reagent for the detection of uranyl in situ in recombinant cells (whole-cell biosensor) or non-human transgenic organisms expressing the cameleon protein. The invention encompasses polypeptides and derived fusion proteins comprising or consisting of natural amino acids (20 gene-encoded amino acids in a L- and/or D-configuration) linked via a peptide bond as well as peptidomimetics of such protein where the amino acid(s) and/or peptide bond(s) have been replaced by functional analogues. Such functional analogues include all known amino acids other than said 20 gene-encoded amino acids. A non-limitative list of non-coded amino acids is provided in Table 1A of US 2008/0234183 which is incorporated herein by reference. The invention also encompasses modified polypeptides/fusion proteins derived from the above polypeptides/fusion proteins by introduction of any modification into one or more amino acid residues, peptide bonds, N- and/or C-terminal ends of the protein, as long as the uranyl-binding activity is maintained in the modified polypeptide/protein. These modifications which are introduced into the polypeptide/protein by the conventional methods known to those skilled in the art, include, in a non-limiting manner: the substitution of a natural amino acid with a non-proteinogenic amino acid (D amino acid or amino acid analog); the modification of the peptide bond, in particular with a bond of the retro or retro-inverso type or a bond different from the peptide bond; the cyclization, and the addition of a chemical group to the side chain or the end(s) of the protein, in particular for coupling an agent of interest to the polypeptide/fusion protein of the invention. In another preferred embodiment, the polypeptide or fusion protein is immobilized on the surface of a solid support, such as with no limitation, a plate, a slide, a strip, a fiber, a gel, a felt support, wells, microparticles, or biologically modified ceramics (biocers; Bottcher et al., J. Mater. Chem., 2004, 14, 2176-2188). Another aspect of the invention relates to an isolated polynucleotide encoding a polypeptide or chimeric protein of the invention. The synthetic or recombinant polynucleotide may be DNA, RNA or combination thereof, either single- and/or double-stranded. Preferably the polynucleotide comprises a coding sequence which is optimized for the host in which the polypeptide or chimeric protein is expressed. In a preferred embodiment, the polynucleotide comprises or consists of a sequence selected from the group consisting of the sequences SEQ ID NO: 16, 34, 59, 62, 64 and 68. Another aspect of the invention relates to a recombinant vector comprising said polynucleotide. Preferably, said recombinant vector is an expression vector capable of expressing said polynucleotide when transfected or transformed into a host cell such as a eukaryotic or prokaryotic cell like a mammalian, bacterial or fungal cell. The polynucleotide is inserted into the expression vector in proper orientation and correct reading frame for expression. Preferably, the polynucleotide is operably linked to at least one transcriptional regulatory sequence and, optionally to at least one translational regulatory sequence. In a preferred embodiment, the polynucleotide is under the control of a promoter which is upregulated in response to uranium such as for example Caulobacter urc-A promoter (Hillson et al., Applied and Environmental Microbiology, 2007, 73, 7615-7621). Recombinant vectors include usual vectors used in genetic engineering and gene therapy including for example plasmids and viral vectors. Another aspect of the invention provides a host cell or a non-human organism transformed with said polynucleotide or recombinant vector. Preferably, said modified host cell or non-human transgenic organism is resistant to radiations, and/or pollutants such as for example nitrates and toxic metals. The non-human transgenic organism is obtained from a unicellular or pluricellular microorganism or a higher eukaryotic organism. In a preferred embodiment said modified host cell is a prokaryotic cell such as a bacteria. In another embodiment, said non-human transgenic organism is a transgenic plant, nematode, zebrafish or algae. The polynucleotide, vector, cell, and non-human transgenic organism of the invention are useful for the production of the polypeptide/chimeric protein of the invention using well-known recombinant DNA techniques. Another aspect of the invention relates to the use of the polypeptide, fusion protein, host cell, non-human transgenic organism, in vitro or in vivo, as uranyl chelating agent. The chelating agent is useful for the detection, the decontamination, and/or the bioremediation of uranium contamination in an environment (water, soil, effluents, . . . ) or in individuals. The labelled polypeptide/fusion protein such as the polypeptide comprising a fluorescent residue like a tyrosine residue in position 7 of the loop or the cameleon protein, is a uranyl biosensor. It can be used in vitro as uranyl analysis or diagnostic reagent for the detection of uranyl in an environment (water, soil, effluents, . . . ) or in biological samples from individuals (biological fluids, . . . ). In addition, the cameleon protein is also used as cell imaging reagent, diagnostic reagent and bioindicator for the detection of uranyl in situ in modified cells (for example recombinant cells) or non-human transgenic organisms expressing the cameleon protein. The polynucleotide according to the invention is prepared by the conventional methods known in the art. For example, it is produced by amplification of a nucleic sequence by PCR or RT-PCR, by screening genomic DNA libraries by hybridization with a homologous probe, or else by total or partial chemical synthesis. The recombinant vectors are constructed and introduced into host cells by the conventional recombinant DNA and genetic engineering techniques, which are known in the art. The polypeptide/chimeric protein is prepared by the conventional techniques known to those skilled in the art, in particular by solid-phase or liquid-phase synthesis or by expression of a recombinant DNA in a suitable cell system (eukaryotic or prokaryotic). More specifically, the polypeptide can be solid-phase synthesized, according to the Fmoc technique, originally described by Merrifield et al. (J. Am. Chem. Soc., 1964, 85: 2149-), and purified by reverse-phase high performance liquid chromatography; the polypeptide/chimeric protein can be produced from the corresponding cDNAs, obtained by any means known to those skilled in the art; the cDNA is cloned into a eukaryotic or prokaryotic expression vector and the protein produced in the cells modified with the recombinant vector is purified by any suitable means, in particular by affinity chromatography. The practice of the present invention will employ, unless otherwise indicated, conventional techniques which are within the skill of the art. Such techniques are explained fully in the literature. 1. Methods The recombinant peptides were produced in E. coli. A histidine-tag followed by the Tobacco Etch Virus protease (TEV) recognition sequence was introduced at the N-terminus, allowing the purification of the pepti using two subsequent chromatography steps on Ni-columns. 1.1 Engineering and Purification of Calmodulin Derived Peptides The CaM1 construct containing the Arabidopsis thaliana sequence of calmodulin domain 1 was obtained as previously described (Pardoux et al., PLoS One, 2012, 7, e41922) and used as a template for new constructs. The CaM1 construct (nucleotide sequence SEQ ID NO: 39/amino acid sequence SEQ ID NO: 40) comprises the following mutations, by reference to CaM1 amino acid sequence: (1) C28Y mutation to allow the monitoring of uranyl- and calcium-binding and the determination of their binding affinities, by following tyrosine fluorescence emission at 302 nm, (2) T31A and K32A mutations to enable efficient phosphorylation of T30 by CK2, and (3) D58A and D60A mutations to inactivate the metal-binding site 2 of domain 1. To obtain CaMΔ construct (nucleotide sequence SEQ ID NO: 16/amino acid sequence SEQ ID NO: 17), deletions of K23 and D24 were produced with the QuickChange site-directed mutagenesis kit (STRATAGENE) and specific primer pairs DGD S (SEQ ID NO: 41) and DGD AS (SEQ ID NO: 42), according to the manufacturer's instructions. The engineering plasmid was called pQE-CaMΔ. To obtain CaMΔ3 construct (nucleotide sequence SEQ ID NO: 55/amino acid sequence SEQ ID NO: 56), deletion of D24 was produced with the QuickChange site-directed mutagenesis kit (STRATAGENE) and specific primer pairs S-Δ3Y (SEQ ID NO: 57) and AS-Δ3Y (SEQ ID NO: 58), according to the manufacturer's instructions. The engineering plasmid was called pQE-CaMΔ3. We also produced CaMΔ-WT (nucleotide sequence SEQ ID NO: 59/amino acid sequence SEQ ID NO: 60). The protein sequence is the same than those of CaMΔ except that A31 and A32 were replaced by T31 and K32. Recombinant fusion proteins expressed in E. coli strain M15Rep4 (QIAGEN) were grown at 37° C. in LB medium containing ampicillin (50 μg/mL) and kanamycin (50 μg/mL). Expression was induced by addition of 0.1 mM isopropyl-D-thiogalactoside once OD600 reached 0.5, and the cultures were further incubated for 5 h at 37° C. Cellular extracts were obtained by French press lysis and a centrifugation step of 30 min at 15000 rpm, and were applied at a 1 mL/min flow rate on a 5 mL HiTrap Chelating Column (GE HEALTHCARE) in buffer A (50 mM Tris-HCl, 0.5 M NaCl, 25 mM imidazole buffer pH 7.5) containing 1 mM 4-(2-Aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF). The proteins were eluted from the nickel resin at a 4 mL/min flow rate using buffer A supplemented with 150 mM imidazole. The proteins were dialyzed against buffer A and the His-Tags were removed by incubation overnight at 4° C. with TEV protease, followed by separation using a HiTrap Chelating Column. Recombinant proteins were dialyzed against 50 mM Tris-HCl, 150 mM NaCl, pH 7.5. The protein concentrations were measured according to the BC Assay (UPTIMA) with bovine serum albumin as standard. The proteins were concentrated using the Microcon filtration system (Amicon Millipore®), with a cut-off point of 3 kDa. Phosphorylation of the peptide CaMΔ was performed as previously described in Pardoux et al., PLoS One, 2012, 7, e41922. 1.2 Tyrosine Fluorescence Titrations The metal-binding affinity of the various peptides for calcium and uranyl was examined by monitoring the fluorescence intensity of the single tyrosine residue (Tyr28). The uranyl solutions were prepared extemporaneously by diluting a 0.1 M stock solution of uranyl nitrate (pH 3.5, stored frozen at −20° C.) in the final buffer. Fluorescence titrations in the presence of uranyl were performed using a 10 μM peptide solution in MES (20 mM, pH 6) or Tris (20 mM, pH 7) buffer with 100 mM KCl and 100 μM iminodiacetate (IDA). Fluorescence titrations in the presence of calcium were performed in a 10 μM peptide solution in MES (20 mM, pH 6) or Tris (20 mM, pH 7) buffer with 100 mM KCl. To remove any trace of calcium from the samples, each sample solution was incubated 1 h with Chelex®-100 before uranyl or calcium addition. Spectra were collected on a Cary Eclipse spectrofluorimeter at 25° C., with 270 nm excitation. Emission was observed from 290 to 350 nm. The excitation and emission slits were 10 nm. A 15 min equilibration time was respected before each measurement. The reported stability constants are averages of three experimental values. Competition experiments between calmodulin-derived peptides CaM peptides and IDA were performed to determine the conditional dissociation constants of the peptide-uranyl complexes at pH 6 and pH 7. IDA has a moderate affinity for uranyl and forms three major complexes: UO2IDA, [UO2(IDA)2]2−, and [(UO2)2(IDA)2(OH)2]2−. The conditional stability constants of these three species were calculated from the pKas and the stability constants at 25° C. and 0.1 M ionic strength given by Jiang et al. (Inorg. Chem., 2003, 42, 1233-1240). These three conditional stability constants were fixed in the spectral data analysis, which was performed using the program SPECFIT (Binstead et al., Specfit Global Analysis System Version 3.0.34, 2003). Identical values were obtained for the conditional stability constants of the UO2-P complexes (where P stands for peptide), either considering that the UO2-P complex emits or not. In the former case, the spectrum of the UO2-P complex was calculated to be zero, as the fluorescence emission of tyrosine was totally quenched in the complex. For titrations in the presence of calcium, the conditional dissociation constants (Kd) were determined by fitting the difference between fluorescence intensities measured in the presence (F) and in the absence (F0) of calcium, according to a one site saturation model: ΔF=(Fmax×[Ca])/(Kd+[Ca]) using SigmaPlot 10.0 software (Systat Software). In this equation, Fmax corresponds to the maximum of fluorescence determined by the software. 1.3 Exposure of E. coli Cells Producing or not the CaMΔ Peptide to Uranyl Toxicity E. coli cells were grown overnight in LB-MES 100 mM, pH 5.5. The cells where transferred to a LB-glucose (4 g/L) medium at pH 4.5, inoculated at 1/100 volume. IPTG was added at a OD600nm=0.4. After 30 minutes, 50 μM uranyl(acetate)2 or 100 μM Na-acetate was added to the medium. Cell growth was followed by measuring the absorption at 600 nm. 2. Results 2.1 Binding Affinity of the CaMΔ, CaMΔ-WT and CaMΔ3 Peptides for Uranyl The peptides were prepared at a 10 μM concentration in 20 mM MES pH 6 or Tris pH 7, with 0.1 M KCl and 100 μM IDA. Increasing concentrations of uranyl nitrate were added to the peptide solution, until the peptide to uranyl ratio was approximately 1:4. By using this stoichiometric ratio, the protein samples were not affected by uranyl addition (as monitored by UV-Vis absorption), which is crucial for the interpretation of the results. Addition of uranyl nitrate decreased the fluorescence signal emitted by the single tyrosine present in the peptides at position 7 of the metal-binding loop (FIG. 3). Tyrosine fluorescence quenching by uranyl has been reported in the literature for other proteins such as transferrin. Conditional dissociations constants of the peptide—uranyl complexes (Kd) resulting from the competition experiments with IDA were determined at pH 6 and pH 7 for the CaMΔ peptide and at pH 6 for the CaMΔWT and CaMΔ3 peptides. Conditional dissociation constants of 1.8 (±0.5) 10−10 M and 2 (±0.1) 10−10 M were calculated at pH 6 and pH 7 for the CaMΔ—uranyl complex. There is no significant effect of pH on the affinity of the peptide CaMΔ for uranyl. The affinity of the CaMΔ peptide is two orders of magnitude greater than that of the CaM 1 peptide, possessing a 12 amino acid long binding loop, which has a Kd of 25 10−9 M at pH 6 (Pardoux et al., PLoS One, 2012, 7, e41922). Interestingly the peptide CaMΔ3, in which only one aspartate at position 3 of the loop has been deleted, has a much lower affinity for uranyl. A conditional dissociation constant of 130±10 10−9M was obtained for uranyl at pH 6. The affinity of this peptide for uranyl is 722 times lower than that of the CaMΔ peptide. It is also lower than the affinity of CaM1 for uranyl. This experiment demonstrates that it is not sufficient to suppress (at least) one of the aspartate ligands to increase the affinity for uranyl, but that structural factors significantly affect the affinity of the peptide binding loop for uranyl. Finally, a conditional dissociation constant of 2±0.1 10−10M was obtained for the CaMΔ-WT peptide, differing from the CaMΔ peptide by residues at positions 10 and 11 of the metal binding loop (numbering according to the native sequence of 12 AA). A threonine and a lysine are present in this peptide instead of two alanines in the CaMΔ peptide. The affinity for uranyl is equivalent to that of CaMΔ. The phosphorylated peptide CaMΔP presents similar binding affinities for uranyl, with conditional dissociation constants Kd=4 (±0.09) 10−10 M at pH 6 and Kd=1.3 (±0.3) 10−10 M at pH 7. Moreover, both peptides have a very low affinity for calcium. Conditional dissociation constants in the millimolar range were observed for the CaMΔ-Ca2+ complex at pH 6 (Kd>1 mM) and at pH 7 (Kd=8.7 mM). Similar dissociation constants were observed for the phosphorylated peptide CaMΔP with Kd of 7.8 mM at pH 6 and Kd=4.2 mM at pH 7. 2.2 Competition Experiments with Calcium The selectivity of the two peptides (CaMΔ and CaMΔP) for uranyl as compared to calcium is of the order of 107. To check if this selectivity is actually observed in a medium containing both uranyl and calcium, the binding isotherm of uranyl was measured in the presence of 10 mM CaCl2 in the solution. FIG. 4 shows the superimposition of binding thermograms corresponding to Tyr fluorescence quenching (i.e. uranyl binding) in the absence and in the presence of 10 mM CaCl2. These results show that calcium has a very modest effect on uranyl titration. The results of this competition experiment show that these peptides can be used for uranyl detection in the presence of large concentrations of calcium. 2.3 the Expression of the CaMΔ Peptide in E. coli Cells Decreases Uranyl Toxicity to the Cells FIG. 5 shows growth curves recorded with E. coli cells exposed either to 50 μM uranyl acetate, or to 100 μM Na acetate as a control, in LB glucose medium at pH 4.5. Exposure conditions are detailed in the Methods. The FIG. 5 shows that uranyl exposure stops E. coli growth rapidly (full signs as compared to empty signs) except for the cells expressing the CaMΔ peptide. The growth of the cells expressing the CaMΔ peptide is lower than that of the other strains. This may be due to a too strong protein overexpression. However, addition of uranyl didn't affect anymore the growth of this strain. These results suggest that the chelation of uranyl by the CaMΔ peptide protect the whole cells by reducing uranyl toxicity. Conclusions CaMΔ peptide presents an affinity for uranyl in the subnanomolar range and a very high selectivity towards calcium. It is expressed in high quantities in E. coli cells. For these reasons, it is a promising tool for the development of biosensors (in vivo and in vitro) or efficient chelating systems in vitro. The use of the binding loop sequence of CaMΔ for the other sites of calmodulin may not be as efficient for selecting uranyl binding at these sites as at site one. Therefore, structural parameters that could increase the affinity of site 2 toward uranyl as well as its uranyl/calcium specificity were explored using molecular dynamics. Two indicative informations can be obtained using molecular dynamic simulations; the first one concerns the structural model; the second one concerns the stabilisation energy associated with uranyl binding on the protein. The structural models of the Ef-hand2 obtained by molecular dynamics simulations show that uranyl coordination may be efficiently achieved in shorter binding loops, i.e. using deletion of at least two residues (FIG. 10). 1. Methods 1.1 Construction of Expression Vector for Cameleon Biosensors Cloning steps were made with standard methods using XL1Blue cells as E. coli strain. All mutations were made using a QuickChange site-directed mutagenesis kit (Stratagene) and specific primer pairs according to the manufacturer. The gene coding for the cameleon biosensor WT (denoted eCFP-CaM-Linker-M13-eYFP) was constructed in three steps. The gene encoding the wild-type CaM from A. thaliana fused with a linker and the CaM-binding peptide of myosin light-chain kinase (M13) was synthetized by Eurofins MWG and cloned into the pQE30 plasmid (QIAGEN) between Sac I and Sal I restriction sites. Then, the enhanced Cyan Fluorescent Protein (eCFP) gene containing the TEV protease recognition site upstream of the coding sequence of eCFP was PCR-amplified using the S-TEV-eCFP-BamHI (SEQ ID NO: 43) and AS-eCFP-SacI (SEQ ID NO: 44) primers and cloned upstream the CaM-linker-M13 gene, between BamH I and Sac I restriction sites. Finally, the enhanced Yellow Fluorescent Protein (eYFP) was PCR-amplified using the S-eYFP-SalI (SEQ ID NO: 45) and AS-eYFP-HindIII (SEQ ID NO: 46) primers and cloned downstream the CaM-linker-M13 gene, between the Sal I and Hind III restriction sites. Both genes contained no stop codon except for the eYFP gene. The cameleon biosensor WT corresponds to the cDNA of SEQ ID NO: 47 and the protein of SEQ ID NO: 48. The construction of expression vector for the cameleon biosensor Δ was made by using the cameleon biosensor WT gene as a template and primers S-Δ (SEQ ID NO: 49) and AS-Δ (SEQ ID NO: 50). The constructions of expression vectors for the cameleon biosensor WT-S2M or for the cameleon biosensor A-S2M (S2M corresponding to the inactivation of site 2 of the domain 1) were made using as a template the cameleon biosensor WT gene or the cameleon biosensor Δ gene respectively and primers S-S2M (SEQ ID NO: 51) and AS-S2M (SEQ ID NO: 52). The cameleon biosensor Δ corresponds to the cDNA of SEQ ID NO: 34 and the protein of SEQ ID NO: 35. The cameleon biosensor WT-S2M corresponds to the cDNA of SEQ ID NO: 53 and the protein of SEQ ID NO: 54. The cameleon biosensor Δ-S2M corresponds to the cDNA of SEQ ID NO: 36 and the protein of SEQ ID NO: 37. 1.2 Expression of the Cameleon Biosensors The recombinant vectors pQE30 containing the biosensor genes were introduced in the E. coli strain M15Rep4. Recombinant fusion proteins were expressed as follows: the overexpression strain was grown at 37° C. in LB medium containing ampicillin (50 μg/mL) and kanamycin (50 μg/mL) until OD600 reached 0.5. Expression was then induced by addition of 0.1 mM isopropyl-D-thiogalactoside (IPTG) and the cultures were further incubated for 20 h at 17C. Cells were collected by centrifugation 20 min at 5000 rpm, and the bacterial pellet was frozen and stored at −80° C. 1.3 Purification of the Cameleon Biosensors Bacteria were resuspended in buffer A (50 mM Tris-HCl, 0.5 M NaCl, 25 mM imidazole pH 7.5) containing 1 mM 4-(2-Aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF)+15 g/mL DNAse1+30 mM MgSO4. The cellular extracts were obtained by French Press lysis and a centrifugation step of 30 min at 15 000 rpm. The cellular extracts were applied on a 5 mL HiTrap™ Column (GE Healthcare) in buffer A at 1 mL/min flow rate. The proteins were eluted from the nickel resin at 4 mL/min flow rate using an imidazole gradient. The proteins were dialyzed against buffer A and the His-Tags were removed by incubation overnight at 4° C. in presence of the TEV protease followed by separation using HiTrap Chelating Column. Gel Filtration was performed for further purification of the proteins using a 26/600 Superdex 200 column (GE HealthCare) and 50 mM Tris-HCl buffer, pH 7.5, supplemented with 150 mM NaCl. The protein concentrations were measured according to the BC Assay from Uptima with bovine serum albumin as standard. The proteins were concentrated using Microcon® filtration system (Amicon Millipore®, with a cut off of 10 kDa). 1.4 FRET Measurement Fluorescence experiments were performed using an Infinite 1000 (TECAN). Cameleon biosensor WT proteins were first incubated with an excess of ethylenediaminetetraacetic acid (EDTA) and dialyzed overnight against 50 mM Tris-Cl pH 7 containing Chelex® resin. This step is used to remove calcium likely to be present in the different CaM-binding sites. For each measurement, 1 μM of protein was mixed in 200 μL of 50 mM Tris-CI pH 7 buffer (treated with Chelex®) at 25° C. CaCl2 or uranyl nitrate were added at varying concentrations between 0 and 10 μM. Excitation was performed at 440 nm and the emission spectrum recorded between 450 and 570 nm. 2. Results The results obtained with the cameleon biosensor WT protein (FIGS. 6 and 7, the spectra were normalized at 476 nm) show that this biosensor is able to do some FRET in presence of calcium, and that the maximum of FRET is obtained at 8 μM of calcium and above. Similar results are obtained with 8 μM of uranyl nitrate, showing that the cameleon biosensor obtained with the WT calmodulin shows similar sensitivities for calcium and uranyl. This example illustrates the possibility to use peptides derived from calmodulin immobilized on a solid support to chelate uranyl from a solution. 1. Methods The peptide CaMΔ was grafted on a gold strip surface modified by a 5 to 200 nm thick layer of polyacrylic acid, using activation via succinimide esters. A solution of CaMΔ at 100 g/mL in MES buffer 20 mM was used. Stable grafting of the protein was verified by Fourier transform infrared spectroscopy monitoring of the presence of the two amide I and amide II bands characteristic for proteins (FIG. 8). The protein was grafted on one half of the gold strip, the other half being used as a control area to identify possible nonspecific adsorption of uranyl. The interaction with uranyl was performed by a 2 hours dipping in an uranyl chloride solution (in ultrapure water) followed by thorough rinsing with ultrapure water (18 MΩ). X-ray photoelectron spectrometry (XPS) was used to identify the presence of nitrogen and uranyl at the gold strip surface. 2. Results FIG. 8 shows the FTIR transmission spectra recorded with the gold strip covered either with the polyacrylic acid alone (middle spectrum) or with protein grafted to polyacrylic acid layers of 5 nm (upper spectrum) and 50 nm (lower spectrum). The bands at 1673 and 1555 cm−1 are representative of the presence of the protein. These bands are observed in the upper and lower spectra. They are more intense in the lower spectrum, showing the impact of the polyacrylic layer thickness on the protein load onto the gold strip. These data show that CaMΔ was successfully grafted onto the gold strip. FIG. 9 shows the XPS spectra recorded on the gold strip: the upper spectrum was recorded at a spot containing protein and the lower spectrum was recorded on a spot corresponding to the gold strip without protein. The band at ˜382.5 eV corresponds to the presence of nitrogen, while the bands at ˜394 eV and 401 eV correspond to the presence of uranium. The presence of uranium is only observed concomitant to the presence of nitrogen (upper spectrum), indicating that uranyl is immobilized by the protein. These results show that specific uranyl adsorption by CaMΔ occurs when CaMΔ is immobilized on a solid metal support. These results show that CaMΔ may be used for uranyl chelation from water, for depollution applications. TABLEAmino acid and nucleotide sequencesNameSequenceSEQ ID NO: 1ArabidopsisATGGCGGATCAGCTCACCGACGATCAGATCTCTGAGTTTAAthaliana CaM3GGAAGCTTTCAGCTTATTCGACAAGGATGGTGATGGTTGCATTACCACCAAGGAGCTGGGTACTGTGATGCGTTCCCTTGGACAAAACCCAACCGAAGCAGAGCTTCAAGACATGATCAACGAAGTGGATGCTGATGGTAACGGTACCATTGATTTCCCAGAGTTCTTGAACCTTATGGCTCGTAAGATGAAGGACACCGACTCTGAGGAAGAGCTCAAGGAAGCATTCCGGGTTTTCGACAAGGACCAGAACGGTTTCATCTCAGCAGCTGAGCTCCGCCATGTGATGACAAACCTTGGCGAGAAGCTTACTGATGAAGAAGTTGATGAGATGATCAAGGAAGCTGATGTTGATGGTGATGGTCAGATTAACtACGAAGAGTTTGTTAAGGTCATGATGGCTAAGTGACT SEQ ID NO: 2ArabidopsisMADQLTDDQISEFKEAFSLFDKDGDGCITTKELGTVMRSLGthaliana CaM3QNFTEAELQDMINEVDADGNGTIDEPEFLNLMARKMKDTDSEEELKEAFRVFDKDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADVDGDGQINYEEFVKVMMAK SEQ ID NO: 3CaM3 EF-hand1 loopDKDGDGCITTKE SEQ ID NO: 4CaM3 EF-hand2 loopDADGNGTIDFPE SEQ ID NO: 5CaM3 EF-hand3 loopDKDQNGFISAAE SEQ ID NO: 6CaM3 EF-hand4 loopDVDGDGQINYEE SEQ ID NO: 7EF-hand1 loop DGDGCITTKEΔK2D3/ΔD1K2 SEQ ID NO: 8EF-hand1 loop DGDGYITTKEΔK2D3/ΔD1K2 + C7Y SEQ ID NO: 9EF-hand1 loop DGDGYITAAEΔK2D3/ΔD1K2 +C7Y + T10A + K11A SEQ ID NO: 10EF-hand2 loopDGNGTIDFPEΔA2D3/ΔD1A2 SEQ ID NO: 11EF-hand2 loopDGNGYIDFPEΔA2D3/ΔD1A2 + T7Y SEQ ID NO: 12EF-hand2 loopDGDGTIDFPEΔA2D3/ΔD1A2 + N5D SEQ ID NO: 13EF-hand2 loopDGDGYIDFPEΔA2D3/ΔD1A2 +T7Y + N5D SEQ ID NO: 14EF-hand3 loopDQNGFISAAEΔK2D3/ΔD1K2 SEQ ID NO: 15EF-hand4 loopDGDGQINYEEΔV2D3/ΔD1V2 SEQ ID NO: 16CaMΔTCC ATG GCG GAT CAG CTC ACC GAC GAT CAGATC TCT GAG TTT AAG GAA GCT TTC AGC TTATTC GAC GGT GAT GGT TaC ATT ACC GCC GCGGAG CTG GGT ACT GTG ATG CGT TCC CTT GGACAA AAC CCA ACC GAA GCA GAG CTT CAA GACATG ATC AAC GAA GTG GcT GCT GcT GGT AACGGT ACC ATT GAT TTC CCA GAG TTC TTG AACCTT ATG GCT CGT AAG TGA SEQ ID NO: 17CaMΔSMADQLTDDQISEFKEAFSLEDGDGYITAAELGTVMRSLGQNPTEAELQDMINEVAAAGNGTIDEPEFLNLMARK SEQ ID NO: 18Calmodulin variantMADQLTDDQISEFKEAFSLEDGDGCITTKELGTVMRSLGQNfrom CameleonPTEAELQDMINEVDADGNGTIDEPEFLNLMARKMKDTDSEEbiosensor ΔELKEAFRVFDKDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADVDGDGQINYEEFVKVMMAK SEQ ID NO: 19Calmodulin variantMADQLTDDQISEFKEAFSLFDGDGCITTKELGTVMRSLGQNfrom CameleonPTEAELQDMINEVAAAGNGTIDEPEFLNLMARKMKDTDSEEbiosensor Δ-S2MELKEAFRVFDKDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADVDGDGQINYEEFVKVMMAK SEQ ID NO: 20Calmodulin variantMADQLTDDQISEFKEAFSLFDGDGCITTKELGTVMRSLGQN(Δ sites PTEAELQDMINEVDGNGTIDFPEFLNLMARKMKDTDSEEEL1, 2, 3, 4)KEAFRVFDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADGDGQINYEEFVKVMMAK SEQ ID NO: 21M13AAACGTCGCTGGCTTTATTGCGGTGAGCGCGGCCAACCGCTTTAAAAAAATTAGCTCGAGCGGCGCGCTG SEQ ID NO: 22M13KRRWKKNFIAVSAANRFKKISSSGAL SEQ ID NO: 23skMLCKKRRWKKNFIAVSAANRFKKISSSGA SEQ ID NO: 24MLCKpRRKWQKTGHAVRAIGRL SEQ ID NO: 25smMLCKARRKWQKTGHAVRAIGRLSS SEQ ID NO: 26wasp venomVNWKKIGQHILSV SEQ ID NO: 27p21KRRQTSMTDFYHSKRRLIFSKRKP SEQ ID NO: 28melittinQQRKRKIWSILAPLGTTLVKLVAGIG SEQ ID NO: 29spectrinKTASPWKSARLMVTIVATENSIKE SEQ ID NO: 30CaMKIAKSKWKQAFNATAVVRHMRKLQ SEQ ID NO: 31CaMKIILKKFNARRKLKGAILTTMLATRNFS SEQ ID NO: 32CaMKKRFPNGFRKRHGMAKVLILTDLRPIRRV SEQ ID NO: 33peptidelLKWKKLLKLLKKLLKLG SEQ ID NO: 34CameleonTCCATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTbiosensor ΔGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAGGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCCTGACCTGGGGCGTGCAGTGCTTCAGCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGTACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACATCAGCCACAACGTCTATATCACCGCCGACAAGCAGAAGAACGGCATCAAGGCCCACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCACCCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGAGCTCATGGCGGATCAGTTGACCGACGATCAGATCTCTGAATTTAAGGAAGCCTTCAGCTTATTCGACGGTGATGGTTGCATTACCACCAAGGAACTGGGTACTGTGATGCGTTCCCTGGGCCAAAACCCGACCGAAGCAGAGCTGCAAGACATGATCAACGAAGTGGATGCGGATGGTAACGGTACCATTGATTTCCCGGAATTCTTGAACCTGATGGCCCGTAAGATGAAAGACACCGACAGCGAGGAAGAGCTGAAAGAAGCCTTCCGCGTTTTCGACAAAGACCAGAACGGTTTCATCAGCGCAGCGGAACTGCGCCATGTGATGACCAACCTGGGCGAAAAACTGACGGATGAAGAAGTTGATGAGATGATCAAAGAAGCGGATGTGGATGGTGATGGTCAGATTAACTACGAAGAGTTTGTTAAGGTGATGATGGCGAAAGGCGGTGGCGGTAGCAAACGTCGCTGGAAAAAAAACTTTATTGCGGTGAGCGCGGCCAACCGCTTTAAAAAAATTAGCTCGAGCGGCGCGCTGGTCGACATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAAGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCTTCGGCTACGGCGTGCAGTGCTTCGCCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGCACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACAACAGCCACAACGTCTATATCATGGCCGACAAGCAGAAGAACGGCATCAAGGTGAACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCTACCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGGGATCACTCTCGGCATGGACGAGCTGTACAAGTAA SEQ ID NO: 35CameleonSMVSKGEELFTGVVPILVELDGDVNGHRFSVSGEGEGDATYbiosensor ΔGKLTLKFICTTGKLPVPWPTLVTTLTWGVQCFSRYPDHMKQHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYISHNVYITADKQKNGIKAHFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSTQSALSKDPNEKRDHMVLLEFVTAAELMADQLTDDQISEFKEAFSLEDGDGCITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTIDFPEFLNLMARKMKDTDSEEELKEAFRVFDKDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADVDGDGQINYEEFVKVMMAKGGGGSKRRWKKNFIAVSAANRFKKISSSGALvdMVSKGEELFTGVVPILVELDGDVNGHKESVSGEGEGDATYGKLTLKFICTTGKLPVPWPTLVTTFGYGVQCFARYPDHMKQHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYNSHNVYIMADKQKNGIKVNFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSYQSALSKDPNEKRDHMVLLEFVTAAGITLGMDELYK SEQ ID NO: 36CameleonTCCATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTbiosensorGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAΔ-S2MGGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCCTGACCTGGGGCGTGCAGTGCTTCAGCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGTACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACATCAGCCACAACGTCTATATCACCGCCGACAAGCAGAAGAACGGCATCAAGGCCCACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCACCCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGAGCTCATGGCGGATCAGTTGACCGACGATCAGATCTCTGAATTTAAGGAAGCCTTCAGCTTATTCGACGGTGATGGTTGCATTACCACCAAGGAACTGGGTACTGTGATGCGTTCCCTGGGCCAAAACCCGACCGAAGCAGAGCTGCAAGACATGATCAACGAAGTGGCTGCGGCTGGTAACGGTACCATTGATTTCCCGGAATTCTTGAACCTGATGGCCCGTAAGATGAAAGACACCGACAGCGAGGAAGAGCTGAAAGAAGCCTTCCGCGTTTTCGACAAAGACCAGAACGGTTTCATCAGCGCAGCGGAACTGCGCCATGTGATGACCAACCTGGGCGAAAAACTGACGGATGAAGAAGTTGATGAGATGATCAAAGAAGCGGATGTGGATGGTGATGGTCAGATTAACTACGAAGAGTTTGTTAAGGTGATGATGGCGAAAGGCGGTGGCGGTAGCAAACGTCGCTGGAAAAAAAACTTTATTGCGGTGAGCGCGGCCAACCGCTTTAAAAAAATTAGCTCGAGCGGCGCGCTGGTCGACATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAAGTTCAGCGTGTCOGGCGAGGGCGAGGGCGATGOCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCTTCGGCTACGGCGTGCAGTGCTTCGCCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGCACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACAACAGCCACAACGTCTATATCATGGCCGACAAGCAGAAGAACGGCATCAAGGTGAACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCTACCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGGGATCACTCTCGGCATGGACGAGCTGTACAAGTAA SEQ ID NO: 37CameleonSMVSKGEELFTGVVPILVELDGDVNGHRFSVSGEGEGDATYbiosensorGKLTLKFICTTGKLPVPWPTLVTTLTWGVQCFSRYPDHMKQΔ-S2MHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYISHNVYITADKQKNGIKAHFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSTQSALSKDPNEKRDHMVLLEFVTAAELMADQLTDDQISEFKEAFSLFDGDGCITTKELGTVMRSLGQNPTEAELQDMINEVAAAGNGTIDEPEFLNLMARKMKDTDSEEELKEAFRVEDKDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADVDGDGQINYEEFVKVMMAKGGGGSKRRWKKNFIAVSAANRFKKISSSGALvdMVSKGEELFTGVVPILVELDGDVNGHKESVSGEGEGDATYGKLTLKFICTTGKLPVPWPTLVTTFGYGVQCFARYPDHMKQHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYNSHNVYIMADKQKNGIKVNFKIRHNIEDGSVQLADHYQQNTFIGDGPVLLPDNHYLSYQSALSKDPNEKRDHMVLLEFVTAAGITLGMDELYK SEQ ID NO: 38CameleonSMVSKGEELFTGVVPILVELDGDVNGHRFSVSGEGEGDATYbiosensorGKLTLKFICTTGKLPVPWPTLVTTLTWGVQCFSRYPDHMKQΔΔΔΔHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYISHNVYITADKQKNGIKAHFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSTQSALSKDPNEKRDHMVLLEFVTAAELMADQLTDDQISEFKEAFSLEDGDGCITTKELGTVMRSLGQNPTEAELQDMINEVDGNGTIDEPEFLNLMARKMKDTDSEEELKEAFRVEDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADGDGQINYEEFVKVMMAKGGGGSKRRWKKNFIAVSAANRFKKISSSGALvdMVSKGEELFTGVVPILVELDGDVNGHKFSVSGEGEGDATYGKLTLKFICTTGKLPVPWPTLVTTEGYGVQCFARYPDHMKQHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYNSHNVYIMADKQKNGIKVNFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSYQSALSKDPNEKRDHMVLLEFVTAAGITLGMDELYK SEQ ID NO: 39CaM1TCC ATG GCG GAT CAG CTC ACC GAC GAT CAGATC TCT GAG TTT AAG GAA GCT TTC AGC TTATTC GAC AAG GAT GGT GAT GGT TaC ATT ACCGCC GCG GAG CTG GGT ACT GTG ATG CGT TCCCTT GGA CAA AAC CCA ACC GAA GCA GAG CTTCAA GAC ATG ATC AAC GAA GTG GcT GCT GcTGGT AAC GGT ACC ATT GAT TTC CCA GAG TTCTTG AAC CTT ATG GCT CGT AAG TGA SEQ ID NO: 40CaM1SMADQLTDDQISEFKEAFSLFDKDGDGYITAAELGTVMRSLGQNPTEAELQDMINEVAAAGNGTIDFPEFLNLMARK SEQ ID NO: 41Primer DGD SGAAGCTTTCAGCTTATTCGACGGTGATGGTTACATTACCGCCGCG SEQ ID NO: 42Primer DGD ASCGCGGCGGTAATCTAACCATCACCGTCGAATAAGCTGAAAGCTTC SEQ ID NO: 43PrimerGAGA GGATCC GAG AAC CTG TAC TTC CAG TCCS-TEV-eCFP-BamHIATG GTG AGC AAG GGC GAG GAG SEQ ID NO: 44PrimerTAAA GAGCTC GGCGGCGGTCACGAACTCCAGCAAS-eCFP-SacI SEQ ID NO: 45PrimerTATA GTCGAC ATG GTG AGC AAG GGC GAG GAGS-eYFP-SalI SEQ ID NO: 46PrimerGGGC AAGCTT TTA CTT GTA CAG CTC GTC CATAS-eYFP-HindIIIGCC G SEQ ID NO: 47CameleonTCCATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTbiosensorGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAWTGGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCCTGACCTGGGGCGTGCAGTGCTTCAGCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGTACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACATCAGCCACAACGTCTATATCACCGCCGACAAGCAGAAGAACGGCATCAAGGCCCACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCACCCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGAGCTCATGGCGGATCAGTTGACCGACGATCAGATCTCTGAATTTAAGGAAGCCTTCAGCTTATTCGACAAAGATGGTGATGGTTGCATTACCACCAAGGAACTGGGTACTGTGATGCGTTCCCTGGGCCAAAACCCGACCGAAGCAGAGCTGCAAGACATGATCAACGAAGTGGATGCGGATGGTAACGGTACCATTGATTTCCCGGAATTCTTGAACCTGATGGCCCGTAAGATGAAAGACACCGACAGCGAGGAAGACCTGAAACAAGCCTTCCGCGTTTTCGACAAAGACCAGAACGGTTTCATCAGCGCAGCGGAACTGCGCCATGTGATGACCAACCTGGGCGAAAAACTGACGGATGAAGAAGTTGATGAGATGATCAAAGAAGCGGATGTGGATGGTGATGGTCAGATTAACTACGAAGAGTTTGTTAAGGTGATGATGGCGAAAGGCGGTGGCGGTAGCAAACGTCGCTGGAAAAAAAACTTTATTGCGGTGAGCGCGGCCAACCGCTTTAAAAAAATTAGCTCGAGCGGCGCGCTGGTCGACATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAAGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCTTCGGCTACGGCGTGCAGTGCTTCGCCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGCACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACAACAGCCACAACGTCTATATCATGGCCGACAAGCAGAAGAACGGCATCAAGGTGAACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCTACCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGGGATCACTCTCGGCATGGACGAGCTGTACAAGTAA SEQ ID NO: 48CameleonSMVSKGEELFTGVVPILVELDGDVNGHRFSVSGEGEGDATYbiosensorGKLTLKFICTTGKLPVPWPTLVTTLTWGVQCFSRYTDHMKQWTHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDEKEDGNILGHKLEYNYISHNVYITADKQKNGIKAHEKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSTQSALSKDPNEKRDHMVLLEFVTAAELMADQLTDDQISEFKEAFSLFDKDGDGCITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTIDEPEFLNLMARKMKDTDSEEELKEAFRVEDKDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADVDGDGQINYEEFVKVMMAKGGGGSKRRWKKNFIAVSAANRFKKISSSGALvdMVSKGEELFTGVVPILVELDGDVNGHKESVSGEGEGDATYGKLTLKFICTTGKLPVPWPTLVTTEGYGVQCFARYPDHMKQHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYNSHNVYIMADKQKNGIKVNFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSYQSALSKDPNEKRDHMVLLEFVTAAGITLGMDYK SEQ ID NO: 49Primer S-ΔGGAAGCCTTCAGCTTATTCGACGGTGATGGTTGCATTACC SEQ ID NO: 50Primer AS-ΔGGTAATGCAACCATCACCGTCGAATAAGCTGAAGGCTTCC SEQ ID NO: 51Primer S-S2MGGT ACC GTT ACC AGC AGC AGC CAC TTC GTTGAT C SEQ ID NO: 52Primer AS-S2MGAT CAA CGA AGT GGC TGC TGC TGG TAA CGGTAC C SEQ ID NO: 53CameleonTCCATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTbiosensorGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAWT-S2MGGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCCTGACCTGGGGCGTGCAGTGCTTCAGCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGTACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACATCAGCCACAACGTCTATATCACCGCCGACAAGCAGAAGAACGGCATCAAGGCCCACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCACCCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGAGCTCATGGCGGATCAGTTGACCGACGATCAGATCTCTGAATTTAAGGAAGCCTTCAGCTTATTCGACAAAGATGGTGATGGTTGCATTACCACCAAGGAACTGGGTACTGTGATGCGTTCCCTGGGCCAAAACCCGACCGAAGCAGAGCTGCAAGACATGATCAACGAAGTGGCTGCGGCTGGTAACGGTACCATTGATTTCCCGGAATTCTTGAACCTGATGGCCCGTAAGATGAAAGACACCGACAGCGAGGAAGAGCTGAAAGAAGCCTTCCGCGTTTTCGACAAAGACCAGAACGGTTTCATCAGCGCAGCGGAACTGCGCCATGTGATGACCAACCTGGGCGAAAAACTGACGGATGAAGAAGTTGATGAGATGATCAAAGAAGCGGATGTGGATGGTGATGGTCAGATTAACTACGAAGAGTTTGTTAAGGTGATGATGGCGAAAGGCGGTGGCGGTAGCAAACGTCGCTGGAAAAAAAACTTTATTGCGGTGAGCGCGGCCAACCGCTTTAAAAAAATTAGCTCGAGCGGCGCGCTGGTCGACATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGOTGOTGCCCATCCTGOTCGAGCTGGACGGCGACGTAAACGGCCACAAGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCTTCGGCTACGGCGTGCAGTGCTTCGCCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGCACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACAACAGCCACAACGTCTATATCATGGCCGACAAGCAGAAGAACGGCATCAAGGTGAACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCTACCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGGGATCACTCTCGGCATGGACGAGCTGTACAAGTAA SEQ ID NO: 54CameleonSMVSKGEELFTGVVPILVELDGDVNGHRFSVSGEGEGDATYbiosensorGKLTLKFICTTGKLPVPWPTLVTTLTWGVQCFSRYPDHMKQWT-S2MHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYISHNVYITADKQKNGIKAHFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSTQSALSKDPNEKRDHMVLLEFVTAAELMADQLTDDQISEFKEAFSLFDKDGDGCITTKELGTVMRSLGQNPTEAELQDMINEVAAAGNGTIDEPEFLNLMARKMKDTDSEEELKEAFRVEDKDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADVDGDGQINYEEFVKVMMAKGGGGSKRRWKKNFIAVSAANRFKKISSSGALvdMVSKGEELFTGVVPILVELDGDVNGHKESVSGEGEGDATYGKLTLKFICTTGKLPVPWPTLVTTEGYGVQCFARYPDHMKQHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDEKEDGNILGHKLEYNYNSHNVYTMADKQKNGIKVNFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLFTNHYLSYQSALSKDPNEKRDHMVLLEFVTAAGITLGMDELYK SEQ ID NO: 55CaMΔ3TCC ATG GCG GAT CAG CTC ACC GAC GAT CAGATC TCT GAG TTT AAG GAA GCT TTC AGC TTATTC GAC AAG GGT GAT GGT TaC ATT ACC GCCGCG GAG CTG GGT ACT GTG ATG CGT TCC CTTGGA CAA AAC CCA ACC GAA GCA GAG CTT CAAGAC ATG ATC AAC GAA GTG GcT GCT GcT GGTAAC GGT ACC ATT GAT TTC CCA GAG TTC TTGAAC CTT ATG GCT CGT AAG TGA SEQ ID NO: 56CaMΔ3SMADQLTDDQISEFKEAFSLFDKGDGYITAAELGTVMRSLGQNPTEAELQDMINEVAAAGNGTIDEPEFLNLMARK SEQ ID NO: 57Primer S-Δ3YTTCAGCTTATTCGACAAGGGTGATGGTTACATTACC SEQ ID NO: 58Primer AS-Δ3YGGTAATGTAACCATCACCCTTGTCGAATAAGCTGAA SEQ ID NO: 59CaMΔ-WTTCC ATG GCG GAT CAG CTC ACC GAC GAT CAGATC TCT GAG TTT AAG GAA GCT TTC AGC TTATTC GAC GGT GAT GGT TaC ATT ACC ACC AAGGAG CTG GGT ACT GTG ATG CGT TCC CTT GGACAA AAC CCA ACC GAA GCA GAG CTT CAA GACATG ATC AAC GAA GTG GcT GCT GcT GGT AACGGT ACC ATT GAT TTC CCA GAG TTC TTG AACCTT ATG GCT CGT AAG TGA SEQ ID NO: 60CaMΔ-WTSMADQLTDDQISEFKEAFSLFDGDGYITTKELGTVMRSLGQNPTEAELQDMINEVAAAGNGTIDEPEFLNLMARK SEQ ID NO: 61CameleonSMVSKGEELFTGVVPILVELDGDVNGHRFSVSGEGEGDATYBiosensorGKLTLKFICTTGKLPVPWPTLVTTLTWGVQCFSRYPDHMKQΔ1 Δ3HDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYISHNVYITADKQKNGIKAHFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSTQSALSKDPNEKRDHMVLLEFVTAAelMADQLTDDQISEFKEAFSLEDGDGCITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTIDEPEFLNLMARKMKDTDSEEELKEAFRVEDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADVDGDGQINYEEFVKVMMAKGGGGSKRRWKKNFIAVSAANRFKKISSSGALvdMVSKGEELFTGVVPILVELDGDVNGHKESVSGEGEGDATYGKLTLKFICTTGKLPVPWPTLVTTEGYGVQCFARYPDHMKQHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYNSHNVYIMADKQKNGIKVNFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSYQSALSKDPNEKRDBMVLLEFVTAAGITLGMDELYK SEQ ID NO: 62CameleonTCCATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTBiosensorGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAΔ1 Δ3GGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCCTGACCTGGGGCGTGCAGTGCTTCAGCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGTACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACATCAGCCACAACGTCTATATCACCGCCGACAAGCAGAAGAACGGCATCAAGGCCCACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCACCCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGAGCTCATGGCGGATCAGTTGACCGACGATCAGATCTCTGAATTTAAGGAAGCCTTCAGCTTATTCGACGGTGATGGTTGCATTACCACCAAGGAACTGGGTACTGTGATGCGTTCCCTGGGCCAAAACCCGACCGAAGCAGAGCTGCAAGACATGATCAACGAAGTGGATGCGGATGGTAACGGTACCATTGATTTCCCGGAATTCTTGAACCTGATGGCCCGTAAGATGAAAGACACCGACAGCGAGGAAGAGCTGAAAGAAGCCTTCCGCGTTTTCGACCAGAACGGTTTCATCAGCGCAGCGGAACTGCGCCATGTGATGACCAACCTGGGCGAAAAACTGACGGATGAAGAAGTTGATGAGATGATCAAAGAAGCGGATGTGGATGGTGATGGTCAGATTAACTACGAAGAGTTTGTTAAGGTGATGATGGCGAAAGGCGGTGGCGGTAGCAAACGTCGCTGGAAAAAAAACTTTATTGCGGTGAGCGCGGCCAACCGCTTTAAAAAAATTAGCTCGAGCGGCGCGCTGGTCGACATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAAGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCTTCGGCTACGGCGTGCAGTGCTTCGCCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGCACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACAACAGCCACAACGTCTATATCATGGCCGACAAGCAGAAGAACGGCATCAAGGTGAACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCTACCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGGGATCACTCTCGGCATGGACGAGCTGTACAAGTAA SEQ ID NO: 63CameleonSMVSKGEELFTGVVPILVELDGDVNGHRFSVSGEGEGDATYBiosensorGKLTLKFICTTGKLPVPWPTLVTTLTWGVQCFSRYPDHMKQΔ1 Δ2 Δ3HDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYISHNVYITADKQKNGIKAHFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLFTNHYLSTQSALSKDPNEKRDHMVLLEFVTAAelMADQLTDDQISEFKEAFSLFDGDGCITTKELGTVMRSLGQNPTEAELQDMINEVDGNGTIDFPEFLNLMARKMKDTDSEEELKEAFRVFDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADVDGDGQINYEEFVKVMMAKGGGGSKRRWKKNFIAVSAANRFKKISSSGALvdMVSKGEELFTGVVPILVELDGDVNGHKFSVSGEGEGDATYGKLTLKFICTTGKLPVPWPTLVTTEGYGVQCFARYPDHMKQHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDEKEDGNILGHKLEYNYNSHNVYIMADKQKNGIKVNEKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSYQSALSKDPNEKRDHMVLLEFVTAAGITLGMDELYK SEQ ID NO: 64CameleonTCCATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTBiosensorGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAΔ1 Δ2 Δ3GGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCCTGACCTGGGGCGTGCAGTGCTTCAGCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGTACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACATCAGCCACAACGTCTATATCACCGCCGACAAGCAGAAGAACGGCATCAAGGCCCACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCACCCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGAGCTCATGGCGGATCAGTTGACCGACGATCAGATCTCTGAATTTAAGGAAGCCTTCAGCTTATTCGACGGTGATGGTTGCATTACCACCAAGGAACTGGGTACTGTGATGCGTTCCCTGGGCCAAAACCCGACCGAAGCAGAGCTGCAAGACATGATCAACGAAGTGGATGGTAACGGTACCATTGATTTCCCGGAATTCTTGAACCTGATGGCCCGTAAGATGAAAGACACCGACAGCGAGGAAGAGCTGAAAGAAGCCTTCCGCGTTTTCGACCAGAACGGTTTCATCAGCGCAGCGGAACTGCGCCATGTGATGACCAACCTGGGCGAAAAACTGACGGATGAAGAAGTTGATGAGATGATCAAAGAAGCGGATGTGGATGGTGATGGTCAGATTAACTACGAAGAGTTTGTTAAGGTGATGATGGCGAAAGGCGGTGGCGGTAGCAAACGTCGCTGGAAAAAAAACTTTATTGCGGTGAGCGCGGCCAACCGCTTTAAAAAAATTAGCTCGAGCGGCGCGCTGGTCGACATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAAGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCTTCGGCTACGGCGTGCAGTGCTTCGCCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGCACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACAACAGCCACAACGTCTATATCATGGCCGACAAGCAGAAGAACGGCATCAAGGTGAACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCTACCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGGGATCACTCTCGGCATGGACGAGCTGTACAAGTAA SEQ ID NO: 65CameleonSMVSKGEELFTGVVPILVELDGDVNGHRFSVSGEGEGDATYBiosensorGKLTLKFICTTGKLPVPWPTLVTTLTWGVQCFSRYPDHMKQN-terHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYISHNVYITADKQKNGIKAHFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSTQSALSKDPNEKRDHMVLLEFVTAAelpMADQLTDDQISEFKEAFSLFDKDGDGCITTKELGTVMRSLGQNPTEAELQDMINEVDADGNGTIDEPEFLNLMARKpvdMVSKGEELFTGVVPILVELDGDVNGHKFSVSGEGEGDATYGKLTLKFICTTGKLPVPWPTLVTTEGYGVQCFARYPDHMKQHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDEKEDGNILGHKLEYNYNSHNVYIMADKQKNGIKVNFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSYQSALSKDPNEKRDHMVLLEFVTAAGITLGMDELYK SEQ ID NO: 66CameleonTCCATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTBiosensorGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAN-terGGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCCTGACCTGGGGCGTGCAGTGCTTCAGCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGTACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACATCAGCCACAACGTCTATATCACCGCCGACAAGCAGAAGAACGGCATCAAGGCCCACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCACCCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGAGCTCccgATGGCGGATCAGTTGACCGACGATCAGATCTCTGAATTTAAGGAAGCCTTCAGCTTATTCGACAAGGATGGTGATGGTTGCATTACCACCAAGGAACTGGGTACTGTGATGCGTTCCCTGGGCCAAAACCCGACCGAAGCAGAGCTGCAAGACATGATCAACGAAGTGGATGCGGATGGTAACGGTACCATTGATTTCCCGGAATTCTTGAACCTGATGGCCCGTAAGccgGTCGACATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAAGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCTTCGGCTACGGCGTGCAGTGCTTCGCCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGCACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACAACAGCCACAACGTCTATATCATGGCCGACAAGCAGAAGAACGGCATCAAGGTGAACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCTACCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGGGATCACTCTCGGCATGGACGAGCTGTACAAGTAA SEQ ID NO: 67CameleonSMVSKGEELFTGVVPILVELDGDVNGHRFSVSGEGEGDATYBiosensorGKLTLKFICTTGKLPVPWPTLVTTLTWGVQCFSRYPDHMKQΔ1 Δ2HDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYISHNVYITADKQKNGIKAHFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSTQSALSKDPNEKRDHMVLLEFVTAAELMADQLTDDQISEFKEAFSLEDGDGCITTKELGTVMRSLGQNPTEAELQDMINEVDGNGTIDFPEFLNLMARKMKDTDSEEELKEAFRVFDKDQNGFISAAELRHVMTNLGEKLTDEEVDEMIKEADVDGDGQINYEEFVKVMMAKGGGGSKRRWKKNFIAVSAANRFKKISSSGALVDMVSKGEELFTGVVPILVELDGDVNGHKFSVSGEGEGDATYGKLTLKFICTTGKLPVPWPTLVTTFGYGVQCFARYPDHMKQHDFFKSAMPEGYVQERTIFFKDDGNYKTRAEVKFEGDTLVNRIELKGIDFKEDGNILGHKLEYNYNSHNVYIMADKQKNGIKVNFKIRHNIEDGSVQLADHYQQNTPIGDGPVLLPDNHYLSYQSALSKDPNEKRDHMVLLEFVTAAGITLGMDELYK SEQ ID NO: 68CameleonTCCATGGTGAGCAAGGGCGAGGAGCTGTTCACCGGGGTGGTBiosensorGCCCATCCTGGTCGAGCTGGACGGCGACGTAAACGGCCACAΔ1 Δ2GGTTCAGCGTGTCCGGCGAGGGCGAGGGCGATGCCACCTACGGCAAGCTGACCCTGAAGTTCATCTGCACCACCGGCAAGCTGCCCGTGCCCTGGCCCACCCTCGTGACCACCCTGACCTGGGGCGTGCAGTGCTTCAGCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCATGCCCGAAGGCTACGTCCAGGAGCGTACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGGTGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACATCAGCCACAACGTCTATATCACCGCCGACAAGCAGAAGAACGGCATCAAGGCCCACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCACCCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGOTCCTGCTGGAGTTCGTGACCGCCGCCGAGCTCATGGCGGATCAGTTGACCGACGATCAGATCTCTGAATTtaAGGAAGCCTTCAGCTTATTCGACGGTGATGGTTGCATTACCACCAAGGAACTGGGTACTGTGATGCGTTCCCTGGGCCAAAACCCGACCGAAGCAGAGCTGCAAGACATGATCAACGAAGTGGATGGTAACGGTACCATTGATTTCCCGGAATTCTTGAACCTGATGGCCCGTAAGATGAAAGACACCGACAGCGAGGAAGAGCTGAAAGAAGCCTTCCGCGTTTTCGACAAAGACCAGAACGGTTTCATCAGCGCAGCGGAACTGCGCCATGTGATGACCAACCTGGGCGAAAAACTGACGGATGAAGAAGTTGATGAGATGATCAAAGAAGCGGATGTGGATGGTGATGGTCAGATTAACTACGAAGAGTTTGTTAAGGTGATGATGGCGAAAGGCGGTGGCGGTAGCAAACGTCGCTGGAAAAAAAaCTTTATTGCGGTGAGCGCGGCCAACCGCTTTAAAAAAATTAGCTCGAGCGGCGCGCTGGTCGACAtggtGAGCAAGGGCgaggagcTGtTCACCGGGgtggtgCCCATCctggtCGAgctgGaCGGCGAcgtAAACGGCCACAagtTCAGcgtgTCCGGCgAGGGCgagGGCGatgCCAcCTACGGCAAGCTgaCCcTGAAGTTCATCTGCACCACCGGCAAGCTGCCCgtGCCctgGCCCACCCTcgtgaCCACCTTCGGCtACGGCgtGCAgtgCtTCGCCCGCTACCCCGACCACATGAAGCAGCACGACTTCTTCAAGTCCGCCAtgCCCGAAGGCTACGTCCAGGAGCGCACCATCTTCTTCAAGGACGACGGCAACTACAAGACCCGCGCCGAGGTGAAGTTCGAGGGCGACACCCTGgtGAACCGCATCGAGCTGAAGGGCATCGACTTCAAGGAGGACGGCAACATCCTGGGGCACAAGCTGGAGTACAACTACAACAGCCACAACGTCTATATCATGGCCGACAAGCAGAAGAACGGCATCAAGGTGAACTTCAAGATCCGCCACAACATCGAGGACGGCAGCGTGCAGCTCGCCGACCACTACCAGCAGAACACCCCCATCGGCGACGGCCCCGTGCTGCTGCCCGACAACCACTACCTGAGCTACCAGTCCGCCCTGAGCAAAGACCCCAACGAGAAGCGCGATCACATGGTCCTGCTGGAGTTCGTGACCGCCGCCGGGATCacTCTCGGCATGGACgaGCTGTACAAGTAA SEQ ID NO: 69EF-hand1 loop +DKDGDGYITAAEC7Y + T10A + K11A SEQ ID NO: 70EF-hand1 loopKDGDGCITKEΔD1T10 SEQ ID NO: 71EF-hand1 loop KDGDGCITTEΔD1K11 SEQ ID NO: 72EF-hand1 loopDKGDGCITKEΔD3T10 SEQ ID NO: 73EF-hand1 loopDKGDGCITTEΔD3K11 SEQ ID NO: 74EF-hand1 loopKDGDGCITEΔD1T10K11 SEQ ID NO: 75EF-hand1 loopDKGDGCITEΔD3T10K11 SEQ ID NO: 76EF-hand2 loopADGNGTIDPEΔD1F10 SEQ ID NO: 77EF-hand2 loopADGNGTIDFEΔD1P11 SEQ ID NO: 78EF-hand2 loopDAGNGTIDPEΔD3F10 SEQ ID NO: 79EF-hand2 loopDAGNGTIDFEΔD3P11 SEQ ID NO: 80EF-hand2 loopADGNGTIDEΔD1F10P11 SEQ ID NO: 81EF-hand2 loopDAGNGTIDEΔD3F10P11 SEQ ID NO: 82EF-hand3 loopKDQNGFISAEΔD1A10 SEQ ID NO: 83EF-hand3 loopKDQNGFISAEΔD1A11 SEQ ID NO: 84EF-hand3 loopDKQNGFISAEΔD3A10 SEQ ID NO: 85EF-hand3 loopDKQNGFISAEΔD3A11 SEQ ID NO: 86EF-hand3 loopKDQNGFISEΔD1A10A11 SEQ ID NO: 87EF-hand3 loopDKQNGFISEΔD3A10A11 SEQ ID NO: 88EF-hand4 loopVDGDGQINEEΔD1Y10 SEQ ID NO: 89EF-hand4 loopVDGDGQINYEΔD1E11 SEQ ID NO: 90EF-hand4 loopDVGDGQINEEΔD3Y10 SEQ ID NO: 91EF-hand4 loopDVGDGQINYEΔD3E11 SEQ ID NO: 92EF-hand4 loopVDGDGQINEΔD1Y10E11 SEQ ID NO: 93EF-hand4 loopDVGDGQINEΔD3Y10E11
	summary
039909417	summary	BACKGROUND OF THE INVENTION A nuclear reactor pressure vessel installation is disclosed by the U.S. Keller Application Ser. No. 367,955, filed June 7, 1973, as comprising a pressurized-water reactor pressure vessel surrounded by the wall of a biological shield which forms a space between it and the vessel. Vertical steel beams, each formed in part by two vertical steel channels, are circumferentially interspaced at relatively large distances around the periphery of the reactor pressure vessel to support the latter, but while forming vertical passages of extensive cross-sectional area to which the pressurized-water coolant can escape upwardly with little resistance, in the event the pressure vessel ruptures. With this relatively large circumferential interspacing of the vertical beams, the wall of the pressure vessel remains substantially unsupported throughout each area between the interspaced beams. However, upwardly extending spaces are formed having the advantage that they may be used for the upward flow of air coolant between the pressure vessel wall and the concrete wall to protect the latter against excessive heating. SUMMARY OF THE INVENTION The object of the present invention is to provide an installation having for practical purposes the same possibility for upward flow of a coolant, such as air, between the vessel and the concrete wall, while at the same time providing for the radial support of the pressure vessel wall in a manner that is substantially circumferentially continuous so that the risk of such a pressure wall rupture is very greatly reduced. According to the invention, the heat insulation layer, which is, of course, made of pressure-resistant concrete, such as cast concrete blocks, surrounds the pressure vessel wall in the circumferentially continuous manner as before. Also, vertical steel beams are positioned between the heat insulation layer and the concrete wall formed by the biological shield. However, the difference is that the steel beams, which have webs and flanges characteristic of rolled steel structural shapes, are positioned circumferentially very close together with the flange edge of each beam engaging the flange edge of each adjacent beam so that a continuous steel wall circumferentially surrounds the heat insulation in contact therewith, and a corresponding steel wall engages the concrete wall with the webs of the beams functioning as vertically continuous struts. Preferably the beams are formed by conventional structural steel H or I beam shapes, although channel shapes may conceivably be used. With the first-mentioned shapes, the flanges which engage the heat insulation can be butted against each other to provide the heat insulation layer, and, therefore, the pressure vessel wall, with a circumferentially and vertically continuous steel wall. The usual pressure vessel is generally cylindrical with its heat insulating layer being correspondingly shaped, the contour of the concrete wall of the biological shield being correspondingly contoured. This means that the beam webs are inherently radially arranged so that their flanges which engage the concrete wall are slightly interspaced circumferentially. Due to the diameter of any reactor pressure vessel of what would be currently considered to be provided by a reactor of high power, the flange interspacing around the concrete wall is very slight. The vertical coolant channels formed between the beam webs can almost be considered to be circumferentially continuous, being interrupted only by the flanges which are relatively thin. When air or other coolant is passed upwardly between the beam flanges, a steel skin can be interposed between the flanges and the heat insulation layer, to prevent the leakage of the cooling air through the heat insulation layer to the pressure vessel wall, keeping in mind that the heat insulation layer is ordinarily formed by large concrete blocks which possibly provide leakage paths via their abutting edges.
058825525	abstract	A method is disclosed in which fuel scrap of UO.sub.2 alone or UO.sub.2 containing an oxide of plutonium, gadolinium or erbium is recycled into the manufacture of nuclear fuel pellets. The fuel scrap consisting of defective fuel pellets is comminuted through oxidation to fuel particles of U.sub.3 O.sub.8 alone or U.sub.3 O.sub.8 containing an oxide of plutonium, gadolinium or erbium, and a sintering aid containing an element selected from the group consisting of aluminum, magnesium, niobium, titanium, vanadium, chromium, lithium, silicon, tin and mixtures thereof is added in a quantity of about 0.02% to about 2% by weight to the sintering powder which consists of said recycled fuel particles and fresh fuel powder having a composition of UO.sub.2 alone or UO.sub.2 in a mixture of PuO.sub.2, Gd.sub.2 O.sub.3 or Er.sub.2 O.sub.3. The sintering powder is then mixed uniformly, in which the amount of the recycled fuel particles is in the range of about 10% to about 100% by weight. Green pellets are made by pressing the sintering powder and then sintered at about 1500.degree. C. to about 1800.degree. C. in a reducing atmosphere to produce new fuel pellets.
	description	This application is a continuation of U.S. application Ser. No. 11/298,590, filed Dec. 12, 2005 now U.S. Pat. No. 7,187,345, which claims priority from Japanese patent application JP 2005-221185, filed Jul. 29, 2005 and JP 2005-338009, filed Nov. 24, 2005, the contents of which are incorporated herein by reference. The present invention relates to an image forming method using a charged particle beam, and a charged particle beam apparatus. In particular, the present invention relates to an image forming method and a charged particle beam apparatus capable of suppressing the influence of charging. If an electron beam is applied to a sample, secondary electrons are generated. In scanning electron microscopes, an observed image on the surface of the sample is obtained using a phenomenon that the quantity of generation of secondary electrons changes depending upon the shape of the sample. In conventional scanning electron microscopes, scanning is conducted in the horizontal direction, i.e., in the raster direction in the screen every line (every horizontal line in the screen). The order of scanning lines is a descending order from the top to the bottom in the vertical direction in the screen. In the scan scheme according to the conventional technique, raster scanning is conducted successively from the top to the bottom in the vertical direction in the screen. In the vertical direction, therefore, inclination is often generated in the charging phenomenon generated by electron beam radiation. In other words, when a certain line is being scanned, charge remaining on a line already scanned immediately before affects the primary electron beam and the secondary electron beam in scanning, changes their trajectories, and distorts a finally obtained sample image. In JP-A-2005-142038, it is described to reduce the influence of charging by conducting interlaced scanning using the charged particle beam. According to the technique disclosed in JP-A-2005-142038, accumulation of charging can be mitigated to some degree by interlaced scanning. Since the time interval for forming neighboring scanning lines is not sufficient, however, there is a problem that the inclination of charging remains. An object of the present invention is to provide an image forming method and a charged particle beam apparatus suitable for suppressing the inclination of charging when scanning a two-dimensional area with a charged particle beam. According to a method, and apparatus, proposed by the present invention, a third scanning line located between a first scanning line and a second scanning line is scanned. After the first, second and third scanning lines have been scanned, a plurality of scanning lines are scanned between the first and third scanning lines and between the second and third scanning lines. According to such a configuration, the first, second and third scanning lines have intervals including a plurality of scanning lines. Therefore, it becomes possible to prevent residual charging on one scanning line from affecting other scanning lines. In addition, while scanning a plurality of scanning lines between the first and third scanning lines and between the second and third scanning lines, it is possible to mitigate the charging. Over the scanning area, therefore, it is possible to mitigate the influence of the absolute charging and suppress the inclination thereof. As an example of such a configuration, it is desirable to locate a fourth scanning line to be scanned after the scanning of the first, second and third scanning lines is located on a center line between the first and third scanning lines (positions at equal distances from the first and third scanning lines) or on a center line between the second and third scanning lines. According to such a configuration, the fourth scanning line is located in a position in the scanning area that is least susceptible to the influence of the charging on the first, second and third scanning lines. Therefore, it becomes possible to effectively suppress the inclination of the charging. Other configurations and specific examples of the present invention will be described in detail with reference to embodiments. According to the present invention, it becomes possible to provide a method, and apparatus, for forming an image free from brightness inclination. Other objects, features and advantages of the invention will become apparent from the following description of the embodiments of the invention taken in conjunction with the accompanying drawings. In embodiments described hereafter, the order of conducting raster scanning in the vertical direction in the screen is determined so as to always conducting scanning between two arbitrary lines scanned previously in order to prevent the sample image from being distorted by influence of local surface charging. By doing so, it is possible to obtain a favorable image from a sample made of materials of two kinds described below. In other words, in the case of a material that leaves charging on already scanned lines for a long time, influences of previous scans are always balanced on a line that is being scanned, in the vertical direction and mitigated. This is because influences of charging on two previously scanned lines are canceled each other on a line located at equal distances from the lines. In the case of the other material, i.e., a material that causes charging on an already scanned line to disappear after a definite time, always taking a middle line between two previously scanned lines means always taking a statistical distant place that is least susceptible to any of a plurality of previously scanned in the past, at a definite time. Finally, it becomes possible to keep the distortion of the sample image caused by the influence of surface charging at a minimum. Hereafter, a first embodiment of the present invention will be described with reference to the drawings. A first embodiment of the present invention is shown in FIG. 1. The present embodiment will now be described by taking a scanning electron microscope which conducts scanning with an electron beam and forms a two-dimensional image of the sample as an example. However, the present embodiment is not restricted to this. If the influence of charging cannot be neglected, it is also possible to apply the present embodiment to an FIB (Focused Ion Beam) apparatus, which conducts scanning with an ion beam and forms an SIM (Scanning Ion Microscope) image. As shown in FIG. 1, the present embodiment includes an electron beam source 1, a first converging lens 3 and a second converging lens 4 for focusing a primary electron beam 2 emitted from the electron beam source 1, deflectors 5 for deflecting the primary electron beam 2 to scan a surface of a sample 7 with the primary electron beam 2, an object lens 6 for focusing the primary electron beam 2 onto a surface of the sample 7, a secondary electron detector 12 for detecting secondary electrons 16 generated after the primary electron beam 2 strikes against the surface of the sample 7, a first converging lens power supply 8 and a second converging lens power supply 9 respectively for driving the first converging lens 3 and the second converging lens 4, a deflection signal generator 11 for generating deflection signals so as to scan the surface of the sample 7 with the primary electron beam 2 in accordance with a predetermined method, deflector drivers 10 for driving the deflectors 5 in response to the deflection signal, an amplifier 13 for amplifying a secondary electron signal detected by the secondary electron detector 12, an image construction apparatus for generating an image on the basis of the amplified secondary electron signal, an object lens power supply 14 for driving the object lens 6 so as to focus the primary electron beam 2 in a predetermined position, and a controller 15 for controlling the components heretofore described. If a line 17a on the sample 7 is first scanned with the primary electron beam 2, then a line 17b is scanned. Subsequently, a line 17c that is located at equal distances from the already scanned lines 17a and 17c is scanned. Detailed operation of the deflection signal generator 11 and the image construction apparatus 18 will now be described with reference to FIG. 2. In the deflection signal generator 11, an address generation circuit 22 outputs an address indicating a position on the sample 7 to which the electron beam should be applied, in accordance with a clock output from a write clock output circuit 21. On the basis of the address, D/A converters 23 generate analog signals respectively corresponding to quantities by which the primary electron beam 2 should be deflected respectively in the horizontal direction and the vertical direction. In accordance with the analog signals, the deflector drivers 10 drive the deflectors 5. The image construction apparatus 18 operates as described below. In other words, a secondary electron signal detected by the secondary electron detector 12 is amplified by the amplifier 13, and then converted to a digital signal by an A/D converter 24. This digital signal is stored in a memory group included in an illustrated image memory 26 via an input switch 25. The selected memory group is associated in one to one correspondence with a line indicated by an address that is generated by the address generation circuit 22. The deflection position of the primary electron beam generated by the address generation circuit 22 is controlled in accordance with a deflection pattern A shown in FIG. 3. Image data of lines sent from the image memory are not in the descending order in the vertical direction (perpendicular to the lines) in the observation area on the sample. The input switch 25 rearranges these image data in accordance with the deflection pattern A so as to arrange them in the descending order in the vertical direction in the image memory. If images corresponding to a predetermined area on the sample 7 are obtained by repeating such a procedure, the image data stored in the image memory 26 is displayed in accordance with a procedure hereafter described. That is, a read address generation circuit 28 outputs an address, which indicates a position on a display device 33 on which drawing should be conducted, in accordance with a clock output from a read clock output circuit 27. On the basis of the address, D/A converters 29 generate analog signals corresponding to quantities by which the drawing electron beam generated in the display device 33 should be deflected respectively in the horizontal direction and the vertical direction. Deflection amplifiers 30 drives drive the deflectors within the display device 33 in accordance with the analog signals. At this time, the image construction apparatus 18 operates as hereafter described. That is, in a state in which image data are already stored in the image memory 26, image data corresponding to one line is read out from a memory group in the image memory 26 indicated by an output switch 31 as a digital signal. The memory group selected here is associated in one-to-one correspondence with the line indicated by the address generated by the address generation circuit 28. A D/A converter 32 converts the digital signal read out to an analog signal, and supplies the analog signal to the display device 33. In the display device 33, luminance of the drawing electron beam generated from a cathode is changed in accordance with the analog signal. In addition, the drawing electron beam is deflected by the deflectors included in the display device 33 described earlier. As a result, an image is displayed. The position of drawing on the display device 33 which is generated by the read address generation circuit 28 is controlled in accordance with a deflection pattern B shown in FIG. 4. Therefore, image data of lines output from the image memory have a descending order in the vertical direction (perpendicular to the lines) in the observation area on the sample. The output switch 31 sends these image data in order in accordance with the same deflection pattern B. A scanning electron microscope image of the sample is displayed via these processes. Apart from FIG. 2, the image data stored in the image memory 26 are sent to the controller 15 and subject to appropriate processing to achieve the predetermined object. The deflection pattern A will now be described with reference to FIG. 3. In the scanning electron microscope according to the present invention, scanning is conducted in the horizontal X direction at definite periods in accordance with a sawtooth waveform. This is called raster scan. On the other hand, in the vertical Y direction, the scanning position is controlled in conformity with the periods of the raster scan. In the case of the deflection pattern A, a line located in a scanning line position “1” is scanned in a period α). A line located in a scanning line position “17” is scanned in a period β), and a line located in a scanning line position “9” is scanned in a period y). A line located in a scanning line position “13” is scanned in a period d), and a line located in a scanning line position “5” is scanned in a period ε). The deflection pattern B will now be described with reference to FIG. 4. In accordance with the deflection pattern B, the deflection of the primary electron beam is conducted in the same way as the conventional scanning electron microscope. Each time the period advances as represented by a)→b)→c)→d)→e), scanning is conducted on a line located in a position obtained by causing a stepwise movement with a predetermined interval corresponding to one line or two lines. FIG. 5 shows an example of a trajectory obtained when the sample 7 is scanned with the primary electron line 2 in accordance with the deflection pattern A. For example, in an arbitrary area formed by seventeen lines as shown in FIG. 5, an Nth scan, an (N+1)-st scan, an (N+2)-nd scan, an (N+3)-rd scan and an (N+4)-th scan are conducted on a line 1, a line 17, a line 9, a line 13 and a line 5, respectively. In other words, the (N+3)-rd scan is conducted on a center line in an area (having a first scanning line interval) prescribed by lines respectively associated with the (N+1)-st scan and the (N+2)-nd scan, and the (N+4)th scan is conducted on a center line in an area (having a first scanning line interval) prescribed by lines respectively associated with the Nth scan and the (N+2)-nd scan. In intervals (having a second scanning line interval) between two of the lines “1,” “5,” “9,” “13” and “17,” a plurality of scanning lines still remain to be scanned. Therefore, it becomes possible to prevent the charging generated on each scanning line from affecting other scanning lines. Subsequently, any of lines “3,” “7,” “11” and “15” is scanned. This scan on the lines “3,” “7,” “11” and “15” corresponds to the following operation: after the scan on center lines between scanning lines having equal scanning line intervals (scans on the lines “5” and “13”) has been finished, scan is newly conducted on scan lines having narrowed intervals from the already scanned scan lines (the lines “1,” “5,” “9,” “13” and “17”). By thus repeating a process of subsequently conducing scanning on a scanning line located on a center line between already scanned lines, it becomes possible to suppress the inclination of charging. This effect becomes more remarkable when the number of scanning lines is large. When scanning M scanning lines, a line 1 is first scanned and a line M is secondly scanned, and then a line m located on a center line between the line 1 and the line M is thirdly scanned. (If M is even, a scanning line that is the closest to the center line between the line 1 and the line M is selected.) Subsequently, the line 1 and the line m, or the line m and the line M are regarded as the original line 1 and line M, and a center line between them is scanned. By repeating such processing and conducting processing of gradually narrowing the interval between the line 1 and the line M, it is possible to sustain the effect of preventing the charging phenomenon of each scanning line from affecting other scanning lines for a long time. Owing to the configuration heretofore described, it is possible to implement a scanning electron microscope capable of suppressing the inclination of the charging phenomenon caused in the direction perpendicular to the raster scan by scanning on the sample with the electron beam. In the case of the present example, a new scanning line is set in a position that is at the greatest distance from the already scanned position, and an interval between consecutive scanning lines is made equal to an interval corresponding to a plurality of scanning lines. As a result, it becomes possible to suppress the rise of the charging value over the entire scanning area, and it becomes possible to effectively prevent the inclination of the charging phenomenon. When scanning one frame or one area, finally a new scanning line is set in a position that is in close vicinity to an already scanned position. At that time, however, the charging state on the already scanned scanning line is mitigated to some degree. As a whole, therefore, it becomes possible to suppress the charging state. An example of an effect obtained using the scanning electron microscope according to the present embodiment is shown in FIG. 6. If a hole formed by a specific material and called contact hole is observed using conventional TV scanning, an ellipse that is longer in the vertical direction is obtained as represented by a dot-dash line. By using the scanning method according to the present invention, however, it becomes possible to observe the contact hole in its original shape that is close to the real circle and shown by a solid line. A profile of the same contact hole image along a section A-B is shown in FIG. 7. In the image obtained using the conventional TV scanning and represented by the dot-dash line in FIG. 6, the profile is shown to be higher on a B side located on the bottom side in the vertical direction on the screen and scanned last as compared with an A side located on the top side and scanned first. This indicates that the image is displayed brightly on the B side as compared with the A side. In an image obtained by the scan method according to the present invention and represented by a solid line in FIG. 6, however, there is no inclination, i.e., there is no brightness difference on the profile between the A side and the B side. A deflection pattern C used when linking predetermined areas continuously to form one screen will now be described with reference to FIG. 8. FIG. 8 shows an example obtained when two areas are linked to form one screen. In the present example, “a” and “e” lines located respectively in areas 1 and 2 are first scanned in order. In the present example, a1 is scanned in a period a1, and a2 is scanned in a period b1. Then e1 is scanned in a period c1, and e2 is scanned in a period d1. Subsequently, two “g” lines are scanned extending over areas. And two “c” lines located between the already scanned “a” and “e” lines are scanned. And remaining scanning lines are scanned, and all scanning lines are scanned. It becomes possible to mitigate the influence of the charging by setting a position that is located at the greatest distance from a plurality of scanning lines as the next scanning position on the basis of the previously scanned scanning position. Finally, two areas taken in are linked to form one screen. FIG. 9 shows an example of a trajectory obtained by scanning the sample 7 with the primary electron beam 2 according to the above-described deflection pattern C. In the example shown in FIG. 9 as well, it is desirable to conduct the processing of repeating the process in which a center line between already scanned lines is scanned as the next scanning line as described with reference to the example shown in FIG. 5. In the present example, the example in which a scanning area is divided into two parts and processed has been described. However, this is not restrictive. For example, the area may be divided into four parts, eight parts, sixteen parts, thirty-two parts, or sixty-four parts. If the number of parts obtained by the division is too large, the effect of the present embodiment is decreased. Therefore, it is desirable to limit the number of parts to approximately sixty-four. The reason will now be described. If the number of scanning lines is too large, the next scanning line is scanned in the adjacent position in the state in which the influence of charging generated by the previous scanning line remains, resulting in inclination of charging. If scanning is conducted so as to produce a common scanning sequence every area produced by the division, it is possible to prevent the charging state from inclining every area. In addition, it is possible to provide the controller with a function of changing over the number of parts obtained by the division and change over the scanning pattern according to the changeover in the number of parts. FIG. 10 shows an example obtained when the present invention is applied to the interlaced scanning. In the interlaced scanning, lines are selected alternately and scanned, and remaining lines are scanned at the next step. By the way, in the conventional TV scanning, the interlaced scanning is basically adopted. FIG. 10 shows the case where two areas construct a screen. In the present example, first, all lines of a_even located first in areas 1 to 2 are scanned in order. In FIG. 10, a1_even is scanned in a period a1 and a2_even is scanned in a period b1. Then c1_even is scanned in a period c1 and c2_even is scanned in a period d1. Subsequently, extending over areas, c_even lines located between two already scanned a_even lines are scanned in the areas 1 to 2. In FIG. 10, c1_even is scanned in a period y1 and c2_even is scanned in a period δ1. Then d1_even is scanned in a period α2 and d2_even is scanned in a period β2. Subsequently, d_even lines located between the already scanned c_even lines and a_even lines in the next area, and b_even lines located between the a_even lines and c_even lines are scanned in the same way. To this point, scanning corresponding to one field “even” in the interlaced scanning is finished. Lines corresponding to “odd” located between lines alternately scanned in “even” are scanned one after another in periods α3 to δ4 in the order of a_odd→c_odd→d_odd→b_odd in the same way as “even.” The remaining one field corresponding to “odd” is taken in. Finally, one field in the “even” and one field in the “odd” are compounded to construct one screen. FIG. 11 shows an example of a trajectory obtained when the sample 7 is scanned with the primary electron line 2 in accordance with a deflection pattern D. For example, it is now assumed that one screen is formed of two areas as shown in FIG. 11. An Nth scan and an (N+1)-st scan are conducted respectively on a line a1_even and a line a2_even in the next area. Returning to the previous area, an (N+2)-nd scan is conducted on a line c1_even. An (N+3)-rd scan is conducted on a line c2_even in the next area again. Hereafter, scans are conducted on lines corresponding to “even” in the interlaced scanning until an (N+7)-th scan on a line b2_even. After the scans corresponding to “even” lines in the interlaced scanning have been finished, (N+8)-th to (N+15)-th scans are conducted on lines corresponding to “odd” in the same way. FIG. 12 shows an example in which only one line is exempted from the rule of the present embodiment and a scan is conducted on a screen end without taking a center line between two lines scanned earlier. Even if such scanning is conducted, there is no substantial change in the effect of the present invention. In other words, even if scans overlap at the screen end and partial inclination of charging occurs in the portion, the charging situation in a principal portion of the screen is not affected. Furthermore, even if two lines are added at the screen end instead of only one line as shown in FIG. 13, there is no change in the effect of the present invention. Furthermore, even if only one line is scanned not at the bottom end of the screen but at the top end as shown in FIG. 14 without taking a center line between two lines scanned earlier, there is no change in the effect of the present invention. An example in which pattern length measurement is conducted on the basis of an image formed using a scanning method of scanning a center line between scanning lines one after another as described above will now be described. FIG. 15 is a diagram showing an example of an image formed using the scanning method of the present example. On this image, a line pattern bent in a part thereof by 90 degrees is displayed. When measuring the line width of such a line pattern, the scanning line direction of the raster scan and the sample direction are set in the conventional technique so as to make the pattern edge perpendicular to the scanning line direction of the raster scan. Because a length value measured in the scanning line direction of the raster scan becomes different from that measured in other directions as illustrated in FIG. 16 although the line width is the same. Since in this way the length value measured in the scanning line direction becomes different from that measured in other directions, there is a problem that the length value measured in a direction other than the scanning line direction cannot be ensured. As cause of difference in measured length value or magnification between the scanning line direction (such as the X direction) and another direction (such as the Y direction), influence of charging is conceivable. If one scanning line is scanned and then scanning is conducted in an adjacent place, scanning using the electron beam is conducted at an interval different from the intended scanning line interval under the influence of charging in the previously scanned place. Therefore, it is considered that the magnification in the X direction and that in the Y direction do not have the relation of 1:1. Such a problem is solved in the present example as follows. When scanning a two-dimensional area on the sample by using a plurality of scanning lines, a third scanning line is scanned between a first scanning line and a second scanning line, and then a plurality of scanning lines are scanned between the first scanning line and the second scanning line and between the second scanning line and the third scanning line. In addition, the length measurement direction can be set in a direction different from a scanning line direction of an image formed on the basis of the scanning. Specifically, a length measurement range setting box 40 is provided as shown in FIG. 15 so as to be capable of setting the length measurement direction in a direction (which is a direction perpendicular to the scanning line direction in the case of the present example) different from the scanning line direction. Owing to the scanning specific to the present example, it is possible to suppress the magnification error caused between the scanning line direction and another direction (especially, a direction perpendicular to the scanning line direction). According to the present example, therefore, it becomes possible to measure the length accurately irrespective of the direction. This effect is demonstrated especially when measuring the length as shown in, for example, FIG. 15. In the example shown in FIG. 15, two length measurement points 41 and 42 that are different in length measurement direction are present on one image. When conducting such length measurement, it is necessary in the conventional technique to change the scanning line direction every two length measurement points in order to ensure the length measurement precision. The present example has an effect that length measurement in a plurality of directions can be conducted at high precision on one screen. If the actual illustrated line pattern has the same line width, it is possible in the present example to square a line width L in the X direction with a line width Lrr in the Y direction with high precision irrespective of the scanning direction. In addition, conducting the above-described scanning also brings about an effect that the length can be measured with high precision even if the scanning line direction is rotated and the scanning line direction is set to an arbitrary direction. It also becomes possible to maintain high length measurement precision irrespective of the scanning direction by rotating the scanning direction (i.e., conducting raster rotation) as described in FIG. 16. By the way, the length measurement range setting box 40 can be displayed on the formed image, and positions of measurement reference positions 43 and 44 can be arbitrarily set. The measurement reference positions 43 and 44 can be set in arbitrary positions on the image by using, for example, a pointing device, which is not illustrated. The controller 15 is programmed so as to, for example, store the length measurement range setting box 40, count pixels between the measurement reference positions 43 and 44 in the length measurement range setting box 40, and measure the length between the measurement reference positions 43 and 44 on the basis of magnification set at that time. An example of further mitigating the influence of the charging by combining a faster scanning rate with the scanning method described with reference to the first embodiment will now be described. FIGS. 17A and 17B are diagrams showing deflection patterns (deflection patterns E and F represented by solid lines) used when scanning using the electron beam is conducted at a scanning rate that is twice with respect to the deflection patterns A and B described in the first embodiment. Observation and measurement become possible even for a sample affected by the charging more remarkably by combining the suppression of charging obtained using scanning faster than the ordinary scanning with the scanning method described with reference to the first embodiment. FIG. 22 is a diagram showing an example of a GUI (Graphical User Interface) for setting various scanning methods including the scanning method of the present example and the scanning rate. In a GUI screen shown in FIG. 22, a window for selecting an ordinary television scan or the scanning method described in the first embodiment (represented as “anti-charge” scan because it is a scanning method that is effective against charging) and a window for selecting a scanning rate (fast scanning, normal scanning, and slow scanning) are included. Here, the fast scanning refers to scanning conducted at the scanning rate as shown in FIGS. 17A and 17B (supposing that scanning conducted at the scanning rate as shown in FIGS. 3 and 4 is normal scanning). Scanning conducted at a scanning rate as shown in FIGS. 23A and 23B is slow scanning. If the TV scan is selected, inhibition processing is conducted in the present example to prevent the slow scan from being selected. If the anti-charge scan is selected, it is allowed to select the slow scan. Since the scanning method described in the first embodiment is not susceptible to the influence of charging, scanning can be conducted at a relatively slow rate as compared with the TV scan. Therefore, the slow scan is made selectable when the scanning method described in the first embodiment is selected, whereas the slow scan is not made selectable when the scanning method described in the first embodiment is not selected. When scanning a sample that is easily affected by the charging, this prevents a combination of the scanning method that stores charging on the sample (TV scan) with the slow scan that stores charging on the sample (a deflection pattern H) from being falsely selected. If the TV scan is selected and then the fast scan, the normal scan or the slow scan is selected, the deflection pattern F, the deflection pattern B or the deflection pattern H is selected in the present example, respectively. If the anti-charge scan is selected and then the fast scan, the normal scan or the slow scan is selected, then the deflection pattern E, the deflection pattern A or the deflection pattern G is selected, respectively. As heretofore described, the influence of charging on the sample differs depending upon the scanning method with the electron beam. By changing the setting range of selectable parameters concerning the electron beam according to the scanning method, therefore, it becomes possible to set arbitrary parameters without considering the influence of charging. In the present example, the setting parameters are the scanning method and the scanning rate. However, this is not restrictive. It is also possible to set the kind of the sample that differs in influence of charging as a part of the setting parameters. At this time, it is conceivable to conduct inhibition processing, such as preventing the slow scan from being selected or preventing the raster scan from being selected, when a sample kind that is easily affected by the charging is selected. Furthermore, the beam current and magnification can become a part of the setting parameters. In the present example, desired setting can be conducted using a pointing device which is not illustrated. The parameters set on the GUI screen shown in FIG. 22 are sent to the controller 15, and converted to control signals for the deflectors. In the pre-charging technique, the sample surface is charged previously by applying an electron beam, and scanning is conducted with an electron beam for forming an image under the charged state. An example in which the above-described scanning method is applied to the pre-charging technique will now be described. FIG. 18 is a schematic diagram showing the pre-charging technique (pre-dose). The pre-charging technique is a technique of charging the sample surface positively by electron beam irradiation in order to pull up electrons from, for example, the bottom of a contact hole of a semiconductor device. It becomes possible to pull up secondary electrons efficiently from the bottom of the contact hole by applying the electron beam for forming an image under the positive charging state. For that purpose, scanning with an electron beam for previously charging the sample surface is conducted before scanning with an electron beam for forming an image is executed. Such a pre-charging technique is described in JP-A-5-151927 (corresponding to U.S. Pat. No. 5,412,209) and JP-A-2000-200579 (corresponding to U.S. Pat. No. 6,635,873). In this example, it is proposed to use a scanning method of scanning a third scanning line between a first scanning line and a second scanning line, and then scanning a plurality of scanning lines between the first scanning line and the second scanning line and between the second scanning line and the third scanning line, as the scanning for the pre-charging. The pre-charging scanning aims at charging the sample surface. The prime object of the pre-charging scanning is to detect secondary electrons from the bottom of the stable contact hole with high efficiency by sustaining the charged state. If charging is conducted with inclination, therefore, a bad influence is exerted on the scanning for forming an image over a long time. In view of such circumstances, in the present example, the pre-charging scanning as described above is conducted and then the scanning for forming the image is conducted. By thus conducting the scanning, it becomes possible to form a stable charging state having no inclination. In the example described with reference to FIG. 18, magnification in the pre-charging scanning is made lower than that for forming the image. However, this is not restrictive. It is also possible to conduct the pre-charging scanning by scanning the sample surface with an electron beam having arrival energy with a secondary electron emission efficiency δ>1. FIG. 19 is a diagram showing a change of brightness in the Y scanning direction obtained when the pre-charging scanning is conducted using the ordinary TV scan and when the pre-charging scanning is conducted using the scanning method in the present example. A dot-dash line represents a change of image brightness obtained when the TV scan is conducted. In the ordinary scanning, the next scanning line is scanned in the vicinity of a scanning line, and this is repeated. As the position moves from the top of the image to the bottom, therefore, charging is gradually accumulated. Since the top of the image is thus different in charging state from the bottom, the top differs in brightness from the bottom. If scanning for measurement is conducted in such a state, a line profile representing a change of the detected electron quantity and pixel brightness becomes as represented by the dot-dash line in FIG. 19 under the influence of inclined charging formed at the time of pre-charging. On the other hand, if the pre-charging is conducted using the scanning method of the present example, the charging state is stable irrespective of the position in the Y direction. Therefore, it becomes possible to form a proper line profile that represents the shape of the sample surface. FIG. 20 shows a scanning method obtained by further improving the scanning method described in the first embodiment. Scanning in the X direction is conducted alternately in opposite directions. That is, the line 1 is first scanned from the left side in FIG. 20 to the right side. Subsequently, the line 17 is scanned from the right side in FIG. 20 to the left side. Even if the sample is a sample on which charging is inclined depending upon the scanning direction and the influence of charging is accumulated, it becomes possible to form a sample image having high horizontal uniformity irrespective of the influence of charging, by thus changing the scanning direction every scanning line. FIG. 21 is a diagram showing an example in which the scanning method of scanning the next scanning line located on a center line between already scanned scanning line trajectories described in the first embodiment is developed two-dimensionally. In the case of the present example, first, an electron beam (N) (pulse beam) is applied to coordinates (17, 1) on a corner of a two-dimensional irradiation area in a spot form. Subsequently, an electron beam (N+1) is applied to coordinates (1, 17), which is at the longest distance from the coordinates (17, 1) in the scanning subject area. Subsequently, electron beams (N+3 and N+2) are applied to coordinates (1, 1) and coordinates (17, 17), which are located between the coordinates (1, 17) and the coordinates (17, 1) and which are at the longest distance from the coordinates (1, 1) and coordinates (17, 17). Thereafter, an electron beam (N+4) is applied to the center (9, 9) among irradiation positions to which the electron beams have been applied. In addition, electron beams (N+5, N+6, N+7, and N+8) are applied to centers among irradiation positions to which the electron beams have been applied. In addition, thereafter, applying electron beams to centers among irradiation positions to which the electron beams have been applied is repeated. As a result, irradiation over the entire scanning area is completed. By the way, the above-described scanning sequence is nothing but an example. For example, after the electron beam (N+4) has been applied, the next irradiation point may be set to a center of each of sides prescribing the two-dimensional irradiation area, such as coordinates (9, 17) between the coordinates (1, 17) and the coordinates (17, 17). It is desirable to position the next irradiation point on a center between two previous irradiation points and set the next irradiation point in a position that is at the longest distance from a point of last irradiation and a point of last irradiation but one, or a position close to the position. After beam irradiation to center positions having equal intervals between irradiation positions on coordinates has been finished, preferably the next irradiation positions are set to center positions having narrower intervals between irradiation positions, and the intervals between irradiation positions are gradually narrowed. By repeating deflections that position the next irradiation positions on the centers among already irradiated irradiation positions, irradiation over all coordinates spreading two-dimensionally is completed. By the way, even if an electron beam is applied in a pulse form as heretofore described, an image of a two-dimensional area on the sample can be formed by synchronizing the signal supplied to the scanning deflector with the deflection signals of the display device in the same way as the ordinary scanning electron microscope. When moving the beam between irradiation points, it becomes possible to selectively apply the electron beam to a desired irradiation position by diverting the trajectory of the electron beam from the sample with, for example, a deflector for blanking so as to prevent the electron beam from being applied to the sample. It should be further understood by those skilled in the art that although the foregoing description has been made on embodiments of the invention, the invention is not limited thereto and various changes and modifications may be made without departing from the spirit of the invention and the scope of the appended claims.
043483518	abstract	A method for controlling dopant variation in neutron silicon is provided wherein the selection of undoped single crystal silicon for neutron transmutation doping is based upon certain criteria, for example, a maximum dopant difference which depends only on the desired uniformity of the neutron doped material and a maximum average dopant concentration which is a function of the homogeneity of both the undoped single crystal silicon and the neutron doped product. The results achievable from using the method for controlling dopant variation in the neutron doped silicon provides uniformity of the neutron doped product determinable by the correct choice of dopant difference and dopant factor, and that the doping precision for the radiated silicon does not depend on the doping factor.
053213270	summary	The invention relates to an electric generator employing a plasma ball as an electric power generating medium, and more particularly employing a plasma bell of highly heated gas turning at a high speed of rotation in a vortex chamber. BACKGROUND OF PRIOR ART The use of a fast moving mass of gas plasma for the purpose of generating electric power is known from magneto hydrodynamic technology. In the known technology of hydrodynamics a gas plasma of high-temperature ionized gas is driven at high velocity through a magnetic field so that an electromotive force is generated by the moving gas plasma and tapped off at electrodes in the plasma. The technology of magneto hydrodynamics has never been developed to the point wherein it has become commerically successful, due to the fact that the gas plasma exiting the magnetic field still contains a considerable amount of thermal energy that is not converted into electric power. The instant invention overcomes this drawback by means of a different approach to converting the hot gas plasma to electric energy, which utilizes a principle of a vortex formed in the gas plasma, and more particularly a principle of so-called imploding plasma vortex dynamics in the following disclosure termed "Imploding Plasma Dynamics", wherein the plasma is in continuous contact with the electrodes until they have released the major part of its kinetic energey, SUMMARY OF THE INVENTION A sustained implosion of highly heated, high velocity rotating imploding vortices of a gas plasma containing fuel and air mixture is created within an ionizing chamber prior to combustion of the imploding vortices. The system is arranged to maximize formation of laminar flow so as to stratify all molecular and atomic particles by particle mass. The laminar flow patterns operate to trap the heavier gas masses in very hot pressure areas so that they release the kinetic energy of their mass in the form of electric energy before they escape from the vortices followed by a return of lighter gases to a vacuum formed in a central core of the vortices in a continuously repeated cycle. The combustion in the plasma produces great quantities of free electrons that associate with and exchange energy with the highly heated stratified gas particles so as to produce an electrical potential due to the stratification of heavier masses and lighter masses of molecular and electron gases containing the large quantities of electrons and ions. Cooperating vortex and ionizing fuel chambers are arranged in a way so as to use these chambers as electrodes for supplying an electric current by the principle of imploding plasma dynamics. The apparatus for producing electrical energy according to the invention operates by combusting fuel in sustained rotating imploding vortices. It was discovered by the applicant that when such a system was properly understood and utilized, it provided a novel method of liberating electrical energy from different forms of gaseous liquid, powdery and solid fuels. this invention further includes a technology wherein the fuel is super preheated so as to make it chemically and molecularly very active and to enclose this preheated fuel into an electrically insulated ionizing chamber, containing large numbers of free electrons. Actual prototype tests have indicated that these electrons appear to attach themselves to the fuel molecules, causing the fuel molecules to become activated and to behave as a plasma within the vortex chamber. The plasma thus activated greatly increases the combustion temperature which further enhances formation of the plasma. Diesel oil that normally burns at 1200.degree. F. in a prototype system has shown a combustion temperature in excess of 2400.degree..TM. F. The flow patterns within this system operate to create the sustained implosion within the vortex chamber. The imploding vortex is a stratified system wherein the heavier particles of the gas masses become progressively stratified with the outer perimeter of the vortex and the lighter particles of the gas masses become progressively stratified around a central core due to the gravity gradient formed in the vortices. A greater pressure is formed along the outer perimeter and a lighter pressure or vacuum is formed along the central axis. It can also be demonstrated that the center of a high velocity combustion vortex is cool when compared with the temperature of its outer periphery. The disclosed invention utilizes all of the important characteristics of the imploding vortex so as to increase the energy conversion efficiency and to greatly reduce the pollutants commonly associated with combustion of hydrocarbon and other fuels. The invention as disclosed herein is believed to be a novel way of generating electricity in an efficient and nonpolluting manner. The disclosed invention utilizes the principle of imploding plasma dynamics such that in one embodiment, two counter rotating, imploding plasma vortices facing each other produce a magnetic field and release free, fast-moving electrons that produce a polarized electron gas that is in electrical contact with two insulated halves of the outer walls of the combustion chamber. The two halves are electrically insulated so as to form plus (+) and minus (-) electrodes giving the electrons conducting path so that they can be utilized for generating electrical energy. It is known that when too many free electrons exist within a system, the system will increase in temperature, and that the reverse is also true--i.e., if free electrons are drained from the system, it will reduce its temperature. In operation, the plasma ball will produce prodigious quantities of free, fast-moving electrons in a controlled and confined space, producing intensive heat that may exceed safe limits of its construction materials. Accordingly, cooling of the plasma ball is attained by draining surplus electrons from the system by always having a work load on the system. In accordance with the invention there is provided an electric generator using imploding plasma dynamics for generating electric energy from fuel energy, which includes a substantially cylindrical vortex chamber bounded by a cylindrical chamber wall having an axis, an inward curved fuel inlet end wall, and an opposite inward curved exhaust end wall; a shroud surrounding the vortex chamber forming an air space between the chamber wall and the shroud; at least one air inlet entering the air space at an angle tangential to the air space; air compressor means fluidly communicating with the air inlet for injecting air into the air space; fuel-air mixture injection means disposed in the fuel inlet end wall; a mixing chamber in the fuel-air mixture injection means for mixing fuel with the air fluidly communicating with the air space; a plasma expansion cone or other vortex forming means having an inlet fluidly communicating with the mixing chamber for receiving fuel-air mixture from the mixing chamber; ignition means in the plasma expansion cone for igniting the fuel-air mixture, and forming at least one imploding plasma vortex in the vortex chamber; and electric energy take-off means connected with the vortex chamber for taking off electric energy generated by the imploding plasma vortex. In accordance with a further feature, the electric generator may include magnetic field forming means for forming a radially extending magnetic field in the vortex chamber, the radially extending magnetic field cooperating with the imploding plasma vortex for generating an electromotive force in the vortex chamber connected with the electric energy take-off means, at least one permanent magnet in the magnetic field forming means, or at least one electromagnet in the magnetic field forming means. The electric generator may further include an outer cylindrical magnet and an inner conical magnet in the magnetic field forming means, the inner and outer magnets coaxially disposed with the axis of the vortex chamber, en exhaust tube fluidly communicating with the vortex chamber for releasing exhaust gas from the vortex chamber, and an exhaust gas inlet in the exhaust gas tube, the exhaust gas inlet disposed in the axis of the vortex chamber. The exhaust tube is advantageously disposed coaxially with the axis of the vortex chamber. According to another feature, the electric generator includes a heat protective also advantageously electrically conductive lining in the vortex chamber. According to still another feature, the electric generator includes a fuel line in the fuel-air mixture injection means connected to a source of liquid fuel, or to a source of gaseous fuel, and further liquid fuel vaporizing means for vaporizing the liquid fuel, connected to the fuel line. There may additionally be included a mixing chamber in the fuel-air mixture injection means, and a fuel injector connected to the fuel line for injecting fuel into the mixing chamber, and an ignitor in the ignition means, and a spark generator connected to the ignitor for igniting the fuel-air mixture. The electric generator according to the invention may advantageously include a plurality of exhaust reentry vanes in the plasma expansion cone and/or the premixing chamber for reentry of exhaust gas from the vortex chamber into the plasma expansion cone. The exhaust tube can be a metallic tube, and an electric insulator which insulatingly connects the exhaust tube with the vortex chamber. The electric generator according to the invention includes a first electric terminal in the electric energy take-off means, attached to the exhaust tube, a second electric terminal in the electric energy take-off means connected to the vortex chamber wall, and an electric voltage converter connected to the first and second terminal for converting the voltage of the electric energy to user-adjusted electric voltages. Another embodiment of the electric generator using imploding plasma dynamics for generating electric energy from fuel energy, includes: (a) two facing hemispheric vortex chambers having a common axis; PA1 (b) an insulator separating the vortex chambers, disposed in a plane perpendicular to the common axis; PA1 (c) two facing hemispheric shrouds each enclosing a respective one of the hemispheric vortex chambers, and forming respective air spaces with the vortex chambers; PA1 (d) two oppositely oriented air inlets for injecting air in opposite directions into the air spaces; PA1 (e) air compressor means fluidly communicating with the air inlets for injecting air into the air inlets; PA1 (f) respective fuel-air mixture injection means in the hemispheric vortex chambers, each fuel-air mixture injection means including a mixing chamber in fluid communication with a respective air space, a plasma expansion cone or other vortex-forming means fluidly communicating with a respective mixing chamber, ignition means in the plasma expansion cones for igniting the fuel-air mixture, and forming oppositely rotating imploding plasma vortices in the vortex chambers; and PA1 (g) electric energy take-off means for taking off electric energy generated by the oppositely rotating imploding plasma vortices. The electric generator according to the invention includes fuel preheating means having a preheated fuel outlet in fluid communication with the fuel line, and a fuel inlet for receiving liquid and/or gaseous fuel. The fuel preheating means may include the heat exchanger, a heating element, an electric power source connected to the heating element for electrically heating the heating element, and a fuel channel in the heating element for circulating fuel to be heated in the channel, the channel having a heated fuel outlet in fluid communication with the preheated fuel outlet, and wherein further the heating element is a coiled tube. The fuel-preheating means may include an electrolyzing electrode in the heat exchanger for electrolyzing the heated fuel, and an electrolyzing power source connected to the electrolyzing electrode for electrolyzing the heated fuel. Further objects and advantages of this invention will be apparent from the following detailed description of a presently preferred embodiment which is illustrated schematically in the accompanying drawings.
043292488	description	Six examples of the operation of the process according to the present invention are given below, together with certain modifications thereof. These examples relate to the immobilization of typical "high-Al" and "high-Fe" sludges possessing compositions as given in Table 3, Columns 1 and 2. Sludges possessing intermediate compositions, e.g. Table 3, Column 3 can be immobilized by treatments appropriately intermediate in nature between those described for Examples 1 and 2. EXAMPLE 1 (a) A "high-alumina" sludge characterized by a mixture of fission products and actinide elements with excess oxides of Al, Fe, Mn, Ni, U and Na, possessing the composition given in Table 3, Column 1, is mixed with about 30 percent of TiO.sub.2, ZrO.sub.2, CaO and SiO.sub.2, in proportions chosen so that when the mixture is heated, the added oxides combine with the sludge components to form a mineral assemblage consisting principally of hercyniterich spinel+perovskite+zirconolite+nepheline. The heat treatment is carried out under controlled redox conditions such that most of the iron and nearly all manganese and nickel is maintained in the divalent state. The mixture is heated at a temperature of 1200.degree. C. for several hours and simultaneously subjected to a confining pressure using the conventional technique known as hotpressing. Alternatively, the mixture may be formed and sintered at 1200.degree. C. under the appropriate redox conditions without the application of pressure. The resulting product is found to be a fine grained, mechanically strong rock composed of the above minerals in which the HLW fission products and actinides are effectively immobilized. Actual compositions of the minerals in a rock produced in this manner are given in Table 4. TABLE 4 ______________________________________ Compositions of coexisting mineral phases in high-alumina sludge (Table 3, Column 1) treated as described in Example 1(a). Nepheline Perovskite Zirconolite Hercynite ______________________________________ SiO.sub.2 41.5 -- -- -- TiO.sub.2 0.2 53.4 29.5 5.8 ZrO.sub.2 -- 0.7 37.8 0.3 UO.sub.2 -- 0.2 13.9 -- Al.sub.2 O.sub.3 35.9 2.4 1.1 48.2 Fe.sub.2 O.sub.3 -- -- -- -- FeO 0.8 2.7 4.1 37.4 MnO 0.2 1.7 0.9 7.2 NiO -- -- -- 0.4 CaO -- 39.6 12.3 -- Na.sub.2 O 21.5 0.3 0.4 -- Sum 100.1 101.0 100.0 99.4 ______________________________________ (b) In a modification of Example 1(a) above, the sludge is mixed with about 20-30 percent of the same oxides in proportions chosen to form a hercynite-rich spinel+zirconolite+nepheline mineral assemblage, and the mixture treated as above. A product physically similar to that of Example 1(a) is obtained with the fission products and actinides immobilized in the zirconolite phase. (c) A "high-alumina" sludge as described in Example 1(a), is pretreated by washing to reduce the sodium content, mixed with about 20-30 percent of TiO.sub.2, ZrO.sub.2 and CaO in proportions chosen to form a hercynite-rich spinel+perovskite+zirconolite mineral assemblage and the mixture treated as above. A product physically similar to that of Example 1(a) is obtained. (d) In a modification of Example 1(c) above, the sludge is mixed with about 20-30 percent of the same oxides in proportions chosen to form a hercynite-rich spinel+zirconolite mineral assemblage and the mixture treated as above. A product physically similar to that of Example 1(c) is obtained. EXAMPLE 2(a) A "high-iron" sludge, characterized by a mixture of fission products and actinide elements with excess oxides of Al, Fe, Mn, Ni, U and Na, possessing the composition given in Table 3, Column 2 is mixed with about 35 percent of TiO.sub.2, ZrO.sub.2, Al.sub.2 O.sub.3, CaO and SiO.sub.2 in proportions chosen so that when the mixture is heated, the added oxides combine with the sludge components to form a mineral assemblage consisting principally of ferrite spinel (Mn, Ni, Fe).sup.II Fe.sub.2.sup.III O.sub.4 +perovskite+zirconolite+nepheline. The heat treatment is carried out under controlled redox conditions such that most of the iron is in the trivalent state whilst most of the nickel and manganese are divalent. The mixture is heated at a temperature of 1200.degree. C. for several hours and simultaneously subjected to a confining pressure using the conventional technique known as hot-pressing. Alternatively, the mixture may be formed and sintered at 1200.degree. C. under the appropriate redox conditions without the application of pressure. The resulting product is found to be a fine grained, mechanically strong rock composed of the above minerals in which the HLW fission products and actinides are effectively immobilized. Actual compositions of the minerals in a rock produced in this manner are given in Table 5. TABLE 5 ______________________________________ Compositions of coexisting mineral phases in high-iron sludge (Table 3, Column 2) treated as described in Example 2(a). Nepheline Perovskite Zirconolite Ferrite Spinel ______________________________________ SiO.sub.2 40.6 -- -- -- TiO.sub.2 0.5 56.3 35.1 7.9 ZrO.sub.2 -- 0.6 25.2 -- UO.sub.2 -- 0.2 15.5 -- Al.sub.2 O.sub.3 34.4 0.1 0.4 8.1 Fe.sub.2 O.sub.3 5.0 3.9 7.8 43.5 FeO -- -- -- 20.7 MnO -- 1.0 1.8 9.0 NiO -- 0.2 -- 9.7 CaO -- 37.3 14.6 -- Na.sub.2 O 20.1 0.3 0.2 -- Sum 100.6 100.0 100.6 99.4 ______________________________________ (b) In a modification of Example 2(a) above, the sludge is mixed with about 20-35 percent of the same oxides in proportions chosen to form a ferrite spinel+zirconolite+nepheline mineral assemblage, and the mixture treated as above. A product physically similar to that of Example 2(a) is obtained with the fission products and actinides immobilized in the zirconolite phase. (c) A "high-iron" sludge as described in Example 2(a) is pretreated by washing to reduce the sodium content, mixed with about 20-35 percent of TiO.sub.2, ZrO.sub.2 and CaO in proportions chosen to form a ferrite spinel+perovskite+zirconolite mineral assemblage, and the mixture treated as above. A product physically similar to that of Example 2(a) is obtained. (d) In a modification of Example 2(c) above, the sludge is mixed with about 20-35 percent of the same oxides in proportions chosen to form a ferrite spinel+zirconolite mineral assemblage and the mixture treated as above. A product physically similar to that of Example 2(c) is obtained. EXAMPLE 3 This example is similar to Example 1(a) except that (i) about 40 percent of mixed oxides (TiO.sub.2 +ZrO.sub.2 +CaO+SiO.sub.2) are added to the sludge and (ii) a larger relative proportion of TiO.sub.2 is added than in Example 1(a). Under these conditions, the synthetic rock is found to contain a pseudobrookite-type solid solution (Al.sub.2 TiO.sub.5 --FeTi.sub.2 O.sub.5) in addition to the minerals mentioned in Example 1(a). In compositions richer in alumina than that given in Table 3, Column 1, a separate Al.sub.2 O.sub.3 phase (corundum) may also occur. EXAMPLE 4 The same procedure is followed as in Example 3, except that the added oxides contain some BaO. The mineral assemblage produced is similar to that in Example 3 except that a hollandite-type solid solution (BaAl.sub.2 Ti.sub.6 O.sub.16 --Ba(Fe, Ni, Mn, Ti).sub.2 Ti.sub.6 O.sub.16) is also produced in the synthetic rock. EXAMPLE 5 This example is similar to Example 2(a) except that (i) about 40 percent of mixed oxides (TiO.sub.2 +ZrO.sub.2 +CaO+SiO.sub.2 +Al.sub.2 O.sub.3) are added to the sludge and (ii) a larger relative proportion of TiO.sub.2 is added than in Example 2(a). Under these conditions, the synthetic rock is found to contain ilmenite (FeTiO.sub.3).+-.pseudo-brookite solid solution (FeTi.sub.2 O.sub.5 --Al.sub.2 TiO.sub.5) in addition to the minerals mentioned in Example 2(a). EXAMPLE 6 This example is similar to Example 5, except that the added oxides contain some BaO. The mineral assemblage produced is similar to that in Example 5 except that a complex davidite-type mineral Ba(Al, Fe.sup.III).sub.2 --Fe.sub.8.sup.II Ti.sub.13 O.sub.38 is also produced in the synthetic rock. Under some conditions, a hollandite-type phase Ba(Al,Fe.sup.III,Ni, Mn,--Fe.sup.II, Ti).sub.2 Ti.sub.6 O.sub.16 may also be produced. The above examples lead to the production of strong, stable synthetic rocks in which fission products and actinide elements are immobilized in a mineral assemblage as was described in the prior patent specification. That specification, described the great stability of titanate-based synthetic rocks to leaching and alteration in diverse geological and geochemical environments. The modified synthetic rock compositions described herein, characterized by much higher abundances of Al, Fe, Mn, Ni, U and Na than were considered in the prior specification share the preceding characteristics. The method of immobilizing HLW sludges described herein is greatly superior to the conventional technology of immobilizing the sludges by dissolving them in borosilicate glasses. Firstly, as shown in the prior patent specification, titanate-based synthetic rocks are enormously more stable toward leaching and decomposition than borosilicate glasses. Secondly, in most US defence HLW sludges, the proportion of fission products and actinide elements to "introduced" Al, Fe, Mn, Ni and Na oxides is very small, mostly between 0.5 and 5 percent. Thus, in most cases, it is only necessary to introduce from 20 to 40 percent of additional inert oxides (e.g. TiO.sub.2 +ZrO.sub.2 +CaO+SiO.sub.2) in order to form the desired mineral assemblage. Of course, it would be possible to introduce more than 40 percent of additional inert oxide components if found especially desirable for specific purposes. However, in most cases, this would not be necessary. Accordingly, it is possible to produce synthetic rocks containing 60-80 percent of sludge in the form of stable minerals. In contrast, it is not possible to incorporate readily more than 30 percent of sludge in borosilicate glasses. Moreover, because of the much higher density of synthetic rock (.about.4.5 g/cm.sup.3) compared to borosilicate glass (.about.3.0 g/cm.sup.3), a correspondingly higher weight of sludge can be incorporated in a given volume of rock as compared to glass. This results in considerable economic advantages when HLW sludges are incorporated in synthetic titanate rock. It will be appreciated by persons skilled in the art that many modifications and variations may be made to the specific embodiments described herein without departing from the spirit and scope of the present invention as broadly described herein.
	summary
062122525	description	DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the invention will be described below. (Embodiment 1) An X-ray mask of an embodiment 1 of the invention will be described below with reference to FIG. 1. Referring to FIG. 1, the X-ray mask of the embodiment 1 of the invention includes a support ring 1, a substrate 2, a membrane 3 and an X-ray absorber 4. Membrane 3 is formed on substrate 2. X-ray absorber 4 is formed on membrane 3. Support ring 1 is arranged under substrate 2. Substrate 2 is provided with a window 11,. through which a rear surface of membrane 3 is exposed. X-ray absorber 4 includes a transfer circuit pattern 10, i.e., a circuit pattern for transfer in a region located above window 11. X-ray absorber 4 includes an opening 7, which functions as an alignment mark and is located in a region not overlapping with window 11 in a plan view, i.e., a region outside window 11. Since opening 7 functioning as the alignment mark is formed in X-ray absorber 4 as described above, it is not necessary to form a film of gold or the like functioning as the alignment mark on X-ray absorber 4 in contrast to the X-ray mask proposed in the prior art. Therefore, the X-ray mask provided with the alignment mark can be produced without an additional step of forming a film of gold or the like. In a process of manufacturing the X-ray mask which will be described later, a step of forming the transfer circuit pattern on X-ray absorber 4 can be performed using opening 7 for detecting the position on the X-ray mask. Therefore, the transfer circuit pattern having a high position accuracy can be formed. Opening 7 is situated in the region spaced from the region wherein transfer circuit pattern 10 is formed, and more specifically in a region, under which substrate 2 is present with membrane 3 therebetween. Therefore, significant change in position of opening 7 can be prevented in the step of writing the mask pattern for forming transfer circuit pattern 10, even when membrane 3 situated on window 11 vibrates or a distortion occurs due to resist stress relief or heat caused by the step of writing the mask pattern. Consequently, it is possible to prevent lowering of the accuracy of position detection of the X-ray mask, which may be caused by change in position of opening 7. Therefore, the transfer circuit pattern having a high position accuracy can be formed. A process of manufacturing the X-ray mask of the embodiment 1 of the invention shown in FIG. 1 will now be described below with reference to FIGS. 2 to 6. As shown in FIG. 2, membrane 3 of 1-3 .mu.m in thickness is first formed on substrate 2. X-ray absorber 4 is formed on membrane 3. A resist 5 is applied over X-ray absorber 4. Support ring 1 is disposed under substrate 2. Substrate 2 is partially removed by etching to form window 11 exposing the rear surface of membrane 3. As shown in FIG. 3, exposure with light and development are effected to form an alignment mark pattern 6, i.e., a pattern for the alignment mark in resist 5. In this step, alignment mark pattern 6 is formed in a region which does not overlap with window 11 in a plan view and, in other words, is located outside window 11. As described above, the step of forming alignment mark pattern 6 uses the light exposing method requiring a shorter exposure time than an exposing method with an electron beam, which is employed for forming the transfer circuit pattern to be described later. Therefore, the time required for manufacturing the X-ray mask can be reduced compared with the case where the electron beam writing method is used for writing both alignment mark pattern 6 and the transfer circuit pattern on the resist. The step of forming alignment mark pattern 6 may use the exposing method using the electron beam. Thereafter, X-ray absorber 4 masked with resist 5 is partially removed by etching to form opening 7 functioning as the alignment mark. Thereafter, resist 5 is removed. Through the above steps, the structure shown in FIG. 4 is formed. As described above, opening 7 functioning as the alignment mark is formed in X-ray absorber 4. Therefore, the process of manufacturing the X-ray mask can be simplified by eliminating a film forming step or deposition step required in the conventionally proposed method, in which a film of gold or the like is formed on X-ray absorber 4, and the alignment mark is formed by patterning this film of gold or the like by etching. Then, resist 8 is applied over X-ray absorber 4 as shown in FIG. 5. Then, the position of opening 7 functioning as the alignment mark is detected with an electron beam or the like emitted to opening 7. Based on this position information, the positions of X-ray absorber 4 and resist 8 are detected, and the transfer circuit pattern is written on resist 8 by the electron beam writing method while detecting the positions in this manner. By developing resist 8 thus written, transfer circuit pattern 9 is formed on resist 8 as shown in FIG. 6. As described above, transfer circuit pattern 9 is formed using opening 7, which functions as the alignment mark, for position detection of X-ray absorber 4 and resist 8. Therefore, the accuracies of position and size of the transfer circuit pattern 9 can be improved. Opening 7 is located in the region which is spaced from the region bearing transfer circuit pattern 9, and is situated over substrate 2 with membrane 3 therebetween. Therefore, significant change in position of opening 7 can be prevented in the step of writing the transfer circuit pattern, even when membrane 3 situated on window 11 vibrates or a distortion occurs due to resist stress relief or heat caused by the step of writing the transfer circuit pattern. Consequently, it is possible to prevent deterioration of the accuracy of position detection of the X-ray mask due to change in position of opening 7. Therefore, transfer circuit pattern 9 having a high position accuracy can be formed. Accordingly, the X-ray mask provided with the transfer circuit pattern having a high position accuracy can be manufactured. Then, X-ray absorber 4 masked with resist 8 is partially removed to form transfer circuit pattern 10 (see FIG. 1). Thereafter, resist 8 is removed. In this manner, the X-ray mask according to the embodiment 1 of the invention shown in FIG. 1 can be manufactured. (Embodiment 2) Referring to FIGS. 7 to 10, description will now be given on steps of manufacturing the X-ray mask of an embodiment 2 of the invention. First, a structure shown in FIG. 7 is produced through steps similar to those of manufacturing the X-ray mask of the embodiment 1 of the invention shown in FIG. 2. The X-ray mask in the first step of the process of manufacturing the X-ray mask according to the embodiment 2 of the invention shown in FIG. 7 basically has the same structure as the X-ray mask in the first step of the process of manufacturing the X-ray mask of the embodiment 1 of the invention shown in FIG. 2. In the step of manufacturing the X-ray mask of the embodiment 2 of the invention shown in FIG. 7, however, a resist 16 formed on X-ray absorber 4 is thicker than resist 5 in the step of manufacturing the X-ray mask of the embodiment 1 of the invention shown in FIG. 2. This is because resist 16 is used in both the step of forming opening 7 (see FIG. 9) functioning as the alignment mark and the step of forming transfer circuit pattern 10 (see FIG. 1), and therefore must endure the etching in these two steps. As shown in FIG. 8, light exposure is performed on resist 16 to form alignment mark pattern 6. In this step, alignment mark pattern 6 is formed in a region not overlapping with window 11, i.e., a region outside window 11, as is done also in the embodiment 1 of the invention. Since the light exposure is performed for forming alignment mark pattern 6, this can achieve an effect similar to that in the case where the light exposure is performed for forming alignment mark pattern 6 on resist 5 in the step of manufacturing the X-ray mask of the embodiment 1 of the invention shown in FIG. 3. Electron beam exposure may be employed for forming alignment mark pattern 6. Then, as shown in FIG. 9, X-ray absorber 4 masked with resist 16 is partially removed by etching to form opening 7 functioning as the alignment mark. Then, as shown in FIG. 10, the position of opening 7 functioning as the alignment mark is detected with an electron beam or the like emitted to opening 7. Based on this position information, the positions of X-ray absorber 4 and resist 16 are detected, and the transfer circuit pattern is written on resist 16 by the electron beam writing method while detecting the positions in this manner. By developing resist 16 after the above writing, transfer circuit pattern 9 is formed on resist 16. As described above, alignment mark pattern 6 for forming opening 7 and transfer circuit pattern 9 for forming transfer circuit pattern 10 (see FIG. 1) are written on the same resist 16. Therefore, one of the steps of forming the resists in the embodiment 1 of the invention can be eliminated. Accordingly, in addition to the effect achieved by the embodiment 1 of the invention, such an effect can be achieved that the X-ray mask provided with the transfer circuit pattern having a high position accuracy can be produced through further simplified steps. Thereafter, X-ray absorber 4 masked with resist 16 is partially removed by etching to form transfer circuit pattern 10 (see FIG. 1). By removing resist 16, the X-ray mask shown in FIG. 1 can be manufactured. (Embodiment 3) Referring to FIGS. 11 and 12, description will be given on the process of manufacturing an X-ray mask of an embodiment 3 of the invention. After performing the steps of manufacturing the X-ray mask of the embodiment 1 of the invention shown in FIGS. 2 to 4, resist 8 is formed only on a region of X-ray absorber 4 located above window 11 and, more specifically, a region where the transfer circuit pattern is to be formed. Thus, resist 8 exposing opening 7 is formed on X-ray absorber 4. Resist 8 may be formed in such a manner that a resist is first applied over an entire surface of X-ray absorber 4, and then the resist is removed from a peripheral portion covering opening 7. By removing the resist from an area on opening 7, opening 7 is exposed. As shown in FIG. 12, resist 8 formed only in the region over window 11 may have a circular form or may have a square form similar to the form of window 11. Instead of entirely removing the resist from the peripheral portion of X-ray absorber 4, the resist may be removed only from a region above and near opening 7, in which case a similar effect can be achieved. The position of opening 7 functioning as the alignment mark is detected with an electron beam or the like emitted to opening 7. Based on this position information, the positions of X-ray absorber 4 and resist 8 are detected, and the transfer circuit pattern is written on resist 8 by the electron beam writing method while detecting the positions in this manner. The resist is not present above opening 7 functioning as the alignment mark. Therefore, such a problem can be prevented that characteristics of the resist are deteriorated due to irradiation with the light or electron beam for detecting the alignment mark, and thereby detection of opening 7 is impeded. Consequently, the position of opening 7 functioning as the alignment mark can be performed accurately. Thereby, the transfer circuit pattern having a high accuracy can be formed. This embodiment 3 may be applied to the embodiment 2, in which case a similar effect can be achieved. (Embodiment 4) Referring to FIG. 13, the X-ray mask according to the embodiment 4 of the invention will now be described below. Referring to FIG. 13, the X-ray mask according to the embodiment 4 of the invention basically has the same structure as the X-ray mask of the embodiment 1 of the invention shown in FIG. 1. However, in the X-ray mask of the embodiment 4 of the invention shown in FIG. 13, an etching stopper 12, which is made of a material different in etching rate from X-ray absorber 4, is arranged between membrane 3 and X-ray absorber 4 for an etching step which is performed for forming opening 7 and transfer circuit pattern 10. Since etching stopper 12 is employed as described above, damage to membrane 3 by the etching can be prevented in the etching step for forming opening 7 functioning as the alignment mark and transfer circuit pattern 10. Since opening 7 is formed in the region not overlapping with window 11 in the plan view, this embodiment can achieve an effect similar to that by the X-ray mask of the embodiment 1 of the invention shown in FIG. 1. Referring to FIGS. 14 to 20, steps of manufacturing the X-ray mask of the embodiment 4 of the invention will be described below. As shown in FIG. 14, membrane 3 is formed on substrate 2. Window 11 exposing the rear surface of membrane 3 is formed in substrate 2. Support ring 1 is arranged under substrate 2. Etching stopper 12 is formed on membrane 3. X-ray absorber 4 is formed on etching stopper 12. An etching mask 13 is formed on X-ray absorber 4. Resist 5 is formed on etching mask 13. As shown in FIG. 15, alignment mark pattern 6 is formed in the region of resist 5 not overlapping with window 11 in the plan view by the light exposing method. In this step, alignment mark pattern 6 may be formed by an electron beam exposing method. Etching mask 13 masked with resist 5 is partially removed by etching to form an alignment mark pattern 14 in etching mask 13 (see FIG. 16). Thereafter, resist 5 is removed. In this manner, the structure shown in FIG. 16 is formed. Then, as shown in FIG. 17, X-ray absorber 4 masked with etching mask 13 is partially removed by etching to form opening 7 functioning as the alignment mark. As shown in FIG. 18, resist 8 is applied over etching mask 13. Then, as shown in FIG. 19, the position of opening 7 functioning as the alignment mark is detected with an electron beam or the like emitted to opening 7. Based on this position information, the positions of resist 8 and others are detected, and transfer circuit pattern 9 is formed on resist 8 by the electron beam writing method while detecting the positions in this manner. Etching mask 13 masked with resist 8 is partially removed to form a transfer circuit pattern 15 in etching mask 13 (see FIG. 20). Thereafter, resist 8 is removed. In this manner, the structure shown in FIG. 20 is formed. X-ray absorber 4 masked with etching mask 13 is partially removed by etching to form transfer circuit pattern 10 (see FIG. 13). Thereafter, etching mask 13 is removed so that the X-ray mask shown in FIG. 13 is formed. As shown in FIGS. 17 and 20, etching mask 13 and etching stopper 12 are subjected two times to the etching in the process of forming opening 7 and transfer circuit pattern 10 (see FIG. 13). Therefore, etching mask 13 and etching stopper 12 must have film thicknesses which can endure the etching performed two times. For example, it is now assumed that X-ray absorber 4 has a film thickness of 500 nm, the rate of overetching in the first etching process is 20%, and the selection ratio of X-ray absorber 4 with respect to etching mask 13 and etching stopper 12 is 10 when etching X-ray absorber 4. In this case, the required thicknesses of etching mask 13 and etching stopper 12 can be calculated as follows. Etching mask 13 is first discussed. In the etching step for forming opening 7 functioning as the alignment mark shown in FIG. 17, the thickness reduced by this etching is 600 nm when calculated based on X-ray absorber 4, because X-ray absorber 4 is 500 nm in thickness and the overetching rate thereof is 20%. Since the selection ratio of X-ray absorber 4 with respect to etching mask 13 is 10, the thickness of etching mask 13 removed in this etching step is 60 nm. In the etching step for forming transfer circuit pattern 10, the thickness of etching mask 13 reduced thereby is equal to the foregoing value, and thus is 60 nm. Therefore, etching mask 13 must have a thickness of 120 nm or more. Meanwhile, etching stopper 12 is etched as follows. In the etching step for forming opening 7 shown in FIG. 17, a portion of etching stopper 12 forming the bottom of opening 7 is subjected to the etching correspondingly to the overetching quantity. Therefore, the thickness of etching stopper 12 reduced in the first etching step is 10 nm. In the etching step for forming transfer circuit pattern 10, etching stopper 12 is subjected to the etching to remove its portion forming the bottom of transfer circuit pattern 10 correspondingly to the overetching quantity, similarly to the first etching step. Thus, the portion of etching stopper 12 forming the bottom of transfer circuit pattern 10 is removed by 10 nm. Meanwhile, etching stopper 12 is exposed at the bottom of opening 7 even at the start of the etching step for forming transfer circuit pattern 10. Therefore, etching stopper 12 is subjected to the etching similarly to etching mask 13. Accordingly, the thickness of etching stopper 12 removed by this etching step is 60 nm which is equal to the reduced thickness of etching mask 13. Therefore, the total thickness of etching stopper 12 reduced by the foregoing two etching steps is largest at the bottom of opening 7, and is equal to 70 nm. Thus, according to the process of manufacturing the X-ray mask of the embodiment 5 of the invention, etching stopper 12 must have a thickness of 70 nm or more. Further, in the etching step of forming opening 7 functioning as the alignment mark shown in FIG. 17, the etching conditions may be adjusted such that a selection ratio of X-ray absorber 4 with respect to etching mask 13 and etching stopper 12 is 100, whereby it is possible to reduce thicknesses of etching mask 13 and etching stopper 12 which are reduced in the above etching step. As a result, it is possible to reduce the required thicknesses of etching mask 13 and etching stopper 12. Under the above conditions, the etching step of forming opening 7 reduces the thickness of etching mask 13 by 6 nm, and also reduces the thickness of etching stopper 12 by 1 nm. If the foregoing conditions are employed in the etching step of forming transfer circuit pattern 10, the required minimum thickness of etching mask 13 is 66 nm, and the required minimum thickness of etching stopper 12 is 61 nm. If there is a difference between the size of opening 7 functioning as the alignment mark and the size of the interconnection pattern and others formed in transfer circuit pattern 10, the etching conditions for forming opening 7 may be determined depending on the size thereof, and thus may be independent of the etching conditions for forming transfer circuit pattern 10 which is determined depending of the size of the interconnection pattern and others. Thereby, both opening 7 and transfer circuit pattern 10 can be formed with high size accuracies. As a result, the X-ray mask provided with the transfer circuit pattern having a high position accuracy can be produced. The etching conditions for forming opening 7 may be adjusted such that the accuracy of the pattern configuration is not extremely high, but the selection ratio of X-ray absorber 4 with respect to etching mask 13 and etching stopper 12 is sufficiently large (e.g., 100). The etching conditions for forming transfer circuit pattern 10 may be adjusted such that the selection ratio of X-ray absorber 4 with respect to etching mask 13 and etching stopper 12 is not significantly high, but the accuracy of pattern configuration is sufficiently high. Thereby, it is possible to produce the X-ray mask provided with the transfer circuit pattern having a high position accuracy while reducing the required thicknesses of etching mask 13 and etching stopper 12. (Embodiment 5) Referring to FIGS. 21 to 26, description will now be given on a process of manufacturing an X-ray mask according to an embodiment 5 of the invention. The structure which is shown in FIG. 21 and is the same as that shown in FIG. 14 is formed through a manufacturing step similar to that for forming the structure of the X-ray mask shown in FIG. 14. However, in the process of manufacturing the X-ray mask of the embodiment 5 of the invention shown in FIG. 21, resist 16 is used in both the step of forming opening 7 functioning as the alignment mark and the step of forming transfer circuit pattern 10, as will be described later. Therefore, resist 16 is thicker than that in the manufacturing process of the embodiment 4 of the invention. As shown in FIG. 22, alignment mark pattern 6 is formed in resist 16 similarly to the process of manufacturing the X-ray mask of the embodiment 4 of the invention shown in FIG. 15. Etching mask 13 masked with resist 16 is partially removed to form alignment mark pattern 14 in etching mask 13. In this manner, the structure shown in FIG. 23 is formed. Then, as shown in FIG. 24, X-ray absorber 4 masked with resist 16 and etching mask 13 is partially removed by etching to form opening 7. As shown in FIG. 25, transfer circuit pattern 9 is formed on resist 16 by the electron beam writing. As described above, alignment mark pattern 6 and transfer circuit pattern 9 are formed in resist 16. Therefore, the manufacturing process can be simpler than that in the embodiment 4 of the invention which requires the step of forming the resist to be performed twice. Etching mask 13 masked with resist 16 is partially removed by etching to form transfer circuit pattern 15 in etching mask 13. Thereafter, resist 16 is removed to form the structure shown in FIG. 26. Thereafter, X-ray absorber 4 masked with etching mask 13 is partially removed by etching to form transfer circuit pattern 10 (see FIG. 13) in X-ray absorber 4. Thereafter, etching mask 13 is removed so that the X-ray mask shown in FIG. 13 is produced. If there is a difference between the size of opening 7 and the size of the interconnection pattern and others formed in transfer circuit pattern 10, the etching conditions for forming opening 7 may be determined depending on the size thereof, and thus may be independent of the etching conditions for forming transfer circuit pattern 10 which is determined depending of the size of the interconnection pattern and others. Thereby, an effect similar to that of the embodiment 4 of the invention can be achieved. The concept of the invention can be applied to the electron beam writing (EB writing) for directly writing a circuit pattern on a resist on a semiconductor substrate with an electron beam. The electron beam writing requires an alignment mark, which is prepared, in the prior art, by depositing a film on the semiconductor substrate and by forming the alignment mark from this film. However, this film forming process can be eliminated by employing the concept of the invention and forming the opening functioning as the alignment mark in the semiconductor substrate. Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims.
	summary
	description	The present invention relates to an improved system for use with an ion implanter that reduces deposition rates of materials and hence extends the maintenance schedule. Less flaking of materials do to build up between maintenance schedules is also achieved. Ion implanters can be used to treat silicon wafers by bombardment of the wafers with an ion beam. One use of such beam treatment is to selectively dope the wafers with impurities of a controlled concentration to yield a semiconductor material during fabrication of a integrated circuits. A typical ion implanter includes an ion source, an ion extraction device, a mass analysis device, a beam transport device and a wafer processing device. The ion source generates ions of desired atomic or molecular dopant species. These ions are extracted from the source by an extraction system, typically a set of electrodes that energize and direct the flow of ions from the source. The desired ions are separated from byproducts of the ion source in a mass analysis device, typically a magnetic dipole performing mass dispersion of the extracted ion beam. The beam transport device, typically a vacuum system containing an optical train of focusing devices transports the ion beam to the wafer processing device while maintaining desired optical properties of the ion beam. Finally, semiconductor wafers are implanted in the wafer processing device. Batch processing ion implanters include a spinning disk support for moving multiple silicon wafers through the ion beam. The ion beam impacts the wafer surface as the support rotates the wafers through the ion beam. Serial implanters treat one wafer at a time. The wafers are supported in a cassette and are withdrawn one at time and placed on a support. The wafer is then oriented in an implantation orientation so that the ion beam strikes the single wafer. These serial implanters use beam shaping electronics to deflect the beam from its initial trajectory and often are used in conjunction with coordinated wafer support movements to selectively dope or treat the entire wafer surface. Faraday flags are used to measure beam current. These flags are periodically inserted into an ion beam either upstream of the implantation chamber or at a region behind a workpiece support to monitor beam current. U.S. Pat. No. 6,992,309 to Petry et al. illustrates a dosimetry system having a faraday flag that is mounted for movement along a controlled path. The disclosure of the '309 patent is incorporated herein by reference. The disclosed system is based on studies done relating to material deposition on the apparatus of the faraday flag and surrounding structure, which was found to be a function of temperature. Studies concerning steady state beam power as a function of implanter component temperature have shown a relation between deposition rate of impurities in the region of the faraday flag and component temperature. These studies show that the deposition rate is reduced (at a quadratic rate) as component (substrate) temperature increases. These studies predict a ninety percent decrease in the deposition rate as the temperature increases from 20 degrees C. to 270 degrees C. It has been observed that flag faraday graphite target temperatures can reach over 1000 degrees Celsius when subjected to a high power beam flux. This temperature increase is due to an inability for heat to dissipate away from the faraday flag. Prior art flag targets rely on radiation for heat dissipation. Heat loses through conduction and convection are limited due to the flags position in a highly evacuated region of the implanter. There is a need to remove heat resulting with a high beam flux impinging on the graphite target and thereby control component temperatures in the implanter. Further, there is a need to reduce sputter material resulting from ion bombardment on the faraday flag assembly. One exemplary system includes a source, beam transfer structure and a workpiece support defining a path of travel for ions that impinge on one or more workpieces at an implantation station. A faraday flag structure has a conductive strike plate coupled to a circuit for monitoring ions striking the strike plate to obtain an indication of the ion beam current. A base supports the strike plate and includes a thermally conductive material surrounding at least a portion of an outer perimeter of the strike plate to conduct heat energy away from the strike plate. Located below the strike plate is a cold trap, which is a thermally regulated structure. The cold trap is designed to attract sputterred material and reduce film buildup within the ion implanter, thus improving the quality of the finished product and reducing cleaning and maintenance schedules within the ion implantation system. Further features of the disclosure will become apparent to those skilled in the art to which the present invention relates from reading the following specification with reference to the accompanying drawings. Turning to the drawings, FIG. 1 illustrates a schematic depiction of an ion beam implanter 10. The implanter includes an ion source 12 for creating ions that form an ion beam 14 which is shaped and selectively deflected to traverse a beam path to an end or implantation station 20. The implantation station includes a vacuum or implantation chamber 22 defining an interior region in which a workpiece 24 such as a semiconductor wafer is positioned for implantation by ions that make up the ion beam 14. Control electronics indicated schematically as a controller 41 are provided for monitoring and controlling the ion dosage received by the workpiece 24. Operator input to the control electronics are performed via a user control console 26 located near the end station 20. The ions in the ion beam 14 tend to diverge as the beam traverses a region between the source and the implantation chamber. To reduce this divergence, the region is maintained at low pressure by one or more vacuum pumps 27. The ion source 12 includes a plasma chamber defining an interior region into which source materials are injected. The source materials may include an ionizable gas or vaporized source material. Ions generated within the plasma chamber are extracted from the chamber by ion beam extraction assembly 28, which includes a number of metallic electrodes for creating an ion accelerating electric field. Positioned along the beam path 14 is an analyzing magnet 30 which bends the ion beam 14 and directs it through a beam shutter 32. Subsequent to the beam shutter 32, the beam 14 passes through a quadrupole lens system 36 that focuses the beam 14. The beam then passes through a deflection magnet 40, which is controlled by the controller 41. The controller 41 provides an alternating current signal to the conductive windings of the magnet 40 which in turn caused the ion beam 14 to repetitively deflect or scan from side to side at a frequency of several hundred Hertz. In one disclosed embodiment, scanning frequencies of 200 to 300 Hertz are used. This deflection or side to side scanning generates a thin, fan shaped ribbon ion beam 14a. Ions within the fan shaped ribbon beam follow diverging paths after they leave the magnet 40. The ions enter a parallelizing magnet 42 wherein the ions that make up the beam 14a are again bent by varying amounts so that they exit the parallelizing magnet 42 moving along generally parallel beam paths. The ions then enter an energy filter 44 that deflects the ions downward (y-direction in FIG. 1) due to their charge. This removes neutral particles that have entered the beam during the upstream beam shaping that takes place. The ribbon ion beam 14a that exits the parallelizing magnet 42 is an ion beam with a cross-section essentially forming a very narrow rectangle that is, a beam that extends in one direction, e.g., has a vertical extent that is limited (e.g. approx ½ inch) and has an extent in the orthogonal direction that widens outwardly due to the scanning or deflecting caused to the magnet 40 to completely cover a diameter of a workpiece such as a silicon wafer. Generally, the extent of the ribbon ion beam 14a is sufficient to, when scanned, implant an entire surface of the workpiece 24. Assume the workpiece 24 has a horizontal dimension of 300 mm. (or a diameter of 300 mm.). The magnet 40 will deflect the beam such that a horizontal extent of the ribbon ion beam 14a, upon striking the implantation surface of the workpiece 24 within the implantation chamber 22, will be at least 300 mm. A workpiece support structure 50 both supports and moves the workpiece 24 (up and down in the y direction) with respect to the ribbon ion beam 14 during implantation such that an entire implantation surface of the workpiece 24 is uniformly implanted with ions. Since the implantation chamber interior region is evacuated, workpieces must enter and exit the chamber through a load lock 60. A robot 62 positioned within the implantation chamber 22 moves wafer workpieces to and from the load lock 60. A workpiece 24 is schematically shown in a horizontal position within the load lock 60 in FIG. 1. The robot 62 moves the workpiece 24 from the load lock 60 to the support 50 by means of an arm which reaches into the load lock 60 to capture a workpiece for movement within the evacuated region of the implantation chamber. Prior to implantation, the workpiece support structure 50 rotates the workpiece 24 to a vertical or near vertical position for implantation. If the workpiece 24 is vertical, that is, normal with respect to the ion beam 14, the implantation angle or angle of incidence between the ion beam and the normal to the workpiece surface is 0 degrees. In a typical implantation operation, undoped workpieces (typically semiconductor wafers) are retrieved from one of a number of cassettes 70-73 by one of two robots 80, 82 which move a workpiece 24 to an orienter 84, where the workpiece 24 is rotated to a particular orientation. A robot arm retrieves the oriented workpiece 24 and moves it into the load lock 60. The load lock closes and is pumped down to a desired vacuum, and then opens into the implantation chamber 22. The robotic arm 62 grasps the workpiece 24, brings it within the implantation chamber 22 and places it on an electrostatic clamp or chuck of the workpiece support structure 50. The electrostatic clamp is energized to hold the workpiece 24 in place during implantation. Suitable electrostatic clamps are disclosed in U.S. Pat. Nos. 5,436,790, issued to Blake et al. on Jul. 25, 1995 and U.S. Pat. No. 5,444,597, issued to Blake et al. on Aug. 22, 1995, both of which are assigned to the assignee of the present invention. Both the '790 and '597 patents are incorporated herein in their respective entireties by reference. After ion beam processing of the workpiece 24, the workpiece support structure 50 returns the workpiece 24 to a horizontal position and the electrostatic clamp is de-energized to release the workpiece. The arm 62 grasps the workpiece 24 after such ion beam treatment and moves it from the support 50 back into the load lock 60. In accordance with an alternate design the load lock has a top and a bottom region that are independently evacuated and pressurized and in this alternate embodiment a second robotic arm (not shown) at the implantation station 20 grasps the implanted workpiece 24 and moves it from the implantation chamber 22 back to the load lock 60. From the load lock 60, a robotic arm of one of the robots moves the implanted workpiece 24 back to one of the cassettes 70-73 and most typically to the cassette from which it was initially withdrawn. Faraday Flag A faraday flag 100 built in accordance with an exemplary embodiment has a graphite target or strike plate 110 mounted to a cup 112 which is a thermal control jacket described below that can be cooled or heated as appropriate. The thermal jacket is made from aluminum, a thermally conductive material that provides an efficient way for the heat to move into or out of the target or strike plate 110. The jacket is designed to accept different shape faraday flags. The principle of operation of the cooling jacket is as follows. A target of any shape is inserted into an appropriately dimensioned cup with a minimum clearance around the target. The cup is designed to maximize heat flow away from the target and is maintained at room temperature. A gasket may be designed into the structure depending on a compressibility and thermal conductivity requirement. When the target is heated it will expand, and will apply uniform pressure to a gasket between the target and the cup which will cause the gasket to deform thus improving thermal contact at the interface and reduce and control target temperature. The thermal jacket or cup utilizes conductive heating and/or cooling as a principle mechanism for heat transfer in a vacuum system. A mismatch in thermal expansion coefficients between the thermal jacket and the target material controls the contact pressure thus providing the ability to passively or actively control the target temperature. There are a number of ways to improve the interface conductivity either individually or in combination with one another. The thermal jacket may use thermal expansion to an applied load at the thermal interface and cause interface deformation and increase conductive heat transfer area. The thermal jacket may be designed with a preload at the thermal interface causing interface deformation and increase the conductive heat transfer area. The thermal jacket may be designed with a high vacuum compatible “thermal paste” to improve thermal conductivity between the strike plate and thermal jacket. Initial estimates based on the design illustrated in FIGS. 2 and 3 show that the graphite target temperature will peak at 405 k with 2000 watts of power input to the target. This assumes a perfect contact at the gasket interface. In contrast to the above illustration, where the cooling is absent, the target temperature can reach 1400 k with 2000 watts of power input to the target. A thermally controlled ion strike plate can be integrated into the ion implanter by incorporating the invention into the flag faraday assembly 150 of FIG. 4. This assembly 150 is for use with an ion source, beam transfer structure and a workpiece support defining a path of travel such as show in FIG. 1. In one embodiment (described below) there is a cold trap 200 utilized and in an alternate embodiment there is no cold trap. The faraday flag assembly 150 includes as a subcomponent the conductive strike plate coupled to a circuit (not shown) by a cable 151 that sends signals to the controller 41 for monitoring ions striking the strike plate to obtain an indication of the beam current. A base 114 supports the strike plate within a housing 152 which defines an entryway or channel 154 which allows ions in the beam to enter a housing interior and impact the strike plate. An elongated support 160 coupled to the housing 152 moves the strike plate in an out of a beam path of travel 162. Coolant supply and return lines 164 are routed through the support 160. The base 114 includes a cutout 170 that defines a coolant path 171 that includes coolant channels into which coolant is routed to maintain a temperature of the strike plate by dissipating heat away from said strike plate. In operation, during ion implantation of a workpiece 24 the faraday flag 100 is retracted from within the ion beam so that the ions in the beam 24 pass unimpeded through the region of the faraday flag 100 shown in FIG. 5 immediately downstream from a beam accelerator 181 to the implantation chamber 20. A motor (not shown) is actuated by the controller 41 to move the faraday flag 100 into the beam path from a region 180 it occupies during implantation. During the time the ions strike the strike plate 110 the coolant flows into and out of the faraday assembly 150 through the coolant supply and return lines 164 and through the coolant path 170 located in the base support 114 of the faraday flag 100. The temperature is regulated by, for example thermal couples that monitor the temperature and provide feedback for regulating the cooling supply 164. Cold Trap During beam tuning material will sputter from the graphite target 110 due to ion bombardment on the faraday flag assembly. While the heat dissipation system in the faraday flag assembly discussed above significantly reduces the material deposition rate, film buildup in the surroundings is further minimized by the introduction of a cold trap 200 shown in FIGS. 4 and 6. The addition of the cold trap 200 within the implantation chamber 22 provides a temperature gradient that reduces the film growth rate inside the chamber and in particular, along the ion beam path of travel 162 in the region of the faraday flag. The cold trap 200 is designed to have a surface with a high film deposition rate relative to other surfaces in the ion implantation system 10. Such design is achieved, as discussed below because of its low surface temperature (regulated to approximately 20 degrees Celsius), and because of its surface configuration which both attracts and retains particles. A temperature gradient of the system is designed to minimize film growth rate in the beam transport region. Heating cartridges 176 are inserted (typically at the top) into passageways 174 for heating the housing 152. These cartridges are energized by leads 177 controlled by the controller 41 and maintain the temperature of the housing at 300 degrees Celsius. In the embodiment of FIGS. 4 and 6 that utilizes a cold trap 200 cooling of the housing by coolant routed through the support 160 is not used. A preferred heater cartridge is commercially available from Watlow under the tradename Firerod®. The cold trap 200 shown in FIG. 6 can be composed from several different materials suitable for attracting material deposition and increasing the surface area and/or surface energy, such examples include textured and non-textured aluminum, graphite, porous aluminum, silicon carbide or silicon carbide foam (SiC foam). The cold trap 200 is typically located below a faraday flag assembly 100′, somewhat different from the earlier described embodiment with a strike plate at the rear of an open cup 212. The open cup 212 has a high temperature upper region 213 and a relatively cooler lower region 214. The temperature of the open cup 212 is controlled by a closed loop cooling system 210 for regulating the high and low temperature regions, 213 and 214 respectively. The open cup configuration depicted in FIG. 6 directs the sputter material 211 in a downward direction collecting on the cold trap surface 220. The surface 220 is designed to optimize collecting and retaining sputter material by having a textured surface. In the illustrated embodiment, a crenellating surface is shown having a series of ridges 221. By allowing the film to collect on the trap surface 220, the delamination of film sputter 211 and subsequent depositing on other surfaces within the ion implantation chamber 22 is reduced, allowing implanter maintenance schedules to be extended. The temperature of the cold trap 200 is regulated by a closed loop temperature controller having a number of coolant supply and return lines 222. While the illustrated embodiment depicts the cold trap 200 positioned below a open cup 212 faraday flag assembly 100′ sharing the same length and width, it should be appreciated by those skilled in the art that a cold trap could be any size and positioned at any location within the ion beam implanter 10 without departing from the spirit and scope of the claimed invention. Further, FIG. 6 illustrates the cold trap 200 being fixed to a base of the ion implantation chamber 22 by fasteners 225, but could be coupled to the faraday flag assembly 100 or a device such as the elongated support 160 that would move the cold trap 200 in and out of the beam path of travel 162, providing easy access for maintenance. It is understood that although an exemplary embodiment of the invention has been described with a degree of particularity, alterations and modifications from that embodiment are included which fall within the spirit or scope of the appended claims.
	claims	1. A method of observing cellular metabolism in vivo in a mammal, the method comprising the steps of:(a) administering a composition to the mammal comprising a positron emission tomography (PET) probe selected from the group consisting of 18F labelled:2-fluoro-2-deoxyarabinose;3-fluoro-3-deoxyarabinose;2-fluoro-2-deoxyribose;3-fluoro-3-deoxyribose;1-fluoro-1-deoxy-alpha-ribose; and1-fluoro-1-deoxy-beta-ribose;(b) allowing the probe to accumulate in cells in the mammal; and(c) observing the accumulated probe in the mammal using a positron emission tomography and a computed tomography (CT) process;so that cellular metabolism in the mammal is observed. 2. The method of claim 1, wherein the cellular metabolism that is observed in vivo comprises a metabolic profile observed in a pathological condition. 3. The method of claim 1, wherein the cellular metabolism that is observed in vivo comprises a metabolic profile observed in response to a therapeutic agent administered to the mammal. 4. The method of claim 1, wherein the mammal that is monitored has been administered an oxythiamine, an insulin, an metformin, a leflunomide or a methotrexate composition. 5. The method of claim 1, wherein:the mammal is a human;the PET probe consists of: (2-fluoro-2-deoxyarabinose); andcellular metabolism in liver, kidney, and/or intestinal tissues is selectively observed using a positron emission tomography process. 6. The method of claim 1, wherein probe that accumulates in the cells is phosphorylated by a ribokinase expressed by the cells. 7. A method of selectively observing a tissue or organ in vivo in a mammal, the method comprising the steps of:(a) administering a composition to the mammal comprising a positron emission tomography (PET) probe selected from the group consisting of ‘8F labelled:2-fluoro-2-deoxyarabinose;3-fluoro-3-deoxyarabinose;2-fluoro-2-deoxyribose;3-fluoro-3-deoxyribose;1-fluoro-1-deoxy-alpha-ribose; or1-fluoro-1-deoxy-beta-ribose;(b) allowing the probe to selectively accumulate in the tissue or organ; and(c) observing the accumulated probe in the mammal using a positron emission tomography and a computed tomography process;so that the tissue or organ is selectively observed in vivo in the mammal. 8. The method of claim 7, wherein the positron emission tomography probe is administered to the mammal in combination with a pharmaceutically acceptable compound comprising a diluent, a carrier, or a binding agent. 9. The method of claim 7, wherein the method observes cellular metabolism in liver, kidney, and/or intestinal tissues. 10. The method of claim 9, wherein the observed cellular metabolism is metabolism observed in at least one of:a metabolic disorder;tumor growth;gluconeogenesis;de novo nucleotide synthesisa neurodegenerative syndrome;a syndrome characterized by ischemia;a syndrome characterized by chronic inflammation;congestive heart failure; orstroke. 11. The method of claim 7, wherein the method observes a physiological activity in the tissue or organ that is observed in at least one of: tissue dysfunction; tissue regeneration; or tissue neoplasm. 12. The method of claim 1 or claim 7, wherein the positron emission tomography (PET) probe is 18F labelled 2-fluoro-2-deoxyarabinose. 13. The method of claim 7, wherein the positron emission tomography (PET) probe is 18F labelled 3-fluoro-3-deoxyarabinose. 14. The method of claim 1 or claim 7, wherein the positron emission tomography (PET) probe is 18F labelled 2-fluoro-2-deoxyribose. 15. The method of claim 1 or claim 7, wherein the positron emission tomography (PET) probe is 18F labelled 3-fluoro-3-deoxyribose. 16. The method of claim 1 or claim 7, wherein the positron emission tomography (PET) probe is 18F labelled 1-fluoro-1-deoxy-alpha-ribose. 17. The method of claim 1 or claim 7, wherein the positron emission tomography (PET) probe is 18F labelled 1-fluoro-1-deoxy-beta-ribose.
	description	Any and all applications for which a foreign or domestic priority claim is identified in the Application Data Sheet (either filed with the present application or subsequently amended) are hereby incorporated by reference under 37 CFR § 1.57. The present application is a continuation-in-part of U.S. patent application Ser. No. 16/450,447, filed Jun. 24, 2019. For clarity, the following are hereby incorporated by reference: U.S. patent application Ser. No. 15/444,299, filed Feb. 27, 2017, by the same inventor and with the same title, which claims priority to U.S. Provisional Patent Application Ser. No. 62/299,967, filed Feb. 25, 2016, by the same inventor and with the same title, and U.S. patent application Ser. No. 16/450,447, filed Jun. 24, 2019. The present invention relates generally to radiation attenuating material. More specifically, the present invention relates to radiation attenuating material for protection of the human body during medical procedures. During a medical imaging procedure, the human body in exposed to radiation that can damage critical anatomy of the patient's body. In order to mitigate the risk of exposure to these important areas, the use of heavy lead aprons have been adapted for use in the imaging area. These heavy lead aprons are cumbersome for the patient, operating room personnel, and technicians involved in the X-Ray process in hospitals and surgery centers. The lead apron can slide off of the patient's body as the patient is contorted into the position that facilitates the best image acquisition. This can prevent the acquisition of an image of the intended anatomy, as well as expose the aforementioned sensitive anatomy. Additionally, the lead aprons worn by doctors and technicians can similarly slide out of place and expose sensitive anatomy to harm as they maneuver around the patient to provide treatment and image capture. Further, current lead aprons are expensive due to overuse of lead in areas where radiation protection is unnecessary. Accordingly, it is desirable to have a garment system that effectively protects a person's anatomy, while allowing ease of movement. One embodiment of the invention includes a lightweight fabric with a built-in lead protection material. A radiation-attenuation garment system having a plurality of radiation-attenuating material panels adapted to conform to the contours of a body. The radiation-attenuation garment system includes a radiation attenuation shirt, comprising a front shirt portion, made of a compression material and a back shirt portion, made of a compression material. The front portion and the back portion are secured together to form a shirt, such that a first radiation-attenuating material panel may be removably disposed within the shirt, thereby protecting the wearer from radiation exposure in the areas having the radiation attenuation panels. The radiation-attenuation garment system may also include radiation-attenuation underwear shorts, comprising a front underwear shorts portion, made of a compression material and a back underwear shorts portion, made of a compression material. The front underwear portion and the back underwear portion may be secured together, or may be formed as a unitary garment (e.g., without seams) to form underwear shorts. A radiation-attenuating material panel may be removably disposed within the underwear shorts, thereby protecting the wearer from radiation exposure in the areas having the radiation attenuation panels. Other embodiments in accordance with the spirit and scope of the invention will become apparent to those of skill in the art. The present invention is directed to radiation-attenuating garments for medical personnel. FIG. 1 generally shows a layered, front view of one embodiment of the radiation-attenuating shirt. In FIG. 1, for example, there is shown a front shirt portion 19 of a radiation-attenuating shirt 10. The front shirt portion 19 is formed of compression fabric 14, such that the shirt 10 tightly adheres to a wearer and minimally restricts movement. Compression material 14 can be Spandex™, polyester blend, or any other material designed to stretch and retract such that a compression of the body is achieved. In another exemplary embodiment, compression material 14 can be a cooling, and/or moisture-wicking fabric, such as performance fabrics known in the art. Front shirt portion 19 includes a first pocket 12, wherein the pocket is formed by attaching a panel of compression material to front shirt portion on the bottom and sides of the panel of compression material. The unattached top portion of the first pocket 12 allows an object to be inserted between the front shirt portion 19 and the panel of compression material and be retained thereby. A radiation-attenuating material panel 16 prevents transmission of X-rays therethrough. Preferably, the radiation-attenuating material panel 16 is made of lead. However, the radiation attenuating material panel may also be a lead alloy or other material suitable to block or mitigate transmission of X-rays. Lead protection for direct beam 60 kV, 80 kV, 100 kV, and/or 0.5 millimeter lead equivalent is required for male and female reproductive parts. Lead protection for direct beam 60 kV, 80 kV, 100 kV, and/or 0.5 millimeter lead equivalent is required for male and female bone marrow. The radiation-attenuating material panels are adapted to conform to the contours of a body and can vary in size and shape to cover the requisite anatomy. Radiation-attenuating material panel 16 includes attaching mechanisms 18 on one of its sides. Radiation-attenuating material panel 16 may be removably inserted into first pocket 12. However, due to the weight of the radiation-attenuating material panel 16, a plurality of attaching mechanisms 18 are utilized to help retain radiation-attenuating material panel 16. For example, attaching mechanism 18 can be a fastener system including grommeted snaps. Alternatively, the attaching mechanisms can include Velcro™, buttons, snaps, ties, buckles, or any other mechanism for allowing removably coupling the radiation-attenuating material panel 16 to the front shirt portion 19. The front shirt portion 19, includes a plurality of attaching mechanisms disposed on one side of the front portion to attach to the plurality of attaching mechanisms 18 on the radiation-attenuating material panel 16. Referring to FIG. 2, there is shown a layered, rear view of one embodiment of the radiation-attenuating shirt. In FIG. 2, for example, there is shown a back shirt portion 28 of a radiation-attenuating shirt 10. The back shirt portion 28 is formed of compression fabric 14, such that the shirt 10 tightly adheres to a wearer and minimally restricts movement. Compression material 14 can be Spandex™, polyester blend, nylon, or any other material designed to stretch and retract such that a compression of the body is achieved. Back shirt portion 28 includes a second pocket 22, wherein the pocket is formed by attaching a panel of compression material to back shirt portion 28 on the bottom and sides of the panel of compression material. The unattached top portion of the second pocket 22 allows an object to be inserted between the back shirt portion 28 and the panel of compression material and be retained thereby. A second radiation-attenuating material panel 26 prevents transmission of X-rays therethrough. Preferably, the second radiation-attenuating material panel 26 is made of lead. However, the second radiation attenuating material panel 26 may also be a lead alloy or other material suitable to block or mitigate transmission of X-rays. Second radiation-attenuating material panel 26 includes attaching mechanisms 18 on one of its sides and is optimally shaped and sized for a wearer's back. Second radiation-attenuating material panel 26 can be removably inserted into second pocket 22. A plurality of attaching mechanisms 18 are utilized to help retain second radiation-attenuating material panel 26 in second pocket 22. For example, attaching mechanism 18 can be a fastener system including grommeted snaps. Alternatively, the attaching mechanisms can include Velcro™, buttons, snaps, buckles, ties, or any other mechanism for allowing removably coupling second radiation-attenuating material panel 26 to back shirt portion 28 and may also be operable to secure the second radiation-attenuating material panel 26 to the first radiation-attenuating material 16. The back shirt portion 28, includes a plurality of attaching mechanisms 18 disposed on one side of the front portion to attach to the plurality of attaching mechanisms 18 on second radiation-attenuating material panel 26. FIG. 3 shows a layered, front view of one embodiment of the radiation-attenuating underwear shorts 30. In FIG. 3, for example, there is shown a front underwear portion 36 of radiation-attenuating underwear shorts 30. The front underwear portion 36 is formed of compression fabric 14, such that the underwear 30 tightly adheres to a wearer and minimally restricts movement. Compression material 14 can be Spandex™, polyester blend, or any other material designed to stretch and retract such that a compression of the body is achieved. Front underwear portion 36 includes a first pocket 34, wherein the first pocket is formed by attaching a panel of compression material to front underwear portion 36 on the bottom and sides of the panel of compression material. The unattached top portion of the first pocket 34 allows an object to be inserted between the front underwear portion 36 and the panel of compression material allowing the object to be retained thereby. A first radiation-attenuating material panel 32 prevents transmission of X-rays therethrough. Preferably, the first radiation-attenuating material panel 32 is made of lead. However, the first radiation-attenuating material panel 32 may also be a lead alloy or other material suitable to block or mitigate transmission of X-rays. First radiation-attenuating material panel 32 includes attaching mechanisms 18 on one of its sides and is optimally shaped and sized for a wearer's pelvis. Shapes may include derivations for male and female anatomy. First radiation-attenuating material panel 32 can be removably inserted into first pocket 34. A plurality of attaching mechanisms 18 are utilized to help retain first radiation-attenuating material panel 32 in first pocket 34. For example, attaching mechanism 18 can be a fastener system including grommeted snaps. Alternatively, the attaching mechanisms can include Velcro™ buttons, or any other mechanism for allowing removably coupling first radiation-attenuating material panel 32 to front underwear portion 36. The front underwear portion 36, includes a plurality of attaching mechanisms 18 disposed on one side of the front portion to attach to the plurality of attaching mechanisms 18 on first radiation-attenuating material panel 32. FIG. 4 shows a layered, rear view of one embodiment of the radiation-attenuating underwear shorts 30. In FIG. 4, for example, there is shown a back underwear portion 46 of radiation-attenuating underwear shorts 30. The back underwear portion 46 is formed of compression fabric 14, such that the underwear 30 tightly adheres to a wearer and minimally restricts movement. Compression material 14 can be Spandex™, polyester blend, or any other material designed to stretch and retract such that a compression of the body is achieved. Back underwear portion 46 includes a second pocket 44, wherein the first pocket is formed by attaching a panel of compression material to back underwear portion 46 on the bottom and sides of the panel of compression material. The unattached top portion of the second pocket 44 allows an object to be inserted between the back underwear portion 46 and the panel of compression material allowing the object to be retained thereby. A second radiation-attenuating material panel 42 prevents transmission of X-rays therethrough. Preferably, the second radiation-attenuating material panel 42 is made of lead. However, the second radiation-attenuating material panel 42 may also be a lead alloy or other material suitable to block or mitigate transmission of X-rays. Second radiation-attenuating material panel 42 includes attaching mechanisms 18 on one of its sides and is optimally shaped and sized for a wearer's pelvis. Second radiation-attenuating material panel 42 can be removably inserted into second pocket 44. A plurality of attaching mechanisms 18 are utilized to help retain second radiation-attenuating material panel 42 in second pocket 44. For example, attaching mechanism 18 can be a fastener system including grommeted snaps. Alternatively, the attaching mechanisms can include Velcro™, buttons, or any other mechanism for allowing removably coupling second radiation-attenuating material panel 42 to back underwear portion 46. The back underwear portion 46, includes a plurality of attaching mechanisms 18 disposed on one side of the front portion to attach to the plurality of attaching mechanisms 18 on second radiation-attenuating material panel 42. Advantageously, the second radiation-attenuating material is lighter and cheaper than current options. By compressing the radiation attenuating material to the wearer, the present invention provides greater protection against slippage and exposure of vulnerable anatomy. While the present invention has been described in detail, it is not intended to be limited. Accordingly, various changes, variations, and substitutions may be made without departing with the scope of the invention as disclosed.
	claims	1. A container for a radioactive fluid, the container comprising:a body having a hollow inner chamber for containing the radioactive fluid, the chamber including an inner surface and an opening, a portion of the inner surface having a smooth burnished surface;a cap removably couplable to the body for sealing the opening, the cap having a plug that is insertable into the chamber through the opening, wherein the plug includes a groove; andan O-ring disposed within the groove of the plug,wherein an outer edge of the O-ring seats against the smooth burnished surface when the plug is fully received within the opening of the chamber,and wherein the body and the cap are made of a material substantially comprising a radiation shielding material. 2. The container of claim 1, wherein the burnished surface comprises a tapered burnished surface. 3. The container of claim 1, wherein with the plug fully received within the opening of the chamber, the cap is manually removable from the body. 4. The container of claim 1, wherein with the plug fully received within the opening of the chamber, the cap remains coupled to the body when pressure inside the chamber is higher than pressure outside the container by 7-15 psi. 5. The container of claim 1, wherein the O-ring comprises a silicone rubber. 6. The container of claim 1, wherein the radiation shielding material includes lead. 7. The container of claim 6, wherein the radiation shielding material substantially comprises lead and antimony. 8. The container of claim 1, wherein with the plug fully received within the opening of the chamber, the cap remains coupled to the body when the container is subjected to a temperature in the range of −40° C. to 70° C. 9. The container of claim 1, wherein the cap includes a manually gripable outer rim. 10. The container of claim 1, wherein the groove comprises a circumferential groove. 11. The container of claim 1, wherein the radioactive fluid comprises a radioactive gas. 12. A method of manufacturing a container for a radioactive fluid, the method comprising:forming a body having a hollow inner chamber for containing the radioactive fluid, the chamber including an inner surface and an opening;burnishing at least a portion of the inner surface of the chamber to form a burnished portion of the inner surface;forming a cap that is removably coupleable to the body for sealing the opening, the cap having a plug that is insertable into the chamber through the opening, wherein the plug includes a groove;coupling an O-ring to the cap by inserting the O-ring into the groove on the plug; andinserting the plug into the opening of the chamber until the plug is fully received within the opening and the O-ring is seated against the burnished portion of the inner surface of the chamber to form a fluid tight seal,wherein the body and the cap are made of a material substantially comprising a radiation shielding material. 13. The method of claim 12, wherein the step of forming the body comprises casting the body. 14. The method of claim 12, wherein the step of forming the cap comprises casting the cap. 15. The method of claim 12, wherein the step of burnishing comprises:inserting a burnishing tool into the chamber through the opening such that at least a portion of the burnishing tool contacts the inner surface of the chamber; androtating the burnishing tool relative to the body. 16. The method of claim 15, wherein the burnishing tool comprises a tapered outer surface. 17. The method of claim 15, wherein the burnishing tool comprises S7 tool steel. 18. The method of claim 12, wherein the radiation shielding material includes lead. 19. The method of claim 18, wherein the radiation shielding material substantially comprises lead and antimony. 20. The method of claim 12, wherein with the plug fully sealed with the burnished surface, the cap remains coupled to the body when pressure inside the container is higher than pressure outside the container by 7-15 psi. 21. The method of claim 12, wherein the groove comprises a circumferential groove. 22. The method of claim 12, wherein the radioactive fluid comprises a radioactive gas. 23. The method of claim 12, wherein the burnished portion comprises a tapered burnished portion.
	description	1 . . . probe 2 . . . cantilever 3 . . . cantilever oscillating means 4 . . . laser beam reflecting surface 5 . . . laser beams 7 . . . reflected laser beams 8 . . . optical position sensor 9 . . . specimen 10 . . . specimen moving means 11 . . . scanning operation 12 . . . upward and downward movements 13 . . . oscillations 14 . . . resonance point 21 . . . bump on specimen 61 . . . laser 62 . . . window 63 . . . vacuum container 64 . . . vacuum pump means 66 . . . laser moving means 67 . . . optical position sensor moving means 68 . . . gas introduction 69 . . . specimen stand moving means B, C, D . . . positions where reflected laser beams reach optical position sensor A, A0, A1, A2 . . . amplitudes of cantilever A-max . . . amplitude of resonance point on Q-curve f1, f2 . . . frequencies having a half amplitude of resonance point of Q-curve V1, xe2x88x92V1 . . . voltages applied to cantilever oscillating means W1, W2 . . . optical position output signal at optical position sensor According to the invention, a scanning probe microscope comprises a cantilever having a minute probe at one end thereof, a laser radiating laser beams to a laser beam reflecting surface of the cantilever, an optical position sensor detecting positions of reflected laser beams, specimen moving means moving a specimen, and cantilever oscillating means periodically oscillating the cantilever with a predetermined amplitude. The scanning probe microscope performs a first operation in which if the optical position sensor detects a reduced amplitude when the probe of the cantilever comes into contact with the specimen, uneven surface state data of the specimen are obtained on the basis of a control amount of movements of the specimen moving means which is moved upward or downward in order to maintain the reduced amplitude constant, and a second operation in which physical action force data of the specimen are obtained by keeping the probe spaced by a predetermined extent from the specimen on the basis of the uneven surface state data obtained by the first operation. In the first operation, the uneven surface state data are obtained by oscillating the cantilever with an oscillation frequency outside a frequency band which is a half value of a dependent curve (Q-curve) of the cantilever oscillating frequency and the amplitude. In the second operation, the cantilever is oscillated with a frequency near a resonant point of the dependent curve (Q-curve) of the cantilever oscillating frequency and the amplitude. [Embodiment] The invention will be described with reference to an embodiment shown in the accompanying drawings. FIGS. 1 to 3 schematically show a measurement performed by a scanning probe microscope of the invention. It is assumed that a specimen has an uneven surface as shown in FIG. 1. A cantilever 2 having a probe 1 is attached to cantilever oscillating means 3. Laser beams S are radiated onto a laser beam reflecting surface 4. Reflected laser beams 7 are detected as positions of an optical position sensor 8. The cantilever oscillating means 3 oscillates the cantilever 2 in order to move the probe 1 upward or downward. When the probe 2 comes into contact with the surface of a specimen 9, the reflected laser beams reach the position D of the optical position sensor. When the probe leaves from a dent of the specimen and moves upward to its maximum height, the reflected laser beams reach a position B of the optical position sensor. If the probe is in contact with or out of contact from the dent, the amplitude of the cantilever is derived as a difference between the positions D and B. Thereafter, when moved to the left by a scanning operation 11 of the specimen moving means 10, the probe comes into contact with or is out of contact from a bump. The reflected laser beans reach a position C of the optical position sensor when the probe is in contact with the bump. conversely, the reflected laser beams reach the position B while the probe is out of contact from the bump. When the probe oscillates to and from the bump of the specimen, the amplitude of the cantilever is obtained as the difference between the positions C and B. The uneven surface state of the specimen can be measured by detecting differences between the positions of the optical position sensor where the reflected laser beams reach. Further, the upward and downward movements 12 of the specimen moving means 10 may be controlled in order to make the difference between the positions, where the reflected beams reach the optical position sensor, constant. The uneven surface state data of the specimen may be obtained on the basis of a control amount of the upward and downward movements. Still further, it is preferable that the probe be brought into contact with the specimen with as small and as constant force as possible, which protects the probe and the specimen against damage. Usually, the latter method has been adopted. FIG. 2 schematically shows the oscillation of the cantilever which is attached to the cantilever moving means 3. The cantilever moving means 3 is constituted by a piezoelectric element, to which a constant voltage is periodically applied. The piezoelectric element generates vertical oscillations 13 in order to oscillate the cantilever 2, which oscillates with a certain amplitude A. The amplitude A depends upon the voltage applied to the piezoelectric element and the oscillation frequency of the piezoelectric element. Even if the applied voltage is constant, the amplitude A largely depends upon the oscillation frequency. A graph in FIG. 3 shows a difference between a cantilever oscillating frequency in the first operation of the present invention and a lever oscillating frequency in the related art. The ordinate denotes the amplitude A of the cantilever while the abscissa denotes the cantilever oscillating frequency. As the oscillating frequency f is increased from a low frequency, the amplitude A becomes maximum, i.e. A max, at a certain frequency. If the oscillating frequency f is further increased, the amplitude A becomes smaller. The frequency at which the amplitude A is at its maximum depends upon the material, length, depth and width of the cantilever. A frequency dependent curve of the amplitude A is called a xe2x80x9cQ-curvexe2x80x9d. A peak of the Q-curve is a resonance point 14. The oscillating frequency at the resonance point is a resonance frequency. When oscillated with a frequency in front of or behind the resonance frequency (near the resonance point 14), the cantilever is quickly oscillated but is slow to damp. In such a case, even if the same constant voltage is applied, the amplitude A of the cantilever becomes larger and is quickly oscillated, but takes time to damp. If the probe is affected by the specimen, the cantilever is slow to damp, so that the amplitude A of the cantilever does not become a target value, In the related art, the cantilever is oscillated at the frequency near the resonance point because ease of oscillation is preferred. It is assumed here that A-max denotes height (amplitude) of the resonance point 14, and that frequencies f1 and U on the Q-curve are a half of A-max. A frequency band between frequencies f1 and f2 has a half value. In this frequency band, the nearer the resonance point 14, the more easily the cantilever oscillates and the more slowly it damps. In the first operation of this embodiment, or the data acquisition process, the cantilever oscillating frequencies are at the opposite sides of the half value frequency band. outside the half value frequency band, the cantilever is slow to oscillate and is quick to damp. The oscillating frequency is set in the range where the cantilever is easy to damp. In this case, even when the amplitude of the cantilever varies with the uneven surface state of the specimen, the cantilever is quick to damp, and the amplitude of the cantilever changes but quickly becomes constant. Further, an amount of upward and downward movements of the specimen moving means can be controlled in accordance with the uneven surface state. Therefore, the data obtained on the basis of the moving amount of the specimen moving means can represent the uneven surface state of the specimen. In short, the uneven surface state of the specimen can be accurately measured. FIG. 4 schematically shows the relationship between the amplitude of the cantilever and the surface of the specimen when the uneven surface state is measured in a vacuum in order that the amplitude of the cantilever remains constant. When the probe is not in contact with the surface of the specimen, the cantilever oscillates with amplitude A0. It is assumed that as the specimen is moved to the left by the scanning operation 11 of the specimen moving means 10, the probe comes into contact with a bump 21 of the specimen, and the cantilever oscillates with amplitude A1. The amplitude A1 is smaller than the amplitude A0. For convenience of explanation, the control operation is assumed to have started when the cantilever oscillates with the amplitude A1. The upward and downward movements 12 of the specimen moving means 10 are controlled during the scanning operation in order to make the amplitude A1 of the cantilever constant. Needless to say, the uneven surface state of the specimen is measured on the basis of the controlled amount of the upward and downward movements of the cantilever as described previously. The specimen is moved further to the left in response to the scanning operation. At the instant the probe leaves the right edge of the bump 21, there is no surface which is as high as the bump. Therefore, the amplitude of the cantilever varies from A1, but remains unstable since the cantilever is slow to damp. If the amplitude quickly becomes stable in this state, the amount to control the upward and downward movements of the specimen moving means can be determined. If the specimen is moved close to the probe by the specimen moving means until the amplitude of the cantilever becomes A1, height of Me bump can be determined on the basis of the controlled amount of the upward and downward movements. However, when passing over the right edge of the bump, the probe has suddenly nothing to come into contact with. As a result, the cantilever starts to oscillate with different amplitudes. Since there is no air resistance around the cantilever, the cantilever is slow to damp, so that te amplitude of the cantilever does not become constant immediately. Actually, the amplitude becomes A2 in a certain time period and remains constant when the probe comes into contact with a dent of the specimen. The amplitude A2 is compared with the target amplitude A1. The control amount of the specimen moving means is determined in order to make the amplitude A2 equal to the amplitude A1. Actually speaking, the operation for determining the control amount of the specimen moving means is continuously in progress, so that the control amount is determined on the basis of data obtained while the amplitude is reaching A2. In other words, the control amount of the upward and downward movements is determined even when the probe is not in contact with the specimen. The uneven surface state data obtained in accordance with the transient amplitude of the cantilever do not represent the actual surface shape of the specimen but are affected by the cantilever, which is slow to damp. For instance, the amplitude of the cantilever does not follow the uneven surface state of the specimen at leading and trailing edges of a bump since the cantilever is slow to damp. Since the control amount of the upward and downward movements is determined in a transiently delayed state, the obtained uneven surface state data differ from the actual surface shape of the specimen as shown in FIG. 5. In the vacuum, the oscillation of the cantilever is quick to damp since the cantilever oscillating frequency is outside the half value frequency band of the Q-curve in the first operation as shown in FIG. 3. Specifically, in a vacuum, the cantilever can easily oscillate due to the absence of air, and is slow to damp once it oscillates. In other words, the uneven surface state data can be as accurately obtained in the vacuum as in the air since the cantilever oscillating frequency is set outside the half value frequency band of the Q-curve. In the second operation, or the measurement process, the probe is maintained spaced by the predetermined extent on the basis of the surface state data obtained in the first operation. Further, the cantilever oscillating frequency is changed to the frequency near the resonant point. FIG. 6 shows the time-dependent relationship between a waveform of voltages applied to the cantilever oscillating means and positions of optical position output signals detected by the optical position sensor. If there is no interaction between the probe and the specimen surface, the waveform of the applied voltages and optical position output waveform are free from time delays and are identical. However, the a probe and the specimen surface respond with the time delay because of electrostatic force, magnetic force or the like. It is assumed that a voltage V1 is applied in order to let the probe leave from the specimen surface, and that a voltage xe2x88x92V1 is applied in order to let the probe come close to the specimen surface. Further, it is assumed that an optical output signal W1 is issued in order to make the probe come close to the specimen surface and that an optical output signal W2 is issued in order to make the probe leave from the specimen surface. Since there is the foregoing interaction between the probe and the specimen surface, the optical position output signal W2 is issued after T seconds even if the applied voltage is V1. In other words, if the specimen surface has action force because of physical properties thereof, the probe tends to leave therefrom with a time delay (i.e. phase). Levels of the physical properties of the specimen surface can be compared by detecting length of the time delay. When the probe is not in contact with the specimen surface, the cantilever oscillating frequency is determined outside the frequency band, which is the half value of the Q-curve. In such a case, even if the specimen surface affects the probe, the oscillating cantilever easily damps and is slow to resonate, which would adversely affect. high resolution measurements. In the first operation, the probe comes into contact with the specimen surface, and the cantilever oscillating frequency is determined outside the frequency band, which is the half value of the Q-curve. As a result, the oscillating cantilever can be easily damped, so that uneven surface state data can be accurately obtained. In the second operation, since the probe is not in contact with the specimen surface, the cantilever oscillating frequency is changed to the frequency near the resonance point. Therefore, the cantilever quickly resonates, which enables accurate measurement of the physical properties of the specimen surface. The physical properties of the specimen surfaces are a magnetic field, an electric field, physical action force and so on. For instance, a probe covered by a magnetic coat is subject to attraction and repulsion in accordance with a distribution of the magnetic force on the specimen surface during the second operation. The attraction or repulsion of the probe is detected as a phase difference. When phase signals are mapped with respect to an area to be measured, the scanning probe microscope can function as a magnetic force microscope, which can measure the magnetic field distribution of the specimen surface. Further, a probe covered by a conductive coat undergoes attraction due to the electrostatic conduction in accordance with a potential distribution on the specimen surface in the second operation. The larger the potential distribution on the specimen surface, the larger attraction the probe is subject to. The attraction of the probe is detected as a phase difference. When phase signals are mapped with respect to an area to be measured, the scanning probe microscope can function as a potential force microscope, which can measure a potential distribution on the specimen surface. Still further, a probe provided with a resin coat or a macromolecular ball is charged depending upon a material of the resin coat or macromolecular ball in accordance with a potential distribution on the specimen surface during the second operation. As a result, the probe is subject to the attraction and repulsion at different positions of the specimen surface. The probe measures the attraction or repulsion as a phase difference in accordance with a positive or negative potential on the specimen surface. When phase signals are mapped with respect to an area to be measured, the scanning probe microscope can function as a potential force microscope, which can measure a potential distribution on the specimen surface. During the second operation, physical interaction force (e.g. van der Waals force or the like) of the specimen surface and the probe, which are not in contact with each other, can be detected as a phase difference, regardless of the conductive or resin coat on the probe. When phase signals are mapped with respect to an area to be measured, the scanning probe microscope can function as a physical force microscope, which can measure a distribution of physical interaction force of the specimen surface without touching the probe. FIG. 7 shows how to obtain a frequency shift of the resonance point on the basis of phase signals, which are obtained by the procedure shown in FIG. 6. Further, a shift of a resonance frequency may be obtained on the basis of phase signals. When mapping the shift of the resonance frequency in the second operation, the scanning probe microscope can function as the magnetic, potential or physical action force microscope as described above. The cantilever may not be oscillated in the second operation. In such a case, the cantilever is subject to non-contact restraints (e.g. electrostatic force, magnetic force or the like) due to physical properties of the specimen surface, and the laser beam reflecting surface of the cantilever is flexed. Receiving the attraction from the specimen surface, the probe comes close to the specimen. Conversely, when receiving the repulsion from the specimen surface, the probe tends to move away from the specimen. Physical properties of the specimen surface can be measured by detecting the flexibility of the laser beam reflecting surface using an optical head. Both the first and second operations may be performed at respective points in an area to be measured. At a certain point, the second operation is carried out immediately after the first operation. At an adjacent point, the specimen and probe are relatively displaced, and the first and second operations are repeated as stated above. Uneven surface state data and physical property data of the specimen can be obtained by repeating the foregoing procedures. Further, the first and second operations may be performed at each line in an area to be measured. At a certain line, the first operation is carried out in order to measure the uneven surface state of the specimen, and the obtained data are stored. Thereafter, at the same line, the second operation is performed with the probe spaced from the specimen surface on the basis of the stored uneven surface state data. At an adjacent line, the probe and the specimen are relatively displaced, and the first and second operations are performed as above. Uneven surface state data and physical property data of the specimen can be obtained by repeating the foregoing procedures. The first and second operations may be performed for each frame in an area to be measured. First of all, the first operation is carried out for all of the frames. In this case, uneven surface state data are stored as two-dimensional data. Thereafter, the second operation is conducted with the probe spaced by a certain extent from the specimen on the basis of the stored two-dimensional data. Further, the first operation may be performed for a frame of an area to be measured, thereby obtaining uneven surface state data. Thereafter, the probe is moved by the specimen moving means to the next point to be measured. The second operation may be performed at only this point in order to obtain physical property data of the specimen. During the second operation, either a magnetic or electric field may be applied to the specimen. By varying the intensity of the magnetic or electric field, it is possible to measure variations of physical property data of the specimen surface, which are obtained in the second operation. FIG. 8 shows an example in which a measurement is performed in a vacuum. Laser beams 5 from a laser 61 are introduced into a vacuum container 63 via a window 62. Both the window 62 and the vacuum container 63 are airtight, and the vacuum container 63 is completely made void by a vacuum pump means 64. The vacuum container 63 houses a specimen stand 65, on which a cantilever 2, cantilever oscillating means 3 and specimen 9 are placed in a heated or cooled state, or at a room temperature. The specimen stand 65 is laterally and vertically moved by a specimen stand moving means 69. Laser beams are introduced into the vacuum container via the window, and are radiated onto the laser beam-reflecting surface of the cantilever 2. Reflected laser beams 7 reach, via the window, the optical position sensor 8, which is positioned outside the vacuum container 8. The amplitude of the cantilever is measured on the basis of the position of the reflected laser beam on the optical position sensor. In the first operation, when the probe comes into contact with the specimen surface, the amplitude of the cantilever is reduced. The cantilever is moved up and down in order to maintain the reduced amplitude in accordance with the scanning operation of the specimen moving means, so that uneven surface state data of the specimen can be obtained. In this case, the cantilever oscillating frequency is determined to be outside the frequency band having the half value of the Q-curve. Therefore, the cantilever can be easily damped and follow the uneven surface shape of the specimen, thereby obtaining uneven surface state data of the specimen. In the second operation, when a waveform of a voltage applied to the cantilever oscillating means 3 and an output signal of the optical position sensor 8 are measured, a time delay (phase) of the probe leaving the specimen can be measured. Since the time delay depends upon physical property values of the specimen surface, it is possible to measure a distribution of the physical properties. The foregoing measurements can be conducted not only in the vacuum but also in the vacuum container, which is made void by the vacuum pump means and is then filled with a gas 68 to ambient air pressure. In this case, a moist gas may be introduced into the vacuum chamber. Further, a dry or moist gas may be continuously introduced into the vacuum chamber without making it void, and measurements may be performed at ambient air pressure 1. The specimen may be put in a cell containing a solution, and is placed on the specimen moving means in order to perform measurements in the solution. Measurements can be performed by applying a magnetic or electric field to the specimen perpendicularly, laterally or at a desired angle. Means for applying the magnetic or electric field may be positioned near the specimen, or outside the vacuum container. When applying the magnetic field, a coil may be placed near the specimen. The intensity of the magnetic field may be varied by applying varying currents to the coil. Further, the intensity of the magnetic field may be varied by changing the distance between the coil and the specimen using a permanent magnet. Next, when applying the electric field, a coil is placed near the specimen. Intensity of the electric field can be changed by applying varying currents to the coil. Further, an electrode plate may be placed near the specimen, and intensity of the electric field may be changed by applying varying currents to the electrode plate. In the first operation, the cantilever oscillating frequency is determined to be outside the frequency band having the half value of the Q-curve of the amplitude and oscillation frequency of the cantilever. This is effective in damping the cantilever with ease, and enabling the probe to follow the uneven surface of specimen not only in the air but also in the vacuum, gas or solution. Therefore, the uneven surface state data can be accurately obtained. Further, in the second operation, the probe can be spaced from the specimen on the basis of the uneven surface state data, so that physical property data of the specimen can be obtained with tie probe spaced therefrom. The present invention described above is advantageous in the following respects. The scanning probe microscope comprises a cantilever having a minute probe at one end thereof, a laser radiating laser beams to a laser beam reflecting surface of the cantilever, an optical position sensor detecting positions of reflected laser beams, specimen moving means moving a specimen, and cantilever oscillating means periodically oscillating the cantilever with a predetermined amplitude. The scanning probe microscope performs: a first operation in which if the optical position sensor detects a reduced amplitude when the probe of the cantilever comes into contact with the specimen, uneven surface state data of the specimen are obtained on the basis of a control amount of upward and downward movements of the specimen moving means which is moved upward or downward in order to maintain the reduced amplitude constant, and a second operation in which physical operation data of the specimen are obtained by keeping the probe spaced by a predetermined extent from the specimen on the basis of the uneven surface state data obtained by the first operation. In the first operation, the uneven surface state data are obtained by oscillating the cantilever with an oscillation frequency outside the frequency band, which is half of a value of a dependent curve (Q-curve) of a cantilever oscillating frequency and amplitude. This arrangement enables the cantilever to damp with ease, and assures accurate measurements of uneven surface state data. In the second operation, the probe is spaced from the specimen with a predetermined extent on the basis of the uneven surface state data obtained in the first operation, which enables physical property data of the specimen surface to be accurately obtained.
	summary
	description	This invention was made with Government support under Contract No. DE-NE0000583 awarded by the Department of Energy. The Government has certain rights in this invention. The following pertains to the nuclear reactor safety arts, nuclear power arts, and related arts. A nuclear reactor includes a radioactive core comprising a fissile material immersed in coolant. In a light water reactor, the fissile material is typically a uranium composition such as uranium oxide (UO2) enriched in the fissile 235U isotope, and the coolant is purified water. The nuclear reactor core and the immersing coolant are contained in a reactor pressure vessel. A coolant flow circuit may be provided via large diameter piping, e.g. between the reactor pressure vessel and an external steam generator, or between the reactor pressure vessel and a turbine. For example, in a typical boiling water reactor (BWR), a coolant circuit is provided to transfer coolant in the form of steam to drive a turbine to generate electricity. In a typical pressurized water reactor (PWR), a coolant circuit is provided to transfer coolant to a steam generator. In integral PWR Designs, the steam generator is located inside the reactor pressure vessel, so that there is no external coolant loop implicating large diameter piping. In a loss of coolant accident (LOCA), there is a radiological release outside of the reactor pressure vessel as escaping coolant flashes to steam. To prevent radiological release to the environment, the reactor pressure vessel is contained in a radiological containment (sometimes shortened to “containment”). A PWR with its external steam generator is located inside a radiological containment in the form of a steel or steel-reinforced concrete structure. This radiological containment is located in a compartment of a surrounding reactor building that services the nuclear reactor and ancillary components (sometimes also called a reactor service building). In PWR designs, the steam generator (whether external from the reactor pressure vessel or integrally located as in integral PWR designs) also receives secondary coolant that is kept separate from the (primary) coolant that flows through the reactor pressure vessel. This secondary coolant is therefore not contaminated with radiological contaminants, and may be piped outside containment through suitable safety valving. A typical BWR nuclear island is designed similarly to a PWR. However, in a BWR coolant in the form of steam is piped directly into the turbine, which is located outside containment. (By contrast, in a PWR secondary coolant converted to steam and drives the turbine). This steam contains radiological contaminants. Accordingly, in some BWR systems a secondary containment is provided which surrounds the (primary) radiological containment and the turbine. The secondary containment is active, i.e. maintained at a negative pressure using active blowers to pull air through filters to the outside environment. Some primary containment designs have leakage rates as low as 0.1% of containment volume per day, providing a decontamination factor over the first 24 hours after a radiological release of approximately 1000. A secondary containment can improve upon this, but requires AC power to operate the blowers and other active components. Secondary containment is difficult to employ in a passive nuclear power plant because safety-related AC power is not available. Even where safety-related AC power is available, it can be lost due to weather-related events or the like. In some embodiments described herein as illustrative examples, a nuclear reactor system comprises: a nuclear reactor including a reactor core comprising fissile material disposed in a reactor pressure vessel; a radiological containment containing the nuclear reactor; a containment compartment containing the radiological containment; a heat sink comprising a chimney configured to develop an upward flowing draft in response to heated fluid flowing into a lower portion of the chimney; and a fluid conduit arranged to receive fluid from the containment compartment and to discharge into the chimney. The nuclear reactor system may further comprise a filter, with the fluid conduit including a first fluid conduit arranged to receive fluid from the containment compartment and to discharge into an inlet of the filter, and a second fluid conduit arranged to receive fluid from an outlet of the filter and to discharge into the chimney. The filter may comprise at least one of a charcoal filter and a zeolite filter. The heat sink may further include a body of water in thermal communication with the radiological containment to transfer heat from the radiological containment into the body of water, and a heat sink conduit arranged to receive water vapor or steam from the body of water and to discharge the water vapor or steam into the lower portion of the chimney. In some embodiments there is no blower or pump configured to move fluid through the fluid conduit. In some embodiments described herein as illustrative examples, a method is disclosed, which operates in conjunction with a nuclear reactor including a reactor core comprising fissile material disposed in a reactor pressure vessel, and a radiological containment containing the nuclear reactor, and a containment compartment containing the radiological containment. The method comprises: generating a draft in a chimney; and using the draft to draw air from the containment compartment into the chimney. The method may further comprise, before the air reaches the chimney, filtering the air drawn from the containment compartment using a filter effective to remove radioactive particles from the air. Additionally or alternatively, the method may further comprise, after the air is drawn into the chimney, filtering the air using a filter disposed in the chimney. The operation of using the draft to draw air from the containment compartment into the chimney may suitably comprise providing a fluid conduit connecting the containment compartment with the chimney wherein the fluid conduit connects with the chimney at an elevation effective for the draft to draw air from the fluid conduit into the chimney. The method may further comprise responding to a reactor loss of coolant accident (LOCA) wherein one or both of the LOCA and the responding discharges coolant from the nuclear reactor into the radiological containment whereby both heat and radioactive particles are transferred from the nuclear reactor into the radiological containment. In such embodiments the method may further comprise leaking radioactive particles from the radiological containment into the containment compartment at a leakage rate of the radiological containment, and filtering air drawn using the draft from the containment compartment into the chimney using a filter effective to filter out radioactive particles leaked into the containment compartment. In some embodiments described herein as illustrative examples, a system is disclosed, which is operative operative in conjunction with a nuclear reactor including a reactor core comprising fissile material disposed in a reactor pressure vessel, and a radiological containment containing the nuclear reactor. The system comprises: a containment compartment containing the radiological containment; a heat sink comprising a chimney; and a fluid conduit connecting the containment compartment with the chimney. The fluid conduit may include a filter configured to filter radioactive particles emitted by the nuclear reactor in a LOCA. With reference to FIG. 1, a nuclear reactor system includes a nuclear reactor 10 comprising a nuclear reactor core 12 disposed in a reactor pressure vessel 14. It is to be understood that the reactor pressure vessel 14, which is typically a stainless steel or other metal vessel, is opaque such that the nuclear reactor core 12 is occluded by the reactor pressure vessel 14; accordingly, FIG. 1 shows the reactor core 12 diagrammatically in phantom, i.e. using dashed lines, to indicate it is actually hidden from view being disposed inside the reactor pressure vessel 14. During reactor operation, the reactor pressure vessel 14 contains coolant (sometimes referred to as “primary” coolant to distinguish, in the case of a PWR, from secondary coolant that flows through the steam generator). The nuclear reactor core 12 contains a fissile material. In the illustrative examples, the nuclear reactor is a light water reactor employing a uranium composition such as uranium oxide (UO2) enriched in the fissile 235U isotope, and the coolant is purified water. However, other reactors are contemplated, such as a sodium-cooled reactor. During reactor operation, the nuclear reactor core 12 supports a nuclear fission chain reaction involving the fissile material (e.g. 235U), and the nuclear fission chain reaction generates heat in the nuclear reactor core 12 that in turn heats the coolant in the reactor pressure vessel 14. The coolant serves (at least) two purposes: (1) providing cooling of the nuclear reactor core 12, and (2) providing a heat transfer medium to transfer heat from the nuclear reactor core 12 to another component, such as a steam generator (in the case of a typical PWR-based nuclear power plant) or a turbine (in the case of a typical BWR-based plant). The illustrative nuclear reactor 12 is an integral PWR design in which the steam generators are located inside the reactor pressure vessel 14 (and hence are not visible). In other PWR designs (not shown) the steam generators are external units connected with the nuclear reactor by large-diameter piping. BWR designs (also not shown) typically omit the steam generator component because the (primary) coolant boils inside the reactor pressure vessel, and the boiling primary coolant directly serves as steam to drive the turbine via suitable large-diameter piping running between the BWR and the turbine. The nuclear reactor is disposed inside a radiological containment 16, which is typically a steel or steel-reinforced concrete structure. The illustrative radiological containment 16 is a steel cylindrical structure with top and bottom domes; however, other geometries, e.g. rectangular geometries, are contemplated. The lower dome of the illustrative radiological containment 16 is shown in dashed line, and is embedded in the concrete floor of a containment compartment 20 that contains the radiological containment 16. The illustrative containment compartment 20 is part of a reactor building 22 (shown in part in FIG. 1) that services the nuclear reactor and ancillary components. The reactor building 22 is also referred to in the art by other nomenclatures, such as “reactor service building”. The illustrative reactor building 22 is partially subterranean (where ground level is diagrammatically indicated by ground G), and the illustrative containment compartment 20 is wholly underground. However, it is contemplated for the containment compartment to be only partially underground or even above-ground. The illustrative reactor building 22 includes an above-ground portion 24 located above the containment compartment 20. The above-ground portion 24 may, for example, serve as a garage, warehouse, or the like where trucks delivering nuclear fuel or other components can be received. While the illustrative containment compartment 20 is part of the illustrative reactor building 22, more generally the containment compartment is a compartment that contains the radiological containment and that is configured for passive removal and optional filtering of air in the compartment using techniques as disclosed herein. The radiological containment 16 is designed to contain radiation that escapes from the nuclear reactor in the event of a loss of coolant accident (LOCA). A LOCA arises when there is a break in the reactor pressure vessel 14, or in a large-diameter pipe connecting with the reactor pressure vessel 14, such that (primary) coolant in the nuclear reactor enters into the radiological containment 16. This usually occurs, at least initially, in the form of steam or a two-phase mixture as escaping coolant flashes to steam due to rapid pressure drop. Depending upon the nature and extent of the LOCA break, the remedial response performed by automatic systems and/or by actions of reactor operators may include depressurizing the reactor pressure vessel 14 by intentionally venting coolant from the nuclear reactor into the radiological containment 16, or keeping the reactor under (possibly reduced) pressure while monitoring reactor conditions and closing the LOCA break, e.g. using suitable valves. In either case, the nuclear reactor core 12 should be kept immersed in coolant, and to this end additional coolant may be injected into the pressure vessel 14 from an intermediate pressure injection tank (IPIT), a refueling water storage tank (RWST), reactor coolant system inventory/purification (RCSIP) system, or other coolant source (components not shown). Generally, one or both of the LOCA itself and the response to the LOCA (e.g. venting to depressurize the reactor pressure vessel 14) discharges coolant from the nuclear reactor into the radiological containment, and this discharge transfers both heat and radioactive particles from the nuclear reactor into the radiological containment 16. Heat transferred into the radiological containment 16 during a LOCA is removed by cooling systems to a heat sink located outside of the radiological containment 16. Additionally, while the nuclear chain reaction is shut down during a LOCA, residual decay heat continues to be generated in the reactor core 12 due to radioactive decay of intermediate fission products. This heat is transferred to a heat sink located outside containment, by a system typically referred to as an emergency core cooling (ECC) system. The heat sink that receives and dissipates the decay heat is typically referred to as the ultimate heat sink (UHS). Heat released into the radiological containment 16 may be rejected to the same UHS that dissipates core residual decay heat, or to a different heat sink. In the illustrative embodiment of FIG. 1, the heat sink for the radiological containment 16 includes a passive containment cooling tank (PCCT) 26 located on the top dome of the radiological containment 16 serves as the heat sink for the radiological containment 16, and optionally may also serve as the UHS. The illustrative PCCT 16 is a covered body of water located inside the containment compartment 20 and disposed on top of the radiological containment 16. Heat released into the radiological containment 16 transfers to the PCCT 26 by thermal communication through the top dome of the radiological containment 16. Some illustrative examples of suitable heat sinks are described, by way of illustrative example, in Watson et al., U.S. Pub. No. 2013/0051511 and Bingham, U.S. Pub. No. 2013/0156143, both of which are incorporated herein by reference in their entireties. The heat sink for the radiological containment 16 further includes a chimney 30 that is configured to develop an upward-flowing draft in response to heated fluid flowing into a lower portion of the chimney 30. A heat sink conduit 32 is arranged to receive water vapor or steam from the PCCT 26 and to discharge the water vapor or steam into the lower portion of the chimney 30. During a LOCA, heat in radiological containment 16 transfers through the top dome to the PCCT 26, where the heat raises the temperature of the water in the PCCT 26 to produce enhanced evaporation (yielding water vapor) or boiling (yielding steam) that passes through the heat sink conduit 32 and into the lower portion of the chimney 30, so as to develop an upward-flowing draft in the chimney 30 that passively pulls water vapor or steam (and its contained heat energy) through the chimney 30 to discharge at the top of the chimney 30 so as to release the heat to the environment. This passive cooling mechanism provided by the chimney 30 advantageously can continue to operate even if nuclear plant emergency electrical power is lost, as it is the heating of the radiological containment 16 due to the LOCA that develops and maintains the draft in the chimney 30. The heat sink including the PCCT 26 and chimney 30 provides for removal of heat released into the radiological containment 16 during a LOCA. This pathway does not remove radiological contamination, which is advantageously trapped inside the radiological containment 16. However, in practice the radiological containment 16 has a leakage rate, which is preferably small. In some radiological containment designs, the leakage rate is 0.1% of containment volume per day or lower, providing a decontamination factor over the first 24 hours after a LOCA of approximately 1000. Even this small leakage of radiation from the radiological containment 16 into the surrounding containment compartment 20 is not removed via the heat sink including the PCCT 26 and chimney 30. Although the illustrative PCCT 26 is located inside the containment compartment 20, it is a covered body of water, which blocks ingress of radiation contamination from the containment compartment 20 into the PCCT 26. In other embodiments, the body of water may be located outside of the containment compartment, with (by way of illustrative example) a heat exchanger providing thermal communication between the body of water and the radiological containment. The containment compartment 20 is not designed to be well-sealed. Accordingly, radioactive contaminants leaking from the radiological containment 16 into the containment compartment 20 are expected to escape into the surrounding ambient (e.g. at gaps between walls, at door gaps, building air ventilation, or so forth). During a LOCA it is advantageous for nuclear power plant operators to remain on-site, and more particularly inside the reactor building 22, in order to carry out remedial procedures in response to the LOCA. If radiation levels in the reactor building 22 (which includes the containment compartment 20) become too high, plant operators must be evacuated, which complicates and may delay the LOCA response. Accordingly, it is advantageous to remove radioactive contaminents from the containment compartment 20. This can be done using active filtration systems driven by electrically powered blowers. However, these systems rely upon availability of safety-related AC power, which may be unavailable in nuclear plants designed to employ passive safety systems. Even if safety-related AC power is available, it can be lost due to weather-related events or the like. With continuing reference to FIG. 1, an improved approach disclosed herein relies upon providing the chimney 30 as part of the heat sink for the radiological containment 16 (and/or for removal of reactor core decay heat via the ECC system), and leverages this chimney 30 to also provide motive power to operate the containment compartment radioactive contaminants filtration system. To this end, a fluid conduit 40, 42 is arranged to receive fluid from the containment compartment 20 and to discharge into the chimney 30. Optionally, the fluid conduit includes a filter 44 configured to filter radioactive particles emitted by the nuclear reactor in a LOCA. In the illustrative example, the fluid conduit 40, 42 includes a first fluid conduit 40 arranged to receive fluid from the containment compartment 20 and to discharge into an inlet of the filter 44, and a second fluid conduit 42 arranged to receive fluid from an outlet of the filter 44 and to discharge into the chimney 30. In this approach, the filtering of the air is performed before the air reaches the chimney 30. Additionally or alternatively, a filter 46 may be provided in the chimney 30, at a point higher in elevation than the point at which the fluid conduit 42 discharges into the chimney 30. In this approach, the air from the containment compartment 20 is filtered after the air is drawn into the chimney 30. A disadvantage of the filter 46 is that it may impede development of the draft in the chimney 30. In some embodiments both filters 44, 46 are provided, and optionally may be filters of different types. On the other hand, in yet another variant embodiment it is contemplated to omit both filters 44, 46, so that no filtering of the air is performed. This approach (i.e. omitting filtration entirely) still provides the benefit of passively drawing air from the containment compartment 20 so as to remove radioactive particles. Although such radioactive particles would eventually escape via various gaps in the reactor building 22 and/or via existing building ventilation systems (assuming they have motive electrical power during the LOCA), these egress pathways are relatively slow and result in discharge of radioactive contaminants at close to ground level, potentially leading to high radiation levels on the premises. By employing the chimney 30 and conduit 42, 44, the radioactive contaminants are drawn out of the containment compartment 20 and discharged at a high elevation H corresponding to the height of the chimney 30. This disperses and dilutes the radiation over a large area, reducing individual radiation doses. The filter 44, 46 is configured to filter radioactive particles based on the nature of the particles to be filtered. Some suitable filters include activated charcoal filters, zeolite filters, or combinations thereof; preferable configured to minimize pressure drop across the filters. The filtration system 40, 42, 44, 46 is integrated with the heat sink 26, 30 comprising the chimney 30 which is used to heat-sink the radiological containment 26 (as shown in FIG. 1) and/or decay heat from the reactor core 12. This integration ensures that the chimney 30 will have a developed draft during any LOCA, which ensures the draft is available for passively driving filtration of the containment compartment 20 during any LOCA event, even if emergency power is lost. Advantageously, there is no need for a blower or pump configured to move fluid through the fluid conduit, as the draft in the chimney 30 provides the motive force. The temperature in the containment compartment 20 may be elevated due to heat transfer from the radiological containment 16, and may be up to 200° F. or higher in some LOCA scenarios. Air from the containment compartment 20 provided via the fluid conduit 42, 44 may or may not be sufficient, by itself, to develop a draft in the chimney 30. During a LOCA the draft in the chimney 30 is developed and/or reinforced by the (heated) water vapor or steam evolving from the PCCT 26 and discharging via the heat sink conduit 32 into the lower portion of the chimney 30. In general, the draft drives (i.e. pulls) air from the containment compartment 20 into the chimney 30 via the fluid conduit 42, 44. If the draft due to the PCCT 26 (and/or due to the ECC system, if it rejects heat into the chimney 30) is substantially stronger than the draft due to the containment compartment 20, then it may be advantageous for the fluid conduit 44 to be arranged to discharge into the chimney 30 at an elevation that is higher than the elevation at which the heat sink conduit 32 (and/or ECC system) discharges into the chimney 30. With reference to FIG. 2, another illustrative embodiment is shown, which again operates in conjunction with the nuclear reactor 12, 14 disposed in the radiological containment 16 which in turn is surrounded by the containment compartment 20, which in illustrative FIG. 2 is again part of the reactor service building 22 which further includes an above-ground portion 24. However, the illustrative embodiment of FIG. 2 employs a different heat sink. In the embodiment of FIG. 2 the PCCT 26 and the chimney 30 are omitted, and in their place is provided a cooling tower 50, which in the illustrative example is a hyperboloid cooling tower 50 that develops a natural draft. Hence, the cooling tower 50 is a type of chimney. A body of water (not shown) may be located at the bottom of the cooling tower 50, or may be located elsewhere and connected with the cooling tower 50 by suitable conduits. The heat sink including the cooling tower 50 may receive heat from the radiological containment 26, for example via a set of heat exchangers, and/or may receive heat from the ECC system operating to remove decay heat from the reactor core 12. In the context of the system of FIG. 2, the passive containment compartment filtration system is modified as follows. The first conduit 40 and the filter 44 are retained; however, the second conduit 42 is replaced by a longer second conduit 52 that runs underground (as shown) or above ground to the cooling tower 50. To provide discharge at an elevated position located well within the draft, the illustrative second conduit 42 an optional vertical standpipe portion 53 located inside the cooling tower 50. Operation is analogous to that described with reference to FIG. 1—the draft developed and maintained in the cooling tower 50 during a LOCA (and perhaps at other times) serves to draw air from the containment compartment 20 through the first conduit 42 into the inlet of the filter 44, through the filter 44, and thence through the second conduit 52, 53 into the cooling tower 50 (which serves as the chimney). The illustrative embodiments are merely examples. The disclosed passive containment compartment cooling systems are readily employed in combination with other nuclear reactor designs, including PWR designs (both integral and employing external steam generators), BWR designs, and so forth. While an illustrative subterranean nuclear reactor is shown, the nuclear reactor may instead be above-ground, with suitable adjustment of the height H of the chimney. In general, the height of the chimney is chosen to provide the desired heat sinking, and also to provide sufficient draft for operation of the passive containment compartment cooling system. In most cases, it is expected that a height sufficient to provide the heat sinking functionality will also be sufficient for the passive containment compartment cooling system. Illustrative embodiments including the preferred embodiments have been described. While specific embodiments have been shown and described in detail to illustrate the application and principles of the invention and methods, it will be understood that it is not intended that the present invention be limited thereto and that the invention may be embodied otherwise without departing from such principles. In some embodiments of the invention, certain features of the invention may sometimes be used to advantage without a corresponding use of the other features. Accordingly, all such changes and embodiments properly fall within the scope of the following claims. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the present disclosure be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
	summary
	claims	1. A method of forming a permanent depository in a borehole for highly radioactive material, the method comprising the steps of:forming in the borehole by metal fusion drilling a metal lining from a casting continuously formed from a metal melt and thereby forming the wall thickness of the metal lining of a lower borehole region such that the wall thickness increases from the top downward and a downward widening of the lower region;depositing the highly radioactive material for final storage in the lower region of the lined borehole; andmelting this lining locally immediately above this lower area after deposition of the material to separate the lower region holding the material from the rest of the lining and permit this lower region and the material held therein to migrate automatically downward toward the center of the earth, whereby the downward widening of the lower region converts lateral compressive forces on the lower region into a vertical downward thrust force that force the separated lower region downward into the earth. 2. The method according to claim 1 wherein the migration is supported by residual heat-generation of the highly radioactive material. 3. The method according to claim 1 wherein the borehole is sunk to such a depth that the rock pressure or the permanent weight under the force of gravity and or a rock melt formation from the hot deep-seated rock supports the migration. 4. The method according to claim 1 wherein the borehole for final storage is produced by self-driving directly in situ at a nuclear-power plant or an intermediate storage facility or other nuclear facilities. 5. The method according to claim 1, further comprising the step of:filling a medium into free spaces between the stored material as heat transfer media or as moderator for fast neutrons to increase heat dissipation. 6. The method according to claim 1, further comprising the step of:closing the filled lower borehole region by a pressure-resistant cover. 7. The method according to claim 6 wherein above the closed lower borehole region the cast-metal lining of the borehole is melted by a heat source on a magnetic slide melting apparatus and the lower borehole region is thus separated from the rest of the shaft, wherein the metal melt accruing during melting of the lining forms a pressure resistant plug atop the lower borehole region. 8. The method according to claim 1 wherein a partial melt formation occurring between the surrounding rock and the lining of the lower borehole region by residual heat production, autogenously generated heat of the deep-seated rock, lateral pressure of the rock, and the force of gravity on the separated lower borehole zone acts as a slide path between the hot deep-seated rock and the jacket of the final depository region and under lateral pressure of the rock or the effect of gravity on the separated lower borehole region accelerates downward migration of the separated lower region. 9. The method according to claim 8 wherein fluids dissolved in the partial melt formation follow or precede the hot lower borehole region in the migration into hotter regions of the earth's interior, whereby the safe disposal of the fluids pumped in is ensured and the migration is additionally accelerated. 10. The method according to claim 1, further comprising the steps of:providing the upper portion of the borehole with a shaft plug of metal melt andthereafter filling a further lower borehole region. 11. The method according to claim 1 wherein not only the final storage of the highly radioactive inventory of a nuclear-power plant, but also the dismantling thereof with direct final storage of the accruing material is carried out in situ in one and the same borehole, such that a connection from a reactor building or reactor, or intermediate storage facility to the borehole is produced. 12. The method according to claim 1 wherein the radioactive material is deposited in the lower region of the lined borehole with a magnetic slide device. 13. The method according to claim 1 wherein a tunnel runs from a reactor to a low-lying basin lined with graphite ingot molds with overflow crucibles and lying in decay area of the reactor or of an intermediate storage facility, so that the highly radioactive melt runs into the basin, the reactor melt being directly deposited via an automated transport system into a lower borehole region as final depository.
	description	This application claims priority to U.S. Provisional Application No. 60/894,593, filed on March 13, 2007. The entirety of US Provisional Application No. 60/894,593 is incorporated herein by reference. This invention was made with government support under grant no. ECS-0404308 awarded by the National Science Foundation. The government has certain rights in the invention. 1. Field of the Invention The present invention relates to a method for manufacturing a particulate filter comprising a membrane with a high density array of regularly spaced micropores and a macroporous support. 2. Description of the Background Art A lithographic apparatus or device is a machine that applies a desired pattern onto a substrate, usually onto a target portion of the substrate, such as a membrane substrate. A lithographic device can be used, for example, in the manufacture of integrated circuits (ICs). In that instance, a patterning device, which is alternatively referred to as a mask or a reticle, may be used to generate a circuit pattern to be formed on an individual layer of the IC. This pattern can be transferred onto a target portion (e.g. comprising part of, one, or several dies) on a substrate (e.g. a silicon wafer). Transfer of the pattern is typically via imaging onto a layer of radiation-sensitive material (resist) provided on the substrate. In general, a single substrate will contain a network of adjacent target portions that are successively patterned. Known lithographic apparatus include so-called steppers, in which each target portion is irradiated by exposing an entire pattern onto the target portion at one time, and so-called scanners, in which each target portion is irradiated by scanning the pattern through a radiation beam in a given direction (the “scanning”-direction) while synchronously scanning the substrate parallel or anti-parallel to this direction. It is also possible to transfer the pattern from the patterning device to the substrate by imprinting the pattern onto the substrate. The formation of membrane filters with small straight-through holes of extremely small diameter and methods of making such porous bodies and/or microporous membranes are well known. Microporous membranes can be produced with particles which produce chains of defects in the glass, crystal or polymer membrane corresponding to the path of the particles. These defects make the areas around them very sensitive to various chemical agents. An exposure of relatively short duration to these agents makes it possible to produce pores at various locations. A longer exposure makes it possible to expand the number of pores. Accordingly, in various prior art processes the duration of chemical attack or etching facilitates control of the diameter of the pores produced, i.e. the filtration characteristic of the filter. Various methods including combinations of irradiation damage along substantially straight paths and chemical removal of the damaged material to provide pores or holes; bombarding a solid with heavy energetic particles to produce tracks of radiation damaged material which are removed by etching; forming ionization tracks in a membrane and removing by exposure to a suitable etchant solution; two-step etching processes that permits widening of the ion tracks to make a range of larger pore sizes; and/or the like. Typically the pores have been constructed to have a conical shape so as to assist back flushing. Often, however, filters constructed as disclosed have suffered from a high or higher specific flow resistance per unit area compared to other filter technologies. As a result, larger areas and/or higher differential pressures are required to achieve a particular filtrate flow than for low resistance filters. One solution for this issue has been the use of a macroporous support for a microporous filter membrane to enable thinner filter membranes to withstand the same filtration pressure. It has been observed that flow resistance is reduced in proportion to the reduction in thickness. Likewise, Keping Han, Wendong Xu, Ariel Ruiz, Paul Ruchhoeft, and Shankar Chellam, “Fabrication and Characterization of Polymeric Microfiltration Membranes using Aperture Array Lithography,” Journal of Membrane Science, Vol. 249 Issues 1-2, pages 193-206 (2005) discloses the use of a regular array of etched pores to form a filter membrane. This enables higher pore densities than are possible by the random array formed by ionization tracks because it eliminates the possibility of overlapping pores which compromise the selectivity of the filter. The flow resistance is reduced in inverse proportion to the increase in pore density. Primarily, the filters with a support have been formed on a flat solid substrate, thereby having at least the additional material cost of the flat substrates, multiple fabrication process steps, with the attendant inherent variation, and the fabrication of a large area of membranes by splicing or tiling together a multitude of small discrete membranes. Accordingly, it would be beneficial to the art field of producing filter membranes to accomplish at least one of minimizing process variation through producing the filter membranes in a continuous process; producing filter membranes with increased and/or enhanced pore density; producing filter membranes without the necessity of a solid support; and/or the like. Various embodiments of the present invention generally relate to lithographic exposure devices for fabricating a microporous filter membrane comprising means for exposing a membrane substrate to a beam comprising at least one energetic particle; means for conveying said membrane substrate; and, a mask positioned between said membrane substrate and at least one source of said at least one energetic particle, said beam comprising at least one particle transmitted through said mask. Further embodiments comprise a lithographic exposure device for fabricating a microporous filter membrane comprising a radiation source directed at least partially on a membrane substrate, wherein radiation emitted from said radiation source comprises a beam of at least one energetic particle; a device for conveying said membrane substrate comprising at least one supply reel and at least one take-up reel; and, a mask positioned between said membrane substrate and at least one source of said at least one energetic particle, said beam comprising at least one particle transmitted through said mask. Further embodiments comprise a filter membrane produced with the device according to a process and/with a device as herein disclosed. Further embodiments comprise a process for fabricating a membrane filter comprising the steps of conveying a membrane substrate in a stepwise fashion adjacent a mask; damaging said membrane substrate with at least one beam comprising at least one energetic particle emitted from at least one radiation source directed at least partially through said mask; and, removing said damaged membrane substrate with an etchant. Still further embodiments comprise a process for fabricating a microporous membrane filter, said process comprising the steps of applying an intermediate mask layer and a resist coating to a membrane substrate; conveying said membrane substrate in a stepwise fashion adjacent a mask; exposing said resist coating with at least one beam comprising at least one energetic particle emitted from at least one radiation source directed at least partially through said mask; developing said resist coating; etching said resists' pattern through said intermediate mask layer; and, etching said intermediate mask layer's pattern into said membrane substrate. A greater understanding of the present invention may be had from reference to the following detailed description and the appended claims. The particulars shown herein are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of various embodiments of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for the fundamental understanding of the invention, the description taken with the drawings and/or examples making apparent to those skilled in the art how the several forms of the invention may be embodied in practice. The following definitions and explanations are meant and intended to be controlling in any future construction unless clearly and unambiguously modified in the following Examples or when application of the meaning renders any construction meaningless or essentially meaningless. In cases where the construction of the term would render it meaningless or essentially meaningless, the definition should be taken from Webster's Dictionary, 3rd Edition. As used herein, all percentages are percentages by weight, unless stated otherwise. As used herein, the term “radiation” means and refers to energy radiated or transmitted as rays, waves, in the form of particles. In general, various embodiments of the present invention provides processes and systems for manufacturing large area or enhanced area filter membranes from polymeric sheet stock. Further, various embodiments of the present invention relate to the as produced filter membranes. Embodiments of processes, systems and filters of the present invention generally provide for at least one of minimized process variation and cost through producing the filter membranes in a continuous process; producing filter membranes with increased and/or enhanced pore density without pore overlap; producing filter membranes without the necessity of a solid support; producing large area filters without the necessity of splicing or tiling small discrete filters together, and/or the like. In various embodiments, energetic particles are used to damage a polymeric membrane substrate and a suitable etchant, such as, but not limited to a hot solution of KOH, is used to remove the damaged substrate material. A substantially uniform array of holes is formed by energetic particle exposure through a mask. In an embodiment, the array of holes is uniform throughout the substrate material. Membrane substrates of the present invention can be produced supported or unsupported. In an embodiment, a membrane substrate is processed as a free-standing polymeric sheet. In an alternate embodiment, a macroporous backing is present on at least a portion of the substrate to enhance strength characteristics. In various embodiments, a membrane substrate is deposited by extrusion, casting, spin coating, vapor deposition, epitaxy, chemical vapor deposition, sputtering, and/or any other process common in the art. Typical thicknesses of a membrane substrate of the present invention in an embodiment are about 20 μm to about 500 nm. In an alternate embodiment, a thicknesses of a membrane substrate of the present invention is about 100 nm to about 5 μm. In an alternate embodiment, a thicknesses of a membrane substrate of the present invention is about 10 nm to about 10 μm. In an alternate embodiment, a thicknesses of a membrane substrate of the present invention is about 5 nm to about 15 μm. However, in general, various embodiments of the membranes of the present invention can be formed of any thickness. Deposition techniques are well understood in the art field, especially the semiconductor art field, and the production of substantially flat membrane substrate, void from any substantial protrusions or other irregularities, is readily obtainable. However, in applications where a substantially flat membrane substrate is not required, extrusion, casting, spraying, sol-gel plating, and/or the like is capable of use for forming the membrane substrate. In general, any technique known in the art can be used in various embodiments of the present invention. A membrane filter of various embodiments of the present invention is characterized in that said membrane comprises a substantially flat layer of substantially uniform thickness and in that the surface of said layer is substantially void of any protrusions or any other irregularities. Appropriate thickness and uniformity of a membrane are characteristics capable of optimization to resist high relative fluxes from a variety of processes. To enhance the flow rate the filter should present a resistance which is as low as possible and therefore, in a preferred embodiment of the invention, comprises a membrane whose thickness is smaller than the average pore size and whose pore density is larger than 1 million per square centimeter. In general, the characteristic of selectivity of a filter membrane is determined by its largest pore(s). Consequently it is desirable to have a pore size distribution which is as uniform as possible. In order to offer a large selectivity a specific embodiment of the filter according to the invention is characterized in that the pores consist of perforations with relatively smooth edges and in that the membrane features a relatively sharp, well defined pore size distribution within a standard deviation of less than about 5%, as mentioned previously. In an alternate embodiment the standard deviation is less than about 3%. In an alternate embodiment the standard deviation is less than about 1%. Other embodiments are compared such that size of a hole differs by no greater than 5% from the size of any other hole formed in the substrate. In an alternate embodiment, the size difference is less than about 3%. In an alternate embodiment, the size difference is less than about 1%. In an alternate embodiment, the size difference is less than about 0.5%. In general, a membrane is capable of better performance characteristics with uniformity of hole size. However, various embodiments are capable of producing a non-uniform hole size as needed for a particular process and/or membrane. Depending on the application for the membrane filter, the perforations in the membrane may be constructed so as to be cylindrical, tapering, and/or the like. Tapering embodiments are particularly useful in ‘back flush’ applications, clogged perforations are easily reopened by means of a counter pressure pulse. Suitable materials for the membrane filter of various embodiments of the present invention are preferentially of a polymeric material, such as, but not limited to polyurethane, polytetrafluoroethylene (TEFLON), polyamide, polyamide, polyvinyl, polymethylmethacrylate, polypropylene, polyolefin, polycarbonate, polyester, cellulose, polyformaldehyde and polysulfone. Further embodiments are capable of comprising a biocompatible coating, such as a heparin coating and/or the like. The support may be macroporous with a tortuous pore structure, a sintered ceramic material, a sintered metal powder or a polymeric tortuous membrane, as well as an initially dense material in which in a later stage openings are made, for example in a semiconductor wafer, a metal support or an inorganic disc. The total strength of a membrane substrate of the present invention may be increased by a number of relatively thin supporting bridges in the support underneath. In various embodiments utilizing a support, between the membrane layer and the support layer, an intermediate layer may be deposited for bonding enhancement and stress reduction. Bonding enhancement layers might be silicon dioxide and titanium dioxide depending upon the nature of the membrane and support materials. In various embodiments, the intermediate layer may moreover act as an etch stop layer. Generally, in forming holes within the membrane substrate, any source of energetic particles, such as, ions, photons, electrons, neutral energetic atoms, and/or molecules can be used, such as, but not limited to photons, He+, H+, suitable equivalents, and/or the like. A substantially parallel beam of energetic particles is directed so as to impinge on a substantially planar mask perforated by stencil openings. In an embodiment, the stencil contains a series of uniform evenly dispersed holes through the mask. In an alternate embodiment, the stencil openings have a particular shape or design. Portions of the energetic particles passing through the holes or stencil openings in the mask damage a membrane substrate positioned about the mask. In various embodiments, the membrane substrate is essentially planar. In an alternate embodiment, the membrane substrate is non-planar. After exposing the membrane substrate to the beam of energetic particles, the substrate may be washed in a suitable solvent to remove the damaged portions of the membrane substrate and thereby revealing the holes. Deformation of the membrane substrate during these steps is acceptable, under constraints of the present invention. In an alternate embodiment of the method of the invention a deposited masking layer, particularly of a material sensitive to energetic particle exposure, is employed as the auxiliary layer which is brought in the desired pattern by means of an energetic particle lithography technique. The masking layer will be in contact with the membrane layer and therefore enables the transfer of its pattern to the membrane layer with a very high degree of precision. In yet an alternate embodiment an intermediate masking layer may be employed. In various embodiments, a membrane filter of the present invention is bio-compatible. In an embodiment, a characteristic of a biocompatible membrane is that its surface is smooth, with a surface roughness less than the pore size will, thereby inhibiting sticking of particles or cells on the membrane and in the perforations. Accordingly, various embodiments of a biocompatible membrane of the present invention comprises a filter capable of use for cell-cell separation techniques and other medical and biomedical purposes. In an embodiment of the filter according to the invention, the support and the membrane are constituted from equivalent materials with the same or similar components, for example polycarbonate. A filter of this kind is applicable in a wide temperature range, with a good cohesion between the support and the membrane. Alternatively a membrane of the kind used in the filter according to various embodiments of the invention may itself very well act as a support for an ultrafiltration layer. Very thin ultrafiltration layers, typically with a thickness less than 200 nm, may be deposited in or over the perforations of the membrane to constitute an ultrafiltration filter. However, the thickness of the ultrafiltration layer can varied as is suitable for the particular process. In various embodiments, a film processed under an embodiment of the present invention is held essentially stationary while energetic particle exposure is performed. In an embodiment, an electrostatic clamp as shown in FIG. 5 is used to clamp a thin metal film deposited onto the membrane substrate, thereby holding the membrane substrate essentially stationary with respect to the clamp. In addition, for embodiments utilizing deposition on the membrane substrate, depending on the desired application, exemplary embodiments of the present process may utilize simultaneous or sequential deposition of multiple metals of controlled composition. Other exemplary embodiments may utilize small metal catalyst particles, such as nickel, to grow orderly arrays of precisely positioned carbon nanotubes, for example. The process may also allow for alternating between different gasses, ions, and/or precursors to form multilayer structures. As such, various embodiments of the present invention comprise a lithographic exposure device for fabricating a microporous filter membrane comprising means for exposing a membrane substrate to a beam comprising at least one energetic particle; means for conveying said membrane substrate; and, a mask positioned between said membrane substrate and at least one source of said at least one energetic particle, said beam comprising at least one ion transmitted through said mask. Further embodiments comprise a filter membrane comprising at least one pore with at least one about one micrometer pore. In various embodiments, the mask is substantially stationary. In various embodiments, a clamp is used to secure said membrane substrate. Any source of radiation can be used in various embodiments of the present invention. In an embodiment, a helium ion source is used for irradiation. In an embodiment, a hydrogen ion source is used for irradiation. However, in general, any radiation source can be used. A suitable energy level is an energy level sufficient to completely penetrate the membrane substrate. The energy may be adjusted to tailor the specific shape of the micropores in the membrane. In various embodiments, the energy is greater than 500 keV. In various alternate embodiments, the energy is greater than 300 keV. In various alternate embodiments, the energy is greater than 100 keV. In various alternate embodiments, the energy is greater than 50 keV. In various alternate embodiments, the energy is greater than 25 keV. In various alternate embodiments, the energy is greater than 10 keV. In general, any energy level can be used as is appropriate for the particular application. In various embodiments, a lithographic exposure device of an embodiment of the present invention comprises a system for conveying the membrane substrate in a stepwise fashion wherein said membrane substrate is advanced about a length of said mask for every step. After exposure, an etchant system, such as hot KOH solution or an organic solvent, is used to remove the damaged membrane substrate. Further embodiments comprise a process for fabricating a membrane filter, said process comprising the steps of conveying a membrane substrate in a stepwise fashion adjacent a mask; damaging said membrane substrate with at least one beam comprising at least one ion emitted from at least one radiation source focused at least partially through said mask; and, removing said damaged membrane substrate with an etchant. Further embodiments comprise application of a high emissivity coating to said filter membrane substrate prior to exposure. As such, various further embodiments comprise removal of the high emissivity coating from said filter membrane substrate after exposure. An example of a water soluble high emissivity coating is black tempera paint. Most other paints, particularly those incorporating titanium dioxide particles also have high emissivity and can be removed in suitable solvents. Silicones also have high emissivities. The choice of a removable high emissivity coatings depends upon the ability of the membrane to withstand the solvent used to remove the coating. For example, Teflon membranes can tolerate acetone and commercial paint stripping solvents whereas polyester membranes cannot. Further embodiments comprise a filter membrane produced according to the various methods and apparatuses herein disclosed. In various embodiments, more than one etching step is performed, such that the film is etched by more than one etchant. A surfactant is capable of being added to the pre-etchant or etchant to improve their wetting characteristics and to lower the cone angle, as is understood by one of ordinary skill in the art. Filters produced with various processes of the present invention are suitable for use in any process or apparatus wherein a separation at least partially based upon size is desired. As such, various embodiments find wide applicability for use in separating materials of a very small size, such as, for example and not by way of limitation, virus, cysts, bacteria and the like. Further industrial embodiments of various membranes produced with processes of the present invention comprise purification of drinking and waste water, pharmaceuticals, food, fuels, chemicals, gas separation ultra filtration filter(s), and/or the like. Various embodiments of the present invention comprise a process for fabricating a membrane filter, said process comprising the steps of conveying a membrane substrate in a stepwise fashion adjacent a mask; damaging said membrane substrate with at least one beam comprising at least one energetic particle emitted from at least one radiation source directed at least partially through said mask; and, removing said damaged membrane substrate with an etchant. Still further embodiments comprise a process for fabricating a microporous membrane filter, said process comprising the steps of applying an intermediate mask layer and a resist coating to a membrane substrate; conveying said membrane substrate in a stepwise fashion adjacent a mask; exposing said resist coating with at least one beam comprising at least one energetic particle emitted from at least one radiation source directed at least partially through said mask; developing said resist coating; etching said resists' pattern through said intermediate mask layer; and, etching said intermediate mask layer's pattern into said membrane substrate. The invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. For example, ceramic materials are expected to function as membrane substrates. However, as the invention contemplates a reel to reel fabrication process, these embodiments were not mentioned, but would be acceptable. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. All changes to the claims which come within the meaning and range of equivalency of the claims are to be embraced within their scope. Further, all published documents, patents, and applications mentioned herein are hereby incorporated by reference, as if presented in their entirety. FIG. 1 is an illustration of beam (3) of energetic particles impinges on a substantially planar mask (2) perforated by stencil openings (4). A structured beam of transmitted beamlets (5) damages the non-planar membrane substrate (1) in a highly uniform array of regularly spaced regions. FIG. 1 illustrates the exposure process in which a substantially parallel beam (3) of energetic particles (ions, electrons, or neutral energetic atoms or molecules) impinges on a substantially planar mask (2) perforated by stencil openings (4). Transmitted beamlets (5) form a structured beam that damages the non-planar membrane substrate (1) in a highly uniform array of regularly spaced regions. FIG. 2 shows that after development in a suitable solvent, the non-planar membrane substrate (1) becomes permeated by a highly uniform array of regularly spaced pores (6). The substrate may deform from its original shape during development. FIG. 2 is an illustration of a membrane substrate after development in a suitable solvent, the non-planar membrane substrate (1) is permeated by a highly uniform array of regularly spaced pores (6). Generally, exposure of a membrane to energetic particles heats the membrane in proportion to the energy and flux density of the beam. Using a commercially available H+ ion source operating at 500 keV, for example, it is possible, in a preferred embodiment, to achieve power densities of 0.15 W/cm2 on a 3 μm thick polymeric membrane. Since energetic particle beams operate in a high vacuum of 10-5 Torr or less, the only way to remove this heat is through radiation. For an emissivity of unity, the peak temperature rise of the membrane would be less than 40° C., a temperature that all polymers could endure. However, for an emissivity of 0.1, the temperature would rise to 300° C., which would severely damage the more temperature sensitive polymers such as polyester. It may be advantageous, therefore, to apply a high thermal emissivity coating to one side of the membrane substrate prior to exposure to the energetic particle beam. The coating should be applied to the side that is opposite to the side irradiated by energetic particles. In an embodiment, the emissivity of such a coating is about greater than 0.9. In an alternate embodiment, the emissivity of such a coating is about greater than 0.8. In an alternate embodiment, the emissivity of such a coating is about greater than 0.5. However, one of ordinary skill in the art would be able to select an emissivity appropriate for the particular application. The high emissivity coating should be easily removed after the exposure, preferably during the removal of the damaged regions of the membrane substrate. There are many examples of high emissivity coatings including paints containing particles TiO2. Water soluble paints, such as black tempura, can be removed during development. Spray coating provides a practical and inexpensive way of coating just one side of the membrane substrate. FIG. 3 is an illustration of the an embodiment of the present invention where a high emissivity coating (7) is applied to the membrane to enhance radiative cooling during energetic particle exposure. The emissivity of the coating is dependent upon its thickness. In a preferred embodiment, the thickness is between 10 and 125 μm. For patterning a non-planar substrate, the dimensions of the transmitted beamlets should be essentially unchanged over the height of the topography. In the processing of polymeric sheet stock as described below, flatness is not expected to be better than 1 mm. Moreover, under high tension, most substrates form tension wrinkles, which are corrugations in the machine direction that disappear immediately after relieving tension. Substrates with buckles will usually form much larger tension wrinkles than flat substrates. As the film passes under the mask, the peaks of the tension wrinkles could scrape the mask causing it to break. Various embodiments therefore anticipate patterning over a distance of 5-10 mm from the mask. As such, various embodiments are capable of forming an image over such a large depth-of-field (DoF), defined as the maximum distance over which a particular feature size can be formed, is an important consideration. In various embodiments of a projection system, a system comprising energetic particle proximity lithography where DoF is limited primarily by the finite size of the energetic particle source is capable of being used. FIG. 4 shows that the edges of an image of a mask 52 on a substrate 51 are sharp and well-defined for a point-source 57 of particles. FIG. 5 shows that, for an extended source 60, the edges of the shadow of a mask 62 on a substrate 61 are blurred by the overlapping images created by ions emanating from different points on the source. The width β of this penumbral blur is approximately equal to the resolution limit in the printed image. Clearly, β=dσ/L where σ is the diameter of the source, d is the distance from the mask to the substrate, and L is the distance from the source to the mask. In the duoplasmatron ion source, for example, DoF can be more than 10,000 times larger than the minimum resolvable feature; thus, 1 micrometer size features can be printed on a surface located 10 mm from the mask. This implies that a freestanding membrane need only be held flat within a 5-10 mm tolerance for creating 1 micrometer pore openings. This is more than 100,000 times less constraining than the 100 nm flatness tolerances discussed by Van Rijn. FIG. 6 is an illustration of an electrostatic clamping concept for preventing substrate motion during ion exposure. A conducting substrate platen 109 is divided by an electrically insulating spacer 112 into two conducting regions 110 and 111. The polymeric membrane material is coated with a thin metal film 113 to make the top surface electrically conducting. Electrostatic forces, generated by voltages applied to conducting regions 110 and 111 then clamp the polymer to the platen. In various embodiments, the membrane substrate and the substrate platen 109 is divided by an electrically insulating spacer 112 into two regions 110 and 111. The polymeric membrane material may be coated with a thin metal film 114 to make the top surface electrically conducting and different voltages applied to regions 110 and 111. Electrostatic forces between the platen and the metal film then clamp the polymer to the platen. The flatness of the platen need only conform to the Depth of Field (DoF) specifications. Moreover, the clamping need not produce a perfectly flat polymeric film. Voids and wrinkles may be tolerated as long as they conformed to the DoF specifications. Now referring to FIG. 7, a reel-to-reel manufacturing apparatus is disclosed for manufacturing microporous filters in a continuous manner. Polymeric feed stock 210 is fed from a supply reel 213 through a series of in-feed rollers tensioner 214, capstan drive 216, and idler 218 onto the substrate platen 290 where it is exposed to an ion beam 230 through a stencil mask 200. After exposure, the membrane passes through tensioner 217, capstan drive 219, and idler 215 and wound on take-up reel 220. In various embodiments, a film processed under an embodiment of the present invention is held stationary while energetic particle exposure is taking place. This could be done with an electrostatic clamp as shown in FIG. 5 where a substrate platen 109 is divided by an electrically insulating spacer 112 into two regions 110 and 111. The polymeric membrane material may be coated with a thin metal film 114 to make the top surface electrically conducting and different voltages applied to regions 110 and 111. Electrostatic forces between the platen and the metal film then clamp the polymer to the platen. The flatness of the platen need only conform to the DoF specifications. Moreover, the clamping need not produce a perfectly flat polymeric film. Voids and wrinkles may be tolerated as long as they conformed to the DoF specifications. In an embodiment, experiments have demonstrated the patterning of a polyethylene teraphthalate (Mylar) film by 50 keV He+ ion beam irradiation using a 20% KOH/H2O developer. FIG. 8 shows the development depth as a function of ion dose for 40° C. and 60° C. development temperatures. The dose required to remove 1500 angstroms is about 6 μC/cm2. The etch depth typically is smaller than that required for fabricating membrane filters. This is because these low energy ions stop about 200 nm into the film, FIG. 9. The spreading of the ions near the end of their trajectories is also a concern because it is capable of degrading the resolution of the printed mask image. Hydrogen ions (protons) are capable of use in this regard. FIG. 10 shows that 400 keV, 600 keV, and 900 keV protons have sufficient range to penetrate mylar films of varying thickness, such as, but not limited to, 3, 4, and/or 5 micrometers with a blur of less than 0.1 micrometers. FIG. 11 a) A silicon nitride stencil mask with 0.8×1.6 μm2 openings. FIG. 10 b) is the 50 keV He+ image of the stencil mask in a) printed in a sample of Mylar sheet stock. The Mylar 1×1 in2 sheet was loosely attached to a holder with tape at the corners. The flatness of the wrinkled sample was estimated at 2 mm. The film was developed in hot KOH (40° C.). Although the energy of the helium ions was insufficient to completely penetrate the mylar film, this micrograph clearly demonstrates direct patterning of mylar with helium ions over a large depth of field.
	description	The present application claims the benefit of U.S. Provisional Application Ser. No. 61/900,200, filed Nov. 5, 2013, which is hereby incorporated by reference herein in its entirety, including any figures, tables, or drawings. Conventional scintillators have been developed for detection of high energy particles and radiation, such as x-rays, gamma-rays, neutrons, and the like. A scintillation detecting system is based on the use of a scintillation composition to convert a portion of the energy imparted to the composition by incident ionizing radiation, to light, such as visible or ultra-violet scintillation light. Absolute scintillation (or conversion) efficiency of a composition is defined as the ratio of the energy carried by the visible or ultra-violet light, to the energy lost in the composition by the incident ionizing radiation. The light emerging from a scintillator typically impinges upon some photo-electric device, e.g., a photomultiplier (PM), or charge coupled device (CCD), where it is converted into an electrical pulse. This electrical pulse is then amplified and recorded by a standard electronic data acquisition system. Details of scintillators, in general, and plastic organic scintillators, in particular, are described in publications such as the books by J. B. Birks, “The Theory and Practice of Scintillation Counting”, Pergamon Press, (1964), and by G. F. Knoll, “Radiation Detection and Measurement”, J. Wiley and Sons 1989 particularly Chapter 8. Plastic scintillators may be a solid sheet or plate or may be in the form of an optical fiber or fiber optic plate such as disclosed in European Patent Publication 0 606 732 A1, Jul. 20, 1994. Conventional plastic scintillators (ternary scintillator) typically have three components, such as a polymeric matrix, e.g., poly(vinyltoluene) (PVT), and two fluors (fluorescent compounds). The typical scintillator composition of the two fluors is a primary dye, e.g., para-terphenyl (PTP), and a secondary dye, e.g., diphenylstilbene (DPS), at concentrations of about 1% and 0.02% wt./wt., respectively. Such a scintillator material is haze free, optically transparent, solid and stable. Methods of making and using such conventional plastic scintillators are disclosed in Harrah et al., U.S. Pat. No. 4,594,179. It has been observed that the light output from the conventional scintillator does not increase as the PTP concentration is increased above 1% wt./wt. This phenomenon has been described as “concentration quenching”, and is caused by several underlying physical mechanisms. Generally, a high absolute scintillation efficiency of a scintillator composition is desirable to achieve high detection sensitivity of ionizing radiation. Scintillation efficiency is a function of several parameters, including the type of solid matrix and the type of fluors employed. Typically, light output relative to anthracene is less than 70% for plastic and the absolute scintillation efficiencies is less than about 4%. Since modern scintillator solute fluors typically have fluorescent quantum efficiencies of close to 100%, a substantial increase in plastic composition scintillation efficiency by alternative choices of fluors is unlikely. For this reason, the light output from commercial plastic scintillator has remained at less than 70% of the light output from anthracene for more than 60 years. Attempts have been made to increase scintillation efficiency of plastic scintillators by using other plastic matrixes such as polyvinylxylene, polyisopropyl styrene, and polyvinyl naphthalene, and copolymers of monomers represented in polymers listed above. Such attempts have resulted in increasing the scintillation efficiency by up to about 40%. Such approaches suffer from one or more disadvantages, such as the monomers or polymers are commercially unavailable or prohibitively expensive, or polymer compositions are brittle and subject to surface crazing or deterioration. For these reasons, none of these approaches has been pursued commercially. Addition of naphthalene to conventional plastic scintillators has been explored as a way to increase the scintillation efficiency. Brown, et al. (Nuclear Electronics 1, 15, 1959)) added naphthalene to solid plastic scintillators, where polystyrene (PS) and polymethylmethacrylate (PMMA) were used as matrices. Addition of less than about 3% by weight of naphthalene to a PS mixture containing the fluor 2,5-diphenyl oxazole (PPO), did not change maximum scintillation efficiency of the mixture. When about 10% by weight of naphthalene is added to PMMA, this polymer is transformed from an extremely inefficient matrix to one with about 50% of the scintillation efficiency of PS. J. Tymianski and J. K. Walker, U.S. Pat. No. 5,606,638, used polystyrene with 15% by weight of the following fluorescent aromatic compounds: dimethylnaphthalene, acenaphthene, and fluorene. In each case a fluorescent dye, tetraphenylbutadiene (TPB), was added at 1% weight. The purpose of the TPB was to absorb energy from the excited aromatic compound and from polystyrene and provide subsequent emission of scintillation light at about 420 nm. The relative scintillation emission output of these scintillating compositions compared to a composition containing only TPB were found to be as follows: Dimethylnaphthalene 1.51; Acenaphthene 1.49; and Fluorene 1.47. In each scintillator, there is a substantial and almost equal increase in scintillating light emission. Taking into account the fact that the quantum yields of the three aromatic compounds are 0.22, 0.6, and 0.8, respectively, it suggests that there is severe self-quenching of these dyes especially in the latter two cases. Although many efforts have been made to produce more efficient plastic scintillator material, there still exists a need to produce plastic scintillator with light output relative to anthracene of at least 125%, preferably greater than 150%, and most preferably greater than 175%. Embodiments of the subject invention relate to high efficiency plastic scintillators that emit intense light when exposed to ionizing radiation. Specific embodiments of the subject invention pertain to material compositions for providing high-intensity, scintillation light output in the presence of ions, which can be used for making scintillators more sensitive to the presence of ionizing radiation. Embodiments of the subject invention are directed to a method of detecting ionizing radiation, a much brighter scintillation material, and a scintillator system. An embodiment of the subject scintillator material composition, which can be referred to as a quaternary scintillator because it has four components, for converting the incident penetrating radiation to light (such as visible light), incorporates: 1) an amorphous polymeric matrix material; 2) a base dye dissolved in the amorphous polymeric matrix material, where the base dye incorporates a base fluorescent aromatic compound. In an embodiment, the base fluorescent aromatic compound has at least two rings. In an embodiment, the base fluorescent aromatic compound is an alkyl, aryl, phenyl, alkyl and aryl, alkyl and phenyl, aryl and phenyl, or alkyl, aryl, and phenyl substituted compound, optionally containing at least two rings. In an embodiment, the fluorescent aromatic compound is present at about 5 percent, greater than 5 percent, greater than 6, 10, 15, 20, 25, 30, and 35 percent, and/or in the range 5-10, 10-15, 15-20, 20-25, 25-30, and/or 30-35 percent, or greater than 35% of the scintillator material weight. In a preferred embodiment, the fluorescent aromatic compound is a bridged two ring compound with planar structure, high quantum efficiency, high solubility, and an emission spectrum with peak at about the same as the polymeric matrix, such as with a peak wavelength within 30%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, and/or 1% of the peak wavelength of the amorphous polymeric matrix material; 3) a primary dye dissolved in the amorphous polymeric matrix material. In an embodiment the primary dye can have a concentration of less than 0.5%, in the range 0.25 to 0.5%, 0.5 to 1%, 1 to 1.5%, 1.5 to 2%, 2 to 2.5%, 2.5 to 3%, 3 to 3.5%, 3.5 to 4%, 4 to 4.5%, 4.5 to 5%, 5 to 5.5%, 5.5 to 6%, 0.25 to 6%, 0.5-6%, 0.5 to 3%, 0.25 to 3.5%, and/or greater than 6% of the scintillator material weight. Preferably, the primary dye dissolved in the amorphous polymeric matrix material efficiently transfers energy non-radiatively to itself from both the matrix and the base dye, such as the scintillation composition having an efficiency of at least 40, 50, 60, 70, 80, 90, 95, and/or 99% for transferring energy non-radiatively to the primary dye from the base dye. In embodiments, the primary dye incorporates a primary fluorescent aromatic compound. In an embodiment, the primary fluorescent aromatic compound has at least two rings. In an embodiment, the primary fluorescent aromatic compound is an alkyl, aryl, phenyl, alkyl and aryl, alkyl and phenyl, aryl and phenyl, or alkyl, aryl, and phenyl substituted compound, optionally containing at least two rings; and 4) a secondary dye dissolved in the amorphous polymeric matrix material. In embodiments, the secondary dye can have a concentration of less than 0.005%, 0.0025 to 0.005%, 0.005 to 0.01%, 0.01 to 0.015%, 0.015 to 0.02%, 0.02 to 0.025%, 0.025 to 0.03%, 0.03 to 0.035%, 0.035 to 0.04%, 0.04 to 0.045%, 0.045 to 0.05%, 0.05 to 0.055%, 0.005 to 0.05%, 0.005 to about 0.05%, and/or greater than 0.05% of the scintillator material weight. In embodiments, the secondary dye incorporates a secondary fluorescent aromatic compound. In an embodiment, the secondary fluorescent aromatic compound has at least two rings. In an embodiment, the secondary fluorescent aromatic compound is an alkyl, aryl, phenyl, alkyl and aryl, alkyl and phenyl, aryl and phenyl, or alkyl, aryl, and phenyl substituted compound, optionally containing at least two rings. In embodiments, the secondary dye absorbs fluorescence from the primary dye and reemits fluorescence. In specific embodiments, the fluorescence reemitted by the secondary dye is in the visible region of wavelengths. The scintillation composition results when the amorphous polymeric matrix material with the base dye, primary dye, and secondary due dissolved therein is polymerized. In a further embodiment of this invention, the amorphous polymeric matrix material and base dye are employed as above, together with a single dye replacing the primary dye and the secondary dye. This single replacement dye can be designed to have a very large Stokes shift, which shifts the light into the visible range with very little light reabsorption. In a specific embodiment of the invention, the polymeric matrix is cross-linked. In another embodiment of the invention the quaternary scintillator is a liquid, incorporating: 1) an aromatic solvent, such as pseudocumene, xylene or the like; 2) a base dye dissolved in the aromatic solvent. In an embodiment, the base dye incorporates a base fluorescent aromatic compound. In an embodiment, the fluorescent aromatic compound is an alkyl, aryl, phenyl, alkyl and aryl, alkyl and phenyl, aryl and phenyl, or alkyl, aryl, and phenyl substituted compound, optionally containing at least two rings. In an embodiment, the fluorescent aromatic compound is present at about 5 percent, greater than 5 percent, greater than 6, 7, 10, 15, 20, 25, 30, 35 percent, and/or in the range 5-10%, 10-15%, 15-20%, 20-25%, 25-30%, and/or 30-35%, or greater than 35% of the scintillator material weight. In a preferred embodiment, the fluorescent aromatic compound is a bridged two ring compound with planar structure, high quantum efficiency, high solubility, and an emission spectrum with peak at about the same as the aromatic solvent, such as with a peak wavelength within 30%, 20%, 15%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, and/or 1% of the peak wavelength of the aromatic solvent; 3) a primary dye dissolved in the aromatic solvent. In an embodiment, the primary dye can have a concentration of less than 0.5%, in the range 0.25 to 0.5%, 0.5 to 1%, 1 to 1.5%, 1.5 to 2%, 2 to 2.5%, 2.5 to 3%, 3 to 3.5%, 3.5 to 4%, 4 to 4.5%, 4.5 to 5%, 5 to 5.5%, 5.5 to 6%, 0.25 to 6%, 0.5 to 6%, 0.5 to 3%, 0.25 to 3.5%, and/or greater than 6% of the scintillator material weight. Preferably, the primary dye dissolved in the amorphous polymeric matrix material efficiently transfers energy non-radiatively to itself from both the matrix and the base dye, such as the scintillation composition having an efficiency of at least 40%, 50%, 60%, 70%, 80%, 90%, 95%, and/or 99% for transferring energy non-radiatively to the primary dye from the base dye. In an embodiment, the primary dye incorporates a primary fluorescent aromatic compound. In an embodiment, the primary fluorescent aromatic compound has at least two rings. In an embodiment, the primary fluorescent aromatic compound is an alkyl, aryl, phenyl, alkyl and aryl, alkyl and phenyl, aryl and phenyl, or alkyl, aryl, and phenyl substituted compound, optionally containing at least two rings; and 4) a secondary dye dissolved in the aromatic solvent. In an embodiment, the secondary dye can have a concentration of less than 0.005%, 0.0025 to 0.005%, 0.005 to 0.01%, 0.01 to 0.015%, 0.015 to 0.02%, 0.02 to 0.025%, 0.025 to 0.03%, 0.03 to 0.035%,0.035 to 0.04%, 0.04 to 0.045%, 0.045 to 0.05%, 0.05 to 0.055%, 0.005 to 0.05%, 0.005 to about 0.05%, and/or greater than 0.05% of the scintillator material weight. In embodiments, the secondary dye incorporates a secondary fluorescent aromatic compound. In an embodiment, the secondary fluorescent aromatic compound has at least two rings. In an embodiment, the secondary fluorescent aromatic compound is an alkyl, aryl, phenyl, alkyl and aryl, alkyl and phenyl, aryl and phenyl, or alkyl, aryl, and phenyl substituted compound, optionally containing at least two rings. In embodiments, the secondary dye absorbs fluorescence from the primary dye and reemits fluorescence. In specific embodiments, the fluorescence reemitted by the secondary dye is in the visible region of wavelengths. In a further embodiment of the invention, the quaternary plastic and liquid scintillators can be used to provide pulse shape discrimination (PSD) for identifying fast neutrons in a background of gamma rays. Embodiments of the subject invention incorporate methods, systems, and/or materials taught by PCT/US2012/030606 (WO 2012/135140), published on Oct. 4, 2012, which is incorporated herein in its entirety, such as: A. a scintillation system for detecting incident radiation, incorporating: a scintillator composition for converting incident radiation to scintillation light wherein the scintillator composition comprises: a matrix material with a plurality of base fluorescent dye molecules dissolved therein, wherein the matrix material is a solid organic material, wherein the matrix material with the plurality of base fluorescent dye molecules dissolved therein comprises a plurality of chromophores, wherein the plurality of chromophores have a chromophore average nearest neighbor distance in the range 0.5 to 12 Angstroms; wherein the plurality of chromophores produces the scintillation light upon excitation; wherein the scintillation light has a prompt time component and a delayed time component, wherein the prompt time component and the delayed time component provide information so as to allow distinguishing between scintillation light created by neutrons and scintillation light created by gamma rays; B. a method for detecting incident radiation, incorporating: positioning a scintillation system in a region of interest, wherein the scintillation system comprises: a scintillator composition for converting the incident radiation to scintillation light wherein the scintillator composition comprises: a matrix material, wherein the matrix material is a solid organic material, wherein the matrix material comprises chromophores, wherein the chromophores have an average nearest neighbor distance in the range of 0.5 to 12 Angstroms; wherein the chromophores produce the scintillation light upon excitation; wherein the prompt time component and the delayed time component provide information so as to allow distinguishing between scintillation light created by neutrons and scintillation light created by gamma rays; receiving the scintillation light; and determining from the received scintillation light whether neutrons were incident on the scintillation system; and C. a scintillator composition for converting the incident radiation to scintillation light, comprising: a matrix material with a plurality of base fluorescent dye molecules dissolved therein, wherein the matrix material is a solid organic material, wherein the matrix material with the plurality of base fluorescent dye molecules dissolved therein comprises a plurality of chromophores, wherein the plurality of chromophores have a chromophore average nearest neighbor distance in the range 0.5 to 12 Angstroms; wherein the plurality of chromophores produces the scintillation light upon excitation; wherein the scintillation light has a prompt time component and a delayed time component, wherein the prompt time component and the delayed time component provide information so as to allow distinguishing between scintillation light created by neutrons and scintillation light created by gamma rays. In another embodiment of the invention, the quaternary plastic and liquid scintillators can be used to provide pulse shape discrimination (PSD) for identifying thermal neutron capture by Lithium-6 in a background of gamma rays. Embodiments of the subject invention incorporate methods, systems, and/or materials taught by PCT/US2013/065307, filed on Oct. 16, 2013, which is incorporated herein in its entirety, such as: D. a scintillation system for detecting incident radiation, comprising: a scintillation composition, wherein the scintillation composition comprises: a matrix material; and chromophore dye molecules dissolved in the matrix material, wherein the chromophore dye molecules self-assemble to form dimeric chromophores, wherein a concentration of the dimeric chromophores is such that the dimeric chromophores have an average nearest neighbor distance in the range 2 to 15 Angstroms, wherein the dimeric chromophores produce excimer scintillation light upon excitation, wherein the excimer scintillation light has a prompt component and a delayed component, wherein the delayed time component is excimer scintillation light that is produced a delay period of time after excimer scintillation light of the prompt component is produced, wherein an intensity of the prompt component and an intensity of the delayed component provide information so as to allow distinguishing between excimer scintillation light created by a fast neutron being incident on the scintillation composition and excimer scintillation light created by a gamma ray being incident on the scintillation composition; E. a scintillation system for detecting incident radiation, comprising: a scintillation composition, wherein the scintillation composition comprises: a matrix material; and chromophore dye molecules dissolved in the matrix material, wherein the chromophore dye molecules self-assemble to form dimeric chromophores, wherein a concentration of the dimeric chromophores is such that the dimeric chromophores have an average nearest neighbor distance in the range 2 to 15 Angstroms, wherein the dimeric chromophores produce excimer scintillation light upon excitation, wherein the excimer scintillation light has a prompt component, wherein the prompt component comprises a first prompt sub component and a second prompt subcomponent, wherein the second prompt subcomponent is produced a second delay period of time after the first prompt subcomponent, wherein the second delay period of time is in the range 0.3 to 3 ns, wherein an intensity of the first prompt subcomponent and an intensity of the second prompt subcomponent provide information so as to allow distinguishing between excimer scintillation light created by a fast neutron being incident on the scintillation composition and excimer scintillation light created by a gamma ray being incident on the scintillation composition; F. a scintillation system, comprising: a matrix material; and isotope Li-6, wherein the system provides information for identifying nuclear fragments resulting from thermal neutron capture by isotope Li-6 and discriminate with a factor of at least 100,000:1 against electron recoils from gamma ray scatters in the matrix material; G. a scintillation system, comprising: a matrix material; and isotope Li-6, wherein the system provides information for identifying nuclear fragments resulting from thermal neutron capture by isotope Li-6 and discriminates with a factor of at least 10,000:1 and/or 100,000:1 against electron recoils from gamma ray scatters in the matrix material; H. a scintillation system, comprising: a matrix material; and isotope B-10, wherein the system provides information for identifying nuclear fragments resulting from thermal neutron capture by isotope B-10 and discriminates with a factor of at least 100,000:1 against electron recoils from gamma ray scatters in the matrix material; and I. a scintillation system, wherein the system provides information to identify recoil protons over a range of energies from fast neutron scatters in the matrix material, identify nuclear fragments resulting from thermal neutron capture within the matrix material, and discriminate with a factor of at least 1,000:1 and/or 100,000:1 against electron recoils from gamma ray scatters in the matrix material. The conventional plastic scintillator, which has been used for sixty years has been termed ternary because it is composed of three components, namely a polymer, a primary dye at about 1% wt./wt., and a secondary dye at a concentration of about 0.02% wt. /wt. The mechanism producing concentration quenching of the primary dye at 1% wt./wt. has been investigated. Embodiments of the subject invention can employ a substituted form of the standard primary dye, PTP. The dye, di-t-pentyl-p-terphenyl can be synthesized and incorporated in samples of a conventional plastic scintillator. A primary dye structure, as shown in FIG. 1, can be used, where the compound has a maximum solubility of 6% in polystyrene (PS). The measured data on light output versus concentration of di-t-pentyl-p-terphenyl is shown in FIG. 2. The data shows experimentally that “concentration-quenching” can be substantially reduced in this iconic case. The light output continues to increase beyond the conventional maximum at 1% wt./wt. up to the solubility limit at about 6% wt. /wt. The total light output increase is about 35%, or 40%. This result can be attributed to an excited state of the di-t-pentyl-p-terphenyl molecule having less chance of being quenched by another di-t-pentyl-p-terphenyl molecule, because the chromophores are kept sufficiently apart by the substituents to preventing quenching. Despite achieving a 35%, or 40%, increase in light output, it is difficult to reach the desired scintillator efficiencies with a ternary scintillating structure. Embodiments of a quaternary polystyrene scintillator containing naphthalene with diisopropyl substituents were produced and the scintillation light output measured. Embodiments can incorporate materials and methods from J. Thomson, U.S. Pat. No. 4,657,696, which is hereby incorporated by reference in its entirety, where Thomson introduces a mixed isomer form of diisopropylnaphthalene (DIN) as a base liquid dye for liquid scintillator, to achieve a reduced quenching of scintillation light, and the same can be incorporated with embodiments of the subject invention. Embodiments can incorporate scintillating plastic materials, containing increasing concentrations of DIN, from 0-5%, 5-10%, and/or 10-15%, 15-20%, 20%-25%, 25-30%, 30-35%, and/or greater than 35%. The primary and secondary dyes, such as PTP and POPOP at concentration of 1% and 0.02% wt/wt, respectively, can be incorporated. The measured light output for specific embodiments incorporating DIN of 0%, 5%, 10%, or 15% wt/wt, primary dye PTP of 1% wt/wt, and secondary dye POPOP of 0.02% wt/wt is shown in FIG. 3. A comparison can be made between the previously reported Tymianski and Walker measurement of 51% light increase using dimethylnaphthalene with the above result of 95% light increase using diisopropylnaphthalene at fixed concentration of 15% wt./wt. It appears that the more bulky isopropyl substituents have reduced the self-quenching of the excited states of the naphthalene chromophore, in accordance with embodiments of the subject invention. In FIG. 3 it can be seen that the light output from a four component, quaternary, plastic scintillator, in accordance with the subject invention, has been shown to increase by almost a factor of 2 for high concentration of a quench resistant substituted base dye. This corresponds to a plastic scintillator with 140% of the light output of anthracene. It is desirable to achieve high light output with a low concentration of base dye, and preferably the minimum concentration of base dye needed for the desired light output, as a high concentration of an additive in the form of base dye reduces the glass transition temperature of the polymeric matrix and lowers the maximum operating temperature of the material. Embodiments relate to a high efficiency scintillator material having acceptable mechanical and thermal properties. Based on the total weight of the scintillator material, embodiments of the subject scintillator material contain about 5%, at least 5%, at least 6%, and/or at least 10% by weight, or more, of a bridged aromatic fluorescent compound. Aromatic compounds that can be utilized include, but are not limited to, bridged biphenyl and naphthalene. Table 1 shows examples of such compounds and some of their properties. TABLE 1Base Chromophores for Quaternary Plastic Scintillator.Candidate Base Dye9,10-FluorophoresFluoreneDihydrophenanthreneDibenzofuranAcenaphtheneStructure Quantum Yield0.80.550.530.6Fluorescence Lifetime106.67.346(ns)Stokes Loss (Cm−1)1430200019001600Emission Average313322318310Wavelength (nm)Melting Point (° C.)1113081106Measured Maximum30%expected >40%expected 35%30%Solubility % wt/wt inStyrene at 25° C.Cost per Gram50¢$1$248¢ Importantly, these base dyes have planar structures, high quantum efficiencies, emission fluorescence maxima at the emission maxima of polystyrene and polyvinyl toluene, very high solubility, and are all commercially available. In order to reduce, and preferably minimize, self-quenching, in order to achieve high light output, the dyes can be provided with substituents. Many such compounds are also commercially available. To illustrate how the dyes can be provided with substituents, chromophore fluorene, which has the highest quantum yield of the group and is an attractive potential base chromophore, is used as an example. Table 2 shows some commercially available substituted forms of fluorene. TABLE 2A few Commercially Available Substituted Fluorene Compounds.CompoundFormulaMeltingNameStructureWeightPoint ° C.9-Fluorenyl- methanol196105 9-Fluorene- 9,9 Dimethanol226142 9-Fluorene- carboxal- dehyde- diethyl acetal268 96 It should be emphasized that the photo-physical properties of the 9-C substituted fluorene compounds are essentially unaffected by substitutions because of the planar rigidity of the chromophore and symmetry of the unique location (9-C) of substituents. Of course, larger and more bulky substituent groups can be made to further enhance the resistance to self-quenching of the excited chromophores. The other base dyes in Table 2 have similar characteristics. There are commercially available substituted compounds based on these chromophores that can be utilized in accordance with various embodiments. Embodiments of the subject plastic scintillator, which can be much brighter than previous plastic scintillators, can be used in applications, such as the hadron collider calorimeters, employing hundreds of thousands of very small, thin, scintillating plates, and can, in addition, provide superior pulse shape discrimination for neutron detection for materials analysis, Nuclear Non-Proliferation, Nuclear Security, and Homeland Security. In these applications, neutron discrimination against gamma rays is limited by the light output intensity in the tail of the scintillation pulse. For these reasons, embodiments of the subject scintillating material, which can be much brighter than previous scintillating material, can be an enabling technology for many applications. Embodiment 1. A scintillation system, comprising: a scintillation composition, wherein the scintillation composition comprises: an amorphous polymeric matrix material; a base dye dissolved in the amorphous polymeric matrix material, wherein the base dye incorporates a base fluorescent aromatic compound, and wherein the base fluorescent aromatic compound is at least 5% wt/wt of the scintillation composition; and a primary dye dissolved in the amorphous polymeric matrix material, wherein the primary dye is at least 0.25% wt/wt of the scintillation composition, and wherein when ionizing radiation is incident on the scintillation composition, the primary dye emits primary fluorescence. Embodiment 2. The scintillation system according to Embodiment 1, further comprising: a secondary dye dissolved in the amorphous polymeric matrix material, wherein the secondary dye is at least 0.005% wt/wt of the scintillation composition, and wherein primary fluorescence emitted by the primary dye is absorbed by the secondary dye such that the secondary dye emits secondary fluorescence. Embodiment 3. The scintillation system according to Embodiment 1, wherein the base fluorescent aromatic compound has at least two rings. Embodiment 4. The scintillation system according to Embodiment 1, wherein the base fluorescent aromatic compound is an alkyl, aryl, or phenyl substituted compound. Embodiment 5. The scintillation system according to Embodiment 1, wherein the base fluorescent aromatic compound is an alkyl and aryl substituted compound. Embodiment 6. The scintillation system according to Embodiment 1, wherein the primary dye comprises a primary fluorescent aromatic compound. Embodiment 7. The scintillation system according to Embodiment 1, wherein the base fluorescent aromatic compound is a bridged at least two ring compound with a planar structure. Embodiment 8. The scintillation system according to Embodiment 1, wherein the primary dye incorporates a primary fluorescent aromatic compound, and wherein the primary fluorescent aromatic compound is in the range 0.25 to 6% wt/wt of the scintillation composition. Embodiment 9. The scintillation system according to Embodiment 1, wherein the scintillation composition has an efficiency of transferring energy non-radiatively to the primary dye from the base dye of at least 40%. Embodiment 10. The scintillation system according to Embodiment 2, wherein the secondary dye is in the range 0.005 to 0.05% of the scintillation composition. Embodiment 11. The scintillation system according to Embodiment 10, wherein at least a portion of the secondary fluorescence is visible. Embodiment 12. The scintillation system according to Embodiment 1, wherein at least a portion of the primary fluorescence is visible. Embodiment 13. The scintillation system according to Embodiment 1, wherein the amorphous polymeric matrix material is cross-linked. Embodiment 14. The scintillation system according to Embodiment 1, wherein the base fluorescent aromatic compound is at least 15% wt/wt of the scintillation composition. Embodiment 15. The scintillation system according to Embodiment 1, wherein the scintillation composition has an efficiency of transferring energy non-radiatively to the primary dye from the base dye of at least 60%. Embodiment 16. A scintillation system, comprising: a scintillation composition, wherein the scintillation composition comprises: an aromatic solvent; a base dye dissolved in the aromatic solvent; wherein the base dye incorporates a base fluorescent aromatic compound, and wherein the base fluorescent aromatic compound is at least 5% wt/wt of the scintillation composition; and a primary dye dissolved in the aromatic solvent, wherein the primary dye is at least 0.25% wt/wt of the scintillation composition, and wherein when ionizing radiation is incident on the scintillation composition, the primary dye emits primary fluorescence. Embodiment 17. The scintillation system according to Embodiment 16, further comprising: a secondary dye dissolved in the aromatic solvent, wherein the secondary dye is at least 0.0025% wt/wt of the scintillation composition, and wherein the secondary dye absorbs the primary fluorescence from the primary dye and emits secondary fluorescence. Embodiment 18. The scintillation system according to Embodiment 16, wherein the aromatic solvent is pseudocumene or xylene. Embodiment 19. The scintillation system according to Embodiment 16, wherein the base fluorescent aromatic compound has at least two rings. Embodiment 20. The scintillation system according to Embodiment 16, wherein the base fluorescent aromatic compound is an alkyl, aryl, or phenyl substituted compound. Embodiment 21. The scintillation system according to Embodiment 16, wherein the base fluorescent aromatic compound is an alkyl and aryl substituted compound containing at least two rings. Embodiment 22. The scintillation system according to Embodiment 16, wherein the base fluorescent aromatic compound is at least 15% wt/wt of the scintillation composition. Embodiment 23. The scintillation system according to Embodiment 16, wherein the base fluorescent aromatic compound is a bridged at least two ring compound with a planar structure. Embodiment 24. The scintillation system according to Embodiment 16, wherein the base dye is a mixed isomer form of diisopropylnaphthalene. Embodiment 25. The scintillation system according to Embodiment 24, wherein the primary dye is PTP, and wherein the secondary dye is POPOP. Embodiment 26. The scintillation system according to Embodiment 1, wherein the base dye is a mixed isomer form of diisopropylnaphthalene. Embodiment 27. The scintillation system according to Embodiment 26, wherein the primary dye is PTP, wherein the secondary dye is POPOP. Embodiment 28. The scintillation system according to Embodiment 4, wherein the base fluorescent aromatic compound is an alkyl substituted compound, and wherein the alkyl substituted compound is fluorenecarboxaldehyde diethyl acetal. Embodiment 29. The scintillation system according to Embodiment 20, wherein the base fluorescent aromatic compound is an alkyl substituted compound, and wherein the alkyl substituted compound is fluorenecarboxaldehyde diethyl acetal. Embodiment 30. A scintillation system, comprising: a polymeric matrix; a primary dye dissolved in the polymeric matrix, wherein the primary dye is di-t-pentyl-p-terphenyl, and wherein when ionizing radiation is incident on the scintillation composition the primary dye emits primary fluorescence; and a secondary dye dissolved in the polymeric matrix, wherein the secondary dye absorbs the primary fluorescence and emits secondary fluorescence, and wherein at least a portion of the secondary fluorescence is visible. While the foregoing written description of the invention enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiment, method, and examples herein. The invention should therefore not be limited by the above described embodiment, method, and examples, but by all embodiments and methods within the scope and spirit of the invention. Aspects of the invention, such as receiving, processing, and outputting detection signals and indications, may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types. Moreover, those skilled in the art will appreciate that the invention may be practiced with a variety of computer-system configurations, including multiprocessor systems, microprocessor-based or programmable-consumer electronics, minicomputers, mainframe computers, and the like. Any number of computer-systems and computer networks are acceptable for use with the present invention. Specific hardware devices, programming languages, components, processes, protocols, and numerous details including operating environments and the like are set forth to provide a thorough understanding of the present invention. In other instances, structures, devices, and processes are shown in block-diagram form, rather than in detail, to avoid obscuring the present invention. But an ordinary-skilled artisan would understand that the present invention may be practiced without these specific details. Computer systems, servers, work stations, and other machines may be connected to one another across a communication medium including, for example, a network or networks. As one skilled in the art will appreciate, embodiments of the present invention may be embodied as, among other things: a method, system, or computer-program product. Accordingly, the embodiments may take the form of a hardware embodiment, a software embodiment, or an embodiment combining software and hardware. In an embodiment, the present invention takes the form of a computer-program product that includes computer-useable instructions embodied on one or more computer-readable media. Computer-readable media include both volatile and nonvolatile media, transitory and non-transitory, transient and non-transient media, removable and nonremovable media, and contemplate media readable by a database, a switch, and various other network devices. By way of example, and not limitation, computer-readable media comprise media implemented in any method or technology for storing information. Examples of stored information include computer-useable instructions, data structures, program modules, and other data representations. Media examples include, but are not limited to, information-delivery media, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD), holographic media or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage, and other magnetic storage devices. These technologies can store data momentarily, temporarily, or permanently. The invention may be practiced in distributed-computing environments where tasks are performed by remote-processing devices that are linked through a communications network. In a distributed-computing environment, program modules may be located in both local and remote computer-storage media including memory storage devices. The computer-useable instructions form an interface to allow a computer to react according to a source of input. The instructions cooperate with other code segments to initiate a variety of tasks in response to data received in conjunction with the source of the received data. The present invention may be practiced in a network environment such as a communications network. Such networks are widely used to connect various types of network elements, such as routers, servers, gateways, and so forth. Further, the invention may be practiced in a multi-network environment having various, connected public and/or private networks. Communication between network elements may be wireless or wireline (wired). As will be appreciated by those skilled in the art, communication networks may take several different forms and may use several different communication protocols. And the present invention is not limited by the forms and communication protocols described herein. All patents, patent applications, provisional applications, and publications referred to or cited herein are incorporated by reference in their entirety, including all figures and tables, to the extent they are not inconsistent with the explicit teachings of this specification. It should be understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application.
	description	This invention relates to a detector apparatus and method for the inspection and characterisation of material in three-dimensional space. The invention in particular preferably relates to an apparatus and method making use of high energy radiation such as x-rays or gamma-rays to scan objects and generate spatially resolved information about their contents and/or composition based on radiation received at a detector after interaction with the object, and preferably to generate an image therefrom. The invention in particular preferably relates to the measurement of transmitted intensity to gain information about the internal contents and/or composition of objects. The invention in a preferred case relates in particular to a detector apparatus and method for the production of a two-dimensional image, but is not limited to such imaging. This scanning principle is widely employed for example, without limitation, in medical imaging, imaging for quality control purposes or the purposes of determining the integrity of the structure, security scanning or the like. X-Ray absorption in particular has been used as the basis for systems for scanning objects to create some form of representational image of the contents or components thereof. The thicker or more dense an object is then the more it will attenuate an x-ray beam. By use of suitable detectors and a suitable source, radiographs of an item under screening in the form of images based on the absorption of an object or set of objects can be generated. Typically, an x-ray source generates an essentially two-dimensional beam and detectors of transmitted x-rays in one or two dimensional array are used to resolve transmitted information spatially into two dimensions based on transmitted x-rays (and hence differentiating by absorption). A computer is used to generate a two-dimensional image of the object from this spatially resolved information. In a refinement, it is known to build up successive two-dimensional image slices in cross-section and display these successively. Such a principle is employed in CAT scanning for example. Similar principles can be applied to imaging based on other interactions of source and object, for example based on backscattered radiation. These known apparatus and methods tend to give limited information about the material content. In essence, at its simplest, all that is being measured is transmissivity of the object to the source radiation. Conventional detectors merely collect amplitude information discriminated spatially, but do not discriminate transmitted radiation spectroscopically. However, it is known that spectroscopic information from transmitted x-rays could be used to give additional information about the material content of the objects or components being scanned. It is known that the x-ray absorption properties of any material can vary spectroscopically, and that the amount by which the absorption properties vary depends in particular on atomic number. Silicon-based dual band energy detectors have been used to generate pairs of images as low and high energy allowing some spectroscopic discrimination. Recent development of detector materials that can resolve spectroscopic information about the transmitted X-rays more effectively has led to the development of apparatus that discriminate across a larger range of bands and generate a larger plurality of spectroscopically differentiated images. For example U.S. Pat. No. 5,943,388 describes a system that makes use of cadmium telluride detectors to image across at least three energy bands and generate at least three images. Such systems better exploit the effect of differential spectral absorption by different materials and enable a better approximation to be made between transmissivity and composition. However, the detector materials are expensive and difficult to fabricate, particularly if configured as a linear or area array with high pixel resolution. It is an object of the present invention to mitigate some or all of the above disadvantages of prior art scanning systems and methods. It is a particular preferred object of the present invention to provide an apparatus and method for scanning and preferably further for imaging of objects, that makes effective and practical use of resolution of radiation produced by interaction of a scanned object both spatially and spectroscopically. Therefore, according to one aspect of the invention there is provided a detector apparatus for scanning of and obtaining radiation data from, and preferably an image of, an object comprising: a radiation source; a radiation detector system spaced therefrom to define a scanning zone and to collect in use a dataset of information about radiation incident at the detector after interaction with an object in the scanning zone and adapted to resolve such collected information spatially in two dimensions across a scan area and spectroscopically across a plurality of frequency bands in the spectrum of the source; wherein the detector system is adapted to resolve such collected information spectroscopically in that it comprises a detector that exhibits a spectroscopically variable response across at least a part of the spectrum of the source; and wherein the detector system is adapted to resolve such collected information spatially in that it comprises: a rastering module configured to divide the scanning area into a plurality of pixels in each of two dimensions; a detector control means to move the detector across the scanning area to scan such pixels successively and thereby collect a dataset for each pixel. The apparatus is distinctly characterised from many conventional x-ray scanning and imaging systems in two particular ways. First, a detector is used which exhibits a spectroscopically variably response across at least a part of the spectrum of the source, and preferably at least a major part of the spectrum of the source, the apparatus then being adapted, for example by provision of suitable data processing means, to resolve radiation information collected at the detector spectroscopically across a plurality frequency bands. Preferably, the detector is adapted to resolve such collected information spectroscopically across at least three frequency bands. Conveniently, it achieves this in that it is fabricated from a material inherently capable of exhibiting a spectroscopically variable response across at least part of the spectrum of the source. This spectroscopic resolution offers potentially significant advantages over prior art systems comprising simple detectors without energy resolution, and in the case of the preferred embodiment where radiation is resolved spectroscopically across at least three energies, over dual energy detectors. Single energy detectors give no information about variation in incident intensity with frequency attributable to the composition of an object. Dual energy detectors allow only very crude general approximations to be drawn. More complete spectral resolution enables data to be collected from which more specific inferences can be drawn. The use of material that resolves spectroscopically across a substantial part of the source is particularly advantageous. The detector is capable of detecting and collecting spectroscopically resolvable information about incident radiation in the sense that it is adapted to differentiate incident radiation simultaneously into plural separate energy bands across the spectrum of the source. For example, the detector exhibits a spectroscopically variable response across at least a part of the source spectrum allowing such simultaneous differentiation of incident radiation into plural energy bands. However, such materials can be difficult to fabricate with the necessary spatial resolution. Accordingly, the invention is further characterised in that an image is built up on a raster principle by movement at least of the detector in at least two dimensions so as to collect data from a two dimensional scanning area. A scanning area is defined and a rastering module divides the scanning area into a plurality of pixels in each of two dimensions. The rastering module notionally divides the scanning area into an array of pixels extending over two dimensions in any suitable shape, for example forming a square or hexagonal array, at a desired resolution (that is, pixel size). However, the apparatus of the invention does not require the detector to exhibit this resolution across the full scanning area, nor even to have this resolution fully in either dimension. Instead, a detector which resolves substantially fewer pixels in each dimension, and which may even simply detect a single pixel at a time, and for example thereby present a substantially smaller detector area than the scan area, is caused to move in two dimensions across the scan area plane and thus collect successively information about the pixels defined by the rastering module until such time as a complete dataset has been built up of information for each pixel. The system can confer two advantages in particular. First, it is not necessary for the detector to extend across the full desired scan area or to be in itself to be capable of resolving information spatially across the scan area to a desired pixel size. This can produce significant advantages in terms of practicality of fabrication and cost, particularly with materials which are used to give full spectral resolution at higher energies where achievement of fine-scale resolution by structural features alone can be complex. Second, because the resolution is essentially a function of the rastering system and not of the detector, an apparatus can be readily switched between multiple resolutions, which can greatly enhance the flexibility of the apparatus. For example, it can be seen that the raster module could define a coarse scan of a large object in the first instance based on a relatively large notional pixel size, and a fine detail focused scan on elements or components of an object identified thereby. Preferably therefore the rastering module is configured to divide the scanning area into a plurality of pixels in each of two dimensions at a plurality of resolutions (for example, a plurality of pixel sizes), including at least a coarse and a fine resolution, and is further configured to enable selection between the plurality of resolutions, for example by a user through a suitable user input interface. The apparatus of the invention could be included as an addition in an existing luggage/baggage/container screening system. Such an existing/established x-ray luggage screening systems such as a dual x-ray screening system could be used to identify in luggage/container suspect items that need further investigation/analysis. The apparatus of the invention could then be used for more detailed imaging of the suspect items and would offer cost advantages over known technology for detailed screening of suspect items in luggage, such as CT imaging systems. Items of luggage/containers identified as having suspect items requiring further investigation could be passed from the established luggage/container screening system to the apparatus of the invention for detailed scanning. A coarse scan of the item of luggage/container could be carried out to identify the area for further investigation and then a fine detailed scan of the area of interest could be made. Alternatively, the area of interest for further investigation could be identified in the established luggage/container screening system and the coordinates identified and the reference coordinates passed to the apparatus of the invention by known communication means to enable a detailed scan only of the area of interest to be conducted without the need for a coarse scan. In a preferred embodiment, the detector apparatus is configured to detect transmitted radiation for example for use in generation of a transmission radiograph in familiar manner. X-ray absorption in particular shows a resolvable functional variation that can be related to material composition, and x-ray transmission information which is resolved spectroscopically across the plurality frequency bands can exploit this. Thus, in a preferred embodiment, the apparatus comprises a radiation source and a radiation detector system space therefrom to define a scanning zone in a radiation transmission path therebetween and thus collect in use a dataset of information about transmissivity of an object in the scanning zone. However, the principles of the invention can be applied to the collection of information based on other interactions of source radiation and object. The radiation source preferably comprises a source to deliver high-energy radiation such as ionizing radiation, for example high energy electromagnetic radiation such as x-rays and/or gamma rays, or subatomic particle radiation, and the detection system is adapted correspondingly to detect radiation in this spectrum. The radiation source for example is a broadband x-ray or gamma-ray source capable of producing broad spectrum emission over a wide range of x-ray or gamma-ray energies. Such a source will be familiar, and is widely used. The collected transmission data is resolved spectroscopically across the plurality of frequency bands. Optionally, the apparatus is adapted to collect in use radiation intensity data with an object in a single scanning position and for example includes a means to retain an object in a scanning position such as a receptacle into which an object can be placed. Additionally or alternatively it may include a conveyor to convey an object into and out of such scanning position. Optionally, the apparatus is adapted to collect in use radiation intensity data with an object in a plurality of scanning positions as the object moves relative to and for example through the scanning zone, and preferably to collect in use data for an image of an object in the scanning zone, and preferably a succession of images as the object moves through the scanning zone, in that it further comprises an object handler to cause an object to move relative to and for example through the scanning zone in use. The apparatus of the invention conveniently comprises a data processing apparatus including or constituting one or more of the rastering module, a means to resolve the collected dataset spectroscopically, means to generate a spectroscopically and spatially resolved image dataset etc. Any suitable form of data processing apparatus combining suitable hardware and software and combining automatic and user-input steps can be envisaged. For example the apparatus of the invention comprises a suitably programmed data processing apparatus such as a suitably programmed general purpose or special purpose computer. It will be understood that although reference is made herein for convenience to the scanning of an object this should not be considered to limit the application of the invention to the scanning of single homogenous objects. Indeed, for many envisaged applications, an “object” is likely to consist of multiple heterogeneous materials and/or to be a container or other agglomeration of multiple articles, so that any transmitted radiation path is likely to pass through multiple different materials having varied properties. One of the particular advantages of the invention is that it can facilitate resolution of such varied materials. The key to the apparatus of the invention is that it provides a convenient means to resolve instant radiation at the detector both spatially and spectroscopically, and in particular in the preferred embodiment to build up a dataset of transmitted information resolved across two spatial dimensions and a plurality of frequencies/energies in the spectrum of the source. Such a dataset might be susceptible to a variety of uses for subsequent numerical analysis for example, in particular to use the spectroscopically resolved data to infer information concerning composition. It is not necessary in accordance with the invention for the apparatus to generate an image. As set out hereinabove, an apparatus in accordance with the invention may be used in conjunction with a conventional imaging apparatus, for example as a second level check for a suspect item identified by such conventional imaging apparatus. However, for practical purposes it may be preferable that the apparatus in accordance with the invention itself forms part of and supplements the information offered by a scanning imaging system. In accordance with this preferred embodiment, the dataset of information collected at the detector is used to generate an image of an object in the scanning zone resolved in two dimensions in accordance with the raster pattern and resolved spectroscopically across a plurality of frequency bands within the spectrum of the source. Optionally, the apparatus further includes an image generation apparatus to generate at least a first image from the output of the detector system; and optionally further an image display adapted to display at least the first image. An image generation apparatus may in particular be adapted to receive datasets of intensity data from a plurality of spectroscopically resolved energy bands and display these separate datasets of intensity data as separate images successively or simultaneously to aid in object differentiation. For example spectroscopic differentiation in the collected data may be represented in a single combined image as differentiated colour, shading or marking. The display means is conveniently a simple two dimensional display screen, for example a conventional video display screen (which term is intended to encompass any direct display or projection system exploiting any cathode ray tube, plasma display, liquid crystal display, liquid crystal on silicon display, light emitting diode display or like technology). It is a particular advantage that the method can be envisaged for use with, and the apparatus of the invention incorporated into, the standard display screens of comparable existing systems for example in the quality control, security or medical imaging fields. For clarification it should be understood that where used herein a reference to the generation of image is a reference to the creation of information dataset, for example in the form of a suitable stored and manipulatable data file, from which a visual representation of the underlying structure of the object under investigation could be produced, for example in a suitable image data format, and references to displaying this image are references to presenting an image generated from such a dataset in a visually accessible form, for example on a suitable display means. Image encompasses a moving image. The detector is capable of resolving the source spectrum into a plurality of energy “bands”. The exact bandwidth is not directly pertinent to the invention and useful results can be obtained by any suitable approach to dividing the spectrum, either in whole or in part, into separate energy ranges. For example, the entire spectrum or a substantial part thereof may simply be divided between such a plurality of bandwidths, and each data item be considered as a measure representative of incident radiation intensity across the entire band, and for example an average intensity. Alternatively, a plurality of relatively wide bands, but with discrete gaps therebetween, may be envisaged and analysed on the same basis. Alternatively, “bands” may be narrow even to the point where they essentially approximate to an evaluation of intensity at a single energy. As used herein the concept of collected intensity at an energy “band” includes evaluation of intensity at such a discrete single energy as well as evaluation of intensity at an energy across a narrow or broad bandwidth. Similarly the source may be a single broad spectrum source across which a plurality of bandwidths or single energies may be identified. Alternatively or additionally sources may be provided having narrow bandwidths or generating incident radiation at one or more discrete energies to provide some of the energies for comparison in accordance with the method of the invention. In this case the radiation source is a plural source comprising a combination of sources at different energies to provide the necessary total spectrum spread to allow resolution by the detector across a plurality of energies/energy bands. For example a plural source may comprise an x-ray source having a relatively lower energy spectrum, for example operating below 60 keV and for example at 10 to 50 keV and one or more other sources such as radioisotope sources generating radiation at higher energies, for example above 100 keV. A detector in accordance with the invention may simply comprise a single pixel detector (i.e., does not itself produce any spatial differentiation of incident radiation in either dimension), with the raster module enabling a full two dimensional dataset to be developed and collected via any suitable scanning pattern over time. However, the invention does not exclude the provision of a detector in which the detector itself has a differentiating resolution of a plurality of pixels in one or two directions. The requirement of the invention is that nevertheless such a composite detector is used to build up a rastered image, and will therefore in practice not be required to be configured with a structure having the desired maximum resolution of the scanning apparatus as a whole and/or not be required to have an area corresponding to the full maximum desired scan area of the apparatus as a whole. In a preferred embodiment, the detector is a single pixel detector and the apparatus builds up a two dimensional dataset entirely by the raster process. The general principles of rastering a two-dimensional data set, for example, for the purposes of producing information presentable as an image, are well known, and the precise method by which a notional raster bitmap is built up for the scanning area, and by which this area is scanned to collect the necessary data to make up the rastered data structure, are not specifically pertinent to the invention. Typically, as will be familiar, the raster module will divide the scan area into a notional grid of pixels, and in particular to a rectangular grid, from which data will be collected by scanning, at least by moving the detector, in any suitable scan pattern which covers the whole scan area in a convenient manner. Data thus resolved into two special dimensions is stored bit for bit, pixel by pixel. Such data can for example be used to generate a pixel by pixel bitmap image data set, but in accordance with the invention data corresponding to this rastered grid pattern can also be used for none-imaging purposes. The number of bits of data which are stored for each pixel will be determined by the intended application. The special resolution of each pixel will be determined as appropriate to the application. It is an advantage of the invention that the special resolution is an artifact of the virtual pixel size created by the raster module and not of a physical pixelated resolution on the detector, and is therefore flexible. It is necessary that the detector system is enabled to detect radiation in a manner which is spectroscopically resolvable. Preferably, a detector comprises a material that is adapted to produce spectroscopic resolution in that it exhibits a direct spectroscopic response. In particular a fabricated from a material selected to exhibit inherently as a direct material property a direct variable electrical and for example photoelectric response to different parts of the source spectrum. For example, the detector comprises a wide direct bandgap semiconductor material. For example, the detector comprises a semiconductor material or materials preferably formed as a bulk crystal, and for example as a bulk single crystal (where bulk crystal in this context indicates a thickness of at least 500 μm, and preferably of at least 1 mm). The materials making up the semiconductor are preferably selected from cadmium telluride, cadmium zinc telluride (CZT), cadmium manganese telluride (CMT), germanium, lanthanum bromide, thorium bromide. Group II-VI semiconductors, and especially those listed, are particularly preferred in this regard. The materials making up the semiconductor are preferably selected from cadmium telluride, cadmium zinc telluride (CZT), cadmium manganese telluride (CMT) and alloys thereof, and for example comprise crystalline Cd1−(a+b)MnaZnbTe where a and/or b may be zero. By analogy, in accordance with a further aspect of the invention there is provided: a method of obtaining radiation interaction data and for example transmission data from, and preferably an image of, an object comprising the steps of: providing a radiation source such as an x-ray or gamma-ray source and a radiation detector system such as an x-ray or gamma-ray detection system spaced therefrom to define a scanning zone therebetween, wherein the detector system is adapted to resolve such collected information spectroscopically in that it comprises a detector that exhibits a spectroscopically variable response across at least a part of the spectrum of the source; defining a scanning area for collection of radiation incident at the detector; dividing the scanning area into a plurality of pixels in each of two dimensions; moving the detector across the scanning area to scan such pixels successively and thereby collect a dataset for each pixel of information about radiation incident at the detector after interaction with an object in the scanning zone; resolving each such dataset spectroscopically across a plurality of frequency bands within the spectrum of the source. Thus, in accordance with the method, a spectroscopically resolved dataset is also developed as a dataset spatially resolved in two dimensions, with the spatial resolution attributable at least in part to a raster scanning process comprising moving at least the detector so as to perform an information collection scan across the scanning area in each of the two dimensions in an appropriate scanning pattern necessary to collect a dataset of information for each pixel. In a preferred embodiment of the method, the detector is simply a single pixel detector, and the complete dataset is assembled by scanning each pixel individually. However, the invention admits the possibility of using a detector with some degree of resolution in one or two dimensions while the method still involves building up a rastered dataset conferring the advantage that such a detector need not be a limiting factor in the maximum resolution and/or maximum scan area of the dataset generated in accordance with the method. The invention is not limited in its application to the scanning and/or imaging of objects moving through a scanning zone in a scanner. Information pertinent to the material composition of an object or objects in a transmission path can be obtained by a single scanning event, for example of a stationary object being scanned by a single beam of appropriate two-dimensional geometry. In such circumstance the method merely includes placing the object in a scanning zone to obtain such a single scan and single dataset of intensity data. However, in a preferred embodiment information is collected regarding the object under test in the scanning zone in a plurality of scanning positions between which the object is translated and/or rotated. In accordance with this embodiment of the method, the method comprises the additional step of causing an object to move relative to and for example through the scanning zone as a plurality of such datasets of intensity data are collected. In a preferred embodiment, the method comprises detection of transmitted radiation for example for use in generation of a transmission radiograph image. In this embodiment, the method comprises providing a radiation source and a radiation detector system space therefrom to define a scanning zone in a radiation transmission path therebetween, and thereby collecting a dataset of information about transmissivity of an object in the scanning zone. However, the principles of the method can be applied to the collection of information based on other interactions of source radiation and object. The radiation source must produce a distribution of energies across a suitable spectral range for characteristic scattering, and is typically an x-ray source. Tungsten is the most appropriate target, but others could be used. The source may be a single broad spectrum source across which a plurality of bandwidths (which term, as described above, encompasses herein single energies) may be identified. Alternatively or additionally sources may be provided having narrow bandwidths or generating incident radiation at one or more discrete energies to provide some of the energies for comparison in accordance with the method of the invention. In this case the radiation source is a plural source comprising a combination of sources at different energies to provide the necessary total spectrum spread to allow resolution by the detector across a plurality of energies/energy bands. For example a plural source comprises an x-ray source having a relatively lower energy spectrum, for example operating below 60 keV and for example at 10 to 50 keV and one or more radioisotope sources generating radiation at higher energies, for example above 100 keV. Preferably, the method comprises generating an image of an object in the scanning zone, and where applicable a succession of images as the object moves through the scanning zone. In a preferred mode of operation each such image is resolved spectroscopically across a plurality of frequency bands within the spectrum of the source to generate a series of energy-differentiated images. The method of the invention conveniently further provides the additional step of displaying such generated image or images, and in the case of multiple images might involve displaying such images simultaneously or sequentially. In accordance with a preferred embodiment of the invention, each collected image is resolved spectroscopically across a plurality of relatively broad “imaging” bands each intended to generate an image across a broader part of the overall spectrum, so that the imaging bands together allow the generation of an energy-differentiated composite image or succession of images. The number of imaging frequency bands is conveniently between 2 and 10, and for example between 4 and 8. Spectroscopic detectors can be operated in an energy selective manner, giving rise to the ability to present an image resolved into a significantly increased number of “imaging” energy bands compared with the two that are available from standard prior art dual energy detectors. This information can be used to improve resolvability of objects of different composition. This is achieved in accordance with this preferred embodiment in that spectroscopic resolution of transmitted radiation in each such relatively broad band is represented in the generated image. For example, spectroscopic differentiation in the collected data is represented in the image as differentiated colour, shading or marking. A banded mapping is used in that the source spectrum is divided into a plurality of bands, for example between four and eight bands, and different colours are used to represent each such band in the displayed image. The apparatus conveniently includes suitable image processing means to effect this mapping. An image or composite image or succession of images so generated is preferably displayed on a suitable display means. Other preferred features of the method will be understood by analogy with the description of preferred embodiments of the apparatus and its operation. It will be understood generally that a numerical step in the method of the invention can be implemented by a suitable set of machine readable instructions or code. These machine readable instructions may be loaded onto a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a means for implementing the numerical step specified, and in particular thereby to produce a calculation means as herein described. These machine readable instructions may also be stored in a computer readable medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in a computer readable medium produce an article of manufacture including instruction means to implement some or all of the numerical steps in the method of the invention. Computer program instructions may also be loaded onto a computer or other programmable apparatus to produce a machine capable of implementing a computer executed process such that the instructions are executed on the computer or other programmable apparatus providing steps for implementing some or all of the numerical steps in the method of the invention. It will be understood that a step can be implemented by, and a means of the apparatus for performing such a step composed in, any suitable combinations of special purpose hardware and/or computer instructions. Referring first to the general schematic representation on FIG. 1, an x-ray source 1 and laterally spaced detector 3 together define a scanning zone Z between them. The apparatus is configured to detect transmitted x-rays and measure attenuation by absorption. In use, an object to be scanned is brought into and through or placed in the scanning zone in the usual manner, for example on a suitable conveyor belt (not shown). In the illustrated example, a sample of material 9 sits in the scanning zone Z. An incident beam 5 from the x-ray source is illustrated. This is received at the detector 3. The source is adapted to emit an x-ray beam over a wide area. For the purpose of illustration only, three example beam directions are shown representing this area, respectively 5A, 5B and 5C. The detector in the embodiment is a reduced area detector (that is, it covers and differentiates across only a small part of the overall area to be scanned at any given time), and for example resolves to a single pixel only. In the particular illustration, the detector 3 is illustrated in position to collect transmission data from ray path 5C. As part of the raster scanning process, the detector 3 is moved to positions 3′, 3″ to collect data respectively from ray paths 5B and 5A by means of the actuator arm 11 under control of a control means 12. The principles of operation of the control means can be understood with reference to FIG. 2. A raster module within the control means 12 divides a notional imaging area 21 into a plurality of pixels 23 in each of two dimensions. Under control of the control means the detector 3 is moved relatively to the object so as to effect a scan across this area in the direction of the arrows shown. In a simple embodiment, the detector is moved relative to a stationary object and source, but it will be appreciated that any arrangement effecting the necessary relative movement between the rastered image scan area and the detector to enable a scan across the whole image area and to enable a collection of data for each pixel will be sufficient to allow the invention to operate. The precise scanning mode is not directly pertinent to the invention. For example, the image area may be scanned via a simple progressive scan, or via some more complex interlaced scan. The size and pattern of the pixels 23 is a virtual artefact of the rastering process and is determined by the rastering module. In the embodiment, a single pixel detector is used. The spatial resolution of the scan is therefore determined entirely by the virtual resolution created by the raster. In this way, the resolution can be varied between scans for the same apparatus, in that the raster module varies the virtual pixel size 23. A user is enabled to select a desired resolution at the penalty of scan rate. A user might for example select a coarse resolution for an initial scan, and a finer scale resolution for further investigation. Data collected at the detector 3 as it is moved to cover the rastered scan area is passed via a suitable data link to the data processing module 12. The data processing module additionally resolves the information spectroscopically, preferably across at least three separate energy bands. Thus, for each pixel a data set is generated of received intensity data which is spectroscopically resolved. Thus, the overall data set includes both spatial and spectroscopic resolution built up by a simple, effectively one-dimensional detector. In particular, this resolved information is used to generate an image comprising both spatial and spectroscopically resolved information. For example, spatial resolution is represented in two dimensions graphically on the image. Spectroscopic resolution is represented in the image, for example as intensity, with each image being displayed successively, or through some other cue such as colour of hue in a single composite image. Images are displayed on the display apparatus 17. The detector in the preferred embodiment comprises cadmium telluride bulk single crystal. The inherent spectral resolution of the material allows the processor to resolve incident radiation intensity differentially across a plurality of pre-set frequency/energy bands in accordance with the principles of the invention. The source 1 generates x-rays across a relatively broad spectrum of energy, so that this resolution may be exploited. It may be a plural source, or a single source with the necessary spectrum spread. The source 1 is preferably tungsten source. In accordance with the invention, an apparatus and method is described which can offer specific material characterisation based on data which resolved spatially in two dimensions and which resolves that spatial data further spectrally.
	description	FIG. 1 shows a radiation attenuation system 310a providing a radiation drape, pad or shield 312. Shield 312 may be useful in blocking, attenuating and/or reflecting radiation, and assisting in the protection of a worker (e.g. a physician or technologist during a medical procedure) in tasks. Shield 312 may attenuate radiation provided by a variety of natural or man-made sources over a wide range of the electromagnetic spectrum from wavelengths of 1.0xc3x9710xe2x88x9215 meters (e.g. cosmic rays) to 1.0xc3x97106 meters (e.g. radiation from AC power lines) including visible and invisible light, and may find incidental uses at relatively low or high frequency extremes (including gamma rays). Shield 312 may also selectively isolate regions for direction of radiation, and may selectively shroud or protect regions beyond the contours or margin of the zone of interest. Shield 312 may include a radiation attenuation region (shown as a strip 314) for the attenuation of radiation. A fenestration area 316 of shield 312 provides access to an area of interest (e.g. patient) through an aperture (shown as a circular hole 318a and a parallelogram shaped hole 318b) for conducting various invasive procedures, such as the fluoroscopic guidance and/or manipulation of instruments during surgical procedures. Strip 314 may be at least partially surrounded by a panel (shown as a window 320) that is relatively clear or translucent for the viewing of objects (e.g. controls, instruments, etc.) beneath shield 312. Shield 312, strip 314, holes 318a and 318b and window 320 may be of a variety of shapes and sizes, which may be dictated at least in part by the particular application (e.g. angiography, femoral angiography, general biopsy, pacemaker implant, etc.). Indicia 334 for identification or personalization of shield 312 may be identified or written on shield 312. FIG. 2 shows a cross-sectional view of shield 312. The attenuation of radiation is provided by at least a web 322a (e.g. matrix, sheet, film, polymer radiation attenuation material, etc.) of attenuation material or filler, such as barium sulfate powder, bismuth powder, or other attenuating materials/fillers compounded (e.g. mixed, blended, alloyed, etc.) with a polymeric carrier, and a web 322b. On one side of shield 312, web 322a may be attached to a cover 324 such as a fabric (e.g. soft carded polyester) for placement next to the area of interest (e.g. patient). Cover 324 provides some comfort to a user (e.g. patient) and assists in the retention of body heat. On another side of shield 312, an absorbent layer 326 (e.g. polyester) may be coupled to web 322b for maintaining fluid control (e.g. block blood from seeping onto the patient during a surgical procedure). Absorbent layer 326 may include fibers (e.g. wet-laid, spunlaced, etc.) bonded or woven to a reinforcing layer 332 having a network frame or scrim 372 (see FIG. 5). Absorbent layer 326 may be attached to a relatively liquid impervious layer 328a such as plastic, polyethylene, etc. Impervious layer 328a may assist in inhibiting the transmission of fluid from absorbent layer 326 to cover 324 (i.e. separates fluid from the patient). An optional relatively liquid impervious layer 328b may be disposed between web 322a and 322b. A fastener 330 (e.g. adhesive, stitching, spot weld, ultrasonic weld, hot melt, laminate, etc.) may attach the layers of shield 312 (i.e. absorbent layer 326, impervious layers 328a and 328b, webs 322a and 322b, and cover 324) to each other. FIG. 3 shows a radiation attenuation system 310b having a radiation barrier 340. Barrier 340 includes a layer or web 322c including a monolayer (i.e. at least one layer) shown as a primary attenuation layer 322d of a relatively flexible material (e.g. polymer resin). Barrier 340 may be charged with a radiation attenuation material such as metal powder (shown as a particle 342a and a particle 342b). Particle 342a is shown generally evenly distributed and dispersed within layer 322d. A secondary attenuation layer 322e of web 322c is shown attached to layer 322d by a fastener (e.g. hot melt adhesion or laminate). Without intending to be limited to any particular theory, it is believed that multiple attenuation layers may increase the radiation attenuation factor of the radiation attenuation system. Two attenuation layers are shown in FIG. 3, and the radiation attenuation system may have multiple attenuation layers (e.g. 3, 6, 20 layers, etc.) according to alternative embodiments. A tie layer 344 may attach attenuation layer 322c to a covering (shown as a skin 346). The tie layer may include: polyethylenes such as low density polyethylene (LDPE), linear low density polyethylene (LLDPE), very low density polyethylene, very low density polyethylene (VLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE) and metallocene polyethylene (MPE); ethylene copolymers such as ethylene vinyl acetate (EVA), ethylene methacrylate (EMA), ethylene ethylacrylate (EEA) and ethylene butyl acrylate (EBA); acid copolymers such as ethylene methacrylic acid and ethylene acrylic acid; lonomer including zinc and sodium SURLYN film (which may be made of synthetic thermoplastic resin for use in commercial and industrial wrapping) commercially available from E. I. du Pont de Nemours and Company of Wilmington, Del.; extrudable adhesive polymers such as BYNEL adhesive resins (which may be for industrial use) commercially available from E. I. du Pont de Nemours and Company of Wilmington, Del. (maleic anhydride copolymer); thermoplastic elastomers such as styrenic block copolymer, thermoplastic polyurethanes, polyolefin blends, elastomeric alloys, thermoplastic copolyesters and metallocene plastomer; and polypropylenes, etc. Skin 346 may function as a partition or wall to separate attenuation layers 322d and 322e from a user. According to an alternative embodiment, the skin may be made from a material that is the same or different from the material of the attenuation layers, or from a material to enhance processability, softness or comfort for a user. According to another alternative embodiment, the skin may function as a heat-sealing layer. According to other alternative embodiments, the skin may be provided with a colorant (e.g. clear, blue, red, etc.). (The web is typically dark colored, due in part to the color of the attenuation material.) Skin 346 may be attached to a cover layer 348 such as a fabric. One or more of the layers of barrier 340 may be attached or coupled to each other with a fastener. According to other alternative embodiments, the fastener may be omitted. According to still other alternative embodiments, the cover and the absorbent layer may merely surround the web (e.g. as an envelope) and need not necessarily be attached to the web. FIG. 3 also shows the radiation attenuation ability of barrier 340. A primary incident radiation beam 354a is shown having partially penetrated barrier-340. Beam 354a interacts with particle 342a in primary attenuation layer 322d, and is absorbed by particle 342a. Another primary beam 354b is shown having penetrated primary attenuation layer 322d, interacted with particle 342b in secondary attenuation layer 322e, and absorbed by particle 342b. A scattered radiation beam 356 is shown having penetrated primary attenuation layer 322d and absorbed by particle 342a. According to alternative embodiments, primary beams and scattered beams of incident radiation may be attenuated by additional multiple attenuation layers of the barrier or within a monolayer barrier. Multiple layers of radiation attenuation system 310b may cause an increase in the thickness of web 322c, which suitably has a thickness of about 1-300 mil, suitably about 1-50 ml, suitably about 1-10 mil and more suitably about 5-8 mil. (Thus, the total weight of radiation attenuation system may be minimized.) The thickness of the web may also be determined in part by the desired radiation attenuation factor, and the weight and volume requirements of the attenuation material. As shown in FIGS. 4A and 4B, the attenuation material is suitably distributed generally evenly in each of the attenuation layers of a web 322f. Particles 342b are distributed throughout an intermediate film 346b xe2x80x9csandwichedxe2x80x9d or surrounded by a cover film 346a having particles 342a, and a base film 346c having particles 342c. Web 322f may also include layers or films 346d and 346e. Particles 342a, 342b, 342c, 342d and 342e are shown generally evenly dispersed on a dispersion face 350 of each of base film 346a, intermediate film 346b, cover film 346c and films 346d and 346e. On assembly of films 346a, 346b, 346c, 346d and 346e (e.g. as a monolayer laminate), particles 342a, 342b, 342c, 342d and 342e effectively cover the entire surface area of web 322f in an effective coverage area 352, such that substantially all incident radiation will be attenuated by web 322f (see FIG. 4B). The degree of radiation transmission attenuation factor by the radiation attenuation system will depend in part on the specific application to which the radiation attenuation system is put. For example, for medical applications the radiation attenuation system may have a radiation transmission attenuation factor of a percent (%) greater than about 50%, suitably greater than about 90%, suitably greater than about 95%. For other applications, such as articles of clothing, a radiation transmission attenuation factor of a percent of about 10-50%, suitably 10-20% may be sufficient. Any radiation attenuation system may have radiation transmission attenuation greater than at least about a factor of a percent of about 10%, suitably about 10-98%, suitably greater than about 50% (with reference to a 100 kVp x-ray beam). The radiation attenuation system may also at least partially attenuate gamma rays, and may have a gamma ray attenuation fraction of at least about 10% of a 140 keV gamma radiation source. The material of the web is generally light and flexible, to maximize workability for processing, bending, folding, rolling, shipping, etc. The web may be formable (e.g. deformable) or compliant, and relatively xe2x80x9cstretchablexe2x80x9d (e.g. elastic). The shape of the web may be determined in part by the material to which the web is bound. For example, the shape of the web could be relatively planar if bound to a wall, and the shape of the web could be generally curved if bound to a corrugated material. While the resin of the web may partially attenuate some radiation, greater quantities of flexible material in the web may increase flexibility and comfort, and decrease the likelihood of cracking. According to alternative embodiments, the web may be generally rigid and inflexible. Suitable materials for the web include: polyethylenes such as low density polyethylene (LDPE), linear low density polyethylene (LLDPE), very low density polyethylene, very low density polyethylene (VLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE) and metallocene polyethylene (MPE); ethylene copolymers such as ethylene vinyl acetate (EVA), ethylene methacrylate (EMA), ethylene ethylacrylate (EEA) and ethylene butyl acrylate (EBA); acid copolymers such as ethylene methacrylic acid and ethylene acrylic acid; lonomer including zinc and sodium SURLYN film (which may be made of synthetic thermoplastic resin) for use in commercial and industrial wrapping commercially available from E. I. du Pont de Nemours and Company of Wilmington, Del.; extrudable adhesive polymers such as BYNEL adhesive resins which may be for industrial use) commercially available from E. I. du Pont de Nemours and Company of Wilmington, Del. (maleic anhydride copolymer); thermoplastic elastomers such as styrenic block copolymer, thermoplastic polyurethane, polyolefin blends, elastomeric alloys, thermoplastic copolyesters and metallocene plastomer; thermoplastic polyamide (nylon); and polypropylenes, etc. The web may also include synthetic materials such as polyolefins (such as, polypropylene and polybutene), polyesters (such as polyethylene, polyurethane terephthalate and polybutylene terephthalate), polyamides (such as nylon 6 and nylon 66), acrylonitriles, vinyl polymers and vinylidene polymers (such as polyvinyl chloride and polyvinylidene chloride), and modified polymers, alloys, and semi-synthetic materials such as acetate and polytetrafluoroethylene (PTE) fibers. The web may also include a thermoplastic elastomer (e.g. EPM, EPDM, styrene butadiene styrene or SBS, etc.) and others polymer. The attenuation material in the web may assist in the attenuation of incident radiation. The amount of attenuation material may depend in part on the degree of flexibility desired in the web, and the degree of attenuation desired. According to a suitable embodiment, the weight of the attenuation material is greater than the weight of the polymeric resin (e.g. weight ratio), suitably by a ratio of about 10:1, suitably by a ratio of about 5:1, suitably by a ratio of about 2:1, suitably by a ratio of about 1:1. According to another suitable embodiment, the volume of the attenuation material may be less than the volume of the polymeric resin (e.g. volume ratio), suitably by a ratio of about 1:1, suitably by a ratio of about 1:3, suitably by a ratio of about 1:5. According to another suitable embodiment, the volume of the attenuation material may be greater than the volume of the polymeric resin, suitably by a ratio of at least about 10:1. Particularly suitable radiation attenuation materials include barium and bismuth powders, and corresponding salts and oxides (e.g. BaSO4). Other suitable attenuation materials include elements having an atomic number greater than about fifty (50) on the periodic table. Other suitable attenuation materials include barium, bismuth, iodine, tin, tungsten, uranium, zirconium and lead, their corresponding salts or oxides, and combinations thereof. According to a particularly suitable embodiment, the radiation attenuation material does not necessarily contain a significant amount of lead (e.g. essentially free of lead). The size of the radiation attenuation material may in part affect its dispersion within the resin (i.e. relatively larger particles have relatively good dispersion). According to a suitable embodiment, the particles of the attenuation material have a diameter between about 840-10 micron meters (aboutxe2x88x9220 mesh to xe2x88x921250 mesh), suitably between about 297-20 micron meters (about xe2x88x9250 mesh to xe2x88x92625 mesh), suitably between about 149-37 micron meters (about xe2x88x9250 mesh to xe2x88x92400 mesh), suitably between about 74-44 micron meters (about xe2x88x92200 mesh to xe2x88x92325 mesh). According to a particularly preferred embodiment, the barium powder is SPARWITE W-10HB high brightness barium sulfate commercially available from Mountain Minerals Co. Ltd. of Calgary, Alberta, Canada having a median particle diameter of about 1.9-2.1 microns. According to a particularly preferred embodiment, the bismuth powder is commercially available from ASARCO Incorporated of New York, N.Y. Referring to FIG. 5, a web 322g may be a xe2x80x9cfabricxe2x80x9d made from fibers 370 attached (e.g. by hydroentaglement or air laying) to a reinforcing network shown as a scrim 372 having horizontal members 374 interconnected with vertical members 376. The attenuation material may be impregnated in the fiber by a variety of techniques such as fiber spinning process. In the fiber spinning process, a pre-compounded blend is first prepared with relatively fine attenuation powder dispersed within the polymeric matrix (e.g. through a twin screw extrusion). The pre-compounded blend is than fed into an extruder for melt extrusion. The extrudates from the extruder may go through a filter and a xe2x80x9cspinneretxe2x80x9d to form the fiber. The web of the radiation attenuation system, which includes a flexible resin and an attenuation material, may be used in a variety of applications. As shown in FIG. 6, radiation attenuation system 310a may be incorporated into the components of a relatively permanent shelter (shown as a housing unit 382). Housing unit 382 may be useful in situations of generally continuous radiation exposure, and where users would need to stay for long periods. System 310a is shown in a roof 384 to attenuate ambient radiation or radiation from the atmosphere. System 310a may be incorporated into an architectural or construction structure or article such as a wall panel or board 386 or a floor 388. System 310a may be incorporated into an article of furniture such as a partition wall, which may be collapsible (e.g. accordion style folding), or floor covering (shown as a carpet 390) above a basement 380. According to an alternative embodiment, the radiation attenuation system may also be combined with a construction element, such as a concrete floor or wall, a wood board or panel, etc. to xe2x80x9clinexe2x80x9d the construction elements of the building. According to another alternative embodiment, the radiation attenuation system may be used in the insulation of buildings (e.g. to attenuate radon xe2x80x9cgasxe2x80x9d). As shown in FIG. 7, radiation attenuation system 310a may be incorporated into the components of a relatively temporary shelter (shown as a tent 400). Tent 400 may be useful in situations of generally temporary radiation exposure such as an area where there has been an atomic or nuclear explosion or accident. Wall 402 and floor 404 of tent 400 may be lined with system 310a to substantially shield the occupant from radiation. According to an alternative embodiment, the radiation attenuation system may be attached to a more permanent shelter such as a temporary building, housing unit or work environment. As shown in FIG. 8, radiation attenuation system 310a may be incorporated into a garment or article of clothing. The article of clothing may be useful in situations of generally temporary radiation exposure such as an area where there has been an atomic or nuclear explosion or accident, health care areas, etc. The article of clothing could extend the work time of the user in an area, and provide a relatively suitable level of protection against radiation. The article of clothing could also be useful by space travelers working in space exploration to attenuate electromagnetic radiation from outer space. This could be in the form of radiation protection clothing or other radiation protection system forms. As shown in FIG. 8, the article of clothing (shown as a suit 420) includes a head cover 422 (e.g. hood, hat, mask, eye protector, glasses, goggles, etc.), a body cover 426 (e.g. coat, jacket, tunic, shirt), a leg cover 428 (e.g. leggings, pants, coveralls, bibs, etc.), a foot cover 430 (e.g. shoes, shoe cover, boot, etc.) and a hand cover 432 (e.g. gloves, mittens, etc.) each incorporating radiation attenuation system 310a. As shown in FIG. 9A, radiation attenuation system 310a may be incorporated in a sheet of material (shown as a blanket 410). Blanket 410 is shown wrapped around a storage container or water cooler 412 (e.g. in a work environment such as a nuclear reactor plant or atomic/nuclear waste management sites) to attenuate relatively low level radiation. According to an alternative embodiment, the blanket could be used as a xe2x80x9cspace blanketxe2x80x9d to cover areas emitting radiation at relatively low levels. According to other alternative embodiments, the blanket could be used as a part of the walls or wall partitions that typically protect workers who are outside a workspace (e.g. medical cath lab, special procedures lab, etc.). According to other alternative embodiments, the blanket could be used to cover equipment or personnel during space travel and to attenuate electromagnetic radiation from outer space. According to an alternative embodiment, the blanket may be a full drape, so that a worker (e.g. physician or technologist) could relatively quickly and easily roll out the drape and the radiation protection would already be in place (i.e. web could be a part of the entire drape). According to other alternative embodiments, the radiation attenuation system (i.e. web of radiation attenuation material) may be incorporated in a drape of the following types: angiography, femoral angiography, pain management, general or specialized biopsy, TIPS/IJ, dialysis shunt implant, pacemaker implant, radium implant, vascular surgery, etc. According to an alternative embodiment, a femoral angiography shield may have a length greater than its width (e.g. corresponding to a leg), and may include a relatively long aperture for access to the area of interest (e.g. femoral artery). According to still other alternative embodiments, the radiation attenuation system or the web may replace the plastic or fluid impervious layer in conventional drapes such as model No. 44207-0 or 48433-0 xe2x80x9cUniversalxe2x80x9d angiography drapes commercially from Deka Medical, Inc. of Tyler, Tex. As shown in FIG. 9B, radiation attenuation system 310a may be incorporated into a generally rigid container 440. Container 440 may be useful for housing and attenuating radiation from relatively high energy radiopharmaceuticals (e.g. radioactive seeds or implants) that may be used in nuclear medicine procedures (e.g. treatment of brain tumors). Container 440 includes a circular wall 442 (which may be threaded) between a removable cover or cap 444 and a fixed base 446. The radiation attenuation system may be used in medical applications by physicians and other healthcare workers (e.g. interventional cardiologists and radiologists, pain management physicians, radiation therapy/oncologists, electophysiologists, etc.) who may work with fluoroscopy or in nuclear medicine. The radiation attenuation system (i.e. the web of having the attenuation material) may be configured and incorporated in any number of convenient shapes and sizes such as: radiation protection pads, thyroid shields, male gonadal shields, female gonadal shields, diapers, aprons (including miniaprons), breast shields, scoliosis shields, gloves, eye disks, barriers, and infant stabilization/shield members, shields, markers, table pads and density wedges. Such articles may be relatively easily trimmed to shape or fit to the extent necessary or desirable. Exemplary articles of the radiation attenuation shield are shown in FIGS. 10A through FIG. 10Y. FIG. 10A shows a radiation pad 10. Pad 10 is comprised of a panel 12 shown in the form of a rectilinear slab. Pads such as the radiation pad 10 are typically placed over an area of a user (e.g. patient) to be examined with a central cut or tapered aperture 14 defining the region within which the worker (e.g. examiner) will be working on the user. Aperture 14 may be placed coincident with the primary x-ray beam. The tapering presents a convenient field within which to work and to provide an edge, which will reside closely in contact with the body of the user. The radiation attenuating material from which the web is intended to at least partially attenuate radiation near the worker (e.g. physician) as he works on a patient. Such shields assist in the protection of the hands, arms, face and eyes of the worker when working close to a primary x-ray beam, preventing such debilitating or unwanted effects as the development of radiation-induced arthritis, dermatitis or hair loss. This can be a consideration whether the radiation is associated with a mammography, having a primary beam less than about 20 kVp as is for relatively high energy, and relatively high resolution work with beams over about 120 kVp. Further, in some nuclear medicine applications, medical workers may require a radiation attenuation system that can attenuate gamma rays and radiation levels of at least about 140 keV. Shields can be tailored for use throughout this energy range and are conveniently adaptable for use beyond it. FIG. 10B shows a thyroid shield 20. Shield 20 may be comprised of a body of radiation attenuating material 22 bearing a cloth or other type of covering 24 to improve comfort. The thyroid shield includes opposed ends 26, which provide an attachment member, such as that known as Velcro, to facilitate attachment of the thyroid shield to a user (e.g. patient). FIGS. 10C and 10D illustrate male and female gonadal shields 30 and 40 (respectively). These shields are configured to protect the gonadal region of a user (e.g. patient) during a radiological procedure. FIG. 10E is a view of a diaper 50 having a fastener 52 and 54 at opposed upper edges to facilitate the disposition of such a diaper about a user (e.g. patient). Diaper 50 may be made in a range of sizes to fit adult or adolescent patients as well as infants, to protect the gonadal and abdominal regions of the patient during a radiological procedure. FIGS. 10F and 10G show full torso protective aprons designated 60 and 62, respectively. Torso apron 60 is comprised of an enveloping shroud or apron 64 that encircles the front and back of the body of the wearer. Opposed marginal edges meet at a juncture 65, which is secured by fasteners 66. If desired, the body of apron 60 may be covered with a cloth, cloth-like material, or other types of material to improve wearer comfort and to place and secure fasteners 66. Body panel 67 of apron 62 drapes only the frontal portion of the wearer. In this instance, apron 62 does not surround the torso. It is secured to the wearer by ties or straps 68 encircling the waist region. A miniapron 70 is shown in FIG. 10H. Miniapron 70 is comprised of a body or panel region 72 suspended from the waist of a wearer by ties or a fastening member 74. Miniapron 70 covers only a portion of the lower torso of the wearer. The apron designs of FIGS. 10F and 10G and 10H are configured to provide both examiner/patient comfort and examiner/patient safety in connection with radiological procedures or other exposure to sources of radiation. FIG. 10I shows a breast protective barrier drape or shield 80 worn by a user (e.g. female patient), for example during a mammographic x-ray procedure. Breast shield 80 is thus comprised of an upper shield 82 which protects the portion of the anatomy of the user that is not subjected to examination, and shield 82 extends downwardly from the body of the user (e.g. from the shoulder toward the abdomen). A further shielding element 84 is provided about the gonadal region of the user (e.g. patient) to protect those organs as well. Accordingly, only the area to be examined is presented for irradiation while surrounding regions are protected against unwanted exposure. FIG. 10J shows a scoliosis shield 90. Shield 90 drapes from the shoulder region of the user (e.g. patient) to the lower abdomen. Shield 90 further includes a gonadal shield 92. The scoliosis shield leaves an exposed region 94 for examination. FIG. 10K shows a protective glove designated generally as 100 fabricated from radiation shielding material. Glove 100 may be used by a health care practitioner when manipulating instruments or tools proximate a primary beam or in a region of secondary or scattered radiation; it may be worn by a user (e.g. patient) to protect his or her hand during examination of the body of the user in regions next to such a radiation source; or the glove may be worn by an individual who is required to handle sources of radioactive material. FIG. 10L shows a perspective view of a user (e.g. patient) wearing a protective eye disc 110. The user is shown supported on an examination table 112 above a photographic plate 114, positioned for irradiation by an x-ray tube 116 to provide an x-ray image of the head and/or neck region of the user. In this instance, the eye protection assists in safeguarding the optical anatomy of the user from unwanted or undesirable exposure to the primary beam. The shield may also be useful in xe2x80x9ctanning rooms.xe2x80x9d FIG. 10M shows protective barriers and shields 120 and 122 used to protect personnel in an x-ray examination room or the like. In this instance, barrier 120 is associated with an examination table 123 placed beneath the tube of an x-ray machine 124. When a user (e.g. patient) is examined on table 123, drape or shield 120 confines scattered radiation from beneath the table. Also, during fluoroscopic procedures with the x-ray tube underneath the table, the drape or shield 120 could confine the scattered radiation underneath the table and attenuate radiation to at least partially protect the examining attendant and patient. Shield 120 may envelop the entirety of examination table 123 or be placed only on the side or sides toward which the examining attendant faces. This may be in a form similar to a xe2x80x9ctable skirtxe2x80x9d that extends to the floor. Barrier 122 protects that attendant, as also shown in FIG. 10M, as well. In this case, the shield is formed with a cut-out or visually transparent component 125 through which the worker (e.g. examiner) may observe the patient. A certain amount of radiation may be transmitted through region 125. Barriers of the sort shown in FIG. 10M can be of assistance in establishing either remote or temporary x-ray facilities. Most x-ray rooms include lead lining in or on the walls to confine radiation and prevent stray radiation from leaving the region of the x-ray apparatus. It is not always convenient or desirable to provide that type of lead-circumscribed environment, in which case protective barriers are capable of providing temporary but nonetheless relatively efficient shielding. Barriers of the sort shown in FIG. 10M, but modified appropriately, may also be useful in space travel to line the walls of a space vehicle or space station to attenuate electromagnetic radiation from outer space. FIGS. 10N and 10O show a protective drape, in this instance configured for a cardiac catheterization procedure to be performed on a user (e.g. patient). A protective drape 130, is sized to cover the user essentially over the majority of the body, being draped from the upper chest region to the lower legs as best viewed in FIG. 10N. Drape 130 could be of sufficient width to span entirely across the user (e.g. patient) and the operating table. Drape 130 is fabricated from radiation shield. A first keyway or cut-out 132 is formed in the upper thigh region while a panel or window 134 of neutral material is provided in the drape in the region of the heart of the user. The cut-out provides the worker (e.g. physician) with an entry point to insert a needle or through which to introduce the catheter instrumentation. The patient is subjected to x-ray radiation passing through the region of window 134. Watching an appropriate display responsive to that radiation, the worker may manipulate the catheter from the region of cut-out 132 into proper position proximate the heart. During that procedure, however, protective drape 130 at least partially protects operating room personnel from scattered radiation. The compliant nature of drape 130 allows it to reside closely next to the body of the patient. It is comfortable and fits positively against the undulating surface of the patient, thus improving its stability while the surgical team is operating on the body of the patient. The coefficient of friction between the drape and the skin of the patient adds to that stability, preventing movement of the drape during the surgical procedure and further obviating the need to take extraordinary measures to prevent slippage or movement of the drape. FIG. 10P shows a radionuclide transportation and storage article or device 150. In this instance, device 150 is comprised of a body of radiation attenuating material having a plurality of blind apertures 154 formed therein. Each of the apertures 154 is dimensioned to receive a vial of radioactive material to be transported and/or stored (e.g. material used in radiation treatment in a hospital). Each of blind apertures 154 may be slightly undersized to ensure a close interference fit between body 152 and the vials to be inserted in those apertures. Once in place, a cover of similar material may be disposed over device 150 and secured in any convenient manner for transport and/or storage. FIG. 10Q shows a marker 160 placed on a user (e.g. patient) undergoing radiological examination. Marker 160 is positioned at a specific location on the body of the patient to provide a benchmark for measurement on the image resulting from the x-ray procedure. Thus, being radiopaque, a mark will appear either on an x-ray film or on a real time display permitting a worker (e.g. physician) to measure with reasonable precision the location of internal anatomy from that known point as evidenced by the marker. FIGS. 10R and 10S show film markers such as have been used in the past to identify x-ray films. In each case, a marker 170 is comprised of a support 172 bearing a letter indicia 174 either as an xe2x80x9cRxe2x80x9d or as an xe2x80x9cL.xe2x80x9d These indicia are meant to identify radiographic representations as either the right or left part or extremity of some anatomical element or, if the object being examined is not a patient but an inanimate object, other markers of similar variety may be used to identify specific locations or characteristics. Typically, the support will be radio-transmissive whereas the indicia will be radiopaque. Where such markers are utilized with patients in x-ray examination and especially where the marker is placed in contact with the patient, the marker may then be disposed. FIG. 10T shows an infant stabilization device including a protective radiological shield 180. Shield 180 includes a frame 182 having a plurality of straps 184 (or the like) for restraining the infant in position on the stabilization member. A border 186 of radiation attenuating material is disposed peripherally about the stabilization member while the infant may be provided with a diaper 187 likewise made from radiation attenuating material in accordance with the present invention. A cut-out region 188 is provided to allow x-ray examination of the infant or a selected portion of his anatomy. Typically, the infant is placed on the pad and is strapped into position with his hands suitably secured. With shielding in place, a holder such as the parent of the infant (also suitably protected) may assist in the x-ray procedure as required. FIGS. 10U, 10V and 10W show different forms of patient positioning devices used in radiological procedures, either investigative or therapeutic. In FIG. 10U, the hand of a patient is positioned on a positioning device 190; in FIG. 10V, the leg of the patient is confined within a positioning device 192; and in FIG. 10W, the head of the patient is suitably positioned within a device 194. FIG. 10X shows a fluoroscopic table pad 200. Table pad 200 is of a generally rectilinear configuration, shaped as a web 202 fabricated from a one-quarter inch to one-half inch slab of radiation attenuating material in accordance with the present invention. Zones of neutral material 204 are formed in the pad 200, here disposed in shape and size as required for angiography. Cut-outs 206 in the pad allow items to be inserted through the pad as may be required. The pad is placed on the table beneath a patient undergoing angiography, during which he is subjected to x-ray radiation from beneath the table. The primary beam is allowed to pass through the pad only in the regions of the neutral material 204. FIG. 10Y shows a pair of density wedges 210. Each of wedges 210 is tapered and thus provides higher density radiopacity at the thicker edge than at the thinner or tapered edge. According to alternative embodiments, the radiation attenuation system may be used in space travel or shelter (e.g. space station or vehicle) applications. Specifically, the system may substantially protect humans or sensitive cargo from radiation that could be present in outer space. According to other alternative embodiments, the radiation attenuation system may have applications in the medical, industrial, clothing, architectural (e.g. furnishings and wall coverings), packaging and shipping containers (e.g. food, electronics, etc.), construction materials, geotextiles, and vehicular (automotive, boating, airplane, exterior and interior) industries. According to a preferred embodiment, the radiation attenuation system is generally disposable in whole or in part, thereby minimizing ancillary sources of contamination that may arise from multiple uses. According to another suitable embodiment, the radiation attenuation system is generally non-toxic, recyclable, and/or biodegradable. According to an alternative embodiment, the radiation attenuation system may be reusable (e.g. for attenuation of radiation from atomic/nuclear disaster, clean up, rescue operations, etc.). According to a preferred embodiment, the radiation attenuation system may be sterilized between uses to minimize the likelihood of bacteriological or virus contamination. Sterilization may be performed in any convenient manner, including gas sterilization and irradiation sterilization. The xe2x80x9cdurometerxe2x80x9d is a suitable measure of the drape and hand of the radiation attenuation system. For certain applications such as a medical drape, the durometer of the system is suitably less than about 100 Shore xe2x80x9c00, xe2x80x9d suitably about 5-80 Shore xe2x80x9c00xe2x80x9d, suitably about 15-40 Shore xe2x80x9c00. xe2x80x9d Shore xe2x80x9c00xe2x80x9dmay be measured on a Shore durometer commercially available from Shore Manufacturing Company of Jamaica, N.Y. The selection of materials for the radiation attenuation system that yield an appropriate softness (which manifests itself in terms of hand and drape viewed in the apparel context) provides a material that is relatively conformable to the body (e.g. patient) or article shrouded. The xe2x80x9ccoefficient of sliding frictionxe2x80x9d (determined as the tangent of the angle of inclination to induce sliding) relative to the body (e.g. patient) or article shrouded is a suitable measure of the friction provided by the radiation attenuation system. The coefficient of friction between the radiation attenuation system and the skin of the user (e.g. patient) may add stability, thereby preventing movement of the radiation attenuation system during use (e.g. the surgical procedure) and further obviating the need to take extraordinary measures to prevent slippage or movement of the radiation attenuation system. The coefficient of sliding friction of the radiation attenuation system is suitably sufficient to maximize the placement stability of the radiation attenuation system when in use, and is sufficiently great enough so that the radiation attenuation system cannot be easily dislodged or moved after placement for certain applications. For other certain applications such as a medical drape, the coefficient of sliding friction of the radiation attenuation system is suitably at least about 0.15, suitably at least about 0.5, suitably at least about 0.75, suitably at least about 1.0. For specific applications such as a surgical drape or protective shield for direct contact with a user (e.g. patient), the coefficient of sliding friction of the radiation attenuation system is suitably at least about 2.0. FIG. 12 shows exemplary process steps for making the radiation attenuation system according to a three layer coextrusion blown film polymer process method. (According to an exemplary embodiment as shown in FIG. 13, three extruders may be used to manufacture an xe2x80x9cABAxe2x80x9d or three layer structure, with each xe2x80x9cAxe2x80x9d layer being a skin layer and the xe2x80x9cBxe2x80x9d or intermediate layer being a radiation attenuation layer.) FIG. 13 shows an apparatus 464 for manufacturing an exemplary radiation attenuation system. Referring to FIGS. 12 and 13, the radiation attenuation material (i.e. powder) is mixed (step 448) in a blender or mixer 466, and then compounded (step 450) in a compounder 468 (such as a twin screw extruder) and then xe2x80x9cpelletizedxe2x80x9d or cut into attenuation pieces or pellets 470 (step 452). Pellets 470 are fed into a hopper 498 and melted (step 454) e.g. in a melt process. The resulting melt may be pumped or extruded (step 456) from an extruder (shown as extruders 472a, 472b and 472c) through a forming die 482. The resulting extrusion is formed (e.g. xe2x80x9cblown,xe2x80x9d inflated or filled with air) (step 460) to produce an extrusion or xe2x80x9cbubblexe2x80x9d 484. Each of the extrusions from each of extruders 472a, 472b and 472c can provide a layer of material to bubble 484. (Three layers of bubble 484 are shown in FIG. 13. According to an alternative embodiment, one or more layers may be formed according to the number of layers desired in the bubble.) An air ring 480 may blow cooled or chilled air to cool and stabilize bubble 484 (step 460). As shown in FIG. 13, an air valve 478 may manipulate the air. According to alternative embodiments, the bubble may be of a variety of shapes such as a film, sheet, bottle, etc. depending on the application. Bubble 484 may be pulled by a nip 488, and collapsed by a wall or frame 486 to form a sheet of a relatively flat web 496 (step 462). Web 496 may travel through a set of nips and a number idler rolls 490. According to alternative embodiments, the web may be further processed (e.g. lamination, die cut, finishing, etc.) depending on the application. According to another alternative embodiment as shown in FIG. 13, web 496 may be corona treated by a corona device 492 depending on the final application. Web 496 may be wound in a roll 494 for storage or shipping. According to alternative embodiments, the radiation attenuation system may be made according to a variety of polymer process methods, including but not limit to, cast film/sheet process, tubular blown film process, cast sheeting process, sheet calendaring, fiber spinning, blow molding, injection molding, rotational molding, foam process and compression, transfer molding, profile extrusion and coextrusion, non-woven process, etc. The radiation attenuation percent (%) of an incident direct radiation beam by a radiation attenuation system was measured. For EXAMPLES 1-3, the results were obtained with a Keithley 35050A Dosimeter with a 15 cc chamber commercially available from Keithley Instruments, Inc. Radiation Measurements Division of Solon, Ohio. A radiation attenuation sample was prepared. The sample included a radiation attenuation material of bismuth oxide powder commercially available from ASARCO Incorporated of New York, N.Y. and barium sulfate powder commercially available from Mountain Minerals Co. Ltd. of Calgary, Alberta, Canada and having a weight ratio of 22:78. The resin was a model no. PE 1031 low density polyethylene resin (commercially available from Huntsman Corporation of Salt Lake City, Utah) having a density of 0.924 gram per cubic centimeter and a melt index of 0.8 gram per 10 minutes. The weight of the radiation attenuation material to resin polymer material was about 2.3:1. The volume of the radiation attenuation material to resin polymer material was about 1:4. The sample was die cut into three pieces resulting in Samples 1, 2 and 3. Sample 1 was one layer of the die cut sample. Sample 2 was two layers of the die cut sample (one piece on top of the other). Sample 3 was three layers of the die cut sample (each piece on top of the other). The radiation attenuation percent of the Samples are shown in TABLE 1. A radiation attenuation sample was prepared. The sample included a radiation attenuation material of bismuth powder commercially available from ASARCO Incorporated of New York, N.Y. and barium sulfate powder commercially available from Mountain Minerals Co. Ltd. of Calgary, Alberta, Canada and having a weight ratio of 22:78. The resin was a model no. PE 1031 low density polyethylene resin (commercially available from Huntsman Corporation of Salt Lake City, Utah) having a density of 0.924 gram per cubic centimeter and a melt index of 0.8 gram per 10 minutes. The weight of the radiation attenuation material to resin polymer material was about 1:1. The volume of the radiation attenuation material to resin polymer material was about 1:9. The sample was die cut into three pieces resulting in Samples 1, 2 an 3. Sample 1 was one layer of the die cut sample. Sample 2 was two layers of the die cut sample (one piece on top of the other). Sample 3 was three layers of the die cut sample (each piece on top of the other). The radiation attenuation percent of the Samples are shown in TABLE 2. At 90 kVp, Sample 1 had about a 10% attenuation factor, and Samples 2 and 3 had about a 20% and 30% attenuation factor (respectively). With the loading of attenuation materials in the samples, the effect was about 10% radiation blocking per layer of material. Higher levels of attenuation may be achieved as the compounding material loading is changed, and multiple layers of material are used. A radiation attenuation sample was prepared. The sample included a radiation attenuation material of bismuth powder commercially available from ASARCO Incorporated of New York, N.Y. and barium sulfate powder commercially available from Mountain Minerals Co. Ltd. of Calgary, Alberta, Canada and having a weight ratio of 22:78. The resin was a model no. PE 1031 low density polyethylene resin (commercially available from Huntsman Corporation of Salt Lake City, Utah) having a density of 0.924 gram per cubic centimeter and a melt index of 0.8 gram per 10 minutes. The weight of the radiation attenuation material to resin polymer material was about 2.3:1. The volume of the radiation attenuation material to resin polymer material was about 1:4. The sample was die cut into four pieces resulting in Samples 1, 2, 3 and 4. Sample 1 was one layer of the die cut sample. Sample 2 was two layers of the die cut sample (one piece on top of the other). Sample 3 was three layers of the die cut sample (each piece on top of the other). Sample 4 was four layers of the die cut sample (each piece on top of the other). The radiation attenuation percent of the Samples are shown in TABLE 3. The radiation system may at least partially xe2x80x9cshieldxe2x80x9d or attenuate radiation from a gamma radiation source (e.g. gamma-ray). A gamma ray is believed to be made up of photons or small bits of light traveling as waves of energy. Gamma-rays are an example of relatively high energy photons, and are part of the electromagnetic spectrum. The energy carried by photons is typically measured in units of electron volts (eV). For example, visible light is made up of photons with energies of about 2 or 3 eV, and gamma-rays are photons of light with energies of 50,000 eV (50 keV) to 1,000,000,000,000 eV (1 TeV) or higher. One measure of the shielding of gamma radiation is the attenuation coefficient of a material. The attenuation coefficient shows the ability of the material to xe2x80x9cshieldxe2x80x9d or attenuate gamma rays of a particular energy. The attenuation coefficient may include the measure of the slope of the natural logarithm of the intensity of the gamma radiation plotted against the thickness of the material. Shielding may occur when incident radiation is either reflected or absorbed by a material. Linear density and composition of a material also may affect its ability to shield gamma radiation. The energy of the gamma ray may affect the amount and the means by which it is shielded. Relatively lower energy gamma rays are believed to undergo the photoelectric effect or Compton scattering, while higher energy photons are believed to collide with atoms to produce electron-positron pairs. Density (or ration of attenuation material to the carrier of the attenuation material) is also related to shielding ability. The radiation attenuation fraction of a relatively high energy radiation beam by a radiation attenuation system may be measured as shown in prophetic EXAMPLE 4. A radiation attenuation sample may be prepare prepared. The sample may include a radiation attenuation material of bismuth powder commercially available from ASARCO Incorporated of New York, N.Y. compounded in a polymer resin. The weight of the radiation attenuation material to polymer resin may be varied for each sample. Each sample may be tested against both Technetium-99 (with energy level of 140 keV) and Iodine-131 (with energy level of 365 keV) which emits gamma radiation. The attenuation fraction of each sample is shown in TABLE 4. The construction and arrangement of the elements of the radiation attenuation system as shown in the preferred and other exemplary embodiments is illustrative only. Although only a few embodiments of the present inventions have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g. variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited in the claims. For example, the attenuation material may be embedded in the web. The radiation attenuation system may be of a variety of sizes (e.g. 125xe2x80x3xc3x9775xe2x80x3, 32xe2x80x3xc3x9734xe2x80x3, 32xe2x80x3xc3x97110xe2x80x3, etc.). The web may be a relatively fluid impervious layer. Accordingly, all such modifications are intended to be included within the scope of the present invention as defined in the appended claims. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. In the claims, any means-plus-function clause is intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the preferred and other exemplary embodiments without departing from the spirit of the present inventions as expressed in the appended claims.
	description	Not Applicable Not Applicable Radioactive waste has been buried in Vertical Pipe Units (VPU's) at various locations around the planet in many countries. The VPU's are hollow cylinders that are usually the length of five 55 gallon containers app. 15 feet long and 22 inches in diameter. In order to bury the VPU an excavation was prepared to the depth required and the VPU was set in the soil usually on a concrete footing or base. The VPU was then filled with smaller containers, such as vials and jars containing radio-active and non-radio active chemicals that may be liquid in nature. These VPU's are buried at known locations. The condition of the VPU's is unknown. Most of them were buried in the 1950's and corrosion could have damaged the steel walls of the VPU's. There is the present danger that after many years of burial the integrity of the VPU's is compromised such as these chemicals may leach out and contaminate the soil and get into the ground water. Presently an effective method to remediate and safely dispose of such waste does not exist. Remediation is the process of making a burial site non-toxic by the safe removal of the contents and back filling with fresh soil. Stabilization is the process of allowing the dangerous chemicals to react and mix with the soil thereby rendering them less dangerous to handle. In order to dispose of the waste buried in VPU's it is not safe to attempt to remove the buried VPU as a single unit because of the risk of leakage during removal. Furthermore, there is a need to have the capability of identifying the hazardous or non hazardous nature of the VPU contents because the method of disposal in each case will be different. The VPU contents get mixed with the surrounding soil. This process is completely contained within the enclosure provided by the apparatus used. The grinding of the VPU exposes the chemicals and allows chemical reactions to occur between the reactive chemicals stored in the VPU. This in-situ stabilization of contents makes it safer to remove and dispose. The chemical and soil mixture can be analyzed by various non destructive assay (NDA) methodologies and a continued determination made as to the hazardous nature of the mixed contents. This is determined by the measurement of radio activity to characterize the contents as to whether it is Transuranic (TRU) or not. U.S. Pat. No. 7,381,010 to Alexander et al 2008 Jun. 3 that showed a system and method of removal of buried objects did not resolve the stabilization and identification of the waste as shown in the embodiments described below. The aspects described below also addresses the in-situ stabilization of the hazardous contents that was not addressed by the Alexander patent. The advantages listed below are for one or more aspects. The aspects discussed below efficiently render any VPU and its contents into a well mixed waste stream with no visible discrete objects (i.e anomalies) in a manner that is safe for workers; safe for the environment, meets applicable environmental regulations and does not expose identifiable waste objects to the atmosphere. Furthermore, the waste is efficiently removed from the waste site. It is characterized with respect to transuranic (TRU) isotope concentration. Waste is characterized with respect to waste acceptance criteria. Specially designated waste disposal facilities exist in the USA for TRU waste and non TRU waste. Thus several advantages of one or more aspects are that the containers are punctured and the waste mixed with the soil. This technique allows the chemicals contained in the waste to react with each other thereby reducing the reactivity of the chemicals. The waste is mixed with the soil and in one or more aspects in situ measurement of radiation is done to characterize the waste in terms of its radioactivity. This process of grinding of the contents of the VPU with the soil leads to stabilization of the waste. A NDA is conducted in-situ to categorize the radioactivity of the waste. Optical inspection of the waste in one aspect provides a visual record of the stabilized waste prior to disposal. The aspects also show the system and safe removal of the waste/soil mixture depending on the category of the mixture based on its radioactive level without danger of emission or leakage into the environment. The mixing with the soil allows the liquids to be absorbed and the waste will not have free liquids that are prohibited to be present in the waste regardless of whether they are radioactive or non hazardous liquids. These and other advantages of one or more aspects will become apparent from consideration of the ensuing description and accompanying drawings. The aspects describe a system and method for the stabilization and safe removal of the contents of buried VPU's that contain TRU as well as non TRU waste. In one aspect a crane with a vibratory hammer is used to lift and insert a four foot diameter; ½ inch thick carbon steel spiral 25 feet in length casing over the buried VPU. An enclosure base (EB) is used to align the casing over the VPU. The vibratory hammer sinks the casing to a depth of approximately 22 feet and the over-casing extends approximately 5 feet below the bottom of the VPU providing an enclosure that surrounds the buried VPU. The next stage of the process is to introduce a grinding tool such as an auger to grind and shred the contents in order to reduce the size of the contents and mix intimately with the surrounding soil. The apparatus used has sealing parts to ensure that no dust escapes outside the over casing or into the atmosphere during the grinding process. The contents of the VPU are ground to reduce the size to approximately 0.5 inches in to around 3.0 inches dimensions in random particle shapes that get mixed with the surrounding soil. This mixing process exposes the chemicals that are stored in the VPU and allows reactions to occur. The main concern is for sodium potassium (NaK) and/or its super oxides that were used in nuclear reactors as a cooling medium. The breaking of the containers stored in the VPU will release chemicals and free liquids for reactions to occur. These chemicals react violently with each other in the presence of oxygen or water and are rendered less harmful. Furthermore, free liquids will mix with the soil and get absorbed. The VPU contents get mixed with the surrounding soil. This process is completely contained within the casing provided by the system used. The chemical and soil mixture is analyzed by non destructive assay (NDA) methodologies the radioactivity level of the mixed materials is determined and the waste is characterized as being TRU waste or non TRU waste. The threshold of radio activity for this determination is 100 nanocuries (nCi)/gm. If it is determined that the mixture is not TRU then one or more retrieval and disposal methods related to non hazardous material is used. If it is determined that the mixture is TRU waste then a different method for retrieval and disposal is used. In situ NDA methods are shown in the different aspects The NDA can also be conducted in an outside laboratory if required. Based on the radioactivity level different techniques are used. TRU waste is retrieved without further treatment using methods that prevent any leakage. In one aspect a retrieval enclosure (RE) is used. A video record of the waste stream is made in one aspect prior to packing in new 55 gallon drums. For non TRU waste grout is introduced and the waste mixed with the grout. This grout is allowed to set such that a monolith is formed. This VPU monolith is removed and placed in a previously dug trench for safe removal. For TRU waste in one aspect a retrieval bucket is used to retrieve the stabilized contents. A video recording may be made of the mixture contents prior to storage of the contents in new 55 gallon drums for safe disposal. A second aspect introduces a grouting mixture via a grouting tool that replaces the auger such that a fixative type grout can be introduced through the grouting tool into the waste/soil mixture. The fixative grout is commercially available and well known in the art. It reduces the formation of dust by wetting the contents and the waste can be removed without creating hazardous dust. Non TRU waste can similarly be mixed with a standard setting type grout. This grout is allowed to cure such that a monolith or column of the contents and grout is created and the entire column can be removed and disposed off in trenches. The various embodiments and aspects in the summary are described in detail in the following description along with the drawings listed below. In the drawings identical reference numerals denote the same elements throughout the various views. 6 Soil 8 Casing 9 Stabilized mixture 10 Vertical Pipe Unit (VPU) 18 Enclosure Base (EB) 20 Alignment pins 24 Interface Enclosure (IE) 26 Auger Tool Enclosure (ATE) 28 Tool Enclosure door 30 Air sampling port 34 Safety shut down door 36 Seals 38 Attachment for high pressure water 39 Attachment for low pressure water 40 Augering tool 42 Hollow Stem Auger (HSA) 44 Hollow Stem 46 Sampling port 48 Drilling rig 49 Kelly Bar 50 Detector 52 Metal Tube 54 Retrieval Enclosure (RE) 56 Retrieval Bucket 58 Retrieval Hopper 60 Conveyor belt 62 55 gallon drums 64 Grout mixture 66 Cement Truck 68 Pump 70 Hose Transuranic waste (TRU) is, as stated by U.S. regulations and independent of state or origin, waste which has been contaminated with alpha emitting transuranic radionuclides possessing half-lives greater than 20 years and in concentrations greater than 100 nano curies (nCi)/gram (3.7 MBq/kg). Elements having atomic numbers greater than that of uranium are called transuranic. It is material that is contaminated with U-233 (and its daughter products), certain isotopes of plutonium, and nuclides with atomic numbers greater than 92 (uranium). It is produced during reprocessing of spent fuel to separate plutonium for use in weapons. These man made elements within TRU are known to contain americium-241 and several isotopes of plutonium. Their radioactivity is generally low, but since they contain several long-lived isotopes, they must be managed separately. Because of the elements' longer half-lives, TRU is disposed of more cautiously than non TRU waste. In the U.S. it is a byproduct of weapons production, nuclear research and power production, and consists of protective gear, tools, residue, debris and other items contaminated with small amounts of radioactive elements (mainly plutonium). The curie (symbol Ci) is a unit of radioactivity named after Marie and Pierre Curie. It is defined as 1 Ci=3.7×1010 decays per second. One Curie is roughly the activity of 1 gram of the radium isotope 226Ra, a substance studied by the Curies. The SI derived unit of radioactivity is the becquerel (Bq), which equates to one decay per second. Therefore: 1 Ci=3.7×1010 Bq=37 GBq. One nano curie is one billionth of one Curie. Nuclear regulatory Commission (NRC) regulatory Guidelines 8.21 and 8.23 define removable surface activity as “radioactivity that can be transferred from a surface to a smear test paper by rubbing with moderate pressure.” FIG. 1 shows the aspect where the casing (8) surrounds the buried VPU (10). The casing is made of ½′ thick carbon steel spirally welded metal pipe about 25 feet in length. The 25 feet length of the casing (8) results in approximately 3 feet remaining over ground level and 22 feet below the ground level to a depth of approximately 5 feet below the bottom of the VPU. The casing (8) is 4 feet in diameter. Alignment pins (20) on an enclosure base (EB) (18) are used to center the casing (8) around the VPU. It can be recognized that the EB (18) can be replaced by attachments on the steel casing that can be used for the purpose of centering and a separate enclosure base may not be necessary. FIG. 2 shows the exploded view of the enclosure assembly consisting of three sub-assemblies. The EB (18) has a plurality of the alignment pins spaced on the base to help align the casing (8) concentrically over the buried VPU (10). The EB (18) is equipped with a safety shutdown door (34). An interface enclosure (IE) (24) is placed and secured over the EB (18) and provides dust control during augering. The IF (24) has an air sampling port (30) for taking air samples for analysis of gases. All the air is exhausted through a passive high efficiency particulate (HEPA) filter (not shown) and into the atmosphere. The HEPA filter technology is well known in the art. Alternate methods know in the art can be used to ensure that the discharged air is environmentally safe. The IE (24) has attachment ports for high pressure, low volume water (38) to clean the augering tool (40) as it is being retracted. (Mechanical devices such as scrapers can also be used for this purpose). It also has attachment ports (39) for low pressure, low volume dust suppression system (Dust Bond™, calcium chloride solution) that is used to reduce dust during augering. The IE (24) is the attachment point for the an augering tool enclosure (ATE) (29) containing the augering tool (40) or a hollow stem auger (HSA) (42) (FIG. 4) that has a hollow stem in the axial direction. (44). (As will be seen later two augering tool enclosures are provided, one housing the augering tool and the other housing the hollow stem auger). The ATE (26) has a tool enclosure door (28). This door is kept closed for safe removal of the ATE (26) containing the augering tool (40). The ATE (26) is provided with a sampling port (46) for testing surface contamination on the augering tool (40) using the “smear test” that is well known in the art. Seals (36) seal the augering tool shaft and the rotational shaft also known as the Kelly bar (49) to prevent any contaminated air or dust escaping into the atmosphere. It is possible to provide one single unit (52) that combines the features of the IE (24) and ATE (26). It can be provided with the same features for cleaning, sampling and clean venting through the HEPA filters as is provided with having three separate units. The drilling rig (48) attaches its rotational shaft also known as a Kelly bar (49) to the auger shaft protruding through the top of the ATE. (FIG. 8). The drilling rig is used to move the ATE (26) containing the augering tool (40) into position over the IE (24) and is attached to it using conventional attachment methods. The augering tool (40) has a diameter of app. 46 inches to provide a small clearance as it is inserted into the casing. By its rotation it punctures the VPU (10) wall, grinds the contents of the VPU (10) and mixes it with the surrounding soil (6). The stabilized mixture (9) shown in FIGS. 7 and 8 is tested and retrieved using methods shown in the Operation section below. The retrieval method is dependent on whether the stabilized mixture (9) tests as TRU or non TRU waste. FIG. 4 shows the sectional view of the HSA (42) that serves a dual purpose in the system. It is used as a grouting tool to insert grout and create a monolith for the removal of certain types of waste such as non TRU waste. The HSA (42) is also use to introduce a fixative grout to reduce dust in case of TRU waste. It is also used in one aspect for introducing a radio active measuring device as shown in FIG. 5 for in-situ non destructive assay (NDA) of the ground mixture The HSA (42) has a diameter of approximately 14 inches and an cylindrical stem diameter of approximately 4 to 6 inches. The HSA (42) is housed in a second ATE (26) identical to the one that is used for the augering tool (40) so that it can be used interchangeably to attach to the IE (24) unit. FIG. 5a shows the detector (50) inside the HSA (42) and the cable (53) attached to a pulley mechanism (55) that is used to insert and raise the detector (50) in-situ for a non destructive assay (NDA) in one aspect of the invention. Any other mechanical device can be used for this purpose. FIG. 5b shows the detector (52) housed in a steel tube (52) of appropriate diameter for protection or it may be inserted directly into the HSA without a tube covering it. The detector measures gamma and neutron radiation levels emitted by the contents of the VPU after grinding. The NDA instrumentation can also provide isotopic information of the radioactive materials that are present. The detector sends a signal that can be remotely monitored by an operator. Instead of this in-situ measurement it is possible to insert soil sampling devices into the HSA (42), remove samples and test a sample of the stabilized mixture (9) in the RE (54) or in an off-site laboratory. FIG. 6 shows the cement truck (66), and the pump (68) that is used to pump the grout mixture to the HSA (42) through the Hollow Stem (44). FIG. 7 shows the sectional view of the retrieval enclosure (RE) (54) and retrieval bucket (56) The RE (54) is attached to the EB (18) for retrieval after the grinding and the NDA operations are completed. The IE (24) and the ATE (26) are removed prior to attachment of the RE (54). The retrieval bucket (56) is approximately 30 gallons in volume and is used to scoop the stabilized contents from within the casing (8). The retrieval bucket is connected to shafts that can extend the complete length of the casing (8) to completely remove the stabilized contents. Full buckets are held in position near the top of the RE while a lateral moving retrieval hopper (58) is brought into position below the bucket by conventional mechanical devices. Two positions of retrieval hopper are shown in FIG. 7. Other means of removal such as screw conveyor; clam shell and pneumatic devices can be used instead of the retrieval bucket. CCTV cameras (not shown) may be attached to the interior walls of the RE. HEPA filters (not shown) are attached to the walls for removal of all particulates from escaping air. The cameras take a video of the contents as they are dumped on the conveyor belt (62) and ultimately into the receiving drum (60). FIG. 8 shows a sectional view of the augering tool in the ATE (26) attached to the drilling rig (48). The IE and EB are not separately shown in this figure and are shown incorporated into the ATE (26) that is placed on top of the casing (8). The augering tool (40) is shown in its position after the VPU and contents have been ground and mixed with the soil. (9). As explained in the Conclusions; Ramifications and Scope section below the ATE, IE and EB units can be combined into one unit in another aspect of the invention as shown in FIG. 8. The process begins with establishing the target or location for surrounding the VPU with the casing (8). The enclosure base (EB) (18) is installed over the VPU centerline with the help of the alignment pins (20). Following this casing (8) is driven into the soil surrounding the buried VPU using standard industry practices for hoisting and rigging. A vibratory hammer well known in the art is used to sink the casing (8) into the ground to depth of approximately 22 feet. This depth is approximately 5 feet below the bottom of the VPU. The casing (8) is 25 feet long and therefore approximately 3 feet remains above the ground level. The 3 feet extension is intentional and will provide a safety buffer during the subsequent stabilization operation. The next step in the process is to stabilize the contents of the VPU within the 4 feet diameter casing. In one aspect the IE (24) is attached on top of the EB (18). The rotational shaft (Kelly bar) (49) of the drilling rig (48) is attached to the auger shaft that protrudes through the top of the ATE (26) that is installed over the IE (24). The three part enclosure system is now ready for the stabilization operation. It is possible to combine the auger tool enclosure and the interface enclosure into one enclosure that has the same functionality as the two enclosures as shown in FIG. 8. The drilling rig (48) starts rotating the augering tool (40) within the ATE (26) and lowers it through the IE (24) and EB (18) continuing down through the soil (6) and shredding the wall of the VPU (10). This operation continues for six to ten hours; grinding the VPU contents and mixing it with the surrounding soil in the casing (8). During the grinding process low pressure, low volume dust suppression system (Dust Bond™, calcium chloride solution) is used through the attachment port (39) to reduce dust during augering. The grinding of the VPU (10) exposes the chemicals that have been stored in cans and vials inside the VPU (10) allowing chemical reactions to occur including the NaK reactions. These chemicals react violently with each other in the presence of oxygen or water and are rendered less harmful after they are allowed to react. The mixing with the soil allows the free liquids to be absorbed and the soil chemical mixture is thoroughly mixed together. The process is completely and safely contained within the casing (8) that surrounds the augering tool (40). After about six to ten hours the stabilized mixture (9) is uniform having irregular shaped particles in a size range between approximately 0.5″ and 3.0 inches. The stabilization process takes place under the ground and within the sealed structure formed by the casing (8), EB (18), IE (24) and ATE (26) eliminating the risk of contaminated waste reaching the surface. Air is continuously exhausted through HEPA filters (not shown) prior to being exhausted into the atmosphere. Port (30) is used for air sampling as necessary. The next step is to lift the augering tool (40) using the drilling rig and bring it into the original position in the ATE (26). High pressure, low volume water jet is introduced through the port (38) to wash the soil mixture off the augering tool (40). This cleaning is done during the lifting of the augering tool (40) by the drilling rig (48). Multiple levels of high pressure, low volume jets are used. Even after thorough washing there may still be some soil residue stuck on the augering tool. A port (46) is provided to insert a swab material such as filter paper to take a smear sample to test for radio isotopes. If the test shows higher levels than are permitted by current standards then the washing is continued until the smear test shows acceptable contamination levels. The next step is to use the drilling rig (48) to remove the ATE (26) after shutting the door (28) to isolate it from the IE (24) unit. As explained earlier, the ATE (26). The IE (24) and the EB (18) may be combined into one unit and provided with the same functionality as the separate units have. After the ATE (26) containing the augering tool (40) is removed from the IE (24) unit a spare ATE (26) containing the HSA (42) unit is attached to the IE (24) and the rotational shaft of the Kelly bar (49) is attached to the HSA (42) such that it can be lowered into the over casing that contains the stabilized mixture of soil and VPU contents (9). The HSA (42) has a hollow stem opening approximately 4 inches in diameter in which a gamma and neutron detector is inserted to measure the gamma and neutron emissions of the mixture. This in situ method allows for the classification of the waste as hazardous or non hazardous depending on the level of radioactivity detected. If the waste is considered hazardous because it exceeds the permitted radioactivity level it is classified as TRU waste when the radioactivity>100 nCi/gm. After the test results are obtained the probe assembly (52) is removed from the HSA (42) using a cable attached to a mechanical device such as a pulley mechanism. Instead of using the in-situ detector it is possible to test a sample of the stabilized mixture in another location such as in the RE (54) using a similar device or conducting the test in an outside laboratory. If the stabilized mixture (9) is determined to be TRU then the next step is the determination if dust control additives are required to reduce dusting during removal of the contents. For waste with excessive dust a fixative grout is introduced through the hollow stem of the HSA (42) and mixed with the stabilized contents for approximately one to two hours. This step is not necessary if it is determined that the mixture is not dusty and can be removed without a dust control additive. The drilling rig (48) is used to lift the HSA (42) into the ATE (26). The ATE (42) and IE (24) are then removed as one unit using the drilling rig (48). The next step is to place the RE (54) on top of the EB (18) as shown in FIG. 6. The RE (54) operates under a negative pressure (0.25 WG) to ensure that none of the air is leaked to the atmosphere. The technology for providing negative pressure is well known in the art and is not being described herein. The retrieval bucket (56) is attached to the drilling rig (48) and lowered into the casing (8) to scoop out the stabilized contents. Other devices such as screw conveyors can be used for this purpose. The retrieval bucket (56) has doors that are closed after the contents waste has been collected and the doors are provided with a release mechanism that discharges the contents into the hopper (58), which is placed on rails and can be laterally moved to provide access for the lowering and lifting of the retrieval bucket (56). The hopper (58) is provided with an outlet gate (64) through which the stabilized mixture that is retrieved from the casing (8) is discharged on to a conveyor belt (62). A video recording of the contents can be made for recording purposes using CCTV cameras (not shown) mounted within the RE (54) before the contents are loaded into new 55 gallon drums (60) for disposal as per applicable state regulations. If after testing it is determined that the stabilized mixture of waste and soil is not TRU then grout mixture (64) is pumped from a cement truck through the stem (44) of the HSA (42) through openings (not shown) provided at the bottom of the HSA (42) to completely fill the casing (8). FIG. 6 shows the grout mixture (64) exiting from the bottom of the HSA (42) that is rotating as the grout mixture is pumped into the casing (8). The HSA (42) is retracted before the grout sets up into the ATE (26) and the ATE (26) and IE (24) are removed from the top of the EB (18). Typically the grout will tend to set up within 12 or so hours to form a monolith. This monolith is excavated using excavating machinery well known in the art. The monolith is removed and buried horizontally into trenches that have been dug at the site. The trenches are covered with soil. Thus the reader will see that at least one embodiment provides a system and method to remediate, analyze and safely remove waste in buried containers. While the above description contains much specificity, these should not be construed as limitations on the scope, but rather as an exemplification of other possible embodiments thereof. For example: The enclosure base can be eliminated and other guiding devices can be used. A positioning device attached to the casing could serve the same purpose as the enclosure base that is used to center and position the interface enclosure and the retrieval enclosure over the casing. (ii) The augering tool enclosure and the interface enclosure can be combined into one unit and provided with the same functionalities as the two separate units. (iii) Inserting the casing into the soil around the buried VPU can be done by means other than the use of a vibratory hammer. Diesel; air or pneumatic pile drivers may be used instead of the vibratory hammer. (iv) The casing may be made of a metal other than steel and may have non-circular cross-section such as a rectangular cross-section. (v) Instead of the drilling rig other systems such as a crane can be used to move the ATE and augering tool within it into position over the IE. The crane can provide augering action of rotation and up and down motion similar to a drilling rig. (vi) Instead of the auger as the grinding tool other mechanical or non-mechanical (sonic) devices could be used to puncture the VPU and mix the contents with the soil. (vii) The non destructive assay (NDA) can be done in an external laboratory using commercially available testing instruments to test for radioactivity and the TRU status of the waste. (viii) Treatment methods during grinding can be grout free or use various compositions of grouting media such as bentonite to modify the rheology or fluidity of the grout. Grout can be introduced by various means instead of using the hollow stem auger as the path described above. (ix) There are other retrieval options. Instead of the bucket system described in the embodiments above, one can use an excavator with clam shell to retrieve the mixture. Other retrieval methods such as a vertical screw conveyor or pneumatic transfer can be used for mixture retrieval. (x) For certain types of non TRU waste it may be possible to use a conventional excavator to remove the VPU's along with the surrounding soil with or without grinding the VPU contents and mixing them with the soil. (xi) Other drilling technologies such as sonic drilling have been used in the industry.
	claims	1. An infrared radiation element comprising:a first insulating layer having heat insulating properties and electrically insulating properties;a heating element layer provided on the first insulating layer and configured to radiate infrared radiation when energized; anda second insulating layer provided on an opposite side of the heating element layer from the first insulating layer and having heat insulating properties and electrically insulating properties,the second insulating layer transmitting the infrared radiation radiated from the heating element layer, andthe heating element layer having such a sheet resistance that impedance of the heating element layer matches impedance of space which is in contact with the second insulating layer. 2. The infrared radiation element as set forth in claim 1, whereinthe sheet resistance of the heating element layer is selected so that an infrared emissivity of the heating element layer is not less than a predetermined value. 3. The infrared radiation element as set forth in claim 2, whereinthe sheet resistance of the heating element layer falls within a range of 73Ω/□ to 493Ω/□. 4. The infrared radiation element as set forth in claim 1, further comprising a substrate,the first insulating layer being provided on a surface of the substrate. 5. The infrared radiation element as set forth in claim 4, whereinthe substrate has an opening to expose the first insulating layer. 6. The infrared radiation element as set forth in claim 5, whereinthe heating element layer is positioned in a region in which the first insulating layer is in contact with the opening in a plan view. 7. The infrared radiation element as set forth in claim 5, further comprisinga pair of electrodes provided respectively on both ends of an opposite surface of the heating element layer from the first insulating layer. 8. The infrared radiation element as set forth in claim 7, further comprising:a pair of pads positioned in a region in which the opening is not provided in a plan view; anda pair of electrical connectors electrically connecting the pair of pads to the pair of electrodes, individually,the pair of pads being arranged to extend parallel to a predetermined direction, andthe pair of electrical connectors being arranged symmetrical about a center line passing through a center of gravity of the heating element layer and extending in the predetermined direction. 9. The infrared radiation element as set forth in claim 8, whereineach of the pair of electrical connectors is composed of two or more wires. 10. The infrared radiation element as set forth in claim 8, whereinthe pair of electrical connectors are made of tantalum. 11. The infrared radiation element as set forth in claim 1, whereinthe heating element layer is made of tantalum nitride or electrically conductive polysilicon.
	summary
046577300	claims	1. A nuclear reactor, comprising: a reactor pressure vessel, having a vertically oriented cylindrical tubular shell portion, the bottom of which is closed by a hemispherical shell portion having upper sidewalls; a core barrel disposed internally within said reactor pressure vessel; means mounted upon said reactor pressure vessel for engaging the periphery of said core barrel, comprising a cross beam member, and a pair of brackets connected to the opposite ends of said crossbeam member, said pair of brackets extending radially outwardly of said crossbeam member and engaging said reactor pressure vessel at the upper sidewalls of said hemispherical shell portion so as to radially space said crossbeam member from said reactor pressure vessel; recess means defined within said crossbeam member of said engaging means; key means secured to said core barrel and disposed within said recess means and vertically oriented channel means defined within the confines of said crossbeam member and said brackets of said engaging means for providing a vertically directed fluid conduit for coolant flow through said engaging means. means for transmitting radial load forces from said core barrel to said reactor pressure vessel as radially directed compression load forces, comprising said pair of brackets in the form of radially oriented and relatively divergent brackets, and whereby said radially directed compression load forces include oppositely directed, balanced force components. said core barrel comprises a bottom support plate; and said engaging means engage the outer periphery of said bottom support plate. shock absorber means disposed within said recess means and interposed between said engaging means and said key means. means defined upon the brackets of said engaging means for converting horizontal bending moments into circumferential shear and radial compression forces under horizontally disposed tangentially oriented force loads, wherein said brackets are radially oriented and relatively divergent. shock absorbing means mounted upon said crossbeam member of said engaging means. said shock absorbing means comprises vertically disposed plastically collapsible stainless steel cylinders. means defined upon the brackets of said engaging means for eliminating vertical bending moments under horizontally disposed tangentially directed force loading. means defining the center of gravity of said engaging means relative to said reactor pressure vessel within a plane extending perpendicular to said reactor pressure vessel and including the center of load of said engaging means under said horizontally disposed tangentially directed force loading conditions. means defined upon the brackets of said engaging means for converting vertical bending moments into circumferential shear and radial compression forces under vertical force loading. lower support surfaces on said brackets inclined with respect to both horizontal and vertical planes within said reactor vessel. said lower support surfaces are inclined at an angle .phi. of 60.degree. with respect to said vertical plane. 2. A nuclear reactor as set forth in claim 1, further comprising: 3. A nuclear reactor as set forth in claim 1, wherein: 4. A nuclear reactor as set forth in claim 1, further comprising: 5. A nuclear reactor as set forth in claim 1, further comprising: 6. A nuclear reactor as set forth in claim 1 wherein four said engaging means are provided, equiangularly disposed about the inner periphery of said pressure vessel. 7. A nuclear reactor as set forth in claim 1, further comprising: 8. A nuclear reactor as set forth in claim 7, wherein: 9. A nuclear reactor as set forth in claim 1, further comprising: 10. A nuclear reactor as set forth in claim 9, wherein said eliminating means comprises: 11. A nuclear reactor as set forth in claim 1, further comprising: 12. A nuclear reactor as set forth in claim 11, wherein said converting means comprises: 13. A nuclear reactor as set forth in claim 12, wherein:
	claims	1. A detector assembly for measuring flux in a nuclear reactor core comprising:a plurality of self-powered in-core detector arrangements each for measuring flux at a different one of a plurality of axial locations in the nuclear reactor core; andan assembly connector configured to be connected to a power plant connector, the assembly connector comprising a plurality of flux signal terminals each connected to one of self-powered in-core detector arrangements,at least one of the self-powered in-core detector arrangements comprising a set of at least two self-powered in-core detectors for measuring flux at a same one of the axial locations in the nuclear reactor core,each of the at least two self-powered in-core detectors including a sheath, a detector material section inside the sheath, an insulator between the sheath and the detector material, and a flux signal output line, the flux signal output lines of the at least two self-powered in-core detectors being joined together to provide a combined flux signal,the joined flux signal output lines being connected to a same one of the flux signal terminals of the assembly connector. 2. The detector assembly as recited in claim 1 wherein the detector material section is a same detector material for all of the at least two self-powered in-core detectors. 3. The detector assembly as recited in claim 1 wherein the detector material section is a same size and shape for all of the at least two self-powered in-core detectors. 4. The detector assembly as recited in claim 1 wherein the at least one of the self-powered in-core detector arrangements comprising the set of at least two self-powered in-core detectors comprise:a first of the self-powered in-core detector arrangements comprising a set of first self-powered in-core detectors for measuring flux at a first axial location in the nuclear reactor core, flux signal output lines of the first self-powered detectors being joined together to provide a first combined flux signal for identifying the flux of the nuclear reactor core at the first axial location; anda second of the self-powered in-core detector arrangements comprising a set of second self-powered in-core detectors for measuring flux at a second axial location in the nuclear reactor core axially offset from the first axial location, flux signal output lines of the second self-powered detectors being joined together to provide a second combined flux signal for identifying the flux of the nuclear reactor core at the second axial location. 5. The detector assembly as recited in claim 4 wherein each of the first self-powered in-core detectors includes a lead wire extending from the detector material section and transmitting a flux signal to one of the flux signal output lines,each of the first self-powered in-core detectors including a background wire spaced from the detector material section by the insulator and transmitting a background signal to a first background signal output line,each of the second self-powered in-core detectors includes a lead wire extending from the detector material section and transmitting a flux signal to one of the flux signal output lines,each of the second self-powered in-core detectors including a background wire spaced from the detector material section by the insulator and transmitting a background signal to a second background signal output line. 6. The detector assembly as recited in claim 5 wherein the first background signal output lines of the first self-powered detectors are joined together to provide a first combined background signal for the set of first self-powered in-core detectors and the second background signal output lines of the second self-powered detectors are joined together to provide a second combined background signal for the set of second self-powered in-core detectors. 7. The detector assembly as recited in claim 6 wherein the connector includes a first background signal terminal for outputting the first combined background signal and a second background signal terminal for outputting the second combined background signal. 8. The detector assembly as recited in claim 7 wherein the connector includes two thermocouple terminals and a collector terminal electrically connected to the sheaths. 9. The detector assembly as recited in claim 4 further comprising:a set of third self-powered in-core detectors at a third axial location, third flux signal output lines of the third self-powered detectors being joined together to provide a third combined flux signal for identifying the flux of the nuclear reactor core at the third axial location; anda set of fourth self-powered in-core detectors at a fourth axial location axially offset from the third axial location, fourth flux signal output lines of the fourth self-powered detectors being joined together to provide a fourth combined flux signal for identifying the flux of the nuclear reactor core at the fourth axial location,each of the third self-powered in-core detectors and the fourth self-powered in-core detectors including a respective sheath, a detector material section inside the sheath and an insulator between the sheath and the detector material section. 10. A method of providing a detector assembly for measuring flux in a nuclear reactor core comprising:arranging a plurality of self-powered in-core detector arrangements in the nuclear reactor core each for measuring flux at a different one of a plurality of axial locations in the nuclear reactor core;connecting an assembly connector to the self-powered in-core detector arrangements, the assembly connector comprising a plurality flux signal terminals each connected to one of self-powered in-core detector arrangements, the assembly connector configured to be connected to a power plant connector,at least one of the self-powered in-core detector arrangements comprising a set of at least two self-powered in-core detectors for measuring flux at a same one of the axial locations in the nuclear reactor core,each of the at least two self-powered in-core detectors including a sheath, a detector material section inside the sheath, an insulator between the sheath and the detector material, and a flux signal output line, the flux signal output lines of the at least two self-powered in-core detectors being joined together to provide a combined flux signal, andconnecting the joined flux signal output lines to a same one of the flux signal terminals of the assembly connector. 11. The method as recited in claim 10 wherein the detector material section is a same detector material for all of the at least two self-powered in-core detectors. 12. The method as recited in claim 11 wherein the detector material section is a same size and shape for all of the at least two self-powered in-core detectors. 13. The method as recited in claim 12 wherein the arranging of the plurality of self-powered in-core detector arrangements in the nuclear reactor core comprises:arranging a first self-powered in-core detector arrangement in the nuclear reactor core at a first axial location, the first self-powered in-core detector arrangement comprising a set of first self-powered in-core detectors for measuring flux at the first axial location in the nuclear reactor core, flux signal output lines of the first self-powered detectors being joined together to provide a first combined flux signal for identifying the flux of the nuclear reactor core at the first axial location; andarranging a second self-powered in-core detector arrangement in the nuclear reactor core at a second axial location axially offset from the first axial location, the first self-powered in-core detector arrangement comprising a set of second self-powered in-core detectors for measuring flux at the second axial location, flux signal output lines of the second self-powered detectors being joined together to provide a second combined flux signal for identifying the flux of the nuclear reactor core at the second axial location. 14. The method as recited in claim 13 wherein each of the first self-powered in-core detectors includes a lead wire extending from the detector material section and transmitting a flux signal to one of the flux signal output lines,each of the first self-powered in-core detectors including a background wire spaced from the detector material section by the insulator and transmitting a background signal to a first background signal output line,each of the second self-powered in-core detectors includes a lead wire extending from the detector material section and transmitting a flux signal to one of the flux signal output lines,each of the second self-powered in-core detectors including a background wire spaced from the detector material section by the insulator and transmitting a background signal to a second background signal output line,the first background signal output lines of the first self-powered detectors are joined together to provide a first combined background signal for the set of first self-powered in-core detectors and the second background signal output lines of the second self-powered detectors are joined together to provide a second combined background signal for the set of second self-powered in-core detectors. 15. The method as recited in claim 14 wherein the connector includes a first background signal terminal for outputting the first combined background signal and a second background signal terminal for outputting the second combined background signal. 16. The method as recited in claim 15 wherein the connector includes two thermocouple terminals and a collector terminal electrically connected to the sheaths.
046831150	abstract	Nuclear reactor fuel assembly having a grid-shaped spacer with square grid meshes, wherein mutually parallel rods are arranged, respectively, in a grid mesh, the spacer having flat outer straps extending transversely to the rods and an intermediate strip extending parallel to the rods between two of the respective outer straps, the intermediate strip being inclined relative to the two outer straps, including a rejection rise formed at the outside of the intermediate strip and extending in direction of a diagonal of a grid mesh located at a corner between the two outer straps, the rejection rise being disposed transversely to the two outer straps and being inclined downwardly towards two respective ends of the intermediate strip in longitudinal direction of the rods.
	summary
043448720	summary	The present invention relates to a method of removing waste products proceeding on the basis of solutions of fission products, particularly nitric solutions, which contain ruthenium. This method utilizes concentration and solidification, particularly vitrification. The present invention also relates to an apparatus which is suitable for carrying out this method. During the reworking of highly burned up nuclear fuel, a nitric aqueous phase with the entire fission products usually remains after the separation of uranium and thorium with organic extraction agents. In so doing, 7.3 m.sup.3 solution having a residue on ignition of 1.6% and an acidity of 1.45 M/l nitric acid is obtained, for example, per metric ton of heavy metal. These solutions, which due to their high radioactivity cannot be removed in a simple manner, are concentrated for a final storage, and the concentrate obtained is then preferably solidified by vitrification. This operation though simple in principle is complicated by the presence of nitrate, and particularly nitric acid, since the oxidizing conditions caused by their presence, at high temperatures, lead to evaporation of ruthenium-106 in the form of ruthenium tetroxide. In addition, toxic waste gases result, which contain nitrous fumes (NO.sub.x) and have a corrosive effect, causing additional problems. The ruthenium evaporation occurs particularly already during concentration of the solutions by distillation or similar methods of concentration. For this reason, the concentration and solidification are generally preceded by a denitration by adding reducing agents such as formic acid, formaldehyde, or sugar, according to which nitrous gases are liberated from the nitric acid and the easily decomposable nitrates. In subsequent condensers and washers, these nitrous gases can be reconverted into nitric acid. The very stable alkali and earth alkali nitrates decompose only at increased oven temperatures during the solidification or vitrification. The thereby acidic corrosive oven waste gases can therefore only be discharged into the atmosphere after costly washing. In addition to this customary denitration, concentration and solidification or vitrification, a method of treating chiefly neutral or alkali solutions of fission products which contain nitrates and nitrites is known. According to this known method, the solution of fission products is mixed with a quantity of urea which is stoichiometric relative to the nitrite and nitrate content of the solution; the solution is heated up, particularly to temperatures of at least 130.degree. C. to 180.degree. C., until the water content is removed. Such a dehydrating denitration in a closed receptacle is not usable with nitric solutions of fission products, because these solutions tend to foam very strongly without a corresponding decomposition. It is an object of the present invention to obtain a good separation of nitric acid from solutions of fission products without evaporation of ruthenium. This object, and other objects and advantages of the present invention, will appear more clearly from the following specification in connection with the accompanying examples and drawing, which is a flow diagram of the apparatus used to carry out the method of the present invention. The method of the present invention is characterized primarily in that the solution is concentrated to a solid content of at least about 15 to 20% in a vacuum at a pressure of at most about 50 mm Hg. It was unexpectedly discovered that an extensive separation of the nitric acid without evaporation of ruthenium could be achieved if the fission product solution was concentrated in a vacuum at the corresponding pertaining low temperatures. With such a vacuum concentration, less than 1 ppm ruthenium is present in the acid condensate, and the separated nitric acid can be recovered with relative ease. The concentrate which is obtained from the vacuum concentration can be temporarily stored. A particularly favorable refinement of the method of removing waste products according to the present invention consists however in a combination of vacuum concentration and subsequent solidification, particularly vitrification, accompanied by the addition of ammonia derivatives, such as calcium cyanamide or especially urea, which react with nitrate along with the formation of reaction products, such as nitrogen, laughing gas (nitrous oxide), carbon monoxide, dioxide, etc, which comprise no nitrogen oxides rich in oxygen, so that the nitrous fumes content of the waste gas remains low. By such a vitrification of the concentrate along with the addition of vitrifiers and, as the case may be, intermediate drying, the occurrence of nitrous gases in the oven waste gas is avoided. Pursuant to the present invention, a considerable simplification of the treatment of solutions of fission products, particularly nitric solutions, is obtained in that the normally customary denitration, concentration, drying, and fusion along with restraint of nitrous gases is replaced by the steps of vacuum concentration accompanied by simple recovery of nitric acid--followed, as the case may be, by drying--and fusing with ammonia derivatives, particularly addition of urea.
	description	This application claims the benefit of U.S. Provisional Application No. 61/625,325, filed Apr. 17, 2012. U.S. Provisional Application No. 61/625,325, filed Apr. 17, 2012, is hereby incorporated by reference in its entirety into the specification of this application. The following relates to the nuclear reactor arts, nuclear power generation arts, nuclear reactor safety arts, and related arts. Electrical power grids comprise an interconnected network (i.e., “grid”) of power generation components, power transmission components, power conditioning components, and power consuming components (i.e., “loads”). Ordinarily, operation of the components is interdependent so that, for example, a power generation plant is designed to operate supplying power to a switchyard delivering power to a (cumulative) load that has known characteristics with statistically predicable narrow fluctuations. These interconnections can be lost due to various failures. In particular, a “blackout” occurs when power supplied to the electrical power grid is abruptly interrupted. In such cases, it is known to operate a power generation plant in so-called “island mode” or “island mode of operation” where the plant is designed to accommodate the blackout condition. In the case of a nuclear power plant, station blackout introduces radiological safety considerations. In some approaches, no island mode operation is attempted; rather, upon loss of switchyard power the reactor trips, control rods scram to shut down the nuclear chain reaction, and decay heat removal systems are brought online. Diesel generators and/or batteries are relied upon to supply power for the safety systems. This approach ensures safety, but subsequently requires a lengthy reactor restart process. Typically, power generation capacity is lost for days or longer. Moreover, the abrupt shutdown can stress the turbine and other components. The Economic Simplified Boiling-Water Reactor (ESBWR) of GE-Hitachi (see http://www.nrc.gov/reactors/new-reactors/design-cert/esbwr/overview.html, last accessed Oct. 17, 2012) is designed to address station blackout by entering an island mode in which the switchyard breaker opens, a bypass valve dumps up to 110% of full steam load into the condenser, the BWR power output is reduced to about 40-60% over several minutes, and the (reduced) house electrical loads continue to be supplied by the turbine driven by the BWR. See “Advisory Committee on Reactor Safeguards ESBWR Design Certification Subcommittee”, Nuclear Regulatory Commission Official Transcript of Proceedings, Oct. 3, 2007 (Work Order No. NRC-1799). In other systems the bypass capacity is lower, e.g. 30% of full steam load. Id. These approaches advantageously avoid reactor scram and subsequent reactor restart, but have certain other disadvantages. During the initial steam bypass into the condenser, the turbine loses steam and undergoes a transient, which can stress the turbine. The steam dump into the condenser also stresses the condenser. In the case of a BWR, there is substantial condenser capacity to accommodate the steam bypass, but a pressurized water reactor (PWR) typically has relatively less condenser capacity. It has been suggested that the ability in the case of a PWR to dump steam to atmosphere might be utilized (Id.), but venting to atmosphere raises other regulatory issues or overpressure alarms that would likely delay the operational restart of the PWR-based nuclear power plant with the power grid. Disclosed herein are improvements that provide various benefits that will become apparent to the skilled artisan upon reading the following. In accordance with one aspect, a nuclear power plant comprises: a nuclear reactor comprising a pressurized water reactor (PWR) and a steam generator configured to transfer heat from primary coolant water heated by the PWR to secondary coolant water in order to convert the secondary coolant water to steam; a turbine connected with the steam generator to be driven by steam output by the steam generator; an electric generator connected with the turbine to be driven by the turbine to generate electricity; an electrical switchyard receiving electrical power from the electrical power generator during normal operation of the nuclear power plant; a condenser connected with the turbine to condense steam exiting the turbine; and a turbine bypass system. The turbine bypass system is configured to transfer a quantity of steam output by the steam generator to the condenser without passing through the turbine responsive to loss of offsite electrical power to the nuclear power plant wherein the quantity of steam transferred to the condenser without passing through the turbine is effective to (1) allow the nuclear reactor to power down without triggering steam generator or nuclear reactor pressurizer safety valve setpoints and (2) continue powering house electrical loads of the nuclear power plant using the turbine. In accordance with another aspect, a method is disclosed of operating a nuclear power plant that includes a pressurized water reactor (PWR), a steam generator, a turbine, an electric generator, and a condenser. The disclosed method comprises: operating the PWR to heat primary coolant flowing through a nuclear reactor core comprising fissile material immersed in the primary coolant water; operating the steam generator to convert secondary coolant feedwater to steam using primary coolant water heated by the operating PWR; operating the turbine by flowing steam from the steam generator through the turbine and then through the condenser; driving the electric generator using the turbine to generate electricity; conveying the generated electricity to an electrical switchyard; and responsive to a station blackout, transitioning the nuclear power plant to an island mode over a transition time interval. The transitioning includes performing transition operations including: at the beginning of the transition time interval, disconnecting the electric generator from the electrical switchyard and opening a bypass valve to convey bypass steam flow from the steam generator to the condenser wherein the bypass steam flow does not flow through the turbine; after opening the bypass valve, gradually closing the bypass valve over the transition time interval; and gradually reducing the thermal power output of the PWR over the transition time interval. In accordance with another aspect, a method is disclosed that operates in conjunction with a nuclear power plant comprising a pressurized water reactor (PWR) operating to heat primary coolant water, a steam generator using the heated primary coolant water to convert secondary coolant feedwater to steam, a turbine driven by steam from the steam generator and operatively connected with an electric generator, and a condenser connected with the turbine to condense steam after flowing through the turbine. The disclosed method comprises transitioning the nuclear power plant to an island mode over a transition time interval by transition operations including: responsive to detecting a station blackout, electrically isolating the nuclear power plant and opening a bypass valve to convey bypass steam flow from the steam generator to the condenser without flowing through the turbine; and gradually reducing the thermal power output of the PWR over the transition time interval. The transition operations do not include venting steam from the steam generator to atmosphere. In some embodiments, after opening the bypass valve, the bypass valve is gradually closed over the transition time interval. In some embodiments, a supplemental bypass valve is also opened responsive to detecting the station blackout, which conveys supplemental bypass steam flow from the steam generator to a feedwater system supplying secondary coolant feedwater to the steam generator, wherein the supplemental bypass steam flow does not flow through the turbine and does not flow through the condenser. Disclosed herein are island mode operation techniques suitable for use in a pressurized water reactor (PWR). The disclosed approaches avoid venting secondary coolant steam to atmosphere, instead employing steam bypass to the condenser. Overloading of the available PWR condenser capacity is avoided by gradually closing the bypass valve over the course of the transition to island mode in order to limit the time-integrated bypass stream flow to an amount sufficient to avoid tripping steam generator or pressurizer safety valve setpoints. Additionally, in some embodiments a portion of the bypass steam flow is sent to the feedwater system rather than to the condenser, effect using the feedwater as a supplemental condenser. These aspects also reduce the stress of the transient on the turbine. In some embodiments the final reduced reactor power level is 20% or less of full capacity—at this low reactor power level, the steam bypass flow can be stopped entirely, and the plant can run indefinitely on its own power in this steady state in island mode. On the other hand, if ancillary events ultimately trip the reactor, it is already at a low power level which facilitates safe reactor shutdown. FIG. 1 illustrates an illustrative nuclear reactor of the pressurized water reactor (PWR) type, which includes a pressure vessel comprising an upper vessel 2 and a lower vessel 4 joined by a mid-flange 6. The reactor pressure vessel houses a nuclear reactor core 8 comprising fissile material, e.g. 235U immersed in primary coolant water. Reactivity control is provided by a control rods system that includes control rod drive mechanisms (CRDMs) 10 and control rod guide frame supports 12. The illustrative CRDMs 10 are internal CRDMs disposed inside the pressure vessel and including CRDM motors 14 disposed inside the pressure vessel; however, external CRDMs with motors mounted above the pressure vessel and connected via tubular pressure boundary extensions are also contemplated. The pressure vessel of the operating PWR contains circulating primary coolant water that flows upward through the nuclear reactor core 8 and through a cylindrical central riser 16, discharges at the top of the central riser 16 and flows back downward through a downcomer annulus 18 defined between the pressure vessel and the central riser to complete the primary coolant circuit. In the illustrative PWR, primary coolant circulation is driven by reactor coolant pumps (RCPs) 20 which may be located where illustrated in FIG. 1 or elsewhere; moreover, natural circulation or the use of internal RCPs disposed inside the pressure vessel is also contemplated. Pressure inside the pressure vessel of the illustrative PWR is maintained by heating or cooling a steam bubble disposed in an integral pressurizer volume 22 of an integral pressurizer 24; alternatively, an external pressurizer can be connected with the pressure vessel by piping. The illustrative PWR is an integral PWR in which a steam generator (or plurality of steam generators) 26 is disposed inside the pressure vessel, and specifically in the downcomer annulus 18 in the illustrative PWR; alternatively, an external steam generator can be employed. In the illustrative integral PWR, secondary coolant in the form of feedwater is input to the steam generator 26 via a feedwater inlet 30, and secondary coolant in the form of generated steam exits via a steam outlet 32. In the alternative case of an external steam generator, the ports 30, 32 would be replaced by primary coolant inlet and outlet ports feeding the external steam generator. The illustrative integral PWR also includes a support skirt 34. With continuing reference to FIG. 1, the state of the balance-of-plant (BOP) in the steady state, i.e. during normal operation, is diagrammatically shown. The steam outlet 32 of the nuclear reactor delivers steam to a steam system 40 that drives a turbine 42 that turns an electric generator 44 so as to generate electricity that is delivered to an electrical switchyard 46 that feeds an electrical grid (not shown). Steam flows from the turbine 42 into a condenser 50 that condenses the steam to generate feedwater that is delivered by a feedwater system 52 to the feedwater inlet 30 of the steam generator 26 of the integral PWR so as to complete the steam cycle. Condensate generated inside the turbine 42 is also recaptured and added to the feedwater, as indicated by an arrow running from the turbine 42 to the feedwater system 52. In addition to feeding the switchyard 46, the generator 44 also delivers house electricity for running pumps, monitors, and other components of the nuclear reactor plant. In the diagrammatically illustrated BOP, the generator 44 feeds a medium voltage a.c. power system 60 which in turn powers a low voltage a.c. power system 62, which in turn powers a d.c. power system 64 that drives a vital a.c. power system 66. This arrangement advantageously allows for both d.c. and a.c. power for driving components of the nuclear reactor plant. Driving the vital a.c. power system 66 using the d.c. power system 64 enables convenient switchover to battery or diesel generator power (not shown) in the event that the usual power systems 60, 62, 64 fail. However, other electrical layouts are also contemplated, and the power systems 60, 62, 64, 66 shown in FIG. 1 are to be understood to be merely an illustrative example. With reference to FIG. 2, the normal operating state of the reactor is shown in an alternative diagrammatic representation that further includes additional components to provide further context, and also labels certain nominal operating settings for an illustrative small modular reactor (SMR) of the integral PWR type. In FIG. 2 (as well as in FIG. 4 to be described later), the following notation is used: “Fuel” denotes the nuclear reactor core; “CNX”=auxiliary condenser system; “CHW”=chilled water; “CNT”=containment; “ICI”=nuclear instrumentation; “RCS”=reactor coolant system; “ECC”=emergency core cooling system; “RCI”=reactor coolant inventory and purification system; “CRD”=control rod drives; “CCW”=component cooling water system; “FW”=feedwater; “STM”=steam; “CND”=condenser; “TRB”=turbine; “GEN”=generator; “SYD”=switchyard; “TBC”=turbine cooling building; “CIR”=circulating water; “ACM”=medium voltage alternating current power; “ACV”=vital alternating current power; “DC”=direct current power; “ACL”=low voltage alternating current power; and “ACX”=auxiliary alternating current power. As labeled in FIG. 2, the nominal operating settings for the illustrative SMR include: primary coolant pressure inside the pressure vessel 2, 4, 6 of 2064 PSIG; steam system 40 operating at a pressure of 840 PSIG; turbine 42 operating at 100% capacity; electrical generator 44 outputing 158 MWe (megawatts electrical); the condenser 50 operating at a pressure of 25.7″ Hg (inches mercury); and the feedwater system 52 delivering feedwater to the steam generator inlet 30 at 325° F. As further labeled in FIG. 2, nominal balance-of-plant (BOP) operational settings include the medium voltage a.c. power system 60 operating at 4176 VAC and the low voltage a.c. power system 62 operating at 483 VAC. With reference to FIG. 3, the nuclear power plant of FIG. 1 is shown, but during transition to the island mode of operation. In the situation depicted in FIG. 3, a station blackout has occurred, and in response a circuit breaker (or plurality of circuit breakers) has severed the electrical connection of the generator 44 to the switchyard 46. To accommodate the transient, a steam bypass valve 70 opens to divert steam flow so as to bypass the turbine 42 and flow directly to the condenser 50. For redundancy, it is contemplated to implement the steam bypass valve 70 as two or more bypass valves in parallel—for example, in one embodiment two 50% bypass valves are employed to implement the steam bypass valve 70. Optionally, a supplemental steam bypass valve 72 opens concurrently with the opening of the steam bypass valve 70. Opening of the supplemental steam bypass valve 72 sends a portion of the bypass steam flow directly to the feedwater system 52. This portion of the bypass steam flow thus bypasses both the turbine 42 and the condenser 50. The outlet of the steam bypass line controlled by the supplemental bypass valve 72 suitably terminates in a sparger or other component that dissipates the steam into a reservoir of feedwater or into a continuous flow of feedwater, e.g. through a feedwater pipe. In effect, this supplemental bypass steam path controlled by the supplemental bypass valve 72 employs the feedwater as a supplemental condenser, thus reducing the load on the condenser 50. FIG. 4 shows transition to the island mode of FIG. 3 using the diagrammatic representation of FIG. 2. Thus, the illustrative nuclear power plant is designed for the ability to operate with the loss of offsite power (i.e., operating in “island mode”). The island mode continues operation and supplies electrical power to the unit auxiliary transformer (e.g., powering the medium voltage a.c. power system 60) while the generator step-up transformer is disconnected from the switchyard 46 from 100 percent power. With reference to FIG. 5, the electrical layout supporting switching to island mode is diagrammatically shown. In FIG. 5, “UAT” stands for “Unit Auxiliary Transformer”, “RAT” stands for “Reserve Auxiliary Transformer”, “GSU” stands for “Generator Step-Up transformer”, and “SWGR” stands for “switchgear”. Also note that the electrical layout shown in FIG. 5 is for a “two-pack” nuclear power plant that includes two nuclear reactor units labeled “UNIT 1” and “UNIT 2” respectively. Only the circuitry for UNIT 1 is depicted in FIG. 5, with a line labeled “TO UNIT 2 GSU” indicating the parallel connection to UNIT 2. A station blackout, as used herein, is to be construed as encompassing a loss of power or other grid disturbance sufficiently severe that it calls for isolating the nuclear power plant from the electrical grid. When a station blackout is detected, breakers labeled with an asterisk (“”) in FIG. 5 trip to disconnect the nuclear reactor from the switchyard 46, and the reactor continues to run independently in island mode. When entering island mode (FIGS. 3 and 4), the nuclear power plant places UNIT 1 transformer 80 on the output from the generator 44 in front of the switchyard 46. (The transition for Unit 2 is analogous). The design has the ability to reject 100% of full grid load without a reactor or turbine trip. As shown in FIGS. 3 and 4, to accommodate the transient the turbine bypass system (e.g. bypass valve 70) is designed to dump sufficient steam to the condenser 50 to allow reactor power ramp-down without approaching steam generator or pressurizer safety valve set-points while the plant is still powering house loads 60, 62, 64, 66. With reference to FIG. 6, the transition to island mode is diagrammatically depicted by way of plotting predicted turbine-generator power (in gross MWe) and reactor power output (in MW thermal) as a function of time. In the illustrative example of FIG. 5, the nuclear power plant is again assumed to be a “two pack” with each reactor unit being a small modular reactor (SMR) of the integral PWR type. having a nominal operating power output of 530 MW thermal and a nominal turbine-generator output of 180 MWe. FIG. 6 plots data for one reactor unit of the two-pack. The transition to island mode is designed to occur over an 8 minute time period with the reactor unit power output dropping to 20% of the normal nominal output (i.e. to about 100 MW thermal). Also plotted in FIG. 6 is the setting of the steam bypass valve 70, which may optionally be implemented as a plurality of valves in parallel (e.g. two 50% bypass valves in one design) to provide redundancy. If provided, the operation of the optional supplemental bypass valve 72 which dumps steam into the feedwater system 52 (see FIGS. 3 and 4) parallels the plotted operation of the bypass valve 70. The relative bypass steam flows in the main bypass line controlled by the bypass valve 70 and in the supplemental bypass line controlled by the optional supplemental bypass valve 72 is chosen based on the effective condenser capacity of the feedwater system 52. As seen in FIG. 6, at the onset of the transition to island mode (time t=0 min in FIG. 6), the bypass valve 70 goes full open so that most or all steam bypasses the turbine 42. Over the next several minutes (e.g., over the next 8 minutes in illustrative FIG. 6), the reactor power is gradually decreased and simultaneously the setting of the bypass valve 70 is gradually transitioned from fully open at t=0 min to fully closed at t=8 min. The gradually reduction of steam output of the nuclear reactor leads to a gradual reduction in the turbine-generator electrical power output, until a minimum reactor load is reached at the end of the transition (e.g., at 8 minutes in the illustrative example of FIG. 6). Although FIG. 6 show linear transitions over the 8 minute time interval for each of the bypass valve setting, the turbine-generator power, and the reactor thermal power output traces, these characteristics can have other transient shapes, e.g. transitions with some curvature. The setting of the bypass valve 70 is a controlled parameter, and is preferably set to dump sufficient steam to the condenser 50 (and to the feedwater 52 via the supplemental bypass valve 72, if provided) to allow reactor power ramp-down without approaching steam generator or pressurizer safety valve setpoints while the plant is still powering house loads. This can be achieved by feedback control. For example, in one approach the bypass valve setting to keep the steam generator and reactor pressure at least (for example) 10% below their respective setpoints. In this way, the load placed on the condenser 50 during the (illustrative 8 minute) transition to island mode is minimized while still ensuring that the steam generator and reactor do not trip and cause a plant shutdown. The supplemental steam bypass provided by the optional supplemental bypass valve 72 further reduces the load on the condenser 50. The illustrative embodiments are directed to the illustrative integral PWR in which the steam generator 26 is disposed inside the pressure vessel. However, the disclosed approaches are alternatively suitably employed in conjunction with a PWR having an external steam generator. The disclosed approaches for switching a PWR to island mode without tripping the reactor advantageously enable a PWR to continue operation during a station blackout. When the blackout is lifted, the PWR can be brought back online by closing the breakers marked by asterisks (“”) in FIG. 5 and ramping the reactor power level back up to its nominal operating level. (The bypass valves 70, 72 are fully closed in the steady-state island mode, that is, after the end of the illustrative 8 minute transition period of illustrative FIG. 6, and so the bypass valves 70, 72 simply remain closed as the reactor is brought back online and ramped back to full power). The disclosed approaches for operating a PWR in island mode advantageously do not entail venting steam to atmosphere. Such venting to atmosphere is an acceptable operational procedure for a PWR, and does not introduce a radiological release because the steam generated by a PWR is secondary coolant. (In contrast, steam generated by a BWR is primary coolant and contains radiological contaminants, and therefore cannot be vented to atmosphere). However, it is recognized herein that venting the secondary coolant steam generated by a PWR to atmosphere is disadvantageous, at least because venting to atmosphere can trip overpressure alarms or activate other alarm conditions, thus delaying PWR reactor restart. The disadvantages of bypass to the condenser 50 are also remediated as disclosed herein by gradually reducing the bypass valve setting to minimize the time-integrated load placed on the condenser 50, and by optionally sending a portion of the bypass steam flow directly into the feedwater system 52 via the optional supplemental bypass valve 72. The preferred embodiments have been illustrated and described. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the invention be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
	abstract	According to the embodiment, a radiation detector includes a photoelectric conversion substrate converting light to an electrical signal and a scintillator layer being in contact with the photoelectric conversion substrate and converting externally incident radiation to light. The scintillator layer is made of a phosphor containing Tl as an activator in CsI, which is a halide. A concentration of the activator in the phosphor is 1.6 mass %±0.4 mass %, and a concentration distribution of the activator in an in-plane direction and a film thickness direction is within ±15%.
	claims	1. A method for handling radioactive solutions after decontamination of the surfaces of protective equipment, the method comprising the combined evaporation of alkaline and acidic solutions containing sodium hydroxide, potassium permanganate, oxalic acid and nitric acid to a solid residue, with subsequent calcination and mixing of the calcinate with the components of the fusion mixture containing oxides of titanium, calcium, iron (III) and aluminum in certain proportions, and the combined melting of all components to produce a ceramic matrix, wherein zirconium and manganese (IV) oxides are further introduced into the mixture of the calcinate and oxides of titanium, calcium, iron (III) and aluminum in the following component proportions, wt %:Calcinate of high-level waste10.0-20.0TiO253.0-57. CaO 9.0-11.0Fe2O34.5-5.5Al2O34.5-5.5ZrO24.5-5.5and the total content of MnO2 in the mixture does not exceed 10 wt %. 2. The method of claim 1, wherein the solid residue resulting from the evaporation of decontaminating solutions is calcined at 750 to 800° C. to fully decompose nitrates and carbonates. 3. The method of claim 1, wherein the calcinate is fused at 1,350° C. or higher for 1 hour to produce a monolithic fused ceramic material.
048448605	abstract	A fuel element support grid for supporting a plurality of nuclear fuel elements intermediate their ends has at least some of the pairs of intersecting and slottedly interlocked strips including pairs of intersecting integral fluid flow directing vanes along at least one adjacent edge of each of the strips of the pair. Welds attach the pair of vanes to each other thereby providing welded attachment of the strips. The welds may be at the intersection of the vanes remote from their areas of integral attachment to their respective strips or they may be adjacent to their areas of integral attachment to their respective strips. The strips may be bent to provide the strip function and the arch function within the same stream engaging profile as the strip alone presents.
041538447	claims	1. Apparatus for determining the degree of spin polarization of an electron beam, in which there are provided a monocrystal of electrically conducting or semiconducting material having a surface disposed perpendicularly to the radiation direction of said electron beam and formed parallel to a crystal structure plane designed to scatter the electrons of said beam, and also means for measuring the intensity of backscattering of electrons by the monocrystal in two respective directions at complementary angles to said radiation direction of said beam, having the improvement consisting in that: (a) first means for accelerating or decelerating electrons, consisting of a plurality of electron lens elements of tubular or of diaphragm form at different electrical potentials are provided for accelerating or decelerating the electrons of said beam to velocities suitable for monochromatizing said electrom beam to a degree required in a subsequent stage; (b) monochromatizing means downstream of said first accelerating or decelerating means are provided for monochromatizing said electron beam; (c) second means for accelerating or decelerating electrons, consisting of electron lenses of tubular or diaphragm form, are provided and located downstream of said monochromatizing means for adjusting the energy to a value required for the scattering of the electrons of the monochromatized beam and for focussing the beam on said surface of said monocrystal; (d) said monocrystal is arranged next in line downstream of said second accelerating or decelerating means; (e) said means for measuring electron backscattering intensity consists essentially of at least one pair of detectors for measuring the intensity of electron beams backscattered at complementary angles from said surface of said monocrystal, and (f) means interposed between said surface of said monocrystal and said backscattering intensity measuring means are provided for separating or deviating the low-energy portion of the backscattered electrons produced by ineleastic interaction of electrons of said beam with said monocrystal. 2. Apparatus for determining the degree of spin polarization of an electron beam as defined in claim 1, in which said means for separating or deviating the low-energy portion of the backscattered electrons produced by inelastic interaction of electrons of said beam with said monocrystal is constituted so as to provide an opposing electric field for repelling low-energy electrons. 3. Apparatus for determining the degree of spin polarization of an electron beam as defined in claim 1, in which said means for separating or deviating the low-energy portion of the backscattered electrons produced by inelastic interaction of electrons of said beam with said monocrystal is constituted so as to provide a field in front of each of said detectors for deviating the low-energy electrons away from said detectors. 4. Apparatus for determining the degree of spin polarization of an electron beam as defined in claim 1, in which said means for measuring electron backscattering intensity consists of four of said detectors adjustable for detecting backscattered electron beams, which detectors are disposed in pairs in two planes intersecting each other in the direction of the electron beam incident upon said monocrystal that are as nearly as possible perpendicular to each other. 5. Apparatus for determining the degree of spin polarization of an electron beam as defined in claim 1, in which said detectors of said means for measuring electron backscattering intensity are constituted as collector plates disposed in the hemispherical space above said monocrystal facing towards the arriving electron beam. 6. Apparatus for determining the degree of spin polarization of an electron beam as defined in claim 5, in which there are disposed electron multiplier channel plates in front of said collector plates.
	description	The present application claims priority to Japanese patent application No. 2011-191313 filed on Sep. 2, 2011, the entire content of which is hereby incorporated by reference. The present disclosure relates to a method and device for checking for faults in regulator valves for regulating the flows of fluids. Conventionally, in chemical plants, and like, positioners have been provided in regulator valves used in the flow rate processes thereof, to adjust the opening of regulator valves using the positioners. The positioner would be provided with a calculating portion for calculating the difference between an opening setting value sent from a higher-level device and an actual opening value, fed back from the regulator valve, to generate an electric signal, as a control output, in accordance with this difference, an electro-pneumatic converting device for converting, into an air pressure signal, the control output generated by the calculating portion, and a pilot relay for amplifying this air pressure signal, converted by the electro-pneumatic converting device, and outputting it to an operating device of the regulator valve as an air pressure signal. See, for example, Japanese Unexamined Utility Model Registration Application Publication S62-28118. FIG. 23 shows the flow of input/output signals in a system wherein a positioner is combined with a regulator valve. In this figure, 100 is the positioner and 200 is the regulator valve, where the positioner 100 is provided with an electrical module 1, an EPM (electro-pneumatic converter module) 2, and a pilot relay (an air pressure amplifying module) 3. The electrical module 1 inputs the opening setting signal Iin and the opening X of the valve that is fed back from the regulator valve 200, to generate an EPM driving signal Duty as the control output. The EPM 2 inputs the EPM driving signal Duty from the electrical module 1 to convert the EPM driving signal Duty into a nozzle back pressure Pn. The pilot relay 3 inputs the nozzle back pressure Pn from the EPM 2 to generate an operating device pressure Po from the nozzle back pressure Pn. The regulator valve 200 inputs the operating device pressure Po from the positioner 100 to adjust the opening X of the valve in accordance with the operating device pressure Po. FIG. 24 shows a diagram of a linear approximation of the steady-state input/output relationship between the individual modules within the positioner 100 and the regulator valve 200 when operating properly. FIG. 24(a) shows the input/output relationship in the electrical module 1 (the relationship between the opening setting signal Iin and the EPM driving signal Duty); FIG. 24(b) shows the input/output relationship in the EPM 2 (the relationship between the EPM driving signal Duty and the nozzle back pressure Pn); FIG. 24(c) shows that the input/output relationship in the pilot relay 3 (the nozzle back pressure Pn and the operating device pressure Po); and FIG. 24(d) shows the input/output relationship in the regulator valve 200 (the relationship between the operating device pressure Po and the degree of opening X). Note that this example is an example of a forward operating type (air-to-open) wherein the opening is larger in accordance with the amount of air that goes into the regulator valve 200. [Fault Checking in Regulator Valves] In the regulator valve 200 it is possible to detect the fluid reactive force that acts on the valve shaft (the force from the process fluid) from the relationship between the operating device pressure Po and the degree of opening X. FIG. 25 shows the change in the input/output relationship of the regulator valve 200 when there is a fluid reactive force. In this figure, I is a characteristic showing the steady-state input/output relationship when operating properly (the characteristic when there is no load), where this input/output relationship is modified by the occurrence of the fluid reactive force so to be as shown by characteristic I′. When there is no load, the relationship between the operating device pressure Po and the degree of opening X exhibits a balance between the spring force and the force of the air pressure. When a fluid reactive force is produced, that balance is disrupted. Consequently, it is possible to detect a difference in the operating device pressure Po by comparing to the state wherein no reactive force is produced (when there is no load). It is possible to detect fluid pressures outside of the use range through monitoring this difference. Moreover, it is possible to detect aberrations in the frictional force that acts on the valve shaft from the relationship between the operating device pressure Po and the degree of opening X. See, for example, Japanese Translation of PCT International Application 2006-520038 and Japanese Translation of PCT International Application 2005-538462. FIG. 26(a) shows the hysteresis characteristics of the input/output relationship between the operating device pressure Po and the degree of opening X when operating properly. The input/output relationship will be different when the operating device pressure Po changes in the rising direction and when it changes in the falling direction, producing a hysteresis width W between the characteristic in the rising direction and the characteristic in the falling direction. As shown in FIG. 26(b), this hysteresis width W will vary depending on the frictional force. Consequently, it is possible to check for a fault through comparing with the hysteresis width W from a time of proper operation. Note that multiplying one half of the hysteresis width W by the operating device diaphragm surface area produces the static frictional force, where this static frictional force may also be used as an indicator value. However, in the regulator valve fault checking method set forth above, when performing fault checking of the regulator valve using data from the processing operation during processing operations, in some cases it is not possible to check well for faults in the regulator valve. For example, let us consider the case of a fault (a large fluid reactive force) in the regulator valve illustrated in FIG. 25. In this case, when the regulator valve is moved quickly during a processing operation, then, due to a delay, the input/output relationship will deviate greatly from characteristic I (the steady-state model) that shows the steady-state input/output relationship when operating properly. (See FIG. 27.) Because of this, there will be an incorrect diagnosis that there is a fault in the regulator valve. Moreover, let us consider a fault (a large frictional force) in the regulator valve, in FIG. 26. In this case, with the technology set forth in Japanese Translation of PCT International Application 2006-520038 and Japanese Translation of PCT International Application 2005-538462, data will also be used wherein the degree of opening X and/or the operating device pressure Po is moved rapidly. When such data becomes large, the hysteresis width W that is calculated becomes large, even if there is actually no change in the frictional force. (See FIG. 28.) Because of this, there will be an incorrect diagnosis that there is a fault in the regulator valve. Note that one may consider creating a dynamic model that includes the delay of the regulator valve, and performing the fault check based on the dynamic model that has been produced. However, this method requires an excessively large amount of work to produce highly accurate dynamic models, such as to produce the equations of motion (referencing, for example, Japanese Unexamined Patent Application Publication H07-77488), and the amount of calculation overhead during operation will also be large, so the fault checks cannot be performed easily. The present disclosure addresses such problems, and the object thereof is to provide a method and device for checking for faults in positioners, able to perform fault checks of regulator valves easily and accurately during processing operations. The present disclosure, in order to achieve such an object, discloses a regulator valve fault checking method for performing fault checking of a regulator valve for regulating the flow of a fluid, including a step of sampling periodically a signal that is inputted into the regulator valve and, as an output from the regulator valve, a degree of valve opening, a step of calculating a speed of change of the input signal that has been sampled, a step of calculating a speed of change of the degree of valve opening that has been sampled, a step of calculating a weighting depending on a combination of the speed of change of the input signal and the speed of change of the degree of valve opening, based on a weighting function that has been established in advance, and a step of performing fault checking of the regulator valve based on the input signal and the degree of valve opening that have been sampled and on the weighting that has been calculated. For example, in the present disclosure, if the input signal into the regulator valve is an operating device pressure, then the operating device pressure is sampled at regular intervals as the input signal into the regulator valve, the valve opening is sampled at regular intervals as the output from the regulator valve, and the speed of change of the operating device pressure that has been sampled, and the speed of change of the valve opening that has been sampled, are calculated. Given this, a weighting is calculated in accordance with a combination of the speed of change of the operating device pressure and the speed of change of the valve opening, based on weighting functions established in advance, and fault checks of the regulator valve are performed based on the operating device pressures and degrees of opening, which have been sampled, and on the calculated weighting. For example, in the present disclosure, the weighting is defined as 1 if the speed of change of the operating device pressure and the speed of change of the valve opening are both low, and the weighting is defined as 0 otherwise, and fault checking for the regulator valve is performed using the operating device pressures and degrees of valve opening wherein the speeds of change are low. Doing this eliminates data that are very different from the characteristic that indicates the steady-state input/output relationship, when operating properly, during processing operation, and eliminates data that are very different from the width of hysteresis during proper operation, making it possible to perform fault checking of the regulator valve. While in the present disclosure the weighting is calculated in accordance with a combination of the speed of change of the input signal and the speed of change of the valve opening, based on a weighting function that is established in advance, a weighting function may be used wherein the weighting is divided into a weighting component that is in accordance with the speed of change of the input signal and a weighting component that is in accordance with the speed of change of the valve opening, and the weighting function may be one that combines the weighting component that is in accordance with the speed of change of the input signal and the weighting component that is in accordance with the speed of change of the degree of opening. Moreover, the weightings need not necessarily be binary values of 0 and 1, but instead they may be weightings that are larger as the speeds of change are smaller. Moreover, the present disclosure also discloses systems wherein the positioner is combined into the concept of the regulator valve. That is, it is possible to consider the entire system wherein a positioner and a regulator valve are combined as being a single regulator valve. In this case, the opening setting signal that is the input signal into the positioner would correspond to an input signal into the regulator valve. In the present disclosure, the input signal into the regulator valve and the valve opening, as an output from the regulator valve, are sampled periodically, the speed of change of the input signal that is sampled and the speed of change of the valve opening that is sampled are calculated, a weighting is calculated in accordance with a combination of the speed of change of the input value and the speed of change of the valve opening, based on a weighting function that is established in advance, and fault checking of the regulator valve is performed based on the input signal and valve opening that are sampled and on the weighting that is calculated, thus making it possible to perform fault checking of the regulator valve easily and accurately through eliminating the data that is greatly different from the characteristic that indicates the steady-state input/output relationship when operating properly, and eliminating data that deviates greatly from the width of hysteresis when operating properly, during the processing operation. Embodiments according to the present disclosure will be explained in detail below based on the drawings. Here an example wherein fault checking is performed by calculating a fluid reactive force, as a fault check indicator value, from the input/output signals (the operating device pressure Po and the degree of opening X) of a regulator valve will be explained first as a first embodiment, after which an example wherein fault checking is performed by calculating a hysteresis width, as a fault check indicator value, from the input/output signals (the operating device pressure Po and the degree of opening X) will be explained as a second embodiment. FIG. 1 shows the structure of the critical portions of a fault checking device 300 for performing a fault check of a regulator valve 200 with the flow reactive force as the fault check indicator value. This fault checking device 300 includes a CPU 4, a memory portion 5 that is a ROM, a RAM, or the like, and interfaces 6 and 7. Note that this fault checking device 300 may be provided within a positioner 100 or a regulator valve 200, or may be provided outside of the positioner 100 and the regulator valve 200. FIG. 1 shows an example wherein it is provided on the outside of the positioner 100 and the regulator valve 200. The operating device pressure Po that is the input signal into the regulator valve 200 is branched and inputted through the interface 6 into the CPU 4, and the degree of opening X, which is the output from the regulator valve 200, is branched and inputted through the interface 7 into the CPU 4. The CPU 4 operates in accordance with a program PG that is stored in the memory portion 5. In addition to the program PG referenced above, a linear approximation formula F1 that represents the steady-state input/output relationship, when operating properly, of the regulator valve 200 (the relationship between the operating device pressure Po and the degree of opening X (when there is no load)), and weighting functions G11 and G12, for calculating weightings in accordance with combinations of the speed of change of the operating device pressure Po and the speed of change of the degree of opening X, are stored in the memory portion 5. [Linear Approximation Formula F1] In the first embodiment, the linear approximation formula F1 that indicates the steady-state input/output relationship, when operating properly, in the regulator valve 200 is calculated from the design specification of the regulator valve 200. In this case, the linear approximation formula F1 wherein the degree of opening varies between 0 and 100% with a spring range between 80 and 240 kPa is established as X=a1×Po+b1 (where a1=0.625 and b1=−50), and stored in the memory portion 5. Note that when there is no design specification for the regulator valve 200, or the like, the average values of the operating device pressure Po and the degrees of opening X may be taken in a state wherein there are proper operations, such as immediately after maintenance, after a specific time interval of settling in states wherein the opening setting signal Iin is at 25%, 50%, and 75% (referencing FIG. 2), to perform a calculation from three points using the least squares method. In this case, that which is caused to be in the steady-state need not necessarily be three points. Moreover, a non-linear approximation (such as a non-linear regression equation such as multivariate approximation or a support vector machine, or the like), may be used instead of the linear approximation. [Weighting Functions G11 and G12] In the first embodiment, in the weighting functions G11 and G12 for calculating the weightings in accordance with combinations of the speed of change of the operating device pressure Po and the speed of change of the opening X, G11 is established as a weighting function for obtaining a first weighting component wPo from the speed of change of the operating device pressure Po, and G12 is established as a weighting function for obtaining a second weighting component wX from the speed of change of the degree of opening X. A weighting w1 is calculated in accordance with the combination of the speed of change of the operating device pressure Po and the speed of change of the degree of opening X as w1=wPo×wX, as described below, from the weighting components wPo and wX obtained from the weighting functions G11 and G12. FIG. 3(a) shows one example of the weighting function G11. In the first embodiment, as illustrated in FIG. 3(a), the speed of change of the operating device pressure Po (kPa) is defined as vPo (kPa/sec), and if the absolute value of this speed of change of vPo is no more than a threshold value Poth, then wPo is 1, and otherwise it is 0. FIG. 3(b) shows one example of the weighting function G12. In the first embodiment, as illustrated in FIG. 3(b), the speed of change of the degree of opening X (%) is defined as vX (%/sec), where, in a range wherein the absolute value of the speed of change vX is no more than a threshold value Xth, wX is 1, and otherwise it is 0. Here the threshold values Poth and Xth are established with the tolerance value for the speed of change vPo of the operating device pressure Po as Poth, and the speed of change vX of the degree of opening X that is produced by the delay when the operating device pressure Po is increased to Poth is established as Xth. Note that the tolerance value Poth of the speed of change vPo of the operating device pressure Po indicates a tolerance value for the speed of change vPo wherein there is no risk of an incorrect diagnosis as a fault in the regulator valve due to this delay. The tolerance value Poth may be obtained through repeated experimentation. [Fault Checks During Processing Operations] During processing operations, the CPU 4 periodically reads in the operating device pressure Po that is inputted into the regulator valve 200 and the degree of opening X that is outputted from the regulator valve 200, to perform the fault checking on the regulator valve 200. FIG. 4 shows a main flowchart for the fault checking process that is performed by the CPU 4. The CPU 4 reads in the operating device pressure Po (k) and the degree of opening X (k), calculates the speed of change of the operating device pressure Po and the speed of change of the degree of opening X that have been read in, and calculates a weighting w1 (k) in accordance with the combination of the speed of change of the operating device pressure Po and the speed of change of the degree of opening X that have been calculated (Step S101). The subroutine for the process that is performed in Step S101 is illustrated in FIG. 5. The CPU 4 reads in the operating device pressure Po (k) and the degree of opening X (k) at the current sampling interval (the kth sampling interval) (Step S201 and S202), and calculates, as vPo (k) the speed of change in the operating device pressure Po (k) from the current operating device pressure Po (k) and the previous operating device pressure Po (k −1) (Step S203). Moreover, it calculates, as vX (k) the speed of change of the degree of opening X (k) from the current degree of opening X (k) and the previous degree of opening X (k −1) (Step S204). In this case, with the sampling interval defined as T (sec), vPo (k) (kPa/sec) can be calculated by Equation (1), below, and vX (k) (%/sec) can be calculated through Equation (2), below:vPo(k)=(Po(k)−Po(k-1))/T (1)vX(k)=(X(k)−X(k-1))/T (2) The CPU 4 then calculates, from the speed of change vPo (k) of the operating device pressure Po (k), a weighting component wPo (k) that depends on the speed of change vPo (k) following the weighting function G11 (FIG. 3(a)) that is stored in the memory portion 5 (Step S205). At this time, if the absolute value of the speed of change vPo (k) is no greater than the threshold value Poth, then wPo (k) will equal 1, but if the absolute value of the speed of change vPo (k) exceeds the threshold value Poth, then wPo (k) will equal 0. The weighting component wX (k) that depends on the speed of change vX (k) is calculated from the speed of change vX (k) of the degree of opening X (k) following the weighting function G12 (FIG. 3(b) that is stored in the memory portion 5 (Step S206). In this case, if the absolute value of the speed of change vX (k) is equal to or less than the threshold value Xth, then wX (k) will equal 1, but if the absolute value of the speed of change vX (k) exceeds the threshold value Xth, then wX (k) will equal 0. Following this, the CPU 4 calculates, from the weighting component wPo (k), calculated in Step S205, and the weighting component wX (k), calculated in Step S206, the weighting w1 (k) that depends on the combination of the speed of change vPo (k) of the operating device pressure Po (k) and the speed of change vX (k) of the degree of opening X (k) as w1 (k)=wPo (k)×wX (k) (Step S207). In this case, because w1 (k) is calculated as w1 (k)=wPo (k)×wX (k), the weighting w1 (k) will only be 1 when the conditions in the Conditional Equation (3), below, are satisfied, and the weighting w1 (k) will be 0 otherwise:If (\|vPo(k)\|≦Poth) AND (\|vX(k)\|≦Xth) (3) That is, the weighting w1 (k) will be 1 only when the absolute value of the speed of change vPo (k) of the operating device pressure Po (k) is no more than Poth and the absolute value of the speed of change vX (k) of the degree of opening X (k) is no more than Xth, and otherwise the weighting w1 (k) will be 0.[When w1(k)=0] The CPU 4 then checks whether or not the weighting w1 (k) is 1 (Step S102 (FIG. 4)), where if the weighting w1 (k) is not 1 (Step S102: NO), then k is incremented (Step S105), and after confirming that a calculation unit time interval (fault check evaluation time interval) that has been set in advance has not elapsed (Step S106: NO), processing returns to Step S101. Note that in this example, the fault check evaluation time interval in Step S106 is one day.[When w1(k)=1] If the weighting w1 (k) is 1 (Step S102: YES), then the CPU 4 establishes the category i to which the degree of opening X (k) belongs (Step S103). FIG. 6 shows the subroutine for the process that is performed in Step S103. The CPU 4 first checks whether or not the degree of opening X (k) is X (k)≧100% (Step S301). If here the degree of opening X (k) is equal to or greater than 100% (Step S301: YES), then the category i is set to i=20 (Step S302). If the degree of opening X (k) is not equal to or greater than 100% (Step S301: NO), then the category i is set to i=X (k)/5+1 (Step S303). Note that in the calculated value for i=X (k)/5+1, the digits after the decimal are truncated. As a result, if the opening X (k) is assumed to take a value between 0 and 100%, then the range of 0 through 100% is divided into 20 categories, each having a width of a 5% opening. Following this, the CPU 4 updates the maximum value and minimum value for the operating device pressure Po in the category i to which the opening X (k) belongs (Step S104 (FIG. 4)). FIG. 7 shows the subroutine for the process that is performed in Step S104. Note that in this subroutine, Max_p (i) indicates the maximum value for the operating device pressure Po within the category i, and Min_p (i) indicates the minimum value for the operating device pressure Po in the category i. The default values for Max_p (i) and Min_p (i) are described below. The CPU 4 first checks whether or not the operating device pressure Po (k) is Po (k)>Max_p (i) (Step S401). If here Po (k) is greater than Max_p (i) (Step S401: YES), then Po (k) is used as the new Max_p (i) (Step S403). If Po (k) is not greater than Max_p (i) (Step S401: NO), then a check is performed as to whether or not Po (k)<Min_p (i) (Step S402). If here Po (k) is less than Min_p (i) (Step S402: YES), then Po (k) is used as the new Min_p (i) (Step S404). If Po (k) is no more than Max_p (i) and no less than Min_p (i) (Step S402: NO), then neither Max_p (i) nor Min_p (i) is updated. Given this, the CPU 4, after performing the processes for updating Max_p (i) and Min_p (i), increments k (Step S105 (FIG. 4)), and, upon confirming that the fault check evaluation time interval has not elapsed (Step S106: NO), returns to Step S101. Through repeating Step S101 through S106 the operating device pressures Po (k) and the degrees of opening X (k) wherein the weighting w1 (k) is zero are excluded, and only those operating device pressures Po (k) and degrees of opening X (k) wherein the weighting w1 (k) is 1 will be extracted (referencing FIG. 10), where these extracted data are used as valid data (data subject to extraction), and a maximum value Max_p (i) and a minimum value Min_p (i) for the operating device pressures Po within the category i are calculated for each category i. [When the Fault Check Evaluation Time Interval has Expired] When the fault check evaluation time interval has expired (Step S106: YES), that is, when the incremented value of k in Step S105 indicates that the fault check evaluation time interval has expired, then the CPU 4 calculates the fluid reactive force in each category i as a fault check indicator value (Step S107). FIG. 8 shows the subroutine for the process that is performed in Step S107. The CPU 4 first sets i=1 (Step S501). Given this, with Fq (i) defined as the fluid reactive force for the i=1 category, the maximum value Max_p (i) and the minimum value Min_p (i) for the operating device pressure Po in that category i are substituted into Equation (4), below, to calculate the fluid reactive force Fq (i) for the i=1 category (Step S502). Note that Xi=2.5+(i-1)×5:Fq(i)=(Xi−b1)/a1−(Max—p(i)+Min—p(i))/2 (4) Equation (4), above, represents the difference, on the Po axis, between the steady-state input/output relationship, when operating properly, in the regulator valve 200, indicated by the linear approximation formula F1 that is stored in the memory portion 5, and the data (the substituted values) that indicate the input/output relationship gathered in category i. That is, the central value ((Max_p (i)+Min_p (i))/2) between the maximum value Max_p (i) and the minimum value Min_p (i) for the operating device pressure Po in category i is used as a representative value for the operating device pressure Po in category i, and the central value (Xi) for the range of degrees of opening in category i is used as a representative value for the degree of opening X in category i, and the difference between the representative value and the data when operating properly is shown on the Po axis (referencing FIG. 11). This difference is calculated as the fluid reactive force Fq (i) for category i. Note that Fq (i) is a pressure (kPa), but the units can be converted from a pressure (kPa) into a force (N) through multiplying by the surface area of the diaphragm of the operating device (m2)×10−3. After calculating the fluid reactive force Fq (i) for category i=1, the CPU 4 repeats the processing procedures of Step S501 through S504 while incrementing i (Step S504) until i reaches 20 (Step S503: YES). Doing so causes the fluid reactive force (i) for category i to be calculated for each of the categories i (referencing FIG. 12). Additionally, after calculating the fluid reactive forces Fq (i) for each category i, the CPU 4 then uses the fluid reactive forces Fq (i) calculated for each of the categories i as fault check indicator values and compares the fluid reactive forces Fq (i) to threshold values that have been established in advance (Step S108 (FIG. 4)), and if even one of the fluid reactive forces Fq (i) exceeds a threshold value (Step S108: YES), provides a fault notification (Step S109). After the fault notification of Step S109, or in response to NO in Step S108, the CPU 4 resets all of the maximum values Max_p (i) and minimum values Min_p (i) for the operating device pressures Po in all of the categories i to the default values (Step S110), returns to the procedure of Step S101, and repeats the same operating procedures. FIG. 9 illustrates the subroutine of the process that is performed in Step S110. The CPU 4 first sets i=1 (Step S601). It then sets Max_p (i)=−INF, and Min_p (i)=INF. Here INF is an extremely large value (a positive value), in excess of a range that would normally be assumed by the operating device pressure Po. As a result, Min_p (i) will be set to a positive value (the default value) in excess of the range that would normally be assumed by the operating device pressure Po, and Max_p (i) is set to the negative value that is the inverse of Min_p (i) (the default value). After setting Max_p (i) and the minimum value Min_p (i) for category i=1 to the default values, the CPU 4 repeats the processing operations of Step S601 through S604, while incrementing i (Step S604) until i=20 (Step S603: YES). As a result, Max_p (i) and the minimum value Min_p (i) for category i are set to the default values for all of the categories. By setting Max_p (i) to −INF (a negative value) and the minimum value Min_p (i) to INF (a positive value) for the category i, for each category i, in Step S110 and then returning processing to Step S101, the values of Max_p (i) and Min_p (i) will be updated to Po (k), regardless of the value that arrives for the operating device pressure Po (k) when the updating procedure for Max_p (i) and the minimum value Min_p (i) is performed in Step S104. At the point in time wherein the fault check evaluation time interval elapses, if Max_p (i) and/or Min_p (i) of the ith category have not been updated even once, that is, if the default values remain, then the fluid reactive force calculation is not performed in Step S107, and it is assumed that the fluid reactive force for the ith category cannot be calculated, so the threshold value evaluation is not performed. In this way, in the first embodiment, those data that deviate greatly from the characteristic I that represents the steady-state input/output relationship, when operating properly, during processing operations are eliminated, and the fault check of the regulator valve 200 is performed accurately using the simple steady-state model. Note that while in the first embodiment weighting functions G11 and G12 are used for calculating weightings according to the combinations of the speed of change of the operating device pressure Po and the speed of change of the degree of opening X, where rectangular weighting functions such as shown in FIGS. 3(a) and (b) are used, a triangular weighting function such as shown in FIGS. 13(a) and (b) may be used instead. In the weighting function G11′, shown in FIG. 13(a), if vPo is 0, then wPo is set to 1, but in the range wherein the absolute value of vPo is no greater than the threshold value Poth, instead wPo may gradually grow larger toward vPo=0, where otherwise wPo is 0. In the weighting function G12′ shown in FIG. 13(b), wX is 1 if vX is 0, wherein a range wherein the absolute value of vX is no larger than the threshold value Xth, wX may gradually grow larger towards vX=0, and wX is 0 otherwise. Moreover, instead, in the weighting function G11′, for example, illustrated in FIG. 13(a), wPo may be made larger as vPo gradually approaches vPo=0 from positions that are further separated in the positive direction or negative direction, and in the weighting function G12′ illustrated in FIG. 13(b), wX may be made gradually larger as vX approaches vX=0 from positions that are further separated in the positive direction or the negative direction. Moreover, the weighting function for calculating the weighting depending on the combination of the speed of change of the operating device pressure Po and the speed of change of the degree of opening X need not necessarily be divided into weighting functions G11 and G12, but rather may be a single weighting function that combines G11 and G12 (a three-dimensional function). The same is true for the triangular weighting functions G11′ and G12′, which may be a single weighting function combining G11′ and G12′ (a three-dimensional function). While in the fault checking device 300 according to the first embodiment the fault checking for the regulator valve 200 is performed as operating procedures of the CPU 4 following a program PG, when the functions performed by the operating procedures by the CPU 4 are expressed as blocks, the CPU 4 can be expressed as an operating device pressure sampling portion 411 for sampling periodically the operating device pressure Po that is inputted into the regulator valve 200, an opening sampling portion 421 for sampling periodically the degree of opening X that is outputted from the regulator valve 200, an operating device pressure change speed calculating portion 431 for calculating the speed of change vPo (k) of the operating device pressure Po (k) from the current operating device pressure Po (k) and the previous operating device pressure Po (k −1), sampled by the operating device pressure sampling portion 411, an opening change speed calculating portion 441 for calculating the speed of change vX (k) of the degree of opening X (k) from the current degree of opening X (k) and the previous degree of opening X (k −1), sampled by the opening sampling portion 421, a weighting calculating portion 451 for calculating the weighting w1 (k) in accordance with the combination of the speed of change vPo (k) of the operating device pressure Po (k) and the speed of change vX (k) of the degree of opening X, based on the weighting functions G11 and G12 that are stored in the memory portion 5, and a fault check indicator value calculating portion 461 for calculating the fault check indicator value Fq (i) for each category i for the regulator valve 200 during the fault check evaluation time interval from the operating device pressure Po (k), sampled by the operating device pressure sampling portion 411, the degree of opening X (k), sampled by the opening sampling portion 421, the weighting w1 (k), calculated by the weighting calculating portion 451, and the linear approximation formula F1 that is stored in the memory portion 5. Note that while in the first embodiment the speed of change vPo (k) of the operating device pressure Po (k) is calculated from the current operating device pressure Po (k) and the previous operating device pressure Po (k −1) and the speed of change vX (k) of the degree of opening X (k) is calculated from the current degree of opening X (k) and the previous degree of opening X (k −1), instead it is possible to perform a linear approximation calculation using the least-squares method using a signal over a specific time interval from the past and then to use the rate of change of the slope of the approximation equation. FIG. 14 shows the structure of the critical components of a fault checking device 400 for performing fault checking for a regulator valve 200 using a value for the hysteresis width as the fault check indicator value. In the fault checking device 400 as well, as with the first embodiment, a CPU 4, a memory portion 5, such as a ROM or a RAM, and interfaces 6 and 7 are provided. Note that this fault checking device 400 may also be provided within the positioner 100 or the regulator valve 200, or may be provided outside of the positioner 100 and the regulator valve 200. FIG. 14 shows an example wherein it is provided outside of the positioner 100 and the regulator valve 200. The operating device pressure Po that is the input signal into the regulator valve 200 is branched and inputted through the interface 6 into the CPU 4, and the degree of opening X, which is the output from the regulator valve 200, is branched and inputted through the interface 7 into the CPU 4. The CPU 4 operates in accordance with a program PG that is stored in the memory portion 5. In addition to the program PG referenced above, a hysteresis width W1 in the characteristic (the hysteresis characteristics of the operating device pressure Po and the degree of opening X) that represents the input/output relationship, when operating properly, of the regulator valve 200, and weighting functions G21 and G22, for calculating weightings in accordance with combinations of the speed of change of the operating device pressure Po and the speed of change of the degree of opening X, are stored in the memory portion 5. [Hysteresis Width W1] In this second embodiment, the hysteresis width W1 when the regulator valve 200 is operating properly is calculated from the design specification of the regulator valve 200 and stored in the memory portion 5. Note that if there is no design specification for the regulator valve 200, then, when in a proper operating state, such as immediately following maintenance, a low-speed ramped input may be applied to the positioner 100, reciprocating over the entire opening range thereof, as illustrated in FIG. 15(a), to obtain data for the operating device pressure Po and the opening X, as shown in FIG. 15(b), and the hysteresis width W1, when operating properly, may be calculated from the result. [Weighting Functions G21 and G22] In the present embodiment, the weighting functions G21 and G22, as illustrated in FIGS. 16(a) and (b), are the same as those of the weighting functions G11 and G12 described in the first embodiment (FIGS. 3(a) and (b)), so explanations are omitted here. [Fault Checks During Processing Operations] During processing operations, the CPU 4 periodically reads in the operating device pressure Po that is inputted into the regulator valve 200 and the degree of opening X that is outputted from the regulator valve 200, to perform the fault checking on the regulator valve 200. FIG. 17 shows a main flowchart for the fault checking process that is performed by the CPU 4. In this flowchart, the procedures in Step S111 through S116 are the same as the procedures in Step S101 through S106 explained in the first embodiment (FIG. 4), and thus are omitted here. [When the Fault Check Evaluation Time Interval has Expired] When the fault check evaluation time interval has expired (Step S116: YES), then the CPU 4 calculates the hysteresis width in each category i as a fault check indicator value (Step S117). FIG. 18 shows the subroutine for the process that is performed in Step S117. The CPU 4 first sets i=1 (Step S511). Given this, with Ft (i) defined as the hysteresis width for the i=1 category, the maximum value Max_p (i) and the minimum value Min_p (i) for the operating device pressure Po in that category i are substituted into Equation (5), below, to calculate the hysteresis width Ft (i) for the i=1 category (Step S512, see FIG. 19).Ft(i)=Max—p(i)−Min—p(i) (5) After calculating the hysteresis width Ft (i) for category i=1, the CPU 4 repeats the processing procedures of Step S511 through S514 while incrementing i (Step S514) until i reaches 20 (Step S513: YES). Doing so causes the hysteresis width (i) for category i to be calculated for each of the categories i (referencing FIG. 20). Additionally, after calculating the hysteresis width Ft (i) for each category i, the CPU 4 then reads in the hysteresis width W1 from the time of normal operation, stored in the memory portion 5, and uses as a threshold value a value wherein a specific value α has been added to this hysteresis width W1 to compare the hysteresis widths Ft (i) to this threshold values (Step S118 (FIG. 17)), and if even one of the flow hysteresis widths Ft (i) exceeds a threshold value (Step S118: YES), provides a fault notification (Step S119). After the fault notification of Step S119, or in response to NO in Step S118, the CPU 4 resets all of the maximum values Max_p (i) and minimum values Min_p (i) for the operating device pressures Po in all of the categories i to the default values (Step S120), returns to the procedure of Step S111, and repeats the same operating procedures. The resetting to the default values in Step S120 is the same as the operating procedure in Step S110 in the first embodiment (FIG. 4), so the explanation thereof will be omitted here. In this way, in the second embodiment, those data that deviate greatly from the hysteresis width, when operating properly, during processing operations are eliminated, and the fault check of the regulator valve 200 is performed accurately using the hysteresis width. Note that as shown in the first embodiment, the valve shaft is affected by the fluid reactive force during operation, changing the relationship between the operating device pressure Po and the degree of opening X. However, the hysteresis width W is dependent on the frictional force, and, as shown in FIG. 22, is not changed greatly by the fluid reactive force. Because of this, the second embodiment does not cease to be effective even under the influence of the fluid reactive force. While in the fault checking device 400 according to the second embodiment the fault checking for the regulator valve 200 is performed as an operating procedure of the CPU 4 following a program PG, when the functions performed by the operating procedure by the CPU 4 are expressed as blocks, the CPU 4 can be expressed as an operating device pressure sampling portion 412 for sampling periodically the operating device pressure Po that is inputted into the regulator valve 200, an opening sampling portion 422 for sampling periodically the degree of opening X that is outputted from the regulator valve 200, an operating device pressure change speed calculating portion 432 for calculating the speed of change vPo (k) of the operating device pressure Po (k) from the current operating device pressure Po (k) and the previous operating device pressure Po (k −1), sampled by the operating device pressure sampling portion 412, an opening change speed calculating portion 442 for calculating the speed of change vX (k) of the degree of opening X (k) from the current degree of opening X (k) and the previous degree of opening X (k −1), sampled by the opening sampling portion 422, a weighting calculating portion 452 for calculating the weighting w2 (k) in accordance with the combination of the speed of change vPo (k) of the operating device pressure Po (k) and the speed of change vX (k) of the degree of opening X, based on the weighting functions G21 and G22 that are stored in the memory portion 5, and a fault checking portion 462 for calculating the fault check indicator value Ft (i) for each category i for the regulator valve 200 during the fault check evaluation time interval from the operating device pressure Po (k), sampled by the operating device pressure sampling portion 412, the degree of opening X (k), sampled by the opening sampling portion 422, and the weighting w2 (k), calculated by the weighting calculating portion 452. Note that while in the second embodiment the speed of change vPo (k) of the operating device pressure Po (k) is calculated from the current operating device pressure Po (k) and the previous operating device pressure Po (k −1) and the speed of change vX (k) of the degree of opening X (k) is calculated from the current degree of opening X (k) and the previous degree of opening X (k −1), instead it is possible to perform a linear approximation calculation using the least-squares method using a signal over a specific time interval from the past and then to use the rate of change of the slope of the approximation equation. Moreover, while in the second embodiment the hysteresis width is calculated for each category i as Ft (i)=Max_p (i)−Min_p (i) in Step S117, the frictional force may be calculated for each category i as Ft (i)=(Max_p (i)−Min_p (i))/2. (See FIG. 21.) If the frictional force is used for Ft (i), that, in Step S118, the hysteresis width W1 for the time of proper operation, which is stored in the memory portion 5, may be read out, a half value for this hysteresis width W1 (W½) may be calculated, and a value where this half value (W½) of the hysteresis width W1 is added by a specific value β may be used as the threshold value, where this threshold value may be compared to the frictional force Ft (i). Conversely, the half value (W½) of the hysteresis width W1 when operating properly may be stored in the memory portion 5, and a value where this half value (W½) of the hysteresis width W1 is added by a specific value β may be used as the threshold value, where this threshold value may be compared to the frictional force Ft (i). While in this case Ft (i) is a pressure (kPa), the units can be converted from a pressure (kPa) into a force (N) through multiplying by the surface area of the diaphragm of the operating device (m2)×10−3. Moreover, while in the embodiments set forth above the explanation is for performing fault checking on a regulator valve 200, instead fault checking may be performed in the same manner as described above, when the entire system wherein a positioner and a regulator valve are combined is considered to be a single regulator valve. In this case, the opening setting signal Iin that is the input signal into the positioner 100 would correspond to an input signal into the regulator valve, and the fault checking for the system as a whole (the regulator valve) would use this opening setting signal Iin and the degree of opening X. The regulator valve fault checking method and device according to the present disclosure may be used in checking for faults in regulator valves used in fluid flow rate processes in chemical plants, and the like, as a method for checking for faults in regulator valves for adjusting flows of fluids.
040240177	claims	1. A method of measuring burn-up of nuclear fuel in a nuclear reactor including a core, comprising the steps of introducing a neutron flux probe of constant composition of at least two different nuclides which deliver two separable activities produced by two different neutron energies to a measuring point of the reactor core the burn-up of which is to be measured during operation of the reactor, the probe producing two measuring signals, each measuring signal being a function of the local flux of a different neutron energy changing with the burn-up at the measuring point, comparing the two signals and computing the burn-up on the basis of the comparison. 2. The method of claim 1, wherein the probe is moved into into the reactor core, the probe being capable of delivering two separable activities with at least two different neutron energies, the probe is permitted to remain in the nuclear fuel for a predetermined period of time, the probe is then removed and subjected to a measurement of the activities, and the burn-up is computed by comparing at least two of the activities. 3. The method of claim 2, wherein the activities are separable by their decay characteristics, the number of pulses of each energy is determined in at least two measuring channels associated with the activities, and the burn-up is computed by comparing the determined numbers of pulses. 4. The method of claim 2, wherein the activities are separable in time, at least two activity measurements are made in at least two predetermined time intervals, and the burn-up is computed by comparing the activity measurements. 5. The method of claim 2, wherein the probe is constituted by a column of balls or a helical spring, and the column of balls is introduced into the nuclear fuel through guide tubes distributed through the core. 6. The method of claim 2, wherein the probe comprises manganese and a metal selected from the group consisting of nickel, vanadium and gold, or vanadium and nickel. 7. The method of claim 6, wherein the probe also comprises a metal selected from the group consisting of iron, chromium and titanium. 8. The method of claim 1, wherein fission chambers are located in the fuel, the fission chambers being charged with different fissile materials, and the measuring signals are produced in the fission chambers. 9. The method of claim 8, whrein the fission chambers are fixedly arranged in the nuclear fuel. 10. The method of claim 8, wherein the fission chambers are temporarily introduced into the nuclear fuel to produce the measurements. 11. The method of claim 8, wherein at least two of the fission chambers are formed into a structural unit. 12. The method of claim 8, wherein the reactor has fixedly arranged fission chambers and associated calibrating chambers arranged to be moved through guide tubes distributed through the nuclear fuel during the operation of the reactor, comprising the steps of introducing additional fission chambers charged with a different fissile material into a respective one of the guide tubes to produce the measuring signals for comparison, the measuring signals being computed when the movable additional fission chambers are at the level of the associated fixed fission chambers. 13. An apparatus for measuring burn-up of nuclear fuel in a nuclear reactor, comprising two fission chambers of different sensitivity constant in time with respect to the local neutron spectrum of the reactor and changing as a function of the local burn-up, the fission chambers being arranged in the reactor core at a measuring point and each fission chamber producing a measuring output signal, each measuring output signal being a different function of the local neutron energy distribution changing as a function of the burn-up, and means designed to compute a value associated with the local burn-up on the basis of comparison of the two output signals. 14. An apparatus for measuring burn-up of nuclear fuel in a nuclear reactor, including a core and guide tube means leading into the core, said guide tube means having an activation section within the core, comprising 1. a measuring system comprising elements of an alloy of at least two components having a constant mixing ratio, the components of the elements delivering two separable activities produced by two different neutron energies, and the elements being movable through the activation section of the guide tube means into the reactor core, 2. a detector unit outside the reactor and connected to the measuring system, the movable elements being received from the activation section in the reactor core through the guide tube means, 3. means arranged to receive and compare the output signals and designed to compute a value associated with the local burn-up on the basis of comparison of the output signals. 15. The apparatus of claim 14, wherein the elements are balls. 16. The apparatus of claim 14, wherein the elements consist of a helical spring.
062698737	summary	FIELD OF INVENTION The invention pertains to a method for controlling the heat flux through a heat exchanger immersed in a pool with the aid of a thermal valve. Although the process and apparatus described below can be used in numerous fields, they are particularly useful in respect to the control of heat in a nuclear reactor from which it is desired to remove residual power. BACKGROUND OF THE INVENTION It is useful to understand what is meant by the residual power of a nuclear reactor. When a nuclear reactor is shutdown by introducing a source of high counter reactivity into the core, the number of fissions in the core very rapidly is reduced to a negligible number within a few seconds. However, the radioactive fission products produced in the core of the reactor during normal operation continue to produce a significant amount of power which can amount to several percent of the normal power production of the reactor. Regardless of the cause or the manner in which shutdown is effected, it is necessary to remove such residual power by a reliable means in order to prevent excessive heating of the core, which could lead to shutdown. Numerous devices exist in the prior art for removing the residual power of a nuclear reactor. These devices are generally characterized as having one or more auxiliary loops, in parallel or branched from the main loops which extract heat from the reactor during normal operation. The auxiliary loops are used for the removal of the residual power only when the reactor is shutdown. The heat emitted by the reactor core is consequently extracted into a cold source by two types of circuits, one constituted by main loops for normal operation and the other constituted by auxiliary loops for shutdown operation and removal of the residual power. Such circuitry requires a system to permit the routing of the heat flux to the appropriate heat source. Typically, such routing takes place by closing or opening mechanical valves on the circuits. A typical prior art system is shown in FIG. 1 which is described below. SUMMARY OF THE INVENTION The invention pertains to a method for controlling heat exchange in a nuclear reactor. The nuclear reactor contains: (a) at least one thermal valve; PA1 (b) at least one heat exchanger having a coolant flowing therein; the heat exchanger is immersed in a pool containing a fluid; PA1 (c) a container confining the heat exchanger; the container has an upper part with an opening therein and a lower part having means for introducing the fluid through the lower part; and PA1 (d) means for partially or totally opening or closing the opening in the upper part and means for partially or totally opening or closing the opening in the lower part. PA1 1. closing the opening in the upper part to thereby vaporize the fluid, in order to cause a cessation of heat exchange between the coolant and the fluid; and PA1 2. opening the opening in the upper part to thereby cause the fluid to be heated and to rise by convection, thereby permitting heat exchange to occur between the coolant and the fluid. The method for controlling the heat exchange in the above-described nuclear reactor comprises two steps:
048329061	abstract	A fuel assembly comprises a channel box, upper and lower tie plates fixed to the upper and lower portion of the channel box and a bundle of fuel rods enclosed in the channel box and retained by the upper and lower tie plates. The bundle of fuel rods includes ordinary fuel rods containing fissile material not containing gadolinia, and gadolinia-containing rods each containing gadolinia therein and having a larger outer diameter than that of the ordinary fuel rod. The gadolinia-containing rod has pellets enclosed in a closed cladding, and the outer diameters of the pellets also are larger than these of fuel pellets of the ordinary fuel rods.
	abstract	A novel material boron carbide high polymeric fiber fabricated from the following parts of raw materials by weight: 50-60 parts of boron carbide, 150-193 parts of high polymeric ethylene emulsion with a concentration 40%-50%, 116 parts of hydrochloric acid with a concentration 37%, 3-5 parts of antioxidant, and 7 parts of catalyst, and fabricated in a 2500-2800° C. high-temperature high-pressure furnace and then in a high temperature-resistant spinning furnace. The novel material boron carbide high polymeric fiber produced according to the present invention exhibits performances such as extremely good resistance against high temperature and low temperature, super anti-acid and anti-base performance, excellent extensibility, wear resistance and anti-impact capability, and resistance against ultraviolet and the like. The boron carbide high polymeric fiber may be used in fields such as firearms manufacture, maritime rescue, fire protection and fire fight, anti-bullet and anti-explosion armor, biochemical nuclear industry treatment, and may be extensively applied to civil field, aerospace, military fairs and national defense. The material is recyclable and pollution-free.

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