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1

High temperature measuring device  

DOEpatents

A temperature measuring device for very high design temperatures (to 2,000.degree. C.). The device comprises a homogenous base structure preferably in the form of a sphere or cylinder. The base structure contains a large number of individual walled cells. The base structure has a decreasing coefficient of elasticity within the temperature range being monitored. A predetermined quantity of inert gas is confined within each cell. The cells are dimensionally stable at the normal working temperature of the device. Increases in gaseous pressure within the cells will permanently deform the cell walls at temperatures within the high temperature range to be measured. Such deformation can be correlated to temperature by calibrating similarly constructed devices under known time and temperature conditions.

Tokarz, Richard D. (West Richland, WA)

1983-01-01

2

High-temperature-measuring device  

DOEpatents

A temperature measuring device for very high design temperatures (to 2000/sup 0/C) is described. The device comprises a homogenous base structure preferably in the form of a sphere or cylinder. The base structure contains a large number of individual walled cells. The base structure has a decreasing coefficient of elasticity within the temperature range being monitored. A predetermined quantity of inert gas is confined within each cell. The cells are dimensonally stable at the normal working temperature of the device. Increases in gaseous pressure within the cells will permanently deform the cell walls at temperatures within the high temperature range to be measured. Such deformation can be correlated to temperature by calibrating similarly constructed devices under known time and temperature conditions.

Not Available

1981-01-27

3

Low Temperature Photocurrent Measurements in Graphene Devices  

NASA Astrophysics Data System (ADS)

The Dirac-like chiral nature of charge carriers in graphene has been linked to a number of unusual charge transport phenomena, including suppression of localization and minimum conductivity. A crucial ingredient to understand such phenomena in graphene is the ability to correlate the charge transport characteristics with the corresponding internal potential landscape and band-bending. With a scanning optical microscope operated at LHe temperature we have measured lateral photo-current in graphene-based devices. Spatial maps of photocurrent obtained using this approach contain information about the distribution of lateral electrostatic fields in these devices. At room temperature, band-bending induced by metal contacts has been observed. At cryogenic temperature, formation of electron-hole puddles leads to spatially inhomogeneous maps of photocurrent, which become very sensitive to the applied gate voltage.

Nazin, George; Zhang, Yan; Zhang, Liyuan; Sutter, Peter

2010-03-01

4

Miniature ingestible telemeter devices to measure deep-body temperature  

NASA Technical Reports Server (NTRS)

A telemetry device comprised of a pill-size ingestible transmitter developed to obtain deep body temperature measurements of a human is described. The device has particular utility in the medical field where deep body temperatures provide an indication of general health.

Pope, J. M.; Fryer, T. B. (inventors)

1976-01-01

5

46 CFR 154.1375 - Readout for temperature measuring device: Marking.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Readout for temperature measuring device: Marking. 154...Instrumentation § 154.1375 Readout for temperature measuring device: Marking. Each...154.1340 for a device that measures temperature in a cargo tank must be marked...

2014-10-01

6

46 CFR 154.1375 - Readout for temperature measuring device: Marking.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Readout for temperature measuring device: Marking. 154...Instrumentation § 154.1375 Readout for temperature measuring device: Marking. Each...154.1340 for a device that measures temperature in a cargo tank must be marked...

2013-10-01

7

46 CFR 154.1375 - Readout for temperature measuring device: Marking.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Readout for temperature measuring device: Marking. 154...Instrumentation § 154.1375 Readout for temperature measuring device: Marking. Each...154.1340 for a device that measures temperature in a cargo tank must be marked...

2010-10-01

8

46 CFR 154.1375 - Readout for temperature measuring device: Marking.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Readout for temperature measuring device: Marking. 154...Instrumentation § 154.1375 Readout for temperature measuring device: Marking. Each...154.1340 for a device that measures temperature in a cargo tank must be marked...

2012-10-01

9

46 CFR 154.1375 - Readout for temperature measuring device: Marking.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Readout for temperature measuring device: Marking. 154...Instrumentation § 154.1375 Readout for temperature measuring device: Marking. Each...154.1340 for a device that measures temperature in a cargo tank must be marked...

2011-10-01

10

21 CFR 882.1570 - Powered direct-contact temperature measurement device.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Powered direct-contact temperature measurement...Neurological Diagnostic Devices § 882.1570 Powered direct-contact temperature measurement device. (a) Identification. A powered direct-contact temperature...

2013-04-01

11

21 CFR 882.1570 - Powered direct-contact temperature measurement device.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Powered direct-contact temperature measurement...Neurological Diagnostic Devices § 882.1570 Powered direct-contact temperature measurement device. (a) Identification. A powered direct-contact temperature...

2011-04-01

12

Thermal measurement. Nanoscale temperature mapping in operating microelectronic devices.  

PubMed

Modern microelectronic devices have nanoscale features that dissipate power nonuniformly, but fundamental physical limits frustrate efforts to detect the resulting temperature gradients. Contact thermometers disturb the temperature of a small system, while radiation thermometers struggle to beat the diffraction limit. Exploiting the same physics as Fahrenheit's glass-bulb thermometer, we mapped the thermal expansion of Joule-heated, 80-nanometer-thick aluminum wires by precisely measuring changes in density. With a scanning transmission electron microscope and electron energy loss spectroscopy, we quantified the local density via the energy of aluminum's bulk plasmon. Rescaling density to temperature yields maps with a statistical precision of 3 kelvin/hertz(-1/2), an accuracy of 10%, and nanometer-scale resolution. Many common metals and semiconductors have sufficiently sharp plasmon resonances to serve as their own thermometers. PMID:25657242

Mecklenburg, Matthew; Hubbard, William A; White, E R; Dhall, Rohan; Cronin, Stephen B; Aloni, Shaul; Regan, B C

2015-02-01

13

Silicon device performance measurements to support temperature range enhancement  

NASA Technical Reports Server (NTRS)

Semiconductor power devices are typically rated for operation below 150 C. Little data is known for power semiconductors over 150 C. In most cases, the device is derated to zero operating power at 175 C. At the high temperature end of the temperature range, the intrinsic carrier concentration increases to equal the doping concentration level and the silicon behaves as an intrinsic semiconductor. The increase in intrinsic carrier concentration results in a shift of the Fermi level toward mid-bandgap at elevated temperatures. This produces a shift in devices characteristics as a function of temperature. By increasing the doping concentration higher operating temperatures can be achieved. This technique was used to fabricate low power analog and digital devices in silicon with junction operating temperatures in excess of 300 C. Additional temperature effects include increased p-n junction leakage with increasing temperature, resulting in increased resistivity. The temperature dependency of physical properties results in variations in device characteristics. These must be quantified and understood in order to develop extended temperature range operation.

Bromstead, James; Weir, Bennett; Johnson, R. Wayne; Askew, Ray

1991-01-01

14

Improvement of the operation rate of medical temperature measuring devices  

NASA Astrophysics Data System (ADS)

A method of reducing measuring time of temperature measurements of biological objects based on preheating the resistance temperature detector (RTD) up to the temperature close to the temperature to be measured, is proposed. It has been found that at the same measuring time, the preheating allows to decrease the measurement error by a factor of 5 to 45 over the temperature range of 35-41°?. The measurement time is reduced by 1.6-4 times over this range, keeping the same value of the measurement error.

Hotra, O.; Boyko, O.; Zyska, T.

2014-08-01

15

Silicon device performance measurements to support temperature range enhancement  

NASA Technical Reports Server (NTRS)

The results of the NPN bipolar transistor (BJT) (2N6023) breakdown voltage measurements were analyzed. Switching measurements were made on the NPN BJT, the insulated gate bipolar transistor (IGBT) (TA9796) and the N-channel metal oxide semiconductor field effect transistor (MOSFET) (RFH75N05E). Efforts were also made to build a H-bridge inverter. Also discussed are the plans that have been made to do life testing on the devices, to build an inductive switching test circuit and to build a dc/dc switched mode converter.

Johnson, R. Wayne; Askew, Ray; Bromstead, James; Weir, Bennett

1991-01-01

16

High resolution direct measurement of temperature distribution in silicon nanophotonics devices.  

PubMed

Following the miniaturization of photonic devices and the increase in data rates, the issues of self heating and heat removal in active nanophotonic devices should be considered and studied in more details. In this paper we use the approach of Scanning Thermal Microscopy (SThM) to obtain an image of the temperature field of a silicon micro ring resonator with sub-micron spatial resolution. The temperature rise in the device is a result of self heating which is caused by free carrier absorption in the doped silicon. The temperature is measured locally and directly using a temperature sensitive AFM probe. We show that this local temperature measurement is feasible in the photonic device despite the perturbation that is introduced by the probe. Using the above method we observed a significant self heating of about 10 degrees within the device. PMID:24514471

Tzur, Mor; Desiatov, Boris; Goykhman, Ilya; Grajower, Meir; Levy, Uriel

2013-12-01

17

Silicon device performance measurements to support temperature range enhancement  

NASA Technical Reports Server (NTRS)

Testing of the metal oxide semiconductor (MOS)-controlled thyristor (MCT) has uncovered a failure mechanism at elevated temperature. The failure appears to be due to breakdown of the gate oxide. Further testing is underway to verify the failure mode. Higher current level inverters were built to demonstrate 200 C operation of the N-MOSFET's and insulated-gate-bipolar transistors (IGBT's) and for life testing. One MOSFET failed early in testing. The origin of this failure is being studied. No IGBT's have failed. A prototype 28-to-42 V converter was built and is being tested at room temperature. The control loop is being finalized. Temperature stable, high value (10 micro-F) capacitors appear to be the limiting factor in the design at this time. In this application, the efficiency will be lower for the IGBT version due to the large V sub(cesat) (3.5-4 V) compared to the input voltage of 28 V. The MOSFET version should have higher efficiency; however, the MOSFET does not appear to be as robust at 200 C. Both versions are built for comparison.

Bromstead, James; Weir, Bennett; Johnson, R. Wayne; Askew, Ray

1992-01-01

18

[Development of electronic clinical device for concentrated measurement of body temperature].  

PubMed

An kind of device for concentrated measurement of body temperature which takes ATmega16 microcontroller as the core is designed according to the current situation of measuring body temperature in the hospitals of our country. Taking DS18B20 as the transducer, the device uses PTR8000 wireless communication module to realize the communication from multi-point to single-point. Meanwhile photoelectric detection and USB interfaces are added in the design. Clock chip PCF8563, voice chip ISD1820 and LCD screen I JM12864M are used to realize the functions such as timekeeping, playing voice and displaying and so on. PMID:20352913

Zhang, Xu; Ouyang, Bin-lin

2009-11-01

19

High temperature spintronic devices  

NASA Astrophysics Data System (ADS)

Spintronics is a rapidly developing multidisciplinary field which investigates avenues of exploiting the spin degree of freedom in charge carriers and the nucleus of atoms to design novel devices that would outperform existing ones based on complementary-metal-oxide-semiconductor (CMOS) technology. Spin-polarized semiconductor based coherent light sources promise an ability to predict, stabilize and control orthogonal polarization states with reduced input power requirements. This doctoral thesis investigates different aspects of design, epitaxial growth, fabrication, characterization and modeling of spin based electronic and optoelectronic devices working near room temperature. We have demonstrated the modulation of magnetoresistance in an InAs/ In0.53Ga0.47As/ In0.52Al0.48As lateral spin valve with a gate electrode placed alongside the MnAs polarizer contact and outside the current transport channel. The results indicate that the change in magnetoresistance is caused, in part, by Rashba spin-orbit coupling due to the gate bias. In order to achieve higher working temperatures devices for real world applications MnAs/GaAs/MnAs based vertical spin valves have been realized. We have attributed the near room temperature operation of these devices to valence band electron tunneling of spin polarized carriers in and out of a heavily p-doped GaAs:Mn layer. Peak magnetoresistance of 40 % and 1 % have been observed at 10 K and 300 K respectively. The continuous wave, transient and high frequency dynamics of spin-polarized carriers and photons in a spin laser have been studied. Besides lowering of threshold currents, it has been theoretically estimated that these devices can show larger small-signal modulation bandwidth and 100% output polarization, independent of the injected carrier spin polarization, under appropriate biasing conditions. Measurements were done at 230 K on a InAs/GaAs quantum dot spin vertical cavity surface emitting laser (VCSEL). A time-averaged output polarization of 55% is measured with an active region spin polarization of 5-6%. A peak threshold current reduction of 4.5 % and a polarization modulation index of 0.6 have been measured in these devices under continuous wave bias. The measured output characteristics, both DC and transient, match very well with those calculated from theory.

Basu, Debashish

20

Device and method for self-verifying temperature measurement and control  

DOEpatents

A measuring instrument includes a first temperature sensor, a second temperature sensor and circuitry. The first and second temperature sensors each generate a signal indicative of the temperature of a medium being detected. The circuitry is configured to activate verification of temperature being sensed with the first sensor. According to one construction, the first temperature sensor comprises at least one thermocouple temperature sensor and the second temperature sensor comprises an optical temperature sensor, each sensor measuring temperature over the same range of temperature, but using a different physical phenomena. Also according to one construction, the circuitry comprises a computer configured to detect failure of one of the thermocouples by comparing temperature of the optical temperature sensor with each of the thermocouple temperature sensors. Even further, an output control signal is generated via a fuzzy inference machine and control apparatus.

Watkins, Arthur D. (Idaho Falls, ID); Cannon, Collins P. (Kearney, MO); Tolle, Charles R. (Idaho Falls, ID)

2002-10-29

21

Impact of temperature on single event upset measurement by heavy ions in SRAM devices  

NASA Astrophysics Data System (ADS)

The temperature dependence of single event upset (SEU) measurement both in commercial bulk and silicon on insulator (SOI) static random access memories (SRAMs) has been investigated by experiment in the Heavy Ion Research Facility in Lanzhou (HIRFL). For commercial bulk SRAM, the SEU cross section measured by 12C ions is very sensitive to the temperature. The temperature test of SEU in SOI SRAM was conducted by 209Bi and 12C ions, respectively, and the SEU cross sections display a remarkable growth with the elevated temperature for 12C ions but keep constant for 209Bi ions. The impact of temperature on SEU measurement was analyzed by Monte Carlo simulation. It is revealed that the SEU cross section is significantly affected by the temperature around the threshold linear energy transfer of SEU occurrence. As the SEU occurrence approaches saturation, the SEU cross section gradually exhibits less temperature dependency. Based on this result, the experimental data measured in HIRFL was analyzed, and then a reasonable method of predicting the on-orbit SEU rate was proposed.

Tianqi, Liu; Chao, Geng; Zhangang, Zhang; Fazhan, Zhao; Song, Gu; Teng, Tong; Kai, Xi; Gang, Liu; Zhengsheng, Han; Mingdong, Hou; Jie, Liu

2014-08-01

22

Rock massif temperature changes measurement with regard to thermal responses generated by a thermal response test device  

NASA Astrophysics Data System (ADS)

In this article are presented results from application of fiber optical DTS system within long term research of temperature energy accumulation in Paskov rock massif. In this area was established special measuring station for that purpose, because rock massif in Paskov area has ideal properties for temperature changes measurement. The twelve geothermal boreholes were drilled during this research, which were then used for rock massif heating by Thermal Response Test device. With the help of DTS system was observed how the temperature distribution and penetration in between boreholes in rock massif is. Thanks to the DTS system we were able to determine the Thermal Response Test device heating power influence on the nearest monitoring boreholes.

Latal, Jan; Vitasek, Jan; Koudelka, Petr; Siska, Petr; Liner, Andrej; Papes, Martin; Witas, Karel; Hejduk, Stanislav; Vasinek, Vladimir

2013-05-01

23

A robust and well shielded thermal conductivity device for low temperature measurements  

SciTech Connect

We present a compact mechanically robust thermal conductivity measurement apparatus for measurements at low temperatures (<1 K) and high magnetic fields on small high-purity single crystal samples. A high-conductivity copper box is used to enclose the sample and all the components. The box provides protection for the thermometers, heater, and most importantly the sample increasing the portability of the mount. In addition to physical protection, the copper box is also effective at shielding radio frequency electromagnetic interference and thermal radiation, which is essential for low temperature measurements. A printed circuit board in conjunction with a braided ribbon cable is used to organize the delicate wiring and provide mechanical robustness.

Toews, W. H.; Hill, R. W. [GWPI and Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)] [GWPI and Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

2014-04-15

24

Localized Heating on Silicon Field Effect Transistors: Device Fabrication and Temperature Measurements in Fluid  

PubMed Central

We demonstrate electrically addressable localized heating in fluid at the dielectric surface of silicon-on-insulator field-effect transistors via radio-frequency Joule heating of mobile ions in the Debye layer. Measurement of fluid temperatures in close vicinity to surfaces poses a challenge due to the localized nature of the temperature profile. To address this, we developed a localized thermometry technique based on the fluorescence decay rate of covalently attached fluorophores to extract the temperature within 2 nm of any oxide surface. We demonstrate precise spatial control of voltage dependent temperature profiles on the transistor surfaces. Our results introduce a new dimension to present sensing systems by enabling dual purpose silicon transistor-heaters that serve both as field effect sensors as well as temperature controllers that could perform localized bio-chemical reactions in Lab on Chip applications. PMID:19967115

Elibol, Oguz H.; Reddy, Bobby; Nair, Pradeep R.; Dorvel, Brian; Butler, Felice; Ahsan, Zahab; Bergstrom, Donald E.; Alam, Muhammad A.; Bashir, Rashid

2010-01-01

25

A robust and well shielded thermal conductivity device for low temperature measurements.  

PubMed

We present a compact mechanically robust thermal conductivity measurement apparatus for measurements at low temperatures (<1 K) and high magnetic fields on small high-purity single crystal samples. A high-conductivity copper box is used to enclose the sample and all the components. The box provides protection for the thermometers, heater, and most importantly the sample increasing the portability of the mount. In addition to physical protection, the copper box is also effective at shielding radio frequency electromagnetic interference and thermal radiation, which is essential for low temperature measurements. A printed circuit board in conjunction with a braided ribbon cable is used to organize the delicate wiring and provide mechanical robustness. PMID:24784624

Toews, W H; Hill, R W

2014-04-01

26

Measuring Temperature  

NSDL National Science Digital Library

This is a lesson about measuring temperature. Learners will apply their knowledge of how temperature affects matter to understand how a thermometer works. They then read about the history of the thermometer and the temperature scales that make the information from the thermometer meaningful. The lesson models scientific inquiry using the 5E instructional model and includes teacher notes, prerequisite concepts, common misconceptions, student journal and reading. This is lesson 6 in the Astro-Venture Astronomy Unit. The lessons are designed for educators to use in conjunction with the Astro-Venture multimedia modules.

27

Portable emittance measurement device  

SciTech Connect

In Institute for Theoretical and Experimental Physics (ITEP) the portable emittance measurements device is developed. It provides emittance measurements both with ''pepper-pot'' and ''two slits'' methods. Depending on the method of measurements, either slits or pepper-pot mask with scintillator are mounted on the two activators and are installed in two standard Balzer's cross chamber with CF-100 flanges. To match the angle resolution for measured beam, the length of the stainless steel pipe between two crosses changes is adjusted. The description of the device and results of emittance measurements at the ITEP ion source test bench are presented.

Liakin, D.; Seleznev, D.; Orlov, A.; Kuibeda, R.; Kropachev, G.; Kulevoy, T.; Yakushin, P. [Institute for Theoretical and Experimental Physics, Moscow 117218 (Russian Federation)

2010-02-15

28

Temperature measurement  

MedlinePLUS

... mouth for 3 minutes or until the device beeps. Rectum -- this method is for infants and small ... Remove after 3 minutes or when the device beeps. Armpit -- place the thermometer in the armpit, with ...

29

Fluid velocity measuring device  

NASA Technical Reports Server (NTRS)

A fluid velocity measuring device is described which, when placed in a freestream fluid flow, causes vortices to be formed at a frequency proportional to the flow rate of the fluid. Sensors on the device generate electric signals with frequency proportional to the rate of vortex creation and with relative mean amplitudes indicative of fluid flow direction. Electric circuitry translates the electric signals into indications of fluid speed and direction.

Thomas, D. F., Jr.; Williams, L. A., Jr. (inventors)

1978-01-01

30

High temperature superconductor micro-superconducting-quantum-interference-device magnetometer for magnetization measurement of a microscale magnet  

SciTech Connect

We have developed a high temperature superconductor (HTS) micrometer-sized dc superconducting quantum interference device (SQUID) magnetometer for high field and high temperature operation. It was fabricated from YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} of 92 nm in thickness with photolithography techniques to have a hole of 4x9 {mu}m{sup 2} and 2 {mu}m wide grain boundary Josephson junctions. Combined with a three dimensional magnetic field coil system, the modulation patterns of critical current I{sub c} were observed for three different field directions. They were successfully used to measure the magnetic properties of a molecular ferrimagnetic microcrystal (23x17x13 {mu}m{sup 3}), [Mn{sub 2}(H{sub 2}O){sub 2}(CH{sub 3}COO)][W(CN){sub 8}]{center_dot}2H{sub 2}O. The magnetization curve was obtained in magnetic field up to 0.12 T between 30 and 70 K. This is the first to measure the anisotropy of hysteresis curve in the field above 0.1 T with an accuracy of 10{sup -12} J T{sup -1} (10{sup -9} emu) with a HTS micro-SQUID magnetometer.

Takeda, Keiji [Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa-shi, Chiba 277-8581 (Japan); Department of Chemistry, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan); CREST, JST, Kawaguchi-shi, Saitama 332-0012 (Japan); Mori, Hatsumi [Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa-shi, Chiba 277-8581 (Japan); CREST, JST, Kawaguchi-shi, Saitama 332-0012 (Japan); Yamaguchi, Akira; Ishimoto, Hidehiko [Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa-shi, Chiba 277-8581 (Japan); Nakamura, Takayoshi [CREST, JST, Kawaguchi-shi, Saitama 332-0012 (Japan); Research Institute for Electronic Science, Hokkaido University, Kita 12 Nishi 6, Sapporo-shi, Hokkaido 060-0812 (Japan); Kuriki, Shinya [Research Institute for Electronic Science, Hokkaido University, Kita 12 Nishi 6, Sapporo-shi, Hokkaido 060-0812 (Japan); Hozumi, Toshiya; Ohkoshi, Shin-ichi [Department of Chemistry, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033 (Japan)

2008-03-15

31

Solid state device for two-wire downhole temperature measurement as a function of current. Final performance technical report  

SciTech Connect

Several metals systems were reviewed for their potential to act as resistive temperature devices. Platinum metal was selected as the metal of choice. Platinum was plated onto 5 mil copper wire, and then subsequently coated with Accusol's proprietary ceramic coating. The copper was etched out in an attempt to make a pure platinum, high resistive, resistive-temperature device. The platinum plating on the wire cracked during processing, resulting in a discontinuous layer of platinum, and the element could not be formed in this way.

Anderson, Roger; Anderson, David

2002-01-15

32

Inducer Hydrodynamic Load Measurement Devices  

NASA Technical Reports Server (NTRS)

Marshall Space Flight Center (MSFC) has demonstrated two measurement devices for sensing and resolving the hydrodynamic loads on fluid machinery. The first - a derivative of the six-component wind tunnel balance - senses the forces and moments on the rotating device through a weakened shaft section instrumented with a series of strain gauges. This rotating balance was designed to directly measure the steady and unsteady hydrodynamic loads on an inducer, thereby defining both the amplitude and frequency content associated with operating in various cavitation modes. The second device - a high frequency response pressure transducer surface mounted on a rotating component - was merely an extension of existing technology for application in water. MSFC has recently completed experimental evaluations of both the rotating balance and surface-mount transducers in a water test loop. The measurement bandwidth of the rotating balance was severely limited by the relative flexibility of the device itself, resulting in an unexpectedly low structural bending mode and invalidating the higher-frequency response data. Despite these limitations, measurements confirmed that the integrated loads on the four-bladed inducer respond to both cavitation intensity and cavitation phenomena. Likewise, the surface-mount pressure transducers were subjected to a range of temperatures and flow conditions in a non-rotating environment to record bias shifts and transfer functions between the transducers and a reference device. The pressure transducer static performance was within manufacturer's specifications and dynamic response accurately followed that of the reference.

Skelley, Stephen E.; Zoladz, Thomas F.; Turner, Jim (Technical Monitor)

2002-01-01

33

Inducer Hydrodynamic Load Measurement Devices  

NASA Technical Reports Server (NTRS)

Marshall Space Flight Center (MSFC) has demonstrated two measurement devices for sensing and resolving the hydrodynamic loads on fluid machinery. The first - a derivative of the six component wind tunnel balance - senses the forces and moments on the rotating device through a weakened shaft section instrumented with a series of strain gauges. This "rotating balance" was designed to directly measure the steady and unsteady hydrodynamic loads on an inducer, thereby defining both the amplitude and frequency content associated with operating in various cavitation modes. The second device - a high frequency response pressure transducer surface mounted on a rotating component - was merely an extension of existing technology for application in water. MSFC has recently completed experimental evaluations of both the rotating balance and surface-mount transducers in a water test loop. The measurement bandwidth of the rotating balance was severely limited by the relative flexibility of the device itself, resulting in an unexpectedly low structural bending mode and invalidating the higher frequency response data. Despite these limitations, measurements confirmed that the integrated loads on the four-bladed inducer respond to both cavitation intensity and cavitation phenomena. Likewise, the surface-mount pressure transducers were subjected to a range of temperatures and flow conditions in a non-rotating environment to record bias shifts and transfer functions between the transducers and a reference device. The pressure transducer static performance was within manufacturer's specifications and dynamic response accurately followed that of the reference.

Skelley, Stephen E.; Zoladz, Thomas F.

2002-01-01

34

Capacitance measuring device  

DOEpatents

A capacitance measuring circuit is provided in which an unknown capacitance is measured by comparing the charge stored in the unknown capacitor with that stored in a known capacitance. Equal and opposite voltages are repetitively simultaneously switched onto the capacitors through an electronic switch driven by a pulse generator to charge the capacitors during the ''on'' portion of the cycle. The stored charge is compared by summing discharge currents flowing through matched resistors at the input of a current sensor during the ''off'' portion of the switching cycle. The net current measured is thus proportional to the difference in value of the two capacitances. The circuit is capable of providing much needed accuracy and stability to a great variety of capacitance-based measurement devices at a relatively low cost.

Andrews, W.H. Jr.

1984-08-01

35

A Comparison between Conductive and Infrared Devices for Measuring Mean Skin Temperature at Rest, during Exercise in the Heat, and Recovery  

PubMed Central

Purpose Skin temperature assessment has historically been undertaken with conductive devices affixed to the skin. With the development of technology, infrared devices are increasingly utilised in the measurement of skin temperature. Therefore, our purpose was to evaluate the agreement between four skin temperature devices at rest, during exercise in the heat, and recovery. Methods Mean skin temperature (T-sk) was assessed in thirty healthy males during 30 min rest (24.0 ± 1.2°C, 56 ± 8%), 30 min cycle in the heat (38.0 ± 0.5°C, 41 ± 2%), and 45 min recovery (24.0 ± 1.3°C, 56 ± 9%). T-sk was assessed at four sites using two conductive devices (thermistors, iButtons) and two infrared devices (infrared thermometer, infrared camera). Results Bland–Altman plots demonstrated mean bias ± limits of agreement between the thermistors and iButtons as follows (rest, exercise, recovery): -0.01 ± 0.04, 0.26 ± 0.85, -0.37 ± 0.98°C; thermistors and infrared thermometer: 0.34 ± 0.44, -0.44 ± 1.23, -1.04 ± 1.75°C; thermistors and infrared camera (rest, recovery): 0.83 ± 0.77, 1.88 ± 1.87°C. Pairwise comparisons of T-sk found significant differences (p < 0.05) between thermistors and both infrared devices during resting conditions, and significant differences between the thermistors and all other devices tested during exercise in the heat and recovery. Conclusions These results indicate poor agreement between conductive and infrared devices at rest, during exercise in the heat, and subsequent recovery. Infrared devices may not be suitable for monitoring T-sk in the presence of, or following, metabolic and environmental induced heat stress. PMID:25659140

Bach, Aaron J. E.; Stewart, Ian B.; Disher, Alice E.; Costello, Joseph T.

2015-01-01

36

The Design and Realization of on-line Measuring Device of Busbar Temperature Rise for HV Switch Board  

Microsoft Academic Search

Because the buses inside HV switchgear cabinet are under high voltage condition, the very high voltage between the contacts of high-voltage switch or between high-voltage buses makes the direct measurement of its temperature a very difficult problem which has not been solved in practice so far. For these reasons, a method to measure the temperature of the bus-bar for switchgear

Zeng Linsuo; Wang Maojun

2006-01-01

37

Temperature monitoring device and thermocouple assembly therefor  

DOEpatents

A temperature monitoring device for measuring the temperature at a surface of a body, composed of: at least one first thermocouple and a second thermocouple; support members supporting the thermocouples for placing the first thermocouple in contact with the body surface and for maintaining the second thermocouple at a defined spacing from the body surface; and a calculating circuit connected to the thermocouples for receiving individual signals each representative of the temperature reading produced by a respective one of the first and second thermocouples and for producing a corrected temperature signal having a value which represents the temperature of the body surface and is a function of the difference between the temperature reading produced by the first thermocouple and a selected fraction of the temperature reading provided by the second thermocouple.

Grimm, Noel P. (Monroeville, PA); Bauer, Frank I. (Perry Township, Lawrence County, PA); Bengel, Thomas G. (Plum Boro, PA); Kothmann, Richard E. (Churchill Boro, PA); Mavretish, Robert S. (New Stanton, PA); Miller, Phillip E. (Greensburg, PA); Nath, Raymond J. (Murrysville, PA); Salton, Robert B. (Plum Boro, PA)

1991-01-01

38

A comparison of globe, wet and dry temperature and humidity measuring devices available for heat stress assessment  

Microsoft Academic Search

Various controlled and ambient tests were undertaken to evaluate the performance of a variety of digital heat stress monitors, psychrometers and simpler temperature\\/relative humidity data loggers that measure, or determine, such parameters as: dry-bulb, natural wet-bulb, psychrometric wet-bulb and globe temperatures. In this comparison, funded by the Deep Mining Research Consortium, it has been found that all the instruments can

S. Hardcastle; K. Butler

39

Measurements of ion temperature and flow of pulsed plasmas produced by a magnetized coaxial plasma gun device using an ion Doppler spectrometer  

NASA Astrophysics Data System (ADS)

It is important to know surface damage characteristics of plasma-facing component materials during transient heat and particle loads such as type I ELMs. A magnetized coaxial plasma gun (MCPG) device has been used as transient heat and particle source in ELM simulation experiments. Characteristics of pulsed plasmas produced by the MCPG device play an important role for the plasma material interaction. In this study, ion temperature and flow velocity of pulsed He plasmas were measured by an ion Doppler spectrometer (IDS). The IDS system consists of a light collection system including optical fibers, 1m-spectrometer and a 16 channel photomultiplier tube (PMT) detector. The IDS system measures the width and Doppler shift of HeII (468.58 nm) emission line with the time resolution of 1 ?s. The Doppler broadened and shifted spectra were measured with 45 and 135 degree angles with respect to the plasmoid traveling direction. The observed emission line profile was represented by sum of two Gaussian components to determine the temperature and flow velocity. The minor component at around the wavelength of zero-velocity was produced by the stationary plasma. As the results, the ion velocity and temperature were 68 km/s and 19 eV, respectively. Thus, the He ion flow energy is 97 eV. The observed flow velocity agrees with that measured by a time of flight technique.

Kitagawa, Y.; Sakuma, I.; Iwamoto, D.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

2012-10-01

40

A new developed velocity of sound measurement device for characterization of multi-component gas mixtures under elevated temperatures and pressures  

NASA Astrophysics Data System (ADS)

Inline process control by measurement of velocity of sound of fluids is a direct and comprehensive technique [J. D. N. Cheeke and Z. Wang, "Acoustic wave gas sensors," Sens. Actuators B 59, 146-153 (1999); J. W. Grate, S. J. Martin, and R. M. White, "Acoustic wave microsensors," Anal. Chem. 65, 1868 (1993)]. Depending on the varying conditions of measuring fluid(s), temperatures and pressures, it is a challenging task to find the best possible acoustic setup. Taking this background into account, a velocity of sound measurement device for temperatures up to 475 K and pressures up to 24 MPa was designed and assembled that is to be used for testing different resonator types. Two bulk acoustic wave resonators out of the commonly used lead zirconatetitanate compound (PZT) were tested at different test fluids under temperatures up to 423.15 K and pressures up to 24 MPa [S. Gebhardt, L. Seffner, F. Schlenkirch, and A. Schönecker, "PZT thick films for sensor and actuator applications," J. Eur. Ceram. Soc. 27, 4177-4180 (2007)]. Initially the pure gases methane, ethane, carbon dioxide, nitrogen, and helium were measured, followed by multi-component gas mixtures. Beside methane-based binary and ternary gas mixtures, a quaternary gas mixture comprising methane, ethane, carbon dioxide, and helium was analyzed. Results for all measurement fluids in a broad temperature and pressure range show a relative deviation to theoretical values derived from GERG-2008 smaller than 0.5%.

Seibel, C.; Suedmeyer, J.; Fieback, T. M.

2014-07-01

41

Evaluation and improvement in the accuracy of a charge-coupled-device-based pyrometer for temperature field measurements of continuous casting billets.  

PubMed

This paper presents a radiometric high-temperature field measurement model based on a charge-coupled-device (CCD). According to the model, an intelligent CCD pyrometer with a digital signal processor as the core is developed and its non-uniformity correction algorithm for reducing the differences in accuracy between individual pixel sensors is established. By means of self-adaptive adjustment for the light-integration time, the dynamic range of the CCD is extended and its accuracy in low-temperature range is improved. The non-uniformity correction algorithm effectively reduces the accuracy differences between different pixel sensors. The performance of the system is evaluated through a blackbody furnace and an integrating sphere, the results of which show that the dynamic range of 400 K is obtained and the accuracy in low temperature range is increased by 7 times compared with the traditional method based on the fixed light-integration time. In addition, the differences of accuracy between the on-axis pixel and the most peripheral pixels are decreased from 19.1 K to 2.8 K. Therefore, this CCD pyrometer ensures that the measuring results of all pixels tend to be equal-accuracy distribution across the entire measuring ranges. This pyrometric system has been successfully applied to the temperature field measurements in continuous casting billets. PMID:23822369

Bai, Haicheng; Xie, Zhi; Zhang, Yuzhong; Hu, Zhenwei

2013-06-01

42

TEMPERATURE SAFETY DEVICE FOR AQUATIC LABORATORY SYSTEMS  

EPA Science Inventory

The temperature safety device described here will protect aquatic organisms in experiments or in rearing and holding facilities by stopping water flow when set temperatures are exceeded. The device consists of switches constructed from aquarium heaters that are activated by exces...

43

Temperature controller for hyperthermia devices  

NASA Technical Reports Server (NTRS)

Temperature controller monitors and controls temperature in local region of tumor. Medical grade thermocouples are inserted in or near tumor, controller pulse modulates radio frequency diathermy power source to maintain temperature within 0.2 C. System may be extended to control diathermy of more than one tumor or patient.

Couch, R. H.; Hearn, C. P.; Williams, J. B.

1980-01-01

44

Edge turbulence measurements in toroidal fusion devices  

Microsoft Academic Search

This paper reviews measurements of edge plasma turbulence in toroidal magnetic fusion devices with an emphasis on recent results in tokamaks. The dominant feature of edge turbulence is a high level of broadband density fluctuations with a relative amplitude deltan\\/n ~ 5 100%, accompanied by large potential and electron temperature fluctuations. The frequency range of this turbulence is ~10 kHz

S. J. Zweben; J. A. Boedo; O. Grulke; C. Hidalgo; B. La Bombard; R. J. Maqueda; P. Scarin; J. L. Terry

2007-01-01

45

Temperature-controlled fluidic device A concept  

NASA Technical Reports Server (NTRS)

Symmetrical fluidic device directly converts electrical signals to mechanical signals in the form of a fluid-flow parameter. This device eliminates or reduces effects of all undesirable parameters on the departure angle, leaving it a function of the controlled wall and jet temperatures.

Rehsteiner, F. H.

1970-01-01

46

Development of a Low-Temperature Insert for Precise Magnetization Measurement below T = 2 K with a Superconducting Quantum Interference Device Magnetometer  

NASA Astrophysics Data System (ADS)

We have developed a 9-mm-diameter 3He insert for precise magnetization measurements below T = 2 K that is attachable to a commercial superconducting quantum interference device magnetometer. The insert is made from a thin-walled stainless steel pipe with an inner diameter of 6.2 mm, which determines the maximum sample size. 3He gas is condensed in the pipe, which is liquefied by 4He gas at T ?1.8 K generated by the magnetometer via the heat exchanger of a Cu vacuum jacket with an outer diameter of 8.6 mm soldered to the stainless steel pipe. The temperature of the insert is decreased to T ?0.5 K by evacuating liquid 3He using a rotary pump and then to T = 0.36 K with a sorption pump. From the diamagnetization signal of a superconducting Al chip with a mass below 0.1 mg, the magnetization resolution with the insert is confirmed to be less than 10-7 emu. To examine the performance of the insert, we measured the temperature dependence of the magnetic susceptibility and magnetization for Pr0.6La0.4Ag2In down to T = 0.4 K.

Sato, Yoshiaki; Makiyama, Shun; Sakamoto, Yasutaka; Hasuo, Tadahiko; Inagaki, Yuji; Fujiwara, Tetsuya; Suzuki, Hiroyuki S.; Matsubayashi, Kazuyuki; Uwatoko, Yoshiya; Kawae, Tatsuya

2013-10-01

47

Temperature measurement and control  

Microsoft Academic Search

Several factors in temperature measurement that can affect the precision of melting points and phase-change phenomena are\\u000a discussed. In many cases, critical errors may arise in the measurement and control of temperatures due to incorrect placement\\u000a and\\/or interpretation of the output of temperature sensors in the various system types that are in current use. Advantages\\u000a can be obtained by using

R. P. Tye; R. L. Gardner; A. Maesono

1993-01-01

48

Finger-Circumference-Measuring Device  

NASA Technical Reports Server (NTRS)

Easy-to-use device quickly measures circumference of finger (including thumb) on human hand. Includes polytetrafluoroethylene band 1/8 in. wide, bent into loop and attached to tab that slides on scale graduated in millimeters. Sliding tab preloaded with constant-force tension spring, which pulls tab toward closure of loop. Designed to facilitate measurements at various points along fingers to obtain data for studies of volumetric changes of fingers in microgravity. Also used in normal Earth gravity studies of growth and in assessment of diseases like arthritis.

Le, Suy

1995-01-01

49

Temperature Measurement with Phidgets  

NSDL National Science Digital Library

The EJS Temperature Measurement with Phidget collects data from a Phidget 1048 Temperature Sensor and Thermocouple. The Phdiget driver must be installed. The instructors are for an introductory physics lab on using computer controls transducers. Once Ejs is installed, right-clicking within the plot and selecting âOpen Ejs Modelâ from the pop-up menu item allows for editing of the model and, in particular, editing the serial number of the Hardware (as described in the lab instructions). The Temperature Measurement model was created using the Easy Java Simulations (Ejs) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_PhidgetTemperatureExample.jar file will run the program if Java is installed. Ejs is a part of the Open Source Physics Project and is designed to make it easier to access, modify, and generate computer models.

Cox, Anne; Franciscouembre

2014-08-26

50

Temperature standards, what and where: resources for effective temperature measurements  

SciTech Connect

Many standards have been published to describe devices, methods, and other topics. How they are developed and by whom are briefly described, and an attempt is made to extract most of those relating to temperature measurements. A directory of temperature standards and their sources is provided.

Johnston, W.W. Jr.

1982-01-01

51

Passive wireless strain and temperature sensors based on SAW devices  

Microsoft Academic Search

This work gives an overview of existing approaches to wireless strain and temperature measurements that employ passive sensors based on two types of SAW devices; reflective delay lines and one-port resonators. The performance of these two types of sensors is compared from the point of view of the achieved sensitivity, resolution, read range, interrogation time and power. A quantitative comparison

Victor Kalinin

2004-01-01

52

On quantum interferometric measurements of temperature  

E-print Network

We provide a detailed description of the interferometric thermometer, which is a device that estimates the temperature of a sample from measurements of the optical phase. For the first time, we rigorously analyze the operation of such a device by studying the interaction of the optical probe system with a heated sample. We find that this approach to thermometry is capable of measuring the temperature of a sample in the nK regime. Furthermore, we compare the theoretical precision of interferometric thermometers with the precision offered by the idealized pyrometers, which infer the temperature from a measurement of the total thermal radiation emitted by the sample.

Marcin Jarzyna; Marcin Zwierz

2014-12-17

53

Nonvisual Adaptive Devices for Measuring Insulin.  

ERIC Educational Resources Information Center

This article presents information on nonvisual adaptive devices for measuring insulin and offers some suggestions for rehabilitation professionals who instruct and supervise clients with diabetes and visual impairment in the use of these devices. (Author)

Cleary, M. E.; Hamilton, J. E.

1993-01-01

54

Design parameter evaluation of a metal recoated Fiber Bragg Grating sensors for measurement of cryogenic temperature or stress in superconducting devices  

Microsoft Academic Search

There are plenty of complex physical phenomena which remain to be studied and verified experimentally for building an optimized superconducting magnet. The main problem for experimental validations is due to the unavailability of suitable sensors. This paper proposes a Fiber Bragg Gratings (FBG) sensor for this purpose which allows access to the local temperature\\/stress state. To measure the low temperature

R. Rajinikumar; M. Süßer; K. G. Narayankhedkar; G. Krieg; M. D. Atrey

2009-01-01

55

A Portable, High Resolution, Surface Measurement Device  

NASA Technical Reports Server (NTRS)

A high resolution, portable, surface measurement device has been demonstrated to provide micron-resolution topographical plots. This device was specifically developed to allow in-situ measurements of defects on the Space Shuttle Orbiter windows, but is versatile enough to be used on a wide variety of surfaces. This paper discusses the choice of an optical sensor and then the decisions required to convert a lab bench optical measurement device into an ergonomic portable system. The necessary trade-offs between performance and portability are presented along with a description of the device developed to measure Orbiter window defects.

Ihlefeld, Curtis M.; Burns, Bradley M.; Youngquist, Robert C.

2012-01-01

56

Design parameter evaluation of a metal recoated Fiber Bragg Grating sensors for measurement of cryogenic temperature or stress in superconducting devices  

NASA Astrophysics Data System (ADS)

There are plenty of complex physical phenomena which remain to be studied and verified experimentally for building an optimized superconducting magnet. The main problem for experimental validations is due to the unavailability of suitable sensors. This paper proposes a Fiber Bragg Gratings (FBG) sensor for this purpose which allows access to the local temperature/stress state. To measure the low temperature (20 K), FBG can be recoated with materials having high thermal expansion coefficient (HTCE). This can induce a thermal stress for a temperature change, which in turn increases the sensitivity of the sensor. The performance of such sensors has been experimentally studied and reported in earlier paper [Rajinikumar R, Suesser M, Narayankhedkar KG, Krieg G, Atrey MD. Performance evaluation of metallic coated Fiber Bragg Grating sensors for sensing cryogenic temperature. Cryogenics 2008;48:142-7]. This paper aims at evaluation and determination of different design parameters like coating materials, coating thickness, grating period and the grating length for design of better performance FBG sensor for low temperature/stress measurements.

Rajinikumar, R.; Süßer, M.; Narayankhedkar, K. G.; Krieg, G.; Atrey, M. D.

2009-05-01

57

Device and method for detecting sulfur dioxide at high temperatures  

DOEpatents

The present invention relates to a method for selectively detecting and/or measuring gaseous SO.sub.2 at a temperature of at least 500.degree. C., the method involving: (i) providing a SO.sub.2-detecting device including an oxygen ion-conducting substrate having on its surface at least three electrodes comprising a first, second, and third electrode; (ii) driving a starting current of specified magnitude and temporal variation between the first and second electrodes; (iii) contacting the SO.sub.2-detecting device with the SO.sub.2-containing sample while maintaining the magnitude and any temporal variation of the starting current, wherein said SO.sub.2-containing sample causes a change in the electrical conductance of said device; and (iv) detecting the change in electrical conductance of the device based on measuring an electrical property related to or indicative of the conductance of the device between the first and third electrodes, or between the second and third electrodes, and detecting SO.sub.2 in the SO.sub.2-containing sample based on the measured change in electrical conductance.

West, David L. (Oak Ridge, TN); Montgomery, Frederick C. (Oak Ridge, TN); Armstrong, Timothy R. (Clinton, TN)

2011-11-01

58

Introducing Temperature Measurement  

NSDL National Science Digital Library

In this activity, students will learn how to read a Celsius-scale thermometer, associate weather conditions and seasons with Celsius temperature ranges, and keep a record of temperature. Students will read the Celsius temperature each day and discuss how given temperatures "feel". They record the temperature by using a string of beads and a chart.

59

21 CFR 864.5950 - Blood volume measuring device.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Blood volume measuring device. 864.5950...Semi-Automated Hematology Devices § 864.5950 Blood volume measuring device. (a) Identification. A blood volume measuring device is a...

2011-04-01

60

21 CFR 864.5950 - Blood volume measuring device.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Blood volume measuring device. 864.5950...Semi-Automated Hematology Devices § 864.5950 Blood volume measuring device. (a) Identification. A blood volume measuring device is a...

2013-04-01

61

21 CFR 864.5950 - Blood volume measuring device.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Blood volume measuring device. 864.5950...Semi-Automated Hematology Devices § 864.5950 Blood volume measuring device. (a) Identification. A blood volume measuring device is a...

2014-04-01

62

21 CFR 864.5950 - Blood volume measuring device.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Blood volume measuring device. 864.5950...Semi-Automated Hematology Devices § 864.5950 Blood volume measuring device. (a) Identification. A blood volume measuring device is a...

2012-04-01

63

21 CFR 864.5950 - Blood volume measuring device.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Blood volume measuring device. 864.5950...Semi-Automated Hematology Devices § 864.5950 Blood volume measuring device. (a) Identification. A blood volume measuring device is a...

2010-04-01

64

21 CFR 882.1540 - Galvanic skin response measurement device.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Galvanic skin response measurement device. 882.1540...Diagnostic Devices § 882.1540 Galvanic skin response measurement device. (a) Identification. A galvanic skin response measurement device is a...

2010-04-01

65

21 CFR 886.1450 - Corneal radius measuring device.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Corneal radius measuring device. 886.1450... Diagnostic Devices § 886.1450 Corneal radius measuring device. (a) Identification. A corneal radius measuring device is an...

2010-04-01

66

21 CFR 882.1550 - Nerve conduction velocity measurement device.  

Code of Federal Regulations, 2011 CFR

... 2011-04-01 false Nerve conduction velocity measurement device. 882...Diagnostic Devices § 882.1550 Nerve conduction velocity measurement device. (a) Identification. A nerve conduction velocity measurement device is...

2011-04-01

67

21 CFR 882.1550 - Nerve conduction velocity measurement device.  

Code of Federal Regulations, 2012 CFR

... 2012-04-01 false Nerve conduction velocity measurement device. 882...Diagnostic Devices § 882.1550 Nerve conduction velocity measurement device. (a) Identification. A nerve conduction velocity measurement device is...

2012-04-01

68

21 CFR 882.1550 - Nerve conduction velocity measurement device.  

Code of Federal Regulations, 2013 CFR

... 2013-04-01 false Nerve conduction velocity measurement device. 882...Diagnostic Devices § 882.1550 Nerve conduction velocity measurement device. (a) Identification. A nerve conduction velocity measurement device is...

2013-04-01

69

21 CFR 882.1550 - Nerve conduction velocity measurement device.  

Code of Federal Regulations, 2014 CFR

... 2014-04-01 false Nerve conduction velocity measurement device. 882...Diagnostic Devices § 882.1550 Nerve conduction velocity measurement device. (a) Identification. A nerve conduction velocity measurement device is...

2014-04-01

70

PORTABLE DEVICE FOR MEASURING SEDIMENT RESUSPENSION  

EPA Science Inventory

A portable device for measuring sediment resuspension has been developed. he device consists of a cylindrical chamber inside of which a horizontal grid oscillates vertically. he sediments whose properties are to be determined are placed at the bottom of the chamber with water ove...

71

Line spectrum and ion temperature measurements from tungsten ions at low ionization stages in large helical device based on vacuum ultraviolet spectroscopy in wavelength range of 500-2200 Åa)  

NASA Astrophysics Data System (ADS)

Vacuum ultraviolet spectra of emissions released from tungsten ions at lower ionization stages were measured in the Large Helical Device (LHD) in the wavelength range of 500-2200 Å using a 3 m normal incidence spectrometer. Tungsten ions were distributed in the LHD plasma by injecting a pellet consisting of a small piece of tungsten metal and polyethylene tube. Many lines having different wavelengths from intrinsic impurity ions were observed just after the tungsten pellet injection. Doppler broadening of a tungsten candidate line was successfully measured and the ion temperature was obtained.

Oishi, T.; Morita, S.; Huang, X. L.; Zhang, H. M.; Goto, M.

2014-11-01

72

Validity and Reliability of Devices That Assess Body Temperature During Indoor Exercise in the Heat  

PubMed Central

Context: When assessing exercise hyperthermia outdoors, the validity of certain commonly used body temperature measuring devices has been questioned. A controlled laboratory environment is generally less influenced by environmental factors (eg, ambient temperature, solar radiation, wind) than an outdoor setting. The validity of these temperature measuring devices in a controlled environment may be more acceptable. Objective: To assess the validity and reliability of commonly used temperature devices compared with rectal temperature in individuals exercising in a controlled, high environmental temperature indoor setting and then resting in a cool environment. Design: Time series study. Setting: Laboratory environmental chamber (temperature ?=? 36.4 ± 1.2°C [97.5 ± 2.16°F], relative humidity ?=? 52%) and cool laboratory (temperature ?=? approximately 23.3°C [74.0°F], relative humidity ?=? 40%). Patients or Other Participants: Fifteen males and 10 females. Intervention(s): Rectal, gastrointestinal, forehead, oral, aural, temporal, and axillary temperatures were measured with commonly used temperature devices. Temperature was measured before and 20 minutes after entering the environmental chamber, every 30 minutes during a 90-minute treadmill walk in the heat, and every 20 minutes during a 60-minute rest in mild conditions. Device validity and reliability were assessed with various statistical measures to compare the measurements using each device with rectal temperature. A device was considered invalid if the mean bias (average difference between rectal and device temperatures) was more than ±0.27°C (±0.50°F). Main Outcome Measure(s): Measured temperature from each device (mean and across time). Results: The following devices provided invalid estimates of rectal temperature: forehead sticker (0.29°C [0.52°F]), oral temperature using an inexpensive device (?1.13°C [?2.03°F]), temporal temperature measured according to the instruction manual (?0.87°C [?1.56°F]), temporal temperature using a modified technique (?0.63°C [?1.13°F]), oral temperature using an expensive device (?0.86°C, [?1.55°F]), aural temperature (?0.67°C, [?1.20°F]), axillary temperature using an inexpensive device (?1.25°C, [?2.24°F]), and axillary temperature using an expensive device (?0.94°F [?1.70°F]). Measurement of intestinal temperature (mean bias of ?0.02°C [?0.03°F]) was the only device considered valid. Devices measured in succession (intestinal, forehead, temporal, and aural) showed acceptable reliability (all had a mean bias ?=? 0.09°C [0.16°F] and r ? 0.94]). Conclusions: Even during laboratory exercise in a controlled environment, devices used to measure forehead, temporal, oral, aural, and axillary body sites did not provide valid estimates of rectal temperature. Only intestinal temperature measurement met the criterion. Therefore, we recommend that rectal or intestinal temperature be used to assess hyperthermia in individuals exercising indoors in the heat. PMID:19295956

Ganio, Matthew S; Brown, Christopher M; Casa, Douglas J; Becker, Shannon M; Yeargin, Susan W; McDermott, Brendon P; Boots, Lindsay M; Boyd, Paul W; Armstrong, Lawrence E; Maresh, Carl M

2009-01-01

73

Going Places No Infrared Temperature Devices Have Gone Before  

NASA Technical Reports Server (NTRS)

Exergen's IRt/c is a self-powered sensor that matches a thermocouple within specified temperature ranges and provides a predictable and repeatable signal outside of this specified range. Possessing an extremely fast time constant, the infrared technology allows users to measure product temperature without touching the product. The IRt/c uses a device called a thermopile to measure temperature and generate current. Traditionally, these devices are not available in a size that would be compatible with the Exergen IRt/c, based on NASA s quarterinch specifications. After going through five circuit designs to find a thermopile that would suit the IRt/c design and match the signal needed for output, Exergen maintains that it developed a model that totaled just 20 percent of the volume of the previous smallest detector in the world. Following completion of the project with Glenn, Exergen continued development of the IRt/c for other customers, spinning off a new product line called the micro IRt/c. This latest development has broadened applications for industries that previously could not use infrared thermometers due to size constraints. The first commercial use of the micro IRt/c involved an original equipment manufacturer that makes laminating machinery consisting of heated rollers in very tight spots. Accurate temperature measurement for this application requires close proximity to the heated rollers. With the micro IRt/c s 50-millisecond time constant, the manufacturer is able to gain closer access to the intended temperature targets for exact readings, thereby increasing productivity and staying ahead of competition.In a separate application, the infrared temperature sensor is being utilized for avalanche warnings in Switzerland. The IRt/c is mounted about 5 meters above the ground to measure the snow cover throughout the mountainous regions of the country.

2003-01-01

74

21 CFR 864.6400 - Hematocrit measuring device.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Hematocrit measuring device. 864.6400 Section 864.6400 Food and Drugs FOOD AND DRUG ADMINISTRATION...PATHOLOGY DEVICES Manual Hematology Devices § 864.6400 Hematocrit measuring device. (a)...

2010-04-01

75

Wireless device for monitoring the temperature - moisture regime in situ  

NASA Astrophysics Data System (ADS)

This contribution presents the wireless device for monitoring the temperature - moisture regime in situ. For the monitoring so called moisture sensor is used. Principle of moisture sensor is based on measuring the thermal conductivity. Moisture sensor has cylindrical shape with about 20 mm diameter and 20 mm length. It is made of porous material identical to the monitored object. The thermal conductivity is measured by hot-ball method. Hot-ball method is patented invention of the Institute of Physic SAS. It utilizes a small ball, diameter up to 2 mm, in which sensing elements are incorporated. The ball produces heat spreading into surrounding material, in our case into body of the moisture sensor. Temperature of the ball is measured simultaneously. Then change of the temperature, in steady state, is inversely proportional to the thermal conductivity. Such moisture sensor is inserted into monitored wall. Thermophysical properties of porous material are function of moisture. Moisture sensors are calibrated for dry and water saturated state. Whole the system is primarily intended to do long-term monitoring. Design of a new electronic device was needed for this innovative method. It covers all needed operations for measurement. For example energizing hot-ball sensor, measuring its response, storing the measured data and wireless data transmission. The unit is able to set parameters of measurement via wireless access as well. This contribution also includes the description of construction and another features of the wireless measurement system dedicated for this task. Possibilities and functionality of the system is demonstrated by actual monitoring of the tower of St. Martin's Cathedral in Bratislava. Correlations with surrounding meteorological conditions are presented. Some of them can be also measured by our system, right in the monitoring place.

Hudec, Ján; Štofanik, Vladimír; Vretenár, Viliam; Kubi?ár, ?udovít

2014-05-01

76

Transient (lightning) protection for electronic measurement devices  

SciTech Connect

Electronic measurement devices have become a major part of the oil and gas business today. All of these devices operate on an electrical voltage. Any voltage introduced into the system that is beyond the predetermined tolerance will cause degradation of performance or in some cases failure of the device. The extent of the damage depends upon the dielectric strength of the circuit in question and upon the available energy. As electronic measurement devices are further developed to incorporate more solid state circuitry and operate at lower voltage levels the more susceptible they become to transients. Along with transient protection, the user must also be concerned with intrinsic safety requirements of the device to be protected. The devices and techniques used to protect the equipment from transients do not, in all cases, guarantee the user certification for use in hazardous environments. As a note of reference, some of the techniques listed in this paper as examples would not be allowed in hazardous areas without the addition of other devices to further isolate or clamp the available energy to a safe level. In other words, as the industry moves forward to improve the overall accuracy of the measurement system and adds data availability via communication networks, the transient protection scheme must become more sophisticated.

Black, L.L. [Applied Automation/Hartmann & Braun, Bartlesville, OK (United States)

1995-12-01

77

An Innovative Flow-Measuring Device: Thermocouple Boundary Layer Rake  

NASA Technical Reports Server (NTRS)

An innovative flow-measuring device, a thermocouple boundary layer rake, was developed. The sensor detects the flow by using a thin-film thermocouple (TC) array to measure the temperature difference across a heater strip. The heater and TC arrays are microfabricated on a constant-thickness quartz strut with low heat conductivity. The device can measure the velocity profile well into the boundary layer, about 65 gm from the surface, which is almost four times closer to the surface than has been possible with the previously used total pressure tube.

Hwang, Danny P.; Fralick, Gustave C.; Martin, Lisa C.; Wrbanek, John D.; Blaha, Charles A.

2001-01-01

78

Electrolyte measurement device and measurement procedure  

DOEpatents

A method and apparatus for measuring the through-thickness resistance or conductance of a thin electrolyte is provided. The method and apparatus includes positioning a first source electrode on a first side of an electrolyte to be tested, positioning a second source electrode on a second side of the electrolyte, positioning a first sense electrode on the second side of the electrolyte, and positioning a second sense electrode on the first side of the electrolyte. current is then passed between the first and second source electrodes and the voltage between the first and second sense electrodes is measured.

Cooper, Kevin R. (Southern Pines, NC); Scribner, Louie L. (Southern Pines, NC)

2010-01-26

79

Electromagnetic pulse-induced current measurement device  

NASA Astrophysics Data System (ADS)

To develop safety guidelines for exposure to high fields associated with an electromagnetic pulse (EMP), it is necessary to devise techniques that would measure the peak current induced in the human body. The main focus of this project was to design, fabricate, and test a portable, self-contained stand-on device that would measure and hold the peak current and the integrated change Q. The design specifications of the EMP-Induced Current Measurement Device are as follows: rise time of the current pulse, 5 ns; peak current, 20-600 A; charge Q, 0-20 microcoulombs. The device uses a stand-on parallel-plate bilayer sensor and fast high-frequency circuit that are well-shielded against spurious responses to high incident fields. Since the polarity of the incident peak electric field of the EMP may be either positive or negative, the induced peak current can also be positive or negative. Therefore, the device is designed to respond to either of these polarities and measure and hold both the peak current and the integrated charge which are simultaneously displayed on two separate 3-1/2 digit displays. The prototype device has been preliminarily tested with the EMP's generated at the Air Force Weapons Laboratory (ALECS facility) at Kirtland AFB, New Mexico.

Gandhi, Om P.; Chen, Jin Y.

1991-08-01

80

21 CFR 886.4280 - Intraocular pressure measuring device.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Intraocular pressure measuring device. 886.4280 Section 886.4280 Food and...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4280...

2010-04-01

81

21 CFR 886.4280 - Intraocular pressure measuring device.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Intraocular pressure measuring device. 886.4280 Section 886.4280 Food and...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4280...

2011-04-01

82

21 CFR 886.4280 - Intraocular pressure measuring device.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Intraocular pressure measuring device. 886.4280 Section 886.4280 Food and...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4280...

2012-04-01

83

21 CFR 886.4280 - Intraocular pressure measuring device.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 false Intraocular pressure measuring device. 886.4280 Section 886.4280 Food and...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4280...

2014-04-01

84

21 CFR 886.1450 - Corneal radius measuring device.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Corneal radius measuring device. 886.1450 Section 886.1450 Food and...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1450 Corneal...

2012-04-01

85

21 CFR 886.1450 - Corneal radius measuring device.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Corneal radius measuring device. 886.1450 Section 886.1450 Food and...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1450 Corneal...

2011-04-01

86

21 CFR 886.4280 - Intraocular pressure measuring device.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Intraocular pressure measuring device. 886.4280 Section 886.4280 Food and...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4280...

2013-04-01

87

21 CFR 882.1550 - Nerve conduction velocity measurement device.  

Code of Federal Regulations, 2010 CFR

... false Nerve conduction velocity measurement device. 882.1550 Section 882.1550 Food and...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices §...

2010-04-01

88

21 CFR 886.1450 - Corneal radius measuring device.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Corneal radius measuring device. 886.1450 Section 886.1450 Food and...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Diagnostic Devices § 886.1450 Corneal...

2013-04-01

89

21 CFR 864.6400 - Hematocrit measuring device.  

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6400 Hematocrit measuring device. (a) Identification. A...

2013-04-01

90

High-Sensitivity Temperature Measurement  

ERIC Educational Resources Information Center

Describes a method of measuring small temperature differences that amount to a .01K, using an arrangement of a copper-constantan thermocouple, a microamplifier and a galvanometer, as an indirect way of measuring heat energy. (GA)

Leadstone, G. S.

1978-01-01

91

Temperature Measurements in the Magnetic Measurement Facility  

SciTech Connect

Several key LCLS undulator parameter values depend strongly on temperature primarily because of the permanent magnet material the undulators are constructed with. The undulators will be tuned to have specific parameter values in the Magnetic Measurement Facility (MMF). Consequently, it is necessary for the temperature of the MMF to remain fairly constant. Requirements on undulator temperature have been established. When in use, the undulator temperature will be in the range 20.0 {+-} 0.2 C. In the MMF, the undulator tuning will be done at 20.0 {+-} 0.1 C. For special studies, the MMF temperature set point can be changed to a value between 18 C and 23 C with stability of {+-}0.1 C. In order to ensure that the MMF temperature requirements are met, the MMF must have a system to measure temperatures. The accuracy of the MMF temperature measurement system must be better than the {+-}0.1 C undulator tuning temperature tolerance, and is taken to be {+-}0.01 C. The temperature measurement system for the MMF is under construction. It is similar to a prototype system we built two years ago in the Sector 10 alignment lab at SLAC. At that time, our goal was to measure the lab temperature to {+-}0.1 C. The system has worked well for two years and has maintained its accuracy. For the MMF system, we propose better sensors and a more extensive calibration program to achieve the factor of 10 increase in accuracy. In this note we describe the measurement system under construction. We motivate our choice of system components and give an overview of the system. Most of the software for the system has been written and will be discussed. We discuss error sources in temperature measurements and show how these errors have been dealt with. The calibration system is described in detail. All the LCLS undulators must be tuned in the Magnetic Measurement Facility at the same temperature to within {+-}0.1 C. In order to ensure this, we are building a system to measure the temperature of the undulators to {+-}0.01 C. This note describes the temperature measurement system under construction.

Wolf, Zachary

2010-12-13

92

Experimental measurement-device-independent entanglement detection.  

PubMed

Entanglement is one of the most puzzling features of quantum theory and of great importance for the new field of quantum information. The determination whether a given state is entangled or not is one of the most challenging open problems of the field. Here we report on the experimental demonstration of measurement-device-independent (MDI) entanglement detection using witness method for general two qubits photon polarization systems. In the MDI settings, there is no requirement to assume perfect implementations or neither to trust the measurement devices. This experimental demonstration can be generalized for the investigation of properties of quantum systems and for the realization of cryptography and communication protocols. PMID:25649664

Nawareg, Mohamed; Muhammad, Sadiq; Amselem, Elias; Bourennane, Mohamed

2015-01-01

93

Experimental Measurement-Device-Independent Entanglement Detection  

PubMed Central

Entanglement is one of the most puzzling features of quantum theory and of great importance for the new field of quantum information. The determination whether a given state is entangled or not is one of the most challenging open problems of the field. Here we report on the experimental demonstration of measurement-device-independent (MDI) entanglement detection using witness method for general two qubits photon polarization systems. In the MDI settings, there is no requirement to assume perfect implementations or neither to trust the measurement devices. This experimental demonstration can be generalized for the investigation of properties of quantum systems and for the realization of cryptography and communication protocols. PMID:25649664

Nawareg, Mohamed; Muhammad, Sadiq; Amselem, Elias; Bourennane, Mohamed

2015-01-01

94

Presentation of a new BRDF measurement device  

NASA Astrophysics Data System (ADS)

The bi-directional reflectance distribution function (BRDF) plays a major role to evaluate or analyze signals reflected by Earth in the solar spectrum. A BRDF measurement device that covers a large spectral and directional domain was recently developed by ONERA/DOTA. It was designed to allow both laboratory and outside measurements. Its main characteristics are a spectral domain: 0.42-0.95 micrometers ; a geometrical domain: 0-60 degrees for zenith angle, 0-180 degrees for azimuth; a maximum target size for nadir measurements: 22 cm. For a given zenith angle of the source, the BRDF device needs about seven minutes to take measurements for a viewing zenith angle varying from 0-60 degrees and relative azimuth angle varying from 0-180 degrees. The performances, imperfections and properties of each component of the measurement chain are studied. A part of the work was devoted to characterize precisely the source, and particularly the spatial variability of the irradiance at the target level, the temporal stability and the spectral profile of the lamp. Some of these imperfections are modeled and taken into account in corrections of BRDF measurements. Concerning the sensor, a calibration in wavelength was done. Measurements of bi- directional reflectance of which is well known. A software was developed to convert all the raw data acquired automatically into BRDF values. To illustrate measurements taken by this device, some results are also presented here. They are taken over sand and short grass, for different wavelengths and geometrical conditions.

Serrot, Gerard; Bodilis, Madeleine; Briottet, Xavier; Cosnefroy, Helene

1998-12-01

95

Measurement-device-independent quantum key distribution.  

PubMed

How to remove detector side channel attacks has been a notoriously hard problem in quantum cryptography. Here, we propose a simple solution to this problem--measurement-device-independent quantum key distribution (QKD). It not only removes all detector side channels, but also doubles the secure distance with conventional lasers. Our proposal can be implemented with standard optical components with low detection efficiency and highly lossy channels. In contrast to the previous solution of full device independent QKD, the realization of our idea does not require detectors of near unity detection efficiency in combination with a qubit amplifier (based on teleportation) or a quantum nondemolition measurement of the number of photons in a pulse. Furthermore, its key generation rate is many orders of magnitude higher than that based on full device independent QKD. The results show that long-distance quantum cryptography over say 200 km will remain secure even with seriously flawed detectors. PMID:22540686

Lo, Hoi-Kwong; Curty, Marcos; Qi, Bing

2012-03-30

96

An evaluation of strain measuring devices for ceramic composites  

NASA Technical Reports Server (NTRS)

A series of tensile tests was conducted on SiC/reaction bonded silicon nitrides (RBSN) composites using different methods of strain measurement. The tests were used to find the optimum strain sensing device for use with continuous fiber reinforced ceramic matrix composites in ambient and high temperature environments. Bonded resistance gages were found to offer excellent performance for room temperature tests. The clip-on gage offers the same performance, but less time is required for mounting it to the specimen. Low contact force extensometers track the strain with acceptable results at high specimen temperatures. Silicon carbide rods with knife edges are preferred. The edges must be kept sharp. The strain measuring devices should be mounted on the flat side of the specimen. This is in contrast to mounting on the rough thickness side.

Gyekenyesi, John Z.; Bartolotta, Paul A.

1991-01-01

97

An evaluation of strain measuring devices for ceramic composites  

NASA Technical Reports Server (NTRS)

A series of tensile tests were conducted on SiC/RBSN composites using different methods of strain measurement. The tests were used to find the optimum strain sensing device for use with continuous fiber reinforced ceramic matrix composites in ambient and high temperature environments. Bonded resistance strain gages were found to offer excellent performance for room temperature tests. The clip-on gage offers the same performance but significantly less time is required for mounting it to the specimen. Low contact force extensometers track the strain with acceptable results at high specimen temperatures. Silicon carbide rods with knife edges are preferred. The edges must be kept sharp. The strain measuring devices should be mounted on the flat side of the specimen. This is in contrast to mounting on the rough thickness side.

Gyekenyesi, John Z.; Bartolotta, Paul A.

1992-01-01

98

Measuring ionizing radiation with a mobile device  

NASA Astrophysics Data System (ADS)

In cases of nuclear disasters it is desirable to know one's personal exposure to radioactivity and the related health risk. Usually, Geiger-Mueller tubes are used to assess the situation. Equipping everyone with such a device in a short period of time is very expensive. We propose a method to detect ionizing radiation using the integrated camera of a mobile consumer device, e.g., a cell phone. In emergency cases, millions of existing mobile devices could then be used to monitor the exposure of its owners. In combination with internet access and GPS, measured data can be collected by a central server to get an overview of the situation. During a measurement, the CMOS sensor of a mobile device is shielded from surrounding light by an attachment in front of the lens or an internal shutter. The high-energy radiation produces free electrons on the sensor chip resulting in an image signal. By image analysis by means of the mobile device, signal components due to incident ionizing radiation are separated from the sensor noise. With radioactive sources present significant increases in detected pixels can be seen. Furthermore, the cell phone application can make a preliminary estimate on the collected dose of an individual and the associated health risks.

Michelsburg, Matthias; Fehrenbach, Thomas; Puente León, Fernando

2012-02-01

99

A uniform temperature heat sink for cooling of electronic devices  

Microsoft Academic Search

Experimental investigation of a heat sink for cooling of electronic devices is performed. The objective is to keep the operating temperature at a relatively low level of about 323–333 K, using a dielectric liquid that boils at a lower temperature, while reducing the undesired temperature variation in the both streamwise and transverse directions. The experimental study is based on systematic

G. Hetsroni; A. Mosyak; Z. Segal; G. Ziskind

2002-01-01

100

Variable-Temperature-Gradient Device for Solidification Research  

NASA Technical Reports Server (NTRS)

Device for research in solidification and crystal growth allows crystallization of melt observed as occurs. Temperature gradient across melt specimen increased or decreased rapidly while solidification front proceeds at constant speed across sample. Device moves sample at same speed, thereby holding position of liquid/solid interface stationary within field of optical microscope. Device, variabletemperature-gradient microscope stage, used to study crystal growth at constant rate while thermal driving force is varied.

Kaukler, W. F.

1985-01-01

101

Integrated Emissivity And Temperature Measurement  

DOEpatents

A multi-channel spectrometer and a light source are used to measure both the emitted and the reflected light from a surface which is at an elevated temperature relative to its environment. In a first method, the temperature of the surface and emissivity in each wavelength is calculated from a knowledge of the spectrum and the measurement of the incident and reflected light. In the second method, the reflected light is measured from a reference surface having a known reflectivity and the same geometry as the surface of interest and the emitted and the reflected light are measured for the surface of interest. These measurements permit the computation of the emissivity in each channel of the spectrometer and the temperature of the surface of interest.

Poulsen, Peter (Livermore, CA)

2005-11-08

102

Shock temperature measurements in ammonia  

SciTech Connect

Our first shock temperature measurements on a cryogenic target are reported for NH/sub 3/. A new fast optical pyrometer and a cryogenic specimen holder for liquid NH/sub 3/ were developed to measure shock temperatures of 4400 and 3600 K at pressures of 61 and 48 GPa. These conditions correspond to those in the ice layers in Uranus and Neptune. The shock temperature data are in reasonable agreement with an equation of state based on an intermolecular potential derived from NH/sub 3/ Hugoniot data.

Radousky, H.B.; Mitchell, A.C.; Nellis, W.J.; Ross, M.

1985-07-01

103

Containerless high temperature property measurements  

NASA Technical Reports Server (NTRS)

Containerless processing in the low gravity environment of space provides the opportunity to increase the temperature at which well controlled processing of and property measurements on materials is possible. This project was directed towards advancing containerless processing and property measurement techniques for application to materials research at high temperatures in space. Containerless high temperature material property studies include measurements of the vapor pressure, melting temperature, optical properties, and spectral emissivities of solid boron. The reaction of boron with nitrogen was also studied by laser polarimetric measurement of boron nitride film growth. The optical properties and spectral emissivities were measured for solid and liquid silicon, niobium, and zirconium; liquid aluminum and titanium; and liquid Ti-Al alloys of 5 to 60 atomic pct. titanium. Alternative means for noncontact temperature measurement in the absence of material emissivity data were evaluated. Also, the application of laser induced fluorescence for component activity measurements in electromagnetic levitated liquids was studied, along with the feasibility of a hybrid aerodynamic electromagnetic levitation technique.

Nordine, Paul C.; Weber, J. K. Richard; Krishnan, Shankar; Anderson, Collin D.

1991-01-01

104

Surface temperature measurements using a thin film thermal array  

NASA Technical Reports Server (NTRS)

A thin film device was designed and fabricated to measure surface temperatures. An array of eight integrated thermal sensors are mounted on a 0.002 inch (0.05 mm) Kapton film and multiplexed to obtain an area thermal measurement. The device was tested on a flat plate airfoil and demonstrated a temperature variation of 0.55 C maximum and 0.05 C minimum compared to embedded thermocouples. Future improvements are also discussed.

Dillon-Townes, L. A.; Johnson, P. B.; Ash, R. L.; Daryabeigi, K.; Whipple, J. C.

1989-01-01

105

Skin friction measuring device for aircraft  

NASA Technical Reports Server (NTRS)

A skin friction measuring device for measuring the resistance of an aerodynamic surface to an airstream is described. It was adapted to be mounted on an aircraft and is characterized by a friction plate adapted to be disposed in a flush relationship with the external surface of the aircraft and be displaced in response to skin friction drag. As an airstream is caused to flow over the surface, a potentiometer connected to the plate for providing an electrical output indicates the magnitude of the drag.

Montoya, L. C.; Bellman, D. R. (inventors)

1980-01-01

106

Chapter 1: Measurements in ! Temperature  

E-print Network

,000,000 mL 1000 mL #12;Chapter 1: Measurements in Chemistry ! Temperature in °C Water freezing point: 0 oC boiling point: 100 oC Chapter 1: Measurements in Chemistry ! Amount Mole (mol); SI standard 1 mol contains

Zakarian, Armen

107

Discriminated measures of strain and temperature in metallic specimen with embedded superimposed  

E-print Network

Discriminated measures of strain and temperature in metallic specimen with embedded superimposed a superimposed fibre Bragg gratings device to measure, localize and discriminate strain and temperature effects) exhibit different responses to an applied solicitation, thus, strain and temperature influences can

Boyer, Edmond

108

Fabrication of high temperature surface acoustic wave devices for sensor applications  

Microsoft Academic Search

Surface acoustic devices have been shown to be suitable not only for signal processing but also for sensor applications. In this paper high temperature surface acoustic wave devices based on gallium orthophosphate have been fabricated, using a lift-off technique and tested for high frequency applications at temperatures up to 600°C. The measured S-parameter (S11) has been used to study the

M. N. Hamidona; V. Skarda; N. M. White; F. Krispel; P. Krempl; M. Binhack; W. Buff

2005-01-01

109

Amorphous metallizations for high-temperature semiconductor device applications  

NASA Technical Reports Server (NTRS)

The initial results of work on a class of semiconductor metallizations which appear to hold promise as primary metallizations and diffusion barriers for high temperature device applications are presented. These metallizations consist of sputter-deposited films of high T sub g amorphous-metal alloys which (primarily because of the absence of grain boundaries) exhibit exceptionally good corrosion-resistance and low diffusion coefficients. Amorphous films of the alloys Ni-Nb, Ni-Mo, W-Si, and Mo-Si were deposited on Si, GaAs, GaP, and various insulating substrates. The films adhere extremely well to the substrates and remain amorphous during thermal cycling to at least 500 C. Rutherford backscattering and Auger electron spectroscopy measurements indicate atomic diffussivities in the 10 to the -19th power sq cm/S range at 450 C.

Wiley, J. D.; Perepezko, J. H.; Nordman, J. E.; Kang-Jin, G.

1981-01-01

110

Accelerated life testing and temperature dependence of device characteristics in GaAs CHFET devices  

NASA Technical Reports Server (NTRS)

Accelerated life testing of GaAs complementary heterojunction field effect transistors (CHFET) was carried out. Temperature dependence of single and synchronous rectifier CHFET device characteristics were also obtained.

Gallegos, M.; Leon, R.; Vu, D. T.; Okuno, J.; Johnson, A. S.

2002-01-01

111

Direct Measurement of Transformer Winding Hot Sport Temperature  

Microsoft Academic Search

Fiber optic temperature sensors were embedded diarectly within the windings of a large auto-transformer to measure hot spot temperatures under a variety of loading conditions. Numerous application problems were encountered, but a substantial amount of usable data was acquired. Sensor readings correlated well with the results from other measuring devices in locations where a direct comparison could be made. It

W. J. Mcnutt; J. C. Mciver; G. E. Leibinger; D. J. Fallon; K. A. Wickersheim

1984-01-01

112

An unheated permeation device for calibrating atmospheric VOC measurements  

NASA Astrophysics Data System (ADS)

The development of an unpowered permeation device for continuous calibration of in-situ instruments measuring atmospheric volatile organic compounds (VOCs) is described. Being lightweight and compact, and containing only negligible amounts of chemicals, the device is especially suited for field use such as on board aircraft. Its speciality is to maintain the permeation process in thermal equilibrium, so that the instantaneous permeation rate can be ascribed to a simple temperature measurement. This equilibrium state is maintained by a combination of three features: (i) a thin PTFE membrane as permeation medium which guarantees short stabilization times, (ii) a water bath as heat buffer, and (iii) a vacuum-panel based insulation, in which features (ii) and (iii) minimize temperature drifts to ~30 mK h-1 per Kelvin temperature difference to the environment. The respective uncertainty of the permeation rate due to thermal non-equilibrium is kept below 1%. An extensive theory part details the major permeation processes of gases through porous polymers, being Fick's diffusion, Knudsen flow, and viscous flow. Both the measured stabilization time and the measured temperature dependence of the permeation rate independently indicate that the permeation can be described by a viscous flow model, where diffusion of the gas molecules in large pores (having a diameter of >0.05 ?m) dominates.

Brito, J.; Zahn, A.

2011-10-01

113

High-Temperature Probe Station Developed to Characterize Microwave Devices Through 500 C  

NASA Technical Reports Server (NTRS)

A photograph and a block diagram of the high-temperature probe station are shown. The system consists of the ceramic heater mounted on a NASA shuttle tile insulator, a direct current power supply, a personal-computer-based data acquisition and temperature controller, microwave probes, a microscope, and a network analyzer. The ability to perform microwave tests at high temperatures is becoming necessary. There is now a need for sensors and communication circuits that can operate at 500 C and above for aircraft engine development and monitoring during flight. To address this need, researchers have fabricated devices using wide bandgap semiconductors such as SiC with targeted operating temperatures of 500 to 600 C. However, the microwave properties of these devices often change drastically with temperature, so any designs that are intended to be used in such an environment must be characterized at high temperatures. For some reliability, lifetime, and direct-current testing, the device under test can be packaged and characterized in an oven. However, for RF and microwave measurements, it is usually not possible to establish a calibrated reference plane at the device terminals within a package. In addition, the characteristics of the package would vary over a 500 C temperature range, and this would have to be accounted for when the data were analyzed. A high temperature probe station allows circuits and devices to be characterized through on wafer measurements across a broad temperature range with known reference plane. The conventional, commercially available thermal wafer-probe stations that are used to evaluate microwave devices across a controlled temperature range have a typical upper limit of 200 C. Standalone thermal heating chucks are available with an extended upper temperature range of 300 to 400 C. To effectively characterize devices at temperatures up to and surpassing 500 C, Glenn researchers developed a custom probe station. In the past, custom probe stations have been developed to test devices under other extreme environments, such as cryogenic temperatures as low as 37 K. Similarly, this custom probe station was specifically modified for high-temperature use. It allows devices to be measured quickly and flexibly, without the use of wire bonds and test fixtures. The probe station is shown making scattering parameter measurements from 1 to 50 GHz with a Hewlett-Packard 8510C Network Analyzer. There is a half-wafer of silicon directly on top of the heater to provide a uniform heated platform for our sample. A quarter wafer of silicon carbide forms the substrate for our test circuit of several transmission lines.

Downey, Alan N.; Schwartz, Zachary D.

2004-01-01

114

Junction Temperature Measurement of IGBTs Using Short Circuit Current  

SciTech Connect

In this paper, a method is proposed to measure the junction temperatures of IGBT discrete devices and modules using short circuit current. Experimental results show that the short circuit current has good sensitivity, linearity and selectivity, which is suitable to be used as temperature sensitive electrical parameters (TSEP). Test circuit and hardware design are proposed for junction temperature measurement in single phase and three phase convertes. By connecting a temperature measurement unit to the converter and giving a short circuit pulse, the IGBT junction temperature can be measured.

Wang, Fei [ORNL; Xu, Zhuxian [ORNL; Ning, Puqi [ORNL

2012-01-01

115

High-Temperature RF Probe Station For Device Characterization Through 500 deg C and 50 GHz  

NASA Technical Reports Server (NTRS)

A high-temperature measurement system capable of performing on-wafer microwave testing of semiconductor devices has been developed. This high temperature probe station can characterize active and passive devices and circuits at temperatures ranging from room temperature to above 500 C. The heating system uses a ceramic heater mounted on an insulating block of NASA shuttle tile material. The temperature is adjusted by a graphical computer interface and is controlled by the software-based feedback loop. The system is used with a Hewlett-Packard 8510C Network Analyzer to measure scattering parameters over a frequency range of 1 to 50 GHz. The microwave probes, cables, and inspection microscope are all shielded to protect from heat damage. The high temperature probe station has been successfully used to characterize gold transmission lines on silicon carbide at temperatures up to 540 C.

Schwartz, Zachary D.; Downey, Alan N.; Alterovitz, Samuel A.; Ponchak, George E.; Williams, W. D. (Technical Monitor)

2003-01-01

116

Colloidal-gold electrosensor measuring device  

DOEpatents

The present invention provides a new device for use in measuring lead levels in biological and environmental samples. Using square wave coulometry and colloidal gold particles impregnated on carbon electrodes, the present invention provides a rapid, reliable, portable and inexpensive means of detecting low lead levels. The colloidal gold modified electrodes have microelectrode array characteristics and produce significantly higher stripping detection signals for lead than are produced at bulk gold electrode surfaces. The method is effective in determining levels of lead down to at least 5 {micro}g/dL in blood samples as small as 10 {micro}L. 9 figs.

Wegner, S.; Harpold, M.A.; McCaffrey, T.M.; Morris, S.E.; Wojciechowski, M.; Zhao, J.; Henkens, R.W.; Naser, N.; O`Daly, J.P.

1995-11-21

117

Colloidal-gold electrosensor measuring device  

DOEpatents

The present invention provides a new device for use in measuring lead levels in biological and environmental samples. Using square wave coulometry and colloidal gold particles impregnated on carbon electrodes, the present invention provides a rapid, reliable, portable and inexpensive means of detecting low lead levels. The colloidal gold modified electrodes have microelectrode array characteristics and produce significantly higher stripping detection signals for lead than are produced at bulk gold electrode surfaces. The method is effective in determining levels of lead down to at least 5 .mu.g/dL in blood samples as small as 10 .mu.L.

Wegner, Steven (Chapel Hill, NC); Harpold, Michael A. (Durham, NC); McCaffrey, Terence M. (Durham, NC); Morris, Susan E. (Chapel Hill, NC); Wojciechowski, Marek (Cary, NC); Zhao, Junguo (Chapel Hill, NC); Henkens, Robert W. (Durham, NC); Naser, Najih (Durham, NC); O'Daly, John P. (Carrboro, NC)

1995-01-01

118

Large magnetoresistance at room-temperature in small-molecular-weight organic semiconductor sandwich devices  

NASA Astrophysics Data System (ADS)

We present an extensive study of a large, room temperature magnetoresistance (MR) effect in tris-(8-hydroxyquinoline) aluminum sandwich devices. The effect is similar to that previously discovered in ?-conjugated polymer devices. We characterize this effect and discuss its dependence on magnetic field direction, voltage, temperature, film thickness, and electrode materials. The MR effect reaches almost 10% at fields of 10 mT at room temperature. The effect shows only a weak temperature dependence and is independent of the sign and direction of the magnetic field. Measuring the devices' current-voltage characteristics, we find that the current depends on the voltage through a power-law. We find that the magnetic field changes the prefactor of the power-law. We also studied the effect of the magnetic field on the electroluminescence (MEL) of the devices and analyze the relationship between MR and MEL.

Mermer, Ö.; Veeraraghavan, G.; Francis, T. L.; Wohlgenannt, M.

2005-06-01

119

Diamond micro-Raman thermometers for accurate gate temperature measurements  

SciTech Connect

Determining the peak channel temperature in AlGaN/GaN high electron mobility transistors and other devices with high accuracy is an important and challenging issue. A surface-sensitive thermometric technique is demonstrated, utilizing Raman thermography and diamond microparticles to measure the gate temperature. This technique enhances peak channel temperature estimation, especially when it is applied in combination with standard micro-Raman thermography. Its application to other metal-covered areas of devices, such as field plates is demonstrated. Furthermore, this technique can be readily applied to other material/device systems.

Simon, Roland B.; Pomeroy, James W.; Kuball, Martin [Center for Device Thermography and Reliability, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom)

2014-05-26

120

High temperature stability of langasite surface acoustic wave devices  

Microsoft Academic Search

High temperature acoustic wave (AW) devices capable of operating above 600degC and in hostile environments have opened potential applications for monitoring industrial processes, power plants, and aerospace systems. The authors have reported on the development of thin film electrodes and protective ceramic layers to allow surface acoustic wave (SAW) device operation up to 800degC on langasite (LGS) crystals. This success

M. Pereira da Cunha; R. J. Lad; T. Moonlight; G. Bernhardt; D. J. Frankel

2008-01-01

121

Silicon carbide and diamond for high temperature device applications  

Microsoft Academic Search

The physical and chemical properties of wide bandgap semiconductors silicon carbide and diamond make these materials an ideal\\u000a choice for device fabrication for applications in many different areas, e.g. light emitters, high temperature and high power\\u000a electronics, high power microwave devices, micro-electromechanical system (MEMS) technology, and substrates. These semiconductors\\u000a have been recognized for several decades as being suitable for these

Magnus Willander; Milan Friesel; Qamar-ul Wahab; Boris Straumal

2006-01-01

122

An unheated permeation device for calibrating atmospheric VOC measurements  

NASA Astrophysics Data System (ADS)

The development of an unpowered permeation device for continuous calibration of in-situ instruments measuring atmospheric volatile organic compounds (VOCs) is described. Being lightweight and compact, and containing only negligible amounts of chemicals, the device is especially suited for field use such as onboard aircraft. Its speciality is to maintain the permeation process in thermal equilibrium, i.e. the instantaneous permeation rate can be ascribed via a simple temperature measurement. This equilibrium state is maintained by a combination of three features: (i) a thin PTFE membrane as permeation medium which guarantees short stabilization times, (ii) a water bath as heat buffer, and (iii) a vacuum-panel based insulation, in which features (ii) and (iii) minimize temperature drifts. The uncertainty of the permeation rate due to thermal non-equilibrium is kept below 1 %. An extensive theory part details the major permeation processes of gases through porous polymers, being Fick's diffusion, Knudsen flow, and viscous flow. Both the measured stabilization time and the measured temperature dependence of the permeation rate independently indicate that the permeation can be described by a viscous flow model, where diffusion of the gas molecules in large pores (having a diameter of >0.05 ?m) dominates.

Brito, J.; Zahn, A.

2011-05-01

123

Verilog-A Device Models for Cryogenic Temperature Operation of Bulk Silicon CMOS Devices  

NASA Technical Reports Server (NTRS)

Verilog-A based cryogenic bulk CMOS (complementary metal oxide semiconductor) compact models are built for state-of-the-art silicon CMOS processes. These models accurately predict device operation at cryogenic temperatures down to 4 K. The models are compatible with commercial circuit simulators. The models extend the standard BSIM4 [Berkeley Short-channel IGFET (insulated-gate field-effect transistor ) Model] type compact models by re-parameterizing existing equations, as well as adding new equations that capture the physics of device operation at cryogenic temperatures. These models will allow circuit designers to create optimized, reliable, and robust circuits operating at cryogenic temperatures.

Akturk, Akin; Potbhare, Siddharth; Goldsman, Neil; Holloway, Michael

2012-01-01

124

Temperature effects and corrections in volume measurements based on liquid-level detection  

Microsoft Academic Search

Temperature changes affect volume measurements in several ways. The dimensions of the tank, and the density and level of the liquid it contains vary with temperature. In addition, the response signal of the sensor and hence the response of the liquid-level detection device may change with temperature. Level measurement devices can be grouped according to four measurement points of reference:

S. Suda; B. Keisch

1993-01-01

125

Measurement-device-independent quantum cryptography  

E-print Network

In theory, quantum key distribution (QKD) provides information-theoretic security based on the laws of physics. Owing to the imperfections of real-life implementations, however, there is a big gap between the theory and practice of QKD, which has been recently exploited by several quantum hacking activities. To fill this gap, a novel approach, called measurement-device-independent QKD (mdiQKD), has been proposed. It can remove all side-channels from the measurement unit, arguably the most vulnerable part in QKD systems, thus offering a clear avenue towards secure QKD realisations. Here, we review the latest developments in the framework of mdiQKD, together with its assumptions, strengths and weaknesses.

Feihu Xu; Marcos Curty; Bing Qi; Hoi-Kwong Lo

2014-09-17

126

Measurement-device-independent quantum cryptography  

E-print Network

In theory, quantum key distribution (QKD) provides information-theoretic security based on the laws of physics. Owing to the imperfections of real-life implementations, however, there is a big gap between the theory and practice of QKD, which has been recently exploited by several quantum hacking activities. To fill this gap, a novel approach, called measurement-device-independent QKD (mdiQKD), has been proposed. It can remove all side-channels from the measurement unit, arguably the most vulnerable part in QKD systems, thus offering a clear avenue towards secure QKD realisations. Here, we review the latest developments in the framework of mdiQKD, together with its assumptions, strengths and weaknesses.

Feihu Xu; Marcos Curty; Bing Qi; Hoi-Kwong Lo

2015-01-07

127

High temperature thermoreflectance imaging and transient Harman characterization of thermoelectric energy conversion devices  

NASA Astrophysics Data System (ADS)

Advances in thin film growth technology have enabled the selective engineering of material properties to improve the thermoelectric figure of merit and thus the efficiency of energy conversion devices. Precise characterization at the operational temperature of novel thermoelectric materials is crucial to evaluate their performance and optimize their behavior. However, measurements on thin film devices are subject to complications from the growth substrate, non-ideal contacts, and other thermal and electrical parasitic effects. In this manuscript, we determine the cross-plane thermoelectric material properties in a single measurement of a 25 ?m InGaAs thin film with embedded ErAs (0.2%) nanoparticles using the bipolar transient Harman method in conjunction with thermoreflectance thermal imaging at temperatures up to 550 K. This approach eliminates discrepancies and potential device degradation from the multiple measurements necessary to obtain individual material parameters. In addition, we present a strategy for optimizing device geometry to mitigate the effect of both electrical and thermal parasitics during the measurement. Finite element method simulations are utilized to analyze non-uniform current and temperature distributions over the device area as well as the three dimensional current path for accurate extraction of material properties from the thermal images. Results are compared with independent in-plane and 3? measurements of thermoelectric material properties for the same material composition and are found to match reasonably well; the obtained figure of merit matches within 15% at room and elevated temperatures.

Favaloro, T.; Ziabari, A.; Bahk, J.-H.; Burke, P.; Lu, H.; Bowers, J.; Gossard, A.; Bian, Z.; Shakouri, A.

2014-07-01

128

Low-Temperature Processes for MEMS Device Fabrication  

NASA Astrophysics Data System (ADS)

The high temperatures typical in semiconductor and conventional MEMS fabrication limit the material choices in MEMS structures. This paper reviews some of the low-temperature processes and techniques available for MEMS fabrication and describes some characteristics of these techniques and practical process examples. The techniques described are plasma-enhanced chemical vapour deposition, atomic layer deposition, reactive sputtering, vapour phase hydrofluoric acid etching of low-temperature oxides, and low-temperature wafer bonding. As a practical example of the use of these techniques, the basic characteristics of a MEMS switch and other devices fabricated at VTT are presented.

Kiihamäki, Jyrki; Kattelus, Hannu; Blomberg, Martti; Puurunen, Riikka; Laamanen, Mari; Pekko, Panu; Saarilahti, Jaakko; Ritala, Heini; Rissanen, Anna

129

Large magnetoresistance at room temperature in semiconducting polymer sandwich devices  

NASA Astrophysics Data System (ADS)

We report on the discovery of a large, room temperature magnetoresistance (MR) effect in polyfluorene sandwich devices in weak magnetic fields. We characterize this effect and discuss its dependence on field direction, voltage, temperature, film thickness, electrode materials, and (unintentional) impurity concentration. Negative MR is usually observed, but positive MR can also be achieved under high applied electric fields. The MR effect reaches up to 10% at fields of 10 mT at room temperature. The effect shows only a weak temperature dependence and is independent of the sign and direction of the magnetic field. We find that the effect is related to the hole current in the devices. To the best of our knowledge, the discovered effect is not adequately described by any of the MR mechanisms known to date.

Francis, T. L.; Mermer, Ö.; Veeraraghavan, G.; Wohlgenannt, M.

2004-11-01

130

Simple microcalorimeter for measuring microgram samples at low temperatures  

Microsoft Academic Search

An innovative microcalorimeter has been developed for measuring specific heat of very small microgram samples in the temperature range from 1.5 to 50 K and in magnetic fields up to 11 T. The device is built from a commercial sapphire temperature chip (Cernox), which is modified by means of standard microfabrication techniques and which is used as a sample holder,

S. G. Doettinger-Zech; M. Uhl; D. L. Sisson; A. Kapitulnik

2001-01-01

131

High Temperature Thermoelectric Device Concept Using Large Area PN Junctions  

NASA Astrophysics Data System (ADS)

A new high temperature thermoelectric device concept using large area nanostructured silicon p-type and n-type ( PN) junctions is presented. In contrast to conventional thermoelectric generators, where the n-type and p-type semiconductors are connected electrically in series and thermally in parallel, we experimentally demonstrate a device concept in which a large area PN junction made from highly doped densified silicon nanoparticles is subject to a temperature gradient parallel to the PN interface. In the proposed device concept, the electrical contacts are made at the cold side eliminating the hot side substrate and difficulties that go along with high temperature electrical contacts. This concept allows temperature gradients greater than 300 K to be experimentally applied with hot side temperatures larger than 800 K. Electronic properties of the PN junctions and power output characterizations are presented. A fundamental working principle is discussed using a particle network model with temperature and electric fields as variables, and which considers electrical conductivity and thermal conductivity according to Fourier's law, as well as Peltier and Seebeck effects.

Chavez, R.; Angst, S.; Hall, J.; Stoetzel, J.; Kessler, V.; Bitzer, L.; Maculewicz, F.; Benson, N.; Wiggers, H.; Wolf, D.; Schierning, G.; Schmechel, R.

2014-06-01

132

High-transition-temperature superconducting quantum interference devices  

Microsoft Academic Search

The advent of high-Tc superconductors gave great impetus to the development of thin-film superconducting quantum interference devices (SQUIDs) for operation at temperatures up to the boiling point of liquid nitrogen, 77 K. The spectral density of the white flux noise can be calculated analytically for rf SQUIDs and by computer simulation for dc SQUIDs; however, observed noise spectral densities are

D. Koelle; R. Kleiner; F. Ludwig; E. Dantsker; John Clarke

1999-01-01

133

Ultrasonic device for measuring periodontal attachment levels  

NASA Astrophysics Data System (ADS)

Periodontal disease is manifested clinically by a degradation of the ligament that attaches the tooth to the bone. The most widely used diagnostic tool for assessment of periodontal diseases, measurement of periodontal attachment loss with a manual probe, may overestimate attachment loss by as much as 2 mm in untreated sites, while underestimating attachment loss by an even greater margin following treatment. Manual probing is also invasive, which causes patient discomfort. This work describes the development and testing of an ultrasonographic periodontal probe designed to replace manual probing. It uses a thin stream of water to project an ultrasonic beam into the periodontal pocket, and then measures echoes off features within the pocket. To do so, the ultrasonic beam must be narrowed from 2 (the diameter of the transducer) to 0.5 mm (the approximate width of the periodontal pocket at the gingival margin). The proper choice of transducer frequency, the proper method for controlling water flow from the probe, and a model for interpreting these echoes are also addressed. Initial results indicate that the device measures echoes from the hard tissue of the tooth surface, and that the periodontal attachment level can be inferred from these echoes.

Lynch, J. E.; Hinders, M. K.

2002-07-01

134

Infrared Emissivity Measurements of Building and Civil Engineering Materials: A New Device for Measuring Emissivity  

NASA Astrophysics Data System (ADS)

The knowledge of the infrared emissivity of materials used in buildings and civil engineering structures is useful for two specific approaches. First, quantitative diagnosis of buildings or civil engineering infrastructures by infrared thermography requires emissivity values in the spectral bandwidth of the camera used for measurements, in order to obtain accurate surface temperatures; for instance, emissivity in the band III domain is required when using cameras with uncooled detectors (such as micro-bolometer arrays). Second, setting up accurate thermal balances by numerical modeling requires the total emissivity value for a large wavelength domain; this is, for instance, the case for computing the road surface temperature to predict ice occurrence. Furthermore, periodical surveys of emissivity variations due to aging or soiling of surfaces could be useful in many situations such as thermal mapping of roads or building insulation diagnosis. The use of portable emissivity measurement devices is required for that purpose. A device using an indirect measurement method was previously developed in our lab; the method uses measurement of the reflectivity from a modulated IR source and requires calibration with a highly reflective surface. However, that device uses a low-frequency, thermal modulation well adapted to laboratory measurements but unfit for fast and in situ measurements. Therefore, a new, portable system which retains the principle of an indirect measurement but uses a faster-frequency, mechanical modulation more appropriate to outdoor measurements was developed. Both devices allow measurements in the broad m to m) and narrow m to m) bands. Experiments were performed on a large number of materials commonly used in buildings and civil engineering structures. The final objective of this work is to build a database of emissivity of these materials. A comparison of laboratory and on-site measurements of emissivity values obtained in both spectral bands will be presented along with an estimation and an analysis of measurement uncertainties.

Monchau, Jean-Pierre; Marchetti, Mario; Ibos, Laurent; Dumoulin, Jean; Feuillet, Vincent; Candau, Yves

2014-10-01

135

Detection of gas hydrates by the measurement of instantaneous temperature  

E-print Network

Probes 38 TABLE OF CONTENTS (continued) WSTP Temperature Probe ADARA Temperature Tool TEST SETUP AND PROCEDURE Page 39 40 43 Selection of Temperature Measuring Device Brass Discs and Thermistors Brass Discs and Thermocouples Brass Discs... Compressive Strength of Frozen Sand vs Strain Rate 17 Schlumberger Well Logs at Site 570 10. Hot Plate Apparatus 31 12. 13. Thermal Needle Probes Transient Needle Probes Brass Discs Used to Study the Response 34 37 Time 47 14. Response Time...

Dinakaran, Srikanth

2012-06-07

136

Measurement of Device Parameters Using Image Recovery Techniques in Large-Scale IC Devices  

NASA Technical Reports Server (NTRS)

Devices that respond to radiation on a cell level will produce histograms showing the relative frequency of cell damage as a function of damage. The measured distribution is the convolution of distributions from radiation responses, measurement noise, and manufacturing parameters. A method of extracting device characteristics and parameters from measured distributions via mathematical and image subtraction techniques is described.

Scheick, Leif; Edmonds, Larry

2004-01-01

137

Advanced devices and systems for radiation measurements  

SciTech Connect

The authors` most recent work continues their long-standing efforts to develop semiconductor detectors based on the collection of only a single type of charge carrier. Their best results are an extension of the principle of coplanar electrodes first described by Paul Luke of Lawrence Berkeley Laboratory 18 months ago. This technique, described in past progress reports, has the effect of deriving an output signal from detectors that depends only on the motion of carriers close to one surface. Since nearly all of these carriers are of one type (electrons) that are attracted to that electrode, the net effect is to nearly eliminate the influence of hole motion on the properties of the output signal. The result is that the much better mobility of electrons in compound semiconductors materials such as CZT can now be exploited without the concurrent penalty of poor hole collection. They have also developed new techniques in conjunction with the coplanar electrode principle that extends the technique into a new dimension. By proper processing of signals from the opposite electrode (the cathode) from the coplanar surface, they are able to derive a signal that is a good indication of the depth of interaction at which the charge carriers were initially formed. They have been the first group to demonstrate this technique, and examples of separate pulse height spectra recorded at a variety of different depths of interaction are shown in several of the figures that follow. Obtaining depth information is one step in the direction of obtaining volumetric point-of-interaction information from the detector. If one could known the coordinates of each specific interaction, then corrections could be applied to account for the inhomogeneities that currently plague many room-temperature devices.

Knoll, G.F.; Wehe, D.K.; He, Z.; Barrett, C.; Miyamoto, J.

1996-06-01

138

Thin-film thermoelectric devices with high room-temperature figures of merit  

Microsoft Academic Search

Thermoelectric materials are of interest for applications as heat pumps and power generators. The performance of thermoelectric devices is quantified by a figure of merit, ZT, where Z is a measure of a material's thermoelectric properties and T is the absolute temperature. A material with a figure of merit of around unity was first reported over four decades ago, but

Rama Venkatasubramanian; Edward Siivola; Thomas Colpitts; Brooks O'Quinn

2001-01-01

139

Measurement of relative permittivity of LTCC ceramic at different temperatures  

NASA Astrophysics Data System (ADS)

Devices based on LTCC (low-temperature co-fired ceramic) technology are more widely applied in high temperature environments, and the temperature-dependent properties of the LTCC material play an important role in measurements of the characteristics of these devices at high temperature. In this paper, the temperature-dependence of the relative permittivity of DuPont 951 LTCC ceramic is studied from room temperature to 500 °C. An expression for relative permittivity is obtained, which relates the relative permittivity to the resonant frequency, inductance, parasitic capacitance and electrode capacitance of the LTCC sample. Of these properties, the electrode capacitance is the most strongly temperature-dependent. The LTCC sample resonant frequency, inductance and parasitic capacitance were measured (from room temperature to 500 °C) with a high temperature measurement system comprising a muffle furnace and network analyzer. We found that the resonant frequency reduced and the inductance and parasitic capacitance increased slightly as the temperature increases. The relative permittivity can be calculated from experimental frequency, inductance and parasitic capacitance measurements. Calculating results show that the relative permittivity of DuPont 951 LTCC ceramic ceramic increases to 8.21 from room temperature to 500 °C.

Tan, Qiulin; Kang, Hao; Qin, Li; Xiong, Jijun; Zhou, Zhaoying; Zhang, Wendong; Luo, Tao; Xue, Chenyang; Liu, Jun

2014-03-01

140

Status of local transport measurements and analysis in toroidal devices  

SciTech Connect

This paper reviews the status of methods used to analyze local transport of particles, energy, and angular momentum in plasmas contained in toroidal fusion devices. The standard technique at present is based on determination of particle, energy, and momentum fluxes through analysis based on measured profiles of density, temperature and angular rotation speed and on calculation of all sources of particles, energy, and momentum. Recent experiments have also been done using perturbations of local density, temperature, or angular rotation speed caused by modulating the input sources. The local transport information is then extracted from the time history of the perturbations. These two techniques are contrasted and the strengths of each are discussed in this paper. Recommendations for further work needed to make progress in understanding transport are also given.

Burrell, K.H. (General Atomics, San Diego, CA 92138 (USA)); Gentle, K.W. (University of Texas, Austin, Texas 78712 (USA)); Luhmann, N.C. Jr. (University of California at Los Angeles, Los Angeles, CA 90024 (USA)); Marmar, E.S. (Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (USA)); Murakami, M. (Oak Ridge National Laboratory, Oak Ridge, TN 37837 (USA)); Schoenberg, K.F. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (USA)); Tang, W.M.; Zarnstorff, M.C. (Plasma Physics Laboratory, Princeton, New Jersey 08543 (USA))

1990-12-01

141

Evaluation of Advanced COTS Passive Devices for Extreme Temperature Operation  

NASA Technical Reports Server (NTRS)

Electronic sensors and circuits are often exposed to extreme temperatures in many of NASA deep space and planetary surface exploration missions. Electronics capable of operation in harsh environments would be beneficial as they simplify overall system design, relax thermal management constraints, and meet operational requirements. For example, cryogenic operation of electronic parts will improve reliability, increase energy density, and extend the operational lifetimes of space-based electronic systems. Similarly, electronic parts that are able to withstand and operate efficiently in high temperature environments will negate the need for thermal control elements and their associated structures, thereby reducing system size and weight, enhancing its reliability, improving its efficiency, and reducing cost. Passive devices play a critical role in the design of almost all electronic circuitry. To address the needs of systems for extreme temperature operation, some of the advanced and most recently introduced commercial-off-the-shelf (COTS) passive devices, which included resistors and capacitors, were examined for operation under a wide temperature regime. The types of resistors investigated included high temperature precision film, general purpose metal oxide, and wirewound.

Patterson, Richard; Hammoud, Ahmad; Dones, Keishla R.

2009-01-01

142

Ergonomic analysis of slip-resistance measurement devices  

Microsoft Academic Search

Several measurement devices and techniques have been developed during the past 50 years in an attempt to quantify the static and\\/or dynamic coefficient of friction (COF) of shoe and floor surface interfaces. Much of this work has been laboratory research with bulky equipment, but recently portable measurement devices have evolved to the extent that field measurements can be taken. Six

ROBERT O. ANDRES; DON B. CHAFFIN

1985-01-01

143

Simple microcalorimeter for measuring microgram samples at low temperatures  

NASA Astrophysics Data System (ADS)

An innovative microcalorimeter has been developed for measuring specific heat of very small microgram samples in the temperature range from 1.5 to 50 K and in magnetic fields up to 11 T. The device is built from a commercial sapphire temperature chip (Cernox), which is modified by means of standard microfabrication techniques and which is used as a sample holder, temperature sensor, and sample heater. Compared to existing microcalorimeters the simple design of our instrument allows a fabrication of the device in a few process steps by using facilities present in a standard laboratory clean room. As an illustrative example for the performance of our device, the specific heat of an underdoped (La1-xSrx)2CuO4 and CaRuO3 single crystal has been measured by means of the relaxation time method as well as the ac method.

Doettinger-Zech, S. G.; Uhl, M.; Sisson, D. L.; Kapitulnik, A.

2001-05-01

144

Compensated vibrating optical fiber pressure measuring device  

DOEpatents

A microbending optical fiber is attached under tension to a diaphragm to se a differential pressure applied across the diaphragm which it causes it to deflect. The fiber is attached to the diaphragm so that one portion of the fiber, attached to a central portion of the diaphragm, undergoes a change in tension; proportional to the differential pressure applied to the diaphragm while a second portion attached at the periphery of the diaphragm remains at a reference tension. Both portions of the fiber are caused to vibrate at their natural frequencies. Light transmitted through the fiber is attenuated by both portions of the tensioned sections of the fiber by an amount which increases with the curvature of fiber bending so that the light signal is modulated by both portions of the fiber at separate frequencies. The modulated light signal is transduced into a electrical signal. The separate modulation signals are detected to generate separate signals having frequencies corresponding to the reference and measuring vibrating sections of the continuous fiber, respectively. A signal proportional to the difference between these signals is generated which is indicative of the measured pressure differential across the diaphragm. The reference portion of the fiber is used to compensate the pressure signal for zero and span changes resulting from ambient temperature and humidity effects upon the fiber and the transducer fixture.

Fasching, George E. (Morgantown, WV); Goff, David R. (Christiansburg, VA)

1987-01-01

145

Electron cyclotron beam measurement system in the Large Helical Device.  

PubMed

In order to evaluate the electron cyclotron (EC) heating power inside the Large Helical Device vacuum vessel and to investigate the physics of the interaction between the EC beam and the plasma, a direct measurement system for the EC beam transmitted through the plasma column was developed. The system consists of an EC beam target plate, which is made of isotropic graphite and faces against the EC beam through the plasma, and an IR camera for measuring the target plate temperature increase by the transmitted EC beam. This system is applicable to the high magnetic field (up to 2.75 T) and plasma density (up to 0.8 × 10(19) m(-3)). This system successfully evaluated the transmitted EC beam profile and the refraction. PMID:25430387

Kamio, S; Takahashi, H; Kubo, S; Shimozuma, T; Yoshimura, Y; Igami, H; Ito, S; Kobayashi, S; Mizuno, Y; Okada, K; Osakabe, M; Mutoh, T

2014-11-01

146

Electron cyclotron beam measurement system in the Large Helical Device  

SciTech Connect

In order to evaluate the electron cyclotron (EC) heating power inside the Large Helical Device vacuum vessel and to investigate the physics of the interaction between the EC beam and the plasma, a direct measurement system for the EC beam transmitted through the plasma column was developed. The system consists of an EC beam target plate, which is made of isotropic graphite and faces against the EC beam through the plasma, and an IR camera for measuring the target plate temperature increase by the transmitted EC beam. This system is applicable to the high magnetic field (up to 2.75 T) and plasma density (up to 0.8 × 10{sup 19} m{sup ?3}). This system successfully evaluated the transmitted EC beam profile and the refraction.

Kamio, S., E-mail: kamio@nifs.ac.jp; Takahashi, H.; Kubo, S.; Shimozuma, T.; Yoshimura, Y.; Igami, H.; Ito, S.; Kobayashi, S.; Mizuno, Y.; Okada, K.; Osakabe, M.; Mutoh, T. [National Institute for Fusion Science, Toki 509-5292 (Japan)

2014-11-15

147

Temperature and Strain Coefficient of Velocity for Langasite SAW Devices  

NASA Technical Reports Server (NTRS)

Surface Acoustic Wave sensors on Langasite substrates are being investigated for aerospace applications. Characterization of the Langasite material properties must be performed before sensors can be installed in research vehicles. The coefficients of velocity for both strain and temperature have been determined. These values have also been used to perform temperature compensation of the strain measurements.

Wilson, W. C.; Atkinson, G. M.

2013-01-01

148

Graphene, a material for high temperature devices – intrinsic carrier density, carrier drift velocity, and lattice energy  

PubMed Central

Heat has always been a killing matter for traditional semiconductor machines. The underlining physical reason is that the intrinsic carrier density of a device made from a traditional semiconductor material increases very fast with a rising temperature. Once reaching a temperature, the density surpasses the chemical doping or gating effect, any p-n junction or transistor made from the semiconductor will fail to function. Here, we measure the intrinsic Fermi level (|EF| = 2.93?kBT) or intrinsic carrier density (nin = 3.87 × 106?cm?2K?2·T2), carrier drift velocity, and G mode phonon energy of graphene devices and their temperature dependencies up to 2400?K. Our results show intrinsic carrier density of graphene is an order of magnitude less sensitive to temperature than those of Si or Ge, and reveal the great potentials of graphene as a material for high temperature devices. We also observe a linear decline of saturation drift velocity with increasing temperature, and identify the temperature coefficients of the intrinsic G mode phonon energy. Above knowledge is vital in understanding the physical phenomena of graphene under high power or high temperature. PMID:25044003

Yin, Yan; Cheng, Zengguang; Wang, Li; Jin, Kuijuan; Wang, Wenzhong

2014-01-01

149

121. Man with temperature probe aimed at armature measuring temperature ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

121. Man with temperature probe aimed at armature measuring temperature as armature heats up between the two electrodes. March 27, 1985 - Statue of Liberty, Liberty Island, Manhattan, New York, New York County, NY

150

Device and method for measuring thermal conductivity of thin films  

NASA Technical Reports Server (NTRS)

A device and method are provided for measuring the thermal conductivity of rigid or flexible, homogeneous or heterogeneous, thin films between 50 .mu.m and 150 .mu.m thick with relative standard deviations of less than five percent. The specimen is sandwiched between like material, highly conductive upper and lower slabs. Each slab is instrumented with six thermocouples embedded within the slab and flush with their corresponding surfaces. A heat source heats the lower slab and a heat sink cools the upper slab. The heat sink also provides sufficient contact pressure onto the specimen. Testing is performed within a vacuum environment (bell-jar) between 10.sup.-3 to 10.sup.-6 Torr. An anti-radiant shield on the interior surface of the bell-jar is used to avoid radiation heat losses. Insulation is placed adjacent to the heat source and adjacent to the heat sink to prevent conduction losses. A temperature controlled water circulator circulates water from a constant temperature bath through the heat sink. Fourier's one-dimensional law of heat conduction is the governing equation. Data, including temperatures, are measured with a multi-channel data acquisition system. On-line computer processing is used for thermal conductivity calculations.

Amer, Tahani R. (Inventor); Subramanian, Chelakara (Inventor); Upchurch, Billy T. (Inventor); Alderfer, David W. (Inventor); Sealey, Bradley S. (Inventor); Burkett, Jr., Cecil G. (Inventor)

2001-01-01

151

Cutting temperature measurement while machining – a review  

Microsoft Academic Search

Purpose – This paper gives the background to the measurement of metal cutting temperatures and a review of the practicality of the various methods of measuring cutting temperature while machining metals. Design\\/methodology\\/approach – The review was compiled after a literature search, visits to other research establishments and discussions with other researchers in the machining\\/temperature measurement field. Findings – Information about

J. M. Longbottom; J. D. Lanham

2005-01-01

152

Testing and Validation of Phasor Measurement Based Devices  

E-print Network

this project, contact Anurag K Srivastava, Project Leader Assistant Professor, The School of ElectricalTesting and Validation of Phasor Measurement Based Devices and Algorithms Final Project Report #12;#12;Testing and Validation of Phasor Measurement Based Devices and Algorithms Final Project Report

153

27 CFR 24.36 - Instruments and measuring devices.  

Code of Federal Regulations, 2011 CFR

27 Alcohol, Tobacco Products...2011-04-01 false Instruments and measuring devices...Section 24.36 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX...Authorities § 24.36 Instruments and measuring...

2011-04-01

154

27 CFR 24.36 - Instruments and measuring devices.  

Code of Federal Regulations, 2010 CFR

27 Alcohol, Tobacco Products...2010-04-01 false Instruments and measuring devices...Section 24.36 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX...Authorities § 24.36 Instruments and measuring...

2010-04-01

155

27 CFR 24.36 - Instruments and measuring devices.  

Code of Federal Regulations, 2012 CFR

27 Alcohol, Tobacco Products...2012-04-01 false Instruments and measuring devices...Section 24.36 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX...Authorities § 24.36 Instruments and measuring...

2012-04-01

156

27 CFR 24.36 - Instruments and measuring devices.  

Code of Federal Regulations, 2014 CFR

27 Alcohol, Tobacco Products...2014-04-01 false Instruments and measuring devices...Section 24.36 Alcohol, Tobacco Products...OF THE TREASURY ALCOHOL WINE Administrative...Authorities § 24.36 Instruments and measuring...

2014-04-01

157

27 CFR 24.36 - Instruments and measuring devices.  

Code of Federal Regulations, 2013 CFR

27 Alcohol, Tobacco Products...2013-04-01 false Instruments and measuring devices...Section 24.36 Alcohol, Tobacco Products...OF THE TREASURY ALCOHOL WINE Administrative...Authorities § 24.36 Instruments and measuring...

2013-04-01

158

Accurate Measurement of Packaged RF Devices  

E-print Network

or stripline as the transmission line medium. Microstrip consists of conductor traces that are deposited on a substrate, which sits on top of a ground plane. One example would be a single-layer PC board. Stripline for RF devices can be grouped into 3 categories: surface mount, TO cans, and stripline. Surface mount

Anlage, Steven

159

Nanometer-scale temperature imaging for independent observation of Joule and Peltier effects in phase change memory devices.  

PubMed

This paper reports a technique for independent observation of nanometer-scale Joule heating and thermoelectric effects, using atomic force microscopy (AFM) based measurements of nanometer-scale temperature fields. When electrical current flows through nanoscale devices and contacts the temperature distribution is governed by both Joule and thermoelectric effects. When the device is driven by an electrical current that is both periodic and bipolar, the temperature rise due to the Joule effect is at a different harmonic than the temperature rise due to the Peltier effect. An AFM tip scanning over the device can simultaneously measure all of the relevant harmonic responses, such that the Joule effect and the Peltier effect can be independently measured. Here we demonstrate the efficacy of the technique by measuring Joule and Peltier effects in phase change memory devices. By comparing the observed temperature responses of these working devices, we measure the device thermopower, which is in the range of 30 ± 3 to 250 ± 10 ?V K(-1). This technique could facilitate improved measurements of thermoelectric phenomena and properties at the nanometer-scale. PMID:25273761

Grosse, Kyle L; Pop, Eric; King, William P

2014-09-01

160

Nanometer-scale temperature imaging for independent observation of Joule and Peltier effects in phase change memory devices  

NASA Astrophysics Data System (ADS)

This paper reports a technique for independent observation of nanometer-scale Joule heating and thermoelectric effects, using atomic force microscopy (AFM) based measurements of nanometer-scale temperature fields. When electrical current flows through nanoscale devices and contacts the temperature distribution is governed by both Joule and thermoelectric effects. When the device is driven by an electrical current that is both periodic and bipolar, the temperature rise due to the Joule effect is at a different harmonic than the temperature rise due to the Peltier effect. An AFM tip scanning over the device can simultaneously measure all of the relevant harmonic responses, such that the Joule effect and the Peltier effect can be independently measured. Here we demonstrate the efficacy of the technique by measuring Joule and Peltier effects in phase change memory devices. By comparing the observed temperature responses of these working devices, we measure the device thermopower, which is in the range of 30 ± 3 to 250 ± 10 ?V K-1. This technique could facilitate improved measurements of thermoelectric phenomena and properties at the nanometer-scale.

Grosse, Kyle L.; Pop, Eric; King, William P.

2014-09-01

161

High Density And High Temperature Plasmas In Large Helical Device  

NASA Astrophysics Data System (ADS)

For the realization of the fusion reactor, it is necessary to confine high density and high temperature plasma for a time, which is well known as the Lawson criterion. To improve the plasma or confinement performance, vigorous experiments have been performed in the Large Helical Device (LHD) in National Institute for Fusion Science, which is the largest superconducting heliotron device with R = 3.9 m r = 0.6 m, Bt = 3 T. Recently a promising confinement regime called Super Dense Core (SDC) mode was discovered. An extremely high density core region with more than ~ 1 × 10^20 m-3 is obtained with the formation of an Internal Diffusion Barrier (IDB). The density gradient at the IDB (? = 0.6) is very high and the particle confinement in the core region is ~ 0.2 s. It is expected, for the future reactor, that the IDB-SDC mode has a possibility to achieve the self-ignition condition with lower temperature than expected before. The IDB-SDC mode is also favorable from the engineering point of view since one can moderate demands for heating devices and plasma facing components. In order to achieve the IDB-SDC mode, the central fuelling with the pellet injection and the low recycling condition are essential. A repetitive pellet injector was newly developed to continuously feed the particle source to the central region. For the recycling control, the effective divertor system should be employed to control the edge plasma. Conventional approaches to increase the temperature have also been tried in LHD. For the ion heating, the perpendicular neutral beam injection effectively increased the ion temperature more than 10 keV with the formation of the internal transport barrier (ITB). In the core region, the heat conductivity is improved to the neoclassical level, while no clear ITB for electron was seen. Another interesting phenomenon called "impurity hole" was observed inside the ITB. During the high ion temperature discharge, the im- purity density in the core region becomes low and its profile becomes hollow. The impurity atoms are pumped out, in spite of the negative electric field (ion root) inside the ITB. In the lecture, the mechanism of the impurity hole will also be discussed, together with the theoretical background and numerical results.

Komori, A.

2010-07-01

162

A device to investigate the delamination strength in laminates at room and cryogenic temperature  

NASA Astrophysics Data System (ADS)

We construct an instrument to study the behavior of delamination strength in laminates which can be defined as the critical transverse stress at which an actual delamination occurs. The device allows the anvil measurements at room temperature or the liquid nitrogen temperature. For the electro-magnetic laminated materials (e.g., a superconducting YaBa2Cu3O7-x coated conductor which has a typical laminated structure), the delamination strength was measured while the properties of transport current were also recorded. Moreover, the influences of external magnetic field on the delamination strength were presented.

Zhang, Xingyi; Liu, Wei; Zhou, Jun; Zhou, You-He

2014-12-01

163

A device to investigate the delamination strength in laminates at room and cryogenic temperature.  

PubMed

We construct an instrument to study the behavior of delamination strength in laminates which can be defined as the critical transverse stress at which an actual delamination occurs. The device allows the anvil measurements at room temperature or the liquid nitrogen temperature. For the electro-magnetic laminated materials (e.g., a superconducting YaBa2Cu3O7-x coated conductor which has a typical laminated structure), the delamination strength was measured while the properties of transport current were also recorded. Moreover, the influences of external magnetic field on the delamination strength were presented. PMID:25554334

Zhang, Xingyi; Liu, Wei; Zhou, Jun; Zhou, You-He

2014-12-01

164

Measurement of thermodynamic temperature of high temperature fixed points  

SciTech Connect

The paper is devoted to VNIIOFI's measurements of thermodynamic temperature of the high temperature fixed points Co-C, Pt-C and Re-C within the scope of the international project coordinated by the Consultative Committee for Thermometry working group 5 'Radiation Thermometry'. The melting temperatures of the fixed points were measured by a radiance mode radiation thermometer calibrated against a filter radiometer with known irradiance spectral responsivity via a high temperature black body. This paper describes the facility used for the measurements, the results and estimated uncertainties.

Gavrilov, V. R.; Khlevnoy, B. B.; Otryaskin, D. A.; Grigorieva, I. A.; Samoylov, M. L.; Sapritsky, V. I. [All-Russian Research Institute for Optical and Physical Measurements (VNIIOFI), 46 Ozernaya St., Moscow 119361 (Russian Federation)] [All-Russian Research Institute for Optical and Physical Measurements (VNIIOFI), 46 Ozernaya St., Moscow 119361 (Russian Federation)

2013-09-11

165

Test device for measuring permeability of a barrier material  

DOEpatents

A test device for measuring permeability of a barrier material. An exemplary device comprises a test card having a thin-film conductor-pattern formed thereon and an edge seal which seals the test card to the barrier material. Another exemplary embodiment is an electrical calcium test device comprising: a test card an impermeable spacer, an edge seal which seals the test card to the spacer and an edge seal which seals the spacer to the barrier material.

Reese, Matthew; Dameron, Arrelaine; Kempe, Michael

2014-03-04

166

Temperature and Heat Transfer Measurements Cengiz Camci  

E-print Network

EAE077 Chapter 11 Temperature and Heat Transfer Measurements Cengiz Camci Turbomachinery Aero Resistive Temperature Transducers 2 3 Thermocouples 3 4 Bi-Metallic Temperature Sensors 7 5 Diode-Based Temperature Sensors 7 6 Liquid Crystal Thermometry 7 7 Infrared Thermometry and Pyrometer 9 8 Heat Transfer

Camci, Cengiz

167

Low Cost Device For Light Flicker Measurement  

Microsoft Academic Search

A new instrument for the evaluation of disturbances caused by variations in lamp voltage (light flicker) is proposed, based on light intensity measurements. Unlike current standard (IEC EN 61000-4-15), which determines flicker severity by filtering powering voltage measurements with a standard lamp model (230V\\/60W), the presented methodology includes the lamp itself in the measurement process, thus realizing an objective measurement

Daniele Gallo; Carmine Landi; Nicola Pasquino

168

Proton irradiation of a swept charge device at cryogenic temperature and the subsequent annealing  

NASA Astrophysics Data System (ADS)

A number of studies have demonstrated that a room temperature proton irradiation may not be sufficient to provide an accurate estimation of the impact of the space radiation environment on detector performance. This is a result of the relationship between defect mobility and temperature, causing the performance to vary subject to the temperature history of the device from the point at which it was irradiated. Results measured using Charge Coupled Devices (CCD) irradiated at room temperature therefore tend to differ from those taken when the device was irradiated at a cryogenic temperature, more appropriate considering the operating conditions in space, impacting the prediction of in-flight performance. This paper describes the cryogenic irradiation, and subsequent annealing of an e2v technologies Swept Charge Device (SCD) CCD236 irradiated at ?35.4°C with a 10 MeV equivalent proton fluence of 5.0 × 108 protons · cm?2. The CCD236 is a large area (4.4 cm2) X-ray detector that will be flown on-board the Chandrayaan-2 and Hard X-ray Modulation Telescope spacecraft, in the Chandrayaan-2 Large Area Soft X-ray Spectrometer and the Soft X-ray Detector respectively. The SCD is readout continually in order to benefit from intrinsic dither mode clocking, leading to suppression of the surface component of the dark current and allowing the detector to be operated at warmer temperatures than a conventional CCD. The SCD is therefore an excellent choice to test and demonstrate the variation in the impact of irradiation at cryogenic temperatures in comparison to a more typical room temperature irradiation.

Gow, J. P. D.; Smith, P. H.; Pool, P.; Hall, D. J.; Holland, A. D.; Murray, N. J.

2015-01-01

169

Finger temperature controller for non-invasive blood glucose measurement  

NASA Astrophysics Data System (ADS)

Blood glucose level is an important parameter for doctors to diagnose and treat diabetes. The Near-Infra-Red (NIR) spectroscopy method is the most promising approach and this involves measurement on the body skin. However it is noted that the skin temperature does fluctuate with the environmental and physiological conditions and we found that temperature has important influences on the glucose measurement. In-vitro and in-vivo investigations on the temperature influence on blood glucose measurement have been carried out. The in-vitro results show that water temperature has significant influence on water absorption. Since 90% of blood components are water, skin temperature of measurement site has significant influence on blood glucose measurement. Also the skin temperature is related to the blood volume, blood volume inside capillary vessels changes with skin temperature. In this paper the relationship of skin temperature and signal from the skin and inside tissue was studied at different finger temperatures. Our OGTT (oral glucose tolerance test) trials results show the laser signals follow the skin temperature trend and the correlation of signal and skin temperature is much stronger than the correlation of signal and glucose concentration. A finger heater device is designed to heat and maintain the skin temperature of measurement site. The heater is controlled by an electronic circuit according to the skin temperature sensed by a thermocouple that is put close to the measurement site. In vivo trials were carried out and the results show that the skin temperature significantly influences the signal fluctuations caused by pulsate blood and the average signal value.

Zhang, Xiqin; Ting, Choon Meng; Yeo, Joon Hock

2010-11-01

170

International Workshop on Magnetic Measurements of Insertion Devices  

SciTech Connect

The International Workshop on Magnetic Measurements of Insertion Devices was held at the Advanced Photon Source, Argonne National Laboratory, on September 28--29, 1993. The workshop brought together scientists and engineers from Europe, Japan, and the United States to discuss the following topics: Special techniques for magnetic measurements of insertion devices, magnetic tolerances of the insertion devices for third generation synchrotron radiation sources, methods for and accuracy of the multipole moments measurements, magnetic sensors, among other topics. The workshop included thirteen presentations that are collected in this volume.

Not Available

1993-10-01

171

Human Response to Measured Sound Pressure Levels from Ultrasonic Devices  

Microsoft Academic Search

Measurements of noise levels were made in the vicinity of ultrasonic devices used for cleaning, welding and drilling. These devices had operating frequencies from 15000 to 80000 cps. At levels of 80-90 db subjective intolerance was manifest; above 90 db ill effects and pain began. There was indication of narrow band sensitivity at 22400-28000 cps. The greater annoyance from ultrasonic

C. P. Skillern

1965-01-01

172

Stagnation temperature measurement using thin-film platinum resistance sensors  

NASA Astrophysics Data System (ADS)

The measurement of stagnation temperature in high-speed flows is an important aspect of gas turbine engine testing. The ongoing requirement to improve the accuracy of such measurements has led to the development of probe systems that use a thin-film platinum resistance thermometer (PRT) as the sensing element. For certain aspects of engine testing this type of sensing device potentially offers superior measurement performance to the thermocouple, the temperature sensor of choice in most gas turbine applications. This paper considers the measurement performance of prototype PRT-based stagnation temperature probes, up to high-subsonic flow conditions, using passively aspirated probe heads. The relatively poor temperature recovery performance of a simply constructed probe has led to the development of a new design that is intended to reduce the impact of thermal conduction within the probe assembly. The performance of this so-called dual-skin probe has been measured through a series of tests at a range of Mach numbers, incidence angles and Reynolds numbers. The data reveal that a high probe recovery factor has been achieved with this device, and that the application of this design to engine tests would yield the measurement performance benefits of the PRT whilst requiring small levels of temperature recovery compensation.

Bonham, C.; Thorpe, S. J.; Erlund, M. N.; Stevenson, R. D.

2014-01-01

173

Research on multifunction measurement device by laser diffraction  

NASA Astrophysics Data System (ADS)

The measuring device by laser diffraction is described, It is used for measuring the Mean Spacing Sm of the Profile Irregularities, the Mean Spacing S of Local Peak of the Profile both are the parameters of the surface roughness standard, the feed rate f, the diameter of filament and the thickness of thin slice. Non-contact or on-line measurement could be realized by means of this device for measuring all parameters mentioned above (except thickness of thin slice). The device is characterized by adopting a diverging lens to expand the diffraction pattern, measuring and reading the separation of diffraction fringes using an electronic vernier calipers with numerical reading, thus reaching the purpose of measurement by means of lower precision electronic vernier calipers with numerical reading to deal with higher precision measurement.

Ma, He; Yu, Jian-Hua; Wang, Cheng-Jun; Liu, Hu-Chun

1993-09-01

174

33. BENTZEL TUBE. A CURRENT VELOCITY MEASURING DEVICE DEVELOPED AT ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. BENTZEL TUBE. A CURRENT VELOCITY MEASURING DEVICE DEVELOPED AT WES IN 1932 BY CARL E. BENTZEL. - Waterways Experiment Station, Hydraulics Laboratory, Halls Ferry Road, 2 miles south of I-20, Vicksburg, Warren County, MS

175

Experimental Semi-Device-Independent Certification of Entangled Measurements  

NASA Astrophysics Data System (ADS)

Certifying the entanglement of quantum states with Bell inequalities allows one to guarantee the security of quantum information protocols independently of imperfections in the measuring devices. Here, we present a similar procedure for witnessing entangled measurements, which play a central role in many quantum information tasks. Our procedure is termed semi-device-independent, as it uses uncharacterized quantum preparations of fixed Hilbert space dimension. Using a photonic setup, we experimentally certify an entangled measurement using only measurement statistics. We also apply our techniques to certify unentangled but nevertheless inherently quantum measurements.

Bennet, Adam; Vértesi, Tamás; Saunders, Dylan J.; Brunner, Nicolas; Pryde, G. J.

2014-08-01

176

Survey and Experimental Testing of Nongravimetric Mass Measurement Devices  

NASA Technical Reports Server (NTRS)

Documentation presented describes the design, testing, and evaluation of an accelerated gravimetric balance, a low mass air bearing oscillator of the spring-mass type, and a centrifugal device for liquid mass measurement. A direct mass readout method was developed to replace the oscillation period readout method which required manual calculations to determine mass. A protoype 25 gram capacity micro mass measurement device was developed and tested.

Oakey, W. E.; Lorenz, R.

1977-01-01

177

Method and apparatus for optical temperature measurements  

DOEpatents

A method and apparatus are provided for remotely monitoring temperature. Both method and apparatus employ a temperature probe material having an excitation-dependent emission line whose fluorescence intensity varies directly with temperature whenever excited by light having a first wavelength and whose fluorescence intensity varies inversely with temperature whenever excited by light having a second wavelength. Temperature is measured by alternatively illuminating the temperature probe material with light having the first wavelength and light having the second wavelength, monitoring the intensity of the successive emissions of the excitation-dependent emission line, and relating the intensity ratio of successive emissions to temperature.

Angel, S. Michael (Livermore, CA); Hirschfeld, Tomas B. (Livermore, CA)

1988-01-01

178

Method and apparatus for optical temperature measurements  

DOEpatents

A method and apparatus are provided for remotely monitoring temperature. Both method and apparatus employ a temperature probe material having an excitation-dependent emission line whose fluorescence intensity varies directly with temperature whenever excited by light having a first wavelength and whose fluorescence intensity varies inversely with temperature whenever excited by light having a second wavelength. Temperature is measured by alternatively illiminating the temperature probe material with light having the first wavelength and light having the second wavelength, monitoring the intensity of the successive emissions of the excitation-dependent emission line, and relating the intensity ratio of successive emissions to temperature. 3 figs.

Angel, S.M.; Hirschfeld, T.B.

1986-04-22

179

Method and apparatus for optical temperature measurement  

DOEpatents

A temperature probe and a method for using said probe for temperature measurements based on changes in light absorption by the probe. The probe comprises a first and a second optical fiber that carry light to and from the probe, and a temperature sensor material, the absorbance of which changes with temperature, through which the light is directed. Light is directed through the first optical fiber, passes through the temperature sensor material, and is transmitted by a second optical fiber from the material to a detector. Temperature-dependent and temperature-independent factors are derived from measurements of the transmitted light intensity. For each sensor material, the temperature T is a function of the ratio, R, of these factors. The temperature function f(R) is found by applying standard data analysis techniques to plots of T versus R at a series of known temperatures. For a sensor having a known temperature function f(R) and known characteristic and temperature-dependent factors, the temperature can be computed from a measurement of R. Suitable sensor materials include neodymium-doped boresilicate glass, accurate to .+-.0.5.degree. C. over an operating temperature range of about -196.degree. C. to 400.degree. C.; and a mixture of D.sub.2 O and H.sub.2 O, accurate to .+-.0.1.degree. C. over an operating range of about 5.degree. C. to 90.degree. C.

O'Rourke, Patrick E. (Martinez, GA); Livingston, Ronald R. (Aiken, SC); Prather, William S. (Augusta, GA)

1994-01-01

180

Video integrated measurement system. [Diagnostic display devices  

SciTech Connect

A Video Integrated Measurement (VIM) System is described which incorporates the use of various noninvasive diagnostic procedures (moire contourography, electromyography, posturometry, infrared thermography, etc.), used individually or in combination, for the evaluation of neuromusculoskeletal and other disorders and their management with biofeedback and other therapeutic procedures. The system provides for measuring individual diagnostic and therapeutic modes, or multiple modes by split screen superimposition, of real time (actual) images of the patient and idealized (ideal-normal) models on a video monitor, along with analog and digital data, graphics, color, and other transduced symbolic information. It is concluded that this system provides an innovative and efficient method by which the therapist and patient can interact in biofeedback training/learning processes and holds considerable promise for more effective measurement and treatment of a wide variety of physical and behavioral disorders.

Spector, B.; Eilbert, L.; Finando, S.; Fukuda, F.

1982-06-01

181

Effects of chamber pressure variation on the grid temperature in an inertial electrostatic confinement device  

Microsoft Academic Search

Inertial electrostatic confinement fusion devices are compact sources of neutrons, protons, electrons, and x rays. Such sources have many applications. Improving the efficiency of the device also increases the applications of this device. Hence a thorough understanding of the operation of this device is needed. In this paper, we study the effect of chamber pressure on the temperature of the

S. Krupakar Murali; G. A. Emmert; J. F. Santarius; G. L. Kulcinski

2010-01-01

182

In situ high-temperature characterization of AlN-based surface acoustic wave devices  

NASA Astrophysics Data System (ADS)

We report on in situ electrical measurements of surface acoustic wave delay lines based on AlN/sapphire structure and iridium interdigital transducers between 20 °C and 1050 °C under vacuum conditions. The devices show a great potential for temperature sensing applications. Burnout is only observed after 60 h at 1050 °C and is mainly attributed to the agglomeration phenomena undergone by the Ir transducers. However, despite the vacuum conditions, a significant oxidation of the AlN film is observed, pointing out the limitation of the considered structure at least at such extreme temperatures. Original structures overcoming this limitation are then proposed and discussed.

Aubert, Thierry; Bardong, Jochen; Legrani, Ouarda; Elmazria, Omar; Badreddine Assouar, M.; Bruckner, Gudrun; Talbi, Abdelkrim

2013-07-01

183

Low-cost optoelectronic devices to measure velocity of detonation  

NASA Astrophysics Data System (ADS)

Velocity of Detonation (VoD) is an important measured characteristic parameter of explosive materials. When new explosives are developed, their VoD must be determined. Devices used to measure VoD are always destroyed in the process, however replacing these devices represents a considerable cost in the characterisation of new explosives. This paper reports the design and performance of three low-cost implementations of a point-to-point VoD measurement system, two using optical fibre and a third using piezoelectric polymers (PolyVinyliDine Flouride, PVDF). The devices were designed for short charges used under controlled laboratory conditions and were tested using the common explosive 'Composition B'. These new devices are a fraction of the cost of currently available VoD sensors and show promise in achieving comparable accuracy. Their future development will dramatically reduce the cost of testing and aid the characterisation of new explosives.

Chan, Edwin M.; Lee, Vivian; Mickan, Samuel P.; Davies, Phil J.

2005-02-01

184

Implanted Blood-Pressure-Measuring Device  

NASA Technical Reports Server (NTRS)

Arterial pressure compared with ambient bodily-fluid pressure. Implanted apparatus, capable of measuring blood pressure of patient, includes differential-pressure transducer connected to pressure sensor positioned in major artery. Electrical signal is function of differential pressure between blood-pressure sensor and reference-pressure sensor transmitted through skin of patient to recorder or indicator.

Fischell, Robert E.

1988-01-01

185

MEASURING VARIATIONS IN TEMPERATURE AND PRESSURE  

E-print Network

MEASURING VARIATIONS IN TEMPERATURE AND PRESSURE A Balloon Experiment by: John Bertinetti and Chip Keating #12;Purpose of the Balloon Experiment Pressure and temperature vary with altitude: pressure;Pressure: P vs. h #12;Temperature: Exponential Curve Fit Note: this is a curve, not a line #12;Our pressure

California at Santa Cruz, University of

186

Reliability issues in human brain temperature measurement  

Microsoft Academic Search

INTRODUCTION: The influence of brain temperature on clinical outcome after severe brain trauma is currently poorly understood. When brain temperature is measured directly, different values between the inside and outside of the head can occur. It is not yet clear if these differences are 'real' or due to measurement error. METHODS: The aim of this study was to assess the

Charmaine Childs; Graham Machin

2009-01-01

187

Learning Remote Temperature Measurement in Instrumentation Laboratory  

Microsoft Academic Search

In our paper we present a laboratory temperature measuring system that can be remotely accessed by Internet. The system is based on the DS18B20 and DS1822 digital temperature sensors controlled with the aid of a microcontroller board PCB80c552. The system is used to measure and monitor the temperature in different places inside a computer. Using a web browser we can

L. Breniuc; C. G. Hab; A. Salceanu

188

CARS application in measurement of flame temperature  

NASA Astrophysics Data System (ADS)

Flame temperature distribution is very important for combustion diagnosis, but it is very hard to measure it because of the instability of flame and possible transient variability. Classical method used for measurement of flame temperature is always a contact method utilizing a thermocouple. Limitations on the use of thermocouples include long response time, disturbance on target temperature field, inelasiticity in rigorous measurement circumstance. Only coarse qualitative results can be acquired. A potential laser spectrum diagnostic technology was therefore introduced. The method of coherent anti-stokes Raman spectroscopy (CARS) in the measurement of temperature distribution was discussed using CARS theory. The design of measurement system was put forward and preliminary experiment results are shown. Theoretical CARS spectrums at 2000K were calculated utilizing the model of molecule transition in CARS process. Experimental results were compared to those of thermocouple measurement, and since results of two methods are close, feasibility of CARS application in the measurement of flame temperature was verified. Although the resolution of this method is not applicable for real-time measurement, a single measurement can be accomplished in a few nanoseconds. The resolution of temperature measurement is 5% better than results of measurement by thermocouple. Furthermore, future research is suggested to overcome the insufficiency of this method was pointed out with direction suggested.

Zhang, Hu; Dai, Jing-min

2008-10-01

189

Two-wavelength Raman imaging for non-intrusive monitoring of transient temperature in microfluidic devices  

NASA Astrophysics Data System (ADS)

The present study proposes a non-intrusive visualization technique based on two-wavelength Raman imaging for in-situ monitoring of the unsteady temperature field in microfluidic systems. The measurement principle relies on the contrasting temperature dependencies of hydrogen-bonded and non-hydrogen-bonded OH stretching modes of the water Raman band, whose intensities were simultaneously captured by two cameras equipped with corresponding bandpass filters. The temperature distributions were then determined from the intensity ratio of the simultaneously-obtained Raman images, which enables compensation for temporal fluctuation and spatial inhomogeneity of the excitation laser intensity. A calibration experiment exhibited a linear relationship between the temperature and the intensity ratio in the range 293-343?K and least-regression analysis gave an uncertainty of 1.43?K at 95% confidence level. By applying the calibration data, time series temperature distributions were quantitatively visualized in a Y-shaped milli-channel at a spatial resolution of 6.0? × ?6.0?µm2 with an acquisition time of 16.5?s. The measurement result clearly exhibited the temporal evolution of the temperature field and was compared with the values obtained by thermocouples. This paper therefore demonstrates the viability of employing the two-wavelength Raman imaging technique for temperature measurements in microfluidic devices.

Kuriyama, Reiko; Sato, Yohei

2014-09-01

190

New experimental device for infrared spectral directional emissivity measurements in a controlled environment  

NASA Astrophysics Data System (ADS)

A new experimental device for infrared spectral directional emissivity measurements in a controlled atmosphere is presented. The sample holder, which permits to measure spectral directional emissivity up to 1050K, is placed inside a stainless steel sample chamber that can be evacuated or filled with different gases. The signal detection is carried out by means of a Fourier transform infrared spectrometer. The experimental results focus on the capability of the device to perform emissivity measurements as a function of temperature, emission angle, and in situ surface state evolution. A careful study of the sample temperature homogeneity and the measurement method has been done, including the background radiation, the apparatus response function, and temperature differences between the sample and the blackbody radiator. As a consequence, a compact expression for the sample emissivity that generalizes those previously obtained for the direct radiometric measurement method is found. The error assessment shows that the main contribution to the emissivity uncertainty is related to the sample temperature. The overall uncertainty at intermediate temperature is estimated to be around 3% at short wavelengths. Emissivity measurements of Armco iron were used in order to check the accuracy of the experimental device. The experimental results show an excellent fit with direct emissivity data accessible in the literature, as well as with the theoretical emissivity obtained from the Hagen-Rubens relation.

del Campo, Leire; Pérez-Sáez, Raúl B.; Esquisabel, Xabier; Fernández, Ignacio; Tello, Manuel J.

2006-11-01

191

Precise Measurement of Process Temperature Differences  

SciTech Connect

Measurement of power in a nuclear reactor system is comparable to measurement of yield in a chemical plant or to measurement of throughput in a paper mill process. In most reactor systems power is determined by measurement of heat transferred to the coolant. In this study reactor coolant heat-rise was determined by the differential-temperature measuring circuitry of a power calculator which computed and recorded reactor power. This paper presents measurement techniques involved in determining the differential temperature and may be of parallel interest to instrument engineers in other process fields.

Kitchen, B.G.

2003-01-16

192

Temperature dependence of the properties of DBR mirrors used in surface normal optoelectronic devices  

NASA Technical Reports Server (NTRS)

The variation in the center wavelength of distributed Bragg reflectors used in optoelectronic devices, such as surface emitting lasers and Fabry-Perot modulators, is measured as the temperature of the mirrors changes over the range 25 C to 105 C. An analytic expression for the shift in center wavelength with temperature is presented. The mirrors measured are made of InP/InGaAsP, GaAs/AlAs, and Si/SiN(x). The linear shifts in center wavelength are 0.110 +/- 0.003 nm/C, 0.087 +/- 0.003 nm/C, and 0.067 +/- 0.007 nm/C for the InP/InGaAsP, GaAs/AlAs, and Si/SiN mirrors, respectively. Based on these data, the change in penetration depth with temperature is calculated.

Dudley, J. J.; Crawford, D. L.; Bowers, J. E.

1992-01-01

193

Photocurrent Measurements on a Quantum Cascade Laser Device by Fourier Transform Infrared Microscope  

NASA Astrophysics Data System (ADS)

Intersubband photocurrent in the InAs/AlSb mid-infrared quantum cascade laser (QCL) device is measured. To characterize subband energies in a fabricated and functioning QCL laser device, Fourier-transform infrared (FTIR) microscope is used to focus the probe light on the cleaved mirror of QCL. Photocurrent associated with intersubband transitions in the active layer are observed up to room temperature and the origin of peaks is identified by numerical simulation, which demonstrates the potential as a characterization tool for QCL devices.

Enobio, Eli Christopher I.; Sato, Hiroki; Ohtani, Keita; Ohno, Yuzo; Ohno, Hideo

2012-06-01

194

Sensorless temperature estimation and control of Peltier devices  

E-print Network

Peltier devices, also known as thermoelectric devices (TEDs), are solid state junctions of two dissimilar materials in which heat transfer and electrical conduction are coupled. A current running through a TED causes heat ...

Odhner, Lael Ulam, 1980-

2006-01-01

195

Measurement kernel design for compressive imaging under device constraints  

NASA Astrophysics Data System (ADS)

We look at the design of projective measurements for compressive imaging based upon image priors and device constraints. If one assumes that image patches from natural imagery can be modeled as a low rank manifold, we develop an optimality criterion for a measurement matrix based upon separating the canonical elements of the manifold prior. We then describe a stochastic search algorithm for finding the optimal measurements under device constraints based upon a subspace mismatch algorithm. The algorithm is then tested on a prototype compressive imaging device designed to collect an 8x4 array of projective measurements simultaneously. This work is based upon work supported by DARPA and the SPAWAR System Center Pacific under Contract No. N66001-11-C-4092. The views expressed are those of the author and do not reflect the official policy or position of the Department of Defense or the U.S. Government.

Shilling, Richard; Muise, Robert

2013-05-01

196

Microactuator device for integrated measurement of epithelium mechanics  

PubMed Central

Mechanical forces are among important factors that drive cellular function and organization. We present a microfabricated device with on-chip actuation for mechanical testing of single cells. An integrated immersible electrostatic actuator system is demonstrated that applies calibrated forces to cells. We conduct stretching experiments by directly applying forces to epithelial cells adhered to device surfaces functionalized with collagen. We measure mechanical properties including stiffness, hysteresis and visco-elasticity of adherent cells. PMID:22927158

Mukundan, Vikram; Nelson, W. James; Pruitt, Beth L.

2012-01-01

197

ADC's Insertion Devices and Magnetic Measurement Systems Capabilities  

NASA Astrophysics Data System (ADS)

In this paper Advance Design Consulting USA, Inc. (ADC) will discuss ADC's major improved capabilities for building Wiggler Insertion Devices, Undulator Planar Devices, Elliptical Polarizing Undulators (EPU), In-Vacuum Undulators (IVU), Cryogenically Cooled in-vacuum Undulators (CPMU), Super Conductive Undulator, and Insertion Device Magnetic Measurement Systems. ADC has designed, built and delivered Insertion Devices and Magnetic Measurement Systems to such facilities as MAX-lab (two EPUs, a Planar, and Measurement System), ALBA and ASP (Wigglers), BNL (CPMU), SSRF (two IVUs and a Measurement System), PAL (one IVU and Measurement System), NSRRC (one 4m EPU), and SRC (Planar and EPU). ADC's magnetic field measurement system is a sophisticated and sensitive machine for the measurement of magnetic fields in undulators (Planar and EPU), wigglers and in-vacuum ID units. The magnetic fields are measured using 3 axis hall-effect probes, mounted orthogonally, to a thin wand. The wand is mounted to a carriage that rides on vacuum air bearings. The base is granite. A flip coil is provided on two vertical towers with X, Y and Theta axes. Special software is provided to assist in homing, movement, and data collection and analysis.

Deyhim, A.; Kulesza, J.

2013-03-01

198

Survey and experimental testing of nongravimetric mass measurement devices  

Microsoft Academic Search

Documentation presented describes the design, testing, and evaluation of an accelerated gravimetric balance, a low mass air bearing oscillator of the spring-mass type, and a centrifugal device for liquid mass measurement. A direct mass readout method was developed to replace the oscillation period readout method which required manual calculations to determine mass. A protoype 25 gram capacity micro mass measurement

W. E. Oakey; R. Lorenz

1977-01-01

199

Nonintrusive temperature measurements on advanced turbomachinery components  

SciTech Connect

A nonintrusive, noncontacting method we developed for temperature measurements in hostile environments is well-suited for measurements on advanced turbine components. The method is not only superior to thermocouples in sufficiently difficult environments, but also is the only known method for making measurements in situations where no form of pyrometry works. We demonstrated the method, which uses laser-induced fluorescence of thermographic phosphors bonded to the component surfaces, on turbine blades and vanes in developmental turbine engines. The method is extendable to the much-higher temperatures expected inside advanced turbomachinery. Of particular note is the adaptability of the method to surface-temperature measurements on ceramics operating at high temperatures. In this temperature range, the ceramics become translucent, and surface emissivity becomes meaningless. We shall discuss the method, its advantages and limitations, recent test results on operating turbine engines, and the extension to ceramic components.

Noel, B.W. [Los Alamos National Lab., NM (United States); Turley, W.D.; Lewis, W. [EG and G Energy Measurements, Inc., Goleta, CA (United States)

1992-12-31

200

Nulling Infrared Radiometer for Measuring Temperature  

NASA Technical Reports Server (NTRS)

A nulling, self-calibrating infrared radiometer is being developed for use in noncontact measurement of temperature in any of a variety of industrial and scientific applications. This instrument is expected to be especially well-suited to measurement of ambient or near-ambient temperature and, even more specifically, for measuring the surface temperature of a natural body of water. Although this radiometer would utilize the long-wavelength infrared (LWIR) portion of the spectrum (wavelengths of 8 to 12 m), its basic principle of operation could also be applied to other spectral bands (corresponding to other temperature ranges) in which the atmosphere is transparent and in which design requirements for sensitivity and temperature-measurement accuracy could be satisfied.

Ryan, Robert

2003-01-01

201

Thermistor holder for skin-temperature measurements  

NASA Technical Reports Server (NTRS)

Sensing head of thermistor probe is supported in center area of plastic ring which has tabs so that it can be anchored in place by rubber bands or adhesive tapes. Device attaches probes to human subjects practically, reliably, and without affecting characteristics of skin segment being measured.

Greenleaf, J. E.; Williams, B. A.

1974-01-01

202

Simultaneous distributed strain and temperature measurement.  

PubMed

Brillouin-scattering-based sensors are capable of measuring either the strain or the temperature along the length of an optical fiber in a distributed fashion through measurement of the Brillouin-frequency shift. The cross sensitivity of the frequency shift to these two parameters makes it impossible to differentiate between them by measurement of the frequency shift alone. We report on a new technique that permits the simultaneous measurement of strain and temperature to resolutions of +/-178 microepsilon and +/-3.9 degrees C at a spatial resolution of 3.5 m by incorporation of the Brillouin-loss peak power with the conventional Brillouin-frequency measurement. PMID:18324040

Smith, J; Brown, A; DeMerchant, M; Bao, X

1999-09-01

203

SThM Temperature Mapping and Nonlinear Thermal Resistance Evolution With Bias on AlGaN\\/GaN HEMT Devices  

Microsoft Academic Search

Channel temperature has a strong impact on the performance of a microwave power transistor. In particular, it has a strong influence on the power gain, energetic efficiency, and reliability of the device. The thermal optimization of device geometry is therefore a key issue, together with precise measurements of temperature within the channel area. In this paper, we have used scanning

Raphal Aubry; Jean-Claude Jacquet; J. Weaver; Olivier Durand; P. Dobson; G. Mills; Marie-Antoinette di Forte-Poisson; Simone Cassette; Sylvain-Laurent Delage

2007-01-01

204

Methods of Measurement for Semiconductor Materials, Process Control, and Devices  

NASA Technical Reports Server (NTRS)

The development of methods of measurement for semiconductor materials, process control, and devices is reported. Significant accomplishments include: (1) Completion of an initial identification of the more important problems in process control for integrated circuit fabrication and assembly; (2) preparations for making silicon bulk resistivity wafer standards available to the industry; and (3) establishment of the relationship between carrier mobility and impurity density in silicon. Work is continuing on measurement of resistivity of semiconductor crystals; characterization of generation-recombination-trapping centers, including gold, in silicon; evaluation of wire bonds and die attachment; study of scanning electron microscopy for wafer inspection and test; measurement of thermal properties of semiconductor devices; determination of S-parameters and delay time in junction devices; and characterization of noise and conversion loss of microwave detector diodes.

Bullis, W. M. (ed)

1973-01-01

205

Dynamic temperature measurements with embedded optical sensors.  

SciTech Connect

This report summarizes LDRD project number 151365, %5CDynamic Temperature Measurements with Embedded Optical Sensors%22. The purpose of this project was to develop an optical sensor capable of detecting modest temperature states (<1000 K) with nanosecond time resolution, a recurring diagnostic need in dynamic compression experiments at the Sandia Z machine. Gold sensors were selected because the visible re ectance spectrum of gold varies strongly with temperature. A variety of static and dynamic measurements were performed to assess re ectance changes at di erent temperatures and pressures. Using a minimal optical model for gold, a plausible connection between static calibrations and dynamic measurements was found. With re nements to the model and diagnostic upgrades, embedded gold sensors seem capable of detecting minor (<50 K) temperature changes under dynamic compression.

Dolan, Daniel H.,; Seagle, Christopher T; Ao, Tommy

2013-10-01

206

Compact and high-efficiency device for Raman scattering measurement using optical fibers.  

PubMed

We describe the design and development of a high-efficiency optical measurement device for operation within the small bore of a high-power magnet at low temperature. For the high-efficiency measurement of light emitted from this small region, we designed a compact confocal optics with lens focusing and tilting systems, and used a piezodriven translation stage that allows micron-scale focus control of the sample position. We designed a measurement device that uses 10 m-long optical fibers in order to avoid the influence of mechanical vibration and magnetic field leakage of high-power magnets, and we also describe a technique for minimizing the fluorescence signal of optical fibers. The operation of the device was confirmed by Raman scattering measurements of monolayer graphene on quartz glass with a high signal-to-noise ratio. PMID:25430102

Mitsui, Tadashi

2014-11-01

207

Compact and high-efficiency device for Raman scattering measurement using optical fibers  

NASA Astrophysics Data System (ADS)

We describe the design and development of a high-efficiency optical measurement device for operation within the small bore of a high-power magnet at low temperature. For the high-efficiency measurement of light emitted from this small region, we designed a compact confocal optics with lens focusing and tilting systems, and used a piezodriven translation stage that allows micron-scale focus control of the sample position. We designed a measurement device that uses 10 m-long optical fibers in order to avoid the influence of mechanical vibration and magnetic field leakage of high-power magnets, and we also describe a technique for minimizing the fluorescence signal of optical fibers. The operation of the device was confirmed by Raman scattering measurements of monolayer graphene on quartz glass with a high signal-to-noise ratio.

Mitsui, Tadashi

2014-11-01

208

Magnetic Resonance Flow Velocity and Temperature Mapping of a Shape Memory Polymer Foam Device  

SciTech Connect

Interventional medical devices based on thermally responsive shape memory polymer (SMP) are under development to treat stroke victims. The goals of these catheter-delivered devices include re-establishing blood flow in occluded arteries and preventing aneurysm rupture. Because these devices alter the hemodynamics and dissipate thermal energy during the therapeutic procedure, a first step in the device development process is to investigate fluid velocity and temperature changes following device deployment. A laser-heated SMP foam device was deployed in a simplified in vitro vascular model. Magnetic resonance imaging (MRI) techniques were used to assess the fluid dynamics and thermal changes associated with device deployment. Spatial maps of the steady-state fluid velocity and temperature change inside and outside the laser-heated SMP foam device were acquired. Though non-physiological conditions were used in this initial study, the utility of MRI in the development of a thermally-activated SMP foam device has been demonstrated.

Small IV, W; Gjersing, E; Herberg, J L; Wilson, T S; Maitland, D J

2008-10-29

209

Lidar measurements of stratospheric temperature during STOIC  

NASA Astrophysics Data System (ADS)

Measurements of stratospheric temperature and density were acquired by the NASA/GSFC lidar during the Stratospheric Ozone Intercomparison Campaign (STOIC) experiment at the Jet Propulsion Laboratory Table Mountain Facility (TMF) (34.4°N, 117.7°W) in July and August 1989. Lidar temperatures, obtained on 21 nights preceding and during this experiment, are compared with temperatures derived by radiosondes, datasondes, Stratospheric Aerosol and Gas Experiment (SAGE II) satellite experiment, and National Meteorological Center (NMC) analyses. Radiosondes were flown from the TMF site as well as from San Nicholas Island (33.2°N, 119.5°W) located about 225 km southwest of TMF. Datasondes were deployed from Super-Loki rockets also launched at San Nicholas Island. SAGE II satellite temperature measurements were made within 1000 km of the Table Mountain site. NMC temperature analyses derived from the NOAA satellite measurements were interpolated to coincide in space and time with the lidar measurements. The lidar temperatures, which were derived for altitudes between 30 and 65 km, were within 2-3 K of the temperatures measured by the other sensors in the altitude range 30-45 km. Between 30 and 35 km, lidar temperatures were about 2 K cooler than those obtained from the datasondes and the NMC analyses but were about 1-2 K warmer than those obtained from the radiosonde. These differences may be due to the time difference between the measurements as well as possible nonnegligible aerosol scattering near 30 km. Near and above the stratopause the temperature differences increased to 3-8 K. Lidar temperature profiles also show small-scale variations possibly caused by wave activity.

Ferrare, R. A.; McGee, T. J.; Whiteman, D.; Burris, J.; Owens, M.; Butler, J.; Barnes, R. A.; Schmidlin, F.; Komhyr, W.; Wang, P. H.; McCormick, M. P.; Miller, A. J.

1995-05-01

210

Use of piezoelectric multicomponent force measuring devices in fluid mechanics  

NASA Technical Reports Server (NTRS)

The characterisitics of piezoelectric multicomponent transducers are discussed, giving attention to the advantages of quartz over other materials. The main advantage of piezoelectric devices in aerodynamic studies is their ability to indicate rapid changes in the values of physical parameters. Problems in the accuracy of measurments by piezoelectric devices can be overcome by suitable design approaches. A practical example is given of how such can be utilized to measure rapid fluctuations of fluid forces exerted on a circular cylinder mounted in a water channel.

Richter, A.; Stefan, K.

1979-01-01

211

Experimental measurement-device-independent quantum key distribution.  

PubMed

Quantum key distribution is proven to offer unconditional security in communication between two remote users with ideal source and detection. Unfortunately, ideal devices never exist in practice and device imperfections have become the targets of various attacks. By developing up-conversion single-photon detectors with high efficiency and low noise, we faithfully demonstrate the measurement-device-independent quantum-key-distribution protocol, which is immune to all hacking strategies on detection. Meanwhile, we employ the decoy-state method to defend attacks on a nonideal source. By assuming a trusted source scenario, our practical system, which generates more than a 25 kbit secure key over a 50 km fiber link, serves as a stepping stone in the quest for unconditionally secure communications with realistic devices. PMID:24116758

Liu, Yang; Chen, Teng-Yun; Wang, Liu-Jun; Liang, Hao; Shentu, Guo-Liang; Wang, Jian; Cui, Ke; Yin, Hua-Lei; Liu, Nai-Le; Li, Li; Ma, Xiongfeng; Pelc, Jason S; Fejer, M M; Peng, Cheng-Zhi; Zhang, Qiang; Pan, Jian-Wei

2013-09-27

212

Experimental Measurement-Device-Independent Quantum Key Distribution  

NASA Astrophysics Data System (ADS)

Quantum key distribution is proven to offer unconditional security in communication between two remote users with ideal source and detection. Unfortunately, ideal devices never exist in practice and device imperfections have become the targets of various attacks. By developing up-conversion single-photon detectors with high efficiency and low noise, we faithfully demonstrate the measurement-device-independent quantum-key-distribution protocol, which is immune to all hacking strategies on detection. Meanwhile, we employ the decoy-state method to defend attacks on a nonideal source. By assuming a trusted source scenario, our practical system, which generates more than a 25 kbit secure key over a 50 km fiber link, serves as a stepping stone in the quest for unconditionally secure communications with realistic devices.

Liu, Yang; Chen, Teng-Yun; Wang, Liu-Jun; Liang, Hao; Shentu, Guo-Liang; Wang, Jian; Cui, Ke; Yin, Hua-Lei; Liu, Nai-Le; Li, Li; Ma, Xiongfeng; Pelc, Jason S.; Fejer, M. M.; Peng, Cheng-Zhi; Zhang, Qiang; Pan, Jian-Wei

2013-09-01

213

Fast Internal Temperature Measurements in PBX9501  

NASA Astrophysics Data System (ADS)

We have made spatially and temporally resolved temperature measurements internal to a thermal explosion in PBX9501. These measurements are made both by thermocouples with corrections applied to compensate for the thermocouple response time and with optical pyrometry. Our original goals were to test our kinetic model over a broader range of temperatures, to look for evidence of any late endotherms during final self heating, and to study the transition between ignition and ignition propagation. This meant we needed to be able to follow temperatures later into reaction (meaning further in time and closer to the ignition point). Our previous limit was 16ms prior to ignition limited only by the sampling rate on the logger. In order to sample faster, we switched to a direct voltage reading of the thermocouples and added fiber optic temperature measurements. In this talk, I will discuss our current capabilities for controlling and measuring the development of an ignition within a piece of heated PBX9501.

Smilowitz, Laura

2005-07-01

214

Microcalorimetry: Wide Temperature Range, High Field, Small Sample Measurements  

NASA Astrophysics Data System (ADS)

We have used Si micromachining techniques to fabricate devices for measuring specific heat or other calorimetric signals from microgram-quantity samples over a temperature range from 1 to 900K in magnetic fields to date up to 8T. The devices are based on a relatively robust silicon nitride membrane with thin film heaters and thermometers. Different types of thermometers are used for different purposes and in different temperature ranges. These devices are particularly useful for thin film samples (typically 200-400 nm thick at present) deposited directly onto the membrane through a Si micromachined evaporation mask. They have also been used for small single crystal samples attached by conducting grease or solder, and for powder samples dissolved in a solvent and dropped onto devices. The measurement technique used (relaxation method) is particularly suited to high field measurements because the thermal conductance can be measured once in zero field and is field independent, while the time constant of the relaxation does not depend on thermometer calibration. Present development efforts include designs which show promise for time-resolved calorimetry measurements of biological samples in small amounts of water. Samples measured to date include amorphous magnetic thin films (a-TbFe2 and giant negative magnetoresistance a-Gd-Si alloys), empty and filled fullerenes (C_60, K_3C_60, C_82, La@C_82, C_84, and Sc_2@C_84), single crystal manganites (La_1-xSr_xMnO_3), antiferromagnetic multilayers (NiO/CoO, NiO/MgO, and CoO/MgO), and nanoparticle magnetic materials (CoO in a Ag matrix).

Hellman, Frances

2000-03-01

215

Boron Arsenide and Boron Phosphide for High Temperature and Luminescent Devices. [semiconductor devices - crystal growth/crystal structure  

NASA Technical Reports Server (NTRS)

The crystal growth of boron arsenide and boron phosphide in the form of bulk crystals and epitaxial layers on suitable substrates is discussed. The physical, chemical, and electrical properties of the crystals and epitaxial layers are examined. Bulk crystals of boron arsenide were prepared by the chemical transport technique, and their carrier concentration and Hall mobility were measured. The growth of boron arsenide crystals from high temperature solutions was attempted without success. Bulk crystals of boron phosphide were also prepared by chemical transport and solution growth techniques. Techniques required for the fabrication of boron phosphide devices such as junction shaping, diffusion, and contact formation were investigated. Alloying techniques were developed for the formation of low-resistance ohmic contacts to boron phosphide. Four types of boron phosphide devices were fabricated: (1) metal-insulator-boron phosphide structures, (2) Schottky barriers; (3) boron phosphide-silicon carbide heterojunctions; and (4) p-n homojunctions. Easily visible red electroluminescence was observed from both epitaxial and solution grown p-n junctions.

Chu, T. L.

1975-01-01

216

Temperature structure parameter measurements using differential temperature sensors  

Microsoft Academic Search

The comparison of C {infT\\/sup2} estimates in the atmospheric boundary layer, from spectral and differential temperature (delta T) measurements, is discussed. Measurements of C {infT\\/sup2} using these two methods are compared and the differences between the two are shown to be due to low-frequency enhancement of the delta T spectrum. Possible explanations for this effect are considered and attention is

T. J. Moulsley; D. N. Asimakopoulos; R. S. Cole; S. J. Caughey; B. A. Crease

1982-01-01

217

Temperature structure parameter measurements using differential temperature sensors  

Microsoft Academic Search

The comparison of CinfTsup2 estimates in the atmospheric boundary layer, from spectral and differential temperature (dT) measurements, is discussed. Measurements of CinfTsup2 using these two methods are compared and the differences between the two are shown to be due to low-frequency enhancement of the dT spectrum. Possible explanations for this effect are considered and attention is drawn to the significance

T. J. Moulsley; D. N. Asimakopoulos; R. S. Cole; S. J. Caughey; B. A. Crease

1982-01-01

218

Floating Probe Assembly for Measuring Temperature of Water  

NASA Technical Reports Server (NTRS)

A floating apparatus denoted a temperature probe aquatic suspension system (TPASS) has been developed for measuring the temperature of an ocean, lake, or other natural body of water at predetermined depths. Prior instruments built for the same purpose were found to give inaccurate readings because the apparatuses themselves significantly affected the temperatures of the water in their vicinities. The design of the TPASS is intended to satisfy a requirement to minimize the perturbation of the temperatures to be measured. The TPASS includes a square-cross-section aluminum rod 28 in. (=71 cm) long with floats attached at both ends. Each float includes five polystyrene foam disks about 3/4 in.(=1.9 cm) thick and 2.5 in. (=6.4 cm) in diameter. The disks are stacked to form cylinders, bolted to the rod, and covered with hollow plastic sleeves. A metal sleeve is clamped to the middle of the aluminum rod, from whence it hangs down into the water. Temperature probes (which can be thermocouples, thermistors, or resistance temperature devices) are placed within the sleeve at the desired measurement depths. Wires from the temperature probes are routed to the input terminals of a data logger.

Stewart, Randy; Ruffin, Clyde

2002-01-01

219

Floating Probe Assembly for Measuring Temperature of Water  

NASA Technical Reports Server (NTRS)

A floating apparatus denoted a temperature probe aquatic suspension system (TPASS) has been developed for measuring the temperature of an ocean, lake, or other natural body of water at predetermined depths. Prior instruments built for the same purpose were found to give inaccurate readings because the apparatuses themselves significantly affected the temperatures of the water in their vicinities. The design of the TPASS is intended to satisfy a requirement to minimize the perturbation of the temperatures to be measured. The TPASS includes a square-cross-section aluminum rod 28 in. (approx. = 71 cm) long with floats attached at both ends. Each float includes five polystyrene foam disks about 3/4 in. (approx. = 1.9 cm) thick and 2.5 in. (approx. = 6.4 cm) in diameter. The disks are stacked to form cylinders, bolted to the rod, and covered with hollow plastic sleeves. A metal sleeve is clamped to the middle of the aluminum rod, from whence it hangs down into the water. Temperature probes (which can be thermocouples, thermistors, or resistance temperature devices) are placed within the sleeve at the desired measurement depths. Wires from the temperature probes are routed to the input terminals of a data logger. This work was done by Randy

Selinsky, T.; Stewart, Randy; Ruffin, Clyde

2002-01-01

220

Electrical annealing and temperature dependent transversal conduction in multilayer reduced graphene oxide films for solid-state molecular devices.  

PubMed

The transversal conductance through thin multi-layered films of reduced graphene oxide was studied as a function of temperature in a solid-state device setup designed for molecular electronic measurements. Upon cooling to cryogenic temperatures, the resistivity of the films increased by about three orders of magnitude compared to the value at room temperature, and this temperature dependence was described by a variable range hopping model. Above a certain threshold voltage the films could be annealed electrically at low temperatures. This electrical annealing resulted in a dramatic decrease in resistivity by up to four orders of magnitude. Upon reheating, the conductivity of the annealed films displayed an almost negligible temperature dependence. These results are promising for the application of reduced graphene oxide as a soft top-contact layer for molecular monolayer devices in the solid-state. PMID:22964774

Hauptmann, Jonas Rahlf; Li, Tao; Petersen, Søren; Nygård, Jesper; Hedegård, Per; Bjørnholm, Thomas; Laursen, Bo W; Nørgaard, Kasper

2012-11-01

221

MISSE 1 and 2 Tray Temperature Measurements  

NASA Technical Reports Server (NTRS)

The Materials International Space Station Experiment (MISSE 1 & 2) was deployed August 10,2001 and retrieved July 30,2005. This experiment is a co-operative endeavor by NASA-LaRC. NASA-GRC, NASA-MSFC, NASA-JSC, the Materials Laboratory at the Air Force Research Laboratory, and the Boeing Phantom Works. The objective of the experiment is to evaluate performance, stability, and long term survivability of materials and components planned for use by NASA and DOD on future LEO, synchronous orbit, and interplanetary space missions. Temperature is an important parameter in the evaluation of space environmental effects on materials. The MISSE 1 & 2 had autonomous temperature data loggers to measure the temperature of each of the four experiment trays. The MISSE tray-temperature data loggers have one external thermistor data channel, and a 12 bit digital converter. The MISSE experiment trays were exposed to the ISS space environment for nearly four times the nominal design lifetime for this experiment. Nevertheless, all of the data loggers provided useful temperature measurements of MISSE. The temperature measurement system has been discussed in a previous paper. This paper presents temperature measurements of MISSE payload experiment carriers (PECs) 1 and 2 experiment trays.

Harvey, Gale A.; Kinard, William H.

2006-01-01

222

Comparison Measurements of Silicon Carbide Temperature Monitors  

SciTech Connect

As part of the efforts initiated through the Advanced Test Reactor (ATR) National Scientific User Facility (NSUF) program to make Silicon Carbide (SiC) temperature monitors available, a capability was developed at the Idaho National Laboratory (INL) to complete post-irradiation evaluations of these monitors. INL selected the resistance measurement approach for detecting peak irradiation temperature from SiC temperature monitors. To demonstrate this new capability, comparison measurements were completed by INL and Oak Ridge National Laboratory (ORNL) on identical samples subjected to identical irradiation conditions. Results reported in this paper indicate that the resistance measurement approach can yield similar peak irradiation temperatures if appropriate equipment is used and appropriate procedures are followed.

J. L. Rempe; K. G. Condie; D. L. Knudson; L. L. Snead

2010-06-01

223

Method and apparatus for measuring low currents in capacitance devices  

DOEpatents

A method and apparatus for measuring subnanoampere currents in capacitance devices is reported. The method is based on a comparison of the voltages developed across the capacitance device with that of a reference capacitor in which the current is adjusted by means of a variable current source to produce a stable voltage difference. The current varying means of the variable current source is calibrated to provide a read out of the measured current. Current gain may be provided by using a reference capacitor which is larger than the device capacitance with a corresponding increase in current supplied through the reference capacitor. The gain is then the ratio of the reference capacitance to the device capacitance. In one illustrated embodiment, the invention makes possible a new type of ionizing radiation dose-rate monitor where dose-rate is measured by discharging a reference capacitor with a variable current source at the same rate that radiation is discharging an ionization chamber. The invention eliminates high-megohm resistors and low current ammeters used in low-current measuring instruments.

Kopp, M.K.; Manning, F.W.; Guerrant, G.C.

1986-06-04

224

IN SITU FIELD PORTABLE FINE PARTICLE MEASURING DEVICE  

EPA Science Inventory

The report describes the design, development, and testing of an in situ fine particle measuring device--the Fine Particle Stack Spectrometer System (FPSSS). It is a laser-fed optical system with detection by near-forward light scattering. Sample volume is established by a high-re...

225

Blood damage measures for ventricular assist device modeling  

E-print Network

Blood damage measures for ventricular assist device modeling Dhruv Arora1, Marek Behr1 and Matteo challenge that needs to be addressed in the design phase of blood pumps is the elevated level of shear stress, and the hemolysis response of the red blood cells, which depends on both the dose and time

Natelson, Douglas

226

Comparison of module temperature measurement methods  

Microsoft Academic Search

Aim of this study is to improve the prediction of electrical energy yield especially for PV modules based on thin film technologies. Problems with deficient power prediction of PV power plants have manifold reasons: One of the easy accessible is the measurement of NOCT (nominal operation cell temperature). Deviations of NOCTs measured have a direct influence of the yield predicted

Stefan Krauter; Alexander Preiss

2009-01-01

227

21 CFR 886.1430 - Ophthalmic contact lens radius measuring device.  

Code of Federal Regulations, 2010 CFR

...device. (a) Identification. An ophthalmic contact lens radius measuring device is an AC-powered device that is a microscope and dial gauge intended to measure the radius of a contact lens. (b) Classification. Class I (general...

2010-04-01

228

21 CFR 886.1430 - Ophthalmic contact lens radius measuring device.  

Code of Federal Regulations, 2014 CFR

...device. (a) Identification. An ophthalmic contact lens radius measuring device is an AC-powered device that is a microscope and dial gauge intended to measure the radius of a contact lens. (b) Classification. Class I (general...

2014-04-01

229

21 CFR 886.1430 - Ophthalmic contact lens radius measuring device.  

Code of Federal Regulations, 2011 CFR

...device. (a) Identification. An ophthalmic contact lens radius measuring device is an AC-powered device that is a microscope and dial gauge intended to measure the radius of a contact lens. (b) Classification. Class I (general...

2011-04-01

230

21 CFR 886.1430 - Ophthalmic contact lens radius measuring device.  

Code of Federal Regulations, 2012 CFR

...device. (a) Identification. An ophthalmic contact lens radius measuring device is an AC-powered device that is a microscope and dial gauge intended to measure the radius of a contact lens. (b) Classification. Class I (general...

2012-04-01

231

21 CFR 886.1430 - Ophthalmic contact lens radius measuring device.  

Code of Federal Regulations, 2013 CFR

...device. (a) Identification. An ophthalmic contact lens radius measuring device is an AC-powered device that is a microscope and dial gauge intended to measure the radius of a contact lens. (b) Classification. Class I (general...

2013-04-01

232

Method measuring oxygen tension and transport within subcutaneous devices.  

PubMed

Cellular therapies hold promise to replace the implantation of whole organs in the treatment of disease. For most cell types, in vivo viability depends on oxygen delivery to avoid the toxic effects of hypoxia. A promising approach is the in situ vascularization of implantable devices which can mediate hypoxia and improve both the lifetime and utility of implanted cells and tissues. Although mathematical models and bulk measurements of oxygenation in surrounding tissue have been used to estimate oxygenation within devices, such estimates are insufficient in determining if supplied oxygen is sufficient for the entire thickness of the implanted cells and tissues. We have developed a technique in which oxygen-sensitive microparticles (OSMs) are incorporated into the volume of subcutaneously implantable devices. Oxygen partial pressure within these devices can be measured directly in vivo by an optical probe placed on the skin surface. As validation, OSMs have been incorporated into alginate beads, commonly used as immunoisolation devices to encapsulate pancreatic islet cells. Alginate beads were implanted into the subcutaneous space of Sprague–Dawley rats. Oxygen transport through beads was characterized from dynamic OSM signals in response to changes in inhaled oxygen. Changes in oxygen dynamics over days demonstrate the utility of our technology. PMID:25162910

Weidling, John; Sameni, Sara; Lakey, Jonathan R T; Botvinick, Elliot

2014-08-01

233

Time Delay Neural Network Applied for Compensation of Temperature Sensors Nonlinear Dynamics on Hysteresis Measurements  

Microsoft Academic Search

There exists many kinds of technologies and sensors for measuring temperature, however, two of the most common types of sensors are thermocouples and thermistors. These sensors have dynamical response to a temperature change in the surroundings, and also have nonlinearities in the mapping between temperature and electrical signal at their output. When dealing with the characterization of thermal hysteretic devices,

F. Simas; L. Alberto; L. de Almeida

2007-01-01

234

Graphene, a material for high temperature devices intrinsic carrier density, carrier  

E-print Network

Graphene, a material for high temperature devices ­ intrinsic carrier density, carrier drift 3.87 3 106 cm22 K22 ?T2 ), carrier drift velocity, and G mode phonon energy of graphene devices and their temperature dependencies up to 2400 K. Our results show intrinsic carrier density of graphene is an order

Wang, Wei Hua

235

Comparative analysis of selected exhaled breath biomarkers obtained with two different temperature-controlled devices  

PubMed Central

Background The collection of exhaled breath condensate (EBC) is a suitable and non-invasive method for evaluation of airway inflammation. Several studies indicate that the composition of the condensate and the recovery of biomarkers are affected by physical characteristics of the condensing device and collecting circumstances. Additionally, there is an apparent influence of the condensing temperature, and often the level of detection of the assay is a limiting factor. The ECoScreen2 device is a new, partly single-use disposable system designed for studying different lung compartments. Methods EBC samples were collected from 16 healthy non-smokers by using the two commercially available devices ECoScreen2 and ECoScreen at a controlled temperature of -20°C. EBC volume, pH, NOx, LTB4, PGE2, 8-isoprostane and cys-LTs were determined. Results EBC collected with ECoScreen2 was less acidic compared to ECoScreen. ECoScreen2 was superior concerning condensate volume and detection of biomarkers, as more samples were above the detection limit (LTB4 and PGE2) or showed higher concentrations (8-isoprostane). However, NOx was detected only in EBC sampled by ECoScreen. Conclusion ECoScreen2 in combination with mediator specific enzyme immunoassays may be suitable for measurement of different biomarkers. Using this equipment, patterns of markers can be assessed that are likely to reflect the complex pathophysiological processes in inflammatory respiratory disease. PMID:19948050

2009-01-01

236

Methods for measuring acoustic power of an ultrasonic neurosurgical device.  

PubMed

Measurement of the acoustic power in high-energy ultrasonic devices is complex due to occurrence of the strong cavitation in front of the sonotrode tip. In our research we used three methods for characterization of our new ultrasonic probe for neuroendoscopic procedures. The first method is based on the electromechanical characterization of the device measuring the displacement of the sonotrode tip and input electrical impedance around excitation frequency with different amounts of the applied electrical power The second method is based on measuring the spatial pressure magnitude distribution of an ultrasound surgical device produced in an anechoic tank. The acoustic reciprocity principle is used to determinate the derived acoustic power of equivalent ultrasound sources at frequency components present in the spectrum of radiated ultrasonic waves. The third method is based on measuring the total absorbed acoustic power in the restricted volume of water using the calorimetric method. In the electromechanical characterization, calculated electroacoustic efficiency factor from equivalent electrical circuits is between 40-60%, the same as one obtained measuring the derived acoustic power in an anechoic tank when there is no cavitation. When cavitation activity is present in the front of the sonotrode tip the bubble cloud has a significant influence on the derived acoustic power and decreases electroacoustic efficiency. The measured output acoustic power using calorimetric method is greater then derived acoustic power, due to a large amount of heat energy released in the cavitation process. PMID:21648319

Petosi?, Antonio; Ivancevi?, Bojan; Svilar, Dragoljub; Stimac, Tihomir; Paladino, Josip; Oreskovi?, Darko; Jurjevi?, Ivana; Klarica, Marijan

2011-01-01

237

High temperature optical strain measurement system  

NASA Technical Reports Server (NTRS)

A high temperature strain measurement system being developed at the NASA Lewis Research Center utilizes laser speckle shift relations to measure strain components on the surface of a hot specimen in near real time. Features of this system include a totally noncontacting measurement capability and a rotatable gauge axis, allowing an optical rosette to be implemented and principal strains to be determined. Preliminary results and background work are presented.

Lant, Christian T.

1988-01-01

238

Measurements of Wall Recycling Coefficient in the HANBIT Mirror Device  

SciTech Connect

Wall recycling and results of ICRH discharge in the HANBIT mirror device are presented. The amount of gas loading due to recycling from the wall and recycling coefficient are estimated quantitatively by the time evolution of the pressures in each region of the HANBIT mirror device during plasma discharges. These measured pressures are compared with a model calculation made in terms of a coupled set of rate equations. Also we introduce a gas recycling model based on atomic and molecular processes. In this model, enhancement of fueling due to the recycling is evaluated on the basis of the calculated probabilities of neutral and ion production by using the rate coefficients of these reactions.

Seo, D.C.; Na, H.K.; Yoon, J.S.; Yoon, S.W. [Korea Basic Science Institute (Korea, Republic of)

2005-01-15

239

Assembly for electrical conductivity measurements in the piston cylinder device  

DOEpatents

An assembly apparatus for measurement of electrical conductivity or other properties of a sample in a piston cylinder device wherein pressure and heat are applied to the sample by the piston cylinder device. The assembly apparatus includes a body, a first electrode in the body, the first electrode operatively connected to the sample, a first electrical conductor connected to the first electrode, a washer constructed of a hard conducting material, the washer surrounding the first electrical conductor in the body, a second electrode in the body, the second electrode operatively connected to the sample, and a second electrical conductor connected to the second electrode.

Watson, Heather Christine (Dublin, CA); Roberts, Jeffrey James (Livermore, CA)

2012-06-05

240

Measurements of fuel thermal properties at high temperatures  

SciTech Connect

This paper describes approaches for measuring the beat capacity and thermal diffusivity for mixed oxide fuels. The authors set up a drop calorimeter device to perform enthalpy measurements on uranium-plutonium oxide and other types of plutonium-based fuel up to 3000[degrees]C. The induction heating is made using a sealed tungsten rhenium capsule to contain the fuel. A sample temperature is measured by optical pyrometers, in the black body well of the capsule. Then, the capsule is dropped into very sensitive detectors that plot the transmitted energy until the apparatus returns to its regulation temperature. Heat capacity is obtained from derivation of the enthalpy curve. The thermal diffusivity is determined by the laser flash method.

Gotta, M.J.; Philipponneau, Y. (Commissariat a l'Energie Atomique, Saint-Paul-les-Durance (France))

1992-01-01

241

40 CFR 90.309 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2014 CFR

...2013-07-01 true Engine intake air temperature measurement. 90.309 Section 90...Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...cleaner, for most engines.) (b) The temperature measurements must be accurate to...

2014-07-01

242

40 CFR 90.309 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Engine intake air temperature measurement. 90.309 Section 90...Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...cleaner, for most engines.) (b) The temperature measurements must be accurate to...

2010-07-01

243

40 CFR 90.309 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Engine intake air temperature measurement. 90.309 Section 90...Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...cleaner, for most engines.) (b) The temperature measurements must be accurate to...

2012-07-01

244

40 CFR 90.309 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Engine intake air temperature measurement. 90.309 Section 90...Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...cleaner, for most engines.) (b) The temperature measurements must be accurate to...

2013-07-01

245

40 CFR 90.309 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Engine intake air temperature measurement. 90.309 Section 90...Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...cleaner, for most engines.) (b) The temperature measurements must be accurate to...

2011-07-01

246

Turbine gas temperature measurement and control system  

NASA Technical Reports Server (NTRS)

A fluidic Turbine Inlet Gas Temperature (TIGIT) Measurement and Control System was developed for use on a Pratt and Whitney Aircraft J58 engine. Based on engine operating requirements, criteria for high temperature materials selection, system design, and system performance were established. To minimize development and operational risk, the TIGT control system was designed to interface with an existing Exhaust Gas Temperature (EGT) Trim System and thereby modulate steady-state fuel flow to maintain a desired TIGT level. Extensive component and system testing was conducted including heated (2300F) vibration tests for the fluidic sensor and gas sampling probe, temperature and vibration tests on the system electronics, burner rig testing of the TIGT measurement system, and in excess of 100 hours of system testing on a J58 engine. (Modified author abstract)

Webb, W. L.

1973-01-01

247

EFFECTIVE ULTRAVIOLET IRRADIANCE MEASUREMENTS FROM ARTIFICIAL TANNING DEVICES IN GREECE.  

PubMed

Artificial tanning remains very popular worldwide, despite the International Agency for Research on Cancer classification of ultraviolet (UV) radiation from sunbeds as 'carcinogenic to humans'. Greek Atomic Energy Commission has initiated a surveillance action of the artificial tanning devices in Greece in order to record the effective irradiance levels from the sunbeds and to inform and synchronise the domestic artificial tanning business sector with the requirements of the European Standard EN 60335-2-27:2010. In this direction, in situ measurements of UV emissions from sunbeds in solaria businesses all over Greece were performed from October 2013 until July 2014, with a radiometer and a portable single-monochromator spectrophotometer. Analysis of the measurements' results revealed that effective irradiance in ?60 % of the measured sunbeds exceeded the 0.3 W m(-2) limit value set by EN 60335-2-27:2010 and only 20 % of the devices could be categorised as UV type 3. PMID:25468991

Petri, Aspasia; Karabetsos, Efthymios

2014-12-01

248

Measurement of wire electrode temperature in WEDM  

Microsoft Academic Search

Wire temperature is an important parameter in the wire electro-discharge machining (WEDM) process because overheating of the\\u000a wire can cause the wire to break. It is difficult, however, to measure the wire temperature directly under the condition that\\u000a the wire is emerged in water and surrounded by the workpiece. Only mathematical analyses by now have been reported to determine\\u000a such

Fuzhu Han; Gang Cheng; Zhijing Feng; Isago Soichiro

2009-01-01

249

Apparatus and method for high temperature viscosity and temperature measurements  

DOEpatents

A probe for measuring the viscosity and/or temperature of high temperature liquids, such as molten metals, glass and similar materials comprises a rod which is an acoustical waveguide through which a transducer emits an ultrasonic signal through one end of the probe, and which is reflected from (a) a notch or slit or an interface between two materials of the probe and (b) from the other end of the probe which is in contact with the hot liquid or hot melt, and is detected by the same transducer at the signal emission end. To avoid the harmful effects of introducing a thermally conductive heat sink into the melt, the probe is made of relatively thermally insulative (non-heat-conductive) refractory material. The time between signal emission and reflection, and the amplitude of reflections, are compared against calibration curves to obtain temperature and viscosity values.

Balasubramaniam, Krishnan (Mississippi State, MS); Shah, Vimal (Houston, TX); Costley, R. Daniel (Mississippi State, MS); Singh, Jagdish P. (Mississippi State, MS)

2001-01-01

250

A simple device for dielectric spectroscopy of polymers with temperature regulation close to 300 K based on a Peltier junction.  

PubMed

We present a simple thermostat device for performing dielectric spectroscopy measurements on polymers close to their glass transition temperature. By using a vacuum chamber containing a Peltier junction with its regulator, we show that a very simple setup yields a temperature accuracy which is good enough for accurate studies of polymer dielectric properties. This technique is also more cost effective than standard setups using cryogenic fluids. PMID:22559545

Raihane, A; Tourbot, R; Ladieu, F; L'Hôte, D

2012-04-01

251

Temperature measurements of shock-compressed deuterium  

SciTech Connect

The authors measured the temperatures of single and double-shocked D{sub 2} and H{sub 2} up to 85 GPa (0.85 Mbar) and 5,200 K. While single shock temperatures, at pressures to 23 GPa, agree well with previous models, the double shock temperatures are as much as 40% lower than predicted. This is believed to be caused by molecular dissociation, and a new model of the hydrogen EOS at extreme conditions has been developed which correctly predicts their observations. These data and model have important implications for programs which use condensed-phase hydrogen in implosion systems.

Holmes, N.C.; Ross, M.; Nellis, W.J.

1994-11-01

252

Accuracy analysis of the space shuttle solid rocket motor profile measuring device  

NASA Technical Reports Server (NTRS)

The Profile Measuring Device (PMD) was developed at the George C. Marshall Space Flight Center following the loss of the Space Shuttle Challenger. It is a rotating gauge used to measure the absolute diameters of mating features of redesigned Solid Rocket Motor field joints. Diameter tolerance of these features are typically + or - 0.005 inches and it is required that the PMD absolute measurement uncertainty be within this tolerance. In this analysis, the absolute accuracy of these measurements were found to be + or - 0.00375 inches, worst case, with a potential accuracy of + or - 0.0021 inches achievable by improved temperature control.

Estler, W. Tyler

1989-01-01

253

Universal measurement device for electronic watches and small clocks  

NASA Astrophysics Data System (ADS)

The project and the device set up for performing automatic measurements are described. The system development involved: a specially designed acquisition card, a standard personal computer and specific management programs. It is designed as laboratory equipment and is able to perform most of measurements required by electronic watchmaking industry such as current/consumption measurements, frequency, torque, motor pulses generation. Versions meeting specific production testing needs at reasonable costs can be developed. For after sale servicing, it is possible to deliver a diskette giving all parameters needed for a specific movement, avoiding changes in hardware.

Vermot, Michel

254

Calibrating X-ray Imaging Devices for Accurate Intensity Measurement  

SciTech Connect

The purpose of the project presented is to develop methods to accurately calibrate X-ray imaging devices. The approach was to develop X-ray source systems suitable for this endeavor and to develop methods to calibrate solid state detectors to measure source intensity. NSTec X-ray sources used for the absolute calibration of cameras are described, as well as the method of calibrating the source by calibrating the detectors. The work resulted in calibration measurements for several types of X-ray cameras. X-ray camera calibration measured efficiency and efficiency variation over the CCD. Camera types calibrated include: CCD, CID, back thinned (back illuminated), front illuminated.

Haugh, M. J.

2011-07-28

255

Dual neutron flux/temperature measurement sensor  

DOEpatents

Simultaneous measurement of neutron flux and temperature is provided by a single sensor which includes a phosphor mixture having two principal constituents. The first constituent is a neutron sensitive 6LiF and the second is a rare-earth activated Y203 thermophosphor. The mixture is coated on the end of a fiber optic, while the opposite end of the fiber optic is coupled to a light detector. The detected light scintillations are quantified for neutron flux determination, and the decay is measured for temperature determination.

Mihalczo, John T. (Oak Ridge, TN); Simpson, Marc L. (Knoxville, TN); McElhaney, Stephanie A. (Oak Ridge, TN)

1994-01-01

256

Non-contact temperature measurement requirements  

NASA Technical Reports Server (NTRS)

The Marshall Space Flight Center is involved with levitation experiments for Spacelab, Space Station, and drop tube/tower operations. These experiments have temperature measurement requirements, that of course must be non-contact in nature. The experiment modules involved are the Acoustic Levitator Furnace (ALF), and the Modular Electromagnetic Levitator (MEL). User requirements of the ALF and drop tube are presented. The center also has temperature measurement needs that are not microgravity experiment oriented, but rather are related to the propulsion system for the STS. This requirement will also be discussed.

Higgins, D. B.; Witherow, W. K.

1989-01-01

257

Dual neutron flux/temperature measurement sensor  

DOEpatents

Simultaneous measurement of neutron flux and temperature is provided by a single sensor which includes a phosphor mixture having two principal constituents. The first constituent is a neutron sensitive 6LiF and the second is a rare-earth activated Y203 thermophosphor. The mixture is coated on the end of a fiber optic, while the opposite end of the fiber optic is coupled to a light detector. The detected light scintillations are quantified for neutron flux determination, and the decay is measured for temperature determination. 3 figs.

Mihalczo, J.T.; Simpson, M.L.; McElhaney, S.A.

1994-10-04

258

Epidermal photonic devices for quantitative imaging of temperature and thermal transport characteristics of the skin.  

PubMed

Characterization of temperature and thermal transport properties of the skin can yield important information of relevance to both clinical medicine and basic research in skin physiology. Here we introduce an ultrathin, compliant skin-like, or 'epidermal', photonic device that combines colorimetric temperature indicators with wireless stretchable electronics for thermal measurements when softly laminated on the skin surface. The sensors exploit thermochromic liquid crystals patterned into large-scale, pixelated arrays on thin elastomeric substrates; the electronics provide means for controlled, local heating by radio frequency signals. Algorithms for extracting patterns of colour recorded from these devices with a digital camera and computational tools for relating the results to underlying thermal processes near the skin surface lend quantitative value to the resulting data. Application examples include non-invasive spatial mapping of skin temperature with milli-Kelvin precision (±50?mK) and sub-millimetre spatial resolution. Demonstrations in reactive hyperaemia assessments of blood flow and hydration analysis establish relevance to cardiovascular health and skin care, respectively. PMID:25234839

Gao, Li; Zhang, Yihui; Malyarchuk, Viktor; Jia, Lin; Jang, Kyung-In; Webb, R Chad; Fu, Haoran; Shi, Yan; Zhou, Guoyan; Shi, Luke; Shah, Deesha; Huang, Xian; Xu, Baoxing; Yu, Cunjiang; Huang, Yonggang; Rogers, John A

2014-01-01

259

Epidermal photonic devices for quantitative imaging of temperature and thermal transport characteristics of the skin  

NASA Astrophysics Data System (ADS)

Characterization of temperature and thermal transport properties of the skin can yield important information of relevance to both clinical medicine and basic research in skin physiology. Here we introduce an ultrathin, compliant skin-like, or ‘epidermal’, photonic device that combines colorimetric temperature indicators with wireless stretchable electronics for thermal measurements when softly laminated on the skin surface. The sensors exploit thermochromic liquid crystals patterned into large-scale, pixelated arrays on thin elastomeric substrates; the electronics provide means for controlled, local heating by radio frequency signals. Algorithms for extracting patterns of colour recorded from these devices with a digital camera and computational tools for relating the results to underlying thermal processes near the skin surface lend quantitative value to the resulting data. Application examples include non-invasive spatial mapping of skin temperature with milli-Kelvin precision (±50?mK) and sub-millimetre spatial resolution. Demonstrations in reactive hyperaemia assessments of blood flow and hydration analysis establish relevance to cardiovascular health and skin care, respectively.

Gao, Li; Zhang, Yihui; Malyarchuk, Viktor; Jia, Lin; Jang, Kyung-In; Chad Webb, R.; Fu, Haoran; Shi, Yan; Zhou, Guoyan; Shi, Luke; Shah, Deesha; Huang, Xian; Xu, Baoxing; Yu, Cunjiang; Huang, Yonggang; Rogers, John A.

2014-09-01

260

Experimental measurement-device-independent verification of quantum steering  

NASA Astrophysics Data System (ADS)

Bell non-locality between distant quantum systems—that is, joint correlations which violate a Bell inequality—can be verified without trusting the measurement devices used, nor those performing the measurements. This leads to unconditionally secure protocols for quantum information tasks such as cryptographic key distribution. However, complete verification of Bell non-locality requires high detection efficiencies, and is not robust to typical transmission losses over long distances. In contrast, quantum or Einstein–Podolsky–Rosen steering, a weaker form of quantum correlation, can be verified for arbitrarily low detection efficiencies and high losses. The cost is that current steering-verification protocols require complete trust in one of the measurement devices and its operator, allowing only one-sided secure key distribution. Here we present measurement-device-independent steering protocols that remove this need for trust, even when Bell non-locality is not present. We experimentally demonstrate this principle for singlet states and states that do not violate a Bell inequality.

Kocsis, Sacha; Hall, Michael J. W.; Bennet, Adam J.; Saunders, Dylan J.; Pryde, Geoff J.

2015-01-01

261

Experimental measurement-device-independent verification of quantum steering.  

PubMed

Bell non-locality between distant quantum systems-that is, joint correlations which violate a Bell inequality-can be verified without trusting the measurement devices used, nor those performing the measurements. This leads to unconditionally secure protocols for quantum information tasks such as cryptographic key distribution. However, complete verification of Bell non-locality requires high detection efficiencies, and is not robust to typical transmission losses over long distances. In contrast, quantum or Einstein-Podolsky-Rosen steering, a weaker form of quantum correlation, can be verified for arbitrarily low detection efficiencies and high losses. The cost is that current steering-verification protocols require complete trust in one of the measurement devices and its operator, allowing only one-sided secure key distribution. Here we present measurement-device-independent steering protocols that remove this need for trust, even when Bell non-locality is not present. We experimentally demonstrate this principle for singlet states and states that do not violate a Bell inequality. PMID:25565297

Kocsis, Sacha; Hall, Michael J W; Bennet, Adam J; Saunders, Dylan J; Pryde, Geoff J

2015-01-01

262

Integrated seal for high-temperature electrochemical device  

DOEpatents

The present invention provides electrochemical device structures having integrated seals, and methods of fabricating them. According to various embodiments the structures include a thin, supported electrolyte film with the electrolyte sealed to the support. The perimeter of the support is self-sealed during fabrication. The perimeter can then be independently sealed to a manifold or other device, e.g., via an external seal. According to various embodiments, the external seal does not contact the electrolyte, thereby eliminating the restrictions on the sealing method and materials imposed by sealing against the electrolyte.

Tucker, Michael C; Jacobson, Craig P

2013-07-16

263

High Accuracy Temperature Measurements Using RTDs with Current Loop Conditioning  

NASA Technical Reports Server (NTRS)

To measure temperatures with a greater degree of accuracy than is possible with thermocouples, RTDs (Resistive Temperature Detectors) are typically used. Calibration standards use specialized high precision RTD probes with accuracies approaching 0.001 F. These are extremely delicate devices, and far too costly to be used in test facility instrumentation. Less costly sensors which are designed for aeronautical wind tunnel testing are available and can be readily adapted to probes, rakes, and test rigs. With proper signal conditioning of the sensor, temperature accuracies of 0.1 F is obtainable. For reasons that will be explored in this paper, the Anderson current loop is the preferred method used for signal conditioning. This scheme has been used in NASA Lewis Research Center's 9 x 15 Low Speed Wind Tunnel, and is detailed.

Hill, Gerald M.

1997-01-01

264

INNOVATIVE INSTRUMENTATION AND ANALYSIS OF THE TEMPERATURE MEASUREMENT FOR HIGH TEMPERATURE GASIFICATION  

SciTech Connect

The systematic tests of the gasifier simulator were conducted in this reporting period. In the systematic test, two (2) factors were considered as the experimental parameters, including air injection rate and water injection rate. Each experimental factor had two (2) levels, respectively. A special water-feeding device was designed and installed to the gasifier simulator. Analysis of Variances (ANOVA) was applied to the results of the systematic tests. The ANOVA shows that the air injection rate did have the significant impact to the temperature measurement in the gasifier simulator. The ANOVA also shows that the water injection rate did not have the significant impact to the temperature measurements in the gasifier simulator. The ANOVA analysis also proves that the thermocouple assembly we proposed was immune to the moisture environment, the temperature measurement remained accurate in moisture environment. Within this reporting period, the vibration application for cleaning purpose was explored. Both ultrasonic and sub-sonic vibrations were considered. A feasibility test was conducted to prove that the thermocouple vibration did not have the significant impact to the temperature measurements in the gasifier simulator. This feasibility test was a 2{sup 2} factorial design. Two factors including temperature levels and motor speeds were set to two levels respectively. The sub-sonic vibration tests were applied to the thermocouple to remove the concrete cover layer (used to simulate the solid condensate in gasifiers) on the thermocouple tip. It was found that both frequency and amplitude had significant impacts on removal performance of the concrete cover layer.

Seong W. Lee

2004-04-01

265

Measurement-device-independent quantum key distribution over 200 km  

E-print Network

Measurement-device-independent quantum key distribution (MDIQKD) protocol is immune to all attacks on detection and guarantees the information-theoretical security even with imperfect single photon detectors. Recently, several proof-of-principle demonstrations of MDIQKD have been achieved. Those experiments, although novel, are implemented through limited distance with a key rate less than 0.1 bps. Here, by developing a 75 MHz clock rate fully-automatic and highly-stable system, and superconducting nanowire single photon detectors with detection efficiencies more than 40%, we extend the secure transmission distance of MDIQKD to 200 km and achieve a secure key rate of three orders of magnitude higher. These results pave the way towards a quantum network with measurement-device-independent security.

Yan-Lin Tang; Hua-Lei Yin; Si-Jing Chen; Yang Liu; Wei-Jun Zhang; Xiao Jiang; Lu Zhang; Jian Wang; Li-Xing You; Jian-Yu Guan; Dong-Xu Yang; Zhen Wang; Hao Liang; Zhen Zhang; Nan Zhou; Xiongfeng Ma; Teng-Yun Chen; Qiang Zhang; Jian-Wei Pan

2014-07-30

266

Measurement-device-independent quantum key distribution with quantum memories  

NASA Astrophysics Data System (ADS)

We generalize measurement-device-independent quantum key distribution [Lo, Curty, and Qi, Phys. Rev. Lett. 108, 130503 (2012), 10.1103/PhysRevLett.108.130503] to the scenario where the Bell-state measurement station contains also heralded quantum memories. We find analytical formulas, in terms of device imperfections, for all quantities entering in the secret key rates, i.e., the quantum bit error rate and the repeater rate. We assume either single-photon sources or weak coherent pulse sources plus decoy states. We show that it is possible to significantly outperform the original proposal, even in presence of decoherence of the quantum memory. Our protocol may represent the first natural step for implementing a two-segment quantum repeater.

Abruzzo, Silvestre; Kampermann, Hermann; Bruß, Dagmar

2014-01-01

267

Measurement-Device-Independent Quantum Key Distribution over 200 km  

NASA Astrophysics Data System (ADS)

Measurement-device-independent quantum key distribution (MDIQKD) protocol is immune to all attacks on detection and guarantees the information-theoretical security even with imperfect single-photon detectors. Recently, several proof-of-principle demonstrations of MDIQKD have been achieved. Those experiments, although novel, are implemented through limited distance with a key rate less than 0.1 bit /s . Here, by developing a 75 MHz clock rate fully automatic and highly stable system and superconducting nanowire single-photon detectors with detection efficiencies of more than 40%, we extend the secure transmission distance of MDIQKD to 200 km and achieve a secure key rate 3 orders of magnitude higher. These results pave the way towards a quantum network with measurement-device-independent security.

Tang, Yan-Lin; Yin, Hua-Lei; Chen, Si-Jing; Liu, Yang; Zhang, Wei-Jun; Jiang, Xiao; Zhang, Lu; Wang, Jian; You, Li-Xing; Guan, Jian-Yu; Yang, Dong-Xu; Wang, Zhen; Liang, Hao; Zhang, Zhen; Zhou, Nan; Ma, Xiongfeng; Chen, Teng-Yun; Zhang, Qiang; Pan, Jian-Wei

2014-11-01

268

Measurement-device-independent quantum key distribution over 200 km.  

PubMed

Measurement-device-independent quantum key distribution (MDIQKD) protocol is immune to all attacks on detection and guarantees the information-theoretical security even with imperfect single-photon detectors. Recently, several proof-of-principle demonstrations of MDIQKD have been achieved. Those experiments, although novel, are implemented through limited distance with a key rate less than 0.1??bit/s. Here, by developing a 75 MHz clock rate fully automatic and highly stable system and superconducting nanowire single-photon detectors with detection efficiencies of more than 40%, we extend the secure transmission distance of MDIQKD to 200 km and achieve a secure key rate 3 orders of magnitude higher. These results pave the way towards a quantum network with measurement-device-independent security. PMID:25415890

Tang, Yan-Lin; Yin, Hua-Lei; Chen, Si-Jing; Liu, Yang; Zhang, Wei-Jun; Jiang, Xiao; Zhang, Lu; Wang, Jian; You, Li-Xing; Guan, Jian-Yu; Yang, Dong-Xu; Wang, Zhen; Liang, Hao; Zhang, Zhen; Zhou, Nan; Ma, Xiongfeng; Chen, Teng-Yun; Zhang, Qiang; Pan, Jian-Wei

2014-11-01

269

Surface photovoltage measurements and finite element modeling of SAW devices.  

SciTech Connect

Over the course of a Summer 2011 internship with the MEMS department of Sandia National Laboratories, work was completed on two major projects. The first and main project of the summer involved taking surface photovoltage measurements for silicon samples, and using these measurements to determine surface recombination velocities and minority carrier diffusion lengths of the materials. The SPV method was used to fill gaps in the knowledge of material parameters that had not been determined successfully by other characterization methods. The second project involved creating a 2D finite element model of a surface acoustic wave device. A basic form of the model with the expected impedance response curve was completed, and the model is ready to be further developed for analysis of MEMS photonic resonator devices.

Donnelly, Christine

2012-03-01

270

In Situ and Satellite Measured Temperature Comparability  

NASA Technical Reports Server (NTRS)

Following the International Geophysical Year in the late 1950's, small meteorological rockets caught the interest of scientists as a potentially inexpensive method to obtain meteorological information (density, temperature, wind) above balloon-borne radiosonde altitudes. These small rocketsondes have served many important observational roles in terms of studies conducted of atmospheric structure and processes, enabling many new ideas about the atmosphere to emerge. Although no longer manufactured a small residual inventory of meteorological rocketsondes exist for specific research projects. The value of data from meteorological rocketsondes is without question but with their disappearance data from many different satellites are filling the need, some able to resolve high-altitude temperatures quite well. However, the rocketsonde vertical profile is more localized to the launch site whereas satellites move several kilometers per second. The objective of this presentation is to compare in situ temperature data with remotely measured/retrieved temperature data. There have been a number of U.S. conducted missions utilizing the passive falling sphere data that we use to verify the comparability of retrieved temperatures from these satellites. Missions, some as early as 1991, were conducted in polar, equatorial, and mid-latitude locations. An important aspect is that a single satellite profile compared to a falling sphere profile often does not agree while high density satellite measurements when averaged over an area near the rocketsonde data area seems to be in better agreement. Radiosonde temperature data are used in the analysis when appropriate

Schmidlin, F. J.; Goldberg, R. A.; Bedrick, Mary; Rose, R. Lynn

2011-01-01

271

40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2011-07-01

272

40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2014-07-01

273

40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2013-07-01

274

40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2010-07-01

275

40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2013-07-01

276

40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2012-07-01

277

40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2013-07-01

278

40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2014-07-01

279

40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2010-07-01

280

40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2010-07-01

281

40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2012-07-01

282

40 CFR 60.1815 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1815 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2011-07-01

283

40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2014 CFR

...2014-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2014-07-01

284

40 CFR 60.1325 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 60.1325 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2012-07-01

285

40 CFR 62.15270 - How do I monitor the temperature of flue gases at the inlet of my particulate matter control device?  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false How do I monitor the temperature of flue gases at the inlet of my particulate... § 62.15270 How do I monitor the temperature of flue gases at the inlet of my particulate...a device to continuously measure the temperature of the flue gas stream at the inlet...

2011-07-01

286

Note: Zeeman splitting measurements in a high-temperature plasma  

SciTech Connect

The Zeeman effect has been used for measurement of magnetic fields in low-temperature plasma, but the diagnostic technique is difficult to implement in a high-temperature plasma. This paper describes new instrumentation and methodology for simultaneous measurement of the entire Doppler-broadened left and right circularly polarized Zeeman spectra in high-temperature plasmas. Measurements are made using spectra emitted parallel to the magnetic field by carbon impurities in high-temperature plasma. The Doppler-broadened width is much larger than the magnitude of the Zeeman splitting, thus simultaneous recording of the two circularly polarized Zeeman line profiles is key to accurate measurement of the magnetic field in the ZaP Z-pinch plasma device. Spectral data are collected along multiple chords on both sides of the symmetry axis of the plasma. This enables determination of the location of the current axis of the Z-pinch and of lower-bound estimates of the local magnetic field at specific radial locations in the plasma.

Golingo, R. P.; Shumlak, U.; Den Hartog, D. J. [Aerospace and Energetics Research Program, University of Washington, Seattle, Washington 98195-2250 (United States)

2010-12-15

287

[Detonation temperature measurement of epoxypropane using instantaneous spectrum method].  

PubMed

After solving the problems of synchronization of the measuring system and the avoidance of false trigger signal, the instantaneous emission spectrum of epoxypropane with an exposure time of 2 micros and a resolution of 0.2 nm was acquired from a side window of a shock tube at the very moment when the epoxypropane transformed from deflagration to detonation. The measuring system consists of an advanced intensified charge-coupled-device spectroscopic detector, a digital delay generator DG535, an explosion shock tube and optical fibers. The DDT process was monitored by pressure transducers. After correcting the intensity of the spectrum obtained, the background curve of the heat radiation intensity of the detonation was given immediately. The detonation temperature of 2 416 K for epoxypropane was derived from fitting the curve with Planck blackbody formula by least squares principle. The detonation temperature of epoxypropane can provide an experimental datum for analyzing the microscopic mechanism of DDT process. PMID:18536396

Li, Ying; Li, Ping; Xiao, Hai-Bo; Hu, Dong; Yuan, Chang-Ying

2008-03-01

288

Global trends of measured surface air temperature  

NASA Technical Reports Server (NTRS)

The paper presents the results of surface air temperature measurements from available meteorological stations for the period of 1880-1985. It is shown that the network of meteorological stations is sufficient to yield reliable long-term, decadal, and interannual temperature changes for both the Northern Hemisphere and the Southern Hemisphere, despite the fact that most stations are located on the continents. The results indicate a global warming of about 0.5-0.7 C in the past century, with warming of similar magnitude in both hemispheres. A strong warming trend between 1965 and 1980 raised the global mean temperature in 1980 and 1981 to the highest level in the period of instrumental records. Selected graphs of the temperature change in each of the eight latitude zones are included.

Hansen, James; Lebedeff, Sergej

1987-01-01

289

Measurement of surface temperature in lung cancer.  

PubMed

We measured the surface temperature of the tumors in 27 patients with primary lung cancer, using a flexible bronchofiberscope and a thermometer made from chromel-constantan. The thermometer was inserted into the aspiration channel of the bronchofiberscope, and temperature was studied under bronchofiberscopic located in the central portion of the lung were higher than those of the carina of the trachea (P less than 0.01), truncus superior (P less than 0.01), or truncus inferior (P less than 0.05), and almost equal to those of the peripheral lung. Thus, lung cancer showed a significantly higher surface temperature. When 67Ga scintigraphy was performed in 22 patients with lung cancer, the temperature of the high-uptake group was higher than that of the low-uptake group. PMID:6274590

Ohgimi, T; Akiyama, S; Shimokata, K

1982-01-01

290

Magnetic Susceptibility Measurements at Ultra-low Temperatures  

NASA Astrophysics Data System (ADS)

We report the design and operation of a device for ac magnetic susceptibility measurements that can operate down to 1 mK. The device, a modification of the standard mutual inductance bridge, is designed with detailed consideration of the thermalization and optimization of each element. First, in order to reduce local heating, the primary coil is made with superconducting wire. Second, a low-temperature transformer which is thermally anchored to the mixing chamber of a dilution refrigerator, is used to match the output of the secondary coil to a high-sensitivity bridge detector. The careful thermal anchoring of the secondary coil and the matching transformer is required to reduce the overall noise temperature and maximize sensitivity. The sample is immersed in liquid 3He to minimize the Kapitza thermal resistance. The magnetic susceptibility of several magnetic compounds, such as the well-known spin gap compound NiCl2-4SC(NH2)2 and other powdered samples, have been successfully measured to temperatures well below 10 mK.

Yin, L.; Xia, J. S.; Sullivan, N. S.; Zapf, V. S.; Paduan-Filho, A.

2010-02-01

291

SiC device development for high temperature sensor applications  

NASA Technical Reports Server (NTRS)

Progress made in the processing and characterization of 3C-SiC for high temperature sensor applications is reviewed. Piezoresistance properties of silicon carbide and the temperature coefficient of resistivity of n-type beta-SiC are presented. In addition, photoelectrical etching and dopant selective etch-stops in SiC and high temperature Ohmic contacts for n-type beta-SiC sensors are discussed.

Shor, J. S.; Goldstein, David; Kurtz, A. D.; Osgood, R. M.

1992-01-01

292

Critical temperature measurement method of composite superconductors  

NASA Astrophysics Data System (ADS)

The critical temperature ( Tc) is one of the most important properties in applications of superconductors. There are a lot of test methods to measure Tc of superconductors and therefore the standardization of the measurement method of Tc is needed. For those demands the draft of Tc measurement method was prepared by various organizations and committees in Japan. The outline of the method was the resistance method using a 50% resistance criterion, which is applicable to both metallic and oxide composite superconductors in industrial uses. The draft was submitted to IEC/TC90 and certified as a new work item proposal.

Murase, S.; Itoh, K.; Wada, H.; Noto, K.; Kimura, Y.; Tanaka, Y.; Osamura, K.

2001-08-01

293

40 CFR 89.325 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Engine intake air temperature measurement. 89.325 Section 89...Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within...

2013-07-01

294

40 CFR 89.325 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2014 CFR

...2013-07-01 true Engine intake air temperature measurement. 89.325 Section 89...Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within...

2014-07-01

295

40 CFR 89.325 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Engine intake air temperature measurement. 89.325 Section 89...Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within...

2010-07-01

296

40 CFR 89.325 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 false Engine intake air temperature measurement. 89.325 Section 89...Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within...

2011-07-01

297

40 CFR 89.325 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 false Engine intake air temperature measurement. 89.325 Section 89...Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within...

2012-07-01

298

Temperature measurements of shocked silica aerogel foam.  

PubMed

We present recent results of equation-of-state (EOS) measurements of shocked silica (SiO_{2}) aerogel foam at the OMEGA laser facility. Silica aerogel is an important low-density pressure standard used in many high energy density experiments, including the novel technique of shock and release. Due to its many applications, it has been a heavily studied material and has a well-known Hugoniot curve. This work then complements the velocity and pressure measurements with additional temperature data providing the full EOS information within the warm dense matter regime for the temperature interval of 1-15 eV and shock velocities between 10 and 40 km/s corresponding to shock pressures of 0.3-2 Mbar. The experimental results were compared with hydrodynamic simulations and EOS models. We found that the measured temperature was systematically lower than suggested by theoretical calculations. Simulations provide a possible explanation that the emission measured by optical pyrometry comes from a radiative precursor rather than from the shock front, which could have important implications for such measurements. PMID:25314547

Falk, K; McCoy, C A; Fryer, C L; Greeff, C W; Hungerford, A L; Montgomery, D S; Schmidt, D W; Sheppard, D G; Williams, J R; Boehly, T R; Benage, J F

2014-09-01

299

Measuring Rocket Engine Temperatures with Hydrogen Raman Spectroscopy  

NASA Technical Reports Server (NTRS)

Optically accessible, high pressure, hot fire test articles are available at NASA Marshall for use in development of advanced rocket engine propellant injectors. Single laser-pulse ultraviolet (UV) Raman spectroscopy has been used in the past in these devices for analysis of high pressure H2- and CH4-fueled combustion, but relies on an independent pressure measurement in order to provide temperature information. A variation of UV Raman (High Resolution Hydrogen Raman Spectroscopy) is under development and will allow temperature measurement without the need for an independent pressure measurement, useful for flows where local pressure may not be accurately known. The technique involves the use of a spectrometer with good spectral resolution, requiring a small entrance slit for the spectrometer. The H2 Raman spectrum, when created by a narrow linewidth laser source and obtained from a good spectral resolution spectrograph, has a spectral shape related to temperature. By best-fit matching an experimental spectrum to theoretical spectra at various temperatures, a temperature measurement is obtained. The spectral model accounts for collisional narrowing, collisional broadening, Doppler broadening, and collisional line shifting of each Raman line making up the H2 Stokes vibrational Q-branch spectrum. At pressures from atmospheric up to those associated with advanced preburner components (5500 psia), collisional broadening though present does not cause significant overlap of the Raman lines, allowing high resolution H2 Raman to be used for temperature measurements in plumes and in high pressure test articles. Experimental demonstrations of the technique are performed for rich H2-air flames at atmospheric pressure and for high pressure, 300 K H2-He mixtures. Spectrometer imaging quality is identified as being critical for successful implementation of technique.

Wehrmeyer, Joseph A.; Osborne, Robin J.; Trinh, Huu P.; Turner, James (Technical Monitor)

2001-01-01

300

Methods of measurement for semiconductor materials, process control, and devices  

NASA Technical Reports Server (NTRS)

Activities directed toward the development of methods of measurement for semiconductor materials, process control, and devices are described. Topics investigated include: measurements of transistor delay time; application of the infrared response technique to the study of radiation-damaged, lithium-drifted silicon detectors; and identification of a condition that minimizes wire flexure and reduces the failure rate of wire bonds in transistors and integrated circuits under slow thermal cycling conditions. Supplementary data concerning staff, standards committee activities, technical services, and publications are included as appendixes.

Bullis, W. M. (editor)

1972-01-01

301

Adaptive Blood Glucose Monitoring and Insulin Measurement Devices for Visually Impaired Persons.  

ERIC Educational Resources Information Center

This article describes devices that people with visual impairments and diabetes can use to monitor blood glucose levels and measure insulin. A table lists devices, their manufacturers (including address and telephone number), and comments about the devices. (DB)

Petzinger, R. A.

1993-01-01

302

Correcting horsepower measurements to a standard temperature  

NASA Technical Reports Server (NTRS)

This report discusses the relation between the temperature of the air at the entrance to the carburetor and the power developed by the engine. Its scope is limited to a consideration of the range of temperatures likely to result from changes of season, locality, or altitude, since its primary aim is the finding of a satisfactory basis for correcting power measurements to a standard temperature. The tests upon which this report is based were made upon aviation engines in the Altitude Laboratory of the Bureau of Standards. From the results of over 1,600 tests it is concluded that if calculations be based on the assumption that the indicated horsepower of an engine varies inversely as the square root of the absolute temperature of the carburetor air the values obtained will check closely experimental measurements. The extent to which this relationship would be expected from theoretical considerations is discussed and some suggestions are given relative to the use of this relationship in correcting horsepower measurements. (author)

Sparrow, Stanwood W

1925-01-01

303

STP Temperature Measurement Lennard-Jones Program  

NSDL National Science Digital Library

The STP TemperatureMeasurementLJ program simulates the exchange energy between a demon and a system of particles interacting via the Lennard-Jones potential. The program shows the kinetic temperature of the system as a function of time, and the energy distribution of the demon. The purpose of this simulation is to understand why the demon acts as an ideal thermometer The default system is a one-dimensional ideal gas of N=64 particles in a box with linear dimension 30 and initial kinetic energy per particle of 1.0. Additional states and parameters can be specified using the Display|Switch GUI menu item. STP TemperatureMeasurementLJ is part of a suite of Open Source Physics programs that model aspects of Statistical and Thermal Physics (STP). The program is distributed as a ready-to-run (compiled) Java archive. Double-clicking the stp_TemperatureMeasurementLJ.jar file will run the program if Java is installed on your computer. Additional programs can be found by searching ComPADRE for Open Source Physics, STP, or Statistical and Thermal Physics.

Gould, Harvey; Tobochnik, Jan; Christian, Wolfgang; Cox, Anne

2009-03-03

304

Superconducting switch permits measurement of small voltages at cryogenic temperatures  

NASA Technical Reports Server (NTRS)

Dual-coil, superconducting, on-off switch measures small, thermoelectrically generated voltages produced by thermocouples in a liquid helium bath. Placed in a shunt configuration between the thermocouple and the measuring device, the measuring device sees the sum of the voltage to be measured and the spurious thermoelectric voltages.

Govednik, R. E.; Huebener, R. P.

1968-01-01

305

Wireless Temperature Measurement and Control System Based on MSP430F149  

Microsoft Academic Search

This design takes the 16-bit ultra-low power MSP430F149 micro controller produced by TI Company as the control core. Using a high-precision single-bus device DS18B20 as the temperature sensor, the keyboard as the temperature input setting, and the temperature value displayed by the 1602 LCD, temperature measurement and controlling are realized within the closed environment. And the nRF401 wireless transmission module

Wei Jia; Peng Xie; Guo-qin Feng

2010-01-01

306

Modeling and Evaluation of Canted Coil Springs as High Temperature Seal Preloading Devices  

NASA Technical Reports Server (NTRS)

Future reusable launch vehicles will require advanced structural seals. This includes propulsion seals along edges and hinge lines in hypersonic engines, and control surface seals for movable flaps and elevons on proposed reentry vehicles. Seals must remain in sealing engagement with opposing surfaces, for multiple missions, even though the seal gap may be opening and closing due to thermal and structural loads. To meet this requirement either the seals themselves must be resilient or there must be a resilient structural element behind the seals. Case Western Reserve University is working with NASA s Glenn Research Center to develop more resilient high temperature seal components and preloading devices. Results are presented for a finite element analysis of a canted coil spring that is being considered as a high temperature seal preloading device. This type of spring is a leading candidate due to its ability to provide nearly constant force over a large deflection. The finite element analyses were verified by comparing them to experimental results of canted coil springs of three different stiffnesses, measured at Glenn Research Center. Once validated the parameterized model was combined with a scripting algorithm to assess the effects of key spring design variables (wire diameter, coils per inch, cant amplitude, eccentricity, and spring width) on spring stiffness and maximum Von Mises stress to aid in subsequent design.

Oswald, Jay J.; Mullen, Robert L.; Dunlap, Patrick H., Jr.; Steinetz, Bruce M.

2004-01-01

307

Apparatus for gas sorption measurement with integrated gas composition measurement device and gas mixing  

SciTech Connect

An apparatus for testing of multiple material samples includes a gas delivery control system operatively connectable to the multiple material samples and configured to provide gas to the multiple material samples. Both a gas composition measurement device and pressure measurement devices are included in the apparatus. The apparatus includes multiple selectively openable and closable valves and a series of conduits configured to selectively connect the multiple material samples individually to the gas composition device and the pressure measurement devices by operation of the valves. A mixing system is selectively connectable to the series of conduits and is operable to cause forced mixing of the gas within the series of conduits to achieve a predetermined uniformity of gas composition within the series of conduits and passages.

Micklash. II, Kenneth James; Dutton, Justin James; Kaye, Steven

2014-06-03

308

AC loss in high-temperature superconducting conductors, cables and windings for power devices  

Microsoft Academic Search

High-temperature superconducting (HTS) transformers and reactor coils promise decreased weight and volume and higher efficiency. A critical design parameter for such devices is the AC loss in the conductor. The state of the art for AC-loss reduction in HTS power devices is described, starting from the loss in the single HTS tape. Improved tape manufacturing techniques have led to a

M. P. Oomen; J. Rieger; V. Hussennether; M. Leghissa

2004-01-01

309

76 FR 81363 - Temperature-Indicating Devices; Thermally Processed Low-Acid Foods Packaged in Hermetically...  

Federal Register 2010, 2011, 2012, 2013, 2014

...foods packaged in hermetically sealed containers to allow for use of other temperature-indicating devices, in addition to mercury-in-glass thermometers, during processing. The final rule was published with one error. This document corrects that...

2011-12-28

310

Flow and Temperature Fields Generated by a Thermally Activated Interventional Vascular Device  

E-print Network

Concern for the nonphysiologic energy required to actuate medical devices utilizing “smart material” properties of shape memory polymer (SMP) compels a rigorous investigation into the flow and temperature fields surrounding a thermally activated...

McCurrin, Casey

2012-10-19

311

EVALUATING AND TESTING EMERGENCY TESTING MONITORING DEVICES IN EXTREME COLD TEMPERATURES  

EPA Science Inventory

EPA Identifier: F8P11070 Title: Evaluating and Testing Emergency Testing Monitoring Devices in Extreme Cold Temperatures Fellow (Principal Investigator): Tyler S. O?Dell Institution: Lake Superior State University EPA GRANT Represent...

312

Improved Refractometer for Measuring Temperatures of Drops  

NASA Technical Reports Server (NTRS)

The Dual Rainbow refractometer is an enhanced version of the Rainbow refractometer, which is added to, and extends the capabilities of, a phase Doppler particle analyzer (PDPA). A PDPA utilizes pairs of laser beams to measure individual components of velocity and sizes of drops in a spray. The Rainbow-refractometer addition measures the temperatures of individual drops. The designs of prior versions of the Rainbow refractometer have required substantial modifications of PDPA transmitting optics, plus dedicated lasers as sources of illumination separate from, and in addition to, those needed for PDPA measurements. The enhancement embodied in the Dual Rainbow refractometer eliminates the need for a dedicated laser and confers other advantages as described below. A dedicated laser is no longer needed because the Dual Rainbow refractometer utilizes one of the pairs of laser beams already present in a PDPA. Hence, the design of the Dual Rainbow refractometer simplifies the task of upgrading PDPA hardware to enable measurement of temperature. Furthermore, in a PDPA/Dual Rainbow refractometer system, a single argon-ion laser with three main wavelengths can be used to measure the temperatures, sizes, and all three components of velocity (in contradistinction to only two components of velocity in a prior PDPA/Rainbow refractometer system). In order to enable the Dual Rainbow refractometer to utilize a pair of PDPA laser beams, it was necessary to (1) find a location for the refractometer receiver, such that the combined rainbow patterns of two laser beams amount to a pattern identical to that of a single beam, (2) adjust the polarization of the two beams to obtain the strongest rainbow pattern, and (3) find a location for the PDPA receiver to obtain a linear relationship between the measured phase shift and drop size.

Naqwi, Amir A.

2004-01-01

313

High-temperature superconducting thin-film-based electronic devices  

SciTech Connect

This the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project involved optimization of processing of Y123 and Tl-2212 thin films deposited on novel substrates for advanced electronic devices. The Y123 films are the basis for development of Josephson Junctions to be utilized in magnetic sensors. Microwave cavities based on the Tl-2212 films are the basis for subsequent applications as communication antennas and transmitters in satellites.

Wu, X.D; Finokoglu, A.; Hawley, M.; Jia, Q.; Mitchell, T.; Mueller, F.; Reagor, D.; Tesmer, J.

1996-09-01

314

A study of the combined influence of temperature and material defects on semiconductor device performance  

E-print Network

as to style and content by: (Chairman of Committee) (Head +of Depart nt) zP~ ember) (Member) May 1976 ABSTRACT A Study of the Combined Influence of Temperature and Material Defects on Semiconductor Device Performance. (May 1976) Kanaiyalal C. Patel, B...A STUDY OF THE COMBINED INFLUENCE OF TEMPERATURE AND MATERIAL DEFECTS ON SEMICONDUCTOR DEVICE PERFORMANCE A Thesis by KANAIYALAL CHATURBEAI PATEL Submitted to the Graduate College of Texas A&M University in Partial fulfillment...

Patel, Kanaiyalal Chaturbhai

1976-01-01

315

The effects of substrate temperature on ZnO-based resistive random access memory devices  

Microsoft Academic Search

Ag\\/ZnO\\/Zn\\/Pt structure resistive switching devices are prepared by radio frequency magnetron sputtering. The ZnO thin films are grown at room temperature and 400°C substrate temperature, respectively. By comparing the data, we find that the latter device displayed better stability in the repetitive switching cycle test, and the resistance ratio between a high resistance state and a low resistance state is

Zhao Jian-Wei; Liu Feng-Juan; Huang Hai-Qin; Hu Zuo-Fu; Zhang Xi-Qing

2012-01-01

316

Thermoreflectance temperature measurement with millimeter wave  

NASA Astrophysics Data System (ADS)

GigaHertz (GHz) thermoreflectance technique is developed to measure the transient temperature of metal and semiconductor materials located behind an opaque surface. The principle is based on the synchronous detection, using a commercial THz pyrometer, of a modulated millimeter wave (at 110 GHz) reflected by the sample hidden behind a shield layer. Measurements were performed on aluminum, copper, and silicon bulks hidden by a 5 cm thick Teflon plate. We report the first measurement of the thermoreflectance coefficient which exhibits a value 100 times higher at 2.8 mm radiation than those measured at visible wavelengths for both metallic and semiconductor materials. This giant thermoreflectance coefficient ?, close to 10-3 K-1 versus 10-5 K-1 for the visible domain, is very promising for future thermoreflectance applications.

Pradere, C.; Caumes, J.-P.; BenKhemis, S.; Pernot, G.; Palomo, E.; Dilhaire, S.; Batsale, J.-C.

2014-06-01

317

Thermoreflectance temperature measurement with millimeter wave.  

PubMed

GigaHertz (GHz) thermoreflectance technique is developed to measure the transient temperature of metal and semiconductor materials located behind an opaque surface. The principle is based on the synchronous detection, using a commercial THz pyrometer, of a modulated millimeter wave (at 110 GHz) reflected by the sample hidden behind a shield layer. Measurements were performed on aluminum, copper, and silicon bulks hidden by a 5 cm thick Teflon plate. We report the first measurement of the thermoreflectance coefficient which exhibits a value 100 times higher at 2.8 mm radiation than those measured at visible wavelengths for both metallic and semiconductor materials. This giant thermoreflectance coefficient ?, close to 10(-3) K(-1) versus 10(-5) K(-1) for the visible domain, is very promising for future thermoreflectance applications. PMID:24985839

Pradere, C; Caumes, J-P; BenKhemis, S; Pernot, G; Palomo, E; Dilhaire, S; Batsale, J-C

2014-06-01

318

Measurement of small differences between low temperatures  

Microsoft Academic Search

1.A manganin-constantan thermocouple was prepared.2.Calibration of the thermocouple between 273 and 73°K showed that its electromotive force is close to that of a copper-constantan thermocouple, whereas its heat conductivity lies between 1 and 10% relative to the latter.3.The manganin-constantan thermocouple may be recommended for measuring small differences between low temperatures in adiabatic microcalorimeters.

M. G. Ostronov; Yu. B. Samarin; V. N. Koloshina

1972-01-01

319

A Fast Microfluidic Temperature Control Device for Studying Microtubule Dynamics in Fission Yeast  

PubMed Central

Recent development in soft lithography and microfluidics enables biologists to create tools to control the cellular microenvironment. One such control is the ability to quickly change the temperature of the cells. Genetic model organism such as fission yeast has been useful for studies of the cell cytoskeleton. In particular, the dynamic microtubule cytoskeleton responds to changes in temperature. In addition, there are temperature-sensitive mutations of cytoskeletal proteins. We describe here the fabrication and use of a microfluidic device to quickly and reversibly change cellular temperature between 2°C and 50°C. We demonstrate the use of this device while imaging at high-resolution microtubule dynamics in fission yeast. PMID:20719272

Velve-Casquillas, Guilhem; Costa, Judite; Carlier-Grynkorn, Frédérique; Mayeux, Adeline; Tran, Phong T.

2010-01-01

320

Temperature-dependent single carrier device model for polymeric light emitting diodes  

NASA Astrophysics Data System (ADS)

We present an investigation of the temperature dependence of the current-voltage characteristics of a single carrier poly[2-methoxy, 5-(2´-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) polymer light-emitting diode (LED) with indium tin oxide (ITO) and aluminium electrodes. We find that although injection effects are the dominant current limiting mechanisms, bulk transport effects also play a significant role due to the low charge carrier mobility. Tunnelling theory cannot account for the observations made and we find that the tunnelling barrier predicted by a simple Fowler-Nordheim analysis increases by more than a factor of two from 0.2 to 0.45 eV as the LED is cooled from room temperature to 13 K. We use a device model combining the interfacial currents of thermionic emission, tunnelling and interface recombination, with drift currents to describe successfully the measured current-voltage characteristics over a temperature range from 300 K to 100 K using the barrier height to injection and the field-dependent mobility as fitting parameters. Good quality fits are obtained over a wide range of temperatures. The field-dependent mobility parameters are found to have a temperature dependence characteristic of hopping in disordered solids with an activation energy of 0.75 eV for the zero field mobility. The barrier to injection for holes from the ITO anode is found to be lowered from 0.56 eV at 300 K to 0.41 eV at 100 K, which can in part be accounted for by the reduction of the band gap of MEH-PPV with decreasing temperature. The temperature dependence of the parameters is greater than values reported elsewhere, suggesting that approximating the thermally-activated, microscopic injection processes by a thermionic emission term overestimates the activation energy for charge carrier injection. We looked at the effect of photo-oxidation on device characteristics as a further test of the model and found that these modified characteristics are well described by a substantial reduction in mobility at constant barrier height.

Lupton, J. M.; Samuel, I. D. W.

1999-12-01

321

PARduino: A Simple Device Measuring and Logging Photosynthetically Active Radiation  

NASA Astrophysics Data System (ADS)

Photosynthetically Active Radiation (PAR, 400 to 700 nm) is one of the primary controls of forest carbon and water relations. In complex terrain, PAR has high spatial-variability. Given the high cost of commercial datalogging equipment, spatially-distributed measurements of PAR have been typically modeled using geographic coordinates and terrain indices. Here, we present a design for a low cost, field-deployable device for measuring and logging PAR built around an Arduino microcontroller (we named it PARduino). PARduino provides for widely distributed sensor arrays and tests the feasibility of using hobbyist-grade electronics for collecting scientific data. PARduino components include a LiCor quantum sensor, EME Systems signal converter/amplifier, and Sparkfun's Arduino Pro Mini microcontroller. Additional components include a real time clock, a microSD flash memory card, and a custom printed circuit board (PCB). We selected the components with an eye towards ease of assembly. Everything can be connected to the PCB using through-hole soldering techniques. Since the device will be deployed in remote research plots that lack easy access to line power, battery life was also a consideration in the design. Extended deployment is possible because PARduino's software keeps it in a low-power sleep mode until ready to make a measurement. PARduino will be open-source hardware for use and improvement by others.

Barnard, H. R.; Findley, M. C.

2013-12-01

322

New simulation and measurement results on gateable DEPFET devices  

NASA Astrophysics Data System (ADS)

To improve the signal to noise level, devices for optical and x-ray astronomy use techniques to suppress background events. Well known examples are e.g. shutters or frame-store Charge Coupled Devices (CCDs). Based on the DEpleted P-channel Field Effect Transistor (DEPFET) principle a so-called Gatebale DEPFET detector can be built. Those devices combine the DEPFET principle with a fast built-in electronic shutter usable for optical and x-ray applications. The DEPFET itself is the basic cell of an active pixel sensor build on a fully depleted bulk. It combines internal amplification, readout on demand, analog storage of the signal charge and a low readout noise with full sensitivity over the whole bulk thickness. A Gatebale DEPFET has all these benefits and obviates the need for an external shutter. Two concepts of Gatebale DEPFET layouts providing a built-in shutter will be introduced. Furthermore proof of principle measurements for both concepts are presented. Using recently produced prototypes a shielding of the collection anode up to 1 • 10-4 was achieved. Predicted by simulations, an optimized geometry should result in values of 1 • 10-5 and better. With the switching electronic currently in use a timing evaluation of the shutter opening and closing resulted in rise and fall times of 100ns.

Bähr, Alexander; Aschauer, Stefan; Hermenau, Katrin; Herrmann, Sven; Lechner, Peter H.; Lutz, Gerhard; Majewski, Petra; Miessner, Danilo; Porro, Matteo; Richter, Rainer H.; Schaller, Gerhard; Sandow, Christian; Schnecke, Martina; Schopper, Florian; Stefanescu, Alexander; Strüder, Lothar; Treis, Johannes

2012-07-01

323

Density measurements Viscosity measurements  

E-print Network

Density measurements Viscosity measurements Temperature measurements Pressure measurements Flow Ravelet Experimental methods for fluid flows: an introduction #12;Density measurements Viscosity viscosity temperature pressure flow rate velocity Sensor definition: it is a device which changes a physical

Ravelet, Florent

324

Methods of measurement for semiconductor materials, process control, and devices  

NASA Technical Reports Server (NTRS)

The development of methods of measurement for semiconductor materials, process control, and devices is discussed. The following subjects are also presented: (1) demonstration of the high sensitivity of the infrared response technique by the identification of gold in a germanium diode, (2) verification that transient thermal response is significantly more sensitive to the presence of voids in die attachment than steady-state thermal resistance, and (3) development of equipment for determining susceptibility of transistors to hot spot formation by the current-gain technique.

Bullis, W. M. (editor)

1971-01-01

325

Description of a Portable Wireless Device for High-Frequency Body Temperature Acquisition and Analysis  

PubMed Central

We describe a device for dual channel body temperature monitoring. The device can operate as a real time monitor or as a data logger, and has Bluetooth capabilities to enable for wireless data download to the computer used for data analysis. The proposed device is capable of sampling temperature at a rate of 1 sample per minute with a resolution of 0.01 °C . The internal memory allows for stand-alone data logging of up to 10 days. The device has a battery life of 50 hours in continuous real-time mode. In addition to describing the proposed device in detail, we report the results of a statistical analysis conducted to assess its accuracy and reproducibility. PMID:22408473

Cuesta-Frau, David; Varela, Manuel; Aboy, Mateo; Miró-Martínez, Pau

2009-01-01

326

7 CFR 28.301 - Measurement: humidity; temperature.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Measurement: humidity; temperature. 28.301 Section 28.301 Agriculture...28.301 Measurement: humidity; temperature. The length of staple of any...of the atmosphere of 65 percent and a temperature of 70...

2012-01-01

327

7 CFR 28.301 - Measurement: humidity; temperature.  

Code of Federal Regulations, 2014 CFR

...2014-01-01 false Measurement: humidity; temperature. 28.301 Section 28.301 Agriculture...28.301 Measurement: humidity; temperature. The length of staple of any...of the atmosphere of 65 percent and a temperature of 70...

2014-01-01

328

7 CFR 28.301 - Measurement: humidity; temperature.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Measurement: humidity; temperature. 28.301 Section 28.301 Agriculture...28.301 Measurement: humidity; temperature. The length of staple of any...of the atmosphere of 65 percent and a temperature of 70...

2013-01-01

329

7 CFR 28.301 - Measurement: humidity; temperature.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Measurement: humidity; temperature. 28.301 Section 28.301 Agriculture...28.301 Measurement: humidity; temperature. The length of staple of any...of the atmosphere of 65 percent and a temperature of 70...

2011-01-01

330

7 CFR 28.301 - Measurement: humidity; temperature.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Measurement: humidity; temperature. 28.301 Section 28.301 Agriculture...28.301 Measurement: humidity; temperature. The length of staple of any...of the atmosphere of 65 percent and a temperature of 70°...

2010-01-01

331

Magnetic resonance flow velocity and temperature mapping of a shape memory polymer foam device  

PubMed Central

Background Interventional medical devices based on thermally responsive shape memory polymer (SMP) are under development to treat stroke victims. The goals of these catheter-delivered devices include re-establishing blood flow in occluded arteries and preventing aneurysm rupture. Because these devices alter the hemodynamics and dissipate thermal energy during the therapeutic procedure, a first step in the device development process is to investigate fluid velocity and temperature changes following device deployment. Methods A laser-heated SMP foam device was deployed in a simplified in vitro vascular model. Magnetic resonance imaging (MRI) techniques were used to assess the fluid dynamics and thermal changes associated with device deployment. Results Spatial maps of the steady-state fluid velocity and temperature change inside and outside the laser-heated SMP foam device were acquired. Conclusions Though non-physiological conditions were used in this initial study, the utility of MRI in the development of a thermally-activated SMP foam device has been demonstrated. PMID:20043833

2009-01-01

332

The display of portable infrared measuring temperature  

NASA Astrophysics Data System (ADS)

In recent years based on security, quality supervision, inspection and medical for the urgent need of infrared temperature measurement and infrared display technology, coupled with embedded system to achieve rapid development, which is widely used in the electronic products and the field of intelligent instruments and industrial control, this paper has designed a kind of more comprehensive, more efficient and more intuitive infrared thermometer. Unlike previous handheld infrared thermometer, we regard an embedded Linux system as the system, with its open source code, support most mainstream hardware platforms, unified peripheral interface and can be customized, to build an embedded infrared system that has provided strong system support; the pseudocolor techniques and Qt interface display technology make the image more colorful and the picture function more diverse; With ARM microprocessor as the display and temperature measuring platform, it costs reduction and reduce volume and power consumption; the FrameBuffer interface technology and multithreading technology realize the smooth real-time display. And ultimately the display size of real-time infrared image is 640 * 480 at a speed of 25 frames / sec. What is more, display is equipped with the menu option so that thermometer can be required to complete the operation through the button. The temperature display system aims at small volume, easy to use and flexible. I believe this thermometer will have a good application prospect.

Qian, Yitao; Gu, Guohua; Sui, Xiubao

2014-11-01

333

77 FR 17457 - Work Group on Alternative Test Methods for Commercial Measuring Devices  

Federal Register 2010, 2011, 2012, 2013, 2014

...to be discussed by the WG for current and proposed device technologies used in testing commercial measuring devices are: metrology laboratory standards and test procedures; uncertainties; measurement traceability; tolerances and other technical...

2012-03-26

334

Modeling of SiC Lateral Resonant Devices Over a Broad Temperature Range  

NASA Technical Reports Server (NTRS)

Finite-element analysis (FEA) modal results of 3C-SiC lateral resonant devices anchored to a Si substrate are presented as resonant frequency versus temperature. The suspended elements are etched from a 2 micron, 3C-SiC film grown at 1600 K on a 500 micron-thick, Si substrate. The analysis includes, temperature-dependent properties, shape change due to volume expansion with temperature, and thermal stress caused by differential thermal expansion of different materials. Two designs are considered: type I has anchor locations close to the geometric centroid and a small shuttle; type 11 has a large shuttle with anchors far from the centroid, The resonant frequency decreases approximately 3.5% over a 1000 K temperature increase for the type-I device, and behaves according to theory. The resonant frequency of the type-11 device decreases by 2% over the first 400 K, then rises slightly over the remaining 600 K. This device deviates from theory because of the high thermal stress induced in the beams. The thermal stress is caused by the differential thermal expansion of the suspended element relative to the substrate. The results show that the device geometry must be properly chosen if the resonant frequency of that device will be used to calculate the temperature coefficient of Young's modulus. These results apply only to resonators of one material on a substrate of a different material.

DeAnna, Russell G.; Roy, Shuvo; Zorman, Christian A.; Mehregany, Mehran

1999-01-01

335

Temperature measurements during laser skin welding  

NASA Astrophysics Data System (ADS)

A thermal camera was used to measure surface temperatures during laser skin welding to provide feedback for optimization of the laser parameters. Two-cm-long, full- thickness incisions were made in guinea pig skin. India ink was used as an absorber. Continuous-wave, 1.06-?m, Nd:YAG laser radiation was scanned over the incisions, producing a pulse duration of approximately 100 ms. Cooling durations between scans of 1.6, 4.0, and 8.0 s were studied with total operation times of 3, 5, and 10 min, respectively. A laser spot diameter of 5 mm was used with the power constant at 10 W. Thermal images were obtained at 30 frames per second with a thermal camera detecting 3.5 micrometers radiation. Surface temperatures were recorded at 0, 1, and 6 mm from the center line of the incision. Cooling durations between scans of 1.6 s and 4.0 s in vitro resulted in temperatures at the weld site remaining above ~65°C for prolonged periods of time. Cooling durations between scans as long as 8.0 s were sufficient both in vitro and in vivo to prevent a significant rise in baseline temperatures at the weld site over time.

Fried, Nathaniel M.; Choi, Bernard; Welch, Ashley J.; Walsh, Joseph T., Jr.

1999-06-01

336

Design of a Device for Sky Light Polarization Measurements  

PubMed Central

Sky polarization patterns can be used both as indicators of atmospheric turbidity and as a sun compass for navigation. The objective of this study is to improve the precision of sky light polarization measurements by optimal design of the device used. The central part of the system is composed of a Charge Coupled Device (CCD) camera; a fish-eye lens and a linear polarizer. Algorithms for estimating parameters of the polarized light based on three images are derived and the optimal alignments of the polarizer are analyzed. The least-squares estimation is introduced for sky light polarization pattern measurement. The polarization patterns of sky light are obtained using the designed system and they follow almost the same patterns of the single-scattering Rayleigh model. Deviations of polarization angles between observation and the theory are analyzed. The largest deviations occur near the sun and anti-sun directions. Ninety percent of the deviations are less than 5° and 40% percent of them are less than 1°. The deviations decrease evidently as the degree of polarization increases. It also shows that the polarization pattern of the cloudy sky is almost identical as in the blue sky. PMID:25196003

Wang, Yujie; Hu, Xiaoping; Lian, Junxiang; Zhang, Lilian; Xian, Zhiwen; Ma, Tao

2014-01-01

337

Multilayer compressive seal for sealing in high temperature devices  

DOEpatents

A mica based compressive seal has been developed exhibiting superior thermal cycle stability when compared to other compressive seals known in the art. The seal is composed of compliant glass or metal interlayers and a sealing (gasket) member layer composed of mica that is infiltrated with a glass forming material, which effectively reduces leaks within the seal. The compressive seal shows approximately a 100-fold reduction in leak rates compared with previously developed hybrid seals after from 10 to about 40 thermal cycles under a compressive stress of from 50 psi to 100 psi at temperatures in the range from 600.degree. C. to about 850.degree. C.

Chou, Yeong-Shyung (Richland, WA); Stevenson, Jeffry W. (Richland, WA)

2007-08-21

338

Skin friction measurements in high temperature high speed flows  

NASA Technical Reports Server (NTRS)

An experimental investigation was conducted to measure skin friction along the chamber walls of supersonic combustors. A direct force measurement device was used to simultaneously measure an axial and transverse component of the small tangential shear force passing over a non-intrusive floating element. The floating head is mounted to a stiff cantilever beam arrangement with deflection due to the flow on the order of 0.00254 mm (0.0001 in.). This allowed the instrument to be a non-nulling type. A second gauge was designed with active cooling of the floating sensor head to eliminate non-uniform temperature effects between the sensor head and the surrounding wall. Samples of measurements made in combustor test facilities at NASA Langley Research Center and at the General Applied Science Laboratory (GASL) are presented. Skin friction coefficients between 0.001 - 0.005 were measured dependent on the facility and measurement location. Analysis of the measurement uncertainties indicate an accuracy to within +/- 10-15 percent of the streamwise component.

Schetz, J. A.; Diller, Thomas E.; Wicks, A. L.

1992-01-01

339

High sensitivity optical fiber temperature sensor based on the temperature cross-sensitivity feature of RI-sensitive device  

NASA Astrophysics Data System (ADS)

Considerable part of optical fiber refractive index (RI) sensors suffer from the drawback of cross-sensitivity to temperature because of the thermo-optic effect of materials. In this paper, we propose a straightforward method to utilize the temperature cross-sensitivity feature of an optical fiber RI-sensitive device and thus got a high sensitivity temperature sensor. The sensor consists of a single mode fiber-multimode fiber core(MMFC)-single mode fiber structural refractometer encapsulated into a deionized water-filled cylindrical aluminum alloy shell. Benefiting from the larger thermo-optic coefficient difference between water and MMFC compared with the general cladding and core, the wavelength of transmitted spectrum presents enhanced shift when the ambient temperature change and thus get a higher temperature sensitivity. Experimental results show that the enhanced temperature sensitivity is about 358 pm/°C, which is almost 30 times that of the inherent temperature sensitivity.

Sun, Hao; Hu, Manli; Rong, Qiangzhou; Du, Yanying; Yang, Hangzhou; Qiao, Xueguang

2014-07-01

340

77 FR 35745 - Highway Safety Programs; Conforming Products List of Screening Devices To Measure Alcohol in...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Products List of Screening Devices To Measure Alcohol in Bodily Fluids AGENCY: National Highway...Specifications for Screening Devices to Measure Alcohol in Bodily Fluids dated, March 31, 2008...Specifications for Screening Devices to Measure Alcohol in Bodily Fluids (59 FR 39382)....

2012-06-14

341

Instrument for Measuring Temperature of Water  

NASA Technical Reports Server (NTRS)

A pseudo-Brewster angle infrared radiometer has been proposed for use in noncontact measurement of the surface temperature of a large body of water (e.g., a lake or ocean). This radiometer could be situated on a waterborne, airborne, or spaceborne platform. The design of the pseudo-Brewster angle radiometer would exploit the spectral emissivity and polarization characteristics of water to minimize errors attributable to the emissivity of water and to the reflection of downwelling (e.g., Solar and cloud-reflected) infrared radiation.

Ryan, Robert; Nixon, Thomas; Pagnutti, Mary; Zanoni, Vicki

2002-01-01

342

A new high-temperature indentation device for characterization of materials for fusion applications  

NASA Astrophysics Data System (ADS)

For material characterization tests that simulate the operating conditions in a fusion reactor, high-temperature experiments on irradiated samples are necessary. After successful indentation investigations at room temperature, the next step is an adaption of the experiment to elevated temperatures. A high-temperature indentation device designed for this application was constructed and realized at the Karlsruhe Institute of Technology (KIT). This device will be installed in a hot cell of the Fusion Materials Laboratory, Institute for Applied Materials. A description of chosen solutions and construction details for realization of the device are given: the properties as well as the main parts of the new apparatus—sample heating and positioning, vacuum system, force actuator, and remote handling solutions—are described.

Albinski, B.; Schneider, H.-C.; Sacksteder, I.; Kraft, O.

2013-11-01

343

Stage for texture measurements above room temperature in a Philips X'Pert Pro MPD diffractometer  

NASA Astrophysics Data System (ADS)

A special stage for texture measurements above room temperature was designed with the proper size and weight to be fitted onto the Eulerean cradle of the Philips X'Pert Pro MPD diffractometer. With such device, flat samples of 2×2 cm2 area can be analyzed at a nearly constant temperature with variations below ±4 °C in the range between ambient temperature and 200 °C.

Sobrero, César E.; Castellani, Daniel; Bolmaro, Raúl E.; Malarría, Jorge A.

2009-11-01

344

Characterization of devices, circuits, and high-temperature superconductor transmission lines by electro-optic testing  

NASA Technical Reports Server (NTRS)

The development of a capability for testing transmission lines, devices, and circuits using the optically-based technique of electro-optics sampling was the goal of this project. Electro-optic network analysis of a high-speed device was demonstrated. The project involved research on all of the facets necessary in order to realize this result, including the discovery of the optimum electronic pulse source, development of an adequate test fixture, improvement of the electro-optic probe tip, and identification of a device which responded at high frequency but did not oscillate in the test fixture. In addition, during the process of investigating patterned high-critical-temperature superconductors, several non-contacting techniques for the determination of the transport properties of high T(sub c) films were developed and implemented. These are a transient, optical pump-probe, time-resolved reflectivity experiment, an impulsive-stimulated Raman scattering experiment, and a terahertz-beam coherent-spectroscopy experiment. The latter technique has enabled us to measure both the complex refractive index of an MgO substrate used for high-T(sub c) films and the complex conductivity of a YBa2Cu3O(7-x) sample. This information was acquired across an extremely wide frequency range: from the microwave to the submillimeter-wave regime. The experiments on the YBCO were conducted without patterning of, or contact to, the thin film. Thus, the need for the more difficult transmission-line experiments was eliminated. Progress in all of these areas was made and is documented in a number of papers. These papers may be found in the section listing the abstracts of the publications that were issued during the course of the research.

Whitaker, John F.

1991-01-01

345

A device for measuring sonic velocity and compressor Mach number  

NASA Technical Reports Server (NTRS)

A device has been developed which measures the velocity of sound in fluids at stagnation and is especially adaptable to turbine and compressor testing for which the constituency of the working fluid may be in doubt. By utilizing the shaft frequency of a rotary compressor, the instrument can also be used to provide a direct measurement of the compressor Mach number (ratio of blade-tip velocity to inlet velocity of sound at stagnation). A Helmholtz resonator is employed in the measurement of the sound velocity. Viscous effects in the orifice of the Helmholtz resonator are shown to be important and can be taken into account with the help of a parameter obtained from Stokes solution of the flow near an oscillating wall. This parameter includes the kinematic viscosity of the fluid and the frequency of sound in the resonator. When these effects are recognized, the resonator can be calibrated to measure velocity of sound or compressor Mach number to an accuracy of better than 0.5 percent.

Huber, Paul W; Kantrowitz, Arthur

1947-01-01

346

A diffusive sampling device for measurement of ammonia in air  

NASA Astrophysics Data System (ADS)

A diffusive sampling device, the DSD-NH3, has been developed for measurement of ammonia in air. The DSD-NH3 comprises silica gel impregnated with phosphoric acid as the absorbent, a porous sintered polyethylene tube that acts as a diffusive membrane, and a small polypropylene syringe that is used for the elution of analytes from the absorbent. Silica gel impregnated with phosphoric acid is used as absorbent for the DSD-NH3; basic gases in ambient air, including ammonia, are trapped in the DSD-NH3 device by their reaction with phosphoric acid in the sampler to form their corresponding phosphoric acid salts. After collection, the DSD-NH3 samplers are eluted by water. Cations in the eluate, including ammonium ions, are analyzed by ion chromatography. A side-by-side comparison was made with active samplers, demonstrating good correlation (r2 = 0.996). The sampling rate (94.5 ml min-1) was determined from comparison with an active sampling method and sampling rates. The sampling rate is also calculated from the respective molecular weights according to a rule based on Graham's law. The theoretical sampling rate with the DSD-NH3 is 95.4 ml min-1 and agrees with the experimental value (94.5 ml min-1). Little influence of wind velocity on the sampler was observed. The relative standard deviations for ammonia concentrations were 4.7% with face velocity ranging 0-5.0 m/s.

Yamada, Tomomi; Uchiyama, Shigehisa; Inaba, Yohei; Kunugita, Naoki; Nakagome, Hideki; Seto, Hiroshi

2012-07-01

347

Device for accurately measuring mass flow of gases  

DOEpatents

A device for measuring mass flow of gases which utilizes a substantially buoyant pressure vessel suspended within a fluid/liquid in an enclosure is disclosed. The pressure vessel is connected to a weighing device for continuously determining weight change of the vessel as a function of the amount of gas within the pressure vessel. In the preferred embodiment, this pressure vessel is formed from inner and outer right circular cylindrical hulls, with a volume between the hulls being vented to the atmosphere external the enclosure. The fluid/liquid, normally in the form of water typically with an added detergent, is contained within an enclosure with the fluid/liquid being at a level such that the pressure vessel is suspended beneath this level but above a bottom of the enclosure. The buoyant pressure vessel can be interconnected with selected valves to an auxiliary pressure vessel so that initial flow can be established to or from the auxiliary pressure vessel prior to flow to or from the buoyant pressure vessel. 5 figs.

Hylton, J.O.; Remenyik, C.J.

1994-08-09

348

Effects of chamber pressure variation on the grid temperature in an inertial electrostatic confinement device  

SciTech Connect

Inertial electrostatic confinement fusion devices are compact sources of neutrons, protons, electrons, and x rays. Such sources have many applications. Improving the efficiency of the device also increases the applications of this device. Hence a thorough understanding of the operation of this device is needed. In this paper, we study the effect of chamber pressure on the temperature of the cathode. Experimentally, the grid temperature decreases as the chamber pressure increases; numerical simulations suggest that this is caused by the reduction of the hot ion current to the cathode as the pressure increases for constant power supply current. Such an understanding further supports the conclusion that the asymmetric heating of the cathode can be decreased by homogenizing the ion flow around the cathode.

Murali, S. Krupakar [Lawrenceville Plasma Physics, 128 Lincoln Blvd., Middlesex, New Jersey 08846 (United States); Emmert, G. A.; Santarius, J. F.; Kulcinski, G. L. [Fusion Technology Institute, University of Wisconsin, 1500 Engineering Drive, Madison, Wisconsin 53706 (United States)

2010-10-15

349

Memory-assisted measurement-device-independent quantum key distribution  

E-print Network

A protocol with the potential of beating the existing distance records for conventional quantum key distribution (QKD) systems is proposed. It borrows ideas from quantum repeaters by using memories in the middle of the link, and that of measurement-device-independent QKD, which only requires optical source equipment at the user's end. For certain fast memories, our scheme allows a higher repetition rate than that of quantum repeaters, thereby requiring lower coherence times. By accounting for various sources of nonideality, such as memory decoherence, dark counts, misalignment errors, and background noise, as well as timing issues with memories, we develop a mathematical framework within which we can compare QKD systems with and without memories. In particular, we show that with the state-of-the-art technology for quantum memories, it is possible to devise memory-assisted QKD systems that, at certain distances of practical interest, outperform current QKD implementations.

Christiana Panayi; Mohsen Razavi; Xiongfeng Ma; Norbert Lütkenhaus

2014-06-19

350

Field Test of Measurement-Device-Independent Quantum Key Distribution  

E-print Network

A main type of obstacles of practical applications of quantum key distribution (QKD) network is various attacks on detection. Measurement-device-independent QKD (MDIQKD) protocol is immune to all these attacks and thus a strong candidate for network security. Recently, several proof-of-principle demonstrations of MDIQKD have been performed. Although novel, those experiments are implemented in the laboratory with secure key rates less than 0.1 bps. Besides, they need manual calibration frequently to maintain the system performance. These aspects render these demonstrations far from practicability. Thus, justification is extremely crucial for practical deployment into the field environment. Here, by developing an automatic feedback MDIQKD system operated at a high clock rate, we perform a field test via deployed fiber network of 30 km total length, achieving a 16.9 bps secure key rate. The result lays the foundation for a global quantum network which can shield from all the detection-side attacks.

Yan-Lin Tang; Hua-Lei Yin; Si-Jing Chen; Yang Liu; Wei-Jun Zhang; Xiao Jiang; Lu Zhang; Jian Wang; Li-Xing You; Jian-Yu Guan; Dong-Xu Yang; Zhen Wang; Hao Liang; Zhen Zhang; Nan Zhou; Xiongfeng Ma; Teng-Yun Chen; Qiang Zhang; Jian-Wei Pan

2014-08-11

351

SiC devices for power and high-temperature applications  

Microsoft Academic Search

Silicon carbide is a semiconductor material with superior properties compared with silicon or gallium arsenide. The main advantages concern high-temperature, high-power, high-frequency, and radiation hardened applications. In the first part of the paper, the material characteristics of SiC will be reviewed from a device point of view and the main application fields for SiC devices are summarized. In the second

W. Wondrak; E. Niemann; R. Held; R. Constapel; G. Kroetz

1998-01-01

352

INNOVATIVE INSTRUMENTATION AND ANALYSIS OF THE TEMPERATURE MEASUREMENT FOR HIGH TEMPERATURE GASIFICATION  

SciTech Connect

The systematic tests of the gasifier simulator on the clean thermocouple were completed in this reporting period. Within the systematic tests on the clean thermocouple, five (5) factors were considered as the experimental parameters including air flow rate, water flow rate, fine dust particle amount, ammonia addition and high/low frequency device (electric motor). The fractional factorial design method was used in the experiment design with sixteen (16) data sets of readings. Analysis of Variances (ANOVA) was applied to the results from systematic tests. The ANOVA results show that the un-balanced motor vibration frequency did not have the significant impact on the temperature changes in the gasifier simulator. For the fine dust particles testing, the amount of fine dust particles has significant impact to the temperature measurements in the gasifier simulator. The effects of the air and water on the temperature measurements show the same results as reported in the previous report. The ammonia concentration was included as an experimental parameter for the reducing environment in this reporting period. The ammonia concentration does not seem to be a significant factor on the temperature changes. The linear regression analysis was applied to the temperature reading with five (5) factors. The accuracy of the linear regression is relatively low, which is less than 10% accuracy. Nonlinear regression was also conducted to the temperature reading with the same factors. Since the experiments were designed in two (2) levels, the nonlinear regression is not very effective with the dataset (16 readings). An extra central point test was conducted. With the data of the center point testing, the accuracy of the nonlinear regression is much better than the linear regression.

Seong W. Lee

2004-10-01

353

Silicon-On-Insulator (SOI) Devices and Mixed-Signal Circuits for Extreme Temperature Applications  

NASA Technical Reports Server (NTRS)

Electronic systems in planetary exploration missions and in aerospace applications are expected to encounter extreme temperatures and wide thermal swings in their operational environments. Electronics designed for such applications must, therefore, be able to withstand exposure to extreme temperatures and to perform properly for the duration of the missions. Electronic parts based on silicon-on-insulator (SOI) technology are known, based on device structure, to provide faster switching, consume less power, and offer better radiation-tolerance compared to their silicon counterparts. They also exhibit reduced current leakage and are often tailored for high temperature operation. However, little is known about their performance at low temperature. The performance of several SOI devices and mixed-signal circuits was determined under extreme temperatures, cold-restart, and thermal cycling. The investigations were carried out to establish a baseline on the functionality and to determine suitability of these devices for use in space exploration missions under extreme temperatures. The experimental results obtained on selected SOI devices are presented and discussed in this paper.

Patterson, Richard; Hammoud, Ahmad; Elbuluk, Malik

2008-01-01

354

Instrument for Measuring Temperature of Water  

NASA Technical Reports Server (NTRS)

A pseudo-Brewster-angle infrared radiometer has been proposed for use in noncontact measurement of the surface temperature of a large body of water (e.g., a lake or ocean). This radiometer could be situated on a waterborne, airborne, or spaceborne platform. The design of the pseudo-Brewster-angle radiometer would exploit the spectral-emissivity and polarization characteristics of water to minimize errors attributable to the emissivity of water and to the reflection of downwelling (e.g., Solar and cloud-reflected) infrared radiation. The relevant emissivity and polarization characteristics are the following: . The Brewster angle is the angle at which light polarized parallel to the plane of incidence on a purely dielectric material is not reflected. The pseudo-Brewster angle, defined for a lossy dielectric (somewhat electrically conductive) material, is the angle for which the reflectivity for parallel-polarized light is minimized. For pure water, the reflectivity for parallel-polarized light is only 2.2 x 10(exp -4) at its pseudo- Brewster angle of 51deg. The reflectivity remains near zero, several degrees off from the 51deg optimum, allowing this angle of incidence requirement to be easily achieved. . The wavelength range of interest for measuring water temperatures is 8 to 12 microns. The emissivity of water for parallel- polarized light at the pseudo-Brewster angle is greater than 0.999 in this wavelength range. The radiometer would be sensitive in the wavelength range of 8 to 12 microns, would be equipped with a polarizer to discriminate against infrared light polarized perpendicular to the plane of incidence, and would be aimed toward a body of water at the pseudo- Brewster angle (see figure). Because the infrared radiation entering the radiometer would be polarized parallel to the plane of incidence and because very little downwelling parallel-polarized radiation would be reflected into the radiometer on account of the pseudo-Brewster arrangement, the radiation received by the radiometer would consist almost entirely of thermal emission from the surface of the water. Because the emissivity of the water would be very close to 1, the water could be regarded as a close approximation of a blackbody for the purpose of computing its surface temperature from the radiometer measurements by use of the Planck radiation law.

Ryan, Robert; Nixon, Thomas; Pagnutti, Mary; Zanoni, Vicki

2003-01-01

355

Spin-transfer switching of orthogonal spin-valve devices at cryogenic temperatures  

SciTech Connect

We present the quasi-static and dynamic switching characteristics of orthogonal spin-transfer devices incorporating an out-of-plane magnetized polarizing layer and an in-plane magnetized spin valve device at cryogenic temperatures. Switching at 12?K between parallel and anti-parallel spin-valve states is investigated for slowly varied current as well as for current pulses with durations as short as 200 ps. We demonstrate 100% switching probability with current pulses 0.6?ns in duration. We also present a switching probability diagram that summarizes device switching operation under a variety of pulse durations, amplitudes, and polarities.

Ye, L., E-mail: ly17@nyu.edu; Gopman, D. B.; Rehm, L.; Backes, D.; Wolf, G.; Kent, A. D. [Department of Physics, New York University, New York, New York 10003 (United States); Ohki, T. [Raytheon BBN Technologies, Cambridge, Massachusetts 02138 (United States); Kirichenko, A. F.; Vernik, I. V.; Mukhanov, O. A. [HYPRES, 175 Clearbrook Road, Elmsford, New York 10523 (United States)

2014-05-07

356

Nanoscale holographic interferometry for strain measurements in electronic devices  

Microsoft Academic Search

Strained silicon is now an integral feature of the latest generation of transistors and electronic devices because of the associated enhancement in carrier mobility. Strain is also expected to have an important role in future devices based on nanowires and in optoelectronic components. Different strategies have been used to engineer strain in devices, leading to complex strain distributions in two

Martin Hÿtch; Florent Houdellier; Florian Hüe; Etienne Snoeck

2008-01-01

357

Surface acoustic wave devices for wireless strain measurement  

Microsoft Academic Search

Strain monitoring is a nondestructive inspection method that can reveal the redistribution of internal forces, or the presence of anomalous loadings, in structures. Surface acoustic wave (SAW) devices are small, robust, inexpensive solid-state components in which a wave propagates along the surface of a piezoelectric material, and such devices are used in large numbers commercially as delay devices and as

T.-L. Chin; Peng Zheng; Irving J. Oppenheim; David W. Greve

2010-01-01

358

STP Temperature Measurement Ideal Gas Program  

NSDL National Science Digital Library

The STP DemonIdealGas program displays a histogram of the energy of a demon that exchanges energy with an ideal gas of particles. The purpose of this simulation is to understand why the demon acts as a perfect thermometer and why its mean energy is a measure of the temperature of the gas. The default system is a one-dimensional ideal gas of N=40 particles. Additional states and parameters can be specified using the Display|Switch GUI menu item. STP DemonIdealGas is part of a suite of Open Source Physics programs that model aspects of Statistical and Thermal Physics (STP). The program is distributed as a ready-to-run (compiled) Java archive. Double-clicking the stp_DemonIdealGas.jar file will run the program if Java is installed on your computer. Additional programs can be found by searching ComPADRE for Open Source Physics, STP, or Statistical and Thermal Physics.

Gould, Harvey; Tobochnik, Jan; Christian, Wolfgang; Cox, Anne

2008-05-28

359

Device and method for the measurement of depth of interaction using co-planar electrodes  

DOEpatents

A device and method for measuring a depth of interaction of an ionizing event and improving resolution of a co-planar grid sensor (CPG) are provided. A time-of-occurrence is measured using a comparator to time the leading edge of the event pulse from the non-collecting or collecting grid. A difference signal between the grid signals obtained with a differential amplifier includes a pulse with a leading edge occurring at the time-of-detection, measured with another comparator. A timing difference between comparator outputs corresponds to the depth of interaction, calculated using a processor, which in turn weights the difference grid signal to improve spectral resolution of a CPG sensor. The device, which includes channels for grid inputs, may be integrated into an Application Specific Integrated Circuit. The combination of the device and sensor is included. An improved high-resolution CPG is provided, e.g., a gamma-ray Cadmium Zinc Telluride CPG sensor operating at room temperature.

DeGeronimo, Gianluigi (Syosset, NY)

2007-09-18

360

Room-temperature FT-luminescence analysis of Cu(In,Ga)Se{sub 2} films and devices  

SciTech Connect

The authors report a rapid, convenient luminescence technique for quality control of polycrystalline Cu(In,Ga)Se{sub 2} (CIGS) films and photovoltaic (PV) devices. The speed and convenience of the luminescence analyses were realized by using a Fourier transform (FT) Raman spectrophotometer which operates in the near-infrared (NIR) spectral region encompassing the band gap and defect levels of CIGS. With minor modifications to the FT-Raman spectrophotometer, the authors were able to detect both photoluminescence (PL) and electroluminescence (EL) from CIGS devices at room temperature. The FT-EL technique allows luminescence measurements to be made using this equipment at energies up to 1.3 eV, while the FT-PL technique is limited to energies below 1.15 eV. By increasing sensitivity and eliminating the need for sample cooling, this approach reduced the measurement time by an order of magnitude relative to comparable dispersive PL measurements. The authors used a fiberprobe accessory to the FT-Raman spectrophotometer to demonstrate that samples can be checked for uniformity at remote locations, e.g. online, using FT-PL spectroscopy. They also used a microscope accessory to obtain the PL spectra of visibly discolored regions some tens of microns in diameter on a CIGS device, and to show that these regions emit PL at significantly lower energy and intensity than nearby uniform regions of the device.

Webb, J.D.; Contreras, M.; Noufi, R. [National Renewable Energy Lab., Golden, CO (United States)

1994-12-31

361

Substrate temperature control from RHEED intensity measurements  

Microsoft Academic Search

Substrate temperature is an importance parameter controlling nucleation and growth dynamics during the thin film epitaxy in MBE system. The most covenant methods able to determine the substrate temperature is based on some calibration procedures, where substrate temperature is calculated as a function of electric power dissipated in heater system. This paper presents possibility of substrate temperature control based on

Piotr Mazurek; Andrzej Daniluk; Krzysztof Paprocki

2004-01-01

362

Nonintrusive Measurement Of Temperature Of LED Junction  

NASA Technical Reports Server (NTRS)

Temperature inferred from spectrum of emitted light. Method of determining temperature of junction based on two relevant characteristics of LED. Gap between valence and conduction electron-energy bands in LED material decreases with increasing temperature, causing wavelength of emitted photon to increase with temperature. Other, as temperature increases, non-radiative processes dissipate more of input electrical energy as heat and less as photons in band-gap wavelenth region; optical and quantum efficiencies decrease with increasing temperature. In principal, either characteristic alone used to determine temperature. However, desirable to use both to obtain indication of uncertainty.

Leidecker, Henning; Powers, Charles

1991-01-01

363

Device Performance  

SciTech Connect

In the Device Performance group, within the National Center for Photovoltaic's Measurements and Characterization Division, we measure the performance of PV cells and modules with respect to standard reporting conditions--defined as a reference temperature (25 C), total irradiance (1000 Wm-2), and spectral irradiance distribution (IEC standard 60904-3). Typically, these are ''global'' reference conditions, but we can measure with respect to any reference set. To determine device performance, we conduct two general categories of measurements: spectral responsivity (SR) and current versus voltage (I-V). We usually perform these measurements using standard procedures, but we develop new procedures when required by new technologies. We also serve as an independent facility for verifying device performance for the entire PV community. We help the PV community solve its special measurement problems, giving advice on solar simulation, instrumentation for I-V measurements, reference cells, measurement procedures, and anomalous results. And we collaborate with researchers to analyze devices and materials.

Not Available

2006-06-01

364

SMS fiber structure for temperature measurement using an OTDR  

NASA Astrophysics Data System (ADS)

A singlemode-multimode-singlemode (SMS) fiber structure for temperature measurement using an optical time domain reflectometer (OTDR)-based interrogation system is proposed. A temperature measurement range of 40 °C-195 °C with a resolution of 0.12 °C and a linearity of 0.992 could be achieved for the multimode fiber (MMF) graded index with a length of 60 mm. It was also demonstrated that two-point temperature measurement with two SMS fiber structures as temperature sensors could be made. The proposed temperature measurement system offered a high resolution and also benefited from a simple configuration with a capability of multi-point temperature measurement.

Hatta, A. M.; Indriawati, K.; Bestariyan, T.; Humada, T.; Sekartedjo

2013-09-01

365

Multispectral precise pyrometer for measurement of seawater surface temperature  

NASA Astrophysics Data System (ADS)

The paper presents selected problems referring to remote precise temperature measurements. A method of correction of temperature measurement of seawater, disturbed by sun radiation, and a method of elimination of power supply interference were discussed for multispectral IR pyrometer.

Madura, H.; Piatkowski, T.; Powiada, E.

2004-12-01

366

Uncertainty Analysis of Temperature Measurement System Using Interval Arithmetic  

Microsoft Academic Search

An uncertainty in temperature measurement system is analyzed by deriving the transfer function model using interval arithmetic. The measurement system uses Resistance Temperature Detector (RTD) as a sensor and the uncertainty assumed is structured one. Copyright © 2007 IFSA.

B. Vasuki; M. Umapathy; S. Akhilan

367

A high-precision direct current measuring device over a kiloampere range  

NASA Astrophysics Data System (ADS)

In power supply systems, a need arises for wide-band loading currents monitors with a not galvanic contact from a control circuit. The measuring device is a reaction self-regulation circuit with a compensation of the value of the measured parameter. The measuring device may find extensive application in measurements of supply currents magnets and accelerator lenses.

Voevodin, M. A.; Gusakov, Yu. V.; Korukov, N. A.; Sajfulin, Sh. Z.; Yalovoj, I. N.

368

Lumped and Distributed Parameter SPICE Models of TE Devices Considering Temperature Dependent Material Properties  

E-print Network

Based on simplified one-dimensional steady-state analysis of thermoelectric phenomena and on analogies between thermal and electrical domains, we propose both lumped and distributed parameter electrical models for thermoelectric devices. For lumped parameter models, constant values for material properties are extracted from polynomial fit curves evaluated at different module temperatures (hot side, cold side, average, and mean module temperature). For the case of distributed parameter models, material properties are calculated according to the mean temperature at each segment of a sectioned device. A couple of important advantages of the presented models are that temperature dependence of material properties is considered and that they can be easily simulated using an electronic simulation tool such as SPICE. Comparisons are made between SPICE simulations for a single-pellet module using the proposed models and with numerical simulations carried out with Mathematica software. Results illustrate accuracy of th...

Mitrani, D; Turo, A; García, M J; Chávez, J A

2008-01-01

369

Investigation of metallization schemes for high temperature devices based on silicon carbide  

Microsoft Academic Search

The suitability of several metallization schemes for high temperature sensors and devices based on silicon carbide was investigated.\\u000a Auger electron spectroscopy (AES) depth profiling was used for the detection of possible interface reactions and thermal induced\\u000a diffusion processes. Changes in the structure of the films under the influence of high temperature were observed by transmission\\u000a electron microscopy (TEM). The maximum

T. Scholz; R. Getto; K. Gottfried; G. Kurz; J. Kriz; V. Lauer

1998-01-01

370

Soil moisture inferences from thermal infrared measurements of vegetation temperatures  

NASA Technical Reports Server (NTRS)

Thermal infrared measurements of wheat (Triticum durum) canopy temperatures were used in a crop water stress index to infer root zone soil moisture. Results indicated that one time plant temperature measurement cannot produce precise estimates of root zone soil moisture due to complicating plant factors. Plant temperature measurements do yield useful qualitative information concerning soil moisture and plant condition.

Jackson, R. D. (principal investigator)

1981-01-01

371

Temperature Dependent Lifetime Measurements Fluorescence from a Phosphor  

E-print Network

Temperature Dependent Lifetime Measurements of Fluorescence from a Phosphor by Dr. James E. Parks that fluoresces when excited, (4) to measure and analyze the temperature dependence of fluorescent light lifetimes) to learn computer-based data acquisition and analysis procedures for measuring temperature dependent

Dai, Pengcheng

372

Non-intrusive temperature measurement using microscale visualization techniques  

Microsoft Academic Search

Two non-intrusive temperature measurement techniques which utilize microscale visualization techniques are developed and evaluated. A PIV-based thermometry technique is developed to simultaneously measure the temperature and velocity of the fluid for low speed flows. Laser induced fluorescence thermometry is investigated to measure the temperature of the fluid for higher speed flows. ^ ?PIV is a widely accepted tool for making

Pramod Chamarthy

2007-01-01

373

Device model for polymer light-emitting diodes: effect of temperature and oxidation  

NASA Astrophysics Data System (ADS)

We present a temperature-dependent single carrier device model for polymer light-emitting diodes. The model includes both the injection of charge carriers over a barrier and the transport of charge across the device. To test the model, the temperature dependence of an LED based on the conjugated polymer poly[2-methoxy, 5-(2'ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) with indium tin oxide (ITO) and aluminum contacts was studied. Good agreement with experiment is found using a strongly field and temperature dependent mobility. Current-voltage characteristics were fitted over a temperature range from 100 K to 300 K using three parameters: the barrier to injection, the zero-field mobility, and the field dependence of the mobility. The resulting mobility parameters have an activation energy type form and are found to vary with temperature according to previously reported results. The barrier height to injection is found to decrease strongly between 300 K and 220 K, but decreases more slowly below 220 K. This reduction with temperature is found to relate to the red-shift of the absorption peak of MEH-PPV. The model is used to fit current-voltage characteristics of aged devices. The effect of photo-oxidation is well described by the model through a reduction of mobility at constant barrier height, giving insight into the effects of the creation of charge trapping carbonyl groups in the bulk polymer on injection and transport.

Lupton, John M.; Samuel, Ifor D. W.

1999-12-01

374

Magnetic Susceptibility Measurements at Ultra-low Temperatures  

Microsoft Academic Search

We report the design and operation of a device for ac magnetic susceptibility measurements that can operate down to 1 mK. The device, a modification of the standard mutual inductance bridge, is designed with detailed consideration of the thermalization and optimization of each element. First, in order to reduce local heating, the primary coil is made with superconducting wire. Second,

L. Yin; J. S. Xia; N. S. Sullivan; V. S. Zapf; A. Paduan-Filho

2010-01-01

375

Measurement Corner: Volume, Temperature and Pressure  

ERIC Educational Resources Information Center

Boyle's Law and basic relationships between volume and pressure of a gas at constant temperature are presented. Suggests two laboratory activities for demonstrating the effect of temperature on the volume of a gas or liquid. (CS)

Teates, Thomas G.

1977-01-01

376

Room temperature device performance of electrodeposited InSb nanowire field effect transistors  

E-print Network

Room temperature device performance of electrodeposited InSb nanowire field effect transistors April 2011; published online 14 June 2011 InSb nanowires have been formed by electrodeposition in porous for future nanoelectronics applications. Compared to other common semiconductors, InSb has a high room

Chen, Yong P.

377

Ultrasonic database development for the acoustic inspection device: the velocity-attenuation measurement system (VAMS)  

NASA Astrophysics Data System (ADS)

The inspection of sealed containers is a critical task for personnel charged with enforcing government policies, maintaining public safety, and ensuring national security. The Pacific Northwest National Laboratory (PNNL) has developed a portable, handheld acoustic inspection device (AID) that provides non-invasive container interrogation and material identification capabilities. The AID technology has been deployed worldwide and user"s are providing feedback and requesting additional capabilities and functionality. Recently, PNNL has developed a laboratory-based system for automated, ultrasonic characterization of fluids to support database development for the AID. Using pulse-echo ultrasound, ultrasonic pulses are launched into a container or bulk-solid commodity. The return echoes from these pulses are analyzed in terms of time-of-flight and frequency content (as a function of temperature) to extract physical property measurements (acoustic velocity and attenuation) of the material under test. These measured values are then compared to a tailored database of materials and fluids property data acquired using the Velocity-Attenuation Measurement System (VAMS). This bench-top platform acquires key ultrasonic property measurements as a function of temperature and frequency. This paper describes the technical basis for operation of the VAMS, recent enhancements to the measurement algorithms for both the VAMS and AID technologies, and new measurement data from laboratory testing and performance demonstration activities. Applications for homeland security and counterterrorism, law enforcement, drug-interdiction and fuel transportation compliance activities will be discussed.

Diaz, Aaron A.; Burghard, Brion J.; Valencia, Juan D.; Samuel, Todd J.

2004-07-01

378

A Fiber-Bragg-Grating-Based Sensor for Simultaneous AC Current and Temperature Measurement  

Microsoft Academic Search

In this paper, a sensor that is capable of measuring both ac current and temperature using a single fiber Bragg grating (FBG) is described. The device consists of a magnetically biased magnetostrictive alloy bonded to an FBG. The magnetic field generated by the current in a specially designed coil produces internal strains in the magnetostrictive alloy which can be detected

Deborah Reilly; Andrew J. Willshire; Grzegorz Fusiek; Pawel Niewczas; James R. McDonald

2006-01-01

379

A fibre Bragg grating based sensor for simultaneous AC current and temperature measurement  

Microsoft Academic Search

In this paper, we describe a sensor capable of measuring both AC current and temperature using a single fibre Bragg grating (FBG). The device consists of a magnetically biased magnetostrictive alloy bonded to an FBG. The magnetic field generated by the current in a specially designed coil produces internal strains in the magnetostrictive alloy which can be detected by the

Deborah Reilly; Andrew J. Willshire; Grzegorz Fusiek; Pawel Niewczas; James R. McDonald

2004-01-01

380

Direct measurements of DNA-laden flows in microfluidic devices  

NASA Astrophysics Data System (ADS)

The characterization of flows containing macromolecules such as DNA is critical for the optimal design of microfluidic systems for biochemical analyses. The effects on ?-DNA transport in microscale flows are significant because the flow behavior may be influenced by molecular interactions, both viscous and elastic forces dominate inertial forces at this length scale, and the macromolecular length scale L approaches the device length scale D. Planar micro-contraction geometries (gradual and 2:1 abrupt) are used as test structures because they are canonical microfluidic components and a viscoelastic benchmark. The DNA solution is subjected to regions of elongation along the channel centerline and shear at the walls and L/D ˜ 0.12 and ˜ 0.22 for the 2:1 abrupt and gradual contraction, respectively. Digital Particle Image Velocimetry (DPIV), pressure measurements, and flow visualization are used to characterize the flows of water and semi-dilute DNA solutions over the range 0.5 < De < 180 and 0.0001 < Re < 0.9. Recirculation regions observed upstream of the contraction for semi-dilute DNA flows indicate strong elastic flow behavior. Conformational studies of DNA flows in these geometries relate molecular conformation to the velocity fields across a similar parameter range.

Gulati, Shelly

2005-11-01

381

Measurement-device-independent QKD with Modified Coherent State  

E-print Network

The measurement-device-independent quantum key distribution (MDI-QKD) protocol has been proposed for the purpose of removing the detector side channel attacks. Due to the multi-photon events of coherent states sources, real-life implementations of MDI-QKD protocol must employ decoy states to beat the photon-number-splitting attack. Decoy states for MDI-QKD based on the weak coherent states have been studied recently. In this paper, we propose to perform MDI-QKD protocol with modified coherent states (MCS) sources. We simulate the performance of MDI-QKD with the decoy states based on MCS sources. And our simulation indicates that both the secure-key rate and transmission distance can be improved evidently with MCS sources.The physics behind this improvement is that the probability of multi-photon events of the MCS is lower than that of weak coherent states while at the same time the probability of single-photon is higher.

Mo Li; Chun-Mei Zhang; Zhen-Qiang Yin; Wei Chen; Shuang Wang; Guang-Can Guo; Zheng-Fu Han

2014-02-11

382

Measurement of active shoulder proprioception: dedicated system and device.  

PubMed

Proprioception is an essential part of shoulder stability and neuromuscular control. The purpose of the study was the development of a precise system of shoulder proprioception assessment in the active mode (Propriometr). For that purpose, devices such as the electronic goniometer and computer software had been designed. A pilot study was carried out on a control group of 27 healthy subjects, the average age being 23.8 (22-29) in order to test the system. The result of the assessment was the finding of the error of active reproduction of the joint position (EARJP). EARJP was assessed for flexion, abduction, external and internal rotation. For every motion, reference positions were used at three different angles. The results showed EARJP to range in 3-6.1°. The proprioception evaluation system (propriometr) allows a precise measurement of active joint position sense. The designed system can be used to assess proprioception in both shoulder injuries and treatment. In addition, all achieved results of normal shoulders may serve as reference to be compared with the results of forthcoming studies. PMID:23412449

Lubiatowski, Przemyslaw; Ogrodowicz, Piotr; Wojtaszek, Marcin; Kaniewski, Ryszard; Stefaniak, Jakub; Dudzi?ski, Witold; Romanowski, Leszek

2013-02-01

383

High-temperature archeointensity measurements from Mesopotamia  

NASA Astrophysics Data System (ADS)

We present new archeointensity results obtained from 127 potsherds and baked brick fragments dated from the last four millennia BC which were collected from different Syrian archeological excavations. High temperature magnetization measurements were carried out using a laboratory-built triaxial vibrating sample magnetometer (Triaxe), and ancient field intensity determinations were derived from the experimental procedure described by Le Goff and Gallet [Le Goff and Gallet. Earth Planet. Sci. Lett. 229 (2004) 31-43]. As some of the studied samples were previously analyzed using the classical Thellier and Thellier [Thellier and Thellier . Ann. Geophys. 15 (1959) 285-376] method revised by Coe [Coe. J. Geophys. Res. 72 (1967) 3247-3262], a comparison of the results is made from the two methods. The differences both at the fragment and site levels are mostly within ± 5%, which strengthens the validity of the experimental procedure developed for the Triaxe. The new data help to better constrain the geomagnetic field intensity variations in Mesopotamia during archeological times, with the probable occurrence of an archeomagnetic jerk around 2800-2600 BC.

Gallet, Yves; Le Goff, Maxime

2006-01-01

384

Temperature and anisotropic-temperature relaxation measurements in cold, pure-electron plasmas  

E-print Network

Temperature and anisotropic-temperature relaxation measurements in cold, pure-electron plasmas B. R; accepted 3 January 1996 Plasma temperatures in the range 25 to 2 106 K have been measured using a cryogenic, ultra-high vacuum, pure-electron plasma trap. The rate at which the temperatures parallel

California at San Diego, University of

385

A prototype wireless inertial-sensing device for measuring toe clearance.  

PubMed

Tripping and slipping are serious health concerns for the elderly because they result in life threatening injuries i.e., fractures and high medical costs. Our recent work in detection of tripping gait patterns has demonstrated that minimum toe clearance (MTC) is a sensitive falls risk predictor. MTC measurement has previously been done in gait laboratories and on treadmills which potentially imposes controlled walking conditions. In this paper, we describe a prototype design of a wireless device for monitoring vertical toe clearance. The sensors consists of a tri-axis accelerometer and dual-axis gyroscope connected to Crossbow sensor motes for wireless data transmission. Sensor data are transmitted to a laptop and displayed on a Matlab graphic user interface (GUI). We have performed zero base and treadmill experiments to investigate sensor performance to environmental variations and compared the calculated toe clearance against measurements made by an Optotrak motion system. It was found that device outputs were approximately independent of small ambient temperature variations, had a reliable range of 20m indoors and 50m outdoors and a maximum transmission rate of 20 packets/s. Toe clearance measurements were found to follow the Optotrak measurement trend but could be improved further by dealing with double integration errors and improving data transmission rates. PMID:19163815

Lai, Daniel T H; Charry, E; Begg, R; Palaniswami, M

2008-01-01

386

Precise measurements of radial temperature gradients in the laser-heated diamond anvil cell.  

PubMed

A new spectroradiometry system specialized for measuring two-dimensional temperature gradients for samples at high pressure in the laser heated diamond anvil cell has been designed and constructed at UCLA. Emitted light intensity from sample hotspots is imaged by a videocamera for real time monitoring, an imaging spectroradiometer for temperature measurement, and a high-dynamic-range camera that examines a magnified image of the two-dimensional intensity distribution of the heated spot, yielding precise measurements of temperature gradients. With this new system, most systematic errors in temperature measurement due to chromatic aberration are bypassed. We use this system to compare several different geometries of temperature measurement found in the literature, including scanning a pinhole aperture, and narrow-slit and wide-slit entrance apertures placed before the imaging spectrometer. We find that the most accurate way of measuring a temperature is to use the spectrometer to measure an average hotspot temperature and to use information from the imaging charge coupled device to calculate the temperature distribution to the hotspot. We investigate the effects of possible wavelength- and temperature-dependent emissivity, and evaluate their errors. We apply this technique to measure the anisotropy in temperature distribution of highly oriented graphite at room temperature and also at high pressures. A comparison between model and experiment demonstrates that this system is capable of measuring thermal diffusivity in anisotropic single crystals and is also capable of measuring relative thermal diffusivity at high pressures and temperatures among different materials. This shows the possibility of using this system to provide information about thermal diffusivity of materials at high pressure and temperature. PMID:18315322

Kavner, A; Nugent, C

2008-02-01

387

Bluetooth wireless communication and 1-wire digital temperature sensors in synchronous machine rotor temperature measurement  

Microsoft Academic Search

This paper addresses the usage of digital temperature sensors in rotor temperature measurement. A rotor temperature measurement system had to be developed because of the complete synchronous machine thermal analysis. Rotor temperatures are measured using multiple DS18B20 digital thermometers and sent via a wireless link to the host. The measurement system has been mounted on a 400 kVA synchronous generator

M. Kovac?ic?; M. Vraz?ic?; I. Gas?parac

2010-01-01

388

Evaluation of a low-cost temperature measurement system for environmental applications  

Microsoft Academic Search

Thermochron iButtons incorporate the latest in digital technology, making them smaller, less expensive, durable and potentially more reliable than many other temperature logging devices. The objective of this study was to test the accuracy of an inexpensive air temperature measurement system, composed of a Thermochron iButton and radiation shield. Sixty-one iButtons were subjected to a sequence of two water baths

Jason Hubbart; Timothy Link; Colin Campbell; Doug Cobos

2005-01-01

389

Remarks on thermoelastic effects at low temperatures and quantum limits in displacement measurements  

SciTech Connect

The noise level of thermoelastic fluctuations of a mirror at low temperature was derived and introduced by M. Cerdonio et al.[Phys. Rev. D 63, 082003 (2001)]. The importance of the paper has become remarkable according to the increasing attention to the low-temperature high-precision measurement device. Here we would like to introduce the analytical form of their equation of thermoelastic noise in the integral form in order to reduce the computational labor.

Somiya, Kentaro; Kokeyama, Keiko; Nawrodt, Ronny [Waseda Institute for Advanced Study, 1-6-1 Nishiwaseda, Shinjuku, Tokyo 169-8050 (Japan); School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Institut fuer Festkoerperphysik, Friedrich-Schiller-Universitaet Jena, D-07743 Jena (Germany)

2010-12-15

390

Low-temperature bonding of poly-(methyl methacrylate) microfluidic devices under an ultrasonic field  

NASA Astrophysics Data System (ADS)

High bond strength at low temperature without shape distortion is a major goal in microfluidic device fabrication. In this paper, we present a new easy bonding method for poly-(methyl methacrylate) (PMMA) microdevices at low temperature in an ultrasonic field. The ultrasonic energy spot effect at an interface could lead to a high bond strength up to 30 mJ cm-2 at only 60 °C. This bond strength is tens of times higher than the typical value in the literature (Tsao et al 2007 Lab. Chip. 7 499). The benefit from the low bonding temperature is that no deformation of the channel was evident. Few changes in the substrate surface property were observed. The static water contact angle of the bonded substrates had a small decrease compared to that of the virgin ones. The bonded microchannel devices were not reduced in transparency and smoothness. This method is batch-production oriented because many microdevices could be bonded at one time.

Li, S. W.; Xu, J. H.; Wang, Y. J.; Lu, Y. C.; Luo, G. S.

2009-01-01

391

Assessment of a portable device for the quantitative measurement of ankle joint stiffness in spastic individuals  

E-print Network

Assessment of a portable device for the quantitative measurement of ankle joint stiffness-rater reliability. The device could easily distinguish between stiff and control ankle joints. A portable device can be a useful diagnostic tool to obtain reliable information of stiffness for the ankle joint. a b

Gorassini, Monica

392

Time interval measurement device based on surface acoustic wave filter excitation, providing 1 ps precision and stability  

SciTech Connect

This article deals with the time interval measurement device, which is based on a surface acoustic wave (SAW) filter as a time interpolator. The operating principle is based on the fact that a transversal SAW filter excited by a short pulse can generate a finite signal with highly suppressed spectra outside a narrow frequency band. If the responses to two excitations are sampled at clock ticks, they can be precisely reconstructed from a finite number of samples and then compared so as to determine the time interval between the two excitations. We have designed and constructed a two-channel time interval measurement device which allows independent timing of two events and evaluation of the time interval between them. The device has been constructed using commercially available components. The experimental results proved the concept. We have assessed the single-shot time interval measurement precision of 1.3 ps rms that corresponds to the time of arrival precision of 0.9 ps rms in each channel. The temperature drift of the measured time interval on temperature is lower than 0.5 ps/K, and the long term stability is better than {+-}0.2 ps/h. These are to our knowledge the best values reported for the time interval measurement device. The results are in good agreement with the error budget based on the theoretical analysis.

Panek, Petr; Prochazka, Ivan [Institute of Photonics and Electronics, Academy of Sciences of the Czech Republic, Chaberska 57, 182 51 Prague (Czech Republic)

2007-09-15

393

MOVPE growth of improved nonequilibium MCT device structures for near-ambient-temperature heterodyne detectors  

NASA Astrophysics Data System (ADS)

Cadmium mercury telluride (Hg1-xCdxTe or MCT) non- equilibrium detector structures which allow room temperature operation have been grown by metal-organic vapor phase epitaxy (MOVPE). These devices suppress the auger generation by reducing the intrinsic electron and hole concentrations in the active region of the device. The MCT characteristics in this region should then be determined by the extrinsic doping concentration. In order to minimize the remaining generation processes within this so called (pi) -region, it is best formed from low acceptor doped (low X1015 cm-3) MCT, with as low a trap density as possible. The p+(pi) n+ device structure which is required to achieve the non-equilibrium phenomena requires stringent control on acceptor and donor doping, as well as composition. Acceptor doping studies with trisdimethylamino arsine (DMAAs) have been performed using GaAs and CdZnTe substrates. Minority carrier lifetime results have been obtained which are near rotatively limited and comparable to As-doped, Hg-rich liquid phase epitaxy (LPE) grown layers on CdZnTe substrates. Ambient temperature, auger-suppressed devices have levels of 1/f noise which currently limit their use in imaging applications. However, they are of great interest in other applications such as approximately equals 10 micrometer negative luminescence emitter devices and heterodyne detection of 10.6 micrometer infrared (IR) radiation from carbon-dioxide lasers. Reduction in the series resistances has been achieved by utilizing a device design with a n+ MCT common which should improve the frequency response of these devices. Another design modification, predicted to reduce the leakage current, has been the introduction of low doped, wide band gap regions either side of the (pi) -region. In practice these structures have produced over an order of magnitude improvement in the leakage current characteristics.

Maxey, C. D.; Jones, C. L.; Metcalfe, N. E.; Catchpole, R. A.; Gordon, Neil J.; White, A. M.; Elliot, C. T.

1997-10-01

394

ECH Plasma Experiments on an Internal Coil Device with a High Temperature Superconductor Coil  

SciTech Connect

Self-organization related with relaxation phenomenon is playing an important role in various aspects of magnetic confined plasmas. Recently a relaxation theory including the plasma flow has been developed by Mahajan-Yoshida, and a new relaxation state has been identified. The two-fluid relaxation condition is given by {beta} + (V/V{sub A}){sup 2} = const. To study a self-organized structure with strong plasma flow, we have introduced an internal coil device. By inducing a radial electric field with appropriate methods, we could drive a toroidal plasma flow, and confine a high beta plasma in a core region. The internal coil device Mini-RT with a high temperature superconductor(HTS) coil(Rc=0.15m, Ic=50kA) has been constructed. The vacuum chamber is 1 m in diameter and {approx}0.7 m in height. The magnetic field strength near the internal coil is around 0.1 T, and a radio-frequency wave of 2.45 GHz is applied for the plasma production. We have started ECH plasma experiments with the coil supported mechanically. The electron density, which has a peak near the internal coil, is of order 10{sup 16} m{sup -3}, reaching the cut-off density of the microwave. While, the electron temperature is of order 10 eV with a broad profile. Estimated energy confinement time is of order 10{sup -(5-6)} sec. The levitation experiment of the HTS coil has been carried out. The position of the HTS coil is measured with laser sensors, and is feedback-controlled with the levitation coil current. We have succeeded to levitating the HTS coil during one hour with an accuracy of less than 20 {omega}m. A preliminary experiment for the plasma production at the floating condition of the HTS coil has been initiated. It is affirmed that the levitation system works well and plasma with separatrix configuration is produced.

Ogawa, Yuichi [University of Tokyo (Japan); Morikawa, Junji [University of Tokyo (Japan); Ohkuni, Kotaro [University of Tokyo (Japan); Yamakoshi, Shigeo [University of Tokyo (Japan); Goto, Takuya [University of Tokyo (Japan); Mito, Toshiyuki [National Institute for Fusion Science (Japan); Yanagi, Nagato [National Institute for Fusion Science (Japan); Iwakuma, Masataka [Kyushu University (Japan)

2005-01-15

395

[Physical characterization of the therapeutic device Posturomed as a measuring device--presentation of a procedure to characterize balancing ability].  

PubMed

Training measures to improve neuromuscular coordination are becoming ever more popular for both prevention and rehabilitation, not only in athletes but also patients receiving joint replacements. Numerous proprioceptive training measures and devices are used to train the sense of balance. Parameters suitable for quantifying the results of therapy are largely lacking. Herein, a simple method for quantifying the balancing on one leg using the therapeutic device (Posturomed) commonly employed to train balance in the upright stance. The horizontal movements of the oscillating suspended platform were recorded in two orthogonal directions using a non-contact measurement system. To simulate disturbance of the upright stance, a mechanical deflection device was applied to the platform. The physical characterization of the measuring system was done using rigid masses. 13 volunteers adopting a one-legged stance were investigated. The measured displacement in the medio-lateral (ML) and AP directions were used to establish a balance index. Examination of the oscillatory behaviour of the platform revealed the path signal to be a suitable parameter for analyzing the platform movements. Differences in balance characteristics between AP and ML movements could be quantified. Frontal disturbance of the upright stance is equilibrated more effectively than lateral disturbances. Combined with a non-contact path measuring system the therapeutic device is suitable for characterizing balancing ability in an upright one-legged stance. To obtain more detailed information on the neuromuscular mechanisms involved, further studies are needed. PMID:15106899

Müller, O; Günther, M; Krauss, I; Horstmann, Th

2004-03-01

396

Floating Probe Assembly for Measuring Temperature of Water  

NASA Technical Reports Server (NTRS)

A floating apparatus denoted a temperature probe aquatic suspension system (TPASS) has been developed for measuring the temperature of an ocean, lake, or other natural body of water at predetermined depths. These types of measurements are used in computer models to relate remotely sensed water-surface temperature to bulkwater temperature. Prior instruments built for the same purpose were found to give inaccurate readings because the apparatuses themselves significantly affected the temperatures of the water in their vicinities. The design of the TPASS is intended to satisfy a requirement to minimize the perturbation of the temperatures to be measured.

Stewart, Randy; Ruffin, Clyde

2003-01-01

397

Optical diagnostics for soot and temperature measurement in diesel engines  

Microsoft Academic Search

This paper reviews the optical techniques for in-cylinder combustion temperature measurement, particularly soot measurements in diesel engines. The review starts with the two-colour method for in-cylinder soot and combustion temperature measurement. The principle and implementation of the two-colour technique are described in detail. Both signal point and full-field temperature and soot measurements by the two-colour method are considered. In the

H. Zhao; N. Ladommatos

1998-01-01

398

Global trends of measured surface air temperature  

Microsoft Academic Search

We analyze surface air temperature data from available meteorological stations with principal focus on the period 1880-1985. The temperature changes at mid- and high latitude stations separated by less than 1000 km are shown to be highly correlated; at low latitudes the correlation falls off more rapidly with distance for nearby stations. We combine the station data in a way

James Hansen; Sergej Lebedeff

1987-01-01

399

27 CFR 24.170 - Measuring devices and testing instruments.  

Code of Federal Regulations, 2010 CFR

27 Alcohol, Tobacco Products...devices and testing instruments. 24.170 Section 24.170 Alcohol, Tobacco Products... (b) Testing instruments. The proprietor...for determining the alcohol content unless...

2010-04-01

400

27 CFR 24.170 - Measuring devices and testing instruments.  

Code of Federal Regulations, 2011 CFR

27 Alcohol, Tobacco Products...devices and testing instruments. 24.170 Section 24.170 Alcohol, Tobacco Products... (b) Testing instruments. The proprietor...for determining the alcohol content unless...

2011-04-01

401

27 CFR 24.170 - Measuring devices and testing instruments.  

Code of Federal Regulations, 2012 CFR

27 Alcohol, Tobacco Products...devices and testing instruments. 24.170 Section 24.170 Alcohol, Tobacco Products... (b) Testing instruments. The proprietor...for determining the alcohol content unless...

2012-04-01

402

Temperature sensitivity of capillary-driven flow: application to age monitoring devices.  

PubMed

The effects of time-dependent temperature fluctuations on surface-tension driven fluid flow inside a capillary are modeled using classical hydrodynamics. To begin, Newton's second law is evoked to derive a nondimensional equation of motion that describes the time-evolution of the fluid front position and velocity as a function of system geometry, fluid properties, and fluid temperature. This model is used to examine how temperature excursions affect the instantaneous and long-term position and velocity of the fluid front inside the capillary. Next, the effects of orientation on the movement of high viscosity fluids through a capillary are examined. From these findings, a procedure is developed for designing non-powered time-temperature integration devices for recording the cumulative temperature exposure history of an environment. PMID:22300654

Thomas, J A; Boyle, M P; Hunter, L W; Tiffany, J E

2012-04-15

403

Measurement and improvement of characteristics using optical fiber temperature sensors at cryogenic temperatures  

NASA Astrophysics Data System (ADS)

By monitoring the temperature inside cryogenic equipment such as superconducting magnet, we can detect the indication of failures and prevent the equipment suffered from damage. It is possible to measure the multipoint temperature by one optical fiber sensor. This sensor is suitable to measure the temperature at cryogenic temperatures because of low heat invasion and high voltage insulation. In this study, as for Fiber Bragg Grating as abbreviated FBG system of multipoint type, we investigated the reproducibility by measuring the temperature repeatedly, and multipoint measurement characteristics by measuring the temperature inside a cryogenic equipment with temperature gradient. We also investigated the improvement of the sensitivity for temperature at cryogenic temperatures by enhancing the thermal expansion coefficient using the coated optical fiber sensor.

Yamada, H.; Tanaka, Y.; Ogata, M.; Mizuno, K.; Nagashima, K.; Okumura, S.; Terada, Y.

2011-11-01

404

Measurement in a marine environment using low cost sensors of temperature and dissolved oxygen  

USGS Publications Warehouse

Continuous records of physical parameters of the marine environment are difficult as well as expensive to obtain. This paper describes preliminary results of an investigative program with the purpose of developing low cost time integrating measurement and averaging devices for water temperature and dissolved oxygen. Measurements were made in an estuarine area of the Chesapeake Bay over two week periods. With chemical thermometers average water temperature for the two week period was found to be equal to average water temperature measured with thermocouples plus or minus 1.0 C. The slow diffusion of oxygen through the semipermiable sides of plastic bottles permitted the use of water filled bottles to obtain averaged oxygen measurements. Oxygen measurements for two week averaging times using 500 ml polyethylene bottles were found to vary from conventionally measured and averaged dissolved oxygen by about 1.8 mg/l. ?? 1974 Estuarine Research Federation.

Godshall, F.A.; Cory, R.L.; Phinney, D.E.

1974-01-01

405

Orthogonal optimization for room temperature magnetron sputtering of ZnO:Al films for all-solid electrochromic devices  

NASA Astrophysics Data System (ADS)

In order to obtain competent and quality (high transparency, conductivity and stability) aluminium-doped zinc oxide (ZnO:Al, ZAO) films for all solid electrochromic devices, ZAO films were prepared by direct current (D.C.) reactive magnetron sputtering at room temperature based on orthogonal design. Optical and electrical property dependences of the films on the four dominant sputtering parameters: sputtering time, target-substrate distance, sputtering power and O2 flow ratio were simultaneously investigated with measured results using mathematical and statistical method. Optimal Parameters to fabricate ZAO films with optimum comprehensive performances were obtained ultimately. Resistivity and carrier concentration of ZAO film deposited with optimized parameters were 3.89 × 10-4 ? cm and 1.09 × 1021 cm-3, respectively. ZAO films with these superior properties were employed as transparent electrodes eventually in a WO3 based all-solid electrochromic device which displayed good electrochromic performance. The regulation range for transmittance in the visible region of the device was more than 50%, which was comparable to that of the device adopting indium tin oxide (ITO) films as electrodes.

Wang, Tao; Diao, Xungang; Ding, Peng

2011-02-01

406

40 CFR 91.309 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2014 CFR

...2014-07-01 2013-07-01 true Engine intake air temperature measurement...CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions § 91.309 Engine intake air temperature...

2014-07-01

407

40 CFR 91.309 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false Engine intake air temperature measurement...CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions § 91.309 Engine intake air temperature...

2010-07-01

408

40 CFR 91.309 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Engine intake air temperature measurement...CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions § 91.309 Engine intake air temperature...

2013-07-01

409

40 CFR 91.309 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2012 CFR

...2012-07-01 2012-07-01 false Engine intake air temperature measurement...CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions § 91.309 Engine intake air temperature...

2012-07-01

410

40 CFR 91.309 - Engine intake air temperature measurement.  

Code of Federal Regulations, 2011 CFR

...2011-07-01 2011-07-01 false Engine intake air temperature measurement...CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION ENGINES Emission Test Equipment Provisions § 91.309 Engine intake air temperature...

2011-07-01

411

An Update High-Temperature Superconducting Maglev Measurement System  

Microsoft Academic Search

An update high temperature superconducting Maglev measurement system (SCML-02) was successfully developed. The system includes liquid nitrogen vessel, cylinder permanent magnet (PM) or PM guideway (PMG), data collection and processing, mechanical drive and autocontrol. The liquid nitrogen vessel with high temperature superconductors (HTSCs) can be placed above or under the PM. This measurement system has other characteristics: high measurement precision,

Suyu Wang; Jiasu Wang; Changyan Deng; Yiyu Lu; Youwen Zeng; Honghai Song; Haiyu Huang; Hua Jing; Yonggang Huang; Jun Zheng; Xingzhi Wang; Ya Zhang

2007-01-01

412

Role of growth temperature on the frequency response characteristics of pentacene-based organic devices  

NASA Astrophysics Data System (ADS)

The ac frequency response characteristics (FRC) of organic thin film transistors and metal-insulator semiconductor diodes were highly improved by controlling the morphology and electrical characteristics of semiconducting pentacene films. The devices with films grown at 50 °C show much higher cutoff frequency and better frequency stability of flat-band voltage, as compared to those with films grown at other temperatures below or above. The improvement mainly originates from the maximum field effect carrier mobility of 0.78 cm2 V?1 s?1 and a small metal/organic contact resistance (Rc) obtained in the optimum thin film transistors. Our results indicate growth temperature precisely tunes the film microstructure and metal/semiconductor interface, which together determine the FRC of pentacene-based organic devices.

Shao, Yayun; Zhang, Yang; He, Wenqiang; Liu, Chuan; Minari, Takeo; Wu, Sujuan; Zeng, Min; Zhang, Zhang; Gao, Xingsen; Lu, Xubing; Liu, J.-M.

2015-03-01

413

Make the most of more-precise temperature measurements  

SciTech Connect

The last few years have seen significant advances in the ability to make accurate temperature measurements in chemical-process-industries (CPI) applications. Until the advent of self-calibrating smart temperature transmitters, precise temperature measurements were confined to the scientific laboratory. Now, it is possible to make industrial process temperature measurements with an absolute precision of better than {+-} 0.1 C. Further, it is also possible to maintain the stability of those measurements over time, in spite of the adverse conditions found in numerous CPI applications. Until now, the inaccuracy of process temperature measurements have prevented implementation of sophisticated control algorithms. With the advent of precise, stable temperature measurements, a number of process control strategies can be implemented using real-time enthalpy balances for control of batch and continuous reactions. These control strategies can result in significant improvements in both throughput and quality.

Lewis, C.W. [Accutech, Hudson, MA (United States)

1998-05-01

414

Microelectromechanical System (MEMS) Device Being Developed for Active Cooling and Temperature Control  

NASA Technical Reports Server (NTRS)

High-capacity cooling options remain limited for many small-scale applications such as microelectronic components, miniature sensors, and microsystems. A microelectromechanical system (MEMS) using a Stirling thermodynamic cycle to provide cooling or heating directly to a thermally loaded surface is being developed at the NASA Glenn Research Center to meet this need. The device can be used strictly in the cooling mode or can be switched between cooling and heating modes in milliseconds for precise temperature control. Fabrication and assembly employ techniques routinely used in the semiconductor processing industry. Benefits of the MEMS cooler include scalability to fractions of a millimeter, modularity for increased capacity and staging to low temperatures, simple interfaces, limited failure modes, and minimal induced vibration. The MEMS cooler has potential applications across a broad range of industries such as the biomedical, computer, automotive, and aerospace industries. The basic capabilities it provides can be categorized into four key areas: 1) Extended environmental temperature range in harsh environments; 2) Lower operating temperatures for electronics and other components; 3) Precision spatial and temporal thermal control for temperature-sensitive devices; and 4) The enabling of microsystem devices that require active cooling and/or temperature control. The rapidly expanding capabilities of semiconductor processing in general, and microsystems packaging in particular, present a new opportunity to extend Stirling-cycle cooling to the MEMS domain. The comparatively high capacity and efficiency possible with a MEMS Stirling cooler provides a level of active cooling that is impossible at the microscale with current state-of-the-art techniques. The MEMS cooler technology builds on decades of research at Glenn on Stirling-cycle machines, and capitalizes on Glenn s emerging microsystems capabilities.

Beach, Duane E.

2003-01-01

415

Characterization of corrosion products on a copper-containing intrauterine device during storage at room temperature.  

PubMed

This paper studies the characterization of corrosion products formed on corroded and uncorroded copper-containing intrauterine devices stored at room temperature for a period of 30 months. The experimental techniques used were X-ray photo-electron spectroscopy and Auger electron spectroscopy. The compounds found were cuprite (Cu2O) and tenorite (CuO). The latter was the main compound formed on corroded samples, forming thin tarnish films. PMID:9031726

Bastidas, J M; Simancas, J

1997-02-01

416

Measuring spinal motion in rowers: the use of an electromagnetic device  

Microsoft Academic Search

Objective. To determine whether a skin-mounted electromagnetic measurement device can be used to measure lumbar spinal motion in rowers and discriminate between variations in technique.Design. The lumbar spinal kinematics of elite level rowers were assessed with an electromagnetic device (Flock of Birds™) during ergometer training using five technique variants. The system was correlated with sagittal MRI imaging of the lumbar

Anthony M. J Bull; Alison H McGregor

2000-01-01

417

Temperature-compensated surface-acoustic-wave devices with SiO2 film overlays  

Microsoft Academic Search

Temperature-stable surface-acoustic-wave (SAW) devices have been fabricated with an rf-sputtered SiO3. film overlay on YZ LiTaO2. The material properties of this composite structure relevant to surface-acoustic-wave propagation have been thoroughly studied. For an SiO2 film thickness of approximately one-half of an acoustic wavelength, a piezoelectric coupling coefficient of 0.014 is present and the temperature stability of phase delay is similar

T. E. Parker; H. Wichansky

1979-01-01

418

Effects of nuclear radiation and elevated temperature storage on electroexplosive devices  

NASA Technical Reports Server (NTRS)

Aerospace type electroexplosive devices (EEDs) were subjected to nuclear radiation. Components and chemicals used in the EEDs were also included. The kind of radiation and total dosage administered were those which may be experienced in a space flight of 10 years duration, based on information available at this time. After irradiation, the items were stored in elevated constant-temperature ovens to accelerate early effects of the exposure to radiation. Periodically, samples were withdrawn for visual observation and testing. Significant changes occurred which were attributed to elevated-temperature storage and not radiation.

Menichelli, V. J.

1976-01-01

419

Temperature measurement. [liquid monopropellant rocket engine performance tests  

NASA Technical Reports Server (NTRS)

The design, installation, checkout, calibration, and operation of a temperature measuring system to be used during tests of a liquid monopropellant rocket engine are discussed. Appendixes include: (1) temperature measurement system elemental uncertainties, and (2) tables and equations for use with thermocouples and resistance thermometers. Design guidelines are given for the critical components of each portion of the system to provide an optimum temperature measurement system which meets the performance criteria specified.

1979-01-01

420

[Welding arc temperature field measurements based on Boltzmann spectrometry].  

PubMed

Arc plasma, as non-uniform plasma, has complicated energy and mass transport processes in its internal, so plasma temperature measurement is of great significance. Compared with absolute spectral line intensity method and standard temperature method, Boltzmann plot measuring is more accurate and convenient. Based on the Boltzmann theory, the present paper calculates the temperature distribution of the plasma and analyzes the principle of lines selection by real time scanning the space of the TIG are measurements. PMID:23240385

Si, Hong; Hua, Xue-Ming; Zhang, Wang; Li, Fang; Xiao, Xiao

2012-09-01

421

High Curie temperature drive layer materials for ion-implanted magnetic bubble devices  

NASA Technical Reports Server (NTRS)

Ion implantation of bubble garnets can lower the Curie temperature by 70 C or more, thus limiting high temperature operation of devices with ion-implanted propagation patterns. Therefore, double-layer materials were made with a conventional 2-micron bubble storage layer capped by an ion-implantable drive layer of high Curie temperature, high magnetostriction material. Contiguous disk test patterns were implanted with varying doses of a typical triple implant. Quality of propagation was judged by quasistatic tests on 8-micron period major and minor loops. Variations of magnetization, uniaxial anisotropy, implant dose, and magnetostriction were investigated to ensure optimum flux matching, good charged wall coupling, and wide operating margins. The most successful drive layer compositions were in the systems (SmDyLuCa)3(FeSi)5O12 and (BiGdTmCa)3(FeSi)5O12 and had Curie temperatures 25-44 C higher than the storage layers.

Fratello, V. J.; Wolfe, R.; Blank, S. L.; Nelson, T. J.

1984-01-01

422

High Curie temperature drive layer materials for ion-implanted magnetic bubble devices  

NASA Astrophysics Data System (ADS)

Ion implantation of bubble garnets can lower the Curie temperature by 70 C or more, thus limiting high temperature operation of devices with ion-implanted propagation patterns. Therefore, double-layer materials were made with a conventional 2-micron bubble storage layer capped by an ion-implantable drive layer of high Curie temperature, high magnetostriction material. Contiguous disk test patterns were implanted with varying doses of a typical triple implant. Quality of propagation was judged by quasistatic tests on 8-micron period major and minor loops. Variations of magnetization, uniaxial anisotropy, implant dose, and magnetostriction were investigated to ensure optimum flux matching, good charged wall coupling, and wide operating margins. The most successful drive layer compositions were in the systems (SmDyLuCa)3(FeSi)5O12 and (BiGdTmCa)3(FeSi)5O12 and had Curie temperatures 25-44 C higher than the storage layers.

Fratello, V. J.; Wolfe, R.; Blank, S. L.; Nelson, T. J.

1984-03-01

423

Metal alloy resistivity measurements at very low temperatures  

NASA Technical Reports Server (NTRS)

High speed, automated system accurately measures to approximately one percent in three minutes. System identifies materials having constant thermal or electric conductivity, predicts new material properties, develops alloys in accordance with desired specifications, and develops nondestructive devices for measuring precipitation hardening.

Childs, G. E.; Clark, A. F.; Wallace, G. H.

1971-01-01

424

Active radiometer for self-calibrated furnace temperature measurements  

DOEpatents

Radiometer with a probe beam superimposed on its field-of-view for furnace temperature measurements. The radiometer includes a heterodyne millimeter/submillimeter-wave receiver including a millimeter/submillimeter-wave source for probing. The receiver is adapted to receive radiation from a surface whose temperature is to be measured. The radiation includes a surface emission portion and a surface reflection portion which includes the probe beam energy reflected from the surface. The surface emission portion is related to the surface temperature and the surface reflection portion is related to the emissivity of the surface. The simultaneous measurement of surface emissivity serves as a real time calibration of the temperature measurement.

Woskov, Paul P. (Bedford, MA); Cohn, Daniel R. (Chestnut Hill, MA); Titus, Charles H. (Newtown Square, PA); Wittle, J. Kenneth (Chester Springs, PA); Surma, Jeffrey E. (Kennewick, WA)

1996-01-01

425

An automatic camera device for measuring waterfowl use  

USGS Publications Warehouse

A Yashica Sequelle camera was modified and equipped with a timing device so that it would take pictures automatically at 15-minute intervals. Several of these cameras were used to photograph randomly selected quadrats located in different marsh habitats. The number of birds photographed in the different areas was used as an index of waterfowl use.

Cowardin, L.M.; Ashe, J.E.

1965-01-01

426

Simple Device for Electromagnetic Interference Shielding Effectiveness Measurement  

Microsoft Academic Search

The design, construction, and testing results of a simple flanged coaxial electromagnetic interference (EMI) shielding effectiveness (SE) tester are presented in this paper. This tester is a coaxial holder with uniform diameters that maintain 50 Ohm impedance throughout the length of the device. The ends of the tester are designed to directly attach 10 dB, 50 Ohm, attenuators with standard

Horacio Vasquez; Laura Espinoza; Karen Lozano; Heinrich Foltz; Shuying Yang

2009-01-01

427

In-Situ Measurements of Organic Electronic Devices Fabricated via Transfer Printing on Flexible Substrates  

NASA Astrophysics Data System (ADS)

Transfer printing was used to fabricate high quality organic thin-film transistors (TFT) on flexible substrates. The model system of a pentacene (Pn) TFT with 600 nm thick poly(methyl methacrylate) dielectric layer and gold electrodes on a polyethylene terephthalate substrate has shown a mobility (adjusted for contact resistance) of 0.237 cm^2/Vs, on/off ratio of 10^5 and threshold voltage of -7 V. To optimize the transfer printing parameters of the Pn semiconductor layer, mobility and contact resistance were studied as a function of printing temperature and pressure. The best TFT devices resulted from printing at 120 ^oC and 600 psi. A detailed study of the effect of transfer printing on the device properties was performed via in-situ measurements of drain current (ID) as a function of both drain (VD) and gate (VG) voltages. Details of the in-situ measurements while transfer printing the Pn layer will be presented and discussed. *Work supported by the Laboratory for Physical Sciences, College Park, MD and ARDA.

Tunnell, Andrew; Hines, Daniel R.; Ballarotto, Vince W.; Breban, Mihaela; Williams, Ellen D.

2006-03-01

428

Nonequilibrium shock layer temperature profiles from arc jet radiation measurements  

NASA Astrophysics Data System (ADS)

Shock layer temperature profiles are obtained through analysis of radiation from shock layers produced by a blunt body inserted in arc jet flow. Spectral measurements have been made in a nitrogen flow of 54.4 gm/s at an enthalpy of 8.72 MJ/kg. Vibrational temperatures for N2+ are obtained by matching spectral regions from arc jet spectra with spectra generated using the NEQAIR code. Temperature profiles obtained from the radiation layers show a vibrational temperature higher than the rotational temperature near the front of the shock and both temperatures decrease as the flow approaches the body. The spectral measurements are made and analysis completed for four distances, from the surface of the blunt body. The corresponding shock layer thickness is approximately 3.6 cm. Although the shock layer appears to be in thermal nonequilibrium, the measured rotational temperature approaches the single temperature results of viscous shock layer calculations at this test condition.

Blackwell, Harvel E.; Yuen, Eric; Scott, Carl D.; Arepalli, Sivaram

1989-06-01

429

Nonequilibrium shock layer temperature profiles from arc jet radiation measurements  

NASA Technical Reports Server (NTRS)

Shock layer temperature profiles are obtained through analysis of radiation from shock layers produced by a blunt body inserted in arc jet flow. Spectral measurements have been made in a nitrogen flow of 54.4 gm/s at an enthalpy of 8.72 MJ/kg. Vibrational temperatures for N2+ are obtained by matching spectral regions from arc jet spectra with spectra generated using the NEQAIR code. Temperature profiles obtained from the radiation layers show a vibrational temperature higher than the rotational temperature near the front of the shock and both temperatures decrease as the flow approaches the body. The spectral measurements are made and analysis completed for four distances, from the surface of the blunt body. The corresponding shock layer thickness is approximately 3.6 cm. Although the shock layer appears to be in thermal nonequilibrium, the measured rotational temperature approaches the single temperature results of viscous shock layer calculations at this test condition.

Blackwell, Harvel E.; Yuen, Eric; Scott, Carl D.; Arepalli, Sivaram

1989-01-01

430

Recovery Boiler Wall Tube Temperature Measurements  

Microsoft Academic Search

Summary Thermocouple data collected from various locations in the vicinity of black liquor recovery boiler primary air ports have been analyzed using two methods, one for estimating the amount of time spent at high temperatures, and the other for estimating the number of thermal fatigue cycles. A simplified method for counting the thermal fatigue cycles is shown to match the

Gorti B. Sarma; Kimberly A. Choudhury; James R. Keiser; Frank E. Steinmoeller; Keith B. Rivers; C. Malcolm Mackenzie; Bryan B. Stone; John A. Kulig Babcock

431

Field measurement of branch circuit wire temperatures  

Microsoft Academic Search

Temperature excursions of residential branch circuit wiring under field conditions were monitored to develop a field data base needed to determine the prevailing conditions in the field and to respond to various assertions that the encapsulation of branch circuit wiring within thermal insulation is a potential hazard. Previous laboratory investigations demonstrated that buried wires, when operated continuously at rated ampacity,

T. K. Falson

1981-01-01

432

Forward voltage short-pulse technique for measuring high power laser array junction temperature  

NASA Technical Reports Server (NTRS)

The present invention relates to a method of measuring the temperature of the P-N junction within the light-emitting region of a quasi-continuous-wave or pulsed semiconductor laser diode device. A series of relatively short and low current monitor pulses are applied to the laser diode in the period between the main drive current pulses necessary to cause the semiconductor to lase. At the sufficiently low current level of the monitor pulses, the laser diode device does not lase and behaves similar to an electronic diode. The voltage across the laser diode resulting from each of these low current monitor pulses is measured with a high degree of precision. The junction temperature is then determined from the measured junction voltage using their known linear relationship.

Meadows, Byron L. (Inventor); Amzajerdian, Frazin (Inventor); Barnes, Bruce W. (Inventor); Baker, Nathaniel R. (Inventor)

2012-01-01

433

Temperature Measurement of Ceramic Materials Using a Multiwavelength Pyrometer  

NASA Technical Reports Server (NTRS)

The surface temperatures of several pure ceramic materials (alumina, beryllia, magnesia, yittria and spinel) in the shape of pellets were measured using a multiwavelength pyrometer. In one of the measurements, radiation signal collection is provided simply by an optical fiber. In the other experiments, a 4.75 inch (12 cm) parabolic mirror collects the signal for the spectrometer. Temperature measurement using the traditional one- and two-color pyrometer for these ceramic materials is difficult because of their complex optical properties, such as low emissivity which varies with both temperature and wavelength. In at least one of the materials, yittria, the detected optical emission increased as the temperature was decreased due to such emissivity variation. The reasons for such changes are not known. The multiwavelength pyrometer has demonstrated its ability to measure surface temperatures under such conditions. Platinum electrodes were embedded in the ceramic pellets for resistance measurements as the temperature changed.

Ng, Daniel; Fralick, Gustave

1999-01-01

434

Measurement and correlation of jet fuel viscosities at low temperatures  

NASA Technical Reports Server (NTRS)

Apparatus and procedures were developed to measure jet fuel viscosity for eight current and future jet fuels at temperatures from ambient to near -60 C by shear viscometry. Viscosity data showed good reproducibility even at temperatures a few degrees below the measured freezing point. The viscosity-temperature relationship could be correlated by two linear segments when plotted as a standard log-log type representation (ASTM D 341). At high temperatures, the viscosity-temperature slope is low. At low temperatures, where wax precipitation is significant, the slope is higher. The breakpoint between temperature regions is the filter flow temperature, a fuel characteristic approximated by the freezing point. A generalization of the representation for the eight experimental fuels provided a predictive correlation for low-temperature viscosity, considered sufficiently accurate for many design or performance calculations.

Schruben, D. L.

1985-01-01

435

Simulator Developed to Drastically Reduce Time of Multijunction PV Device Efficiency Measurements (Fact Sheet), NREL Highlights, Research & Development  

SciTech Connect

NREL's new simulator helps speed up research in the race to improve photovoltaic efficiency. Scientists at the National Renewable Energy Laboratory (NREL) needed a quick and accurate method to predict energy generated from multijunction photovoltaic (PV) test devices. This method had to take into account the nonlinear behavior of multijunction PV. NREL achieved this by developing the One-Sun Multi-Source Simulator (OSMSS), which reduces the time for this type of reference spectrum efficiency measurement from hours or days to minutes. The OSMSS is an automated, spectrally adjustable light source that builds a unique simulator spectrum that causes a multijunction PV device to behave as it would under a reference spectrum. This new simulator consists of four light sources separated into nine wavelength bands between 350 and 2,000 nm. The irradiance in each band is adjustable from zero to about 1.5 suns. All bands are recombined via optical fibers and integrating optics to produce a nearly 10 cm x 10 cm uniform spot. The operator simply links the OSMSS to the quantum efficiency data for the test device, and the OSMSS does the rest. The OSMSS can also determine the power as a function of the spectral irradiance (beyond the reference spectra), total irradiance, and temperature. Major components of the system were built to NREL specification by LabSphere, Inc. NREL developed a new, fully automated tool that rapidly builds a spectrum under which all junctions of a multijunction PV device behave as they would under a reference spectrum. Such a spectrum is essential to properly characterize multijunction devices. The OSMSS reduces the time for building spectra for current vs. voltage measurements from hours or days to minutes. This makes it possible to quickly characterize a multijunction device under many different conditions. The OSMSS will be an important tool to help predict the yearly energy output of a multijunction PV device in a particular environment when provided with a range of spectra and temperatures for that location.

Not Available

2011-11-01

436

Integrated optical devices based on sol - gel waveguides using the temperature dependence of the effective refractive index  

NASA Astrophysics Data System (ADS)

A possibility of designing optical waveguide devices based on sol - gel SiO2 - TiO2 films using the temperature dependence of the effective refractive index is shown. The dependences of the device characteristics on the parameters of the film and opticalsystem elements are analysed. The operation of a temperature recorder and a temperature limiter with a resolution of 0.6 K mm-1 is demonstrated. The film and output-prism parameters are optimised.

Pavlov, S. V.; Trofimov, N. S.; Chekhlova, T. K.

2014-07-01

437

Measurements of Cavitation Dose, Echogenicity, and Temperature during Ultrasound Ablation  

E-print Network

comparable to radiofrequency ablation and other bulk ablation modalities. As with other thermal ablationMeasurements of Cavitation Dose, Echogenicity, and Temperature during Ultrasound Ablation T-0586 Abstract. Ultrasound ablation experiments were performed, with simultaneous measurements of acoustic

Mast, T. Douglas

438

Device sensitive to a temperature gradient and its application for constructing a thermal fluxmeter or solar sensor  

SciTech Connect

The invention relates to a device sensitive to a temperature gradient or to a heat flow comprising at least one elementary cell formed by a thin layer made from a first electric conductor or semiconductor, such as constantan, coated with a very thin electrolytic layer of a second electric conductor or semiconductor, such as copper. It has been discovered that induced electric currents flow through the surface separating the conductors, the electric voltages observed in each of the conducting or semiconducting layers being proportional to the instantaneous spatial mean of the surface thermal gradient. The invention also relates to the application of such cells for measuring temperature gradients and heat flows and for converting heat energy into electric energy.

Cornet, M.; Ravalitera, G.; Thery, P.

1983-05-03

439

Creep measuring device for low melting point metals  

E-print Network

for low melting point metals Metal Lithium Tin Lead Cadmium Melting Temperature C 180. 54 231. 96 327. 5 320. 9 Metal Na Indium Melting Temperature C 63. 25 97. 81 156. 61 33 near the melting point. No literature has been identified...

Portal, Marc-Emmanuel Gilbert

2012-06-07

440

A two-axis goniometer for low-temperature nuclear magnetic resonance measurements on single crystals.  

PubMed

We report on the construction of a two-axis goniometer intended for low-temperature, single-crystal nuclear magnetic resonance (NMR) measurements. With the use of home-made and commercially available parts, our simple probe-head design achieves good sensitivity, while maintaining a high angular precision and the ability to orient samples also when cooled to liquid helium temperatures. The probe with the goniometer is adapted to be inserted into a commercial (4)He-flow cryostat, which fits into a wide-bore superconducting solenoid magnet. Selected examples of NMR measurements illustrate the operation of the device. PMID:23020388

Shiroka, T; Casola, F; Mesot, J; Bachmann, W; Ott, H-R

2012-09-01

441

Fiber optic pyrometer and its application in hot-blast stove temperature measurement  

NASA Astrophysics Data System (ADS)

Introduced in this paper are a technique of fiber optic dual-wavelength pyrometer and its principle, structure and characteristics. It was successfully applied under the hostile environment in hot-blast stoves to measure high-temperature. The efforts to overcome all difficulties, such as pressure, water vapor, and probe bend caused by thermal expansion, are reported in details. The resulting device is reliable, stable and accurate, and has immunity to harmful gas corrosion. The proposed pyrometer has a long lifetime. Therefore, it can replace the conventional thermo-electric-couple for temperature measurement in a blast furnace.

Li, Weilai; Jiang, Desheng; Zhu, Weijia

2004-03-01

442

Lumped and Distributed Parameter SPICE Models of TE Devices Considering Temperature Dependent Material Properties  

E-print Network

Based on simplified one-dimensional steady-state analysis of thermoelectric phenomena and on analogies between thermal and electrical domains, we propose both lumped and distributed parameter electrical models for thermoelectric devices. For lumped parameter models, constant values for material properties are extracted from polynomial fit curves evaluated at different module temperatures (hot side, cold side, average, and mean module temperature). For the case of distributed parameter models, material properties are calculated according to the mean temperature at each segment of a sectioned device. A couple of important advantages of the presented models are that temperature dependence of material properties is considered and that they can be easily simulated using an electronic simulation tool such as SPICE. Comparisons are made between SPICE simulations for a single-pellet module using the proposed models and with numerical simulations carried out with Mathematica software. Results illustrate accuracy of the distributed parameter models and show how inappropriate is to assume, in some cases, constant material parameters for an entire thermoelectric element.

D. Mitrani; J. Salazar; A. Turo; M. J. García; J. A. Chávez

2008-01-07

443

Liquid Oxygen Liquid Acquisition Device Bubble Point Tests with High Pressure LOX at Elevated Temperatures  

NASA Technical Reports Server (NTRS)

When transferring propellant in space, it is most efficient to transfer single phase liquid from a propellant tank to an engine. In earth s gravity field or under acceleration, propellant transfer is fairly simple. However, in low gravity, withdrawing single-phase fluid becomes a challenge. A variety of propellant management devices (PMD) are used to ensure single-phase flow. One type of PMD, a liquid acquisition device (LAD) takes advantage of capillary flow and surface tension to acquire liquid. The present work reports on testing with liquid oxygen (LOX) at elevated pressures (and thus temperatures) (maximum pressure 1724 kPa and maximum temperature 122K) as part of NASA s continuing cryogenic LAD development program. These tests evaluate LAD performance for LOX stored in higher pressure vessels that may be used in propellant systems using pressure fed engines. Test data shows a significant drop in LAD bubble point values at higher liquid temperatures, consistent with lower liquid surface tension at those temperatures. Test data also indicates that there are no first order effects of helium solubility in LOX on LAD bubble point prediction. Test results here extend the range of data for LOX fluid conditions, and provide insight into factors affecting predicting LAD bubble point pressures.

Jurns, John M.; Hartwig, Jason W.

2011-01-01

444

Specific capture and temperature-mediated release of cells in an aptamer-based microfluidic device  

PubMed Central

Isolation of cells from heterogeneous mixtures is critically important in both basic cell biology studies and clinical diagnostics. Cell isolation can be realized based on physical properties such as size, density and electrical properties. Alternatively, affinity binding of target cells by surface-immobilized ligands, such as antibodies, can be used to achieve specific cell isolation. Microfluidics technology has recently been used in conjunction with antibody-based affinity isolation methods to capture, purify and isolate cells with higher yield rates, better efficiencies and lower costs. However, a method that allows easy release and collection of live cells from affinity surfaces for subsequent analysis and detection has yet to be developed. This paper presents a microfluidic device that not only achieves specific affinity capture and enrichment, but also enables non-destructive, temperature-mediated release and retrieval of cells. Specific cell capture is achieved using surface-immobilized aptamers in a microchamber. Release of the captured cells is realized by a moderate temperature change, effected via integrated heaters and a temperature sensor, to reversibly disrupt the cell-aptamer interaction. Experimental results with CCRF-CEM cells have demonstrated that the device is capable of specific capture and temperature-mediated release of cells, that the released cells remain viable and that the aptamer-functionalized surface is regenerable. PMID:22854859

Zhu, Jing; Nguyen, ThaiHuu; Pei, Renjun; Stojanovic, Milan; Lin, Qiao

2014-01-01

445

Air Temperature Measurement Errors in Naturally Ventilated Radiation Shields  

Microsoft Academic Search

Two sources of systematic errors are considered for estimating air temperature. The first source is ambiguity of the definition of the standardized measurement height over vegetated surfaces of varying heights. Without such a standardization, evaluation of the horizontal air temperature gradient is contami- nated by the vertical variation of air temperature. This error is generally small in daytime unstable condi-

Reina Nakamura; L. Mahrt

2005-01-01

446

2D surface temperature measurement of plasma facing components with modulated active pyrometry  

SciTech Connect

In nuclear fusion devices, such as Tore Supra, the plasma facing components (PFC) are in carbon. Such components are exposed to very high heat flux and the surface temperature measurement is mandatory for the safety of the device and also for efficient plasma scenario development. Besides this measurement is essential to evaluate these heat fluxes for a better knowledge of the physics of plasma-wall interaction, it is also required to monitor the fatigue of PFCs. Infrared system (IR) is used to manage to measure surface temperature in real time. For carbon PFCs, the emissivity is high and known (? ? 0.8), therefore the contribution of the reflected flux from environment and collected by the IR cameras can be neglected. However, the future tokamaks such as WEST and ITER will be equipped with PFCs in metal (W and Be/W, respectively) with low and variable emissivities (? ? 0.1–0.4). Consequently, the reflected flux will contribute significantly in the collected flux by IR camera. The modulated active pyrometry, using a bicolor camera, proposed in this paper allows a 2D surface temperature measurement independently of the reflected fluxes and the emissivity. Experimental results with Tungsten sample are reported and compared with simultaneous measurement performed with classical pyrometry (monochromatic and bichromatic) with and without reflective flux demonstrating the efficiency of this method for surface temperature measurement independently of the reflected flux and the emissivity.

Amiel, S.; Loarer, T.; Pocheau, C.; Roche, H.; Gauthier, E.; Aumeunier, M.-H.; Courtois, X.; Jouve, M.; Balorin, C.; Moncada, V. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Le Niliot, C.; Rigollet, F. [Aix-Marseille Univ, IUSTI, UMR CNRS 7343, F-13453 Marseille (France)

2014-10-15

447

Contact Thermocouple Methodology and Evaluation for Temperature Measurement in the Laboratory  

NASA Technical Reports Server (NTRS)

Laboratory testing of advanced aerospace components very often requires highly accurate temperature measurement and control devices, as well as methods to precisely analyze and predict the performance of such components. Analysis of test articles depends on accurate measurements of temperature across the specimen. Where possible, this task is accomplished using many thermocouples welded directly to the test specimen, which can produce results with great precision. However, it is known that thermocouple spot welds can initiate deleterious cracks in some materials, prohibiting the use of welded thermocouples. Such is the case for the nickel-based superalloy MarM-247, which is used in the high temperature, high pressure heater heads for the Advanced Stirling Converter component of the Advanced Stirling Radioisotope Generator space power system. To overcome this limitation, a method was developed that uses small diameter contact thermocouples to measure the temperature of heater head test articles with the same level of accuracy as welded thermocouples. This paper includes a brief introduction and a background describing the circumstances that compelled the development of the contact thermocouple measurement method. Next, the paper describes studies performed on contact thermocouple readings to determine the accuracy of results. It continues on to describe in detail the developed measurement method and the evaluation of results produced. A further study that evaluates the performance of different measurement output devices is also described. Finally, a brief conclusion and summary of results is provided.

Brewer, Ethan J.; Pawlik, Ralph J.; Krause, David L.

2013-01-01

448

Global exospheric temperatures from ESRO 4 scale height measurements  

NASA Technical Reports Server (NTRS)

The scale height temperatures considered are based on molecular nitrogen measurements by the gas analyzer aboard the ESRO 4 in the altitude range from 280 to 310 km during the interval from December 1972 to April 1974, a period of low solar activity. At the altitude of measurement during the considered period, the scale height temperature is essentially the exospheric temperature. The mean scale height temperature derived from 1833 independent N2 scale heights is 708 K. It is concluded that the ESRO 4 data provides evidence of mean global temperatures of less than 800 K.

Keating, G. M.; Prior, E. J.; Lake, L. R.; Nicholson, J. Y., III; Fricke, K.

1977-01-01

449

A high temperature apparatus for measurement of the Seebeck coefficient  

SciTech Connect

A high temperature Seebeck coefficient measurement apparatus with various features to minimize typical sources of error is designed and built. Common sources of temperature and voltage measurement error are described and principles to overcome these are proposed. With these guiding principles, a high temperature Seebeck measurement apparatus with a uniaxial 4-point contact geometry is designed to operate from room temperature to over 1200 K. This instrument design is simple to operate, and suitable for bulk samples with a broad range of physical types and shapes.

Iwanaga, Shiho; Toberer, Eric S.; LaLonde, Aaron; Snyder, G. Jeffrey [Materials Science, California Institute of Technology, Pasadena, California 91125 (United States)

2011-06-15

450

Proximity effect thermometer for local temperature measurements on mesoscopic samples.  

SciTech Connect

Using the strong temperature-dependent resistance of a normal metal wire in proximity to a superconductor, we have been able to measure the local temperature of electrons heated by flowing a direct-current (dc) in a metallic wire to within a few tens of millikelvin at low temperatures. By placing two such thermometers at different parts of a sample, we have been able to measure the temperature difference induced by a dc flowing in the samples. This technique may provide a flexible means of making quantitative thermal and thermoelectric measurements on mesoscopic metallic samples.

Aumentado, J.; Eom, J.; Chandrasekhar, V.; Baldo, P. M.; Rehn, L. E.; Materials Science Division; Northwestern Univ; Univ. of Chicago

1999-11-29

451

High-temperature superconducting superconductor/normal metal/superconducting devices  

NASA Technical Reports Server (NTRS)

We describe the fabrication and characterization of superconductor/normal metal/superconductor (SNS) devices made with the high-temperature superconductor (HTS) YBa2Cu3O(7-x). Structures of YBa2Cu3O(7-x)/Au/Nb on c-axis-oriented YBa2Cu3O(7-x) were made in both sandwich and edge geometries in order to sample the HTS material both along and perpendicular to the conducting a-b planes. These devices display fairly ideal Josephson properties at 4.2 K. In addition, devices consisting of YBa2Cu3O(7-x)/YBa2Cu3O(y)/YBa2Cu3O(7-x), with a 'normal metal' layer of reduced transition temperature YBa2Cu3O(7-x) were fabricated and show a great deal of promise for applications near 77 K. Current-voltage characteristics like those of the Resistively-Shunted Junction model are observed, with strong response to 10 GHz radiation above 60 K.

Foote, M. C.; Hunt, B. D.; Bajuk, L. J.

1991-01-01

452

Autonomous System for MISSE Temperature Measurements  

NASA Technical Reports Server (NTRS)

The Materials International Space Station Experiment (MISSE) is scheduled to be deployed during the summer of 2001. This experiment is a cooperative endeavor by NASA-LaRC, NASA-GRC, NASA MSFC, NASA-JSC, the Materials Laboratory at the Air Force Research Laboratory, and the Boeing Phantom Works. The objective of the experiment is to evaluate performance, stability, and long term survivability of materials and components planned for use by NASA and DOD on future LEO, synchronous orbit, and interplanetary space missions. Temperature is an important parameter in the evaluation of space environmental effects on materials.

Harvey, G. A.; Lash, T. J.; Kinard, W. H.; Bull, K.; deGeest, F.

2001-01-01

453

Non-invasive measurement of temperature in ultrasonic hyperthermia  

Microsoft Academic Search

Techniques for focusing ultrasound beams for cancer hyperthermia by using ultrasonic lenses and ceramic radiators are reported. Studies have also been carried out on the noninvasive measurement of temperature using ultrasound for localized tumor therapy. Temperature measurement results for a bone tumor in vitro are presented and discussed.<>

V. R. Singh; S. Yadav

1988-01-01

454

Hypervascularity of the glans penis diagnosed with cutaneous temperature measurements  

Microsoft Academic Search

Hypervascularity of the penis is a complication that has been described after deep dorsal vein arterialization. We present a patient with hypervascularity of the penis which was diagnosed with cutaneous temperature measurements of the penis. Our patient underwent both pre- and post-operative cutaneous temperature measurements taken at seven locations along the shaft and glans of the penis with the Physitemp

C B Bleustein; A Melman

2002-01-01

455

A Thermally Annealed Mach-Zehnder Interferometer for High Temperature Measurement  

PubMed Central

An in-fiber Mach-Zehnder interferometer (MZI) for high temperature measurement is proposed and experimentally demonstrated. The device is constructed of a piece of thin-core fiber (TCF) sandwiched between two short sections of multimode fiber (MMF), i.e., a MMF-TCF-MMF structure. A well-defined interference spectrum is obtained owing to the core-mismatch, and the interference dips are sensitive to the ambient temperature. The experimental results show that the proposed interferometer is capable of high temperature measurement up to 875 °C with a sensitivity of 92 pm/°C over repeated measurements. The explored wavelength drop point may limit the measurement range, which can be improved by repeated thermal annealing. PMID:25093347

Feng, Zhongyao; Li, Jiacheng; Qiao, Xueguang; Li, Ling; Yang, Hangzhou; Hu, Manli

2014-01-01

456

Stand Alone Pressure Measurement Device (SAPMD) for the space shuttle Orbiter, part 1  

NASA Technical Reports Server (NTRS)

The specifications for the Stand Alone Pressure Measurement Device (SAPMD) are as follows: the SAPMD shall measure ambient pressure at the surface of the Orbiter TPS in the range of 0 to 15 pounds per square inch absolute (PSIA). Measurement will begin at solid rocket booster (SRB) ignition as sensed by appropriate vibration sensing elements in the SAPMD. Pressure and corresponding real-time data are to be recorded every one tenth second for 140 seconds and at the end of the recording period, the operation will be discontinued with the data preserved for interrogation subsequent to Orbiter re-entry and landing. The type and size of the battery shall be such as to allow the vibration sensing elements and a real-time clock to be initialized a minimum of 30 day prior to launch and still provide power as necessary to perform the 140 second data recording period after SRB ignition. Battery installation shall be in such a manner as to allow battery replacement without removing the SAPMD from its position or removing more than one TPS tile. The SAPMD must be mounted in specific locations under tile of the TPS. To accommodate such mounting, the absolute maximum physical dimensions much not exceed 6.0 inches in length, 1.5 inches in width, and 0.4 inches in height, and the device shall be of such configuration that it can be bonded to the Orbiter skin at the joint line of two TPS tiles with the pressure sensing port at the surface of the tile. The SAPMD must remain operational in the temperature range of -40 to +85 C and survive storage temperature of -55 to +125 C. The pressure port must withstand 934 C without causing damage to the TPS during entry and must remain functional at 262 C during ascent. The accuracy of the pressure measurement must be plus or minus one-half PSIA over a temperature range of 0 to +36 C. All the specifications were met and verified by prototype testing and documented in the enclosed test data. Four flight-qualified models were fabricated and of these, two were delivered and successfully flown in the cargo bay of STS-26.

Tomlinson, Bill

1989-01-01

457

Separation of temperature and emittance in remotely sensed radiance measurements  

NASA Technical Reports Server (NTRS)

The remote determination of surface temperature and surface spectral emittance by use of airborne or satellite-borne thermal infrared instruments is not straightforward. The radiance measured is a function of surface temperature, the unknown surface spectral emittance, and absorption and emission in the intervening atmosphere. With a single measurement, the solution for temperature and spectral emittance is undedetermined. This article reviews two of the early approximate methods which have been fairly widely used to approach this problem.

Kahle, Anne B.; Alley, Ronald E.

1992-01-01

458

Spectroscopic measurement of temperatures in pulsed TIG welding arcs  

NASA Astrophysics Data System (ADS)

Time resolved plasma temperatures in a pulsed tungsten-inert-gas (TIG) welding arc have been measured using optical emission spectroscopy. The peak and base pulse-averaged plasma temperatures both decrease with time after the arc ignition, and the plasma temperature decreases during the peak pulse period and increases during the base pulse period when the arc reaches the steady state. The decrease in the plasma temperature is associated with the increase in the cathode surface temperature and the decrease in the arc voltage and vice versa. The importance of the cathode surface temperature on the arc properties has been discussed.

Ma, Shuiliang; Gao, Hongming; Zheng, Senmu; Wu, Lin

2011-10-01

459

Ion flow measurements during the MHD relaxation processes in the HIST spherical torus device  

NASA Astrophysics Data System (ADS)

Plasma flow is one of the key roles in self-organization and magnetic reconnection processes of helicity-driven spherical torus (ST) and spheromak. The HIST spherical torus can form the standard ST and the flipped ST plasmas by utilizing the variation of the external toroidal field coil current. The flipped ST plasma can be generated by changing the polarity of the toroidal magnetic field during the standard ST discharge [1]. We have developed an ion Doppler spectrometer (IDS) system using a compact 16 channel photomultiplier tube (PMT) in order to measure the spatial profile of ion temperature and rotation velocity in the HIST device. The IDS system consists of a light collection system including optical fibers, 1 m-spectrometer and the PMT detector. As the results, it was observed that ion velocity was about 10 km/s in the same direction as the toroidal current and ExB direction in the standard ST discharge. The observed ion velocity agrees with Mach probe measurements. During the transition from the standard ST to the flipped ST state, the ion temperature was fluctuated and increased. The result implies an ion heating during magnetic reconnections. In addition, the toroidal direction of the ion flow was reversed. The detail physics of the observed phenomenon will be shown. [1] M. Nagata et al., Phys Rev. Lett. 90, pp. 225001-225004 (2003).

Nishioka, T.; Hashimoto, S.; Ando, K.; Kikuchi, Y.; Fukumoto, N.; Nagata, M.

2008-11-01

460

Two-dimensional phase contrast imaging for local turbulence measurements in large helical device (invited)  

SciTech Connect

Two-dimensional phase contrast imaging (2D) installed on the large helical device (LHD) is a unique diagnostic for local turbulence measurements. A 10.6 {mu}m infrared CO{sub 2} laser and 6x8 channel HgCdTe 2D detector are used. The length of the scattering volume is larger than plasma size. However, the asymmetry of turbulence structure with respect to the magnetic field and magnetic shear make local turbulence measurements possible. From a 2D image of the integrated fluctuations, the spatial cross-correlation function was estimated using time domain correlation analysis, then, the integrated 2D k-spectrum is obtained using maximum entropy method. The 2D k-spectrum is converted from Cartesian coordinates to cylindrical coordinates. Finally, the angle in cylindrical coordinate is converted to flux surface labels. The fluctuation profile over almost the entire plasma diameter can be obtained at a single moment. The measurable k-region can be varied by adjusting the detection optics. Presently, k=0.1-1.0 mm{sup -1} can be measured which is expected region of ion temperature gradient modes and trapped electron mode in LHD. The spatial resolution is 10%-50% of the minor radius.

Tanaka, K.; Michael, C. A.; Kawahata, K.; Akiyama, T.; Tokuzawa, T. [National Institute for Fusion Science, Toki 509-5292 (Japan); Vyacheslavov, L. N.; Sanin, A. L. [Budker Institute of Nuclear Physics, 630090, Novosibirsk (Russian Federation); Okajima, S. [School of Engineering, Chubu University, Kasugai 487-8501 (Japan)

2008-10-15

461

Liquidus temperature and optical properties measurement by containerless techniques  

NASA Technical Reports Server (NTRS)

Reactive alloy liquidus temperatures measured by conventional, contained techniques are often in error due to reactions with containers and gaseous impurities. This paper describes a new liquidus temperature measurement technique that avoids these problems by employing containerless processing. This technique relies on precise and accurate noncontact temperature measurements (NCTM), which are made possible by spectral emissivity values. The spectral emissivities, epsilon(sub lambda), are measured along with the optical properties (real, n, and imaginary, k, components of the index of refraction) using polarimetric techniques on electromagnetically levitated specimens. Results from work done at Vanderbilt University and Intersonics on the Ti-Al system are presented to demonstrate the above techniques.

Anderson, Collin D.

1993-01-01

462

Development of a Force Measurement Device for Lower-Body Muscular Strength Measuring of Skaters  

NASA Astrophysics Data System (ADS)

This paper presents a force measurement system that can measure a lower-body muscular strength of skaters. The precise measurement and analysis of the left and right lower-body strength of skaters is necessary, because a left/right lower-body strength balance is helpful to improve the athletes' performance and to protect them from injury. The system is constructed with a skate sliding board, a couple of sensor-units with load cell, indicator and control box, guard, force pad, and support bracket. The developed force measurement system is calibrated by the calibration setup, and the uncertainty of the force sensing unit on the left is within 0.087% and the uncertainty of the force sensing unit on the right is within 0.109%. In order to check the feasibility of the developed measurement device, a kinematic analysis is conducted with skater. As a result, the subject shows the deviation of left and right of 12.1 N with respect to average strength and 39.1 N with respect to the maximum strength. This evaluation results are reliable enough to make it possible to measure a lower-body muscular strength of skaters. The use of this measurement system will be expected to correct the posture of skaters and record the sports dynamics data for each athlete. It is believed that through the development of this equipment, skaters in elementary, middle, high schools, colleges, and the professional level have the systematic training to compete with world-class skaters.

Kim, Dong Ki; Lee, Jeong Tae

463

Temperature dependent E and G measurement of materials using ultrasonic guided waves  

NASA Astrophysics Data System (ADS)

A novel technique for measuring the moduli of elastic isotropic material as a function of temperature, using ultrasonic guided wave modes is presented here. These techniques can be used for measure the Young's modulus (E) and Shear Modulus (G) of material. Here, the L (0, 1) wave mode is used for measuring E and T(0,1) mode for G. The scope of measurement is made from room temperature to maximum utility temperature of material. In this work, the material is required in the form of a waveguide with an ultrasonic guided wave generator at one end and an embodiment (such as a notch or a bend) at the other end for obtaining reflected signals. The transducer is kept at room temperature while the end (along with the embodiment) is kept inside a heating device such as a temperature controlled furnace. The time of flight difference (?TOF), as a function of temperature, between the guided wave reflections from the embodiment and the end of the waveguide, is used to measure the material properties. The technique is based on the fact that, in addition to elongation of the waveguide, the sound speed in the materials also varies with temperature and is measurable from changes in the time of flight of signals. In addition, the ambient temperature of the waveguide end is measured using a calibrated thermocouple. Several materials were tested and the data was compared with values obtained from literature. For instance, Inconel -690 waveguide with embodiment of a 'L' bend was evaluated from 45°C to 1100°C at a frequency of 0.5 MHz L(0, 1) and T(0, 1) modes. The comparison between the literature values and the measured values were found to be in agreement with a regression correlation factor R=0.999 or better, for both E and G measurements. Advantages of the method over conventional methods of such measurements will also be discussed.

Periyannan, Suresh; Balasubramaniam, Krishnan

2014-02-01

464

AC loss in high-temperature superconducting conductors, cables and windings for power devices  

NASA Astrophysics Data System (ADS)

High-temperature superconducting (HTS) transformers and reactor coils promise decreased weight and volume and higher efficiency. A critical design parameter for such devices is the AC loss in the conductor. The state of the art for AC-loss reduction in HTS power devices is described, starting from the loss in the single HTS tape. Improved tape manufacturing techniques have led to a significant decrease in the magnetization loss. Transport-current loss is decreased by choosing the right operating current and temperature. The role of tape dimensions, filament twist and resistive matrix is discussed and a comparison is made between state-of-the-art BSCCO and YBCO tapes. In transformer and reactor coils the AC loss in the tape is influenced by adjacent tapes in the coil, fields from other coils, overcurrents and higher harmonics. These factors are accounted for by a new AC-loss prediction model. Field components perpendicular to the tape are minimized by optimizing the coil design and by flux guidance pieces. High-current windings are made of Roebel conductors with transposed tapes. The model iteratively finds the temperature distribution in the winding and predicts the onset of thermal instability. We have fabricated and tested several AC windings and used them to validate the model. Now we can confidently use the model as an engineering tool for designing HTS windings and for determining the necessary tape properties.

Oomen, M. P.; Rieger, J.; Hussennether, V.; Leghissa, M.

2004-05-01

465

High temperature rectifiers and MOS devices in 6H-silicon carbide  

NASA Astrophysics Data System (ADS)

A major emphasis in the aerospace industry has been to increase the performance and efficiency of aircraft engines (including helicopters). Most of the improvements require the engine to run hotter, be more compact and more precisely controlled. All of these requirements increase the temperature of an increasing number of electronic components on the engine. This contract involved the development of two types of solid state devices for use in various engine applications using silicon carbide which is the premiere semiconductor material for high temperature (and other) applications. One device is a high voltage, low current rectifier which can operate to at least 350 deg C for use in an igni