url
stringlengths 15
1.48k
| date
timestamp[s] | file_path
stringlengths 125
155
| language_score
float64 0.65
1
| token_count
int64 75
32.8k
| dump
stringclasses 96
values | global_id
stringlengths 41
46
| lang
stringclasses 1
value | text
stringlengths 295
153k
| domain
stringclasses 67
values |
|---|---|---|---|---|---|---|---|---|---|
https://transmissioncoolerguide.com/transmission-coolers/how-does-a-transmission-cooler-work/ | 2024-04-12T11:05:21 | s3://commoncrawl/crawl-data/CC-MAIN-2024-18/segments/1712296815919.75/warc/CC-MAIN-20240412101354-20240412131354-00354.warc.gz | 0.946885 | 394 | CC-MAIN-2024-18 | webtext-fineweb__CC-MAIN-2024-18__0__82792890 | en | Transmission coolers are designed to disperse heat from the hot fluid flowing through it. For example, a tube and fin style transmission cooler has fins throughout the body of the cooler to help heat escape the tubes.
The incoming air, which is at a lower temperature than the fluid in the cooler helps the fluid cool down before going to the transmission. Air flow is on of the biggest factors in allowing your transmission cooler to do its job, as long as it is placed in a spot in front of the vehicle.
Because of this, most vehicles can benefit from mounting the transmission cooler in front of the air conditioning condenser or radiator to get as much incoming air as possible, and use the cooling fans when at idle.
If you are in a situation where you cannot use a cooler in front of the car where it can get enough air flow, it is recommended to use a cooler with a fan. Most common cars will not need to deal with a remote mounted transmission cooler with a fan based on the simplicity of most cars.
Another reason a transmission cooler stays cool is because it is independent of the cooler in the radiator. Factory transmission cooler are mounting inside the vehicle’s radiator. While this is fine for most situations, the transmission fluid will often run hotter. The hot coolant in the radiator can sometimes increase transmission temperatures, and almost act like a heater. It is not uncommon to see temperature drops of 20-30 degrees after installing an transmission cooler.
Transmission coolers are able to stay cool because they utilize air flow that passes through the cooler, which is colder than the fluid running though the cooler. The air passes through cooling fins or plates where the cooling flows and can cool very efficiently.
Also, the fact that external transmission coolers are mounted outside of the radiator helps them just cool transmission fluid. Transmission fluid in a radiator can be noticeably warmer because it shares surface space with the engine’s hot coolant. | physics |
https://www.queenstreetchiropractic.ca/diagnostic-imaging/ | 2024-02-22T17:43:47 | s3://commoncrawl/crawl-data/CC-MAIN-2024-10/segments/1707947473824.13/warc/CC-MAIN-20240222161802-20240222191802-00583.warc.gz | 0.94581 | 1,038 | CC-MAIN-2024-10 | webtext-fineweb__CC-MAIN-2024-10__0__206112480 | en | Dr. Korey Jay BSc DC
Diagnostic imaging has improved by leaps and bounds since the development of the first radiographs over one hundred years ago. In 1896 Wilhelm Roentgen discovered and pioneered the study of radiology, and in certain parts of the world radiographs (x-rays) are still referred to as “Roentgenographs” in his honour. Prior to the discovery of radiographs, health care practitioners had to rely solely on clinical findings to establish a diagnosis. Now there are a wealth of imaging tests to aid in the diagnosis of a variety of conditions or anomalies, this post will attempt to differentiate some of the types of imaging available and what types of conditions they are best used for.
The basis of radiography is that certain forms of radiation will penetrate different materials at different strengths. For instances, x-rays will easily penetrate soft tissues such as skin and muscle, but will not be able to penetrate bone or metal as easily. Armed with this knowledge, one can use the differences in the penetrative power of the x-ray to create an image of the body. Radiographs are of particular use as a scanning tool, as they are quick and easy to obtain. However, there are some drawbacks to radiographs. As radiographs produce a two dimensional image, it is necessary to take at least two radiographs at perpendicular angles to one another in order to get a sense of the three dimensional structure “One View is No View!”. Radiographs are also relatively non-specific or sensitive. Cancerous processes of bone, for instance, often require nearly 60% progression of damage until they show up on a regular plain film radiograph. Also, radiography utilizes ionizing radiation which can cause cell death or other damage and thus must be employed judiciously.
In order to compensate for the lack of sensitivity or specificity of the regular plain film radiograph, the CT Scan was developed. A CT, or “Cat Scan”, is essentially a three-dimensional radiograph. Employing a circular or tube-shaped apparatus, the CT Scanner basically takes a series of 360 degree radiographs to obtain a “slice” of the body being examined. This technology was a great leap forward, and has advantages of being quick and quite specific. The disadvantage of ionizing radiation still exists, however.
As any expectant mother will tell you, ultrasound is a powerful and amazing tool. In place of ionizing radiation, ultrasound utilizes ultrasonic frequency sound waves, which have the ability to penetrate tissues to produce an image. Ultrasound is useful as it is not damaging to the individual, it produces an image in which one can also view the soft tissues (muscle, joint, ligament etc. which are not easily read on a radiograph) and the images may be obtained quickly. This allows ultrasound to be employed to assess the abdominal contents such as the organs of the body in an efficient manner. As with radiographs however, ultrasound technology does not produce a clear image, which results in a lack of sensitivity.
Magnetic Resonance Imaging (MRI):
MRI is the gold standard of imaging, and the only way to produce a more clear, sensitive and specific image is to actually biopsy a tissue (Biopsy=cutting out a section of tissue to look at under a microscope). The basic concept of MRI is that the cells and tissues of our body create a net magnetic “spin” or “direction” due to the inherent polarity of the nuclei of the atoms they are composed of (confusing? Tell me about it!). Without getting in to nuclear physics too much, MRI works by applying a hugely powerful magnet to knock the body’s magnetic polarity off-kilter. When the magnet is turned off, a scanner in the machine registers the “Resonance” of the body’s tissues as they return to their resting state. While confusing, this triumph of physics results in a crystal clear image that may be viewed three dimensionally and is safe to the patient. Drawbacks to MRI are long waiting times, you may not have MRI if you have any metal in your body (it is a giant magnet, think about it!) and it can be a long, noisy and somewhat claustrophobic environment.
Chiropractors are trained extensively in utilizing every type of diagnostic imaging to reach a working diagnosis for our patients. We at Queen Street Chiropractic Centre believe that imaging is to be employed only when there is some uncertainty or suspicion of underlying factors, or if there has been trauma to the area of concern. A proper and thorough medical history and physical examination is still the preferred method of diagnosing the patient’s complaint. However, if necessary the Doctors at Queen Street Chiropractic Centre will refer for diagnostic imaging, and will be more than happy to sit down with a patient to assess the images and discuss the findings and what options are available to the patient.
Feel free to book an appointment at Queen Street Chiropractic Centre today! | physics |
https://www.frightprops.com/props/halloween-decorations/industrial/blue-gauge.html | 2021-07-24T13:17:42 | s3://commoncrawl/crawl-data/CC-MAIN-2021-31/segments/1627046150266.65/warc/CC-MAIN-20210724125655-20210724155655-00049.warc.gz | 0.957314 | 151 | CC-MAIN-2021-31 | webtext-fineweb__CC-MAIN-2021-31__0__230115944 | en | We have several products that light up: gauges, electrical panels, vacuum tubes, etc. None utilize real glass but instead a clear resin, so there’s no shatter hazard. All are illuminated with 12-volt DC LEDs and can be run on 9 15-volt DC for safe and efficient use. You can even use a 9-volt battery for several days in a row of operation. LED lights last a long time, 50,000 hours is expected, though many go much longer than that.
You can power the LEDs with a 9V to 12V battery. We have a 12V battery pack here that can power several of these products at the same time. You can also power this product with our 12V power supply. | physics |
https://aiexpress.io/scientists-developed-a-new-quantum-tool-in-a-groundbreaking-experiment/ | 2022-12-07T07:30:05 | s3://commoncrawl/crawl-data/CC-MAIN-2022-49/segments/1669446711150.61/warc/CC-MAIN-20221207053157-20221207083157-00025.warc.gz | 0.916504 | 607 | CC-MAIN-2022-49 | webtext-fineweb__CC-MAIN-2022-49__0__124888308 | en | A tool design utilizing neutrons has by no means earlier than been efficiently confirmed, regardless of methods for the experimental synthesis and examine of orbital angular momentum in photons and electrons being extensively researched. Neutrons have distinctive properties, subsequently, the researchers needed to construct new instruments and develop contemporary approaches to working with them.
Scientists on the Institute for Quantum Computing (IQC) have developed a tool that produces twisted neutrons with clearly specified orbital angular momentum for the primary time in experimental historical past. This groundbreaking scientific achievement, which was beforehand thought inconceivable, gives a brand-new method for scientists to research the expansion of next-generation quantum supplies, with functions starting from quantum computing to discovering and resolving novel issues in basic physics.
Dr. Dusan Sarenac, a analysis affiliate with IQC and technical lead of Transformative Quantum Applied sciences on the College of Waterloo, stated, “Neutrons are a strong probe for the characterization of rising quantum supplies as a result of they’ve a number of distinctive options. They’ve nanometer-sized wavelengths, electrical neutrality, and a comparatively giant mass. These options imply neutrons can go by way of supplies that X-rays and light-weight can’t.”
IQC and Division of Physics and Astronomy school member Dr. Dmitry Pushin and his group constructed small silicon grating buildings resembling forks for his or her research. These gadgets are so minuscule that greater than six million fork dislocation part gratings may be present in solely 0.5 cm by 0.5 cm. The person neutrons begin twisting in a corkscrew sample as a stream of single neutrons passes by way of this machine. A specialised neutron digicam recorded the neutrons’ footage after they traveled 19 meters. The group seen that each neutron had grown into a ten cm broad donut-shaped hint.
The donut sample of the propagated neutrons signifies that they’ve been put in a particular helical state and that the group’s grating gadgets have generated neutron beams with quantized orbital angular momentum, the primary experimental achievement of its variety.
Dr. Dmitry Pushin, IQC and Division of Physics and Astronomy school member at Waterloo, said, “Neutrons have been well-liked within the experimental verification of basic physics, utilizing the three simply accessible levels of freedom: spin, path, and power. In these experiments, our group has enabled the usage of orbital angular momentum in neutron beams, offering a further quantized diploma of freedom. In doing so, we’re growing a toolbox to characterize and look at difficult supplies wanted for the subsequent technology of quantum gadgets comparable to quantum simulators and quantum computer systems.”
- Dusan Sarenac, Melissa Henerson, et al. Experimental realization of neutron helical waves. Science Advances. DOI: 10.1126/sciadv.add2002 | physics |
http://web.student.chalmers.se/~josefj/Fieldstation2.html | 2020-01-18T20:28:34 | s3://commoncrawl/crawl-data/CC-MAIN-2020-05/segments/1579250593937.27/warc/CC-MAIN-20200118193018-20200118221018-00045.warc.gz | 0.930244 | 651 | CC-MAIN-2020-05 | webtext-fineweb__CC-MAIN-2020-05__0__36893031 | en | Field station in Östersund
In 2017 a test site for hydronic heated pavements (HHP) was constructed outside Östersund (63.18 N, 14.5 E) in Sweden. The test site is part of a Nordfou project named HERO (Heating Road with Stored Solar Energy) and the major founders are the Swedish, Norwegian and Finnish public road administrations. The aim of the test site is to investigate and prove the concept of using hydronic heated pavements with stored solar energy. The hydronic pavement is used for preventing slippery road conditions in the winter and as an asphalt solar collector in the summer.
The main challenges are set by the harsh Scandinavian climate. The climate puts special demands on how to utilize the limited energy that has been harvested. This is handled by a low temperature system working with supply temperatures below 10 °C.
The figure below gives a general description of the test site. There are five major components namely the weather station, the service building, the borehole thermal energy storage, the hydronic heated surface and a reference surface. The energy used by the system is stored in the BTES that is made of 4 boreholes with a depth of 200 m. Each borehole contains a single u-tube thermal collector. The service building house all the measuring equipment and pumps required for the system. In the service building there is also an electric boiler as backup. The weather station provides the information on the local weather (Air temperature, RH, Wind, Precipitation, Camera) for both controlling and evaluation of the measured results.
The testbed for hydronic heated pavements is constructed with a top layer of concrete that contains the pipe placed at a depth of 62 mm (pipe center) and with a spacing of 50 mm (The three outer most have a distance of 40 mm). Further down the HHP is made as a regular road but with an insulation layer as protection for frost heave but also giving more stable boundary conditions for the numerical simulations. The pipes are made of cross-linked polyethylene (PE-Xa) with the dimensions of 20x2 mm. 10 pipes are going back and forth in the concrete giving a total length of the pipes of about 140 m. The pipes are covering an area of 70 m2.
The measuring system consists of one logger unit coupled to four multiplexers which increases the number of input signals to 80. Today about half of them are used. The core unit is a Datataker 85M which logs readings every 10 minutes. This unit can handle a wide set of different sensors. The data gathered by is transferred to the main computer that handles the control system for the hydronic pavement. To the main computer is the weather station connected. In addition, are two surface state sensors (Vaisala DSC 111) connected that estimates the surface conditions based on optical methods. These sensors provide estimates of the friction level, water-, ice- and snow thickness. Two sensors are installed, one for the heated surface and one for the reference surface. For measurements in the pavement structure PT100 sensors are used. The sensors used are Pentronic 7912000 PT100 1/5 DIN.
Back to main page | physics |
https://presidentwater.co/products/homecare-lite-pw38-3-8-10mm | 2023-09-29T14:31:10 | s3://commoncrawl/crawl-data/CC-MAIN-2023-40/segments/1695233510516.56/warc/CC-MAIN-20230929122500-20230929152500-00318.warc.gz | 0.828238 | 159 | CC-MAIN-2023-40 | webtext-fineweb__CC-MAIN-2023-40__0__205178110 | en | Homecare Lite PW38 - 3/8" - 10mm
Introducing the PW38 vortex generator for 3/8 in. (10mm) lines.
Three years in the design, development, testing, and making, the PW38 is an innovative, first-of-its-kind vortex generator that brings energized water to entirely new sectors.
Weighing less than 1 lb (0.34 kg), and 7" (180mm) long, the PW38 can be deployed to energize water in many areas, including:
- Shower wands
- Water vending machines
- Aquariums / Ponds | physics |
http://www.trenkwalder-sks.com/leak-testing-features-for-all-industries/ | 2020-08-06T07:01:47 | s3://commoncrawl/crawl-data/CC-MAIN-2020-34/segments/1596439736883.40/warc/CC-MAIN-20200806061804-20200806091804-00295.warc.gz | 0.94848 | 353 | CC-MAIN-2020-34 | webtext-fineweb__CC-MAIN-2020-34__0__144570722 | en | Reliable burst and proof pressure testing is being applied where relevant. It has been influenced by all research and development, and manufacturing work that comes out of the leak testing houston tx factory. In that same voice, industries in which research and developmental work predominates, as well as manufacturing, will have a high dependence on the capacity for testing for leaks in cylinders, pipes, valves and so many other vital parts and components of different sizes, from the smallest handheld object to those as large as a football field.
It is necessary for all testing equipment to be of a known quality in order to do justice to the testing work ahead, thus helping to ensure reliability and integrity. A range of testing services are being provided to help determine proof pressures and other pressure types. Testing devices can always monitor low pressures. But they can also take measurements as high as 200,000 psi. typically, 7 psi glass chemical vessels and 200,000 psi steel tubes will be used respectively.
Also, a variety of materials will be utilized, amongst which include, compressed air, helium, liquid and nitrogen.
Test transducers are designed to cater for all pressures and need to be certified to the standards set by the NIST. Instrumentation fabrications will vary in accordance with the testing environment. This varies from the manual recording of data to high speed multichannel computer based data logging.
Proof testing and leak testing are closely related. Proof testing is non-destructive. It is able to determine that a system or component is able to withstand pressures slightly above operating pressures without permanent damage or leaks occurring. The checking for leaks requires a part to be immersed in a clear liquid. This simple test can be taken to a higher level, using a spectrometer and helium. | physics |
https://emunahrooted.co.za/products/crave-scientific-coffee-machine | 2022-08-07T21:30:36 | s3://commoncrawl/crawl-data/CC-MAIN-2022-33/segments/1659882570730.59/warc/CC-MAIN-20220807211157-20220808001157-00590.warc.gz | 0.949562 | 220 | CC-MAIN-2022-33 | webtext-fineweb__CC-MAIN-2022-33__0__162184152 | en | A manual brewing method that goes back as far as the 1930s and is still one of the preferred brewing methods today! It's not just water flowing from the one chamber to the next. The Scientific Coffee Brewer works on a heat and pressure principle that is crucial for a great tasting cup of coffee. Water reaches boiling point at 100 degrees Celsius. When it reaches that temperature it starts to evaporate into steam. Due to pressure and temperature change in the flask, steam quickly condenses to water as it travels via the copper tube system into the coffee placement vase. Temperature is at approximately 90 degrees Celsius upon contact with coffee. After brewing for about 30 seconds heat is turned off and a vacuum is created allowing coffee to flow back. Giving you the perfect cup of coffee!
Brewing time is just under 7 minutes.
Brewer can make approximately 30+ Brews on a single gas cartridge.
Gas cartridges are highly available at most retail stores nationwide.
For the name engraving option, please email what you’d like engraved to [email protected] | physics |
http://billnelsonauto.com/overheating.html | 2018-02-20T19:37:25 | s3://commoncrawl/crawl-data/CC-MAIN-2018-09/segments/1518891813088.82/warc/CC-MAIN-20180220185145-20180220205145-00435.warc.gz | 0.927618 | 466 | CC-MAIN-2018-09 | webtext-fineweb__CC-MAIN-2018-09__0__116238368 | en | Overheating can be caused by anything that decreases the cooling system's ability to absorb, transport and dissipate heat: A low coolant level, a coolant leak (through internal or external leaks), poor heat conductivity inside the engine because of accumulated deposits in the water jackets, a defective thermostat that doesn't open, poor airflow through the radiator, a slipping fan clutch, an inoperative electric cooling fan, a collapsed lower radiator hose, an eroded or loose water pump impeller, or even a defective radiator cap.
One of nature's basic laws says that heat always flows from an area of higher temperature to an area of lesser temperature, never the other way around. The only way to cool hot metal, therefore, is to keep it in constant contact with a cooler liquid. And the only way to do that is to keep the coolant in constant circulation. As soon as the circulation stops, either because of a problem with the water pump, thermostat or loss of coolant, engine temperatures begin to rise and the engine starts to overheat.
The coolant also has to get rid of the heat it soaks up inside the engine. If the radiator is clogged with bugs and debris, or if its internal passages are blocked with sediment, rust or gunk, the cooling efficiency will be reduced and the engine will run hot. The same thing will happen if the cooling fan is not engaging or spinning fast enough to pull air through the radiator.
The thermostat must be doing its job to keep the engine's average temperature within the normal range so the engine does not overheat. If the thermostat fails to open, it will effectively block the flow of coolant and the engine will overheat.
Exhaust restrictions can also cause the engine to overheat. The exhaust carries a lot of heat away from the engine, so if the catalytic converter is restricted, or a pipe has been crimped or crushed, exhasut flow can be restrricted causing heat to build up inside the engine.
It's also possible that your engine really isn't overheating at all. Your temperature gauge or warning lamp might be coming on because of a faulty coolant sensor. Sometimes this can be caused by a low coolant level or air trapped under the sensor. | physics |
https://www.goodwestlining.com/hi-temp-coatings.php | 2024-02-26T15:16:44 | s3://commoncrawl/crawl-data/CC-MAIN-2024-10/segments/1707947474660.32/warc/CC-MAIN-20240226130305-20240226160305-00895.warc.gz | 0.891053 | 246 | CC-MAIN-2024-10 | webtext-fineweb__CC-MAIN-2024-10__0__11385768 | en | Protective Hi-Temp Coatings
Goodwest applies materials that are resistant to extreme chemical and temperature environments. Rubber linings, Fusion Bonded Epoxy, and Novolac Epoxies are used for high temperature immersion environments up to 270 deg. F, depending on the chemicals involved.
There are several coatings available that resist much higher temperatures in primarily dry environments. The most commonly used material on steel for high temperatures is a single-component silicone aluminum acrylic. The silicone provides excellent elasticity to handle the expansion and contraction of steel. The aluminum pigment offers greatly enhanced temperature resistance over other colors.
Hi-temp coatings are often used on the exterior of exhaust ducts and other process equipment that will have internal temperatures from 300° — 1,000° F. Other protective coating materials degrade rapidly when steel temperatures get near 300 deg. F. Hi-temp coatings like silicone aluminum acrylic can withstand the temperatures and thus provide long-term corrosion protection against UV, ozone, and other external conditions. Contact us now to engineer and install a protective coating system that will lengthen the lifespan of your equipment.
Contact us for your protective coating needs. We will ensure your critical equipment lasts as long as possible. | physics |
https://samb2.space/sam/components/reduced-gravity-simulator/ | 2024-02-29T10:51:34 | s3://commoncrawl/crawl-data/CC-MAIN-2024-10/segments/1707947474808.39/warc/CC-MAIN-20240229103115-20240229133115-00182.warc.gz | 0.933984 | 342 | CC-MAIN-2024-10 | webtext-fineweb__CC-MAIN-2024-10__0__110411190 | en | Since the early 1960s NASA has employed reduced gravity walking simulators and gravity-offload rigs to provide astronauts with training for movement in reduced gravity and micro-gravity environments. While we cannot reduce the actual gravitational pull of the mass beneath our feet, we can simulate to varying degrees of accuracy, the effect of a reduced or fully diminished field of gravity and how it affects our ability to maneuver across varied terrain.
Reduced gravity simulators were used in training the Apollo astronauts to learn how to walk on the Moon before arriving. They discovered that a “bunny hop” or skip was the most effective means of travel by foot as normal walking was impaired by the cumbersome nature of the massive pressure suits. Hollywood too uses gravity-offset rigs to simulate space walks, movement in micro-gravity, free-fall, and martial arts fights in which a powerful punch sends someone spinning through space.
Here are two examples of how NASA has used similar rigs for research and training:
The SAM Reduced Gravity Simulator (RGS) will enable visitors to SAM to experience reduced weight with or without donning a pressure suit. The SAM RGS will enable a user to walk in full 1g, 1/3g for Mars, 1/6g for the Moon, or anything in between. When combined with the pressure suits worn by visiting SAM crews, we anticipate a plethora of research and innovations to come from this advanced facility.
In addition, we will host experiential education programs for school-age students who desire to learn more about human space exploration. The result will be a breathtaking, memorable experience for learners of all ages.
Learn more about the SAM RGS in this recent post … | physics |
https://www.roadweighbridge.com/news/weghing-equipment-and-system-46656.html | 2023-09-30T10:27:30 | s3://commoncrawl/crawl-data/CC-MAIN-2023-40/segments/1695233510671.0/warc/CC-MAIN-20230930082033-20230930112033-00233.warc.gz | 0.922816 | 1,232 | CC-MAIN-2023-40 | webtext-fineweb__CC-MAIN-2023-40__0__324758495 | en | Weighing equipment is usually referred to as a weight weighing instrument for large objects used in industry or trade. It refers to the use of modern electronic technologies such as program control, group control, teleprinting, and screen display, which will make the weighing equipment function. Complete and efficient. Weighing equipment is mainly composed of load-bearing system (such as weighing pan, scale body), force transmission conversion system (such as lever force transmission system, sensor) and indication system (such as dial, electronic display instrument). In today's weighing combined with production and sales, weighing equipment has received great attention, and the demand for weighing equipment is also growing.
Weighing equipment is an electronic weighing device that integrates modern sensor technology, electronic technology and computer technology to meet and solve the "fast, accurate, continuous, automatic" weighing requirements proposed in real life, and effectively eliminate human error. To make it more in line with the application requirements of legal metrology management and industrial production process control. The perfect combination of weighing and production and sales, effectively saving resources of enterprises and merchants, and reducing expenses, has won praise and trust from enterprises and merchants.
Weighing equipment is widely used in industrial, agricultural, commercial, scientific research, medical and health departments, weighing equipment is customarily called scales. The weighing device measures the mass of the object using the force balance principle (Hook's Law). The deformation balance (Hooke's law) determines the mass of the measured object according to the elastic shape variable caused by the weight of the measured object. The shape variable changes with the change of gravity acceleration; the leverage balance is based on the weight of the calibration weight and the weight of the measured object. Balance on the lever to determine the mass of the test object. The balance of the lever is independent of the change in gravitational acceleration, but when the gravitational acceleration is equal to zero, the weighing will fail.
According to the requirements of the symmetrical heavy equipment of each enterprise merchant, the principle structure, function, use, precision and placement position of the symmetrical heavy equipment are also different. Therefore, the difference between the symmetrical heavy equipment is systematically divided.
A. According to the principle structure, the weighing equipment is divided into electronic scale, mechanical scale, electromechanical combined scale
B. According to the function, the weighing equipment is divided into counting scale, pricing scale, weighing scale
C, according to the use of weighing equipment into industrial scales, commercial scales, special scales
D, the weighing equipment is divided into precision
Class I: Special balance Precision ≥1/100,000 Reference weighing equipment
Class II: High-precision balance 1/100,000 ≤ precision <1/100,000 Precision weighing equipment
Class III: Medium precision balance 1/1000 ≤ precision <1/1 million Industrial. Commercial weighing equipment
Class IV: Ordinary scale 1/100≤Precision<1/1000 Thick weighing equipment
Mine-specific track scale
E. According to the installation position, the weighing equipment is divided into a series of weighing equipment such as desktop scales, platform scales, floor scales, loader scales, driving scales, crane scales and track scales.
Structure and composition
The weighing equipment is mainly composed of three parts: the load-bearing system, the force transmission conversion system (ie sensor) and the indication system (display).
Weight bearing system
The shape of the load-bearing system often depends on its use, according to the shape of the weighing object combined with shortening
Loader electronic scale
Designed with features such as heavy time and reduced operational complexity. For example, platform scales and floor scales are generally equipped with flat load-bearing mechanisms; crane scales and driving scales are generally equipped with load-bearing structures; some special specialized weighing equipments are equipped with special load-bearing mechanisms. In addition, the form of the load-bearing mechanism is also the track of the railway scale, the conveyor belt of the belt scale, the body of the loader scale, and the like. The structure of the load-bearing system is different, but the function is consistent.
The force transfer conversion system (ie, the sensor) is the key component that determines the metering performance of the weighing equipment. The common force transfer system lever force transmission system and deformation force transmission system are divided into photoelectric type, hydraulic type and electromagnetic type according to the conversion method. 8, capacitive, magnetic pole deformation, vibration, gyro ceremony, resistance strain type and other 8 categories.
The indicator system of the weighing device is a weighing display, which has two types of digital display and analog scale display. Weighing display type: 1. Electronic scale 1..LCD (liquid crystal display): no plug-in, power saving, with backlight; 2. LED: no plug-in, power consumption, very bright; 3. lamp: plug-in, Power consumption, very high. VFDK/B (button) type: 1. Membrane button: contact type; 2. Mechanical button: combined by many individual buttons;
Electronic hook scale
The lever force transmission system is mainly composed of a load-bearing lever, a force transmission lever, a bracket part and a coupling part such as a knife, a knife bearing, a hook, a lifting ring and the like.
In the deformation force transmission system, the spring is the earliest deformation force transmission mechanism. Spring scales can be weighed from 1 milligram to tens of tons. Springs are available with quartz wire springs, flat springs, coil springs and disc springs. The spring scale is greatly affected by factors such as geographical location and temperature, and the measurement accuracy is low. In order to obtain higher accuracy, various load cells have been developed, such as resistance strain type, capacitive type, pressure magnetic type and vibrating wire type load cell, etc., and the resistance strain type sensor is the most widely used. | physics |
http://www.entronics.co.th/files/products-show.php?product_id=35 | 2021-05-15T07:25:14 | s3://commoncrawl/crawl-data/CC-MAIN-2021-21/segments/1620243991378.48/warc/CC-MAIN-20210515070344-20210515100344-00081.warc.gz | 0.869976 | 126 | CC-MAIN-2021-21 | webtext-fineweb__CC-MAIN-2021-21__0__141819730 | en | EV Series..EV40, EV70, EVH40, EVH81
The EV series AGREE style chambers are available in sizes ranging from 12 to 110 cubic feet (340 L to 3114L), and accommodate electro-dynamic and mechanical vibration systems and/or roll-in product carts. The EV series can be used as a test chamber or as a test chamber with vibration tables.
Humidity option available, Vertical Lift option available, Custom sizes also available
These chambers allow for rapid temperature change rates and all systems are high pressure, leak tested, and operationally tested to performance specifications prior to delivery. | physics |
http://www.cryospace.eu/operation/ | 2018-09-19T15:18:48 | s3://commoncrawl/crawl-data/CC-MAIN-2018-39/segments/1537267156252.31/warc/CC-MAIN-20180919141825-20180919161825-00162.warc.gz | 0.919661 | 321 | CC-MAIN-2018-39 | webtext-fineweb__CC-MAIN-2018-39__0__204901139 | en | CryoSpace is designed to provide immediate cooling for the whole body using the vapour of liquid nitrogen via exposure to cryogenic temperatures.
The operation of the unit is based on the system of liquid nitrogen evaporation and its delivery in the volatile form to the insulated cabin in order to produce and maintain the cryogenic temperatures. The lower part of the cabin includes a ventilation opening through which the remaining nitrogen vapour is removed at the end of each session.
The unit is equipped with an electrically operated lift which automatically sets the users position at a height such that their shoulders are level with the upper edge of unit’s casing. Direct contact between the user and the liquid nitrogen inside the cabin is impossible. The cabin is controlled via a built-in automatic operation system.
A touch screen is positioned on a sidewall of the cabin, which indicates the unit’s parameters and settings and allows control and regulation of the unit. The start-up key and emergency switch are situated under the touch panel.
The length of the session is set individually. It is recommended that the first time session of cryotherapy in CryoSpace last up to 90 (ninety) seconds at the lowest temperature of -140˚C.
Each next treatment can be lengthened by 30 seconds. However the maximum length of a single cryostimulation treatment must not exceed 180 seconds. Typically it is recommended to undergo treatments cyclically once a day: 25 sessions, then 20, 15 and 10 every 6 months. It should only be used by adults of at least 155 cm height. | physics |
https://focusonmath.wordpress.com/tag/data/ | 2018-10-19T08:55:32 | s3://commoncrawl/crawl-data/CC-MAIN-2018-43/segments/1539583512382.62/warc/CC-MAIN-20181019082959-20181019104459-00094.warc.gz | 0.977156 | 634 | CC-MAIN-2018-43 | webtext-fineweb__CC-MAIN-2018-43__0__147830629 | en | I have been thinking about writing about this graphing idea, and with the fall equinox upon us, I wanted to make sure and get this posted! One of the best graphs I ever did in my classroom was one that used data collected over time: namely, we measured the length of the shadow of a metre stick each month, at noon, around the 20th/21st of the month (there would be some slight variations of the date as we needed full sunlight to see the shadow, so if it were cloudy for some days, we measured on the first available sunny day!)
I would ask two students to do the outside measuring. One student would hold the metre stick perpendicular to the ground. Under the tip of the metre stick would be the end of the roll of string. The second student would roll out the string to the length of the shadow, and then cut the string.
They would bring the string inside and measure the length of the string. Additionally they would cut a piece of masking tape (blue or green work best) the length of the string which we used to construct a graph on the ceiling. Across the front of the room, close together, were tags for each month of the school year (September through June for us). For each month we put up the length of masking tape showing the actual length of the metre stick’s shadow for that month and recorded the measured length on the tape.
It was amazing the difference in length of the shadows, especially comparing December and June, the winter and summer solstice months respectively. I live and work in northern British Columbia where we have relatively short winter days (though certainly not as short as in Dawson City, Yukon where I lived for over three years!) Still, even here in Fort St John it was interesting to note the change in the shadow over the months. The first time I did this with a class, I went home that evening excited to tell my husband how long the December shadow was, but he did not believe me! He thought it seemed too long, and he was sure the students had made an error in measuring. He and I had to measure the shadow of a metre stick at home that weekend so he could see its length for himself before he would believe how long it was!
I wish I had taken picture of one of the “shadow graphs” my classes had made on the ceiling of the classroom. It was a powerful representation of the combined effect of the earth’s orbit around the sun along with the tilt of the earth.
I would love to hear about this if you do it with your class. I have a couple of classes in my district that are about to embark on the measuring task in the next few days. I am looking forward to seeing the graphs on the ceilings of those classrooms!
PS: Alternately, one can graph the shadow of a metre stick over the course of a single day, measuring the length of the shadow every hour or every two hours from sun rise to sunset. That is also fascinating data to collect. It might even be interesting to gather both sets of data! | physics |
https://repbi.com/analysis-co-locating-crops-and-photo-voltaic-can-enhance-efficiency/ | 2023-09-29T23:46:18 | s3://commoncrawl/crawl-data/CC-MAIN-2023-40/segments/1695233510529.8/warc/CC-MAIN-20230929222230-20230930012230-00370.warc.gz | 0.901694 | 603 | CC-MAIN-2023-40 | webtext-fineweb__CC-MAIN-2023-40__0__305873735 | en | Rising industrial crops on photo voltaic farms can each enhance industrial meals manufacturing and enhance photo voltaic panel efficiency and longevity, in response to new Cornell College analysis printed within the journal Utilized Power.
Lead writer, Henry Williams, a doctoral pupil at Cornell mentioned: “We now have, for the primary time, a physics-based device to estimate the prices and advantages of co-locating photo voltaic panels and industrial agriculture from the attitude of elevated energy conversion effectivity and solar-panel longevity.”
Senior writer, Max Zhang, professor on the Sibley College of Mechanical and Aerospace Engineering added:
“There’s potential for agrivoltaic techniques – the place agriculture and photo voltaic panels co-exist – to supply elevated passive cooling by taller panel heights, extra reflective floor cowl and better evapotranspiration charges in comparison with conventional photo voltaic farms.
“We are able to generate renewable electrical energy and preserve farmland by agrivoltaic techniques.”
Crops on photo voltaic farms
The research references New York for example the place about 40% of utility-scale photo voltaic farm capability has been developed on agricultural lands, whereas about 84% of land deemed appropriate for utility-scale photo voltaic improvement is agricultural, in response to a earlier analysis research from Zhang’s group.
The engineers confirmed that photo voltaic panels mounted over vegetation have decrease floor temperatures in comparison with these arrays constructed over naked floor.
Photo voltaic panels had been mounted 4m above a soya bean crop and the photo voltaic modules confirmed temperature reductions by as much as 10°, in contrast with photo voltaic panels mounted a 0.5m above naked soil.
The cooling impact is extra important than that induced by better panel top, and the passive cooling provides to photo voltaic panel effectivity, in response to the paper.
The analysis indicated that the temperature drops result in an improved photo voltaic panel lifespan – and improved, long-term financial potential.
“As you lower the photo voltaic panel working temperature, you’ll be able to enhance effectivity and enhance the longevity of your photo voltaic modules,” Williams continued.
“We’re exhibiting twin advantages. On one hand, you’ve meals manufacturing for farmers, and then again, we’ve proven improved longevity and improved conversion effectivity for photo voltaic builders.”
The authors state that understanding this mutually useful idea comes at a vital time for agricultural manufacturing, as world meals calls for are anticipated to extend by 50% by 2050, to feed an anticipated 10 billion folks, in response to the World Assets Institute.
On the identical time, it’s crucial to speed up the deployment of renewable vitality to mitigate the influence of local weather change, the college researchers indicated. | physics |
http://drying-ovens.com/1-1-3-sgdp-industrial-hot-air-oven.html | 2022-05-24T02:33:26 | s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662562410.53/warc/CC-MAIN-20220524014636-20220524044636-00175.warc.gz | 0.688953 | 489 | CC-MAIN-2022-21 | webtext-fineweb__CC-MAIN-2022-21__0__225189594 | en | SGDP is our most universal drying oven with a maximum temperature of 350 ℃. Equipped with a PID temperature controller with LED display, time and temperature is easy to monitor and adjust.
The air passage can be designed based on customer needs, such as horizontal airflow (front to back), vertical airflow or horizontal airflow (side to side). The forced air circulation system helps unify the temperature so that this oven is suitable for OLED flexible printed circuit, printed circuit board, capacitor and transformer after dip coating. If anti-oxidation is required, an inert gas inlet port is available to refill nitrogen.
The standard configurations are fan, heating element and controller, but the panel,working chamber and doors can be customized according to demands. The layer amount and shape of chamber, the material of panel and surface coat are free to choose.
|Model||Temperature Range（℃）||Temperature Fluctuation (℃)||Temperature Uniformity（℃）||Heating Power (kW)||Voltage（V）||Internal Dimensions H×W×D（mm）||External Dimensions H×W×D（mm）| | physics |
https://www.essexny.us/events/lyceum-navigating-the-autumn-skies-other-astronomical-musings/ | 2022-05-17T23:15:33 | s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662520936.24/warc/CC-MAIN-20220517225809-20220518015809-00440.warc.gz | 0.905583 | 438 | CC-MAIN-2022-21 | webtext-fineweb__CC-MAIN-2022-21__0__6923875 | en | The Essex Calendar is the quickest and easiest way to discover what’s happening in and around Essex, NY. In addition to the calendar view, you can view a list of upcoming events and add an event. (Lost your password?)
NOTICE In light of the COVID-19 many events in the country and our community are being canceled or postponed. We will do our best to update events, but we recommend you double-check with the venue/event organizer to confirm scheduled events are taking place before attending.
- This event has passed.
LYCEUM: NAVIGATING THE AUTUMN SKIES & OTHER ASTRONOMICAL MUSINGS
September 28, 2021 @ 7:00 pm – 8:00 pm
The Grange Fall Lyceum lecture series: NAVIGATION
How do we find our way in the world? This series will explore some aspects of human and animal navigation, from recognizing landmarks in the night sky to cartography, vertical route-finding, and the long-distance migrations of birds and fish.
Navigating the Adirondack Autumn Skies and Other Astronomical Musings
In this two-part talk, Lisabeth Kissner will first give some historical perspective on astronomy and space science, and then demonstrate how to visualize the space around us, observe the sky, and distinguish common celestial phenomena. A special digital program will help us “see” the night sky in the Adirondacks.
Lisabeth Kissner is the director of the Northcountry Planetarium as well as a lecturer of astronomy and the faculty advisor for the Galilean Society Astronomy Club at SUNY Plattsburgh. Lisabeth has been appointed a Solar System Ambassador, by the Jet Propulsion Laboratory of the National Aeronautics and Space Administration. The ambassadors program is designed to act as an interface between the space exploration community and school students as well as the general public at large. As an ambassador, Lisabeth coordinates and conducts events or programs which feature either information on NASA’s space exploration missions, celestial phenomena or dark sky awareness.
Suggested donation: $5 per lecture / students free. | physics |
http://www.guzhu15.site/en/internet-of-things-applications/ | 2021-01-15T14:04:57 | s3://commoncrawl/crawl-data/CC-MAIN-2021-04/segments/1610703495901.0/warc/CC-MAIN-20210115134101-20210115164101-00165.warc.gz | 0.855745 | 245 | CC-MAIN-2021-04 | webtext-fineweb__CC-MAIN-2021-04__0__73926051 | en | Self-powered IoT Applications
EnOcean’s energy harvesting wireless sensor technology collects energy out of air. The energy existing in our environment, for example kinetic motion, pressure, light, differences in temperature, is converted into energy for wireless communication. Combining miniaturized energy harvesters and ultra-low power wireless technology creates maintenance-free sensor solutions for use in buildings, smart home and industrial applications as well as for the Internet of Things.
Self-powered wireless switches, sensors and controls cut installation cost and time, and enable efficient use of energy.
EnOcean makes a smart home smarter by increasing comfort and security.
Wireless LED Control
The Wireless LED controls standard with energy harvesting wireless switches & sensors, controllers and tools.
Outdoor environmental monitoring
Self-powered wireless long-range sensor system for outdoor environmental monitoring for the Japanese market.
Energy harvesting wireless sensor nodes for industrial applications.
EnOcean - for a wireless and self-powered Internet of Things
Partnerships for the IoT
The EnOcean Alliance partners with AllSeen Alliance, Open Interconnect Consortium, EEBus Iniative and OSGi Alliance to realize seamless, standard-crossing communication in the IoT. | physics |
http://bukaymedia.com/videos/PtRich/Spider/spider.htm | 2021-05-10T19:01:29 | s3://commoncrawl/crawl-data/CC-MAIN-2021-21/segments/1620243991759.1/warc/CC-MAIN-20210510174005-20210510204005-00179.warc.gz | 0.954603 | 652 | CC-MAIN-2021-21 | webtext-fineweb__CC-MAIN-2021-21__0__10464706 | en | Spiders are incredible engineers. This is a slow motion and normal speed close-up movie of a common garden spider building a web. I thought the web-building process was amazing before I grabbed my camera--but even more so after I slowed down the footage to 10% of normal speed! So fast and efficient is this spider as it extracts silk from its abdomen, shifts its grip on the silk fibers from claw to claw, measures distances, and creates just the right amount of tension to keep the web taut. And the third leg from the front on the spider's left side appears to be missing it's foot! Of great interest to me was how the spider attached the silk fiber at each junction.
After a little research on "How Things Work" at http://tinyurl.com/3vewxjk I learned that spiders make both sticky and non-sticky silk fibers when constructing a web. The non-sticky silk fibers are the radial fibers going from the center of the web to the outside edges. The sticky "cross beam" fibers are the ones that are being constructed in this film. At each silk junction a new sticky silk fiber is attached to a supporting non-sticky fiber. While watching how the spider adeptly manipulated the web, its position, tension on the silk, extraction of the silk from its abdomen, and the attachment of the thread at each junction, I was filled with wonder! So, I decided to slow the motion to 10% of normal speed so I could better see the details.
At first I thought the spider tied some sort of a knot at each junction. However, when I watch in slow motion, this does not appear to be the case. The spider uses a claw to grab the target non-sticky fiber, and appears to attach the sticky fiber to a location below the claw. I suspect that the spider's leg has another claw or spike (hidden from view) that it uses to line up the thread and hold it in place at the junction point while it pulls the abdomen away to extract the next thread of silk. What really amazes me is how well the silk threads stick together! It looks like they are being held together by a natural form of contact cement! If any spider experts watching this better understand how the silk junction bond is formed, please leave a explanatory comment.
In case you are wondering what the white stuff that the spider is chewing on at the end, it is pieces of silk that it cleaned up from the old web that it is recycling.
Here are some technical details about this shoot: The spider is about 1" long and my lens distance varied from about 6-12' from the spider. I used a Panasonic GH2 with the stock 14 - 140 mm lens and recorded the footage at 1080i and edited it at 720p30.
Meanwhile, I also discovered that scientists have successfully implanted silk making genes from spiders into goats and are harvesting the silk from the goat's milk! The high tensile strength of spider silk combined with its flexibility and stretch ability appear to have great potential for use in many fields including medicine.
For more on this go to http://tinyurl.com/2eew8n5. | physics |
http://www.flybackenergy.com/about-us/ | 2018-08-15T04:51:22 | s3://commoncrawl/crawl-data/CC-MAIN-2018-34/segments/1534221209884.38/warc/CC-MAIN-20180815043905-20180815063905-00623.warc.gz | 0.908657 | 150 | CC-MAIN-2018-34 | webtext-fineweb__CC-MAIN-2018-34__0__104303752 | en | Having spent many years designing and installing power systems for the telecom industry, the founders had continually battled the detrimental effects of the flyback energy inherent in all inductive circuits. Understanding the opportunities for improved efficiencies, they set to work to resolve this pervasive and seemingly unsolvable problem. After performing hundreds of experiments, they developed and patented a breakthrough technology that dramatically improves the conversion, control and conservation of electricity in inductive electrical circuits and equipment.
Applying that control discovery to motors, inductors, transformers, and power conversion equipment provides significant energy savings, and is the patented foundation for FlyBack Energy.
Or, for more information or to discuss how MER® technology can help you drive down your capital costs and operating expenses: Contact Us | physics |
https://wvhtf.org/power-converters-for-microgrids-and-distributed-energy/ | 2020-03-31T02:43:07 | s3://commoncrawl/crawl-data/CC-MAIN-2020-16/segments/1585370499280.44/warc/CC-MAIN-20200331003537-20200331033537-00539.warc.gz | 0.916749 | 174 | CC-MAIN-2020-16 | webtext-fineweb__CC-MAIN-2020-16__0__141024929 | en | The High Technology Foundation’s Power Electronics and Electromagnetics team is developing AC/DC, DC/DC, and DC/AC power converters for microgrids and distributed energy applications. A ruggedized DC/DC converter capable of 60 kilowatt operation in moderate-sized microgrids has been built. The unit is hermetically-sealed and capable of operation in harsh environments under extreme ambient conditions. The unit is designed to allow power combining of multiple units on a single transmission line. To couple AC generators to the DC/DC converter, a 60 kilowatt 3-phase AC to DC converter has been designed in detail. The AC/DC converter is power-factor-corrected so that optimal source loading is assured. The unit is designed for two-way power flow to accommodate regenerative loads such as electric motors. | physics |
https://cambridge-energy.co/why-solar-tracking/ | 2024-04-19T08:48:32 | s3://commoncrawl/crawl-data/CC-MAIN-2024-18/segments/1712296817382.50/warc/CC-MAIN-20240419074959-20240419104959-00401.warc.gz | 0.926963 | 343 | CC-MAIN-2024-18 | webtext-fineweb__CC-MAIN-2024-18__0__17558379 | en | Solar tracking is a racking technology that rotates modules to follow the sun through the day, using motors controlled by electronics. By following the sun the solar modules are exposed to more direct sunlight during the day and thus generate more energy.
The main solar tracking technologies are single-axis (following the sun from east to west) and dual-axis tracking (following the sun from east to west and north to south).
Generating electricity using solar PV requires an upfront capital investment. The rate at which this investment is paid off is a function of the operational life of the solar plant, and its energy yield i.e. how efficiently it can convert sunlight into electricity.
The yield of a solar plant is increased by up to 35% when using a combination of tracking and bifacial modules versus using fixed tilt. Single-axis solar trackers with bifacial solar modules are the dominant technology in modern utility-scale solar projects, due to their favourable economics.
The longer a solar plant is operational the better the potential returns. Most solar plants are designed to last 25-30 years and their financial returns are calculated on this basis.
The most common metric to compare the financial returns of solar plants is the Levelized Cost of Energy (LCOE). A lower LCOE normally means a more favourable return on investment, however in cases where high cost electricity is being displaced by solar the return on investment (ROI) is a more realistic metric to consider. Due to the increased energy yield, solar tracking offers a much lower LCOE and higher ROI compared to fixed tilt.
Discover how we have simplified the business of solar with robust, prefabricated solutions here. | physics |
https://inspectitall.blogspot.com/2017/07/why-does-condensation-form-on-outside.html | 2019-01-16T11:05:30 | s3://commoncrawl/crawl-data/CC-MAIN-2019-04/segments/1547583657151.48/warc/CC-MAIN-20190116093643-20190116115643-00259.warc.gz | 0.926341 | 421 | CC-MAIN-2019-04 | webtext-fineweb__CC-MAIN-2019-04__0__10882070 | en | Because cold air can hold less moisture than warm air, as the temperature falls the relative humidity rises and, when the temperature of a surface falls enough, it reaches the dew point—which is 100% relative humidity—and condensation forms. The window glass of an air conditioned home will be cooler than the outdoor air on a warm morning and reaches the dew point temperature before other outdoor surfaces.
Occasionally, we get asked the question “Why do I have condensation when my windows are insulated?” An insulated window still has some heat/cold transmission, and the exterior glass surface will still be slightly cooler because of the chilled indoor air.
Trying to determine why one window has condensate on it and a nearby one does not can get complicated due the variables at the different locations. Here’s few things that can affect the formation of condensation:
- The direction the window is facing.
- The level of shade from an overhang or tree.
- Minor leakage of the gas between the panes of an insulated window will deteriorate its performance and allow the outside surface to be slight cooler than an adjacent window with no leakage.
- Moisture is constantly rising out of the ground and, if a window is over damp soil, the higher humidity above the soil may cause condensation sooner than a window on a screen porch on the same wall.
- The indoor temperature of one room of the house may be slightly cooler than another room and decrease the temperature of the glass.
- Any combination of these variables.
If you suspect that the condensation is due to the loss of the inert gas between the panes of an insulated window, eventually the problem will show itself as a cloudiness on the glass. It forms on the surfaces of the panes of glass that face the inert gas space, so the haze cannot not be cleaned away.
If you want your windows inspected then call us! We are home inspection experts! We can inspect your windows and give you a report on the condition and advise on replacement or repair. | physics |
http://rameznaam.com/2011/06/09/solar-cheaper-than-coal-in-3-5-years-ge-and-first-solar-think-so/ | 2018-01-19T05:22:08 | s3://commoncrawl/crawl-data/CC-MAIN-2018-05/segments/1516084887746.35/warc/CC-MAIN-20180119045937-20180119065937-00353.warc.gz | 0.937581 | 324 | CC-MAIN-2018-05 | webtext-fineweb__CC-MAIN-2018-05__0__95086276 | en | The news is carrying two stories in the last two weeks pitching solar as potentially cheaper than current electrical rates in the next 3-5 years.
First, in an interview with Bloomberg, GE’s global research director Mark M. Little said that their thin film solar PV (now at 12.8% efficiency) could be cheaper than fossil fuel and nuclear electricity in 3-5 years.
Then, yesterday, First Solar said that they believed they’d be selling solar power to CA utilities at 10-12 cents per kilowatt hour in 2014.
Both of those are well ahead of the Moore’s-Law-like exponential price decrease of solar that I’ve blogged about previously.
Could they be for real? Possibly. If they can keep installation costs and operating costs low enough, solar cells that are in pre-production are already at the $1 / watt manufacturing price threshold that would allow cheaper-than-fossil-fuel solar energy.
When solar is truly cheaper than fossil-fuel derived electricity, we’ll hit a new tipping point in energy. We’ll still need some coal, natural gas, or nuclear power for night time and cloudy days, but those power usage levels are lower than the peaks on sunny afternoons in summertime. With cheap solar PV, most of the new capacity built will make more sense as solar than anything else.
And eventually, cheap solar electricity will allow us to capture CO2 from the atmosphere and turn it into liquid fuels for storage and for transportation. (More on that another day.) | physics |
https://adetoladaniel.wordpress.com/2020/07/03/the-snare-%C2%B2/ | 2023-05-28T03:16:01 | s3://commoncrawl/crawl-data/CC-MAIN-2023-23/segments/1685224643462.13/warc/CC-MAIN-20230528015553-20230528045553-00599.warc.gz | 0.931207 | 1,419 | CC-MAIN-2023-23 | webtext-fineweb__CC-MAIN-2023-23__0__137402181 | en | On many snare drums, a “venting hole” is made “to ease the motion of the heads” avoiding too high pressure rise inside the shell. While it is a common practice to drill one or many holes in the shells, some manufacturers prefer none, and some other are rally imaginative when it comes to “venting the drum”.
The studies on Timpani, showed that strong coupling occurred between the membrane normal modes and the cavity (closed in the case of a timpani bowl). That coupling explained how a non-harmonic system (the normal modes of a membrane) became nearly harmonically tuned (with a distinctive pitch) sometimes up to the 5th partial as some modes would change frequency depending on their mode shape.
Back to snare drum, that venting hole is defined as a sign of some “zero hertz” coupling: static pressure inside the shell linked to membrane deformation (and we will see that we mostly speak of the (0,1) mode being not volume conservative) causes flow out of the drum. But how does this work at higher frequencies? and how a axisymmetric venting opening would better accommodate the axissymetry of the instrument rather than a single hole ? What about using this opening as a radiating element and maximizing its efficiency through a “ported” profile ?
Lab tests :
Those questions have led Repercussion to develop a number of prototypes, and take them to the lab after positive subjective appraisal coming from professional percussionists. The snares studied are of widely different construction from the personal collection of Repercussion:
- 13×7 Stave Oak : is a 13” diameter, 7” deep drum, and has a shell built by stave technique : alike barrels, pieces of wood are beveled and assembled together then lathed to perfect roundness. This is said to minimize the amount of glue vs ply shells and therefore, the damping of the shell and the sustain of the sound.
- 14×6,5” “Free Floating” : is a 14” Diameter,6,5” deep drum with a rolled sheet metal steel shell (thickness = 1mm). The particularity of this drum is to feature no tensioning devices (lugs) or strainer on the shell itself, hence letting the shell “free to resonate” as claimed by the manufacturer.
- 14×6,5” Mahogany : is a 14” diameter, 6,5” deep drum, with a shell made out of mahogany plies. 4 layers of mahogany are glued together, and reinforcement rings at the top and bottom of the shell guarantee roundness and strength.
- Repercussion Orchestral snare : is a 14” diameter, 6,5” deep prototype drum, with a 15 ply maple shell (11mm thickness). Its main feature is a radial ported vent in its center resulting in a “split shell” architecture (2 half shells).
- Repercussion 1O slots vent : is a 14 “ diameter, 6,5” deep prototype drum with a 8 ply (6mm) maple shell, featuring ported vent close to the top head, between each lug.
- Repercussion Standard Snare radial vented : is a 14” diameter, 6,5” deep drum with a radial ported vent, made from a 8 ply (6mm) maple shell.
A “gravity operated” arm has been developed to provide exactly the same kinetic energy to a drumstick, while controlling the trajectory to avoid multiple strokes. Vibration and acoustic measurement have been performed in anaechoic room, using lab grade equipment.
A very distinctive element of a snare drum is the snare itself. This is a somewhat tricky element seen from the NVH engineer, as it is basically closer to one infamous “squeak and rattle” source. It is stretched across a membrane and would therefore rub and clatter against that membrane, depending on the adjustment of the membrane and the snare itself…In a nutshell : a very nonlinear element. The measurements below have been made with snares “on” and “off” to understand their contribution to the sound.
With a first membrane mode (0,1) located in the 200Hz third octave band for all the drums, it is noticeable that the snare Adds quite a lot of energy in the 1kz-1kHz band, and on “standard vented” (holes) drums, tend to “chop off” the first membrane modes up to 500 Hz by 10-12 dB.
Same as above, but seen up to 1kHz, with a narrowband spectrum.Note the presence of a lower component in the 120 Hz range on Repercussion snares, that will be discussed in another page.
On repercussion snares, the fundamental motion (1,0);(1,1);(2,1) modes and first partials are kept intact from the snare action, on all other standard drums those components of the sound are chopped off.
This is due to the loss of energy in the friction of the snares against the batter (resonant) head bringing some heavy damping to the top head : the smaller the venting, the strongest the coupling between the two heads, and the stronger the damping of the top head first modes. The snare is bringing heavy damping to the top head if the venting is not decoupling them enough.
So Repercussion vented drums keep the low end, all right, what about the high end of the spectrum ?
On the left: the loss in the fundamental third octave band : 11 to 12 dB loss for standard drums, 2 to 5 dB maximum loss for Repercussion.
On the right, global gain in the high frequency range (1kHz – 10kHz) ranging from +24 to + 32 dB
On Repercussion “Bessel vented drums” the sound is perceived with greater presence by the player, and quite notably by the audience a few meters away – One might think, in the constant “WYSIWIG” mindset it is because of the larger opened surface of the vent, drawing more sound around the drum. Although it is true that a ported vent radiates way more efficiently than a standard hole, for the particular motions of the head at low frequency responsible for that feeling of “presence”, it is really that freedom from the damping mechanism of the snares that helps build this “in your stomach” sound perception. | physics |
http://www.msi-sensing.com/broadband_dielectrics.htm | 2023-03-21T20:12:27 | s3://commoncrawl/crawl-data/CC-MAIN-2023-14/segments/1679296943746.73/warc/CC-MAIN-20230321193811-20230321223811-00281.warc.gz | 0.852422 | 5,799 | CC-MAIN-2023-14 | webtext-fineweb__CC-MAIN-2023-14__0__152587846 | en | Free- and bound-water rotation in aqueous systems
Molecular rotation in polar liquids
Grain-boundary charging in porous materials
Ion conduction and double-layer electrode charging in liquid systems
Large molecule reorientation in polymer materials
We provide in-depth analysis and
interpretation as requested. We provide data in common dielectric
formats including complex permittivity as a function of frequency,
complex impedance diagrams, and Cole-Cole plots. We model data using
standard Debye, Cole-Cole, and Cole-Davidson models, to extract
molecular-level information on parameters such as relaxation time,
relaxation amplitude, and distribution of relaxation times. From
this we provide information on the state of processing of the material,
for such properties as viscosity, percent reaction, chemical state
of binding, etc.
MSI performs Broadband Dielectric Spectroscopy over the frequency
range 10 Hz to over 10 GHz. We use Low Frequency Impedance methods below 10 MHz and a combination
of TDR Dielectric and Microwave Cavity methods above 10 MHz. In aqueous materials we extend reliably
to the multi-GHz range to capture free-water behavior, using our TDR Smith-chart analysis.
Each of these areas is discussed below.
High-Frequency TDR Dielectric Spectroscopy
Multi-GHz TDR Smith-chart methods
TDR Dielectric Spectroscopy
Low-Frequency Dielectric Spectroscopy
Appendix - Smith chart basics
1. High-Frequency TDR Dielectric Spectroscopy
MSI uses Time Domain Reflectometry (TDR) Dielectric Spectroscopy for
high-frequency materials analysis, an innovative approach to high
frequency dielectric spectroscopy. The sensing electrodes are interrogated not with a continuous frequency
wave, but with a rapid voltage pulse containing a broad range of
frequencies at once [1-3]. The reflected pulse is converted to
complex permittivity by Laplace (Fourier) Transform, separating the
sensor response from connecting-line artifacts by propagation delay. An advantage is results can be interpreted in either
frequency or time domain, using calibration and frequency domain
analysis for high-quality scientific work, or direct analysis of the
reflected transient for robust field-grade monitoring.
TDR Dielectric Spectroscopy is related to conventional
Time-Domain-Reflectometry used in closed-circuit fault testing
[4-5]. However, TDR Spectroscopy focuses on a time and frequency
analysis from a lumped capacitance sensor while conventional TDR
focuses on spatial differences along a distributed transmission
TDR Background The expressions governing
TDR Dielectric Spectroscopy are described
in the literature [1,6]. An incident voltage pulse vi(t) propagating along
a transmission line of characteristic admittance Gc
encounters a terminating capacitive sensor of admittance Y producing
a reflected pulse vr(t). The terminating admittance Y is
related to the total current-to-voltage ratio Gc
(vi - vr)/(vi + vr),
where vi and vr are the Laplace transforms
of the incident and reflected pulses. The terminating admittance is
then related to sample
permittivity by Y=iωεCo so the permittivity is:
To establish a common time reference, the incident voltage is
substituted by the empty sensor reflection, by writing Equation 1
for both empty sensor and sample reflections and manipulating to
eliminate vi. The result is a reflection function
of similar form:
where vr,r and vr,x are the Laplace transforms for the
empty sensor and sample reflections. From this a differential expression can be written for
complex permittivity, or alternatively a bilinear form:
Where A, B, and C are complex parameters determined by calibration
with known reference standards. Additional methods such as nonuniform sampling and timing
control are described in the literature.
A typical TDR spectrum obtained in our laboratory for ethanol is
shown below. On the left is real permittivity and on the right is
the imaginary permittivity, both shown over a frequency range 100
MHz to near10 GHz. The data shows the expected dipolar relaxation
around 1 GHz, which continues to trail off in permittivity and loss
to around 10 GHz. A theoretical model based on Debye theory of
viscous rotation [7,8] is overlaid on both real and imaginary
components for comparison
The relaxation spectrum shifts with typical variations in material
parameters such as temperature, viscosity, molecular weight, mixture
concentration, etc. For example, the data below shows the
ethanol relaxation varying with temperature, with the loss peak
increasing to around 2 GHz at 55°C. Similar changes are seen
with other material variations such as addition of water or
substitution of different molecular-weight alcohols.
The data can also be presented in Cole-Cole or complex impedance
format, to further aid in the analysis . For example, the data
below shows a complex impedance arc in cement paste immediately
after mixing, at higher frequencies and shorter cure times than
allowed by low-frequency measurement. An arc in the complex
impedance plane demonstrates that material behaves as an electrolyte
resistance in parallel with an interelectrode capacitance, allowing
the bulk resistance to be quantified independent of electrochemical
effects at the electrodes.
2. Multi-GHz TDR Smith-chart methods
MSI extends measurement bandwidth to multi-GHz frequencies reliably
using inexpensive single-use sensors. The importance is capturing
the free-water relaxation occurring in aqueous systems, and
separating it from bound-water relaxation and other effects
occurring at lower frequencies. The ability to capture free water
response reliably opens a range of new applications, from industrial
process monitoring, to biotech, and other areas.
Despite its relative low cost and simplicity, TDR is an RF/microwave
measurement requiring RF/microwave levels of analysis. MSI recently
developed a TDR Smith Chart , in which the Laplace transform of
the sample reflection is divided by the Laplace transform of the
empty-sensor reflection and displayed in the complex plane, similar
to Vector Network Analyzer (VNA) methods.
The magnitude of this ratio is always one, for low-loss
materials, so the display traces a circle over the range of
frequencies, with the variation in phase appearing as a variation in
real and imaginary components. Deviations from this circle reveal
unwanted signal artifacts, isolating these
artifacts from normal signal response up to 10 GHz and above.
Transmission losses cancel, so movement across additional
Smith-chart circles of constant susceptance and conductance indicate
actual sensor response. The TDR Smith chart provides a quick
diagnostic, prior to time-consuming calibration, showing whether
transient data is artifact-free and following expected behavior, or
whether corrective steps must be taken.
Smith chart examples
Representative TDR Smith charts are shown below. Each shows the
ratio of sample-material Laplace transform to empty-sensor transform, or relative reflection coefficient
to 15 GHz. Each shows the signal tracing a semicircular arc around
the lower half of the complex plane, showing a reflection
coefficient with near constant magnitude
and increasing phase shift.
Frequency labels are shown at select points, starting at 2
GHz on the right and continuing to 15 GHz on the left.
An admittance Smith chart is used, with constant susceptance
and conductance circles originating from the left, treating the
sensor and sample material as a parallel circuit model. Both
susceptance and conductance are normalized to the characteristic
0.02 S/m line admittance in the usual manner, and labeled on the
An example for non-conducting liquids is shown on the left for
dichloromethane (ε' = 8.85), acetonitrile (ε' = 37.5),
and 0.7 M water/ethanol (10 < ε' < 45, measured with standard 3.5 mm
semi-rigid coax with a flat termination. The low-permittivity dichloromethane
traces a short arc around the lower right of the complex plane,
crossing circles of constant susceptance
(iωεCo/.02)slowly with frequency.
The high-permittivity acetonitrile traces a longer path around the lower half of
the complex plane, crossing circles of constant susceptance more rapidly
with frequency. The moderate-permittivity ethanol traces an intermediate path around the
complex plane, crossing circles of constant susceptance, but also
moving to the interior and crossing circles of constant conductance.
This results from the high ethanol loss, which causes the
signal to spiral inward with increasing frequency, crossing circles of
constant susceptance and constant conductance .
An example for conducting liquids is shown on the right for water
and salline solutions (ε’ ≈ 78). The
deionized water traces an arc around the perimeter of the complex
plane in the usual manner, while the saline shifts the arc to the
interior with increasing concentration, following circles of
Smith chart diagnostics
The TDR Smith chart reveals acquisition and analysis errors by
displaying results on a normalized unit circle in the complex plane, accentuating
small anomalies between real and imaginary components. Since the reflection coefficient is
a precursor to the reflection function used in bilinear
calibration, the TDR Smith chart is a valuable tool in detecting
errors upstream, before time-consuming calibration is performed.
One example is an
incorrect setting in baseline or integration cursors used in
the numerical Laplace integration. Below on the left is a TDR Smith
chart for acetonitrile and the 0.7 M water/acetone solution, in
which a 5 mv offset is introduced in the vertical baseline, about 1%
of the full 400 mv reflection. An
obvious artifact appears in the transformed display around 10 GHz,
with some distortion leading up to this frequency. Similar artifacts
occur for other types of acquisition and analysis errors, including
improper Laplace truncation, multiple reflections within input
lines, timing errors, and sensor damage. Each error propagates further into the calibration process,
appearing in the reflection function ρ(ω), the bilinear calibration
parameters A(ω) and B(ω), and the final calibrated permittivity
Another example is an internal reflection from sample boundaries. Below on the
right is a TDR Smith chart for a sensor with a 1 mm protruding pin
in a small beaker of water (ε’ = 78). When positioned near the
center of the beaker the red trace appears, when positioned near one
side the blue trace appears. An obvious difference is a small loop
appearing around 1 GHz, apparently representing a radiated signal
reflecting from sample boundaries. The reflection occurs because of
the high dielectric discontinuity between the water and surrounding
air, but is too small to be seen in the direct transient.
It is accentuated by the differential and bilinear methods
used in calibration, but is seen at an early stage in the TDR Smith
A third example is the approach to
which varies with pin length and sample permittivity.
Below on the left is a TDR Smith chart for 2 sensors in
water, one ground perfectly flat and the other with a 0.3 mm
protruding pin. A serrated shield surrounds the pin to prevent
radiation and sample boundary reflections. For the flat sensor the
signal traces a path around the lower half of the complex plane in
the usual manner, to around 10 GHz.
For the 0.4 mm pin the signal traces a more rapid path around
the complex plane, but begins to distort at around 7-8 GHz. The
distortion apparently represents the approach to pin resonance, and
occurs at this position on the Smith chart because the reflection
coefficient is defined as the ratio of the sample reflection to the
empty-sensor reflection, rather than the incident pulse. This is
done to eliminate timing differences between incident and reflected
pulses, but results in the TDR reflection coefficient being a relative
reflection coefficient between sample and empty-sensor reflections:
Which can be adjusted to an absolute reflection coefficient Гa by
multiplying by the term
which corrects the small difference between incident pulse and
empty-sensor reflection. The absolute reflection coefficient is shown on the right,
where the signal for the 0.4 mm pin crosses the negative real axis
into the inductive region at around 7-8 GHz. Obviously this
situation must be avoided, by adjusting the pin length and/or sample
3. Multi-GHz TDR Dielectric Spectroscopy
An example of multi-GHz TDR Dielectric Spectroscopy is the
monitoring of cement hydration by following the free- and
bound-water relaxation spectrums at frequencies of 10 GHz and above.
An inexpensive capacitance sensor is made by terminating a
standard 3.5 mm semi-rigid coaxial line perfectly flat, and
immersing in fresh cement paste. The flat termination provides
approximately 20 femtofarads (ff) fringing capacitance, providing an
appropriate load admittance into a medium-permittivity material over
the range 100 MHz to 15 GHz.
A first step is the selection of calibration
liquids with similar permittivity/loss spectra. Any RF/microwave
measurement, be it VNA and TDR, relies on calibration with known
reference standards to remove artifacts originating in the
instrument and connecting lines. VNA requires 3 calibrations
generally open, short, and 50
ohms. TDR also requires 3 calibrations, where for materials
measurements we use the empty sensor and 2 known reference liquids,
whose permittivity and loss closely approximate the unknown
material. Since the
permittivity and loss of cement decrease during cure, as water is
consumed in reaction, we choose 2 reference liquids which
approximate the permittivity/loss at early cure and late cure,
assuming that the signal evolution during cure lies in between.
A good calibration for early cure is a mixture of saline and PMMA
microbeads. The saline provides the strong free-water relaxation
expected in fresh cement past, while the PMMA reduces the transition
amplitude from 78 to around 40. The saline also adds a strong ion
conductivity, similar to cement paste. A good calibration for late
cure is a low-permittivity solvent with a high relaxation frequency,
such as dichloromethane or THF. The high relaxation frequency
provides the slowly decreasing permittivity and rising loss expected
at late cure, typical of porous solids. A trace amount of zinc
nitrate adds a small conductivity at long transient times, keeping
the transient resolvable at long times and allowing calibration
parameters to be calculated over the entire range.
A second step is examination of the
TDR Smith charts at the two calibration limits, to correct any errors in sensor
response or acquisition and analysis. Smith charts for PMMA/saline
and THF/zinc nitrate are shown below, overlaid with cement cure data
at 0 and 72 hours, respectively. For the early calibration, the relative reflection
coefficient traces a rapid path to 15 GHz but does not cross
resonance; for the late calibration the reflection coefficient
traces a more gradual path due to the lower permittivity and
susceptance. In both cases the signal is smooth to 15 GHz, with no
sample boundary reflections, acquisition/analysis errors, or other
A third step is the calculation of corresponding reflection
functions, which essentially represent the uncalibrated permittivity. Each
reflection function ρ(ω) is calculated from its reflection
coefficient Γ(ω), according to:
Reflection functions for the saline/PMMA and the THF/zinc nitrate
are shown below, with the imaginary parts ρ’’ multiplied by εoω
to display the uncalibrated dielectric conductivity.
For saline/PMMA, the real permittivity on the left shows a
constant value to near 2-3 GHz and a roll-off around 10 GHz for the
free-water relaxation. The dielectric conductivity on the right
shows a flat region to near 1GHz due to ion conductivity and a rise
around 10 GHz for the free-water loss peak.
For the THF/zinc nitrate, the permittivity and conductivity
are much lower, and an additional feature appears around 1 GHz due
to the zinc-nitrate solute relaxation.
Each reflection function is overlaid with a model function to
generate bilinear calibration parameters. For the saline/PMMA, the relaxation
time is set to 8.2 ps for
water, with the relaxation amplitude adjusted to the lower
saline/PMMA volume ratio. For THF/zinc-nitrate, the relaxation time
is set to 5 ps for THF, to match the slowly falling permittivity and
rising loss over the range.A small solute relaxation is added to the THF/zinc nitrate
model at around 1 GHz. A
constant ion conductivity is added to both calibrations to match the
broad flat region below 100 MHz.
A final step is the generation of bilinear
parameters and the calibration of the cement reflection functions.
Bilinear parameters A and B are found by solving equation (3) for
both reflection functions and their corresponding model functions,
generating 4 simultaneous equations for real and imaginary
components. Details are described in the references . By then
applying parameters A and B to the reflection functions for curing
cement, the calibrated permittivity and conductivity at various cure
times is determined.
Results for hydrating cement paste are shown below, from about 100
MHz to 15 GHz. Separate
free-water relaxation and ion-conductivity regions are clearly seen
in the initial stages of cure. As cure proceeds the free water
permittivity and ion conductivity decrease, and a separate
bound-water region appears in the conductivity around 1 GHz,
representing water attaching to developing microstructure.
4. Low-Frequency Dielectric Spectroscopy
We also provide low-frequency dielectric and impedance spectroscopy
using standard HP4192 Impedance Analyzer methods. Samples are
placed in 4-wire capacitance cell and measured over a frequency
range 10 Hz to 10 MHz. Results can be modeled in the Cole-Cole
permittivity plane or complex impedance plane as appropriate.
An example of low-frequency dielectric spectroscopy is a cured epoxy
thermoset shown below. The epoxy shows polymer-chain relaxation in
the 1 kHz to 1 MHz range, with a broad roll-off in permittivity seen
on the left, and a similarly broad loss peak seen on the right.
Another example is a porous glass sample shown below. The sample
shows strong low-frequency dispersion due to surface currents along
pore edges accompanied by interfacial charging at grain boundaries
(Maxwell-Wagner effect). As the sample is heated to drive off
moisture the low-frequency dispersion disappears, and only reappears
as the sample is returned to ambient for a period of time.
TDR and low-frequency measurement can be combined over an extremely
wide frequency range . The data below shows the real
permittivity of curing cement over a frequency span of 9 decades,
from 10 Hz to 10 GHz. Two relaxations are seen in the figure below,
a low-frequency relaxation due to the mobility of free ions, and
high-frequency relaxation due to the mobility of bound water.
The high-frequency relaxation straddles both TDR and low-frequency
5. Appendix - Smith chart basics
The Smith chart is a convenient way of visualizing the reflection
coefficient on a transmission line, as well as the terminating
sensor impedance, all on one chart. The basic reflection
coefficient is plotted in the complex plane, with additional circles
of resistance and reactance indicating the changing sensor impedance. Smith
charts have been used for many years in VNA work, with numerous
references available in the literature .
For an admittance Smith
chart, used in parallel circuit models,
the starting point is the basic relation between incident and
reflected voltages and currents and the terminating sensor admittance Y(ω).
where the current difference in the numerator is replaced by the
voltage difference multiplied by the characteristic line admittance
(0.02 S/m). Both sides are then divided by the line admittance to
give a relation between the incident and reflected voltages in the
middle and the normalized terminating sensor admittance y(ω) on the left.
where the incident and reflected voltages in the
middle are then written in terms of the
reflection coefficient Γ on the right by dividing through by vi .
Substituting Γ = Γr + iΓi
and y = g + ib
in Equation 9
for the complex reflection coefficient and normalized terminating admittance,
separating real and imaginary parts, and manipulating some algebra, gives 2 equations:
Which are equations of circles
for Γi vs. Γr.
For the first set of circles the radius and offset are determined solely by
the conductance; for the second set the radius and offset are determined
solely by the susceptance. The 2 circle sets thus show
Γi varying with Γr
in a circular manner when either the conductance or susceptance
is held fixed*. Alternatively, plotting both circle sets for
differing values of conductance (red) and susceptance (blue) is equivalent to
adding 2 additional sets of gridlines, showing how the conductance and
susceptance vary as these circles are crossed.
*Γi vs. iΓr
may be varied at fixed conductance or susceptance
by either varying the frequency, as done here, or varying the transmission
line length, as done in antenna load-matching.
6. Technical References
Additional information on broadband TDR Dielectric Spectroscopy can be found at:
R. H. Cole, J. G. Berberian, S. Mashimo, G. Chrssikos, A. Burns,
and E. Tombari, "Time domain reflection methods for dielectric
measurements to 10 GHz", J. Appl. Phys 66, 793 (1989)
H. Fellner-Feldegg, J. Chem Phys. 73, 616 (1969).<.p>
N.E. Hager III, "Broadband Time-Domain-Reflectometry Dielectric
Spectroscopy using variable-time-scale Sampling", Rev. Sci.
Instrum. 65(4), April 1994, p 887. download pdf*
N.E. Hager III, R.C. Domszy, M.R. Tofighi, "Smith-chart
diagnostics for multi-GHz Time Domain Reflectometry Dielectric
Spectroscopy, Rev. Sci. Instrum. 83, 025108 (2012). download
Satoru Mashimo and Toshihiro Umehara, "Structures of water and
primary alcohol studied by microwave dielectric analysis", J.
Chem. Phys. 95 (9), 1 November 1991.
J. Barthel, K. Bachhuber, R. Buchner and H. Hetzenauer.
"Dielectric spectra of some common solvents in the Microwave
Region. Water and Lower Alcohols" Chem. Phys. Letters 165 (4) 19
January 1990 369.
N. E. Hager III and R. C. Domszy, "Monitoring of Cement
Hydration by Broadband TDR Dielectric Spectroscopy", J. Appl.
Phys. 96, 5117-5128 (2004). dowload pdf**
N.E. Hager III, R.C.
Domszy, M.R. Tofighi, “Multi-GHz Monitoring of Cement Hydration
Using Time-Domain-Reflectometry Dielectric Spectroscopy”, Fourth
International Symposium on Soil Water
Capacitance, Impedance and Time Domain Transmission (TDT),
Pointe Claire Quebec, July 2014.
William Hayt, John Buck,
“Engineering Electromagnetics” Eighth Edition, McGraw-Hill, NY,
A. K. Jonscher,
Dielectric Relaxation in Solids, Chelsea Dielectrics Press,
Arthur R. Von Hippel,
Dielectric Materials and Applications, Wiley, New York (1954).
*Copyright 2012 American Institute of Physics. This article may be
downloaded for personal use only. Any other use requires prior
permission of the author and the American Institute of Physics. The
following article appeared in Review of Scientific Instruments and
may be found at http://link.aip.org/link/?RSI/83/025108
**Copyright 2004 American Institute of Physics. This article may be
downloaded for personal use only. Any other use requires prior
permission of the author and the American Institute of Physics. The
following article appeared in Journal of Applied Physics and may be
found at http://link.aip.org/link/?jap/96/5117
Copyright © 2015 Material Sensing & Instrumentation, Inc. | physics |
https://www.laboratoiredubois.ch/en/services/materials-control/coating-thickness-measurements | 2023-12-02T08:57:06 | s3://commoncrawl/crawl-data/CC-MAIN-2023-50/segments/1700679100381.14/warc/CC-MAIN-20231202073445-20231202103445-00057.warc.gz | 0.88833 | 160 | CC-MAIN-2023-50 | webtext-fineweb__CC-MAIN-2023-50__0__58165071 | en | Determining the actual thickness of coatings, surface treatments or diffusion layers requires a careful preparation by cross-section followed by observation and measurement by optical microscopy (as per standard ISO 1463) or electron microscopy (ISO 9220).
We perform thickness measurements of electroplating treatments, thin PVD/CVD layers, lacquers and varnishes, diffusion layers on pieces and items of any type.
This service is often combined with the identification of the nature of the coatings by analysis of their chemical composition. In the case of gold plating, determining the fineness of the gold coating requires a specific procedure.
In some cases, the coating thickness is performed by Scanning Electron Microscopy (SEM) on broken sample (fractography). | physics |
http://www.ledsolarpoweredlights.com/lighting-lumen-efficiency | 2017-04-28T21:47:59 | s3://commoncrawl/crawl-data/CC-MAIN-2017-17/segments/1492917123097.48/warc/CC-MAIN-20170423031203-00598-ip-10-145-167-34.ec2.internal.warc.gz | 0.873853 | 2,051 | CC-MAIN-2017-17 | webtext-fineweb__CC-MAIN-2017-17__0__290912037 | en | Lighting and Lumen Comparison and Conversion
Luminous efficacy is a figure of merit for light sources. It is the ratio of luminous flux (in lumens) to power (usually measured in watts). Depending on context, the power can be either the radiant flux of the source's output, or it can be the total electric power consumed by the source. Which sense of the term is intended must usually be inferred from the context, and is sometimes unclear. The former sense is sometimes called luminous efficacy of radiation (LER), and the latter luminous efficacy of a source (LES).
The LES describes how well the source provides visible light from a given amount of electricity. The LER is a characteristic of a given spectrum that describes how sensitive the human eye is to the mix of wavelengths involved. The luminous efficacy of a source is the LER of its emission spectrum times the conversion efficiency from electrical energy to electromagnetic radiation.
Efficacy and efficiency
In some other systems of units, luminous flux has the same units as radiant flux. The luminous efficacy of radiation is then dimensionless. In this case, it is often instead called the luminous efficiency or luminous coefficient and may be expressed as a percentage. A common choice is to choose units such that the maximum possible efficacy, 683 lm/W, corresponds to an efficiency of 100%. The distinction between efficacy and efficiency is not always carefully maintained in published sources, so it is not uncommon to see "efficiencies" expressed in lumens per watt, or "efficacies" expressed as a percentage.
Luminous efficacy of radiation
Wavelengths of light outside of the visible spectrum are not useful for illumination because they cannot be seen by the human eye. Furthermore, the eye responds more to some wavelengths of light than others, even within the visible spectrum. This response of the eye is represented by the luminosity function. This is a standardized function which represents the response of a "typical" eye under bright conditions (photopic vision). One can also define a similar curve for dim conditions (scotopic vision). When neither is specified, photopic conditions are generally assumed.
Luminous efficacy of radiation measures the fraction of electromagnetic power which is useful for lighting. It is obtained by dividing the luminous flux by the radiant flux. Light with wavelengths outside the visible spectrum reduces LER, because it contributes to the radiant flux while the luminous flux of such light is zero. Wavelengths near the peak of the eye's response contribute more strongly than those near the edges.
In SI, luminous efficacy has units of lumens per watt (lm/W). Photopic luminous efficacy of radiation has a maximum possible value of 683 lm/W, for the case of monochromatic light at a wavelength of 555 nm (green). Scotopic luminous efficacy of radiation reaches a maximum of 1700 lm/W for narrowband light of wavelength 507 nm.
The dimensionless luminous efficiency measures the integrated fraction of the radiant power that contributes to its luminous properties as evaluated by means of the standard luminosity function. The luminous coefficient is
- yλ is the standard luminosity function,
- Jλ is the spectral power distribution of the radiant intensity.
The luminous coefficient is unity for a narrow band of wavelengths at 555 nanometres.
Note that is an inner product between yλ and Jλ and that is the one-norm of Jλ.
|Type||Luminous efficacy of radiation|
|Class M star (Antares, Betelgeuse), 3000 K||30||4%|
|ideal black-body radiator at 4000 K||47.5||7.0%|
|Class G star (Sun, Capella), 5800 K||80||12%|
|ideal black-body radiator at 7000 K||95||14%|
|ideal 5800 K black-body, truncated to 400–700 nm (ideal "white" source)||251||37%|
|ideal monochromatic 555 nm source||683||100%|
Artificial light sources are usually evaluated in terms of luminous efficacy of a source, also sometimes called overall luminous efficacy. This is the ratio between the total luminous flux emitted by a device and the total amount of input power (electrical, etc.) it consumes. It is also sometimes referred to as the wall-plug luminous efficacy or simply wall-plug efficacy. The overall luminous efficacy is a measure of the efficiency of the device with the output adjusted to account for the spectral response curve (the “luminosity function”). When expressed in dimensionless form (for example, as a fraction of the maximum possible luminous efficacy), this value may be called overall luminous efficiency, wall-plug luminous efficiency, or simply the lighting efficiency.
The main difference between the luminous efficacy of radiation and the luminous efficacy of a source is that the latter accounts for input energy that is lost as heat or otherwise exits the source as something other than electromagnetic radiation. Luminous efficacy of radiation is a property of the radiation emitted by a source. Luminous efficacy of a source is a property of the source as a whole.
The following table lists luminous efficacy of a source and efficiency for various light sources:
luminous efficacy (lm/W)
|Incandescent||100–200 W tungsten incandescent (220 V)||13.8–15.2||2.0–2.2%|
|100–200–500 W tungsten glass halogen (220 V)||16.7–17.6–19.8||2.4–2.6–2.9%|
|5–40–100 W tungsten incandescent (120 V)||5–12.6–17.5||0.7–1.8–2.6%|
|2.6 W tungsten glass halogen (5.2 V)||19.2||2.8%|
|tungsten quartz halogen (12–24 V)||24||3.5%|
|photographic and projection lamps||35||5.1%|
|Light-emitting diode||white LED (raw, without power supply)||4.5–150||0.66–22.0%|
|4.1 W LED screw base lamp (120 V)||58.5–82.9||8.6–12.1%|
|6.9 W LED screw base lamp (120 V)||55.1–81.9||8.1–12.0%|
|7 W LED PAR20 (120 V)||28.6||4.2%|
|8.7 W LED screw base lamp (120 V)||69.0–93.1||10.1–13.6%|
|Arc lamp||xenon arc lamp||30–50||4.4–7.3%|
|mercury-xenon arc lamp||50–55||7.3–8.0%|
|Fluorescent||T12 tube with magnetic ballast||60||9%|
|9–32 W compact fluorescent||46–75||8–11.45%|
|T8 tube with electronic ballast||80–100||12–15%|
|Gas discharge||1400 W sulfur lamp||100||15%|
|metal halide lamp||65–115||9.5–17%|
|high pressure sodium lamp||85–150||12–22%|
|low pressure sodium lamp||100–200||15–29%|
|Ideal sources||Truncated 5800 K blackbody||251||37%|
|Green light at 555 nm (maximum possible LER)||683.002||100%|
Sources that depend on thermal emission from a solid filament, such as incandescent light bulbs, tend to have low overall efficacy compared to an ideal blackbody source because, as explained by Donald L. Klipstein, “An ideal thermal radiator produces visible light most efficiently at temperatures around 6300 °C (6600 K or 11,500 °F). Even at this high temperature, a lot of the radiation is either infrared or ultraviolet, and the theoretical luminous [efficacy] is 95 lumens per watt. Of course, nothing known to any humans is solid and usable as a light bulb filament at temperatures anywhere close to this. The surface of the sun is not quite that hot. At temperatures where the tungsten filament of an ordinary light bulb remains solid (below 3683 kelvins), most of its emission is in the infrared.
SI photometry units
|Luminous energy||Qv||lumen second||lm·s||units are sometimes called talbots|
|Luminous flux||F||lumen (= cd·sr)||lm||also called luminous power|
|Luminous intensity||Iv||candela (= lm/sr)||cd||an SI base unit|
|Luminance||Lv||candela per square metre||cd/m2||units are sometimes called "nits"|
|Illuminance||Ev||lux (= lm/m2)||lx||Used for light incident on a surface|
|Luminous emittance||Mv||lux (= lm/m2)||lx||Used for light emitted from a surface|
|Luminous efficacy||lumen per watt||lm/W||ratio of luminous flux to radiant flux|
|See also SI · Photometry · Radiometry| | physics |
https://go.galegroup.com/ps/anonymous?p=AONE&sw=w&issn=00256501&v=2.1&it=r&id=GALE%7CA254012988&sid=googleScholar&linkaccess=fulltext&authCount=1&isAnonymousEntry=true | 2023-12-03T15:01:29 | s3://commoncrawl/crawl-data/CC-MAIN-2023-50/segments/1700679100508.23/warc/CC-MAIN-20231203125921-20231203155921-00871.warc.gz | 0.922266 | 688 | CC-MAIN-2023-50 | webtext-fineweb__CC-MAIN-2023-50__0__296165165 | en | The inexorable march towards smaller, faster, and more capable electronic systems has been breathtaking. In 1946, ENIAC, the first programmable computer, housed 50,000 vacuum tubes in 80 feet of cabinetry, drew 150 kilowatts of power, and performed 5,000 operations per second. Today's off-the-shelf Pentium microprocessor jams 2 billion transistors onto a 2.2 square centimeter sliver of silicon roughly 0.3-to-O.7-millimeter thick, draws 80 watts of power, and can perform 3.2 billion operations per second.
The development of the integrated circuit, independently invented by Jack Kilby of Texas Instruments and Robert Noyce of Fairchild Semiconductor, in the late 1950s placed the information industry on this torrid pace of innovation. For the past 35 years, the number of transistors on integrated circuits has doubled approximately every two years. This doubling effect is the so-called Moore's Law, named after Intel cofounder Gordon Moore.
These thousands, then millions, and now billions of transistors switching on and off generate heat. In today's most advanced systems, silicon chips--called dies by their manufacturers--operating at 85 [degrees]C can generate average heat fluxes of more than 100 W/cm2 and produce localized, submillimeter hot spots often exceeding 1 kW/[cm.sup.2]. This is within an order of magnitude of the heat released into space by the surface of the sun. Without our ability to remove ever-greater heat fluxes from the surfaces of integrated circuits and other electronic components, we would never realize the benefits of their prodigious computational capability.
Engineers often specify air-cooled heat sinks or liquid-cooled cold plates to stabilize high-flux chips thermally. They are attached by successive layers of heat spreaders (usually copper plates that diffuse heat over a greater area) and thermal interface materials (often thermally conductive particle-filled silicones or greases).
As the performance of microprocessors has begun to approach the complexity of the human brain, the three-dimensional architecture of nature's most powerful biological computer has inspired new ways to organize dies. One promising approach is the three-dimensional chip stack. Here, adjacent chips are piled directly above one another, typically separated by 10 to 50 micrometers, rather than located next to one another and separated laterally by 10 to 50 millimeters on a printed circuit board.
There are several reasons why chip stacks will help us maintain the cadence of Moore's Law far into the future. The vertical placement of one chip on top of the other provides a third dimension of interconnected transistors and functional electronic macrocells. Such close proximity--micrometers rather than millimeters-nearly eliminates significant time delays as signals travel between chips.
Equally important, fusing chips with different functional capabilities--processing, memory, power, communications, and environmental sensing--into a single chip stack could lead to compact microsystems of unrivaled capability and truly ubiquitous computing.
Engineers have already begun to design products to leverage those advantages. Stacks of memory chips have been in commercial use for more than ten years. Yet rudimentary stacks of two or three low-power logic dies are...
This is a preview. Get the full text through your school or public library. | physics |
https://www.visitwindsorcolorado.com/event/weird-science-2/ | 2023-09-21T16:57:43 | s3://commoncrawl/crawl-data/CC-MAIN-2023-40/segments/1695233506028.36/warc/CC-MAIN-20230921141907-20230921171907-00696.warc.gz | 0.882864 | 189 | CC-MAIN-2023-40 | webtext-fineweb__CC-MAIN-2023-40__0__282053599 | en | - This event has passed.
September 29, 2022 @ 3:15 pm - 4:15 pm
Weird Science offers kids the opportunity to explore the crazy world of STEM through experimentation, teamwork, creativity, inquiry, and innovation!
The Nether portal has opened up at the library! In this session of Weird Science we will enter the world of Minecraft. We will build structures out of wood and bricks (and then destroy them), outwit the creepers in creeper toss, scavenge for materials to complete our crafting recipes, and find gemstones at the mining station.
For ages 6-12. Registration is required. Please register each child separately that will be attending the program using the child’s first and last name. We will meet in the large conference room in the Windsor-Severance Library.
Please email Diana at [email protected] with any questions. | physics |
https://fireplacefinder.com/how-do-electric-fireplace-flames-work/ | 2022-12-09T11:30:12 | s3://commoncrawl/crawl-data/CC-MAIN-2022-49/segments/1669446711396.19/warc/CC-MAIN-20221209112528-20221209142528-00077.warc.gz | 0.898752 | 683 | CC-MAIN-2022-49 | webtext-fineweb__CC-MAIN-2022-49__0__113935834 | en | Electric fireplaces have become a popular choice in homes because they provide the warmth of a fire without having to worry about ash or soot.
One of the main features of an electric fireplace is the flameless flame.
The flame is created by electricity and LED light.
This creates the illusion of a real flame, but with no cleanup.
How does an electric fireplace make flames?
This is a tricky answer.
Most electric fireplaces use different technologies to create their flame effect.
But none are real flames.
How do electric fireplace flames work?
The most popular flame effect technologies on the market today are:
- Mechanical flames: Mechanical flames are made in several ways. For most mechanical flame electric fireplaces, a drum rotates and flashes objects in front of a light. The light can be just one color or many different colors depending on the model. They then use a reflective sort of material to reflect the light from light bulbs (usually LED).
- Water vapor: Water vapor flames are often found in more realistic electric fireplaces. The flame effect is often similar to that of mechanical flames with the added effect of “smoke” made from steam from a water tank in the fireplace.
- Holographic flames: Holographic flames are state-of-the-art offerings in an electric fireplace. The fireplace basically projects real footage of fire onto the log base. You will often find that these types of fireplaces also come with crackling sound effects and laser effects to make the flames look like they are flickering.
Does an electric fireplace have real flames?
In short, no.
99% of electric fireplaces do not have a real flame.
They are the safest method for heating a room and adding ambiance at the same time.
How do electric fireplaces create realistic flames?
Electric fireplaces work by using different technologies to create the illusion of flames. Some of the most popular techniques used to achieve this are:
Thermoelectricity, halogen bulbs, LED bulbs, halogen gas, halogen light tubes, CRT projection, and lasers.
High-end brands such as Dimplex, MagikFlame and Napoleon offer the most realistic flame effects on the market.
Here are some of the most realistic flame effect electric fireplaces on the market today:
The Dimplex IgniteXL has long held the top spot for the most realistic recessed electric fireplace.
It offers various color choices for visual effects, but the warm amber glow setting provides a super realistic flame effect.
The Dimplex Opti-Myst is a fan favorite for its super realistic flame and smoke effect. It doesn’t provide heat and is made purely for visual effect.
It’s been a long-standing favorite that most people think Dimplex are yet to beat.
So if you are looking for an electric fireplace for aesthetics only, you can’t beat the Opti-Myst.
The MagikFlame Athena uses the holographic technology discussed above. It has a whopping 30 different flame effects to choose from.
If you’re looking for a centrepiece that will give you the full feeling of an electric fireplace this mantel package is a great option.
Or check out our article on the most realistic electric fireplaces for more options. | physics |
https://www.physics.ncsu.edu/people/faculty_unsal.php | 2018-07-19T13:35:52 | s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676590901.10/warc/CC-MAIN-20180719125339-20180719145339-00310.warc.gz | 0.721077 | 486 | CC-MAIN-2018-30 | webtext-fineweb__CC-MAIN-2018-30__0__42187811 | en | I mostly work on dynamics of gauge theories with applications to QCD, theoretical lattice field theory and mathematical physics. My interests to date included: Gauge theory dynamics, QCD, Resurgence theory and its applications to QFT and quantum mechanics, Picard-Lefschetz/resurgence theory of path integration, Supersymmetry on lattice, Lattice gauge theory, Large-N volume independence, Eguchi-Kawai reduction, Orbifold-orientifold equivalences, Supersymmetric gauge dynamics, Classification of topological excitations (magnetic monopoles, magnetic and neutral bions, semi-classical renormalons) and confinement mechanisms.
Select Publications | Complete List Of Publications
Deconstructing zero: resurgence, supersymmetry and complex saddles.
G. V. Dunne, M. Ünsal JHEP., 12, 1 (2016)
New Nonperturbative Methods in Quantum Field Theory: From Large-N Orbifold Equivalence to Bions and Resurgence
G. V. Dunne, M. Ünsal Annu. Rev. Nucl. Part. Sci., 66, 245-272 (2016)
Chiral Lagrangian from Duality and Monopole Operators in Compactified QCD
A. Cherman, T. Schäfer, M. Ünsal Phys. Rev. Lett., 117, 081601 (2016)
Complexified path integrals, exact saddles and supersymmetry
A. Behtash, G. V. Dunne, T. Schäfer, T. Sulejmanpasic, M. Ünsal Phys. Rev. Lett., 116, 011601 (2016)
Decoding perturbation theory using resurgence: Stokes phenomena, new saddle points and Lefschetz thimbles
A. Cherman, D. Dorigoni, M. Ünsal JHEP, 2015, Article 56 (2015)
Resurgence in Quantum Field Theory: Nonperturbative Effects in the Principal Chiral Model
A. Cherman, D. Dorigoni, G. V. Dunne, M. Ünsal Phys. Rev. Lett., 102, 021601 (2014)
Honors & Awards | physics |
https://www.hony-tools.com/products_detail/961625302831681536.html | 2023-12-02T02:06:09 | s3://commoncrawl/crawl-data/CC-MAIN-2023-50/segments/1700679100309.57/warc/CC-MAIN-20231202010506-20231202040506-00126.warc.gz | 0.733383 | 309 | CC-MAIN-2023-50 | webtext-fineweb__CC-MAIN-2023-50__0__154249433 | en | Our major products are multifunctional wire stripping pliers, de-soldering pump, long-lived soldering irons, hot melt glue guns, ferromagnetic screwdrivers, dynamoelectric screwdrivers, precision electric pliers, network tools, electronic tools kits and network tools kits, etc. At present,our products have been exported to Europe, America and Southeast Asia and won many appraisements and prizes from customers.
- Large LCD display:30x60mmLCD
- Auto power off (optional).
- DC Voltage:200m/2/20/200V±0.5%,1000V±0.8%.
- DC Current:20μA±2%,200±/2m/20mA±0.8%,200m/2A±1.5%,10A±2%.
- AC Current:200μA/200m/2A±1.8%,2m/20mA±1.0%,10A±3%.
- Resistance:200/2K/200K/2MΩ±0.8%, 20MΩ±1.0%, 200MΩ±5%.
- Continuity checking with buzzer.
- Diode check:Test current1.0mA,test voltage 2.8V.
- Power source:6F22(9V)x1
- Size: 91x189x31.5mm
- Weight: 310g(including battery) | physics |
https://mrhealthbuddy.com/product/microtek-puls-oximeter/ | 2023-03-21T07:56:30 | s3://commoncrawl/crawl-data/CC-MAIN-2023-14/segments/1679296943637.3/warc/CC-MAIN-20230321064400-20230321094400-00437.warc.gz | 0.910591 | 120 | CC-MAIN-2023-14 | webtext-fineweb__CC-MAIN-2023-14__0__194572057 | en | Pulse oximeters can help you monitor the oxygen saturation of hemoglobin in the arterial blood non invasively. Measuring oxygen saturation is as important as measuring pulse rate and hence pulse oximeters are valuable piece of equipments that can help decide oxygen flow. Working on the principle of photodetection, the pulse oximeters emit infrared rays to detect the oxygen saturation in blood. Microtek has come up with smart pulse oximeters that help you keep a check on the trend. Understand more about how they work here: Pulse Oximeter Principle
There are no reviews yet. | physics |
https://theswegway.co.uk/products/all-terrain-8-5-off-road-hoverboard-deal-of-the-day-50-off | 2023-12-11T23:08:29 | s3://commoncrawl/crawl-data/CC-MAIN-2023-50/segments/1700679518883.99/warc/CC-MAIN-20231211210408-20231212000408-00374.warc.gz | 0.81241 | 383 | CC-MAIN-2023-50 | webtext-fineweb__CC-MAIN-2023-50__0__243897984 | en | The original scooter is an intuitive, technologically advanced solution that provides the user personal transportation based on dynamic balancing principles calculating the user’s center of gravity using gyroscope and acceleration sensors.
- Self-balancing for a smooth ride
- Acceleration sensors to control speed
- Energy-saving motor for quick reaction
- Quality tested for durability
Zip around with this IconBIT Mekotron Hoverboard. Equipped with solid 8.5" wheels and advanced gravity-calculating technology for effortless balance, this hoverboard gives you a smooth and intuitive ride. Just step on and go.
Once your centre of gravity is established, acceleration sensors guide your movements, making it easy to get going. Glide forward along a path, go backwards, left and right, spin in place or just run circles around your friends.
Zig-zag along an obstacle course easily. The Mekotron Hoverboard's energy-saving motor puts you in control. Manoeuver with your body using minimum effort for maximum fun.
Each hoverboard is strictly quality tested, so you can be sure of its durable design.
SAFETY NOTICE: This product is not suitable for children 12 years old and younger. Major factors such as terrain, user weight, temperature, speed, and riding style may affect the operating range of this hoverboard.
||- Input: AC 100-240 V/50-60 Hz/0.5 A
- Output: DC 42 V/2 A
||- Digital gyroscope and acceleration sensors for control
- Motion sensor
- Silicone anti-skidding pedal
- Smart BMS
- Self-balancing 360° rotation
- Boost technology
||- IconBIT Mekotron Hoverboard
- Power supply
- User manual
||240 x 640 x 230 mm (H x W x D) | physics |
http://qxslab.cn/content/details6_2014.html | 2020-02-25T08:56:53 | s3://commoncrawl/crawl-data/CC-MAIN-2020-10/segments/1581875146064.76/warc/CC-MAIN-20200225080028-20200225110028-00059.warc.gz | 0.854177 | 347 | CC-MAIN-2020-10 | webtext-fineweb__CC-MAIN-2020-10__0__39147440 | en | Over recent years there has been tremendous interest in “Materials Processing and Manufacture in Space” and associated space experiments, but still we struggle with the related engineering applications and the scientific issues under the extreme conditions in space. Based upon this topic, Qian Lab (short for Qian Xuesen Laboratory of Space Technology, a branch of CAST) is delighted to be working in partnership with the Institute of Material Physics in Space, DLR (DLRMP) on a cooperation project of “3D printing in Space”.
We are pleased to announce that the 1st Sino-German Workshop on 3D Printing in Space hosted by Qian Lab will take place in Beijing on 20 February, 2019. Our guests from Germany are Prof. Andreas Meyer (DLRMP), Dr. Christian Neumann (DLRMP), Ms. Olfa Lopez (DLRMP), Prof. Jens Guenster (BAM), Dr. Andrea Zocca (BAM), Dr. Tao Wu (University of Kassel).
We welcome you join us in promoting the development of the scientific research and advanced technology in this area.
We look forward to seeing you in Beijing.
Date: 20 Feb, 2019
Location: Lunar Building（月球楼）, Qian Lab, Haidian, Beijing 100094, China.
Chair: Wei-Hua Wang
Co-Chair: Andreas Meyer
Local Organizing Committee
Chair: Wei-Hua Wang;
Members: Shaofan Zhao ([email protected]),
Qi Zhang ([email protected]) | physics |
http://www.maxxtexx.de/new-horizons-pluto-flyby-2015/ | 2018-11-15T14:19:05 | s3://commoncrawl/crawl-data/CC-MAIN-2018-47/segments/1542039742779.14/warc/CC-MAIN-20181115141220-20181115163220-00102.warc.gz | 0.70299 | 300 | CC-MAIN-2018-47 | webtext-fineweb__CC-MAIN-2018-47__0__118994950 | en | New Horizons Pluto Flyby 2015
Damit hätten wohl die wenigsten Planeten- Wisseschaftler gerechnet. Pluto ist wohl doch größer als zuerst angenommen und auch einer seiner Monde “ Charon “ hat es offenbar in sich. Wir bleiben auf jeden Fall an Pluto dran.
Video: New Horizons Pluto Flyby 2015
New Horizons Pluto Flyby 2015 – Powered by NASA
What have we learned so far?
The New Horizons team has already solved one of the biggest mysteries about Pluto: its size. This morning, NASA announced that Pluto is 2,370km (about 1,473 miles) in diameter, give or take 20m. That makes it ever so slightly bigger than Eris, a much darker and denser object that lives farther out in the Kuiper Belt. (Eris measures 2,336km in diameter.) Measurements of Pluto’s size before today were estimates at best, their accuracy skewed by the dwarf planet’s hazy atmosphere.
This morning also brought confirmation that Pluto has an icy polar cap, which is made of a mix of frozen methane and nitrogen gases. And while scientists had theorized that Pluto’s thin atmosphere contained nitrogen, we’ve already learned that the gas is escaping Pluto’s atmosphere much faster than expected. | physics |
https://dcwort.co.za/silicon-mica.html | 2023-12-03T17:28:18 | s3://commoncrawl/crawl-data/CC-MAIN-2023-50/segments/1700679100508.42/warc/CC-MAIN-20231203161435-20231203191435-00390.warc.gz | 0.885505 | 295 | CC-MAIN-2023-50 | webtext-fineweb__CC-MAIN-2023-50__0__189760304 | en | Mica possesses exceptional properties resisting everything from fire, electricity, chemicals to radiation and at the same time is environmentally safe. Rigid mica sheets consiststing of muscovite or phlogopite mica impregnated with a high temperature silicon binder have unique dielectric, thermal and mechanical properties. Superior in intensity, incombustibility and are flame resistant withstanding temperatures up to 800°C. Applications include but are not limited to thermal protection barriers where mechanical strength and high compression and pressure at high temperature is involved. As insulation between high temperature heated platens and moulds in hydraulic and forging presses. As high temperature insulation of electrode arms and buss-bars in electrical, induction and arc furnaces. Innumerable other uses.
Flexible mica sheets or rolls consisting of muscovite or phlogopite mica impregnated with a high temperature silicon binder are available plain or laminated with glass cloth or ceramic felt. Temperature resistant up to 1000°C (phlogopite). Mainly used as slip plane insulation between the crucible and induction coil in induction furnaces but with a wide variety of other uses.
Mica plates are laminates used in extreme conditions, this product has good properties like high heat resistance, flame resistance, low thermal conductivity, high mechanical strength, easy machineability, good electrical properties, low sensitivity to chemicals, Asbestos free and non-toxic. | physics |
https://pearlsformen.com/en-ca/blogs/news/how-do-automatic-watches-work | 2024-04-13T22:32:30 | s3://commoncrawl/crawl-data/CC-MAIN-2024-18/segments/1712296816853.44/warc/CC-MAIN-20240413211215-20240414001215-00037.warc.gz | 0.938363 | 2,386 | CC-MAIN-2024-18 | webtext-fineweb__CC-MAIN-2024-18__0__162908953 | en | Have you ever wondered how automatic watches work? Well, let me tell you, it's a fascinating blend of craftsmanship and engineering that keeps these timepieces ticking! Automatic watches, also known as self-winding watches, are a marvel of ingenuity. They don't rely on batteries or manual winding to keep time; instead, they harness the natural movement of your wrist to power their intricate mechanisms.
So, how do automatic watches work their magic? Inside these timekeeping wonders, you'll find a tiny rotor that swings back and forth with the motion of your wrist. This rotor is connected to a series of gears and springs, which ultimately wind the watch's mainspring. The mainspring is like the heart of the watch, storing up energy to keep the gears turning and the hands moving. It's a delicate dance of precision engineering, where every component works in harmony to ensure accurate timekeeping.
The beauty of automatic watches lies in their ability to be self-sustaining. As long as you wear the watch regularly, the natural motion of your arm will keep the rotor spinning, continually winding the mainspring and keeping the watch running smoothly. But don't worry if you take the watch off for a day or two – many automatic watches have a power reserve that allows them to keep ticking for a certain period, even when not in use. So, whether you're a watch enthusiast or simply curious about the inner workings of these timekeeping marvels, understanding how automatic watches work is sure to leave you in awe of the craftsmanship and engineering behind them.
How do Automatic Watches Work?
Automatic watches, also known as self-winding watches, are a marvel of engineering and craftsmanship. These timepieces have captivated watch enthusiasts and collectors for decades, offering a combination of elegance, precision, and convenience. In this article, we will explore the inner workings of automatic watches, shedding light on the intricate mechanisms that power these remarkable timekeeping devices.
History of Automatic Watches
Automatic watches have a rich history that dates back to the late 18th century. The invention of the self-winding mechanism is often attributed to Swiss watchmaker Abraham-Louis Perrelet, who introduced the first automatic pocket watch in 1770. However, it wasn't until the early 20th century that automatic watches gained widespread popularity, thanks to advancements in technology and the evolving demands of watch enthusiasts.
The Rotor: A Key Component
At the heart of every automatic watch is a rotor, a weighted mechanism that rotates with the natural movement of the wearer's arm. The rotor is connected to the mainspring, which stores the energy needed to power the watch. As the wearer moves, the rotor spins, transferring energy to the mainspring through a series of gears and levers. This continuous motion ensures that the watch remains wound and keeps accurate time.
The design of the rotor has evolved over the years, with different watch manufacturers incorporating their unique variations. Some rotors are unidirectional, meaning they only rotate in one direction, while others are bidirectional, allowing them to rotate in both directions. Additionally, modern automatic watches often feature transparent case backs, allowing wearers to admire the intricate movements of the rotor and other components.
The Mainspring and Gear Train
The mainspring is a vital component of an automatic watch. It is a coiled spring that stores potential energy when wound and releases it slowly to power the movement of the watch. The energy stored in the mainspring is transferred to the gear train, a series of gears and wheels that transmit the energy throughout the watch.
The gear train consists of several gears with different sizes, each playing a crucial role in regulating the movement of the watch. The escapement wheel, for example, controls the release of energy from the mainspring, while the balance wheel oscillates back and forth, creating the familiar ticking sound and ensuring the accuracy of the timekeeping.
The Escapement Mechanism
The escapement mechanism is another critical component of automatic watches. It regulates the release of energy from the mainspring in precise intervals, allowing the watch to keep accurate time. The most common type of escapement used in automatic watches is the Swiss lever escapement, known for its reliability and efficiency.
The Swiss lever escapement consists of an escape wheel, a pallet fork, and an impulse jewel. As the escape wheel rotates, it pushes against the pallet fork, which in turn locks and unlocks the escape wheel. This locking and unlocking action transfers energy to the balance wheel, causing it to oscillate and regulate the movement of the watch.
Benefits of Automatic Watches
Automatic watches offer several advantages over their quartz counterparts. First and foremost, they are powered by mechanical movements, which are often regarded as more prestigious and traditional. Additionally, automatic watches do not require battery replacements, as they are self-winding through the wearer's natural movements. This convenience eliminates the need for regular maintenance and ensures that the watch is always ready to be worn.
Furthermore, automatic watches are often crafted with exceptional attention to detail, featuring intricate dials, polished cases, and high-quality materials. These timepieces can become treasured heirlooms, passed down through generations, and appreciated for their timeless beauty and mechanical complexity.
Care and Maintenance
To keep an automatic watch in optimal working condition, regular care and maintenance are essential. It is recommended to have the watch serviced by a professional every three to five years to ensure that all components are in good working order. Additionally, it is important to store the watch in a watch box or case when not in use to protect it from dust, moisture, and potential damage.
In conclusion, automatic watches are a testament to the artistry and precision of watchmaking. From the rotating rotor to the intricate gear train and escapement mechanism, each component works harmoniously to power these remarkable timepieces. Whether you are a watch enthusiast or simply appreciate the craftsmanship of fine mechanical watches, understanding how automatic watches work adds a new level of appreciation for these timeless accessories.
Key Takeaways: How do automatic watches work?
- Automatic watches are powered by the natural motion of the wearer's arm.
- Inside the watch, there is a rotor that spins with the movement of the arm.
- This rotor transfers energy to a mainspring, which stores the energy.
- As the mainspring unwinds, it releases energy to power the watch's movement.
- Automatic watches don't require batteries or manual winding, making them convenient and low-maintenance.
Frequently Asked Questions
How does the mechanism of an automatic watch work?
An automatic watch operates using a mechanical movement that harnesses the natural motion of the wearer's arm. Inside the watch, there is a rotor that spins with each movement of the wrist. This rotor is connected to the mainspring, which stores the energy needed to power the watch. As the rotor rotates, it winds up the mainspring, providing the watch with a constant source of energy.
When the mainspring is fully wound, it slowly unwinds over time, releasing the stored energy and powering the watch's mechanism. This energy is transferred through a series of gears and springs that control the movement of the hands and other complications on the watch dial. The precision of these components ensures accurate timekeeping and the smooth operation of the watch.
What is the power reserve of an automatic watch?
The power reserve of an automatic watch refers to the length of time it can run without being worn or wound. The power reserve can vary depending on the specific watch model and movement, but it typically ranges from 24 to 48 hours. This means that if you take off your automatic watch and leave it unworn for the specified power reserve duration, it will stop running.
To keep an automatic watch running, it is recommended to wear it regularly or use a watch winder, which mimics the motion of the arm to keep the watch wound. Additionally, manually winding the watch by turning the crown can also provide a power boost and keep the watch running when it is not being worn.
Are automatic watches accurate?
Automatic watches are generally considered to be accurate timepieces, but their accuracy can vary depending on several factors. The precision of an automatic watch movement is influenced by the quality of its components, the craftsmanship of its assembly, and the regularity of maintenance and servicing.
While most modern automatic watches are designed to keep time within a few seconds per day, there may be slight variations due to external factors such as temperature, magnetism, and the position in which the watch is worn. Regular calibration and adjustment by a professional watchmaker can help ensure optimal accuracy.
Can you overwind an automatic watch?
No, it is not possible to overwind an automatic watch. Unlike manual-winding watches, automatic watches have a mechanism that prevents overwinding. Once the mainspring is fully wound, the rotor will stop rotating, and the watch will no longer wind itself. This mechanism ensures that the watch is not subjected to excessive tension, preventing damage to the movement.
It is important to note that even if you continue to move your wrist while wearing an automatic watch, the winding mechanism will not overwind the watch. The watch will simply maintain its power reserve and continue to operate as usual.
Do automatic watches require regular maintenance?
Yes, automatic watches do require regular maintenance to ensure their longevity and optimal performance. Over time, the lubricants inside the movement can degrade, and dust or debris may accumulate, affecting the watch's accuracy and functionality.
It is recommended to have an automatic watch serviced by a professional watchmaker every three to five years. During a routine service, the watch will be disassembled, cleaned, and lubricated. The watchmaker will also inspect the movement for any potential issues and make any necessary adjustments or repairs. Regular maintenance helps prolong the lifespan of the watch and ensures it continues to operate smoothly.
How Does An Automatic Watch Work? - Patek Philippe 5180 | Watchfinder & Co.
Final Summary: How Do Automatic Watches Work?
So there you have it, a fascinating glimpse into the inner workings of automatic watches. These remarkable timepieces are a perfect blend of engineering marvel and timeless elegance. With their intricate mechanisms and self-winding capabilities, automatic watches offer a unique and captivating experience for watch enthusiasts and casual wearers alike.
In conclusion, automatic watches rely on the natural motion of the wearer's wrist to power their mechanisms. Through the use of a rotor, which spins with the movement of the wrist, the watch's mainspring is wound, storing potential energy. This energy is then transferred to the escapement, regulating the release of power and ensuring accurate timekeeping.
But it's not just about functionality; automatic watches are also a symbol of craftsmanship and style. With their intricate dials, luxurious materials, and exquisite details, these timepieces are not just accessories, but works of art that can be passed down through generations. So, whether you're a watch enthusiast or simply appreciate the beauty of a finely crafted timepiece, automatic watches are sure to capture your heart and stand the test of time.
Remember, wearing an automatic watch is more than just telling time. It's about embracing tradition, appreciating the artistry of horology, and connecting with a piece of history on your wrist. So, next time you slip on your automatic watch and feel the gentle motion of the rotor, take a moment to appreciate the ingenuity and craftsmanship that goes into making these remarkable timekeeping companions. | physics |
https://jamesbradbury.xyz/annealing-strategies | 2018-12-10T00:36:38 | s3://commoncrawl/crawl-data/CC-MAIN-2018-51/segments/1544376823228.36/warc/CC-MAIN-20181209232026-20181210013526-00366.warc.gz | 0.86506 | 236 | CC-MAIN-2018-51 | webtext-fineweb__CC-MAIN-2018-51__0__40947291 | en | This system optimises and searches a chaotic parameter space using the process of simulated annealing. This algorithm mimics the physical mechanism of gradually cooling metal in order to remove internal stresses and strengthen it. This process is similar to a hill climbing algorithm, with the addition of a 'temperature' coefficient that allows for local minima and maxima to be escaped from. Random decisions are allowed with respect to this coefficient, meaning the system is volatile and explorative at high temperatures and more conservative at low temperatures. As the system is cooled the system hones in on an optimised solution.
A single input value is used which is mapped onto a three-dimensional parameter space. The sound generating guts of the system are a digital emulation of Peter Blasser's (Ciat-Lonbarde) fourses algorithm. This engine takes 24 parameters, which are reduced in dimensionality to a single input. The output of the system is measured in decibels according to a perceptual loudness descriptor. The sim-annealing algorithm attempts to find at which input parameter the quietest output is produced. The system's agency is its exploratory journey to an optimised solution. | physics |
https://sheslookingatthestars.com/skin-diseases/you-asked-what-is-the-energy-of-one-mole-of-photons.html | 2022-05-16T22:47:05 | s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662512249.16/warc/CC-MAIN-20220516204516-20220516234516-00424.warc.gz | 0.900763 | 955 | CC-MAIN-2022-21 | webtext-fineweb__CC-MAIN-2022-21__0__22784605 | en | The equation used to find the energy in a mole of photons is E= hc/lambda where h is Planck’s constant, c is the speed of light and is the wavelength of light. The value of E will come out in units that are useful for us to work with if we put the constants and wavelength in the proper units.
What is the energy of 1 mole of photons?
The energy of photon is the energy carried by 1 mole of photon. It is directly proportional to the frequency of the electromagnetic radiation where the proportionality constant is the Planck’s constant (h). The value of Planck’s constant is 6.626×10−34 Js 6.626 × 10 − 34 J s .
What is the energy of one photon?
The energy of a single photon is: hν or = (h/2π)ω where h is Planck’s constant: 6.626 x 10-34 Joule-sec. One photon of visible light contains about 10-19 Joules (not much!) the number of photons per second in a beam.
What is the energy of one mole of photons of radiation whose frequency is?
= 199.51 kJ mol−1.
What is the energy of one mole of photons with 540 nm?
The energy of 1 mole of the photon is 3.68 × 10–19 J.
How do you find the energy of a photon?
Energy of a Photon
The amount of energy in those photons is calculated by this equation, E = hf, where E is the energy of the photon in Joules; h is Planck’s constant, which is always 6.63 * 10^-34 Joule seconds; and f is the frequency of the light in hertz.
What is a mole of photons?
From Wikipedia, the free encyclopedia. The einstein (symbol E) is a unit defined as the energy in one mole of photons (6.022×1023 photons). Because energy is inversely proportional to wavelength, the unit is frequency dependent.
How much energy is 3 moles photons?
Each photon has an energy of 2.9450×10–19 J. 1 mol of a photon has 6.022×1023 photons. The answer is option A), In 3.00 moles of photons with a wavelength of 675 nm, the energy is 532 kJ.
What is the energy of a mole of these photons 325 nm?
Energy of 1 mole of photons is: c) Number of photons in 1 mJ of radiation is calculated by dividing total energy with the energy of one photon: d) Average energy of chemical bonds (in human skin equals the energy of photons with 325 nm wavelength, which is already calculated to be 3.68×105 J/mol which is 368 kJ/mol.
What is the energy of a photon with a frequency of 5×10 14 Hz?
Explanation: h is Planck’s Constant, f is the frequency, c is the speed of light, and λ is the wavelength of the radiation. Calculate the energy of a photon of radiation whose frequency is 5.00×1014Hz . The energy is 3.31×10−19J .
What is the kinetic energy of a photoelectron emitted when radiation of frequency?
The maximum kinetic energy of photoelectrons ejected from a metal, when it is irradiated with radiation of frequency 2×1014s−1 is 6. 63×10−20J.
What is the energy associated with one mole of radiation of wavelength 10 3?
How many joules is a photon?
It should not surprise us that the energy of a single photon is small. It is also useful to calculate the number of photons in a Joule of energy. This is just the inverse of the energy per photon, and gives 3.2×1018 photons per Joule.
What is the energy of a mole of photons that have a wavelength of 725 nm?
Um energy is equal to H. C. Over the wavelength 6.626 times 10 to the negative 34. Multiplied by the speed of light three times 10 to the 8th Over our wavelength 7.25 times 10 to the -7. And so the energy is going to be 2.7, 4 Times 10 to the -19 Joules Per Photon.
What is the energy of one 266 nm photon in joules? | physics |
http://www.kns.com/en-us/Pages/Orthodyne%20Sites.aspx | 2017-10-17T22:02:19 | s3://commoncrawl/crawl-data/CC-MAIN-2017-43/segments/1508187822513.17/warc/CC-MAIN-20171017215800-20171017235800-00731.warc.gz | 0.913297 | 191 | CC-MAIN-2017-43 | webtext-fineweb__CC-MAIN-2017-43__0__52236025 | en | Orthodyne Wedge Bonders are the leader in wire and ribbon bonding for power semiconductors, automotive power modules and industrial power hybrids. Orthodyne bonders ultrasonically bond round aluminum wires from 25 to 500 microns in diameter (1-20 mils) and use the PowerRibbon process to ultrasonically bond aluminum ribbons from 500x100 to 2000x300 microns in cross-section (20x4 - 80x12 mils).
For over 45 years, Orthodyne products have been recognized for exceptional performance, reliability, and excellent after-sales support. Orthodyne has won many awards for excellent customer service. The Wire Bonders are created to cater to industries in need of smaller, thinner and denser semiconductor packages.
Orthodyne joined the K&S team in October 2008 to become the wedge bonder business line of Kulicke & Soffa. | physics |
https://chipress.co/2019/03/23/what-are-static-power-and-dynamic-power/ | 2021-03-07T21:59:25 | s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178378872.82/warc/CC-MAIN-20210307200746-20210307230746-00154.warc.gz | 0.892168 | 231 | CC-MAIN-2021-10 | webtext-fineweb__CC-MAIN-2021-10__0__168421002 | en | Static power is the circuit leakage power. Static power exists even if there is no activities. When power is applied to the transistors, transistors would leak current naturally due to physical characteristics of the silicon and manufacturing defects. Examples of static power include transistor drain to source leakage and silicon substrate leakage.
Dynamic power is the power used to charge or discharge transistor intrinsic capacitor. Dynamic power only exists when signals toggle either from low-to-high or high-to-low. For example, clock toggles every cycle, thus clock paths consumes huge amount of dynamic power if there is no clock gating.
Short-circuit dissipation power occurs when both NMOS and PMOS transistors are active for a small period of time, during which current will find a path directly from power rail to ground. Hence, this creates a short-circuit current. In first-order analysis, we assume 0 transistor rise / fall time during transition, and short-circuit dissipation power can be ignored. However, we shall assume finite transistor transition time in more accurate analysis, thus short-circuit dissipation power exists every time signal toggles. | physics |
http://direct.skinnerinc.com/auctions/2283/lots/1239 | 2020-08-05T18:40:24 | s3://commoncrawl/crawl-data/CC-MAIN-2020-34/segments/1596439735964.82/warc/CC-MAIN-20200805183003-20200805213003-00391.warc.gz | 0.968569 | 345 | CC-MAIN-2020-34 | webtext-fineweb__CC-MAIN-2020-34__0__2788375 | en | Edison Fluoroscope No. 588, with tapering leather-covered wood body, rear 4 1/2 x 6 1/2-inch ground-glass screen, viewing hood with felt eye-pad, and turned wood handle, lg. 9 in.; and a Look Parallax Panoramagram (three-dimensional photograph) showing a bust of Thomas Edison surrounded by five of his key inventions: the electric lamp, stock-ticker, motion-picture projector, phonograph and fluoroscope.
Note: Within weeks of Wilhelm Conrad Rontgen publishing his report "On a New Kind of Rays" on December 28th 1895, the news of his discovery of X-rays had spread around the world. In 1896, Thomas Edison, realizing the potential medical uses, began work on the fluoroscope as a means of viewing X-ray images. Edison's invention featured a hand-held leather-covered box resembling a contemporary stereoscope, with a viewing screen made out of tungstate of calcium (replaced on this example with ground-glass). Unusually, Edison chose not to patent his device, preferring to leave it in the public domain for immediate medical application; the fluoroscope was soon put to use by surgeons performing the first X-ray operations in America.
Unfortunately this new radiation had other effects on the people who experimented with it. The electrical engineer Elihu Thomson deliberately exposed one of his fingers to X-rays in order to observe the resultant burns. Edison's assistant Clarence Dally was also affected and eventually died as a result of radiation. Maybe it was as a result of these and other early casualties that few examples of the Edison fluoroscope are thought to have survived. | physics |
https://svc.osu.edu/news/2019/08/prof.-vicky-doan-nguyen-awarded-40k-through-osu-materials-research-seed-grant-program | 2023-06-05T22:43:33 | s3://commoncrawl/crawl-data/CC-MAIN-2023-23/segments/1685224652184.68/warc/CC-MAIN-20230605221713-20230606011713-00694.warc.gz | 0.895695 | 271 | CC-MAIN-2023-23 | webtext-fineweb__CC-MAIN-2023-23__0__138629854 | en | Prof. Vicky Doan-Nguyen awarded $40K through OSU Materials Research Seed Grant Program
The Ohio State University this week announced seven innovative materials research projects will receive a total of $300,000 in funding through the OSU Materials Research Seed Grant Program.
The program seeds and advances excellence in materials research of varying scopes. It is jointly funded and managed by the Institute for Materials Research (IMR), Center for Emergent Materials (CEM) and Center for Exploration of Novel Complex Materials (ENCOMM). The program furthers IMR's mission to nurture, grow and support excellence in materials research. The enhanced OSU Materials Research Seed Grant Program became available to the Ohio State materials community on Winter 2011.
This year, one Multidisciplinary Team Building Grant (MTBG) and six Exploratory Materials Research Grant (EMRG) awards were selected after a thorough internal and external review. This grant assists in enabling nascent and innovative materials research to emerge to the point of being competitive for external funding. Each award is $40,000.
Prinicipal Investigator: Vicky Doan-Nguyen, joint appointment in Materials Science and Engineering and Mechancial and Aerospace Engineering
Project Topic: Design and Local Structure Identification of Stable Electrode-Electrolyte Interfaces
Click here for full article. | physics |
https://www.jascofrance.fr/chromatographie/consommables/colonnes/sepax/srt/ | 2024-04-16T13:28:56 | s3://commoncrawl/crawl-data/CC-MAIN-2024-18/segments/1712296817095.3/warc/CC-MAIN-20240416124708-20240416154708-00777.warc.gz | 0.841326 | 155 | CC-MAIN-2024-18 | webtext-fineweb__CC-MAIN-2024-18__0__133045057 | en | Utilizing proprietary surface technologies, SRT SEC phases are made of the uniform, hydrophilic, and neutral nanometer thick films chemically bonded on the high purity and enhanced mechanical stability silica. This proprietary surface technology results in excellent column-to-column reproducibility. The nature of the chemical bonding and the maximum bonding density of the thin film benefit SRT SEC phases with high stability and negligible non-specific interactions. Along with the widest pore size selection of 100, 150, 300, 500, 1000 and 2000Å, SRT SEC packings have highest capacity that enables highest resolution.
- Uniform, nanometer thick molecule layer
- Chemically bonded to silica surface
- Maximum bonding density | physics |
http://www.crazell.com/2016/11/23/what-are-the-advantages-of-lithium-ion-batteries-compared-to-other-rechargeable-batteries/ | 2020-08-07T08:47:21 | s3://commoncrawl/crawl-data/CC-MAIN-2020-34/segments/1596439737172.50/warc/CC-MAIN-20200807083754-20200807113754-00064.warc.gz | 0.962118 | 247 | CC-MAIN-2020-34 | webtext-fineweb__CC-MAIN-2020-34__0__66017495 | en | What are the advantages of Lithium Ion batteries compared to other rechargeable batteries?zs
Lithium-ion batteries have several advantages: They have a higher energy density than most other types of rechargeables. This means that for their size or weight they can store more energy than other rechargeable batteries. They also operate at higher voltages than other rechargeables, typically about 3.7 volts for lithium-ion vs. 1.2 volts for NiMH or NiCd. This means a single cell can often be used rather than multiple NiMH or NiCd cells. Lithium-ion batteries also have a lower self discharge rate than other types of rechargeable batteries. This means that once they are charged they will retain their charge for a longer time than other types of rechargeable batteries. NiMH and NiCd batteries can lose anywhere from 1-5% of their charge per day, (depending on the storage temperature) even if they are not installed in a device. Lithium-ion batteries will retain most of their charge even after months of storage. So in summary; lithium-ion batteries can be smaller or lighter, have a higher voltage and hold a charge much longer than other types of batteries. | physics |
https://literajapan.com/20190808 | 2024-04-16T16:47:11 | s3://commoncrawl/crawl-data/CC-MAIN-2024-18/segments/1712296817103.42/warc/CC-MAIN-20240416155952-20240416185952-00041.warc.gz | 0.934501 | 212 | CC-MAIN-2024-18 | webtext-fineweb__CC-MAIN-2024-18__0__96380948 | en | Nishizawa has contributed to the conference as a plenary speaker and her paper is found in pages 135-152.
Human and Organizational Aspects of Assuring Nuclear Safety – Exploring 30 Years of Safety Culture Proceedings of an International Conference Held in Vienna, Austria, 22-26 February 2016
These proceedings present the outcome of an international conference, at which the nuclear community had the opportunity to reflect on the pivotal role that human and organizational aspects play in assuring nuclear safety.
Held 30 years after the Chernobyl accident which led to the international adoption of the concept of safety culture, the conference provided distinguished experts and practitioners with a unique opportunity to share insights from the past and visions for a safer future. The publication contains the conference opening and closing addresses, summaries of all conference sessions as well as the fully edited papers produced for the conference plenary sessions. The papers presented at the parallel sessions and dialogue sessions of the conference are included in their original form in the CD-ROM accompanying the publication.
Electronic version can be found: | physics |
https://dencell.com/new-release-adens-1xx-density-meter/ | 2023-12-09T02:35:36 | s3://commoncrawl/crawl-data/CC-MAIN-2023-50/segments/1700679100781.60/warc/CC-MAIN-20231209004202-20231209034202-00537.warc.gz | 0.891935 | 457 | CC-MAIN-2023-50 | webtext-fineweb__CC-MAIN-2023-50__0__215137378 | en | aDENS-1xx Density Meter
Highly accurate Resonant (Vibration) Type Density Meter for in-tank or in-line measurements.
A family of Vibration Type Density Meters
aDENS-1xx Density Meter is a family of vibration type density meters intended for in tank or in-line measurements of liquids in a variety of industries, such as Oil and Gas, Liquor, Food Industries, etc. Due to high accuracy of the vibration type method they are extremely well suited for measurement of light and crude oils, petroleum products, ethanol, liquified petroleum gases (LPG) and other liquid products.
aDENS-1xx Density Meters provide real-time measurements of the following parameters:
Single point and Multi-point measurements for in-tank applications
aDENS-100/110 Density Meters for single point in-tank measurements
aDENS-100 and aDENS-110 Density Meters are intended for single point in-tank measurements. The Density Meter contains a sensor, an elongation stem with a process connection flange and an electronic head. The length of the stem supplied with the Density Meter is chosen based on the desired immersion depth of the sensor into the tank. The client can further adjust the immersion depth by moving the process connection flange along the stem.
aDENS-100/110 Density Meters are ATEX certified to II 1/2 G Ex ia IIB T4 Ga/Gb with the sensor designated for Zone 0 and the electronic head designated for Zone 1.
aDENS-120 Density Meter for multi-point in-tank measurements
aDENS-120 Density Meter is intended for multi-point measurements. The density sensor is suspended into the tank using cords or chains connected to the process connection flange.
On aboveground tanks, a chain of up to 5 sensors can be installed at different heights to measure density distribution with height as well as the average density in the tank.
aDENS-120 Density Meters are ATEX certified to II 1 G Ex ia IIB T4 Ga with the sensor with encapsulated electronics designated for Zone 0. | physics |
https://www.ultracleansystems.com/press-release-january-1-2011/ | 2022-07-02T13:58:53 | s3://commoncrawl/crawl-data/CC-MAIN-2022-27/segments/1656104141372.60/warc/CC-MAIN-20220702131941-20220702161941-00038.warc.gz | 0.932449 | 557 | CC-MAIN-2022-27 | webtext-fineweb__CC-MAIN-2022-27__0__259258035 | en | For Immediate Release:
An exclusive, new and fully functional Ultrasonic Delivery Technology for the healthcare industry has been launched by Ultra Clean Systems Inc., a Florida‐USA company, one of the leading names in ultrasonic cleaning systems.
Ultra Clean Systems, Inc. launched a new technology for the healthcare industry called “TRT (Titanium Rod Transducer) technology” with exclusive features like 13 minute cleaning cycles, direct‐in‐water energy injection and tripling the life of the system.
An exclusive, new and fully functional technology for the healthcare industry.
Ultra Clean Systems, Inc., launched a new technology for establishing a more efficient standard of ultrasonic cleaning in the healthcare industry. What makes TRT Technology special is its energy’s ability to be transferred equally in all directions, thereby preventing any ‘cold spots’ commonly cited in standard (bonded transducer) ultrasonics. Standard ultrasonics passes their energy through the transducer, the bonding agent, through the metal basin and finally, into the water. The power lost in that process is around 20%. There is no power lost in the new TRT technology. Since the system is not losing power in the process, the cleaning cycle time has been reduced by five (5) minutes and completely eliminates the need for degassing, for a total time reduction of ten (10) minutes.
“Our TRT Technology can lead to new industry standard for increased efficiencies, reduced costs and expedited cleaning of surgical instruments” according to Mr. Keith Cale, Director of Sales & Marketing for Ultra Clean Systems, Inc.
TRT Technology provides several key benefits, including:
Superior Cavitation: TRT Technology delivers better cavitation than standard (bonded transducer) ultrasonics by its exclusive direct‐in‐water energy injection.
Elimination of Energy Loss, wear & tear: The rod is a submersible transducer that directly injects the energy to the water in the basin, eliminating a vast amount of energy loss as well as wear and tear on moving or stressed parts.
Super Quick Cycle Times: Cycle times from start to finish as quickly as 13 minutes for short washes and 18 minutes for long washes.
Elimination of ‘Cold Spots’ / Consistent Energy Efficiency: TRT Technology radiates in all directions, not just in one. This means every surface area of every item you put into the tank is exposed to powerful TRT cleaning action, guaranteeing smooth and effective cleaning.
Cost‐Effective: Still the best value on the market for this powerful, productive and fast cleaning system. | physics |
https://www.meadendowment.org/vaman-diana | 2019-10-18T21:26:05 | s3://commoncrawl/crawl-data/CC-MAIN-2019-43/segments/1570986684854.67/warc/CC-MAIN-20191018204336-20191018231836-00135.warc.gz | 0.958802 | 915 | CC-MAIN-2019-43 | webtext-fineweb__CC-MAIN-2019-43__0__217815284 | en | Diana Vaman / Physics
In the Spring of 2012 semester, I will be teaching a course titled “Introduction to String Theory” (PHYS 5120). This is a course which is not offered regularly, and last time I taught it was three years ago. To my surprise, a few undergraduate students from my Quantum Physics I class, found out about it, and asked me to teach it again. They told me that there are already 6 undergraduate students who would like to take this “Introduction to String Theory” class, if given the chance. Of course, I said, I would be delighted to do it. This subject is closely related to my research which connects particle physics to strings and black holes. In broad strokes, my research concerns the fundamental structure of matter: the elementary particles and their interactions. According to the Standard Model of Particle Physics, the interactions between quarks (elementary particles which make up the nucleus’s constituents, the proton and neutron, as well as other composite particles like pions) are described by the theory of strong interactions. This theory is notoriously difficult to solve analytically. A new approach is based on the remarkable idea that precisely when the interactions between particles are strong, a dual description becomes available, in the guise of a theory of gravity/strings in extra dimensions, where the interactions are now weak and analytic results are possible. At finite temperature, a plasma of strongly interacting particles is the hologram of a black hole. This is the theoretical playground of my research.
For my Mead program “Dream Idea”, I would like to propose further developing this course. There is already a textbook (by B. Zwiebach from MIT) which makes string theory formalism accessible to an advanced undergraduate audience. However, I would like to give the students the opportunity to pick a few string-theory related topics of their choice, and, after a rigorous introduction in the subject, spend a few lectures talking about the topics they chose. I look forward to find out what topics they want to hear about, since these must have captured their imagination, and prompted them to learn a rather difficult subject.
Since this is intended as an advanced level class, the course will end with each student giving a presentation. Based on this presentation, class performance and homework, the best student(s) will be given the opportunity to participate in one of conferences organized by the American Physical Society (SESAPS Fall 2012 meeting, or Future of Physics meeting; the latter are organized in the Spring only), or do research over the summer with me. Participation in an APS conference can serve a dual purpose: if the students already have some research results to report, then they have a forum to disseminate their findings.
On the other hand, if the students are just beginning their research, they can still attend the conference and draw benefits from it. The “Future of Physics” conferences are specifically aimed at an undergraduate audience; besides undergraduate research talks, there are round tables with senior researchers, where the students can learn firsthand about the professional trajectory of people who found a calling and a career in Physics. They will also meet and interact with students from other universities. The SESAPS meetings are regional meetings with participants from South-East universities. There are overview lectures and advanced research talks in various Physics sub-fields, and, as well as graduate and undergraduate student talks. The Fall 2011 SESAPS meeting is in Roanoke, organized by Virginia Tech. The Fall 2012 host university has not been decided yet.
Alternatively, the students can choose to do Summer research with me, after completing the “Introduction to String Theory” course. Summer research is a structured activity; the students are given a topic to study and an adequate research project. We will meet weekly (once or twice) for the duration of Summer. The student(s) will get the chance to continue their study, and hopefully contribute to a research paper.
The budget for my “Dream Idea” is as follows: one or two $1200 summer research stipend(s); alternatively, $1500 travel and accommodations for two students to a regional APS conference. In addition, I would like to request up to $500 to be used for an end-of-semester “Strong Correlations” dinner. [The title is a play on my research, where correlations in strongly coupled systems are computed using the unraveled hologram: gravity in extra dimensions.] | physics |
http://christycomposite.ru/the-mythology-of-modern-dating-methods-4964.html | 2019-08-25T20:11:43 | s3://commoncrawl/crawl-data/CC-MAIN-2019-35/segments/1566027330800.17/warc/CC-MAIN-20190825194252-20190825220252-00192.warc.gz | 0.938199 | 435 | CC-MAIN-2019-35 | webtext-fineweb__CC-MAIN-2019-35__0__72983810 | en | The mythology of modern dating methods
If an art object is manufactured by melting of gold, the helium produced by the decay of uranium and thorium since the gold existed is degassed.After the gold cooled down, helium is stored again within the crystal lattice.Furthermore, only few milligrams of gold material of the valuable objects are available.We applied the U, Th–He method to numerous antique gold objects and to some forgeries by referring to the story of the gold tiara acquired for a large sum of money on April 1 (! The tiara had allegedly given more than two thousand years ago to the Scythian king Saitapharnes as part of a bribe not to attack the Greek colony of Olbia.The same method can be applied to antique gold objects for which the time of manufacturing is unknown.This research and application to gold antiquities is important because gold is probably the most difficult material in terms of detecting modern forgeries, as no patina is formed on its surface.Usually we obtain a sample of about 30 mg of an antique object for the determination of its authenticity.The sample is cleaned and etched in aqua regia in order to remove possible superficial pollution.
The feasibility of this application was mentioned in 1996 in an earlier article in Gold Bulletin, Eugster (Gold Bull 1–104, ).We show that our results indicate that the applied dating method opens a new perspective for the dating of gold deposits without assuming contemporaneity between gold and datable hydrothermal minerals.The second application of our dating method is authenticating archeological gold objects.Based on these studies we suggested that it might be possible to apply the U/Th–He dating method to antique gold objects.Inspired by our work, Kossolapov and coworkers used a specifically designed mass spectrometer for extremely low helium quantities to test gold samples of archeological (Maikop and Scythian Collections of the Hermitage Museum, St. Samples of about 50 mg of gold material were loaded into a molybdenum crucible and heated up to the melting point of gold of 1064 °C. | physics |
https://www.fielco.com/446-2/ | 2023-09-28T07:52:26 | s3://commoncrawl/crawl-data/CC-MAIN-2023-40/segments/1695233510368.33/warc/CC-MAIN-20230928063033-20230928093033-00563.warc.gz | 0.915384 | 742 | CC-MAIN-2023-40 | webtext-fineweb__CC-MAIN-2023-40__0__162553599 | en | By Tony Ring, technical director Fielco Adhesives. Huntingdon Valley, PA
In the March issue we discussed ways to use specialized instruments – the Brookfield cone-plate digital rheometer and the Aquastar titrator – for answering specific customer concerns. Continuing with this series, this article discusses two more instruments, the dielectric analyzer and the differential scanning calorimeter. In each case, a high technology product required a specific test with these instruments. The series will conclude in the October issue.
Differential Scanning Calorimeter
The differential scanning calorimeter measures both the temperature and heat flow associated with material transitions. The operator determines heat and temperature values required by a specific manufacturing operation and then sets the instrument, which works as a small, precise oven. This oven can be used to control chamber conditions from -170ºC to 725ºC, within 0.1º. We have used this equipment often to determine the glass transition of a polymer, which is the point where the material changes from a rigid piece to a rubbery material. This value is an excellent indicator of the temperature range in which the mechanical properties of a test material will remain constant.
Fielco uses this instrument to analyze samples of finished product that are not performing to spec. Mechanical problems that seem to be temperature related can be correlated to fundamental properties such as glass transition temperatures. For example, we found that the high temperature shear strength of our Masterweld 5970A/ 42B was related to the glass transition temperature. As a result, we were able to make very specific recommendations for the product – that it should only be used at certain grinding temperatures of 175ºF or less. For significantly higher temperatures, we would recommend a different material with a higher glass transition temperature and the associated high crosslinking density.
The dielectric analyzer (DEA) measures resistance to electrical current as well as the storage of an electrical charge in materials. The instrument functions by rapidly oscillating a charge difference between two parallel plates and measuring the time lag for the change to occur in the sample materials between the two plates. From this time lag, it is possible to determine the values of the material’s dielectric constant or energy storage from a material sample. The DEA can be operated at a constant temperature or frequency or across a broad range of temperatures and frequencies. A sample can be measured, cycled through temperature ranges and remeasured to test intended operating conditions. Alternately, a product can be measured, removed, exposed to temperature and humidity cycling, and remeasured to establish performance limits for a final product.
The DEA can be used for technical service when customers have problems with electronic potting materials. For example, one customer had difficulties with signal loss with a specific batch of potting material. The DEA was used to verify that the dielectric constant was high on the customer’s defective material, while showing normal properties on freshly mixed material. Based on this data and an abnormal DSC test, the customer’s meter-mix dispensing equipment was examined and the problem identified as an improper mix ratio, too high in curing agent. Materials testing is a critically important aspect of quality control, especially given the exacting tolerances of electrical materials. We invested in these instruments to pinpoint problems and lead the way to fast effective solutions. AA
For more information please contact Fielco at 215-674-8700 or visit our web site at http://www.fielco.corn.
AA REPRINTED FROM ADHESIVES AGE, JUNE 1998 | physics |
https://johnstonsarchive.net/relativity/binpulsar.html | 2023-06-01T14:55:44 | s3://commoncrawl/crawl-data/CC-MAIN-2023-23/segments/1685224647895.20/warc/CC-MAIN-20230601143134-20230601173134-00217.warc.gz | 0.663698 | 2,470 | CC-MAIN-2023-23 | webtext-fineweb__CC-MAIN-2023-23__0__191243368 | en | Binary pulsar PSR B1913+16
compiled by Wm. Robert Johnston
last updated 30 August 2004
The binary pulsar PSR B1913+16 (=J1915+1606) was discovered in the summer of 1974 by Russell A. Hulse (Univ. of Massachusetts/Amherst, later Princeton Univ.) and Joseph H. Taylor (Princeton Univ.). Also known as the Hulse-Taylor binary pulsar, it comprises two neutron stars closely orbiting their common center of mass. One of these neutron stars is detected as a pulsar.
The subsequent study of this binary has provided the strongest evidence to date for the existence of gravitational waves. General relativity predicts that such a system will radiate energy in the form of gravitational waves, causing the stars to slowly spiral towards each other. In 1982 Hulse and Taylor could report, after eight years of observation, that the system was losing energy and inspiralling at the rate predicted by Einstein's general relativity.
Data on the PSR B1913+16 system:
|Distance||21,000 light years|
|Mass of detected pulsar||1.441 MSun|
|Mass of companion||1.387 MSun|
|Rotational period of detected pulsar||59.02999792988 millisec|
|Diameter of each neutron star||20 km|
|Orbital period||7.751939106 hr|
|Semimajor axis||1,950,100 km|
|Periastron separation||746,600 km|
|Apastron separation||3,153,600 km|
|Orbital velocity of stars at periastron|
(relative to center of mass)
|Orbital velocity of stars at apastron|
(relative to center of mass)
|Rate of decrease of orbital period||0.0000765 sec per year|
|Rate of decrease of semimajor axis||3.5 meters per year|
|Calculated lifetime (to final inspiral)||300,000,000 years|
Here is a list of pulsars in binary systems.
Press release announcing awarding of 1993 Nobel prize in physics to Hulse and Taylor
Page on The binary pulsar PSR B1913+16 from Cornell University's ASTRO 201 course.
A little more technical: a list of abstracts from NASA's ADS regarding PSR B1913+16, including ArXiv preprints:
- Willems, B., Kalogera, V., & Henninger, M. 2004, ArXiv Astrophysics e-prints Pulsar Kicks and Spin Tilts in the Close Double Neutron Stars PSR J0737-3039, PSR B1534+12 and PSR B1913+16
- Esposito-Farese, Gilles 2004, ArXiv General Relativity and Quantum Cosmology e-prints Binary-pulsar tests of strong-field gravity and gravitational radiation damping
- Kazanas, Demosthenes & Teplitz, Vigdor L. 2004, Astrophysical Journal Competition Between Gravitational and Scalar Field Radiation
- Kazanas, Demosthenes & Teplitz, Vigdor 2003, ArXiv Astrophysics e-prints Competition Between Gravitational and Scalar Field Radiation
- Dewi, J. D. M. & Pols, O. R. 2003, Monthly Notices of the Royal Astronomical Society The late stages of evolution of helium star-neutron star binaries and the formation of double neutron star systems
- Colpi, M. & Wasserman, I. 2003, Pulsars, AXPs and SGRs Observed with BeppoSAX and Other Observatories Spin-perpendicular kicks from evanescent binaries formed in the aftermath of rotational core-collapse and the nature of the observed bimodal distribution of pulsar peculiar velocities
- Dewi, J. D. M. & Pols, O. R. 2003, ArXiv Astrophysics e-prints The late stages of evolution of helium star-neutron star binaries and the formation of double neutron star systems
- Konacki, Maciej, Wolszczan, Alex, & Stairs, Ingrid H. 2003, Astrophysical Journal Geodetic Precession and Timing of the Relativistic Binary Pulsars PSR B1534+12 and PSR B1913+16
- Kramer, M., Löhmer, O., & Karastergiou, A. 2003, ASP Conf. Ser. 302: Radio Pulsars Geodetic Precession in PSR B1913+16
- Weisberg, J. M. & Taylor, J. H. 2003, ASP Conf. Ser. 302: Radio Pulsars The Relativistic Binary Pulsar B1913+16
- Dewi, Jasinta & Pols, Onno 2003, IAU Symposium The Formation of Double Neutron Star Systems
- Kaper, Lex 2003, IAU Symposium Gamma-ray bursts: the most powerful cosmic explosions
- Weisberg, Joel M. & Taylor, Joseph H. 2002, Astrophysical Journal General Relativistic Geodetic Spin Precession in Binary Pulsar B1913+16: Mapping the Emission Beam in Two Dimensions
- Kim, C., Kalogera, V., & Lorimer, D. R. 2002, Bulletin of the American Astronomical Society Statistical Analysis of The Galactic Coalescence Rate of Neutron Star Binary Systems
- Finn, Lee Samuel & Sutton, Patrick J. 2002, Physical Review D Bounding the mass of the graviton using binary pulsar observations
- Francischelli, G. J., Wijers, R. A. M. J., & Brown, G. E. 2002, Astrophysical Journal The Evolution of Relativistic Binary Progenitor Systems
- Kalogera, V., Narayan, R., Spergel, D. N., & Taylor, J. H. 2001, Astrophysical Journal The Coalescence Rate of Double Neutron Star Systems
- Will, Clifford 2001, Living Reviews in Relativity The Confrontation between General Relativity and Experiment
- Kramer, M., Wex, N., Kalogera, V., & et al. 2001, IAU Symposium Asymmetric supernova explosion investigated by geodetic precession
- Weisberg, J. M. & Taylor, J. H. 2000, Bulletin of the American Astronomical Society Relativistic Precession in Binary Pulsar B1913+16: Mapping the Beam in Two Dimensions
- Wex, N., Kalogera, V., & Kramer, M. 2000, Astrophysical Journal Constraints on Supernova Kicks from the Double Neutron Star System PSR B1913+16
- Weisberg, Joel M. & Taylor, Joseph H. 2000, ASP Conf. Ser. 202: IAU Colloq. 177: Pulsar Astronomy - 2000 and Beyond General Relativistic Precession of the Spin Axis of Binary Pulsar B1913+16: First Two Dimensional Maps of the Emission Beam
- Karastergiou, A., Kramer, M., Wex, N., & von Hoensbroech, A. 2000, ASP Conf. Ser. 202: IAU Colloq. 177: Pulsar Astronomy - 2000 and Beyond Geodetic Precession and the Binary Pulsar B1913+16
- Arzoumanian, Z., Cordes, J. M., & Wasserman, I. 1999, Astrophysical Journal Pulsar Spin Evolution, Kinematics, and the Birthrate of Neutron Star Binaries
- Kramer, Michael 1998, Astrophysical Journal Determination of the Geometry of the PSR B1913+16 System by Geodetic Precession
- Nice, D. J. 1998, Bulletin of the American Astronomical Society Pulsar Timing Measurements of Gravitational Waves
- Bethe, Hans A. & Brown, G. E. 1998, Astrophysical Journal Evolution of Binary Compact Objects That Merge
- Kopeikin, Sergei M. 1997, Physical Review D Binary pulsars as detectors of ultralow-frequency gravitational waves
- van den Heuvel, E. P. J. & Lorimer, D. R. 1996, Monthly Notices of the Royal Astronomical Society On the galactic and cosmic merger rate of double neutron stars.
- Kopeikin, S. M. 1996, Astrophysical Journal Proper Motion of Binary Pulsars as a Source of Secular Variations of Orbital Parameters
- Lipunov, V. M. & Panchenko, I. E. 1996, Astronomy and Astrophysics Pulsars revived by gravitational waves.
- Mohanty, Subhendra & Panda, Prafulla Kumar 1996, Physical Review D Particle physics bounds from the Hulse-Taylor binary
- Curran, S. J. & Lorimer, D. R. 1995, Monthly Notices of the Royal Astronomical Society Pulsar Statistics - Part Three - Neutron Star Binaries
- Doroshenko, O. V. & Kopeikin, S. M. 1995, Monthly Notices of the Royal Astronomical Society Relativistic effect of gravitational deflection of light in binary pulsars
- Sivaram, C. 1995, Bulletin of the Astronomical Society of India The Hulse-Taylor binary pulsar PSR 1913+16.
- Fakir, Redouane 1994, Physical Review D Detectable time delays from gravity waves\?
- Camilo, F., Thorsett, S. E., & Kulkarni, S. R. 1994, Astrophysical Journal The magnetic fields, ages, and original spin periods of millisecond pulsars
- Sigurdsson, Steinn & Hernquist, Lars 1992, Astrophysical Journal A novel mechanism for creating double pulsars
- Damour, T. 1984, General Relativity and Gravitation Conference The motion of compact bodies and gravitational radiation
- Damour, T. 1983, Gravitational Radiation Gravitational radiation and the motion of compact bodies
- Caporali, A. 1979, Munich International Astronautical Federation Congress Relativistic celestial mechanics of extended bodies
- Kristian, J. & Westphal, J. A. 1978, Bulletin of the American Astronomical Society A Visible Candidate for the Hulse-Taylor Binary Pulsar
- Shao, C.-Y. & Liller, W. 1978, Astrophysical Journal Astrometry and photometry of stars in the vicinity of the Hulse-Taylor binary pulsar
- Hjellming, R. M. & Gibson, D. M. 1975, Astrophysical Journal An interferometric search for the Hulse-Taylor binary pulsar
- Esposito, L. W. & Harrison, E. R. 1975, Astrophysical Journal Properties of the Hulse-Taylor binary pulsar system
© 2001-2002, 2004 by Wm. Robert Johnston.
Last modified 30 August 2004.
Return to Home. Return to Gravitational waves. Return to Relativistic physics. Return to Astronomy and space. | physics |
http://ncrept.uark.edu/ | 2015-06-02T05:16:57 | s3://commoncrawl/crawl-data/CC-MAIN-2015-22/segments/1433195035356.2/warc/CC-MAIN-20150601214355-00033-ip-10-180-206-219.ec2.internal.warc.gz | 0.926976 | 117 | CC-MAIN-2015-22 | webtext-fineweb__CC-MAIN-2015-22__0__138282285 | en | Welcome to the University of Arkansas' National Center for Reliable Electric Power Transmission (NCREPT).
NCREPT was established for the purpose of investigating solid-state solutions for the electric power grid including protection devices and FACTS as well as energy storage and distributed generation applications. We are capable of testing distributed energy resources under IEEE 1547 and UL 1741 standards. For more information about testing at NCREPT, please contact Mr. T.A. Walton by email at [email protected] or by phone at 479-575-4487. | physics |
https://www.meteosim.com/en/siam-o-en/ | 2021-04-14T04:38:56 | s3://commoncrawl/crawl-data/CC-MAIN-2021-17/segments/1618038076819.36/warc/CC-MAIN-20210414034544-20210414064544-00063.warc.gz | 0.900614 | 207 | CC-MAIN-2021-17 | webtext-fineweb__CC-MAIN-2021-17__0__246689040 | en | The use of SIAM-O enables you to locate and predict the potential occurrence of unpleasant odours by means of meteorological simulation and dispersion systems. It can be used either by public authorities with odour problems, or by industries (waste management, chemical industry, etc.) whose activity may lead to the occurrence of unpleasant odours.
Its main features are:
- Trajectory Calculations – provide information on the path which a particular gas causing unpleasant odours emitted by a known source will take.
- Back-tracking Calculations – provide information on the origin of the mass of air that has affected a specific point in the past in order to determine its origin.
- Odour Dispersion Forecasting – provides information about how a certain substance causing unpleasant odours will be dispersed in the atmosphere in the coming days.
Among the tool’s different features, we can highlight the email alerts, with unpleasant odour limit exceedance alerts and warnings of possible weather hazards that may affect a particular activity. | physics |
https://www.energyplus.ca/en/mysafety/farmsafety.asp | 2017-04-23T21:46:02 | s3://commoncrawl/crawl-data/CC-MAIN-2017-17/segments/1492917118831.16/warc/CC-MAIN-20170423031158-00351-ip-10-145-167-34.ec2.internal.warc.gz | 0.923897 | 350 | CC-MAIN-2017-17 | webtext-fineweb__CC-MAIN-2017-17__0__144851258 | en | Some farms have overhead power lines crossing their property. You don't have to touch a power line to be electrocuted. Even coming close can cause the electricity to jump between the wire and material that conducts electricity, such as farm equipment, ladders, tree limbs and even hay, under certain conditions.
See the Electrical Safety Authority's Farm Safety Tips.
Call Before You Dig
Electrical and othe dangerous hazards are lurking everywhere underground. Never assume you know the location or depth of a cable, wire or pipe. Be smart, be safe and contact Ontario One Call to request a FREE underground electrical locate on your property.
Varying amounts of low-level voltage often exists between the earth and electrically-grounded farm equipment, such as metal stabling, feeders, or milk pipelines. The voltage that causes this small current is known as "animal contact voltage", "stray voltage" or "tingle voltage". Usually, these voltage levels present no harm, however, at high enough levels, these stray voltage may impact the health and behaviour of livestock.
Fact Sheet - About Stray Voltage (.pdf) Text-only Fact Sheet (.pdf)
More information about Stray Voltage can be found on the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) website.
If you think you have a stray voltage problem affecting your livestock, or if you have any questions or concerns about the electrical service on your property, please submit a Farm Stray Voltage Reporting form, or contact our Customer Care Team.
* Please note that this form will be received during regular office hours, from 8:30 a.m. to 4:30 pm, Monday through Friday, statutory holidays not included. | physics |
https://www.heatcon.com/product/hc150240m51x-clearance-heat-blanket/ | 2024-02-22T17:28:04 | s3://commoncrawl/crawl-data/CC-MAIN-2024-10/segments/1707947473824.13/warc/CC-MAIN-20240222161802-20240222191802-00392.warc.gz | 0.769253 | 250 | CC-MAIN-2024-10 | webtext-fineweb__CC-MAIN-2024-10__0__56924179 | en | HC150240M51X – Clearance Heat Blanket
15in X 24in (38.1cm x 60.96cm) FLIGHT-LINE, 120V, 1800 WATTS
W/ GROUND PLAIN SUPERVISORY CIRCUIT
15ft (4.572m) LEADS
**Care Instructions for HEATCON® Silicone Rubber Heaters Included**
Our clearance heat blankets are readily available for your composite repair needs. HEATCON silicone rubber heat blankets are specifically designed for the repair of composite structures using vacuum bagging techniques. The unique construction of our heat blankets allows you to apply uniform heat exactly where you want it. Our design employs a grid of resistance wire and fiberglass reinforced silicone rubber that provides strength, flexibility, and even heat distribution.
To learn how we test our heat blankets, visit: https://www.heatcon.com/services/heat-blanket-testing/
Please contact us for Price. Thank you.
To learn how we test our heat blankets, visit our <a href=”https://www.heatcon.com/services/heat-blanket-testing/”>Heat Blanket Testing</a> page. | physics |
https://roham-chat.ir/%E2%80%8Eintroduction-to-planetary-photometry-rendered-into-persian/ | 2022-12-04T01:46:43 | s3://commoncrawl/crawl-data/CC-MAIN-2022-49/segments/1669446710953.78/warc/CC-MAIN-20221204004054-20221204034054-00627.warc.gz | 0.899764 | 327 | CC-MAIN-2022-49 | webtext-fineweb__CC-MAIN-2022-49__0__184611926 | en | Originally printed by Cambridge University Press in 2017, the book has been translated by an Iranian university instructor Arsia Moghtaderi (PhD) and released by Vasef Lahiji Publishing in 1000 copies.
Introducing planetary photometry as a quantitative remote sensing tool, this handbook demonstrates how reflected light can be measured and used to investigate the physical properties of bodies in our Solar System.
The author explains how data gathered from telescopes and spacecraft are processed and used to infer properties such as the size, shape, albedo, and composition of celestial objects including planets, moons, asteroids, and comets.
‘Introduction to Planetary Photometry’ begins with an overview of the history and background theory of photometry, later chapters delve into the physical principles behind commonly used photometric models and the mechanics of observation, data reduction, and analysis.
Real-world examples, problems, and case studies are included, all at an introductory level suitable for new graduate students, planetary scientists, amateur astronomers and researchers looking for an overview of this field.
Michael K. Shepard is Professor of Geosciences at Bloomsburg University of Pennsylvania, specialising in remote sensing, planetary photometry and asteroid studies. He is the author of the popular science book ‘Asteroids: Relics of Ancient Time’ (Cambridge, 2015), articles for popular science magazines like ‘Sky’ and ‘Telescope’, and a guest science column for the regional ‘Press Enterprise’ newspaper. | physics |
https://www.tvvsound.eu/product-page/yt5021 | 2021-06-15T01:12:46 | s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623487614006.8/warc/CC-MAIN-20210614232115-20210615022115-00068.warc.gz | 0.93121 | 257 | CC-MAIN-2021-25 | webtext-fineweb__CC-MAIN-2021-25__0__115380988 | en | Beyerdynamic’s PREMIUM microphone head with cardioid recording pattern as a directed head is designed for recordings in environments with various noise levels. Thus, it can be called an all-purpose answer for reporters. Because of its sound pickup from the front, it filters background noise and ensures crystal clear recordings through excellent and natural frequency response. The cardioid pickup pattern suits best for interviews in various surroundings like events and outdoor locations with a lot of traffic noise. Using the head, there is no common proximity effect of directed microphones due to the high-pass-filter that is found inside the iXm recorder’s LEA Engine. LEA achieves a perfect balance of frequency ranges.
As an electret microphone head, this microphone head is created to capture smallest sound pressure levels. Thus, its recording pattern is more sensitive in higher frequency ranges which results in a higher resolved pattern in the end zone compared to a dynamic microphone head.
- Electret condenser mic capsule
- Superb natural frequency response
- Shock-mount isolation protects your recording from handheld noise
- Sensitivity: 6mV/Pa +/- 4dB
- Impedance: 200 Ohm
- Dimensions: 71mm x Ø 50mm
- Weight: 138g | physics |
https://www.twoth.com/blog-dental-implants-zinc-and-strontium-based-phosphate-glass-beads-a-novel-material-for-bone-tissue-engineering/ | 2024-03-03T18:52:50 | s3://commoncrawl/crawl-data/CC-MAIN-2024-10/segments/1707947476397.24/warc/CC-MAIN-20240303174631-20240303204631-00853.warc.gz | 0.904447 | 487 | CC-MAIN-2024-10 | webtext-fineweb__CC-MAIN-2024-10__0__196602064 | en | In the quest for innovative materials in the field of osteoconductive substances, degradable phosphate-based glasses incorporating strontium, zinc, and calcium have taken center stage. This investigation delves into the intricate world of glass beads, exploring their composition under the general formula of (P2O5)-(Na2O)-(TiO2)-(CaO)-(SrO) or (ZnO). Prepared through a meticulous melt quench technique, followed by milling and spheroidization, these glass beads hold the promise of reshaping the landscape of materials used in hard tissue engineering.
The journey begins with the meticulous crafting of glass beads, laying the foundation for their potential as osteoconductive materials. X-ray diffraction unveils the intricate structure of these degradable phosphate-based glasses. Size distribution is meticulously evaluated through scanning electron microscopy (SEM), offering insights into the morphology that sets the stage for subsequent studies.
The investigation proceeds with immersing select glass bead samples in deionized water, unraveling surface changes and measuring ion release rates. pH variations are scrutinized as another crucial aspect of their functionality. The results not only shed light on the dynamic nature of these materials but also pave the way for understanding their potential applications in the biological milieu.
A pivotal phase of the exploration unfolds as human osteoblast-like osteosarcoma cells MG63 and human mesenchymal stem cells become the focus. The glass beads host a series of assays, including the CCK assay, ALP assay, and Ca assay, to gauge their cytocompatibility. SEM images and fluorescence images from confocal microscopy further enrich the understanding of cellular interactions, presenting a comprehensive view of the biocompatibility of these innovative materials.
In conclusion, the degradable phosphate-based glasses investigated in this study, enriched with strontium and zinc, showcase a promising trajectory as osteoconductive materials. The intricate interplay of structure, size, ion release, and pH dynamics highlights their dynamic nature. Cellular studies affirm their enhanced cellular proliferation, suggesting a potential application in hard tissue engineering. Notably, glass beads with 5 mol% zinc content and 17.5 mol% strontium content emerge as particularly promising candidates, paving the way for further exploration and potential breakthroughs in the realm of innovative biomaterials. | physics |
https://www.physx.u-szeged.hu/oktatas/kepzeseink/international-physics | 2023-09-27T14:56:40 | s3://commoncrawl/crawl-data/CC-MAIN-2023-40/segments/1695233510300.41/warc/CC-MAIN-20230927135227-20230927165227-00289.warc.gz | 0.89907 | 364 | CC-MAIN-2023-40 | webtext-fineweb__CC-MAIN-2023-40__0__183007500 | en | Title of the programme: International Physics MSc (LASCALA)
Degree: MSc in Physics, Specialized in Large Scale Facilities in Accelerators and Lasers (LASCALA)
Duration of the course: 4 semesters
Language of tuition: English
Description of the programme:
The LASCALA master aims at training experts in the most advanced experimental and theoretical tools and concepts in accelerators, high power lasers and associated advanced sources, as well as in their applications for science and society. The LASCALA master is coordinated by Paris-Saclay University (France), with Lund University (Sweden), La Sapienza University Rome (Italy) and the University of Szeged (Hungary) as partners. The students will be ready to develop innovative ideas and enterprises related to large scale facilities.
The programme includes classes, tutorials, project- and research-based trainings. Students will take advantage of seminars by international speakers, up-to-date technology demonstrations, as well as visits and practices on large scale facilities (e.g. Synchrotron SOLEIL, Pettawatt laser APOLLON, Proton Therapy Centre of Orsay, Lund Laser Centre, MaxIV synchrotron, ELI Beamlines laser facility, SPARC particle accelerator, FLAME multiterrawatt laser, CERN, ITER Tokamak, Laser Mégajoule (LMJ), etc.)
An intensive summer school also fosters the students' entrepreneurial skills including economy management, communication, patent law, and technology transfer courses so they can face the job market.
For further details, tuition fees, scholarships and course application see: https://master-lascala.eu/about-us/general-description | physics |
https://ecco-v4-python-tutorial.readthedocs.io/fields.html | 2022-12-03T09:10:05 | s3://commoncrawl/crawl-data/CC-MAIN-2022-49/segments/1669446710926.23/warc/CC-MAIN-20221203075717-20221203105717-00554.warc.gz | 0.769068 | 910 | CC-MAIN-2022-49 | webtext-fineweb__CC-MAIN-2022-49__0__292827965 | en | ECCO v4 state estimate ocean, sea-ice, and atmosphere fields¶
The complete state estimate consists of a set of ocean, sea-ice, air-sea flux, and atmosphere state variables that are the output from a free-running ocean and sea-ice general circulation model.
Ocean, sea-ice, air-sea flux, and atmosphere fields are provided in two spatial layouts:
- 13-tile native lat-lon-cap 90 (llc90) grid
- 0.5° x 0.5° latitude and longitude grid
13-tile native lat-lon-cap 90 grid¶
The lat-lon-cap (llc) is the decomposition of the spherical Earth into a Cartesian curvilinear coordinate system . It is a topologically non-trivial cubed-sphere rendering in the northern hemisphere and a dipolar grid in the southern hemisphere. Between 70°S and ~57°N, model grid cells are approximately oriented to lines of latitude and longitude. A special Arctic “cap” is situated north of ~57°N.
The Cartesian curvilinear coordinate system is divided into 13 tiles, each consisting of 90x90 grid cells in the horizontal and 50 vertical levels. Horizontal model grid resolution varies spatially from 22km to 110km, with the highest resolutions at high latitudes and lowest resolution in mid latitudes. Vertical grid spacing increases with depth from 10m to 456.5m. The bottom of the deepest model grid cell is 6145m below the surface.
The Cartesian (x,y) coordinates of llc tiles do not coorespond to longitude and latitude. Horizontal velocities are defined relative to the local orientation of x and y in the tile. Velocities in the positive x direction are defined as positive u. Velocities in the positive y direction are defined as positive v.
Available fields on the llc90 grid¶
monthly-averaged ocean and sea-ice fields: https://ecco.jpl.nasa.gov/drive/files/Version4/Release3/nctiles_monthly/README
monthly-snapshot ocean and sea-ice fields: https://ecco.jpl.nasa.gov/drive/files/Version4/Release3/nctiles_monthly_snapshots/README
daily-averaged ocean and sea-ice fields: https://ecco.jpl.nasa.gov/drive/files/Version4/Release3/nctiles_daily/README
6-hourly atmosphere fields: https://ecco.jpl.nasa.gov/drive/files/Version4/Release3/input_forcing/README
interpolated 0.5° x 0.5° latitude-longitude grid¶
Select monthly-average fields from the native lat-lon-cap model output have been interpolated to a more user-friendly 0.5° latitude-longitude grid.
Available fields on the 0.5° x 0.5° latitude-longitude grid¶
0.5° x 0.5° monthly-averaged ocean, sea-ice, and atmosphere fields: https://ecco.jpl.nasa.gov/drive/files/Version4/Release3/interp_monthly/README
Temporal frequency of state estimate fields¶
All three-dimensional ocean, sea-ice, and air-sea flux fields are provided as monthly averages. Select two-dimensional ocean and sea-ice fields are provided as daily averages. Atmospheric state fields are provided as 6-hourly records. In addition, potential temperature (theta), salinity, and free surface height anomaly at the ocean/sea-ice interface (etan) are provided as monthly snapshots to support budget closure calculations.
Because the state estimate fields are the output from a free-running ocean model, users can re-run the model to generate custom output on the native lat-lon-cap model grid. Instructions for doing so are provided here: https://ecco.jpl.nasa.gov/drive/files/Version4/Release3/doc/v4r3_reproduction_howto.pdf | physics |
https://kpfvt.com/en/sintering-advanced-ceramics-membranes-for-safe-solid-state-batteries-in-just-10-seconds/ | 2023-12-09T17:42:41 | s3://commoncrawl/crawl-data/CC-MAIN-2023-50/segments/1700679100942.92/warc/CC-MAIN-20231209170619-20231209200619-00396.warc.gz | 0.890809 | 425 | CC-MAIN-2023-50 | webtext-fineweb__CC-MAIN-2023-50__0__33091270 | en | The development of modern materials such as high-performance ceramics often relies on computational predictions as a valuable tool in accelerating the discovery process. It is essential to experimentally confirm the material properties of such predictions
“Unfortunately, the screening rates of predicted materials are limited by the long processing times and poor compositional control from volatile element loss in conventional ceramic sintering techniques,” Liangbing Hu, the Minta Martin Professor in the Department of Materials Science and Engineering at the University of Maryland, tells Nanowerk. “For instance, during our solid state battery research, we encountered the massive challenge posed by conventional sintering methods on fabricating solid state electrolytes due to the prolonged sintering process, severe volatile element loss, high porosity, and poor composition integration.”
He points out that the poor property of the solid state electrolytes (SSEs) results in the inferior electrochemical performance of the battery. To overcome these limitations, Hu’s team developed an ultrafast high-temperature sintering (UHS) technique to fabricate SSEs with dense structure and excellent electrochemical performance.
To conduct the process, the researchers sandwich a pressed green pellet of ceramic precursor powders between two Joule-heating carbon strips that rapidly heat the pellet through radiation and conduction to form a uniform high-temperature environment for quick synthesis (solid-state reaction) and reactive sintering. In an inert atmosphere, these carbon heating elements can provide a temperature of up to 3000 °C, which is sufficient to synthesize and sinter virtually any ceramic material. Comparing their new synthesis method with key parameters of conventional rapid sintering methods, the UHS technique has a much higher heating rate and cooling rate; requires much less sintering time (1–10 seconds); can reach a temperature of up to 3000 °C, and features minimal sample requirements, making it a general sintering method. Additionally, the UHS technique enables the realization of 3D printing structures and co-sintering of multilayer structures | physics |
https://epsci.ucr.edu/news/2022/01/11/how-webb-telescope-could-ultimately-help-protect-earth | 2023-09-25T22:53:18 | s3://commoncrawl/crawl-data/CC-MAIN-2023-40/segments/1695233510100.47/warc/CC-MAIN-20230925215547-20230926005547-00403.warc.gz | 0.920813 | 149 | CC-MAIN-2023-40 | webtext-fineweb__CC-MAIN-2023-40__0__18422745 | en | The James Webb Space Telescope, the most complex and expensive space laboratory ever created, is less than two weeks away from its ultimate destination a million miles from Earth. Once it arrives, it will send information about parts of space and time never seen before. It will also send previously unattainable information about parts of our own solar system.
UC Riverside astrophysicist Stephen Kane’s group will be using the telescope to look for planets like Venus in other parts of the galaxy. In addition to work with the Webb mission, Kane is also joining NASA on missions to Venus expected to launch after 2028. Here, he breaks down some unique aspects of the Webb, explains how the separate Venus projects intersect, and how both might benefit Earth. | physics |
https://zlat-ski.ru/radioactive-dating-lab-pennies-39646.html | 2020-08-05T01:27:06 | s3://commoncrawl/crawl-data/CC-MAIN-2020-34/segments/1596439735906.77/warc/CC-MAIN-20200805010001-20200805040001-00385.warc.gz | 0.943606 | 277 | CC-MAIN-2020-34 | webtext-fineweb__CC-MAIN-2020-34__0__10238432 | en | Radioactive dating lab pennies
" After introducing some of the concepts involved in radioactive decay, I do the demonstration. Tell them that they will be flipping the penny (you will tell them when); each time they flip one half life will have passed.
I usually let them keep the penny at the end of the class. If their penny lands on heads, they are radioactive and have decayed and they should sit; if their penny lands on tails, they have not decayed and may remain standing.
Students should begin to see the pattern that each time they “take a half-life,” about half of the surrogate radioactive material becomes stable.
Students then should be able to see the connection between the M&M’s and Puzzle Pieces and radioactive elements in archaeological samples.
The piles graphically show the meaning of the term “half-life.” Toss all the pennies onto a table surface.
The chance that any penny will come up tails on any toss is always the same, 50 percent.
However, once a penny has come up tails, it is removed.
The demonstration usually takes approximately 5-10 minutes depending on how long it takes to count the students.
If your class is particularly large, you might want to have a few students help you count the "undecayed" isotopes. | physics |
https://davies391.bookflyingcars.com/2021/03/18/what-is-a-bokeh-battery.html | 2021-06-15T00:02:50 | s3://commoncrawl/crawl-data/CC-MAIN-2021-25/segments/1623487614006.8/warc/CC-MAIN-20210614232115-20210615022115-00312.warc.gz | 0.940751 | 877 | CC-MAIN-2021-25 | webtext-fineweb__CC-MAIN-2021-25__0__128716971 | en | What is a Bokeh Battery?
BGo batteries have an electrochemical characteristic of charging and discharging. There are six common styles of BGo battery, each having its own distinctive features. The manufacturer’s specifications regarding the size and shape of the cell may vary slightly from model to model. However, all the BGo cells are standard in size and shape. The term ‘battery’ is used to describe any pair of batteries consisting of a cell and an outlet.
Bismuth borate or perhaps bistatic but is definitely an alkaline inorganic substance of bifrontal, bromine and oxygen. Commonly the term is usually used to describe the electrolyte-rich compound getting static crystalline construction, employed as a gentle thermally activated ionic conductor in battery pack anode designs. When a current is applied, the ions bonding to typically the negatively charged substrate are encapsulated inside the boat, which then releases typically the charge. Bistatic boron nitride batteries are known for high discharge costs and energy densities.
Boron nitride is created when the compound boron combines with oxides, resulting in the alteration of the boron in order to nitride. The producing product includes a gaseous form which is insoluble in water. It is mainly utilised in the manufacture of Nivea electric batteries, particularly Nivea Nitecore lithium batteries. In contrast to borate, bide, oxide is inert to be able to most chemical reactions; as a result it acts as a control and preventative for that effect between the electrodes and the cell. Thus, the o2 can prevent the cell components, which include the dishes and cells, through being prematurely subjected to harmful chemicals.
Bacterial copper mineral oxide is utilized in numerous types associated with batteries, in particular those possessing active chemical elements. This makes it an effective electrolyte. This type of battery produces less sulphation than borate rendering it suitable for make use of in mobile applications and industrial motorisation systems. Furthermore, copper mineral oxide can help sustain the performance of the battery while the particular sulphate-free compounds produce a setting that is usually less safe for that battery, such as when exposed to be able to fire.
Nitride boron battery electrodes also provide their particular uses. These electrodes are combined with carbon dioxide to form nitride clusters. Like co2, this produces a gas that is not inert. However , unlike carbon, which in turn causes a chemical effect that releases free radicals, when the particular electrodes come into contact with a great oxidising agent, nitride forms a gas that is inert. Nitroglycerin is the common compound applied in the manufacturing of nitride-based batteries.
Nitride-based batteries tend to be prepared by combining borate and lithium. Because the borate-lithium combos dissipate in the electrolyte, their interaction creates hydrogen. The producing product is called monohydrate and provides great potentiality for being a good director of electricity. Regrettably, the performance regarding these types associated with batteries is affected from the tendency regarding the active materials to bind along with the electrolyte resulting in a loss within voltage and the reduction in battery lifestyle. To remedy this, the battery might be subject to a few charge process before reaching complete performance levels once again.
On the other 모나코 카지노 palm, boron bide is a combination of boron and water piping oxide. Unlike nitroglycerin, this kind of battery really does not form a gas, but instead a solid crystalline form of oxide. It will not bind with the electrolytes. Instead, the oxide absorbs the energy through the active cations and releases it when the battery’s discharge time has the exact input voltage.
The supply of boron compounds ensures that bide electric batteries can be used to replace many of the active chemical-based batteries in your vehicle. Although these people are not as effective as nitroglycerin-based tissues, these are cheaper in addition to do not have the same harmful effects. Boron also improves the general efficiency of the battery. You may expect greater mileage from your vehicle and also longer lasting, safer battery overall performance. | physics |
http://raffleshistorynotes.weebly.com/the-copernican-revolution.html | 2017-04-30T05:00:01 | s3://commoncrawl/crawl-data/CC-MAIN-2017-17/segments/1492917124299.47/warc/CC-MAIN-20170423031204-00014-ip-10-145-167-34.ec2.internal.warc.gz | 0.932267 | 1,519 | CC-MAIN-2017-17 | webtext-fineweb__CC-MAIN-2017-17__0__94543580 | en | The Copernican Revolution - Copernicus, Kepler and Galileo
- Copernicus was influenced by Renaissance Platonism and ancient Greek texts
- The mathematical complexity of the Aristotelian-Ptolemaic system troubled Copernicus, who believed that truth was the product of elegance and simplicity.
- He set out on a life-long task to work out mathematical explanations of how a heliocentric universe operated.
- Because he did not want to engage in controversy with the followers of Aristotle, Copernicus did not publish his findings until 1543, in a work entitled On the Revolutions of the Heavenly Spheres.
- The helio-centric view of the universe was a very influential book in history, even more than the Origin of Species by Charles Darwin because it literally made the humans to rethink and challenge their place in the universe. (e.g. If we were not the centre, doesn’t that mean we are not special & is the Bible credible/is it telling us the truth?)
- Copernicus’ treatise on the universe retained some element of Aristotelian-Ptolemaic system.
- Copernicus never doubted Aristotle’s basic notion of perfect circular motion of the planets or the existence of crystalline spheres within which the stars revolved, and he retained many of Ptolemy’s epicycles. Thus, some of his mathematical proofs were wrong and rejected.
- But Copernicus proposed a heliocentric model of the universe that was mathematically simpler than Ptolemy’s earth-centred universe.
- Thus, he eliminated some of Ptolemy’s epicycles and cleared up various problems that had troubled astronomers who had based their work on an earth-centred universe.
- By removing the earth from its central position and by giving it motion - that is, by making the earth just another planet - Copernicus undermined the system of medieval cosmology and made the birth of modern astronomy possible. Because they were committed to the Aristotelian-Ptolemaic system and to biblical statements that supported it, most thinkers rejected Copernicus’ conclusions.
- Significance: Started the Scientific Revolution with the publication of On the Revolutions of Heavenly Spheres
Johannes Kepler (1571 - 1630)
- Kepler searched persistently for harmonious laws and planetary motion by making careful observations of the planetary objects.
- He did so because he believed profoundly in the Platonic ideal: a spiritual force infuses the physical order; beneath appearances are harmony and unity; and the human mind can begin to comprehend that unity only through gnosis - a direct and mystical realisation of unity - and through mathematics.
- Kepler believed that both approaches (Copernicus and Ptolemaic) were compatible, and he managed to combine them.
- He believed in and practiced in astrology, and throughout his lifetime he tried to contact an ancient but lost and secret wisdom.
- Kepler discovered three basic laws of planetary motions.
- First, the orbits of the planets are elliptical, not circular as Aristotle and Ptolemy had assumed & the sun is one focus of the ellipse.
- Kepler’s second law demonstrated that the velocity of a planet is not uniform, as had been believed, but increases as its distance from the sun decreases.
- Kepler’s third law - that the squares of the times taken by any two planets in their revolutions around the sun are in the same ratio as the cubes of their average distances from the sun - brought the planets together into a unified mathematical system.
- Kepler gave the mathematical proof to Copernicus’ theory
- eliminated forever the use of epicycles
- demonstrated that mathematical relationships can describe the planetary system
Galileo Galilei (1564 - 1642)
- Believed that beyond the visible world lay universal truths, subject to mathematical verification (influence of Renaissance Platonism)
- Also believed that only after experimenting can one discern the harmonious laws of the universe and give them mathematical expression - he was an adamant supporter of empiricism and his unwavering spirit of empiricism inspired many generations of scientists. Hence, it is arguable who (Copernicus or Galileo) was mainly responsible for the start of the Scientific Revolution.
- established a fundamental principle of modern science - the order of uniformity of nature
- invented the telescope
- discovered that the Moon is not smooth, uniform and precisely spherical; it is uneven, rough and full of crevices [from his The Starry Messenger].
- discovered the Sun has sunspots
- The discovery about the Moon and the Sun challenged the conventional view that heavenly bodies (e.g. stars, planets) stay the same throughout. The heavenly bodies do go through changes just like the earthly bodies. Hence, there are no higher and lower worlds; nature is the same throughout.
- also discovered the moons orbiting around Jupiter (aka Galilean moons: Io, Europa, Ganymede and Callisto) → supported the Copernican heliocentric theory: If Jupiter had moons, then all heavenly bodies did not orbit the earth.
- Galileo was oppressed by the Catholic Church who viewed his discovery as a threat to their position rather than accepting his discovery as true science.
- NOTE: The Starry Messenger mostly described the astronomical discoveries Galileo made using his telescope. It was the Dialogue Concerning the Two Chief World Systems [Geocentrism and Heliocentrism] that got Galileo in trouble with the Church. In it, he supported the Copernican view of the universe. The Dialogue was placed on the Index of Forbidden Books and banned by the Catholic Church for corrupting the minds of the people and challenging the biblical records of the movement of the Sun around the Earth.
By the middle of the seventeenth century, largely due to the work of Copernicus, Kepler and
Galileo, Aristotle and Ptolemy had been dethroned. People began to accept the heliocentric theory of the universe and abandoned the geocentric view of the universe. People took the philosophy of science in which nature, especially physical laws and motion, can be explained mathematically. However, what was missing was an overriding law that could explain the motion observed in the heavens and on earth. This law was supplied by Issac Newton (culmination of the Scientific Revolution).
http://www.historyguide.org/earlymod/lecture10c.html (Lecture 10: The Scientific Revolution, 1543 - 1600)
http://www.historyguide.org/earlymod/lecture11c.html (Lecture 11: The Scientific Revolution, 1600 - 1642)
http://www.historyguide.org/earlymod/lecture12c.html (Lecture 12: The Scientific Revolution, 1642 - 1730)
http://law2.umkc.edu/faculty/projects/ftrials/galileo/galileo.html (Trial of Galileo)
http://en.wikipedia.org/wiki/Dialogue_Concerning_the_Two_Chief_World_Systems (Dialogue Concerning the Two Chief World Systems) | physics |
http://reserved.ego-gw.it/public/vesf/vesf.aspx | 2021-03-08T00:24:09 | s3://commoncrawl/crawl-data/CC-MAIN-2021-10/segments/1614178381230.99/warc/CC-MAIN-20210307231028-20210308021028-00004.warc.gz | 0.892096 | 281 | CC-MAIN-2021-10 | webtext-fineweb__CC-MAIN-2021-10__0__135590264 | en | Collaboration and the CNRS
EGO Consortium have set-up a Forum where participating astrophysicists and theorists contribute to the further development of scientific knowledge around Virgo.
It is the purpose of the Virgo–EGO Scientific Forum (VESF
) to enlarge the research community around the present Virgo collaboration by providing individual participants and institutions interested with scientific opportunities of stimulating research, publications, and all other scientific activities.
includes the members of the Virgo Collaboration and scientists interested in gravitational wave research from other laboratories, observatories and institutions.
scope, functions and organization are detailed in its Charter
As foreseen in the Charter, the VESF governing body is its Council.
The Council elects the members of the Executive Board which, in turn, appoints the VESF Coordinator.
The Executive Board (EB) is currently formed by:
Among the VESF core activities are the funding of fellowships and the organization of schools on gravitational waves.
- The call for 2015 VESF Prizes is now open
New deadline: 2015 November 15.
For information on VESF, please contact the EGO Scientific Secretariat:
Tel: +39 050 752325
Postal address: via E. Amaldi
56021 S. Stefano a Macerata - Cascina (PI) | physics |
https://genesagarden.wordpress.com/2012/03/23/how-is-a-dome-energy-efficient/ | 2018-10-17T21:45:05 | s3://commoncrawl/crawl-data/CC-MAIN-2018-43/segments/1539583511216.45/warc/CC-MAIN-20181017195553-20181017221053-00354.warc.gz | 0.928264 | 152 | CC-MAIN-2018-43 | webtext-fineweb__CC-MAIN-2018-43__0__3613307 | en | The net annual energy savings for a dome owner is 30% less than normal rectilinear homes according to the Oregon Dome Co. This is quite an improvement and helps save the environment from wasted energy.
The decreased surface area of a geodesic dome requires less building materials, which means that there is less surface area per unit of volume per spherical structure; exposure to cold in the winter and heat in the summer is decreased. The concave interior creates a natural airflow that allows the hot or cool air to flow evenly throughout the dome with the help of return air ducts. Extreme wind turbulence is lessened because winds that contribute to heat loss flow smoothly around the dome. And with the proper heating or cooling equipment, the internal temperature can be controlled. | physics |
http://www.mercateo.ie/p/163IE-6272223/Measuring_instrument_for_viscosity_analysis_ViscoClock_plus_Type_ViscoClock_plus_M1_115_V.html | 2023-09-24T07:42:10 | s3://commoncrawl/crawl-data/CC-MAIN-2023-40/segments/1695233506623.27/warc/CC-MAIN-20230924055210-20230924085210-00164.warc.gz | 0.806442 | 470 | CC-MAIN-2023-40 | webtext-fineweb__CC-MAIN-2023-40__0__279725587 | en | Measuring instrument for viscosity analysis ViscoClock plus
The ViscoCIock plus is an electronic timing unit for glass capillary viscometers used to determine kinematic and relative viscosity. Succeeding the well-proven ViscoCIock, the new instrument features data storage and simpler handling. The ViscoCIock plus is designed for SI AnalyticsUbbelohde (DIN; ASTM; Micro) and Micro Ostwald viscometers. To determine absolute kinematic viscosities, viscometers have to be used which are calibrated for automatic measurements. The ViscoClock plus automatically measures the flow time of temperature-stabilized liquids in capillary viscometers by means of infrared light barriers. The viscometer including a sample is inserted into the ViscoClock plus and immersed into a thermostatic bath for temperature stabilization. After thermostating, the sample is pumped into the measuring bulb, and the flow time is detected automatically. The large display enables easy read-off of flow times and additional information: date, time, sample ID and viscometer ID.
The ViscoClock plus can be used in all SI Analytics bath types.
ViscoClock plus: Electronic timing unit for glass capillary viscometers, power supply 100-230 V, manual pump
ViscoClock plus M1: Device incl. thermostatic bath for temperatures from 10 to 60 °C
ViscoClock plus M2: Device incl. thermostatic bath for temperatures from -40 to 150 °C
Measuring range: Up to 999.99 secs. / resolution 0.01 sec.
Timing accuracy: ±0.01 sec. ±1 digit
Measuring range viscosity: 0.35 to 10000 mm2/sec. (cSt)
USB interface: For connecting an USB stick or a printer (TZ 3863)
Operating temperature: Stand: -40 to +150 °C
Electronic measuring unit: +10 to +40 °C
Dimensions (W x D x H): approx. 90 x 30 x 515 mm
Weight: approx. 450 g (without viscometer)
Power pack approx. 220 g
Type ViscoClock plus M1, 115 V | physics |
https://rangiattcollege.in/national-science-day-celebration-on-28-02-2023/ | 2024-04-17T16:05:36 | s3://commoncrawl/crawl-data/CC-MAIN-2024-18/segments/1712296817158.8/warc/CC-MAIN-20240417142102-20240417172102-00403.warc.gz | 0.946932 | 333 | CC-MAIN-2024-18 | webtext-fineweb__CC-MAIN-2024-18__0__40485357 | en | It is with great pleasure that I extend a cordial invitation to you on behalf of the Principal and staff of Rangia Teacher Training College. We would be honored if you could attend the National Science Day celebration, which will take place on February 28th, 2023, at 9:30 AM.
The event will be held at Rangia Teacher Training College, and we are excited to announce that Dr. Monoj Kumar Singha, Associate Professor of the Department of Physics at Rangia College, will be joining us as our esteemed Chief Guest. Additionally, we are pleased to welcome Purushottam Sinha, Principal of Kendriya Vidyalaya, Rangia, as our distinguished Guest of Honour.
As you may know, National Science Day is an important occasion that celebrates the contributions of Indian scientists in the field of science and technology. This day is observed every year to commemorate the discovery of the Raman effect by Sir C. V. Raman, who was the first Indian to receive the Nobel Prize in Physics. The event will be a wonderful opportunity to recognize and celebrate the achievements of Indian scientists and their contributions to society.
We believe that your presence and participation in the celebration will be highly valuable and greatly appreciated. Your contribution to the discussion on the importance of science in our society will be a valuable addition to the event.
Thank you for your consideration, and we look forward to seeing you at the National Science Day celebration.
Organized by, the Dept. of Science, Rangia Teacher Training College
Date: 28.02.2023 (09:30 am onwards) | physics |
https://localpractice.wordpress.com/2014/11/09/throwing-water-down-the-drain-simple-steps-for-heat-recovery/ | 2018-07-21T15:23:18 | s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676592636.68/warc/CC-MAIN-20180721145209-20180721165209-00419.warc.gz | 0.950443 | 646 | CC-MAIN-2018-30 | webtext-fineweb__CC-MAIN-2018-30__0__275970695 | en | Throwing Water Down the Drain: Simple Steps for Heat Recovery
Many of us turn a few knobs and, miraculously, hot water comes out without much thought other than our energy and water bills. However, the water that ends up in the drain retains a certain about of embodied energy that is capable of being recovered. This water is now technically graywater, but you’ve paid valuable money for the energy used to raise its temperature. It makes sense to recapture this energy and there are a few great products that can help with this.
Heat recovery is nothing new, however it is becoming more main stream and affordable than ever before. If you’re looking to cut a few bucks out of your energy bill while looking for a relatively easy way to help make a bigger impact on your regional energy footprint, then a small addition to your water circulation lines may be the answer.
Large-scale buildings implement large-scale heat recovery units which are mechanical systems that extract the remaining heat energy from already heated water once it’s past through a building’s heating system. When applied at this scale, this strategy can provide tremendous savings. While larger buildings consume an overwhelming proportion of energy, a growing population means increased demands at both global and regional levels. Achieving our energy independence goals will require infrastructural change at the federal level, however, we as home owners can make a significant contribution to this effort by adjusting a few priorities without breaking the bank.
Showers, bath tubs, and sinks are a prime example of wasted heat energy. For example, showers use water stored in a hot water tank that is typically heated by natural gas, oil or electricity to a high temperature of 77° F. This may not seem that hot, but this can be 20-30 degrees warmer than the water coming into your building from the city supply. This water is then rinsed over the body at 13 – 21 gallons per minute (10 minute shower = 210 gallons!), depending on the fixture (which can be as low as 1.25 gallons per minute) and enters directly into the drain. This heat energy should be headed back to your hot water heater rather than out to the street’s waste water line.
Below is a diagram of a typical hot water loop. Notice the potential for transferring hot water energy from fixtures into the cold water supply line before it enters the hot water heater.
A company called Ecodrain has created a sleek apparatus that can be installed to do just this. Heated graywater transfers it’s heat energy to fresh potable water as one leaves the system and the other enters. The two streams never actually mix and only heat energy is transferred. This raises the temperature of potable water as it enters the house so the hot water tank uses less energy to raise the temperature. These systems are now available for residential use and claim to have a short-term payback of only a few years.
Have you installed a similar system in your home? Have you noticed any savings? Comment below and let us know if heat recovery is making a difference in your life, or if you think it’s a complete waste. | physics |
http://standrewsenergy.org/index.php?option=com_content&view=article&id=68&Itemid=62 | 2013-12-05T17:04:59 | s3://commoncrawl/crawl-data/CC-MAIN-2013-48/segments/1386163046950/warc/CC-MAIN-20131204131726-00092-ip-10-33-133-15.ec2.internal.warc.gz | 0.974862 | 129 | CC-MAIN-2013-48 | webtext-fineweb__CC-MAIN-2013-48__0__6512448 | en | The STANDEN team are combatting the loss of heat from radiators positioned on external walls. Many homes have benefitted from the installation of radiator panels which are fitted behind their radiators, reflecting the heat back into the room and not into the cold wall.
The panels are very effective and do not cost a lot. In some cases they are free but for those able to pay it is an inexpensive addition to your home to keep the heat you pay for within your home.
Due to the popularity of these panels the StAndEN team have appointed volunteers to help with fitting them. The picture shows a delighted Stephen Jones receiving his panels. | physics |
https://topytools.com/power-converter | 2023-09-22T15:08:54 | s3://commoncrawl/crawl-data/CC-MAIN-2023-40/segments/1695233506420.84/warc/CC-MAIN-20230922134342-20230922164342-00639.warc.gz | 0.881314 | 762 | CC-MAIN-2023-40 | webtext-fineweb__CC-MAIN-2023-40__0__109940071 | en | Our Power Converter is a convenient online tool for converting power units like watts, volts, amps, and much more. Simplify power conversions for electrical engineers, students, and hobbyists with this free tool.
Share on Social Media:
Introducing Power Converter Tool: Simplifying Power Unit Conversion
In today's technologically advanced world, the need for power unit conversions arises more often than not. Whether you're tackling electrical projects or in need of precise power measurements, TopyTools has you covered with its innovative Power Converter tool. It ensures convenience and reliability for all your power-related needs. This article will delve into the remarkable capabilities and advantages of this tool, highlighting how it effortlessly simplifies power conversion tasks.
Effortless Power Unit Conversion Made Easy
Designed with a user-friendly interface, TopyTools Power Converter tool is your go-to solution for streamlining power unit conversions. With just a few clicks, you can swiftly input a value in one unit and convert it to another. This versatile tool supports a wide range of power units, including watts, kilowatts, horsepower, and more, catering to different applications.
Accurate and Reliable Results You Can Trust
Precision is key when it comes to power conversion, and TopyTools Power Converter tool ensures accurate and dependable results every time. Its sophisticated algorithms guarantee precise conversions without any loss of precision or rounding errors. With unwavering confidence in the generated answers, you can move forward with power-related calculations or tasks without hesitation.
Flexible Unit Conversion at Your Fingertips
Power Converter tool offers unparalleled flexibility by allowing seamless conversions in both directions. No matter if you want to convert from watts to kilowatts or the other way around, this versatile tool is here to meet your specific needs. Furthermore, it supports conversion between multiple power measurement systems, accommodating both metric and imperial units. This versatility ensures effortless power unit conversion, tailored to your preferred method of measurement.
Save Time and Boost Productivity
Manually converting power units can be a real hassle, taking up valuable time and leaving room for pesky errors to sneak in. With the Power Converter tool from TopyTools, the need for manual calculations becomes a thing of the past. Its user-friendly interface and instant results empower you to swiftly obtain the converted power value, saving you valuable time and effort. This time-saving feature allows you to focus on other important tasks, thus enhancing overall productivity.
Discover the Power of TopyTools Power Converter Tool
Experience the convenience and efficiency of TopyTools Power Converter tool for yourself. Say goodbye to cumbersome manual calculations and hello to effortless power unit conversion at your fingertips. Unlock the true potential of accurate power conversions with this remarkable tool.
Convenient for Professionals and DIY Enthusiasts:
TopyTools' Power Converter tool is a versatile solution that caters to the needs of professionals and DIY enthusiasts alike. Whether you're an electrician, engineer, or technician, this tool offers precise power unit conversion capabilities to enhance your calculations and designs. But that's not all - even if you're an amateur or a DIY enthusiast, the Power Converter tool can still be your go-to for various projects and experiments. With its user-friendly interface, accurate results, flexibility in unit conversion, and time-saving features, it's an indispensable asset.
In conclusion, the Power Converter tool from TopyTools simplifies power unit conversions and ensures precise measurements. With its engaging structure, this equipment becomes the ultimate solution for all your power conversion needs. Experience the seamless power conversion and witness the operational efficiency as you streamline your tasks with our innovative Power Converter tool. | physics |
https://producenewmedia.com/pulldown | 2023-10-02T19:14:39 | s3://commoncrawl/crawl-data/CC-MAIN-2023-40/segments/1695233511002.91/warc/CC-MAIN-20231002164819-20231002194819-00859.warc.gz | 0.879782 | 285 | CC-MAIN-2023-40 | webtext-fineweb__CC-MAIN-2023-40__0__135884819 | en | Confused by the term Pulldown, or Telecine?
Here are the facts:
24p = 23.98 fps (Progressive)
29.97 fps = 59.94 interlaced fields per second, aka 60i
• Interlaced video displays 60 half frames per second
• Progressive video takes entire video frames on the go
• Progressive video requires 2x the bandwidth of interlaced video
This is the conversion process: 24p (film or video) — 29.97 (video).
• 2:3, or 3:2 (aka 2:3:2:3): 60 fields / 24 = 2.5. So each frame of 24p material needs to last for 2.5 frames of video
• 2:3:3:2 is referred to as Advanced Pulldown
Here’s how it works: we are transferring 24p to 60i, which means we are converting 24 frames per second into 60 fields per second. The first frame of film is transferred to the first two fields of video and the next frame of film is transferred to the next three fields – 2:3. This results in some frames of film spanning two different frames of video or, to put it another way, some frames of video that are composed of fields from two different frames of film. | physics |
https://physics-quiz-approach.en.aptoide.com/?store_name=apps&app_id=31104234 | 2019-09-22T12:14:07 | s3://commoncrawl/crawl-data/CC-MAIN-2019-39/segments/1568514575513.97/warc/CC-MAIN-20190922114839-20190922140839-00334.warc.gz | 0.882074 | 258 | CC-MAIN-2019-39 | webtext-fineweb__CC-MAIN-2019-39__0__68897082 | en | Download this app to your desktop
Physics MCQs app
Here is an easy way to self-evaluate your Physics Knowledge. A simple quiz app that improves your knowledge in Physics and helps you in self-evaluating as well learn basics and advanced Physics- through Multiple Choice questions.
- Beautiful UI
- Review your answers against correct answers instantly
- Review anytime, anywhere
- Tons of Multiple Choice questions (MCQs) ! Have fun and same time learn.
- Select the number of questions you want to answer.
- You wont face same questions every time. Questions are randomized every time you take a test.
- Explanations given to answers.
-Tons of topics will be added progressively. The questions will auto sync into the app. No need to update
Circular Motion, Current Electricity, Electromagnetic Waves, Electronic Devices, Electrostatics, Gravitation, Kinetic Theory of Gases, Laws of Motion, Matter and Radiation, Oscillations, Physical World and Measurement, Radiation, Rotational Motion, Stationary Waves, Surface Tension, Thermodynamics, Wave Motion, Work, Energy and Power.
Excellent resource for preparing school exams, college exams as well for any competitive exams , NEET etc. | physics |
https://sc.bennetts.co.uk/bikesocial/news-and-views/features/bikes/how-do-hydraulic-brakes-work | 2021-05-18T01:14:17 | s3://commoncrawl/crawl-data/CC-MAIN-2021-21/segments/1620243991650.73/warc/CC-MAIN-20210518002309-20210518032309-00624.warc.gz | 0.936073 | 1,319 | CC-MAIN-2021-21 | webtext-fineweb__CC-MAIN-2021-21__0__110719490 | en | How can one finger exert this much stopping power? By the cunning force multiplication that takes place in your braking system…
If you’ve ever experienced brake fade or, god forbid, brake failure, you’ll have an appreciation of just how important it is that brakes work consistently. Here are the basic principles and components for modern brakes – and by that we mean hydraulic ones, with discs not drums.
Modern motorcycle brakes work by transferring movement and force at the lever through an incompressible liquid to the caliper pistons, which then press the brake pads against the disc. For that force to be transferred efficiently, the brake lines must not expand, there must be no leaks and the fluid must not compress. If any of those happen, you get spongey-feeling brakes, or indeed no brakes. Gulp.
The brake lever operates a piston, which operates as a plunger in what’s called the master cylinder. Both are housed in the casting that holds the brake lever. A master cylinder piston is pretty small - around 10-20mm in diameter. The pistons at the other end, in the calipers, are much bigger – around 25-50mm. Why the different sizes? That leads us to…
The first way that forces are amplified are at the lever itself. This is purely mechanical – if your fingers are 10cm from the pivot point, and the master cylinder piston is 2cm the other side, then forces will be magnified 5 times, but there will be five times less movement. Then there’s amplification due to piston sizes. The smaller the master cylinder piston, the more pressure it will apply to the system for a given force at the lever. If that sounds counter-intuitive, imagine your foot being trodden on by someone wearing a stiletto heel. It’ll be a lot more painful than if they’re wearing a broad shoe. The pressure in the system is then transferred to the caliper pistons, and the force they generate depends on the ratio of the areas of the piston faces. So let’s say the master cylinder piston has a diameter of 15mm, meaning its area is 177mm squared. Our caliper piston has a diameter of 25mm, giving a surface area of 1964mm squared. So the force is multiplied 11 times. Combine that with the lever, and in this case you’re magnifying the force 55 times. And that’s just with one caliper piston. On a modern front end there are usually four pistons in each caliper, and there are two of those. That gives a 440 times force multiplication in our example. No wonder you can use two fingers to make the bike stand on its nose.
A smaller master cylinder piston will apply more pressure and create more braking force but it will move less fluid, so the lever will have to move further to move the caliper pistons enough make the pads grip the discs. That means there is a limit to how small you can go with master cylinder pistons, and how big the caliper pistons can be. Also, big caliper pistons mean you need big discs (check out a cruiser rear brake), which are heavy.
Many modern four-piston calipers have two smaller pistons. This is to increase feel. The smaller pistons will move further than the larger ones and therefore push the brake pad before the others join in.
Radial brakes have the caliper bolts directed at the wheel spindle
There have been two main caliper innovations in the last couple of decades. Radial calipers (named because they are attached by bolts which radiate from the wheel centre, rather than laterally from a mounting bracket) are stiffer and perform better under extreme conditions, such as racing. For 99% of us, they make no difference. Monoblock calipers, as the name suggest, are made from one lump of metal, rather than two bolted together. This eradicates the tiny amount of flex between the two halves of a normal caliper and in theory gives better feel. Again, most of us can’t ride hard enough to notice the difference.
Once you’ve got forces arriving at the caliper pistons, it’s then over to the brake pads. These have to convert the kinetic energy of you and the bike into heat by rubbing against the discs. This is some task – if you’re shifting, there’s a hell of a lot of energy, which means a lot of heat.
Non-radial brakes are attached to a bracket. Unless you’re racing, they’re just as good as radials
For most modern bikes, you’ll want HH pads, which have the highest coefficient of friction – both at normal temperatures (the first H) and at 350C (the second). Then it’s a case of choosing the material, and how it’s made. Organic pads are nothing of the sort – it just means there is no metal in them. They are cheap, gentle on discs, don’t last as long and fade if you hammer them. Not the best choice for sportsbikes. Semi-metallic pads contain some metal, and have a higher friction coefficient than organics and better fade characteristics. Then there are sintered pads. These have a high coefficient of friction and good heat transfer. They’re more expensive and can be hard on discs, but are the ones to have if you’ve got a powerful bike.
Brake fluid is easily forgotten, as it just sits there transfering brake forces from lever to pads. The problem is that brake fluid can degrade, potentially allowing your brakes to fade under hard use. For motorcycles there are three types: DOT 3, 4 and 5.1 (forget DOT 5 – it’s not recommended for bikes). The numbers refer to boiling points and viscosity. Generally, the higher the DOT number, the better the fluid – it will be lower viscosity and have a higher boiling point (this is important because you don’t want the fluid boiling, and becoming compressible, when your brake pads get hot). The problem with all these fluids is they absorb water from air, which lowers their boiling point. That’s why you should change your brake fluid every two years and make sure any brake fluid bottles are tightly sealed. | physics |
https://www.geckomaterials.com/specifications | 2023-12-09T08:51:17 | s3://commoncrawl/crawl-data/CC-MAIN-2023-50/segments/1700679100873.6/warc/CC-MAIN-20231209071722-20231209101722-00142.warc.gz | 0.799617 | 256 | CC-MAIN-2023-50 | webtext-fineweb__CC-MAIN-2023-50__0__16358793 | en | geCKo Materials' is a cost-effective, energy-saving Dry Adhesive inspired by nature. It has microwedges that grip the surface when a shear force is applied—just like a gecko climbing a wall. The attachment of the microwedges is purely mechanical and does not involve suction or chemical interactions. These microwedges attach and detach in milliseconds and can be reused 120,000 times without performance loss. And unlike other adhesives, the detachment is instant, leaves no residue and does not require energy.
How it Works
Inspired by nature, our dry adhesive’s micro wedges mimic the gecko's foot structure to create their signature grip.
Made for Innovation, geCKo Materials is strong yet simple to use. It enables powerful gripping without the hassle or mess of traditional solutions.
Inside a Stanford lab, our CEO unlocked mass manufacturing and the scalability of geCKo Materials’ adhesive. The method is IP and trade secret protected.
Can hold ～120 kPa in shear stress
Functional for a range of applications
Requires zero force to attach/detach
Leaves no residue or marring
Engages in milliseconds
Can be reused up to 120,000 times | physics |
https://propartsusa.com/products/1810d0350-hypercoil-556 | 2024-04-20T04:55:23 | s3://commoncrawl/crawl-data/CC-MAIN-2024-18/segments/1712296817474.31/warc/CC-MAIN-20240420025340-20240420055340-00056.warc.gz | 0.895527 | 398 | CC-MAIN-2024-18 | webtext-fineweb__CC-MAIN-2024-18__0__185922844 | en | Hyperco's neverending pursuit of Performance has lead to yet another breakthrough in Conventional Motorsports spring design -- the "Dynamic Travel Response" enhancement!
Our engineers analyzed the dynamic characteristics that are essential to Conventional Spring performance and utilized this data to develop the Dynamic Travel Response design concept. Our conventional springs are engineered to exceed the dynamic performance requirements for travel and rate linearity placed on them in the race car. Another result of the DTR concept is a significant reduction in the physical weight of each spring. As spring travel and total load requirements are part of the Dynamic Travel design criteria, Hyperco was able to reduce the weight and improve the performance of our entire Conventional Spring line without compromising consistency and durability.
The results are in...Hyperco's Dynamic Travel Response enhancement is a winner at every level (dirt & pavement).
Optimum Body DiameterOptimum Body Diameter (OBD) Hypercoils feature a unique design concept that adjusts the body diameter of the spring relative to the end coils. The OBD design enables Hyperco to take full advantage of its ultra-high tensile material by optimizing the applied stress through adjusting the spring's body diameter.
The results are in and they are simply incredible:
Increased Rate Linearity
More Resistance to Bowing
Fits All Standard Hardware
Maintains Free Length
Ultra High TravelUltra High Travel (UHT) Hypercoils are designed specifically for light rate / high travel coil-over applications (dirt & pavement). UHT designs meet the requirements of soft spring / big bar set ups and remain consistent in free length & installed height. The new UHT design features a larger "body bulge" over our standard OBD designs, allowing for additional deflection, rate linearity and resistance to bowing.
Currently available in 12", 14", 15" & 16" free lengths with 2.5" inner diameter. | physics |
https://man-health-magazine-online.com/male-sexual-health/male-infertility/spermbot-could-help-solve-male-infertility-headline-science/ | 2021-10-27T03:53:41 | s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323588053.38/warc/CC-MAIN-20211027022823-20211027052823-00377.warc.gz | 0.868464 | 183 | CC-MAIN-2021-43 | webtext-fineweb__CC-MAIN-2021-43__0__124155238 | en | One of the main causes of infertility is low sperm motility. Sperm that are healthy, but can’t swim. Now a team of scientists has developed a possible solution: the Spermbot.
Oliver Schmidt, Ph.D. and his team at the IFW in Dresden, Germany built a tiny metal helix controlled by a rotating magnetic field. The Spermbot can wrap around a sperm and drive it into an egg, leading to possible fertilization.
The research appears in the ACS journal Nano Letters.
Original article: http://pubs.acs.org/doi/abs/10.1021/acs.nanolett.5b04221
ACS Nano Letters: http://pubs.acs.org/journal/nalefd
ACS Headline Science:
Oliver Schmidt, Ph.D. – IFW Dresden | physics |
http://www.everite.com/capabilities/burr-free-cutting-machining/what-is-electrochemical-grinding/ | 2013-05-24T12:55:15 | s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368704658856/warc/CC-MAIN-20130516114418-00000-ip-10-60-113-184.ec2.internal.warc.gz | 0.905668 | 605 | CC-MAIN-2013-20 | webtext-fineweb__CC-MAIN-2013-20__0__125268483 | en | Scientific and metallurgical developments have placed unusual demands on the metalworking industry. The challenges faced by industry are not only modern materials with high strength-to-weight ratios, but also with new fabrication requirements demanding greater precision and surface integrity.
Electrochemical Grinding Equipment (ECG) is an ideal machining process that provides a better, faster, and more cost effective metal cutting and grinding solution for today’s toughest materials. Unlike conventional grinding techniques, Electrochemical Grinding offers the ability to machine difficult materials independent of their hardness or strength. This is because Electrochemical Grinding is an entirely different machining process in which electrical energy combines with chemical energy for metal removal. Since Electrochemical Grinding Equipment does not rely solely on an abrasive process, the results are precise cuts free of heat, stress, burrs and mechanical distortions.
Electrochemical oxidation and reduction occurs on the surface of electrodes when an electric current is passed between the electrodes through an electrolyte fluid. An electrochemical potential between the electrodes causes current to flow from the anode to the cathode in the DC circuit. In Electrochemical Grinding, the anode is the work piece, and the cathode is the conductive grinding wheel. A continuous stream of electrolyte flows at the interface of the grinding wheel and work piece and conducts the current in the circuit. The electrolyte fluid is a conductive aqueous solution consisting of a mixture of chemical salts and other additives. At the positive electrode, or anode, oxidation of the work piece dissolves the surface of the metal and forms a metal oxide film. The film is electrically insulating, and acts as a barrier against the electrochemical cutting action of the process
The abrasives in the rotating grinding wheel continually remove this film and expose a fresh surface for oxidation. Metal deposition on the grinding wheel (cathode) is avoided by proper choice of electrolyte. Dissolution of the metal, combined with the mechanical removal of the oxides, results in an efficient low-stress cut.
According to Faraday’s Laws the quantity of chemical change occurring at an electrode is directly proportional to the amount of current passing between the electrodes. Low voltage, high current electrical energy supplied by a properly designed DC power supply is central to the Electrochemical Grinding process. Since the voltages are low, spark discharge and the associated heat are avoided. In addition, the low voltages used prevent any electrical shock hazard to the operator.
With Electrochemical Grinding, the rate of metal removal is directly proportional to the current flowing across the contact surface between the wheel (cathode) and work piece (anode). The higher the amperage, the faster the rate of chemical change and stock removal. “Machinability” of a metal depends more upon its conductivity and electrochemical reactivity than its hardness or strength. Electrochemical Grinding Equipment can be used successfully on all electrochemically reactive and conductive materials. | physics |
http://drcharukohli.in/services/dental-x-ray/ | 2019-02-22T12:08:47 | s3://commoncrawl/crawl-data/CC-MAIN-2019-09/segments/1550247517815.83/warc/CC-MAIN-20190222114817-20190222140817-00449.warc.gz | 0.926582 | 384 | CC-MAIN-2019-09 | webtext-fineweb__CC-MAIN-2019-09__0__97510181 | en | Dental X-rays are a type of image of the teeth and mouth. X-rays are a form of high energy electromagnetic radiation. X-rays can penetrate the body to form an image on film.
Structures that are dense (such as silver fillings or metal restoration) will block most of the light energy from the x-ray. They will appear white on developed film. Structures containing air will be black on film, and teeth, tissue, and fluid will appear as shades of gray.
How the Test is Performed
The test is performed in the dentist’s office. There are many types of dental X-rays. Some are:
Palatal (also called occlusal)
The bitewing shows the crown portions of the top and bottom teeth together when the patient bites on a paper tab.
The periapical shows one or two complete teeth from crown to root.
A palatal or occlusal X-ray captures all the upper and lower teeth in one shot while the film rests on the biting surface of the teeth.
A panoramic X-ray requires a special machine that rotates around the head. The X-ray captures the entire jaws and teeth in one shot. It is used to plan treatment for dental implants, check for impacted wisdom teeth, and detect jaw problems. A panoramic X-ray is not the best method for detecting cavities, unless the decay is very advanced and deep.
In addition, many dentists are taking X-rays using digital technology. The image runs through a computer. The amount of radiation given off during the procedure is less than traditional methods. Other types of dental X-rays can create a 3-D picture of the jaw. Cone beam computerized tomography (CBCT) may be used prior to dental surgery, especially when multiple implants are being placed. | physics |
https://uusatrg.utah.edu/RBSMITH/public_html/students.html | 2023-12-02T11:55:18 | s3://commoncrawl/crawl-data/CC-MAIN-2023-50/segments/1700679100399.81/warc/CC-MAIN-20231202105028-20231202135028-00389.warc.gz | 0.680999 | 2,073 | CC-MAIN-2023-50 | webtext-fineweb__CC-MAIN-2023-50__0__48151944 | en | University of Utah
An Interdisciplinary Academic Program in Earth Science
|Graduate Students of Bob Smith|
|Ph.D Students Masters Students|
|Ph.D. Students Supervised|
Stanley, W. D., 1971, An Integrated Geophysical Study Related to Ground Water with Conditions of Cache Valley Utah and Idaho
Mikulich, M. J., 1971, Seismic Reflection and Aeromagnetic Surveys of the Great Salt Lake, Utah
Braile, L., 1972, Seismic Interpretation of Crustal Structure across the Wasatch Front with Applications of Geophysical Data Inversion
Otis, R. M., 1975, Interpretation and Digital Processing of Seismic Reflection and Refraction Data from Yellowstone Lake, Wyoming.
Pelton, J., 1978, The Analysis of Deformation-Induced Variations in Orthometric Height and Gravity with Application to Recent Crustal Movements in Yellowstone National Park
Doser, D. I., 1984, Source Parameters and Faulting Processes of the August 1959 Hebgen Lake, Montana Earthquake Sequence
Benz, H. M., 1986, Synthetic Seismograms for the Elastic Wave Case: Finite-Difference Forward and Inverse Modeling.
Michaels, P. M., 1993, Surface Wave Inversion by Neural Networks.
Lowry, Anthony L., 1994, Flexural Strength, Stress, and Effective Elastic Thickness of the Western U. S. Cordillera.
John O. D. Byrd, 1995, Neotectonics of the Teton fault, Wyoming.
Waite, G., 2003, Teleseismic tomography and anisotropy imaging of the Yellowstone Hotspot.
Chang, W. L., 2004, GPS studies of the Wasatch fault zone, Utah, with implications for elastic and viscoelastic fault behavior and earthquake hazard.
|M.S. Students Supervised|
Beck, P., 1970, The Southern Nevada-Utah Border Earthquakes, August to December, 1966
Winkler, P. L., 1972, Source Mechanisms of Earthquakes Associated with Coal Mines in Eastern Utah
Trimble, A. B., 1973, Seismicity and Contemporary Tectonics of the Yellowstone Park-Hebgen Lake Region
Freidline, R. A., 1974, Seismicity and Contemporary Tectonics of the Helena, Montana Area
Hendrajaya, L., 1975, Theoretical Estimation of Hydrocarbon Reservoir Pressure Using Seismic Wave Velocity
Bailey, J. P., 1976, Seismicity and Contemporary Tectonics of the Hebgen Lake-Centennial Valley, Montana Area
Gronseth, K. A., 1976, Seismic Velocities of an In- Situ, Jointed Block Under Controlled Stress Conditions
Wong, I. G., 1976, Site Amplification of Seismic Shear Waves in Salt Lake Valley, Utah
Heaney, R. J., 1976, Frequency-Wave Number Velocity Filters and Their Application to Seismic Data
Estill, R. E., 1976, Temporal Variations of P-Wave Travel Times and Lateral Velocity Variations across the Wasatch Front
Olsen, T.L., 1976, Earthquake Surveys of the Roosevelt Hot Springs and the Cove Fort Areas, Utah.
Gaiser, J., 1977, Origin Corrected Travel-Time Variations measured across the Wasatch Front
Kastrinsky, A., 1977, Seismicity of the Wasatch Front, Utah: Detailed Epicenter Patterns and Anomalous Activity
Evoy, J., 1978, Precision Gravity Reobservations and Simultaneous Inversion of Gravity and Seismic Data for Subsurface Structure of Yellowstone
Gertson, R. C., 1979, Interpretation of a Seismic Refraction Profile across the Roosevelt Hot Springs, Utah and Vicinity
Schilly, M. M., 1979, Interpretation of Crustal Seismic Refraction and Reflection Profiles from Yellowstone and the Eastern Snake River Plain
Hawley, B. W., 1979, Simultaneous Inversion of Local Earthquake Data for Hypocenters and Laterally Varying Velocity Structure
Wechsler, D. J., 1979, An Evaluation of Hypocenter Location Techniques with Applications to Southern Utah: Regional Earthquake Distributions and Seismicity of Geothermal Areas
Lehman, J. 1980, Upper-Crustal Structure Beneath Yellowstone National Park from Seismic Refraction and Gravity Observations
Doser, D. I., 1980, Earthquake Recurrence Rates from Seismic Moment Rates in Utah
Owens, T. J, 1980, Flexure and Normal Faulting in Lithospheric Plates with Application to the Wasatch Front, Utah
Clawson, S., 1981, The Lateral Inverse Q- structure of the Upper Crust in Yellowstone National Park from Seismic Refraction Data.
Benz, H. M., 1982, Simultaneous Inversion for Lateral Velocity Variations and Hypocenters in the Yellowstone Region Using Earthquake and Controlled Sources
Bashore, W. M., 1982, Upper Crustal Structure of the Salt Lake Valley and the Wasatch Fault from Seismic Modeling.
Smith, K. A., 1984, Thesis: Normal Faulting in an Extensional Domain: Constraints From Seismic Reflection Interpretation and Modeling
Brokaw, M. , 1985, Two-Dimensional Seismic Velocity Models of the Yellowstone Caldera
DeSisto, J., 1985, Comparison of Synthetic Seismograms
Gants, D. G., 1985, Geologic and Mechanical Properties of the Sevier Desert Detachment as Inferred by Seismic and Rheologic Modeling
Barker, C. A., 1986, Upper-Crustal Structure of the Milford Valley and Roosevelt Hot Springs, Utah, Region by Modeling of Seismic Refraction and Reflection Data.
Eddington, P. K., 1986, Lithospheric Strain Rates and Deformation Models of Great Basin Extension
Viveiros, J. J., 1986, Cenozoic Tectonics of the Great Salt Lake From Seismic Reflection Data.
Leu, L. L., 1986, Three-Dimensional Velocity Structure of the 1983 M7.3, Borah Peak, Idaho, Earthquake Area Using Tomographic Inversion of Aftershock Travel-Times
Planke, S., 1987, Cenozoic Structures and Evolution of the Sevier Desert Basin, West-Central Utah, From Seismic Reflection Data
Chen, G. J., 1988, A Study of Seismicity and Spectral Source Characteristics of Small Earthquakes: Hansel Valley, Utah and Pocatello Valley, Idaho Areas.
Kjos, E.J., 1988, The Feasibility of Imaging Near-Vertical Incidence Lower Crustal and Upper Mantle Reflections from Seismic Refraction Data.
Matulevich, M.R.M., 1988, Extremal Inversion of Seismic Reflection Data for the 1986 PASSCAL Basin and Range Seismic Experiment.
Braun, J., 1989, Two-Dimensional Traveltime Inversion for Crustal Structure Using Refraction Data from the 1986 PASSCAL Basin-Range Seismic Experiment
Peyton, S. L., 1991, Contemporary Tectonics of the Yellowstone-Hebgen Lake Region From Earthquake Focal Mechanisms and Stress Field Inversion, 90p.
Stephenson, W. J., 1991, High-Resolution Seismic Imaging and Gravity Analysis of Deformation Across the Wasatch Fault, Kaysville, Utah, 86p.
McNeil, B. R., 1991, Upper Crustal Structure of the Northern Wasatch Front, Utah, From Seismic Reflection and Gravity Data, 63p.
Mason, D. B., 1992, Earthquake magnitude potential of active faults in the Intermountain seismic Belt from surface parameter scaling, 110p.
Miller, D. S., 1994, Three-dimensional P and S velocity structureof the Yellowstone Plateau from local earthquake and controlled source tomography.
Martinez, L. J., 1996, Global Positioning System measurements of the crustal deformation and strain of the Wasatch fault zone, Utah.
Kikkert, D. W., 1996, Lg attenuation in northern California.
Chang, W. L., 1998, Earthquake hazards on the Wasatch fault from tectonic induced flooding and stress triggering of earthquakes, 123 pp.
Lynch, D., 1999, Three-dimensional P-wave inversion of the crust and upper mantle structure from the Basin and Range to the Colorado Plateau-Rocky Mountains using earthquake and controlled source data, 155 pp.
Waite, Gregory, 1999, Seismicity of the Yellowstone Plateau: Space-Time Patterns and Stresses From Focal Mechanism Inversion, 191 pp.
Braun, J., 1999, Earthquake displacement hazard of the Wasatch and surrounding faults, Wasatch Front, Utah. (Environmental Engineering Degree jointly chaired with Ron Bruhn)
Puskas, C., 2000, Deformation of the Yellowstone caldera, Hebgen Lake fault zone, and eastern Snake River Plain from GPS, seismicity and moment release.
Krukoski, J., 2002, Density models of the Yellowstone magmatic system from gravity field inversion and a prototype GeoGIS system for Yellowstone, M.S. Thesis, University of Utah.
White, B. P., 2005, Seismicity,seismotectonics and preliminary earthquake hazard analysis of the Teton region, Wyoming.
Farrell, J. M., 2007, Space-time seismicity and development of a geographical information system database withinteractive graphics for the Yellowstone region. | physics |
http://www.w24.co.za/Entertainment/Technology/Born-to-be-wired-20091012-2 | 2017-10-20T23:19:48 | s3://commoncrawl/crawl-data/CC-MAIN-2017-43/segments/1508187824471.6/warc/CC-MAIN-20171020230225-20171021010225-00757.warc.gz | 0.958593 | 835 | CC-MAIN-2017-43 | webtext-fineweb__CC-MAIN-2017-43__0__139387503 | en | Born to be wired
Remember what it was like, a dozen years or so ago, when you tried to communicate with someone on the other side of the world? The truncated conversations down crackly copper wires? The chore of sending papers or pictures by post -- by "snail mail"? The insane costs of long-distance contact of almost any kind?
It's no surprise why we have embraced digital technology with such passion, why we have leapt to Internet and email without even a backward glance. Today, letters, documents and images are dispatched instantly, flawlessly and for free to a recipient thousands of kilometres (miles) away, and phone calls cost just a tiny fraction of what they did in the past.
Physicists Charles Kao, Willard Boyle and George Smith won the Nobel Prize on Tuesday for their part in what many see as a revolution of the mind, changing perspectives about geography and human relationships, as much as it is a revolution of technology.
Kao won half the prize for realising the potential of optical fibres, whose cables now girdle the Earth on the sea floor and across land, delivering data by laser pulse through glass strands.
Boyle and Smith shared a quarter each of the coveted prize for inventing the charge-coupled device (CCD), a semiconductor sensor that converts light into electrical signals, in 1969.
It became the "electronic eye" of the digital camera, used not only by happy-snapping holidaymakers, but also by doctors to get images inside the human body for microsurgery, and by space probes, to get pictures of Saturn and other planets.
"It's taken 30 years [for Nobel recognition], but the importance of these two technologies is obvious," said Phillip Schewe of the American Institute of Physics.
"Ours is the age of information and images, and no two things better symbolise this than the Internet and digital cameras," said Robert Kirby-Harris, chief executive at the Institute of Physics (IOP) in London.
"From kilobytes to gigabytes, and now to petabytes and exabytes, information has never been so free-flowing or, with the development of CCD, so instantly visual.
"These incredible inventors who have been responsible for transforming the world in which we live very much deserve their prize."
The idea of using glass tubes to transmit information dates back to the 1920, with experiments to send images through thin fibres.
But the outcome was disappointing. Whenever the tubes touched, or their surface was scratched, the light "leaked" away.
In 1966, Kao, a young Shanghai-born engineer working at the Standard Telecommunication Laboratories (STL) in Harlow, near London, determined that the main problem lay with iron ions in the glass, which absorbed and scattered the light.
His solution was fused silica, a glass-making process that would be without the impurities.
The difficulty, though, was that fused silica has a highly melting point, and it was tough to make and manipulate such materials on a commercial scale.
Four years afterward, the technical breakthrough came at Corning Glass Works in the United States.
Optical fibre was born, and has been continuously improved since then, thanks to chemical "doping" in the manufacturing process to help mitigate light loss.
Today, a pulse sent down a modern optical fibre loses less than five percent of its light after one kilometre (five-eighths of a mile).
The first transatlantic fibre-optic was installed in 1988, but the real bounty of this technology started to be realised in the late Nineties, when cheap lasers, light repeaters and computing power to handle large packets of data became available.
Kao was "a revolutionary," said Sir Peter Knight, senior principal at Imperial College London.
"He had already spotted the communications opportunities, and therefore the great distances light could travel, while others were still thinking in metres (yards)."
How has technology improved your lifestyle? Let us know in the box below... | physics |
http://prod.lsa.umich.edu/umbs/news-events/all-news/archived-news/2010/09/buoy-now-streaming-data-from-douglas-lake.html | 2023-02-01T21:39:17 | s3://commoncrawl/crawl-data/CC-MAIN-2023-06/segments/1674764499953.47/warc/CC-MAIN-20230201211725-20230202001725-00842.warc.gz | 0.905841 | 212 | CC-MAIN-2023-06 | webtext-fineweb__CC-MAIN-2023-06__0__32485763 | en | A team that included researchers from the University of Michigan Marine Hydrodynamics Lab (MHL) and UMBS staff successfully launched a sensor buoy in Douglas Lake at the end of August. It is transmitting data, available on the MHL website, every ten minutes.
The buoy is a joint project between UMBS and the MHL funded by the Office of the Vice President for Research. It currently measures wind, air temp, barometric pressure, RH, solar radiation and surface water temp. It also carries a thermistor string to measure water temperature profiles at 8 depths.
Next year a YSI water quality sonde and an experimental port will be added. The YSI will measure conductivity, pH, DO, chlorophyll, turbidity and blue green algae. The experimental port will be available for sensor researchers to test developing sensors (the data will be logged and transmitted real-time).
In addition to live-streaming the data to the MHL website, the buoy also transmits data to the Great Lakes Observing System. | physics |
https://scentgraph.com/can-you-burn-a-jar-candle-if-the-jar-is-cracked/ | 2023-12-03T17:54:47 | s3://commoncrawl/crawl-data/CC-MAIN-2023-50/segments/1700679100508.42/warc/CC-MAIN-20231203161435-20231203191435-00631.warc.gz | 0.913896 | 1,575 | CC-MAIN-2023-50 | webtext-fineweb__CC-MAIN-2023-50__0__127374647 | en | Scented candles notch up aesthetics, make a cozy ambiance, offer aromatherapy benefits, and a lot more. That’s why we often end up shelling big bucks on these items. But, what if you discover a crack in the jar? I am sure the first thing that flashes into your mind is, can you burn a jar candle if the jar is cracked?
This question is important and quite relevant from the perspective of the consumer. You paid for an expensive candle, would it all be for nothing due to a crack in the jar? Glass is quite vulnerable to breakage. So, when you buy a delicate item like a jar candle, the risk of it getting damaged runs parallel.
Let’s talk of a few possible reasons that develop cracks into your jar candle
What Makes A Jar Candle Develop Cracks
The Jars Need Careful Handling
Glass is a useful material, but it can be temperamental.
A jar candle is prone to breakage or hairline cracks if you become a little reckless about its care and subsistence. The candles bumping into each other or something else during transport, or some rough handling could turn problematic. Heck, even accidentally using extra force when placing it on a table or shelf could make the jar crack.
When You Receive A Cracked Jar Candle Ordered Online
When you buy something online, the orders undergo a long process from shipment to delivery. Delicate items like glass candle jars are prone to damage during transit. There could be any number of reasons from improper packaging to mishandling, and accidents can happen during shipping and/or delivery.
You should contact the store for further action, including replacement. Most sellers have decent return and replacement policies.
Thermal Shock Is Not A Friend Of The Glass Jar Candle
Glass is a bad heat conductor and it can’t keep up with sudden temperature changes. This thermal shock expands the glass and leads to breakage or cracks in the jar as it finds no space for expansion. It’s a simple dynamics of Physics.
Another point to note down is that exposing the jar candles to direct sunlight for prolonged periods can also cause cracks in the jar.
Have You Been Storing Jar Candles In A Freezer?
Some people prefer to store candles in the freezer when not in use. The claim is that this (supposedly) keeps the wax in shape and protects the essential oils in scented candles.
During extreme summer, especially in hotter regions, wax in the glass jar may loosen its solid form. Few people place the jar candles in the freezer to harden the wax. As it makes the wax melt slowly, therefore increases the shelf life of the candle.
Coaxing the jar candles into burning longer is quite luring. But, it can result in cracking the jar. I’ve already discussed thermal shock, the same principle applies here.
In the freezer, the jar gets cold to its core. When you take it out to room temperature, it makes it difficult for the glass to adapt to this abrupt room temperature. The outside of the jar warms faster than the inside and this leads to major temperature differences inside and outside the jar. Lighting the candle before the glass has time to acclimate can cause cracks to develop.
In case you burn the frozen jar candle at once after taking it out of the freezer, the jar can explode too. Be cautious!
Prolonged Candle Burning Can Damage The Glass
There is no harm in burning candles every day. It’s absolutely a natural way to enjoy the aroma and relax. But, burning them for several hours can result in damage. It is usually advisable that you never burn your candles for more than four hours continuously to prevent excessive heat in the glass jar.
These are a few of the reasons that cause your jar candles to crack. However, after knowing the reasons now let’s come to the crux of the discussion: can you burn a jar candle if the jar is cracked.
Can You Burn A Jar Candle If The Jar Is Cracked?
Seeing a broken expensive jar candle is heartache and it may be quite tempting for you to take a risk and burn the candle anyway. But, Hold on! If you ever come across such a situation then I suggest abandoning the idea of burning a cracked jar candle.
Burning a candle in a cracked jar can cause the melted hot wax to seep through the cracks. This wax can be tough to clean and handle. Besides, it can further put pressure on the crack, causing the jar to explode. This won’t be a movie-style explosion, but it does pose some risks.
The most aggravated outcome of burning a cracked jar candle is a jar explosion. This can happen due to other reasons too which I will talk about next.
A Cracked Jar Candle Can Cause Jar Candle Explosion
Have you ever heard of a jar candle explosion? If you love candles and burn them often then this is a very cardinal piece of information for you. Here are some of the causes:
- Burning a candle in a cracked jar candle when the cracks are big and deep.
- Storing candles in a freezer to harden the wax and burning the wick right away.
- Trying to burn every bit of wax at the base of the jar. It overheats the glass to a point where it expands unusually and then breaks or blasts.
- Burning a jar candle for several hours (usually more than four hours, but it depends on the specific glass), can cause the jar to overheat or blast.
Jar candle explosions are dangerous enough to set your house on fire. Therefore, it is advisable to be cautious.
Can We Repurpose The Wax If The Candle Jar Is Cracked?
This thought is quite obvious after spending on an expensive candle. We can’t burn the cracked jar candle, but we don’t want to see it all go to waste either.
What about the solid wax? It is tempting enough to find a way to extract the wax out of the jar and repurpose it in creating a new candle.
Some people suggest different ways to scrape the wax out of the cracked jar candle and create a new candle out of it. I do not recommend it. The whole process is too time-consuming and quite laborious. Also, the broken jar candle may have tiny pieces of glass that can hurt your hands when you remove it from the jar.
However, if you see a possibility that the wax block is free from glass particles then yes you can try a convenient way to diffuse its scent and use the wax block. I’m talking about candle warmers (wax melters). Extract the wax by any one of the methods you find convenient. Use the scooped wax block in a wax warmer and let the essential oil release its scent.
How To Dispense Away With The Cracked Jar?
You must dispose of the jar in an environmentally friendly way. The first option is to wrap the broken jar in paper and drop it at a recycling plant. Glass is recyclable, but a broken jar may not be desirable. In such a situation, throw the glass jar in the garbage box there.
Never Burn A Jar Candle If The Jar Is Cracked
Wear and tear do happen to our favorite belongings which may be pretty expensive. And, your jar candle can be one of them. When it cracks and you have a striking question for yourself, can you burn a jar candle if the jar is cracked? The answer is a definite no. But not all is lost, and you can look at ways to salvage the wax and use it for some scent. | physics |
https://hqhp-en.com/zi_gong_si1 | 2022-05-29T04:59:15 | s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652663039492.94/warc/CC-MAIN-20220529041832-20220529071832-00774.warc.gz | 0.930189 | 359 | CC-MAIN-2022-21 | webtext-fineweb__CC-MAIN-2022-21__0__263652794 | en | Chengdu Craer Cryogenic Equipment Co., Ltd., established in 2008 and with a registered capital of CNY 30 million, is located in Chengdu National Economic and Technological Development Zone and currently has one research and development and production base in Chengdu of Sichuan, and one production base in Yibin of Sichuan.
The Company is a service provider specializing in the comprehensive utilization of natural gas and cryogenic insulation engineering. It is committed to the research and development, design, manufacture and sales of complete gas equipment and vacuum insulation products, is a national high-tech enterprise, and the technical center for the solution of vacuum insulated cryogenic pipeline system in air separation and energy industry in China. Its products are widely used in energy industry, air separation industry, metallurgy industry, chemical industry, machinery industry, medical treatment, national defense and other industries. It is the largest and technically advanced professional manufacturer of high vacuum multilayer insulation products in China.
The Company has the capacity to design pressure pipeline, the capacity of checking and analyzing stress in piping system, advanced mechanical processing equipment, vacuum pumping equipment and leak detection equipment ahead of others in the industry, and has strong strength in argon arc welding, helium mass spectrometer leak detection, high vacuum multilayer insulation technology and vacuum acquisition, etc. All of such advantages provide sufficient guarantee for the excellent quality of products. Its products have strong market competitiveness and its products have been sold in more than 20 provinces (cities and autonomous regions) in China. The Company has the export license and has successfully exported its products to Britain, Norway, Belgium, Italy, Singapore, Indonesia, Nigeria and other countries. | physics |
https://www.stm-groups.co.id/product/versatorr-bvt200-series-pirani-transducers-7251650 | 2024-02-29T00:01:44 | s3://commoncrawl/crawl-data/CC-MAIN-2024-10/segments/1707947474746.1/warc/CC-MAIN-20240228211701-20240229001701-00435.warc.gz | 0.852837 | 325 | CC-MAIN-2024-10 | webtext-fineweb__CC-MAIN-2024-10__0__179501067 | en | VersaTorr BVT200 Series Pirani Transducers
Ultra-wide range pirani/capacitance/piezo transducer with atmospheric switch function.
Establish new standards with the VersaTorr BVT200/225 Series Pirani transducer. This is an all-in-one wide range measurement solution for a broad selection of vacuum applications. It differentiates from any other vacuum gauges by offering an overall cost-effective gas independent measurement from 5.0E-3 to 1333 mbar in combination with measurement down to 1E-6 mbar by use of the heat-loss principle.
In vacuum applications where the gas composition or type can change, traditional gas dependent Pirani gauges will result in measurement deviation from the actual pressure. The Tri- Sensor transducer uses a precision capacitance diaphragm gauge (CDG) sensor that eliminates the gas dependency and provides accurate measurements also when the gas properties change.
The integrated heat-loss MEMS Pirani sensor extends the measuring range down to 1E-6 mbar and provides a novel automatic zero adjustment of the capacitance manometer that eliminates the common needs for manual zero adjustment of traditional capacitance diaphragm gauges.Features & Benefits:
- Ultra-wide measuring range of 9 decades
- Capacitance diaphragm adds increased accuracy at 0.5% through low vacuum range
- 6 decades of gas independent measurement from 5E-3 to 1333 mbar
- Automatic zeroing of capacitance manometer
- Vacuum temperature sensor for diagnostics | physics |
https://skillfulgown9418.wordpress.com/category/glasses/ | 2018-07-16T12:15:40 | s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676589270.3/warc/CC-MAIN-20180716115452-20180716135452-00418.warc.gz | 0.917288 | 520 | CC-MAIN-2018-30 | webtext-fineweb__CC-MAIN-2018-30__0__224099215 | en | IBMs new thin-film solar cell has broken a world record for having an efficiency of 9.6 percent.
The solar cell- made up of zinc, copper, tin and sulphur/selenium- has an efficiency rating that is 40 percent higher than older solar cells made up of the same materials. Thin film solar cells usually have a 9 to 11 percent efficiency rate, and usually come from very expensive elements like cadmium, gallium and indium.
In 2008, IBM developed the concentrating photovoltaic technology with the aim to reduce the cost of producing solar energy by using less photovoltaic cells in a solar farm and concentrating more light onto each cell using larger lenses. IBMs strategy comes from its capacity to cool the tiny solar cell and to concentrate the equivalent of 2000 suns on a small area for melting stainless steel. IBM also uses its technology for cooling computer chips which had enabled solar cells to cool from. https://www.google.com/fusiontables/embedviz?viz=GVIZ&t=TABLE&q=select+col0%2C+col1%2C+col2+from+1oLGf5T3iLrf_jWrrXp6rLe-08Z2eEu8FUMjWilZD&containerId=googft-gviz-canvas
greater than 1600 degrees Celsius to just 85 degrees Celsius.
IBM has also developed a system that achieved breakthrough results by combining a commercial solar cell with an advanced IBM liquid metal thermal cooling system using microprocessor industry methods.
The melted liquid metal called thermal interface layer is applied between the chip and the cooling block so that heat may be transferred and chip temperature may be kept low. The technology, which was developed by IBM originally to cool high power computer chips, gives an excellent thermal performance at a low cost.
CPV technology has the capacity to provide the lowest-cost solar electricity for large-scale power generation, as long as the temperature of the cells are kept low and cost-effective optics can be developed for concentrating the light to high levels.
Aside from photovoltaic research, IBM is also involved in energy efficient technology and services, advanced water management, carbon management, intelligent transportation systems and intelligent utility systems.
IBM Research lead photovoltaics scientist Dr. Supratik Guha said that he believes IBM can supply knowledge from their extensive experience in semiconductors and nanotechnology to the field of alternative energy research. | physics |
https://hlpcontrols.com.au/product/274/professional-digital-light-meter-to-20000-lux | 2021-12-07T21:05:12 | s3://commoncrawl/crawl-data/CC-MAIN-2021-49/segments/1637964363418.83/warc/CC-MAIN-20211207201422-20211207231422-00550.warc.gz | 0.778129 | 230 | CC-MAIN-2021-49 | webtext-fineweb__CC-MAIN-2021-49__0__115915964 | en | Professional Digital Light Meter to 20,000 Lux
T1337 - Digital Light Meter. Accurate and instant response with data hold & min / max functions.
Send an Enquiry
Please use this form if you have questions about our products and we'll get back with you very soon.
Digital Light meter with spectral sensitivity close to CIE photopic curve.
- Reads in LUX & FC
- Max 20,000 lux
- Over range will display: LCD will show "OL" symbol
- Resolution 0.01lux
- Data Hold,
- Minimum / Maximum
- Separate light sensor on curley cord so that sensor can be held in the place where the reading needs to be taken and the digital display can be viewed by the user.
Other products you might be interested in
Sound Pressure Level Meter to 130dB
Model : 8922
Laser Distance Measurer to 40M
Model : CA740
Electro Magnetic Field (EMF) 'Smog' Tester
Model : T92 | physics |
https://www.ivoryegg.co.uk/shop/products/theben-meteodata-139-knx-weather-forecast-reciever?taxon_id=56 | 2020-06-04T18:12:25 | s3://commoncrawl/crawl-data/CC-MAIN-2020-24/segments/1590347445880.79/warc/CC-MAIN-20200604161214-20200604191214-00309.warc.gz | 0.738576 | 522 | CC-MAIN-2020-24 | webtext-fineweb__CC-MAIN-2020-24__0__159810072 | en | Meteodata 139 KNX
Delivery of the data via HKW Elektronik GmbH in cooperation with the Europäischen Funk-Rundsteuerung (EFR) [European Radio Ripple Control].
Including weather data licence, no ongoing additional costs for the weather data.
- Range: Each about 800 Kkilometres around the three transmitters Mainflingen in Frankfurt am Main, Burg in Magdeburg and Lakihegy in Budapest.
- LED for status display of the reception quality.
The following data are available for each weather region:
- Air temperature
- Precipitation amount
- Precipitation probability
- Wind force
- Wind direction
- Sunshine duration
- Solar insolation
- Weather scenario as text
- Weather scenario as scene number
This data is divided up into 6 h periods for each day. The entire forecast period extends across 4 days, as follows:
- Day (day 0)
- The day after tomorrow
- In 3 days
A bad weather warning can be given depending on the expected wind/gust strength or precipitation amount.
The EFR time service makes the device the ideal timekeeper: Very brief synchronisation time (approx. 2 s). Both the standard time format (separate objects for time and date) and the
Optimal energy-saving options via:
- Messages about the expected solar yield, i.e. coordination between solar system and heat generator (heating boiler).
- Automatic changeover in the heating system from winter to summer mode (and reverse) based on the current weather situation taking into the external temperature and the heat of the sun (sunshine duration or solar radiation in W/m2)
- Heating and cooling support for optimal use of the solar heat e.g. for blind controls.
- Bus Voltage: KNX Bus 21...30VDC
- Bus Current Consumption: 12mA
- Air Temperature Range: -60...+55°C
- Precipitation Range: 0- >60mm or l/m2
- Precipitation Probability: 0-100%
- Wind: 1-12 BFT (2 km/h..>117 km/h)
- Wind Direction: 360°
- Sunshine Duration: 0-6h
- Solar Insolation: 0-12000 W/m2
- Weather Scenarios: 15 Weather Symbols + Text
|Operating voltage||KNX Bus (29VDC)| | physics |
http://s-gard.com.my/faq | 2020-04-02T11:39:05 | s3://commoncrawl/crawl-data/CC-MAIN-2020-16/segments/1585370506959.34/warc/CC-MAIN-20200402111815-20200402141815-00551.warc.gz | 0.908423 | 639 | CC-MAIN-2020-16 | webtext-fineweb__CC-MAIN-2020-16__0__29590778 | en | FREQUENTLY ASKED QUESTIONS
Q: What is the law regarding tinting of motor vehicles in Malaysia?
A:According to the JPJ, the regulations require a minimum of 70% Visible Light Transmission (VLT) for the front windscreen and a minimum of 50% for the sides and rear windscreen. However, the new regulation that will be implemented from May 1, 2015 states that the rear windscreen and rear passenger windows’ to have 30% VLT.
Q: What is VLT?
A:VLT is Visible Light Transmission. VLT is the amount of visible light that passes directly through filmed glass. The darker the tint, the lower the visible light transmitted.
Q: What is TSER?
A:Total Solar Energy Rejected (TSER) is the percentage of the total solar energy that is rejected. TSER includes visible light, infrared radiation and ultraviolet energy. The higher the percentage, the higher the percentage of solar energy deflected. Most tinting shops use Infra Red Rejection (IRR) as a guide to the level of heat rejection. However, IRR only covers a fraction of TSER. Internationally, TSER is used as a guide as it is a more accurate way of measuring heat rejection.
Q: What is Ultraviolet (UV) Rejection?
A:Ultraviolet Rejection is the percentage of ultraviolet energy deflected away from the window film. Ultraviolet rays can cause upholstery and furnishings to fade. It can also cause skin damage and skin cancer.
Q: Security/Safety Films – Basics
A:The performance of Security/Safety films rely solely on the thickness of the film. Thicker films will endure a higher breaking point, i.e. absorbing higher impact forces in terms of LB/inch² (pound per square inch), making harder it to penetrate the window. Thickness of Security/Safety films are measured in terms of “Mil” (1 Mil = 25 Microns = 0.025 Millimeter). S-GARD providing Security/Safety films ranging from the lower end of 4Mil to the highest of 6Mil.
Q: Why should I choose S-GARD?
A:When you choose S-GARD, you’re not just choosing a window film, you’re choosing a premium product with high performance plus the service provided and the factory backed warranty, which lasts for 5 years.
Q: Is there anything I have to look out for after installation?
A:After installation, it is advisable to keep your windows closed for a minimum of 48 hours. There might be watermarks present, which will disappear in a couple of days. If you should decide to remove the tint, there will be no permanent stains on the glass. Any leftover adhesive can be easily removed with cleaning agents.
Q: What does the warranty cover?
A:Warranty for all tints covers bubbles, peeling, oxidisation, discolorization and cracking. Depending on the tint, the warranty period can range from up to 5 years. | physics |
http://www.nofp.com/insulation-products/microvent | 2021-10-22T07:23:50 | s3://commoncrawl/crawl-data/CC-MAIN-2021-43/segments/1634323585460.87/warc/CC-MAIN-20211022052742-20211022082742-00658.warc.gz | 0.869247 | 397 | CC-MAIN-2021-43 | webtext-fineweb__CC-MAIN-2021-43__0__145061909 | en | Literature & Info
¼” MicroVent™ roll sizes
- 4’ x 125’ (500 sqft)
- Foil no scrim reinforcement
MicroVent is a perforated radiant barrier and reflective insulation that provides increased comfort, and energy efficiency when used in applications requiring a breathable material. The perforations are for breathability under vinyl siding or in attics where condensation may occur.
MicroVent effectively reflects a radiant heat source as opposed to absorbing and dissipating it as other insulations must do. This reflectivity works both ways: radiating summer heat outward and retaining winter heat inside. When used behind vinyl siding in new installations or in retro-fit, you can increase the overall wall assembly insulation levels as opposed to using fan-fold. In addition, when used in an attic, you can expect lower attic temperatures thereby reducing the summer heat gain or winter heat loss. MicroVent helps the insulation currently in your attic work more efficiently for year round comfort..
EASY TO USE (Self-Taping)
MicroVent is made from a multi-ply polymeric core material that is lighter weight and easier to handle than other reflective or fiber glass insulation products. In addition, the factory applied self-taped edge makes installation fast and efficient
SMOOTH FINISHED SURFACES for use behind Vinyl Siding
MicroVent provides a smooth finish for the installation of vinyl siding. Incorporating an air-space on both sides of MicroVent allows for optimum insulating value.
When installed correctly, MicroVent provides an excellent thermal barrier, greatly reducing condensation buildup and with the addition of a perforated facing, allows for accumulated moisture to escape.
SIMPLE, SAFE INSTALLATION
MicroVent requires only a pair of scissors or utility knife and a staple gun. It does not require masks or long clothing for installation. | physics |
https://www.ikprress.org/index.php/AJOMCOR/article/view/7184 | 2022-05-16T05:54:32 | s3://commoncrawl/crawl-data/CC-MAIN-2022-21/segments/1652662509990.19/warc/CC-MAIN-20220516041337-20220516071337-00457.warc.gz | 0.722533 | 860 | CC-MAIN-2022-21 | webtext-fineweb__CC-MAIN-2022-21__0__80745790 | en | MODELING THE MOVEMENT OF GROUNDWATER IN A RECTANGULAR JUMPER WITH A SCREEN
Asian Journal of Mathematics and Computer Research,
Abstract. Within the framework of planar steady-state filtration of incompressible fluid according to Darcy's law, an exact analytical solution of the problem of flow in a rectangular cofferdam with a screen in the presence of evaporation from the free surface of groundwater is given. The limiting cases of the considered motion - filtration in unconfined reservoir to imperfect gallery, as well as the flow in the absence of evaporation - are noted.
- Groundwater movement
- rectangular jumper
- filtration theory
- tube well
How to Cite
Numerov SN. Theory of motion of liquids and gases in a non-deformable porous medium. Moscow: Gostekhizdat. 1953;616с.
Development of studies on filtration theory in the USSR (1917-1967) / Ed. by P.Y. Polubarinova-Kochina. Moscow: Nauka. 1967;545с.
Mikhailov G.K., Nikolaevsky V.N. In: Mechanics in the USSR for 50 Years. Moscow: Nauka, 1970. Т. 2. С. 585 –648.
Polubarinova-Kochina P Ya, Pryazhinskaya VG, Emikh VN. Mathematical methods in matters of irrigation. Moscow: Nauka. 1969;414 с.
Kochina P Ya. Selected works. Hydrodynamics and Filtration Theory. Moscow: Nauka. 1991;351с.
Pryazhinskaya VG. Groundwater motion in a rectangular cofferdam with an impermeable vertical wall // Izv. Mechanics and Engineering. 1964;4: 41–49.
Polubarinova-Kochina P Ya , Postnov VA, Emikh N, Emikh VN. The steady-state filtration to an imperfect gallery in an unpressurized reservoir // Izv. MZHG. 1967;4:97–100.
Bereslavsky EN, Dudina LM. On the motion of groundwater to an imperfect gallery in the presence of evaporation from a free surface // Vestnik S.-Petersburg. Un. Series 1. Mathematics. Mechanics. Astronomy. 2017;4,4(62):654–663.
Bereslavsky EN. On some Fuchs class equations in hydro- and aeromechanics // Izv. MJG. 1992;5:3–7.
Kochina P Ya , Bereslavsky EN, Kochina NN. Analytic theory of Fuchs class linear differential equations and some problems of underground hydromechanics. Preprint No. 567. М, Institute of Mechanics Problems. Moscow: Institute for Problems of Mechanics of The Russian Academy of Sciences. 1996;1:122 .
Bereslavsky EN. On differential equations of Fuchs class encountered in some problems of mechanics of liquids and gases // Izv. MJG. 1997;5:9–17.
Bereslavsky EN. On closed form integration of some fuchs class differential equations encountered in hydro-paeromechanics // DAN. 2009;428(4)439–443.
Golubev VV. Lectures on the analytic theory of differential equations. Gostekhizdat ML. 1950;436.
Bereslavsky EN, Likhacheva NV. Mathematical modeling of filtration from canals and sprinklers // Vestnik S.-Petersburg. Un-tat. Series 10. Appl. Inform. Proce. of Control. 2012;3:10-22.
Bereslavsky EN, Dalinger JM, Dudina LM. Modeling of groundwater motion. Technical Sciences. 2020;490(1):57-62.
Abstract View: 189 times
PDF Download: 3 times | physics |
https://moodle.ciu.edu.tr/course/info.php?id=4567 | 2023-03-20T18:10:59 | s3://commoncrawl/crawl-data/CC-MAIN-2023-14/segments/1679296943555.25/warc/CC-MAIN-20230320175948-20230320205948-00677.warc.gz | 0.923347 | 129 | CC-MAIN-2023-14 | webtext-fineweb__CC-MAIN-2023-14__0__60928425 | en | The objective of this course is to provide students with a solid grounding in the classical and modern theories of convective heat and fluid flows. The emphasis is on both the laminar and turbulent boundary-layer heat and fluid flows. During the course laminar and turbulent heat transfer for flow in ducts will be discussed and the foundation of statistical theory of turbulence will be examined. Also, the problem of turbulent boundary layer flow over a flat plate in the presence of heat transfer will be described. Finally, the problem of heat transfer by natural convection for both laminar and turbulent boundary layer flow over a vertical hot wall will be described. | physics |
http://realbraintruth.com/deconstructing-golf-clubs/ | 2019-05-24T13:40:53 | s3://commoncrawl/crawl-data/CC-MAIN-2019-22/segments/1558232257624.9/warc/CC-MAIN-20190524124534-20190524150534-00276.warc.gz | 0.969681 | 782 | CC-MAIN-2019-22 | webtext-fineweb__CC-MAIN-2019-22__0__67639532 | en | Golf is one of the most popular individual sports on the planet. The objective of the game is simple enough: complete an 18-hole golf course using as few moves as possible. The one who completes the course with the fewest moves (and therefore the lowest score) wins. Even though the game sounds very easy, it is actually far from being easy. Just step into the fairways to see what we mean by that. The main weapon of golfers to traverse golf courses is his set of golf clubs. To better understand how these clubs works visit rockbottomgolf.com, it would be great to take a closer look on how they are constructed.
The golf club existed for as long as the game has existed. There used to be a time when clubs are made exclusively of wood and players carry up to 30 of them in a golf course. However, with improvements in both technology and the understanding of the game, the way clubs are made has also evolved together with the game. The predominantly wood structure of golf clubs have been replaced by materials ranging from metal alloy to carbon fiber, making them stronger, more durable, and more precise in striking the ball. Also, golf club technology has advanced so much that you won’t have to carry too many clubs. All you need is at most 14 (the number mandated by official golf rules) and you’ll have more than enough tools to complete a golf course efficiently.
According to regulations, there are 5 classifications of golf clubs. Each classification is found in different forms, and it’s up to the golfer to pick which ones he/she is most comfortable with as he/she heads out in the golf course.
The 5 classes of golf clubs are as follows.
Woods are designed to carry the ball at a maximum distance. It is mainly designed for firing drives, where getting as close to the hole as possible using a single shot is necessary. They have long shafts and large, hollow heads, ideal for transmitting as much force as possible to the ball, launching it as long as the player’s swing would allow.
The iron is the club that possesses the most variations. Irons have shorter shafts compared to woods, which is necessary for better ball control. They have flattened heads that have an angle face, which is essential to propel the ball upwards for a trajectory motion. Different irons have different numbers which correspond to how high they can loft the ball upwards.
The hybrid club is considered as a modern innovation. The aim for constructing this club is to combine the great characteristics of a wood and an iron in a single club. The resulting club has the ability to launch the ball at a long distance while still giving considerable loft on the ball. The hybrid is so effective that it rendered some variants of woods and irons redundant.
This club is mainly designed for putting the ball. It has a short shaft that allows for precision aiming and a flat head with a minimal loft of 10 degrees or less. With this combination, the putter causes the ball to gently roll along the surface and into the target hole. Various innovations, ranging from face grooves to dual striker faces, are aimed towards improving putt stability.
The chipper is basically a modified version of the putter. Featuring a head that has an increased loft, it causes the ball to bounce upon impact then roll gently upon landing. The chipper is used when you’ll need to overcome a small obstacle to reach a portion of the green that’s close to the hole. Mastering the chipper is a potentially great way to complete a hole.
Golf clubs can come in all shapes and sizes, and each may come in handy when the game is on the line. It would be up to you to choose which set of clubs you are most comfortable with. | physics |
https://higheredleadership.wordpress.com/2012/06/05/all-about-parallax/ | 2018-07-20T21:59:13 | s3://commoncrawl/crawl-data/CC-MAIN-2018-30/segments/1531676591837.34/warc/CC-MAIN-20180720213434-20180720233434-00169.warc.gz | 0.942573 | 436 | CC-MAIN-2018-30 | webtext-fineweb__CC-MAIN-2018-30__0__254263009 | en | In a few hours, the Transit of Venus will begin. Why do we care about this rare astronomical event? The reasons are mostly historical. Back in the 1600’s, the data from observing Venus passing between the Sun and Earth (“transiting across the face of the Sun”), from multiple locations on Earth, were important to figuring out the distance from the Sun to Earth – and therefore beginning to understand the size of the Solar System. It’s all about parallax.
Technically, parallax is the apparent change in position and appearance of an object when viewed from a different location. Parallax gives humans stereoscopic vision and depth perception. Animals whose eyes do not have overlapping fields of view move their heads to get different perspectives on what they are seeing. On a larger scale, parallax has been important in astronomy to measure distances to the Moon, Sun, and other stars.
The concept of parallax is important for leaders, too. Leaders learn more about a subject by looking at it from multiple perspectives — by seeing it through the lenses of other people, other places, and other times. Sometimes, a topic or issue or possible solution looks the same from many viewpoints, but sometimes the view changes dramatically depending on the perspective. Triangulating on the most comprehensive description and the best solution by incorporating parallax can result in better understanding and more effective decisions.
When I was in Tahiti, a number of years ago, I visited the site where James Cook observed the Transit in 1769; contemporary reports suggest that the wonders of the Transit paled in comparison to those of the island and its people. NASA has a good summary of this event and its significance at this URL: http://science.nasa.gov/science-news/science-at-nasa/2012/02jun_jamescook/. After today’s 2012 Transit, the next one doesn’t occur until 2117.
Just remember not to look directly at the Sun. Even for leaders who are interested in gathering as much information as possible, permanent vision damage isn’t worth it. | physics |
https://centreforspirituality.org/events/the-yoga-of-the-christ-the-mystical-gospel-of-john-seen-through-eastern-eyes/ | 2024-02-22T00:28:46 | s3://commoncrawl/crawl-data/CC-MAIN-2024-10/segments/1707947473598.4/warc/CC-MAIN-20240221234056-20240222024056-00729.warc.gz | 0.930044 | 297 | CC-MAIN-2024-10 | webtext-fineweb__CC-MAIN-2024-10__0__40812699 | en | Come and explore the wisdom of one of the world’s great spiritual texts. The Gospel of John is much more cosmological and mystical in nature than the other gospels.
We are delighted to have Professor Ravi Ravindra, author of the ‘Gospel of John in the Light of Indian Mysticism’, lead this evening’s talk. Ravi will open our evening’s reflections with a guided meditation, followed by a talk and then an opportunity for dialogue.
Professor Ravi Ravindra is Professor Emeritus at Dalhousie University, Halifax, Canada, where he was Professor and Chair of Comparative Religion and Adjunct Professor of Physics. In addition to a profound study of the great faith traditions, Ravi Ravindra has had a longstanding engagement with spirituality. Ravi holds master’s degrees in technology, physics and philosophy and a Ph.D. in physics. He has been a Member of the Institute of Advanced Study at Princeton University, and a Fellow of the Indian Institute of Advanced Study in Shimla. Ravi is the author many books including ‘Yogas of the Chirst: an Introduction to the Gospel of St. John’ ‘Science and the Sacred: Eternal Wisdom in a Changing World’ and ‘Whispers from the Other Shore: Spiritual Search East and West’.
Tickets available on the door: £6 standard / £4 concessions. | physics |
Subsets and Splits
No saved queries yet
Save your SQL queries to embed, download, and access them later. Queries will appear here once saved.