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Papik33792WPS18 China's Vocational and TechnicalTraining WPS19 Coie d'ivoire's Vocational andTechnical Education Harold Noah John Middleton June 1988 W. Ketema33651Christiaan Grootaert June 1988 R. Vartanian34678WPS20 Imports and Growth in Africa Ramon Lopez Vinod ThomasJune 1988 61679WPS21 Effects of European VERs on JapaneseAutos WPS22 Methodological Problems in Cross-Country Analyses of Economic Growth WPS23 Cost-Effective Integration ofImmunization and Basic Health Servicesin Developing Countries: The Problemof Joint Costs Jaime de Melo Patrick Messerlin June 1988 S. Fallon61680jean-Paul Azam Patrick Guillaumont Sylvi3ne GuillaumontJune 1988 E. Zamora33706A. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799752198.pdf | https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=fb1120fa3b8064307c2f6d5ac856bc2b377ffced | Central African Republic |
Mead Over, Jr. July 1988 N. Jose33688 | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799752198.pdf | https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=fb1120fa3b8064307c2f6d5ac856bc2b377ffced | Central African Republic |
Deperte.nt of the MivyS Clasefia~tianto WMA81YzK ?~~~Ltle.
M(tbOds of Spectral Amala.
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Approved by:______C BestAvailableCopy Chapter 20Chemical Analysis of Luminescence# 107.
EXCITATION AND RECORDING OF RADIANCE DURING THEIATrVAIV Mr CHMIC ANALYSIS OFEXCITATION OF LUMINESCENCE. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
The photo-excitation canbe effecte3 by any of the three methods indicated in Fig 202.Prom the emission spectrum of the source (1), ter (2), a narrow spectrum band has been serrated which then,by means of a condenser (3), will be focused on the investi-gated object (5). | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
The recording part plus setup can be per-through a fil-7r ., I .trum -- 1 Selement, formed in many different ways.For a qualitative analysis, quiteoften a visual observation of theradiance is all that is required.To meter the integral intensityof the radiance, photosuters arebeing used into whose opening theluminescence will be focused bya condenser (4). | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
when it the energy distribution in is necessary to determineIn those casesof luminescence a speotro-the speo-photometric devise (t) is usedinstead of a photometer.
Here,either the watcher's eye (a visualmethod) or a photo-film, photo-photo-amplifter, etc.
(an objective method) can serveas the receiver of em"ssions (7).of the method ofSRegardless the experiment applied rays of theexciting light can enter the receiv-er together with the luminescence.Fig.
202. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
202.
Three possible ways of exciting the lumi- The mostdrasic errors may occurnesconce: a- front excitta- when the radiance to be meterEdtion; b- side excitation; c- lighting source; 2,2'- cr- frequency range of the excitirpossed light-filters; 3 , 4 -condensers; 5- obJect to be investigated; 6- mono- chromator; 7- receiver of eftskson.
through excitation; 1- elver Is very sensitive in of a'Crossed filters Is being appl! | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
-_Immedtately after the source (I),a ftlter (2) absorb the visible part of thespectrum, and will let through t1.,has a low Intensity, and the rpc-7o pre';ent the above, a metho'is mounted which w1i'.light.theultra violet emission. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
A second filter,(2') mounted after *;it I4 ... alyzed obiect (5), will let ,hr,,,,'in the luminescence 91 Vit will completely absorb the ex.tn(cid:127) lIl(cid:127)n.rays.is necessary to determine the:n those cases when it cnape of the luminescence spectrum, ters can be used only with a certain reservation.
t., select such a light-filter (21) which would fully absorbtne light of luminescence. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
ways, not evenly as per its 1 he luminescence spectrum itself.to a certain degree absorb the emitted radiance (andthe method of crossed f12l-is hardspectrum) this distorting the shape ofIn practice, this filter will al-It The most often used method of excitation i3 shown in Fig.to its surface.
With such arrangement of appa-the rays of the exciting light are directed at202,A.
Here, an angle of }0° - 450 to the specimen surface. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
is done at 90 ratus, only a negligible part of the exciting light rays dis-sipated by the vessel walls and the surface of the objectitself, will enter the receiver.
The above setup has no par-ticular advantage in those cases when the investigated objectis avidly absorbing the rays of the exciting light. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
They areonly slightly penetrating the object mass, and the receiverwill record the actual radiance emitted by the specimen surface.At the same time, absorption (see below) the influence of the luminescence secondaryreduced to a minimum.The watchingis it Sometimes, is convenient to use the method shown inFig.
202,B, where the rays of the exciting light are at ý0oto the direction of observation. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
The above method is beingapplied when working with solutions which only to a very smalldegree are absobing the rays of the exciting light.
there assumed that over their entire travei through the solu-tion, the exciting rays have a constant intensity of radionce.With such a setup, Le reduced to a minimum to lower the secondary absorption, the light source should be positioned in such a way that theradiance was excited along the front wall of-the vessea, at 9g0to the direction of watching. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
it the exciting light whiCh was absorbed by the emanating subst-ance; likewise, the above methd is suitable for metering thedegree of the radiance polarization.The above method is used whenis necessary to take into consideration the percentage ofthe influence of the dissipated light canIt isthethe degree of the radiance polarization is much hlýinerWhen metering the polarization, either a polarized ornatural light is used as a source of excitation.
With theformer, than with the lr~tter. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
With theformer, than with the lr~tter.
sion.. With the polarized l a polarization prism will be mcu(cid:127)ir,ted after the source (1); ever, to less tnan one-half of the orig!nal.
Consequently, method might be used when inves'sip-ating the objects with an-intensive radiance.
Natural I!.Th- Is being used when work:ni;in weekly luminescence objects w'iose radian..ce has a 2onsP.,:b1'-.sea as a source of exclfat'c;._gb'. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
i,&w-the prism will reduce the tntenslty of the exciting i'P.the atove!-an be used for conver-Formula >1"1.3) ______ -.
- ,-.ee Zf polariza!:n*on.
J, *Te spectrum apparat As : metering the pclarizert '.. qe'e: 7.degre!
(J) r.e ; 1ld be replace!
by t:,ethe spectr'um ofz -eeve of pla;'.-:,, larAzatt)n, a Quartz monochr mrat.,r snall be mountedi after•ne sourze (1), and the raulanct.
Pxcite.i by differen- wave-iengths.The method shcwn in Fig. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
, where the so'Arce (1) ofthe object to be investigated (5) and the receiv-excitation, er (7) are all mounted on the same optical axis, the leastmUttable for investigationw of thc luminescence, and therefcreseldom used.
Here, with a "throi:'2h" excitation, there is abiggest chance that the exciting light will enter the receiver,and very Morecver, t:on (see below) can be particularly high. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
This method isused when investigating a lengthy radiance (phosphorence).After the excitation has beer, already stopped, and no excitinglight can enter the receiver.in such a case the influence if the secondary absorp-crossed filters will be required to stop it.is For other types of excitation (the cathode X-ray, radio -active, etc. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
emissions), different other sources of excitationare being used, but the recording part of the installation re-mains the same.In the luAineacence analysis, quite often one has to dealIn result, the luminescence intensity of the spec-with small amounts of substances, many of them with a weakradiance.
.imen under investigation can turn out to be very small,Indeed, and its measuring - very difficult. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Thus, important to select the most favorable conditions for theexperiment.it is veryBeside being characteristic to the substance itself, theintensity of the radiance depends primarily on the intensityof the exciting light; usuailly, this intensity is being deter-mined by the amount of absorbed energy of the exciting sourceradiance.
Therefore, for exciting an intensive radiance, cri-tical is not the magnitude of the source Integral brightness,but its brightness in the absorbed spectral zone. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Consideringthat different sources have a different distribution of energyalong their respective spectrum.
When selecting a source oneshould establish how high is its radiance in the spectrum inter-val to be used.
Usually, sector close to the maximum of the substance absorption apectrim;tnen, luminescence spectrum due to "ts secondary absorption (see be-lcw) will be at its minimum, and the s-nemes, 202, 8 and C, -the radiance intensity at its max'mum.in the scheme shown in Fig. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
202, A, the distortion of thethe most advantageous ts the spectralit "sTo find bhe moat absorbatle sector of the spectrum, sometimes enough to use a qualitat've estimate by watching h)%deep the exciting rays of the varlous wave-lengths are penetra-ting a vessel filled with the sulition.
Such an estimate :rbe performed easily as, on Its path of listribution, the excit.rtnlight leaves a distinct, radiant track; The stronger theabsorption, the shorter will be the track. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
j ,, When selecting the wave-length of the.exciting light, o:rethe stokes' part of the spectrum, and in to obtain an intensive radiance,is vital that wave-length of the exciting light was shortershould keep in mind that, accordIng to Vavilov's Law, quantum output of the luaminescence in part It drops sharply.
Thus, it than that of the luminescence spectrum maximum.
According tothe stokes-Lomelle Law. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
According tothe stokes-Lomelle Law.
the above condition is automaticallysatisfied if in the maximum zone of the absorption spectrum.is sufficiently high onlythe anti-stokes'the wav6-A nZths used for the excitation are with-theTHE SECONDARY ABSORPTION.
When,carrying out the analysis,one should take into account that the shape of the specimenluminescence spectrum can be highly distorted by the secondaryabsorption of the luminescence light. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Due to the fact thatthe spectra of absorption and luminescence superimpose eachother (Pig.
187), coming out of the solution depth the lumine-scence light will be partly absorbed by the molecules of thevadisting substance themselves.
This secondary absorption( the"re-absorption") is the superimposition of the spectra, luminescence light in concentration. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
The secondary absorption takes place only inthe zone where the spectra are superimposing each other; thus,the short-waive part of the spectrum will be weakened by thesecondary absorption whereas the long-wave zone will remainunchanged.the more intensive the more accurate isthe substance, and the higher the latter'sthe longer the path of theThin layers of diluted solution are used in order to re-duce the secondary absorption as much as possible. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
However,due to a weak radiance, such conditions are often hard tocreate, and one has to deal with heavy layers of the lumines-cence spectra should be corrected to include the secondaryabsorption, and thus will require time-consuming calculations,the information on the absorption spectrum of the investigatedsubstance, as wall as on the distr!bution of the energy in theTo simplify the calcu-spectrum of the source of excitation. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
lations, it Is disirable to carry out the experiment In sucha way that the rays of the exciting light are fully absorbedthe investigated specimen.When the excitat'on is performed with a continu usspectrum, the frequency J the following luminescence is known:the actual intfenlity of the lumIneacence "lact" inI can be estimated in approximation fromwhen the Aoserved intensity " lo ofs6ruula, 4c (20.1)I, , + a& Cos dwhere: A J -coefficients of absorption of theluminescence and the exciting lightrays, respectively;.function of the energy distributionin the spectrum of the exciting source;S- the refrection angle of the excitinglight In the investigated specimen.The calculatidn will be considerably simplified If a mono-chromatic emission is used for the excitation (only a eingleline is separated from the exciting spectrum). | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
will look as follows:The formals (201)• ...o-..=I oft(120e2)However, neither of the (20.1) and (20.2) formulas providesfor repeated proe~ss of absorption and the resultant excitationof molecules of the luminesoing substance.
At the saw time,during the experiment, ofall radiances formed in for 'Tact" calculated from formulas J20.1) and (20.2) turn outto be not very accuater,the aolution Consequently, the valuesthe luminescence spectrum is a toal 34 I oeA* jMin W ;ForJi AAtAt A if WWS nc 203. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Cur':ea s3hwin(cid:127) F'.
... p se.ýondary luminescence affe.- npe(cid:127),trum thick- spe-r'Im measured as is;layer: b -2 the secondary absorption;3- spectr-,m with correctio.ns for the secondary luminscence..if the flluoresceir .
!
4 A'r: icm.
thick la:er; I f.r r itryri absorp Tor.
ar,dshape of luairnescencea - a 0.1 - spectrum with correctiorns h' .
x,.° im. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
x,.° im.
n -The calculation made on the nbove secondary phenomenareveals that the lumines-en'e speitrum corrected for thesecondary absorption only, !s somewhat shifting towards thelong-waves as against the actual spectrum which Includes boththe secondary and the subsequen'.
radiances.
Fig.
203 showsthe results of calculations for the fluarescein plgment.
can see that with a thin fluorescing layer ence of the secondary radiance (Fig.
203-s0.
this influence becomes more dist1nct (Fig.
203,b). | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Therefore,when working with thin layers of the luminescing diluted solt-tions, corrections for the secondary radiance can be ignored.there, is no influ-In a heavy layEr,OneOf a(cid:127)great importance is also the correct selection ofthe solution concention and of the lumescent layer thickness.If a specimen contains only but little of the substance, theIntensity of the luminescence goes up with the concentration,However, later, a concentration - generated damping actiontakes place and as a result, the radiance intensity of thespecimen drops drastically. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
At the same time, with a higherconcentration, effects the depth of its penetration into the substance, andalso the influence of the secondary absorption will go upsharply.
The most intensive radiance is observed usuplly indiluted solutions whose concentration equals from 10"; up to10"'# moles/liter,the weakening of the exciting light highlyProvided the secondary absorption is either small oe doesit low, is advi-not exist, and the solution conc.entration is sable to work with heavy layers (up to 1 cm.) | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
of the substance,as within certain limits, tne intensity of radiance goes upwith the layer thickness.
However, sible to fully utilize the light coming from so wide lightfluxes; therefore, when the readsngs are expected to be accu-rate, the radiating layer should nat be heavier than 1 mm.When the concentration is intensive, the exciting light doe.not penetrate the solution at all, but is fully absorbed :h at its very surface. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
layers, using just a small amount of the substance to be Lc: s-tigated.seems practically impos-.ase, one can work with In such a it it.
(cid:127).Recording the Luminescence.. Radiance of the investign'- -;specimen is evenly radiating in all directions (Lommelle'l To utilize the emanating light-flux as much as possible, ,ti direct it are being applied.
into the receiver, condenser lens (4) If a spectral devise (6) has been mour.
d t-i(see i,Yaw). | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
d t-i(see i,Yaw).
-.f "he receiver, the lumines- -lux will be 'At.ze(cid:127)• -'.
with Its collimator completelv; "i:ed wit', lig'it; thetelove cond!
'ion can be attained as- byý eans of special 11611-r- 'r:.ating circuits (aee chapter 1?, yt,5).Serious attention should be paid to the selecti.on ufFor example, receivers with antimony-cesiumreceivers which are mostly not the same extent sensitive in'.r.ious parts of the spectrum.
Depending; on the speitral com-pi-sition o!' | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Depending; on the speitral com-pi-sition o!'
the emission, one should select a recelver whosepuak sensitivity would be close to the maximum of the lumine-scence spectrum.
photo-cathodes should be used for' recording a green, blue-violetor ultra-violet luminescence.
Receivers with either multi-alk-aline or oxygen-cesium photo-cathodes are being used for meter-ing the yellow and red luminescence. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Non-selective receiversthe thermo-elements and bolometers are applied for recordinga long-wave red and infra-red luminescence (for more detailson the light receivers see chapter 11, # 45).# Qualitative Analysis of LuminescenceThe problems to which the luminescence analysis is beingapplied are extremely varied; even more varied are the subs-tances subjected to the investigation; consequently, dependingon specific properties of the object to be analized, differentmethods of analysis are being applied. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
However, all the varietyof individual techniques can be grouped in a comparatively smallnumber of methods of a more general mature, which are bei usedin a chemical analysis of luminescence concerning a widestrange of substances.Special Features of a Qualitative Analysis of Luminescence.the problem Is not soBy carrying out a qualitative, chemical analysis ofluminescence, ue can by the radiance spectrum detect the pre-sence of a certain substance, or a group of substances in thespecimen under investigation, and also we can control theprocess of a chern:cal reaction. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
More often than other, thelumneacence analysis is being used for research on tte naturalradiance of the substance.
However, slamle as only few compounds have a distinct, easily regognIzedspectrum of luminesoence by which one can unmistakenly estab-lish the presence of a certain substance (these include: therare-earths and the uranium compounds, porphyrines, chloro-phyll and few others); However, in.
majority og cases, l-mineacence spectra app ar as w~de, washed-out bands withouteny oscillating structure. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
In mt.
(cid:127)urea of two oA more V,(cid:127)Ine-the riesa1on bands of individual componentsscent substances, rf ten superimose one another.
This, thot lumines:ence asali-ale LI easy only when either the m4,xture con!asins ,'zst single luminacent substance or wrien the compone.
's have the'.rrespective radiance In differentparts instance, the red and the blu- racl.ance. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
However, such casesof the spectrum (forthea44C, A 'ir h~ut rarely.USsual~y, priur to perform~ing .being tme atialysis, t.-ý inixt'wrsut.ected to a prelimir.3r:/ ý.-.
'esslng whicnt conasist.-t ellimination of all hampering~ r.grediants and separating,%lie Compinent of a special in~terest tj us.
There are many sr.varled mcthods leadin~g to 8hlich .1 separa,::).r&; varlots uhem4ct-lreactions are here applied., heat.
'ract Oiti on., anc.
also the-%echniques of an ordinary ar~d ttit 1imir1pseenc. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
c-hr.n~atogrnph:.-':he lotter Is more and moro ijsel.,"ne luminescent Chomtora hy represents a variat',n to anordinary chromati,ographicuiet.od of separating the mIxture IntoI.ndividual components; here, the !ndivid'ial zores are beingdetected by watching the luminescence !n the separating them'.olumr.
In~ chose cases when non-lumine-,cent substances arebeing chromatographed,, lumInescing adsorbents are used. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Then.,on the background of a lumineecing coluum, dark strips willc~learly appear over the zones containin~g the nr4 -luminescirng--mtpornents of the mixture.Eq';al'.y Important is Ciae Methcd of Chromnatographing on Paper.A drop of theisoliition to~bi iinve'stigated shall be depositedan a paper strip, close to its bottom; after It has been dried,the strip bottom end shall be immuersed Into a solvent for aperiod of' 6-12 hours. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
The liquid will start rising up thepaper strip; components contained in the drop will follow thesolvent.
The proceed on the paper at a different speed which,however,, is al,,eys lover than that of th~e pare solvent.Quantitatively, the above process ts usually character-ized by the following formula:. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Op (20.3)Where: "A" and "A" distances from the place where the drophas been deposited up to the head of thetravel made by the dissolves 'substanceand the solvent Itself, respectively.The value of R < ; assumlirg the uniform conditione ofthe experiment (ciaf Sr kind of paper, same solvent, saentemperature, etc.
), the above value remains constant for eact,The chromstogran.
wIll show spolts each tied to anocaponent.
Individual c~omnent of the mixture. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Individual c~omnent of the mixture.
All of then .Ustributeciaccording to their respective value for "Ftp".
Position ofthese spots will be established by their charecteriaticfluorescence, In this way, one can detect In a specimen tl'eexistence of as little an one-hundreth of a micro-gram of tneInvestigated substance.
Somettmea, the same goal can be attrgrnel ,Attr.g 6he phosphorence of th,,# s-itstance.
!ýr'-MwthE p.pt.-- the chrimatogram should be :'. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
!ýr'-MwthE p.pt.-- the chrimatogram should be :'.
:- few Be-zrnds -ooled Innitrlrpn, and then subJectel to a shý_Irt exc~tstlun;I!.c:' t:- ormed r~dlance allows esatb1'shing the zones of~ the sub--F";ýrce distributton.
When the ine~tig&Led subatances &nowr, r-adi~nee at.
all, the chrouatogr'ans can be sometlmes success-,'!Iy pro'ePssed In special solut!u~ti' wh~ch make the spots:rniescent.Special.
Techniques ofthe Sualitative AnalIsAs of Luainer.en,:. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
;2"-11:ugh a mIxture has bePrlm..naxrlT separatedWIteten- special procedures are te~ng applied which take Into:o'.
.-nt the special properties of tl~e Investigated Cl13ss Of~':'sanzs*For example, often the luminescence analysis Isterng Carried out at a 'Law temperature when an oscillatingstrxcture appears in the spectrum cof many a compound, a feet-ure which makes the spectrum more characteristic. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
The analysisof ýancerogenjus hydrocarbons of a high molecular weight, isbeing carried out In a viscous medium (in oil) where the struc-ture of their spectra comes out mare clearly, and some otherhanpering factors are eliminated (# 112).L.V. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Shpalskii and his associates, and later also sr'mother scientists have proved that many organic substances(multi-nuclear condensed hydrocarbons, aromatic aldehydes andketones, anthrsquinones, phthalocyanin and its derivatives,as well as some pigmnts) when frozen in the neutral, standardparaffins (pentane, heptane, hexane, etc.)
will have theirluminescence spectra split In groups of narrow lines, whosewidth will very from 2 up to 10 cur 1. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
The appearance of thesecharacteristic lines, permits a fast and reliable detection ofextremely small amounts of the above listed substances In thespecimen.When analyzing a multi-component mixture, one sholild keepin mind that each of the components has Its own spectrum ofabs )rption. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Therefore,, It is advisaible to use the excitationpuipvse,, monochromatic rays of a different wave-length so thates:h of them In exciting juat one of the comporents; tftls pro-2ed'Jre will make "he analysir considerably easier.At low temtperatiues, besides a short-time radiance-fluar-the solution of many a cimpound has ale:) a protract-1es~ence, 3A'ter-rs11anc~e- phosphorence, a circumstance whl-h Is an Imp r-tarnt analytIcal feature of the Investigated substance. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
incase of a B-process, the radiance spectra are clearly thifte.
:towards the long waves In relation to the spectra of fluore-scence, a feature that often helps In analysis of' substanceswith either an ultra-violet or blue luainescence.During a qualit'ttive analys'.s of luminescence, a greathel~p Is desired also fromt the polarization spectra which arestrongly linhiad to the cheulcal structure of the investigote!substances, and In some cases, can be even more indicative51 .,A:'d *'. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
The :pe-ctra of both absorptl ,ompour!4s (Fig.
204).When.
-irrying osut a quall- V-,tive ana>;sls of minerals,11mestones, clays, ceramics, ý I mss, orptical cxystuls, and,,her substances, quite often t:ey meter the curves of the t:iermlc fading-out whose magnl-%ude, position ard number of Maa muma turn out to be suffi- ciently characteristic.
a,_ k(cid:127)Urlne8er. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
a,_ k(cid:127)Urlne8er.
;e ,:' tr.e&%-- - ----- t---"10.1 Z 1"IA f 500 S -,&A,$Despite all the above pro-cPdures, quite often the accuracy of' obtained results remain boubt- ful.
Consequently, after the analysis has been finished, the investigated object is sometimes subjected to additional experi- ments using, for example, the characteristic interdependence uf many substances between the color of their radiance and thevalue of the solution "pH (Fig.186); also, other procedures are being used. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Here, when work-ing out a technique for a luminescence analysis of a giventype of compounds, one should be sure that the addilionalexperiments and procedures are featuring a considerable sensi-tivity Fig.
204. polarizationspectra of the glycerinesolutions of pigments:I- Fluorescein;2- Rhodamine S;3- Acrine orange pigment;Long waves of the excitinglight are plotted on theabscissa axis.but do not consume much time.Luminescent Reactions. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Analysis reactions are widely usedin the practice of chemical analysis; they allow detectingcertain substances by a changed color of their solution, bythe sediment formed, or by other characteristic symptoms.
Theluminescent reactions are one of the types of analytical reac-tions. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
They are characterized by a change the luminescenceproperties of the substance; during the reaction, the lumines-cence spectrum of the investigated object becomes deformed,the radiance either fades away, or becomes brighter.in Luminescent reactions can be performed also on sutbstar.
(cid:127)esIn such cases, th- re-which have no luminescent capability.
action is being conducted in such a Xay that, after It ha. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
terminated, should be thoroughly studied, and the "ond~t~onin which the analysis will be carried out, should be rig.dlysatndarized..-.# 109, The quantitative Analysis of Luminescence.A quantitatlve analysis of luminescence allows establishingthe concentration of the Investigated substance In the sample,by metering the brightness of Its radiance; It also revealsthe termination of the reaction by the luminescence having .. ppeareu. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
It snoild be n~ a qualitative and a qtant.tatlve rz.ed ,,.,(-en ",.ce consists in analysis of lumines-the fact that the features just detected b;.it that !he maln dif.
:'e:,qualltative analysis, i:,,ý pro:ýeased with(cid:127) all necessn.-y ý_.
:.-rrectlons considered.in' a a-ient'tative snalysJs are measuredX11 Me'hod Quantitative Analysis of L=1mr.escen~e Based on the .ladinJnco,conce;.-nnrr/. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
this type of anal~ysis are,One should try to carry oitt the analysis in conditions...r.1wh tne s s. 1.nseýl on a ..ertain definite interdependence between the brl;7,t,-.-,ess of the radiance and the substance concentration In (cid:127):ample.
p:.oviding a straight proportion between these two factors.
tne concentration of the investigated substance can be deter-.. ned by directly comparing the radlance intensity of the 3.i-lyzed specimen with that of a standard pne. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
When the concen-tration is considerable, over 10'(cid:127) - 10- moles/liter, thec-traight proportion is usually upset in Ing action created. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
By the excessive concentration.result the'of the extinqulsh-In general, the quantitative analysis of luminescenceconsists of preparation of a set of standard specimen contain-ing a known concentration of the substance investigated, andof measuring the intensity of their obtained data will be used for plotting an analytical curveshowing the luminescence intensity as function of the concen-tration.
Having measured the radiance intensity of the analyzedsample. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
From the analytical curve we can establish theconcentration of a substance in respective radiance.
the sample.TheIn the quantitative analysis of luminescence, usually thenatural radiance of the investigated substance is being utilized.When working with non-luminescing objects, are being applied and by the radiance intensity of the recul-tent product, its concentration can be determined. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Next, byusing the conversion methods well known in Themistry, one can determine the concentration of the Init*lilproduct of the said reaction.the analyticalluminescent reactionsFor example, to determine the amount of oxygen in inc:r.should be passes through a solution of.,ases, the latter ý:olorless Leuco Base 4 of the fluorescein pigment; the so!,uionwill oxidize, change into fluorescein which, in solution, h(cid:127),(cid:127),an intensive green luminescence. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
ffeving compared the In1.rtrr, of the formed radiance with that of the solutlon lumin:-Rc-r,we can determine the concentration of fluorescein which :' in the process of the reaction.
Simple calculations allowestablishing the amount of oxygen passed through the aolu,..'(cid:127)ii,and that had oxidized the necessary amount of the Leuco Base. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
".t* The leuco Bases are products of regeneration of some pgr,.wn.swhich, as a rule, are colorless.53 ItQuite often, an analysis cannot be successfully carrIedout due to the fact that the radiance intensity of the Inves-tigatel substance can be determined not just from its concen-tratlon but also from a number of other factors. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
For example,the radiance intensity of a solution is being affected by:various processes of fading-out; absorption of a certain part?f the exciting light by foreign admixtures; the secondary absorption of luminescence; etc. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Therefore, when working outthe technique for analysis of different groups of compounds,,one should thoroughly investigate the nature of processesswhich might take place in solutions of these substances.To receiveWhen carrying out an analysis, one should, first of all,follow all the rules concerning the excitation and the recor-ding of radiance, as it has been described in #107. reliable results, it Is of great importance that both thestandard and the investigated specimens were during the analysissubjected to rigidly similar conditions (excitation from thesame source; an exactly the sam position in the appratus; bothsolutions in vessels of the same wall thickness, with a partlyabsdrbed light of excitation; etc.). | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Moreover, that the spectral composition of radiance of either specimenwas the same.
For this purpose, the standard solutions of thevery substance whose concentration we are about to investigate,serve as the standard.
tc prepar this kind of solution (instability of solutions, etc.
)one can use standards of other substances instead, whose radianceby its spectral composition is similar to that of the investi-Preliminarily, these standards should be gradu-gated sample. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
ated by the investigated substance solution whose concentrationis known. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Occasionally, the standards are consist of some typesof luminescent glass (uranyl, and others) which are not subjectto photo-chemlcal transformations, and emit a radiance constantin time.In those cases when it impossibleIs vitalis it The analysis results can be considerably distorted byAIter) If existenre of extinquishing ingredients in the sample.ellminate their interference, diluted solutions (C "'lO-rmoles/the above method is not effective:hould be prepared so that the concentration of thoseIn"redlrts becomes negligible, and they will stop affectingthe rndrV.Ance itself. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
C; ough., cone can compose standard samples using the same mul lti-com-pooeara solvents which are contained in the specimen about toLe siaiyzed.
In case neither the composition of analyzed solu-tion nor the concentration of the foreign admixtures are known,a certain amount of the investigated substance should be audecto the investited solution. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
By comparing the radianci !,Aten-sity of the 6btolned mixture with that of the original soltlou,one can evaluate the extinquishing capability of the foreignIngredients.
it In the analysis of substances with either basic or acidthe a Wnitude of "pH" greatly affects bothcharacteristics, the spectral composition and the radiance intensity.
Themagnitude of "pHe determineo the condition of molecules in asolution; they can appear there either in a non-ionized stateor as Iona with opposite electr:c charges. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Here, the radiance.intensity of each of the molecule type can be .extremely varied.For example, molecules of a weak base of acridine in analicaline medium (VHw-lO) When the value of pH" goes down, Into an Ionized state, forming molecules of acridine (21). | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Inthe fifth normal HCL, remain in a non-ionized condition (T).the process will be completely terminatedtthe will gradually changsH+At the same time, &25 a ) It will turn into greenAs a result, the spectral composition of the radiancewill change; foP an alkaline solution In the acid md6m, froma vlolet-blue (4 s- (ka,; 475 a " will--op to less than one-half. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Therefore, it often be-omsnecessary to deal with the so called, "Buffer Solutionse; isan alternative, one can utilize the circumstance that startingwith a certain valve of "pH" of the solution, molecules of suchcompositions stop reacting to any change in of hydrogen ions. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
of alcoholic solution of the 2,- amlnoacridine will stop changingpH" goes up to more than pH--ll.noticeably when the value of This kind of substances are being analyzed In solutions whose"pH" Is beyond the above limit.the luminescence spectrathe radiance intensitythe concentrationSo, for example, Above, we have Indicated only the main factors which affectthe accuracy of the quantitative analysis of luminescence. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Onthe other hand, eash of the investigated substances has Its ownspecific properties which should be taken into account whenworking out the technique for Its analysis.
* A buffer solution is a solution of salt, the salt and acid,or dalt and alkall magnitude when either the concentration has been changed orin which the "pH* does not change itssacd or alkalis added In an amount below a certain limit.55 A Quantitative Luminescence A:i;lysas of the Terminationof' %he3ilcal Reactions. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
This type of analysis concerns also themethod of luminescent titration.
Thia method consists ofgradually adding small amounts of the substance-reagent froma buret into the investigated lumlnescent solution.
Thereagent Is selected in such a way that after it had enter theit w'll form a compound which no reaction with the substance, luminescent properties.The reagent is being adaed for so longuntil the solution radiance will stop completely. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Knowing theamount of reagent necessary for turning the Investigated sub-stance into a non-luminescent composition, by conversion wecan determine its contents in the resultant solution.
Theabove method presents a modification to the usual ones ofchemical titration. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
The difference consists only in the follow-ing: in the luminescent titration, the process termination Isbeing noted by the disappearance of its radiance, and not bya change in the solution color or by its having become cloudy.The *;In advantage of the luminescent method consists in high sensitivity, a feature which makes Ing out an analysis on highly diluted solutions.it suitable for carry-its|In those cases when the process of radiance extinquishingby foreign mixtures has been thoroughly studied, this methodcan be also applied for a qualitative analysis. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Here, lution concentration can be evaluated by the degree of theradiance fading-out which will take place after a certainamount of a specially adapted extinquisher, will be added tothe analyzed solution.the so-The special features characteristic to the luminescenceof a number of organic substances with their either acid orbasic properties, allow a widespread use of luminescent Indl-catorB into the practice of chemical procedures. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Their pur-pose similar to that of the ordinary indicabors, indicating the end point of a chemical reaction or determiningthe concentration of hydrogen ions (the value of "pH") in thesolution (table 38).
The luminescent indicators differ fromthe ordinary ones in that at the end of a certain process,nottheir color will change but either their spectral compositionor the intensity of their luminescence (Fig.
186).is either56 TAS.~ L9 -3 .-9 W"" I~PH 2. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
186).is either56 TAS.~ L9 -3 .-9 W"" I~PH 2.
New or~muis -IbmminmIndicator;__________ ____________3.tructuralformula;fluorescence cnChange, or the6, 14- ozyacrlcloie;7Orzem-Blue;ID.
naghthylesine;l 0.
Acridine;Oraeon-violet;12.
3-mathyl umbelli-ferozne;13.
Wane-Blue;15.
Gree-Blue;Chicago-CC-ac 1d;17 Violet-Green;18.
1.
5-naphthylaainte-sulto-sc 14;19, Blue-Green.40 * Qi 31"184* (Yr' 4.64.611, o P u,.i.~5*..7* ______1"16 ~16. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
""off57 WAThanks to the luminescent indicators we obtain a cleartheir concentration In a solution Is very smll.effect even if They are irreplaceable for the analysis of dark colored orturbid medium (wine, oils, solutions of salts of some non-fer-rous metals, etc.)
where the ordinary indicators are hardlyuseful as their chanme of color cannot be noticed.
At present,about 200 acid-basic luminescent Indicators are known whichcover the entire posaible range within which the solution "pH"can vary. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
They are the derivatives of Benzene, naphthalene,comrIn, fluorescein, acridine, and other compounds.
Mostof the indicators display a blue-green radiance.
Table 38 listssow of the more widely used acid-basic indicators.red luminescence. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
(pH - 3-3.6 ); mide Considerable lees is known about indicators with a yellow-W* could name here: the dimethylnaphthorhodinethe neutral red (pH - 5-7.4); 3.6 - dioxyphthala-(pH = 6-8); and the acridine orange (pH - 8.4-9.2).Working with luminesoent indicators can become quite complexwhen the absorption spectrum of the analyzed specimen will super-impose itself on the luminescence spectrum of the indicator; then,the indicator radiance will become partly or fully absorbed. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Toprevent this, for each interval of the "pH" values, two indica-tors are being selected with luminescence of different colors.By using them one after another, we will obtain a correct re-suit of the analysis.In some rare cases, chemi-luminescent indicators are beinglucigenine, used (Luminol, liphine, slloxen) whose performanceis based on formation of a chemi-luminescent radiance when the"pH" value of a soll,.tlon will change, and also when any kind ofan oxidizer will appear in it. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Their main superiority over theluminescent Indicators consists In the fact that when workingwith them there Is no need to subject the Investigated solutionto ultra-violet rays.
To obtain rliable results, the analystsshould be carried out at a certain constant temperature whichhighl affects the process of the chemi-luminescent reaction.110 Polarization Methods of the Luminescence Analysis.Saklmes a qualitative an quan _tative analysis or the&ubstance composition, the luminescen. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
methods aid in solvingmny other important problems associated with the structureanalysis of complex molecules and crystals.
Particularlypromising in this respect are the polarization methods. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
applying them, one can: determine a matual disposition of theabsorbing and emitting oscillators in molecules as well as theorientation of emitting oscillators In relation to the mole-u-lar axes; establish the relation between the symmetry of mole-,cules and the polarization; determine the multi-polarity ofelemntary emitters of the molecules; and also measure thevolum of investigated lolecules and the duration of theirradiance.By58 Deterunim the Mutual DiSRosition of Absorbin andmolcoOes canbhviour r? | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
real _____________tor.n be approximste by analy&ing the performance of various typestoXtlD the molecules can be linkedof elementary emitters to linear oscillators (dipoles).
V. L. Levsnin and P. Perrenhave established that the degree of luminescence polarizationis a function of angle * " between the oscillator of emissionand that of absorption, and can be presented in the followingformula -tP.+;n (2o.
'lIt turned out that the degree of polarization depends onthe wave-length of the exciting light. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
This interdopsdencewas thoroughly studied by Vavilov who qalled it o)pekaftablmonspectrum, He demonstrated that, when X j goes down.
degree of polarization will drop drasticilly, frequently evenchanging its sign; later, It will go.
'up again and somstimasreaches a second nmuaii.
that is a certain relation between the polarization spectra andthose of absorption (Fig.
205).P.
P. Feofilov has established thatThegt -too ---r-Ifn--1--A a ain A W W4qPig.
205. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
205.
Polarization spectra (top curves) and spectraof absorption (bottom curves) of pignt celnj b- Rhodamine B extra; c- acrIdine orange.solutions: a-fluores-Within a single band of absorption the degree of polariza-tion does not change such.
This mwma that each electrorictransition is matched by its own absorption oscillator.
Coeid-erIng that the individual bands of absorption superiMose each59 Iother, transition from one value of polirization to anotherproceed continuously. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Having measured the degree of the lumines-cence polarity when excited in different zones of absorption,by formula (20.4) one can establish the relating disposition ofthe oscillators of absorption and those emission in the inves-tigated uolecqles. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Polarization spectra were used for theresaarch on the structure of nume:ous organic compounds (naph-tnalene, antrtcene and its derivatives, polyenes, porphyrina,chlorophyll, etc)Another Important problem whicn so far tas been solvedbut few compounda, is establishing the orientation ofabsorption oscillators in relation to tne molecular axes.then the other can be deter-In the case of molecular mono-crystals, the polarizationof luminescence can be determined by boLh orientation of theesmisson oscillator In relation to the molecule axes, and byorientation of the molecule itself in the crystal lattice,If one of these factors Is known, min(cid:127)ed by the polarization of radiance. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
Thus, by the orienatic, nof molecules In the lattice of mono-crystals of naphthalene,antracene, stilbene, and other compounds.
By having measuredtne luminescence polarization of the above crystals, we coulddetermine the orientation of tneir emitting oscillator in rela-tion to the molecular axes. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
On the other hand, naving comparedthe polarization ans absorption spectra of the solutions, wecan establish the orientat'.on of the oscillators of absorptionand emission, respectively, Next, having measured the polarization diagrams (see below),we can determine tne orientation of molecules In the crystallattice. | https://docs-lawep.s3.us-east-2.amazonaws.com/1709799757321.pdf | https://apps.dtic.mil/sti/pdfs/AD0632799.pdf | Central African Republic |
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