Sample records for temperature measurement device

  1. Noncontact temperature pattern measuring device

    NASA Technical Reports Server (NTRS)

    Elleman, D. D. (inventor); Allen, J. L. (inventor); Lee, M. C. (inventor)

    1987-01-01

    This invention relates to a noncontact imagine pyrometer system for obtaining the true temperature image of a given substance in a contactless fashion without making assumptions about localized emissivity of the substance or the uniformity of the temperature distribution. Such a contactless temperature imaging system has particular application in the study and production of many materials where the physical contact required to make a conventional temperature measurement drastically effects or contaminates the physical process being observed. Two examples where accurate temperature profiles are of critical interest are: (1) the solid-liquid phase change interface in the production of electronic materials and (2) metastable materials in the undercooling region. The apparent novelty resides in the recognition that an active pyrometer system may be advantageously adapted to perform contactless temperature imaging so that an accurate temperature profile can be obtained.

  2. Pressure and temperature measurement devices - liquid

    SciTech Connect

    Ahmed, S. [Rosemount Inc., Chanhassen, MN (United States)

    1995-12-01

    The need to measure temperature and pressure has become a fundamental and essential requirement in the process industry. This paper reviews the various pressure and temperature measurement devices used for liquid service. It looks at the principles of measurement, the types of instruments available, selection and suitability of each and also at the broad applications of these measurements for liquid service. Finally, this paper briefly discusses the future trend in instrumentation for measurements of this kind.

  3. Miniature ingestible telemeter devices to measure deep-body temperature

    NASA Technical Reports Server (NTRS)

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

    1976-01-01

    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.

  4. Silicon device performance measurements to support temperature range enhancement

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

    Silicon based power devices can be used at 200 C. The device measurements made during this program show a predictable shift in device parameters with increasing temperature. No catastrophic or abrupt changes occurred in the parameters over the temperature range. As expected, the most dramatic change was the increase in leakage currents with increasing temperature. At 200 C the leakage current was in the milliAmp range but was still several orders of magnitude lower than the on-state current capabilities of the devices under test. This increase must be considered in the design of circuits using power transistors at elevated temperature. Three circuit topologies have been prototyped using MOSFET's and IGBT's. The circuits were designed using zero current or zero voltage switching techniques to eliminate or minimize hard switching of the power transistors. These circuits have functioned properly over the temperature range. One thousand hour life data have been collected for two power supplies with no failures and no significant change in operating efficiency. While additional reliability testing should be conducted, the feasibility of designing soft switched circuits for operation at 200 C has been successfully demonstrated.

  5. Silicon device performance measurements to support temperature range enhancement

    NASA Technical Reports Server (NTRS)

    Bromstead, James; Weir, Bennett; Cosby, Melvin; Johnson, R. Wayne; Nelms, R. Mark; Askew, Ray

    1992-01-01

    Characterization results of a MOS controlled thyristor (MCTA60P60) are presented. This device is rated for 60A and for an anode to cathode voltage of -600 V. As discussed in the last report, the MCT failed during 500 V leakage tests at 200 C. In contrast to the BJT (bipolar junction transistor), MOSFET, and IGBT (insulated gate bipolar transistor) devices tested, the breakdown voltage of the MCT decreases significantly with increasing temperature.

  6. 46 CFR 154.1340 - Temperature measuring devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS...Design, Construction and Equipment Instrumentation § 154.1340 Temperature measuring...tanks type C, each cargo containment system for a design temperature colder...

  7. 46 CFR 154.1340 - Temperature measuring devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS...Design, Construction and Equipment Instrumentation § 154.1340 Temperature measuring...tanks type C, each cargo containment system for a design temperature colder...

  8. 46 CFR 154.1340 - Temperature measuring devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS...Design, Construction and Equipment Instrumentation § 154.1340 Temperature measuring...tanks type C, each cargo containment system for a design temperature colder...

  9. 46 CFR 154.1340 - Temperature measuring devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS...Design, Construction and Equipment Instrumentation § 154.1340 Temperature measuring...tanks type C, each cargo containment system for a design temperature colder...

  10. 46 CFR 154.1340 - Temperature measuring devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS...Design, Construction and Equipment Instrumentation § 154.1340 Temperature measuring...tanks type C, each cargo containment system for a design temperature colder...

  11. Silicon device performance measurements to support temperature range enhancement

    NASA Technical Reports Server (NTRS)

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

    1991-01-01

    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.

  12. A Modular High-Temperature Measurement Set-Up for Semiconductor Device Characterization

    E-print Network

    P. Borthen; G. Wachutka

    2008-01-07

    We demonstrate the capabilities of a high temperature measurement set-up recently developed at our institute. It is dedicated to the characterization of semiconductor devices and test structures in the temperature range from room temperature up to 500 degrees C and higher. A detailed description of the experimental aquipment is given. Its practical use is demonstrated by measuring temperature-dependent charcteristics of silicon VDMOSFET and IGBT devices as well as SiC-diodes. For the silicon devices, numerical simulations based on recently developed high temperature physical models were also performed in order to gain a deeper understanding of the measured data, together with a revalidation of the model parameters.

  13. Temperature measurement by IR camera of heated device to high temperature during a short time

    NASA Astrophysics Data System (ADS)

    Sonneck-Museux, Nathanaëlle; Vergé, Philippe; Judic, Jean-Pierre; Edard, Pierrick

    2015-04-01

    A device allowing heating a liquid to high temperatures during a very short time has been conceived in our laboratory. The goal of this survey is to find the suitable experimental configurations, so that tested material affected by the temperatures coved between 200 and 750°C. This study is achieved to the Solar Furnace of the DGA in Odeillo. The cavity containing the liquid is a thermocouple sleeve (capillary) in Inconel 600. Its extremity is closed tightly by a removable steel plug permitting the tightness after replenishment. An electromagnet associated to a generator of delay permit to make fall the whole after the solar irradiation in liquid nitrogen in order to stop the reaction of "deterioration" of the tested product. According to capillary dimensions and to heating time, the temperature measurement using a pyrometer is not possible. A second possibility is using thermocouple, but it is not easy to join this captor on Inconel 600. Using by infrared camera allows observing the presence or the absence of inflammation during the solar irradiation and the sleeve fall too. The measures of temperatures by thermocouple show a lot of variability. The measures comparison with those by infrared camera shows a phenomenon of "heat well". Several score of tests to the solar furnace have been achieved in different experimental configurations. Nine experimental configurations have been validated, for variable flux of 100 to 500W/cm². The observation by infrared camera permitted to validate the conceived system and to verify the homogeneity of the sleeve heated.

  14. Use of a Temperature Gradient Measuring Device in Monitoring of Diabetic and Critically Ill Patients

    Microsoft Academic Search

    V. Coulic; V. Novikov; J. Devriendt; C. Gillet; A. Bodson; E. DeKoster

    2007-01-01

    A device realizing the simultaneous measure of the central body temperature (Tc), the superficial one (Ts) and their difference (Dt), was proposed for permanent energetic balance evaluation in humans. A program was elaborated to command the intravenous delivery of insulin by a pump depending on the value and trends of Dt. The use of this device for monitoring of decompensated

  15. Silicon device performance measurements to support temperature range enhancement

    NASA Astrophysics Data System (ADS)

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

    1992-05-01

    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.

  16. Silicon device performance measurements to support temperature range enhancement

    NASA Technical Reports Server (NTRS)

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

    1992-01-01

    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.

  17. Surface-Temperature Measurement and Submicron Defect Isolation for Microelectronic Devices Using Thermoreflectance Microscopy

    NASA Astrophysics Data System (ADS)

    Ryu, Seon Young; Kim, Dong Uk; Kim, Jun Ki; Choi, Hae Young; Kim, Geon Hee; Chang, Ki Soo

    2014-07-01

    Thermal analysis of small defects becomes essential for understanding the influence of hotspots, which affect the device performance, such as the operating speed and reliability. In this paper, we demonstrate a CCD-based thermoreflectance microscopy (TRM) system as a noncontact thermal analysis technique especially for submicron defects on microelectronic devices. By employing a lock-in detection technique and temperature calibration process, the surface temperature distribution of a polysilicon microresistor and submicron defects that are not distinguishable in conventional optical microscope images can be quantitatively measured with high thermal (up to ˜ 13 mK) and spatial (˜ 670 nm) resolution. In addition, the accuracy of quantitative temperature measurement and small defect isolation by the TRM system is compared with that obtained from an infrared thermography (IRT) system.

  18. An at-sea evaluation of an infrared/resistance temperature device for air/sea-surface temperature measurements

    NASA Astrophysics Data System (ADS)

    Patterson, W. L.

    1994-03-01

    Air and sea-surface temperatures were measured and recorded by the USS Kitty Hawk's meteorological personnel during a 6-month deployment period. Using infrared/resistance temperature devices (IR/RTD) and hand-held psychrometers, air and sea-surface temperature data were compiled. In comparing these data with data collected earlier by the USS Ranger, it became apparent that the shipboard use of the IR/RTD to measure sea-surface and air temperatures was not warranted. The IR/RTD suffered mechanical and electrical failures during both the USS Kitty Hawk and USSR Ranger measurement periods. Since repair and recalibration must be done at the manufacturer's facility, the device is inappropriate for shipboard use. In addition, the design of the battery-recharging unit does not conform to shipboard requirements for electrical grounding. Borne out by both the comments of the USS Kitty Hawk oceanographer and the large number of highly suspicious readings, additional training for observers is justified. Thus, training on the proper use and care of temperature-measuring devices could be made part of the Aerographer's Mate course curriculum and shipboard performance factors.

  19. Temporal and Spatial Temperature Measurement in Insulator-Based Dielectrophoretic Devices

    PubMed Central

    2015-01-01

    Insulator-based dielectrophoresis is a relatively new analytical technique with a large potential for a number of applications, such as sorting, separation, purification, fractionation, and preconcentration. The application of insulator-based dielectrophoresis (iDEP) for biological samples, however, requires the precise control of the microenvironment with temporal and spatial resolution. Temperature variations during an iDEP experiment are a critical aspect in iDEP since Joule heating could lead to various detrimental effects hampering reproducibility. Additionally, Joule heating can potentially induce thermal flow and more importantly can degrade biomolecules and other biological species. Here, we investigate temperature variations in iDEP devices experimentally employing the thermosensitive dye Rhodamin B (RhB) and compare the measured results with numerical simulations. We performed the temperature measurement experiments at a relevant buffer conductivity range commonly used for iDEP applications under applied electric potentials. To this aim, we employed an in-channel measurement method and an alternative method employing a thin film located slightly below the iDEP channel. We found that the temperature does not deviate significantly from room temperature at 100 ?S/cm up to 3000 V applied such as in protein iDEP experiments. At a conductivity of 300 ?S/cm, such as previously used for mitochondria iDEP experiments at 3000 V, the temperature never exceeds 34 °C. This observation suggests that temperature effects for iDEP of proteins and mitochondria under these conditions are marginal. However, at larger conductivities (1 mS/cm) and only at 3000 V applied, temperature increases were significant, reaching a regime in which degradation is likely to occur. Moreover, the thin layer method resulted in lower temperature enhancement which was also confirmed with numerical simulations. We thus conclude that the thin film method is preferable providing closer agreement with numerical simulations and further since it does not depend on the iDEP channel material. Overall, our study provides a thorough comparison of two experimental techniques for direct temperature measurement, which can be adapted to a variety of iDEP applications in the future. The good agreement between simulation and experiment will also allow one to assess temperature variations for iDEP devices prior to experiments. PMID:24889741

  20. Device and method for self-verifying temperature measurement and control

    DOEpatents

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

    2002-10-29

    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.

  1. A temperature-controlled device for volumetric measurements of Helium adsorption in porous media

    E-print Network

    Cross, Benjamin; Wolf, Pierre-Etienne

    2008-01-01

    We describe a set-up for studying adsorption of helium in silica aerogels, where the adsorbed amount is easily and precisely controlled by varying the temperature of a gas reservoir between 80 K and 180 K. We present validation experiments and a first application to aerogels. This device is well adapted to study hysteresis, relaxation, and metastable states in the adsorption and desorption of fluids in porous media.

  2. A temperature-controlled device for volumetric measurements of Helium adsorption in porous media

    E-print Network

    Benjamin Cross; Laurent Puech; Pierre-Etienne Wolf

    2008-06-26

    We describe a set-up for studying adsorption of helium in silica aerogels, where the adsorbed amount is easily and precisely controlled by varying the temperature of a gas reservoir between 80 K and 180 K. We present validation experiments and a first application to aerogels. This device is well adapted to study hysteresis, relaxation, and metastable states in the adsorption and desorption of fluids in porous media.

  3. A new device for high precision in situ sediment temperature profile measurements at the seafloor

    NASA Astrophysics Data System (ADS)

    Feseker, T.; Wetzel, G.; Heesemann, B.

    2012-04-01

    In situ sediment temperature profile measurements at the seafloor provide valuable information on fluid seepage, hydrate stability, and ambient temperature of samples. In addition, it can be convenient to approximate other parameters such as concentrations of porewater constituents from temperature or temperature gradient using transfer functions if their distribution is controlled by the same processes and direct quantification involves time-consuming sampling and laboratory analyses. We present a new instrument that can be used to obtain precisely positioned sediment temperature profile measurements from the seafloor during ROV dives. Consisting of a 0.4 m-long sensor rod equipped with eight temperature sensors and a standard data logger, the new T-Stick can be operated by an ROV in a fully autonomous mode. The temperature range of the instrument is -5 °C to 35 °C and it can withstand pressures of up to 600 bar. Compared to previously used instruments, the smaller diameter of the new T-Stick reduces the thermal inertia of the lance and results in shorter equilibration times. Virtual measurements generated by a numerical model showed that the T-Stick provides highly accurate temperature profile measurements with a root mean square error of 0.0027 K for a wide range of thermal sediment properties. Modeled temperature gradients are representative of both normal deep sea settings and cold seep environments with elevated temperature gradients of up to three orders of magnitude above normal background values, which are the primary target areas for T-Stick measurements. Deviations from the true in situ temperature profiles are caused by disturbance of the temperature field by the probe itself and may lead to underestimation of gradients and curvature in the profiles. A first field test of the T-Stick was conducted at the Håkon Mosby mud volcano at 1250 m water depth on the Barents Sea slope, where the new instrument provided useful information about the origin and extent of freshly erupted mud.

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

    SciTech Connect

    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

    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.

  5. A temperature-controlled device for volumetric measurements of Helium adsorption in porous

    E-print Network

    Boyer, Edmond

    and precisely controlled by varying the temperature of a gas reservoir between 80 K and 180 K. We present vali, the adsorption curves are determined by a volumetric technique, by adding known doses of helium in successive to precisely measure hysteresis loops. Going from filling to emptying, or reversely, involves the manipulation

  6. Temperature differential detection device

    DOEpatents

    Girling, P.M.

    1986-04-22

    A temperature differential detection device for detecting the temperature differential between predetermined portions of a container wall is disclosed as comprising a Wheatstone bridge circuit for detecting resistance imbalance with a first circuit branch having a first elongated wire element mounted in thermal contact with a predetermined portion of the container wall, a second circuit branch having a second elongated wire element mounted in thermal contact with a second predetermined portion of a container wall with the wire elements having a predetermined temperature-resistant coefficient, an indicator interconnected between the first and second branches remote from the container wall for detecting and indicating resistance imbalance between the first and second wire elements, and connector leads for electrically connecting the wire elements to the remote indicator in order to maintain the respective resistance value relationship between the first and second wire elements. The indicator is calibrated to indicate the detected resistance imbalance in terms of a temperature differential between the first and second wall portions. 2 figs.

  7. Pulse flux measuring device

    DOEpatents

    Riggan, William C. (Albuquerque, NM)

    1985-01-01

    A device for measuring particle flux comprises first and second photodiode detectors for receiving flux from a source and first and second outputs for producing first and second signals representing the flux incident to the detectors. The device is capable of reducing the first output signal by a portion of the second output signal, thereby enhancing the accuracy of the device. Devices in accordance with the invention may measure distinct components of flux from a single source or fluxes from several sources.

  8. A Modular High Temperature Measurement Set-Up for Semiconductor Device Characterization

    E-print Network

    Paris-Sud XI, Université de

    -dependent characteristics of silicon VDMOSFET and IGBT devices as well as SiC-diodes. For the silicon devices, numerical rates, thermal conductivity and others may be performed. The results will be used in the refinement

  9. Portable emittance measurement device

    SciTech Connect

    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

    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.

  10. Portable emittance measurement device.

    PubMed

    Liakin, D; Seleznev, D; Orlov, A; Kuibeda, R; Kropachev, G; Kulevoy, T; Yakushin, P

    2010-02-01

    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. PMID:20192459

  11. A new device to remotely measure heat flux and skin temperature from free-swimming dolphins

    Microsoft Academic Search

    Andrew J. Westgate; William A. McLellan; Randall S. Wells; Michael D. Scott; Erin M. Meagher; D. Ann Pabst

    2007-01-01

    To enhance our understanding of how aquatic endotherms respond thermally to their environment, we present two new designs for recording heat flux (HF) and skin temperature (Ts) from the dorsal fins of free-ranging dolphins. The first package, held on by a series of small suction cups, was designed for short-term deployments on the order of hours. The second package, a

  12. Portable emittance measurement device

    Microsoft Academic Search

    D. Liakin; D. Seleznev; A. Orlov; R. Kuibeda; G. Kropachev; T. Kulevoy; P. Yakushin

    2010-01-01

    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

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

    SciTech Connect

    Anderson, Roger; Anderson, David

    2002-01-15

    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.

  14. Capacitance measuring device

    DOEpatents

    Andrews, W.H. Jr.

    1984-08-01

    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.

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

    PubMed Central

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

    2015-01-01

    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

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

    Microsoft Academic Search

    Zeng Linsuo; Wang Maojun

    2006-01-01

    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

  17. 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)

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

    2012-10-01

    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.

  18. In-situ temperature-controllable shear flow device for neutron scattering measurement--an example of aligned bicellar mixtures.

    PubMed

    Xia, Yan; Li, Ming; Ku?erka, Norbert; Li, Shutao; Nieh, Mu-Ping

    2015-02-01

    We have designed and constructed a temperature-controllable shear flow cell for in-situ study on flow alignable systems. The device has been tested in the neutron diffraction and has the potential to be applied in the small angle neutron scattering configuration to characterize the nanostructures of the materials under flow. The required sample amount is as small as 1 ml. The shear rate on the sample is controlled by the flow rate produced by an external pump and can potentially vary from 0.11 to 3.8 × 10(5) s(-1). Both unidirectional and oscillational flows are achievable by the setting of the pump. The instrument is validated by using a lipid bicellar mixture, which yields non-alignable nanodisc-like bicelles at low T and shear-alignable membranes at high T. Using the shear cell, the bicellar membranes can be aligned at 31 °C under the flow with a shear rate of 11.11 s(-1). Multiple high-order Bragg peaks are observed and the full width at half maximum of the "rocking curve" around the Bragg's condition is found to be 3.5°-4.1°. It is noteworthy that a portion of the membranes remains aligned even after the flow stops. Detailed and comprehensive intensity correction for the rocking curve has been derived based on the finite rectangular sample geometry and the absorption of the neutrons as a function of sample angle [See supplementary material at http://dx.doi.org/10.1063/1.4908165 for the detailed derivation of the absorption correction]. The device offers a new capability to study the conformational or orientational anisotropy of the solvated macromolecules or aggregates induced by the hydrodynamic interaction in a flow field. PMID:25725893

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

    PubMed

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

    2014-07-01

    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%. PMID:25085164

  20. Direct temperature mapping of nanoscale plasmonic devices.

    PubMed

    Desiatov, Boris; Goykhman, Ilya; Levy, Uriel

    2014-02-12

    Side by side with the great advantages of plasmonics in nanoscale light confinement, the inevitable ohmic loss results in significant joule heating in plasmonic devices. Therefore, understanding optical-induced heat generation and heat transport in integrated on-chip plasmonic devices is of major importance. Specifically, there is a need for in situ visualization of electromagnetic induced thermal energy distribution with high spatial resolution. This paper studies the heat distribution in silicon plasmonic nanotips. Light is coupled to the plasmonic nanotips from a silicon nanowaveguide that is integrated with the tip on chip. Heat is generated by light absorption in the metal surrounding the silicon nanotip. The steady-state thermal distribution is studied numerically and measured experimentally using the approach of scanning thermal microscopy. It is shown that following the nanoscale heat generation by a 10 mW light source within a silicon photonic waveguide the temperature in the region of the nanotip is increased by ? 15 °C compared with the ambient temperature. Furthermore, we also perform a numerical study of the dynamics of the heat transport. Given the nanoscale dimensions of the structure, significant heating is expected to occur within the time frame of picoseconds. The capability of measuring temperature distribution of plasmonic structures at the nanoscale is shown to be a powerful tool and may be used in future applications related to thermal plasmonic applications such as control heating of liquids, thermal photovoltaic, nanochemistry, medicine, heat-assisted magnetic memories, and nanolithography. PMID:24422562

  1. 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...

  2. Mirror Measurement Device

    NASA Technical Reports Server (NTRS)

    1992-01-01

    A Small Business Innovation Research (SBIR) contract led to a commercially available instrument used to measure the shape profile of mirror surfaces in scientific instruments. Bauer Associates, Inc.'s Bauer Model 200 Profilometer is based upon a different measurement concept. The local curvature of the mirror's surface is measured at many points, and the collection of data is computer processed to yield the desired shape profile. (Earlier profilometers are based on the principle of interferometry.) The system is accurate and immune to problems like vibration and turbulence. Two profilometers are currently marketed, and a third will soon be commercialized.

  3. Beta ray flux measuring device

    DOEpatents

    Impink, Jr., Albert J. (Murrysville, PA); Goldstein, Norman P. (Murrysville, PA)

    1990-01-01

    A beta ray flux measuring device in an activated member in-core instrumentation system for pressurized water reactors. The device includes collector rings positioned about an axis in the reactor's pressure boundary. Activated members such as hydroballs are positioned within respective ones of the collector rings. A response characteristic such as the current from or charge on a collector ring indicates the beta ray flux from the corresponding hydroball and is therefore a measure of the relative nuclear power level in the region of the reactor core corresponding to the specific exposed hydroball within the collector ring.

  4. Devices and methods to measure H2 and CO2 concentrations in gases released from soils and low temperature fumaroles in volcanic areas

    NASA Astrophysics Data System (ADS)

    di Martino, R. M. R.; Camarda, M.; Gurrieri, S.; Valenza, M.

    2009-04-01

    Hydrogen solubility and diffusion have a great relevance to change the redox state of magmas, usually expressed by oxygen fugacity. This influences many chemical and physical properties, such as oxidation state of multivalent elements, kind and abundance of minerals and gas species. These processes change the phase ratios into the volcanic system and so the magma movement capability toward the earth surface and the eruptive dynamics. In past studies several authors (Carapezza et al., 1980; Sato et al., 1982; Sato and McGee, 1985; Wakita et al., 1980) proposed the application of the fuel cells in order to measure reducing capacity of volcanic gases. Their found some clear correlations between variation peaks and volcanic activity but a few reducing capacity changes showed no correlation with it. In this study we characterize a fuel cell device designed to measure hydrogen concentration in a gas mixture. We present test results obtained in laboratory and in field trip, carried out to verify the major interferences of others reducing gas species, commonly present in volcanic emissions, in the measurement carried out with a hydrogen fuel cell sensor. Tests were performed at controlled temperature ad pressure conditions and at air saturated pressure vapour in the cell cathode. A new device to measure simultaneously hydrogen (H2) and carbon dioxide (CO2) concentrations in soil and in low temperature fumaroles in volcanic areas was proposed. The H2-detector is a hydrogen fuel cell, whereas CO2 is measured using an I.R. spectrometer. To build a continuous monitoring station of volcanic activity both sensors were put in a case together with a data logger. Our device has 0.2 mV ppm-1 sensitivity, accuracy of ± 5 ppm and about 10 ppm resolution whit respect to the hydrogen concentration. These instrumental characteristics were obtained applying a 500 ohm resistor to the external circuit that represents the best compromise between sensitivity, resolution, instrumental response time, and linearity of signal. We determine the CO2 concentration in the gas mixture with an I.R. spectrometer that has a measuring range of 0-100% with accuracy of ± 2% of the range and response time of 10 seconds. The laboratory results confirm our hypothesis of interference between H2, H2S and CO in the full concentration range of contaminant species. Therefore, according to our studies, the assignment of the fuel cell signal output variations only to H2 variation of concentration as in past studies, without physical separation of different reducing species may be misleading. Continuous measurements and periodical measurement field trip were performed at Torre Del Filosofo site on the upper part of the Etna volcano from the end of July to the middle October 2008. In field applications, H2S was removed with a Pb(COOH)2 trap whereas CO interference was neglected because H2/CO ratios in volcanic gases are typically high. Field time-series measurements of H2 and CO2 in gases emitted by low temperature fumaroles at Torre del Filosofo site showed a close positive correlation between explosion activity and the major peaks in the hydrogen concentration.

  5. 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)

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

    2013-10-01

    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.

  6. Measuring Temperature Reading

    NASA Technical Reports Server (NTRS)

    2003-01-01

    There are two requirements for taking a measurement of something. The first is a tool for taking a measurement. The second is scale for making sense of the numbers of the measurement. For example, a ruler is often used to measure short lengths. It is the tool for measurement. On the ruler are one or more number scales with equally spaced numbers. These numbers can be compared with numbers from any other ruler that is accurately set to the same scale. Measuring length is far simpler than measuring temperature. While there is evidence of tools for measuring length at various times in human history, tools and scales for measuring temperature do not appear until more recent human history. Early thermometers, called thermoscopes, first appear in the 1500's. They were crude instruments that were not at all accurate. Most did not even have a number scale associated with them. This made them useless for most practical purposes. Gabriel Fahrenheit created the first accurate thermometer in 1714, and the Fahrenheit temperature scale followed it in 1724. The thermometer s accuracy was based on its use of mercury, a silver colored substance that remains liquid over a wide range of temperatures but expands or contracts in a standard, predictable way with changes in temperature. To set the scale, Fahrenheit created the coldest temperature that he could. He mixed equal parts of ice, water, and salt, and then used this as the zero point, 0 degrees, of his scale. He intended to make 30 degrees the freezing point of water and 90 degrees the temperature of the human body, but he had to later revise these temperatures to be 32 degrees and 96 degrees. In the final version of the scale, the temperature of the human body became 98.6 degrees. 19th century thermoscope

  7. Finger-Circumference-Measuring Device

    NASA Technical Reports Server (NTRS)

    Le, Suy

    1995-01-01

    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.

  8. Dynamic Surface Temperature Measurements in ICs

    Microsoft Academic Search

    Josep Altet; Wilfrid Claeys; Stefan Dilhaire; Antonio Rubio

    2006-01-01

    Measuring techniques of the die surface temperature in integrated circuits are reported as very appropriate for failure analysis, for thermal characterization, and for testing modern devices. The paper is arranged as a survey of techniques oriented towards measuring the temperature dynamics of the circuit surface and presenting and discussing both the merits and drawbacks of each technique with regard to

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

    SciTech Connect

    Johnston, W.W. Jr.

    1982-01-01

    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.

  10. Nonvisual Adaptive Devices for Measuring Insulin.

    ERIC Educational Resources Information Center

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

    1993-01-01

    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)

  11. 21 CFR 882.1560 - Skin potential measurement device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1560 Skin potential measurement device. (a) Identification. A skin potential measurement device is a general diagnostic device used to measure skin voltage by means of...

  12. 21 CFR 882.1560 - Skin potential measurement device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1560 Skin potential measurement device. (a) Identification. A skin potential measurement device is a general diagnostic device used to measure skin voltage by means of...

  13. 21 CFR 882.1560 - Skin potential measurement device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1560 Skin potential measurement device. (a) Identification. A skin potential measurement device is a general diagnostic device used to measure skin voltage by means of...

  14. 21 CFR 882.1560 - Skin potential measurement device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1560 Skin potential measurement device. (a) Identification. A skin potential measurement device is a general diagnostic device used to measure skin voltage by means of...

  15. 21 CFR 882.1560 - Skin potential measurement device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1560 Skin potential measurement device. (a) Identification. A skin potential measurement device is a general diagnostic device used to measure skin voltage by means of...

  16. 21 CFR 882.1540 - Galvanic skin response measurement device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1540 Galvanic skin response measurement device. (a) Identification. A galvanic skin...

  17. 21 CFR 882.1540 - Galvanic skin response measurement device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1540 Galvanic skin response measurement device. (a) Identification. A galvanic skin...

  18. 21 CFR 882.1540 - Galvanic skin response measurement device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1540 Galvanic skin response measurement device. (a) Identification. A galvanic skin...

  19. 21 CFR 882.1540 - Galvanic skin response measurement device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1540 Galvanic skin response measurement device. (a) Identification. A galvanic skin...

  20. 21 CFR 882.1540 - Galvanic skin response measurement device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1540 Galvanic skin response measurement device. (a) Identification. A galvanic skin...

  1. Indirect Blood Pressure Measuring Device

    NASA Technical Reports Server (NTRS)

    Hum, L.; Cole, C. E.

    1973-01-01

    Design and performance of a blood pressure recording device for pediatric use are reported. A strain gage transducer with a copper-beryllium strip as force sensing element is used to monitor skin movements and to convert them into electrical signals proportional to those displacements. Experimental tests with this device in recording of force developed above the left femoral artery of a dog accurately produced a blood pressure curve.

  2. High-temperature RF probe station for device characterization through 500°C and 50 GHz

    Microsoft Academic Search

    Zachary D. Schwartz; Alan N. Downey; Samuel A. Alterovitz; George E. Ponchak

    2005-01-01

    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. The temperature is adjusted by a graphical

  3. High temperature solder device for flat cables

    NASA Technical Reports Server (NTRS)

    Haehner, Carl L. (inventor)

    1992-01-01

    A high temperature solder device for flat cables includes a microwelder, an anvil which acts as a heat sink and supports a flexible flat ribbon cable that is to be connected to a multiple pin connector. The microwelder is made from a modified commercially available resistance welding machine such as the Split Tip Electrode microwelder by Weltek, which consists of two separate electrode halves with a removable dielectric spacer in between. The microwelder is not used to weld the items together, but to provide a controlled compressive force on, and energy pulse to, a solder preform placed between a pin of the connector and a conductor of the flexible flat ribbon cable. When the microwelder is operated, an electric pulse will flow down one electrode, through the solder preform and back up the other electrode. This pulse of electrical energy will cause the solder preform to heat up and melt, joining the pin and conductor.

  4. 21 CFR 864.5950 - Blood volume measuring device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...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...

  5. 21 CFR 882.1550 - Nerve conduction velocity measurement device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...Nerve conduction velocity measurement device. 882.1550 Section...Nerve conduction velocity measurement device. (a) Identification...nerve conduction velocity measurement device is a device which...includes the stimulator and the electronic processing equipment...

  6. 21 CFR 882.1550 - Nerve conduction velocity measurement device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...Nerve conduction velocity measurement device. 882.1550 Section...Nerve conduction velocity measurement device. (a) Identification...nerve conduction velocity measurement device is a device which...includes the stimulator and the electronic processing equipment...

  7. 21 CFR 882.1550 - Nerve conduction velocity measurement device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...Nerve conduction velocity measurement device. 882.1550 Section...Nerve conduction velocity measurement device. (a) Identification...nerve conduction velocity measurement device is a device which...includes the stimulator and the electronic processing equipment...

  8. 21 CFR 882.1550 - Nerve conduction velocity measurement device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...Nerve conduction velocity measurement device. 882.1550 Section...Nerve conduction velocity measurement device. (a) Identification...nerve conduction velocity measurement device is a device which...includes the stimulator and the electronic processing equipment...

  9. 21 CFR 882.1550 - Nerve conduction velocity measurement device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...Nerve conduction velocity measurement device. 882.1550 Section...Nerve conduction velocity measurement device. (a) Identification...nerve conduction velocity measurement device is a device which...includes the stimulator and the electronic processing equipment...

  10. 21 CFR 864.5950 - Blood volume measuring device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...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...

  11. Optical fiber direct current measurement device

    Microsoft Academic Search

    Jialing Yao; Alan J. Rogers

    1996-01-01

    The possibility for using the Faraday magneto-optic effect in direct-current (dc) measurement has not been extensively studied so far. However, the demand for dc measurement in industry is rising. It is valuable to investigate the design problems of such devices. This paper presents the design of a low-cost optical-fiber direct current measurement device in a specific application which requires a

  12. Thermal Measurement Techniques in Analytical Microfluidic Devices.

    PubMed

    Davaji, Benyamin; Lee, Chung Hoon

    2015-01-01

    Thermal measurement techniques have been used for many applications such as thermal characterization of materials and chemical reaction detection. Micromachining techniques allow reduction of the thermal mass of fabricated structures and introduce the possibility to perform high sensitivity thermal measurements in the micro-scale and nano-scale devices. Combining thermal measurement techniques with microfluidic devices allows performing different analytical measurements with low sample consumption and reduced measurement time by integrating the miniaturized system on a single chip. The procedures of thermal measurement techniques for particle detection, material characterization, and chemical detection are introduced in this paper. PMID:26066563

  13. ALS insertion device block measurement and inspection

    SciTech Connect

    Marks, S.; Carrieri, J.; Cook, C.; Hassenzahl, W.V.; Hoyer, E.; Plate, D.

    1991-05-01

    The performance specifications for ALS insertion devices require detailed knowledge and strict control of the Nd-Fe-B permanent magnet blocks incorporated in these devices. This paper describes the measurement and inspection apparatus and the procedures designed to qualify and characterize these blocks. A detailed description of a new, automated Helmholtz coil facility for measurement of the three components of magnetic moment is included. Physical block inspection and magnetic moment measurement procedures are described. Together they provide a basis for qualifying blocks and for specifying placement of blocks within an insertion devices' magnetic structures. 1 ref., 4 figs.

  14. 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...

  15. Resistive Switching and Temperature-dependent Transport in HfOx-based Resistive Memory Devices

    NASA Astrophysics Data System (ADS)

    Kim, Seyoung; Ahn, Chiyui; Gokmen, Tayfun; Dial, Oliver; Ritter, Mark

    2014-03-01

    Resistive switching phenomenon in transition metal oxide materials has been studied intensively as a candidate technology for future non-volatile memory applications and electronic synapse devices. Here, we demonstrate an HfOx-based resistive memory device with rare earth metal contact in which the device resistance can be modulated with applied voltage and current. Repeatable and self-compliance switching as well as high yield and device-to-device uniformity are achieved in our devices. To understand the conduction mechanism, we perform transport measurement in multiple devices at different resistance states (initial, low and high resistance states) by probing current as a function of applied voltage at temperatures from 40K to 350K. We find that temperature insensitive tunneling conduction dominates at low temperature, while thermally activated conduction is observed at high temperature. Trap-assisted tunneling and Poole-Frenkel mechanisms are accounted for the characteristics found in different regimes.

  16. Neutron ion temperature measurement

    SciTech Connect

    Strachan, J.D.; Hendel, H.W.; Lovberg, J.; Nieschmidt, E.B.

    1986-11-01

    One important use of fusion product diagnostics is in the determination of the deuterium ion temperature from the magnitude of the 2.5 MeV d(d,n)/sup 3/He neutron emission. The detectors, calibration methods, and limitations of this technique are reviewed here with emphasis on procedures used at PPPL. In most tokamaks, the ion temperature deduced from neutrons is in reasonable agreement with the ion temperature deduced by other techniques.

  17. Measuring Soil Temperature

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil temperature is a critical factor in the germination and early growth of many crops including corn, cotton, small grains, and vegetable crops. Soil temperature strongly influences the rate of critical biological reactions in the soil such as the rates of nitrification and microbial respiration. ...

  18. An Innovative Flow-Measuring Device: Thermocouple Boundary Layer Rake

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

    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.

  19. Transient (lightning) protection for electronic measurement devices

    SciTech Connect

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

    1995-12-01

    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.

  20. The Evolution of Quantum Measuring Devices

    NASA Astrophysics Data System (ADS)

    Roth, Yehuda

    2014-03-01

    A quantum measuring device is introduced through a projective operator of any complete set of states that span the Hilbert space. Consequently, even a "bizarre" basis such as a basis of states composed of superpositions between location states, is legitimate despite its incomprehensible interpretation of a particle located in some places simultaneously. The collapse scenario that lies in the essence of any quantum measuring device, suggests that measurement is actually an interpretation process that translate reality into the predefined concepts determined by the particular selection of the basis of states. The very fact that there are bases that contradict "common sense" suggests that our brain by serving as a measuring and interpreting "device", selects only unique measuring processes. We suggest a procedure of nonlinear recursive maps that dominant an evolution of states toward few selected bases of states.

  1. Wide temperature range electronic device with lead attachment

    NASA Technical Reports Server (NTRS)

    Farrell, R. (inventor)

    1973-01-01

    A electronic device including lead attachment structure which permits operation of the devices over a wide temperature range is reported. The device comprises a core conductor having a thin coating of metal thereon whereby only a limited amount of coating material is available to form an alloy which bonds the core conductor to the device electrode, the electrode composition thus being affected only in the region adjacent to the lead.

  2. Noise measurements in charge-coupled devices

    Microsoft Academic Search

    A. M. Mohsen; M. F. Tompsett; C. H. Sequin

    1975-01-01

    Measurements of the noise levels at the output of surface and bulk channel charge-coupled devices with three-phase overlapping polysilicon electrodes are presented. Pulser noise, correlated transfer noise, shot noise, dark current noise, and electrical insertion noise at the input have been measured and studied. The dependences of the electrical insertion noise and the transfer noise on charge packet size and

  3. Antenna Devices and Measurement of Radio Emission

    E-print Network

    Erdmann, Martin

    Antenna Devices and Measurement of Radio Emission from Cosmic Ray induced Air Showers at the Pierre . . . . . . . . . . . . . . . . . . . . . . . 53 6 Antenna Theory 55 6.1 Vector Effective Length Effective Height in a Measurement Setup . . . . . . . 64 6.6.1 Thevenin Equivalent Antenna Description

  4. Uncertainties of the polarization parameters measurement in fiber optic devices

    NASA Astrophysics Data System (ADS)

    Marc, Pawel; Jaroszewicz, Leszek R.

    2005-02-01

    In the paper details of analysis measurement uncertainties of the polarization parameters in the in-line fiber optic devices were presented. For measurement of polarization parameters two fiber optic devices were used. The first one Fiber-Optic Polarization Analyzer (FOPA) and the second one Fiber-Optic Interferometric Polarization Analyzer (FOIPA). The main idea of both devices operation is comparable and consists in measurement of appropriate electric signals by using polarization sensitive detectors and basing on its calculate polarization parameters. Uncertainties of measurement these parameters were considered from standard low of propagation uncertainties point of view. The experimental results obtained from testing of laboratory analyzers allow estimating standard deviations (uncertainties) and covariances measured electric quantities. Based on these information the theoretical model of uncertainties of the polarization parameters on its ranges were proposed. Results of these analyses showed that inteferometric device allows more accurate and in shorter measurement time. The polarimetric devices gives worst accuracy what was caused mainly by temperature instabilities. However measurement uncertainties of polarization parameters of both systems are better than in bulk-optic analyzers.

  5. 21 CFR 886.4280 - Intraocular pressure measuring device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...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...

  6. 21 CFR 886.1450 - Corneal radius measuring device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...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...

  7. 21 CFR 886.4280 - Intraocular pressure measuring device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...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...

  8. 21 CFR 886.4280 - Intraocular pressure measuring device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...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...

  9. 21 CFR 886.4280 - Intraocular pressure measuring device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...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...

  10. 21 CFR 886.1450 - Corneal radius measuring device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...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...

  11. 21 CFR 864.6400 - Hematocrit measuring device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 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...

  12. 21 CFR 864.6400 - Hematocrit measuring device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 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...

  13. 21 CFR 864.5950 - Blood volume measuring device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices § 864.5950 Blood volume measuring device. (a)...

  14. 21 CFR 864.6400 - Hematocrit measuring device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 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...

  15. 21 CFR 864.5950 - Blood volume measuring device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices § 864.5950 Blood volume measuring device. (a)...

  16. 21 CFR 864.6400 - Hematocrit measuring device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 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...

  17. 21 CFR 864.5950 - Blood volume measuring device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Automated and Semi-Automated Hematology Devices § 864.5950 Blood volume measuring device. (a)...

  18. Electromagnetic pulse-induced current measurement device

    NASA Astrophysics Data System (ADS)

    Gandhi, Om P.; Chen, Jin Y.

    1991-08-01

    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.

  19. Air temperature measurement

    NASA Technical Reports Server (NTRS)

    Ballard, H. N.

    1978-01-01

    A coupled pair of identical film-mounted spherical bead thermistors serve as air temperature sensors aboard both Balloons 8-a and 8-b. The 8-a payload was reeled downward approximately 200 m beneath the balloon. The thermistor mounts were arranged in such a way so that when solar radiation was incident in a direction which was perpendicular to one film, then the direction of the incident solar ray was parallel to the second film. As the payload rotated during the flight (its rotation rate relative to the earth's magnetic field was sensed by a magnetometer), the temperature of each sensor varied depending on the orientation of the film surfaces with respect to the sun.

  20. In-Situ Optical Wafer Temperature Measurement

    NASA Astrophysics Data System (ADS)

    Adams, Bruce; Schietinger, Chuck

    2003-09-01

    The need for increasingly tighter process control is eminently apparent as semiconductor device dimensions become smaller and wafers larger. Today "Thermal Budgets" are shrinking and ramp rates are increasing throughout wafer processing. Wafer temperature is perhaps the most universally critical process variable in front-end integrated circuits (IC) manufacturing. The use of pyrometry and optical lightpipes continues to gain widespread acceptance as the standard temperature control method in many processes. Lightpipes are used for controlling temperature in chemical vapor deposition (CVD), rapid thermal processing (RTP), epitaxial film growth (EPI) and physical vapor deposition (PVD). Optical thermometry offers numerous advantages over other forms of wafer temperature measurement. This paper presents the current strengths and limitations in optical wafer temperature measurement. Many factors continue to drive the measurement technology. As IC junctions become shallower, thermal budget concerns drive process temperatures down. Processing time and ramp rates continue to shorten in particular for implant anneals. Increasingly, process control requires complete thermal histories of wafers throughout IC manufacturing. These factors and new materials (copper and low-? dielectrics) push tool manufactures and pyrometer vendors toward lower temperatures while still requiring high sensitivity, and accuracy. The accuracy of most in-situ optical temperature measurement continues to be dominated by uncertainty in wafer emissivity. Factors that limit accuracy, e.g., from wafer to wafer and from tool to tool, and advances in the technology are discussed.

  1. Experimental measurement-device-independent entanglement detection.

    PubMed

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

    2015-01-01

    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

  2. Experimental Measurement-Device-Independent Entanglement Detection

    NASA Astrophysics Data System (ADS)

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

    2015-02-01

    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.

  3. Thermal conductivity measurement of liquids in a microfluidic device

    Microsoft Academic Search

    D. Kuvshinov; M. R. Bown; J. M. MacInnes; R. W. K. Allen; R. Ge; L. Aldous; C. Hardacre; N. Doy; M. I. Newton; G. McHale

    2011-01-01

    A new microfluidic-based approach to measuring liquid thermal conductivity is developed to address the requirement in many\\u000a practical applications for measurements using small (microlitre) sample size and integration into a compact device. The approach\\u000a also gives the possibility of high-throughput testing. A resistance heater and temperature sensor are incorporated into a\\u000a glass microfluidic chip to allow transmission and detection of

  4. Wireless sensor for temperature and humidity measurement

    NASA Astrophysics Data System (ADS)

    Drumea, Andrei; Svasta, Paul

    2010-11-01

    Temperature and humidity sensors have a broad range of applications, from heating and ventilation of houses to controlled drying of fruits, vegetables or meat in food industry. Modern sensors are integrated devices, usually MEMS, factory-calibrated and with digital output of measured parameters. They can have power down modes for reduced energy consumption. Such an integrated device allows the implementation of a battery powered wireless sensor when coupled with a low power microcontroller and a radio subsystem. A radio sensor can work independently or together with others in a radio network. Presented paper focuses mainly on measurement and construction aspects of sensors for temperature and humidity designed and implemented by authors; network aspects (communication between two or more sensors) are not analyzed.

  5. An evaluation of strain measuring devices for ceramic composites

    NASA Technical Reports Server (NTRS)

    Gyekenyesi, John Z.; Bartolotta, Paul A.

    1991-01-01

    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.

  6. Noise measurements in charge-coupled devices

    Microsoft Academic Search

    A. M. Mohsen; M. F. Tompsett; C. H. Sequin

    1974-01-01

    Measurements of the noise levels at the output of surface and bulk channel charge-coupled devices with three-phase overlapping polysilicon electrodes are presented. New schemes and input circuits for low-noise electrical insertion of the signal charge are discussed. Our measurements indicate that the noise levels due to the intrinsic noise sources (transfer and storage noise) agree with our physical understanding of

  7. Validity of Devices That Assess Body Temperature During Outdoor Exercise in the Heat

    PubMed Central

    Casa, Douglas J; Becker, Shannon M; Ganio, Matthew S; Brown, Christopher M; Yeargin, Susan W; Roti, Melissa W; Siegler, Jason; Blowers, Julie A; Glaviano, Neal R; Huggins, Robert A; Armstrong, Lawrence E; Maresh, Carl M

    2007-01-01

    Context: Rectal temperature is recommended by the National Athletic Trainers' Association as the criterion standard for recognizing exertional heat stroke, but other body sites commonly are used to measure temperature. Few authors have assessed the validity of the thermometers that measure body temperature at these sites in athletic settings. Objective: To assess the validity of commonly used temperature devices at various body sites during outdoor exercise in the heat. Design: Observational field study. Setting: Outdoor athletic facilities. Patients or Other Participants: Fifteen men and 10 women (age = 26.5 ± 5.3 years, height = 174.3 ± 11.1 cm, mass = 72.73 ± 15.95 kg, body fat = 16.2 ± 5.5%). Intervention(s): We simultaneously tested inexpensive and expensive devices orally and in the axillary region, along with measures of aural, gastrointestinal, forehead, temporal, and rectal temperatures. Temporal temperature was measured according to the instruction manual and a modified method observed in medical tents at local road races. We also measured forehead temperatures directly on the athletic field (other measures occurred in a covered pavilion) where solar radiation was greater. Rectal temperature was the criterion standard used to assess the validity of all other devices. Subjects' temperatures were measured before exercise, every 60 minutes during 180 minutes of exercise, and every 20 minutes for 60 minutes of postexercise recovery. Temperature devices were considered invalid if the mean bias (average difference between rectal temperature and device temperature) was greater than ±0.27°C (±0.5°F). Main Outcome Measure(s): Temperature from each device at each site and time point. Results: Mean bias for the following temperatures was greater than the allowed limit of ±0.27°C (±0.5°F): temperature obtained via expensive oral device (?1.20°C [?2.17°F]), inexpensive oral device (?1.67°C [?3.00°F]), expensive axillary device (?2.58°C [?4.65°F]), inexpensive axillary device (?2.07°C [?3.73°F]), aural method (?1.00°C [?1.80°F]), temporal method according to instruction manual (?1.46°C [?2.64°F]), modified temporal method (?1.36°C [?2.44°F]), and forehead temperature on the athletic field (0.60°C [1.08°F]). Mean bias for gastrointestinal temperature (?0.19°C [?0.34°F]) and forehead temperature in the pavillion (?0.14°C [?0.25°F]) was less than the allowed limit of ±0.27°C (±0.5°F). Forehead temperature depended on the setting in which it was measured and showed greater variation than other temperatures. Conclusions: Compared with rectal temperature (the criterion standard), gastrointestinal temperature was the only measurement that accurately assessed core body temperature. Oral, axillary, aural, temporal, and field forehead temperatures were significantly different from rectal temperature and, therefore, are considered invalid for assessing hyperthermia in individuals exercising outdoors in the heat. PMID:18059987

  8. The measurement of low temperatures

    Microsoft Academic Search

    Robert Berman

    1973-01-01

    In the rapidly advancing field of cryogenic engineering and research the accurate measurement of very low temperatures has\\u000a become increasingly important. Alloys of gold with small amounts of iron have very large and reproducible thermoelectric powers\\u000a in this range and are successfully used as the active limbs of sensitive and stable low temperature thermocouples.

  9. Integrated Emissivity And Temperature Measurement

    DOEpatents

    Poulsen, Peter (Livermore, CA)

    2005-11-08

    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.

  10. Containerless high temperature property measurements

    NASA Technical Reports Server (NTRS)

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

    1991-01-01

    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.

  11. Precision of Four Acoustic Bone Measurement Devices

    NASA Technical Reports Server (NTRS)

    Miller, Christopher; Rianon, Nahid; Feiveson, Alan; Shackelford, Linda; LeBlanc, Adrian

    2000-01-01

    Though many studies have quantified the precision of various acoustic bone measurement devices, it is difficult to directly compare the results among the studies, because they used disparate subject pools, did not specify the estimation methodology, or did not use consistent definitions for various precision characteristics. In this study, we used a repeated measures design protocol to directly determine the precision characteristics of four acoustic bone measurement devices: the Mechanical Response Tissue Analyzer (MRTA), the UBA-575+, the SoundScan 2000 (S2000), and the Sahara Ultrasound Bone Analyzer. Ten men and ten women were scanned on all four devices by two different operators at five discrete time points: Week 1, Week 2, Week 3, Month 3 and Month 6. The percent coefficient of variation (%CV) and standardized coefficient of variation were computed for the following precision characteristics: interoperator effect, operator-subject interaction, short-term error variance, and long-term drift. The MRTA had high interoperator errors for its ulnar and tibial stiffness measures and a large long-term drift in its tibial stiffness measurement. The UBA-575+ exhibited large short-term error variances and long-term drift for all three of its measurements. The S2000's tibial speed of sound measurement showed a high short-term error variance and a significant operator-subject interaction but very good values (less than 1%) for the other precision characteristics. The Sahara seemed to have the best overall performance, but was hampered by a large %CV for short-term error variance in its broadband ultrasound attenuation measure.

  12. Precision of Four Acoustic Bone Measurement Devices

    NASA Technical Reports Server (NTRS)

    Miller, Christopher; Feiveson, Alan H.; Shackelford, Linda; Rianon, Nahida; LeBlanc, Adrian

    2000-01-01

    Though many studies have quantified the precision of various acoustic bone measurement devices, it is difficult to directly compare the results among the studies, because they used disparate subject pools, did not specify the estimation methodology, or did not use consistent definitions for various precision characteristics. In this study, we used a repeated measures design protocol to directly determine the precision characteristics of four acoustic bone measurement devices: the Mechanical Response Tissue Analyzer (MRTA), the UBA-575+, the SoundScan 2000 (S2000), and the Sahara Ultrasound Done Analyzer. Ten men and ten women were scanned on all four devices by two different operators at five discrete time points: Week 1, Week 2, Week 3, Month 3 and Month 6. The percent coefficient of variation (%CV) and standardized coefficient of variation were computed for the following precision characteristics: interoperator effect, operator-subject interaction, short-term error variance, and long-term drift, The MRTA had high interoperator errors for its ulnar and tibial stiffness measures and a large long-term drift in its tibial stiffness measurement. The UBA-575+ exhibited large short-term error variances and long-term drift for all three of its measurements. The S2000's tibial speed of sound measurement showed a high short-term error variance and a significant operator-subject interaction but very good values ( < 1%) for the other precision characteristics. The Sahara seemed to have the best overall performance, but was hampered by a large %CV for short-term error variance in its broadband ultrasound attenuation measure.

  13. Fabrication Technology and Measurement of Coupled Quantum Dot Devices

    NASA Astrophysics Data System (ADS)

    Burkhardt, Martin

    1995-01-01

    This thesis describes the fabrication and measurement of planar tunneling devices. X-ray lithography was used to define gate patterns in order to achieve lateral electrostatic confinement in a two-dimensional electron gas. Technologies were developed for the printing of features with linewidths of 50 nm and below, a lithographic resolution which is necessary for the fabrication of narrow tunneling barriers. Development of technologies such as this can also be used for large -scale fabrication of silicon and GaAs devices and circuits with critical dimensions of 100 nm and below. Quantum dots, in which the capacitances to the dot were minimized, were fabricated using high resolution lithography. Decreased capacitances to the dot increase the charging energy of a quantum dot, making it possible to observe single electron effects at elevated temperatures. The conductance of a device, featuring eight electrodes to control size and shape of a quantum dot, was measured in a Heliox insertion probe at a temperature of 300 mK. Measurements of several quantum dot sizes were performed and the results were discussed. The same device was biased to produce two unequal quantum dots in series. The results are discussed and compared with theoretical predictions. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.).

  14. Magnetic measurements on insertion devices at NSLS

    SciTech Connect

    Decker, G.; Galayda, J.; Kitamura, M.; Solomon, L.

    1988-01-01

    Magnetic measurements on three insertion devices for use in the NSLS x-ray ring are described. Hall probes were used for field mapping, and rotating long coils were used to determine integrated multipole coefficients. Results are presented for an iron pole-REC hybrid undulator, a vanadium permendur pole-REC wiggler and a 5 Tesla superconducting wiggler. 6 refs., 8 figs., 2 tabs.

  15. Novel Electrical Measurement Techniques for Silicon Devices

    NASA Astrophysics Data System (ADS)

    Elhami Khorasani, Arash

    Semiconductor manufacturing economics necessitate the development of innovative device measurement techniques for quick assessment of products. Several novel electrical measurement techniques will be proposed for screening silicon device parameters. The studied parameters range from oxide reliability, and carrier lifetime in MOS capacitors to the power MOSFET reverse recovery. It will be shown that positive charge trapping is a dominant process when thick oxides are stressed through the ramped voltage test (RVT). Exploiting the physics behind positive charge generation/trapping at high electric fields, a fast I-V measurement technique is proposed that can be used to effectively distinguish the ultra-thick oxides' intrinsic quality at low electric fields. Next, two novel techniques will be presented for studying the carrier lifetime in MOS Capacitor devices. It will be shown that the deep-level transient spectroscopy (DLTS) can be applied to MOS test structures as a swift mean for screening the generation lifetime. Recombination lifetime will also be addressed by introducing the optically-excited MOS technique as a promising tool. The last part of this work is devoted to the reverse recovery behavior of the body diode of power MOSFETs. The correct interpretation of the LDMOS reverse recovery is challenging and requires special attention. A simple approach will be presented to extract meaningful lifetime values from the reverse recovery of LDMOS body-diodes exploiting their gate voltage and the magnitude of the reverse bias.

  16. 27 CFR 25.42 - Testing of measuring devices.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Measurement of Beer § 25.42 Testing of measuring devices. (a...device such as a meter or gauge glass is used to measure beer, the brewer shall periodically test the...

  17. 27 CFR 25.42 - Testing of measuring devices.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS BEER Measurement of Beer § 25.42 Testing of measuring devices. (a...device such as a meter or gauge glass is used to measure beer, the brewer shall periodically test the...

  18. Thin film materials and devices for resistive temperature sensing applications

    NASA Astrophysics Data System (ADS)

    Basantani, Hitesh A.

    Thin films of vanadium oxide (VOx) and hydrogenated amorphous silicon (a-Si:H) are the two dominant material systems used in resistive infrared radiation detectors (microbolometers) for sensing long wave infrared (LWIR) wavelengths in the 8--14 microm range. Typical thin films of VO x (x < 2) currently used in the bolometer industry have a magnitude of temperature coefficient of resistance (TCR) between 2%/K -- 3%/K. In contrast, thin films of hydrogenated germanium (SiGe:H) have |TCR| between 3%/K to 4%/K. Devices made from either of these materials have resulted in similar device performance with NETD ? 25 mK. The performance of the microbolometers is limited by the electronic noise, especially 1/f noise. Therefore, regardless of the choice of bolometer sensing material and read out circuitry, manufacturers are constantly striving to reduce 1/f noise while simultaneously increasing TCR to give better signal to noise ratios in their bolometers and ultimately, better image quality with more thermal information to the end user. In this work, thin films of VOx and hydrogenated germanium (Ge:H), having TCR values > 4 %/K are investigated as potential candidates for higher sensitivity next generation of microbolometers. Thin films of VO x were deposited by Biased Target Ion Beam Deposition (BTIBD) (˜85 nm thick). Electrical characterization of lateral resistor structures showed resistivity ranging from 104 O--cm to 2.1 x 104 O--cm, TCR varying from --4%/K to --5%/K, normalized Hooge parameter (alphaH/n) of 5 x 10 -21 to 5 x 10-18 cm3. Thin films of Ge:H were deposited by plasma enhanced chemical vapor deposition (PECVD) by incorporating an increasing amount of crystal fraction in the growing thin films. Thin films of Ge:H having a mixed phase, amorphous + nanocrystalline, having a |TCR| > 6 %/K were deposited with resistivity < 2,300 O--cm and a normalized Hooge's parameter 'alphaH/n' < 2 x 10-20 cm3. Higher TCR materials are desired, however, such materials have higher resistivity and therefore unacceptable large electrical resistance in a lateral resistor configuration. This work looks at an alternate bolometer device design which incorporates higher TCR materials in a vertically integrated configuration. Thin films of high TCR hydrogenated germanium (Ge:H, |TCR| > 6%/K) and vanadium oxide (VOx, TCR > 5%/K) were integrated in lateral and through film configuration. The electrical performance of the vertically integrated devices is compared with lateral resistance structures. It was confirmed experimentally that the device impedance was significantly lowered while maintaining the signal to noise ratio of the lateral resistor configuration. The vertically integrated devices allow higher device currents without any increase in self heating. These structures may help reduce integration time and may result in higher frame rate. Finally, one dimensional arrays were fabricated using both lateral and vertically integrated configurations and their performance was evaluated. It was found that the performance of the lateral devices was limited by noise floor of the measurement setup used. However, due to the lower impedance of the vertically integrated resistors, a higher signal and therefore higher signal to noise ratio could be obtained. These vertically integrated devices exhibited low RMS noise values of 12 mK.

  19. Skin friction measuring device for aircraft

    NASA Technical Reports Server (NTRS)

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

    1980-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

    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.

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

    Microsoft Academic Search

    S. Suda; B. Keisch

    1993-01-01

    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:

  2. Temperature measurement during microwave processing

    SciTech Connect

    Darby, G.; Clark, D.E.; DiFiore, R.; Foltz, D. [Univ. of Florida, Gainesville, FL (United States)] [and others

    1995-12-31

    Many ceramic materials have been fabricated using sol-gel processing where the starting materials consist of a liquid organic precursor mixed with water and alcohol. The initial stages in sol-gel reactions require temperatures in the range of 100{degrees}C or less, and therefore appear ideally suited for processing in a conventional microwave oven. In this paper we evaluate the use of several types of thermocouple geometries for measuring the temperature of liquids, including tetraethylorthosilicate (TEOS) during microwave heating. The boiling point of water is used as a reference on which to base the accuracy of our measurements.

  3. Development of an Ultrasonic Airflow Measurement Device for Ducted Air

    PubMed Central

    Raine, Andrew B.; Aslam, Nauman; Underwood, Christopher P.; Danaher, Sean

    2015-01-01

    In this study, an in-duct ultrasonic airflow measurement device has been designed, developed and tested. The airflow measurement results for a small range of airflow velocities and temperatures show that the accuracy was better than 3.5% root mean square (RMS) when it was tested within a round or square duct compared to the in-line Venturi tube airflow meter used for reference. This proof of concept device has provided evidence that with further development it could be a low-cost alternative to pressure differential devices such as the orifice plate airflow meter for monitoring energy efficiency performance and reliability of ventilation systems. The design uses a number of techniques and design choices to provide solutions to lower the implementation cost of the device compared to traditional airflow meters. The design choices that were found to work well are the single sided transducer arrangement for a “V” shaped reflective path and the use of square wave transmitter pulses ending with the necessary 180° phase changed pulse train to suppress transducer ringing. The device is also designed so that it does not have to rely on high-speed analogue to digital converters (ADC) and intensive digital signal processing, so could be implemented using voltage comparators and low-cost microcontrollers. PMID:25954952

  4. Current status of low-temperature radiator thermophotovoltaic devices

    SciTech Connect

    Charache, G.W.; Egley, J.L.; Danielson, L.R.; DePoy, D.M.; Baldasaro, P.F.; Campbell, B.C. [Lockheed Martin Inc., Schenectady, NY (United States); Hui, S.; Fraas, L.M. [JX-Crystals Inc., Issaquah, WA (United States); Wojtczuk, S.J. [SPIRE Corp., Bedford, MA (United States)

    1996-05-01

    The current performance status of low-temperature radiator (< 1,000 C) thermophotovoltaic (TPV) devices is presented. For low-temperature radiators, both power density and efficiency are equally important in designing an effective TPV system. Comparisons of 1 cm x 1 cm, 0.55 eV InGaAs and InGaAsSb voltaic devices are presented. Currently, InGaAs lattice-mismatched devices offer superior performance in comparison to InGaAsSb lattice-matched devices, due to the former`s long-term development for numerous optoelectronic applications. However, lattice-matched antimony-based quaternaries offer numerous potential advantages.

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

    NASA Technical Reports Server (NTRS)

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

    2012-01-01

    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.

  6. Devices for flow measurement and control -- 1993

    SciTech Connect

    Blechinger, C.J. (ed.) (Ford Motor Co., Dearborn, MI (United States)); Sherif, S.A. (ed.) (Univ. of Florida, Gainesville, FL (United States))

    1993-01-01

    This conference focuses on a small aspect of technological progress, specifically on the devices for flow measurement and control. Papers have been contributed from industry, academia, and government, providing a very broad view of the state of the art and needs for improvement of research. The number of international contributions at this symposium is particularly gratifying to the organizers. There are authors from Great Britain, France, Norway, Germany, and Korea as well as from the US. This implies that flow measurement and control is a topic of significant interest to the international community. It is the editors hope that this symposium volume will serve as a reference for future exchange of ideas and as a catalyst for furthering the state of the art of flow measurement and control. Papers have been processed separately for inclusion on the data base.

  7. Development of device for measurement of electrophysical parameters of biologically active points

    Microsoft Academic Search

    Dmitriy A. Bakulov

    2002-01-01

    Design and electrical schematic diagram are considered for device measuring six parameters of biologically active points (BAP): temperature, ac and dc electrical potential, ac and dc resistance, alternating magnetic field induction. Experiments with prototype show that device provides required accuracy of measurements.

  8. Colloidal-gold electrosensor measuring device

    DOEpatents

    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

    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.

  9. High Temperature Thermoelectric Device Concept Using Large Area PN Junctions

    NASA Astrophysics Data System (ADS)

    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

    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.

  10. Software for keratometry measurements using portable devices

    NASA Astrophysics Data System (ADS)

    Iyomasa, C. M.; Ventura, L.; De Groote, J. J.

    2010-02-01

    In this work we present an image processing software for automatic astigmatism measurements developed for a hand held keratometer. The system projects 36 light spots, from LEDs, displayed in a precise circle at the lachrymal film of the examined cornea. The displacement, the size and deformation of the reflected image of these light spots are analyzed providing the keratometry. The purpose of this research is to develop a software that performs fast and precise calculations in mainstream mobile devices. In another words, a software that can be implemented in portable computer systems, which could be of low cost and easy to handle. This project allows portability for keratometers and is a previous work for a portable corneal topographer.

  11. Ultrasonic device for measuring periodontal attachment levels

    NASA Astrophysics Data System (ADS)

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

    2002-07-01

    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.

  12. Ultimate Diagnostics for the Measurement of Turbulence in Toroidal Devices

    NASA Astrophysics Data System (ADS)

    Park, H.; Mazzucato, E.; Hahm, T. S.; Lee, W. W.; Rewoldt, G.; Synakowski, E.; Domier, C. W.; Luhmann, N. C., Jr.

    1998-11-01

    Relentless efforts in plasma diagnostics concepts (E. Mazzucato, Rev. Sci. Instrum. 69, 1691 (1998), H. Hase, H. Hartfuss,12th HTPD conference, F-16, June 1998.) and technology (R.P. Hsia et al., Rev. Sci. Instrum. 68, 488 (1997).) R&D enable us to design a system capable of simultaneous 3-D imaging of the temperature and density turbulence spectrum in toroidal devices such as tokamak and stellarator. Measurement of multi-dimensional correlation between Te and ne turbulence is extremely important in understanding the current transport model. In this paper, the details of the concept design such as accessibility, machine parameters, detection system and relevant frequencies will be discussed for a various devices. Special attention will be given to obtain ? and k spectra with sufficient spatial resolution so that the results can be readily compared with remarkable visual results produced by gyro-kinetic (GK) and/or gyro-fluid (GF) simulations.

  13. Application of inverse heat conduction problem on temperature measurement

    NASA Astrophysics Data System (ADS)

    Zhang, X.; Zhou, G.; Dong, B.; Li, Q.; Liu, L. Q.

    2013-09-01

    For regenerative cooling devices, such as G-M refrigerator, pulse tube cooler or thermoacoustic cooler, the gas oscillating bring about temperature fluctuations inevitably, which is harmful in many applications requiring high stable temperatures. To find out the oscillating mechanism of the cooling temperature and improve the temperature stability of cooler, the inner temperature of the cold head has to be measured. However, it is difficult to measure the inner oscillating temperature of the cold head directly because the invasive temperature detectors may disturb the oscillating flow. Fortunately, the outer surface temperature of the cold head can be measured accurately by invasive temperature measurement techniques. In this paper, a mathematical model of inverse heat conduction problem is presented to identify the inner surface oscillating temperature of cold head according to the measured temperature of the outer surface in a GM cryocooler. Inverse heat conduction problem will be solved using control volume approach. Outer surface oscillating temperature could be used as input conditions of inverse problem and the inner surface oscillating temperature of cold head can be inversely obtained. A simple uncertainty analysis of the oscillating temperature measurement also will be provided.

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

    NASA Astrophysics Data System (ADS)

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

    2014-10-01

    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.

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

    Microsoft Academic Search

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

    2001-01-01

    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

  16. Noncontact transient temperature mapping of active electronic devices using the thermoreflectance method

    Microsoft Academic Search

    Mihai G. Burzo; Pavel L. Komarov; Peter E. Raad

    2005-01-01

    This work presents a demonstration of the applicability and efficacy of an experimental system capable of noninvasively and nondestructively scanning the transient surface temperature of pulsed microelectronic devices with submicron spatial and sub-microsecond temporal resolutions. The article describes the features of the experimental setup, provides details of the calibration process used to map the changes in the measured surface reflectivity

  17. High temperature skin friction measurement

    NASA Technical Reports Server (NTRS)

    Tcheng, Ping; Holmes, Harlan K.; Supplee, Frank H., Jr.

    1989-01-01

    Skin friction measurement in the NASA Langley hypersonic propulsion facility is described. The sensor configuration utilized an existing balance, modified to provide thermal isolation and an increased standoff distance. For test run times of about 20 sec and ambient-air cooling of the test section and balance, the modified balance performed satisfactorily, even when it was subjected to acoustic and structural vibration. The balance is an inertially balanced closed-loop servo system where the current to a moving-coil motor needed to restore or null the output from the position sensor is a measure of the force or skin friction tending to displace the moving element. The accuracy of the sensor is directly affected by the position sensor in the feedback loop, in this case a linear-variable differential transformer which has proven to be influenced by temperature gradients.

  18. Electrical Devices and Circuits for Low Temperature Space Applications

    NASA Technical Reports Server (NTRS)

    Patterson, R. L.; Hammond, A.; Dickman, J. E.; Gerber, S.; Overton, E.; Elbuluk, M.

    2003-01-01

    The environmental temperature in many NASA missions, such as deep space probes and outer planetary exploration, is significantly below the range for which conventional commercial-off-the-shelf electronics is designed. Presently, spacecraft operating in the cold environment of such deep space missions carry a large number of radioisotope or other heating units in order to maintain the surrounding temperature of the on-board electronics at approximately 20 C. Electronic devices and circuits capable of operation at cryogenic temperatures will not only tolerate the harsh environment of deep space but also will reduce system size and weight by eliminating or reducing the heating units and their associate structures; thereby reducing system development cost as well as launch costs. In addition, power electronic circuits designed for operation at low temperatures are expected to result in more efficient systems than those at room temperature. This improvement results from better behavior in the electrical and thermal properties of some semiconductor and dielectric materials at low temperatures. An on-going research and development program on low temperature electronics at the NASA Glenn Research Center focuses on the development of efficient electrical systems and circuits capable of surviving and exploiting the advantages of low temperature environments. An overview of the program will be presented in this paper. A description of the low temperature test facilities along with selected data obtained from in-house component testing will also be discussed. On-going research activities that are being performed in collaboration with various organizations will also be presented.

  19. Integrated Microfibre Device for Refractive Index and Temperature Sensing

    PubMed Central

    Lim, Kok-Sing; Aryanfar, Iman; Chong, Wu-Yi; Cheong, Yew-Ken; Harun, Sulaiman W.; Ahmad, Harith

    2012-01-01

    A microfibre device integrating a microfibre knot resonator in a Sagnac loop reflector is proposed for refractive index and temperature sensing. The reflective configuration of this optical structure offers the advantages of simple fabrication and ease of sensing. To achieve a balance between responsiveness and robustness, the entire microfibre structure is embedded in low index Teflon, except for the 0.5–2 mm diameter microfibre knot resonator sensing region. The proposed sensor has exhibited a linear spectral response with temperature and refractive index. A small change in free spectral range is observed when the microfibre device experiences a large refractive index change in the surrounding medium. The change is found to be in agreement with calculated results based on dispersion relationships.

  20. Evaluation of Advanced COTS Passive Devices for Extreme Temperature Operation

    NASA Technical Reports Server (NTRS)

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

    2009-01-01

    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.

  1. Assessment of SOI Devices and Circuits at Extreme Temperatures

    NASA Technical Reports Server (NTRS)

    Elbuluk, Malik; Hammoud, Ahmad; Patterson, Richard L.

    2007-01-01

    Electronics designed for use in future NASA space exploration missions are expected to encounter extreme temperatures and wide thermal swings. Such missions include planetary surface exploration, bases, rovers, landers, orbiters, and satellites. Electronics designed for such applications must, therefore, be able to withstand exposure to extreme temperatures and to perform properly for the duration of mission. The Low Temperature Electronics Program at the NASA Glenn Research Center focuses on research and development of electrical devices, circuits, and systems suitable for applications in deep space exploration missions and aerospace environment. Silicon-On-Insulator (SOI) technology has been under active consideration in the electronics industry for many years due to the advantages that it can provide in integrated circuit (IC) chips and computer processors. Faster switching, less power, radiationtolerance, reduced leakage, and high temp-erature capability are some of the benefits that are offered by using SOI-based devices. A few SOI circuits are available commercially. However, there is a noticeable interest in SOI technology for different applications. Very little data, however, exist on the performance of such circuits under cryogenic temperatures. In this work, the performance of SOI integrated circuits, evaluated under low temperature and thermal cycling, are reported. In particular, three examples of SOI circuits that have been tested for operation at low at temperatures are given. These circuits are SOI operational amplifiers, timers and power MOSFET drivers. The investigations were carried out to establish a baseline on the functionality and to determine suitability of these circuits for use in space exploration missions at cryogenic temperatures. The findings are useful to mission planners and circuit designers so that proper selection of electronic parts can be made, and risk assessment can be established for such circuits for use in space missions.

  2. Ergonomic analysis of slip-resistance measurement devices

    Microsoft Academic Search

    ROBERT O. ANDRES; DON B. CHAFFIN

    1985-01-01

    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

  3. Testing and Validation of Phasor Measurement Based Devices

    E-print Network

    Testing 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 Engineering Research Center (PSERC) research project titled "Testing and Validation of Phasor Measurement

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

    PubMed Central

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

    2014-01-01

    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

  5. Networking Low-Power Energy Harvesting Devices: Measurements and Algorithms

    E-print Network

    Shepard, Kenneth

    Networking Low-Power Energy Harvesting Devices: Measurements and Algorithms Maria Gorlatova, Aya--Recent advances in energy harvesting materials and ultra-low-power communications will soon enable the realization of networks composed of energy harvesting devices. These devices will operate using very low ambient energy

  6. Temperature and Strain Coefficient of Velocity for Langasite SAW Devices

    NASA Technical Reports Server (NTRS)

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

    2013-01-01

    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.

  7. 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

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

    PubMed

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

    2014-09-01

    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

  9. Testing limits to airflow perturbation device (APD) measurements

    Microsoft Academic Search

    Erika R. Lopresti; Arthur T. Johnson; Frank C. Koh; William H. Scott; Shaya Jamshidi; Nischom K. Silverman

    2008-01-01

    BACKGROUND: The Airflow Perturbation Device (APD) is a lightweight, portable device that can be used to measure total respiratory resistance as well as inhalation and exhalation resistances. There is a need to determine limits to the accuracy of APD measurements for different conditions likely to occur: leaks around the mouthpiece, use of an oronasal mask, and the addition of resistance

  10. 27 CFR 24.170 - Measuring devices and testing instruments.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...and contents of tanks and other storage containers, and scales and measuring devices for weighing and measuring...5552)) (Approved by the Office of Management and Budget under control number 1512-0298) [T.D....

  11. 27 CFR 24.170 - Measuring devices and testing instruments.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...and contents of tanks and other storage containers, and scales and measuring devices for weighing and measuring...5552)) (Approved by the Office of Management and Budget under control number 1512-0298) [T.D....

  12. Finger temperature controller for non-invasive blood glucose measurement

    NASA Astrophysics Data System (ADS)

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

    2010-11-01

    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.

  13. Stagnation temperature measurement using thin-film platinum resistance sensors

    NASA Astrophysics Data System (ADS)

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

    2014-01-01

    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.

  14. Electrophosphorescence and delayed electroluminescence from pristine polyfluorene thin-film devices at low temperature.

    PubMed

    Sinha, S; Rothe, C; Güntner, R; Scherf, U; Monkman, A P

    2003-03-28

    Intrinsic long-lived electrophosphorescence and delayed electroluminescence from a conjugated polymer (polyfluorene) thin film is observed for the first time at low temperature. From bias offset voltage dependent measurements, it is concluded that the delayed fluorescence is generated via triplet-triplet annihilation. A fast and efficient triplet exciton quenching by charge carriers is found to occur in the active polymer layer of the working devices. PMID:12688898

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

    E-print Network

    Patel, Kanaiyalal Chaturbhai

    1976-01-01

    )or parameters that have been evaluated are reverse leakage current and avalanche breakdown voltage. The Shockley-Read-Hall recombination-generation model is found most suitable to explain the combined influence of temperature and dislocations... PROCEDURE. Device Preparation. Electrical Measurement. Experimental Results. PROBE CORRELATION STUDY. 18 26 Analysis and Discussion. 26 IV ANALYSIS AND DISCUSSION. Reverse Current in Silicon Diode. 37 37 Avalanche Breakdown Voltage. . . 45...

  16. Test device for measuring permeability of a barrier material

    SciTech Connect

    Reese, Matthew; Dameron, Arrelaine; Kempe, Michael

    2014-03-04

    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.

  17. Development of integrated high temperature sensor for simultaneous measurement of wall heat flux and temperature

    NASA Astrophysics Data System (ADS)

    Li, Long; Wang, Jing; Fan, Xuejun

    2012-07-01

    In this paper, an integrated water-cooled sensor has been developed to simultaneously measure the heat flux and temperature at the wall of a scramjet combustor. The upgrade sensor was designed based on the principle of Gardon heat-flux gauge with many improvements. The sensor was well calibrated by both conductive heating sources and blackbody cavity device. The effects of structural material and dimensions on the sensor's responses were examined. Both the experimental measurements and numerical simulation were conducted and showed that the new sensor has the maximum measure ability of heat flux of 400 W/cm2 and stagnation temperatures up to 1920 K along with satisfactory response time.

  18. Axillary and rectal temperature measurements in infants

    Microsoft Academic Search

    C J Morley; P H Hewson; A J Thornton; T J Cole

    1992-01-01

    Rectal and axillary temperatures were measured during the daytime in 281 infants seen randomly at home and 656 at hospital under 6 months old, using mercury-in-glass thermometers. The normal temperature range derived from the babies at home was 36.7-37.9 degrees C for rectal temperature and 35.6-37.2 degrees C for axillary temperature. Rectal temperature was higher than axillary in 98% of

  19. Low Cost Device For Light Flicker Measurement

    Microsoft Academic Search

    Daniele Gallo; Carmine Landi; Nicola Pasquino

    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

  20. Insertion device magnet measurements for the Advanced Light Source

    SciTech Connect

    Marks, S.; Cork, C.; Hoyer, E.; Humphries, D.; Kincaid, B.; Plate, D.; Robb, A.; Schlueter, R.; Wang, C. [Lawrence Berkeley Lab., CA (United States); Hassenzahl, W. [Lawrence Livermore National Lab., CA (United States)

    1993-05-01

    Allowable magnetic field errors for the 4.6 m long insertion devices for the Advanced Light Source (ALS) are extremely small and are driven by electron beam and radiation requirements. Detailed measurements and adjustments of each insertion device are performed to qualify them for installation in the ALS. To accomplish this, a high speed, precision magnetic measurement facility has been designed and built. Hall probe mapping equipment, capable of completing a 2500 sample, 6 m scan with precision axial position monitoring using a laser interferometer in under one minute, is used to obtain both local and integrated field information. A 5.5 m long, 1 cm wide coil is used to measure the field integral through an entire insertion device. This paper describes magnetic measurement equipment, and results of measurements on IDA, the first of the ALS insertion devices.

  1. A Temperature-Monitoring Vaginal Ring for Measuring Adherence

    PubMed Central

    Boyd, Peter; Desjardins, Delphine; Kumar, Sandeep; Fetherston, Susan M.; Le-Grand, Roger; Dereuddre-Bosquet, Nathalie; Helgadóttir, Berglind; Bjarnason, Ásgeir; Narasimhan, Manjula; Malcolm, R. Karl

    2015-01-01

    Background Product adherence is a pivotal issue in the development of effective vaginal microbicides to reduce sexual transmission of HIV. To date, the six Phase III studies of vaginal gel products have relied primarily on self-reporting of adherence. Accurate and reliable methods for monitoring user adherence to microbicide-releasing vaginal rings have yet to be established. Methods A silicone elastomer vaginal ring prototype containing an embedded, miniature temperature logger has been developed and tested in vitro and in cynomolgus macaques for its potential to continuously monitor environmental temperature and accurately determine episodes of ring insertion and removal. Results In vitro studies demonstrated that DST nano-T temperature loggers encapsulated in medical grade silicone elastomer were able to accurately and continuously measure environmental temperature. The devices responded quickly to temperature changes despite being embedded in different thickness of silicone elastomer. Prototype vaginal rings measured higher temperatures compared with a subcutaneously implanted device, showed high sensitivity to diurnal fluctuations in vaginal temperature, and accurately detected periods of ring removal when tested in macaques. Conclusions Vaginal rings containing embedded temperature loggers may be useful in the assessment of product adherence in late-stage clinical trials. PMID:25965956

  2. Measurement of the noise parameters of semiconductor devices

    Microsoft Academic Search

    M. I. Gorlov; D. Yu. Smirnov; D. L. Anufriev

    2006-01-01

    Methods of measuring the fundamental parameters of the low-frequency noise of semiconductor devices are considered and versions\\u000a of instruments for monitoring the noise characteristics of microcircuits, discrete transistors and other semiconductor devices\\u000a are suggested.

  3. Method and apparatus for optical temperature measurements

    DOEpatents

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

    1986-04-22

    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.

  4. Method and apparatus for optical temperature measurement

    DOEpatents

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

    1994-01-01

    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.

  5. Method and apparatus for optical temperature measurement

    DOEpatents

    O'Rourke, P.E.; Livingston, R.R.; Prather, W.S.

    1994-09-20

    A temperature probe and a method for using said probe for temperature measurements based on changes in light absorption by the probe are disclosed. 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 borosilicate glass, accurate to [+-]0.5 C over an operating temperature range of about [minus]196 C to 400 C; and a mixture of D[sub 2]O and H[sub 2]O, accurate to [+-]0.1 C over an operating range of about 5 C to 90 C. 13 figs.

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

    NASA Astrophysics Data System (ADS)

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

    2013-07-01

    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.

  7. A two-thermocouples probe for radiation corrections of measured temperatures in compartment fires

    Microsoft Academic Search

    S Brohez; C Delvosalle; G Marlair

    2004-01-01

    Bare-bead thermocouples are widely used for measuring temperature fields in compartment fires. It is well-known that temperature readings using such a device can be significantly affected by radiation errors, the apparent thermocouple junction temperature being thus different from the true gas temperature. However, a probe consisting of two thermocouples of unequal diameters, but made of the same material can be

  8. Experimental semi-device-independent certification of entangled measurements.

    PubMed

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

    2014-08-22

    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. PMID:25192081

  9. Experimental semi-device-independent certification of entangled measurements

    E-print Network

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

    2014-04-05

    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 measurement statistics only. We also apply our techniques to certify unentangled but nevertheless inherently quantum measurements.

  10. Radiation effects at cryogenic temperatures in Si-JEFT, GaAs MESFET, and MOSFET devices

    SciTech Connect

    Citterio, M.; Rescia, S.; Radeka, V. [Brookhaven National Lab., Upton, NY (United States)] [Brookhaven National Lab., Upton, NY (United States)

    1995-12-01

    Front-end electronics for liquid ionization chamber calorimetry at hadron collider experiments may be exposed to substantial levels of ionizing radiation and neutron fluences in a cryogenic environment. Measurements of devices built with rad-hard technologies have shown that devices able to operate in these conditions exist. Several families of devices (Si-JFET`s, rad-hard MOSFET`s, and GaAs MESFET`s) have been irradiated and tested at a stable cryogenic temperature up to doses of 55 Mrad of ionizing radiation and up to neutron fluences of 4 {times} 10{sup 14} n/cm{sup 2}. Radiation effects on dc characteristics and on noise will be presented.

  11. 29. HAWSER DEVICE, DEVELOPED AT WES FOR MEASURING LONGITUDINAL AND ...

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

    29. HAWSER DEVICE, DEVELOPED AT WES FOR MEASURING LONGITUDINAL AND TRANSVERSE STRESS OF BARGES IN CANAL LOCKS. - Waterways Experiment Station, Hydraulics Laboratory, Halls Ferry Road, 2 miles south of I-20, Vicksburg, Warren County, MS

  12. 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

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

    Microsoft Academic Search

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

    2010-01-01

    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

  14. Temperature measurement through wireless sensor networks

    NASA Astrophysics Data System (ADS)

    Chen, Shuai; Zhong, Xianxin; Chen, Lingling; Liao, Xiaowei

    2006-11-01

    Wireless sensor network is a novel network with a large of nodes through wireless communication for information measurement in distributing area. The temperature measurement through wireless sensor network can get temperature in distributing area without costly infrastructure. In order to realize temperature measurement in wireless communication, the wireless sensor network technology is utilized in the measurement. The wireless sensor node with Atmega128L is introduced. The sensor ERT-J1VR103J is used to induce temperature. The performance of temperature sensor is analyzed. The temperature is gotten by the microprocessor Atmega128L, and then is sent through radio chip CC2420. The wireless sensor network operation system TinyOS is used in the application. The wireless gateway node based on GPRS is utilized in the remote wireless temperature measurement system through Internet network. The user node receives data from gateway to acquire temperature. The experimental result is gotten and the accuracy of temperature is 0.1 Celsius degree with relative accuracy is 0.1 percent. The result indicates that the temperature measurement system through wireless sensor network is reliable, convenient, and low cost.

  15. Accurate temperature measurements with a degrading thermocouple

    SciTech Connect

    Skripnik, Y.A.; Khimicheva, A.I.

    1995-04-01

    Ways are considered of enhancing the accuracy of thermoelectric measurement of temperature. The high accuracy method proposed for monitoring the temperature of an aggressive medium can determine the temperature, irrespective of the instantaneous values of the Seebeck and Peltier coefficients, i.e., irrespective of the uncontrolled thermocouple sensitivity, which varies during use.

  16. Creep measuring device for low melting point metals

    E-print Network

    Portal, Marc-Emmanuel Gilbert

    1987-01-01

    CREEP MEASURING DEVICE FOR LOW MELTING POINT METALS A Thesis MARC-EMMANUEL GILBERT PORTAL Submitted to the Graduate College of Texas AA;M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1987... Major Subject: Nuclear Engineering CREEP MEASURING DEVICE FOR LOW MELTING POINT METALS A Thesis MARC-EMMANUEL GILBERT PORTAL Approved as to style and content by: K. L. Peddicord (Chairman of Committee) C. A. Erdman (Member) F. R. Best (Member...

  17. Experimental device for measuring the momentum of disperse granular materials

    SciTech Connect

    Watling, H.E.; Griffiths, S.K.

    1982-02-10

    An experimental device for measuring the time averaged momentum associated with a steady stream of a disperse granular material has been developed. The mathematical basis for the device is presented including a discussion of using the momentum measurement to compute the local mass or energy fluxes. The analysis considers both nonuniform particle mass and nonuniform velocities for the various constituents of an aggregate material. The results of calibration experiments conducted with a prototype transducer are shown with theoretical predictions of these results.

  18. Temperature measurement systems in wearable electronics

    NASA Astrophysics Data System (ADS)

    Walczak, S.; Go?ebiowski, J.

    2014-08-01

    The aim of this paper is to present the concept of temperature measurement system, adapted to wearable electronics applications. Temperature is one of the most commonly monitored factor in smart textiles, especially in sportswear, medical and rescue products. Depending on the application, measured temperature could be used as an initial value of alert, heating, lifesaving or analysis system. The concept of the temperature measurement multi-point system, which consists of flexible screen-printed resistive sensors, placed on the T-shirt connected with the central unit and the power supply is elaborated in the paper.

  19. LAND LASER:ALTERNATIVE MEASURING DEVICE RECORDS TILLAGE EFFECTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A device is described that enables the amount of above and below ground soil disruption from tillage components to be accurately measured. A laser-based distance measurement system is used to measure tilled soil profiles to determine differences in above and below ground disturbance. Data from an ...

  20. Experiences from measuring human mobility using Bluetooth inquiring devices

    Microsoft Academic Search

    Erik Nordström; Christophe Diot; Richard Gass; Per Gunningberg

    2007-01-01

    We present an analysis of human mobility measurements using Bluetooth devices. A number of data traces from such measurements have been made publicly available for the benefit of the research community. However, the limitations of the measurement approaches are in general not well known. We have been given access to the Intel Motes and to the software that was used

  1. Temperature Dependence of Impact Ionization in Submicrometer Silicon Devices

    Microsoft Academic Search

    D. J. Massey; J. P. R. David; G. J. Rees

    2006-01-01

    Photomultiplication, initiated by both pure electron and pure hole injection, has been measured in submicrometer Si p+-i-n+ and n+-i-p+ diodes with intrinsic region thicknesses w between 0.1 and 0.8 mum, at temperatures between 15 and 420 K. A local analysis is used to extract the values of effective ionization coefficients. Values of bulk ionization coefficients, alpha and beta, are then

  2. The anatomy of a pipe bomb explosion: the effect of explosive filler, container material and ambient temperature on device fragmentation.

    PubMed

    Bors, Dana; Cummins, Josh; Goodpaster, John

    2014-01-01

    Understanding the mechanical properties of different piping material under various conditions is important to predicting the behavior of pipe bombs. In this study, the effect of temperature on pipe bomb containers (i.e., PVC, black steel and galvanized steel) containing low explosive fillers (i.e., Pyrodex and double-base smokeless powder (DBSP)) was investigated. Measurements of fragment velocity and mass were compared for similar devices exploded in the spring (low/high temperature was 8°C/21°C) and winter (low/high temperature range was -9°C/-3°C). The explosions were captured using high speed filmography and fragment velocities were plotted as particle vector velocity maps (PVVM). The time that elapsed between the initiation of the winter devices containing double-base smokeless powder (DBSP) and the failure of their pipe containers ranged from 5.4 to 8.1 ms. The maximum fragment velocities for these devices ranged from 332 to 567 m/s. The steel devices ruptured and exploded more quickly than the PVC device. The steel devices also generated fragments with higher top speeds. Distributions of fragment masses were plotted as histograms and fragment weight distribution maps (FWDM). As expected, steel devices generated fewer, larger fragments than did the PVC devices. Comparison to devices exploded in the spring revealed several pieces of evidence for temperature effects on pipe bombs. For example, the mean fragment velocities for the winter devices were at or above those observed in the spring. The maximum fragment velocity was also higher for the winter steel devices. Although there were no significant differences in mean relative fragment mass, the fragment weight distribution maps (FWDMs) for two winter devices had anomalous slopes, where lower energy filler caused more severe fragmentation than higher energy filler. PMID:24378308

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

    NASA Technical Reports Server (NTRS)

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

    1992-01-01

    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.

  4. Characterization of Permeable Zones by the Measurement of Borehole Temperature

    NASA Astrophysics Data System (ADS)

    Tai, Tung-Lin; Chuang, Po-Yu; Lee, Tsai-Ping; Chia, Yeeping

    2015-04-01

    Subsurface temperature distribution has become an important issue in hydrogeologic studies. The major heat transfer mechanisms in porous medium are conduction and convection. Temperature profile in geological formations with different thermal conductivity would be controlled primarily by heat conduction. The temperature change related to water flows is caused by heat convection. Consequently, temperature profiles are affected by a variety of factors, such as surface temperature change, well diameter, groundwater level change, and water flows inside the borehole. In this study, we use temperature probe as a well logging device to investigate the borehole conditions. There is the depth correction for the time lag problem resulting from the equilibration time of the sensors during the logging process. Then the field measurement was conducted in a 60-m deep well in a gravelly aquifer to characterize the temperature profile of screened zone. In the shallow depth, the change of temperature is primarily influenced by seasonal variation and daily fluctuation. Below the depth of 30-m, the change of temperature was subject to geothermal gradient. However, the slope of temperature profiles changed at approximately 42-m deep, the top of well screen, and it indicated the effects of heat convection in the aquifer. In addition, the measured temperature in the borehole may not represent the actual temperature of aquifer. The measured temperature in the screened section changed continuously in response to pumping, but stabilized an hour data when 2 to 3 times of the borehole water volume is extracted. This phenomenon is related to the temperature mixing with the upper borehole water and aquifer permeability. On the other hand, if the aquifer permeability is high enough, it may influence the temperature profile in borehole through the high flow velocity. The test results indicated that, in order to obtain the actual temperature or chemical constituents, we have to pump 2 to 3 times of the borehole water volume in advance. Another field test was conducted in open holes in the fractured rock formation to characterize the preferential flow area. Detection of the temperature profile anomaly often indicates the lateral water flow inside the open holes due to the forced convection. Compared with results of the other logging devices, we found that temperature logging is possible to locate some relatively permeable fracture zones.

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

    NASA Astrophysics Data System (ADS)

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

    2006-11-01

    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.

  6. 76 FR 11891 - Temperature-Indicating Devices; Thermally Processed Low-Acid Foods Packaged in Hermetically...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-03

    ...indicating devices, in addition to mercury-in-glass thermometers, during processing...canned food processors to transition from mercury-in-glass thermometers to alternative...temperature-indicating devices that do not contain mercury will eliminate concerns about...

  7. Optical Distance Measurement Device And Method Thereof

    SciTech Connect

    Bowers, Mark W. (Patterson, CA)

    2004-06-15

    A system and method of efficiently obtaining distance measurements of a target by scanning the target. An optical beam is provided by a light source and modulated by a frequency source. The modulated optical beam is transmitted to an acousto-optical deflector capable of changing the angle of the optical beam in a predetermined manner to produce an output for scanning the target. In operation, reflected or diffused light from the target may be received by a detector and transmitted to a controller configured to calculate the distance to the target as well as the measurement uncertainty in calculating the distance to the target.

  8. Electron temperature measurements in an argon\\/cesium plasma diode

    Microsoft Academic Search

    Michael J. Ward

    1987-01-01

    Line intensity measurements in an argon\\/cesium plasma diode were made at various locations within the discharge, yielding a spatially resolved electron temperature distribution. This device operated at 0.9 Torr argon, 0.04 Torr cesium, and at a current density of 1.05 mA\\/sq cm. Observations of the spectral line intensities of the 6P greater than nS and 6P greater than nD transitions

  9. Sensorless temperature estimation and control of Peltier devices

    E-print Network

    Odhner, Lael Ulam, 1980-

    2006-01-01

    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 ...

  10. IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 50, NO. 2, FEBRUARY 2003 479 Impact Ionization Measurements

    E-print Network

    Shapira, Yoram

    IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 50, NO. 2, FEBRUARY 2003 479 Impact Ionization Measurements and Modeling for Power PHEMT Tamara Baksht, Student Member, IEEE, Sanelia Solodky, M. Leibovitch in pseudo- morphic high electron mobility transistors (PHEMTs) has been carried out using temperature

  11. Direct in situ measurements of thermospheric temperature

    NASA Technical Reports Server (NTRS)

    Kayser, D. C.; Nier, A. O.; Breig, E. L.; Power, R. A.; Hanson, W. B.

    1979-01-01

    The open source neutral mass spectrometer on the Atmosphere Explorer satellites used for direct in situ measurements of the neutral gas temperature by means of the 'fly-through' mode of operation is evaluated. The derived neutral temperature (Tn) is compared with ion temperatures (T1) obtained simultaneously from the on-board retarding potential analyzer for altitudes and conditions where the two temperatures should be equal. A statistical analysis showed consistency between concurrently observed values of Tn and T1, also shown through profiles depicting their altitude distributions between 150 and 225 km. The overall magnitude of temperatures calculated from the Jacchia (1971) model results in a better representation of the observations than the higher temperatures predicted for this region by the MSIS model (Hedin, 1977), and agreement is also found between observed temperatures and neutral temperatures derived from altitude distributions of N2 particle densities.

  12. Cloud temperature measurement using rotational Raman lidar

    NASA Astrophysics Data System (ADS)

    Su, Jia; Patrick McCormick, M.; Wu, Yonghua; Lee, Robert B.; Lei, Liqiao; Liu, Zhaoyan; Leavor, Kevin R.

    2013-08-01

    Insufficient suppression of the elastic-scattering signal in the rotational Raman (RR) detection channels can result in a retrieval error particularly when the temperature of a thick cloud is measured using an RR lidar. To solve this problem, a technique is presented to obtain relative transmission factors for the two RR channels' thereby correcting for the influence of residual elastic-signal on the temperature retrieval. The feasibility of this technique is demonstrated by applying the algorithm to the Hampton University (HU) lidar measurements. Intercomparisons of these temperature retrievals from both water-phase and cirrus clouds show good agreement with radiosonde measurements.

  13. Emitted vibration measurement device and method

    NASA Technical Reports Server (NTRS)

    Gisler, G. L. (inventor)

    1986-01-01

    This invention is directed to a method and apparatus for measuring emitted vibrational forces produced by a reaction wheel assembly due to imbalances, misalignment, bearing defects and the like. The apparatus includes a low mass carriage supported on a large mass base. The carriage is in the form of an octagonal frame having an opening which is adapted for receiving the reaction wheel assembly supported thereon by means of a mounting ring. The carriage is supported on the base by means of air bearings which support the carriage in a generally frictionless manner when supplied with compressed air from a source. A plurality of carriage brackets and a plurality of base blocks provided for physical coupling of the base and carriage. The sensing axes of the load cells are arranged generally parallel to the base and connected between the base and carriage such that all of the vibrational forces emitted by the reaction wheel assembly are effectively transmitted through the sensing axes of the load cells. In this manner, a highly reliable and accurate measurment of the vibrational forces of the reaction wheel assembly can be had. The output signals from the load cells are subjected to a dynamical analyzer which analyzes and identifies the rotor and spin bearing components which are causing the vibrational forces.

  14. Low emissivity high-temperature tantalum thin film coatings for silicon devices

    SciTech Connect

    Rinnerbauer, Veronika [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Inst. of Soldier Nanotechnologies; Senkevich, Jay J. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Inst. of Soldier Nanotechnologies; Joannopoulos, John D. [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Inst. of Soldier Nanotechnologies; Soljac?ic?, Marin [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Inst. of Soldier Nanotechnologies; Celanovic, Ivan [MIT (Massachusetts Inst. of Technology), Cambridge, MA (United States). Inst. of Soldier Nanotechnologies; Harl, Robert R. [Vanderbilt Univ., Nashville, TN (United States); Rogers, Bridget R. [Vanderbilt Univ., Nashville, TN (United States)

    2013-01-01

    The authors study the use of thin ( ~230 nm ) tantalum (Ta) layers on silicon (Si) as a low emissivity (high reflectivity) coating for high-temperature Si devices. Such coatings are critical to reduce parasitic radiation loss, which is one of the dominant loss mechanisms at high temperatures (above 700 °C ). The key factors to achieve such a coating are low emissivity in the near infrared and superior thermal stability at high operating temperatures. The authors investigated the emissivity of Ta coatings deposited on Si with respect to deposition parameters, and annealing conditions, and temperature. The authors found that after annealing at temperatures ?900 °C the emissivity in the near infrared ( 1–3 ?m ) was reduced by a factor of 2 as compared to bare Si. In addition, the authors measured thermal emission at temperatures from 700 to 1000 °C , which is stable up to a heater temperature equal to the annealing temperature. Furthermore, Auger electron spectroscopy profiles of the coatings before and after annealing were taken to evaluate thermal stability. A thin (about 70 nm) Ta?O? layer was found to act as an efficient diffusion barrier between the Si substrate and the Ta layer to prevent Si diffusion.

  15. Simple Measurement of Quantum Efficiency in Organic Electroluminescent Devices

    Microsoft Academic Search

    Shinji Okamoto; Katsu Tanaka; Yoshitaka Izumi; Hironori Adachi; Takayuki Yamaji; Takeo Suzuki

    2001-01-01

    A simple method of measuring the external quantum efficiency of organic electroluminescent (EL) devices has been investigated. Assuming a perfectly diffusive EL emission surface, this method enables the external quantum efficiency to be calculated from the conventionally measured parameters: luminance, EL spectrum, and current. Its use is limited to EL emission in the visible wavelength range.

  16. ADC's Insertion Devices and Magnetic Measurement Systems Capabilities

    NASA Astrophysics Data System (ADS)

    Deyhim, A.; Kulesza, J.

    2013-03-01

    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.

  17. CMOS-compatible fabrication of room-temperature single-electron devices.

    PubMed

    Ray, Vishva; Subramanian, Ramkumar; Bhadrachalam, Pradeep; Ma, Liang-Chieh; Kim, Choong-Un; Koh, Seong Jin

    2008-10-01

    Devices in which the transport and storage of single electrons are systematically controlled could lead to a new generation of nanoscale devices and sensors. The attractive features of these devices include operation at extremely low power, scalability to the sub-nanometre regime and extremely high charge sensitivity. However, the fabrication of single-electron devices requires nanoscale geometrical control, which has limited their fabrication to small numbers of devices at a time, significantly restricting their implementation in practical devices. Here we report the parallel fabrication of single-electron devices, which results in multiple, individually addressable, single-electron devices that operate at room temperature. This was made possible using CMOS fabrication technology and implementing self-alignment of the source and drain electrodes, which are vertically separated by thin dielectric films. We demonstrate clear Coulomb staircase/blockade and Coulomb oscillations at room temperature and also at low temperatures. PMID:18838999

  18. Dynamic temperature measurements with embedded optical sensors.

    SciTech Connect

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

    2013-10-01

    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.

  19. Ways to measure body temperature in the field.

    PubMed

    Langer, Franz; Fietz, Joanna

    2014-05-01

    Body temperature (Tb) represents one of the key parameters in ecophysiological studies with focus on energy saving strategies. In this study we therefore comparatively evaluated the usefulness of two types of temperature-sensitive passive transponders (LifeChips and IPTT-300) and one data logger (iButton, DS1922L) mounted onto a collar to measure Tb in the field. First we tested the accuracy of all three devices in a water bath with water temperature ranging from 0 to 40°C. Second, we evaluated the usefulness of the LifeChips and the modified iButtons for measuring Tb of small heterothermic mammals under field conditions. For this work we subcutaneously implanted 14 male edible dormice (Glis glis) with transponders, and equipped another 14 males with data loggers to simultaneously record Tb and oxygen consumption with a portable oxygen analyzer (Oxbox). In one individual we recorded Tb with both devices and analyzed recorded Tb patterns. LifeChips are able to measure temperature within the smallest range from 25 to 40°C with an accuracy of 0.07±0.12°C. IPTT-300 transponders measured temperature between 10 and 40°C, but accuracy decreased considerably at values below 30°C, with maximal deviations of nearly 7°C. An individual calibration of each transponder is therefore needed, before using it at low Tbs. The accuracy of the data logger was comparatively good (0.12±0.25°C) and stable over the whole temperature range tested (0-40°C). In all three devices, the repeatability of measurements was high. LifeChip transponders as well as modified iButtons measured Tb reliably under field conditions. Simultaneous Tb-recordings in one edible dormouse with an implanted LifeChip and a collar-mounted iButton revealed that values of both measurements were closely correlated. Taken together, we conclude that implanted temperature-sensitive transponders represent an appropriate and largely non-invasive method to measure Tb also under field conditions. PMID:24802148

  20. Comparison Measurements of Silicon Carbide Temperature Monitors

    Microsoft Academic Search

    Joy L. Rempe; Keith G. Condie; Darrell L. Knudson; Lance Lewis Snead

    2010-01-01

    As part of a process initiated through the Advanced Test Reactor (ATR) National Scientific User Facility (NSUF) program to make Silicon Carbide (SiC) temperature monitors available for experiments, 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.

  1. High-accuracy direct ZT and intrinsic properties measurement of thermoelectric couple devices.

    PubMed

    Kraemer, D; Chen, G

    2014-04-01

    Advances in thermoelectric materials in recent years have led to significant improvements in thermoelectric device performance and thus, give rise to many new potential applications. In order to optimize a thermoelectric device for specific applications and to accurately predict its performance ideally the material's figure of merit ZT as well as the individual intrinsic properties (Seebeck coefficient, electrical resistivity, and thermal conductivity) should be known with high accuracy. For that matter, we developed two experimental methods in which the first directly obtains the ZT and the second directly measures the individual intrinsic leg properties of the same p/n-type thermoelectric couple device. This has the advantage that all material properties are measured in the same sample direction after the thermoelectric legs have been mounted in the final device. Therefore, possible effects from crystal anisotropy and from the device fabrication process are accounted for. The Seebeck coefficients, electrical resistivities, and thermal conductivities are measured with differential methods to minimize measurement uncertainties to below 3%. The thermoelectric couple ZT is directly measured with a differential Harman method which is in excellent agreement with the calculated ZT from the individual leg properties. The errors in both the directly measured and calculated thermoelectric couple ZT are below 5% which is significantly lower than typical uncertainties using commercial methods. Thus, the developed technique is ideal for characterizing assembled couple devices and individual thermoelectric materials and enables accurate device optimization and performance predictions. We demonstrate the methods by measuring a p/n-type thermoelectric couple device assembled from commercial bulk thermoelectric Bi2Te3 elements in the temperature range of 30?°C-150?°C and discuss the performance of the couple thermoelectric generator in terms of its efficiency and materials' self-compatibility. PMID:24784659

  2. Performance measurements of multilayer insulation at variable cold temperature

    NASA Astrophysics Data System (ADS)

    Funke, Thomas; Haberstroh, Christoph

    2012-06-01

    Multilayer insulation (MLI) is commonly used in most cryogenic devices such as LHe-cryostats or superconductive cables. Typically thermal performance measurements have been carried out using bath cryostats. Inherent to all this devices is a fixed cold temperature at the boiling point of the particular cryogenic liquid. A recent approach for cryogenic pressure vessels covers a broad temperature range, i.e. hydrogen storage from 20 K to ambient temperature. Thus, a new calorimeter cryostat has been designed at TU Dresden to meet these requirements. The design as a flow cryostat allows the measurement of the thermal performance with variable cold temperature between 20 K and 300 K. It can be operated in vertical as well as in horizontal orientation. The insulation material is wrapped around a nearly isothermal cylinder which is held at the desired temperature by a cooling fluid. Preferably LHe respectively helium cold gas is used. Several design features reduce undesired interference errors. It is reported about design and equipment of this cryostat plus first experiences in operation

  3. Floating Probe Assembly for Measuring Temperature of Water

    NASA Technical Reports Server (NTRS)

    Stewart, Randy; Ruffin, Clyde

    2002-01-01

    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.

  4. Floating Probe Assembly for Measuring Temperature of Water

    NASA Technical Reports Server (NTRS)

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

    2002-01-01

    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

  5. Development of a magnetic measurement device for thin ribbon samples

    NASA Astrophysics Data System (ADS)

    Sato, Yuta; Todaka, Takashi; Enokizono, Masato

    This paper presents a magnetic measurement device for thin ribbon samples, which are produced by rapid cooling technique. This device enables us to measure magnetic properties easily by only inserting a ribbon sample into a sample holder. The sample holder was made by bakelite to fix any width sample. A long solenoid coil was used to generate a uniform magnetic field and the sample holder was placed at the mid part of the solenoid. The magnetic field strength was measured using a shunt resistor and the magnetic flux density and magnetization in sample ribbons were evaluated by using search coils. The accuracy of measurement was verified with an amorphous metal ribbon sample. Next, we have measured magnetic properties of some magnetic shape memory alloys, which have different compositions. The measured results are compared and we clarified the effect of Sm contents on the magnetic properties.

  6. [Validation of electronic automatic-measurement arterial blood pressure devices].

    PubMed

    de Gaudemaris, R; Asmar, R; Girerd, X; Mallion, J M; Maitre, A

    2000-08-01

    Validation of automatic devices for self blood pressure measurement is a necessity, as the mercury columns are no longer available. The European consensus meeting organized by the Group for blood pressure measurement and evaluation (GEM), from French Society of Hypertension held last June 1999 has defined a new international protocol for clinical validation of these devices. The main parts of this protocol are the following: the blood pressure is measured at the same arm with two observers simultaneously and then with the automatic device sequentially seven times among 38 patients. The evaluation is interrupted after the 15th patient if the pre-analysis fails defined criteria. Technical supports are available: A CD-rom from French society of HTA for the training and certification of observers, a special kit for the evaluation (2 mercury column's and a double stethoscope) and a specific software for data analysis created by the GEM. PMID:10989741

  7. SHORT COMMUNICATION: Time measurement device with four femtosecond stability

    NASA Astrophysics Data System (ADS)

    Panek, Petr; Prochazka, Ivan; Kodet, Jan

    2010-10-01

    We present the experimental results of extremely precise timing in the sense of time-of-arrival measurements in a local time scale. The timing device designed and constructed in our laboratory is based on a new concept using a surface acoustic wave filter as a time interpolator. Construction of the device is briefly described. The experiments described were focused on evaluating the timing precision and stability. Low-jitter test pulses with a repetition frequency of 763 Hz were generated synchronously to the local time base and their times of arrival were measured. The resulting precision of a single measurement was typically 900 fs RMS, and a timing stability TDEV of 4 fs was achieved for time intervals in the range from 300 s to 2 h. To our knowledge this is the best value reported to date for the stability of a timing device. The experimental results are discussed and possible improvements are proposed.

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

    NASA Technical Reports Server (NTRS)

    Chu, T. L.

    1975-01-01

    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.

  9. Development of a new device to measure local heat exchange by evaporation and convection

    NASA Astrophysics Data System (ADS)

    Kakitsuba, N.; Katsuura, T.

    1992-06-01

    According to the principles of heat and mass transfer, the rate of local heat exchange by convection (C) and local heat loss by evaporation (E) can be estimated if temperature and vapor concentration profiles in the boundary layer are measured. In addition, temperature (Ts) and vapor concentration (rho s) at the surface may be predicted from the measured profiles. On this basis, a new device was developed to measure parabolic profiles by incorporating three relative humidity sensors coupled with thermistors into its probe. It has been evaluated from various tests including human experiments. The results showed that the device, with humidity sensors arranged perpendicular to the surface, could estimate C, E, Ts, and rho s in closer agreement with direct measurements when compared with the conventional gradient method. This confirmed that our method had clear advantages over the conventional gradient method under laminar air flow conditions.

  10. A Microwave Radiometer for Internal Body Temperature Measurement

    NASA Astrophysics Data System (ADS)

    Scheeler, Robert Patterson

    This thesis presents the analysis and design of a microwave radiometer for internal body temperature measurements. There is currently no available method for non-invasive temperature measurement inside the human body. However, knowledge of both relative and absolute temperature variations over time is important to a number of medical applications. The research presented in this thesis details a proof-of-concept near-field microwave radiometer demonstrating relative thermometry of a multi-layer phantom. There are a number of technical challenges addressed in this thesis for radiometric determination of sub-degree temperature variations in the human body. A theoretical approach is developed for determining sensing depth from known complex layered tissues, which is defined as a figure of merit, and is shown to be dependent on frequency, electrical properties of the tissues, and the near-field probe. In order to obtain depth resolution, multiple frequency operation can be used, so multi-frequency probes are designed and demonstrated in this work. The choice of frequencies is determined not only by the tissue material properties, but also by the ever increasing radio interference in the environment. In this work, quiet bands allocated to radio astronomy are investigated. The radiometer and probe need to be compact to be wearable, and several advancements are made towards a fully wearable device: multi-frequency low-profile probes are designed and fabricated on a flexible substrate and the process of on-chip integration is demonstrated by a GaAs MMIC cold noise source for radiometer calibration. The implemented proof-of-concept device consists of two radiometers at 1.4 GHz and 2.7 GHz, designed with commercial inexpensive devices that can enable sufficient sensitivity. The device is tested on a phantom with two water layers whose temperatures are varied in a controlled manner, and focused on the human body temperature range. Measured results are discussed qualitatively as they relate to circadian rhythm monitoring. Finally, the thesis identifies future research that is required to make a practical wearable microwave thermometer for internal body temperature measurements.

  11. MISSE 1 and 2 Tray Temperature Measurements

    NASA Technical Reports Server (NTRS)

    Harvey, Gale A.; Kinard, William H.

    2006-01-01

    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.

  12. Embedded optical gauges for dynamic temperature measurements

    NASA Astrophysics Data System (ADS)

    Dolan, Daniel; Ao, Tom

    2011-06-01

    While mechanical diagnostics are common in dynamic compression research, accurate temperature measurements remain elusive. The problem is particularly acute in ramp- compression experiments, where temperatures are often well below 1000 K, a challenging domain for optical pyrometry. Embedded electrical gauges can be used to measure temperature in limited circumstances, but are difficult to incorporate into metal samples or magnetically-driven experiments. Embedded optical gauges may provide a viable temperature diagnostic when pyrometry and electrical gauges are impractical. Unlike pyrometry, where each sample has a unique emissivity, embedded optical gauges reference temperature to the optical properties of a standard material. Active optical measurements also provide direct control over the measured light levels, whereas pyrometry is limited by sample emission in particular spectral regions. This presentation will discuss the use of noble metal reflectivity gauges for dynamic temperature measurements. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85

  13. NaOH-based high temperature heat-of-fusion thermal energy storage device

    NASA Technical Reports Server (NTRS)

    Cohen, B. M.; Rice, R. E.

    1978-01-01

    A material called Thermkeep, developed as a low-cost method for the storage of thermal energy for solar electric power generating systems is discussed. The storage device consists of an insulated cylinder containing Thermkeep in which coiled tubular heat exchangers are immersed. A one-tenth scale model of the design contains 25 heat-exchanger tubes and 1500 kg of Thermkeep. Its instrumentation includes thermocouples to measure internal Thermkeep temperatures, vessel surface, heated shroud surface, and pressure gauges to indicate heat-exchanger pressure drops. The test-circuit design is presented and experimental results are discussed.

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

    E-print Network

    Wang, Wei Hua

    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

  15. Whistle Gauge Measures Flow And Temperature

    NASA Technical Reports Server (NTRS)

    Shakkottai, Parthasarathy; Kwack, Eug Y.

    1989-01-01

    Simple, rugged gauge used to measure speed of flow and temperature of steam or other gas flowing through pipes of arbitrary diameter, from 1 to 28 in. or larger. Specially designed, instrumented whistle - has no moving parts, small, nonobstruction, operates at high temperature and pressure, and cleans itself. Does not operate at zero flow, but at moderate flows (tens of meters per second) generates intense sound for use in measurements. Consists of slanted ring groove of depth D and pressure taps in wall of pipe carrying flow to be measured. Resonant wavelength of sound generated by ring groove depends primarily on size and shape of groove and approximately equal to 4D.

  16. Surface temperature measurement of plasma facing components with active pyrometry

    NASA Astrophysics Data System (ADS)

    Amiel, S.; Loarer, T.; Pocheau, C.; Roche, H.; Aumeunier, M. H.; Gauthier, E.; Le Niliot, C.; Rigollet, F.

    2012-11-01

    In fusion devices like ITER, plasma facing components will be in metal, (Tungsten and Beryllium), with emissivity in the range of 0.1-0.4. Therefore, surface temperature monitoring by infrared system will become more challenging due to low emissivity and consequently non negligible reflected flux. The active pyrometry method proposed in this paper allows surface temperature measurements independently of reflected and parasitic fluxes. A local increase of the surface temperature (?T(t)~10 °C) introduced by a transient heating source (pulsed or modulated) results in an additional component of the flux collected by the detector. A filtering of the signal allows extracting a temporal flux proportional only to the variation of the emitted flux. The ratio of simultaneous measurements at two wavelengths allows solving the unknown emissivity (same as for classical bicolour pyrometry). In this paper, it is described how the active pyrometry method is adapted to the surface temperature measurements of metallic PFCs independently of the reflected fluxes. Experimental results for carbon and tungsten samples are reported. Finally, it is shown how, by using the active pyrometry, the overall 2D standard IR perturbed by a reflected flux is corrected to recover the full 2D surface temperature close to the real surface temperature.

  17. Temperature dependences of electroluminescent characteristics in the devices fabricated with novel triphenylamine derivatives

    Microsoft Academic Search

    Shizuo Tokito; Hiromitsu Tanaka; Koji Noda; Akane Okada; Yasunori Taga

    1997-01-01

    In this paper, we investigated the temperature dependences of the electroluminescent (EL) characteristics of two-layer devices fabricated using four hole-transporting materials based on triphenylamine, and a typical emitting material, tris (8-quinolinolato) aluminum. The thermal stability of the organic EL devices is clearly seen to depend on the glass transition temperature (Tg) of the hole-transporting material. The EL device with a

  18. Analyzing the dynamics of brain circuits with temperature: design and implementation of a miniature thermoelectric device.

    PubMed

    Aronov, Dmitriy; Fee, Michale S

    2011-04-15

    Traditional lesion or inactivation methods are useful for determining if a given brain area is involved in the generation of a behavior, but not for determining if circuit dynamics in that area control the timing of the behavior. In contrast, localized mild cooling or heating of a brain area alters the speed of neuronal and circuit dynamics and can reveal the role of that area in the control of timing. It has been shown that miniaturized solid-state heat pumps based on the Peltier effect can be useful for analyzing brain dynamics in small freely behaving animals (Long and Fee, 2008). Here we present a theoretical analysis of these devices and a procedure for optimizing their design. We describe the construction and implementation of one device for cooling surface brain areas, such as cortex, and another device for cooling deep brain regions. We also present measurements of the magnitude and localization of the brain temperature changes produced by these two devices. PMID:21291909

  19. A survey of gas-side fouling measuring devices

    NASA Astrophysics Data System (ADS)

    Marner, W. J.; Henslee, S. P.

    1984-03-01

    A survey of measuring devices or probes, which were used to investigate gas side fouling, was carried out. Five different types of measuring devices are identified and discussed including: heat flux meters, mass accumulation probes, optical devices, deposition probes, and acid condensation probes. A total of 32 different probes are described in detail and summarized in matrix or tabular form. The important considerations of combustion gas characterization and deposit analysis are also given a significant amount of attention. The results show that considerable work was done in the development of gas side fouling probes. However, it is clear that the design, construction, and testing of a durable, versatile probe - capable of monitoring on-line fouling resistances - remains a formidable task.

  20. Low-temperature thermoelectric refrigerating device using current-carrying superconducting mode\\/nonsuperconducting mode junctions

    Microsoft Academic Search

    Skertic

    1991-01-01

    This patent describes a refrigerating device that produces cooling below a preselected temperature. It comprises: a heat sink operable to produce the preselected temperature; a refrigerating unit, including a first piece of a first material that is electrically conducting but not superconducting at the preselected temperature, a second piece of a second material that is superconducting at the preselected temperature,

  1. Measurement of carrier generation lifetime in SOI devices Hyungcheol Shina,

    E-print Network

    Schroder, Dieter K.

    presents a new, simple method of measuring the generation lifetime in SOI (silicon-on-insulator) MOSFETS this technique, generation lifetime was mapped across ®nished SIMOX (separation by implantated oxygen) wafers to the ¯oating-body nature of the device (Fig. 2) [7±10]. The drain current is suppressed immediately after

  2. Device for Measuring the Acidity of Airborne Contaminants

    E-print Network

    Slatton, Clint

    Device for Measuring the Acidity of Airborne Contaminants The University of Florida is seeking the acidity of airborne materials. This technology uses an innovative technique of colorimetry to respond to the change in acidity of filter samples. Unlike existing products, there is no need for the traditional

  3. Blood damage measures for ventricular assist device modeling

    E-print Network

    Natelson, Douglas

    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

  4. Laser weld penetration estimation using temperature measurements

    SciTech Connect

    Lankalapalli, K.N.; Tu, J.F. [Purdue Univ., West Lafayette, IN (United States). School of Industrial Engineering; Leong, K.H. [Argonne National Lab., IL (United States); Gartner, M. [Ford Motor Co., Livonia, MI (United States)

    1997-10-01

    Penetration depth is an important factor critical to the quality of a laser weld. This paper examines the feasibility of using temperature measurements on the bottom surface of the work-piece to estimate weld penetration. A three-dimensional analytical model relating penetration depth, weld bead width and welding speed to temperature distribution at the bottom surface of the workpiece is developed. Temperatures on the bottom surface of the workpiece are measured using infrared thermocouples located behind the laser beam. Experimental results from bead-on-plate welds on low carbon steel plates of varying thickness at different levels of laser power and speeds validate the model and show that the temperature on the bottom surface is a sensitive indicator of penetration depth. The proposed model is computationally efficient and is suitable for on-line process monitoring application.

  5. Calibration of Automated Non Invasive Blood Pressure Measurement Devices

    Microsoft Academic Search

    E. Balestrieri; S. Rapuano

    Starting from a brief history of blood pressure measurement, the chapter provides a critical overview of the existing standards\\u000a and protocols dealing with the calibration of automated non-invasive measurement of blood pressure. Some issues about the\\u000a device specifications and the test methods, including the most used clinical protocols are pointed out. The lack of a clear\\u000a and unique set of

  6. Methods for measuring acoustic power of an ultrasonic neurosurgical device.

    PubMed

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

    2011-01-01

    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

  7. Temperature measurements of shock-compressed deuterium

    SciTech Connect

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

    1994-11-01

    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.

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

    NASA Astrophysics Data System (ADS)

    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

    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.

  9. Development of integrated high temperature sensor for simultaneous measurement of wall heat flux and temperature.

    PubMed

    Li, Long; Wang, Jing; Fan, Xuejun

    2012-07-01

    In this paper, an integrated water-cooled sensor has been developed to simultaneously measure the heat flux and temperature at the wall of a scramjet combustor. The upgrade sensor was designed based on the principle of Gardon heat-flux gauge with many improvements. The sensor was well calibrated by both conductive heating sources and blackbody cavity device. The effects of structural material and dimensions on the sensor's responses were examined. Both the experimental measurements and numerical simulation were conducted and showed that the new sensor has the maximum measure ability of heat flux of 400 W/cm(2) and stagnation temperatures up to 1920 K along with satisfactory response time. PMID:22852712

  10. Dual neutron flux/temperature measurement sensor

    DOEpatents

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

    1994-10-04

    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.

  11. Dual neutron flux/temperature measurement sensor

    DOEpatents

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

    1994-01-01

    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.

  12. A Method of Measuring Piston Temperatures

    NASA Technical Reports Server (NTRS)

    Pinkel, Benjamin; Mangniello, Eugene J

    1940-01-01

    A method that makes use of thermocouples has been developed to measure the temperature of engine pistons operating at high speeds. The thermocouples installed on the moving piston are connected with a potentiometer outside the engine by means of pneumatically operated plungers, which make contact with the piston thermocouples for about 10 crankshaft degrees at the bottom of the piston stroke. The equipment is operated satisfactory at engine speeds of 2,400 r.p.m. and shows promise of successful operation at higher engine speeds. Measurements of piston temperatures in a liquid-cooled compression-ignition engine and in an air-cooled spark-ignition are presented.

  13. Visible radiation measurement for temperature determination

    NASA Astrophysics Data System (ADS)

    Elands, P. J. M.; Wijchers, T.

    1985-11-01

    The theory of radiation according to the laws of Planck and Stefan-Boltzmann is treated, and the detection of radiation and the detection geometrics are discussed. A detector consisting of a camera, a diode, and an amplifier, was examined to determine geometrics, including lens openings, focal distance, and principal planes. Saturation and the error in adjustment were determined. The procedure of detector calibration by means of a tungsten ribbon lamp is described. Measurements with the equipment to check the calibration constant were carried out on a piece of iron with known temperature. There is fairly good agreement between the results of this pyrometer method and temperature measurements with a thermocouple.

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

    SciTech Connect

    Seong W. Lee

    2004-04-01

    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.

  15. Local bipolar-transistor gain measurement for VLSI devices

    NASA Astrophysics Data System (ADS)

    Bonnaud, O.; Chante, J. P.

    1981-08-01

    A method is proposed for measuring the gain of a bipolar transistor region as small as possible. The measurement then allows the evaluation particularly of the effect of the emitter-base junction edge and the technology-process influence of VLSI-technology devices. The technique consists in the generation of charge carriers in the transistor base layer by a focused laser beam in order to bias the device in as small a region as possible. To reduce the size of the conducting area, a transversal reverse base current is forced through the base layer resistance in order to pinch in the emitter current in the illuminated region. Transistor gain is deduced from small signal measurements. A model associated with this technique is developed, and this is in agreement with the first experimental results.

  16. EFFECTIVE ULTRAVIOLET IRRADIANCE MEASUREMENTS FROM ARTIFICIAL TANNING DEVICES IN GREECE.

    PubMed

    Petri, Aspasia; Karabetsos, Efthymios

    2014-12-01

    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

  17. High Accuracy Temperature Measurements Using RTDs with Current Loop Conditioning

    NASA Technical Reports Server (NTRS)

    Hill, Gerald M.

    1997-01-01

    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.

  18. Recommendations for blood pressure measuring devices for office/clinic use in low resource settings.

    PubMed

    Parati, Gianfranco; Mendis, Shanthi; Abegunde, Dele; Asmar, Ronald; Mieke, Stephan; Murray, Alan; Shengelia, Bakuti; Steenvoorden, Gijs; Van Montfrans, Gert; O'Brien, Eoin

    2005-02-01

    This paper, which summarizes the conclusions of a WHO Expert meeting, is aimed at proposing indications to develop technical specifications for an accurate and affordable blood pressure measuring device for office/clinic use in low resource settings. Blood pressure measuring devices to be used in low resource settings should be accurate, affordable, and easily available worldwide. Given the serious inherent inaccuracy of the auscultatory technique, validated and affordable electronic devices, that have the option to select manual readings, seem to be a suitable solution for low resource settings. The agreement on the technical specifications for automated blood pressure measuring devices for office/clinic use in low resource settings included the following features: high accuracy, adoption of electronic transducers and solar batteries for power supply, standard rates of cuff inflation and deflation, adequate cuff size, digital display powered by solar batteries, facilities for adequate calibration, environmental requirements, no need of memory function, resistance to shock and temperature changes, and low cost. Availability of a device with these features should be accompanied by adequate training of health care personnel, who should guarantee implementation of the procedures recommended in recent European and American Guidelines for accurate blood pressure measurement. PMID:15687867

  19. Note: Zeeman splitting measurements in a high-temperature plasma.

    PubMed

    Golingo, R P; Shumlak, U; Den Hartog, D J

    2010-12-01

    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. PMID:21198059

  20. Note: Zeeman splitting measurements in a high-temperature plasma

    SciTech Connect

    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

    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.

  1. Microwave electrothermal thruster chamber temperature measurements and energy exchange calculations

    NASA Astrophysics Data System (ADS)

    Chianese, Silvio G.

    2005-11-01

    The microwave electrothermal thruster (MET) uses microwave frequency energy to create and sustain a resonant cavity plasma to heat a propellant. It has been operated at a variety of power levels with several propellants. The performance potential of the device has not previously been ascertained because of complex physics involved in the microwave heating, the relatively low thrust of the device, and difficulty in using conventional diagnostics to study molecular plasmas. The objectives of this investigation were to measure heavy particle temperatures and to understand gas heating processes in the MET plasma chamber for representative molecular propellants, oxygen and nitrogen. These molecules have well known thermochemical and structural properties, and they are components of liquid-storable propellants. A 2.45 GHz aluminum cylindrical thruster with converging copper alloy nozzles was used. A spectroscopic system was used to collect light emitted through a window in the plasma chamber. A Schumann-Runge emission model was developed assuming anharmonically vibrating, non-rigid rotating oxygen molecules. The commercially available LIFBASE software was used to model ionized molecular nitrogen first negative system emission from nitrogen plasmas. Experimental data were compared to models using least squared difference summation schemes. Steady and repeatable plasmas were formed with oxygen, nitrogen, and ammonia for most operating conditions. Strong coupling between fluid dynamics and plasma geometry was observed for high flow rate nitrogen tests. Oxygen temperatures of 2,000 K were measured with no variation due to spatial location or pressure and a slight increase in temperature with specific absorbed power. Nitrogen temperatures of 5,500 K were measured with no variation due to location, pressure, or specific absorbed power. Thermochemical calculations show the relationship between equilibrium enthalpy addition, temperature, dissociation fraction, and specific impulse. Nitrogen was found to be an excellent choice as a propellant component while oxygen was found to be a poor choice.

  2. Neutral thermospheric temperature from ion concentration measurements

    NASA Technical Reports Server (NTRS)

    Breig, E. L.; Donaldson, J. S.; Hanson, W. B.; Hoffman, J. H.; Power, R. A.; Kayser, D. C.; Spencer, N. W.; Wharton, L. E.

    1981-01-01

    A technique for extracting information on neutral temperature from in situ F region measurements of O(+) and H(+) ion concentrations is analyzed and evaluated. Advantage is taken of the condition of charge-exchange equilibrium of these species in the neighborhood of 320 km to infer the associated relative abundances of neutral oxygen and hydrogen. Results are shown to be generally consistent with other concurrent in situ measurements.

  3. Calibrating X-ray Imaging Devices for Accurate Intensity Measurement

    SciTech Connect

    Haugh, M. J.

    2011-07-28

    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.

  4. Integrated seal for high-temperature electrochemical device

    SciTech Connect

    Tucker, Michael C; Jacobson, Craig P

    2013-07-16

    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.

  5. Post-Shock Temperature Measurements of Aluminum

    SciTech Connect

    Seifter, A.; Furlanetto, M. R.; Payton, J. R.; Obst, A. W. [University of California, Los Alamos National Laboratory, Physics Division, P-23, Los Alamos, NM 87545 (United States); Stewart, S. T.; Kennedy, G. B. [Department of Earth and Planetary Sciences, Harvard University, 20 Oxford Street, Cambridge MA 02138 (United Kingdom)

    2006-07-28

    Post-shock temperature is an important quantity in shock physics experiments for constraining the dynamic equations of state of materials. A high-speed, infrared, multi-wavelength pyrometer has been developed at Los Alamos National Laboratory (LANL) for measurements in the temperature range from 400 to 1200 K. With customized front end optics, permitting concurrent VISAR measurements in the same optical path, validation experiments on aluminum have been conducted at the new Shock Compression Laboratory at Harvard University. Under <1 millitorr vacuum, a post-shock temperature of 495 K {+-} 30 K was recorded from a polished free surface of aluminum 2024-T4 subject to a peak shock pressure of 34.8{+-}0.8 GPa, in excellent agreement with the equation of state and previous experiments.

  6. Ultrasonic probes for high temperature immersion measurements

    NASA Astrophysics Data System (ADS)

    Rehman, A.-U.; Jen, C.-K.; Ihara, I.

    2001-03-01

    Ultrasonic probes for high temperature measurements in immersion are presented. These probes consist of piezoelectric transducers and buffer rods, and may be operated in the pulse echo mode. The probes can operate to temperatures as high as 215 °C without requiring a cooling system. For imaging purposes, one end of the clad buffer rod is machined into a semi-spherical concave shape, of which the purpose is to focus the ultrasound. The operating frequency is between 5 and 9 MHz. Ultrasonic images, produced using a mechanical raster scan with the probes fully immersed in silicone oil at elevated temperatures, are presented. The importance of the signal-to-noise ratio in the pulse-echo measurement is discussed.

  7. IR temperature measurements in microwave heating

    Microsoft Academic Search

    G. Cuccurullo; P. G. Berardi; R. Carfagna; V. Pierro

    2002-01-01

    In this paper a technique for the evaluation of the dielectric constant of a sample placed inside a microwave oven and confined in a cylindrical box is proposed. The box acts as a waveguide so that a simple model for the propagating wave can be assumed. Since traditional techniques for temperature measurements cannot be applied in microwave heating, the IR

  8. NEUTRON FLUX MEASUREMENT AT ELEVATED TEMPERATURES

    Microsoft Academic Search

    Gray

    1960-01-01

    The problems of neutron flux measurements in hightemperature, low-flux ; (zero-energy) reactors are discussed. Because of the low flux, the detectors ; must operate closer to the core than in power reactors and hence must withstand ; higher temperatures for long periods of time. Gas ionization detectors are ; chosen as being the only type practicable under the acove conditions,

  9. Dynamic gas temperature measurement system, volume 1

    NASA Technical Reports Server (NTRS)

    Elmore, D. L.; Robinson, W. W.; Watkins, W. B.

    1983-01-01

    A gas temperature measurement system with compensated frequency response of 1 kHz and capability to operate in the exhaust of a gas turbine engine combustor was developed. A review of available technologies which could attain this objective was done. The most promising method was identified as a two wire thermocouple, with a compensation method based on the responses of the two different diameter thermocouples to the fluctuating gas temperature field. In a detailed design of the probe, transient conduction effects were identified as significant. A compensation scheme was derived to include the effects of gas convection and wire conduction. The two wire thermocouple concept was tested in a laboratory burner exhaust to temperatures of about 3000 F and in a gas turbine engine to combustor exhaust temperatures of about 2400 F. Uncompensated and compensated waveforms and compensation spectra are presented.

  10. Global trends of measured surface air temperature

    NASA Technical Reports Server (NTRS)

    Hansen, James; Lebedeff, Sergej

    1987-01-01

    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.

  11. Temperature dependence of tris(2,2'-bipyridine) ruthenium (II) device characteristics

    Microsoft Academic Search

    Jason D. Slinker; George G. Malliaras; Samuel Flores-Torres; Héctor D. Abruña; Withoon Chunwachirasiri; Michael J. Winokur

    2004-01-01

    We have investigated the temperature dependence of the current, radiance, and efficiency from electroluminescent devices based on [Ru(bpy)3]2+(PF6-)2, where bpy is 2,2'-bipyridine. We find that the current increases monotonically with temperature from 200 to 380 K, while the radiance reaches a maximum near room temperature. For temperatures greater than room temperature, an irreversible, current-induced degradation occurs with thermal cycling that

  12. Experimental measurement-device-independent verification of quantum steering

    NASA Astrophysics Data System (ADS)

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

    2015-01-01

    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.

  13. Measuring Rocket Engine Temperatures with Hydrogen Raman Spectroscopy

    NASA Technical Reports Server (NTRS)

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

    2001-01-01

    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.

  14. Ultrasonic measurement device for the characterization of microbiological and biochemical processes in liquid media

    NASA Astrophysics Data System (ADS)

    Elvira, L.; Durán, C.; Sierra, C.; Resa, P.; Montero de Espinosa, F.

    2007-07-01

    A measuring device for the characterization of liquid media based on the propagation of ultrasonic waves is presented. It is a four-channel system especially designed for monitoring microbiological and biochemical processes. The liquid samples are placed in commercial glass bottles which can be sterilized. The bottles have inlet and outlet tubes, which can be used for adding substances or extracting samples during the measuring process without interruption. Magnetic stirring can be used to keep the liquid agitated for homogenization purposes. Thermal control elements assure the temperature stability during the measurement. The liquid characterization is based on the detection of amplitude and time-of-flight changes in the sample under study. The main features, operation and performance of this ultrasonic device are analysed in this work, and some measurements and preliminary results are shown.

  15. SiC device development for high temperature sensor applications

    NASA Technical Reports Server (NTRS)

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

    1992-01-01

    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.

  16. Temperature measurements of shocked silica aerogel foam

    NASA Astrophysics Data System (ADS)

    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

    We present recent results of equation-of-state (EOS) measurements of shocked silica (SiO2) 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.

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

    PubMed

    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

    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

  18. Measurement-Device-Independent Quantum Key Distribution over 200 km

    NASA Astrophysics Data System (ADS)

    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

    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.

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

    E-print Network

    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

    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.

  20. Measuring Thermal Conductivity at LH2 Temperatures

    NASA Technical Reports Server (NTRS)

    Selvidge, Shawn; Watwood, Michael C.

    2004-01-01

    For many years, the National Institute of Standards and Technology (NIST) produced reference materials for materials testing. One such reference material was intended for use with a guarded hot plate apparatus designed to meet the requirements of ASTM C177-97, "Standard Test Method for Steady-State Heat Flux Measurements and Thermal Transmission Properties by Means of the Guarded-Hot-Plate Apparatus." This apparatus can be used to test materials in various gaseous environments from atmospheric pressure to a vacuum. It allows the thermal transmission properties of insulating materials to be measured from just above ambient temperature down to temperatures below liquid hydrogen. However, NIST did not generate data below 77 K temperature for the reference material in question. This paper describes a test method used at NASA's Marshall Space Flight Center (MSFC) to optimize thermal conductivity measurements during the development of thermal protection systems. The test method extends the usability range of this reference material by generating data at temperatures lower than 77 K. Information provided by this test is discussed, as are the capabilities of the MSFC Hydrogen Test Facility, where advanced methods for materials testing are routinely developed and optimized in support of aerospace applications.

  1. High temperature measurement of water vapor absorption

    NASA Technical Reports Server (NTRS)

    Keefer, Dennis; Lewis, J. W. L.; Eskridge, Richard

    1985-01-01

    An investigation was undertaken to measure the absorption coefficient, at a wavelength of 10.6 microns, for mixtures of water vapor and a diluent gas at high temperature and pressure. The experimental concept was to create the desired conditions of temperature and pressure in a laser absorption wave, similar to that which would be created in a laser propulsion system. A simplified numerical model was developed to predict the characteristics of the absorption wave and to estimate the laser intensity threshold for initiation. A non-intrusive method for temperature measurement utilizing optical laser-beam deflection (OLD) and optical spark breakdown produced by an excimer laser, was thoroughly investigated and found suitable for the non-equilibrium conditions expected in the wave. Experiments were performed to verify the temperature measurement technique, to screen possible materials for surface initiation of the laser absorption wave and to attempt to initiate an absorption wave using the 1.5 kW carbon dioxide laser. The OLD technique was proven for air and for argon, but spark breakdown could not be produced in helium. It was not possible to initiate a laser absorption wave in mixtures of water and helium or water and argon using the 1.5 kW laser, a result which was consistent with the model prediction.

  2. Temperature measurement on and inside lamps

    NASA Astrophysics Data System (ADS)

    Wallin, Bo

    1994-03-01

    The use of thermography within the lamp manufacturing industry can improve the quality of many types of lamps ranging from normal incandescent lamps to highly specialized lamps for sports arenas, airports or small lamps for cars. There is a strong demand for more light for the same energy input. Specialized lamps for all possible purposes are developed. But it also forces the lamp manufacturers to utilize the available materials to their extremes. The exact control of the temperatures inside or on the lamp shell has therefore become increasingly necessary as temperatures in lamps can be rather extreme. In plasma lamps for example, the plasma can have a temperature of 6000 C, the bulb around 700 C and the electrodes inside the bulb can have temperatures in excess of 2000 C. Thermographic methods have shown their applicability for a large number of measurement cases. Some of these methods and measurement cases are described. As these applications put very special demands on the measurement equipment, these demands are explained in more detail.

  3. Nanoscale holographic interferometry for strain measurements in electronic devices.

    PubMed

    Hÿtch, Martin; Houdellier, Florent; Hüe, Florian; Snoeck, Etienne

    2008-06-19

    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 and three dimensions. Developing methods of strain measurement at the nanoscale has therefore been an important objective in recent years but has proved elusive in practice: none of the existing techniques combines the necessary spatial resolution, precision and field of view. For example, Raman spectroscopy or X-ray diffraction techniques can map strain at the micrometre scale, whereas transmission electron microscopy allows strain measurement at the nanometre scale but only over small sample areas. Here we present a technique capable of bridging this gap and measuring strain to high precision, with nanometre spatial resolution and for micrometre fields of view. Our method combines the advantages of moiré techniques with the flexibility of off-axis electron holography and is also applicable to relatively thick samples, thus reducing the influence of thin-film relaxation effects. PMID:18563161

  4. 49 CFR 179.103-3 - Venting, loading and unloading valves, measuring and sampling devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...false Venting, loading and unloading valves, measuring and sampling devices...103-3 Venting, loading and unloading valves, measuring and sampling devices. (a) Venting, loading and unloading valves, measuring and sampling...

  5. 49 CFR 179.103-3 - Venting, loading and unloading valves, measuring and sampling devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...false Venting, loading and unloading valves, measuring and sampling devices...103-3 Venting, loading and unloading valves, measuring and sampling devices. (a) Venting, loading and unloading valves, measuring and sampling...

  6. 49 CFR 179.103-3 - Venting, loading and unloading valves, measuring and sampling devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...false Venting, loading and unloading valves, measuring and sampling devices...103-3 Venting, loading and unloading valves, measuring and sampling devices. (a) Venting, loading and unloading valves, measuring and sampling...

  7. 49 CFR 179.103-3 - Venting, loading and unloading valves, measuring and sampling devices.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...false Venting, loading and unloading valves, measuring and sampling devices...103-3 Venting, loading and unloading valves, measuring and sampling devices. (a) Venting, loading and unloading valves, measuring and sampling...

  8. 49 CFR 179.103-3 - Venting, loading and unloading valves, measuring and sampling devices.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...false Venting, loading and unloading valves, measuring and sampling devices...103-3 Venting, loading and unloading valves, measuring and sampling devices. (a) Venting, loading and unloading valves, measuring and sampling...

  9. Permeameter for high-temperature magnetic measurements

    NASA Technical Reports Server (NTRS)

    Barranger, J. P.

    1972-01-01

    A permeameter is described that measures the magnetizing force and the corresponding magnetic induction up to 1000 C. The two symmetrical yokes are made of an alloy of 9 percent iron, 91 percent cobalt. A coil surrounding the specimen supplies a magnetizing force of up to 100 oersteds. The instrument uses the magnetic potentiometer principle to cancel the effects of the reluctance of the yoke and the joint gaps. Very close agreement was obtained at room temperature when compared to an MH type permeameter. The effect of temperature on the normal induction curves for the yoke material is also presented.

  10. A new method and device for motion accuracy measurement of NC machine tools. Part 2: device error identification and trajectory measurement of general planar motions

    Microsoft Academic Search

    Hua Qiu; Yanbin Li; Yan Li

    2001-01-01

    This paper describes in two parts a new method and device for measuring motion accuracy of NC machine tools. In the first part, the measurement principle and the characteristics of the prototype device have been presented and discussed. In the second part, an efficient and practical approach to identifying the errors of the proposed device after assembly is developed and

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

    ERIC Educational Resources Information Center

    Petzinger, R. A.

    1993-01-01

    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)

  12. InAs quantum well Hall devices for room-temperature detection of magnetic biomolecular labels

    NASA Astrophysics Data System (ADS)

    Mihajlovic, Goran

    2007-03-01

    The integration of micro- and nanoscale magnetics with molecular biology promises novel applications in fundamental studies of molecular interactions as well as in bioanalysis and biomedical functions. The implementation of this concept requires detection of biomolecular labels in the form of superparamagnetic micro/nano beads, ideally with single bead sensitivity. In this talk we will present our work on the development of miniaturized Hall sensors for detection of such beads. The devices, with Hall cross widths of ˜1 ?m and ˜250 nm, were fabricated from InAs/AlSb quantum well semiconductor heterostructures. Their room-temperature characteristics were examined by Hall effect and electronic noise measurements. In the low frequency range, from 20 Hz to 1.6 kHz, devices have the noise-equivalent magnetic moment sensitivities of order 10^6?B/?Hz and 10^5?B/?Hz respectively. The sensitivity of the latter reaches the 10^4?B/?Hz range above ˜ 1 kHz. By using a phase-sensitive measurement technique and micron-sized Hall crosses we achieved detection of a single 1.2 ?m diameter bead with a signal to noise ratio (S/N) of ˜ 33.3 dB, as well as detection of six 250 nm beads with S/N of ˜ 2.3 dB per bead. Our results from the micro-Hall susceptibility measurement on a single microbead can be explained quantitatively as due to the magnetic response of an ensemble of non-interacting magnetic nanoparticles with broad distribution of magnetic moments. The work demonstrates the efficacy of InAs quantum well Hall devices for applications in high sensitivity magnetic biomolecular detection.

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

    NASA Technical Reports Server (NTRS)

    Bullis, W. M. (editor)

    1972-01-01

    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.

  14. Low emissivity high-temperature tantalum thin film coatings for silicon devices

    E-print Network

    Rinnerbauer, Veronika

    The authors study the use of thin ( ? 230?nm) tantalum (Ta) layers on silicon (Si) as a low emissivity (high reflectivity) coating for high-temperature Si devices. Such coatings are critical to reduce parasitic radiation ...

  15. A New Device for Mechanical Testing of Blood Vessels at Cryogenic Temperatures

    E-print Network

    Rabin, Yoed

    modulus of a specimen with no cryoprotectant, at about -140°C (8.6 and 15.5°C below the glass transitionA New Device for Mechanical Testing of Blood Vessels at Cryogenic Temperatures J.L. Jimenez Rios study focuses on the development of a new device for mechanical testing of blood vessels at cryogenic

  16. Temperature Effects of n-MOSFET Devices with Uniaxial Mechanical Strains

    Microsoft Academic Search

    Mei-Na Tsai; T. C. Chang; Po-Tsun Liu; Osbert Cheng; C. T. Huang

    2006-01-01

    2 This study proposes a method for the investigation of the effects of uniaxial stresses, in a temperature-dependent manner, to MOSFET device characteristics, such as mobility, threshold voltage, and on-current. This simple scheme did not require complicated instruments and generated more homogeneous stresses for elucidating the effects of uniaxial me- chanical strains on MOSFET devices. Experimental and Results The NMOS

  17. Uncertainty analysis in measurement for LED junction temperature and thermal resistance

    NASA Astrophysics Data System (ADS)

    Shen, Haiping; Zhou, Xiaoli; Zhang, Wanlu; Liu, Muqing

    2010-08-01

    LEDs are temperature sensitive devices. Many other characteristics of LEDs strongly depend on their thermal characteristics. So accurate measurement for the junction temperature and thermal resistance of LEDs is important. The uncertainty analysis in these measurements, which is important for accurate measurements, is given in this paper. The standard evaluation method for measurement uncertainty in GUM is used. The junction temperature of an LED is measured by indirect measurement for its forward voltage under constant current. The uncertainty components are from the measurement for the initial junction temperature, the steady forward voltage, the initial forward voltage and the calibration of the voltage-temperature coefficient. The thermal resistance is calculated with the measured junction temperature and the thermal power. The uncertainty components are from the measurement for the junction temperature, input current and forward voltage. Analysis results show that the uncertainty of the junction temperature is the most dominant uncertainty contribution in the measurement for the thermal resistance. In the junction temperature measurement, the uncertainty in the calibration of the voltage-temperature coefficient contributes significantly. Thermal equilibrium and good thermal conducting condition should be obtained. These results give a better understanding and practice guide to an accurate measurement for the junction temperature and thermal resistance of LEDs.

  18. TEMPERATURE-MONITORING AND SAFETY-CONTROL DEVICE

    EPA Science Inventory

    A two channel (sensitive) temperature monitor is described, and a parts list and wiring diagram are given. This equipment can be used as a safety shut-off or alarm system, or both. The sensitivity is 0.3C....

  19. Microwave radiometer for subsurface temperature measurement

    NASA Technical Reports Server (NTRS)

    Porter, R. A.; Bechis, K. P.

    1976-01-01

    A UHF radiometer, operating at a frequency of 800 MHz, was modified to provide an integral, three frequency voltage standing wave ratio (VSWR) circuit in the radio frequency (RF) head. The VSWR circuit provides readings of power transmission at the antenna-material interface with an accuracy of plus or minus 5 percent. The power transmission readings are numerically equal to the emissivity of the material under observation. Knowledge of material emissivity is useful in the interpretation of subsurface apparent temperatures obtained on phantom models of biological tissue. The emissivities of phantom models consisting of lean beefsteak were found to lie in the range 0.623 to 0.779, depending on moisture content. Radiometric measurements performed on instrumented phantoms showed that the radiometer was capable of sensing small temperature changes occurring at depths of at least 19 to 30 mm. This is consistent with previously generated data which showed that the radiometer could sense temperatures at a depth of 38 mm.

  20. Modelling the measured local time evolution of strongly nonlinear heat pulses in the Large Helical Device

    NASA Astrophysics Data System (ADS)

    Dendy, R. O.; Chapman, S. C.; Inagaki, S.

    2013-11-01

    In some magnetically confined plasmas, an applied pulse of rapid edge cooling can trigger either a positive or negative excursion in the core electron temperature from its steady state value. We present a new model which captures the time evolution of the transient, non-diffusive local dynamics in the core plasma. We show quantitative agreement between this model and recent spatially localized measurements (Inagaki et al 2010 Plasma Phys. Control. Fusion 52 075002) of the local time-evolving temperature pulse in cold pulse propagation experiments in the Large Helical Device.

  1. Measurement of Thin Film Integrated Passive Devices on SiC through 500 C

    NASA Technical Reports Server (NTRS)

    Schwartz, Zachary D.; Ponchak, George E.; Alterovitz, Samuel A.; Downey, Alan N.; Chevalier, Christine T.

    2004-01-01

    Wireless communication in jet engines and high temperature industrial applications requires FD integrated circuits (RFICs) on wide bandgap semiconductors such as Silicon Carbide (SiC). In this paper, thin-film NiCr resistors, MIM capacitors, and spiral inductors are fabricated on a high purity semi-insulating 4H-SiC substrate. The devices are experimentally characterized through 50 GHz at temperatures of up to 500 C and the equivalent circuits are deembedded from the measured data. It is shown that the NiCr resistors are stable within 10% to 300 C while the capacitors have a value stable within 10% through 500 C.

  2. Improved Refractometer for Measuring Temperatures of Drops

    NASA Technical Reports Server (NTRS)

    Naqwi, Amir A.

    2004-01-01

    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.

  3. Sensitivity analysis of high temperature spectral emissivity measurement method

    NASA Astrophysics Data System (ADS)

    Veselý, Z.; Honnerová, P.; Martan, J.; Honner, M.

    2015-07-01

    Computer model of temperature distribution in the sample in high temperature spectral emissivity measurement method is introduced. Sensitivity analysis is performed using computer model to determine the effect of various measurement method parameters on the sample temperatures. The effects of measured and reference coating thicknesses, measured coating emissivity and sample surface temperature are analyzed. The utilization of temperature difference between reference coating surface and the interface of reference and measured coatings for total emissivity uncertainty of measured coating is demonstrated.

  4. Measurement of protection factor of respiratory protective devices toward nanoparticles.

    PubMed

    Brochot, C; Michielsen, N; Chazelet, S; Thomas, D

    2012-07-01

    The use of nanoparticles in industry has increased spectacularly over the past few years. Additionally, nanoscale particles seem to be the cause of new professional exposure situations. Due to their size, these particles may build up within the respiratory tract and may even reach the nervous system via the nasal passages; for this reason, it is generally recommended to wear respiratory protective devices (RPDs) in situations where collective protection is impossible to implement or inadequate. Here, we present the test bench ETNA designed to study the efficiency of RPDs in the presence of nanoparticles. The results of the efficiency measurement of two RPDs for two positions (sealed and unsealed) on a Sheffield head, for two inhalation configurations (constant flow and cyclic flow), and for two different particle size distributions of NaCl aerosol (one centered on 13 nm and the other on 59 nm) are presented below. The measurements indicate that when the leaks are negligible at the interface mask/head, the efficiency of RPD is greater for nanoparticles. For major leaks, the device's protection factor changes independently of the size of the particles. Furthermore, no trends with respect to the effect of the respiration type (constant-flow and cyclic-flow tests) have been shown on the device's protection factor. PMID:22752098

  5. Thermoreflectance temperature measurement with millimeter wave

    NASA Astrophysics Data System (ADS)

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

    2014-06-01

    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.

  6. Thermoreflectance temperature measurement with millimeter wave

    SciTech Connect

    Pradere, C., E-mail: christophe.pradere@ensam.eu; Caumes, J.-P.; BenKhemis, S.; Palomo, E.; Batsale, J.-C. [I2M (Institut de Mécanique et d’Ingénierie de Bordeaux) UMR CNRS 5295, TREFLE Department, Esplanade des Arts et Métiers, F-33405 Talence Cedex (France); Pernot, G.; Dilhaire, S. [LOMA UMR 5798: CNRS-UB1, 351 Cours de la Libération, 33405 Talence Cedex (France)

    2014-06-15

    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{sup ?3} K{sup ?1} versus 10{sup ?5} K{sup ?1} for the visible domain, is very promising for future thermoreflectance applications.

  7. NMR measurement of bitumen at different temperatures.

    PubMed

    Yang, Zheng; Hirasaki, George J

    2008-06-01

    Heavy oil (bitumen) is characterized by its high viscosity and density, which is a major obstacle to both well logging and recovery. Due to the lost information of T2 relaxation time shorter than echo spacing (TE) and interference of water signal, estimation of heavy oil properties from NMR T2 measurements is usually problematic. In this work, a new method has been developed to overcome the echo spacing restriction of NMR spectrometer during the application to heavy oil (bitumen). A FID measurement supplemented the start of CPMG. Constrained by its initial magnetization (M0) estimated from the FID and assuming log normal distribution for bitumen, the corrected T2 relaxation time of bitumen sample can be obtained from the interpretation of CPMG data. This new method successfully overcomes the TE restriction of the NMR spectrometer and is nearly independent on the TE applied in the measurement. This method was applied to the measurement at elevated temperatures (8-90 degrees C). Due to the significant signal-loss within the dead time of FID, the directly extrapolated M0 of bitumen at relatively lower temperatures (<60 degrees C) was found to be underestimated. However, resulting from the remarkably lowered viscosity, the extrapolated M0 of bitumen at over 60 degrees C can be reasonably assumed to be the real value. In this manner, based on the extrapolation at higher temperatures (> or = 60 degrees C), the M0 value of bitumen at lower temperatures (<60 degrees C) can be corrected by Curie's Law. Consequently, some important petrophysical properties of bitumen, such as hydrogen index (HI), fluid content and viscosity were evaluated by using corrected T2. PMID:18387325

  8. [Parameters of thermoelectric cooling devices in conditions of variable temperatures of the heat-exchange media].

    PubMed

    Efremov, A A; Bratseva, I I

    1985-01-01

    New method for optimized computing thermoelectric coolers is proposed for the case of variable temperatures within heat-transfer media. The operation of the device is analyzed when the temperature of the cooled medium is greater than the temperature of the heated one, i. e. under conditions of the negative temperature difference. The comparative analysis of the computed and experimental data in values of the cooling and electric power demonstrates fully satisfactory results. PMID:3999961

  9. High-temperature superconducting thin-film-based electronic devices

    SciTech Connect

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

    1996-09-01

    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.

  10. Characterization of structural defects in GST based nano-PCM devices through resistance drift measurements

    NASA Astrophysics Data System (ADS)

    Cinar, Ibrahim; Cogulu, Egecan; Gokce, Aisha; Stipe, Barry; Katine, Jordan; Aktas, Gulen; Ozatay, Ozhan

    2015-03-01

    Phase change memory (PCM) is a promising nonvolatile data storage technology with its high signal to noise ratio and superior scalability. Resistance drift in amorphous phase of the phase change material poses a crucial reliability problem, especially in multiple-bit-per cell PCM devices. The resistance of the amorphous phase uncontrollably increases with time after a reset operation which alters the read/write conditions of the device. Structural relaxation (SR) through a defect annihilation process is considered to be the underlying physical mechanism for resistance drift. Here, we report on our measurements of the resistance drift in a phase change memory device with a single layer Ge2Sb2Te5 (GST) material not only in the amorphous state but also in the intermediate resistance state in devices with square top contact geometry which enables us to assess the reliability of multiple-bit per cell PCM memory devices. Through an analysis of electrical measurements as a function of time and temperature for increasing annealing times, we estimate a rate of change in trap density for both amorphous and mixed phases of the GST material after a switching operation. Our study allows engineering the phase change materials and optimizing programing conditions for future PCM applications. TUBITAK under Contract Number 113F385, Bogazici University Research Fund, 12B03M1, and European Union FP7 Marie Curie International Re-integration Grant PCM-256281.

  11. Measurement and modeling of time- and spatial-resolved wafer surface temperature in inductively coupled plasmas

    SciTech Connect

    Hsu, C. C.; Titus, M. J.; Graves, D. B. [Department of Chemical Engineering, University of California at Berkeley, Berkeley, California 94720 (United States)

    2007-05-15

    The transient temperature profile across a commercial wafer temperature sensor device in an inductively coupled Ar plasma is reported. The measured temperatures are compared to model predictions, based on a coupled plasma-wafer model. The radial temperature profile is the result of the radial profile in the ion energy flux. The ion energy flux profile is obtained by combining the Langmuir probe measurement, the ion wall flux probe measurement, and a plasma model. A methodology to estimate the ion flux profile using the sensor measurements has been validated by combining the plasma measurements, the wafer temperature measurements, and the plasma-wafer model. It is shown that with minimal heat transfer between the wafer and the chuck, the initial transient wafer temperature profile after plasma ignition can be used to estimate the ion energy flux profile across the wafer.

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

    PubMed Central

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

    2009-01-01

    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

  13. Optimization of the atmospheric temperature field measurements

    NASA Astrophysics Data System (ADS)

    Rosa, Bogdan J.; Bajer, Konrad; Haman, Krzysztof E.; Szoplik, Tomasz

    2004-11-01

    Small-scale inhomogeneities of the atmospheric temperature field are caused by air turbulence and result in refractive index fluctuations, which in turn influence the propagation of optical beams. Understanding small density fluctuations in the atmosphere is important for the free-space laser communication and for high-resolution imaging through the atmosphere. The ultra-fast aircraft resistance thermometer constructed in the Institute of Geophysics, Warsaw University, measures the temperature of cloudless air and of warm clouds with 10 kHz sampling frequency. During a flight at the speed of 100 m/s, at low altitudes up to 2 km, this corresponds to the spatial resolution of the order of one centimeter. This resolution is sufficient for studying small density fluctuations in the atmospheric boundary layer. A streamlined shield protects the sensing wire of the thermometer from cloud droplets and other small particles suspended in the air but introduce aerodynamic disturbances in the form of vortices. The thermometer records the resulting fluctuations of temperature as noise. The shield sucks air and water collected on its surface through the suction slits. This suction also suppresses the disturbances. In this paper we analyze how the temperature measurements are influenced by: (i) turbulence generated behind the shield placed in front of the sensing wire; (ii) suction of air through the shield slits; (iii) cloud droplets of various space distributions, masses and velocities. We have carried out the 2D numerical simulations of the time-dependent, incompressible, viscous flow (the Navier-Stokes equation) around the shield placed in a uniform stream. We solved the particle path equations for an ensamble of droplets in the Stokes approximation. All the simulations are oriented toward optimization of the shield shape in order to (i) reduce noise in measurements at low and high altitudes and (ii) protect the sensing wire against ice crystals in flights at high altitudes.

  14. Heat insulating device for low temperature liquified gas storage tanks

    Microsoft Academic Search

    T. Okamoto; T. Nishimoto; K. Sawada; K. Hayakawa; T. Kurihara

    1977-01-01

    The insulating construction for a low temperature liquified gas storage tank consists of a plurality of heat insulating blocks or plates of rigid foam, each covered with a gas-tight sheet bonded thereto and each bolted at its approximate center to the outer wall of the tank. The joints between adjacent plates are filled with a heat insulating material and a

  15. HEATRING -SMART INVESTIGATION OF TEMPERATURE IMPACT ON INTEGRATED CIRCUIT DEVICES

    E-print Network

    Paris-Sud XI, Université de

    , Gußhausstraße 27­29, A-1040 Wien, Austria Phone: +43-1-58801/36028, Fax: +43-1-58801/36099, Email: nentchev heatrings is not necessary, since for both heatrings at the designated temperature the results would-doped pro- tection ring RP. These structures are embedded in the sil- icon wafer. Only the metallic supply

  16. Comparison of nickel silicide and aluminium ohmic contact metallizations for low-temperature quantum transport measurements

    PubMed Central

    2011-01-01

    We examine nickel silicide as a viable ohmic contact metallization for low-temperature, low-magnetic-field transport measurements of atomic-scale devices in silicon. In particular, we compare a nickel silicide metallization with aluminium, a common ohmic contact for silicon devices. Nickel silicide can be formed at the low temperatures (<400°C) required for maintaining atomic precision placement in donor-based devices, and it avoids the complications found with aluminium contacts which become superconducting at cryogenic measurement temperatures. Importantly, we show that the use of nickel silicide as an ohmic contact at low temperatures does not affect the thermal equilibration of carriers nor contribute to hysteresis in a magnetic field. PMID:21968083

  17. Modeling of SiC Lateral Resonant Devices Over a Broad Temperature Range

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

    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.

  18. Device accurately measures and records low gas-flow rates

    NASA Technical Reports Server (NTRS)

    Branum, L. W.

    1966-01-01

    Free-floating piston in a vertical column accurately measures and records low gas-flow rates. The system may be calibrated, using an adjustable flow-rate gas supply, a low pressure gage, and a sequence recorder. From the calibration rates, a nomograph may be made for easy reduction. Temperature correction may be added for further accuracy.

  19. PARduino: A Simple Device Measuring and Logging Photosynthetically Active Radiation

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

    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.

  20. Temperature dependent EUV spectra of Gd, Tb and Dy ions observed in the Large Helical Device

    NASA Astrophysics Data System (ADS)

    Suzuki, C.; Koike, F.; Murakami, I.; Tamura, N.; Sudo, S.

    2015-07-01

    We have observed a number of different types of extreme ultraviolet (EUV) spectra from highly charged gadolinium (Gd), terbium (Tb) and dysprosium (Dy) ions in optically thin plasmas produced in the Large Helical Device at the National Institute for Fusion Science. Temporal changes in EUV spectra in the 6–9 nm region subsequent to the injections of solid pellets were measured by a grazing incidence spectrometer. The spectra rapidly change from discrete features into unresolved transition arrays (UTAs) following a drop in the electron temperature after the heating power is reduced. In particular, extremely narrowed UTA features, which comprise spectral lines of Ag-like, Pd-like and neighboring ion stages, are observed when the peak electron temperature is less than 0.45 keV due to the formation of hollow plasmas. Some discrete spectral lines of Cu-like and Ag-like ions have been identified in the high and low temperature plasmas, respectively, some of which are experimentally identified for the first time.

  1. Molecular fluorescence measurements with a charge-coupled device detector

    NASA Astrophysics Data System (ADS)

    Epperson, Patrick M.; Jalkian, Rafi D.; Denton, M. B.

    1988-02-01

    A novel fluorescence spectrometer is described using a two-dimensional charge-coupled device as the detector and a mercury pen lamp as the excitation source. The fluorescence spectra and intensity of anthracene in ethanol standards at concentrations ranging from .0001 to 10 to the minus 11th power M are shown. The limit of detection measured is 10 to the minus 12th power M, or 227 parts-per-quadrillion. The linear dynamic range obtained with this instrument is 6 orders of magnitude with excellent linearity using 10 second signal integration time.

  2. Molecular fluorescence measurements with a charge-coupled device detector

    NASA Astrophysics Data System (ADS)

    Epperson, P. M.; Jalkian, R. D.; Denton, M. B.

    1988-02-01

    A novel fluorescence spectrometer is described using a two-dimensional charge-coupled device as the detector and a mercury pen lamp as the excitation source. The fluorescence spectra and intensity of anthracene in ethanol standards at concentrations ranging from 0.0001 to 10 to the minus 11th power M are shown. The limit of detection measured is 10 to the minus 12th power M, or 227 parts-per-quadrillion. The linear dynamic range obtained with this instrument is 6 orders of magnitude with excellent linearity using 10 second signal integration time.

  3. Method and device for measuring single-shot transient signals

    DOEpatents

    Yin, Yan

    2004-05-18

    Methods, apparatus, and systems, including computer program products, implementing and using techniques for measuring multi-channel single-shot transient signals. A signal acquisition unit receives one or more single-shot pulses from a multi-channel source. An optical-fiber recirculating loop reproduces the one or more received single-shot optical pulses to form a first multi-channel pulse train for circulation in the recirculating loop, and a second multi-channel pulse train for display on a display device. The optical-fiber recirculating loop also optically amplifies the first circulating pulse train to compensate for signal losses and performs optical multi-channel noise filtration.

  4. [Device for measuring paw edema in rats and mice].

    PubMed

    Sibiriak, S V; Afanas'ev, G F; Lazareva, D N; Zarudi?, F S

    1985-01-01

    An unsophisticated highly precise mercuric electron-mechanic oncometer is proposed. It is intended for measuring paw edema in small laboratory animals during screening of new antiphlogistics. The device consists of two communicating vessels. The change in the mercury level after paw immersion transforms to the electrical signal by the induction technique. The controller of the displacement consists of a float, a ferromagnetic rod and a coil with windings. The movement of the rod changes mutual induction of the windings, amplitude modulation of the carrier frequency of the generator and unbalance of the differential diode bridge. The magnitude of the unbalance is recorded with the aid of appropriate units. PMID:4085622

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

    NASA Technical Reports Server (NTRS)

    Bullis, W. M. (editor)

    1971-01-01

    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.

  6. Long-Distance Measurement-Device-Independent Multiparty Quantum Communication

    NASA Astrophysics Data System (ADS)

    Fu, Yao; Yin, Hua-Lei; Chen, Teng-Yun; Chen, Zeng-Bing

    2015-03-01

    The Greenberger-Horne-Zeilinger (GHZ) entanglement, originally introduced to uncover the extreme violation of local realism against quantum mechanics, is an important resource for multiparty quantum communication tasks. But the low intensity and fragility of the GHZ entanglement source in current conditions have made the practical applications of these multiparty tasks an experimental challenge. Here we propose a feasible scheme for practically distributing the postselected GHZ entanglement over a distance of more than 100 km for experimentally accessible parameter regimes. Combining the decoy-state and measurement-device-independent protocols for quantum key distribution, we anticipate that our proposal suggests an important avenue for practical multiparty quantum communication.

  7. Simple uniaxial pressure device for ac-susceptibility measurements suitable for closed cycle refrigerator system.

    PubMed

    Arumugam, S; Manivannan, N; Murugeswari, A

    2007-06-01

    A simple design of the uniaxial pressure device for the measurement of ac-susceptibility at low temperatures using closed cycle refrigerator system is presented for the first time. This device consists of disc micrometer, spring holder attachment, uniaxial pressure cell, and the ac-susceptibility coil wound on stycast bobbin. It can work under pressure till 0.5 GPa and at the temperature range of 30-300 K. The performance of the system at ambient pressure is tested and calibrated with standard paramagnetic salts [Gd(2)O(3), Er(2)O(3), and Fe(NH(4)SO(4))(2)6H(2)O], Fe(3)O(4), Gd metal, Dy metal, superconductor (YBa(2)Cu(3)O(7)), manganite (La(1.85)Ba(0.15)MnO(3)), and spin glass material (Pr(0.8)Sr(0.2)MnO(3)). The performance of the uniaxial pressure device is demonstrated by investigating the uniaxial pressure dependence of La(1.85)Ba(0.15)MnO(3) single crystal with P||c axis. The Curie temperature (T(c)) decreases as a function of pressure with P||c axis (dT(c)dP(||c axis)=-11.65 KGPa) up to 46 MPa. The design is simple, is user friendly, and does not require pressure calibration. Measurement can even be made on thin and small size oriented crystals. The failure of the coil is remote under uniaxial pressure. The present setup can be used as a multipurpose uniaxial pressure device for the measurement of Hall effect and thermoelectric power with a small modification in the pressure cell. PMID:17614625

  8. Infrared radiometric technique in temperature measurement

    NASA Technical Reports Server (NTRS)

    Glazer, S.; Madding, R.

    1988-01-01

    One class of commercially available imaging infrared radiometers using cooled detectors is sensitive to radiation over the 3 to 12 micron wavelength band. Spectral filters can tailor instrument sensitivity to specific regions where the target exhibits optimum radiance. The broadband spectral response coupled with real time two-dimensional imaging and emittance/background temperature corrections make the instruments useful for remote measurement of surface temperatures from -20 C to +1500 C. Commonly used radiometric techniques and assumptions are discussed, and performance specifications for a typical modern commercial instrument are presented. The potential usefulness of an imaging infrared radiometer in space laboratories is highlighted through examples of research, nondestructive evaluation, safety, and routine maintenance applications. Future improvements in instrument design and application of the radiometric technique are discussed.

  9. Using Wireless Power Meters to Measure Energy Use of Miscellaneous and Electronic Devices in Buildings

    E-print Network

    Brown, Richard

    2012-01-01

    a High-Fidelity Wireless Building Energy Auditing Network.Wireless Power Meters to Measure Energy Miscellaneous and Electronic Devices in BuildingsWireless Power Meters to Measure Energy Use of Miscellaneous and Electronic Devices in Buildings

  10. Skin friction measurements in high temperature high speed flows

    NASA Technical Reports Server (NTRS)

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

    1992-01-01

    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.

  11. Sensors for soil profile water content measurement: accuracy, axial response and temperature dependence

    NASA Astrophysics Data System (ADS)

    Evett, S.; Tolk, J.; Howell, T.

    2003-04-01

    We compared sensors for soil water measurement that can be used in access tubes, including the Sentek EnviroSCAN and Diviner 2000 capacitance devices, the Delta-T PR1/6 capacitance probe, the Trime T3 tube-probe, all called electrical devices, and the soil moisture neutron probe (SMNP). Measurements were made before, during and after wetting to saturation in triplicate re-packed columns of three soils: a silty clay loam (30% clay, 53% silt), a clay (48% clay, 39% silt), and a calcic clay loam (35% clay, 40% silt) containing 50% CaCO_3. Each 75-cm deep, 55-cm diameter column was weighed continuously to 50-g precision. Conventional time domain reflectometry (TDR) measurements of water content and thermocouple measurements of temperature were made at several depths in each column. Axial sensitivity of each device was investigated by taking measurements as its probe was lowered from a height well above the soil surface to well below the soil surface. Comparisons of soil water content reported by the devices vs. soil temperature showed that all of the devices were sensitive to temperature except for TDR and the SMNP. The Trime and Delta-T devices were so sensitive to temperature (0.020 and 0.025 m^3 m-3 ^oC-1, respectively, at the wet end) as to be inappropriate for routine field measurements of soil water content. All devices exhibited measurement precision better than 0.01 m^3 m-3. Accuracy of the devices was judged by the root mean squared difference (RMSD) between mass balance column-mean water contents and those determined by the devices using factory calibrations. The Delta-T system was most inaccurate, with an RMSD of 1.30 m^3 m-3 on the wet end. At the saturated end, the Diviner, EnviroSCAN and Trime devices exhibited RMSD values >0.05 m^3 m-3, while the neutron probe and TDR exhibited RMSD <0.03 m^3 m-3. All of the devices would require separate calibrations for soil horizons with widely different properties. Of the electrical devices, only the Delta-T exhibited axial sensitivity larger than the axial height of the sensor, indicating small measurement volumes generally, and suggesting that these systems may be susceptible to soil disturbance close to the access tube during installation.

  12. Development of an ankle torque measurement device for measuring ankle torque during walking

    PubMed Central

    Tanino, Genichi; Tomita, Yutaka; Mizuno, Shiho; Maeda, Hirofumi; Miyasaka, Hiroyuki; Orand, Abbas; Takeda, Kotaro; Sonoda, Shigeru

    2015-01-01

    [Purpose] To develop a device for measuring the torque of an ankle joint during walking in order to quantify the characteristics of spasticity of the ankle and to verify the functionality of the device by testing it on the gait of an able-bodied individual and an equinovarus patient. [Subjects and Methods] An adjustable posterior strut (APS) ankle-foot orthosis (AFO) was used in which two torque sensors were mounted on the aluminum strut for measuring the anterior-posterior (AP) and medial-lateral (ML) directions. Two switches were also mounted at the heel and toe in order to detect the gait phase. An able-bodied individual and a left hemiplegic patient with equinovarus participated. They wore the device and walked on a treadmill to investigate the device’s functionality. [Results] Linear relationships between the torques and the corresponding output of the torque sensors were observed. Upon the analyses of gait of an able-body subject and a hemiplegic patient, we observed toque matrices in both AP and ML directions during the gait of the both subjects. [Conclusion] We developed a device capable of measuring the torque in the AP and ML directions of ankle joints during gait.

  13. Multilayer compressive seal for sealing in high temperature devices

    DOEpatents

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

    2007-08-21

    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.

  14. Ohmic contacts for high-temperature GaP devices 

    E-print Network

    Van der Hoeven, Willem Bernard

    1981-01-01

    REMOVAL 10 13 24 24 26 50 50 52 78 80 83 98 98 99 100 TABLE OF CONTENTS (Continued) APPENDIX D ? 6 LIFT-OFF PREMETAL PREPARATION APPENDIX D ? 7 METAL LIFTOFF Page 100 100 vi LIST OP TABLES Table I Relative High Temperature... of Operation II Summary of Ohmic Contact Materials for GaP III Standard GaP Ohmic Contact Processing Sequence IV Lift-Off GaP Ohmic Contact Process Sequence Page 25 25 Figure l. 7. 8. 10. 12. 13. 14. 15. 16. 17. 18. LIST OF FIGURES I...

  15. Temperature-dependent kink effect model for partially-depleted SOI NMOS devices

    Microsoft Academic Search

    S. C. Lin; J. B. Kuo

    1999-01-01

    This paper reports a closed-form analytical temperature-dependent kink effect model for the partially-depleted SOI NMOS devices. Based on the body-emitter voltage model, an analytical triggering VDS formula for temperature-dependent kink effect has been obtained. According to the analytical model, at a higher operation temperature and with a lighter thin-film doping density, the onset of the kink effect occurs at a

  16. High-rate measurement-device-independent quantum cryptography

    NASA Astrophysics Data System (ADS)

    Pirandola, Stefano; Ottaviani, Carlo; Spedalieri, Gaetana; Weedbrook, Christian; Braunstein, Samuel L.; Lloyd, Seth; Gehring, Tobias; Jacobsen, Christian S.; Andersen, Ulrik L.

    2015-06-01

    Quantum cryptography achieves a formidable task—the remote distribution of secret keys by exploiting the fundamental laws of physics. Quantum cryptography is now headed towards solving the practical problem of constructing scalable and secure quantum networks. A significant step in this direction has been the introduction of measurement-device independence, where the secret key between two parties is established by the measurement of an untrusted relay. Unfortunately, although qubit-implemented protocols can reach long distances, their key rates are typically very low, unsuitable for the demands of a metropolitan network. Here we show, theoretically and experimentally, that a solution can come from the use of continuous-variable systems. We design a coherent-state network protocol able to achieve remarkably high key rates at metropolitan distances, in fact three orders of magnitude higher than those currently achieved. Our protocol could be employed to build high-rate quantum networks where devices securely connect to nearby access points or proxy servers.

  17. Control and Data Analysis for Emittance Measuring Devices

    E-print Network

    Hoffmann, T

    2001-01-01

    Due to the wide range of heavy ion beam intensities and energies in the GSI linac and the associated transfer channel to the synchrotron, several different types of emittance measurement systems have been established. Many common devices such as slit/grid or dipole-sweep systems are integrated into the GSI control system. Other systems like the single shot pepper pot method using CCD-cameras or stand-alone slit/grid set-ups are connected to personal computers. An overview is given about the various systems and their software integration. Main interest is directed on the software development for emittance front-end control and data analysis such as evaluation algorithms or graphical presentation of the results. In addition, special features for improved usability of the software such as data export, project databases and automatic report generation will be presented. An outlook on a unified evaluation procedure for all different types of emittance measurement is given.

  18. Portable measurement, analysis device can calculate GLE/SRE

    SciTech Connect

    Hary, D. [Integrated Scientific Resources, Santa Monica, CA (United States); Miller, M.R. [Precision General, Inc., Houston, TX (United States)

    1995-05-01

    In today`s natural gas market environment it is particularly important for buyers to receive exact flow measurement data. However, it is difficult to receive accurate measurement data because of pulsation problems within the pipe line system. Pulsation, which can be caused by compressors, flow control valves, regulators and some pipe configurations, can alter gas flow measurement. To receive exact measurements, many gas buyers require a pulsation clause, guaranteeing that suppliers maintain a pulsation level in their lines within specifications. To this end, customers often insist that suppliers provide a square root error (SRE) measurement that indicates the amount of pulsation a pipe line experiences and that it is within specified limits. Measuring GLE and SRE errors can be a time consuming, troublesome task. The PGI GLE/SRE tester is a portable measurement and analysis device designed to solve this problem. It can quickly and accurately calculate GLE and SRE and other errors, and stores real-time flow data on disk. This data portability enables engineers to study and analyze the data at a later time. Developed for Precision General by Integrated Scientific Resources, the GLE/SRE tester accurately measures those primary-element and secondary-element errors identified by The Pipeline and Compressor Research Council (PCRC) of the Southern Gas Association (SGA), and the Southwest Research Institute (SWI). The unit includes a Twinhead 486DX/33 laptop computer, a Keithley MetraByte DAS-1200 and DAStation expansion chassis for notebook computers, two Rosemount 3051C differential pressure transmitters, A Validyne P305D differential pressure transducer, and PipePeer software. The laptop compatible has a 33 MHz clock, 200 MBytes of hard drive storage and an LCD display.

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

    SciTech Connect

    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

    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.

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

    NASA Astrophysics Data System (ADS)

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

    2010-10-01

    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.

  1. Application of a ratiometric laser induced fluorescence (LIF) thermometry for micro-scale temperature measurement for natural convection flows 

    E-print Network

    Lee, Heon Ju

    2004-11-15

    A ratiometric laser induced fluorescence (LIF) thermometry applied to micro-scale temperature measurement for natural convection flows. To eliminate incident light non-uniformity and imperfection of recording device, two ...

  2. Application of a ratiometric laser induced fluorescence (LIF) thermometry for micro-scale temperature measurement for natural convection flows

    E-print Network

    Lee, Heon Ju

    2004-11-15

    A ratiometric laser induced fluorescence (LIF) thermometry applied to micro-scale temperature measurement for natural convection flows. To eliminate incident light non-uniformity and imperfection of recording device, two fluorescence dyes are used...

  3. Simultaneous directional bending and temperature measurement with overlapping long period grating and fiber Bragg grating structure

    NASA Astrophysics Data System (ADS)

    Wang, Li; Zhang, Weigang; Geng, Pengcheng; Gao, Shecheng; Li, Jieliang; Bai, Zhiyong; Chen, Lei; Zhang, Shanshan; Liu, Yongji; Yan, Tieyi

    2014-05-01

    A simple and compact device for simultaneous directional bending and temperature sensing is proposed and demonstrated. The device is constructed by overlapping a long period grating (LPG) on a fiber Bragg grating (FBG), and is capable of measuring the directional bending and the temperature at the same position. The LPG written with CO2 laser irradiation has a cross asymmetrical refractive modulation and the FBG is formed by UV laser exposure in the fiber core. The cross-sensitivity between measurement of the directional bending and of the temperature of an LPG is effectively eliminated by solving a matrix equation, by considering the temperature response characteristics of FBG. Experimental results show that the bending and temperature sensitivities are - 6.819 nm m-1 in a range from -2 to 2 m-1 and 10.25 pm °C-1, respectively.

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

    Microsoft Academic Search

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

    1997-01-01

    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.

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

    NASA Technical Reports Server (NTRS)

    Patterson, Richard; Hammoud, Ahmad; Elbuluk, Malik

    2008-01-01

    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.

  6. A device for measuring sonic velocity and compressor Mach number

    NASA Technical Reports Server (NTRS)

    Huber, Paul W; Kantrowitz, Arthur

    1947-01-01

    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.

  7. Development of an ankle torque measurement device for measuring ankle torque during walking.

    PubMed

    Tanino, Genichi; Tomita, Yutaka; Mizuno, Shiho; Maeda, Hirofumi; Miyasaka, Hiroyuki; Orand, Abbas; Takeda, Kotaro; Sonoda, Shigeru

    2015-05-01

    [Purpose] To develop a device for measuring the torque of an ankle joint during walking in order to quantify the characteristics of spasticity of the ankle and to verify the functionality of the device by testing it on the gait of an able-bodied individual and an equinovarus patient. [Subjects and Methods] An adjustable posterior strut (APS) ankle-foot orthosis (AFO) was used in which two torque sensors were mounted on the aluminum strut for measuring the anterior-posterior (AP) and medial-lateral (ML) directions. Two switches were also mounted at the heel and toe in order to detect the gait phase. An able-bodied individual and a left hemiplegic patient with equinovarus participated. They wore the device and walked on a treadmill to investigate the device's functionality. [Results] Linear relationships between the torques and the corresponding output of the torque sensors were observed. Upon the analyses of gait of an able-body subject and a hemiplegic patient, we observed toque matrices in both AP and ML directions during the gait of the both subjects. [Conclusion] We developed a device capable of measuring the torque in the AP and ML directions of ankle joints during gait. PMID:26157244

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

    SciTech Connect

    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

    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.

  9. A wearable device as thin as a temporary tattoo can measure, store and transmit data on muscle

    E-print Network

    Priebe, Carey E.

    50 µm A wearable device as thin as a temporary tattoo can measure, store and transmit data on muscle activity, and release embedded drugs into the wearer's skin. Dae-Hyeong Kim at Seoul National. The nanomaterials acted as strain and temperature sensors, memory modules, microheaters and drug carriers

  10. The understanding levels of preservice teachers’ of basic science concepts’ measurement units and devices, their misconceptions and its causes

    Microsoft Academic Search

    Özgül Keles; Hülya Ertas; Naim Uzun; Mustafa Cansiz

    2010-01-01

    In this study it is aimed to determine preservice science teachers’ and elementary teachers’ level of understanding about measurement units, and devices; and misconceptions about basic science concepts (mass, weight, density, heat, temperature, energy, specific heat etc.). The sample included 92 undergraduate students who are second year preservice elementary teacher; and first and second year elementary science teacher. In this

  11. [Physical meaning of temperature measured by spectral line intensity method].

    PubMed

    Zhao, Wen-Hua; Tang, Huang-Zai; Shen, Yan; Shi, Yong; Hou, Ling-Yun

    2007-11-01

    The difference between electron temperature and excitation temperature is analyzed in the aspect of statistics thermodynamics. It is presented clearly that the temperature acquired by spectral line intensity method is not free electron temperature, but internal electronic excitation temperature of heavy particle. Under thermal equilibrium condition, the excitation temperature is equal to the electron temperature, while under non-thermal equilibrium condition, the excitation temperature is not equal to the electron temperature. In the study of arc jet plume in vacuum chamber, spectral line intensity method was employed to measure the apparent excitation temperature of arc jet plume, and Langmuir probe was employed to measure the electron temperature of arcjet plume. The big difference between the excitation temperature and the electron temperature proved that the temperature acquired by spectral line intensity method is not free electron temperature. PMID:18260380

  12. Device-independent quantum key distribution based on measurement inputs

    E-print Network

    Ramij Rahaman; Matthew G. Parker; Piotr Mironowicz; Marcin Paw?owski

    2015-05-17

    We provide an analysis of a new family of device independent quantum key distribution (QKD) protocols with several novel features: (a) The bits used for the secret key do not come from the results of the measurements on an entangled state but from the choices of settings; (b) Instead of a single security parameter (a violation of some Bell inequality) a set of them is used to estimate the level of trust in the secrecy of the key. The main advantage of these protocols is a smaller vulnerability to imperfect random number generators made possible by feature (a). We prove the security and the robustness of such protocols. We show that using our method it is possible to construct a QKD protocol which retains its security even if the source of randomness used by communicating parties is strongly biased. As a proof of principle, an explicit example of a protocol based on the Hardy's paradox is presented. Moreover, in the noiseless case, the protocol is secure in a natural way against any type of memory attack, and thus allows to reuse the device in subsequent rounds. We also analyse the robustness of the protocol using semi-definite programming methods. Finally, we present a post-processing method, and observe a paradoxical property that rejecting some random part of the private data can increase the key rate of the protocol.

  13. Instrument for Measuring Temperature of Water

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

    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.

  14. Infrared thermal detector array using Eu(TTA)3-based temperature sensitive paint for optical readable thermal imaging device

    NASA Astrophysics Data System (ADS)

    Wang, Min; Tsukamoto, Takashiro; Tanaka, Shuji

    2015-03-01

    This paper presents the design and fabrication of an infrared (IR) thermal detector array made of Eu(TTA)3-based temperature sensitive paint (TSP). The TSP emits 610?nm visible luminescence depending on temperature, and works as an IR-to-visible converter. An optical readout system was designed to excite and observe the detector array using a 355?nm light-emitting diode (LED) and a charge-coupled-device (CCD) camera, respectively. The temperature coefficient of the TSP was measured to be ?1.58%?K?1, and thermal images of a 400?°C object were successfully obtained. The noise analysis showed that the noise-equivalent temperature difference (NETD) of the imaging system was about 4.5?K.

  15. Two-sided laser device for online paper caliper measurement and control

    NASA Astrophysics Data System (ADS)

    Hughes, Michael K. Y.; Bengtsson, Markus; Hui, Pak; Duck, Graham

    2009-06-01

    Strong demand exists for a non-contacting paper caliper measurement which can be used as an input to a paper thickness control system. Caliper sensors requiring sheet contact suffer from errors related to dirt or coating build up and from high maintenance costs related to wear. These sensors can also damage the product by picking holes and marking sheets. Details of an on-line measurement device which employs two opposed laser displacement sensors and an inductive displacement sensor are presented. The sheet is held perpendicularly to the sensors with a Coanda air clamp. Dust and temperature control features which enable the sensor to operate reliably in an industrial environment are discussed. Results of production trials of this sensor are presented. Sub-micron profile agreement to lab and contacting caliper measurements has been demonstrated on light sheets. Results are presented of measurements on a wide range of paper grades from coated and uncoated light sheets to coated board.

  16. Equipment developed for static high temperature resistivity measurements

    Microsoft Academic Search

    Sandra H. Slivinsky

    1975-01-01

    Apparatus has been developed to accurately measure electrical resistivity as a function of temperature at high temperatures for metals and alloys. The resistivity of 0.254 mm diam tantalum wire has been measured between the temperatures 1170 and 2860 K. Temperature measurements were taken with an automatic optical pyrometer, a two-color ratio pyrometer, and a tungsten–rhenium thermocouple. The temperature observations were

  17. Equipment developed for static high temperature resistivity measurements

    Microsoft Academic Search

    Sandra H. Slivinsky

    1975-01-01

    Apparatus has been developed to accurately measure electrical resistivity as a function of temperature at high temperatures for metals and alloys. The resistivity of 0.254 mm diam tantalum wire has been measured between the temperatures 1170 and 2860 K. Temperature measurements were taken with an automatic optical pyrometer, a two-color ratio pyrometer, and a tungsten-rhenium thermocouple. The temperature observations were

  18. Field Test of Measurement-Device-Independent Quantum Key Distribution

    E-print Network

    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

    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.

  19. Measurement of temperature in active high-power AlGaN\\/GaN HFETs using Raman spectroscopy

    Microsoft Academic Search

    M. Kuball; J. M. Hayes; M. J. Uren; I. Martin; J. C. H. Birbeck; R. S. Balmer; B. T. Hughes

    2002-01-01

    We report on the noninvasive measurement of temperature, i.e., self-heating effects, in active AlGaN\\/GaN HFETs grown on sapphire and SiC substrates. Micro-Raman spectroscopy was used to produce temperature maps with ≈1 ?m spatial resolution and a temperature accuracy of better than 10°C. Significant temperature rises up to 180°C were measured in the device gate-drain opening. Results from a three-dimensional (3-D)

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

    SciTech Connect

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

    1994-12-31

    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.

  1. Device Performance

    SciTech Connect

    Not Available

    2006-06-01

    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.

  2. Fabrication of spintronic devices: etching endpoint detection by resistance measurement for magnetic tunnel junctions

    NASA Astrophysics Data System (ADS)

    Pong, Philip W. T.; Schmoueli, Moshe; Egelhoff, William F., Jr.

    2007-09-01

    Magnetic tunnel junctions (MTJs) have received tremendous interest since the discovery of substantial room temperature tunneling magnetoresistance (TMR) due to spin-dependent tunneling, and have been intensively investigated for applications in next-generation memory devices, hard disk drives, and magnetic sensors. In the fabrication of MTJs, etching is needed to remove the top cap layers, upper magnetic layers, and the middle oxide layer in order to form a tunneling junction. In view of this, we have devised an innovative, simple, low-cost endpoint detection method for fabricating MTJs. In this method, the endpoint is detected by measurement of the sheet resistance of the MTJ stack. Only a multimeter is needed in this method, hence it provides a simple low-cost alternative for spintronic device researchers to explore the research field of magnetic tunnel junctions. This technique is also of great use in other kinds of metallic stack etching experiments.

  3. Nonintrusive Measurement Of Temperature Of LED Junction

    NASA Technical Reports Server (NTRS)

    Leidecker, Henning; Powers, Charles

    1991-01-01

    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.

  4. Atomic origin of high-temperature electron trapping in metal-oxide-semiconductor devices

    NASA Astrophysics Data System (ADS)

    Shen, Xiao; Dhar, Sarit; Pantelides, Sokrates T.

    2015-04-01

    MOSFETs based on wide-band-gap semiconductors are suitable for operation at high temperature, at which additional atomic-scale processes that are benign at lower temperatures can get activated, resulting in device degradation. Recently, significant enhancement of electron trapping was observed under positive bias in SiC MOSFETs at temperatures higher than 150 °C. Here, we report first-principles calculations showing that the enhanced electron trapping is associated with thermally activated capturing of a second electron by an oxygen vacancy in SiO2 by which the vacancy transforms into a structure that comprises one Si dangling bond and a bond between a five-fold and a four-fold Si atoms. The results suggest a key role of oxygen vacancies and their structural reconfigurations in the reliability of high-temperature MOS devices.

  5. Soil moisture inferences from thermal infrared measurements of vegetation temperatures

    NASA Technical Reports Server (NTRS)

    Jackson, R. D. (principal investigator)

    1981-01-01

    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.

  6. Application of digital holography in temperature distribution measurement

    Microsoft Academic Search

    Guangjun Wang; Yan Li; Dayong Wang; Jie Zhao

    2010-01-01

    A reflection heat source including a radiator as well as an aluminum plate is designed, and the temperature field of the aluminum plate is used as the tested object. The reflection lensless Fourier transform (LFT) digital holography is performed to measure the temperature field distribution. For the comparison, the temperature measurement system within the radiator is used to measure the

  7. Reexamination of thermal transport measurements of a low-thermal conductance nanowire with a suspended micro-device.

    PubMed

    Weathers, Annie; Bi, Kedong; Pettes, Michael T; Shi, Li

    2013-08-01

    An increasingly used technique for measuring the thermal conductance of a nanowire is based on a suspended micro-device with built-in resistance thermometers. In the past, the technique has been limited to samples with thermal conductance larger than 1 × 10(-9) W/K because of temperature fluctuations in the sample environment and the presence of background heat transfer through residual gas molecules and radiation between the two thermometers. In addition, parasitic heat loss from the long supporting beams and asymmetry in the fabricated device results in two additional errors, which have been ignored in previous use of this method. To address these issues, we present a comprehensive measurement approach, where the device asymmetry is determined by conducting thermal measurements with two opposite heat flow directions along the nanowire, the background heat transfer is eliminated by measuring the differential heat transfer signal between the nanowire device and a reference device without a nanowire sample, and the parasitic heat loss from the supporting beams is obtained by measuring the average temperature rise of one of the beams. This technique is demonstrated on a nanofiber sample with a thermal conductance of 3.7 × 10(-10) W/K, against a background conductance of 8.2 × 10(-10) W/K at 320 K temperature. The results reveal the need to reduce the background thermal conductance in order to employ the micro-device to measure a nanowire sample with the thermal conductance less than 1 × 10(-10) W/K. PMID:24007092

  8. Probabilistic Design Optimization and Reliability Assessment of High Temperature Thermoelectric Devices

    SciTech Connect

    Jadaan, Osama M. [University of Wisconsin, Platteville; Wereszczak, Andrew A [ORNL

    2008-01-01

    Thermoelectric (TE) devices, subcomponents of which are made of brittle materials, generate an electrical potential when they are subjected to thermal gradients through their thickness. These devices are of significant interest for high temperature environments in transportation and industrial applications where waste heat can be used to generate electricity (also referred to as "waste heat recovery" or "energy harvesting"). TE devices become more efficient as larger thermal gradients are applied across them. This is accomplished by larger temperature differences across the TE's hot and cold junctions or the use of low thermal conductivity TE materials or both. However, a TE brittle material with a combination of poor strength, low thermal conductivity, and large coefficient of thermal expansion can translate into high probability of mechanical failure (low reliability) in the presence of a thermal gradient, thereby preventing its use as intended. Therefore, the objective of this work is to demonstrate the use of an established probabilistic design methodology developed for brittle structural components and corresponding design sensitivity analyses to optimize the reliability of an arbitrary TE device. This method can be used to guide TE material and design selection for optimum reliability. The mechanical reliability of a prototypical TE device is optimized from a structural ceramic perspective, using finite element analysis and the NASA CARES/Life integrated design code. Suggested geometric redesigns and material selection are identified to enhance the reliability of the TE device.

  9. Use of the Operant Orofacial Pain Assessment Device (OPAD) to Measure Changes in Nociceptive Behavior

    PubMed Central

    Anderson, Ethan M.; Mills, Richard; Nolan, Todd A.; Jenkins, Alan C.; Mustafa, Golam; Lloyd, Chris; Caudle, Robert M.; Neubert, John K.

    2013-01-01

    We present an operant system for the detection of pain in awake, conscious rodents. The Orofacial Pain Assessment Device (OPAD) assesses pain behaviors in a more clinically relevant way by not relying on reflex-based measures of nociception. Food fasted, hairless (or shaved) rodents are placed into a Plexiglas chamber which has two Peltier-based thermodes that can be programmed to any temperature between 7 °C and 60 °C. The rodent is trained to make contact with these in order to access a reward bottle. During a session, a number of behavioral pain outcomes are automatically recorded and saved. These measures include the number of reward bottle activations (licks) and facial contact stimuli (face contacts), but custom measures like the lick/face ratio (total number of licks per session/total number of contacts) can also be created. The stimulus temperature can be set to a single temperature or multiple temperatures within a session. The OPAD is a high-throughput, easy to use operant assay which will lead to better translation of pain research in the future as it includes cortical input instead of relying on spinal reflex-based nociceptive assays. PMID:23792907

  10. Silver-indium joints produced at low temperature for high temperature devices

    Microsoft Academic Search

    Ricky W. Chuang; Chin C. Lee

    2002-01-01

    A two-step fluxless bonding process adopted to produce high temperature silver-indium joints (80 wt% silver and 20 wt% indium) at relatively low process temperature of 206°C has been developed. After annealing the joint continuously for 26 h at 145°C, its melting temperature increases to 765-780°C, as confirmed by a de-bonding test. The technique thus developed provides a viable alternative to

  11. Measurement of surface temperature and emissivity of different materials by two-colour pyrometry

    NASA Astrophysics Data System (ADS)

    Raj, Vinay C.; Prabhu, S. V.

    2013-12-01

    An experimental investigation is performed to substantiate the capability of a charge coupled device camera to measure local temperature and emissivity of different materials heated to temperatures above 500 °C by two-colour pyrometric technique using colorimetric method. Materials investigated are Inconel 718 with pyromark (high temperature paint), Inconel 718, stainless steel SS 304 and SS 316. Centerline temperature and emissivity distribution is obtained for target plates maintained at constant temperature by AC heating while complete temperature and emissivity distribution is provided for plates heated by flame impingement. The obtained results are compared with a calibrated infrared camera and thermocouples and the temperature distribution is found to be in close agreement. These results pertain to partially oxidized metal alloys covered in this study. Deviation in the measurement of emissivity can be attributed to its dependence on wavelength range, oxidation, and sensitivity of the image detector.

  12. A linear, temperature compensated, high frequency salinity measuring device

    E-print Network

    Kelly, Minton Jones

    1951-01-01

    ;. nt ~e to &ieviee an instruaent &hlch 1&oui&3. algren&1 thP, v! luce in thi s reI"ion nn&3 Pt the s"L&le time ~ht?in lin~c&r3. t3&. The . -. &iv"ntsges that; . . ccrue from t&i-. hiI'h fre. uanc; nethn& because p its et=bilit3& anil. lao'. " o...

  13. A linear, temperature compensated, high frequency salinity measuring device 

    E-print Network

    Kelly, Minton Jones

    1951-01-01

    ;. nt ~e to &ieviee an instruaent &hlch 1&oui&3. algren&1 thP, v! luce in thi s reI"ion nn&3 Pt the s"L&le time ~ht?in lin~c&r3. t3&. The . -. &iv"ntsges that; . . ccrue from t&i-. hiI'h fre. uanc; nethn& because p its et=bilit3& anil. lao'. " o... since the &&eveloi- ("-II npI&t o& the hi&, "h frequenov titr3neter by Jensen sn&1 3'arrac'~ ~one ttegnts hsva bean &a&c'g I;o:ro&luce ". hi h free&uenc3& ataxia&ent for ?. ;enerc&l s?nl? tic;l &n&r. ' ho'~&ever Lt is thou&-, ht th-lt snticfnatory...

  14. Indium arsenide quantum well hall devices for room-temperature detection of magnetic biomolecular labels

    NASA Astrophysics Data System (ADS)

    Mihajlovic, Goran

    This dissertation presents work on fabrication and room-temperature characterization of mesoscopic Hall sensors from InAs/AlSb quantum well semiconductor heterostructures. It also demonstrates suitability of these devices for detection of micro- and submicrometer-sized superparamagnetic beads that can be used as biomolecular labels in the newly proposed concept of magnetic biomolecular sensing. Detailed analytical analysis of physical factors which determine the magnetic field and the magnetic moment resolution of cross-shaped Hall sensors is presented. The analysis shows that materials with low Hooge's 1/f noise parameter, low density of active charge traps, high carrier mobility and, contrary to the common opinion, high electron density provide the best physical medium for fabricating ultra-sensitive miniaturized Hall sensors. Systematic room-temperature Hall coefficient and electronic noise measurements have been carried out on the sensors with the Hall cross widths of 1 mum and 250 nm. In the low frequency range, from 20 Hz to 1.6 kHz, the sensors show magnetic moment sensitivities on the order of 106 mu B/ Hz and 105 muB/ Hz respectively, where muB is the Bohr magneton. For 250 nm devices, the moment sensitivity reaches the values in 104 muB/ Hz range above ˜ 1 kHz. By using phase-sensitive detection technique based on non-linear magnetization response of superparamagnetic beads to external magnetic field, the presence of a single bead, 1.2 mum in diameter and suitable for biological applications, on the micron-sized Hall cross has been detected with signal to noise ratio of ˜ 33.3 dB. Micro-Hall susceptibility measurements and the subsequent data analysis have shown that the bead consists of ensemble of non-interacting magnetic nanoparticles with broad distribution of magnetic moments. The mean magnetic moment and the mean diameter of nanoparticles in the bead were found to be ˜ 1.55 x 104 mu B and 8.3 nm respectively. Additionally, detection of 250 nm beads has been achieved with signal to noise ratio of 2.3 dB per single bead.

  15. A single chip broadband noise source for noise measurements at cryogenic temperatures

    Microsoft Academic Search

    D. Bruch; F. Schafer; M. Seelmann-Eggebert; B. Aja; I. Kallfass; A. Leuther; M. Schlechtweg; O. Ambacher

    2011-01-01

    This paper presents the design and performance of a single chip broadband noise source dedicated for on-chip measurements in a cryogenic environment. The noise source is used to generate the two input noise powers Pc and Ph which are required by the commonly used Y-factor method. High accuracy in temperature control and impedance presented to the device under test is

  16. Self-balancing line-reversal pyrometer automatically measures gas temperatures

    NASA Technical Reports Server (NTRS)

    Buchele, D.

    1967-01-01

    Automatic line-reversal pyrometer measures gas temperatures from 2900 degrees to 4500 degrees R. The self-balancing device uses the sodium D-line but replaces the two conventional manual operations of the line-reversal method and can be used by semiskilled personnel.

  17. Quantum efficiency measurements in the swept charge device CCD236

    NASA Astrophysics Data System (ADS)

    Smith, P. H.; Gow, J. P. D.; Murray, N. J.; Tutt, J. H.; Soman, M. R.; Holland, A. D.

    2014-04-01

    The e2v technologies plc. CCD236 is a Swept Charge Device (SCD) designed as a large area (20 mm × 20 mm) soft X-ray detector for spectroscopy in the range 0.8 keV to 10 keV. It benefits from improvements in design over the previous generation, the e2v CCD54, such as: a 4 times increased detector area, a reduction in split X-ray events due to the 100 ?m × 100 ?m `pixel' size, and improvements to radiation hardness. The CCD236 will be used in India's Chandrayaan-2 Large Soft X-ray Spectrometer (CLASS) instrument and China's Hard X-ray Modulation Telescope (HXMT). Measurements of the Quantum Efficiency (QE) have been obtained relative to a NIST calibrated photodiode over the energy range 0.2 keV to 1.9 keV, using the BESSY II X-ray synchrotron in Berlin. Two X-ray event counting methods are described and compared, and QE for soft X-ray interaction is reported. Uniformity of QE across the device is also investigated at energies between 0.52 keV and 1.5 keV in different areas of the detector. This work will enable the actual number of photons incident on the detectors to be calculated, thus ensuring that the CCD236 detectors provide valuable scientific data during use. By comparing the QE methods in this paper with the event processing techniques to be used with CLASS, an estimate of the instrument-specific QE for CLASS can be provided.

  18. Predicting the effect of temperature on the performance of elastomer-based rail damping devices

    Microsoft Academic Search

    N. Ahmad; D. J. Thompson; C. J. C. Jones; A. H. Muhr

    2009-01-01

    Damping devices for railway tracks have been developed in recent years in which a tuned mass-spring absorber system is formed by an elastomeric material and embedded steel masses. The loss factor and stiffness of the elastomer are very important for the performance of the system but, unfortunately, both properties are sensitive to changes in the temperature. Although having a high

  19. Fabrication of a LCP-based conductivity cell and resistive temperature device via PCB MEMS technology

    Microsoft Academic Search

    Heather A Broadbent; Stanislav Z Ivanov; David P Fries

    2007-01-01

    Printed circuit board microelectromechanical systems are a set of fabrication techniques that use traditional inexpensive printed circuit board processes to construct microsensors. These techniques keep gaining popularity and are utilized herein. The design, fabrication and construction of a miniature, low-cost conductivity cell and resistive temperature device transducers are presented. The transducers utilize a liquid crystal polymer (LCP), a thin-film material,

  20. Methodological investigation of measuring nasopharyngeal temperature as noninvasive brain temperature analogue in the neonate

    Microsoft Academic Search

    Hae-Kyung Ko; Andreas Flemmer; Caroline Haberl; Georg Simbruner

    2001-01-01

    Objectives: (a) To investigate in a newborn animal model whether nasopharyngeal temperature is more closely related to epidural brain temperature than rectal temperature and (b) to investigate in human neonates whether measurement of nasopharyngeal temperature is dependent on the measurement site and other conditions. Design and setting: (a) Animal experiment in newborn piglets, at an institute for surgical research. (b)

  1. Air temperature profile and air/sea temperature difference measurements by infrared and microwave scanning radiometers

    E-print Network

    Shaw, Joseph A.

    Air temperature profile and air/sea temperature difference measurements by infrared and microwave air temperature profile and air/sea temperature difference. The main advantage of this technique measurements, accounting for air attenuation and sea surface roughness. Then we show retrieval results

  2. Measurement of cloud point temperature in polymer solutions.

    PubMed

    Mannella, G A; La Carrubba, V; Brucato, V

    2013-07-01

    A temperature-controlled turbidity measurement apparatus for the characterization of polymer solutions has been instrumented and set up. The main features are the coupled temperature-light transmittance measurement and the accurate temperature control, achieved by means of peltier cells. The apparatus allows to measure cloud point temperatures by adopting different cooling protocols: low rate for quasi-equilibrium measurements and high rate for detect kinetic effects. A ternary polymeric solution was adopted as case study system showing that cooling rate affects the measured cloud point temperature. PMID:23902117

  3. Bulk temperature measurement in thermally striped pipe flows

    SciTech Connect

    Lemure, N.; Olvera, J.R.; Ruggles, A.E. [Univ. of Tennessee, Knoxville, TN (United States). Coll. of Engineering

    1995-12-01

    The hot leg flows in some Pressurized Water Reactor (PWR) designs have a temperature distribution across the pipe cross-section. This condition is often referred to as a thermally striped flow. Here, the bulk temperature measurement of pipe flows with thermal striping is explored. An experiment is conducted to examine the feasibility of using temperature measurements on the external surface of the pipe to estimate the bulk temperature of the flow. Simple mixing models are used to characterize the development of the temperature profile in the flow. Simple averaging techniques and Backward Propagating Neural Net are used to predict bulk temperature from the external temperature measurements. Accurate bulk temperatures can be predicted. However, some temperature distributions in the flow effectively mask the bulk temperature from the wall and cause significant error in the bulk temperature predicted using this technique.

  4. Crowdsourcing urban air temperature measurements using smartphones

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2013-10-01

    Crowdsourced data from cell phone battery temperature sensors could be used to contribute to improved real-time, high-resolution air temperature estimates in urban areas, a new study shows. Temperature observations in cities are in some cases currently limited to a few weather stations, but there are millions of smartphone users in many cities. The batteries in cell phones have temperature sensors to avoid damage to the phone.

  5. Refractory thermowell for continuous high temperature measurement of molten metal

    DOEpatents

    Thiesen, Todd J. (Idaho Falls, ID)

    1992-01-01

    An apparatus for the continuous high temperature measurement of materials in vessels lined with rammed or cast refractory materials. A refractory housing member is integral with the refractory lining of the vessel and contains a plurality of high temperature sensing means, such as thermocouples. A face of the housing is flush with the refractory lining and contacts the high temperature material contained in the vessel. Continuous temperature measurement is achieved by a means which is coupled to the thermocouples for indicating the temperature.

  6. Fixation Stability Measurement Using Two Types of Microperimetry Devices

    PubMed Central

    Liu, Hongting; Bittencourt, Millena G.; Sophie, Raafay; Sepah, Yasir J.; Hanout, Mostafa; Rentiya, Zubir; Annam, Rachel; Scholl, Hendrik P. N.; Nguyen, Quan Dong

    2015-01-01

    Purpose We compared the fixation stability measurements obtained with two microperimeters, the Micro Perimeter 1 (MP-1) and the Spectral OCT/SLO (OCT/SLO), in subjects with and without maculopathies. Methods A total of 41 eyes with no known ocular diseases and 45 eyes with maculopathies were enrolled in the study. Both eyes of each participant had a 20-second fixation test using the MP-1 and OCT/SLO. The bivariate contour ellipse area (BCEA) was used for fixation stability evaluation. Results In the normal group, BCEA was 2.93 ± 0.32 log minarc2 on OCT/SLO and 2.89 ± 0.30 log minarc2 on MP-1. In the maculopathy group, BCEA was 3.05 ± 0.41 log minarc2 on OCT/SLO and 3.15 ± 0.46 log minarc2 on MP-1. There was no statistically significant difference between the BCEA measured by OCT/SLO and by MP-1 in both groups. A moderate correlation was found between the two devices (r = 0.45, P < 0.001). The sample size during the fixation test was 535.5 ± 14.6 pairs of coordinates in the normal group and 530.7 ± 14.9 pairs in the maculopathy group with MP-1, while it was 72.3 ± 6.9 and 59.9 ± 10.1, respectively, with OCT/SLO. This was due to different tracking frequencies between the two microperimeters. Conclusion Fixation stability assessment yields similar results using the OCT/SLO and MP-1. A major difference in sampling rate between the two microperimeters does not significantly affect BCEA measurements. Translational Relevance Fixation stability assessments are comparable and interchangeable between the OCT/SLO and the MP-1. PMID:25774329

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

    E-print Network

    California at San Diego, University of

    Temperature and anisotropic-temperature relaxation measurements in cold, pure-electron plasmas B. R not be equal, and, when unequal, we have measured the relaxation rate at which electron­electron collisions; accepted 3 January 1996 Plasma temperatures in the range 25 to 2 106 K have been measured using a cryogenic

  8. The measurement of sea surface temperature with an infrared radiometer

    Microsoft Academic Search

    C. Braun; D. Mercer

    1970-01-01

    The purpose of this experiment was to make simultaneous measurements of sea surface temperature with infrared and microwave radiometers. Such measurements should be useful for determining the accuracy of satellite radiometer measurements of sea surface temperatures. Measurements were made with RCA personnel as part of PROJECT ROCKFISH, at a test site on the Chesapeake Bay Bridge Tunnel near Norfolk, Virginia.

  9. Studies on room-temperature electric-field effect in ionic-liquid gated VO2 three-terminal devices

    NASA Astrophysics Data System (ADS)

    Yang, Zheng; Zhou, You; Ramanathan, Shriram

    2012-01-01

    We present a study of electrostatic gating of VO2 thin films in ionic-liquid-based electric double-layer transistor geometry. Devices were fabricated by lithographic patterning of VO2 thin films as channel on sapphire substrates, ionic liquid as gate dielectric, and Au as gate/source/drain electrode, respectively. A significant unipolar increase in channel conductance at room temperature is observed. The VO2 channel resistance decreases ˜50% at + 2 V gate bias, whereas it increases slightly under negative bias. The polarity dependence of resistance modulation suggests electrons to be a dominant carrier, which is consistent with Hall measurements. In the high-temperature metallic state of VO2, no gating effect is observed. The effect of multiple transition cycles on the channel resistance change under bias is discussed. The study contributes to on-going efforts to realize room-temperature field-effect switches with correlated oxides.

  10. Floating Probe Assembly for Measuring Temperature of Water

    NASA Technical Reports Server (NTRS)

    Stewart, Randy; Ruffin, Clyde

    2003-01-01

    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.

  11. Axillary and Rectal Temperature Measurements Poorly Agree in Newborn Infants

    Microsoft Academic Search

    P. C. E. Hissink Muller; L. H. van Berkel; A. J. de Beaufort

    2008-01-01

    Aim: Evaluation of the agreement between axillary temperature measurements and rectal temperature measurements in neonates. Methods: Rectal and axillary body temperatures were simultaneously measured for 3 min in 33 neonates (gestational age 25–42 weeks, weight 840–4,005 g). Two investigators performed paired measurements, one in each neonate. A single type of thermometer was used in this study: one thermometer for each

  12. Application of digital holography in temperature distribution measurement

    NASA Astrophysics Data System (ADS)

    Wang, Guangjun; Li, Yan; Wang, Dayong; Zhao, Jie

    2010-11-01

    A reflection heat source including a radiator as well as an aluminum plate is designed, and the temperature field of the aluminum plate is used as the tested object. The reflection lensless Fourier transform (LFT) digital holography is performed to measure the temperature field distribution. For the comparison, the temperature measurement system within the radiator is used to measure the temperature distributions. The results obtained by these two methods are in good agreement, which demonstrates that the digital holography method is valid for the measurement of the temperature distribution.

  13. Water temperature-influential factors, field measurement, and data presentation

    USGS Publications Warehouse

    Stevens, Herbert H.; Ficke, John F.; Smoot, George F.

    1975-01-01

    This manual contains suggested procedures for collecting and reporting of water-temperature data on streams, lakes and reservoirs, estuaries, and ground water. Among the topics discussed are the selection of equipment and measuring sites, objectives and accuracy of measurements, and data processing and presentation. Background information on the influence of temperature on water quality and the factors influencing water temperature are also presented.

  14. Scanning infrared radiometer for measuring the airsea temperature difference

    E-print Network

    Shaw, Joseph A.

    when the air­sea temperature difference is negative, and Hwang and Shemdin3 showed that sea-surfaceScanning infrared radiometer for measuring the air­sea temperature difference Joseph A. Shaw a vertically scanning infrared radiometer for measuring the air­sea temperature difference without disturbing

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

    SciTech Connect

    Suda, S.; Keisch, B.

    1993-08-01

    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: tip of probe, response proportional to the length of probe, top of tank, and liquid surface. This paper describes the physical principles of pressure, capacitance probe, sonic reflections, and visual scales. These are representative of the four types of liquid level detection techniques. Development of the temperature correction algorithm requires that the measurement process be clearly defined, conditions or limitations specified, and that a temperature-effects test be run. Although not difficult or necessarily time-consuming to run, good practice requires a test plan following demonstrated guidelines. Measurement control procedures for remeasurement of the process solution in the tank during normal operation can provide data to validate temperature correction algorithms.

  16. Stream temperature dynamics: Measurements and modeling

    Microsoft Academic Search

    Bashar A. Sinokrot; Heinz G. Stefan

    1993-01-01

    A numerical model based on a finite difference solution of the unsteady heat advection-dispersion equation is formulated to predict water temperatures in streams at time increments of 1 hour. An energy balance accounts for the effects of air temperature, solar radiation, relative humidity, cloud cover, and wind speed on the net rate of heat exchange through the water surface, and

  17. Global trends of measured surface air temperature

    Microsoft Academic Search

    James Hansen; Sergej Lebedeff

    1987-01-01

    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

  18. Sea surface temperature measurements with AIRS

    NASA Technical Reports Server (NTRS)

    Aumann, H.

    2003-01-01

    The comparison of global sea surface skin temperature derived from cloud-free AIRS super window channel at 2616 cm-1 (sst2616) with the Real-Time Global Sea Surface Temperature for September 2002 shows surprisingly small standard deviation of 0.44K.

  19. Two methods of temperature control for single-molecule measurements.

    PubMed

    Baker, Matthew A B; Inoue, Yuichi; Takeda, Kuniaki; Ishijima, Akihiko; Berry, Richard M

    2011-05-01

    Modern single-molecule biophysical experiments require high numerical aperture oil-immersion objectives in close contact with the sample. We introduce two methods of high numerical aperture temperature control which can be implemented on any microscope: objective temperature control using a ring-shaped Peltier device, and stage temperature control using a fluid flow cooling chip in close thermal contact with the sample. We demonstrate the efficacy of each system by showing the change in speed with temperature of two molecular motors, the bacterial flagellar motor and skeletal muscle myosin. PMID:21279639

  20. Integration of High Dose Boron Implants--Modification of Device Parametrics through Implant Temperature Control

    SciTech Connect

    Schmeide, Matthias [Infineon Technologies Dresden GmbH, Koenigsbruecker Str. 180, D-01099 Dresden (Germany); Ameen, M. S.; Kondratenko, Serguei; Krimbacher, Bernhard; Reece, Ronald N. [Axcelis Technologies, Inc., 108 Cherry Hill Dr., Beverly, MA, 01915 (United States)

    2011-01-07

    In the present study, we have extended a previously reported 250 nm logic p-S/D implant (7 keV B 4.5x10{sup 15} cm{sup -2}) process matching exercise [5] to include wafer temperature, and demonstrate that matching can be obtained by increasing the temperature of the wafer during implant. We found that the high dose rate delivered by the single wafer implanter caused the formation of a clear amorphous layer, which upon subsequent annealing altered the diffusion, activation, and clustering properties of the boron. Furthermore, increasing the temperature of the wafer during the implant was sufficient to suppress amorphization, allowing profiles and device parameters to become matched. Figure 5 shows a representative set of curves indicating the cluster phenomena observed for the lower temperature, high flux single wafer implanter, and the influence of wafer temperature on the profiles. The results indicate the strong primary effect of dose rate in determining final electrical properties of devices, and successful implementation of damage engineering using wafer temperature control.

  1. Titan's Surface Temperatures Measured by Cassini CIRS

    NASA Technical Reports Server (NTRS)

    Jennings, Donald E.; Flasar, F. M.; Kundle, V. G.; Samuelson, R. E.; Pearl, J. C.; Nixon, C. A.; Carlson, R. C.; Mamoutkine, A. A.; Brasunas, J. C.; Guandique, E.; Arhterberg, R. K.; Bjoraker, G. L.; Romani, P. N.; Segura, M. E.; Albright, S. A.; Elliott, M. H.; Tingley, J. S.; Calcutt, S.; Coustenis, A.; Bezard, B.; Courtin, R.

    2008-01-01

    A large fraction of 19-micron thermal radiation from the surface of Titan reaches space through a spectral window of low atmospheric opacity. The emergent radiance, after removing the effect of the atmosphere, gives the brightness temperature of the surface. This atmospheric window is covered by the far-infrared channel of the Composite Infrared spectrometer1 (CIRS) on Cassini. In mapping Titan surface temperatures, CIRS is able to improve upon results of Voyager IRIS, by taking advantage of improved latitude coverage and a much larger dataset. Observations are from a wide range of emission angles and thereby provide constraints on the atmospheric opacity and radiance that are used to derive the surface temperature. CIRS finds an average equatorial surface brightness temperature of 93.7+/-0.6 K, virtually identical to the HASI temperature at the Huygens landing site. Mapping in latitude shows that the surface temperature decreases toward the poles by about 2 K in the south and 3 K in the north. This surface temperature distribution is consistent with the formation of lakes seen at high latitudes on Titan.

  2. 55Measuring Star Temperatures The lower plot shows

    E-print Network

    55Measuring Star Temperatures The lower plot shows measurements of the spectrum of the star HD in nanometers. A) Antares ....................... 3,100 K B) Zeta Orionis............... 30,000 K C) Vega measurements of a star's light spectrum gives astronomers clues about its temperature. For example

  3. Validation of temperature measurements from the Halogen Occultation Experiment

    Microsoft Academic Search

    M. E. Hervig; J. M. Russell; L. L. Gordley; S. R. Drayson; K. Stone; R. E. Thompson; M. E. Gelman; I. S. McDermid; A. Hauchecorne; P. Keckhut; T. J. McGee; U. N. Singh; M. R. Gross

    1996-01-01

    The Halogen Occultation Experiment (HALOE) onboard UARS measures profiles of limb path solar attenuation in eight infrared bands. These measurements are used to infer profiles of temperature, gas mixing ratios of seven species, and aerosol extinction at five wavelengths. The objective of this paper is to validate profiles of temperature retrieved from atmospheric transmission measurements in the 2.80-mum CO2 band.

  4. Turbine Blade Temperature Measurements Using Thin Film Temperature Sensors

    NASA Technical Reports Server (NTRS)

    Grant, H. P.; Przybyszewski, J. S.; Claing, R. G.

    1981-01-01

    The development of thin film temperature sensors is discussed. The technology for sputtering 2 micron thin film platinum versus platinum 10 percent rhodium thermocouples on alumina forming coatings was improved and extended to applications on actual turbine blades. Good adherence was found to depend upon achieving a proper morphology of the alumina surface. Problems of adapting fabrication procedures to turbine blades were uncovered, and improvements were recommended. Testing at 1250 K at one atmosphere pressure was then extended to a higher Mach No. (0.5) in combustor flow for 60 hours and 71 thermal cycles. The mean time to failure was 47 hours accumulated during 1 hour exposures in the combustor. Calibration drift was about 0.1 percent per hour, attributable to oxidation of the rhodium in the thin films. An increase in film thickness and application of a protective overcoat are recommended to reduce drift in actual engine testing.

  5. Radiometric Techniques for Emissivity and Temperature Measurements for Industrial Applications

    NASA Astrophysics Data System (ADS)

    Vuelban, E. M.; Girard, F.; Battuello, M.; Neme?ek, P.; Maniur, M.; Pavlásek, P.; Paans, T.

    2015-05-01

    Radiometric techniques for temperature measurements are indispensable in industrial applications, particularly when the use of contact thermometers is hard or impossible to realize. The principles and realizations of some new and extended radiometric techniques for measuring the emissivity and temperature of an object are presented. Using the described techniques, the emissivity and temperature of an Inconel 600 sample at high temperatures in laboratory conditions were determined. The validation of the temperature measurement of the same sample in a simulated industrial condition is also presented.

  6. Parallel DNA amplification by convective polymerase chain reaction with various annealing temperatures on a thermal gradient device.

    PubMed

    Zhang, Chunsun; Xing, Da

    2009-04-01

    We present a thermal gradient convective polymerase chain reaction (PCR) for parallel DNA amplification with different annealing temperatures. The thermal gradient for microfluidic gradient PCR is produced by an innovative fin design whose formation principle is given. Without the need for a pump, the buoyancy forces continuously circulate reagents in a closed loop through different thermal zones, which brings self-actuated convective-flow PCR. In our prototype, we measured a temperature difference of about 45 degrees C along the gradient direction on the copper flake (45 x 40 x 4 mm). When the temperature of the hot zone is 90-97 degrees C and the temperature of the cold zone is 60-70 degrees C, the convection triggered two-temperature amplification of 112-bp fragment of Escherichia coli DNA. The time for amplification is less than 45 min. Interestingly, parallel DNA amplification with different annealing temperatures ranging from 60 to 70 degrees C was performed by this method. The PCR thermocycler demonstrated herein can be further scaled down and the loop length can be further reduced, and therefore the PCR times can be further reduced. These devices are suited as a platform for a new generation of low-power, portable DNA analysis systems. PMID:19454245

  7. Temperature measurement. [liquid monopropellant rocket engine performance tests

    NASA Technical Reports Server (NTRS)

    1979-01-01

    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.

  8. Note: low temperature superconductor superconducting quantum interference device system with wide pickup coil for detecting small metallic particles.

    PubMed

    Kandori, Akihiko; Ogata, Kuniomi; Kawabata, Ryuzo; Tanimoto, Sayaka; Seki, Yusuke

    2012-07-01

    A one-channel low temperature superconductor superconducting quantum interference device system comprising a second-order axial gradiometer with a sensing area of 10 mm × 190 mm was developed. The gradiometer was mounted in a liquid-helium dewar (450-mm diameter; 975-mm length), with a gap of 12 mm between the pickup coil and the dewar-tail surface. The magnetic field sensitivity was measured to be 16 fT/Hz(1/2) in the white noise regime above 2 Hz. The system was used to measure stainless steel particles of different sizes passing through the sensing area. A 100-?m diameter SUS304 particle was readily detected passing at different positions underneath the large pickup coil by measuring its 1.3-pT magnetic field. Thus, the system was shown to be applicable to quality control of lamination sheet products such as lithium ion batteries. PMID:22852743

  9. Note: Low temperature superconductor superconducting quantum interference device system with wide pickup coil for detecting small metallic particles

    NASA Astrophysics Data System (ADS)

    Kandori, Akihiko; Ogata, Kuniomi; Kawabata, Ryuzo; Tanimoto, Sayaka; Seki, Yusuke

    2012-07-01

    A one-channel low temperature superconductor superconducting quantum interference device system comprising a second-order axial gradiometer with a sensing area of 10 mm × 190 mm was developed. The gradiometer was mounted in a liquid-helium dewar (450-mm diameter; 975-mm length), with a gap of 12 mm between the pickup coil and the dewar-tail surface. The magnetic field sensitivity was measured to be 16 fT/Hz1/2 in the white noise regime above 2 Hz. The system was used to measure stainless steel particles of different sizes passing through the sensing area. A 100-?m diameter SUS304 particle was readily detected passing at different positions underneath the large pickup coil by measuring its 1.3-pT magnetic field. Thus, the system was shown to be applicable to quality control of lamination sheet products such as lithium ion batteries.

  10. An integrated device for magnetically-driven drug release and in situ quantitative measurements: Design, fabrication and testing

    NASA Astrophysics Data System (ADS)

    Bruvera, I. J.; Hernández, R.; Mijangos, C.; Goya, G. F.

    2015-03-01

    We have developed a device capable of remote triggering and in situ quantification of therapeutic drugs, based on magnetically-responsive hydrogels of poly (N-isopropylacrylamide) and alginate (PNiPAAm). The heating efficiency of these hydrogels measured by their specific power absorption (SPA) values showed that the values between 100 and 300 W/g of the material were high enough to reach the lower critical solution temperature (LCST) of the polymeric matrix within few minutes. The drug release through application of AC magnetic fields could be controlled by time-modulated field pulses in order to deliver the desired amount of drug. Using B12 vitamin as a concept drug, the device was calibrated to measure amounts of drug released as small as 25(2)×10-9 g, demonstrating the potential of this device for very precise quantitative control of drug release.

  11. A room-temperature single-electron memory device using fine-grain polycrystalline silicon

    Microsoft Academic Search

    Kazuo Yano; Tomoyuki Ishii; Takashi Hashimoto; Takashi Kobayashi; Fumio Murai; Koichi Seki

    1993-01-01

    The first room-temperature operation is demonstrated of a single-electron memory device, in which an electron represents one-bit information. This is made possible due to our new one-transistor memory configuration (conventionally three circuit elements are needed), which has very high charge sensitivity. Another new technique, which stabilizes the one-electron stored state, is ultra-thin (4 nm) poly-Si film for the active region,

  12. Development of Nickel Wire Bonding for High-Temperature Packaging of SiC Devices

    Microsoft Academic Search

    Ravi K. Burla; Li Chen; Christian A. Zorman; Mehran Mehregany

    2009-01-01

    This paper describes a detailed investigation of an ultrasonic nickel wire bonding technique for silicon carbide (SiC) devices, and its comparison with a thermosonic wire bonding process, for high-temperature applications. The study focuses on bonding 25-mum-diameter Ni wires to 750-nm-thick Ni pads deposited on 3C-SiC substrates. First, the Ni wire bonding recipe is optimized for maximum bond strength using a

  13. High temperature LGS SAW devices with Pt\\/WO3 and Pd sensing films

    Microsoft Academic Search

    J. A. Thiele; M. Pereira da Cunha

    2003-01-01

    This paper reports on the fabrication of high temperature LGS SAW devices to be used as gas sensors. SAW resonators and delay lines have been designed, fabricated, and tested up to 750°C. An additional 7dB loss in the transmission coefficient, |S21|, of the two port 167 MHz SAW resonators tested has been observed for operation at 750°C with respect to

  14. Novel devices for solvent delivery and temperature programming designed for capillary liquid chromatography.

    PubMed

    Coutinho, Lincoln Figueira Marins; Nazario, Carlos Eduardo Domingues; Monteiro, Alessandra Maffei; Lanças, Fernando Mauro

    2014-08-01

    Analyses in chromatographic systems able to save mobile and stationary phases without reducing efficiency and resolution are of current interest. These advantages regarding savings have challenged us to develop a system dedicated to miniaturized liquid chromatography. This paper reports on the development of a high-pressure syringe-type pump, an oven able to perform isothermal and temperature programming and a software program to control these chromatographic devices. The experimental results show that the miniaturized system can generate reproducible and accurate temperature and flow rate. The system was applied to the separation of statins and tetracylines and showed excellent performance. PMID:24838528

  15. Effects of nuclear radiation and elevated temperature storage on electroexplosive devices

    NASA Technical Reports Server (NTRS)

    Menichelli, V. J.

    1976-01-01

    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.

  16. Dielectric property measurement of zirconia fibers at high temperatures

    SciTech Connect

    Vogt, G.J. [Los Alamos National Lab., NM (United States); Tinga, W.R. [Univ. of Alberta, Edmonton (Canada). Dept. of Electrical Engineering; Plovnick, R.H. [3M Ceramic Technology Center, St. Paul, MN (United States)

    1995-05-01

    Using a self-heating, electronically tunable microwave dielectrometer, the complex dielectric constant of zirconia-based filaments was measured at 915 MHz from 350{degrees} to 1100{degrees}C. This fibrous material cools rapidly to near room temperature within several seconds due to a large surface area to volume ratio. Such rapid sample cooling necessitates the use of a self-heating technique to measure the complex dielectric constant at temperatures up to 1100{degrees}C. Sample temperature was measured with optical fiber thermometry. The effect of sample temperature measurement on data accuracy is discussed.

  17. Active radiometer for self-calibrated furnace temperature measurements

    DOEpatents

    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

    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.

  18. TEMPERATURE MEASUREMENT SYSTEM OF NOVOSIBIRSK FREE ELECTRON LASER

    E-print Network

    Kozak, Victor R.

    . These sensors are installed on the floor of the accelerator hall. If water gets between these plates of the accelerator hall. 3. Vacuum "sensors". These sensors are actually control devices for vacuum pumps from a large number of temperature sensors installed on different parts of the FEL facility, which

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

    NASA Technical Reports Server (NTRS)

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

    2012-01-01

    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.

  20. A Low-Cost Thermistor Device for Measurements of Metabolic Heat in Yeast Cells in Suspension.

    ERIC Educational Resources Information Center

    Keeling, Richard P.

    1980-01-01

    Provides illustrated directions for the construction and use of a low-cost thermistor device. Attached to a servo-type millivolt chart recorder, the device will record minute temperature changes and will simulate data obtained from an oxygen polarograph. Includes results of experiments with baker's yeast. (Author/CS)

  1. Measurement and correlation of jet fuel viscosities at low temperatures

    NASA Technical Reports Server (NTRS)

    Schruben, D. L.

    1985-01-01

    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.

  2. Thermal management of BioMEMS: temperature control for ceramic-based PCR and DNA detection devices

    Microsoft Academic Search

    Daniel J. Sadler; Rajnish Changrani; Peter Roberts; Chia-Fu Chou; Frederic Zenhausern

    2003-01-01

    Integrated microfluidic devices for amplification and detection of biological samples that employ closed-loop temperature monitoring and control have been demonstrated within a multilayer low temperature co-fired ceramics (LTCC) platform. Devices designed within this platform demonstrate a high level of integration including integrated microfluidic channels, thick-film screen-printed Ag-Pd heaters, surface mounted temperature sensors, and air-gaps for thermal isolation. In addition, thermal-fluidic

  3. Design and development of a heart rate measuring device using fingertip

    Microsoft Academic Search

    M. M. A. Hashem; R. Shams; M. A. Kader; M. A. Sayed

    2010-01-01

    In this paper, we presented the design and development of a new integrated device for measuring heart rate using fingertip to improve estimating the heart rate. As heart related diseases are increasing day by day, the need for an accurate and affordable heart rate measuring device or heart monitor is essential to ensure quality of health. However, most heart rate

  4. Temperature control during therapeutic hypothermia for newborn encephalopathy using different Blanketrol devices.

    PubMed

    Laptook, Abbot R; Kilbride, Howard; Shepherd, Edward; McDonald, Scott A; Shankaran, Seetha; Truog, William; Das, Abhik; Higgins, Rosemary D

    2014-12-01

    Therapeutic hypothermia improves the survival and neurodevelopmental outcome of infants with newborn encephalopathy of a hypoxic-ischemic origin. The NICHD Neonatal Research Network (NRN) Whole Body Cooling trial used the Cincinnati Sub-Zero Blanketrol II to achieve therapeutic hypothermia. The Blanketrol III is now available and provides additional cooling modes that may result in better temperature control. This report is a retrospective comparison of infants undergoing hypothermia using two different cooling modes of the Blanketrol device. Infants from the NRN trial were cooled with the Blanketrol II using the Automatic control mode (B2 cohort) and were compared with infants from two new NRN centers that adopted the NRN protocol and used the Blanketrol III in a gradient mode (B3 cohort). The primary outcome was the percent time the esophageal temperature stayed between 33°C and 34°C (target 33.5°C) during maintenance of hypothermia. Cohorts had similar birth weight, gestational age, and level of encephalopathy at the initiation of therapy. Baseline esophageal temperature differed between groups (36.6°C ± 1.0°C for B2 vs. 33.9°C ± 1.2°C for B3, p<0.0001) reflecting the practice of passive cooling during transport prior to initiation of active device cooling in the B3 cohort. This difference prevented comparison of temperatures during induction of hypothermia. During maintenance of hypothermia the mean and standard deviation of the percent time between 33°C and 34°C was similar for B2 compared to B3 cohorts (94.8% ± 0.1% vs. 95.8% ± 0.1%, respectively). Both the automatic and gradient control modes of the Blanketrol devices appear comparable in maintaining esophageal temperature within the target range during maintenance of therapeutic hypothermia. PMID:25285767

  5. Fundamental investigation of high temperature operation of field effect transistor devices

    NASA Astrophysics Data System (ADS)

    Chern, Jehn-Huar

    In this dissertation copper germanium (CuGe)-based materials were investigated as potential ohmic contacts to n-type gallium arsenide (GaAs). The CuGe-based contacts to GaAs were found to not form any reaction products with GaAs and to have low contact resistance comparable to that of nickel gold germanium (NiAuGe) ohmic contacts to GaAs. The potential for high temperature applications using CuGe ohmic contacts was investigated. A guideline for further reduction of the contact resistance has been achieved after investigating the detailed mechanism of the formation of binary CuGe contacts over a wide range of Ge concentrations. The thermal stability of CuGe contacts was significantly enhanced and improved by introducing a diffusion barrier, titanium tungsten nitride (TiWNx), and a gold (Au) overlayer for high temperature applications. Novel approaches such as epitaxial thulium phosphide (TmP) Schottky contacts and the utilization of low temperature (LT)-aluminum gallium arsenide (AlGaAs) were also investigated in this dissertation and likely will be the standard technologies for a new generation of high-temperature electronics. Inserting a layer of aluminum arsenide (AlAs) underneath the channel of a GaAs-based MESFET was found to reduce substrate leakage currents by a factor of 30 compared with the same MESFET directly fabricated on a semi-insulating GaAs substrate. In addition to AlAs, and AlxGa1-xAs materials, new materials grown at low temperatures such as LT-AlGaAs were used in heterojunction FET structures as a back wall barrier. Low drain leakage currents were achieved using AlAs and LT-AlGaAs as the back wall barriers. Some fundamental properties regarding these materials are of great interest and in need of further characterization. Part of the work in this dissertation was devoted to the characterization of device performance for different structure designs at elevated temperatures. The suitability of GaAs-based and gallium arsenide (GaN)-based MESFET, JFET, pseudomorphic-HEMT, and modulation doped FET (MODFET) devices for high-temperature applications were investigated and addressed in terms of device performance such as transconductance, leakage current density, and current gain. Wide gap materials such as GaN have low carrier generation rate at high temperatures and, hence, high operation temperature capabilities and potential.

  6. Contact Thermocouple Methodology and Evaluation for Temperature Measurement in the Laboratory

    NASA Technical Reports Server (NTRS)

    Brewer, Ethan J.; Pawlik, Ralph J.; Krause, David L.

    2013-01-01

    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.

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

    SciTech Connect

    Not Available

    2011-11-01

    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.

  8. Thermoacoustic measurement of the temperature during microwave thermotherapy

    Microsoft Academic Search

    Cunguang Lou; Da Xing; Liming Nie

    2009-01-01

    Microwave thermotherapy (MT) has been an important treatment in oncology. The measurement of temperature during microwave thermotherapy is vital to ensure the safety of normal tissues. Thermoacoustic signals induced are temperature dependent. This phenomenon demonstrates that the thermal parameters are closely related to the generation of thermoacoustic pressure. Here we present the studies on pulsed microwave-induced thermoacoustic signals toward temperature

  9. Transient Temperature Measurement of Unburned Gas Using Optic Heterodyne Interferometry

    Microsoft Academic Search

    N. Kawahara; E. Tomita; H. Kamakura

    Optical heterodyne interferometry was validated to measure the transient temperature of a gas by comparing the temperature history of unburned gas in a combustion chamber, caused by compression due to flame propagation , obtained by the heterodyne interferometry wi th temperature obtained by assuming adiabatic change. When the density of gas changes, the effective optical path length of the test

  10. High resolution direct measurement of temperature distribution in silicon

    E-print Network

    Levy, Uriel

    , The Benin School of Engineering and Computer Science, The Center for Nanoscience and Nanotechnology the approach of Scanning Thermal Microscopy (SThM) to obtain an image of the temperature field of a silicon is measured locally and directly using a temperature sensitive AFM probe. We show that this local temperature

  11. Entropyenthalpy compensation as deduced from measurements of temperature dependence

    E-print Network

    Entropy­enthalpy compensation as deduced from measurements of temperature dependence Athel Cornish for a series of sample of the same enzyme from different sources, the variations in enthalpies of activation at a temperature known as the compensation temperature. Until recently, the evidence for this phenomenon came

  12. Final Report on the Measurement of the temperature of the

    E-print Network

    Final Report on the Measurement of the temperature of the Cosmic Microwave Background Toward investigations of the temperature of the cosmic microwave background using the apparatus developed and electrons, about 3000 K. Before this time / temperature, any neutral atoms formed could immediately be re

  13. Open circuit voltage temperature coefficients vs. concentration: Theory, indoor measurements, and outdoor measurements

    NASA Astrophysics Data System (ADS)

    Bagienski, Will; Kinsey, Geoffrey S.; Liu, Mingguo; Nayak, Adi; Garboushian, Vahan

    2012-10-01

    Current-voltage characteristics of multijunction III-V solar cells from several different vendors were measured at different light concentrations and temperatures. Measurements were taken indoors using flash lamp solar simulators and outdoors under natural sunlight. The change in open-circuit voltage with temperature was measured. Modeled results, indoor measurements, and outdoor measurements are compared.

  14. CARS Temperature Measurements in Turbulent and Supersonic Facilities

    NASA Technical Reports Server (NTRS)

    Jarrett, O., Jr.; Antcliff, R. R.; Smith, M. W.; Cutler, A. D.; Diskin, G. S.; Northam, G. B.

    1991-01-01

    This paper documents the development of the National Aeronautics and Space Administration s (NASA) Langley Research Center ( LaRC) Coherent Antistokes Raman Spectroscopy (CARS) systems for measurements of temperature in a turbulent subsonic or supersonic reacting hydrogen-air environment. Spectra data provides temperature data when compared to a precalculated library of nitrogen CARS spectra. Library validity was confirmed by comparing CARS temperatures derived through the library with three different techniques for determination of the temperature in hydrogen-air combustion and an electrically heated furnace. The CARS system has been used to survey temperature profiles in the simulated flow of a supersonic combustion ramjet (scramjet) model. Measurement results will be discussed.

  15. Liquid Oxygen Liquid Acquisition Device Bubble Point Tests with High Pressure LOX at Elevated Temperatures

    NASA Technical Reports Server (NTRS)

    Jurns, John M.; Hartwig, Jason W.

    2011-01-01

    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.

  16. Measurements of electrode temperature evolution by laser light reflection

    NASA Astrophysics Data System (ADS)

    Kempkens, H.; Byszewski, W. W.; Gregor, P. D.; Lapatovich, W. P.

    1990-04-01

    The electrode temperature rise during the starting of an arc discharge lamp has been measured using the temperature-dependent reflection coefficient of He-Ne laser light from metal surfaces. Lock-in techniques permit temporal resolution of about 3 ms, which is adequate to resolve 60-Hz phenomena such as electrode heating during the ac cycle. Calibration curves obtained by pyrometric measurements of constant-current tungsten ribbon lamps were used to relate the observed signal during electrode heating to its temperature. The technique described affords a nonintrusive method for measuring transient electrode temperature in an optically clustered environment with an accuracy of about 20%.

  17. Temperature measurement of fine wires by photothermal radiometry

    Microsoft Academic Search

    T. Borca-Tasciuc; G. Chen

    1997-01-01

    Wire drawing is a common industrial process and in situ temperature measurement techniques can be used for the quality control of the process. The temperature measurement of wire-type materials, however, is not easy because of ~1! the small diameter of the wire and ~2! the wire motion and vibration during the drawing process. Due to the motion of the wire,

  18. Non-contact temperature measurement requirements for electronic materials processing

    NASA Technical Reports Server (NTRS)

    Lehoczky, S. L.; Szofran, F. R.

    1988-01-01

    The requirements for non-contact temperature measurement capabilities for electronic materials processing in space are assessed. Non-contact methods are probably incapable of sufficient accuracy for the actual absolute measurement of temperatures in most such applications but would be useful for imaging in some applications.

  19. Digital holographic interferometry for measurement of temperature in axisymmetric flames.

    PubMed

    Sharma, Shobhna; Sheoran, Gyanendra; Shakher, Chandra

    2012-06-01

    In this paper, experimental investigations and analysis is presented to measure the temperature and temperature profile of gaseous flames using lensless Fourier transform digital holographic interferometry. The evaluations of the experimental results give the accuracy, sensitivity, spatial resolution, and range of measurements to be well within the experimental limits. Details of the experimental results and analysis are presented. PMID:22695554

  20. Temperature Measurements from Oxygen Isotope Ratios of Fish Otoliths

    Microsoft Academic Search

    Ian Devereux

    1967-01-01

    Measurements have shown that the temperature of a fish's habitat can be deduced from the oxygen isotope ratio of its otoliths (ear bones). Isotope ratios obtained from fossil otoliths indicate a water temperature which agrees with that found by isotope measurements on associated benthonic foraminifera.

  1. Temperature measurements from oxygen isotope ratios of fish otoliths.

    PubMed

    Devereux, I

    1967-03-31

    Measurements have shown that the temperature of a fish's habitat can be deduced from the Oxygen isotope ratio of its otoliths (ear bones). Isotope ratios Obtained from fossil otoliths indicate a water temperature which agrees wiht that found by isotope measurements on associated benthonic foraminifera. PMID:6020293

  2. Measurement of MTF Target Plasma Temperature Using Filtered Silicon Photodiodes

    E-print Network

    Measurement of MTF Target Plasma Temperature Using Filtered Silicon Photodiodes Presented at the 40* Los Alamos National Laboratory *Massey University, Auckland, New Zealand #12;Measurement of MTF Target Plasma Temperature Using Filtered Silicon Photodiodes Magnetized Target Fusion (MTF) is an approach

  3. Superheterodyne radiometer to measure electron temperature profile in Aditya tokamak

    Microsoft Academic Search

    Neelima Chaube; K. K Jain

    1997-01-01

    Among the coherent, and incoherent radiations emanating out of the tokamak plasmas, the latter gives vital information about the electron temperature. Electron cyclotron emission (ECE) is a powerful diagnostic tool for the measurement of electron temperature in tokamak plasma. In this paper, we present the design of the microwave superheterodyne radiometer to make spectrally resolved measurements of the ECE in

  4. Measurement of Alpha Particle Radioactivtiy in IC Device Packages

    Microsoft Academic Search

    E. S. Meieran; P. R. Engel; T. C. May

    1979-01-01

    Alpha particle radioactivity in package materials has been shown to cause soft errors in semiconductor devices. The particles are emitted by uranium and thorium decay sequence radioactive isotopes present as trace impurities in the raw materials used to make the package component parts. Chemical and radiation analys s techniques were correlated to alpha particle fluxes, which range in value from

  5. Interference Analysis of Infrared Temperature Measurement in Hybrid Welding

    Microsoft Academic Search

    Jifeng Wang; Houde Yu; Yaozhou Qian; Rongzun Yang

    \\u000a Welding is an essential thermal processing and a thermal conducting, so infrared sensing is a natural choice for weld process\\u000a monitoring to measure and control temperature. However, the infrared temperature is interfered because of radiation reflection\\u000a during applying IR sensing to the welding. The objective of this research is to measure the top-face temperature distribution\\u000a in hybrid laser-TIG welding process.

  6. Low temperature processed complementary metal oxide semiconductor (CMOS) device by oxidation effect from capping layer.

    PubMed

    Wang, Zhenwei; Al-Jawhari, Hala A; Nayak, Pradipta K; Caraveo-Frescas, J A; Wei, Nini; Hedhili, M N; Alshareef, H N

    2015-01-01

    In this report, both p- and n-type tin oxide thin-film transistors (TFTs) were simultaneously achieved using single-step deposition of the tin oxide channel layer. The tuning of charge carrier polarity in the tin oxide channel is achieved by selectively depositing a copper oxide capping layer on top of tin oxide, which serves as an oxygen source, providing additional oxygen to form an n-type tin dioxide phase. The oxidation process can be realized by annealing at temperature as low as 190 °C in air, which is significantly lower than the temperature generally required to form tin dioxide. Based on this approach, CMOS inverters based entirely on tin oxide TFTs were fabricated. Our method provides a solution to lower the process temperature for tin dioxide phase, which facilitates the application of this transparent oxide semiconductor in emerging electronic devices field. PMID:25892711

  7. Radiation thermometry applied to temperature measurement in the cutting process

    NASA Astrophysics Data System (ADS)

    Pujana, J.; del Campo, L.; Pérez-Sáez, R. B.; Tello, M. J.; Gallego, I.; Arrazola, P. J.

    2007-11-01

    Temperature measurement of cutting tools used in machining processes has great technological importance, and it is interesting in a large number of industrial applications because wear is directly related to this variable. The influence of emissivity on the temperature measurement using radiation thermometers and the dependence of the measured temperature on the emissivity as a function of the surface roughness and the oxidation state is studied in this paper. Emissivity is measured using the direct radiometric method for uncoated P10 tungsten carbide inserts. Theoretical temperature shifts produced by changes in emissivity are estimated for several types of radiation thermometers, and these shifts are compared to the experimental temperature measurements carried out in the orthogonal turning process of cylindrical samples of 42CrMo4 steel with different machinability grades.

  8. Temperature dependent E and G measurement of materials using ultrasonic guided waves

    NASA Astrophysics Data System (ADS)

    Periyannan, Suresh; Balasubramaniam, Krishnan

    2014-02-01

    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.

  9. Specific cell capture and temperature-mediated release using surface-immobilized aptamers in a microfluidic device

    Microsoft Academic Search

    Jing Zhu; ThaiHuu Nguyen; Renjun Pei; Milan Stojanovic; Qiao Lin

    2011-01-01

    We present a microfluidic device with an integrated temperature sensor and heaters for capture as well as subsequent temperature mediated release and recovery of CCRF-CEM cells. Specific cell capture is achieved by a surface immobilized aptamer. A moderate temperature change is then introduced to disrupt the cell-aptamer interaction, allowing the release of captured cells from the aptamer modified surface and

  10. 48 IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 49, NO. 1, JANUARY 2002 Temperature Behavior of Visible and Infrared

    E-print Network

    Steckl, Andrew J.

    Terms--Electroluminescence, Er, GaN, ITO, temperature dependence. I. INTRODUCTION RARE-EARTH doped photo-, cathodo-, and electrolu- minescence studies [11]. The temperature dependence of IR ra- diation48 IEEE TRANSACTIONS ON ELECTRON DEVICES, VOL. 49, NO. 1, JANUARY 2002 Temperature Behavior

  11. Use of the Phenomenon of High-Temperature Superconductivity for the Creation of Integrated Devices of Microwave Electronics

    Microsoft Academic Search

    A. A. Dymnikov; O. D. Poustylnik

    1999-01-01

    Physical fundamentals justifying the use of integrated microwave circuits based on films of high-temperature superconductors in microwave electronics are presented. The peculiarities of calculations of high-temperature superconducting film microwave elements are shown. The technological conditions of the creation of integrated microwave devices based high-temperature superconducting on films are analyzed.

  12. Surveying Temperature and Density Measurements in Nuclear Calorimetry

    NASA Astrophysics Data System (ADS)

    Raciti, G.; Bassini, R.; Begemann-Blaich, M.; Fritz, S.; Groß, C.; Immè, G.; Iori, I.; Lynen, U.; Mahi, M.; Möhlenkamp, T.; Müller, W. F. J.; Ocker, B.; Odeh, T.; Pochodzalla, J.; Riccobene, G.; Romano, F. P.; Saija, A.; Schwarz, C.; Serfling, V.; Schnittker, M.; Schüttauf, A.; Seidel, W.; Sfienti, C.; Trautmann, W.; Trzclnski, A.; Verde, G.; Xi, Hongfei; Zwieglinski, B.

    2001-11-01

    An experimental investigation on thermodynamical observables characterizing the conditions of multifragmenting systems is reported. High granularity hodoscopes allowed simultaneous measurements of isotopic and emission temperatures. HBT interferometry with light charged particles allowed radii measurements. The disagreement between the two temperature measurements could be related to the space-time evolution of the fragmentation process as confirmed by density measurements. The slope temperatures derived from the target spectator decay fragment energy spectra suggest a dependence on the Fermi motion within the initial system. The dependence of the Nuclear Caloric Curve on the mass of the systems was probed.

  13. Solar energy control system. [temperature measurement

    NASA Technical Reports Server (NTRS)

    Currie, J. R. (inventor)

    1981-01-01

    A solar energy control system for a hot air type solar energy heating system wherein thermocouples are arranged to sense the temperature of a solar collector, a space to be heated, and a top and bottom of a heat storage unit is disclosed. Pertinent thermocouples are differentially connected together, and these are employed to effect the operation of dampers, a fan, and an auxiliary heat source. In accomplishing this, the differential outputs from the thermocouples are amplified by a single amplifier by multiplexing techniques. Additionally, the amplifier is corrected as to offset by including as one multiplex channel a common reference signal.

  14. Stand Alone Pressure Measurement Device (SAPMD) for the space shuttle Orbiter, part 1

    NASA Technical Reports Server (NTRS)

    Tomlinson, Bill

    1989-01-01

    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.

  15. Bed conduction impact on fiber optic distributed temperature sensing water temperature measurements

    NASA Astrophysics Data System (ADS)

    O'Donnell Meininger, T.; Selker, J. S.

    2015-02-01

    Error in distributed temperature sensing (DTS) water temperature measurements may be introduced by contact of the fiber optic cable sensor with bed materials (e.g., seafloor, lakebed, streambed). Heat conduction from the bed materials can affect cable temperature and the resulting DTS measurements. In the Middle Fork John Day River, apparent water temperature measurements were influenced by cable sensor contact with aquatic vegetation and fine sediment bed materials. Affected cable segments measured a diurnal temperature range reduced by 10% and lagged by 20-40 min relative to that of ambient stream temperature. The diurnal temperature range deeper within the vegetation-sediment bed material was reduced 70% and lagged 240 min relative to ambient stream temperature. These site-specific results illustrate the potential magnitude of bed-conduction impacts with buried DTS measurements. Researchers who deploy DTS for water temperature monitoring should understand the importance of the environment into which the cable is placed on the range and phase of temperature measurements.

  16. Measurement of Thermal Conductivity Using Steady-State Isothermal Conditions and Validation by Comparison with Thermoelectric Device Performance

    NASA Astrophysics Data System (ADS)

    Taylor, Patrick J.; Maddux, Jay R.; Uppal, Parvez N.

    2012-09-01

    A new technique for measuring thermal conductivity with significantly improved accuracy is presented. By using the Peltier effect to counterbalance an imposed temperature difference, a completely isothermal, steady-state condition can be obtained across a sample. In this condition, extraneous parasitic heat flows that would otherwise cause error can be eliminated entirely. The technique is used to determine the thermal conductivity of p-type and n-type samples of (Bi,Sb)2(Te,Se)3 materials, and thermal conductivity values of 1.47 W/m K and 1.48 W/m K are obtained respectively. To validate this technique, those samples were assembled into a Peltier cooling device. The agreement between the Seebeck coefficient measured individually and from the assembled device were within 0.5%, and the corresponding thermal conductivity was consistent with the individual measurements with less than 2% error.

  17. Filtering and Temperature Correction Algorithms for Smog Interference in Temperature Measurement Based on CCD Image Sensor

    Microsoft Academic Search

    Xiaoqi Peng; Yuan Sun

    2009-01-01

    The visible radiation would be absorbed and scattered by the smog diffusing around the radiator and on the path of the radiation, which distorts the results of temperature measurement by two-color thermometry based on CCD image sensor. In this paper, an approach for filtering smog interference of high-temperature radiator and correcting temperature is proposed. Firstly, by the image target recognition

  18. BRAIN TEMPERATURE MEASUREMENT IN RATS: A COMPARISON OF MICROWAVE AND AMBIENT TEMPERATURE EXPOSURES

    EPA Science Inventory

    The brain and core temperatures of rats and rat carcasses exposed to microwave radiation (2450 MHz) or elevated air temperatures were measured in two studies. In general, no substantial evidence for temperature differentials, or hot spots, in the brain of these animals was found....

  19. Improvised explosive device (IED) counter-measures in Iraq

    Microsoft Academic Search

    J. Ziegler

    2009-01-01

    Summary form only given: Land mines have been used in warfare since the 13l century. Their greatest weakness has always been to coordinate the timing of the explosion with an enemy's movement. improvised explosive devices (IED's) are mines that are constructed in the field using available munitions. In the 16th century these were detonated using a clock-timer or concealed trip-wire.

  20. High temperature permeameter for measuring magnetic properties

    NASA Technical Reports Server (NTRS)

    Barranger, J. P.

    1972-01-01

    Instrument for measuring magnetic permeability of materials undergoing heat treatment as method for monitoring stress relief and tempering is described. Procedure is based on magnetic potentiometer principle with yoke compensating coils to cancel effects of reluctance of yoke and joint gaps. Instrument is heated with specimen being heat treated.

  1. NMR measurement of bitumen at different temperatures

    Microsoft Academic Search

    Zheng Yang; George J. Hirasaki

    2008-01-01

    Heavy oil (bitumen) is characterized by its high viscosity and density, which is a major obstacle to both well logging and recovery. Due to the lost information of T2 relaxation time shorter than echo spacing (TE) and interference of water signal, estimation of heavy oil properties from NMR T2 measurements is usually problematic. In this work, a new method has

  2. Temperature measurements at IODP 337 Expedition, off Shimokita, NE Japan.

    NASA Astrophysics Data System (ADS)

    Yamada, Y.; Sanada, Y.; Moe, K.; Kubo, Y.; Inagaki, F.

    2014-12-01

    Precise estimation of underground temperature is a challenging issue, since direct measurements require drill holes that disturb the original underground environment. During IODP 337 expedition, we have obtained in-situ temperature datasets for several times by using geophysical logging tools. A common procedure to estimate the undisturbed maximum underground temperature is by approximating that the 'build-up' pattern of measured values in the borehole should reach to the equilibrium temperature. At the Shimokita site, this was 63.7 oC at a depth of 2466 m. We have much more measurement dataset and all of these were used to analyze detailed in-site temperatures at various depths. The result shows a non-linear temperature profile to the depth and this may be reflected by the thermal properties of the surrounding rocks.

  3. Temperature measurement method using temperature coefficient timing for resistive or capacitive sensors

    DOEpatents

    Britton, Jr., Charles L. (Alcoa, TN); Ericson, M. Nance (Knoxville, TN)

    1999-01-01

    A method and apparatus for temperature measurement especially suited for low cost, low power, moderate accuracy implementation. It uses a sensor whose resistance varies in a known manner, either linearly or nonlinearly, with temperature, and produces a digital output which is proportional to the temperature of the sensor. The method is based on performing a zero-crossing time measurement of a step input signal that is double differentiated using two differentiators functioning as respective first and second time constants; one temperature stable, and the other varying with the sensor temperature.

  4. New methods for magnetic susceptibility measurements of solid 3 He at ultralow temperatures

    Microsoft Academic Search

    H. Yano; T. Uchiyama; T. Kato; Y. Minamide; S. Inoue; Y. Miura; T. Mamiya

    1990-01-01

    An ac mutual inductance bridge for magnetic susceptibility measurements of solid3He in a metallic cell at ultralow temperatures is described. A null detector for the bridge was composed of an rf-biased superconducting quantum interference device (rf-SQUID) system and a lock-in amplifier that avoided strong fields of the nuclear demagnetization magnets. A design of a sample cell to reduce eddy currents

  5. High temperature rectifiers and MOS devices in 6H-silicon carbide

    NASA Astrophysics Data System (ADS)

    Palmour, J. W.; Edmond, J. A.; Carter, C. H., Jr.

    1992-04-01

    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 igniter circuit. The developments required involved decreasing the doping level of the background layer in epitaxial growth, improving the passivation and packaging to withstand the high voltage and high temperature. The other is a 350 deg C small signal MOSFET which can be used as an amplifier for a variety of sensors. For this portion of the research, the major focus was on characterization of the thermal oxide and the oxide interface through fabrication and characterization of MOS capacitors and various MOSFET designs.

  6. High-temperature deformation field measurement by combining transient aerodynamic heating simulation system and reliability-guided digital image correlation

    Microsoft Academic Search

    Bing Pan; Dafang Wu; Yong Xia

    2010-01-01

    To determine the full-field high-temperature thermal deformation of the structural materials used in high-speed aerospace flight vehicles, a novel non-contact high-temperature deformation measurement system is established by combining transient aerodynamic heating simulation device with the reliability-guided digital image correlation (RG-DIC). The test planar sample with size varying from several mm2 to several hundreds mm2 can be heated from room temperature

  7. Temperature dependence of conductivity measurement for conducting polymer

    NASA Astrophysics Data System (ADS)

    Gutierrez, Leandro; Duran, Jesus; Isah, Anne; Albers, Patrick; McDougall, Michael; Wang, Weining

    2014-03-01

    Conducting polymer-based solar cells are the newest generation solar cells. While research on this area has been progressing, the efficiency is still low because certain important parameters of the solar cell are still not well understood. It is of interest to study the temperature dependence of the solar cell parameters, such as conductivity of the polymer, open circuit voltage, and reverse saturation current to gain a better understanding on the solar cells. In this work, we report our temperature dependence of conductivity measurement using our in-house temperature-varying apparatus. In this project, we designed and built a temperature varying apparatus using a thermoelectric cooler module which gives enough temperature range as we need and costs much less than a cryostat. The set-up of the apparatus will be discussed. Temperature dependence of conductivity measurements for PEDOT:PSS films with different room-temperature conductivity will be compared and discussed. NJSGC-NASA Fellowship grant

  8. A convenient on-line device for reagent addition, sample mixing, and temperature control of cell suspensions in flow cytometry.

    PubMed

    Omann, G M; Coppersmith, W; Finney, D A; Sklar, L A

    1985-01-01

    We describe a simple and inexpensive device which permits the addition of up to three different solutions into a cell suspension which is on-line in a flow cytometer. The mixing chamber houses a disposable plastic cuvette stirred with a magnetic stirrer. The sample chamber is attached to a circulating water bath, hence accurate temperature control is achieved. Because the system is prepressurized and the sample line is very short, the delay time-between the point of sample modification and the point of analysis is reduced to a few seconds. Thus reagents may be added rapidly, and kinetic measurements of high temporal resolution are possible. Because the temperature of the sample chamber is regulated, binding can be observed over longer time periods than was previously possible. We demonstrate the usefulness of this device in determining the binding of fluoresceinated hexapeptide to human neutrophils under conditions where the stimulus is infused into the cell suspension while on-line in the cytometer. PMID:3967555

  9. Advances in the crystal growth and device fabrication technology of CdZnTe room temperature radiation detectors

    Microsoft Academic Search

    Csaba Szeles

    2004-01-01

    The performance of CdZnTe room-temperature X-ray and gamma-ray detectors is determined by material and device defects that govern carrier transport trough the device. In this contribution, we review common bulk, interface, and surface defects and their effects on charge transport, charge transport uniformity, and device performance. We note that pure CdZnTe grown under Te-rich conditions has an excess of Cd-vacancies

  10. Influence of ambient temperature on whole body and segmental bioimpedance spectroscopy measurements

    NASA Astrophysics Data System (ADS)

    Medrano, G.; Bausch, R.; Ismail, A. H.; Cordes, A.; Pikkemaat, R.; Leonhardt, S.

    2010-04-01

    Bioimpedance spectroscopy (BIS) measurements are easy to implement and could be used for continuous monitoring. However, several factors (e.g. environment temperature) influence the measurements limiting the accuracy of the technology. Changes in skin temperature produced by changes in ambient temperature are related with changes in skin blood flow and skin impedance. It is assumed that skin impedance change is responsible for the error observed in whole body and segmental measurements. Measurements including body parts more distant from the torso seem to be more affected. In the present article skin and segment impedance have been performed on healthy subjects under extreme changes in environment temperature (13-39 °C). A commercial BIS device with a range between 5 kHz and 1 MHz has been used for the measurements. The results indicate that not only skin impedance, but also impedance of deeper tissue (e.g. muscle) may be responsible for the influence of environment temperature on BIS measurements. Segmental (knee-to-knee) BIS measurements show a relative change of only 2 %, while forearm and whole body impedance changed 14 % and 8 % respectively.

  11. Devices and Methods for Maintenance of Temperature and Pressure During Islet Shipment

    PubMed Central

    Rozak, P.R.; Weegman, B.P.; Avgoustiniatos, E.S.; Wilson, J.R.; Welch, D.P.; Hering, B.J.; Papas, K.K.

    2009-01-01

    Exposure to extreme temperatures and pressure fluctuations during shipment by air may have a detrimental impact on islet quality. In this study, we sought to assess the ability of methods and devices to provide better control of the internal environment of islet shipping containers in terms of temperature and pressure. Methods Experimental islet shipping containers were packed with 21 panels of commercially available TCP Phase 22 Phase Change Material (TCP). The containers were then exposed for at least 15 hours to three constant external temperature conditions, namely, ?20°C, 4°C, and 40°C, and then evaluated for their ability to maintain an internal temperature close to the desired value of 22°C. Custom-designed pressure regulated gyroscopic shipping containers (PRGSC) placed in a vacuum chamber were exposed to an absolute pressure of 250 mm Hg (substantially lower than that experienced during shipment by air) for 25 minutes to assess their ability to control internal pressure under vacuum. Electronic data loggers were used to monitor internal and external temperatures and pressures under all conditions. Results Twenty-one TCP panels placed in a single islet shipping container were able to maintain the internal temperature between 17°C and 24°C for a minimum of 15 hours at all three external temperatures. The PRGSC tested were able to maintain a constant internal pressure of 760 mm Hg when exposed to vacuum. Conclusions Our results demonstrated that the use of containers equipped with TCP and PRGSC exert excellent environmental control over islet shipments by minimizing temperature and eliminating pressure fluctuations. PMID:18374083

  12. Measuring Temperature and its Effect on Water Quality

    NSDL National Science Digital Library

    Larry Johnson

    This module on measuring temperature and its effects on water quality is from a larger series on water quality investigations. The purpose of the site is to help students recognize that temperature can affect the organisms that live in water, describe the factors that can change the temperature of a body of water, and how to measure, graph, and interpret the effects of temperature on fish. It provides background information, a pre-test and post-test, a laboratory investigation, and a self-study game.

  13. Application of phosphor thermometry to a Galvanneal Temperature Measurement System

    SciTech Connect

    Allison, S.W.; Andrews, W.H.; Beshears, D.L.; Cates, M.R.; Childs, R.M.; Grann, E.B.; Manges, W.W.; McIntyre, T.J.; Scudiere, M.B.; Simpson, M.L.

    1999-08-22

    The Galvanneal Temperature Measurement System (GTMS) was developed for the American Iron and Steel Institute by the Oak Ridge National Laboratory through a partnership with the National Steel Midwest Division in Portage, Indiana. The GTMS provides crucial on-line thermal process control information during the manufacturing of galvanneal steel. The system has been used with the induction furnaces to measure temperatures ranging from 450 to 700 degrees C with an accuracy of better than +/-5 Degrees C. The GTMS provides accurate, reliable temperature information thus ensuring a high quality product, reducing waste, and saving energy. The production of uniform, high-quality galvanneal steel is only possible through strict temperature control.

  14. A REAL-TIME MEASURING DEVICE FOR DENSE PARTICULATE SYSTEMS

    EPA Science Inventory

    The report describes the design and performance of an instrument, based on the concept of instantaneous intensity ratio, for measuring particle size distributions of dense particulate matter. The method involves simultaneously measuring the intensity of light scattered by a parti...

  15. Measurement and device design of left-handed metamaterials

    E-print Network

    Thomas Zachary M. (Zachary Michael)

    2005-01-01

    The properties of a variety of left-handed metamaterial (LHM) structures are analyzed and measured to verify consistent behavior between theory an measurements. The structures are simulated using a commercial software ...

  16. Use of Novel Ceramic-Metal Braze for Joining in High Temperature Electrochemical Devices

    SciTech Connect

    Weil, K. Scott; Hardy, John S.; Kim, Jin Yong Y.

    2003-09-15

    One of the challenges in manufacturing solid-state electrochemical devices, such as planar solid oxide fuel cells (pSOFC) and oxygen generators, is in hermetically sealing the ceramic and metallic components such that the resulting joint remains rugged and stable under continuous high temperature operation in an oxidizing atmosphere. A well proven method of joining dissimilar materials is by brazing. Unfortunately many of the commercially available ceramic-to-metal braze alloys exhibit oxidation properties which are unacceptable for use in these applications. This paper outlines an alternative brazing technique that is being developed specifically for use in an oxidizing environment.

  17. Very sensitive measurement method of electron devices current noise

    Microsoft Academic Search

    M. Macucci; B. Pellegrini

    1991-01-01

    The problem of measuring very low levels of current noise in bipoles (linear or not) is dealt with, and a measurement technique is proposed. This technique allows the measurement of noise power spectra 6-10 dB lower than the equivalent input power spectrum of the amplified necessary to perform the measurement. An improvement of 16-20 dB in the sensitivity is obtained

  18. Metrological verification of FPGA based device for measuring EEG signal

    Microsoft Academic Search

    Platon Sovilj; V. Vujic?ic?; N. Pjevalica

    2010-01-01

    The paper presents a field-programmable gate array (FPGA) based model for measurement of electroencephalography (EEG) signal. The novelty of this system is implementation of digital stochastic block based on stochastic analog-to-digital (A\\/D) conversion and accumulation, with a novel hardware structure tailored for harmonic measurements. Metrologically verified stochastic measurement EEG system measured DC component of the signal and 15 harmonics with

  19. Measuring the Verdet constant: a simple, high precision, automatic device

    Microsoft Academic Search

    O. Brevet-Philibert; R. Brunetton; J. Monin

    1988-01-01

    An instrument is described that allows the automatic measurement of the Verdet constant. The measuring cell, especially suited for liquids, is of original design. Using a multipass of the light beam, it provides high Faraday rotation with a low magnetic field. The rotation of the polarisation is measured automatically by a novel technique. Systematic errors are very small and the

  20. Synthesis of agar microparticles using temperature-controlled microfluidic devices for Cordyceps militaris cultivation.

    PubMed

    Lin, Yung-Sheng; Yang, Chih-Hui; Lu, Kang; Huang, Keng-Shiang; Zheng, Ying-Zhen

    2011-11-01

    A temperature-controlled microfluidic approach was developed for fabricating monodispersed agar beads with the potential to be a brand-new strategy for cultivating Cordyceps militaris. The proposed microfluidic system features a circulating water bath with precise temperature control (temperature deviation ?T<0.1°C). This device holds the promise of allowing us to develop a temperature-controlled system, characterized as simple, low cost, and easy to set up and use. The size-controllable agar beads were achieved by utilizing microfluidic emulsification in the cross-junction channel under temperature-controlled conditions. The flow conditions of the dispersed/continuous phases were adjusted to generate various sizes of agar beads. Our results show that the microparticles produced are as small as 176 ??m with a 95% particle size distribution within 5? ?m. The prepared agar microparticles performed well as a substrate for the cultivation of C. militaris. The proposed method could also be applied for encapsulating biomaterials, enzymes, drugs, catalysts, and nanoparticles into agar beads for biomedical applications. PMID:22012813

  1. Calibration accuracy of hospital-based non-invasive blood pressure measuring devices

    Microsoft Academic Search

    A de Greeff; I Lorde; A Wilton; P Seed; A J Coleman; A H Shennan; AH Shennan

    2010-01-01

    Accurate blood pressure (BP) measurement is dependent on a trained observer using validated and properly maintained equipment. BP devices should be checked regularly to ensure that their calibration remains within the European Standard specification of ±3 mm Hg. This study assessed the air leakage rates and calibration accuracy of BP devices in use at a large teaching hospital, using a

  2. Measuring surface vibrations of musical instruments using an inexpensive digital holography device

    Microsoft Academic Search

    Nazif Demoli; Ivan Demoli

    2005-01-01

    A new device for measuring surface vibrations of musical instruments is presented. The architecture of the device is based on a quasi-Fourier digital holography setup with inexpensive commercial elements capable of recording large digital holograms. Experimental results showing vibration modes for several musical instruments are given. The results demonstrate fringe pattern quality as well as the testing possibilities in tuning

  3. A new device for measuring fluctuations in plant stem diameter: Implications for monitoring plant responses

    Microsoft Academic Search

    Peter A. Beedlow; Don S. Daly; Michael E. Thiede

    1986-01-01

    An electrical device capable of continuously measuring micronsized changes in stem diameter of woody and herbaceous plants is described. Fumigation of sunflowers with automotive exhaust was used to test the ability of the device to detect short-term plant responses.

  4. A complex of navigational-measurement and observational devices for manned spacecraft

    Microsoft Academic Search

    I. A. Zabelina

    2006-01-01

    This paper discusses a complex of navigational-measurement and observational devices for manned space ships (MSSs), space stations (SSs), and the Buran reusable space system. The problems that arise in creating visual optical devices (VODs) are analyzed. The main technical requirements on the portholes and the glazing of the helmets of space suits as a component of VODs are considered. In

  5. A Precise Calibration Technique for Measuring High Gas Temperatures

    NASA Technical Reports Server (NTRS)

    Gokoglu, Suleyman A.; Schultz, Donald F.

    2000-01-01

    A technique was developed for direct measurement of gas temperatures in the range of 2050 K 2700 K with improved accuracy and reproducibility. The technique utilized the low-emittance of certain fibrous materials, and the uncertainty of the technique was United by the uncertainty in the melting points of the materials, i.e., +/-15 K. The materials were pure, thin, metal-oxide fibers whose diameters varied from 60 microns to 400 microns in the experiments. The sharp increase in the emittance of the fibers upon melting was utilized as indication of reaching a known gas temperature. The accuracy of the technique was confirmed by both calculated low emittance values of transparent fibers, of order 0.01, up to a few degrees below their melting point and by the fiber-diameter independence of the results. This melting-point temperature was approached by increments not larger than 4 K, which was accomplished by controlled increases of reactant flow rates in hydrogen-air and/or hydrogen-oxygen flames. As examples of the applications of the technique, the gas-temperature measurements were used: (a) for assessing the uncertainty in inferring gas temperatures from thermocouple measurements, and (b) for calibrating an IR camera to measure gas temperatures. The technique offers an excellent calibration reference for other gas-temperature measurement methods to improve their accuracy and reliably extending their temperature range of applicability.

  6. A Precise Calibration Technique for Measuring High Gas Temperatures

    NASA Technical Reports Server (NTRS)

    Gokoglu, Suleyman A.; Schultz, Donald F.

    1999-01-01

    A technique was developed for direct measurement of gas temperatures in the range of 2050 K - 2700 K with improved accuracy and reproducibility. The technique utilized the low-emittance of certain fibrous Materials, and the uncertainty of the technique was limited by the uncertainty in the melting points of the materials, i.e., +/- 15 K. The materials were pure, thin, metal-oxide fibers whose diameters varied from 60 mm to 400 mm in the experiments. The sharp increase in the emittance of the fibers upon melting was utilized as indication of reaching a known gas temperature. The accuracy of the technique was confirmed by both calculated low emittance values of transparent fibers, of order 0.01, up to a few degrees below their melting point and by the fiber-diameter independence of the results. This melting-point temperature was approached by increments not larger than 4 K, which was accomplished by controlled increases of reactant flow rates in hydrogen-air and/or hydrogen- oxygen flames. As examples of the applications of the technique, the gas-temperature measurements were used (a) for assessing the uncertainty in infering gas temperatures from thermocouple measurements, and (b) for calibrating an IR camera to measure gas temperatures. The technique offers an excellent calibration reference for other gas-temperature measurement methods to improve their accuracy and reliably extending their temperature range of applicability.

  7. Ion and electron temperatures in the SUMMA mirror device by emission spectroscopy

    NASA Technical Reports Server (NTRS)

    Patch, R. W.; Voss, D. E.; Reinmann, J. J.; Snyder, A.

    1974-01-01

    Ion and electron temperatures, and ion drift were measured in a superconducting magnetic mirror apparatus by observing the Doppler-broadened charge-exchange component of the 667.8 and 587.6 nanometer He lines in He plasma, and the H sub alpha and H sub beta lines in H2 plasma. The second moment of the line profiles was used as the parameter for determining ion temperature. Corrections for magnetic splitting, fine structure, monochromator slit function, and variation in charge-exchange cross section with energy are included. Electron temperatures were measured by the line ratio method for the corona model, and correlations of ion and electron temperatures with plasma parameters are presented.

  8. Nano-superconducting quantum interference devices with continuous read out at milliKelvin temperatures

    NASA Astrophysics Data System (ADS)

    Hazra, D.; Kirtley, J. R.; Hasselbach, K.

    2013-08-01

    We describe aluminum-niobium-tungsten trilayer Nano-Superconducting Quantum Interference Devices (NanoSQUIDs) that can be read out continuously down, in temperature, to at least 230 mK. They show voltage oscillations up to at least 20 mT in field. A voltage modulation of 500 ?V, voltage sensitivity of 2 mV/?0, and white noise floor better than 5×10-5 ?0/?Hz have been obtained. Flux noise places them between conventional low impedance SQUIDs and standard nanoSQUIDs. High sensitivity and ease of implementation make this new kind of nanoSQUID attractive for magnetic detection schemes on the nanoscale and low temperature scanning SQUID microscopy.

  9. InAs quantum well Hall devices for room-temperature detection of single magnetic biomolecular labels.

    SciTech Connect

    Mihajlovic, G.; Xiong, P.; von Molnar, S.; Field, M.; Sullivan, G. J.; Materials Science Division; Florida State Univ.; Teledyne Scientific Co. LLC

    2007-08-01

    Hall sensors with cross width of {approx}1 {micro}m were fabricated from InAs/AlSb quantum well semiconductor heterostructures containing two-dimensional electron gas. The room-temperature device characteristics were examined by Hall effect and electronic noise measurements along with analytical calculations. In the low-frequency range, from 20 Hz to 1.6 kHz, the noise-equivalent magnetic field resolution was found to be limited by 1/f and generation-recombination noise from 22 to 3.5 {micro}T/{radical}Hz. The corresponding noise-equivalent magnetic moment resolution reached 10{sub {mu}{sub B}}{sup 6}/{radical}Hz at {approx}700 Hz and was even lower at higher frequencies. Using a phase-sensitive measurement technique, detection of a single 1.2 {micro}m diameter bead, suitable for biological applications, was achieved with a signal to noise ratio of {approx}33.3 dB, as well as detection of six 250 nm beads with a signal to noise of {approx}2.3 dB per bead. The work demonstrates the efficacy of InAs quantum well Hall devices for application in high sensitivity detection of single magnetic biomolecular labels.

  10. Formation of Electron Internal Transport Barrier and Achievement of High Ion Temperature in Large Helical Device

    NASA Astrophysics Data System (ADS)

    Takeiri, Yasuhiko

    2002-11-01

    Achievement of high-temperature plasmas is one of the main goals in the helical system because enhanced transport is predicted in the collisionless regime by the neoclassical theory without the radial electric field. In the Large Helical Device (LHD), when the centrally focused intense ECR microwave was superimposed on the NB-heated plasma, an internal transport barrier (ITB) was observed in the electron temperature profile, which shows a centrally peaked profile with a steep gradient inside r/a=0.4. The central electron temperature exceeded 10 keV in a collisionless regime, and a strong radial electric field was observed inside the electron ITB. There exist clear power and density thresholds for the ITB formation, where a reduction of the electron thermal diffusivity was recognized. The threshold temperature for the ITB formation depends on the electron density, and its dependency is consistent with the theoretically predicted one for the transition from the neoclassical ion root to electron root. The direction of the tangentially injected beam-driven current has an influence on the ITB formation. For the counter-injected target plasma, a steeper Te gradient, than that for the co-injected one, was observed. As for the ion temperature, high-power NBI heating of 9 MW has realized a central ion temperature of 5 keV with neon injection. Since the LHD-NBI system employs the negative hydrogen ions, the injection energy of which is as high as 160 keV, most of the NB power goes to electrons and the ion temperature was less than 3 keV in the hydrogen plasmas. By introducing the neon gas, the NB-absorption power was increased in low-density plasmas and the direct ion heating power was much enhanced with a reduced number of ions, compared with the hydrogen plasmas.

  11. Scanning optical pyrometer for measuring temperatures in hollow cathodes

    SciTech Connect

    Polk, J. E.; Marrese-Reading, C. M.; Thornber, B.; Dang, L.; Johnson, L. K.; Katz, I. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States); International Space University, 67000 Strasbourg (France); California Institute of Technology, Pasadena, California 91109 (United States); Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

    2007-09-15

    Life-limiting processes in hollow cathodes are determined largely by the temperature of the electron emitter. To support cathode life assessment, a noncontact temperature measurement technique which employs a stepper motor-driven fiber optic probe was developed. The probe is driven inside the hollow cathode and collects light radiated by the hot interior surface of the emitter. Ratio pyrometry is used to determine the axial temperature profile. Thermocouples on the orifice plate provide measurements of the external temperature during cathode operation and are used to calibrate the pyrometer system in situ with a small oven enclosing the externally heated cathode. The diagnostic method and initial measurements of the temperature distribution in a hollow cathode are discussed.

  12. Thermoacoustic measurement of the temperature during microwave thermotherapy

    NASA Astrophysics Data System (ADS)

    Lou, Cunguang; Xing, Da; Nie, Liming

    2009-08-01

    Microwave thermotherapy (MT) has been an important treatment in oncology. The measurement of temperature during microwave thermotherapy is vital to ensure the safety of normal tissues. Thermoacoustic signals induced are temperature dependent. This phenomenon demonstrates that the thermal parameters are closely related to the generation of thermoacoustic pressure. Here we present the studies on pulsed microwave-induced thermoacoustic signals toward temperature monitoring of tissue thermotherapy. A high power pulsed microwave was used as thermoacoustic excitation source and heating source simultaneously, thermoacoustic pressure was captured by a multi-element linear transducer array. Excellent agreement was obtained between the inversion calculation results and the actual measurement temperature. The results suggest that thermoacoustic signals can be used to monitor thermotherapy temperature, and has the potential of reconstruct the temperature distribution by filter back-projection algorithm. This method has a great potential to develop into an integrated system for pulsed microwave thermotherapy and curative effect monitoring.

  13. Low temperature hermetically sealed three-dimensional MEMS device for wireless optical communication

    NASA Astrophysics Data System (ADS)

    Agarwal, Rahul

    Novel processes were developed that resulted in a self-packaged device during the system integration, along with a transparent lid for inspection or optical probing. A new process was developed for improving the verticality in Micro Electro Mechanical Systems (MEMS) structures using Deep Reactive Ion Etching (DRIE). A self-pattered, mask-less photolithography technique was developed to metallize these vertical structures while maintaining a transparent window, for packaging of various MEMS devices. The verticality and metallization coverage were evaluated by incorporating the MEMS structures into an optical Corner Cube Retroreflector (CCR). A low temperature, hermetic sealing technique was also developed using In-Au thermo-compression bonding at 160°C. Cross-shaped 550microm deep vertical mirrors, with sidewall angles of 90.08° were etched with this new DRIE technique. This is the best reported sidewall angle for such deep structures. The typical scalloped DRIE sidewall roughness was reduced to 40nm using wet polishing. A bonded Pyrex wafer was used as the handle wafer during DRIE; it eventually forms the package window after DRIE. The metallized, vertical mirrors were bonded to a MEMS device chip to assemble and package the CCR. The MEMS device chip consisted of an array of torsion mirrors. The mirrors were designed to modulate at 6Vp-p--20V p-p, with the resonant frequencies ranging from 25 KHz--50 KHz. The design and simulation results are presented. To test the hermetic seal, helium leak tests were performed on the packaged device. Leak rates of as low as 2.8x10-8atm cc/s air were detected, which is better than the MIL-STD-883G of 5x10-8 atm cc/s air for a package volume of 7.8x10-3 CC. A microprocessor and temperature/humidity sensor was then integrated with the CCR to assemble a passive optical digital data communicator. A flexible circuit design and a folded packaging scheme were utilized to minimize the overall form factor. Flat, flexible polymer batteries were incorporated to reduce the thickness of the package to a few millimeters. The fully packaged sensor system was about 30mmx30mmx6mm. Recorder sensor data was transmitted to a remote location using the CCR, and those results are presented.

  14. What about temperature? Measuring permeability at magmatic conditions.

    NASA Astrophysics Data System (ADS)

    Kushnir, Alexandra R. L.; Martel, Caroline; Champallier, Rémi; Reuschlé, Thierry

    2015-04-01

    The explosive potential of volcanoes is intimately linked to permeability, which is governed by the connectivity of the porous structure of the magma and surrounding edifice. As magma ascends, volatiles exsolve from the melt and expand, creating a gas phase within the conduit. In the absence of a permeable structure capable of dissipating these gases, the propulsive force of an explosive eruption arises from the gas expansion and the build up of subsurface overpressures. Thus, characterizing the permeability of volcanic rocks under in-situ conditions (high temperature and pressure) allows us to better understand the outgassing potential and explosivity of volcanic systems. Current studies of the permeabilities of volcanic rocks generally measure permeability at room temperature using gas permeameters or model permeability using analytic imaging. Our goal is to perform and assess permeability measurements made at high temperature and high pressure in the interest of approaching the permeability of the samples at magmatic conditions. We measure the permeability of andesitic samples expelled during the 2010 Mt. Merapi eruption. We employ and compare two protocols for measuring permeability at high temperature and under high pressure using argon gas in an internally heated Paterson apparatus with an isolated pore fluid system. We first use the pulse decay method to measure the permeability of our samples, then compare these values to permeability measurements performed under steady state flow. We consider the steady state flow method the more rigorous of the two protocols, as we are more capable of accounting for the temperature gradient within the entire pore fluid system. At temperatures in excess of 700°C and pressures of 100 MPa, permeability values plummet by several orders of magnitude. These values are significantly lower than those commonly reported for room temperature permeameter measurements. The reduction in permeability at high temperature is a combination of pressure and possible viscous healing. Importantly, at temperatures above the glass transition temperature (the temperature above which the glass within the sample begins to behave viscously) the permeable structure of the sample becomes increasingly transient. This changeable structure, as well as the technical nuances of high pressure-temperature measurements makes the measurement and interpretation of permeability at high temperatures challenging. Indeed, a re-evaluation of the use of the term 'permeability' when discussing magmas is necessary.

  15. Temperature-dissipation measurements in a turbulent boundary layer

    Microsoft Academic Search

    L. V. Krishnamoorthy; R. A. Antonia

    1987-01-01

    The three components of the temperature dissipation in a turbulent layer were determined using a suction-type wind tunnel experimental facility and integrated-circuit temperature transducers for the measurements. The mean square value of theta(x), the temperature derivative in the longitudinal direction, was determined mainly by the use of Taylor's hypothesis after the verification of this hypothesis at a few locations in

  16. Remote Water Temperature Measurements Based on Brillouin Scattering with a Frequency Doubled Pulsed Yb:doped Fiber Amplifier

    PubMed Central

    Schorstein, Kai; Popescu, Alexandru; Göbel, Marco; Walther, Thomas

    2008-01-01

    Temperature profiles of the ocean are of interest for weather forecasts, climate studies and oceanography in general. Currently, mostly in situ techniques such as fixed buoys or bathythermographs deliver oceanic temperature profiles. A LIDAR method based on Brillouin scattering is an attractive alternative for remote sensing of such water temperature profiles. It makes it possible to deliver cost-effective on-line data covering an extended region of the ocean. The temperature measurement is based on spontaneous Brillouin scattering in water. In this contribution, we present the first water temperature measurements using a Yb:doped pulsed fiber amplifier. The fiber amplifier is a custom designed device which can be operated in a vibrational environment while emitting narrow bandwidth laser pulses. The device shows promising performance and demonstrates the feasibility of this approach. Furthermore, the current status of the receiver is briefly discussed; it is based on an excited state Faraday anomalous dispersion optical filter.

  17. Calculation of smoke plume mass from passive UV satellite measurements by GOME-2 polarization measurement devices

    NASA Astrophysics Data System (ADS)

    Penning de Vries, M. J. M.; Tuinder, O. N. E.; Wagner, T.; Fromm, M.

    2012-04-01

    The Wallow wildfire of 2011 was one of the most devastating fires ever in Arizona, burning over 2,000 km2 in the states of Arizona and New Mexico. The fire originated in the Bear Wallow Wilderness area in June, 2011, and raged for more than a month. The intense heat of the fire caused the formation of a pyro-convective cloud. The resulting smoke plume, partially located above low-lying clouds, was detected by several satellite instruments, including GOME-2 on June 2. The UV Aerosol Index, indicative of aerosol absorption, reached a maximum of 12 on that day, pointing to an elevated plume with moderately absorbing aerosols. We have performed extensive model calculations assuming different aerosol optical properties to determine the total aerosol optical depth of the plume. The plume altitude, needed to constrain the aerosol optical depth, was obtained from independent satellite measurements. The model results were compared with UV Aerosol Index and UV reflectances measured by the GOME-2 polarization measurement devices, which have a spatial resolution of roughly 10x40 km2. Although neither the exact aerosol optical properties nor optical depth can be obtained with this method, the range in aerosol optical depth values that we calculate, combined with the assumed specific extinction mass factor of 5 m2/kg lead us to a rough estimate of the smoke plume mass that cannot, at present, be assessed in another way.

  18. A Novel Device for Total Acoustic Output Measurement of High Power Transducers

    NASA Astrophysics Data System (ADS)

    Howard, S.; Twomey, R.; Morris, H.; Zanelli, C. I.

    2010-03-01

    The objective of this work was to develop a device for ultrasound power measurement applicable over a broad range of medical transducer types, orientations and powers, and which supports automatic measurements to simplify use and minimize errors. Considering all the recommendations from standards such as IEC 61161, an accurate electromagnetic null-balance has been designed for ultrasound power measurements. The sensing element is placed in the water to eliminate errors due to surface tension and water evaporation, and the motion and detection of force is constrained to one axis, to increase immunity to vibration from the floor, water sloshing and water surface waves. A transparent tank was designed so it could easily be submerged in a larger tank to accommodate large transducers or side-firing geometries, and can also be turned upside-down for upward-firing transducers. A vacuum lid allows degassing the water and target in situ. An external control module was designed to operate the sensing/driving loop and to communicate to a local computer for data logging. The sensing algorithm, which incorporates temperature compensation, compares the feedback force needed to cancel the motion for sources in the "on" and "off" states. These two states can be controlled by the control unit or manually by the user, under guidance by a graphical user interface (the system presents measured power live during collection). Software allows calibration to standard weights, or to independently calibrated acoustic sources. The design accommodates a variety of targets, including cone, rubber, brush targets and an oil-filled target for power measurement via buoyancy changes. Measurement examples are presented, including HIFU sources operating at powers from 1 to 100.

  19. Description of modular devices for the measurement of external dosimetry in radiation protection.

    PubMed

    Genicot, Jean Louis; Boogers, Eric; Van Iersel, Mark

    2015-04-01

    In 2002 the Group of Radiation Dosimetry and Calibration of the Belgian Nuclear Research Centre (SCK•CEN) has developed an experimental device based on the optically stimulated luminescence (OSL) working with Al2O3:C detectors (TLD-500 and Luxel) stimulated with an argon laser. A set of devices made from different modules have been developed to permit external dosimetry measurements with thermoluminescence (TL) and OSL techniques under different conditions. This study describes these measurement devices that can be made with these modules and some of the characteristics of the different systems. These devices present several advantages in terms of measurement possibilities: a small number of modules allow the use of different detection materials (Al2O3:C, BeO, quartz electronic components and tiles) and different measurement methods (TL, CW-OSL and pulsed OSL). Some applications are commented. PMID:25236335

  20. Synchrophasor Measurement Using Substation Intelligent Electronic Devices: Algorithms and Test Methodology 

    E-print Network

    Ren, Jinfeng

    2012-02-14

    depict the transient behavior of a synchrophasor unit under the step input. A reference phasor estimator is developed and implemented. Various types of Phasor Measurement Units (PMUs) and PMU-enabled IEDs (Intelligent Electronic Devices) and time...

  1. 5. BURLINGTON DITCH/DENVER WATER DEPARTMENT MEASURING DEVICE Located a short ...

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

    5. BURLINGTON DITCH/DENVER WATER DEPARTMENT MEASURING DEVICE Located a short distance upstream from the Sand Creek siphon - Burlington Ditch, South Platte River Drainage Area, Water District No. 2, Division No. 1, Brighton, Adams County, CO

  2. Stand Alone Pressure Measurement Device (SAPMD) for the space shuttle Orbiter, part 2

    NASA Technical Reports Server (NTRS)

    Tomlinson, Bill

    1989-01-01

    The Stand Alone Pressure Measurement Device (SAPMD) specifications are examined. The HP.SAPMD GSE software is listed; the HP/SGA readme program is presented; and the SPMD acceptance test procedure is described.

  3. A New Device for Mechanical Testing of Blood Vessels at Cryogenic Temperatures.

    PubMed

    Jimenez Rios, Jorge L; Rabin, Yoed

    2007-01-01

    As part of an ongoing program to study the thermo-mechanical effects associated with cryopreservation via vitrification (vitreous in Latin means glassy), the current study focuses on the development of a new device for mechanical testing of blood vessels at cryogenic temperatures. This device is demonstrated on a bovine carotid artery model, permeated with the cryoprotectant cocktail VS55 and a reference solution of 7.05M DMSO, below glass transition. Results are also presented for crystallized specimens, in the absence of cryoprotectants. Results indicate that the elastic modulus of a specimen with no cryoprotectant, at about -140°C (8.6°C and 15.5°C below the glass transition temperature of 7.05M DMSO and VS55, respectively), is 1038.8 ± 25.2 MPa, which is 8% and 3% higher than that of a vitrified specimen permeated with 7.05M DMSO and VS55, respectively. The elastic modulus of a crystallized material at -50°C is lower by ~20% lower from that at -140°C. PMID:18958183

  4. Measurement of electron density and temperature in plasmas

    NASA Technical Reports Server (NTRS)

    Billman, K. W.; Rowley, P. D.; Presley, L. L.; Stallcop, J.

    1972-01-01

    Application of two laser wavelengths passing through plasma measures electron density and temperature. Function depends on determining absorption of light at two wavelengths. Nature of reaction is explained and schematic diagram of equipment is included.

  5. Study of Windows Effects for Shock Wave Temperature Measurements

    SciTech Connect

    W. D. Turley, G. Stevens, L. Veeser, D. Holtkamp, A. Seifter

    2011-05-25

    Temperature measurements of shocked plutonium are needed for improved understanding of its equation of state (EOS) and will enable better understanding and reliability of the U.S. nuclear weapon stockpile.

  6. Active radiometer for self-calibrated furnace temperature measurements

    DOEpatents

    Woskov, P.P.; Cohn, D.R.; Titus, C.H.; Wittle, J.K.; Surma, J.E.

    1996-11-12

    A radiometer is described 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. 5 figs.

  7. POST-SHOCK TEMPERATURE MEASUREMENTS OF ALUMINUM A. Seifter1

    E-print Network

    Stewart, Sarah T.

    POST-SHOCK TEMPERATURE MEASUREMENTS OF ALUMINUM A. Seifter1 , S. T. Stewart2 , M. R. Furlanetto1, Harvard University, 20 Oxford Street, Cambridge MA 02138 Abstract. Post-shock temperature is an important quantity in shock physics experiments for constraining the dynamic equations of state of materials. A high

  8. MEASUREMENT OF THERMAL PROPERTIES OF GYPSUM BOARD AT ELEVATED TEMPERATURES

    Microsoft Academic Search

    SAMUEL L. MANZELLO; SUEL-HYUN PARK; TENSEI MIZUKAMI

    The thermal conductivity, specific heat, mass loss, and linear contraction for gypsum board types widely used in the USA and Japan were measured both at room temperature and elevated temperatures. The gypsum board types tested include Type X and Type C from the USA and Type R and Type F from Japan. Results indicate that the difference in thermal properties

  9. Effective temperatures from the fluctuation-dissipation measurements in soft

    E-print Network

    MacKintosh, F.C.

    of the fluctuation-dissipation theorem (FDT) and the applicability of the concept of effective temperature is to extend the fluctuation dissipation theorem (FDT) to non-equilibrium situations [1]. The FDT relatesOFFPRINT Effective temperatures from the fluctuation-dissipation measurements in soft glassy

  10. A new CR39 nuclear track passive thoron measuring device

    Microsoft Academic Search

    M. Calamosca; S. Penzo

    2009-01-01

    220Rn monitoring in dwellings and in workplaces is seldom performed, both because usually the associated risk is considered negligible and for the difficulties of properly measuring it. As a consequence the state of art of thoron measurements by using solid-state nuclear track detectors shows a significant lag compared with radon. However the demand of determining the thoron contribution to natural

  11. Fast amplitude and delay measurement for characterization of optical devices 

    E-print Network

    Thompson, Michael Thomas

    2006-10-30

    of the measured magnitude response of an Acetylene gas cell and comparing it to the integral of the measured group delay. The average deviation between the two methods is 0.1 radians. An Acetylene gas cell, fiber Bragg grating, and chirped Bragg grating are tested...

  12. 27 CFR 25.42 - Testing of measuring devices.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...gauge glass is used to measure beer, the brewer shall periodically test the measuring...adjust or repair it, if necessary. The brewer shall keep records of tests available...excess of the allowable variation, the brewer shall immediately adjust or repair...

  13. 27 CFR 25.42 - Testing of measuring devices.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...gauge glass is used to measure beer, the brewer shall periodically test the measuring...adjust or repair it, if necessary. The brewer shall keep records of tests available...excess of the allowable variation, the brewer shall immediately adjust or repair...

  14. 27 CFR 25.42 - Testing of measuring devices.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...gauge glass is used to measure beer, the brewer shall periodically test the measuring...adjust or repair it, if necessary. The brewer shall keep records of tests available...excess of the allowable variation, the brewer shall immediately adjust or repair...

  15. Single Cell Magnetic Measurements with a Superconducting Quantum Interference Device

    NASA Astrophysics Data System (ADS)

    Palmstrom, Johanna C.; Arps, Jennifer; Dwyer, Bo; Kalisky, Beena; Kirtley, John R.; Moler, Kathryn A.; Qian, Lisa C.; Rosenberg, Aaron J.; Rutt, Brian; Tee, Sui Seng; Theis, Eric; Urbach, Elana; Wang, Yihua

    2014-03-01

    Magnetic nanoparticles play an important role in numerous biomedical applications such as magnetic resonance imaging and targeted drug delivery. There is a need for tools to characterize individual magnetic nanoparticles and the magnetic properties of individual cells. We use a scanning superconducting quantum interference device (SQUID) to observe the magnetic fields from single mammalian cells loaded with superparamagnetic iron oxide nanoparticles. We show that the SQUID is a useful tool for imaging biological magnetism and is capable of resolving cell to cell variations in magnetic dipole moments. We hope to correlate these magnetic images with real space imaging techniques such as optical and scanning electron microscopy. The visualization of single cell magnetism can be used to optimize biological magnetic imaging techniques, such as MRI, by quantifying the strength of magnetic dipole moments of in vitro magnetic labeling. This work is supported by a National Science Foundation Graduate Research Fellowship and a Gabilan Stanford Graduate Fellowship.

  16. Applications of thin-film thermocouples for surface temperature measurement

    NASA Astrophysics Data System (ADS)

    Martin, Lisa C.; Holanda, Raymond

    1994-10-01

    Thin film thermocouples provide a minimally intrusive means of measuring surface temperature in hostile, high temperature environments. Unlike wire thermocouples, thin films do not necessitate any machining of the surface, thereby leaving intact its structural integrity. Thin films are many orders of magnitude thinner than wire, resulting in less disruption to the gas flow and thermal patterns that exist in the operating environment. Thin film thermocouples have been developed for surface temperature measurement on a variety of engine materials. The sensors are fabricated in the NASA Lewis Research Center's Thin Film Sensor Lab, which is a Class 1000 Clean Room. The thermocouples are platinum-13% rhodium vs platinum and are fabricated by the sputtering process. Thin film-to-leadwire connections are made using the parallel-gap welding process. Thermocouples have been developed for use on superalloys, ceramics and ceramic composites, and intermetallics. Some applications of thin film thermocouples are: temperature measurement of Space Shuttle Main Engine turbine blade materials, temperature measurement in gas turbine engine testing of advanced materials, and temperature and heat flux measurements in a diesel engine. Fabrication of thin film thermocouples is described. Sensor durability, drift rate, and maximum temperature capabilities are addressed.

  17. Titan Surface Temperatures as Measured by Cassini CIRS

    NASA Technical Reports Server (NTRS)

    Jennings, Donald E.; Flasar, F.M.; Kunde, V.G.; Nixon, C.A.; Romani, P.N.; Samuelson, R.E.; Coustenis, A.; Courtin, R.

    2009-01-01

    Thermal radiation from the surface of Titan reaches space through a spectral window of low opacity at 19-microns wavelength. This radiance gives a measure of the brightness temperature of the surface. Composite Infrared Spectrometer' (CIRS) observations from Cassini during its first four years at Saturn have permitted latitude mapping of zonally averaged surface temperatures. The measurements are corrected for atmospheric opacity using the dependence of radiance on emission angle. With the more complete latitude coverage and much larger dataset of CIRS we have improved upon the original results from Voyager IRIS. CIRS measures the equatorial surface brightness temperature to be 93.7+/-0.6 K, the same as the temperature measured at the Huygens landing site. The surface brightness temperature decreases by 2 K toward the south pole and by 3 K toward the north pole. The drop in surface temperature between equator and north pole implies a 50% decrease in methane saturation vapor pressure and relative humidity; this may help explain the large northern lakes. The H2 mole fraction is derived as a by-product of our analysis and agrees with previous results. Evidence of seasonal variation in surface and atmospheric temperatures is emerging from CIRS measurements over the Cassini mission.

  18. Effect of a novel temperature-controlled laminar airflow device on personal breathing zone aeroallergen exposure.

    PubMed

    Gore, R B; Boyle, R J; Gore, C; Custovic, A; Hanna, H; Svensson, P; Warner, J O

    2015-02-01

    Temperature-controlled laminar airflow improves symptoms in atopic asthmatics, but its effects on personal allergen exposure are unknown. We aimed to evaluate its effects on personal cat allergen and particulate exposures in a simulated bedroom environment. Five healthy volunteers lay under an active and an inactive temperature-controlled laminar airflow device for 175 min, in a simulated bedroom containing bedding from a cat owner. Total airborne particles (?0.5 - ?10 ?m diameter) were quantified with a laser particle counter. Airborne allergen was sampled with Institute of Occupational Medicine filters. Inhaled exposure was sampled with nasal air samplers. Allergen-containing particles were quantified by immunoassay. Treatment reduced total airborne particles (>0.5 ?m diameter) by >99% (P < 0.001) and reduced airborne allergen concentration within the breathing zone (ratio of median counts = 30, P = 0.043). Treatment reduced inhaled allergen (ratio of median counts = 7, P = 0.043). Treatment was not associated with a change in airborne allergen concentration outside of the breathing zone (P = 0.160). Temperature-controlled laminar airflow treatment of individuals in an allergen-rich experimental environment results in significant reductions in breathing zone allergenic and non-allergenic particle exposure, and in inhaled cat allergen exposure. These findings may explain the clinical benefits of temperature-controlled laminar airflow. PMID:24750266

  19. Turbine engine hot-part temperature measurement techniques

    NASA Astrophysics Data System (ADS)

    Jackson, A. G.; Prufert, M. B.

    1992-07-01

    The paper identifies altitude test facility techniques for nonintrusive acquisition of hot-part temperatures using IR radiance measurements. The techniques discussed are applicable for turbojet and low-bypass turbofan engines. Constraints limiting IR measurements in the altitude ground test facility are discussed. Methods for evaluating altitude ground test data are outlined including review of predictive capabilities which enable the determination of the influence of turbine engine hot-part temperatures on IR emissions.

  20. Passive Microwave Measurements of Temperature And Salinity in Coastal Zones

    Microsoft Academic Search

    Hans-Juergen C. Blume; Bruce M. Kendall

    1982-01-01

    A technique to remotely measure sea-surface temperature and salinity was demonstrated with a dual-frequency microwave radiometer system developed at the NASA Langley Research Center. Acuracies in temperature of 1°C and 1 part per thousand in salinity were obtained using state-of-the-art radiometers. Several aircraft programs for the measurement of coastal area waters demonstrating the application of the microwave radiometer system are