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Sample records for cold leg thermocouple

  1. Thermocouple shield

    DOEpatents

    Ripley, Edward B.

    2009-11-24

    A thermocouple shield for use in radio frequency fields. In some embodiments the shield includes an electrically conductive tube that houses a standard thermocouple having a thermocouple junction. The electrically conductive tube protects the thermocouple from damage by an RF (including microwave) field and mitigates erroneous temperature readings due to the microwave or RF field. The thermocouple may be surrounded by a ceramic sheath to further protect the thermocouple. The ceramic sheath is generally formed from a material that is transparent to the wavelength of the microwave or RF energy. The microwave transparency property precludes heating of the ceramic sheath due to microwave coupling, which could affect the accuracy of temperature measurements. The ceramic sheath material is typically an electrically insulating material. The electrically insulative properties of the ceramic sheath help avert electrical arcing, which could damage the thermocouple junction. The electrically conductive tube is generally disposed around the thermocouple junction and disposed around at least a portion of the ceramic sheath. The concepts of the thermocouple shield may be incorporated into an integrated shielded thermocouple assembly.

  2. High temperature, oxidation resistant noble metal-Al alloy thermocouple

    NASA Technical Reports Server (NTRS)

    Smialek, James L. (Inventor); Gedwill, Michael G. (Inventor)

    1994-01-01

    A thermocouple is disclosed. The thermocouple is comprised of an electropositive leg formed of a noble metal-Al alloy and an electronegative leg electrically joined to form a thermocouple junction. The thermocouple provides for accurate and reproducible measurement of high temperatures (600 - 1300 C) in inert, oxidizing or reducing environments, gases, or vacuum. Furthermore, the thermocouple circumvents the need for expensive, strategic precious metals such as rhodium as a constituent component. Selective oxidation of rhodium is also thereby precluded.

  3. High-Temperature, Oxidation-Resistant Thermocouples

    NASA Technical Reports Server (NTRS)

    Smialek, James L.; Gedwill, Michael A.

    1994-01-01

    Aluminum substituted for rhodium, which is scarce and expensive. Electromotive force increases with aluminum content in Pt/Al leg of Pt(Pt/Al) thermocouple. Wires baked longer in aluminizing bed produce larger voltages. Thermocouples containing platinum/aluminum legs used instead of thermocouples of type R in furnaces, heat engines, and chemical reactors. Expecially suited to high-velocity oxidizing environments. Constructed as thin-film sensors on turbine blades and vanes, where pre-oxidation provides insulating film needed between thermocouple legs. Because aluminum content slowly depleted by oxidation, long-term use recommended only where maximum temperature is 1,200 degrees C or less.

  4. Thermocouple installation

    NASA Technical Reports Server (NTRS)

    Powell, W. B.; Potter, L. R.; Macdavid, K. S. (Inventor)

    1976-01-01

    A thermocouple assembly which includes a plug having a pair of small diameter holes near one end thereof which are spaced a small distance apart to leave a thin quantity of plug material between the holes is presented. There are a pair of thermocouple wires extending through the different holes and with the outer ends of the wires joined to the thin quantity of plug material which lies between the holes to form a thermocouple junction.

  5. Water-hammer in the cold leg during an SBLOCA due to cold ECCS injection

    SciTech Connect

    Ortiz, M.G.; Ghan, L.S.

    1991-12-01

    Water-hammer might occur in the cold leg of pressurized water reactors (PWR) during small break loss-of-coolant accidents (SBLOCA`s), when cold emergency core cooling system (ECCS) water is injected into a pipe that may be partially filled with saturated steam. The water may mix with the steam and cause it to condense abruptly. Depending on the flow regime present, slugs of liquid may then be accelerated towards each other or against the piping structure. The possibility of this phenomenon is of concern to us because it may become a dominant phenomenon and change the character of the transient. In performing the code scaling, applicability, and uncertainty study (CSAU) on a SBLOCA scenario, we had to examine the possibility that the transient being analyzed could experience water-hammer and thus depart from the scope of the study. Two criteria for water-hammer initiation were investigated and tested using a RELAP5/MOD3 simulation of the transient. Our results indicated a very low likelihood of occurrence of the phenomenon. 8 refs., 6 figs.

  6. Water-hammer in the cold leg during an SBLOCA due to cold ECCS injection

    SciTech Connect

    Ortiz, M.G.; Ghan, L.S.

    1991-01-01

    Water-hammer might occur in the cold leg of pressurized water reactors (PWR) during small break loss-of-coolant accidents (SBLOCA's), when cold emergency core cooling system (ECCS) water is injected into a pipe that may be partially filled with saturated steam. The water may mix with the steam and cause it to condense abruptly. Depending on the flow regime present, slugs of liquid may then be accelerated towards each other or against the piping structure. The possibility of this phenomenon is of concern to us because it may become a dominant phenomenon and change the character of the transient. In performing the code scaling, applicability, and uncertainty study (CSAU) on a SBLOCA scenario, we had to examine the possibility that the transient being analyzed could experience water-hammer and thus depart from the scope of the study. Two criteria for water-hammer initiation were investigated and tested using a RELAP5/MOD3 simulation of the transient. Our results indicated a very low likelihood of occurrence of the phenomenon. 8 refs., 6 figs.

  7. Thermocouple tape

    NASA Technical Reports Server (NTRS)

    Mazaris, G. A., Jr.; Thomas, R. D.

    1972-01-01

    Preformed, low cost, thin film thermocouples on adhesive tapes were fabricated. Metal strips of two dissimilar metals were laid on opposite edges of plastic substrate so that they overlap in center portion, forming thermocouple junction. Useful temperature range for polyimide films was 4 to 673 K.

  8. Thermocouple assembly

    DOEpatents

    Thermos, Anthony Constantine; Rahal, Fadi Elias

    2002-01-01

    A thermocouple assembly includes a thermocouple; a plurality of lead wires extending from the thermocouple; an insulating jacket extending along and enclosing the plurality of leads; and at least one internally sealed area within the insulating jacket to prevent fluid leakage along and within the insulating jacket. The invention also provides a method of preventing leakage of a fluid along and through an insulating jacket of a thermocouple including the steps of a) attaching a plurality of lead wires to a thermocouple; b) adding a heat sensitive pseudo-wire to extend along the plurality of lead wires; c) enclosing the lead wires and pseudo-wire inside an insulating jacket; d) locally heating axially spaced portions of the insulating jacket to a temperature which melts the pseudo-wire and fuses it with an interior surface of the jacket.

  9. Locating hot and cold-legs in a nuclear powered steam generation system

    DOEpatents

    Ekeroth, Douglas E.; Corletti, Michael M.

    1993-01-01

    A nuclear reactor steam generator includes a reactor vessel for heating water and a steam generator with a pump casing at the lowest point on the steam generator. A cold-leg pipe extends horizontally between the steam generator and the reactor vessel to return water from the steam generator to the reactor vessel. The bottom of the cold-leg pipe is at a first height above the bottom of the reactor vessel. A hot-leg pipe with one end connected to the steam generator and a second end connected to the reactor vessel has a first pipe region extending downwardly from the steam generator to a location between the steam generator and the reactor vessel at which a bottom of the hot-leg pipe is at a second height above the bottom of the reactor vessel. A second region extends from that location in a horizontal direction at the second height to the point at which the hot-leg pipe connects to the reactor vessel. A pump is attached to the casing at a location below the first and second heights and returns water from the steam generator to the reactor vessel over the cold-leg. The first height is greater than the second height and the bottom of the steam generator is at a height above the bottom of the reactor vessel that is greater than the first and second heights. A residual heat recovery pump is below the hot-leg and has an inlet line from the hot-leg that slopes down continuously to the pump inlet.

  10. Locating hot and cold-legs in a nuclear powered steam generation system

    DOEpatents

    Ekeroth, D.E.; Corletti, M.M.

    1993-11-16

    A nuclear reactor steam generator includes a reactor vessel for heating water and a steam generator with a pump casing at the lowest point on the steam generator. A cold-leg pipe extends horizontally between the steam generator and the reactor vessel to return water from the steam generator to the reactor vessel. The bottom of the cold-leg pipe is at a first height above the bottom of the reactor vessel. A hot-leg pipe with one end connected to the steam generator and a second end connected to the reactor vessel has a first pipe region extending downwardly from the steam generator to a location between the steam generator and the reactor vessel at which a bottom of the hot-leg pipe is at a second height above the bottom of the reactor vessel. A second region extends from that location in a horizontal direction at the second height to the point at which the hot-leg pipe connects to the reactor vessel. A pump is attached to the casing at a location below the first and second heights and returns water from the steam generator to the reactor vessel over the cold-leg. The first height is greater than the second height and the bottom of the steam generator is at a height above the bottom of the reactor vessel that is greater than the first and second heights. A residual heat recovery pump is below the hot-leg and has an inlet line from the hot-leg that slopes down continuously to the pump inlet. 2 figures.

  11. High temperature thermocouple operates in reduction atmosphere

    NASA Technical Reports Server (NTRS)

    Hoff, R. G.

    1966-01-01

    Thermocouple continuously measures a flowing gas up to 4500 degrees F in a hazardous environment. The thermocouple combines rhenium and tungsten in the probe, housing, and swaged extension lead. The wires extend continuously from the cold junction to the probe tip to eliminate errors from secondary thermocouple effects.

  12. Thermocouple tape

    NASA Technical Reports Server (NTRS)

    Thomas, R. D. (Inventor)

    1973-01-01

    A thermocouple which may be rolled as a tape until needed and a method of making it are described. Thermoelectrically different metals are applied to a strip of electrically nonconductive material in longitudinally overlapping relationship. Apertures may be provided along the tape in overlapping region at predetermined intervals. An adhesive material is applied to the side of the tape opposite the thermoelectric metals either before or after the thermoelectric metals are deposited. The tape may be cut or torn to form a thermocouple device which is ready for application to a body whose temperature is to be monitored or measured.

  13. Instrumentation System Diagnoses a Thermocouple

    NASA Technical Reports Server (NTRS)

    Perotti, Jose; Santiago, Josephine; Mata, Carlos; Vokrot, Peter; Zavala, Carlos; Burns, Bradley

    2008-01-01

    An improved self-validating thermocouple (SVT) instrumentation system not only acquires readings from a thermocouple but is also capable of detecting deterioration and a variety of discrete faults in the thermocouple and its lead wires. Prime examples of detectable discrete faults and deterioration include open- and short-circuit conditions and debonding of the thermocouple junction from the object, the temperature of which one seeks to measure. Debonding is the most common cause of errors in thermocouple measurements, but most prior SVT instrumentation systems have not been capable of detecting debonding. The improved SVT instrumentation system includes power circuitry, a cold-junction compensator, signal-conditioning circuitry, pulse-width-modulation (PWM) thermocouple-excitation circuitry, an analog-to-digital converter (ADC), a digital data processor, and a universal serial bus (USB) interface. The system can operate in any of the following three modes: temperature measurement, thermocouple validation, and bonding/debonding detection. The software running in the processor includes components that implement statistical algorithms to evaluate the state of the thermocouple and the instrumentation system. When the power is first turned on, the user can elect to start a diagnosis/ monitoring sequence, in which the PWM is used to estimate the characteristic times corresponding to the correct configuration. The user also has the option of using previous diagnostic values, which are stored in an electrically erasable, programmable read-only memory so that they are available every time the power is turned on.

  14. SPACE code simulation of cold leg small break LOCA in the ATLAS integral test

    SciTech Connect

    Kim, B. J.; Kim, H. T.; Kim, J.; Kim, K. D.

    2012-07-01

    SPACE code is a system analysis code for pressurized water reactors. This code uses a two-fluid and three-field model. For a few years, intensive validations have been performed to secure the prediction accuracy of models and correlations for two-phase flow and heat transfer. Recently, the code version 1.0 was released. This study is to see how well SPACE code predicts thermal hydraulic phenomena of an integral effect test. The target experiment is a cold leg small break LOCA in the ATLAS facility, which has the same two-loop features as APR1400. Predicted parameters were compared with experimental observations. (authors)

  15. Human thermal responses during leg-only exercise in cold water.

    PubMed Central

    Golden, F S; Tipton, M J

    1987-01-01

    1. Exercise during immersion in cold water has been reported by several authors to accelerate the rate of fall of core temperature when compared with rates seen during static immersion. The nature of the exercise performed, however, has always been whole-body in nature. 2. In the present investigation fifteen subjects performed leg exercise throughout a 40 min head-out immersion in water at 15 degrees C. The responses obtained were compared with those seen when the subjects performed an identical static immersion. 3. Aural and rectal temperatures were found to fall by greater amounts during static immersion. 4. It is concluded that 'the type of exercise performed' should be included in the list of factors which affect core temperature during cold water immersion. PMID:3443951

  16. Oxidation Protection for Thermocouples

    NASA Technical Reports Server (NTRS)

    Richter, R.

    1984-01-01

    Thin platinum film on thermocouple sheath protects non-noble-metal thermocouples from deterioration in oxygen-rich atmosphere. Coating works on nickel-alloy sheathed thermocouples otherwise destroyed by corrosion in pure oxygen at 1,000 degrees C.

  17. Theory and performance of plated thermocouples.

    NASA Technical Reports Server (NTRS)

    Pesko, R. N.; Ash, R. L.; Cupschalk, S. G.; Germain, E. F.

    1972-01-01

    A theory has been developed to describe the performance of thermocouples which have been formed by electroplating portions of one thermoelectric material with another. The electroplated leg of the thermocouple was modeled as a collection of infinitesimally small homogeneous thermocouples connected in series. Experiments were performed using several combinations of Constantan wire sizes and copper plating thicknesses. A transient method was used to develop the thermoelectric calibrations, and the theory was found to be in quite good agreement with the experiments. In addition, data gathered in a Soviet experiment were also found to be in close agreement with the theory.

  18. Self-Validating Thermocouple

    NASA Technical Reports Server (NTRS)

    Perotti, Jose M. (Inventor); Mata, Carlos T. (Inventor); Santiago, Josephine B. (Inventor); Vokrot, Peter (Inventor); Zavala, Carlos E. (Inventor); Burns, Bradley M. (Inventor)

    2010-01-01

    Self-Validating Thermocouple (SVT) Systems capable of detecting sensor probe open circuits, short circuits, and unnoticeable faults such as a probe debonding and probe degradation are useful in the measurement of temperatures. SVT Systems provide such capabilities by incorporating a heating or excitation element into the measuring junction of the thermocouple. By heating the measuring junction and observing the decay time for the detected DC voltage signal, it is possible to indicate whether the thermocouple is bonded or debonded. A change in the thermal transfer function of the thermocouple system causes a change in the rise and decay times of the thermocouple output. Incorporation of the excitation element does not interfere with normal thermocouple operation, thus further allowing traditional validation procedures as well.

  19. COMMIX-1A analysis of fluid and thermal mixing in a model cold leg and downcomer of a PWR

    SciTech Connect

    Chen, B.C.J.; Cha, B.K.; Miao, C.C.; Sha, W.T.; Kim, J.H.; Sun, B.K.H.

    1983-01-01

    The issue of thermal shock of a PWR pressure vessel has been under considerable attention recently. A number of experimental as well as analytical studies have been performed to investigate the effect of the thermal transient on the pressure vessel due to the high pressure injection (HPI) of the cold fluid into the cold leg. This process has been called Pressurized Thermal Shock (PTS). This paper is an analytical study of PTS by using COMMIX-1A. Experimental investigations were performed at CREARE and SAI. In the CREARE experiment, a 1/5 scale model was set up to simulate a cold leg and downcomer of a PWR. Tests with several different ratios of hot loop flow versus cold HPI flow were performed to study the effect of the flow ratio on the fluid and thermal mixing process in the system, especially in the downcomer region. Analytical investigations also proceeded in parallel with the experiments. Quite a few analytical investigations were performed with the COMMIX-1A code. However, in this version of COMMIX, the effect of the numerical diffusion was not addressed.

  20. Thermocouple design for measuring temperatures of small insects.

    PubMed

    Hanson, A A; Venette, R C

    2013-01-01

    Contact thermocouples often are used to measure surface body temperature changes of insects during cold exposure. However, small temperature changes of minute insects can be difficult to detect, particularly during the measurement of supercooling points. We developed two thermocouple designs, which use 0.51 mm diameter or 0.127 mm diameter copper-constantan wires, to improve our ability to resolve insect exotherms. We tested the designs with adults from three parasitoid species: Tetrastichus planipennisi, Spathius agrili, and S. floridanus. These species are <3 mm long and <0.1 mg. Mean exotherms were greater for fine-gauge thermocouples than thick-gauge thermocouples for the smallest species tested, T. planipennisi. This difference was not apparent for larger species S. agrili and S. floridanus. Thermocouple design did not affect the mean supercooling point for any of the species. The cradle thermocouple design developed with the fine gauge wire was reusable and allowed for easy insect recovery after cold exposure.

  1. HIGH TEMPERATURE THERMOCOUPLE

    DOEpatents

    Eshayu, A.M.

    1963-02-12

    This invention contemplates a high temperature thermocouple for use in an inert or a reducing atmosphere. The thermocouple limbs are made of rhenium and graphite and these limbs are connected at their hot ends in compressed removable contact. The rhenium and graphite are of high purity and are substantially stable and free from diffusion into each other even without shielding. Also, the graphite may be thick enough to support the thermocouple in a gas stream. (AEC)

  2. Thin film ceramic thermocouples

    NASA Technical Reports Server (NTRS)

    Gregory, Otto (Inventor); Fralick, Gustave (Inventor); Wrbanek, John (Inventor); You, Tao (Inventor)

    2011-01-01

    A thin film ceramic thermocouple (10) having two ceramic thermocouple (12, 14) that are in contact with each other in at least on point to form a junction, and wherein each element was prepared in a different oxygen/nitrogen/argon plasma. Since each element is prepared under different plasma conditions, they have different electrical conductivity and different charge carrier concentration. The thin film thermocouple (10) can be transparent. A versatile ceramic sensor system having an RTD heat flux sensor can be combined with a thermocouple and a strain sensor to yield a multifunctional ceramic sensor array. The transparent ceramic temperature sensor that could ultimately be used for calibration of optical sensors.

  3. Modern Thermocouple Experiment.

    ERIC Educational Resources Information Center

    Chang, K. N.; And Others

    1978-01-01

    Describes a thermocouple circuit used to measure Joule heating as well as Peltier heating and cooling for a copper-Constantan metallic junction. Shows how the Seebeck effect from a thermocouple can monitor the temperature condition of a junction with regard to input power and Peltier effect. (Author/GA)

  4. Spring loaded thermocouple module

    DOEpatents

    McKelvey, T.E.; Guarnieri, J.J.

    1984-03-13

    A thermocouple arrangement is provided for mounting in a blind hole of a specimen. The thermocouple arrangement includes a cup-like holder member, which receives an elongated thermal insulator, one end of which is seated at an end wall of the holder. A pair of thermocouple wires, threaded through passageways in the insulator, extend beyond the insulator member, terminating in free ends which are joined together in a spherical weld bead. A spring, held captive within the holder, applies a bias force to the weld bead, through the insulator member. The outside surface of the holder is threaded for engagement with the blind hole of the specimen. When the thermocouple is installed in the specimen, the spherical contact surface of the weld bead is held in contact with the end wall of the blind hole, with a predetermined bias force.

  5. Spring loaded thermocouple module

    DOEpatents

    McKelvey, Thomas E.; Guarnieri, Joseph J.

    1985-01-01

    A thermocouple arrangement is provided for mounting in a blind hole of a specimen. The thermocouple arrangement includes a cup-like holder member, which receives an elongated thermal insulator, one end of which is seated at an end wall of the holder. A pair of thermocouple wires, threaded through passageways in the insulator, extend beyond the insulator member, terminating in free ends which are joined together in a spherical weld bead. A spring, held captive within the holder, applies a bias force to the weld bead, through the insulator member. The outside surface of the holder is threaded for engagement with the blind hole of the specimen. When the thermocouple is installed in the specimen, the spherical contact surface of the weld bead is held in contact with the end wall of the blind hole, with a predetermined bias force.

  6. ITS-90 Thermocouple Database

    National Institute of Standards and Technology Data Gateway

    SRD 60 NIST ITS-90 Thermocouple Database (Web, free access)   Web version of Standard Reference Database 60 and NIST Monograph 175. The database gives temperature -- electromotive force (emf) reference functions and tables for the letter-designated thermocouple types B, E, J, K, N, R, S and T. These reference functions have been adopted as standards by the American Society for Testing and Materials (ASTM) and the International Electrotechnical Commission (IEC).

  7. Thread-Mounted Thermocouple

    NASA Technical Reports Server (NTRS)

    Ward, Stanley W.

    1988-01-01

    Thread-mounted thermocouple developed to accurately measure temperature of surrounding material. Comprised of threaded rod or bolt drilled along length, dual-hole ceramic insulator rod, thermocouple wire, optional ceramic filler, and epoxy resin. In contact with and takes average temperature of, surrounding material. Fabricated easily in size and metal to suit particular application. Because of simplicity and ability to measure average temperature, widespread use of design foreseen in varity of applications.

  8. Threaded average temperature thermocouple

    NASA Technical Reports Server (NTRS)

    Ward, Stanley W. (Inventor)

    1990-01-01

    A threaded average temperature thermocouple 11 is provided to measure the average temperature of a test situs of a test material 30. A ceramic insulator rod 15 with two parallel holes 17 and 18 through the length thereof is securely fitted in a cylinder 16, which is bored along the longitudinal axis of symmetry of threaded bolt 12. Threaded bolt 12 is composed of material having thermal properties similar to those of test material 30. Leads of a thermocouple wire 20 leading from a remotely situated temperature sensing device 35 are each fed through one of the holes 17 or 18, secured at head end 13 of ceramic insulator rod 15, and exit at tip end 14. Each lead of thermocouple wire 20 is bent into and secured in an opposite radial groove 25 in tip end 14 of threaded bolt 12. Resulting threaded average temperature thermocouple 11 is ready to be inserted into cylindrical receptacle 32. The tip end 14 of the threaded average temperature thermocouple 11 is in intimate contact with receptacle 32. A jam nut 36 secures the threaded average temperature thermocouple 11 to test material 30.

  9. EBR-II in-vessel natural circulation experiments on hot and cold pool stratification

    SciTech Connect

    Ragland, W.A.; Feldman, E.E.

    1990-01-01

    The Experimental Breeder Reactor II is located in a cylindrical pool of liquid sodium which is part of the cold-leg of the primary flow circuit. A vertical string of 32 thermocouples spans the 8 m tank height, at each of two diametrically opposed locations in the primary tank. Local temperatures were measured with these 64 thermocouples during dynamic tests. The instantaneous spacial temperature distribution obtained from a string of thermocouples can be viewed on a personal computer. The animation which results from displaying successive spacial distributions provide a very effective way to quickly obtain physical insights. The design of the two strings of thermocouples, the software used to create the animation, measured data from three different types of tests--two unprotected reactor transients, and one with the reactor at decay power levels and the reactor cover lifted, are discussed. 5 refs., 3 figs.

  10. Thermocouple-Signal-Conditioning Circuit

    NASA Technical Reports Server (NTRS)

    Simon, Richard A.

    1991-01-01

    Thermocouple-signal-conditioning circuit acting in conjunction with thermocouple, exhibits electrical behavior of voltage in series with resistance. Combination part of input bridge circuit of controller. Circuit configured for either of two specific applications by selection of alternative resistances and supply voltages. Includes alarm circuit detecting open circuit in thermocouple and provides off-scale output to signal malfunctions.

  11. Advanced thin film thermocouples

    NASA Technical Reports Server (NTRS)

    Kreider, K. G.; Semancik, S.; Olson, C.

    1984-01-01

    The fabrication, materials characterization, and performance of thin film platinum rhodium thermocouples on gas turbine alloys was investigated. The materials chosen for the study were the turbine blade alloy systems MAR M200+Hf with NiCoCrAlY and FeCrAlY coatings, and vane alloy systems MAR M509 with FeCrAlY. Research was focussed on making improvements in the problem areas of coating substrate stability, adhesion, and insulation reliability and durability. Diffusion profiles between the substrate and coating with and without barrier coatings of Al2O3 are reported. The relationships between fabrication parameters of thermal oxidation and sputtering of the insulator and its characterization and performance are described. The best thin film thermocouples were fabricated with the NiCoCrAlY coatings which were thermally oxidized and sputter coated with Al2O3.

  12. Program Processes Thermocouple Readings

    NASA Technical Reports Server (NTRS)

    Quave, Christine A.; Nail, William, III

    1995-01-01

    Digital Signal Processor for Thermocouples (DART) computer program implements precise and fast method of converting voltage to temperature for large-temperature-range thermocouple applications. Written using LabVIEW software. DART available only as object code for use on Macintosh II FX or higher-series computers running System 7.0 or later and IBM PC-series and compatible computers running Microsoft Windows 3.1. Macintosh version of DART (SSC-00032) requires LabVIEW 2.2.1 or 3.0 for execution. IBM PC version (SSC-00031) requires LabVIEW 3.0 for Windows 3.1. LabVIEW software product of National Instruments and not included with program.

  13. Magnetic effects on thermocouples

    NASA Astrophysics Data System (ADS)

    Beguš, Samo; Bojkovski, Jovan; Drnovšek, Janko; Geršak, Gregor

    2014-03-01

    Thermometers in laboratory environment and industrial applications are often subject to extraneous, usually unwanted and uncontrolled magnetic fields. Magnetic field influence can be minimized, but cannot be fully cancelled out. Even more, in most cases, there is no awareness of the existence of magnetic fields, let alone their effect on measurement instrumentation. In the past, sensitivity to high dc magnetic fields has been investigated in cryogenics and at high temperatures. More recently, the magnetic effect on weak dc magnetic fields was presented. The goal of this paper was to analyse and empirically and experimentally prove the magnetic sensitivity of thermocouples exposed to low magnetic fields: both dc and ac. Precision and uniform alternating and direct magnetic flux densities were generated by means of permanent magnets and power amplifiers with air-cored coils. The magnetic effect on ferromagnetic and non-ferromagnetic thermocouples at liquid-nitrogen-boiling point (-196 °C), ice point (0 °C), in water (17 °C) and at melting point of gallium fixed point cell (29.7646 °C) was investigated. Magnetic-field-dependent temperature errors of up to 700 mK (at 5.3 mT: dc) and up to 1 °C (at 10 mT: ac 50 Hz magnetic fields) were detected. From the results, it can be concluded that, ideally for temperature measurements of the highest accuracy in the above-cryogenic temperature range, magnetic sensitivity should be estimated and taken into account either as the correction of an error and/or as an additional source of measurement uncertainty. Special consideration should be given to thermocouple orientation relative to the magnetic field direction, influence of metal enclosures and magnetization effects on ferromagnetic components of thermocouples.

  14. Assessment of RELAP/MOD3 using BETHSY 6.2TC 6-inch cold leg side break comparative test

    SciTech Connect

    Chung, Young-Jong; Jeong, Jae-Jun; Chang, Won-Pyo; Kim, Dong-Su

    1996-10-01

    This report presents the results of the RELAP5/MOD3 Version 7j assessment on BETHSY 6.2TC. BETHSY 6.2TC test corresponding to a six inch cold leg break LOCA of the Pressurizer Water Reactor(PWR). The primary objective of the test was to provide reference data of two facilities of different scales (BETHSY and LSTF facility). On the other hand, the present calculation aims at analysis of RELAP5/N4OD3 capability on the small break LOCA simulation, The results of calculation have shown that the RELAP5/MOD3 reasonably predicts occurrences as well as trends of the major phenomena such as primary pressure, timing of loop seal clearing, liquid hold up, etc. However, some disagreements also have been found in the predictions of loop seal clearing, collapsed core water level after loop seal clearing, and accumulator injection behaviors. For better understanding of discrepancies in same predictions, several sensitivity calculations have been performed as well. These include the changes of two-phase discharge coefficient at the break junction and some corrections of the interphase drag term. As result, change of a single parameter has not improved the overall predictions and it has been found that the interphase drag model has still large uncertainties.

  15. Liquid trap seals thermocouple leads

    NASA Technical Reports Server (NTRS)

    Ruppe, E. P.

    1966-01-01

    Liquid trap seals thermocouple leads coming out of a brazing retort that operates with a controlled atmosphere so that air cannot enter the retort and hydrogen cannot escape. The trap is fastened to a duct welded to the retort. Thermocouple leads are led out through the duct and trap, with the fluid forming a gastight seal between the atmosphere and the retort.

  16. Annealing Increases Stability Of Iridium Thermocouples

    NASA Technical Reports Server (NTRS)

    Germain, Edward F.; Daryabeigi, Kamran; Alderfer, David W.; Wright, Robert E.; Ahmed, Shaffiq

    1989-01-01

    Metallurgical studies carried out on samples of iridium versus iridium/40-percent rhodium thermocouples in condition received from manufacturer. Metallurgical studies included x-ray, macroscopic, resistance, and metallographic studies. Revealed large amount of internal stress caused by cold-working during manufacturing, and large number of segregations and inhomogeneities. Samples annealed in furnace at temperatures from 1,000 to 2,000 degree C for intervals up to 1 h to study effects of heat treatment. Wire annealed by this procedure found to be ductile.

  17. High-temperature thermocouples and related methods

    DOEpatents

    Rempe, Joy L [Idaho Falls, ID; Knudson, Darrell L [Firth, ID; Condie, Keith G [Idaho Falls, ID; Wilkins, S Curt [Idaho Falls, ID

    2011-01-18

    A high-temperature thermocouple and methods for fabricating a thermocouple capable of long-term operation in high-temperature, hostile environments without significant signal degradation or shortened thermocouple lifetime due to heat induced brittleness.

  18. A study of thermal stratification in the cold legs during the subcooled blowdown phase of a loss of coolant accident in the OSU APEX thermal hydraulic testing facility.

    SciTech Connect

    Wachs, D. M.

    1998-11-04

    Thermal stratification, which has been linked to the occurrence of pressurized thermal shock (PTS), is observed to occur during the early stages of simulated loss of coolant accidents (LOCAS) in the Oregon State University Advanced Plant Experiment (OSU APEX) Thermal Hydraulic Test Facility. The OSU APEX Test Facility is a scaled model of the Westinghouse AP600 nuclear power plant. Analysis of the OSU APEX facility data has allowed the determination of an onset criteria for thermal stratification and has provided support for the postulated mechanisms leading to thermal stratification. CFX 4.1, a computational fluid dynamics code, was used to generate a model of the cold legs and the downcomer that described the phenomena occurring within them. Some mixing phenomena were predicted that lead to non-uniformity between the two cold legs attached to the steam generator on the side of the facility containing the Passive Residual Heat Removal (PRHR) injection system. The stratification was found to be two phase and unlikely to be a factor in PTS.

  19. Blackbody comparator for thermocouple calibration

    SciTech Connect

    Ojanen, M.; Hahtela, O. M.; Heinonen, M.

    2013-09-11

    MIKES is developing a measurement set-up for calibrating thermocouples in the temperature range 960 °C - 1500 °C. The calibration method is based on direct comparison of thermocouples and radiation thermometers. We have designed a graphite blackbody comparator cell, which is operated in a horizontal single-zone tube furnace. The cell includes two blackbody cavities for radiation temperature measurements. The cavities have openings on opposite sides of the cell, allowing simultaneous measurement with two radiation thermometers. The design of the comparator allows three thermocouples to be calibrated simultaneously. The thermocouples to be calibrated are inserted in thermometer wells around one of the measurement cavities. We characterize the blackbody comparator in terms of repeatability, temperature distribution and emissivity. Finally, we validate the uncertainty analysis by comparing calibration results obtained for type B and S thermocouples to the calibration results reported by Technical Research Institute of Sweden (SP), and MIKES. The agreement in the temperature range 1000 °C - 1500 °C is within 0.90 °C, the average deviation being 0.17 °C.

  20. Temperature monitoring device and thermocouple assembly therefor

    SciTech Connect

    Grimm, Noel P.; Bauer, Frank I.; Bengel, Thomas G.; Kothmann, Richard E.; Mavretish, Robert S.; Miller, Phillip E.; Nath, Raymond J.; Salton, Robert B.

    1991-01-01

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

  1. Heat penetration and thermocouple location in home canning.

    PubMed

    Etzel, Mark R; Willmore, Paola; Ingham, Barbara H

    2015-01-01

    We processed applesauce, tomato juice, and cranberries in pint jars in a boiling water canner to test thermal processing theories against home canning of high-acid foods. For each product, thermocouples were placed at various heights in the jar. Values for f h (heating), f cl (cooling), and F 82.2°C (lethality) were determined for each thermocouple location, and did not depend substantially on thermocouple location in accordance with heat transfer theory. There was a cold spot in the jar, but the cold spot during heating became the hot spot during cooling. During heating, the geometric center was the last to heat, and remained coldest the longest, but during coooling, it was also the last to cool, and remained hottest the longest. The net effect was that calculated lethality in home canning was not affected by thermocouple location. Most of the lethality during home canning occurred during air cooling, making cooling of home canned foods of great importance. Calculated lethality was far greater than the required 5-log reduction of spores in tomato juice and vegetative cells in cranberries, suggesting a wide margin of safety for approved home-canning processes for high-acid foods.

  2. Thermal Preconditioning of MIMS Type K Thermocouples to Reduce Drift

    NASA Astrophysics Data System (ADS)

    Webster, E. S.

    2017-01-01

    Type K thermocouples are the most widely used temperature sensors in industry and are often used in the convenient mineral-insulated metal-sheathed (MIMS) format. The MIMS format provides almost total immunity to oxide-related drift in the 800°C-1000°C range. However, crystalline ordering of the atomic structure causes drift in the range 200°C-600°C. Troublesomely, the effects of this ordering are reversible, leading to hysteresis in some applications. Typically, MIMS cable is subjected to a post-manufacturing high-temperature recrystallization anneal to remove cold-work and place the thermocouple in a `known state.' However, variations in the temperatures and times of these exposures can lead to variations in the `as-received state.' This study gives guidelines on the best thermal preconditioning of 3 mm MIMS Type K thermocouples in order to minimize drift and achieve the most reproducible temperature measurements. Experimental results demonstrate the consequences of using Type K MIMS thermocouples in different states, including the as-received state, after a high-temperature recrystallization anneal and after preconditioning anneals at 200°C, 300°, 400°C and and 500°C. It is also shown that meaningful calibration is possible with the use of regular preconditioning anneals.

  3. Thermocouple, multiple junction reference oven

    NASA Technical Reports Server (NTRS)

    Leblanc, L. P. (Inventor)

    1981-01-01

    An improved oven for maintaining the junctions of a plurality of reference thermocouples at a common and constant temperature is described. The oven is characterized by a cylindrical body defining a heat sink with axially extended-cylindrical cavity a singularized heating element which comprises a unitary cylindrical heating element consisting of a resistance heating coil wound about the surface of metallic spool with an axial bore defined and seated in the cavity. Other features of the oven include an annular array of radially extended bores defined in the cylindrical body and a plurality of reference thermocouple junctions seated in the bores in uniformly spaced relation with the heating element, and a temperature sensing device seated in the axial bore for detecting temperature changes as they occur in the spool and circuit to apply a voltage across the coil in response to detected drops in temperatures of the spool.

  4. Correction for Thermal EMFs in Thermocouple Feedthroughs

    NASA Technical Reports Server (NTRS)

    Ziemke, Robert A.

    2006-01-01

    A straightforward measurement technique provides for correction of thermal-electromotive-force (thermal-EMF) errors introduced by temperature gradients along the pins of non-thermocouple-alloy hermetic feedthrough connectors for thermocouple extension wires that must pass through bulkheads. This technique is an alternative to the traditional technique in which the thermal-EMF errors are eliminated by use of custom-made multipin hermetic feedthrough connectors that contain pins made of the same alloys as those of the thermocouple extension wires. One disadvantage of the traditional technique is that it is expensive and time-consuming to fabricate multipin custom thermocouple connectors. In addition, the thermocouple-alloy pins in these connectors tend to corrode easily and/or tend to be less rugged compared to the non-thermocouple-alloy pins of ordinary connectors. As the number of thermocouples (and thus pins) is increased in a given setup, the magnitude of these disadvantages increases accordingly. The present technique is implemented by means of a little additional hardware and software, the cost of which is more than offset by the savings incurred through the use of ordinary instead of thermocouple connectors. The figure schematically depicts a typical measurement setup to which the technique is applied. The additional hardware includes an isothermal block (made of copper) instrumented with a reference thermocouple and a compensation thermocouple. The reference thermocouple is connected to an external data-acquisition system (DAS) through a two-pin thermocouple-alloy hermetic feedthrough connector, but this is the only such connector in the apparatus. The compensation thermocouple is connected to the DAS through two pins of the same ordinary multipin connector that connects the measurement thermocouples to the DAS.

  5. Method for bonding thin film thermocouples to ceramics

    DOEpatents

    Kreider, Kenneth G.

    1993-01-01

    A method is provided for adhering a thin film metal thermocouple to a ceramic substrate used in an environment up to 700 degrees Centigrade, such as at a cylinder of an internal combustion engine. The method includes the steps of: depositing a thin layer of a reactive metal on a clean ceramic substrate; and depositing thin layers of platinum and a platinum-10% rhodium alloy forming the respective legs of the thermocouple on the reactive metal layer. The reactive metal layer serves as a bond coat between the thin noble metal thermocouple layers and the ceramic substrate. The thin layers of noble metal are in the range of 1-4 micrometers thick. Preferably, the ceramic substrate is selected from the group consisting of alumina and partially stabilized zirconia. Preferably, the thin layer of reactive metal is in the range of 0.015-0.030 micrometers (15-30 nanometers) thick. The preferred reactive metal is chromium. Other reactive metals may be titanium or zirconium. The thin layer of reactive metal may be deposited by sputtering in ultra high purity argon in a vacuum of approximately 2 milliTorr (0.3 Pascals).

  6. Apparatus Tests Thermocouples For Seebeck Inhomogeneity

    NASA Technical Reports Server (NTRS)

    Burkett, Cecil G., Jr.; Bauserman, Willard A., Jr.; West, James W.

    1995-01-01

    Automated apparatus reveals sources of error not revealed in calibration. Computer-controlled apparatus detects and measures Seebeck inhomogeneities in sheathed thermocouples. Measures thermocouple output voltage as function of position of probe along sharp gradient of temperature. Abnormal variations in voltage-versus-position data indicative of Seebeck inhomogeneities. Prototype for development of standard method and equipment for routine acceptance/rejection testing of sheathed thermocouples in industrial and research laboratories.

  7. Probe with integrated heater and thermocouple pack

    DOEpatents

    McCulloch, Reginald W.; Dial, Ralph E.; Finnell, Wilber K. R.

    1988-01-01

    A probe for measuring heat includes an elongate rod fitted within a sheath, and a plurality of annular recesses are formed on the surface of the rod in a spaced-apart relationship to form annular chambers that are resistant to heat flow. A longitudinal bore extends axially into the rod and within the cylinders defined by the annular chambers, and an integrated heater and thermocouple pack is dimensioned to fit within the bore. In construction, the integrated pack includes a plurality of wires disposed in electrical insulation within a sheath and a heater cable. These wires include one common wire and a plurality of thermocouple wires. The common wire is constructed of one type of conductive material while the thermocouple wires are each constructed of two types of materials so that at least one thermocouple junction is formed therein. All of the wires extend the length of the integrated pack and are connected together at their ends. The thermocouple wires are constructed to form thermocouple junctions proximate to each annular chamber for producing electromotive forces corresponding to the temperature of the rod within the annular chambers relative to outside the chambers. In the preferred embodiment, each thermocouple wire forms two thermocouple junctions, one junction being disposed within an annular chamber and the second junction being disposed outside of, but proximate to, the same annular chamber. In one embodiment two thermocouple wires are configured to double the sensitivity of the probe in one region.

  8. Improvement of COBRA-TF for modeling of PWR cold- and hot-legs during reactor transients

    NASA Astrophysics Data System (ADS)

    Salko, Robert K.

    capture of more advanced physics in the coolant-line that can be expected during Loss-of-Coolant Accident. One of the package's benefits is its ability to be used as a platform for future coolant-line model development and implementation, including capturing of the important de-entrainment behavior in reactor hot-legs (steam-binding effect) and flow convection in the upper-plenum region of the vessel.

  9. Probe with integrated heater and thermocouple pack

    SciTech Connect

    McCulloch, R.W.; Dial, R.E.; Finnell, W.F.R.

    1988-02-16

    This patent describes a gamma thermometer probe for detecting heat produced within the thermometer probe. It comprises: an outer elongate thermometer sheath; an elongate rod; annular recesses; a longitudinal bore; and an integrated thermocouple pack. The thermocouple pack comprises: a first type wire, and second type wires. The second type wires comprises: an outer section; and an inner segment.

  10. Probe with integrated heater and thermocouple pack

    DOEpatents

    McCulloch, Reg W.; Dial, Ralph E.; Finnell, Wilber K. R.

    1990-01-01

    A probe for measuring heat includes an elongate rod fitted within a sheath, and a plurality of annular recesses are formed on the surface of the rod in a spaced-apart relationship to form annular chambers that are resistant to heat flow. A longitudinal bore extends axially into the rod and within the cylinders defined by the annular chambers, and an integrated heater and thermocouple pack is dimensioned to fit within the bore. In construction, the integrated pack includes a plurality of wires disposed in electrical insulation within a sheath and a heater cable. These wires include one common wire and a plurality of thermocuple wires. The common wire is constructed of one type of conductive material while the thermocouple wires are each constructed of two types of materials so that at least one thermocouple junction is formed therein. All of the wires extend the length of the integrated pack and are connected together at their ends. The thermocouple wires are constructed to form thermocouple junctions proximate to each annular chamber for producing electromotive forces corresponding to the temperature of the rod within the annular chambers relative to outside the chambers. In the preferred embodiment, each thermocouple wire forms two thermocouple junctions, one junction being disposed within an annular chamber and the second junction being disposed outside of, but proximate to, the same annular chamber. In one embodiment two thermocouple wires are configured to double the sensitivity of the probe in one region.

  11. Attaching Thermocouples by Peening or Crimping

    NASA Technical Reports Server (NTRS)

    Murtland, Kevin; Cox, Robert; Immer, Christopher

    2006-01-01

    Two simple, effective techniques for attaching thermocouples to metal substrates have been devised for high-temperature applications in which attachment by such conventional means as welding, screws, epoxy, or tape would not be effective. The techniques have been used successfully to attach 0.005- in. (0.127-mm)-diameter type-S thermocouples to substrates of niobium alloy C-103 and stainless steel 416 for measuring temperatures up to 2,600 F (1,427 C). The techniques are equally applicable to other thermocouple and substrate materials. In the first technique, illustrated in the upper part of the figure, a hole slightly wider than twice the diameter of one thermocouple wire is drilled in the substrate. The thermocouple is placed in the hole, then the edge of the hole is peened in one or more places by use of a punch (see figure). The deformed material at the edge secures the thermocouple in the hole. In the second technique a hole is drilled as in the first technique, then an annular relief area is machined around the hole, resulting in structure reminiscent of a volcano in a crater. The thermocouple is placed in the hole as in the first technique, then the "volcano" material is either peened by use of a punch or crimped by use of sidecutters to secure the thermocouple in place. This second technique is preferable for very thin thermocouples [wire diameter .0.005 in. (.0.127 mm)] because standard peening poses a greater risk of clipping one or both of the thermocouple wires. These techniques offer the following advantages over prior thermocouple-attachment techniques: . Because these techniques involve drilling of very small holes, they are minimally invasive . an important advantage in that, to a first approximation, the thermal properties of surrounding areas are not appreciably affected. . These techniques do not involve introduction of any material, other than the substrate and thermocouple materials, that could cause contamination, could decompose, or oxidize

  12. Improving thermocouple service life in slagging gasifiers

    SciTech Connect

    Bennett, James P.; Kwong, Kyei-Sing; Powell, Cynthia A.; Thomas, Hugh; Krabbe, Rick

    2005-01-01

    The measurement of temperature within slagging gasifiers for long periods of time is difficult/impossible because of sensor failure or blockage of inputs used to monitor gasifier temperature. One of the most common means of temperature measurement in a gasifier is physically, through the use of thermocouples in a gasifier sidewall. These units can fail during startup, standby, or during the first 40-90 days of gasifier service. Failure can be caused by a number of issues; including thermocouple design, construction, placement in the gasifier, gasifier operation, and molten slag attack of the materials used in a thermocouple assembly. Lack of temperature control in a gasifier can lead to improper preheating, slag buildup on gasifier sidewalls, slag attack of gasifier refractories used to line a gasifier, or changes in desired gas output from a gasifier. A general outline of thermocouple failure issues and attempts by the Albany Research Center to improve the service life of thermocouples will be discussed.

  13. Using self-calibrating thermocouples in industry

    SciTech Connect

    Ruppel, F.R.

    1989-01-01

    The self-calibrating thermocouple is a thermocouple with a low melting point, high-purity metal encapsulated near but metallurgically isolated from its thermojunction. It is designed to provide a single-point calibration of the thermocouple at the melting point of the encapsulated metal because the time-temperature curve of the thermocouple will plateau at this temperature during heating or cooling. The calibration procedure consists of comparing the plateau temperature with the known melting point temperature of the encapsulated metal. The difference between these two values is the thermocouple error at the calibration point. The device is commercially available, but to be effective in industry it must be augmented with a data acquisition system with an algorithm that will automatically report the calibration error. 5 refs., 7 figs.

  14. AGR-1 Thermocouple Data Analysis

    SciTech Connect

    Jeff Einerson

    2012-05-01

    This report documents an effort to analyze measured and simulated data obtained in the Advanced Gas Reactor (AGR) fuel irradiation test program conducted in the INL's Advanced Test Reactor (ATR) to support the Next Generation Nuclear Plant (NGNP) R&D program. The work follows up on a previous study (Pham and Einerson, 2010), in which statistical analysis methods were applied for AGR-1 thermocouple data qualification. The present work exercises the idea that, while recognizing uncertainties inherent in physics and thermal simulations of the AGR-1 test, results of the numerical simulations can be used in combination with the statistical analysis methods to further improve qualification of measured data. Additionally, the combined analysis of measured and simulation data can generate insights about simulation model uncertainty that can be useful for model improvement. This report also describes an experimental control procedure to maintain fuel target temperature in the future AGR tests using regression relationships that include simulation results. The report is organized into four chapters. Chapter 1 introduces the AGR Fuel Development and Qualification program, AGR-1 test configuration and test procedure, overview of AGR-1 measured data, and overview of physics and thermal simulation, including modeling assumptions and uncertainties. A brief summary of statistical analysis methods developed in (Pham and Einerson 2010) for AGR-1 measured data qualification within NGNP Data Management and Analysis System (NDMAS) is also included for completeness. Chapters 2-3 describe and discuss cases, in which the combined use of experimental and simulation data is realized. A set of issues associated with measurement and modeling uncertainties resulted from the combined analysis are identified. This includes demonstration that such a combined analysis led to important insights for reducing uncertainty in presentation of AGR-1 measured data (Chapter 2) and interpretation of

  15. Side-welded fast response sheathed thermocouple

    DOEpatents

    Carr, K.R.

    A method of fabricating the measuring junction of a grounded-junction sheathed thermocouple to obtain fast time response and good thermal cycling performance is provided. Slots are tooled or machined into the sheath wall at the measuring junction, the thermocouple wires are laser-welded into the slots. A thin metal closure cap is then laser-welded over the end of the sheath. Compared to a conventional grounded-junction thermocouple, the response time is 4 to 5 times faster and the thermal shock and cycling capabilities are substantially improved.

  16. Side-welded fast response sheathed thermocouple

    DOEpatents

    Carr, Kenneth R.

    1981-01-01

    A method of fabricating the measuring junction of a grounded-junction sheathed thermocouple to obtain fast time response and good thermal cycling performance is provided. Slots are tooled or machined into the sheath wall at the measuring junction, the thermocouple wires are laser-welded into the slots. A thin metal closure cap is then laser-welded over the end of the sheath. Compared to a conventional grounded-junction thermocouple, the response time is 4-5 times faster and the thermal shock and cycling capabilities are substantially improved.

  17. Gold ink coating of thermocouple sheaths

    DOEpatents

    Ruhl, H. Kenneth

    1992-01-01

    A method is provided for applying a gold ink coating to a thermocouple sheath which includes the steps of electropolishing and oxidizing the surface of the thermocouple sheath, then dipping the sheath into liquid gold ink, and finally heat curing the coating. The gold coating applied in this manner is highly reflective and does not degrade when used for an extended period of time in an environment having a temperature over 1000.degree. F. Depending on the application, a portion of the gold coating covering the tip of the thermocouple sheath is removed by abrasion.

  18. Connecting to Thermocouples with Fewer Lead Wires

    NASA Technical Reports Server (NTRS)

    Goldsby, Jon C.

    2003-01-01

    A simple technique has been devised to reduce the number of lead wires needed to connect an array of thermocouples to the instruments (e.g., voltmeters) used to read their output voltages. Because thermocouple wires are usually made of expensive metal alloys, reducing the number of lead wires can effect a considerable reduction in the cost of such an array. Reducing the number of wires also reduces the number of terminals and the amount of space needed to accommodate the wires.

  19. Tubular electric heater with a thermocouple assembly

    DOEpatents

    House, R.K.; Williams, D.E.

    1975-08-01

    This patent relates to a thermocouple or other instrumentation which is installed within the walls of a tubular sheath surrounding a process device such as an electric heater. The sheath comprises two concentric tubes, one or both of which have a longitudinal, concave crease facing the other tube. The thermocouple is fixedly positioned within the crease and the outer tube is mechanically reduced to form an interference fit onto the inner tube. (auth)

  20. Broken Leg

    MedlinePlus

    ... through — like when you try to break a green stick of wood. Most broken bones in children ... subside before they are casted. Immobilization Restricting the movement of a broken bone in your leg is ...

  1. Welding Wires To Thin Thermocouple Films

    NASA Technical Reports Server (NTRS)

    Holanda, Raymond; Kim, Walter S.; Danzey, Gerald A.; Pencil, Eric; Wadel, Mary

    1993-01-01

    Parallel-gap resistance welding yields joints surviving temperatures of about 1,000 degrees C. Much faster than thermocompression bonding. Also exceeds conductive-paste bonding and sputtering thin films through porous flame-sprayed insulation on prewelded lead wires. Introduces no foreign material into thermocouple circuit and does not require careful control of thickness of flame-sprayed material.

  2. A thermocouple thermode for small animals

    NASA Technical Reports Server (NTRS)

    Williams, B. A.

    1972-01-01

    Thermode composed of two thin-walled stainless steel hypodermic needles and cooper-constantan thermocouple or small thermistor to indicate temperature at point of perfusion is used to measure brain temperature in animals. Because of relatively small size of thermode, structural damage to brain is minimized.

  3. Semiconductor cooling by thin-film thermocouples

    NASA Technical Reports Server (NTRS)

    Tick, P. A.; Vilcans, J.

    1970-01-01

    Thin-film, metal alloy thermocouple junctions do not rectify, change circuit impedance only slightly, and require very little increase in space. Although they are less efficient cooling devices than semiconductor junctions, they may be applied to assist conventional cooling techniques for electronic devices.

  4. Thermocouple for heating and cooling of memory metal actuators

    NASA Technical Reports Server (NTRS)

    Wood, Charles (Inventor)

    1988-01-01

    A semiconductor thermocouple unit is provided for heating and cooling memory metal actuators. The semiconductor thermocouple unit is mounted adjacent to a memory metal actuator and has a heat sink attached to it. A flexible thermally conductive element extends between the semiconductor thermocouple and the actuator and serves as a heat transfer medium during heating and cooling operations.

  5. A preliminary study of factors affecting the calibration stability of the iridium versus iridium-40 percent rhodium thermocouple

    NASA Technical Reports Server (NTRS)

    Ahmed, Shaffiq; Germain, Edward F.; Daryabeigi, Kamran; Alderfer, David W.; Wright, Robert E.

    1987-01-01

    An iridium versus iridium-40% rhodium thermocouple was studied. Problems associated with the use of this thermocouple for high temperature applications (up to 2000 C) were investigated. The metallurgical studies included X-ray, macroscopic, resistance, and metallographic studies. The thermocouples in the as-received condition from the manufacturer revealed large amounts of internal stress caused by cold working during manufacturing. The thermocouples also contained a large amount of inhomogeneities and segregations. No phase transformations were observed in the alloy up to 1100 C. It was found that annealing the thermocouple at 1800 C for two hours, and then at 1400 C for 2 to 3 hours yielded a fine grain structure, relieving some of the strains, and making the wire more ductile. It was also found that the above annealing procedure stabilized the thermal emf behavior of the thermocouple for application below 1800 C (an improvement from + or - 1% to + or - 0.02% within the range of the test parameters used).

  6. Leg Problems

    MedlinePlus

    ... your lower leg that may have started after physical activity such as running or jumping?YesNoDo you have pain, swelling, redness or warmth in your calf?YesNoDo you have twisted dark blue or purple veins near the surface of the skin of your calf, and do you have pain ...

  7. Computer program for pulsed thermocouples with corrections for radiation effects

    NASA Technical Reports Server (NTRS)

    Will, H. A.

    1981-01-01

    A pulsed thermocouple was used for measuring gas temperatures above the melting point of common thermocouples. This was done by allowing the thermocouple to heat until it approaches its melting point and then turning on the protective cooling gas. This method required a computer to extrapolate the thermocouple data to the higher gas temperatures. A method that includes the effect of radiation in the extrapolation is described. Computations of gas temperature are provided, along with the estimate of the final thermocouple wire temperature. Results from tests on high temperature combustor research rigs are presented.

  8. Frequency response in short thermocouple wires

    NASA Technical Reports Server (NTRS)

    Forney, L. J.; Meeks, E. L.; Ma, J.; Fralick, G. C.

    1992-01-01

    Theoretical expressions are derived for the steady state frequency response of a thermocouple wire. In particular, the effects of axial heat conduction are demonstrated for a nonuniform wire with unequal material properties and wire diameters across the junction. The amplitude ratio at low frequency omega approaches 0 agrees with the results of Scadron and Warshawsky (1952) for a steady state temperature distribution. Moreover, the frequency response for a nonuniform wire in the limit of infinite length l approaches infinity is shown to reduce to a simple expression that is analogous to the classic first order solution for a thermocouple wire with uniform properties. Theoretical expressions are also derived for the steady state frequency response of a supported thermocouple wire. In particular, the effects of axial heat conduction are demonstrated for both a supported one material wire and a two material wire with unequal material properties across the junction. For the case of a one material supported wire, an exact solution is derived which compares favorably with an approximate expression that only matches temperatures at the support junction. Moreover, for the case of a two material supported wire, an analytical expression is derived that closely correlates numerical results. Experimental measurements are made for the steady state frequency response of a supported thermocouple wire. In particular, the effects of axial heat conduction are demonstrated for both a supported one material wire (type K) and a two material wire (type T) with unequal material properties across the junction. The data for the amplitude ratio and phase angle are correlated to within 10 pct. with the theoretical predictions of Forney and Fralick (1991). This is accomplished by choosing a natural frequency omega sub n for the wire data to correlate the first order response at large gas temperature frequencies. It is found that a large bead size, however, will increase the amplitude ratio at

  9. Leg CT scan

    MedlinePlus

    CAT scan - leg; Computed axial tomography scan - leg; Computed tomography scan - leg; CT scan - leg ... scanners can perform the exam without stopping.) A computer creates separate images of the body area, called ...

  10. Protective sheath for a continuous measurement thermocouple

    SciTech Connect

    Phillippi, R. Michael

    1991-01-01

    Disclosed is a protective thermocouple sheath of a magnesia graphite refractory material for use in continuous temperature measurements of molten metal in a metallurgical ladle and having a basic slag layer thereon. The sheath includes an elongated torpedo-shaped sheath body formed of a refractory composition and having an interior borehole extending axially therethrough and adapted to receive a thermocouple. The sheath body includes a lower end which is closed about the borehole and forms a narrow, tapered tip. The sheath body also includes a first body portion integral with the tapered tip and having a relatively constant cross section and providing a thin wall around the borehole. The sheath body also includes a second body portion having a relatively constant cross section larger than the cross section of the first body portion and providing a thicker wall around the borehole. The borehole terminates in an open end at the second body portion. The tapered tip is adapted to penetrate the slag layer and the thicker second body portion and its magnesia constituent material are adapted to withstand chemical attack thereon from the slag layer. The graphite constituent improves thermal conductivity of the refractory material and, thus, enhances the thermal responsiveness of the device.

  11. Protective sheath for a continuous measurement thermocouple

    SciTech Connect

    Phillippi, R.M.

    1991-12-03

    Disclosed is a protective thermocouple sheath of a magnesia graphite refractory material for use in continuous temperature measurements of molten metal in a metallurgical ladle and having a basic slag layer thereon. The sheath includes an elongated torpedo-shaped sheath body formed of a refractory composition and having an interior borehole extending axially therethrough and adapted to receive a thermocouple. The sheath body includes a lower end which is closed about the borehole and forms a narrow, tapered tip. The sheath body also includes a first body portion integral with the tapered tip and having a relatively constant cross section and providing a thin wall around the borehole. The sheath body also includes a second body portion having a relatively constant cross section larger than the cross section of the first body portion and providing a thicker wall around the borehole. The borehole terminates in an open end at the second body portion. The tapered tip is adapted to penetrate the slag layer and the thicker second body portion and its magnesia constituent material are adapted to withstand chemical attack thereon from the slag layer. The graphite constituent improves thermal conductivity of the refractory material and, thus, enhances the thermal responsiveness of the device. 4 figures.

  12. Sea Legs

    NASA Astrophysics Data System (ADS)

    Macdonald, Kenneth C.

    Forty-foot, storm-swept seas, Spitzbergen polar bears roaming vast expanses of Arctic ice, furtive exchanges of forbidden manuscripts in Cold War Moscow, the New York city fashion scene, diving in mini-subs to the sea floor hot srings, life with the astronauts, romance and heartbreak, and invading the last bastions of male exclusivity: all are present in this fast-moving, non-fiction account of one woman' fascinating adventures in the world of marine geology and oceanography.

  13. Peripheral artery disease - legs

    MedlinePlus

    ... legs; Arterial insufficiency of the legs; Recurrent leg pain and cramping; Calf pain with exercise ... The main symptoms of PAD are pain, achiness, fatigue, burning, or ... or thighs. These symptoms most often appear during walking or ...

  14. Thermocouple Extension-Wire-Connections and Low Temperatures

    NASA Technical Reports Server (NTRS)

    Figueroa, Fernando; Mitchell, Mark; Richardson, Gregory

    2000-01-01

    Experiments were carried out to determine the casue of erroneous readings from thermocouples of type K when measuring temperatures of liquid hydrogen. It was believed to be linked to te temperature of the connector used to extend the thermocouple wires to the voltage meter.

  15. Automatic thermocouple positioner for use in vacuum furnaces

    DOEpatents

    Mee, D.K.; Stephens, A.E.

    1980-06-06

    The invention is a simple and reliable mechanical arrangement for automatically positioning a thermocouple-carrying rod in a vacuum-furnace assembly of the kind including a casing, a furnace mounted in the casing, and a charge-containing crucible mounted in the furnace for vertical movement between a lower (loading) position and a raised (charge-melting) position. In a preferred embodiment, a welded-diaphragm metal bellows is mounted above the furnace, the upper end of the bellows being fixed against movement and the lower end of the bellows being affixed to support means for a thermocouple-carrying rod which is vertically oriented and extends freely through the furnace lid toward the mouth of the crucible. The support means and rod are mounted for relative vertical movement. Before pumpdown of the furnace, the differential pressure acting on the bellows causes it to contract and lift the thermocouple rod to a position where it will not be contacted by the crucible charge when the crucible is elevated to its raised position. During pumpdown, the bellows expands downward, lowering the thermocouple rod and its support. The bellows expands downward beyond a point where downward movement of the thermocouple rod is arrested by contact with the crucible charge and to a point where the upper end of the thermocouple extends well above the thermocouple support. During subsequent melting of the charge, the thermocouple sinks into the melt to provide an accurate measurement of melt temperatures.

  16. Automatic thermocouple positioner for use in vacuum furnaces

    DOEpatents

    Mee, David K.; Stephens, Albert E.

    1981-01-01

    The invention is a simple and reliable mechanical arrangement for automatically positioning a thermocouple-carrying rod in a vacuum-furnace assembly of the kind including a casing, a furnace mounted in the casing, and a charge-containing crucible mounted in the furnace for vertical movement between a lower (loading) position and a raised (charge-melting) position. In a preferred embodiment, a welded-diaphragm metal bellows is mounted above the furnace, the upper end of the bellows being fixed against movement and the lower end of the bellows being affixed to support means for a thermocouple-carrying rod which is vertically oriented and extends freely through the furnace lid toward the mouth of the crucible. The support means and rod are mounted for relative vertical movement. Before pumpdown of the furnace, the differential pressure acting on the bellows causes it to contract and lift the thermocouple rod to a position where it will not be contacted by the crucible charge when the crucible is elevated to its raised position. During pumpdown, the bellows expands downward, lowering the thermocouple rod and its support. The bellows expands downward beyond a point where downward movement of the thermocouple rod is arrested by contact with the crucible charge and to a point where the upper end of the thermocouple extends well above the thermocouple support. During subsequent melting of the charge, the thermocouple sinks into the melt to provide an accurate measurement of melt temperatures.

  17. Thin film thermocouples for high temperature measurement on ceramic materials

    NASA Technical Reports Server (NTRS)

    Holanda, Raymond

    1992-01-01

    Thin film thermocouples have been developed for use on metal parts in jet engines to 1000 C. However, advanced propulsion systems are being developed that will use ceramic materials and reach higher temperatures. The purpose of this work is to develop thin film thermocouples for use on ceramic materials. The thin film thermocouples are Pt13Rh/Pt fabricated by the sputtering process. Lead wires are attached using the parallel-gap welding process. The ceramic materials are silicon nitride, silicon carbide, aluminum oxide, and mullite. Both steady state and thermal cycling furnace tests were performed in the temperature range to 1500 C. High-heating-rate tests were performed in an arc lamp heat-flux-calibration facility. The fabrication of the thin film thermocouples is described. The thin film thermocouple output was compared to a reference wire thermocouple. Drift of the thin film thermocouples was determined, and causes of drift are discussed. The results of high-heating-rate tests up to 2500 C/sec are presented. The stability of the ceramic materials is examined. It is concluded that Pt13Rh/Pt thin film thermocouples are capable of meeting lifetime goals of 50 hours or more up to temperatures of 1500 C depending on the stability of the particular ceramic substrate.

  18. Base metal thermocouples drift rate dependence from thermoelement diameter

    NASA Astrophysics Data System (ADS)

    Pavlasek, P.; Duris, S.; Palencar, R.

    2015-02-01

    Temperature measurements are one of the key factors in many industrial applications that directly affect the quality, effectiveness and safety of manufacturing processes. In many industrial applications these temperature measurements are realized by thermocouples. Accuracy of thermocouples directly affects the quality of the final product of manufacturing and their durability determines the safety margins required. One of the significant effects that affect the precision of the thermocouples is short and long term stability of their voltage output. This stability issue occurs in every type of thermocouples and is caused by multiple factors. In general these factors affect the Seebeck coefficient which is a material constant, which determines the level of generated voltage when exposed to a temperature gradient. Changes of this constant result in the change of the thermocouples voltage output thus indicated temperature which can result in production quality issues, safety and health hazards. These alternations can be caused by physical and chemical changes within the thermocouple lead material. Modification of this material constant can be of temporary nature or permanent. This paper concentrates on the permanent, or irreversible changes of the Seebeck coefficient that occur in commonly used swaged MIMS Type N thermocouples. These permanent changes can be seen as systematic change of the EMF of the thermocouple when it is exposed to a high temperature over a period of time. This change of EMF by time is commonly known as the drift of the thermocouple. This work deals with the time instability of thermocouples EMF at temperatures above 1200 °C. Instability of the output voltage was taken into relation with the lead diameter of the tested thermocouples. This paper concentrates in detail on the change of voltage output of thermocouples of different diameters which were tested at high temperatures for the overall period of more than 210 hours. The gather data from this

  19. Probe with integrated heater and thermocouple pack

    SciTech Connect

    McCulloch, R.W.; Dial, R.E.; Finnell, W.R.

    1988-02-16

    A gamma thermometer probe for detecting heat produced within the thermometer probe is described comprising: an outer elongate thermometer sheath having a cylindrical cross-section, a length, an outer end and an inner end; an elongate rod having a cylindrical cross-section fitted within the elongate thermometer sheath, the rod being constructed of material that absorbs radiation and produces heat; annular recesses formed between the rod, and sheath and being spaced apart along the length of the rod, the recesses forming annular chambers that are resistive to heat flow; a longitudinal bore extending axially into the rod and being positioned to extend through the cylinders defined by the annular chambers; and an integrated thermocouple pack dimensioned to fit within the longitudinal bore and extending through the cylinders defined by the annular chambers.

  20. Evaluation of disinfection techniques for, and their effects on, rectal thermocouple catheters.

    PubMed

    MAHER, J T; ROGERS, M R; PETERSON, D W

    1961-07-01

    The antibacterial activities of an iodophor (Wescodyne G), a quaternary ammonium compound (Roccal), and an iodine tincture as agents for the cold disinfection of rectal catheters contaminated in vitro were determined. Following thorough cleaning with an alcoholic solution of soft soap, each of the three disinfectants tested showed satisfactory results (100% kill) in 5 min against the enteric test bacteria (Escherichia coli and Salmonella typhosa) as well as a test species of the genus Pseudomonas, among the bacteria most resistant to surface-active agents. An aqueous solution of Wescodyne G containing 75 ppm available iodine was used both as a wiping solution and for subsequent disinfection of rectal catheters contaminated in vivo. Total bacterial destruction was found to follow a 60-min soak preceded by the wiping procedure. Rectal catheters subjected to prolonged immersion in each of the test disinfectants were found to be essentially unaffected, retaining their initial calibrations within a permissible tolerance. Neither Roccal nor Wescodyne G solutions were found to measurably attack bare thermocouples. Alcoholic iodine 0.5% did, however, exert a deteriorating effect on bare thermocouples in a short time, as measured by change in resistance characteristics. The results of this study have led to the recommendation that Wescodyne G containing 75 ppm available iodine be used in standing operating procedures for the initial cleaning and subsequent disinfection of rectal thermocouple catheters.

  1. Quantifying the calibration uncertainty attributable to thermocouple inhomogeneity

    NASA Astrophysics Data System (ADS)

    Hill, K. D.; Gee, D. J.

    2013-09-01

    Inhomogeneity in the Seebeck coefficient as a function of position along a thermocouple wire frequently dominates the uncertainty budgets of thermocouple calibration and use. The calibration process itself, simply through exposure to elevated temperatures for relatively modest times, generates both reversible and irreversible changes to the thermocouple that are a complex function of time, temperature, alloy composition, sheath structure, etc. We present data acquired using a salt bath at 250 °C to provide the step-function-like gradient that is our spatial probe of thermoelectric homogeneity. We show how the finite width of the step-function limits our ability to assess the "true" inhomogeneity of the thermocouple, and explore how the inhomogeneity impacts the calibration uncertainty attainable with the various thermal sources used for the calibration of thermocouples (based on their characteristic temperature gradients).

  2. Metallic and Ceramic Thin Film Thermocouples for Gas Turbine Engines

    PubMed Central

    Tougas, Ian M.; Amani, Matin; Gregory, Otto J.

    2013-01-01

    Temperatures of hot section components in today's gas turbine engines reach as high as 1,500 °C, making in situ monitoring of the severe temperature gradients within the engine rather difficult. Therefore, there is a need to develop instrumentation (i.e., thermocouples and strain gauges) for these turbine engines that can survive these harsh environments. Refractory metal and ceramic thin film thermocouples are well suited for this task since they have excellent chemical and electrical stability at high temperatures in oxidizing atmospheres, they are compatible with thermal barrier coatings commonly employed in today's engines, they have greater sensitivity than conventional wire thermocouples, and they are non-invasive to combustion aerodynamics in the engine. Thin film thermocouples based on platinum:palladium and indium oxynitride:indium tin oxynitride as well as their oxide counterparts have been developed for this purpose and have proven to be more stable than conventional type-S and type-K thin film thermocouples. The metallic and ceramic thin film thermocouples described within this paper exhibited remarkable stability and drift rates similar to bulk (wire) thermocouples. PMID:24217356

  3. Applications of Thin Film Thermocouples for Surface Temperature Measurement

    NASA Technical Reports Server (NTRS)

    Martin, Lisa C.; Holanda, Raymond

    1994-01-01

    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, therefore 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 percent rhodium versus 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.

  4. Metallic and ceramic thin film thermocouples for gas turbine engines.

    PubMed

    Tougas, Ian M; Amani, Matin; Gregory, Otto J

    2013-11-08

    Temperatures of hot section components in today's gas turbine engines reach as high as 1,500 °C, making in situ monitoring of the severe temperature gradients within the engine rather difficult. Therefore, there is a need to develop instrumentation (i.e., thermocouples and strain gauges) for these turbine engines that can survive these harsh environments. Refractory metal and ceramic thin film thermocouples are well suited for this task since they have excellent chemical and electrical stability at high temperatures in oxidizing atmospheres, they are compatible with thermal barrier coatings commonly employed in today's engines, they have greater sensitivity than conventional wire thermocouples, and they are non-invasive to combustion aerodynamics in the engine. Thin film thermocouples based on platinum:palladium and indium oxynitride:indium tin oxynitride as well as their oxide counterparts have been developed for this purpose and have proven to be more stable than conventional type-S and type-K thin film thermocouples. The metallic and ceramic thin film thermocouples described within this paper exhibited remarkable stability and drift rates similar to bulk (wire) thermocouples.

  5. Leg Injuries and Disorders

    MedlinePlus

    ... legs. Common leg injuries include sprains and strains, joint dislocations, and fractures. These injuries can affect the entire leg, or just the foot, ankle, knee, or hip. Certain diseases also lead to leg problems. For example, knee osteoarthritis, common in older people, can cause pain and ...

  6. Development of Thin Film Ceramic Thermocouples for High Temperature Environments

    NASA Technical Reports Server (NTRS)

    Wrbanek, John D.; Fralick, Gustave C.; Farmer, Serene C.; Sayir, Ali; Blaha, Charles A.; Gonzalez, Jose M.

    2004-01-01

    The maximum use temperature of noble metal thin film thermocouples of 1100 C (2000 F) may not be adequate for use on components in the increasingly harsh conditions of advanced aircraft and next generation launch technology. Ceramic-based thermocouples are known for their high stability and robustness at temperatures exceeding 1500 C, but are typically found in the form of rods or probes. NASA Glenn Research Center is investigating the feasibility of ceramics as thin film thermocouples for extremely high temperature applications to take advantage of the stability and robustness of ceramics and the non-intrusiveness of thin films. This paper will discuss the current state of development in this effort.

  7. Thermocouple Calibration and Accuracy in a Materials Testing Laboratory

    NASA Technical Reports Server (NTRS)

    Lerch, B. A.; Nathal, M. V.; Keller, D. J.

    2002-01-01

    A consolidation of information has been provided that can be used to define procedures for enhancing and maintaining accuracy in temperature measurements in materials testing laboratories. These studies were restricted to type R and K thermocouples (TCs) tested in air. Thermocouple accuracies, as influenced by calibration methods, thermocouple stability, and manufacturer's tolerances were all quantified in terms of statistical confidence intervals. By calibrating specific TCs the benefits in accuracy can be as great as 6 C or 5X better compared to relying on manufacturer's tolerances. The results emphasize strict reliance on the defined testing protocol and on the need to establish recalibration frequencies in order to maintain these levels of accuracy.

  8. Self-replaceable thermocouple for molten steel bath - A concept

    NASA Technical Reports Server (NTRS)

    Blau, P.; Zellner, G.

    1971-01-01

    Thermocouple wires, consisting of tungsten-rhenium alloy protected by ablative ceramic coating, are wound on a reel and fed continuously into bath. Tests indicate accuracy and reliability are comparable to conventional devices.

  9. SP-100 W/Re thermocouple calibration techniques

    SciTech Connect

    Cannon, N.S.; Knight, R.C.

    1992-01-01

    The accuracy requirement of the SP-100 Temperature Sensor Program for the reference tungsten/rhenium metal-sheathed thermocouple sensor is {plus minus}1.4% of the reading (in Kelvin) at space reactor operating temperature (nominally 1375 K) over the operating life of the reactor. This is a stringent requirement considering that the as-fabricated base wire limits of error'' are generally specified at roughly {plus minus}1.0% for exposure temperatures above 700 K. Although the thermocouples will be located out of the reactor's neutron field so that irradiation decalibration is expected to be negligible, thermal exposure effects will probably cause the thermocouple to drift out of specification during the 10-yr reactor operating life. A plan to accurately quantify thermocouple drift with aging time, and thus provide on-board calibration for the sensor is described.

  10. High Temperature Irradiation Resistant Thermocouple (HTIR-TC)

    SciTech Connect

    2011-01-01

    INL researchers have created a new thermocouple that can resist high temperature and radiation. This device will improve safety and reduce costs associated with unit failures. Learn more about INL research at http://www.facebook.com/idahonationallaboratory

  11. High Temperature Irradiation Resistant Thermocouple (HTIR-TC)

    ScienceCinema

    None

    2016-07-12

    INL researchers have created a new thermocouple that can resist high temperature and radiation. This device will improve safety and reduce costs associated with unit failures. Learn more about INL research at http://www.facebook.com/idahonationallaboratory

  12. Thin-Film Ceramic Thermocouples Fabricated and Tested

    NASA Technical Reports Server (NTRS)

    Wrbanek, John D.; Fralick, Gustave C.; Farmer, Serene C.; Sayir, Ali; Gregory, Otto J.; Blaha, Charles A.

    2004-01-01

    The Sensors and Electronics Technology Branch of the NASA Glenn Research Center is developing thin-film-based sensors for surface measurement in propulsion system research. Thin-film sensors do not require special machining of the components on which they are mounted, and they are considerably thinner than wire- or foil-based sensors. One type of sensor being advanced is the thin-film thermocouple, specifically for applications in high-temperature combustion environments. Ceramics are being demonstrated as having the potential to meet the demands of thin-film thermocouples in advanced aerospace environments. The maximum-use temperature of noble metal thin-film thermocouples, 1500 C (2700 F), may not be adequate for components used in the increasingly harsh conditions of advanced aircraft and next-generation launch vehicles. Ceramic-based thermocouples are known for their high stability and robustness at temperatures exceeding 1500 C, but are typically in the form of bulky rods or probes. As part of ASTP, Glenn's Sensors and Electronics Technology Branch is leading an in-house effort to apply ceramics as thin-film thermocouples for extremely high-temperature applications as part of ASTP. Since the purity of the ceramics is crucial for the stability of the thermocouples, Glenn's Ceramics Branch and Case Western Reserve University are developing high-purity ceramic sputtering targets for fabricating high-temperature sensors. Glenn's Microsystems Fabrication Laboratory, supported by the Akima Corporation, is using these targets to fabricate thermocouple samples for testing. The first of the materials used were chromium silicide (CrSi) and tantalum carbide (TaC). These refractory materials are expected to survive temperatures in excess of 1500 C. Preliminary results indicate that the thermoelectric voltage output of a thin-film CrSi versus TaC thermocouple is 15 times that of the standard type R (platinum-rhodium versus platinum) thermocouple, producing 20 mV with a 200

  13. Leg MRI scan

    MedlinePlus

    ... resonance imaging) scan of the leg uses strong magnets to create pictures of the leg. This may ... in your eyes) Because the MRI contains strong magnets, metal objects are not allowed into the room ...

  14. Design and Analysis of Novel Micromachined Thermocouples with Vertical Free-Standing High-Aspect-Ratio Geometry

    NASA Astrophysics Data System (ADS)

    Wick, M.; Hedler, H.; Seidel, H.

    2015-06-01

    This paper describes the design and analysis of free-standing three-dimensional (3D) thermocouples (TCs) for uncooled high-resolution infrared imaging. In contrast to the conventional horizontal thermocouple design, our 3D TCs consist of vertically oriented coaxial thermoelectric legs covered by an infrared absorber plate. The high aspect ratio of the 3D TCs of up to 100:1 leads to increased thermal resistance and, thus, higher electrical responsivity. Furthermore, reduced lateral dimensions of the device are achieved by coaxial mounting. This allows a closely packed arrangement of 3D TCs, which results in a high-resolution microarray sensor setup. These features represent the 3D TC's innovative uniqueness and open up new possibilities for further minimized uncooled thermal sensors and low-cost high-resolution imagers. We developed a fabrication process for 3D TCs with doped polysilicon as thermoelectric legs and a geometry with diameter of m and length of m. Performance analysis has been carried out using the lumped-heat-capacity method, resulting in an electrical responsivity and specific detectivity of a 3D TC of 383 V/W and cm /W, respectively.

  15. Irradiation testing of a niobium-molybdenum developmental thermocouple

    SciTech Connect

    Knight, R.C.; Greenslade, D.L.

    1991-10-01

    A need exists for a radiation-resistant thermocouple capable of monitoring temperatures in excess of the limits of the chromel/alumel system. Tungsten/rhenium and platinum/rhodium thermocouples have sufficient temperature capability but have proven to be unstable because of irradiation-induced decalibration. The niobium/molybdenum system is believed to hold great potential for nuclear applications at temperatures up to 2000 K. However, the fragility of pure niobium and fabrication problems with niobium/molybdenum alloys have limited development of this system. Utilizing the Fast Flux Test Facility, a developmental thermocouple with a thermoelement pair consisting of a pure molybdenum and a niobium-1%zirconium alloy wire was irradiated fro 7200 hours at a temperature of 1070 K. The thermocouple performed flawlessly for the duration of the experiment and exhibited stability comparable to a companion chromel/alumel unit. A second thermocouple, operating at 1375 K, is currently being employed to monitor a fusion materials experiment in the Fast Flux Test Facility. This experiment, also scheduled for 7200 hours, will serve to further evaluate the potential of the niobium-1%zirconium/molybdenum thermoelement system. 7 refs., 7 figs.

  16. Frequency response of a thermocouple wire: Effects of axial conduction

    NASA Technical Reports Server (NTRS)

    Forney, L. J.; Fralick, G. C.

    1990-01-01

    Theoretical expressions are derived for the steady-state frequency response of a thermocouple wire. In particular, the effects of axial heat conduction are demonstrated for both a uniform thermocouple wire and a nonuniform wire with unequal material properties and wire diameters across the junction. For the case of a uniform wire, the amplitude ratio and phase angle compare favorably with the series solution of Scadron and Warshawsky (1952) except near the ends of the wire. For the case of a non-uniform wire, the amplitude ratio at low frequency omega yields 0 agrees with the results of Scadron and Warshawsky for a steady-state temperature distribution. Moreover, the frequency response for a non-uniform wire in the limit of infinite length l yields infinity is shown to reduce to a simple expression that is analogous to the classic first order solution for a thermocouple wire with uniform properties.

  17. High Temperature Thermocouples For In-pile Applications

    SciTech Connect

    J. L. Rempe; S. C. Wilkins

    2005-10-01

    Traditional methods for measuring temperature in-pile degrade at temperatures above 1080 degrees C. Hence, a project has been initiated to explore the use of specialized thermocouples that are composed of materials that are able to withstand higher temperature, in-pile test conditions. Results from efforts to develop, fabricate and evaluate the performance of these specialized thermocouples are reported in this paper. Candidate materials were evaluated for their ability to withstand irradiation, to resit material interactions and to remain ductile at high temperatures. In addition, candidate thermocouples were evaluated based on their resolution over the temperature ranges of interest. Results from these evaluations are reported, and additional on-going development activities are summarized.

  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. Measurements of fluctuating gas temperatures using compensated fine wire thermocouples

    NASA Astrophysics Data System (ADS)

    Nina, M. N. R.; Pita, G. P.

    1985-09-01

    Thermocouples with three different wire diameters (15, 40 and 50 microns) were used in association with an analog compensation circuit connected to a data acquisition system. Measurements of the time constant were performed using two different heating techniques; Joule effect and external heating by laser beam. The thermocouples were used to quantify the fluctuating temperature field in a hot air jet and in a premixed propane flame. In the reacting case the catalytic effect was evaluated by comparing coated and uncoated wires. Conclusions were also obtained regarding frequency spectra, temperature probability distribution function and time constant.

  20. A calibration model for screen-caged Peltier thermocouple psychrometers

    NASA Astrophysics Data System (ADS)

    Brown, R. W.; Bartos, D. L.

    1982-07-01

    A calibration model for screen-caged Peltier thermocouple psychrometers was developed that applies to a water potential range of 0 to 80 bars, over a temperature range of 0 to 40 C, and for cooling times of 15 to 60 seconds. In addition, the model corrects for the effects of temperature gradients over zero-offsets from -60 to +60 microvolts. Complete details of model development are discussed, together with the theory of thermocouple psychrometers, and techniques of calibration and cleaning. Also, information for computer programing and tabular summaries of model characteristics are provided.

  1. Thermocouples For High Temperature In-Pile Testing

    SciTech Connect

    J. L. Rempe

    2005-11-01

    Many advanced nuclear reactor designs require new fuel, cladding and structural materials. Data are needed to characeterize the performance of these new materials in high temperature, oxidizing and radiation conditions. To obtain this data, robust instrumentation is needed htat can survive proposed test conditions. Traditional methods for measuring temperature in-pile degrade at temperatures above 1080 degrees C. Hence, a project was intiated to develop specialized thermocouples for high temperature in-pile applications (see Rempe and Wilkins, 2005). This paper summarizes efforts to develop, fabricate and evaluate these specialized thermocouples.

  2. Thermocouples of molybdenum and iridium alloys for more stable vacuum-high temperature performance

    NASA Technical Reports Server (NTRS)

    Morris, J. F. (Inventor)

    1978-01-01

    Thermocouples providing stability and performance reliability in systems involving high temperatures and vacuums by employing a bimetallic thermocouple sensor are described. Each metal of the sensor is selected from a group of metals comprising molybdenum and iridium and alloys containing only those two metals. The molybdenum, iridium thermocouple sensor alloys provide bare metal thermocouple sensors having advantageous vapor pressure compatibility and performance characteristics. The compatibility and physical characteristics of the thermocouple sensor alloys result in improved emf, temperature properties and thermocouple hot junction performance.

  3. A Comparison of Contemporary Gold Versus Platinum Thermocouples with NIST SRM 1749-Based Thermocouples and Reference Function

    NASA Astrophysics Data System (ADS)

    Coleman, M. J.; Wiandt, T. J.; Harper, T.

    2015-12-01

    Fluke Calibration (formerly Hart Scientific) in American Fork, Utah, USA is a manufacturer of temperature calibration instruments. The company manufactured reference standard gold versus platinum (Au-Pt) thermocouples from 1992 to about 2002. Manufacturing was halted in 2002 because a trend of poor curve-fit results was observed in new batches of wire. After reviewing the possible sources of the problem, it was decided to sample wire from multiple manufacturers and investigate ways to make the curve-fit work better. This paper presents the results from the study of the wire and a characterization technique to help improve characterization of thermocouples made with lower purity wire. Calibration results from NIST SRM material and older Fluke thermocouples are included as well to provide a means of comparison of contemporary wire to NIST SRM era wire.

  4. Management of leg ulcers

    PubMed Central

    Sarkar, P; Ballantyne, S

    2000-01-01

    Leg ulcer is a leading cause of morbidity among older subjects, especially women in the Western world. About 400 years BC, Hippocrates wrote, "In case of an ulcer, it is not expedient to stand, especially if the ulcer be situated on the leg". Hippocrates himself had a leg ulcer. The best treatment of any leg ulcer depends upon the accurate diagnosis and the underlying aetiology. The majority of leg ulcers are due to venous disease and/or arterial disease, but the treatment of the underlying cause is far more important than the choice of dressing. The aetiology, pathogenesis, treatment, and the future trends in the management of the leg ulcers are discussed in this review.
 PMID:11060140

  5. [Rapid freezing of biologic tissue. Measurement of temperature and rate of freezing by thin-layer thermocouple].

    PubMed

    Escaig, J; Géraud, G; Nicolas, G

    1977-06-13

    An apparatus for rapid freezing of biological tissues by contact with a copper block cooled by liquid helium has been devised to reduce the contamination of copper block surface. It prevents the precooling of the specimen while going through the layers of cold helium gas surrounding the copper block and reduces the quantity of helium necessary for freezing. It also enables one to obtain easily reproducible results from freezing by immersion in liquid coolants. Freezing rates are measured directly, related to the specimen thickness, by a thin film thermocouple; its low thermal inertia gives speed measurements of the order of 100,000 degrees C/s.

  6. Low-Cost Thermocouple Signal-Conditioning Module

    ERIC Educational Resources Information Center

    Lenzi, Marcelo K.; Silva, Fabricio M.; Lima, Enrique L.; Pinto, Jose Carlos; Cunningham, Michael F.

    2005-01-01

    It is well known that reaction rates and physical properties of any substance depend on the temperature. Therefore, an accurate temperature measurement is a key factor for successful activities both in chemical laboratories and industrial plants. Although plenty of sensors can be adopted for temperature measurements, thermocouples are the most…

  7. Thermocouples--The Most Widely Used Temperature Sensor in Manufacturing

    ERIC Educational Resources Information Center

    Mitts, Charles R.

    2006-01-01

    Researchers predict that future developments in nanotechnology will bring incredible, almost inconceivable, change to the manufacturing industry. For now, though, one of technology's most trusted tools remains very relevant: In the field of thermometry, thermocouples are a tried and true technology. As a consequence, material on thermocouples…

  8. High temperature thermocouple development program, part A and part B

    NASA Technical Reports Server (NTRS)

    Toenshoff, D. A.; Zysk, E. D.; Fleischner, P. L.

    1972-01-01

    The problem of extending the useful life of thermocouples intended for in-core and out-of-core thermionic applications in a vacuum environment at temperatures up to 2273 K for periods of time up to 10,000 hours was investigated. Many factors that may influence this useful life were examined, and a basic probe design was developed. With a few modifications, twenty-three thermocouple assemblies were fabricated. Generally the finished thermocouple consisted of solid doped W-3% Re and W-25% Re wires and high purity and high density BeO insulators, and was sheathed in a high purity tantalum tube. In a few probes, stranded thermocouple wires were substituted; commercial grade BeO was used; and in two cases, CVD W-22% Re tubing was used. Each of the components was made of the highest purity materials available; was subjected to special cleaning steps, and was assembled in a class 10,000 clean room. Pertinent physical and chemical properties were determined on each of the components. Special processing techniques were used in the fabrication of the high purity (99.95%), high density (over 95% of theoretical) BeO.

  9. A Multiple-range Self-balancing Thermocouple Potentiometer

    NASA Technical Reports Server (NTRS)

    Warshawsky, I; Estrin, M

    1951-01-01

    A multiple-range potentiometer circuit is described that provides automatic measurement of temperatures or temperature differences with any one of several thermocouple-material pairs. Techniques of automatic reference junction compensation, span adjustment, and zero suppression are described that permit rapid selection of range and wire material, without the necessity for restandardization, by setting of two external tap switches.

  10. Turbine blade metal temperature measurement with a sputtered thin film chromel-alumel thermocouple

    NASA Technical Reports Server (NTRS)

    Liebert, C. H.; Mazaris, G. A.; Brandhorst, H. W., Jr.

    1975-01-01

    A technique for fabricating Chromel and Alumel thin film thermocouples was developed. Turbine blade metal temperatures measured with the thin film thermocouple installation were compared with those of a reference sheathed (wire) thermocouple. Good agreement was obtained, and the results are encouraging.

  11. [Prevention of leg ulcer].

    PubMed

    Marinović Kulisić, Sandra

    2013-10-01

    Lower leg ulcers is the most common form of ulceration of the lower extremities. The prevalence of leg ulcer varies among studies from 0.1% to 0.6%. In the majority of studies, 1% of the population develop leg ulcer at least once in lifetime. The prevalence is higher in elderly people. There are several hypotheses used to explain the pathophysiological steps leading from the popliteal venous hypertension in value. Currently, the treatment of leg ulcer relies on due knowledge of ulcer pathophysiology and making an accurate diagnosis. Venous disease has a significant impact on quality of life and work productivity. In addition, costs associated with the prevention and treatment of lower leg ulcers are significant.

  12. Tungsten-rhenium thin film thermocouples for SiC-based ceramic matrix composites.

    PubMed

    Tian, Bian; Zhang, Zhongkai; Shi, Peng; Zheng, Chen; Yu, Qiuyue; Jing, Weixuan; Jiang, Zhuangde

    2017-01-01

    A tungsten-rhenium thin film thermocouple is designed and fabricated, depending on the principle of thermal-electric effect caused by the high temperature. The characteristics of thin film thermocouples in different temperatures are investigated via numerical analysis and analog simulation. The working mechanism and thermo-electric features of the thermocouples are analyzed depending on the simulation results. Then the thin film thermocouples are fabricated and calibrated. The calibration results show that the thin film thermocouples based on the tungsten-rhenium material achieve ideal static characteristics and work well in the practical applications.

  13. Tungsten-rhenium thin film thermocouples for SiC-based ceramic matrix composites

    NASA Astrophysics Data System (ADS)

    Tian, Bian; Zhang, Zhongkai; Shi, Peng; Zheng, Chen; Yu, Qiuyue; Jing, Weixuan; Jiang, Zhuangde

    2017-01-01

    A tungsten-rhenium thin film thermocouple is designed and fabricated, depending on the principle of thermal-electric effect caused by the high temperature. The characteristics of thin film thermocouples in different temperatures are investigated via numerical analysis and analog simulation. The working mechanism and thermo-electric features of the thermocouples are analyzed depending on the simulation results. Then the thin film thermocouples are fabricated and calibrated. The calibration results show that the thin film thermocouples based on the tungsten-rhenium material achieve ideal static characteristics and work well in the practical applications.

  14. Micro-thermocouple probe for measurement of cellular thermal responses.

    PubMed

    Watanabe, M; Kakuta, N; Mabuchi, K; Yamada, Y

    2005-01-01

    We have produced micro-thermocouple probes for the measurement of cellular thermal responses. Cells generate heat with their metabolisms and more heat with reactions to a certain physical or chemical stimulation. Therefore, the analysis of the cellular thermal responses would provide new physiological information. However, a real-time thermal measurement technique on a target of a single cell has not been established. In this study, glass micropipettes, which are widely used in bioengineering and medicine, are used for the base of the thermocouple probes. Using microfabrication techniques, the junction of two different metal films is formed at the micropipette tip with a diameter of 1 μm. This probe can inject a chemical substance into a cell and to detect its subsequent temperature changes simultaneously.

  15. Hysteresis Effects and Strain-Induced Homogeneity Effects in Base Metal Thermocouples

    NASA Astrophysics Data System (ADS)

    Pavlasek, P.; Elliott, C. J.; Pearce, J. V.; Duris, S.; Palencar, R.; Koval, M.; Machin, G.

    2015-03-01

    Thermocouples are used in a wide variety of industrial applications in which they play an important role for temperature control and monitoring. Wire inhomogeneity and hysteresis effects are major sources of uncertainty in thermocouple measurements. To efficiently mitigate these effects, it is first necessary to explore the impact of strain-induced inhomogeneities and hysteresis, and their contribution to the uncertainty. This article investigates homogeneity and hysteresis effects in Types N and K mineral-insulated metal-sheathed (MIMS) thermocouples. Homogeneity of thermocouple wires is known to change when mechanical strain is experienced by the thermoelements. To test this influence, bends of increasingly small radii, typical in industrial applications, were made to a number of thermocouples with different sheath diameters. The change in homogeneity was determined through controlled immersion of the thermocouple into an isothermal liquid oil bath at and was found to be very small at for Type K thermocouples, with no measureable change in Type N thermocouples found. An experiment to determine the hysteresis effect in thermocouples was performed on swaged, MIMS Type N and Type K thermocouples, in the temperature range from to . The hysteresis measurements presented simulate the conditions that thermocouples may be exposed to in industrial applications through continuous cycling over 136 h. During this exposure, a characteristic drift from the reference function has been observed but no considerable difference between the heating and cooling measurements was measureable. The measured differences were within the measurement uncertainties; therefore, no hysteresis was observed.

  16. Thermocouples of tantalum and rhenium alloys for more stable vacuum-high temperature performance

    NASA Technical Reports Server (NTRS)

    Morris, J. F. (Inventor)

    1977-01-01

    Thermocouples of the present invention provide stability and performance reliability in systems involving high temperatures and vacuums by employing a bimetallic thermocouple sensor wherein each metal of the sensor is selected from a group of metals comprising tantalum and rhenium and alloys containing only those two metals. The tantalum, rhenium thermocouple sensor alloys provide bare metal thermocouple sensors having advantageous vapor pressure compatibilities and performance characteristics. The compatibility and physical characteristics of the thermocouple sensor alloys of the present invention result in improved emf, temperature properties and thermocouple hot junction performance. The thermocouples formed of the tantalum, rhenium alloys exhibit reliability and performance stability in systems involving high temperatures and vacuums and are adaptable to space propulsion and power systems and nuclear environments.

  17. A joint computational and experimental study to evaluate Inconel-sheathed thermocouple performance in flames.

    SciTech Connect

    Brundage, Aaron L.; Nicolette, Vernon F.; Donaldson, A. Burl; Kearney, Sean Patrick; Gill, Walter

    2005-09-01

    A joint experimental and computational study was performed to evaluate the capability of the Sandia Fire Code VULCAN to predict thermocouple response temperature. Thermocouple temperatures recorded by an Inconel-sheathed thermocouple inserted into a near-adiabatic flat flame were predicted by companion VULCAN simulations. The predicted thermocouple temperatures were within 6% of the measured values, with the error primarily attributable to uncertainty in Inconel 600 emissivity and axial conduction losses along the length of the thermocouple assembly. Hence, it is recommended that future thermocouple models (for Inconel-sheathed designs) include a correction for axial conduction. Given the remarkable agreement between experiment and simulation, it is recommended that the analysis be repeated for thermocouples in flames with pollutants such as soot.

  18. Thin film thermocouples for thermoelectric characterization of nanostructured materials

    NASA Astrophysics Data System (ADS)

    Grayson, Matthew; Zhou, Chuanle; Varrenti, Andrew; Chyung, Seung Hye; Long, Jieyi; Memik, Seda

    2011-03-01

    The increased use of nanostructured materials as thermoelectrics requires reliable and accurate characterization of the anisotropic thermal coefficients of small structures, such as superlattices and quantum wire networks. Thin evaporated metal films can be used to create thermocouples with a very small thermal mass and low thermal conductivity, in order to measure thermal gradients on nanostructures and thereby measure the thermal conductivity and the Seebeck coefficient of the nanostructure. In this work we confirm the known result that thin metal films have lower Seebeck coefficients than bulk metals, and we also calibrate the Seebeck coefficient of a thin-film Ni/Cr thermocouple with 50 nm thickness, showing it to have about 1/4 the bulk value. We demonstrate reproducibility of this thin-filmSeebeck coefficient on multiple substrates, and we show that this coefficient does, in fact, change as a function of film thickness. We will discuss prototype measurement designs and preliminary work as to how these thin films can be used to study both Seebeck coefficients and thermal conductivities of superlattices in various geometries. The same technology can in principle be used on integrated circuits for thermal mapping, under the name ``Integrated On-Chip Thermocouple Array'' (IOTA).

  19. Leg lengthening and shortening

    MedlinePlus

    ... lead to very unequal leg lengths. They include: Poliomyelitis Cerebral palsy Small, weak muscles or short, tight ( ... Cerebral palsy Legg-Calve-Perthes disease Long bones Polio Review Date 11/20/2014 Updated by: Neil ...

  20. Peripheral artery bypass - leg

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/007394.htm Peripheral artery bypass - leg To use the sharing features on this page, please enable JavaScript. Peripheral artery bypass is surgery to reroute the blood supply ...

  1. Restless Legs Syndrome

    MedlinePlus

    ... due to an imbalance of the brain chemical dopamine, which sends messages to control muscle movement. Heredity ... in your legs. These include: Medications that increase dopamine in the brain. These medications reduce motion in ...

  2. Night Leg Cramps

    MedlinePlus

    ... feet or thighs might cramp as well. Forcefully stretching the contracted muscle relieves the pain. Most of ... include: Drinking plenty of fluids to avoid dehydration Stretching your leg muscles or riding a stationary bicycle ...

  3. Enhancements to High Temperature In-Pile Thermocouple Performance

    SciTech Connect

    J. C. Crepeau; J. L. Rempe; J. E. Daw; D. L. Knudson; K. G. Condie; S. C. Wilkins

    2008-03-01

    A joint University of Idaho (UI) and Idaho National Laboratory (INL) University Nuclear Research Initiative (UNERI) was to initiated to extend initial INL efforts to develop doped lybdenum/niobium alloy High Temperature Irradiation Resistant Thermocouples (HTIR-TCs). The overall objective of this UNERI was to develop recommendations for an optimized thermocouple design for high temperature, long duration, in-pile testing by expanding upon results from initial INL efforts. Tasks to quantify the impact of candidate enhancements, such as alternate alloys, alternate geometries, and alternate thermocouple fabrication techniques, on thermocouple performance were completed at INL's High Temperature Test Laboratory (HTTL), a state of the art facility equipped with specialized equipment and trained staff in the area of high temperature instrumentation development and evaluation. Key results of these evaluations, which are documented in this report, are as follows. The doped molybdenum and Nb-1%Zr, which were proposed in the initial INL HTIR-TC design, were found to retain ductility better than the developmental molybdenum-low niobium alloys and the niobium-low molybdenum alloys evaluated. Hence, the performance and lower cost of the commercially available KW-Mo makes a thermocouple containing KW-Mo and Nb-1%Zr the best option at this time. HTIR-TCs containing larger diameter wires offer the potential to increase HTIR-TC stability and reliability at higher temperatures. HTIR-TC heat treatment temperatures and times should be limited to not more than 100 °C above the proposed operating temperatures and to durations of at least 4 to 5 hours. Preliminary investigations suggest that the performance of swaged and loose assembly HTIR-TC designs is similar. However, the swaged designs are less expensive and easier to construct. In addition to optimizing HTIR-TC performance, This UNERI project provided unique opportunities to several University of Idaho students, allowing them to

  4. Enhancements to High Temperature In-Pile Thermocouple Performance

    SciTech Connect

    J.C. Crepeau; J.L. Rempe; J.E. Daw; D.L. Knudson: K.G. Condie; S.C. Wilkins

    2008-03-31

    A joint University of Idaho (UI) and Idaho National Laboratory (INL) University Nuclear Research Initiative (UNERI) was to initiated to extend initial INL efforts to develop doped molybdenum/niobium alloy High Temperature Irradiation Resistant Thermocouples (HTIR-TCs). The overall objective of this UNERI was to develop recommendations for an optimized thermocouple design for high temperature, long duration, in-pile testing by expanding upon results from initial INL efforts. Tasks to quantify the impact of candidate enhancements, such as alternate alloys, alternate geometries, and alternate thermocouple fabrication techniques, on thermocouple performance were completed at INL's High Temperature Test Laboratory (HTTL), a state of the art facility equipped with specialized equipment and trained staff in the area of high temperature instrumentation development and evaluation. Key results of these evaluations, which are documented in this report, are as follows. The doped molybdenum and Nb-1%Zr, which were proposed in the initial INL HTIR-TC design, were found to retain ductility better than the developmental molybdenum-low niobium alloys and the niobium-low molybdenum alloys evaluated. Hence, the performance and lower cost of the commercially available KW-Mo makes a thermocouple containing KW-Mo and Nb-1%Zr the best option at this time. HTIR-TCs containing larger diameter wires offer the potential to increase HTIR-TC stability and reliability at higher temperatures. HTIR-TC heat treatment temperatures and times should be limited to not more than 100 C above the proposed operating temperatures and to durations of at least 4 to 5 hours. Preliminary investigations suggest that the performance of swaged and loose assembly HTIR-TC designs is similar. However, the swaged designs are less expensive and easier to construct. In addition to optimizing HTIR-TC performance, This UNERI project provided unique opportunities to several University of Idaho students, allowing them to

  5. Cold Stress

    MedlinePlus

    ... Publications and Products Programs Contact NIOSH NIOSH COLD STRESS Recommend on Facebook Tweet Share Compartir Workers who ... cold environments may be at risk of cold stress. Extreme cold weather is a dangerous situation that ...

  6. Characterization of a Method for Inverse Heat Conduction Using Real and Simulated Thermocouple Data

    NASA Technical Reports Server (NTRS)

    Pizzo, Michelle E.; Glass, David E.

    2017-01-01

    It is often impractical to instrument the external surface of high-speed vehicles due to the aerothermodynamic heating. Temperatures can instead be measured internal to the structure using embedded thermocouples, and direct and inverse methods can then be used to estimate temperature and heat flux on the external surface. Two thermocouples embedded at different depths are required to solve direct and inverse problems, and filtering schemes are used to reduce noise in the measured data. Accuracy in the estimated surface temperature and heat flux is dependent on several factors. Factors include the thermocouple location through the thickness of a material, the sensitivity of the surface solution to the error in the specified location of the embedded thermocouples, and the sensitivity to the error in thermocouple data. The effect of these factors on solution accuracy is studied using the methodology discussed in the work of Pizzo, et. al.1 A numerical study is performed to determine if there is an optimal depth at which to embed one thermocouple through the thickness of a material assuming that a second thermocouple is installed on the back face. Solution accuracy will be discussed for a range of embedded thermocouple depths. Moreover, the sensitivity of the surface solution to (a) the error in the specified location of the embedded thermocouple and to (b) the error in the thermocouple data are quantified using numerical simulation, and the results are discussed.

  7. Actuator device for artificial leg

    NASA Technical Reports Server (NTRS)

    Burch, J. L. (Inventor)

    1976-01-01

    An actuator device is described for moving an artificial leg of a person having a prosthesis replacing an entire leg and hip joint. The device includes a first articulated hip joint assembly carried by the natural leg and a second articulated hip joint assembly carried by the prosthesis whereby energy from the movement of the natural leg is transferred by a compressible fluid from the first hip joint assembly to the second hip joint assembly for moving the artificial leg.

  8. Venous leg ulcers

    PubMed Central

    2011-01-01

    Introduction Leg ulcers usually occur secondary to venous reflux or obstruction, but 20% of people with leg ulcers have arterial disease, with or without venous disorders. Between 1.5 and 3.0/1000 people have active leg ulcers. Prevalence increases with age to about 20/1000 in people aged over 80 years. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of standard treatments, adjuvant treatments, and organisational interventions for venous leg ulcers? What are the effects of advice about self-help interventions in people receiving usual care for venous leg ulcers? What are the effects of interventions to prevent recurrence of venous leg ulcers? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2011 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 101 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: compression bandages and stockings, cultured allogenic (single or bilayer) skin replacement, debriding agents, dressings (cellulose, collagen, film, foam, hyaluronic acid-derived, semi-occlusive alginate), hydrocolloid (occlusive) dressings in the presence of compression, intermittent pneumatic compression, intravenous prostaglandin E1, larval therapy, laser treatment (low-level), leg ulcer clinics, multilayer elastic system, multilayer elastomeric (or non-elastomeric) high-compression regimens or bandages, oral treatments (aspirin, flavonoids

  9. Athletes' leg pains.

    PubMed Central

    Orava, S.; Puranen, J.

    1979-01-01

    The frequency and nature of exertion pains of the leg in athletes were studied in 2,750 cases of overuse injuries treated at the Sports Clinic of the Deaconess Institute of Oulu, Finland, during the years 1972-1977. 465 cases of exertion pain (18%) were located in the shin. The medial tibial syndrome was the most common overuse injury among these athletes, comprising 9.5% of all exertion injuries and 60% of the leg exertion pains. Together with stress fracture of the tibia, the second most common exertion pain of the leg, it accounted for 75% of the total leg pains. There are certain difficulties in differentiating between the medial tibial syndrome and stress fracture of the tibia. They both occur at the same site with similar symptoms. Radiological examination and isotope scanning are needed. The medial tibial syndrome is an overuse injury at the medial tibial border caused by running exercises. The pain is elicited by exertional ischaemia. The pathogenesis is explained by increased pressure in the fascial compartment of the deep flexor muscles due to prolonged exercise. Similar chronic ischaemic pains from exercise are also found in other fascial compartments of the leg, especially in the anterior compartment. The only treatment needed for stress fractures is rest from training. Fascial compartment pains also usually subside. If chronic fascial syndromes prevent training, fasciotomy is recommended as a reliable method to restore the athlete to normal training without pains. PMID:486888

  10. Summary of Thermocouple Performance During Advanced Gas Reactor Fuel Irradiation Experiments in the Advanced Test Reactor and Out-of-Pile Thermocouple Testing in Support of Such Experiments

    SciTech Connect

    A. J. Palmer; DC Haggard; J. W. Herter; M. Scervini; W. D. Swank; D. L. Knudson; R. S. Cherry

    2011-07-01

    High temperature gas reactor experiments create unique challenges for thermocouple based temperature measurements. As a result of the interaction with neutrons, the thermoelements of the thermocouples undergo transmutation, which produces a time dependent change in composition and, as a consequence, a time dependent drift of the thermocouple signal. This drift is particularly severe for high temperature platinum-rhodium thermocouples (Types S, R, and B); and tungsten-rhenium thermocouples (Types C and W). For lower temperature applications, previous experiences with type K thermocouples in nuclear reactors have shown that they are affected by neutron irradiation only to a limited extent. Similarly type N thermocouples are expected to be only slightly affected by neutron fluxes. Currently the use of these Nickel based thermocouples is limited when the temperature exceeds 1000°C due to drift related to phenomena other than nuclear irradiation. High rates of open-circuit failure are also typical. Over the past ten years, three long-term Advanced Gas Reactor (AGR) experiments have been conducted with measured temperatures ranging from 700oC – 1200oC. A variety of standard Type N and specialty thermocouple designs have been used in these experiments with mixed results. A brief summary of thermocouple performance in these experiments is provided. Most recently, out of pile testing has been conducted on a variety of Type N thermocouple designs at the following (nominal) temperatures and durations: 1150oC and 1200oC for 2000 hours at each temperature, followed by 200 hours at 1250oC, and 200 hours at 1300oC. The standard Type N design utilizes high purity crushed MgO insulation and an Inconel 600 sheath. Several variations on the standard Type N design were tested, including Haynes 214 alloy sheath, spinel (MgAl2O4) insulation instead of MgO, a customized sheath developed at the University of Cambridge, and finally a loose assembly thermocouple with hard fired alumina

  11. Summary of thermocouple performance during advanced gas reactor fuel irradiation experiments in the advanced test reactor and out-of-pile thermocouple testing in support of such experiments

    SciTech Connect

    Palmer, A. J.; Haggard, DC; Herter, J. W.; Swank, W. D.; Knudson, D. L.; Cherry, R. S.; Scervini, M.

    2015-07-01

    High temperature gas reactor experiments create unique challenges for thermocouple-based temperature measurements. As a result of the interaction with neutrons, the thermoelements of the thermocouples undergo transmutation, which produces a time-dependent change in composition and, as a consequence, a time-dependent drift of the thermocouple signal. This drift is particularly severe for high temperature platinum-rhodium thermocouples (Types S, R, and B) and tungsten-rhenium thermocouples (Type C). For lower temperature applications, previous experiences with Type K thermocouples in nuclear reactors have shown that they are affected by neutron irradiation only to a limited extent. Similarly, Type N thermocouples are expected to be only slightly affected by neutron fluence. Currently, the use of these nickel-based thermocouples is limited when the temperature exceeds 1000 deg. C due to drift related to phenomena other than nuclear irradiation. High rates of open-circuit failure are also typical. Over the past 10 years, three long-term Advanced Gas Reactor experiments have been conducted with measured temperatures ranging from 700 deg. C - 1200 deg. C. A variety of standard Type N and specialty thermocouple designs have been used in these experiments with mixed results. A brief summary of thermocouple performance in these experiments is provided. Most recently, out-of-pile testing has been conducted on a variety of Type N thermocouple designs at the following (nominal) temperatures and durations: 1150 deg. C and 1200 deg. C for 2,000 hours at each temperature, followed by 200 hours at 1250 deg. C and 200 hours at 1300 deg. C. The standard Type N design utilizes high purity, crushed MgO insulation and an Inconel 600 sheath. Several variations on the standard Type N design were tested, including a Haynes 214 alloy sheath, spinel (MgAl{sub 2}O{sub 4}) insulation instead of MgO, a customized sheath developed at the University of Cambridge, and finally a loose assembly

  12. Temporary Thermocouple Attachment for Thermal/Vacuum Testing at Non-Extreme Temperatures

    NASA Technical Reports Server (NTRS)

    Ungar, Eugene K.; Wright, Sarah E.

    2016-01-01

    Post-test examination and data analysis that followed a two week long vacuum test showed that numerous self-stick thermocouples became detached from the test article. The thermocouples were reattached with thermally conductive epoxy and the test was repeated to obtain the required data. Because the thermocouple detachment resulted in significant expense and rework, it was decided to investigate the temporary attachment methods used around NASA and to perform a test to assess their efficacy. The present work describes the original test and the analysis that showed that the thermocouples had become detached, temporary thermocouple attachment methods assessed in the retest and in the thermocouple attachment test, and makes a recommendation for attachment methods for future tests.

  13. Correction of thermal gradient errors in stem thermocouple hygrometers.

    PubMed

    Michel, B E

    1979-01-01

    Stem thermocouple hygrometers were subjected to transient and stable thermal gradients while in contact with reference solutions of NaCl. Both dew point and psychrometric voltages were directly related to zero offset voltages, the latter reflecting the size of the thermal gradient. Although slopes were affected by absolute temperature, they were not affected by water potential. One hygrometer required a correction of 1.75 bars water potential per microvolt of zero offset, a value that was constant from 20 to 30 C.

  14. Recent improvements on micro-thermocouple based SThM

    NASA Astrophysics Data System (ADS)

    Nguyen, TP; Thiery, L.; Teyssieux, D.; Briand, D.; Vairac, P.

    2017-01-01

    The scanning thermal microscope (SThM) has become a versatile tool for local surface temperature mapping or measuring thermal properties of solid materials. In this article, we present recent improvements in a SThM system, based on a micro-wire thermocouple probe associated with a quartz tuning fork for contact strength detection. Some results obtained on an electrothermal micro-hotplate device, operated in active and passive modes, allow demonstrating its performance as a coupled force detection and thermal measurement system.

  15. Thin-Film Thermocouple Technology Demonstrated for Reliable Heat Transfer Measurements

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Exploratory work is in progress to apply thin-film thermocouples to localized heat transfer measurements on turbine engine vanes and blades. The emerging thin-film thermocouple technology shows great potential to improve the accuracy of local heat transfer measurements. To verify and master the experimental methodology of thin-film thermocouples, the NASA Lewis Research Center conducted a proof-of-concept experiment in a controlled environment before applying the thin-film sensors to turbine tests.

  16. Hemoglobinopathies and Leg Ulcers.

    PubMed

    Alavi, Afsaneh; Kirsner, Robert S

    2015-09-01

    Major hemoglobinopathies, including sickle cell anemia, are becoming a global health issue. Leg ulcers are the most common cutaneous manifestation of sickle cell disease and an important contributor to morbidity burden in this population. Leg ulcers following sickling disorders are extremely painful, and hard to heal. The clinical evidence for the optimal management of these ulcers is limited. Treating the cause and the strategies to prevent sickling are the mainstay of treatment. The basic principles of wound bed preparation and compression therapy is beneficial in these patients.

  17. Pt/Pd thermocouple resilience over 327 operating hours in an industrial calibration laboratory

    NASA Astrophysics Data System (ADS)

    Elliott, C. J.; Pearce, J. V.; Machin, G.; Ford, T.; Hicks, K.

    2013-09-01

    Two Pt/Pd thermocouples have been manufactured industrially at CCPI-Europe to a robust design optimised by NPL. The first has been exposed to temperatures up to 1000 °C for 93 operating hours and the second exposed to higher temperatures (up to 1300 °C) for 327 operating hours, over the course of a year. No significant drift is observed in the temperature measurement for either Pt/Pd thermocouple, when compared against reference Type R thermocouples. This work demonstrates the long-term stability and reliability of Pt/Pd thermocouples in use within an industrial calibration environment with this optimised, robust design.

  18. Operation and Service Manual for Thermocouple Checkout Box 52E440047,

    DTIC Science & Technology

    for testing spacecraft thermocouples and their associated wiring harnesses . The STDR describes the unit, its controls and their function and contains servicing instructions for preventive maintenance. (Author)

  19. 20. DETAIL, TYPICAL LEG CONNECTION, CROSS BRACING AT LEG, WITH ...

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

    20. DETAIL, TYPICAL LEG CONNECTION, CROSS BRACING AT LEG, WITH CROSSED BRACE BLOCK, GROUND WIRES AND GUIDE WIRE. - Hat Point Fire Lookout Tower, Forest Service Road #4340, 24 miles from Imnaha, Imnaha, Wallowa County, OR

  20. High Temperature Irradiation-Resistant Thermocouple Performance Improvements

    SciTech Connect

    Joshua Daw; Joy Rempe; Darrell Knudson; John Crepeau; S. Curtis Wilkins

    2009-04-01

    Traditional methods for measuring temperature in-pile degrade at temperatures above 1100 ºC. To address this instrumentation need, the Idaho National Laboratory (INL) developed and evaluated the performance of a high temperature irradiation-resistant thermocouple (HTIR-TC) that contains alloys of molybdenum and niobium. Data from high temperature (up to 1500 ºC) long duration (up to 4000 hours) tests and on-going irradiations at INL’s Advanced Test Reactor demonstrate the superiority of these sensors to commercially-available thermocouples. However, several options have been identified that could further enhance their reliability, reduce their production costs, and allow their use in a wider range of operating conditions. This paper presents results from on-going Idaho National Laboratory (INL)/University of Idaho (UI) efforts to investigate options to improve HTIR-TC ductility, reliability, and resolution by investigating specially-formulated alloys of molybdenum and niobium and alternate diameter thermoelements (wires). In addition, on-going efforts to evaluate alternate fabrication approaches, such as drawn and loose assembly techniques will be discussed. Efforts to reduce HTIR-TC fabrication costs, such as the use of less expensive extension cable will also be presented. Finally, customized HTIR-TC designs developed for specific customer needs will be summarized to emphasize the varied conditions under which these sensors may be used.

  1. Heat flux measurements on ceramics with thin film thermocouples

    NASA Technical Reports Server (NTRS)

    Holanda, Raymond; Anderson, Robert C.; Liebert, Curt H.

    1993-01-01

    Two methods were devised to measure heat flux through a thick ceramic using thin film thermocouples. The thermocouples were deposited on the front and back face of a flat ceramic substrate. The heat flux was applied to the front surface of the ceramic using an arc lamp Heat Flux Calibration Facility. Silicon nitride and mullite ceramics were used; two thicknesses of each material was tested, with ceramic temperatures to 1500 C. Heat flux ranged from 0.05-2.5 MW/m2(sup 2). One method for heat flux determination used an approximation technique to calculate instantaneous values of heat flux vs time; the other method used an extrapolation technique to determine the steady state heat flux from a record of transient data. Neither method measures heat flux in real time but the techniques may easily be adapted for quasi-real time measurement. In cases where a significant portion of the transient heat flux data is available, the calculated transient heat flux is seen to approach the extrapolated steady state heat flux value as expected.

  2. An Accurate Temperature Correction Model for Thermocouple Hygrometers 1

    PubMed Central

    Savage, Michael J.; Cass, Alfred; de Jager, James M.

    1982-01-01

    Numerous water relation studies have used thermocouple hygrometers routinely. However, the accurate temperature correction of hygrometer calibration curve slopes seems to have been largely neglected in both psychrometric and dewpoint techniques. In the case of thermocouple psychrometers, two temperature correction models are proposed, each based on measurement of the thermojunction radius and calculation of the theoretical voltage sensitivity to changes in water potential. The first model relies on calibration at a single temperature and the second at two temperatures. Both these models were more accurate than the temperature correction models currently in use for four psychrometers calibrated over a range of temperatures (15-38°C). The model based on calibration at two temperatures is superior to that based on only one calibration. The model proposed for dewpoint hygrometers is similar to that for psychrometers. It is based on the theoretical voltage sensitivity to changes in water potential. Comparison with empirical data from three dewpoint hygrometers calibrated at four different temperatures indicates that these instruments need only be calibrated at, e.g. 25°C, if the calibration slopes are corrected for temperature. PMID:16662241

  3. An accurate temperature correction model for thermocouple hygrometers.

    PubMed

    Savage, M J; Cass, A; de Jager, J M

    1982-02-01

    Numerous water relation studies have used thermocouple hygrometers routinely. However, the accurate temperature correction of hygrometer calibration curve slopes seems to have been largely neglected in both psychrometric and dewpoint techniques.In the case of thermocouple psychrometers, two temperature correction models are proposed, each based on measurement of the thermojunction radius and calculation of the theoretical voltage sensitivity to changes in water potential. The first model relies on calibration at a single temperature and the second at two temperatures. Both these models were more accurate than the temperature correction models currently in use for four psychrometers calibrated over a range of temperatures (15-38 degrees C). The model based on calibration at two temperatures is superior to that based on only one calibration.The model proposed for dewpoint hygrometers is similar to that for psychrometers. It is based on the theoretical voltage sensitivity to changes in water potential. Comparison with empirical data from three dewpoint hygrometers calibrated at four different temperatures indicates that these instruments need only be calibrated at, e.g. 25 degrees C, if the calibration slopes are corrected for temperature.

  4. Dynamically Stable Legged Locomotion

    DTIC Science & Technology

    1983-12-13

    to bound. 3.2 Introduction Animals, including man, demonstrate feats of great mobility. Their legs allow them to move swiftly over terrain that is...135 Witt.D.C. A feasibility study on automatically-controlled powered lower-limb prosthesis . University of Oxford.. Department of Engineering Science

  5. Leg lengthening - slideshow

    MedlinePlus

    ... Indications URL of this page: //medlineplus.gov/ency/presentations/100127.htm Leg lengthening - series—Indications To use the sharing features on this page, please enable JavaScript. Go to slide 1 out of 3 Go to slide 2 ...

  6. Foot, leg, and ankle swelling

    MedlinePlus

    ... feet - legs; Ankle swelling; Foot swelling; Leg swelling; Edema - peripheral; Peripheral edema ... 51. Trayes KP, Studdiford JS, Pickle S, Tully AS. Edema: Diagnosis and management. Am Fam Phys . 2013;88( ...

  7. Effective leg stiffness in running.

    PubMed

    Blum, Yvonne; Lipfert, Susanne W; Seyfarth, Andre

    2009-10-16

    Leg stiffness is a common parameter used to characterize leg function during bouncing gaits, like running and hopping. In the literature, different methods to approximate leg stiffness based on kinetic and kinematic parameters are described. A challenging point in estimating leg stiffness is the definition of leg compression during contact. In this paper four methods (methods A-D) based on ground reaction forces (GRF) and one method (method E) relying on temporal parameters are described. Leg stiffness calculated by these five methods is compared with running patterns, predicted by the spring mass model. The best and simplest approximation of leg stiffness is method E. It requires only easily accessible parameters (contact time, flight time, resting leg length, body mass and the leg's touch down angle). Method D is of similar quality but additionally requires the time-dependent progression of the GRF. The other three methods show clear differences from the model predictions by over- or underestimating leg stiffness, especially at slow speeds. Leg stiffness is derived from a conceptual model of legged locomotion and does not exist without this model. Therefore, it is important to prove which experimental method is suited best for approximating the stiffness in a specific task. This will help to interpret the predictions of the conceptual model in comparison with experimental data.

  8. Common Cold

    MedlinePlus

    ... nose, coughing - everyone knows the symptoms of the common cold. It is probably the most common illness. In ... avoid colds. There is no cure for the common cold. For relief, try Getting plenty of rest Drinking ...

  9. Development of a Sheathed Miniature Aerothermal Reentry Thermocouple for Thermal Protection System Materials

    NASA Technical Reports Server (NTRS)

    Martinez, Edward R.; Weber, Carissa Tudryn; Oishi, Tomo; Santos, Jose; Mach, Joseph

    2011-01-01

    The Sheathed Miniature Aerothermal Reentry Thermocouple is a micro-miniature thermocouple for high temperature measurement in extreme environments. It is available for use in Thermal Protection System materials for ground testing and flight. This paper discusses the heritage, and design of the instrument. Experimental and analytical methods used to verify its performance and limitations are described.

  10. Development of Thin Film Thermocouples on Ceramic Materials for Advanced Propulsion System Applications

    NASA Technical Reports Server (NTRS)

    Holanda, R.

    1992-01-01

    Thin film thermocouples have been developed for use on metal parts in jet engines to 1000 c. However, advanced propulsion systems are being developed that will use ceramic materials and reach higher temperatures. The purpose of this work is to develop thin film thermocouples for use on ceramic materials. The new thin film thermocouples are Pt13Rh/Pt fabricated by the sputtering process. Lead wires are attached using the parallel-gap welding process. The ceramic materials tested are silicon nitride, silicon carbide, aluminum oxide, and mullite. Both steady state and thermal cycling furnace tests were performed in the temperature range to 1500 C. High-heating-rate tests were performed in an arc lamp heat-flux-calibration facility. The fabrication of the thin film thermocouples is described. The thin film thermocouple output was compared to a reference wire thermocouple. Drift of the thin film thermocouples was determined, and causes of drift are discussed. The results of high heating rate tests up to 2500 C/sec are presented. The stability of the ceramic materials is examined. It is concluded that Pt13Rh/Pt thin film thermocouples are capable of meeting lifetime goals of 50 hours or more up to temperature of 1500 C depending on the stability of the particular ceramic substrate.

  11. Development of thin film thermocouples on ceramic materials for advanced propulsion system applications

    NASA Technical Reports Server (NTRS)

    Holanda, Raymond

    1993-01-01

    Thin film thermocouples were developed for use on metal parts in jet engines to 1000 C. However, advanced propulsion systems are being developed that will use ceramic materials and reach higher temperatures. The purpose is to develop thin film thermocouples for use on ceramic materials. The new thin film thermocouples are Pt13Rh/Pt fabricated by the sputtering process. Lead wires are attached using the parallel-gap welding process. The ceramic materials tested are silicon nitride, silicon carbide, aluminum oxide, and mullite. Both steady state and thermal cycling furnace tests were performed in the temperature range to 1500 C. High-heating-rate tests were performed in an arc lamp heat-flux-calibration facility. The fabrication of the thin film thermocouples is described. The thin film thermocouple output was compared to a reference wire thermocouple. Drift of the thin film thermocouples was determined, and causes of drift are discussed. The results of high heating rate tests up to 2500 C/sec are presented. The stability of the ceramic materials is examined. It is concluded that Pt13Rh/Pt thin film thermocouples are capable of meeting lifetime goals of 50 hr or more up to temperatures of 1500 C depending on the stability of the particular ceramic substrate.

  12. High-Temperature, Thin-Film Ceramic Thermocouples Developed

    NASA Technical Reports Server (NTRS)

    Sayir, Ali; Blaha, Charles A.; Gonzalez, Jose M.

    2005-01-01

    To enable long-duration, more distant human and robotic missions for the Vision for Space Exploration, as well as safer, lighter, quieter, and more fuel efficient vehicles for aeronautics and space transportation, NASA is developing instrumentation and material technologies. The high-temperature capabilities of thin-film ceramic thermocouples are being explored at the NASA Glenn Research Center by the Sensors and Electronics Branch and the Ceramics Branch in partnership with Case Western Reserve University (CWRU). Glenn s Sensors and Electronics Branch is developing thin-film sensors for surface measurement of strain, temperature, heat flux, and surface flow in propulsion system research. Glenn s Ceramics Branch, in conjunction with CWRU, is developing structural and functional ceramic technology for aeropropulsion and space propulsion.

  13. Thermoelectric effect in very thin film Pt/Au thermocouples

    SciTech Connect

    Salvadori, M.C.; Vaz, A.R.; Teixeira, F.S.; Cattani, M.; Brown,I.G.

    2006-01-10

    The thickness dependence of the thermoelectric power of Pt films of variable thickness on a reference Au film has been determined for the case when the Pt film thickness, t, is not large compared to the charge carrier mean free path, {ell}, that is, t/{ell}. Pt film thicknesses down to 2.2 nm were investigated. We find that {Delta}S{sub F} = S{sub B}-S{sub F} (where S{sub B} and S{sub F} are the thermopowers of the Pt bulk and film, respectively) does not vary linearly as 1/t as is the case for thin film thermocouples when the film thickness is large compared to the charge carrier mean free path.

  14. Measurement of frequency response in short thermocouple wires

    NASA Technical Reports Server (NTRS)

    Forney, L. J.; Meeks, E. L.; Ma, J.

    1991-01-01

    Experimental measurements are made for the steady-state frequency response of a supported thermocouple wire. In particular, the effects of axial heat conduction are demonstrated for both a supported one material wire (type K) and a two material wire (type T) with unequal material properties across the junction. The data for the amplitude ratio and phase angle are correlated to within 10 percent with the theoretical predictions of Fralick and Forney (1991). This is accomplished by choosing a natural frequency omega(sub n) for the wire data to correlate the first order response at large gas temperature frequencies. It is found that a large bead size, however, will increase the amplitude ratio at low frequencies but decreas the natural frequency of the wire. The phase angle data are also distorted for imperfect junctions.

  15. Reference data for thermocouple materials below the ice point.

    NASA Technical Reports Server (NTRS)

    Sparks, L. L.; Powell, R. L.

    1972-01-01

    Standard thermoelectric data have been determined for four thermocouple combinations used below the ice point: commercial types E, K, and T and the special combination of KP vs Au-0.07 at.% Fe. Power series coefficients necessary to generate E = f(T) data for these combinations are given. In addition, extensive tests were carried out to ascertain the variability between materials from different manufacturers. Typical wires processed for low-temperature usage often have slightly thermoelectric properties (up to 1%) from those, nominally identical, wires made for high-temperature applications. Generally, type E is the most satisfactory standardized commercial combination. The Au-0.07 at.% Fe material has been examined in particular detail, because it is not yet an ISA standard material. It has excellent sensitivity in the liquid helium/liquid hydrogen temperature range and a nearly linear thermovoltage at higher temperatures.

  16. ORTHOPEDIC LEG BRACE

    NASA Technical Reports Server (NTRS)

    Myers, William Neil (Inventor)

    2005-01-01

    Knee braces generally have been rigid in both the knee bending direction and in the knee straightening direction unless a manually operated release is incorporated in them to allow the knee to bend. Desirably a braced knee joint should effectively duplicate the compound, complex, actions of a normal knee. The key to knee braces is the knee joint housing. The housing herein carries a number of cam action pawls. with teeth adapted to engage the internal teeth of a ratchet ring mounted in the housing. Cam action return springs and the shape of the cam action pawl teeth allow rotation of the ratchet ring in a leg straightening direction while still supporting a load. The leg can then be extended during walking while at the same time being prevented by the cam action pawls from buckling in the knee bending direction.

  17. Development of Local Gas Temperature Measurement Technique inside a Combustion Chamber Using Two-Wire Thermocouple

    NASA Astrophysics Data System (ADS)

    Kobayashi, Shigemi; Moriyoshi, Yasuo; Enomoto, Yoshiteru

    Thermocouples are widely used to measure the local gas temperature due to its accuracy and convenience. However, it is difficult to use thermocouples in a transient phenomenon such as reacting fields. In this study, the unsteady gas temperature inside a combustion chamber was measured by using an improved two-wire thermocouple technique. Based on previous two-wire methods, some modifications were examined. Firstly, numerical analysis of heat transfer between transient flow and thermocouple was performed to see what kind of modification was required. Secondly, a correction term was added to the basic equation, which was validated by experiments using a Rapid Compression and Expansion Machine. Finally, an improved two-wire thermocouple technique was evaluated by measuring the transient gas temperature inside a combustion chamber and compared to the estimated temperature using measured pressure data and assumptions of chemical equilibrium.

  18. Investigation of factors affecting the heater wire method of calibrating fine wire thermocouples

    NASA Technical Reports Server (NTRS)

    Keshock, E. G.

    1972-01-01

    An analytical investigation was made of a transient method of calibrating fine wire thermocouples. The system consisted of a 10 mil diameter standard thermocouple (Pt, Pt-13% Rh) and an 0.8 mil diameter chromel-alumel thermocouple attached to a 20 mil diameter electrically heated platinum wire. The calibration procedure consisted of electrically heating the wire to approximately 2500 F within about a seven-second period in an environment approximating atmospheric conditions at 120,000 feet. Rapid periodic readout of the standard and fine wire thermocouple signals permitted a comparison of the two temperature indications. An analysis was performed which indicated that the temperature distortion at the heater wire produced by the thermocouple junctions appears to be of negligible magnitude. Consequently, the calibration technique appears to be basically sound, although several practical changes which appear desirable are presented and discussed. Additional investigation is warranted to evaluate radiation effects and transient response characteristics.

  19. Method of preventing leakage of a fluid along and through an insulating jacket of a thermocouple

    DOEpatents

    Thermos, Anthony Constantine; Rahal, Fadi Elias

    2002-01-01

    A thermocouple assembly includes a thermocouple; a plurality of lead wires extending from the thermocouple; an insulating jacket extending along and enclosing the plurality of leads; and at least one internally sealed area within the insulating jacket to prevent fluid leakage along and within the insulating jacket. The invention also provides a method of preventing leakage of a fluid along and through an insulating jacket of a thermocouple including the steps of a) attaching a plurality of lead wires to a thermocouple; b) adding a heat sensitive pseudo-wire to extend along the plurality of lead wires; c) enclosing the lead wires and pseudo-wire inside an insulating jacket; d) locally heating axially spaced portions of the insulating jacket to a temperature which melts the pseudo-wire and fuses it with an interior surface of the jacket.

  20. Thermocouples fabricated on trench sidewall in microfluidic channel bonded with film cover

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Takahiro; Shibata, Masahiro; Kumagai, Shinya; Sasaki, Minoru

    2015-03-01

    Thermocouples on a trench sidewall fronting a flow are fabricated by three-dimensional (3D) photolithography. The conventional thermocouples on the wafer top surface are also fabricated. The performances of these devices are compared. Without the flow inside the microchannel, the thermocouple on the trench sidewall shows the same output voltage as that on the wafer top surface positioned 40 µm from the channel. As a static response, when the microchannel is heated and room-temperature air flows inside the channel, the thermocouple on the sidewall shows a lower voltage. As a dynamic response, when hot air flows inside the channel and replaces the room-temperature air, the thermocouple on the sidewall shows a faster response, increasing its output voltage, and the local temperature of the flow can be measured more precisely.

  1. Venous Leg Ulcers.

    PubMed

    Vivas, Alejandra; Lev-Tov, Hadar; Kirsner, Robert S

    2016-08-02

    This issue provides a clinical overview of venous leg ulcers, focusing on prevention, diagnosis, treatment, and practice improvement. The content of In the Clinic is drawn from the clinical information and education resources of the American College of Physicians (ACP), including MKSAP (Medical Knowledge and Self-Assessment Program). Annals of Internal Medicine editors develop In the Clinic in collaboration with the ACP's Medical Education and Publishing divisions and with the assistance of additional science writers and physician writers.

  2. Leg size and muscle functions associated with leg compliance

    NASA Technical Reports Server (NTRS)

    Convertino, Victor A.; Doerr, Donald F.; Flores, Jose F.; Hoffler, G. Wyckliffe; Buchanan, Paul

    1988-01-01

    The relationship between the leg compliance and factors related to the size of leg muscle and to physical fitness was investigated in ten healthy subjects. Vascular compliance of the leg, as determined by a mercury strain gauge, was found to be not significantly correlated with any variables associated with physical fitness per se (e.g., peak O2 uptake, calf strength, age, body weight, or body composition. On the other hand, leg compliance correlated with the calf cross-sectional area (CSA) and the calculated calf volume, with the CSA of calf muscle being the most dominant contributing factor (while fat and bone were poor predicators). It is suggested that leg compliance can be lowered by increasing calf muscle mass, thus providing structural support to limit the expansion of leg veins.

  3. 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.

  4. Dynamically Stable Legged Locomotion

    DTIC Science & Technology

    1989-09-01

    Borvansky DISTIBUTIo~ j 3T ENT A Approved for pubtc (eLaz-; Distribution Unkn!r hd MIT Artificial Intelligence Laboratory 90 oU3 2?. 0h22 RLAD INSTRUC.TIONS...DATE Advanced Research P rojects Agency September 1989 1400 Wilson Blvd. 13. NUMfiEROF PAGES Arlington, VA 22209 203 14 MONITORING AGENCY NAME A ...this researchi is to bl)id a founidation of knowledge that can leadl bothi to tile coiistl luctionl of useful legged veldlis and to a better

  5. Investigations of Thermocouple Drift Irregularity Impact on Error of their Inhomogeneity Correction

    NASA Astrophysics Data System (ADS)

    Jun, Su; Kochan, Orest

    2014-02-01

    The article examines: (i) the reasons of error due to thermoelectric inhomogeneity of electrodes of thermocouples acquired during prolonged use; (ii) the neural network method of error correction based on a generalization of verification results in several temperature fields; (iii) the method of investigating the impact of changing the speed of the conversion characteristic drift of thermocouple on error correction; (iv) results of this investigation. It is shown that residual error for type K thermocouples at the 5 % level of significance does not exceed μ±0.46 oС and one at the 10 % level of significance does not exceed ±0.25 °С

  6. Biomechanics of Counterweighted One-Legged Cycling.

    PubMed

    Elmer, Steven J; McDaniel, John; Martin, James C

    2016-02-01

    One-legged cycling has served as a valuable research tool and as a training and rehabilitation modality. Biomechanics of one-legged cycling are unnatural because the individual must actively lift the leg during flexion, which can be difficult to coordinate and cause premature fatigue. We compared ankle, knee, and hip biomechanics between two-legged, one-legged, and counterweighted (11.64 kg) one-legged cycling. Ten cyclists performed two-legged (240 W), one-legged (120 W), and counterweighted one-legged (120 W) cycling (80 rpm). Pedal forces and limb kinematics were recorded to determine work during extension and flexion. During counterweighted one-legged cycling relative ankle dorsiflexion, knee flexion, and hip flexion work were less than one-legged but greater than two-legged cycling (all P < .05). Relative ankle plantar flexion and hip extension work for counterweighted one-legged cycling were greater than one-legged but less than two-legged cycling (all P < .05). Relative knee extension work did not differ across conditions. Counterweighted one-legged cycling reduced but did not eliminate differences in joint flexion and extension actions between one- and two-legged cycling. Even with these differences, counterweighted one-legged cycling seemed to have advantages over one-legged cycling. These results, along with previous work highlighting physiological characteristics and training adaptations to counterweighted one-legged cycling, demonstrate that this exercise is a viable alternative to one-legged cycling.

  7. Field installed brazed thermocouple feedthroughs for high vacuum experiments

    NASA Astrophysics Data System (ADS)

    Anderson, P. M.; Messick, C.

    1983-12-01

    In order to reduce the occurrence of vacuum leaks and to increase the availability of the DIII vacuum vessel for experimental operation, effort was applied to developing a vacuum-tight brazed feedthrough system for sheathed thermocouples, stainless steel sheathed conductor cables and tubes for cooling fluids. This brazed technique is a replacement for elastomer O ring sealed feedthroughs that have proven vulnerable to leaks caused by thermal cycling, etc. To date, about 200 feedthroughs were used. Up to 91 were grouped on a single conflat flange mounted in a bulkhead connector configuration which facilitates installation and removal. Investigation was required to select a suitable braze alloy, flux and installation procedure. Braze alloy selection was challenging since the alloy was required to have: (1) melting temperature in excess of the 250 C (482 F) bakeout temperature; (2) no high vapor pressure elements; (3) good wetting properties when used in air with acceptable flux; and (4) good wettability to 300 series stainless steel and Inconel.

  8. Calibration of thermocouple psychrometers and moisture measurements in porous materials

    NASA Astrophysics Data System (ADS)

    Guz, Łukasz; Sobczuk, Henryk; Połednik, Bernard; Guz, Ewa

    2016-07-01

    The paper presents in situ method of peltier psychrometric sensors calibration which allow to determine water potential. Water potential can be easily recalculated into moisture content of the porous material. In order to obtain correct results of water potential, each probe should be calibrated. NaCl salt solutions with molar concentration of 0.4M, 0.7M, 1.0M and 1.4M, were used for calibration which enabled to obtain osmotic potential in range: -1791 kPa to -6487 kPa. Traditionally, the value of voltage generated on thermocouples during wet-bulb temperature depression is calculated in order to determine the calibration function for psychrometric in situ sensors. In the new method of calibration, the field under psychrometric curve along with peltier cooling current and duration was taken into consideration. During calibration, different cooling currents were applied for each salt solution, i.e. 3, 5, 8 mA respectively, as well as different cooling duration for each current (from 2 to 100 sec with 2 sec step). Afterwards, the shape of each psychrometric curve was thoroughly examined and a value of field under psychrometric curve was computed. Results of experiment indicate that there is a robust correlation between field under psychrometric curve and water potential. Calibrations formulas were designated on the basis of these features.

  9. Thin film thermocouples for high temperature turbine application

    NASA Technical Reports Server (NTRS)

    Martin, Lisa C.

    1991-01-01

    The objective is to develop thin film thermocouples (TFTC) for Space Shuttle Main Engine (SSME) components such as the high pressure fuel turbopump (HPFTP) blades and to test TFTC survivability and durability in the SSME environment. The purpose for developing TFTC's for SSME components is to obtain blade temperatures for computational models developed for fluid mechanics and structures. The TFTC must be able to withstand the presence of high temperature, high pressure hydrogen as well as a severe thermal transient due to a cryogenic to combustion temperature change. The TFTC's will eventually be installed and tested on SSME propulsion system components in the SSME test bed engine. The TFTC's were successfully fabricated on flat coupons of MAR-M 246 (Hf+), which is the superalloy material used for HPFTP turbine blades. The TFTC's fabricated on flat coupons survived thermal shock cycling as well as testing in a heat flux measurement facility which provided a rapid thermal transient. The same fabrication procedure was used to deposit TFTC's on HPFTP first stage rotor blades. Other results from the experiments are presented, and future testing plans are discussed.

  10. Common cold

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/000678.htm Common cold To use the sharing features on this page, please enable JavaScript. The common cold most often causes a runny nose, nasal congestion, ...

  11. Options to Extend the Applicability of High Temperature Irradiation Resistant Thermocouples

    SciTech Connect

    Joy L. Rempe; Darrell L. Knudson; Keith G. Condie; S. Curtis Wilkins; John C. Crepeau; Joshua E. Daw; Patrick J. Green

    2007-09-01

    Several options have been identified that could further enhance the reliability and increase the applicability of recently developed Idaho National Laboratory (INL) High Temperature Irradiation Resistant thermocouples (HTIR-TCs) for in-pile testing, allowing their use in higher temperature applications (up to at least 1700 °C). INL and the University of Idaho (UI) are investigating these options with the ultimate objective of providing recommendations for alternate thermocouple designs that are optimized for various applications. This paper reports the status of INL/UI investigations. Results are reported from tests completed to evaluate the ductility, resolution, transient response, and stability of thermocouples made from specially formulated alloys of molybdenum and niobium. In addition, this paper reports preliminary insights gained by comparing the performance of thermocouples fabricated with various heat treatments and alternate geometries.

  12. Evaluation of miniature single-wire sheathed thermocouples for turbine blade temperature measurement

    NASA Technical Reports Server (NTRS)

    Hollanda, R.

    1979-01-01

    Chromel Alumel thermocouples were used, with sheath diameters of 0.15 and 0.25 mm. Tests were conducted at temperatures ranging from 750 to 1250 K. Both steady state and thermal cycling tests were performed for times up to 200 hours. Initial testing was performed in a low velocity gas stream for long time periods using a Meker-type burner. Additional testing was done in a high velocity gas stream for short time periods using a hot gas tunnel and also in a J75 jet engine. A total of eleven 0.15 mm diameter thermocouples and six 0.25 mm diameter thermocouples were tested. Drift rates up to 2.5% in 10 hours were observed. Photomicrographs show that this design is near the limit of miniaturization based on present manufacturing capabilities. Results indicate that the effects of miniaturization on reliability and accuracy must be considered when choosing thermocouples for a particular application.

  13. Design and Operation of a Fast, Thin-Film Thermocouple Probe on a Turbine Engine

    NASA Technical Reports Server (NTRS)

    Meredith, Roger D.; Wrbanek, John D.; Fralick, Gustave C.; Greer, Lawrence C., III; Hunter, Gary W.; Chen, Liang-Yu

    2014-01-01

    As a demonstration of technology maturation, a thin-film temperature sensor probe was fabricated and installed on a F117 turbofan engine via a borescope access port to monitor the temperature experienced in the bleed air passage of the compressor area during an engine checkout test run. To withstand the harsh conditions experienced in this environment, the sensor probe was built from high temperature materials. The thin-film thermocouple sensing elements were deposited by physical vapor deposition using pure metal elements, thus avoiding the inconsistencies of sputter-depositing particular percentages of materials to form standardized alloys commonly found in thermocouples. The sensor probe and assembly were subjected to a strict protocol of multi-axis vibrational testing as well as elevated temperature pressure testing to be qualified for this application. The thin-film thermocouple probe demonstrated a faster response than a traditional embedded thermocouple during the engine checkout run.

  14. Measurement and simulation of thermoelectric efficiency for single leg

    SciTech Connect

    Hu, Xiaokai; Yamamoto, Atsushi Ohta, Michihiro; Nishiate, Hirotaka

    2015-04-15

    Thermoelectric efficiency measurements were carried out on n-type bismuth telluride legs with the hot-side temperature at 100 and 150°C. The electric power and heat flow were measured individually. Water coolant was utilized to maintain the cold-side temperature and to measure heat flow out of the cold side. Leg length and vacuum pressure were studied in terms of temperature difference across the leg, open-circuit voltage, internal resistance, and heat flow. Finite-element simulation on thermoelectric generation was performed in COMSOL Multiphysics, by inputting two-side temperatures and thermoelectric material properties. The open-circuit voltage and resistance were in good agreement between the measurement and simulation. Much larger heat flows were found in measurements, since they were comprised of conductive, convective, and radiative contributions. Parasitic heat flow was measured in the absence of bismuth telluride leg, and the conductive heat flow was then available. Finally, the maximum thermoelectric efficiency was derived in accordance with the electric power and the conductive heat flow.

  15. Miniature Fixed-Point Cell Approaches for Monitoring of Thermocouple Stability

    NASA Astrophysics Data System (ADS)

    Failleau, G.; Elliott, C. J.; Deuzé, T.; Pearce, J. V.; Machin, G.; Sadli, M.

    2014-07-01

    In the framework of the European Metrology Research Project ENG08 "MetroFission," LNE-Cnam and NPL have undertaken cooperative research into the development of temperature measurement solutions for the next generation of nuclear fission power plants. Currently, in-pile temperature monitoring is usually performed with nickel-based (Type K or N) thermocouples. When these thermocouples are exposed to a neutron flux, the thermoelements transmute, leading to large and unknown drifts in output. In addition, it is impossible to routinely recalibrate the thermocouples after irradiation for obvious reasons of safety. To alleviate this problem, both LNE-Cnam and NPL have developed, via differing approaches, in situ calibration methods for the thermocouples. The self-validating thermocouple methodologies are based on the principle of a miniature fixed-point cell to be co-located with the thermocouple measurement junction in use. The drift of the thermocouple can be monitored and corrected for by regular determination of the output at the phase transition of the fixed-point material: in effect performing regular in situ calibration checks. The two institutes have constructed miniature fixed-point cells for use at three different temperatures; the freezing point of silver ; LNE-Cnam), the freezing point of copper ; LNE-Cnam and NPL), and the melting point of Fe-C (; NPL). This paper introduces the construction and validation of the miniature fixed-point cells prior to use, to ensure traceability to the ITS-90. A comparison of the performance of the two cell designs is discussed, where typical industrial Type N thermocouples have been used for measurement of the fixed-point cells. Such initial measurements demonstrate the feasibility of each of these two approaches.

  16. Film Thickness Influences on the Thermoelectric Properties of NiCr/NiSi Thin Film Thermocouples

    NASA Astrophysics Data System (ADS)

    Chen, Y. Z.; Jiang, H. C.; Zhang, W. L.; Liu, X. Z.; Jiang, S. W.

    2013-06-01

    NiCr/NiSi thin film thermocouples (TFTCs) with a multi-layer structure were fabricated on Ni-based superalloy substrates (95 mm × 35 mm × 2 mm) by magnetron sputtering and electron beam evaporation. The five-layer structure is composed of NiCrAlY buffer layer (2 μm), thermally grown Al2O3 bond layer (200 nm), Al2O3 insulating layer (10 μm), NiCr/NiSi TFTCs (1 μm), and Al2O3 protective layer (500 nm). Influences of thermocouple layer thickness on thermoelectric properties were investigated. Seebeck coefficient of the samples with the increase in thermocouple layer thickness from 0.5 μm to 1 μm increased from 27.8 μV/°C to 33.8 μV/°C, but exhibited almost no change with further increase in thermocouple layer thickness from 1 μm to 2 μm. Dependence on temperature of the thermal electromotive force of the samples almost followed standard thermocouple characteristic curves when the thickness of the thermocouple layer was 1 μm and 2 μm. Sensitive coefficient K of the samples increased greatly with the increase in thickness of the thermocouple layer from 0.5 μm to 1 μm, but decreased insignificantly with the increase in thermocouple layer thickness from 1 μm to 2 μm, and continuously decreased with the increase in temperature. The sensitive coefficient and the stability of NiCr/NiSi TFTCs were both improved after annealing at 600°C.

  17. Thermocouples in an alternating magnetic field (AMF) for studying magnetic nanoparticle hyperthermia

    NASA Astrophysics Data System (ADS)

    Hartzell, S.; Boekelheide, Z.

    Magnetic nanoparticle hyperthermia, a method of cancer therapy, is currently a subject of active research. A critical parameter during therapy or laboratory research is the temperature of the system (tissue or nanoparticle suspension). Thermocouples are affordable and ubiquitous temperature sensors which could be used in this capacity; however, their metallic nature results in self-heating due to eddy currents when placed in an AMF. This presentation will quantitatively discuss calculations and measurements of the self-heating of three common types of thermocouples. Type T, K, and E thermocouples of both thin (40 gauge) and thick (20 gauge) wires were tested in a range of applied magnetic field magnitudes (235 kHz, 0-0.4 T rms). Among the thermocouples, all three types demonstrated large self-heating in 20 gauge wires. For the 40 gauge wires, type K showed large self-heating, while type T showed small but significant self-heating and type E showed no significant self-heating in comparison to the background. Our results indicate that thin type E thermocouples can be accurately used as temperature sensors in an AMF environment similar to the one used here, and type T thermocouples may be appropriate under conditions with lower magnetic field strength or frequency.

  18. Development of a smart temperature measurement system based on a self-calibrating thermocouple

    SciTech Connect

    Ruppel, F.R.

    1989-04-01

    A smart temperature measurement system was developed that consists of a commercially available self-calibrating thermocouple (a thermocouple with a high-purity, low melting-point metal encapsulated near the thermojunction) connected to a data acquisition system with a specially designed algorithm capable of automatically detecting the calibration temperature of the self-calibrating thermocouple. A variety of self-calibrating thermocouples withstood long-term integrity testing, proving their worthiness as a front end to a smart temperature measurement system. A computer simulation program was written to explain the thermodynamic behavior of the system. Based on a literature review and simulation analysis, a method was developed to recognize which point on the melting or freezing plateau curve is the phase transition temperature of the encapsulated metal. The actual phase transition temperature is compared with the experimentally reported melting or freezing point of the encapsulated metal of the self-calibrating thermocouple to determine the magnitude of error in the thermocouple output. 25 refs., 29 figs.

  19. High reliability sheathed, beryllia insulated, tungsten-rhenium alloy thermocouple assemblies; their fabrication and EMF stability

    NASA Technical Reports Server (NTRS)

    Burns, G. W.; Hurst, W. S.; Scroger, M. G.

    1974-01-01

    Tantalum sheathed, BeO insulated, W-3% Re/W-25% Re thermocouple assemblies were fabricated and their emf drift determined during 2059 hours of exposure at 2073 K in a gaseous helium environment. The sheathed thermocouple assemblies were constructed from aged thermoelements, specially heat-treated BeO insulators, and specially cleaned and etched tantalum sheaths. Their thermal emf drifts ranged from the equivalent of only -0.3 to -0.8 K drift per 1000 hours of exposure at 2073 K. No evidence of any gross chemical attack or degradation of the component materials was found. The emf drift and material behavior of some unsheathed, BeO insulated, W-3% Re/W-25% Re thermocouples at 2250 and 2400 K were also determined. Unsheathed thermocouples tested in an argon environment at 2250 K for 1100 hours and at 2400 K for 307 hours exhibited changes in thermal emf that typically ranged from the equivalent of a few degrees K to as much as +11 K. Post-test examinations of these thermocouples revealed some undesirable material degradation and interaction which included erosion of the BeO insulators and contamination of the thermoelements by tantalum from the tantalum blackbody enclosure in which the thermocouples were contained.

  20. Attachment of Free Filament Thermocouples for Temperature Measurements on CMC

    NASA Technical Reports Server (NTRS)

    Lei, Jih-Fen; Cuy, Michael D.; Wnuk, Stephen P.

    1997-01-01

    Ceramic Matrix Composites (CMC) are being developed for use as enabling materials for advanced aeropropulsion engine and high speed civil transport applications. The characterization and testing of these advanced materials in hostile, high-temperature environments require accurate measurement of the material temperatures. Commonly used wire Thermo-Couples (TC) can not be attached to this ceramic based material via conventional spot-welding techniques. Attachment of wire TC's with commercially available ceramic cements fail to provide sufficient adhesion at high temperatures. While advanced thin film TC technology provides minimally intrusive surface temperature measurement and has good adhesion on the CMC, its fabrication requires sophisticated and expensive facilities and is very time consuming. In addition, the durability of lead wire attachments to both thin film TC's and the substrate materials requires further improvement. This paper presents a newly developed attachment technique for installation of free filament wire TC's with a unique convoluted design on ceramic based materials such as CMC's. Three CMC's (SiC/SiC CMC and alumina/alumina CMC) instrumented with type IC, R or S wire TC's were tested in a Mach 0.3 burner rig. The CMC temperatures measured from these wire TC's were compared to that from the facility pyrometer and thin film TC's. There was no sign of TC delamination even after several hours exposure to 1200 C. The test results proved that this new technique can successfully attach wire TC's on CMC's and provide temperature data in hostile environments. The sensor fabrication process is less expensive and requires very little time compared to that of the thin film TC's. The same installation technique/process can also be applied to attach lead wires for thin film sensor systems.

  1. Mixing Hot and Cold Water Streams at a T-Junction

    ERIC Educational Resources Information Center

    Sharp, David; Zhang, Mingqian; Xu, Zhenghe; Ryan, Jim; Wanke, Sieghard; Afacan, Artin

    2008-01-01

    A simple mixing of a hot- and cold-water stream at a T-junction was investigated. The main objective was to use mass and energy balance equations to predict mass low rates and the temperature of the mixed stream after the T-junction, and then compare these with the measured values. Furthermore, the thermocouple location after the T-junction and…

  2. INITIAL RESULTS FROM INVESTIGATIONS TO ENHANCE THE PERFORMANCE OF HIGH TEMPERATURE IRRADIATION-RESISTANT THERMOCOUPLES

    SciTech Connect

    Crepeau, John; Rempe, Joy; Wilkins, S. Curtis; Knudson, Darrell L.; Condie, Keith G.; Daw, Joshua

    2007-04-01

    New fuel, cladding, and structural materials offer the potential for safer and more economic energy from existing reactor and advanced nuclear reactor designs. However, insufficient data are available to characterize these materials in high temperature, radiation conditions. To evaluate candidate material performance, robust instrumentation is needed that can survive these conditions. However, traditional thermocouples either drift due to degradation at high temperatures (above 1100 °C) or due to transmutation of thermocouple components. Thermocouples are needed which can withstand both high temperature and high radiation environments. To address this instrumentation need, the Idaho National Laboratory (INL) recently developed the design and evaluated the performance of a high temperature radiation-resistant thermocouple that contains commercially-available alloys of molybdenum and niobium (Rempe, 2006). Candidate thermocouple component materials were first identified based on their ability to withstand high temperature and radiation. Then, components were selected based on data obtained from materials interaction tests, ductility investigations, and resolution evaluations. Results from long duration (over 4000 hours) tests at high temperatures (up to 1400 °C) and thermal cycling tests demonstrate the stability and reliability of the INL-developed design. Tests in INL’s Advanced Test Reactor (ATR) are underway to demonstrate the in-pile performance of these thermocouples. However, several options have been identified that could further enhance the lifetime and reliability of the INL-developed thermocouples, allowing their use in higher temperature applications (up to at least 1700 °C). A joint University of Idaho (UI) and INL University Nuclear Energy Research Initiative (UNERI) is underway to investigate these options and ultimately, provide recommendations for an enhanced thermocouple design. This paper presents preliminary results from this UI/INL effort

  3. Leg discomfort: beyond the joints.

    PubMed

    Berger, Douglas

    2014-05-01

    Although simple characterization of discomfort as cramps, heaviness, shooting pains, and so forth can be misleading, history and examination are key to accurate diagnosis. Absence of both dorsalis pedis and posterior tibial pulses strongly suggests peripheral arterial disease (PAD), and the presence of either pulse makes PAD less likely. Hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) are a common cause of lower extremity myalgias. Restless legs syndrome causes nocturnal discomfort but must be distinguished from confounding“mimics." Neurologic causes of leg symptoms include lumbar spinal stenosis, radiculopathy, distal symmetric polyneuropathy, and entrapment neuropathy. Many common causes of leg discomfort can be managed conservatively.

  4. Getting Your Sea Legs

    PubMed Central

    Stoffregen, Thomas A.; Chen, Fu-Chen; Varlet, Manuel; Alcantara, Cristina; Bardy, Benoît G.

    2013-01-01

    Sea travel mandates changes in the control of the body. The process by which we adapt bodily control to life at sea is known as getting one's sea legs. We conducted the first experimental study of bodily control as maritime novices adapted to motion of a ship at sea. We evaluated postural activity (stance width, stance angle, and the kinematics of body sway) before and during a sea voyage. In addition, we evaluated the role of the visible horizon in the control of body sway. Finally, we related data on postural activity to two subjective experiences that are associated with sea travel; seasickness, and mal de debarquement. Our results revealed rapid changes in postural activity among novices at sea. Before the beginning of the voyage, the temporal dynamics of body sway differed among participants as a function of their (subsequent) severity of seasickness. Body sway measured at sea differed among participants as a function of their (subsequent) experience of mal de debarquement. We discuss implications of these results for general theories of the perception and control of bodily orientation, for the etiology of motion sickness, and for general phenomena of perceptual-motor adaptation and learning. PMID:23840560

  5. Comparison of Co-C Eutectic-Point Cells for Thermocouple Calibration Between SP and NMIJ

    NASA Astrophysics Data System (ADS)

    Ogura, H.; Holmsten, M.; Klason, P.

    2015-03-01

    As recently reported, the metal-carbon eutectic points seem to be useful as practical reference points for calibrating thermocouples. The melting temperature of the cobalt-carbon eutectic point (Co-C, is an ideal solution for a reference point being at approximately the middle between the freezing point of copper and the melting point of palladium . In this study, a comparison of reference Co-C cells used for thermocouple calibration service was performed between the Technical Institute of Sweden (SP) and the National Metrology Institute of Japan (NMIJ) by means of two circulating Pt/Pd thermocouples and one circulating Co-C cell in order to investigate the reliability of thermocouple calibration at the Co-C eutectic point. The reference Co-C cell at SP was designed and constructed in the National Physical Laboratory (NPL), and provided to SP, while the reference Co-C cell at NMIJ as well as the circulating cell was designed and constructed at NMIJ. The melting temperature of the reference Co-C cells at SP and NMIJ were evaluated by using the calibrated radiation thermometers at NPL and NMIJ, respectively, prior to the circulation of the thermocouples and the cell between SP and NMIJ. The temperature difference between the reference cells of SP and NMIJ, as measured by means of the circulating thermocouples, was found to be within , while that measured by means of the circulating cell was found to be within . The temperature of reference cells at SP and NMIJ was found to agree within an expanded uncertainty in spite of different temperature traceability chains. This means that the calibration of thermocouples at the Co-C eutectic point was sufficiently reliable.

  6. Assessment of tungsten/rhenium thermocouples with metal-carbon eutectic fixed points up to 1500°C

    SciTech Connect

    Gotoh, M.

    2013-09-11

    Four Type A thermocouples and two Type C thermocouples were calibrated at the Au fixed point and Co-C and Pd-C eutectic fixed points. The thermocouples were exposed to 1330 °C for a total of 100 hours. The maximum drift due to the exposure was found to be 4.8 °C. The fixed-point calibration EMF of these thermocouples deviated by less than 0.86% from the temperature specified by the standards ASTM E230-2003 for Type C and GOSTR 8.585-2001 for Type A. The length of one of Type A thermocouples A52 is longer than the others by 150mm. Making use of this provision it was possible to place annealed part of A52 to the temperature gradient part of calibration arrangement every time. Therefore observed aging effect was as low as 0.5 °C compared to the other thermocouples.

  7. Peripheral artery bypass - leg - discharge

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000239.htm Peripheral artery bypass - leg - discharge To use the sharing features ... this page, please enable JavaScript. You had peripheral artery bypass surgery to re-route the blood supply ...

  8. Restless legs syndrome.

    PubMed

    Miletić, Vladimir; Relja, Maja

    2011-12-01

    Being of the most frequent causes of insomnia, which in the end leads to chronic fatigue, inadequate performance of daily activities, and serious disruption of quality of living, restless legs syndrome (RLS) is nowadays not only a serious medical problem but a socio-economical one as well. Prevalence of the disorder in general population is estimated at 5 to 15%. Family history is positive in over 50% of idiopathic RLS patients which points to genetic basis of the disorder. The characteristics of the secondary or acquired form of RLS are symptoms that start later in life as well as a rapid progression of the disease. On the other hand, idiopathic RLS more often starts at a younger age and the prognoses are better. Over twenty disorders and conditions are brought in connection with secondary RLS. Although the cause of primary RLS is still unknown, there is a strong connection between central metabolism of iron as well as dopamine levels and RLS manifestation. A differential diagnosis of RLS includes a wide specter of motor and sensory disorders. Diagnosis is based on clinical features and the history of disease. To correctly diagnose idiopathic RLS one must first eliminate secondary causes of RLS and then also exclude any disorders with clinical features that mimic those of RLS. It has been estimated that some 20 to 25% of patients need pharmacological therapy. Best initial therapy is the application of nonergot dopamine agonists. Anticonvulsants, benzodiazepines and opioides can be given to patients who are refractory to dopaminergic therapy, those suffering from RLS with emphasized painful sensory component and those with RLS connected with insomnia.

  9. The Influence of Size Effect on Sensitivity of Cu/CuNi Thin- film Thermocouple

    NASA Astrophysics Data System (ADS)

    Yang, Lihong; Zhao, Yuanshen; Feng, Cenming; Zhou, Hua

    In this paper, the influence of size effect on the sensitivity of Cu/CuNi thin-film thermocouple was studied through experiments and theoretical analysis. Cu/CuNi thin-film thermocouples with different thicknesses of 0.5 μm, 1.0 μm, 1.5 μm and 2.0 μm were fabricated on the substrate with SiO2 lining by means of reactive magnetron sputtering. After static calibration, the sensitivities of the thermocouples were obtained respectively of 46.49 μV/°C, 45.23 μ/°C, 44.56 μV/°C and 43.94 μV/°C. According to the experimental results, it can be seen that the sensitivity of Cu/CuNi thin-film thermocouple is higher than that of the bulk Cu/CuNi thermocouple, and the sensitivity S will increase with the reciprocal of the thickness 1/δ as long as the thickness of the film is greater than the critical value.

  10. Modeling a self-calibrating thermocouple for use in a smart temperature measurement system

    SciTech Connect

    Ruppel, F.R.

    1989-01-01

    A smart temperature measurement system was developed that consists of a commercially available self-calibrating thermocouple connected to a data-acquisition system with a specially designed algorithm capable of automatically detecting the calibration temperature of the self-calibrating thermocouple. The self-calibrating thermocouple has a high-purity, low melting point metal encapsulated near its thermojunction. The time-temperature record of the thermocouple forms a plateau at the phase transition temperature of the encapsulated metal, providing a single-point calibration. Since the plateau is usually not horizontal, a major effort of the work reported here was to determine which point of the phase transition plateau is the actual phase transition temperature. A finite difference computer simulation program was written to explain the thermodynamic behavior of the system. Based on a literature review and simulation analysis, a method was developed to recognize which point on the melting or freezing plateau curve is the actual phase transition temperature of the encapsulated metal. The known phase transition temperature is compared to the reported melting or freezing point of the encapsulated metal to determine the magnitude of error in the thermocouple output. 10 refs., 12 figs.

  11. Instruments and Methods A physically based method for correcting temperature profile measurements made using thermocouples

    NASA Astrophysics Data System (ADS)

    Cathles, L. Maclagan, IV; Cathles, L. M., III; Albert, M. R.

    High-frequency (diurnal) temperature variations occur simultaneously at multiple depths separated by meters of snow in at least several and probably many Arctic and Antarctic thermocouple datasets. These temperature variations cannot be caused by heat conduction from the surface because their amplitudes are too large and there is no phase lag with depth, and they cannot be caused by heat advection because the air flux required is greater than is available. Rather, the simultaneous temperature variations (STVs) appear to originate within the box that houses the data logger as thermocouple-like offset voltages, wire heating or thermistor error. The STVs can be corrected by requiring that the temperatures vary smoothly with time at the greatest depth at which temperature is measured. The correction voltage determined in this fashion, when applied to the thermocouples at other depths, corrects the entire dataset. The method successfully removes STVs with 24 hour period that are up to 3.8°C in amplitude, and is superior to the averaging techniques commonly used to correct thermocouple data because it introduces no spurious (non-physical) temperature variations. The correction method described can be applied to all thermocouple data where temperature measurements have been made at depths > ˜0.5 m into the snowpack. The corrections should allow more physical process and parameter information to be extracted more confidently from existing firn temperature data. Identification of the STVs and their probable cause also suggests how better data might be collected in the future.

  12. [Problems of using a thermocouple for measurements of skin temperature rise during the exposure to millimeter waves].

    PubMed

    Alekseev, S I; Ziskin, M S; Fesenko, E E

    2011-01-01

    The possibility of using thermocouples for the artifact-free measurements of skin temperature during millimeter wave exposure was studied. The distributions of the specific absorption rate (SAR) in the human skin were calculated for different orientations of the thermocouple relative to the E-field of exposure. It was shown that, at the parallel orientation of a thermocouple relative to the E-field, SAR significantly increased at the tip of the thermocouple. This can result in an overheating of the thermocouple. At the perpendicular orientation of a thermocouple, the distortions of the SAR were insignificant. The data obtained confirm that the skin temperature can be measured with a thermocouple during exposure under the condition that the thermocouple is located perpendicular to the E-vector of the electromagnetic field. For the accurate determination of SAR from the rate of the initial temperature rise, it is necessary to fit the temperature kinetics measured with the thermocouple to the solution of the bio-heat transfer equation.

  13. Cold injuries.

    PubMed

    Kruse, R J

    1995-01-01

    There are two categories of cold injury. The first is hypothermia, which is a systemic injury to cold, and the second is frostbite, which is a local injury. Throughout history, entire armies, from George Washington to the Germans on the Russian Front in World War II, have fallen prey to prolonged cold exposure. Cold injury is common and can occur in all seasons if ambient temperature is lower than the core body temperature. In the 1985 Boston Marathon, even though it was 76 degrees and sunny, there were 75 runners treated for hypothermia. In general, humans adapt poorly to cold exposure. Children are at particular risk because of their relatively greater surface area/body mass ratio, causing them to cool even more rapidly than adults. Because of this, the human's best defense against cold injury is to limit his/her exposure to cold and to dress appropriately. If cold injury has occurred and is mild, often simple passive rewarming such as dry blankets and a warm room are sufficient treatment.

  14. Restless Legs Syndrome and Leg Motor Restlessness in Parkinson's Disease

    PubMed Central

    Suzuki, Keisuke; Miyamoto, Masayuki; Miyamoto, Tomoyuki; Hirata, Koichi

    2015-01-01

    Sleep disturbances are important nonmotor symptoms in Parkinson's disease (PD) that are associated with a negative impact on quality of life. Restless legs syndrome (RLS), which is characterized by an urge to move the legs accompanied by abnormal leg sensations, can coexist with PD, although the pathophysiology of these disorders appears to be different. RLS and PD both respond favorably to dopaminergic treatment, and several investigators have reported a significant relationship between RLS and PD. Sensory symptoms, pain, motor restlessness, akathisia, and the wearing-off phenomenon observed in PD should be differentiated from RLS. RLS in PD may be confounded by chronic dopaminergic treatment; thus, more studies are needed to investigate RLS in drug-naïve patients with PD. Recently, leg motor restlessness (LMR), which is characterized by an urge to move the legs that does not fulfill the diagnostic criteria for RLS, has been reported to be observed more frequently in de novo patients with PD than in age-matched healthy controls, suggesting that LMR may be a part of sensorimotor symptoms intrinsic to PD. In this paper, we provide an overview of RLS, LMR, and PD and of the relationships among these disorders. PMID:26504610

  15. Improving the dependability of critical thermocouple thermometry for fossil-fuel gasifiers and retorts

    NASA Astrophysics Data System (ADS)

    Reed, R. P.

    1982-07-01

    Critical thermocouple thermometry is such a measurement in which either excessive error or loss of signal can result in unacceptable consequences. To avoid these consequences it is necessary that the thermometry survive whatever adverse environment accompanies the measurement; however, it is just as essential to accomplish definite, adequate, demonstrated accuracy. This report describes some of the more significant problems involved in applying thermocouple thermometry in hostile environments. For example a hostile environment is encountered in some locations in gasifiers and retorts; there sensor damage is likely. A model of defective thermocouples is used to describe several damage mechanisms, their effects on dependability, and the symptoms that allow their detection. The model illustrates why many significant errors can occur unrecognized and demonstrates the practical need for real-time validation diagnostics. Special continual diagnostic techniques are described that can help to establish the dependability of critical measurement throughout the period of use.

  16. Printed organic conductive polymers thermocouples in textile and smart clothing applications.

    PubMed

    Seeberg, Trine M; Røyset, Arne; Jahren, Susannah; Strisland, Frode

    2011-01-01

    This work reports on an experimental investigation of the potential of using selected commercially available organic conductive polymers as active ingredients in thermocouples printed on textiles. Poly(3, 4-ethylenedioxythiophene): poly(4 styrenesulfonate) (PEDOT:PSS) and polyaniline (PANI) were screen printed onto woven cotton textile. The influence of multiple thermocycles between 235 K (-38 °C) and 350 K (+77 °C) on resistivity and thermoelectric properties was examined. The Seebeck coefficients of PEDOT:PSS and PANI were found to be about +18 μV/K and +15 uV/K, respectively, when "metal-polymer" thermocouples were realized by combining the polymer with copper. When "polymer-polymer" thermocouples were formed by combining PEDOT:PSS and PANI, a thermoelectric voltage of about +10 μV/K was observed. A challenge recognized in the experiments is that the generated voltage exhibited drift and fluctuations.

  17. Prototype thin-film thermocouple/heat-flux sensor for a ceramic-insulated diesel engine

    NASA Technical Reports Server (NTRS)

    Kim, Walter S.; Barrows, Richard F.

    1988-01-01

    A platinum versus platinum-13 percent rhodium thin-film thermocouple/heat-flux sensor was devised and tested in the harsh, high-temperature environment of a ceramic-insulated, low-heat-rejection diesel engine. The sensor probe assembly was developed to provide experimental validation of heat transfer and thermal analysis methodologies applicable to the insulated diesel engine concept. The thin-film thermocouple configuration was chosen to approximate an uninterrupted chamber surface and provide a 1-D heat-flux path through the probe body. The engine test was conducted by Purdue University for Integral Technologies, Inc., under a DOE-funded contract managed by NASA Lewis Research Center. The thin-film sensor performed reliably during 6 to 10 hr of repeated engine runs at indicated mean surface temperatures up to 950 K. However, the sensor suffered partial loss of adhesion in the thin-film thermocouple junction area following maximum cyclic temperature excursions to greater than 1150 K.

  18. Direct measurements of electrocaloric effect in ferroelectrics using thin-film thermocouples

    NASA Astrophysics Data System (ADS)

    Matsushita, Yuji; Nochida, Atsushi; Yoshimura, Takeshi; Fujimura, Norifumi

    2016-10-01

    A direct measurement method for investigating the electrocaloric (EC) effect was developed using a thin-film thermocouple deposited on samples. A T-type thin-film thermocouple was fabricated by RF magnetron sputtering at room temperature. Two types of measurement were carried out using rectangular pulses and sine waves with a DC offset. The EC coefficients (ΔT/ΔE) of BaTiO3 ceramics were determined as 0.35 × 10-6 and 0.48 × 10-6 K·m/V in the measurements at Curie temperature. The EC temperature change of a (Ba0.9,Ca0.1)TiO3 thin film was measured using sine waves with the DC offset. The EC coefficient was 0.0018 × 10-6 K·m/V at room temperature. These results suggest that thin-film thermocouples are useful for the direct measurement of the EC effect.

  19. Difference equation approach to two-thermocouple sensor characterization in constant velocity flow environments

    NASA Astrophysics Data System (ADS)

    Hung, P. C.; Irwin, G.; Kee, R.; McLoone, S.

    2005-02-01

    Thermocouples are one of the most popular devices for temperature measurement due to their robustness, ease of manufacture and installation, and low cost. However, when used in certain harsh environments, for example, in combustion systems and engine exhausts, large wire diameters are required, and consequently the measurement bandwidth is reduced. This article discusses a software compensation technique to address the loss of high frequency fluctuations based on measurements from two thermocouples. In particular, a difference equation (DE) approach is proposed and compared with existing methods both in simulation and on experimental test rig data with constant flow velocity. It is found that the DE algorithm, combined with the use of generalized total least squares for parameter identification, provides better performance in terms of time constant estimation without any a priori assumption on the time constant ratios of the thermocouples.

  20. Frequency response of a supported thermocouple wire: Effects of axial conduction

    NASA Technical Reports Server (NTRS)

    Forney, L. J.; Meeks, E. L.; Fralick, G. C.

    1991-01-01

    Theoretical expressions are derived for the steady-state frequency response of a supported thermocouple wire. In particular, the effects of axial heat conduction are demonstrated for both a supported one material wire and a two material wire with unequal material properties across the junction. For the case of a one material supported wire, an exact solution is derived which compares favorably with an approximate expression that only matches temperatures at the support junction. Moreover, for the case of a two material supported wire, an analytical expression is derived that closely correlates numerical results. Experimental data were taken with a type K supported thermocouple. The test thermocouple was constructed with dimensions to demonstrate the effects of axial heat conduction assuming constant physical properties across the junction.

  1. Thermocouple error correction for measuring the flame temperature with determination of emissivity and heat transfer coefficient.

    PubMed

    Hindasageri, V; Vedula, R P; Prabhu, S V

    2013-02-01

    Temperature measurement by thermocouples is prone to errors due to conduction and radiation losses and therefore has to be corrected for precise measurement. The temperature dependent emissivity of the thermocouple wires is measured by the use of thermal infrared camera. The measured emissivities are found to be 20%-40% lower than the theoretical values predicted from theory of electromagnetism. A transient technique is employed for finding the heat transfer coefficients for the lead wire and the bead of the thermocouple. This method does not require the data of thermal properties and velocity of the burnt gases. The heat transfer coefficients obtained from the present method have an average deviation of 20% from the available heat transfer correlations in literature for non-reacting convective flow over cylinders and spheres. The parametric study of thermocouple error using the numerical code confirmed the existence of a minimum wire length beyond which the conduction loss is a constant minimal. Temperature of premixed methane-air flames stabilised on 16 mm diameter tube burner is measured by three B-type thermocouples of wire diameters: 0.15 mm, 0.30 mm, and 0.60 mm. The measurements are made at three distances from the burner tip (thermocouple tip to burner tip/burner diameter = 2, 4, and 6) at an equivalence ratio of 1 for the tube Reynolds number varying from 1000 to 2200. These measured flame temperatures are corrected by the present numerical procedure, the multi-element method, and the extrapolation method. The flame temperatures estimated by the two-element method and extrapolation method deviate from numerical results within 2.5% and 4%, respectively.

  2. Printable tiny thermocouple by liquid metal gallium and its matching metal

    NASA Astrophysics Data System (ADS)

    Li, Haiyan; Yang, Yang; Liu, Jing

    2012-08-01

    Direct printing of thermocouples by the liquid metal was proposed. The fabricated temperature sensor composed of gallium and its matching metal exhibited excellent linear dependence between thermoelectric voltage and temperature within the range from 0 to 200 °C. Further, it was disclosed that liquid metals with high purity could be used for high precision thermocouples with tiny size, which were quite convenient to be used in micro channel measurement due to their fluidity in making sensors; while liquid metals with a small amount of oxides were handy for depositing on the substrate by "hand-written" style, with thin film thickness of approximately 50 μm.

  3. Pipe crawler with extendable legs

    DOEpatents

    Zollinger, W.T.

    1992-06-16

    A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long as a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler. 8 figs.

  4. Pipe crawler with extendable legs

    DOEpatents

    Zollinger, William T.

    1992-01-01

    A pipe crawler for moving through a pipe in inchworm fashion having front and rear leg assemblies separated by air cylinders to increase and decrease the spacing between assemblies. Each leg of the four legs of an assembly is moved between a wall-engaging, extended position and a retracted position by a separate air cylinder. The air cylinders of the leg assemblies are preferably arranged in pairs of oppositely directed cylinders with no pair lying in the same axial plane as another pair. Therefore, the cylinders can be as long a leg assembly is wide and the crawler can crawl through sections of pipes where the diameter is twice that of other sections. The crawler carries a valving system, a manifold to distribute air supplied by a single umbilical air hose to the various air cylinders in a sequence controlled electrically by a controller. The crawler also utilizes a rolling mechanism, casters in this case, to reduce friction between the crawler and pipe wall thereby further extending the range of the pipe crawler.

  5. Prometheus Hot Leg Piping Concept

    NASA Astrophysics Data System (ADS)

    Gribik, Anastasia M.; DiLorenzo, Peter A.

    2007-01-01

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  6. Promethus Hot Leg Piping Concept

    SciTech Connect

    AM Girbik; PA Dilorenzo

    2006-01-24

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  7. Prometheus Hot Leg Piping Concept

    SciTech Connect

    Gribik, Anastasia M.; DiLorenzo, Peter A.

    2007-01-30

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept.

  8. Intramuscular pressures beneath elastic and inelastic leggings

    NASA Technical Reports Server (NTRS)

    Murthy, G.; Ballard, R. E.; Breit, G. A.; Watenpaugh, D. E.; Hargens, A. R.

    1994-01-01

    Leg compression devices have been used extensively by patients to combat chronic venous insufficiency and by astronauts to counteract orthostatic intolerance following spaceflight. However, the effects of elastic and inelastic leggings on the calf muscle pump have not been compared. The purpose of this study was to compare in normal subjects the effects of elastic and inelastic compression on leg intramuscular pressure (IMP), an objective index of calf muscle pump function. IMP in soleus and tibialis anterior muscles was measured with transducer-tipped catheters. Surface compression between each legging and the skin was recorded with an air bladder. Subjects were studied under three conditions: (1) control (no legging), (2) elastic legging, and (3) inelastic legging. Pressure data were recorded for each condition during recumbency, sitting, standing, walking, and running. Elastic leggings applied significantly greater surface compression during recumbency (20 +/- 1 mm Hg, mean +/- SE) than inelastic leggings (13 +/- 2 mm Hg). During recumbency, elastic leggings produced significantly higher soleus IMP of 25 +/- 1 mm Hg and tibialis anterior IMP of 28 +/- 1 mm Hg compared to 17 +/- 1 mm Hg and 20 +/- 2 mm Hg, respectively, generated by inelastic leggings and 8 +/- 1 mm Hg and 11 +/- 1 mm Hg, respectively, without leggings. During sitting, walking, and running, however, peak IMPs generated in the muscular compartments by elastic and inelastic leggings were similar. Our results suggest that elastic leg compression applied over a long period in the recumbent posture may impede microcirculation and jeopardize tissue viability.(ABSTRACT TRUNCATED AT 250 WORDS).

  9. Cold intolerance

    MedlinePlus

    Some causes of cold intolerance are: Anemia Anorexia nervosa Blood vessel problems, such as Raynaud phenomenon Chronic severe illness General poor health Underactive thyroid ( hypothyroidism ) Problem with the hypothalamus (a part ...

  10. Long term out-of-pile thermocouple tests in conditions representative for nuclear gas-cooled high temperature reactors

    SciTech Connect

    Laurie, M.; Fourrez, S.; Fuetterer, M. A.; Lapetite, J. M.

    2011-07-01

    During irradiation tests at high temperature, failure of commercial Inconel 600 sheathed thermocouples is commonly encountered. To understand and remedy this problem, out-of-pile tests were performed with thermocouples in carburizing atmospheres which can be assumed to be at least locally representative for High Temperature Reactors. The objective was to screen those thermocouples which would consecutively be used under irradiation. Two such screening tests have been performed with a set of thermocouples embedded in graphite (mainly conventional Type N thermocouples and thermocouples with innovative sheaths) in a dedicated furnace with helium flushing. Performance indicators such as thermal drift, insulation and loop resistance were monitored and compared to those from conventional Type N thermocouples. Several parameters were investigated: niobium sleeves, bending, thickness, sheath composition, temperature as well as the chemical environment. After the tests, Scanning Electron Microscopy (SEM) examinations were performed to analyze possible local damage in wires and in the sheath. The present paper describes the two experiments, summarizes results and outlines further work, in particular to further analyze the findings and to select suitable thermocouples for qualification under irradiation. (authors)

  11. HYPERTENSIVE-ISCHEMIC LEG ULCERS

    PubMed Central

    Farber, Eugene M.; Schmidt, Otto E. L.

    1950-01-01

    Ischemic ulcers of the leg having characteristics different from those of ordinary leg ulcers have been observed in a small number of hypertensive patients, mostly women, during the past few years. Such ulcers are usually located above the ankle. They begin with a small area of purplish discoloration at the site of slight trauma, and progress to acutely tender ulceration. In studies of tissue removed from the margin and the base of an ulcer of this kind, obliterative arteriolar sclerotic changes, ischemic-appearing connective tissue and inflammatory changes were noted. Two additional cases are reported. ImagesFigure 1.Figure 2.Figure 3.Figure 4. PMID:15398887

  12. Rotigotine for restless legs syndrome.

    PubMed

    Davies, Shelley

    2009-09-01

    Restless legs syndrome (RLS) is a neurological disorder related to abnormal and unpleasant sensations and movements in the legs. It usually occurs at nighttime and thus has a detrimental impact on the ability to sleep, leading to poor patient quality of life. UCB has been developing rotigotine transdermal patch system (Neupro; SPM-962) as a treatment for RLS. This system is designed to replace levels of dopamine in the body via once-daily application of the patch, in a bid to restore proper motor functioning. The rotigotine patch has been authorized for the treatment of RLS since August 2008.

  13. Low drift type N thermocouples in out-of-pile advanced gas reactor mock-up test: metallurgical analysis

    SciTech Connect

    Scervini, M.; Palmer, J.; Haggard, D.C.; Swank, W.D.

    2015-07-01

    Thermocouples are the most commonly used sensors for temperature measurement in nuclear reactors. They are crucial for the control of current nuclear reactors and for the development of GEN IV reactors. In nuclear applications thermocouples are strongly affected by intense neutron fluxes. As a result of the interaction with neutrons, the thermoelements of the thermocouples undergo transmutation, which produces a time dependent change in composition and, as a consequence, a time dependent drift of the thermocouple signal. Thermocouple drift can be very significant for in-pile temperature measurements and may render the temperature sensors unreliable after exposure to nuclear radiation for relatively short times compared to the life required for temperature sensors in nuclear applications. Previous experiences with type K thermocouples in nuclear reactors have shown that they are affected by neutron irradiation only to a limited extent. Similarly type N thermocouples are expected to be only slightly affected by neutron fluxes. Currently the use of Nickel based thermocouples is limited to temperatures lower than 1000 deg. C due to drift related to phenomena other than nuclear irradiation. As part of a collaboration between Idaho National Laboratory (INL) and the University of Cambridge a variety of Type N thermocouples have been exposed at INL in an Advanced Gas Reactor mock-up test at 1150 deg. C for 2000 h, 1200 deg. C for 2000 h, 125 deg. C for 200 h and 1300 deg. C for 200 h, and later analysed metallurgically at the University of Cambridge. The use of electron microscopy allows to identify the metallurgical changes occurring in the thermocouples during high temperature exposure and correlate the time dependent thermocouple drift with the microscopic changes experienced by the thermoelements of different thermocouple designs. In this paper conventional Inconel 600 sheathed type N thermocouples and a type N using a customized sheath developed at the University of

  14. Bilateral Leg Replantation in a 3-Month-Old Baby After a Knee Level Crush Amputation-A 2-Year Follow-up.

    PubMed

    Bulic, Kresimir; Antabak, Anko; Dujmovic, Anto; Kisic, Hrvoje; Lorencin, Mia

    2017-03-01

    We present a case of a successful bilateral leg replantation in a 3-month-old baby after a knee-level crush amputation with the loss of both knee joints. The legs were replanted after 4 hours of warm and an additional 2.5 and 3.5 hours of cold ischemia time. Both legs show motor and sensory reinnervation, without additional procedures performed on the right leg, and after a nerve reconstruction with cadaveric allografts on the left leg. Both replanted legs exhibit excellent bony and soft tissue growth. Two years after the injury, the patient is progressing well with rehabilitation, with favourable odds of having knee reconstructions performed at a later age. This is the youngest patient reported to have had successful replantation of both legs.

  15. Performance and Durability of Thin Film Thermocouple Array on a Porous Electrode

    PubMed Central

    Guk, Erdogan; Ranaweera, Manoj; Venkatesan, Vijay; Kim, Jung-Sik

    2016-01-01

    Management of solid oxide fuel cell (SOFC) thermal gradients is vital to limit thermal expansion mismatch and thermal stress. However, owing to harsh operation conditions of SOFCs and limited available space in stack configuration, the number of techniques available to obtain temperature distribution from the cell surface is limited. The authors previously developed and studied a thermocouple array pattern to detect surface temperature distribution on an SOFC in open circuit conditions. In this study, the performance in terms of mechanical durability and oxidation state of the thin film thermoelements of the thermocouple array on the porous SOFC cathode is investigated. A thin-film multi-junction thermocouple array was sputter deposited using a magnetron sputter coater. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) characterisation techniques were carried out to understand characteristics of the thin film before and after temperature (20 °C–800 °C) measurement. Temperature readings from the sensor agreed well with the closely placed commercial thermocouple during heating segments. However, a sensor failure occurred at around 350 °C during the cooling segment. The SEM and XPS tests revealed cracks on the thin film thermoelements and oxidation to the film thickness direction. PMID:27563893

  16. In-vessel fluid flow measurements using thermocouples cross-correlation.

    SciTech Connect

    NguyenLe, Q.

    1998-05-08

    Fluid flow rate in high temperature and pressure vessels can be difficult to measure due to the associated harsh environment, inaccessible locations and pressure boundary integrity concerns. However, by using quick response miniature thermocouples to measure the naturally occurring temperature variations within the flow, the fluid velocity can be inferred from the transit time analysis. This flow measurement technique has other advantages such as the flow profile is not significantly disturbed, no additional flow restrictions introduced and the system fiction factor is not increased. Furthermore, since the measured flow rate is generally unaffected by the global system dynamics, such as heat increases or losses, as well as changes in the flow regimes, the location of the thermocouple pairs is extremely flexible. Due to the mentioned advantages, the thermocouple cross-correlation flow measurement method has been developed for use at the Purdue University Multi-Dimensional Integral Test Assembly (PUMA). Currently, thermocouple cross-correlation technique is used to measure the Reactor Pressure Vessel downcomer fluid velocity and the suppression pool in-vessel natural circulation velocity.

  17. Oxidation-resisting technology of W-Re thermocouples and their industrial applications

    NASA Astrophysics Data System (ADS)

    Wang, K.; Dai, M.; Dong, J.; Wang, L.; Wang, T.

    2013-09-01

    We use DSC/TG, SEM and EPMA approaches to investigate the high temperature oxidation behaviors of the Type C W-Re thermocouple wires and W-Re powders which the wires were made from. To solve the oxidization of W-Re thermocouples the chemical method, other than the commonly used physical method, i.e. vacuum-pumping method, was developed. Several solid-packed techniques such as stuffing with inert material, chemical deoxidizing, gas-absorbing and sealing were employed to prevent the W-Re thermocouples from oxidizing. Based on comprehensive consideration of various parameters in process industries, a series of industrial W-Re thermocouples has been successfully used in oxidizing and reducing atmospheres, high temperature alkali and other harsh environments. The service life is 6 to 12 months in strong oxidizing atmosphere of Cr2O3-Al2O3 brick kiln and 2 to 3 months in high temperature alkali and in reducing atmosphere of CO.

  18. Performance and Durability of Thin Film Thermocouple Array on a Porous Electrode.

    PubMed

    Guk, Erdogan; Ranaweera, Manoj; Venkatesan, Vijay; Kim, Jung-Sik

    2016-08-23

    Management of solid oxide fuel cell (SOFC) thermal gradients is vital to limit thermal expansion mismatch and thermal stress. However, owing to harsh operation conditions of SOFCs and limited available space in stack configuration, the number of techniques available to obtain temperature distribution from the cell surface is limited. The authors previously developed and studied a thermocouple array pattern to detect surface temperature distribution on an SOFC in open circuit conditions. In this study, the performance in terms of mechanical durability and oxidation state of the thin film thermoelements of the thermocouple array on the porous SOFC cathode is investigated. A thin-film multi-junction thermocouple array was sputter deposited using a magnetron sputter coater. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) characterisation techniques were carried out to understand characteristics of the thin film before and after temperature (20 °C-800 °C) measurement. Temperature readings from the sensor agreed well with the closely placed commercial thermocouple during heating segments. However, a sensor failure occurred at around 350 °C during the cooling segment. The SEM and XPS tests revealed cracks on the thin film thermoelements and oxidation to the film thickness direction.

  19. Development and Evaluation of a Co-C Eutectic-Point Cell for Thermocouple Calibration

    NASA Astrophysics Data System (ADS)

    Holmsten, M.; Ogura, H.; Klason, P.; Ljungblad, S.

    2015-08-01

    The cobalt-carbon (Co-C) eutectic point at has in previous studies proved to be suitable as a reference for thermocouple calibration above . For types S, R, and B, it fills the gap between the copper point and the palladium point, and for Pt/Pd thermocouples, it extends the range from the copper point. This work describes the implementation of the Co-C reference point at the Technical Institute of Sweden (SP). A Co-C cell was developed and manufactured at SP in a collaboration project with the National Metrology Institute of Japan (NMIJ). The principle of the cell is a hybrid design with double walls, both for the outer crucible and the inner thermometer well, with graphite foil between the walls. To evaluate the performance of the developed cell (SP cell), a comparison between the SP cell and another cell, manufactured and provided from the National Physics Laboratory (NPL) in England, is performed using Pt/Pd thermocouples as transfer standards. The comparison showed very good agreement, with differences below 40 mK, using the same furnace and two different thermocouples. The expanded uncertainty for the comparison was estimated to be 70 mK.

  20. Measuring skin temperature before, during and after exercise: a comparison of thermocouples and infrared thermography.

    PubMed

    Fernandes, Alex de Andrade; Amorim, Paulo Roberto dos Santos; Brito, Ciro José; de Moura, Anselmo Gomes; Moreira, Danilo Gomes; Costa, Carlos Magno Amaral; Sillero-Quintana, Manuel; Marins, João Carlos Bouzas

    2014-02-01

    Measuring skin temperature (TSK) provides important information about the complex thermal control system and could be interesting when carrying out studies about thermoregulation. The most common method to record TSK involves thermocouples at specific locations; however, the use of infrared thermal imaging (IRT) has increased. The two methods use different physical processes to measure TSK, and each has advantages and disadvantages. Therefore, the objective of this study was to compare the mean skin temperature (MTSK) measurements using thermocouples and IRT in three different situations: pre-exercise, exercise and post-exercise. Analysis of the residual scores in Bland-Altman plots showed poor agreement between the MTSK obtained using thermocouples and those using IRT. The averaged error was -0.75 °C during pre-exercise, 1.22 °C during exercise and -1.16 °C during post-exercise, and the reliability between the methods was low in the pre- (ICC = 0.75 [0.12 to 0.93]), during (ICC = 0.49 [-0.80 to 0.85]) and post-exercise (ICC = 0.35 [-1.22 to 0.81] conditions. Thus, there is poor correlation between the values of MTSK measured by thermocouples and IRT pre-exercise, exercise and post-exercise, and low reliability between the two forms of measurement.

  1. Modeling a self-calibrating thermocouple for use in a smart temperature measurement system

    SciTech Connect

    Ruppel, F.R. )

    1990-12-01

    A finite-difference computer-simulation program was developed to explain the thermodynamic behavior of the self-calibrating thermocouple. Based on a literature review and simulation analysis, a method was developed to recognize which point on the time-temperature curve is the calibration point. A description of the model and results of parametric studies are given.

  2. A computer-controlled apparatus for Seebeck inhomogeneity testing of sheathed thermocouples

    NASA Technical Reports Server (NTRS)

    Burkett, Cecil G., Jr.; Bauserman, Willard A., Jr.

    1993-01-01

    Mineral-insulated metal-sheathed (MIMS) thermocouple assemblies are used throughout industry and research facilities as a method of temperature measurement where requirements for either harsh environmental conditions exist, or where rigidity of the measurement probe is required. Seebeck inhomogeneity is the abnormal variation of the Seebeck coefficient from point to point in a material. It is not disclosed in conventional calibration. A standardized method of measuring thermoelectric inhomogeneity along the thermocouple probe length is not available. Therefore, calibration for sheathed probes normally does not include testing of probe inhomogeneity. The measurement accuracy would be severely impacted if significant inhomogeneity and a temperature gradient were present in the same region of the probe. A computer-controlled system for determining inhomogeneities was designed, fabricated, and tested. This system provides an accurate method for the identification of the location of inhomogeneity along the length of a sheathed thermocouple and for the quantification of the inhomogeneity. This paper will discuss the apparatus and procedure used to perform these tests and will present data showing tests performed on sheathed thermocouple probes.

  3. National Inter-laboratory Comparison of Thermocouples in the Temperature Range from to

    NASA Astrophysics Data System (ADS)

    Arifoviç, N.; Kalemci, M.

    2015-08-01

    One of the main criteria demonstrating the competence of a calibration laboratory is successful participation in inter-laboratory comparisons. Real capability of the laboratory including claimed uncertainties could be demonstrated based on the results of comparisons, evaluated either through -criteria or other acceptable measures. As a number of accredited laboratories with scopes covering calibration services in the field of thermometry have been increasing, the demand for organization of inter-laboratory comparisons with participation of accredited laboratories occurs. Based on this fact, a national inter-laboratory comparison of thermocouple calibrations in the temperature range from to in the field of temperature was launched by TUBITAK UME in 2011. The purpose of the inter-laboratory comparison was to compare the results of the participating laboratories during calibration of the thermocouples in the range from to . Three type S thermocouples were constructed and calibrated by TUBITAK UME which is the pilot laboratory of the comparison. It was recommended that the participants use their standard procedure for the calibration of thermocouples and follow the instructions of comparison protocol during the calibration. The inter-laboratory comparison was carried out among eleven national accredited laboratories. In this paper, the temperature differences obtained by participating laboratories with associated uncertainties of the results and values will be presented. The metrological equivalence of all laboratories was demonstrated, with all values being less than 1.0.

  4. Evaluation of Specialized Thermocouples for High-Temperature In-Pile Testing

    SciTech Connect

    J. L. Rempe; D. L. Knudson; K. G. Condie; S. C. Wilkins

    2006-06-01

    Many advanced nuclear reactor designs require new fuel, cladding, and structural materials. Data are needed to characterize the performance of these new materials in high temperature, oxidizing, and radiation conditions. To obtain this data, robust instrumentation is needed that can survive proposed test conditions. Standard thermocuoples for measuring temperature in-pile degrade at temperatures above 1100 ºC. Hence, INL initiated a project to develop specialized thermocouples for high temperature in-pile applications. Results from efforts to develop, fabricate, and evaluate specialized high-temperature thermocouples for in-pile applications suggest that several material combinations are viable. Tests show that several low neutron cross-section candidate materials are resistant to material interactions and remain ductile at high temperatures. In addition, results indicate that the thermoelectric response is singlevalued and repeatable with acceptable resolution for the candidate thermoelements considered. The final selection of the thermocouple materials will depend on the desired peak temperature and accuracy requirements. If thermocouples are needed that measure temperatures at 1600 ºC or higher, the doped Mo / Nb-1%Zr and Mo-1.6% Nb / Nb-1%Zr thermoelement wire combinations are recommended with HfO2 insulation, and a Nb-1%Zr sheath. Additional evaluations are underway to characterize the performance of this proposed thermocouple design. INL has worked to optimize this thermocouple’s stability. With appropriate heat treatment and fabrication approaches, results indicate that the effects of thermal cycling on the calibration of the proposed thermocouple design can be minimized. INL has initiated a series of high temperature (from 1200 to 1800 ºC) long duration (up to six months) tests. Initial results indicate the INL-developed thermocouple’s termoelectric response is stable with less than 15 ºC drift observed in over 3500 hours of the planned 4000 hours

  5. Other Causes of Leg Pain

    MedlinePlus

    ... in the same position for a long time Injuries caused by: A torn or overstretched muscle (strain) Hairline crack in the bone (stress fracture) Inflamed tendon (tendinitis) Shin splints—pain in the front of your leg related to overuse or repetitive pounding Deep vein thrombosis (DVT) , which occurs when ...

  6. FAQs on leg ulcer care.

    PubMed

    Anderson, Irene; King, Brenda; Knight, Susan; Keynes, Milton

    In a webchat on leg ulcer management issues, hosted by Nursing Times, participants raised three key areas of care: the role of healthcare assistants in compression bandaging; reporting and investigating damage caused by compression therapy; and recommendations for dressings to be used under compression. This article discusses each of these in turn.

  7. Rotational joint for prosthetic leg

    NASA Technical Reports Server (NTRS)

    Jones, W. C.; Owens, L. J.

    1977-01-01

    Device is installed in standard 30 millimeter tubing used for lower leg prosthetics. Unit allows proper rotation (about 3 degrees) of foot relative to the hip, during normal walking or running. Limited rotational movement with restoring force results in a more natural gait.

  8. Long-Term Monitoring of Thermocouple Stability with Miniature Fixed-Point Cells

    NASA Astrophysics Data System (ADS)

    Elliott, C. J.; Failleau, G.; Deuzé, T.; Sadli, M.; Pearce, J. V.; Machin, G.

    2014-04-01

    In the framework of the European Metrology Research Programme ENG08 "MetroFission" project, two National Measurement Institutes, LNE-Cnam (France) and NPL (UK), have cooperatively developed methods of in situ validation of thermocouple output for application in next-generation nuclear fission power plants. Miniature fixed-point cells for use at three temperatures were constructed in the first step of this project: at the freezing point of silver (), the freezing point of copper (), and the melting point of the iron-carbon eutectic (). This paper reports the results of a second step in the study, where the robustness of the self-validation method has been investigated. Typical industrial Type N thermocouples have been employed with each of the miniature fixed-point devices installed, and repeatedly thermally cycled through the melting and freezing transitions of the fixed-point ingots. The devices have been exposed to a total of up to 90 h in the molten state. Furthermore, the LNE-Cnam devices were also subjected to fast cool-down rates, on five occasions, where the rate is estimated to have been between and . The devices are shown to be repeatable, reliable, and robust over the course of these tests. The drift of the Type N thermocouple has been identified separately to the behavior of the device. A reliable method for improving thermocouple performance and process control is therefore demonstrated. Requirements for implementation and the advantages of each approach for monitoring and correcting thermocouple drift are discussed, and an uncertainty budget for self-validation is presented.

  9. Cold injuries.

    PubMed

    Long, William B; Edlich, Richard F; Winters, Kathryne L; Britt, L D

    2005-01-01

    Exposure to cold can produce a variety of injuries that occur as a result of man's inability to adapt to cold. These injuries can be divided into localized injury to a body part, systemic hypothermia, or a combination of both. Body temperature may fall as a result of heat loss by radiation, evaporation, conduction, and convection. Hypothermia or systemic cold injury occurs when the core body temperature has decreased to 35 degrees C (95 degrees F) or less. The causes of hypothermia are either primary or secondary. Primary, or accidental, hypothermia occurs in healthy individuals inadequately clothed and exposed to severe cooling. In secondary hypothermia, another illness predisposes the individual to accidental hypothermia. Hypothermia affects multiple organs with symptoms of hypothermia that vary according to the severity of cold injury. The diagnosis of hypothermia is easy if the patient is a mountaineer who is stranded in cold weather. However, it may be more difficult in an elderly patient who has been exposed to a cold environment. In either case, the rectal temperature should be checked with a low-reading thermometer. The general principals of prehospital management are to (1) prevent further heat loss, (2) rewarm the body core temperature in advance of the shell, and (3) avoid precipitating ventricular fibrillation. There are two general techniques of rewarming--passive and active. The mechanisms of peripheral cold injury can be divided into phenomena that affect cells and extracellular fluids (direct effects) and those that disrupt the function of the organized tissue and the integrity of the circulation (indirect effects). Generally, no serious damage is seen until tissue freezing occurs. The mildest form of peripheral cold injury is frostnip. Chilblains represent a more severe form of cold injury than frostnip and occur after exposure to nonfreezing temperatures and damp conditions. Immersion (trench) foot, a disease of the sympathetic nerves and blood

  10. Cold urticaria.

    PubMed

    Claudy, A

    2001-11-01

    Cold urticaria is one form of urticaria that may be associated with other forms of physical urticarias. Frequency is generally estimated at two or three per 100. The triggering effect of cold is found at history taking in most of the cases. The urticaria is usually superficial, and more rarely associated with deep and/or mucosal urticaria. The diagnosis is based on history taking and the ice cube test. An exhaustive search for an etiologic factor is often unfruitful, and the presence of a cryopathy should lead to a complete work-up. Therapy of cold urticaria may prove to be difficult. In patients with secondary cold urticaria, underlying disease must be treated in order to resolve the skin symptoms. H1-antihistamines can be used but the clinical responses are highly variable. Short-time treatment with low concentration corticosteroids suppresses the symptoms only partially and temporarily. In patients who do not respond to previous treatments, induction of cold tolerance may be proposed but the procedure is difficult to carry out in daily life over an extended period. Key word: cryoglobulins.

  11. The one-leg standing radiograph

    PubMed Central

    Naratrikun, K.; Kanitnate, S.; Sangkomkamhang, T.

    2016-01-01

    Objectives The purpose of this study was to compare the joint space width between one-leg and both-legs standing radiographs in order to diagnose a primary osteoarthritis of the knee. Methods Digital radiographs of 100 medial osteoarthritic knees in 50 patients were performed. The patients had undergone one-leg standing anteroposterior (AP) views by standing on the affected leg while a both-legs standing AP view was undertaken while standing on both legs. The severity of the osteoarthritis was evaluated using the joint space width and Kellgren-Lawrence (KL) radiographic classification. The t-test was used for statistical analysis. Results The mean medial joint space width found in the one-leg and in the both-legs standing view were measured at 1.8 mm and 2.4 mm, respectively (p < 0.001, 95% CI 0.5 to 0.7). 33%, 47.4% and 23.1% of the knees diagnosed with a KL grade of I, II and III in the both-legs standing views were changed to KL grade II, III and IV in the one-leg standing views, respectively. No changes for KL IV osteoarthritis diagnoses have been found between both- and one-leg standing views. Conclusions One-leg standing radiographs better represent joint space width than both-legs standing radiographs. 32% of both-legs standing radiographs have changed the KL grading to a more severe grade than that in the one-leg standing radiographs. Cite this article: P. Pinsornsak, K. Naratrikun, S. Kanitnate, T. Sangkomkamhang. The one-leg standing radiograph: An improved technique to evaluate the severity of knee osteoarthritis. Bone Joint Res 2016;5:436–441. DOI: 10.1302/2046-3758.59.BJR-2016-0049.R1. PMID:27683299

  12. COLD TRAP

    DOEpatents

    Milleron, N.

    1963-03-12

    An improved linear-flow cold trap is designed for highvacuum applications such as mitigating back migration of diffusion pump oil moiecules. A central pot of liquid nitrogen is nested within and supported by a surrounding, vertical, helical coil of metai sheet, all enveloped by a larger, upright, cylindrical, vacuum vessel. The vertical interstices between successive turns of the coil afford lineal, axial, high-vacuum passages between open mouths at top and bottom of said vessel, while the coil, being cold by virtue of thermal contact of its innermost turn with the nitrogen pot, affords expansive proximate condensation surfaces. (AEC)

  13. Measurement of body fat using leg to leg bioimpedance

    PubMed Central

    Sung, R; Lau, P; Yu, C; Lam, P; Nelson, E

    2001-01-01

    AIMS—(1) To validate a leg to leg bioimpedance analysis (BIA) device in the measurement of body composition in children by assessment of its agreement with dual energy x ray absorptiometry (DXA) and its repeatability. (2) To establish a reference range of percentage body fat in Hong Kong Chinese children.
METHODS—Sequential BIA and DXA methods were used to determine body composition in 49 children aged 7-18 years; agreement between the two methods was calculated. Repeatability for the BIA method was established from duplicate measurements. Body composition was then determined by BIA in 1139 girls and 1243 boys aged 7-16 years, who were randomly sampled in eight local primary and secondary schools to establish reference ranges.
RESULTS—The 95% limits of agreement between BIA and DXA methods were considered acceptable (−3.3 kg to −0.5 kg fat mass and −3.9 to 0.6% body fat). The percentage body fat increased with increasing age. Compared to the 1993 Hong Kong growth survey, these children had higher body mass index. Mean (SD) percentage body fat at 7years of age was 17.2% (4.4%) and 14.0% (3.4%) respectively for boys and girls, which increased to 19.3% (4.8%) and 27.8% (6.3%) at age 16.
CONCLUSION—Leg to leg BIA is a valid alternative method to DXA for the measurement of body fat. Provisional reference ranges for percentage body fat for Hong Kong Chinese children aged 7-16 years are provided.

 PMID:11517118

  14. Cell integrated multi-junction thermocouple array for solid oxide fuel cell temperature sensing: N+1 architecture

    NASA Astrophysics Data System (ADS)

    Ranaweera, Manoj; Kim, Jung-Sik

    2016-05-01

    Understanding the cell temperature distribution of solid oxide fuel cell (SOFC) stacks during normal operation has multifaceted advantages in performance and degradation studies. Present efforts on measuring temperature from operating SOFCs measure only the gas channel temperature and do not reveal the cell level temperature distribution, which is more important for understanding a cell's performance and its temperature-related degradation. The authors propose a cell-integrated, multi-junction thermocouple array for in-situ cell surface temperature monitoring of an operational SOFC. The proposed thermocouple array requires far fewer numbers of thermoelements than that required by sets of thermocouples for the same number of temperature sensing points. Hence, the proposed array causes lower disturbance to cell performance than thermocouples. The thermoelement array was sputter deposited on the cathode of a commercial SOFC using alumel (Ni:Al:Mn:Si - 95:2:2:1 by wt.) and chromel (Ni:Cr - 90:10 by wt.). The thermocouple array was tested in a furnace over the entire operating temperature range of a typical SOFC. The individual sensing points of the array were shown to measure temperature independently from each other with equivalent accuracy to a thermocouple. Thus, the concept of multi-junction thermocouples is experimentally validated and its stability on a porous SOFC cathode is confirmed.

  15. Gimbals in the insect leg.

    PubMed

    Frantsevich, Leonid; Wang, Weiying

    2009-01-01

    We studied the common kinematic features of the coxa and trochanter in cursorial and raptorial legs, which are the short size of the podomers, predominantly monoaxial joints, and the approximate orthogonality of adjacent joint axes. The chain coxa-trochanter with its short elements and serial orthogonality of joint axes resembles the gimbals which combine versatility and tolerance to external perturbations. The geometry of legs was studied in 23 insect species of 12 orders. Insects with monoaxial joints were selected. The joint between the trochanter and the femur (TFJ) is defined either by two vestigial condyles or by a straight anterior hinge. Direction of the joint axes in the two basal podomers was assessed by 3D measurements or by goniometry in two planes. Length of the coxa is <15% (mostly <8%) of the total length of the cursorial leg, that of the trochanter <10%. Angles between the proximal and distal joint axes in the middle coxa range from 124 to 84 degrees (mean 97+/-14 degrees ), in the trochanter (in all legs studied) from 125 to 72 degrees (mean 90+/-13 degrees ). Vectors of the distal axis in the coxa are concentrated about the normal to the plane defined by the proximal axis and the midpoint between the distal condyles. These vectors in the trochanter lie at various angles to the normal; angles are correlated with the direction of the TFJ relative to the femur. Range of reduction about the TFJ is over 60 degrees in the foreleg of Ranatra linearis, Mantispa lobata and the hind leg in Carabus coriaceus (confirming observations of previous authors), 40-60 degrees in the foreleg of Vespa crabro and in the middle one in Ammophila campestris, 10-30 degrees in other studied specimens. The special role of the trochanter in autotomy and in active propulsion in some insect groups is discussed. The majority of insects possess small trochanters and slightly movable TFJs with the joint axis laying in the femur-tibia plane. We pose the hypothesis that the TFJ

  16. Cold Sores

    MedlinePlus

    ... causes oral herpes, or cold sores. Type 1 herpes virus infects more than half of the U.S. population by the time they reach their 20s. Type 2 usually affects the genital area Some people have no symptoms from the ...

  17. Method for collecting thermocouple data via secured shell over a wireless local area network in real time.

    PubMed

    Arnold, F; DeMallie, I; Florence, L; Kashinski, D O

    2015-03-01

    This manuscript addresses the design, hardware details, construction, and programming of an apparatus allowing an experimenter to monitor and record high-temperature thermocouple measurements of dynamic systems in real time. The apparatus uses wireless network technology to bridge the gap between a dynamic (moving) sample frame and the static laboratory frame. Our design is a custom solution applied to samples that rotate through large angular displacements where hard-wired and typical slip-ring solutions are not practical because of noise considerations. The apparatus consists of a Raspberry PI mini-Linux computer, an Arduino micro-controller, an Ocean Controls thermocouple multiplexer shield, and k-type thermocouples.

  18. Method for collecting thermocouple data via secured shell over a wireless local area network in real time

    NASA Astrophysics Data System (ADS)

    Arnold, F.; DeMallie, I.; Florence, L.; Kashinski, D. O.

    2015-03-01

    This manuscript addresses the design, hardware details, construction, and programming of an apparatus allowing an experimenter to monitor and record high-temperature thermocouple measurements of dynamic systems in real time. The apparatus uses wireless network technology to bridge the gap between a dynamic (moving) sample frame and the static laboratory frame. Our design is a custom solution applied to samples that rotate through large angular displacements where hard-wired and typical slip-ring solutions are not practical because of noise considerations. The apparatus consists of a Raspberry PI mini-Linux computer, an Arduino micro-controller, an Ocean Controls thermocouple multiplexer shield, and k-type thermocouples.

  19. [Compression therapy in leg ulcers].

    PubMed

    Dissemond, J; Protz, K; Reich-Schupke, S; Stücker, M; Kröger, K

    2016-04-01

    Compression therapy is well-tried treatment with only few side effects for most patients with leg ulcers and/or edema. Despite the very long tradition in German-speaking countries and good evidence for compression therapy in different indications, recent scientific findings indicate that the current situation in Germany is unsatisfactory. Today, compression therapy can be performed with very different materials and systems. In addition to the traditional bandaging with Unna Boot, short-stretch, long-stretch, or multicomponent bandage systems, medical compression ulcer stockings are available. Other very effective but far less common alternatives are velcro wrap systems. When planning compression therapy, it is also important to consider donning devices with the patient. In addition to compression therapy, intermittent pneumatic compression therapy can be used. Through these various treatment options, it is now possible to develop an individually accepted, geared to the needs of the patients, and functional therapy strategy for nearly all patients with leg ulcers.

  20. Relationship of the Cold-Heat Sensation of the Limbs and Abdomen with Physiological Biomarkers

    PubMed Central

    Lee, JeongHoon; Kim, GaYul; Song, JiYeon

    2016-01-01

    The present study explored the relationship between the regional Cold-Heat sensation, the key indicator of the Cold-Heat patterns in traditional East Asian medicine (TEAM), and various biomarkers in Korean population. 734 apparently healthy volunteers aged 20 years and older were enrolled. Three scale self-report questions on the general thermal feel in hands, legs, and abdomen were examined. We found that 65% of women tended to perceive their body, particularly their hands and legs, to be cold, versus 25% of men. Energy expenditure and temperature load at resting state were lower in women, independently of body mass index (BMI). Those with warm hands and warm legs had a 0.74 and 0.52 kg/m2 higher BMI than those with cold hands and cold legs, respectively, regardless of age, gender, and body weight. Norepinephrine was higher, whereas the dynamic changes in glucose and insulin during an oral glucose tolerance test were lower in those with cold extremities, particularly hands. No consistent differences in biomarkers were found for the abdominal dimension. These results suggest that gender, BMI, the sympathetic nervous system, and glucose metabolism are potential determinants of the Cold-Heat sensation in the hands and legs, but not the abdomen. PMID:27818698

  1. Attachment of Free Filament Thermocouples for Temperature Measurements on Ceramic Matrix Composites

    NASA Technical Reports Server (NTRS)

    Lei, Jih-Fen; Cuy, Michael D.; Wnuk, Stephen P.

    1998-01-01

    At the NASA Lewis Research Center, a new installation technique utilizing convoluted wire thermocouples (TC's) was developed and proven to produce very good adhesion on CMC's, even in a burner rig environment. Because of their unique convoluted design, such TC's of various types and sizes adhere to flat or curved CMC specimens with no sign of delamination, open circuits, or interactions-even after testing in a Mach 0.3 burner rig to 1200 C (2200 F) for several thermal cycles and at several hours at high temperatures. Large differences in thermal expansion between metal thermocouples and low-expansion materials, such as CMC's, normally generate large stresses in the wires. These stresses cause straight wires to detach, but convoluted wires that are bonded with strips of coating allow bending in the unbonded portion to relieve these expansion stresses.

  2. Assignment of Temperature to a Vertical Co-C Cell for Thermocouple Calibration

    NASA Astrophysics Data System (ADS)

    García Izquierdo, C.; Martín, M. J.; Mantilla, J. M.; del Campo, D.

    2015-03-01

    Noble metal thermocouples are often required to be calibrated up to in fixed points in order to get the lowest uncertainties. The International Temperature Scale of 1990 (ITS-90) defines the temperature of fixed points until the copper point (). At higher temperatures, the metal carbon fixed points can be used, and the needed traceability to the ITS-90 is given by means of a standard radiation thermometer. This paper presents the method developed by the Centro Español de Metrologia to give traceability to the ITS-90 to the Co-C cell used to calibrate thermocouples by means of a mirror and a standard radiation thermometer with an expanded uncertainty () of.

  3. Hot, Cold, and Really Cold.

    ERIC Educational Resources Information Center

    Leyden, Michael

    1997-01-01

    Describes a physics experiment investigating temperature prediction and the relationship between the physical properties of heat units, melting, dissolving, states of matter, and energy loss. Details the experimental setup, which requires hot and cold water, a thermometer, and ice. Notes that the experiment employs a deliberate counter-intuitive…

  4. Sheathed thermocouples for continuous molten steel temperature measurement during the ladle treatment process

    SciTech Connect

    Phillippi, R.M. . Accumetrix Div.)

    1989-09-01

    The evolution of a thermocouple protection sheath for use in liquid steel during the ladle treatment process is described. Five different designs constructed of boron nitride, alumina-graphite, and magnesia-graphite were evaluated. Results show that excellent slag wear characteristics are possible using magnesia-graphite but improvements in thermal shock resistance and response time are required. Temperature profiles during argon stirring, addition of chill scrap, and natural cooling are presented. 3 refs., 19 figs.

  5. Bed inventory overturn in a circulating fluid bed riser with pant-leg structure

    SciTech Connect

    Jinjing Li; Wei Wang; Hairui Yang; Junfu Lv; Guangxi Yue

    2009-05-15

    The special phenomenon, nominated as bed inventory overturn, in circulating fluid bed (CFB) riser with pant-leg structure was studied with model calculation and experimental work. A compounded pressure drop mathematic model was developed and validated with the experimental data in a cold experimental test rig. The model calculation results agree well with the measured data. In addition, the intensity of bed inventory overturn is directly proportional to the fluidizing velocity and is inversely proportional to the branch point height. The results in the present study provide significant information for the design and operation of a CFB boiler with pant-leg structure. 15 refs., 10 figs., 1 tab.

  6. Application of Thin-Film Thermocouples to Localized Heat Transfer Measurements

    NASA Technical Reports Server (NTRS)

    Lepicovsky, J.; Bruckner, R. J.; Smith, F. A.

    1995-01-01

    The paper describes a proof-of-concept experiment on thin-film thermocouples used for localized heat transfer measurements applicable to experiments on hot parts of turbine engines. The paper has three main parts. The first part describes the thin-film sensors and manufacturing procedures. Attention is paid to connections between thin-film thermocouples and lead wires, which has been a source of problems in the past. The second part addresses the test arrangement and facility used for the heat transfer measurements modeling the conditions for upcoming warm turbine tests at NASA LeRC. The paper stresses the advantages of a modular approach to the test rig design. Finally, we present the results of bulk and local heat flow rate measurements, as well as overall heat transfer coefficients obtained from measurements in a narrow passage with an aspect ratio of 11.8. The comparison of bulk and local heat flow rates confirms applicability of thin-film thermocouples to upcoming warm turbine tests.

  7. Validation of a Blackbody Comparator-Based System for Thermocouple Calibration

    NASA Astrophysics Data System (ADS)

    Ojanen, M.; Hahtela, O.; Heinonen, M.

    2014-04-01

    A blackbody comparator for thermocouple calibration in the temperature range from to has previously been developed at the Centre for Metrology and Accreditation (MIKES). The calibration system is based on direct comparison of thermocouples and a radiation thermometer. In this article, the blackbody comparator is exploited by comparing an absolute calibrated irradiance mode filter radiometer and a linear pyrometer calibrated according to the International Temperature Scale of 1990 (ITS-90) to each other in the temperature range from to . The results of the comparison are in agreement within uncertainties (). Furthermore, thermal gradients in the blackbody comparator are studied by means of numerical simulation, as the gradients were found to be the major source of uncertainty in previous work. A thermal model was constructed with COMSOL software, and the radial and longitudinal gradients were studied in the comparator. The results of the modeling are in agreement with the uncertainty determination carried out in previous work, but the gradients still remain a significant uncertainty contribution. The validation of the calibration system was completed by comparing calibration results obtained with the system for a Pt/Pd thermocouple to calibration results reported by the National Physical Laboratory (NPL), UK. The results of the comparison agree within the expanded uncertainty () of the comparison.

  8. Relating Composition and Thermoelectric Stability of Pt-Rh Alloy Thermocouples

    NASA Astrophysics Data System (ADS)

    Pearce, J. V.; Greenen, A. D.; Smith, A.; Elliott, C. J.

    2017-02-01

    A simple model is presented which relates the electromotive force drift rate of Pt-Rh thermoelements to dS/dc, the sensitivity of the Seebeck coefficient, S, to rhodium mass fraction, c. The model has been tested by repeated measurements of a Pt-Rh thermocouple assembly consisting of five thermoelements, using a Co-C high-temperature fixed point (1324°C) for a total duration of 500 h. By considering various thermocouples from the assembly, it is demonstrated that in this case, remarkably, there is a linear relationship between the measured drift rate and the combined dS/dc, where the combination is determined by addition of the individual values for each wire. Particular emphasis is placed on evaluation of the uncertainties associated with the calculations. This result supports previous findings that the thermoelectric stability of Pt-Rh thermoelements improves as the rhodium mass fraction increases. Within this paradigm, it is shown that for a selected Pt-Rh thermoelement of any given composition, there exists a second thermoelement having a composition that yields a minimum drift when combined with the first to form a thermocouple.

  9. A Quantitative Model for the Thermocouple Effect Using Statistical and Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Bramley, Paul; Clark, Stewart

    2003-09-01

    This paper employs statistical and quantum mechanics to develop a model for the mechanism underlying the Seebeck effect. The conventional view of the equilibrium criterion for valence electrons in a material is that the Fermi Energy should be constant throughout the system. However, this criterion is an approximation and it is shown to be inadequate for thermocouple systems. An improved equilibrium criterion is developed by applying statistical and quantum mechanics to determine the total flow of electrons across an arbitrary boundary within a system. Dynamic equilibrium is then considered to be the situation where the Fermi Energy either side of the boundary is such that the flow of electrons in each direction is the same. This equilibrium criterion is then applied to the conditions along the thermocouple wires and at the junctions in order to generate a model for the Seebeck effect. The equations involved for calculating the electronic structure of a material cannot be solved analytically, so a solution is achieved using numeric models employing CASTEP code running on a Sun Beowulf cluster and iterative algorithms written in the Excel™ VBA language on a PC. The model is used to calculate the EMF versus temperature function for the gold versus platinum thermocouple, which is then compared with established experimental data.

  10. A Multi-Point Measurement Method for Thermal Characterization of Foil Bearings Using Customized Thermocouples

    NASA Astrophysics Data System (ADS)

    Lubieniecki, Michał; Roemer, Jakub; Martowicz, Adam; Wojciechowski, Krzysztof; Uhl, Tadeusz

    2016-03-01

    Gas foil bearings have become widespread covering the applications of micro-turbines, motors, compressors, and turbocharges, prevalently of small size. The specific construction of the bearing, despite all of its advantages, makes it vulnerable to a local difference in heat generation rates that can be extremely detrimental. The developing thermal gradients may lead to thermal runaway or seizure that eventually causes bearing failure, usually abrupt in nature. The authors propose a method for thermal gradient removal with the use of current-controlled thermoelectric modules. To fulfill the task of control law adoption the numerical model of the heat distribution in a bearing has been built. Although sparse readings obtained experimentally with standard thermocouples are enough to determine thermal gradients successfully, validation of the bearing numerical model may be impeded. To improve spatial resolution of the experimental measurements the authors proposed a matrix of customized thermocouples located on the top foil. The foil acts as a shared conductor for each thermocouple that reduces the number of cable connections. The proof of concept of the control and measurement systems has been demonstrated in a still bearing heated by a cartridge heater.

  11. Cold Stress and Urinary Frequency.

    PubMed

    Ishizuka, Osamu; Imamura, Tetsuya; Nishizawa, Osamu

    2012-03-01

    There have been few studies regarding the onset of urinary sensations and frequent urination induced by sudden whole-body cooling. In this article, we review the relationship between cold stress and urinary frequency based mainly on our previous studies. A recent study showed that cold stress induces bladder overactivity in conscious rats, and these effects were mediated, at least in part, by α1A -adrenergic receptor (AR) and α1D -AR. Another study suggested that the resiniferatoxin-sensitive nerves present in the urinary bladder may also be involved in the regulation of detrusor activity associated with cold stress. The mammalian transient receptor potential (TRP) channel family consists of 28 channels subdivided into five different classes: TRPV (vanilloid), TRPC (canonical), TRPM (melastatin), TRPML (mucolipin), and TRPA (ankyrin). TRP channels function as multifunctional sensors at the cellular level. They can be activated by physical (voltage, heat, cold, mechanical stress) or chemical stimuli and binding of specific ligands. In 2002, it was reported that a nonselective cation channel, TRPM8, could be activated by both menthol and thermal stimuli (8-28 °C). We demonstrated the presence of TRPM8 in the skin from the legs and back of rats by immunofluorescence staining and that stimulation of this receptor by menthol causes urinary frequency. There have been other reports demonstrating roles of TRPM8 not related to its thermosensory function. Further studies are needed to clarify the mechanism of cold stress-induced urinary frequency, and the roles of TRPM8 in the micturition control system.

  12. Tool Blunts Cotter Pin Legs for Safety

    NASA Technical Reports Server (NTRS)

    Stein, J. A.; Helble, D. R.

    1982-01-01

    Jaws on new insertion tool contain upset point and anvil. Point forces cotter-pin legs into loop as it engages anvil. Cotter pin before insertion consists of loop and straight shaft composed of two legs welded together as tips. After insertion, welded legs have been shaped into loop. Tool used to prevent bent loose ends of cotter pins from scratching workers' fingers or cutting and entangling wires.

  13. COLD TRAPS

    DOEpatents

    Thompson, W.I.

    1958-09-30

    A cold trap is presented for removing a condensable component from a gas mixture by cooling. It consists of a shell, the exterior surface of which is chilled by a refrigerant, and conductive fins welded inside the shell to condense the gas, and distribute the condensate evenly throughout the length of the trap, so that the trap may function until it becomes completely filled with the condensed solid. The contents may then be removed as either a gas or as a liquid by heating the trap. This device has particuinr use as a means for removing uranium hexafluoride from the gaseous diffusion separation process during equipment breakdown and repair periods.

  14. Radiation of anginal pain to the legs.

    PubMed Central

    Kolettis, M T; Kalogeropoulos, C K; Tzannetis, G C; Vitakis, S K; Xaplanteris, P P; Novas, I A

    1986-01-01

    Pain radiated from the chest to one or both legs (17 cases), or from the legs to the chest (two cases) in 19 patients with angina or acute myocardial infarction. The leg pain was assumed to be related to the angina pectoris when both were of a similar character and occurred together, when the leg pain occurred at rest, and when there were normal peripheral pulses in the leg. Pain was felt in the left leg by 10 patients, the right leg by two patients, and in both legs by seven. Three patients experienced pain in the thigh(s), six in the shin(s), and 10 had pain in both. In six patients the pain extended down to the inner two to four toes. The pain was always felt in front of the legs. This distribution accords with the suggestion that some sensory cardiac nerve fibres occur in the lumbar sympathetic ganglia and that pain is projected into the corresponding dermatomes. PMID:3942655

  15. Space Elevator Base Leg Architecture

    NASA Astrophysics Data System (ADS)

    Swan, C.; Swan, P. A.

    While the Space Elevator stretches for 104,000 kilometers, the region of most concern, from the survival perspective, is 2,500 kms and below. The threats inside this dangerous arena include debris, spacecraft, meteorites, lightening, winds, rogue waves, aircraft, and intentional human acts. Two major questions will be addressed that will influence the overall systems architecture of a Space Elevator. While the deployment phase of the development of the Space Elevator will only have a single ribbon from the surface of the Earth to well beyond the Geosynchronous altitude, a mature Space Elevator must never allow a complete sever of the system. Design approaches, materials selections, international policy development and assembly must ensure that the integrity of the Space Elevator be maintained. The trade space analysis will address the probability of an individual ribbon being severed, the length of time to repair, and the potential for a catastrophic Space Elevator cut. The architecture proposed for the base leg portion will address two questions: Shall there be multiple base legs to 2,500 kms altitude? And Should the anchor be based on land or at sea?

  16. Leg automaticity is stronger than arm automaticity during simultaneous arm and leg cycling.

    PubMed

    Sakamoto, Masanori; Tazoe, Toshiki; Nakajima, Tsuyoshi; Endoh, Takashi; Komiyama, Tomoyoshi

    2014-04-03

    Recent studies indicate that human locomotion is quadrupedal in nature. An automatic rhythm-generating system is thought to play a crucial role in controlling arm and leg movements. In the present study, we attempted to elucidate differences between intrinsic arm and leg automaticity by investigating cadence variability during simultaneous arm and leg (AL) cycling. Participants performed AL cycling with visual feedback of arm or leg cadence. Participants were asked to focus their attention to match the predetermined cadence; this affects the automaticity of the rhythm-generating system. Leg cadence variability was only mildly affected when the participants intended to precisely adjust either their arm or leg cycling cadence to a predetermined value. In contrast, arm cadence variability significantly increased when the participants adjusted their leg cycling cadence to a predetermined value. These findings suggest that different neural mechanisms underlie the automaticities of arm and leg cycling and that the latter is stronger than the former during AL cycling.

  17. Cold Urticaria

    PubMed Central

    Wasserman, Stephen I.; Soter, Nicholas A.; Center, David M.; Austen, K. Frank

    1977-01-01

    Sera were obtained from the venous effluents of cold-challenged arms of patients with idiopathic cold urticaria without plasma or serum cryoproteins; these sera exhibited increased neutrophil chemotactic activity without alterations of the complement system. A two- to fourfold augmentation of the base-line neutrophil chemotactic activity of serum from the immersed extremity began within 1 min, peaked at 2 min, and returned to base-line levels within 15 min, whereas there was no change in the serum chemotactic activity in the control arm. The augmented chemotactic activity in the serum specimens from the challenged arm of each patient appeared in a high molecular-weight region, as assessed by the difference in activity recovered after Sephadex G-200 gel filtration of the paired lesional and control specimens. Sequential purification of this high molecular-weight activity by anion- and cation-exchange chromatography revealed a single peak of activity at both steps. The partially purified material continued to exhibit a high molecular weight, being excluded on Sepharose 4B, and had a neutral isoelectric point. The partially purified material showed a preferential chemotactic activity for neutrophilic polymorphonuclear leukocytes, required a gradient for expression of this function, and exhibited a capacity to deactivate this cell type. This active principle, termed high molecular-weight neutrophil chemotactic factor, exhibited a time-course of release that could be superimposed upon that of histamine and the low molecular-weight eosinophil chemotactic factor and may represent another mast cell-derived mediator. PMID:874083

  18. The Relationship among Leg Strength, Leg Power and Alpine Skiing Success.

    ERIC Educational Resources Information Center

    Gettman, Larry R.; Huckel, Jack R.

    The purpose of this study was to relate leg strength and power to alpine skiing success as measured by FIS points. Isometric leg strength was represented by the knee extension test described by Clarke. Leg power was measured by the vertical jump test and the Margaria-Kalamen stair run. Results in the strength and power tests were correlated with…

  19. Restless legs syndrome mimicking S1 radiculopathy.

    PubMed

    Zambelis, Th; Wolgamuth, B R; Papoutsi, S N; Economou, N T

    2016-01-01

    Α case of a chronic idiopathic form of a severe type of Restless Legs Syndrome (RLS), which developed during pregnancy and persisted after this, misdiagnosed for 34 years as radiculopathy S1, is reported. In spite of the thorough clinical and laboratory investigation, in addition to constant changes of the therapeutic approach, the diagnosis of S1 radiculopathy could not be confirmed, resulting in a chronic clinical course; the latter was characterized by relapses and remissions not attributed or linked in any way to the treatment (various types of). In fact, it was due to a routine workup in a sleep clinic, where the patient was referred because of a coincident chronic insomnia (Restless Legs Syndrome is a known and important cause of insomnia/chronic insomnia), which resulted in a proper diagnosis and treatment of this case. With the use of Restless Legs Syndrome appropriate treatment (Pramipexole 0.18 mg taken at bedtime, a dopaminergic agent and Level A recommended drug for Restless Legs Syndrome) an excellent response and immediate elimination of symptoms was achieved. Restless Legs Syndrome may present with a variety of symptoms (with the most prominent shortly being reported with the acronym URGE: Urge to move the legs usually associated with unpleasant leg sensations, Rest induces symptoms, Getting active brings relief, Evening and night deteriorate symptoms); given the fact that Restless Legs Syndrome presents with a great variety and heterogeneity of symptoms (mostly pain, dysesthesia and paresthesia), which may occur in several other diseases (the so called "RLS mimics"), proper diagnosis of Restless Legs Syndrome usually fails. Restless Legs Syndrome misinterpreted as S1 radiculopathy, to the best of our knowledge, has not been reported yet in the literature. Here, case history, clinical course and common RLS mimics are presented. Different forms of Restless Legs Syndrome manifestations, which are commonly -as in this case- misinterpreted due to their

  20. Simple method for measuring vibration amplitude of high power airborne ultrasonic transducer: using thermo-couple.

    PubMed

    Saffar, Saber; Abdullah, Amir

    2014-03-01

    Vibration amplitude of transducer's elements is the influential parameters in the performance of high power airborne ultrasonic transducers to control the optimum vibration without material yielding. The vibration amplitude of elements of provided high power airborne transducer was determined by measuring temperature of the provided high power airborne transducer transducer's elements. The results showed that simple thermocouples can be used both to measure the vibration amplitude of transducer's element and an indicator to power transmission to the air. To verify our approach, the power transmission to the air has been investigated by other common method experimentally. The experimental results displayed good agreement with presented approach.

  1. X-Ray Exam: Femur (Upper Leg)

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Femur (Upper Leg) KidsHealth > For Parents > X-Ray Exam: Femur (Upper Leg) Print A A A ... español Radiografía: fémur What It Is A femur X-ray is a safe and painless test that uses ...

  2. Why do flamingos stand on one leg?

    PubMed

    Anderson, Matthew J; Williams, Sarah A

    2010-01-01

    A series of observational studies of captive Caribbean flamingos Phoenicopterus ruber were conducted to determine why flamingos rest on one leg. While frequently asked by the general public, this basic question has remained unanswered by the scientific community. Here we suggest that the latency of flamingos to initiate forward locomotion following resting on one leg is significantly longer than following resting on two, discounting the possibility that unipedal resting reduces muscle fatigue or enhances predatory escape. Additionally, we demonstrate that flamingos do not display lateral preferences at the individual or group levels when resting on one leg, with each bird dividing its resting time across both legs. We show that while flamingos prefer resting on one leg to two regardless of location, the percentage of birds resting on one leg is significantly higher among birds standing in the water than among those on land. Finally, we demonstrate a negative relationship between temperature and the percentage of observed birds resting on one leg, such that resting on one leg decreases as temperature rises. Results strongly suggest that unipedal resting aids flamingos in thermoregulation.

  3. Restless Legs Syndrome -- Causes and Symptoms

    MedlinePlus

    ... of restless legs syndrome varies from person to person. In some cases the cause is unknown, or it can be caused by or made worse by other health issues or medication. This may include: Low iron levels This can cause problems with brain cell communication that can lead to restless legs syndrome. ...

  4. Genetics Home Reference: restless legs syndrome

    MedlinePlus

    ... T, Wichmann HE, Müller-Myhsok B, Meitinger T. Genome-wide association study identifies novel restless legs syndrome susceptibility loci on ... HE, Holsboer F, Müller-Myhsok B, Meitinger T. Genome-wide association study of restless legs syndrome identifies common variants in ...

  5. A Hydroxyurea-induced Leg Ulcer

    PubMed Central

    Hwang, Seon-Wook; Hong, Soon-Kwon; Kim, Sang-Hyun; Seo, Jong-Keun; Sung, Ho-Suk

    2009-01-01

    Hydroxyurea is a cytostatic agent that has recently become the drug of choice in the treatment of various myeloproliferative diseases. The cutaneous side effects of hydroxyurea include xerosis, hyperpigmentation, nail discoloration, and scaling. Leg ulcers have only rarely been reported in association with hydroxyurea treatment. A 75-year-old woman presented with leg ulcers, nail discoloration, and xerosis. The leg ulcers were refractory to conventional treatment. She had been taking oral hydroxyurea since being diagnosed with essential thrombocytosis in 2002. Hence, we suspected hydroxyurea-induced leg ulcers and discontinued her hydroxyurea treatment; the ulcers gradually healed thereafter. We present a rare case of hydroxyurea-induced leg ulcers in Korea. PMID:20548853

  6. Drug-induced restless legs syndrome.

    PubMed

    2010-08-01

    Restless legs syndrome can be very troublesome but it has no serious physical complications. The underlying causes are unknown, but it can be triggered or aggravated by a drug. In early 2010, about 60 cases of drug-induced restless legs syndrome had been published in detail. The drugs implicated were mainly psychotropics, especially antidepressants and neuroleptics. Some drugs used to treat restless legs syndrome, especially dopaminergic drugs, can in fact aggravate symptoms. Drug-induced restless legs syndrome generally resolves when the dose is reduced or the drug is withdrawn. Dysfunction of the dopaminergic system has been implicated in some cases. In practice, when a patient presents with restless legs syndrome, the role of a drug, especially a psychotropic, should be considered. Drug withdrawal or a dose reduction may be beneficial.

  7. Thermocouple Positioning For The Application Of The Non-Integer System Identification Approach To HIFIRE-5 Fins

    NASA Astrophysics Data System (ADS)

    Lohle, Stefan; Bohrk, Hannah; Fuchs, Ulf

    2011-05-01

    The German Aerospace Center developed a ceramic fin experiment (FinEx) for HIFiRE-5 flight in order to test the performance of new structure designs during hyper- sonic flight. Aero-thermal analysis is provided by 8 thermocouple data channels for all four symmetrically arranged fins. In this paper the analysis of the geometry and thermophysical characteristics of the fins to optimize thermocouple positioning is discussed. The main goal is to gather as much information as possible from these few temperature sensors in these three dimensional structures. Not only is the absolute temperature value of interest but also the reason of the temperature rise. A thorough calculation of the temperature gradients in the fin structure is used to define an optimal positioning layout, where particular focus lies on the localization of the heat fluxes at the surface from the in-depth thermocouple measurement. In conclusion, two fins are equipped with 3 thermocouples each and two are equipped with only 1 thermocouple. The paper closes with some first results based on the calibration data of the fins and the nominal trajectory values.

  8. Cough & Cold Medicine Abuse

    MedlinePlus

    ... Loss Surgery? A Week of Healthy Breakfasts Shyness Cough & Cold Medicine Abuse KidsHealth > For Teens > Cough & Cold ... Someone Quit? Avoiding DXM Why Do People Use Cough and Cold Medicines to Get High? There's an ...

  9. Acceptance test report for tank bottom thermocouples on Tank 241-SY-101

    SciTech Connect

    Zuehlke, A.C.

    1994-12-01

    This test report documents testing performed per WHC-SD-WM-ATP-069, Rev. 2. The proper monitoring of the 241-SY-101 Tank Bottom and Side Thermocouples (TBSTC) by the Data Acquisition and Control System (DACS) will be tested to establish continued operability of the system. During this test, an end-to-end verification of all of the sensor circuits associated with the TBSTCs, which provide signals both to the DACS computer system and an installed temporary Data Logger, shall be performed by injecting a signal at the appropriate field terminal and verifying the circuit completely through the system to the computer in the DACS trailer and the computer monitor used to display the output of the Data Logger. Each injected signal will be adjusted for appropriate `near zero`, `mid range` and `near full scale` values for the sensor being tested. The TBSTC screen, which provides for operator interface with the TBSTCs, will be utilized to monitor testing at the DACS computers. Testing per this procedure shall be conducted after the installation of the temporary Data Logger for the TBSTCs is complete. The temporary Data Logger will be installed to monitor the temperature readings of 13 of the 26 Tank Bottom Thermocouples in support of SY-101 excavation testing.

  10. High temperature blackbody BB2000/40 for calibration of radiation thermometers and thermocouple

    SciTech Connect

    Ogarev, S. A.; Khlevnoy, B. B.; Samoylov, M. L.; Puzanov, A. V.

    2013-09-11

    The cavity-type high temperature blackbody (HTBB) models of BB3200/3500 series are the most spread among metrological institutes worldwide as sources for radiometry and radiation thermometry, due to their ultra high working temperatures, high emissivity and stability. The materials of radiating cavities are graphite, pyrolytic graphite (PG) and their combination. The paper describes BB2000/40 blackbody with graphite-tube cavity that was developed for calibration of radiation thermometers at SCEI (Singapore). The peculiarity of BB2000/40 is a possibility to use it, besides calibration of pyrometers, as an instrument for thermocouples calibration. Operating within the temperature range from 900 °C to 2000 °C, the blackbody has a wide cavity opening of 40 mm. Emissivity of the cavity, with PG heater rings replaced partly by graphite elements, was estimated as 0.998 ± 0.0015 in the spectral range from 350 nm to 2000 nm. The uniformity along the cavity axis, accounting for 10 °C, was measured using a B-type thermocouple at 1500 °C. The BB2000/40, if necessary, can be easily modified, by replacing the graphite radiator with a set of PG rings, to be able to reach temperatures as high as 3200 °C. The HTBB utilizes an optical feedback system which allows temperature stabilization within 0.1 °C. This rear-view feedback allows the whole HTBB aperture to be used for measurements.

  11. Anodic vacuum arc developed nanocrystalline Cu-Ni and Fe-Ni thin film thermocouples

    SciTech Connect

    Mukherjee, S. K.; Sinha, M. K.; Pathak, B.; Rout, S. K.; Barhai, P. K.

    2009-12-01

    This paper deals with the development of nanocrystalline Cu-Ni and Fe-Ni thin film thermocouples (TFTCs) by using ion-assisted anodic vacuum arc deposition technique. The crystallographic structure and surface morphology of individual layer films have been studied by x-ray diffraction and scanning electron microscopy, respectively. The resistivity, temperature coefficient of resistance, and thermoelectric power of as deposited and annealed films have been measured. The observed departure of these transport parameters from their respective bulk values can be understood in terms of intrinsic scattering due to enhanced crystallite boundaries. From the measured values of thermoelectric power and the corresponding temperature coefficient of resistance of annealed Cu, Ni, and Fe films, the calculated values of log derivative of the mean free path of conduction electrons at the Fermi surface with respect to energy (U) are found to be -0.51, 3.22, and -8.39, respectively. The thermoelectric response of annealed Cu-Ni and Fe-Ni TFTCs has been studied up to a maximum temperature difference of 300 deg. C. Reproducibility of TFTCs has been examined in terms of the standard deviation in thermoelectric response of 16 test samples for each pair. Cu-Ni and Fe-Ni TFTCs agree well with their wire thermocouple equivalents. The thermoelectric power values of Cu-Ni and Fe-Ni TFTCs at 300 deg. C are found to be 0.0178 and 0.0279 mV/ deg. C, respectively.

  12. Advances in Thin Film Thermocouple Durability Under High Temperature and Pressure Testing Conditions

    NASA Technical Reports Server (NTRS)

    Martin, Lisa C.; Fralick, Gustave C.; Taylor, Keith F.

    1999-01-01

    Thin film thermocouples for measuring material surface temperature have been previously demonstrated on several material systems and in various hostile test environments. A well-developed thin film fabrication procedure utilizing shadow masking for patterning the sensors elements had produced thin films with sufficient durability for applications in high temperature and pressure environments that exist in air-breathing and hydrogen-fueled burner rig and engine test facilities. However, while shadow masking had been a reliable method for specimens with flat and gently curved surfaces, it had not been consistently reliable for use on test components with sharp contours. This work reports on the feasibility of utilizing photolithography processing for patterning thin film thermocouples. Because this patterning process required changes in the thin film deposition process from that developed for shadow masking, the effect of these changes on thin film adherence during burner rig testing was evaluated. In addition to the results of changing the patterning method, the effects on thin film adherence of other processes used in the thin film fabrication procedure is also presented.

  13. Anodic vacuum arc developed nanocrystalline Cu-Ni and Fe-Ni thin film thermocouples

    NASA Astrophysics Data System (ADS)

    Mukherjee, S. K.; Sinha, M. K.; Pathak, B.; Rout, S. K.; Barhai, P. K.

    2009-12-01

    This paper deals with the development of nanocrystalline Cu-Ni and Fe-Ni thin film thermocouples (TFTCs) by using ion-assisted anodic vacuum arc deposition technique. The crystallographic structure and surface morphology of individual layer films have been studied by x-ray diffraction and scanning electron microscopy, respectively. The resistivity, temperature coefficient of resistance, and thermoelectric power of as deposited and annealed films have been measured. The observed departure of these transport parameters from their respective bulk values can be understood in terms of intrinsic scattering due to enhanced crystallite boundaries. From the measured values of thermoelectric power and the corresponding temperature coefficient of resistance of annealed Cu, Ni, and Fe films, the calculated values of log derivative of the mean free path of conduction electrons at the Fermi surface with respect to energy (U) are found to be -0.51, 3.22, and -8.39, respectively. The thermoelectric response of annealed Cu-Ni and Fe-Ni TFTCs has been studied up to a maximum temperature difference of 300°C. Reproducibility of TFTCs has been examined in terms of the standard deviation in thermoelectric response of 16 test samples for each pair. Cu-Ni and Fe-Ni TFTCs agree well with their wire thermocouple equivalents. The thermoelectric power values of Cu-Ni and Fe-Ni TFTCs at 300°C are found to be 0.0178 and 0.0279mV/°C, respectively.

  14. Steerable Hopping Six-Legged Robot

    NASA Technical Reports Server (NTRS)

    Younse, Paulo; Aghazarian, Hrand

    2010-01-01

    The figure depicts selected aspects of a six-legged robot that moves by hopping and that can be steered in the sense that it can be launched into a hop in a controllable direction. This is a prototype of hopping robots being developed for use in scientific exploration of rough terrain on remote planets that have surface gravitation less than that of Earth. Hopping robots could also be used on Earth, albeit at diminished hopping distances associated with the greater Earth gravitation. The upper end of each leg is connected through two universal joints to an upper and a lower hexagonal frame, such that the tilt of the leg depends on the relative position of the two frames. Two non-back-driveable worm-gear motor drives are used to control the relative position of the two frames along two axes 120 apart, thereby controlling the common tilt of all six legs and thereby, further, controlling the direction of hopping. Each leg includes an upper and a lower aluminum frame segment with a joint between them. A fiberglass spring, connected via hinges to both segments, is used to store hopping energy prior to launch into a hop and to cushion the landing at the end of the hop. A cable for loading the spring is run into each leg through the center of the universal joints and then down along the center lines of the segments to the lower end of the leg. A central spool actuated by a motor with a harmonic drive and an electromagnetic clutch winds in all six cables to compress all six springs (thereby also flexing all six legs) simultaneously. To ensure that all the legs push off and land in the same direction, timing- belt pulley drives are attached to the leg segments, restricting the flexing and extension of all six legs to a common linear motion. In preparation for a hop, the spool can be driven to load the spring legs by an amount corresponding to a desired hop distance within range. The amount of compression can be computed from the reading of a shaft-angle encoder that

  15. A fine-wire thermocouple probe for measurement of stagnation temperatures in real gas hypersonic flows of nitrogen

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Griffith, Wayland C.; Yanta, William J.

    1991-01-01

    A fine-wire thermocouple probe was used to determine freestream stagnation temperatures in hypersonic flows. Data were gathered in a N2 blowdown wind tunnel with runtimes of 1-5 s. Tests were made at supply pressures between 30 and 1400 atm and supply temperatures between 700 and 1900 K, with Mach numbers of 14 to 16. An iterative procedure requiring thermocouple data, pilot pressure measurements, and supply conditions was used to determine test cell stagnation temperatures. Probe conduction and radiation losses, as well as real gas behavior of N2, were accounted for during analysis. Temperature measurement error was found to be 5 to 10 percent. A correlation was drawn between thermocouple diameter Reynolds number and temperature recovery ratio. Transient probe behavior was studied and was found to be adequate in temperature gradients up to 1000 K/s.

  16. Cold confusion

    SciTech Connect

    Chapline, G.

    1989-07-01

    On March 23 two chemists, Martin Fleischmann and Stanley Pons startled the world with a press conference at the University of Utah where they announced that they had achieved nuclear fusion at room temperatures. As evidence they cited the production of ''excess'' amounts of heat in an electrochemical apparatus and observation of neutron production. While the production of heat in a chemical apparatus is not in itself unusual the observation of neutrons is certainly extraordinary. As it turned out, though, careful measurements of the neutron production in electrochemical apparatus similar to that used by Fleischmann and Pons carried out at dozens of other laboratories has shown that the neutron production fails by many orders of magnitude to support the assertion by Fleischmann and Pons that their discovery represents a new and cheap source of fusion power. In particular, independent measurements of the neutron production rate suggest that the actual rate of fusion energy production probably does not exceed 1 trillionth of a watt. This paper discusses the feasibility that cold fusion is actually being achieved. 7 refs.

  17. Differences and correlations in knee and hip mechanics during single-leg landing, single-leg squat, double-leg landing, and double-leg squat tasks.

    PubMed

    Donohue, Michael R; Ellis, Samantha M; Heinbaugh, Erika M; Stephenson, Mitchell L; Zhu, Qin; Dai, Boyi

    2015-01-01

    Landing and squat tasks have been utilized to assess lower extremity biomechanics associated with anterior cruciate ligament loading and injury risks. The purpose of this study was to identify the differences and correlations in knee and hip mechanics during a single-leg landing, a single-leg squat, a double-leg landing, and a double-leg squat. Seventeen male and 17 female recreational athletes performed landings and squats when kinematic and kinetic data were collected. ANOVAs showed significant differences (p < 0.00001) for maximum knee flexion angles, maximum hip flexion angles, maximum knee abduction angles, maximum hip adduction angles, and maximum external knee abduction moments among squats and landings. For maximum knee and hip flexion angles, significant correlations (r ≥ 0.5, p ≤ 0.003) were observed between the two landings and between the two squats. For maximum knee abduction and hip adduction angles and maximum external knee abduction moments, significant correlations were mostly found between the two landings, and between the single-leg squat and landings (r ≥ 0.54, p ≤ 0.001). Individuals are likely to demonstrate different profiles of injury risks when screened using different tasks. While a double-leg landing should be considered as a priority in screening, a single-leg squat may be used as a surrogate to assess frontal plane motion and loading.

  18. Expansion Compression Contacts for Thermoelectric Legs

    NASA Technical Reports Server (NTRS)

    Sakamoto, Jeffrey

    2009-01-01

    In a proposed alternative to previous approaches to making hot-shoe contacts to the legs of thermoelectric devices, one relies on differential thermal expansion to increase contact pressures for the purpose of reducing the electrical resistances of contacts as temperatures increase. The proposed approach is particularly applicable to thermoelectric devices containing p-type (positive-charge-carrier) legs made of a Zintl compound (specifically, Yb14MnSb11) and n-type (negative charge-carrier) legs made of SiGe. This combination of thermoelectric materials has been selected for further development, primarily on the basis of projected thermoelectric performance. However, it is problematic to integrate, into a practical thermoelectric device, legs made of these materials along with a metal or semiconductor hot shoe that is required to be in thermal and electrical contact with the legs. This is partly because of the thermal-expansion mismatch of these materials: The coefficient of thermal expansion (CTE) of SiGe is 4.5 x 10(exp -6) C (exp -1), while the CTE of Yb14MnSb11 is 20 x 10(exp -6) C(exp -1). Simply joining a Yb14MnSb11 and a SiGe leg to a common hot shoe could be expected to result in significant thermal stresses in either or both legs during operation. Heretofore, such thermal stresses have been regarded as disadvantageous. In the proposed approach, stresses resulting from the CTE mismatch would be turned to advantage.

  19. Hot Leg Piping Materials Issues

    SciTech Connect

    V. Munne

    2006-07-19

    With Naval Reactors (NR) approval of the Naval Reactors Prime Contractor Team (NRPCT) recommendation to develop a gas cooled reactor directly coupled to a Brayton power conversion system as the space nuclear power plant (SNPP) for Project Prometheus (References a and b) the reactor outlet piping was recognized to require a design that utilizes internal insulation (Reference c). The initial pipe design suggested ceramic fiber blanket as the insulation material based on requirements associated with service temperature capability within the expected range, very low thermal conductivity, and low density. Nevertheless, it was not considered to be well suited for internal insulation use because its very high surface area and proclivity for holding adsorbed gases, especially water, would make outgassing a source of contaminant gases in the He-Xe working fluid. Additionally, ceramic fiber blanket insulating materials become very friable after relatively short service periods at working temperatures and small pieces of fiber could be dislodged and contaminate the system. Consequently, alternative insulation materials were sought that would have comparable thermal properties and density but superior structural integrity and greatly reduced outgassing. This letter provides technical information regarding insulation and materials issues for the Hot Leg Piping preconceptual design developed for the Project Prometheus space nuclear power plant (SNPP).

  20. Cold energy

    SciTech Connect

    Wallace, John P.

    2015-12-04

    Deviations in Q for resonant superconducting radio frequency niobium accelerator cavities are generally correlated with resistivity loss mechanisms. Field dependent Qs are not well modeled by these classical loss mechanisms, but rather can represent a form of precision cavity surface thermometry. When the field dependent Q variation shows improvement with increasing B field level the classical treatment of this problem is inadequate. To justify this behavior hydrogen as a ubiquitous impurity in niobium, which creates measurable property changes, even at very low concentrations is typically considered the cause of such anomalous behavior. This maybe the case in some instances, but more importantly any system operating with a highly coherent field with a significant time dependent magnetic component at near 2° K will have the ability to organize the remaining free spins within the London penetration depth to form a coupled energy reservoir in the form of low mass spin waves. The niobium resonant cavities are composed of a single isotope with a large nuclear spin. When the other loss mechanisms are stripped away this may be the gain medium activated by the low level residual magnetic fields. It was found that one resonant cavity heat treatment produced optimum surface properties and then functioned as a MASER extracting energy from the 2° K thermal bath while cooling the cavity walls. The cavity operating in this mode is a simulator of what can take place in the wider but not colder universe using the cosmic microwave background (CMB) as a thermal source. The low mass, long lifetimes, and the scale of the magnetic spin waves on the weakly magnetized interstellar medium allows energy to be stored that is many orders of magnitude colder than the cosmic microwave background. A linear accelerator cavity becomes a tool to explore the properties of the long wave length magnetic spin waves that populate this cold low energy regime.

  1. Cold remedies (image)

    MedlinePlus

    Sore throat, cough, stuffy nose, sneezing, runny nose, fever, chills, and muscle aches are all symptoms associated with the common cold. Over-the-counter medicines for a cold only alleviate cold symptoms but do not shorten the duration of a cold. As always, ...

  2. California Red-legged Frog - Stipulated Injunction

    EPA Pesticide Factsheets

    EPA will make effects determinations and initiate consultation with the U.S. Fish and Wildlife Service, regarding the potential effects of 66 pesticide active ingredient registrations on the California red-legged frog.

  3. Support Leg Loading in Punt Kicking

    ERIC Educational Resources Information Center

    Kermond, John; Konz, Stephen

    1978-01-01

    Maximum distance in football punt kicking is associated with a maximum force transfer to the ball rather than a maximum force transfer through the ground via the support leg. For maximum distance, tred lightly. (Author)

  4. Desensitization of menthol-activated cold receptors in lower extremities during local cooling in young women with a cold constitution.

    PubMed

    Yamazaki, Fumio; Sone, Ryoko

    2017-03-01

    To test the hypothesis that topical menthol-induced reactivity of cold sensation and cutaneous vasoconstriction to local cooling is augmented in individuals with a cold constitution, we examined thermal sensation and cutaneous vasoconstrictor responses at menthol-treated and untreated sites in the legs during local skin cooling in young women complaining of chilliness (C group) and young women with no complaint as a normal control group (N group). During local skin cooling, the sensitivity to cold sensation was greater in the C group than in the N group. The application of menthol enhanced the cold sensation at a low temperature in the N group, but not in the C group. Cutaneous vasoconstrictor responses to local skin cooling were not altered by menthol treatment in either of the two groups. These findings suggest the desensitization of menthol-activated cold receptors in the legs of C group subjects, and a minor role of cold receptor activity in cutaneous vasoconstrictor response to local cooling.

  5. Microgravity, Mesh-Crawling Legged Robots

    NASA Technical Reports Server (NTRS)

    Behar, Alberto; Marzwell, Neville; Matthews, Jaret; Richardson, Krandalyn; Wall, Jonathan; Poole, Michael; Foor, David; Rodgers, Damian

    2008-01-01

    The design, fabrication, and microgravity flight-testing are part of a continuing development of palm-sized mobile robots that resemble spiders (except that they have six legs apiece, whereas a spider has eight legs). Denoted SpiderBots (see figure), they are prototypes of proposed product line of relatively inexpensive walking robots that could be deployed in large numbers to function cooperatively in construction, repair, exploration, search, and rescue activities in connection with exploration of outer space and remote planets.

  6. Rotational joint assembly for the prosthetic leg

    NASA Technical Reports Server (NTRS)

    Owens, L. J.; Jones, W. C. (Inventor)

    1977-01-01

    A rotational joint assembly for a prosthetic leg has been devised, which enables an artificial foot to rotate slightly when a person is walking, running or turning. The prosthetic leg includes upper and lower tubular members with the rotational joint assembly interposed between them. The assembly includes a restrainer mechanism which consists of a pivotably mounted paddle element. This device applies limiting force to control the rotation of the foot and also restores torque to return the foot back to its initial position.

  7. Passive legged, multi-segmented, robotic vehicle.

    SciTech Connect

    Hayward, David R.

    2003-11-01

    The Passive-legged, Multi-segmented, Robotic Vehicle concept is a simple legged vehicle that is modular and scaleable, and can be sized to fit through confined areas that are slightly larger than the size of the vehicle. A specific goal of this project was to be able to fit through the opening in the fabric of a chain link fence. This terrain agile robotic platform will be composed of multiple segments that are each equipped with appendages (legs) that resemble oars extending from a boat. Motion is achieved by pushing with these legs that can also flex to fold next to the body when passing through a constricted area. Each segment is attached to another segment using an actuated joint. This joint represents the only actuation required for mobility. The major feature of this type of mobility is that the terrain agility advantage of legs can be attained without the complexity of the multiple-actuation normally required for the many joints of an active leg. The minimum number of segments is two, but some concepts require three or more segments. This report discusses several concepts for achieving this type of mobility, their design, and the results obtained for each.

  8. In Situ Field Measurement of Leaf Water Potential Using Thermocouple Psychrometers 1

    PubMed Central

    Savage, Michael J.; Wiebe, Herman H.; Cass, Alfred

    1983-01-01

    Thermocouple psychrometers are the only instruments which can measure the in situ water potential of intact leaves, and which can possibly be used to monitor leaf water potential. Unfortunately, their usefulness is limited by a number of difficulties, among them fluctuating temperatures and temperature gradients within the psychrometer, sealing of the psychrometer chamber to the leaf, shading of the leaf by the psychrometer, and resistance to water vapor diffusion by the cuticle when the stomates are closed. Using Citrus jambhiri, we have tested several psychrometer design and operational modifications and showed that in situ psychrometric measurements compared favorably with simultaneous Scholander pressure chamber measurements on neighboring leaves when the latter were corrected for the osmotic potential. PMID:16663267

  9. Boiling point measurement of a small amount of brake fluid by thermocouple and its application.

    PubMed

    Mogami, Kazunari

    2002-09-01

    This study describes a new method for measuring the boiling point of a small amount of brake fluid using a thermocouple and a pear shaped flask. The boiling point of brake fluid was directly measured with an accuracy that was within approximately 3 C of that determined by the Japanese Industrial Standards method, even though the sample volume was only a few milliliters. The method was applied to measure the boiling points of brake fluid samples from automobiles. It was clear that the boiling points of brake fluid from some automobiles dropped to approximately 140 C from about 230 C, and that one of the samples from the wheel cylinder was approximately 45 C lower than brake fluid from the reserve tank. It is essential to take samples from the wheel cylinder, as this is most easily subjected to heating.

  10. High temperature thermocouple and heat flux gauge using a unique thin film-hardware hot juncture

    NASA Technical Reports Server (NTRS)

    Liebert, C. H.; Holanda, R.; Hippensteele, S. A.; Andracchio, C. A.

    1984-01-01

    A special thin film-hardware material thermocouple (TC) and heat flux gauge concept for a reasonably high temperature and high flux flat plate heat transfer experiment was fabricated and tested to gauge temperatures of 911 K. This concept was developed for minimal disturbance of boundary layer temperature and flow over the plates and minimal disturbance of heat flux through the plates. Comparison of special heat flux gauge Stanton number output at steady-state conditions with benchmark literature data was good and agreement was within a calculated uncertainty of the measurement system. Also, good agreement of special TC and standard TC outputs was obtained and the results are encouraging. Oxidation of thin film thermoelements was a primary failure mode after about 5 of operation.

  11. Operating Temperatures of a Sodium-Cooled Exhaust Valve as Measured by a Thermocouple

    NASA Technical Reports Server (NTRS)

    Sanders, J C; Wilsted, H D; Mulcahy, B A

    1943-01-01

    Report presents the results of a thermocouple installed in the crown of a sodium-cooled exhaust valve. The valve was tested in an air-cooled engine cylinder and valve temperatures under various engine operating conditions were determined. A temperature of 1337 degrees F. was observed at a fuel-air ratio of 0.064, a brake mean effective pressure of 179 pounds per square inch, and an engine speed of 2000 r.p.m. Fuel-air ratio was found to have a large influence on valve temperature, but cooling-air pressure and variation in spark advance had little effect. An increase in engine power by change of speed or mean effective pressure increased the valve temperature. It was found that the temperature of the rear-spark-plug bushing was not a satisfactory indication of the temperature of the exhaust valve.

  12. Operating Temperatures of a Sodium-Cooled Exhaust Valve as Measured by a Thermocouple

    NASA Technical Reports Server (NTRS)

    Sanders, J. C.; Wilsted, H. D.; Mulcahy, B. A.

    1943-01-01

    A thermocouple was installed in the crown of a sodium-cooled exhaust valve. The valve was then tested in an air-cooled engine cylinder and valve temperatures under various engine operating conditions were determined. A temperature of 1337 F was observed at a fuel-air ratio of 0.064, a brake mean effective pressure of 179 pounds per square inch, and an engine speed of 2000 rpm. Fuel-air ratio was found to have a large influence on valve temperature, but cooling-air pressure and variation in spark advance had little effect. An increase in engine power by change of speed or mean effective pressure increased the valve temperature. It was found that the temperature of the rear spark-plug bushing was not a satisfactory indication of the temperature of the exhaust valve.

  13. Fabrication and Use of Thin-film Thermocouples on Nonmetallics in Gas Turbine Engines

    NASA Astrophysics Data System (ADS)

    Niska, Raymond H.

    2003-09-01

    The gas turbine engine industry has been developing nonmetallics such as ceramic matrix composites (CMCs) and monolithic silicon nitride for use in hot-section hardware. New product development requires characterization of the hardware during component and engine testing. Of primary importance in propulsion engine hot sections such as the combustor and turbines is knowledge of thermal patterns and profiles, identification of hot streaks, and component maximum temperatures. This is especially critical information to estimate hardware life and time-in-service between required maintenance inspections and teardowns. Thin-film thermocouples and flame-sprayed aluminum oxide installation methods have been developed and are being used for temperature measurements on these new materials.

  14. Peltier effect exchanges in contact thermocouples - Application to the characterization of new thermoelectric circuits

    NASA Astrophysics Data System (ADS)

    Berrached, N.-E.

    Results from an investigation of coupling in thermoelectric circuits manufactured by electrodeposition of a metallic conductor on a conducting foil made of a different material are presented. The study was undertaken to define the significant factors in the design and manufacture of thermal fluxmeters. Theoretical considerations indicate that the voltage appearing between output connections is proportional to the average spatial thermal gradient on the sensitive surface of the thermoelement. A figure of merit is defined for the coupling of the contact thermocouples. Localized thermal exchanges of opposite sign are shown to occur due to the passage of current, and are concentrated at the boundaries of each thermoelement. Nonisothermal tangential thermal gradients appear on the surface of the circuit. Experimental studies confirm the appearance of the gradients by their IR signatures. Finally, the gradients are determined to be affected by the thickness and conductivity of the medium placed between the emitter and detector circuits.

  15. Time-series investigation of anomalous thermocouple responses in a liquid-metal-cooled reactor

    SciTech Connect

    Gross, K.C.; Planchon, H.P.; Poloncsik, J.

    1988-03-24

    A study was undertaken using SAS software to investigate the origin of anomalous temperature measurements recorded by thermocouples (TCs) in an instrumented fuel assembly in a liquid-metal-cooled nuclear reactor. SAS macros that implement univariate and bivariate spectral decomposition techniques were employed to analyze data recorded during a series of experiments conducted at full reactor power. For each experiment, data from physical sensors in the tests assembly were digitized at a sampling rate of 2/s and recorded on magnetic tapes for subsequent interactive processing with CMS SAS. Results from spectral and cross-correlation analyses led to the identification of a flow rate-dependent electromotive force (EMF) phenomenon as the origin of the anomalous TC readings. Knowledge of the physical mechanism responsible for the discrepant TC signals enabled us to device and justify a simple correction factor to be applied to future readings.

  16. Tile Surface Thermocouple Measurement Challenges from the Orbiter Boundary Layer Transition Flight Experiment

    NASA Technical Reports Server (NTRS)

    Campbell, Charles H.; Berger, Karen; Anderson, Brian

    2012-01-01

    Hypersonic entry flight testing motivated by efforts seeking to characterize boundary layer transition on the Space Shuttle Orbiters have identified challenges in our ability to acquire high quality quantitative surface temperature measurements versus time. Five missions near the end of the Space Shuttle Program implemented a tile surface protuberance as a boundary layer trip together with tile surface thermocouples to capture temperature measurements during entry. Similar engineering implementations of these measurements on Discovery and Endeavor demonstrated unexpected measurement voltage response during the high heating portion of the entry trajectory. An assessment has been performed to characterize possible causes of the issues experienced during STS-119, STS-128, STS-131, STS-133 and STS-134 as well as similar issues encountered during other orbiter entries.

  17. [Pentoxifylline medication within the scope of leg-ulcer therapy. Results of a field study using Trental 400].

    PubMed

    Pemler, K; Penth, B; Adams, H J

    1979-06-07

    513 patients with chronic ulcers of the leg were treated with Trental 400 orally in addition to local therapy. Regarding the reduction of the symptoms: ulcer extension, coldness of the leg, paraesthesia, resting pain and improvement of walking distance, 215 patients were classified as considerably improved, 195 distinctly improved, 53 slightly improved and 44 unchanged. Four cases worsened, two cases could not be classified. The possibility of combining oral therapy with local treatment and surgical measures (skin-flaps) is shown in three case reports. Gastro-intestinal tolerance of Trental 400 was good, interactions with concomitantly administered drugs were not reported.

  18. Ankle Joint Angle and Lower Leg Musculotendinous Unit Responses to Cryotherapy.

    PubMed

    Akehi, Kazuma; Long, Blaine C; Warren, Aric J; Goad, Carla L

    2016-09-01

    Akehi, K, Long, BC, Warren, AJ, and Goad, CL. Ankle joint angle and lower leg musculotendinous unit responses to cryotherapy. J Strength Cond Res 30(9): 2482-2492, 2016-The use of cold application has been debated for its influence on joint range of motion (ROM) and stiffness. The purpose of this study was to determine whether a 30-minute ice bag application to the plantarflexor muscles or ankle influences passive ankle dorsiflexion ROM and lower leg musculotendinous stiffness (MTS). Thirty-five recreationally active college-aged individuals with no history of lower leg injury 6 months before data collection volunteered. On each testing day, we measured maximum passive ankle dorsiflexion ROM (°) and plantarflexor torque (N·m) on an isokinetic dynamometer to calculate the passive plantarflexor MTS (N·m per degree) at 4 joint angles before, during, and after a treatment. Surface electromyography amplitudes (μV), and skin surface and ambient air temperature (°C) were also measured. Subjects received an ice bag to the posterior lower leg, ankle joint, or nothing for 30 minutes in different days. Ice bag application to the lower leg and ankle did not influence passive ROM (F(12,396) = 0.67, p = 0.78). Passive torque increased after ice bag application to the lower leg (F(12,396) = 2.21, p = 0.011). Passive MTS at the initial joint angle increased after ice bag application to the lower leg (F(12,396) = 2.14, p = 0.014) but not at the other joint angles (p > 0.05). Surface electromyography amplitudes for gastrocnemius and soleus muscles increased after ice application to the lower leg (F(2,66) = 5.61, p = 0.006; F(12,396) = 3.60, p < 0.001). Ice bag application to the lower leg and ankle joint does not alter passive dorsiflexion ROM but increases passive ankle plantarflexor torque in addition to passive ankle plantarflexor MTS at the initial joint angle.

  19. Investigation of the viscous heating artefact arising from the use of thermocouples in a focused ultrasound field

    NASA Astrophysics Data System (ADS)

    Morris, Hugh; Rivens, Ian; Shaw, Adam; ter Haar, Gail

    2008-09-01

    Accurate temperature measurements in therapeutic ultrasound fields are necessary for understanding damage mechanisms, verification of thermal modelling and calibration of non-invasive clinical thermometry. However, artefactual heating, primarily due to viscous forces which result from motion relative to the surrounding tissue, occurs when metal thermocouples are used in an ultrasound field. The magnitude and time dependence of this artefact has been characterized by comparison with novel thin-film thermocouples (TFTs) at 1-2 cm focal depths in fresh degassed ex vivo bovine liver. High-intensity focused ultrasound exposures (1.7 MHz; free-field spatial-peak temporal-average intensities 40-600 W cm-2) were used. Subtraction of the TFT data from that obtained for other thermocouples yielded the time dependence of the viscous heating artefact. This was found to be intensity independent up to 600 W cm-2 (below the threshold for cavitation and lesion formation) and remained significant at radial distances out to the first side lobe in the focal plane. The contribution of viscous heating to cooling was also found to be significant for at least 5 s after the end of insonation. The ratio of viscous artefact to absorptive heating after 5 s was: 1.76 ± 0.07 for a fine-wire, 0.45 ± 0.07 and 1.93 ± 0.07 for two different sheathed-wires and 0.24 ± 0.07 for a needle thermocouple.

  20. Investigation of the viscous heating artefact arising from the use of thermocouples in a focused ultrasound field.

    PubMed

    Morris, Hugh; Rivens, Ian; Shaw, Adam; Haar, Gail Ter

    2008-09-07

    Accurate temperature measurements in therapeutic ultrasound fields are necessary for understanding damage mechanisms, verification of thermal modelling and calibration of non-invasive clinical thermometry. However, artefactual heating, primarily due to viscous forces which result from motion relative to the surrounding tissue, occurs when metal thermocouples are used in an ultrasound field. The magnitude and time dependence of this artefact has been characterized by comparison with novel thin-film thermocouples (TFTs) at 1-2 cm focal depths in fresh degassed ex vivo bovine liver. High-intensity focused ultrasound exposures (1.7 MHz; free-field spatial-peak temporal-average intensities 40-600 W cm(-2)) were used. Subtraction of the TFT data from that obtained for other thermocouples yielded the time dependence of the viscous heating artefact. This was found to be intensity independent up to 600 W cm(-2) (below the threshold for cavitation and lesion formation) and remained significant at radial distances out to the first side lobe in the focal plane. The contribution of viscous heating to cooling was also found to be significant for at least 5 s after the end of insonation. The ratio of viscous artefact to absorptive heating after 5 s was: 1.76 +/- 0.07 for a fine-wire, 0.45 +/- 0.07 and 1.93 +/- 0.07 for two different sheathed-wires and 0.24 +/- 0.07 for a needle thermocouple.

  1. Cold Stress and the Cold Pressor Test

    ERIC Educational Resources Information Center

    Silverthorn, Dee U.; Michael, Joel

    2013-01-01

    Temperature and other environmental stressors are known to affect blood pressure and heart rate. In this activity, students perform the cold pressor test, demonstrating increased blood pressure during a 1- to 2-min immersion of one hand in ice water. The cold pressor test is used clinically to evaluate autonomic and left ventricular function. This…

  2. Increasing trunk flexion transforms human leg function into that of birds despite different leg morphology.

    PubMed

    Aminiaghdam, Soran; Rode, Christian; Müller, Roy; Blickhan, Reinhard

    2017-02-01

    Pronograde trunk orientation in small birds causes prominent intra-limb asymmetries in the leg function. As yet, it is not clear whether these asymmetries induced by the trunk reflect general constraints on the leg function regardless of the specific leg architecture or size of the species. To address this, we instructed 12 human volunteers to walk at a self-selected velocity with four postures: regular erect, or with 30 deg, 50 deg and maximal trunk flexion. In addition, we simulated the axial leg force (along the line connecting hip and centre of pressure) using two simple models: spring and damper in series, and parallel spring and damper. As trunk flexion increases, lower limb joints become more flexed during stance. Similar to birds, the associated posterior shift of the hip relative to the centre of mass leads to a shorter leg at toe-off than at touchdown, and to a flatter angle of attack and a steeper leg angle at toe-off. Furthermore, walking with maximal trunk flexion induces right-skewed vertical and horizontal ground reaction force profiles comparable to those in birds. Interestingly, the spring and damper in series model provides a superior prediction of the axial leg force across trunk-flexed gaits compared with the parallel spring and damper model; in regular erect gait, the damper does not substantially improve the reproduction of the human axial leg force. In conclusion, mimicking the pronograde locomotion of birds by bending the trunk forward in humans causes a leg function similar to that of birds despite the different morphology of the segmented legs.

  3. Leg extension is an important predictor of paretic leg propulsion in hemiparetic walking.

    PubMed

    Peterson, Carrie L; Cheng, Jing; Kautz, Steven A; Neptune, Richard R

    2010-10-01

    Forward propulsion is a central task of walking that depends on the generation of appropriate anterior-posterior ground reaction forces (AP GRFs). The AP impulse (i.e., time integral of the AP GRF) generated by the paretic leg relative to the non-paretic leg is a quantitative measure of the paretic leg's contribution to forward propulsion and is variable across hemiparetic subjects. The purpose of this study was to investigate the underlying mechanisms of propulsion generation in hemiparetic walking by identifying the biomechanical predictors of AP impulses. Three-dimensional kinematics and GRFs were recorded from 51 hemiparetic and 21 age-matched control subjects walking at similar speeds on an instrumented treadmill. Hierarchical regression models were generated for each leg to predict the AP impulse from independent biomechanical variables. Leg extension was a significant predictor and positively related to the propulsive impulse in the paretic, non-paretic and control legs. Secondarily, the hip flexor moment impulse was negatively related to the propulsive impulse. Also, the relationship of paretic and non-paretic ankle moments with the propulsive impulse depended on the paretic step ratio, suggesting the plantar flexor contribution to the propulsive impulse depends on leg angle. These results suggest that increasing paretic leg extension will increase propulsion. Increasing paretic plantar flexor output and decreasing paretic hip flexor output could also increase paretic leg propulsion. While increased pre-swing hip flexor output has been suggested to compensate for decreased plantar flexor output, such output may further impair propulsion by the paretic leg if it occurs too soon in the gait cycle.

  4. High temperature exposure of in-situ thermocouple fixed-point cells: stability with up to three months of continuous use

    NASA Astrophysics Data System (ADS)

    Elliott, C. J.; Greenen, A.; Lowe, D.; Pearce, J. V.; Machin, G.

    2015-04-01

    To categorise thermocouples in batches, manufacturers state an expected operating tolerance for when the thermocouples are as-new. In use, thermocouple behaviour can rapidly change and the tolerance becomes invalid, especially when used at high temperatures (i.e. above 1000 °C) as the processes leading to de-calibration, such as oxidation and contamination, can be very fast and lead to erroneous readings. In-situ thermocouple self-validation provides a method to track the drift and correct the thermocouple reading in real-time, but it must be shown to be reliable. Two miniature temperature fixed-point cells designed at NPL for in-situ thermocouple self-validation, the first containing a Pt-C eutectic alloy and the second containing a Ru-C eutectic alloy, have been exposed to temperatures close to their melting point for 2200 h and 1570 h, respectively, and continuously, for up to three months. Recalibration after this long-term high-temperature exposure, where a tantalum-sheathed thermocouple was always in place, is used to show that no significant change of the temperature reference point (the melting temperature) has occurred in either the Pt-C ingot or the Ru-C ingot, over timescales far longer than previously demonstrated and approaching that required by industry for practical use of the device.

  5. Cold and Cough Medicines

    MedlinePlus

    ... What can you do for your cold or cough symptoms? Besides drinking lots of fluids and getting ... medicines. There are lots of different cold and cough medicines, and they do different things. Nasal decongestants - ...

  6. Cold medicines and children

    MedlinePlus

    ... aspx . Accessed July 26, 2016. Cherry JD. The common cold. In: Cherry JD, Harrison GJ, Kaplan SL, Steinbach ... 2014:chap 7. Miller EK, Williams JV. The common cold. In: Kliegman RM, Stanton BF, St. Geme JW, ...

  7. Skin Reactions to Cold

    PubMed Central

    Talpash, Orest

    1976-01-01

    Although skin reactions to cold are seen surprisingly infrequently in Canada, it is important to manage them correctly when they do occur. Frostbite, cold urticarias, Raynaud's disease and phenomenon, and several miscellaneous changes are discussed. PMID:21308019

  8. Cold knife cone biopsy

    MedlinePlus

    ... biopsy; Pap smear - cone biopsy; HPV - cone biopsy; Human papilloma virus - cone biopsy; Cervix - cone biopsy; Colposcopy - cone biopsy Images Female reproductive anatomy Cold cone biopsy Cold cone removal References American ...

  9. Conjoined legs: Sirenomelia or caudal regression syndrome?

    PubMed Central

    Das, Sakti Prasad; Ojha, Niranjan; Ganesh, G Shankar; Mohanty, Ram Narayan

    2013-01-01

    Presence of single umbilical persistent vitelline artery distinguishes sirenomelia from caudal regression syndrome. We report a case of a12-year-old boy who had bilateral umbilical arteries presented with fusion of both legs in the lower one third of leg. Both feet were rudimentary. The right foot had a valgus rocker-bottom deformity. All toes were present but rudimentary. The left foot showed absence of all toes. Physical examination showed left tibia vara. The chest evaluation in sitting revealed pigeon chest and elevated right shoulder. Posterior examination of the trunk showed thoracic scoliosis with convexity to right. The patient was operated and at 1 year followup the boy had two separate legs with a good aesthetic and functional results. PMID:23960288

  10. Dimensional synthesis of a leg mechanism

    NASA Astrophysics Data System (ADS)

    Pop, F.; Lovasz, E.-Ch; Pop, C.; Dolga, V.

    2016-08-01

    An eight bar leg mechanism dimensional synthesis is presented. The mathematical model regarding the synthesis is described and the results obtained after computation are verified with help of 2D mechanism simulation in Matlab. This mechanism, inspired from proposed solution of Theo Jansen, is integrated into the structure of a 2 DOF quadruped robot. With help of the kinematic synthesis method described, it is tried to determine new dimensions for the mechanism, based on a set of initial conditions. These are established by taking into account the movement of the end point of the leg mechanism, which enters in contact with the ground, during walking. An optimization process based on the results obtained can be conducted further in order to find a better solution for the leg mechanism.

  11. Probabilistic Mechanical Reliability Prediction of Thermoelectric Legs

    SciTech Connect

    Jadaan, Osama M.; Wereszczak, Andrew A

    2009-05-01

    The probability of failure, Pf, for various square-arrayed thermoelectric device designs using bismuth telluride, lead telluride, or skutterudite thermoelectric materials were estimated. Only volume- or bulk-based Pf analysis was considered in this study. The effects of the choice of the thermoelectric material, the size of the leg array, the height of the thermoelectric legs, and the boundary conditions on the Pf of thermoelectric devices were investigated. Yielding of the solder contacts and mounting layer was taken into account. The modeling results showed that the use of longer legs, using skutterudites, allowing the thermoelectric device to freely deform while under a thermal gradient, and using smaller arrays promoted higher probabilities of survival.

  12. Sympathetic adaptations to one-legged training

    NASA Technical Reports Server (NTRS)

    Ray, C. A.

    1999-01-01

    The purpose of the present study was to determine the effect of leg exercise training on sympathetic nerve responses at rest and during dynamic exercise. Six men were trained by using high-intensity interval and prolonged continuous one-legged cycling 4 day/wk, 40 min/day, for 6 wk. Heart rate, mean arterial pressure (MAP), and muscle sympathetic nerve activity (MSNA; peroneal nerve) were measured during 3 min of upright dynamic one-legged knee extensions at 40 W before and after training. After training, peak oxygen uptake in the trained leg increased 19 +/- 2% (P < 0.01). At rest, heart rate decreased from 77 +/- 3 to 71 +/- 6 beats/min (P < 0.01) with no significant changes in MAP (91 +/- 7 to 91 +/- 11 mmHg) and MSNA (29 +/- 3 to 28 +/- 1 bursts/min). During exercise, both heart rate and MAP were lower after training (108 +/- 5 to 96 +/- 5 beats/min and 132 +/- 8 to 119 +/- 4 mmHg, respectively, during the third minute of exercise; P < 0.01). MSNA decreased similarly from rest during the first 2 min of exercise both before and after training. However, MSNA was significantly less during the third minute of exercise after training (32 +/- 2 to 22 +/- 3 bursts/min; P < 0.01). This training effect on MSNA remained when MSNA was expressed as bursts per 100 heartbeats. Responses to exercise in five untrained control subjects were not different at 0 and 6 wk. These results demonstrate that exercise training prolongs the decrease in MSNA during upright leg exercise and indicates that attenuation of MSNA to exercise reported with forearm training also occurs with leg training.

  13. Leg spasticity and ambulation in multiple sclerosis.

    PubMed

    Balantrapu, Swathi; Sosnoff, Jacob J; Pula, John H; Sandroff, Brian M; Motl, Robert W

    2014-01-01

    Background. Spasticity of the legs is common in multiple sclerosis (MS), but there has been limited research examining its association with ambulatory outcomes. Objective. This study examined spasticity of the legs and its association with multiple measures of ambulation in persons with MS. Methods. The sample included 84 patients with MS. Spasticity of the legs was measured using a 5-point rating scale ranging between 0 (normal) and 4 (contracted). Patients completed the 6-minute walk (6 MW), timed 25 foot walk (T25FW), and timed up-and-go (TUG), and O2 cost of walking was measured during the 6 MW. The patients undertook two walking trials on a GAITRite (CIR systems, Inc.) for measuring spatial and temporal parameters of gait. The patients completed the Multiple Sclerosis Walking Scale-12 (MSWS-12) and wore an accelerometer over a seven-day period. Results. 52% (n = 44) of the sample presented with spasticity of the legs. Those with leg spasticity had significantly worse ambulation as measured by 6 MW (P = 0.0001, d = -0.86), T25FW (P = 0.003, d = 0.72), TUG (P = 0.001, d = 0.84), MSWS-12 (P = 0.0001, d = 1.09), O2 cost of walking (P = 0.001, d = 0.75), average steps/day (P < 0.05, d = -0.45), and walking velocity (P < 0.05, d = -0.53) and cadence (P < 0.05, d = -0.46). Conclusion. Leg spasticity was associated with impairments in ambulation, including alterations in spatiotemporal parameters and free-living walking.

  14. Leg Spasticity and Ambulation in Multiple Sclerosis

    PubMed Central

    Balantrapu, Swathi; Sosnoff, Jacob J.; Pula, John H.; Sandroff, Brian M.; Motl, Robert W.

    2014-01-01

    Background. Spasticity of the legs is common in multiple sclerosis (MS), but there has been limited research examining its association with ambulatory outcomes. Objective. This study examined spasticity of the legs and its association with multiple measures of ambulation in persons with MS. Methods. The sample included 84 patients with MS. Spasticity of the legs was measured using a 5-point rating scale ranging between 0 (normal) and 4 (contracted). Patients completed the 6-minute walk (6 MW), timed 25 foot walk (T25FW), and timed up-and-go (TUG), and O2 cost of walking was measured during the 6 MW. The patients undertook two walking trials on a GAITRite (CIR systems, Inc.) for measuring spatial and temporal parameters of gait. The patients completed the Multiple Sclerosis Walking Scale-12 (MSWS-12) and wore an accelerometer over a seven-day period. Results. 52% (n = 44) of the sample presented with spasticity of the legs. Those with leg spasticity had significantly worse ambulation as measured by 6 MW (P = 0.0001, d = −0.86), T25FW (P = 0.003, d = 0.72), TUG (P = 0.001, d = 0.84), MSWS-12 (P = 0.0001, d = 1.09), O2 cost of walking (P = 0.001, d = 0.75), average steps/day (P < 0.05, d = −0.45), and walking velocity (P < 0.05, d = −0.53) and cadence (P < 0.05, d = −0.46). Conclusion. Leg spasticity was associated with impairments in ambulation, including alterations in spatiotemporal parameters and free-living walking. PMID:24999434

  15. Stripes on a 6-leg Hubbard ladder.

    PubMed

    White, Steven R; Scalapino, D J

    2003-09-26

    While density matrix renormalization group calculations find stripes on doped n-leg t-J ladders, little is known about the possible formation of stripes on n-leg Hubbard ladders. Here we report results for a 7x6 Hubbard model with four holes. We find that a stripe forms for values of U/t ranging from 6 to 20. For U/t approximately 3-4, the system exhibits the domain wall feature of a stripe, but the hole density is very broadened.

  16. Realizing the promise of robotic leg prostheses.

    PubMed

    Goldfarb, Michael; Lawson, Brian E; Shultz, Amanda H

    2013-11-06

    Recent advances in robotics technology are enabling the emergence of robotic leg prostheses that can emulate the full biomechanical functionality of the healthy limb. The behavior of such prostheses is software-controllable, in an analogous manner to the way in which the central nervous system controls the human musculoskeletal system. Although these prostheses have the capability of reproducing the biomechanical behavior of the healthy limb, their ability to do so is a function of how well the prosthesis control system coordinates the movement of the leg with the movement of the user.

  17. Summary Results of the Neptun Boil-Off Experiments to Investigate the Accuracy and Cooling Influence of LOFT Cladding-Surface Thermocouples (System 00)

    SciTech Connect

    E. L. Tolman S. N. Aksan

    1981-10-01

    Nine boil-off experiments were conducted in the Swiss NEPTUN Facility primarily to obtain experimental data for assessing the perturbation effects of LOFT thermocouples during simulated small-break core uncovery conditions. The data will also be useful in assessing computer model capability to predict thermal hydraulic response data for this type of experiment. System parameters that were varied for these experiments included heater rod power, system pressure, and initial coolant subcooling. The experiments showed that the LOFT thermocouples do not cause a significant cooling influence in the rods to which they are attached. Furthermore, the accuracy of the LOFT thermocouples is within 20 K at the peak cladding temperature zone.

  18. Preparation of W-Ta thin-film thermocouple on diamond anvil cell for in-situ temperature measurement under high pressure

    NASA Astrophysics Data System (ADS)

    Yang, Jie; Li, Ming; Zhang, Honglin; Gao, Chunxiao

    2011-04-01

    In this paper, a W-Ta thin-film thermocouple has been integrated on a diamond anvil cell by thin-film deposition and photolithography methods. The thermocouple was calibrated and its thermal electromotive force was studied under high pressure. The results indicate that the thermal electromotive force of the thermocouple exhibits a linear relationship with temperature and is not associated with pressure. The resistivity measurement of ZnS powders under high pressure at different temperatures shows that the phase transition pressure decreases as the temperature increases.

  19. Preparation of W-Ta thin-film thermocouple on diamond anvil cell for in-situ temperature measurement under high pressure.

    PubMed

    Yang, Jie; Li, Ming; Zhang, Honglin; Gao, Chunxiao

    2011-04-01

    In this paper, a W-Ta thin-film thermocouple has been integrated on a diamond anvil cell by thin-film deposition and photolithography methods. The thermocouple was calibrated and its thermal electromotive force was studied under high pressure. The results indicate that the thermal electromotive force of the thermocouple exhibits a linear relationship with temperature and is not associated with pressure. The resistivity measurement of ZnS powders under high pressure at different temperatures shows that the phase transition pressure decreases as the temperature increases.

  20. Preparation of W-Ta thin-film thermocouple on diamond anvil cell for in-situ temperature measurement under high pressure

    SciTech Connect

    Yang Jie; Li Ming; Zhang Honglin; Gao Chunxiao

    2011-04-15

    In this paper, a W-Ta thin-film thermocouple has been integrated on a diamond anvil cell by thin-film deposition and photolithography methods. The thermocouple was calibrated and its thermal electromotive force was studied under high pressure. The results indicate that the thermal electromotive force of the thermocouple exhibits a linear relationship with temperature and is not associated with pressure. The resistivity measurement of ZnS powders under high pressure at different temperatures shows that the phase transition pressure decreases as the temperature increases.

  1. Respiratory-Related Leg Movements and Their Relationship with Periodic Leg Movements During Sleep

    PubMed Central

    Manconi, Mauro; Zavalko, Irina; Bassetti, Claudio L.; Colamartino, Elisabetta; Pons, Marco; Ferri, Raffaele

    2014-01-01

    Study Objectives: To describe the time structure of leg movements (LM) in obstructive sleep apnea (OSA) syndrome, in order to advance understanding of their clinical significance. Location: Sleep Research Centre, Oasi Institute (IRCCS), Troina, Italy. Setting: Sleep laboratory. Patients: Eighty-four patients (16 females, 68 males, mean age 55.1 y, range 29-74 y). Methods: Respiratory-related leg movements (RRLM) and those unrelated to respiratory events (NRLM) were examined within diagnostic polysomnograms alone and together for their distributions within the sleep period and for their periodicity. Measurements and Results: Patients with OSA and RRLM exhibited more periodic leg movements in sleep (PLMS), particularly in NREM sleep. A gradual decrease in number of NRLM across the sleep period was observed in patients with RRLM. This pattern was less clear for RRLM. Frequency histograms of intermovement intervals of all LMs in patients with RRLM showed a prominent first peak at 4 sec, and a second peak at approximately 24 sec coincident with that of PLMS occurring in the absence of OSA. A third peak of lowest amplitude was the broadest with a maximum at approximately 42 sec. In patients lacking RRLM, NRLM were evident with a single peak at 2-4 sec. A stepwise linear regression analysis showed that, after controlling for a diagnosis of restless legs syndrome and apnea-hypopnea index, PLMS remained significantly associated with RRLM. Conclusion: The time structure of leg movements occurring in conjunction with respiratory events exhibit features of periodic leg movements in sleep occurring alone, only with a different and longer period. This brings into question the validity, both biologic and clinical, of scoring conventions with their a priori exclusion from consideration as periodic leg movements in sleep. Citation: Manconi M; Zavalko I; Bassetti CL; Colamartino E; Pons M; Ferri R. Respiratory-related leg movements and their relationship with periodic leg movements

  2. [The influence of the leg load and the support mobility under leg on the anticipatory postural adjustment].

    PubMed

    Kazennikov, O V; Kireeva, T B; Shlykov, V Iu

    2015-01-01

    Anticipatory postural adjustment is an essential part of equilibrium maintainance during standing in human. So changes in stance condition could affect both control of equilibrium and anticipatory adjustment. Anticipatory changes in the stabilogram of each leg were studied in standing subject during the early stage of quick right arm lifting while legs were on two separated supports. The center of pressure (CP) movement was analyzed in three variants of experiment: both legs on immovable support, with only right leg on the movable support and with only left leg on the moveable support. In each standing condition subject stood with symmetrical load on two legs or with the load voluntary transferred to one leg. The anticipatory CP shift depended on the mobility of the support under the leg and on loading of the leg. While standing on unmovable supports with symmetrical load on the legs before lifting of the right arm CP of right leg shifted backward and CP of left leg--forward. While standing with one leg on movable support the anticipatory CP shift of this leg was small and did not depend on the load on the leg. However the shift of CP of the leg that was placed on the unmovable support depended on the load in the same way as in the case when both legs were on unmovable supports. Results suggested that since on movable support the support and proprioceptive afferent flow from distal part of the leg that was did not supply unambiguous information about body position, the role of distal joints in posture control is reduced.

  3. Thermocouple psychrometer measurements of in situ water potential changes in heated welded tuff

    SciTech Connect

    Mao, Nai-hsien; Wang, H.F.

    1991-10-01

    Ten thermocouple psychrometers (TCPs) to measure water potential (WP) were installed in three holes in G-Tunnel at the Nevada Test Site as part of the Prototype Engineered Barrier System Field Tests. We calibrated the TCPs in NaCl solutions up to 80{degrees}C (176{degrees}F) in the laboratory. In two holes, we used rubber sleeves and packers to house TCPs, and in the third hole, we used foam. All three holes were grouted behind the TCP assemblages. The initial moisture condition indicated by TCP data was about 99.5% relative humidity or a WP of about {minus}5 bar. This corresponded to 15.4 g/m{sup 3} of water in the air near the borehole wall, which was much wetter than we expected. A drying and re-wetting cycle peaked at about day 140 with a WP of {minus}65 bar in borehole P3, located below the heater. A similar cycle but reduced in scale was found at about day 175 with a WP of {minus}45 bar in borehole P2, above the heater. This difference is drying behavior above and below the heater was also observed from neutron data and was explained as a gravity effect.

  4. Thermocouple and infrared sensor-based measurement of temperature distribution in metal cutting.

    PubMed

    Kus, Abdil; Isik, Yahya; Cakir, M Cemal; Coşkun, Salih; Özdemir, Kadir

    2015-01-12

    In metal cutting, the magnitude of the temperature at the tool-chip interface is a function of the cutting parameters. This temperature directly affects production; therefore, increased research on the role of cutting temperatures can lead to improved machining operations. In this study, tool temperature was estimated by simultaneous temperature measurement employing both a K-type thermocouple and an infrared radiation (IR) pyrometer to measure the tool-chip interface temperature. Due to the complexity of the machining processes, the integration of different measuring techniques was necessary in order to obtain consistent temperature data. The thermal analysis results were compared via the ANSYS finite element method. Experiments were carried out in dry machining using workpiece material of AISI 4140 alloy steel that was heat treated by an induction process to a hardness of 50 HRC. A PVD TiAlN-TiN-coated WNVG 080404-IC907 carbide insert was used during the turning process. The results showed that with increasing cutting speed, feed rate and depth of cut, the tool temperature increased; the cutting speed was found to be the most effective parameter in assessing the temperature rise. The heat distribution of the cutting tool, tool-chip interface and workpiece provided effective and useful data for the optimization of selected cutting parameters during orthogonal machining.

  5. Modeling of the Thermal Footprint at the Strike Point and Fast Thermocouples in Carbon Tiles

    NASA Astrophysics Data System (ADS)

    Nygren, R. E.; Watkins, J. G.; Buchenauer, D. A.; Makowski, M. A.; Leonard, A. W.

    2013-10-01

    Thermal broadening can complicate interpretation of IR images at the strike point because the peaked profile of surface temperature widens as the tile heats due to lateral conduction away from the peak, so the instantaneous values of λq extracted from IR images increases during the shot. Detailed 3D thermal analyses of divertor tiles complement data from edge probes, fast thermocouples (FTCs) and IR thermography and aids interpretation. But the surface temperature reflects the integrated heat load over time, so changes in power or movement of the plasma complicates this interpretation. The array of 16 embedded FTCs in DIII-D divertor tiles are 8 mm below the surface.The poster focuses on the degree to which the FTCs can help resolve the absolute value of the surface temperature and the extracted profile of surface temperature and related peaked heat load.We include a series of detailed 3D thermal analyses of one DIII-D tile exposed to a (theoretical) peaked heat load characterized by the commonly-used two-parameter fit. Work supported by the US DOE under DE-AC04-94AL85000, DE-AC52-07N27344 & DE-FC02-04ER54698.

  6. In-situ temperature measurement in lithium ion battery by transferable flexible thin film thermocouples

    NASA Astrophysics Data System (ADS)

    Mutyala, Madhu Santosh K.; Zhao, Jingzhou; Li, Jianyang; Pan, Hongen; Yuan, Chris; Li, Xiaochun

    2014-08-01

    Temperature monitoring is important for improving the safety and performance of Lithium Ion Batteries (LIB). This paper presents the feasibility study to insert flexible polymer embedded thin film thermocouples (TFTCs) in a lithium ion battery pouch cell for in-situ temperature monitoring. A technique to fabricate polyimide embedded TFTC sensors on glass substrates and later transfer it onto thin copper foils is presented. The sensor transfer process can be easily integrated into the assembly process of a pouch cell, thus holding promise in implementing in Battery Management Systems (BMS). Internal temperature of the LIB pouch cell was measured in-situ when the sensor embedded battery was operated at high rate charge-discharge cycles. The polyimide embedded TFTCs survived the battery assembly process and the battery electrolyte environment. It is observed that the heat generation inside the battery is dominant during the high-rate of discharges. The developed technique can serve to improve the battery safety and performance when implemented in battery management systems and enhance the understanding of heat generation and its effects.

  7. Thermocouple and Infrared Sensor-Based Measurement of Temperature Distribution in Metal Cutting

    PubMed Central

    Kus, Abdil; Isik, Yahya; Cakir, M. Cemal; Coşkun, Salih; Özdemir, Kadir

    2015-01-01

    In metal cutting, the magnitude of the temperature at the tool-chip interface is a function of the cutting parameters. This temperature directly affects production; therefore, increased research on the role of cutting temperatures can lead to improved machining operations. In this study, tool temperature was estimated by simultaneous temperature measurement employing both a K-type thermocouple and an infrared radiation (IR) pyrometer to measure the tool-chip interface temperature. Due to the complexity of the machining processes, the integration of different measuring techniques was necessary in order to obtain consistent temperature data. The thermal analysis results were compared via the ANSYS finite element method. Experiments were carried out in dry machining using workpiece material of AISI 4140 alloy steel that was heat treated by an induction process to a hardness of 50 HRC. A PVD TiAlN-TiN-coated WNVG 080404-IC907 carbide insert was used during the turning process. The results showed that with increasing cutting speed, feed rate and depth of cut, the tool temperature increased; the cutting speed was found to be the most effective parameter in assessing the temperature rise. The heat distribution of the cutting tool, tool-chip interface and workpiece provided effective and useful data for the optimization of selected cutting parameters during orthogonal machining. PMID:25587976

  8. Practical system for the direct measurement of magneto-caloric effect by micro-thermocouples.

    PubMed

    Kamarád, J; Kaštil, J; Arnold, Z

    2012-08-01

    A system for direct measurements of the magneto-caloric effect (MCE) exploits a rapid transport of a sample into or from magnetic field in permanent Halbach-type (1 T) or superconducting (4.7 T) magnets. Time dependence of induced changes of the sample temperature, ΔT(t), is detected directly by the differential Cu-Constantan-Cu micro-thermocouples with time steps of 300 ms. A sample placed inside an evacuated simple LN(2) cryostat is either totally isolated (adiabatic conditions) or partly connected with the copper sample holder (non-adiabatic conditions). The last arrangement (a model of the Brayton cycle) is used to simulate an application of MCE in refrigeration techniques. The relations describing ΔT(t) that allow an analysis of MCE of the studied materials are based on the general cooling law. The effect of the first-order magnetic transition on MCE of selected sample is also demonstrated by non-standard ΔT(t) curves measured in the last mentioned experimental arrangements.

  9. HIGH TEMPERATURE IRRADIATION RESISTANT THERMOCOUPLES – A LOW COST SENSOR FOR IN-PILE TESTING AT HIGH TEMPERATURES

    SciTech Connect

    Joy L. Rempe; Darrell L. Knudson; Keith G. Condie; S. Curtis Wilkins; Joshua E. Daw

    2008-06-01

    Several options have been identified to improve recently-developed Idaho National Laboratory (INL) High Temperature Irradiation Resistant ThermoCouples (HTIR-TCs) for in-pile testing. These options have the potential to reduce fabrication costs and allow HTIR-TC use in higher temperature applications (up to at least 1800 °C). The INL and the University of Idaho (UI) investigated these options with the ultimate objective of providing recommendations for alternate thermocouple designs that are optimized for various applications. This paper summarizes results from these INL/UI investigations. Specifically, results are reported about several options found to enhance HTIR-TC performance, such as improved heat treatments, alternate geometries, alternate fabrication techniques, and the use of copper/nickel alloys as soft extension cable.

  10. Proposal of a New Type Thin Film Vacuum Sensor Using the Short Circuit Current-Detection Type Thermocouple

    NASA Astrophysics Data System (ADS)

    Takashima, Noriaki; Kimura, Mitsuteru

    We have proposed the thin film vacuum sensor that has a cantilever structure with new temperature difference sensors of the short circuit Seebeck-Current-Detection type thermocouple in order to get higher sensitivity in the higher vacuum range. Temperature difference, which should be zero under the higher vacuum, between microheater and thermally isolated heading area from the microheater is measured under the vacuum pressure. Even a little temperature difference in our new sensor can be measured in very lower vacuum pressure range by the signal amplification than that of the traditional Pirani vacuum sensor. In our experiments, the short circuit Seebeck-Current-Detection type thermocouple is used to measure the very small temperature difference. Measurement of very wide vacuum pressure range between 105-10-2 Pa is achieved by the prototype sensor.

  11. Functional scoliosis caused by leg length discrepancy

    PubMed Central

    Daniszewska, Barbara; Zolynski, Krystian

    2010-01-01

    Introduction Leg length discrepancy (LLD) causes pelvic obliquity in the frontal plane and lumbar scoliosis with convexity towards the shorter extremity. Leg length discrepancy is observed in 3-15% of the population. Unequalized lower limb length discrepancy leads to posture deformation, gait asymmetry, low back pain and discopathy. Material and methods In the years 1998-2006, 369 children, aged 5 to 17 years (209 girls, 160 boys) with LLD-related functional scoliosis were treated. An external or internal shoe lift was applied. Results Among 369 children the discrepancy of 0.5 cm was observed in 27, 1 cm in 329, 1.5 cm in 9 and 2 cm in 4 children. During the first follow-up examination, within 2 weeks, the adjustment of the spine to new static conditions was noted and correction of the curve in 316 examined children (83.7%). In 53 children (14.7%) the correction was observed later and was accompanied by slight low back pain. The time needed for real equalization of limbs was 3 to 24 months. The time needed for real equalization of the discrepancy was 11.3 months. Conclusions Leg length discrepancy equalization results in elimination of scoliosis. Leg length discrepancy < 2 cm is a static disorder; that is why measurements should be performed in a standing position using blocks of adequate thickness and the position of the posterior superior iliac spine should be estimated. PMID:22371777

  12. Parental smoking during pregnancy shortens offspring's legs.

    PubMed

    Żądzińska, E; Kozieł, S; Borowska-Strugińska, B; Rosset, I; Sitek, A; Lorkiewicz, W

    2016-12-01

    One of the most severe detrimental environmental factors acting during pregnancy is foetal smoke exposure. The aim of this study was to assess the effect of maternal, paternal and parental smoking during pregnancy on relative leg length in 7- to 10-year-old children. The research conducted in the years 2001-2002 included 978 term-born children, 348 boys and 630 girls, at the age of 7-10 years. Information concerning the birth weight of a child was obtained from the health records of the women. Information about the mother's and the father's smoking habits during pregnancy and about the mothers' education level was obtained from a questionnaire. The influence of parental smoking on relative leg length, controlled for age, sex, birth weight and the mother's education, as a proxy measure of socioeconomic status, and controlled for an interaction between sex and birth weight, was assessed by an analysis of covariance, where relative leg length was the dependent variable, smoking and sex were the independent variables, and birth weight as well as the mother's education were the covariates. Three separate analyses were run for the three models of smoking habits during pregnancy: the mother's smoking, the father's smoking and both parents' smoking. Only both parents' smoking showed a significant effect on relative leg length of offspring. It is probable that foetal hypoxia caused by carbon monoxide contained in smoke decelerated the growth of the long bones of foetuses.

  13. Mechanics of six-legged runners.

    PubMed

    Full, R J; Tu, M S

    1990-01-01

    Six-legged pedestrians, cockroaches, use a running gait during locomotion. The gait was defined by measuring ground reaction forces and mechanical energy fluctuations of the center of mass in Blaberus discoidalis (Serville) as they travelled over a miniature force platform. These six-legged animals produce horizontal and vertical ground-reaction patterns of force similar to those found in two-, four- and eight-legged runners. Lateral forces were less than half the vertical force fluctuations. At speeds between 0.08 and 0.66 ms-1, horizontal kinetic and gravitational potential energy changes were in phase. This pattern of energy fluctuation characterizes the bouncing gaits used by other animals that run. Blaberus discoidalis attained a maximum sustainable stride frequency of 13 Hz at 0.35 ms-1, the same speed and frequency predicted for a mammal of the same mass. Despite differences in body form, the mass-specific energy used to move the center of mass a given distance (0.9 J kg-1m-1) was the same for cockroaches, ghost crabs, mammals, and birds. Similarities in force production, stride frequency and mechanical energy production during locomotion suggest that there may be common design constraints in terrestrial locomotion which scale with body mass and are relatively independent of body form, leg number and skeletal type.

  14. Chronic Lower Leg Pain in Athletes

    PubMed Central

    Brewer, Rachel Biber; Gregory, Andrew J. M.

    2012-01-01

    Context: Chronic lower leg pain in athletes can be a frustrating problem for patients and a difficult diagnosis for clinicians. Myriad approaches have been suggested to evaluate these conditions. With the continued evolution of diagnostic studies, evidence-based guidance for a standard approach is unfortunately sparse. Evidence Acquisition: PubMed was searched from January 1980 to May 2011 to identify publications regarding chronic lower leg pain in athletes (excluding conditions related to the foot), including differential diagnosis, clinical presentation, physical examination, history, diagnostic workup, and treatment. Results: Leg pain in athletes can be caused by many conditions, with the most frequent being medial tibial stress syndrome; chronic exertional compartment syndrome, stress fracture, nerve entrapment, and popliteal artery entrapment syndrome are also considerations. Conservative management is the mainstay of care for the majority of causes of chronic lower leg pain; however, surgical intervention may be necessary. Conclusion: Chronic lower extremity pain in athletes includes a wide differential and can pose diagnostic dilemmas for clinicians. PMID:23016078

  15. [Responses of Arma chinensis cold tolerance to rapid cold hardening and underlying physiological mechanisms].

    PubMed

    Li, Xing-Peng; Song, Li-Wen; Zhang, Hong-Hao; Chen, Yue-Qu; Zuo, Tong-Tong; Wang, Jun; Sun, Wei

    2012-03-01

    Rapid cold hardening can enhance the cold tolerance of some insects. To explore the effects of different cold hardening induction temperature on the cold tolerance of Arma chinensis and related physiological mechanisms, the 3rd generation A. chinensis adults reared indoor were treated with cooling at 15, 10, and 4 degrees C for 4 h, respectively, or with gradual cooling from 15 degrees C for 4 h to 10 degrees C for 4 h, and finally to 4 degrees C for 4 h. The super-cooling point, water content, and the contents of low molecular carbohydrates, glycerol, and amino acids of the adults after cooling and the adults cold tolerance at 0, -5, and -10 degrees C were measured by thermocouple, high performance liquid chromatography, and other analytical techniques. When exposed at -10 degrees C after cooling, the survival rate of the adults treated with gradual cooling or treated with cooling at 4 degrees C for 4 h was averagely 58.3%, while that of the adults reared at room temperature (25 degrees C +/- 2 degrees C) or treated with cooling at 15 degrees C or 10 degrees C for 4 h decreased significantly, with an average of 8.9%. The super-cooling point of the adults treated with gradual cooling or with cooling at 4 degrees C for 4 h was -15.6 degrees C, which was averagely 1.3 degrees C lower than that of the other treatments. The water content of the adults had no significant difference among all treatments, with an average of 61.8%, but the glucose, sorbitolum, glycerol, Ala, and Glu contents in treatments gradual cooling and cooling at 4 degrees C for 4 h increased by 2.82-fold, 2.65-fold, 3.49-fold, 51.3%, and 80.2%, while the fucose, mannose, and Pro contents decreased by 68.4%, 52.2%, and 30.2%, respectively, as compared with the other treatments. The fructose content showed no significant difference among all treatments. It was suggested that rapid cool hardening had a critical temperature to induce the physiological metabolism process of adult A. chinensis, and

  16. New fixed-point mini-cell to investigate thermocouple drift in a high-temperature environment under neutron irradiation

    SciTech Connect

    Laurie, M.; Vlahovic, L.; Rondinella, V.V.; Sadli, M.; Failleau, G.; Fuetterer, M.; Lapetite, J.M.; Fourrez, S.

    2015-07-01

    Temperature measurements in the nuclear field require a high degree of reliability and accuracy. Despite their sheathed form, thermocouples subjected to nuclear radiations undergo changes due to radiation damage and transmutation that lead to significant EMF drift during long-term fuel irradiation experiment. For the purpose of a High Temperature Reactor fuel irradiation to take place in the High Flux Reactor Petten, a dedicated fixed-point cell was jointly developed by LNE-Cnam and JRC-IET. The developed cell to be housed in the irradiation rig was tailor made to quantify the thermocouple drift during the irradiation (about two year duration) and withstand high temperature (in the range 950 deg. C - 1100 deg. C) in the presence of contaminated helium in a graphite environment. Considering the different levels of temperature achieved in the irradiation facility and the large palette of thermocouple types aimed at surveying the HTR fuel pebble during the qualification test both copper (1084.62 deg. C) and gold (1064.18 deg. C) fixed-point materials were considered. The aim of this paper is to first describe the fixed-point mini-cell designed to be embedded in the reactor rig and to discuss the preliminary results achieved during some out of pile tests as much as some robustness tests representative of the reactor scram scenarios. (authors)

  17. A thermocouple-based remote temperature controller of an electrically floated sample to study plasma CVD growth of carbon nanotube

    NASA Astrophysics Data System (ADS)

    Miura, Takuya; Xie, Wei; Yanase, Takashi; Nagahama, Taro; Shimada, Toshihiro

    2015-09-01

    Plasma chemical vapor deposition (CVD) is now gathering attention from a novel viewpoint, because it is easy to combine plasma processes and electrochemistry by applying a bias voltage to the sample. In order to explore electrochemistry during the plasma CVD, the temperature of the sample must be controlled precisely. In traditional equipment, the sample temperature is measured by a radiation thermometer. Since emissivity of the sample surface changes in the course of the CVD growth, it is difficult to measure the exact temperature using the radiation thermometer. In this work, we developed new equipment to control the temperature of electrically floated samples by thermocouple with Wi-Fi transmission. The growth of the CNT was investigated using our plasma CVD equipment. We examined the temperature accuracy and stability controlled by the thermocouple with monitoring the radiation thermometer. We noticed that the thermocouple readings were stable, whereas the readings of the radiation thermometer changes significantly (20 °C) during plasma CVD. This result clearly shows that the sample temperature should be measured with direct connection. On the result of CVD experiment, different structures of carbon including CNT were obtained by changing the bias voltages.

  18. Comparisons of Gas-phase Temperature Measurements in a Flame Using Thin-Filament Pyrometry and Thermocouples

    NASA Technical Reports Server (NTRS)

    Struk, Peter; Dietrich, Daniel; Valentine, Russell; Feier, Ioan

    2003-01-01

    Less-intrusive, fast-responding, and full-field temperature measurements have long been a desired tool for the research community. Recently, the emission of a silicon-carbide (SiC) fiber placed in a flowing hot (or reacting) gas has been used to measure the temperature profile along the length of the fiber. The relationship between the gas and fiber temperature comes from an energy balance on the fiber. In the present work, we compared single point flame temperature measurements using thin-filament pyrometry (TFP) and thermocouples. The data was from vertically traversing a thermocouple and a SiC fiber through a methanol/air diffusion flame of a porous-metal wick burner. The results showed that the gas temperature using the TFP technique agreed with the thermocouple measurements (25.4 m diameter wire) within 3.5% for temperatures above 1200 K. Additionally, we imaged the entire SiC fiber (with a spatial resolution of 0.14 mm) while it was in the flame using a high resolution CCD camera. The intensity level along the fiber length is a function of the temperature. This results in a one-dimensional temperature profiles at various heights above the burner wick. This temperature measurement technique, while having a precision of less than 1 K, showed data scatter as high as 38 K. Finally, we discuss the major sources of uncertainty in gas temperature measurement using TFP.

  19. Temperature distributions measurement of high intensity focused ultrasound using a thin-film thermocouple array and estimation of thermal error caused by viscous heating.

    PubMed

    Matsuki, Kosuke; Narumi, Ryuta; Azuma, Takashi; Yoshinaka, Kiyoshi; Sasaki, Akira; Okita, Kohei; Takagi, Shu; Matsumoto, Yoichiro

    2013-01-01

    To improve the throughput of high intensity focused ultrasound (HIFU) treatment, we have considered a focus switching method at two points. For this method, it is necessary to evaluate the thermal distribution under exposure to ultrasound. The thermal distribution was measured using a prototype thin-film thermocouple array, which has the advantage of minimizing the influence of the thermocouple on the acoustic and temperature fields. Focus switching was employed to enlarge the area of temperature increase and evaluate the proposed evaluation parameters with respect to safety and uniformity. The results indicate that focus switching can effectively expand the thermal lesion while maintaining a steep thermal boundary. In addition, the influence caused by the thin-film thermocouple array was estimated experimentally. This thermocouple was demonstrated to be an effective tool for the measurement of temperature distributions induced by HIFU.

  20. How cold is cold dark matter?

    SciTech Connect

    Armendariz-Picon, Cristian; Neelakanta, Jayanth T. E-mail: jtneelak@syr.edu

    2014-03-01

    If cold dark matter consists of particles, these must be non-interacting and non-relativistic by definition. In most cold dark matter models however, dark matter particles inherit a non-vanishing velocity dispersion from interactions in the early universe, a velocity that redshifts with cosmic expansion but certainly remains non-zero. In this article, we place model-independent constraints on the dark matter temperature to mass ratio, whose square root determines the dark matter velocity dispersion. We only assume that dark matter particles decoupled kinetically while non-relativistic, when galactic scales had not entered the horizon yet, and that their momentum distribution has been Maxwellian since that time. Under these assumptions, using cosmic microwave background and matter power spectrum observations, we place upper limits on the temperature to mass ratio of cold dark matter today (away from collapsed structures). These limits imply that the present cold dark matter velocity dispersion has to be smaller than 54 m/s. Cold dark matter has to be quite cold, indeed.

  1. Tandem wheel drop-legs for standard truck trailer

    NASA Technical Reports Server (NTRS)

    Cantwell, W.; Selstad, R.

    1970-01-01

    Tandem wheel drop-leg device provides a semitrailer with fore and aft mobility that allows it to be moved without a prime mover. The modified drop-legs have trunnion dual wheels and an adjustable brace.

  2. 11. NORTH VIEW OF INNER FACING OF SOUTHEASTERN LEG OF ...

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

    11. NORTH VIEW OF INNER FACING OF SOUTHEASTERN LEG OF SEA WALL. SOUTHERN END OF NORTHEASTERN LEG OF SEA WALL IN BACKGROUND. - Fort Delaware, Sea Wall, Pea Patch Island, Delaware City, New Castle County, DE

  3. A colored leg banding technique for Amazona parrots

    USGS Publications Warehouse

    Meyers, J.M.

    1995-01-01

    A technique for individual identification of Amazona was developed using plastic leg bands. Bands were made from 5- and 7-mm-wide strips of laminated PVC coiled 2.5 times with an inside diameter 4-5 mm gt the maximum diameter of the parrot's leg. Seventeen parrots were captured in Puerto Rico, marked with individual plastic leg bands, and observed for 204-658 d with only one lost or damaged plastic band. Plastic leg bands did not cause injury to or calluses on parrots' legs. The plastic material used for making leg bands was available in 18 colors in 1994, which would allow unique marking of 306 individuals using one plastic leg band on each leg.

  4. Cold plasma brush generated at atmospheric pressure

    SciTech Connect

    Duan Yixiang; Huang, C.; Yu, Q. S.

    2007-01-15

    A cold plasma brush is generated at atmospheric pressure with low power consumption in the level of several watts (as low as 4 W) up to tens of watts (up to 45 W). The plasma can be ignited and sustained in both continuous and pulsed modes with different plasma gases such as argon or helium, but argon was selected as a primary gas for use in this work. The brush-shaped plasma is formed and extended outside of the discharge chamber with typical dimension of 10-15 mm in width and less than 1.0 mm in thickness, which are adjustable by changing the discharge chamber design and operating conditions. The brush-shaped plasma provides some unique features and distinct nonequilibrium plasma characteristics. Temperature measurements using a thermocouple thermometer showed that the gas phase temperatures of the plasma brush are close to room temperature (as low as 42 deg. C) when running with a relatively high gas flow rate of about 3500 ml/min. For an argon plasma brush, the operating voltage from less than 500 V to about 2500 V was tested, with an argon gas flow rate varied from less than 1000 to 3500 ml/min. The cold plasma brush can most efficiently use the discharge power as well as the plasma gas for material and surface treatment. The very low power consumption of such an atmospheric argon plasma brush provides many unique advantages in practical applications including battery-powered operation and use in large-scale applications. Several polymer film samples were tested for surface treatment with the newly developed device, and successful changes of the wettability property from hydrophobic to hydrophilic were achieved within a few seconds.

  5. Integration of thermocouple microelectrode in the scanning electrochemical microscope at variable temperatures: simultaneous temperature and electrochemical imaging and its kinetic studies

    PubMed Central

    Pan, He; Zhang, Hailing; Lai, Junhui; Gu, Xiaoxin; Sun, Jianjun; Tang, Jing; Jin, Tao

    2017-01-01

    We describe herein a method for the simultaneous measurement of temperature and electrochemical signal with a new type of thermocouple microelectrode. The thermocouple microelectrode can be used not only as a thermometer but also as a scanning electrochemical microscope (SECM) tip in the reaction between tip-generated bromine and a heated Cu sample. The influence of temperature on the SECM imaging process and the related kinetic parameters have been studied, such as kinetic constant and activation energy. PMID:28338002

  6. Integration of thermocouple microelectrode in the scanning electrochemical microscope at variable temperatures: simultaneous temperature and electrochemical imaging and its kinetic studies

    NASA Astrophysics Data System (ADS)

    Pan, He; Zhang, Hailing; Lai, Junhui; Gu, Xiaoxin; Sun, Jianjun; Tang, Jing; Jin, Tao

    2017-03-01

    We describe herein a method for the simultaneous measurement of temperature and electrochemical signal with a new type of thermocouple microelectrode. The thermocouple microelectrode can be used not only as a thermometer but also as a scanning electrochemical microscope (SECM) tip in the reaction between tip-generated bromine and a heated Cu sample. The influence of temperature on the SECM imaging process and the related kinetic parameters have been studied, such as kinetic constant and activation energy.

  7. Acute leg volume changes in weightlessness and its simulation

    NASA Technical Reports Server (NTRS)

    Thornton, William E.; Uri, John J.; Hedge, Vickie; Coleman, Eugen; Moore, Thomas P.

    1992-01-01

    Leg volume changes were studied in six subjects during 150 min of horizontal, 6 deg headdown tilt and supine immersion. Results were compared to previously obtained space flight data. It is found that, at equivalent study times, the magnitude of the leg volume changes during the simulations was less than one half that seen during space flight. Relative and absolute losses from the upper leg were greater during space flight, while relative losses were greater from the lower leg during simulations.

  8. Venous Leg Ulcer in a Sarcoidosis Patient: A Case Report

    PubMed Central

    Ohn, Jungyoon; Byun, Sang Young; Kim, In Su

    2015-01-01

    Venous leg ulcers, the most common form of leg ulcers, are relevant to the pathogenicity of pericapillary fibrin cuff. Sarcoidosis, a multiorgan granulomatous disease, causes fibrin deposition in tissues. We report a case of a 50-year-old man with venous leg ulcers coexisting with sarcoidosis. On the basis of the histologic findings, we propose the hypothesis that sarcoidosis patients are prone to the development of venous leg ulcers. PMID:26719645

  9. Spider diffraction: a comparison of curved and straight legs

    SciTech Connect

    Richter, J.L.

    1984-06-15

    It has been known for some time that, if curved legs rather than the usual straight ones are used in the spider that supports the secondary optics in certain telescopes, the visible diffraction effect is reduced. Fraunhofer theory is used to calculate the diffraction effects due to the curved leg spider. Calculated and photographic diffraction patterns are compared for straight and curved leg spiders.

  10. Thermocouple tests: a quick-look report on failures during loss-of-fluid tests L2-6 (LOFT L2-6)

    SciTech Connect

    Anderson, R.L.; Cannon, C.P.

    1984-03-01

    Tests were conducted to determine the operating limits of fuel cladding thermocouples installed inside the fuel rods for the loss-of-fluid test (LOFT) F2 fuel bundle test. This investigation was conducted to determine (a) the range of time and temperature exposure over which reliable performance can be expected for the dual diameter, 0.040/0.020-in.-diam, Inconel-clad, MgO-insulated, type K thermocouples installed in the LOFT F2 fuel bundle, and (b) the effect of reactor fuel preconditioning at various reactor power levels. Grounded, ungrounded, and unjunctioned thermocouples were tested in temperature profiles estimated for reactor power levels of 8, 10, 12, and 14 kW/ft. The estimated peak temperature was 2160/sup 0/F for the highest power level. The effects of fuel preconditioning for eight hours at peak temperatures of 1950/sup 0/F were measured. The results showed that (a) in expected LOFT F2 temperature profiles, thermocouple read-out errors remained less than 1% up to a peak temperature of 1900 to 1950/sup 0/F; (b) thermocouple read-out errors from virtual junction effects increase rapidly with temperatures above 1950/sup 0/F; (c) wire breakage in peak temperature regions did not occur in any of the tests; and (d) thermocouple performance did not measurably improve nor degrade as a result of eight hours of preconditioning at 1950/sup 0/F. The test data taken with the estimated profiles establish an upper bound on performance errors.

  11. Performance of Pt-C, CrC-CrC, CrC-C, and Ru-C Fixed Points for Thermocouple Calibrations Above 1600 C

    NASA Astrophysics Data System (ADS)

    Pearce, J. V.; Elliott, C. J.; Lowe, D. H.; Failleau, G.; Deuzé, T.; Bourson, F.; Sadli, M.; Machin, G.

    2014-04-01

    A series of high-temperature fixed points (HTFPs) Pt-C (1738 , and Ru-C (1953 ) have been constructed at the National Physical Laboratory (NPL) and the Laboratoire National de métrologie et d'Essais and Conservatoire national des arts et métiers (LNE-Cnam). These are required for the calibration of high-temperature thermocouples in the framework of work package 6 of the European Metrology Research Programme IND01 project "HiTeMS." The goal of this work package is to establish a European capability that can determine low-uncertainty reference functions of non-standard high-temperature thermocouples. For reference functions to be widely applicable, measurements must be performed by more than one institute and preferably by more than one method. Due to the high price of the ingot materials, miniature HTFP cells are used. NPL and LNE-Cnam constructed their HTFP cells with different designs; these are described here, together with the performance of the cells using both radiation thermometry and thermocouples. The melting temperature of the Ru-C cells (for thermocouple calibrations) was determined using radiation thermometry at both NPL and LNE-Cnam, and the two results are compared. The suitability of the cells for calibration of W-Re and Rh-Ir thermocouples is evaluated, and some results are presented. Some discussion is given regarding the materials challenges when calibrating Rh-Ir thermocouples up to 2000 C.

  12. Long Hole Film Cooling Dataset for CFD Development . Part 1; Infrared Thermography and Thermocouple Surveys

    NASA Technical Reports Server (NTRS)

    Shyam, Vikram; Thurman, Douglas; Poinsatte, Phillip; Ameri, Ali; Eichele, Peter; Knight, James

    2013-01-01

    An experiment investigating flow and heat transfer of long (length to diameter ratio of 18) cylindrical film cooling holes has been completed. In this paper, the thermal field in the flow and on the surface of the film cooled flat plate is presented for nominal freestream turbulence intensities of 1.5 and 8 percent. The holes are inclined at 30deg above the downstream direction, injecting chilled air of density ratio 1.0 onto the surface of a flat plate. The diameter of the hole is 0.75 in. (0.01905 m) with center to center spacing (pitch) of 3 hole diameters. Coolant was injected into the mainstream flow at nominal blowing ratios of 0.5, 1.0, 1.5, and 2.0. The Reynolds number of the freestream was approximately 11,000 based on hole diameter. Thermocouple surveys were used to characterize the thermal field. Infrared thermography was used to determine the adiabatic film effectiveness on the plate. Hotwire anemometry was used to provide flowfield physics and turbulence measurements. The results are compared to existing data in the literature. The aim of this work is to produce a benchmark dataset for Computational Fluid Dynamics (CFD) development to eliminate the effects of hole length to diameter ratio and to improve resolution in the near-hole region. In this report, a Time-Filtered Navier Stokes (TFNS), also known as Partially Resolved Navier Stokes (PRNS), method that was implemented in the Glenn-HT code is used to model coolant-mainstream interaction. This method is a high fidelity unsteady method that aims to represent large scale flow features and mixing more accurately.

  13. [Cold-induced urticaria].

    PubMed

    Delorme, N; Drouet, M; Thibaudeau, A; Verret, J L

    2002-09-01

    Cold urticaria is characterized by the development of urticaria, usually superficial and/or angioedematous reaction after cold contact. It was found predominantly in young women. The diagnosis is based on the history and ice cube test. Patients with a negative ice cube test may have represented systemic cold urticaria (atypical acquired cold urticaria) induced by general body cooling. The pathogenesis is poorly understood. Cold urticaria can be classified into acquired and familial disorders, with an autosomal dominant inheritance. Idiopathic cold urticaria is most common type but the research of a cryopathy is necessary. Therapy is often difficult. It is essential that the patient be warned of the dangers of swimming in cold water because systemic hypotension can occur. H1 antihistamines can be used for treatment of cold urticaria but the clinical responses are highly variable. The combination with an H2 antagonists is more effective. Doxepin may be useful in the treatment. Leukotriene receptor antagonists may be a novel, promising drug entity. In patients who do not respond to previous treatments, induction of cold tolerance may be tried.

  14. Cold fusion, Alchemist's dream

    SciTech Connect

    Clayton, E.D.

    1989-09-01

    In this report the following topics relating to cold fusion are discussed: muon catalysed cold fusion; piezonuclear fusion; sundry explanations pertaining to cold fusion; cosmic ray muon catalysed cold fusion; vibrational mechanisms in excited states of D{sub 2} molecules; barrier penetration probabilities within the hydrogenated metal lattice/piezonuclear fusion; branching ratios of D{sub 2} fusion at low energies; fusion of deuterons into {sup 4}He; secondary D+T fusion within the hydrogenated metal lattice; {sup 3}He to {sup 4}He ratio within the metal lattice; shock induced fusion; and anomalously high isotopic ratios of {sup 3}He/{sup 4}He.

  15. [Cellular therapy and leg ulcers: Future approaches].

    PubMed

    Senet, P

    2015-01-01

    The prevalence of leg ulcers, which are most commonly caused by venous insufficiency, is high in Europe. Current treatments are fairly unsatisfactory, with long healing times in many cases, as well as a high risk of relapse. Over the last 15 years, improved understanding of the cellular and molecular mechanisms at work in delayed wound healing has contributed to the development of cellular therapy in this field. The use of keratinocytes or cultured fibroblasts, whether autogenic or allogenic, has been of little value in terms of either healing times or rates of complete healing. For the moment, there are very few allogenic skin substitutes available; they are expensive and have been insufficiently studied in the indication of leg ulcers. Pluripotent mesenchymal adult stem cells have proved capable of accelerating wound healing in animal models and their study in chronic wounds in humans is currently awaited.

  16. Hemodynamic studies of the legs under weightlessness

    NASA Technical Reports Server (NTRS)

    Thornton, W. E.; Hoffler, G. W.

    1974-01-01

    Following exposure to weightlessness, alterations in the return of blood from the legs play a crucial role in orthostatic tolerance and may be an important factor in work tolerance. To investigate some of the hemodynamic mechansism involved, an experiment was performed on the Skylab 3 and Skylab 4 missions to study arterial blood flow, venous compliance, and muscle pumping of blood. Skylab 4 results indicated that the most likely cause of increased blood flow was an increase in cardiac output secondary to increased central venous pressure caused by blood redistribution. Changes in venous compliance are thought to be primarily changes in somatic musculature which is postulated to primarily determine venous compliance of the legs. This was also thought to be demonstrated by the changes in muscle pumping. It is thought that these compliance changes, when taken with the decreased blood volume; provide a basis for the changes seen in orthostatic tolerance, work capacity and lower body negative pressure response.

  17. Multi-leg heat pipe evaporator

    NASA Astrophysics Data System (ADS)

    Alario, J. P.; Haslett, R. A.

    1986-04-01

    A multileg heat pipe evaporator facilitates the use and application of a monogroove heat pipe by providing an evaporation section which is compact in area and structurally more compatible with certain heat exchangers or heat input apparatus. The evaporation section of a monogroove heat pipe is formed by a series of parallel legs having a liquid and a vapor channel and a communicating capillary slot therebetween. The liquid and vapor channels and interconnecting capillary slots of the evaporating section are connected to the condensing section of the heat pipe by a manifold connecting liquid and vapor channels of the parallel evaporation section legs with the corresponding liquid and vapor channels of the condensing section.

  18. Driving performance in cold, warm, and thermoneutral environments.

    PubMed

    Daanen, Hein A M; van de Vliert, Evert; Huang, Xu

    2003-11-01

    Driving performance deteriorates at high ambient temperatures. Less is known about the effect of low ambient temperatures and the role of subjective aspects like thermal comfort and having control over the ambient temperature. Therefore, an experiment was constructed in which 50 subjects performed a road-tracking task in a cold (5 degrees C), a thermoneutral (20 degrees C) or a warm (35 degrees C) climate. All subjects had a heater/blower (H/B) which generated a fixed amount of heat/wind that could either be controlled or not controlled. In the cold climate, averaged leg skin temperature dropped to 18.5 degrees C and head skin temperature to 24.9 degrees C; the thermal comfort was rated between 'cold' and 'very cold'. In the warm climate, averaged leg skin temperature rose to 36.6 degrees C and head skin temperature to 30.8 degrees C; the thermal comfort was rated as 'hot'. Driving performance in the ambient temperature extremes decreased 16% in the cold environment and 13% in the warm situation. Having control over the local head temperature by adjusting a H/B affected neither thermal comfort nor driving performance. In agreement with the literature on priming effects, subjects who started with the no-control condition performed much better in all driving tasks because they were primed to focus on the driving task as such, rather than the complex combination of temperature controls and driving task. It can be concluded that a thermoneutral temperature in a car enhances driving performance and may thus positively affect safety. Using manual climatic controls in hot or cold cars may interfere with the driving task.

  19. Dynamic legged locomotion in robots and animals

    NASA Astrophysics Data System (ADS)

    Raibert, Marc; Playter, Robert; Ringrose, Robert; Bailey, Dave; Leeser, Karl

    1995-01-01

    This report documents our study of active legged systems that balance actively and move dynamically. The purpose of this research is to build a foundation of knowledge that can lead both to the construction of useful legged vehicles and to a better understanding of how animal locomotion works. In this report we provide an update on progress during the past year. Here are the topics covered in this report: (1) Is cockroach locomotion dynamic? To address this question we created three models of cockroaches, each abstracted at a different level. We provided each model with a control system and computer simulation. One set of results suggests that 'Groucho Running,' a type of dynamic walking, seems feasible at cockroach scale. (2) How do bipeds shift weight between the legs? We built a simple planar biped robot specifically to explore this question. It shifts its weight from one curved foot to the other, using a toe-off and toe-on strategy, in conjunction with dynamic tipping. (3) 3D biped gymnastics: The 3D biped robot has done front somersaults in the laboratory. The robot changes its leg length in flight to control rotation rate. This in turn provides a mechanism for controlling the landing attitude of the robot once airborne. (4) Passively stabilized layout somersault: We have found that the passive structure of a gymnast, the configuration of masses and compliances, can stabilize inherently unstable maneuvers. This means that body biomechanics could play a larger role in controlling behavior than is generally thought. We used a physical 'doll' model and computer simulation to illustrate the point. (5) Twisting: Some gymnastic maneuvers require twisting. We are studying how to couple the biomechanics of the system to its control to produce efficient, stable twisting maneuvers.

  20. Efficiency and Speed in Legged Robots

    DTIC Science & Technology

    2011-03-22

    Alexander, Gregory Czerniak , Dr. Dave Bednarz and Sean Hadley, my co-authors on related conference publications. My committee members Professor C. J...2008) Bipedal Walkiing Army Science Conference. Orlando, FL. 102 Muench. P., Cheok, K. C., Czerniak , G., & Bednarz, D. (2009). Optimal Time and...Muench, P., Cheok, K.C., Czerniak , G., (2010) Optimal Powering Schemes for Legged Robotics. SPl£. Orlando, FL. NeIder. 1. A., and Mead, R. (1965). A

  1. Pharmacologic treatment of venous leg ulcers.

    PubMed

    Dormandy, J A

    1995-01-01

    In terms of prevalence, total cost and morbidity, venous leg ulcers are probably by far the most important type of ulcerations in the leg. The macrocirculatory defect leading to a raised ambulatory venous pressure is now accepted as a common initial pathologic pathway. Most current treatment modalities, such as surgery or external compression, are designed to control the macrovascular defect. However, it is the microcirculatory consequences of the venous hypertension that give rise to the trophic skin changes and ultimately to ulceration. At this microcirculatory level, pharmacotherapy may be a useful adjunct in the treatment of venous leg ulcers. The microcirculatory pathophysiologic changes include decreased fibrinolytic activity, elevated plasma fibrinogen, microcirculatory thrombi, and inappropriate activation of the white blood cells. The oxidative burst from the activated white cells probably plays a key role by releasing locally leukocyte-derived free radicals, proteolytic enzymes, cytokines, platelet-activating factor, and a number of other noxious mediators. An important additional component in recalcitrant venous ulcers is co-existing arterial disease, which is probably present in 15-20% of cases. Decreased arterial perfusion pressure will further aggravate the ischemic changes caused by the venous hypertension. Pentoxifylline downregulates leukocyte activation, reduces leukocyte adhesion, and also has fibrinolytic effects. A number of clinical studies have therefore been carried out to examine the clinical efficacy of pentoxifylline in treatment of venous leg ulcers. Probably the largest published placebo-controlled, double-blind randomized study was reported in 1990. In this study, 80 patients received either pentoxifylline 400 mg three times a day orally or matching placebo for 6 months or until their reference ulcer healed if this occurred sooner. Complete healing of the reference ulcer occurred in 23 of the 38 patients treated with pentoxifylline

  2. Energy Efficient Legged Robotics at Sandia Labs

    SciTech Connect

    Buerger, Steve

    2014-12-16

    Sandia is developing energy efficient actuation and drive train technologies to dramatically improve the charge life of legged robots. The work is supported by DARPA, and Sandia will demonstrate an energy efficient bipedal robot at the technology exposition section of the DARPA Robotics Challenge Finals in June, 2015. This video, the first in a series, describes early development and initial integration of the Sandia Transmission Efficient Prototype Promoting Research (STEPPR) robot.

  3. Energy Efficient Legged Robotics at Sandia Labs

    ScienceCinema

    Buerger, Steve

    2016-07-12

    Sandia is developing energy efficient actuation and drive train technologies to dramatically improve the charge life of legged robots. The work is supported by DARPA, and Sandia will demonstrate an energy efficient bipedal robot at the technology exposition section of the DARPA Robotics Challenge Finals in June, 2015. This video, the first in a series, describes early development and initial integration of the Sandia Transmission Efficient Prototype Promoting Research (STEPPR) robot.

  4. Leg contracture in mice: an assay of normal tissue response

    SciTech Connect

    Stone, H.B.

    1984-07-01

    Leg contracture, defined as the difference in extensibility of the control and irradiated hind legs of mice, was found to correlate with single doses of radiation from about 20 to 80 Gy. The time of development of the early phase of the response coincided with that reported for the appearance of the acute skin response, and in some cases, partially reversed as this reaction healed. The contracture then progressed again at a moderate rate through 90 days, and then more slowly through one year. Skin contraction, measured by decrease in intertattoo distance, was assayed in the same mice. It followed the same time course as leg contracture, but had a different dose-response relationship. To determine the contribution of skin contraction to the overall leg contracture response, mice were sacrificed and the leg contracture measured before and after the removal of the skin of the leg. After doses of up to 30 Gy, little contracture remained from skinning the leg, indicating that skin contraction was largely responsible for leg contracture in this dose range. After doses of about 45 Gy and above, some contracture remained in the skinned legs, although less than in intact legs. There was little or no enhancement of either skin contraction or leg contracture by the hypoxic cell sensitizers metronidazole or misonidazole.

  5. Leg edema from intrathecal opiate infusions.

    PubMed

    Aldrete, J A; Couto da Silva JM

    2000-01-01

    Despite the increasing popularity of intrathecal infusions to treat patients with long-term non-cancer-related pain, this therapy is not without serious side-effects. Five out of 23 patients who had intrathecal infusions of opiates for longer than 24 months developed leg and feet edema. As predisposing factors, cardiovascular disease, deep venous thrombosis, peripheral vascular disease, and venous stasis of the lower extremities were considered. Every patient who developed pedal and leg edema after the implantation of an infusion pump was also found to have leg edema and venous stasis prior to the time when the pump was inserted. This complication was severe enough to limit their physical activity, and to produce lymphedema, ulcerations and hyperpigmentation of the skin. Reduction of the edema occurred when the dose of the opiate was decreased, and in two cases in which the infusion was discontinued, there was almost complete resolution of the syndrome. It appears that the pre-existence of pedal edema and of venous stasis is a relative contraindication to the long-term intrathecal infusion of opiates in patients with chronic non-cancer pain.

  6. Legged-locomotion on inclined granular media

    NASA Astrophysics Data System (ADS)

    Rieser, Jennifer; Qian, Feifei; Goldman, Daniel

    Animals traverse a wide variety of complex environments, including situations in which the ground beneath them can yield (e.g. dry granular media in desert dunes). Locomotion strategies that are effective on level granular media can fail when traversing a granular slope. Taking inspiration from successful legged-locomotors in sandy, uneven settings, we explore the ability of a small (15 cm long, 100 g), six-c-shaped legged robot to run uphill in a bed of 1-mm-diameter poppy seeds, using an alternating tripod gait. Our fully automated experiments reveal that locomotor performance can depend sensitively on both environmental parameters such as the inclination angle and volume fraction of the substrate, and robot morphology and control parameters like leg shape, step frequency, and the friction between the feet of the robot and the substrate. We assess performance by measuring the average speed of the robot, and we find that the robot tends to perform better at higher step frequency and lower inclination angles, and that average speed decreases more rapidly with increasing angle for higher step frequency.

  7. Pyoderma vegetans developed on chronic leg ulcer.

    PubMed

    Molodoi, Andreea Dana; Dimitriu, Andreea; Andronic, Cătălina Diana; Stoleriu, Gabriela; Bădescu, Aida; Boda, D; Brănisteanu, Daciana Elena

    2015-01-01

    Pyoderma vegetans is a rare disorder that more commonly affects middle-aged persons, with a male predilection. It is characterized by vegetating lesions that coalescence into a plaque with eroded surface, covered by purulent discharge and crusts. The etiology of this disease is not known with certainty, but it is often associated with bacterial infections in immunocompromised patients. We report the case of a 73-year-old men who presented to the Iasi Dermatology Clinic with a large, irregular, relatively well-defined dermohypodermic ulcer, with infiltrated sclerosing borders, accompanied by pain, with the floor covered in the Northern part by a proliferative, vegetative bleeding area, and the rest by a yellowish secretion and cellular debris, located on the left leg. Bacteriological examination of ulcer secretion identified Pseudomonas aeruginosa. Anatomopathological examination confirmed the development of Pyoderma vegetans on chronic leg ulcer. Under specific treatment for chronic leg ulcer and eradication of infectious focus the outcome was favorable both in terms of trophic ulcer scar- ring and Pyoderma vegetans healing.

  8. Proprioceptive Actuation Design for Dynamic Legged locomotion

    NASA Astrophysics Data System (ADS)

    Kim, Sangbae; Wensing, Patrick; Biomimetic Robotics Lab Team

    Designing an actuator system for highly-dynamic legged locomotion exhibited by animals has been one of the grand challenges in robotics research. Conventional actuators designed for manufacturing applications have difficulty satisfying challenging requirements for high-speed locomotion, such as the need for high torque density and the ability to manage dynamic physical interactions. It is critical to introduce a new actuator design paradigm and provide guidelines for its incorporation in future mobile robots for research and industry. To this end, we suggest a paradigm called proprioceptive actuation, which enables highly- dynamic operation in legged machines. Proprioceptive actuation uses collocated force control at the joints to effectively control contact interactions at the feet under dynamic conditions. In the realm of legged machines, this paradigm provides a unique combination of high torque density, high-bandwidth force control, and the ability to mitigate impacts through backdrivability. Results show that the proposed design provides an impact mitigation factor that is comparable to other quadruped designs with series springs to handle impact. The paradigm is shown to enable the MIT Cheetah to manage the application of contact forces during dynamic bounding, with results given down to contact times of 85ms and peak forces over 450N. As a result, the MIT Cheetah achieves high-speed 3D running up to 13mph and jumping over an 18-inch high obstacle. The project is sponsored by DARPA M3 program.

  9. Electrical, Thermal, and Mechanical Characterization of Novel Segmented-Leg Thermoelectric Modules

    NASA Astrophysics Data System (ADS)

    D'Angelo, Jonathan; Case, Eldon D.; Matchanov, Nuraddin; Wu, Chun-I.; Hogan, Timothy P.; Barnard, James; Cauchy, Charles; Hendricks, Terry; Kanatzidis, Mercouri G.

    2011-10-01

    In this paper we report on the electrical, thermal, and mechanical characterization of segmented-leg PbTe-based thermoelectric modules. This work featured a thermoelectric module measurement system that was constructed and used to measure 47-couple segmented thermoelectric power generation modules fabricated by Tellurex Corporation using n-type Bi2Te3- x Se x to Ag0.86Pb19+ x SbTe20 legs and p-type Bi x Sb2- x Te3 to Ag0.9Pb9Sn9Sb0.6Te20 legs. The modules were measured under vacuum with hot-side and cold-side temperatures of approximately 670 K and 312 K, respectively. In addition, the measurements on the PbTe-based materials are compared with measurements performed on Bi2Te3 reference modules. Efficiency values as high as 6.56% were measured on these modules. In addition to the measurement system description and the measurement results on these modules, infrared images of the modules that were used to help identify nonuniformities are also presented.

  10. Cold stress and the cold pressor test.

    PubMed

    Silverthorn, Dee U; Michael, Joel

    2013-03-01

    Temperature and other environmental stressors are known to affect blood pressure and heart rate. In this activity, students perform the cold pressor test, demonstrating increased blood pressure during a 1- to 2-min immersion of one hand in ice water. The cold pressor test is used clinically to evaluate autonomic and left ventricular function. This activity is easily adapted to an inquiry format that asks students to go to the scientific literature to learn about the test and then design a protocol for carrying out the test in classmates. The data collected are ideal for teaching graphical presentation of data and statistical analysis.

  11. What's new: Management of venous leg ulcers: Approach to venous leg ulcers.

    PubMed

    Alavi, Afsaneh; Sibbald, R Gary; Phillips, Tania J; Miller, O Fred; Margolis, David J; Marston, William; Woo, Kevin; Romanelli, Marco; Kirsner, Robert S

    2016-04-01

    Leg ulcerations are a common problem, with an estimated prevalence of 1% to 2% in the adult population. Venous leg ulcers are primarily treated in outpatient settings and often are managed by dermatologists. Recent advances in the diagnosis and treatment of leg ulcers combined with available evidence-based data will provide an update on this topic. A systematized approach and the judicious use of expensive advanced therapeutics are critical. Specialized arterial and venous studies are most commonly noninvasive. The ankle brachial pressure index can be performed with a handheld Doppler unit at the bedside by most clinicians. The vascular laboratory results and duplex Doppler findings are used to identify segmental defects and potential operative candidates. Studies of the venous system can also predict a subset of patients who may benefit from surgery. Successful leg ulcer management requires an interdisciplinary team to make the correct diagnosis, assess the vascular supply, and identify other modifiable factors to optimize healing. The aim of this continuing medical education article is to provide an update on the management of venous leg ulcers. Part I is focused on the approach to venous ulcer diagnostic testing.

  12. The comparison of cold-water immersion and cold air therapy on maximal cycling performance and recovery markers following strength exercises

    PubMed Central

    Hayter, Kane J.; Schumann, Moritz; Deakin, Glen B.

    2016-01-01

    This study examined the effects of cold-water immersion (CWI) and cold air therapy (CAT) on maximal cycling performance (i.e. anaerobic power) and markers of muscle damage following a strength training session. Twenty endurance-trained but strength-untrained male (n = 10) and female (n = 10) participants were randomised into either: CWI (15 min in 14 °C water to iliac crest) or CAT (15 min in 14 °C air) immediately following strength training (i.e. 3 sets of leg press, leg extensions and leg curls at 6 repetition maximum, respectively). Creatine kinase, muscle soreness and fatigue, isometric knee extensor and flexor torque and cycling anaerobic power were measured prior to, immediately after and at 24 (T24), 48 (T48) and 72 (T72) h post-strength exercises. No significant differences were found between treatments for any of the measured variables (p > 0.05). However, trends suggested recovery was greater in CWI than CAT for cycling anaerobic power at T24 (10% ± 2%, ES = 0.90), T48 (8% ± 2%, ES = 0.64) and T72 (8% ± 7%, ES = 0.76). The findings suggest the combination of hydrostatic pressure and cold temperature may be favourable for recovery from strength training rather than cold temperature alone. PMID:27069791

  13. Exercise in the Cold

    PubMed Central

    Fudge, Jessie

    2016-01-01

    Context: Hypothermia and frostbite injuries occur in cold weather activities and sporting events. Evidence Acquisition: A PubMed search was used to identify original research and review articles related to cold, frostbite, and hypothermia. Inclusion was based on their relevance to prevention and treatment of cold-related injuries in sports and outdoor activities. Dates of review articles were limited to those published after 2010. No date limit was set for the most recent consensus statements or original research. Study Design: Clinical review. Level of Evidence: Level 5. Results: Frostbite and hypothermia are well-documented entities with good prevention strategies and prehospital treatment recommendations that have changed very little with time. A layered approach to clothing is the best way to prevent injury and respond to weather changes. Each athlete, defined as a participant in a cold weather sport or activity, will respond to cold differently depending on anthropometric measurements and underlying medical risk factors. An understanding of wind-chill temperatures, wetness, and the weather forecast allows athletes and event coordinators to properly respond to changing weather conditions. At the first sign of a freezing cold injury, ensure warm, dry clothes and move to a protected environment. Conclusion: Cold injuries can be prevented, and cold weather activities are safe with proper education, preparation, and response to changing weather conditions or injury. PMID:26857732

  14. Cold fusion research

    SciTech Connect

    1989-11-01

    I am pleased to forward to you the Final Report of the Cold Fusion Panel. This report reviews the current status of cold fusion and includes major chapters on Calorimetry and Excess Heat, Fusion Products and Materials Characterization. In addition, the report makes a number of conclusions and recommendations, as requested by the Secretary of Energy.

  15. Cold-Weather Sports

    MedlinePlus

    ... Surgery? A Week of Healthy Breakfasts Shyness Cold-Weather Sports KidsHealth > For Teens > Cold-Weather Sports Print A A A What's in this ... Equipment Ahh, winter! Shorter days. Frigid temperatures. Foul weather. What better time to be outdoors? Winter sports ...

  16. Cold Sores (HSV-1)

    MedlinePlus

    ... A Week of Healthy Breakfasts Shyness Cold Sores (HSV-1) KidsHealth > For Teens > Cold Sores (HSV-1) A A A What's in this article? ... or around a person's lips, are caused by herpes simplex virus-1 (HSV-1) . But they don't ...

  17. Chilling Out With Colds

    MedlinePlus

    ... Your head hurts. You don't have the energy to even get out of bed. And you can't breathe out of your nose. What's wrong? You may have a cold! Having a cold is the #1 reason kids visit the doctor and stay home from school. Kids can get six to ten ...

  18. Temperature dependence of the thermoelectric inhomogeneity for type B thermocouples from 180 °C to 960 °C

    NASA Astrophysics Data System (ADS)

    Kim, Yong-Gyoo; Lee, Young Hee; Joung, Wukchul

    2017-04-01

    For noble metal thermocouples, thermoelectric inhomogeneity is the most important factor of the calibration uncertainty. For type R and S thermocouples, it is possible to perform a scan at low temperature of around 200 °C, and extrapolate the calculated inhomogeneity to a higher temperature range. However, there has been little experimental study on the thermoelectric scan of type B thermocouples covering low temperature to high temperature of about 1000 °C. In order to determine the practical temperature dependence of the inhomogeneity of type B thermocouples, two used thermocouples were selected and tested from 180 °C to 960 °C based on the single temperature gradient immersion technique. Two liquid baths, one a silicon oil bath at 180 °C and the other a salt bath at 400 °C, were used, and a sodium-heat pipe furnace was used above 600 °C with intervals of around 120 °C. The tested thermocouples generated large emf variations with the immersion depth, and the amount of the variation increased with the test temperature. The calculated inhomogeneity showed the largest value at the lowest temperature, and decreased gradually with increasing temperature to 600 °C. Above this temperature, the inhomogeneity was nearly constant with temperature change, indicating that it was possible to extrapolate the uncertainty due to the inhomogeneity at 600 °C to higher temperatures. From the measured results, it was recommended that a thermoelectric scan be performed at a temperature of at least 600 °C using the sodium-heat pipe furnace to obtain a small calibration uncertainty of a type B thermocouple.

  19. Study of Thermocurrents in ILC cavities via measurements of the Seebeck Effect in niobium, titanium, and stainless steel thermocouples

    SciTech Connect

    Cooley, Victoria

    2014-01-01

    The goals of Fermilab’s Superconductivity and Radio Frequency Development Department are to engineer, fabricate, and improve superconducting radio frequency (SCRF) cavities in the interest of advancing accelerator technology. Improvement includes exploring possible limitations on cavity performance and mitigating such impediments. This report focuses on investigating and measuring the Seebeck Effect observed in cavity constituents titanium, niobium, and stainless steel arranged in thermocouples. These junctions exist between cavities, helium jackets, and bellows, and their connection can produce a loop of electrical current and magnetic flux spontaneously during cooling. The experimental procedure and results are described and analyzed. Implications relating the results to cavity performance are discussed.

  20. Attachment of lead wires to thin film thermocouples mounted on high temperature materials using the parallel gap welding process

    NASA Technical Reports Server (NTRS)

    Holanda, Raymond; Kim, Walter S.; Pencil, Eric; Groth, Mary; Danzey, Gerald A.

    1990-01-01

    Parallel gap resistance welding was used to attach lead wires to sputtered thin film sensors. Ranges of optimum welding parameters to produce an acceptable weld were determined. The thin film sensors were Pt13Rh/Pt thermocouples; they were mounted on substrates of MCrAlY-coated superalloys, aluminum oxide, silicon carbide and silicon nitride. The entire sensor system is designed to be used on aircraft engine parts. These sensor systems, including the thin-film-to-lead-wire connectors, were tested to 1000 C.

  1. Evaluation of the self-calibrating thermocouple as a front end to a smart temperature measurement system

    SciTech Connect

    Ruppel, F.R.

    1991-01-01

    An evaluation of the novel self-calibrating thermocouple was performed to determine whether the sensor would be acceptable as a front end to a smart temperature measurement system. The evaluation consisted of a fast-ramp test, long-term drift tests, and physical examinations including X rays, microphotography, and energy-dispersive spectrometry. The results of the tests show that the sensor is a viable industrial-grade device worthy for use in this application. However, recommendations for improving fabrication of the assembly are made and caveats are given for conditions that may constrain the use of the sensor in certain situations. 4 refs., 17 figs., 1 tab.

  2. Scanning thermal microscopy based on a quartz tuning fork and a micro-thermocouple in active mode (2ω method).

    PubMed

    Bontempi, Alexia; Nguyen, Tran Phong; Salut, Roland; Thiery, Laurent; Teyssieux, Damien; Vairac, Pascal

    2016-06-01

    A novel probe for scanning thermal microscope using a micro-thermocouple probe placed on a Quartz Tuning Fork (QTF) is presented. Instead of using an external deflection with a cantilever beam for contact detection, an original combination of piezoelectric resonator and thermal probe is employed. Due to a non-contact photothermal excitation principle, the high quality factor of the QTF allows the probe-to-surface contact detection. Topographic and thermal scanning images obtained on a specific sample points out the interest of our system as an alternative to cantilevered resistive probe systems which are the most spread.

  3. Uncooled antenna-coupled terahertz detectors with 22 μs response time based on BiSb/Sb thermocouples

    NASA Astrophysics Data System (ADS)

    Huhn, Anna K.; Spickermann, Gunnar; Ihring, Andreas; Schinkel, Uwe; Meyer, Hans-Georg; Haring Bolívar, Peter

    2013-03-01

    We report on fast terahertz detectors based on antenna-coupled BiSb/Sb thermoelements operating at room temperature. A response time of the thermocouples as low as 22 μs and a noise equivalent power of 170 pW/√Hz at 1 kHz modulation frequency is measured in air at room temperature. The integration capability of these mass producible devices enables large-scale detector arrays for real-time terahertz imaging applications. Due to the fast response time, multiplexing of the detectors can be used to reduce the required readout circuits.

  4. Profile of altered brain iron acquisition in restless legs syndrome.

    PubMed

    Connor, James R; Ponnuru, Padmavathi; Wang, Xin-Sheng; Patton, Stephanie M; Allen, Richard P; Earley, Christopher J

    2011-04-01

    Restless legs syndrome is a neurological disorder characterized by an urgency to move the legs during periods of rest. Data from a variety of sources provide a compelling argument that the amount of iron in the brain is lower in individuals with restless legs syndrome compared with neurologically normal individuals. Moreover, a significant percentage of patients with restless legs syndrome are responsive to intravenous iron therapy. The mechanism underlying the decreased iron concentrations in restless legs syndrome brains is unknown. We hypothesize that the source of the brain iron deficit is at the blood-brain interface. Thus we analysed the expression of iron management proteins in the epithelial cells of the choroid plexus and the brain microvasculature in post-mortem tissues. The choroid plexus, obtained at autopsy, from 18 neurologically normal controls and 14 individuals who had primary restless legs syndrome was subjected to histochemical staining for iron and immunostaining for iron management proteins. Iron and heavy chain ferritin staining was reduced in the epithelial cells of choroid plexus in restless legs syndrome. Divalent metal transporter, ferroportin, transferrin and its receptor were upregulated in the choroid plexus in restless legs syndrome. Microvessels were isolated from the motor cortex of 11 restless legs syndrome and 14 control brains obtained at autopsy and quantitative immunoblot analyses was performed. Expression of heavy chain ferritin, transferrin and its receptor in the microvessels from restless legs syndrome was significantly decreased compared with the controls but divalent metal protein 1, ferroportin, prohepcidin, mitochondrial ferritin and light-chain ferritin remained unchanged. The presence of an iron regulatory protein was demonstrated in the brain microvasculature and the activity of this protein is decreased in restless legs syndrome; a finding similar to our earlier report in neuromelanin cells from the substantia nigra

  5. Actigraphic assessment of periodic leg movements in patients with restless legs syndrome.

    PubMed

    Cippà, Maria A T; Baumann, Christian R; Siccoli, Massimiliano M; Bassetti, Claudio L; Poryazova, Rositsa; Werth, Esther

    2013-10-01

    The diagnosis of restless legs syndrome (RLS) relies upon diagnostic criteria which are based on history only, and dopaminergic treatment is not normally the first choice of treatment for all patients. It would be worthwhile to identify patients non-responsive to dopaminergic treatment beforehand, because they may suffer from a restless legs-like syndrome and may require alternative treatment. We included retrospectively 24 adult patients fulfilling the four essential criteria for restless legs and 12 age-matched healthy controls. They were investigated by ambulatory actigraphy from both legs over three nights, and patients started treatment with dopamine agonists after this diagnostic work-up. We examined 12 responders to dopaminergic treatment and 12 non-responders and studied the association between response to dopaminergic treatment and the periodic limb movement index (PLMI) as assessed with actigraphy. Demographic characteristics, excessive daytime sleepiness and fatigue at baseline were similar in all three groups. Baseline RLS severity was similar between responders and non-responders [International Restless Legs Severity Scale (IRLS): 25 ± 9 and 24 ± 8]. Group comparisons of PLMI before treatment initiation showed significant differences between the three groups. Post-hoc pairwise comparisons revealed that healthy controls had significantly lower PLMI (4.9 ± 4.5) than responders (29.3 ± 22.7) and non-responders (13.3 ± 11.2). Similarly, the PLMI in responders was lower than in non-responders. PLMI day-to-day variability did not differ between responders and non-responders and there was no correlation between treatment effect, as assessed by the decrease of the IRLS and baseline PLMI. Our retrospective study indicates that actigraphy to assess periodic limb movements may contribute to a better diagnosis of dopamine-responsive restless legs syndrome.

  6. On the Biomimetic Design of Agile-Robot Legs

    PubMed Central

    Garcia, Elena; Arevalo, Juan Carlos; Muñoz, Gustavo; Gonzalez-de-Santos, Pablo

    2011-01-01

    The development of functional legged robots has encountered its limits in human-made actuation technology. This paper describes research on the biomimetic design of legs for agile quadrupeds. A biomimetic leg concept that extracts key principles from horse legs which are responsible for the agile and powerful locomotion of these animals is presented. The proposed biomimetic leg model defines the effective leg length, leg kinematics, limb mass distribution, actuator power, and elastic energy recovery as determinants of agile locomotion, and values for these five key elements are given. The transfer of the extracted principles to technological instantiations is analyzed in detail, considering the availability of current materials, structures and actuators. A real leg prototype has been developed following the biomimetic leg concept proposed. The actuation system is based on the hybrid use of series elasticity and magneto-rheological dampers which provides variable compliance for natural motion. From the experimental evaluation of this prototype, conclusions on the current technological barriers to achieve real functional legged robots to walk dynamically in agile locomotion are presented. PMID:22247667

  7. The natural shock absorption of the leg spring.

    PubMed

    Kim, Wangdo; João, Filipa; Tan, John; Mota, Patricia; Vleck, Veronica; Aguiar, Liliana; Veloso, Antonio

    2013-01-04

    When a human being runs, muscles, tendons, and ligaments together behave like a single linear spring. This "leg spring" can be described remarkably well by spring/mass models. Although leg-stiffness during running (and logically, therefore, in hopping) has been shown to be adjusted in line with the individual characteristics of the external contact surface, the relative contribution of each of the sub-components of the leg spring to the mechanics of running is unclear. We proposed the three-degree-of-freedom leg spring chain in a position of stable equilibrium under the action of the leg stiffness. If the leg spring receives a displacement in hopping, the forces will no longer equilibrate, but the system will be exposed to the action of a force on a leg spring chain. We thus have two corresponding sets of modes, one set being the mode about which the chain is displaced, the other set for the forces which are evoked in consequence of the displacement. We found that if the leg has been displaced from a position of equilibrium about one of harmonic modes, then a vibration about this harmonic mode evokes a system of forces in the leg spring which in its turn tends to produce a motion on the original harmonic mode, and thus produce oscillation about the same harmonic mode. Our results suggest that the desired harmonic mode can be explained in terms of the natural shock absorption ability of the leg.

  8. Leg stiffness of sprinters using running-specific prostheses.

    PubMed

    McGowan, Craig P; Grabowski, Alena M; McDermott, William J; Herr, Hugh M; Kram, Rodger

    2012-08-07

    Running-specific prostheses (RSF) are designed to replicate the spring-like nature of biological legs (bioL) during running. However, it is not clear how these devices affect whole leg stiffness characteristics or running dynamics over a range of speeds. We used a simple spring-mass model to examine running mechanics across a range of speeds, in unilateral and bilateral transtibial amputees and performance-matched controls. We found significant differences between the affected leg (AL) of unilateral amputees and both ALs of bilateral amputees compared with the bioL of non-amputees for nearly every variable measured. Leg stiffness remained constant or increased with speed in bioL, but decreased with speed in legs with RSPs. The decrease in leg stiffness in legs with RSPs was mainly owing to a combination of lower peak ground reaction forces and increased leg compression with increasing speeds. Leg stiffness is an important parameter affecting contact time and the force exerted on the ground. It is likely that the fixed stiffness of the prosthesis coupled with differences in the limb posture required to run with the prosthesis limits the ability to modulate whole leg stiffness and the ability to apply high vertical ground reaction forces during sprinting.

  9. On the biomimetic design of agile-robot legs.

    PubMed

    Garcia, Elena; Arevalo, Juan Carlos; Muñoz, Gustavo; Gonzalez-de-Santos, Pablo

    2011-01-01

    The development of functional legged robots has encountered its limits in human-made actuation technology. This paper describes research on the biomimetic design of legs for agile quadrupeds. A biomimetic leg concept that extracts key principles from horse legs which are responsible for the agile and powerful locomotion of these animals is presented. The proposed biomimetic leg model defines the effective leg length, leg kinematics, limb mass distribution, actuator power, and elastic energy recovery as determinants of agile locomotion, and values for these five key elements are given. The transfer of the extracted principles to technological instantiations is analyzed in detail, considering the availability of current materials, structures and actuators. A real leg prototype has been developed following the biomimetic leg concept proposed. The actuation system is based on the hybrid use of series elasticity and magneto-rheological dampers which provides variable compliance for natural motion. From the experimental evaluation of this prototype, conclusions on the current technological barriers to achieve real functional legged robots to walk dynamically in agile locomotion are presented.

  10. Relationship between Leg Mass, Leg Composition and Foot Velocity on Kicking Accuracy in Australian Football

    PubMed Central

    Hart, Nicolas H.; Nimphius, Sophia; Spiteri, Tania; Cochrane, Jodie L.; Newton, Robert U.

    2016-01-01

    Kicking a ball accurately over a desired distance to an intended target is arguably the most important skill to acquire in Australian Football. Therefore, understanding the potential mechanisms which underpin kicking accuracy is warranted. The aim of this study was to examine the relationship between leg mass, leg composition and foot velocity on kicking accuracy in Australian Football. Thirty-one Australian Footballers (n = 31; age: 22.1 ± 2.8 years; height: 1.81 ± 0.07 m; weight: 85.1 ± 13.0 kg; BMI: 25.9 ± 3.2) each performed ten drop punt kicks over twenty metres to a player target. Athletes were separated into accurate (n = 15) and inaccurate (n = 16) kicking groups. Leg mass characteristics were assessed using whole body DXA scans. Foot velocity was determined using a ten-camera optoelectronic, three-dimensional motion capture system. Interactions between leg mass and foot velocity evident within accurate kickers only (r = -0.670 to -0.701). Relative lean mass was positively correlated with kicking accuracy (r = 0.631), while no relationship between foot velocity and kicking accuracy was evident in isolation (r = -0.047 to -0.083). Given the evident importance of lean mass, and its interaction with foot velocity for accurate kickers; future research should explore speed-accuracy, impulse-variability, limb co-ordination and foot-ball interaction constructs in kicking using controlled with-in subject studies to examine the effects of resistance training and skill acquisition programs on the development of kicking accuracy. Key points Accurate kickers expressed a very strong inverse relationship between leg mass and foot velocity. Inaccurate kickers were unable to replicate this, with greater volatility in their performance, indicating an ability of accurate kickers to mediate foot velocity to compensate for leg mass in order to deliver the ball over the required distance. Accurate kickers exhibited larger quantities of relative lean mass and lower

  11. Relationship between Leg Mass, Leg Composition and Foot Velocity on Kicking Accuracy in Australian Football.

    PubMed

    Hart, Nicolas H; Nimphius, Sophia; Spiteri, Tania; Cochrane, Jodie L; Newton, Robert U

    2016-06-01

    Kicking a ball accurately over a desired distance to an intended target is arguably the most important skill to acquire in Australian Football. Therefore, understanding the potential mechanisms which underpin kicking accuracy is warranted. The aim of this study was to examine the relationship between leg mass, leg composition and foot velocity on kicking accuracy in Australian Football. Thirty-one Australian Footballers (n = 31; age: 22.1 ± 2.8 years; height: 1.81 ± 0.07 m; weight: 85.1 ± 13.0 kg; BMI: 25.9 ± 3.2) each performed ten drop punt kicks over twenty metres to a player target. Athletes were separated into accurate (n = 15) and inaccurate (n = 16) kicking groups. Leg mass characteristics were assessed using whole body DXA scans. Foot velocity was determined using a ten-camera optoelectronic, three-dimensional motion capture system. Interactions between leg mass and foot velocity evident within accurate kickers only (r = -0.670 to -0.701). Relative lean mass was positively correlated with kicking accuracy (r = 0.631), while no relationship between foot velocity and kicking accuracy was evident in isolation (r = -0.047 to -0.083). Given the evident importance of lean mass, and its interaction with foot velocity for accurate kickers; future research should explore speed-accuracy, impulse-variability, limb co-ordination and foot-ball interaction constructs in kicking using controlled with-in subject studies to examine the effects of resistance training and skill acquisition programs on the development of kicking accuracy. Key pointsAccurate kickers expressed a very strong inverse relationship between leg mass and foot velocity. Inaccurate kickers were unable to replicate this, with greater volatility in their performance, indicating an ability of accurate kickers to mediate foot velocity to compensate for leg mass in order to deliver the ball over the required distance.Accurate kickers exhibited larger quantities of relative lean mass and lower quantities

  12. [Bow legged adjectives in ancient literature].

    PubMed

    Simon, Frantisek; Steger, Florian

    2011-01-01

    This article addresses the issue of capturing the medical entity called 'curved legs' in a terminologically exact way. In so doing, it refers to the long-lasting process of differentiation of exact nuances of meaning in Ancient Greek and Latin. In the chronological perusal of ancient Greek literature, it becomes evident that the various adjectives employed are often vague when looking at non-medical literature. By contrast, in the Hippocratic corpus these terms are for the first time annotated with explanations intended to lead to a more precise understanding of the described deformity. Further attempts of differentiation can be found in the writings of Galen, who not only distinguishes between outward and inward curvatures, but also between deformities of the thigh and lower leg as well as between pathological and natural curvatures. Latin literature also provides a series of adjectives that were initially often used in the meaning of 'curved' but it was not until Celsus that these were differentiated with respect to the type and direction of the curvature. When comparing Greek and Latin adjectives, it turns out that though the Latin term blaesus can be traced back etymologically to the Greek word beta lambda alpha iota sigma ó zeta, the meaning of beta lambda alpha iota sigma ó zeta does not fully correspond to that of the Latin word. It is not before the later common transliteration of Greek words that this adjective took on the meaning of beta lambda alpha iota sigma ó zeta; however, this was finally lost again. In summary, the article concludes that exact word meanings in ancient literature are often unclear and precise ascriptions of meanings are inconsistent. In the case of "curved legs," this has led to misunderstandings regarding the respective types and directions of the curvature.

  13. Cold subcutaneous abscesses.

    PubMed Central

    Jackson, R.; Stephens, L.; Kelly, A. P.

    1990-01-01

    Cold abscesses are defined as having no associated erythema, heat, or tenderness. They may be present in immunodeficiency disorders, deep mycoses, and other infectious diseases. As there is a dearth information on this subject in the dermatology, surgery, and infectious disease literature, we present a case of cold abscesses secondary to coccidioidomycosis and discuss the possible role of humoral immunity, cell-mediated immunity, prostaglandins, T cells, and other mediators in cold abscess pathogenesis. In addition, therapeutic guidelines for abscesses are reviewed. Images Figure 1 Figure 2 PMID:2280425

  14. Miniature cold gas thrusters

    NASA Astrophysics Data System (ADS)

    Bzibziak, R. J., Sr.

    1992-07-01

    Cold gas thrusters provide a safe, inexpensive, lightweight and reliable means of propulsive control for small satellites, projectiles and maneuvering control systems. Moog Inc. has designed and developed a family of miniature cold gas thrusters for use on Strategic Defense Iniative flight simulation experiments, sounding rockets, small satellite applications, astronaut control systems, and close proximity maneuvering systems for Space System. Construction features such as coil assembly, core assembly, armature assembly, external housing and valve body are discussed. The design approach, performance characteristics and functional description of cold gas thrusters designed for various applications are presented.

  15. Transcutaneous laser treatment of leg veins.

    PubMed

    Meesters, Arne A; Pitassi, Luiza H U; Campos, Valeria; Wolkerstorfer, Albert; Dierickx, Christine C

    2014-03-01

    Leg telangiectasias and reticular veins are a common complaint affecting more than 80% of the population to some extent. To date, the gold standard remains sclerotherapy for most patients. However, there may be some specific situations, where sclerotherapy is contraindicated such as needle phobia, allergy to certain sclerosing agents, and the presence of vessels smaller than the diameter of a 30-gauge needle (including telangiectatic matting). In these cases, transcutaneous laser therapy is a valuable alternative. Currently, different laser modalities have been proposed for the management of leg veins. The aim of this article is to present an overview of the basic principles of transcutaneous laser therapy of leg veins and to review the existing literature on this subject, including the most recent developments. The 532-nm potassium titanyl phosphate (KTP) laser, the 585-600-nm pulsed dye laser, the 755-nm alexandrite laser, various 800-983-nm diode lasers, and the 1,064-nm neodymium yttrium-aluminum-garnet (Nd:YAG) laser and various intense pulsed light sources have been investigated for this indication. The KTP and pulsed dye laser are an effective treatment option for small vessels (<1 mm). The side effect profile is usually favorable to that of longer wavelength modalities. For larger veins, the use of a longer wavelength is required. According to the scarce evidence available, the Nd:YAG laser produces better clinical results than the alexandrite and diode laser. Penetration depth is high, whereas absorption by melanin is low, making the Nd:YAG laser suitable for the treatment of larger and deeply located veins and for the treatment of patients with dark skin types. Clinical outcome of Nd:YAG laser therapy approximates that of sclerotherapy, although the latter is associated with less pain. New developments include (1) the use of a nonuniform pulse sequence or a dual-wavelength modality, inducing methemoglobin formation and enhancing the optical absorption

  16. Refractory leg ulcers associated with Klinefelter syndrome.

    PubMed

    Yabuno, Yuto; Tosa, Mamiko; Iwakiri, Itaru; Nomoto, Shunichi; Kaneko, Mayuko; Kuwahara, Kousuke; Hyakusoku, Hiko; Murakami, Masahiro

    2015-01-01

    We present a man with refractory leg ulcers, bilateral varicosis of the lower extremities, and Buerger disease. Autoimmune work-up was negative. However, chromosome analysis showed Klinefelter syndrome (48 XXY). Ulcerative lesions of the lower extremities are a complication of Klinefelter syndrome. To date, the pathogenesis of ulcers in Klinefelter syndrome has not been clarified, but several factors, such as abnormalities of fibrinolysis and prothrombotic states, might be involved. Our present case emphasizes the importance of considering Klinefelter syndrome in the differential diagnosis of a male patient with nonhealing ulcers of the lower extremities.

  17. Leg ulcer in lepromatous leprosy - Case report*

    PubMed Central

    Fernandes, Tania Rita Moreno de Oliveira; dos Santos, Talita Suzany Siqueira; Lopes, Ramon Rodrigues de Macedo

    2016-01-01

    In Brazil, leprosy is a widespread infectious and contagious disease. Clinicians and specialists view leprosy broadly as a systemic infection, since, in its manifestations, it mimics many conditions, such as rheumatic, vascular, ENT, neurological and dermatological diseases. There are few studies that characterize the factors associated with ulcers in leprosy. These injuries should be prevented and treated promptly to avoid serious problems like secondary infections, sepsis, carcinomatous degeneration and amputations. We describe a patient with ulcers on his legs, involving late diagnosis of lepromatous leprosy. PMID:27828650

  18. Is leg compression beneficial for alpine skiers?

    PubMed Central

    2013-01-01

    Background This study examined the effects of different levels of compression (0, 20 and 40 mmHg) produced by leg garments on selected psycho-physiological measures of performance while exposed to passive vibration (60 Hz, amplitude 4-6 mm) and performing 3-min of alpine skiing tuck position. Methods Prior to, during and following the experiment the electromygraphic (EMG) activity of different muscles, cardio-respiratory data, changes in total hemoglobin, tissue oxygenation and oscillatory movement of m. vastus lateralis, blood lactate and perceptual data of 12 highly trained alpine skiers were recorded. Maximal isometric knee extension and flexion strength, balance, and jumping performance were assessed before and after the experiment. Results The knee angle (−10°) and oscillatory movement (−20-25.5%) were lower with compression (P < 0.05 in all cases). The EMG activities of the tibialis anterior (20.2-28.9%), gastrocnemius medialis (4.9-15.1%), rectus femoris (9.6-23.5%), and vastus medialis (13.1-13.7%) muscles were all elevated by compression (P < 0.05 in all cases). Total hemoglobin was maintained during the 3-min period of simulated skiing with 20 or 40 mmHg compression, but the tissue saturation index was lower (P < 0.05) than with no compression. No differences in respiratory parameters, heart rate or blood lactate concentration were observed with or maximal isometric knee extension and flexion strength, balance, and jumping performance following simulated skiing for 3 min in the downhill tuck position were the same as in the absence of compression. Conclusions These findings demonstrate that with leg compression, alpine skiers could maintain a deeper tuck position with less perceived exertion and greater deoxygenation of the vastus lateralis muscle, with no differences in whole-body oxygen consumption or blood lactate concentration. These changes occurred without compromising maximal leg strength, jumping performance or balance

  19. Effect of local cold application on glycogen recovery.

    PubMed

    Tucker, T J; Slivka, D R; Cuddy, J S; Hailes, W S; Ruby, B C

    2012-04-01

    The purpose of this study was to investigate the effect of local cold application on muscle glycogen re-synthesis after exercise. Recreationally active male subjects (n=11) completed a 90-minute glycogen depleting ride, followed by 4 h of recovery. During recovery, ice was applied intermittently to one leg (IL) while the subjects other leg (CL) acted as a control. Intramuscular and rectal temperature was recorded continuously. A carbohydrate (1.8 g∙kg-1 bodyweight) beverage was supplied at 0 and 2 h post exercise. Muscle biopsies were taken immediately after exercise from the vastus lateralis and at 4 h post exercise for the analysis of muscle glycogen and muscle lactate. Leg circumference was measured 30, 60, 120, 180, and 240 minutes into recovery. The IL was colder than the CL from 15 minutes after initial ice application until the end recovery (P<0.05). Immediate post-exercise glycogen was similar between legs (55.3±7.4 vs. 56.1±7 mmol∙kg-1 wet weight for the iced vs. control, respectively). However, muscle glycogen was lower in the IL compared to the CL at 4 h post exercise (72±8.4 vs. 95±8.4 mmol∙kg-1 wet weight, respectively; P<0.05). Muscle lactate was lower in the IL after 4 h of recovery compared to the CL (1.6±.2 vs. 2.6±.2 mmol∙L-1, respectively; P<0.05). There was no difference in circumference between IL and CL. These data demonstrate a reduction in muscle glycogen re-synthesis with local cold application.

  20. Effect of the fissile bead's and thermocouple wires’ sizes on the response time of a fission couple

    SciTech Connect

    Liang, Wenfeng Lu, Yi; Li, Meng; Fan, Xiaoqiang; Lu, Wei

    2014-05-15

    The fission couple is proposed as a fast response miniature neutron detector in the measurement of time dependent energy depositions within the fissile material based on theoretical analysis, but the response time of a fission couple is relatively slow in practice. The time lag originated from heat transfer process was demonstrated to be the dominating factor by theoretical simulations and experimental verification in this paper. The response of a fission couple as a function of the bead size and the thermocouple wires’ sizes are simulated using ANSYS workbench. The decrease of wires’ diameter results in the decrease of response time, and the increase of bead's diameter leads to a slight increase of response time. During a pulse heating transient in the fuel of Chinese Fast Burst Reactor II with a FWHM of 181μs, the time lag originated from heat transfer process is about tens of microseconds for the peaks of the change rate of temperature, and is of the order of milliseconds to achieve 85% of the temperature rise for a typical fission couple with a Φ 1 mm fissile bead and two Φ 0.05 mm thermocouple wires. The results obtained provide foundation for the optimization of fission couples.

  1. Effect of the fissile bead's and thermocouple wires' sizes on the response time of a fission couple.

    PubMed

    Liang, Wenfeng; Lu, Yi; Li, Meng; Fan, Xiaoqiang; Lu, Wei

    2014-05-01

    The fission couple is proposed as a fast response miniature neutron detector in the measurement of time dependent energy depositions within the fissile material based on theoretical analysis, but the response time of a fission couple is relatively slow in practice. The time lag originated from heat transfer process was demonstrated to be the dominating factor by theoretical simulations and experimental verification in this paper. The response of a fission couple as a function of the bead size and the thermocouple wires' sizes are simulated using ANSYS workbench. The decrease of wires' diameter results in the decrease of response time, and the increase of bead's diameter leads to a slight increase of response time. During a pulse heating transient in the fuel of Chinese Fast Burst Reactor II with a FWHM of 181 μs, the time lag originated from heat transfer process is about tens of microseconds for the peaks of the change rate of temperature, and is of the order of milliseconds to achieve 85% of the temperature rise for a typical fission couple with a Φ 1 mm fissile bead and two Φ 0.05 mm thermocouple wires. The results obtained provide foundation for the optimization of fission couples.

  2. Comparisons of Co-C and Pd-C Eutectic-Point Cells for Thermocouple Calibration Between NMIA and NMIJ

    NASA Astrophysics Data System (ADS)

    Ogura, H.; Jahan, F.; Yamazawa, K.

    2017-02-01

    Comparisons between NMIA and NMIJ on the melting temperatures of the Co-C eutectic point and the Pd-C eutectic point were performed using an NMIJ high-temperature furnace. The eutectic-point cells were constructed by NMIA and NMIJ following two different specifications. NMIA designed two miniature crucibles, one for Co-C and one for Pd-C eutectic-point cells. NMIJ designed larger eutectic-point cells, one for Co-C and one for Pd-C eutectic-point cells. Prior to performing the comparisons, the effect of conductive heat flow through the thermocouple stem was evaluated during the melting. The comparisons of the Co-C eutectic-point cells and of the Pd-C eutectic-point cells were performed using types R, B and Pt/Pd thermocouples. Despite the different cell designs and different material sources, the melting temperatures of the Co-C and Pd-C eutectic-point cells under investigation agreed within 0.1°C.

  3. Initial characterization of the Cornell Cold Neutron Source

    NASA Astrophysics Data System (ADS)

    Spern, Stuart Alan

    1998-06-01

    A device to moderate reactor spectrum neutrons to subthermal energies and filter out photons and higher energy neutrons has been designed, constructed and tested at Ward Laboratory, Cornell University. The Cornell Cold Neutron Source, which houses a chamber containing an organic moderator (mesitylene), the cryogenic cooling apparatus, and the first three one-meter long neutron guide elements, is physically inserted into a beamport in the reactor biological shield. The remaining 10 guide elements, which act as the filter, are mounted on a horizontal I-beam, and surrounded with suitable radiation shielding. The elements are horizontally displaced from the beamport axis in a combination curved/straight layout to eliminate directly transmitted radiation. The guide penetrates the reactor bay wall, terminating in a dedicated room to provide a location for low background experiments. Out-of-reactor bench thermal tests were conducted on the cryorefrigerator itself, then on a shortened version of the cryogenic cooling apparatus, and finally on the full scale system using heaters to simulate reactor induced nuclear heating in upstream cryogenic components. Temperature results, measured by silicon diodes, were close to predicted values. In-reactor tests were conducted to benchmark thermal performance, and to ascertain reliability of temperature and flux measurement systems. Type E thermocouples were selected for temperature measurement in the hostile reactor environment; although they depart from standard output at cryogenic temperatures due to inhomogeneities in the wire, crucial thermocouples located on the moderator chamber are calibrated against the in situ gas thermometer formed with the chamber as the sense bulb and a canister of known volume as the gas reservoir. In- reactor trials demonstrated reproducibility of thermocouple results. Moderator temperatures of 11 K at zero reactor power up to 28.5 K at 500 kW were obtained. Time-of-flight measurements were taken at 10

  4. Leg length discrepancy following irradiation for childhood tumors

    SciTech Connect

    Robertson, W.W. Jr.; Butler, M.S.; D'Angio, G.J.; Rate, W.R. )

    1991-05-01

    Leg length inequality developed in 12 of 67 children who were treated with radiation therapy to the kidney, abdomen, pelvis, or lower extremities. All these children survived childhood cancer to the age of skeletal maturity. Of the 12 with anisomelia, seven were symptomatic. There were significant relationships between the development of leg length inequality and the total dose of radiation to the pelvic area, asymmetric irradiation to the pelvis, and high-dose irradiation to the leg.

  5. Cold hardiness in molluscs

    NASA Astrophysics Data System (ADS)

    Ansart, Armelle; Vernon, Philippe

    2003-05-01

    Molluscs inhabit all types of environments: seawater, intertidal zone, freshwater and land, and of course may have to deal with subzero temperatures. Ectotherm animals survive cold conditions by avoiding it by extensive supercooling (freezing avoidant species) or by bearing the freezing of their extracellular body fluids (freezing tolerant species). Although some studies on cold hardiness are available for intertidal molluscs, they are scarce for freshwater and terrestrial ones. Molluscs often exhibit intermediary levels of cold hardiness, with a moderate or low ability to supercool and a limited survival to the freezing of their tissues. Several factors could be involved: their dependence on water, their ability to enter dormancy, the probability of inoculative freezing in their environment, etc. Size is an important parameter in the development of cold hardiness abilities: it influences supercooling ability in land snails, which are rather freezing avoidant and survival to ice formation in intertidal organisms, which generally tolerate freezing.

  6. Colds and flus - antibiotics

    MedlinePlus

    Fashner J, Ericson K, Werner S. Treatment of the common cold in children and adults. Am Fam Physician. 2012; ... gov/pubmed/22962927 . Melio FR, Berge LR. Upper respiratory tract infections. In: Marx JA, Hockberger RS, Walls RM, et ...

  7. Coping with Colds

    MedlinePlus

    ... re hungry. And you might have heard that chicken soup can cure a cold. There's no real ... you have strep throat and need treatment with antibiotics. If your doctor does prescribe antibiotics, be sure ...

  8. The cold reading technique.

    PubMed

    Dutton, D L

    1988-04-15

    For many people, belief in the paranormal derives from personal experience of face-to-face interviews with astrologers, palm readers, aura and Tarot readers, and spirit mediums. These encounters typically involve cold reading, a process in which a reader makes calculated guesses about a client's background and problems and, depending on the reaction, elaborates a reading which seems to the client so uniquely appropriate that it carries with it the illusion of having been produced by paranormal means. The cold reading process is shown to depend initially on the Barnum effect, the tendency for people to embrace generalized personality descriptions as idiosyncratically their own. Psychological research into the Barnum effect is critically reviewed, and uses of the effect by a professional magician are described. This is followed by detailed analysis of the cold reading performances of a spirit medium. Future research should investigate the degree to which cold readers may have convinced themselves that they actually possess psychic or paranormal abilities.

  9. Self-calibration of a W/Re thermocouple using a miniature Ru-C (1954 °C) eutectic cell

    SciTech Connect

    Ongrai, O.; Pearce, J. V.; Machin, G.; Sweeney, S. J.

    2013-09-11

    Previous successful investigations of miniature cobalt-carbon (Co-C, 1324 °C) and palladium-carbon (Pd-C, 1492 °C) high temperature fixed-point cells for thermocouple self-calibration have been reported [1-2]. In the present work, we describe a series of measurements of a miniature ruthenium-carbon (Ru-C) eutectic cell (melting point 1954 °C) to evaluate the repeatability and stability of a W/Re thermocouple (type C) by means of in-situ calibration. A miniature Ru-C eutectic fixed-point cell with outside diameter 14 mm and length 30 mm was fabricated to be used as a self-calibrating device. The performance of the miniature Ru-C cell and the type C thermocouple is presented, including characterization of the stability, repeatability, thermal environment influence, ITS-90 temperature realization and measurement uncertainty.

  10. Towards active capsular endoscopy: preliminary results on a legged platform.

    PubMed

    Menciassi, Arianna; Stefanini, Cesare; Orlandi, Giovanni; Quirini, Marco; Dario, Paolo

    2006-01-01

    This paper illustrates the problem of active locomotion in the gastrointestinal tract for endoscopic capsules. Authors analyze the problem of locomotion in unstructured, flexible and tubular environments and explain the reasons leading to the selection of a legged system. They present a theoretical simulation of legged capsule locomotion, which is used to define the optimal parameters for capsule design and gait selection. Finally, a legged capsule--about 3 cm3 in volume--is presented; it consists of 4 back legs whose actuation is achieved thanks to a miniaturized DC brushless motor. In vitro tests demonstrate good performance in terms of achievable speed (92 mm/min).

  11. Perception of imposed leg length inequality in normal subjects.

    PubMed

    O'Brien, Seamus; Kernohan, George; Fitzpatrick, Claire; Hill, Janet; Beverland, David

    2010-01-01

    Lower limb length differences of up to 10mm exist in 60% - 95% of the population.There are usually no symptoms or functional effects. Following Total Hip Arthroplasty (THA), satisfactory clinical results can be spoiled by dissatisfaction due to a change in leg length. Although the change in leg length may be modest in comparison to the normal variation, the patient may perceive this as a leg length discrepancy. To study the average threshold for perception, artificial leg length discrepancies of 5 mm to 25 mm were created in 30 young healthy adults using calibrated wooden blocks. Responses were recorded and analysed using a chi-squared test for independence and an independent measures t-test. Awareness of leg length discrepancy was related to the magnitude of the discrepancy (X2 (15)= 156.6, p<0.05 on the right side, and X2 (15)= 178.725 p<0.05 on the left side). It was shown that no subject reported a 5mm increase in leg length to be uncomfortable while all subjects were aware of leg length discrepancies of 20 mm and 25 mm. When there was a discrepancy of 10 mm in either lower limb, 29 out of 30 subjects (96.7%) thought there was a difference in leg length. Consequently it is suggested that during total hip arthroplasty the surgeon should aim for a leg length discrepancy of less than 10 mm.

  12. Hyperalgesia and functional sensory loss in restless legs syndrome.

    PubMed

    Stiasny-Kolster, Karin; Pfau, Doreen B; Oertel, Wolfgang H; Treede, Rolf-Detlef; Magerl, Walter

    2013-08-01

    Pain and other sensory signs in patients with restless legs syndrome (RLS) are still poorly understood, as most investigations focus on motor system dysfunctions. This study aimed to investigate somatosensory changes in patients with primary RLS and the restoration of somatosensory function by guideline-based treatment. Forty previously untreated RLS patients were investigated unilaterally over hand and foot using quantitative sensory testing (QST) and were compared with 40 age- and gender-matched healthy subjects. The predominant finding in RLS patients was 3- to 4-fold increase of sensitivity to pinprick stimuli in both extremities (hand: P<.05; foot: P<.001), a sensory pathway involved in withdrawal reflexes. Pinprick hyperalgesia was not paralleled by dynamic mechanical allodynia. Additional significant sensory changes were tactile hypoesthesia in both extremities (hand: P<.05; foot P<.01) and dysesthesia to non-noxious cold stimuli (paradoxical heat sensation), which was present in the foot in an unusually high proportion (14 of 40 patients; P<.01). In 8 patients, follow-up QST 2 to 20 months after treatment with l-DOPA (L-3,4-dihydroxyphenylalanine) revealed a significant reduction of pinprick hyperalgesia (-60%, P<.001), improved tactile detection (+50%, P<.05), and disappearance of paradoxical heat sensation in half of the patients. QST suggested a type of spinal or supraspinal central sensitization differing from neuropathic pain or human experimental models of central sensitization by the absence of dynamic mechanical allodynia. Reversal of pinprick hyperalgesia by l-DOPA may be explained by impaired descending inhibitory dopaminergic control on spinal nociceptive neurons. Restoration of tactile sensitivity and paradoxical heat sensations suggest that they were functional disturbances resulting from central disinhibition.

  13. A simple and inexpensive method for determining cold sensitivity and adaptation in mice.

    PubMed

    Brenner, Daniel S; Golden, Judith P; Vogt, Sherri K; Gereau, Robert W

    2015-03-17

    Cold hypersensitivity is a serious clinical problem, affecting a broad subset of patients and causing significant decreases in quality of life. The cold plantar assay allows the objective and inexpensive assessment of cold sensitivity in mice, and can quantify both analgesia and hypersensitivity. Mice are acclimated on a glass plate, and a compressed dry ice pellet is held against the glass surface underneath the hindpaw. The latency to withdrawal from the cooling glass is used as a measure of cold sensitivity. Cold sensation is also important for survival in regions with seasonal temperature shifts, and in order to maintain sensitivity animals must be able to adjust their thermal response thresholds to match the ambient temperature. The Cold Plantar Assay (CPA) also allows the study of adaptation to changes in ambient temperature by testing the cold sensitivity of mice at temperatures ranging from 30 °C to 5 °C. Mice are acclimated as described above, but the glass plate is cooled to the desired starting temperature using aluminum boxes (or aluminum foil packets) filled with hot water, wet ice, or dry ice. The temperature of the plate is measured at the center using a filament T-type thermocouple probe. Once the plate has reached the desired starting temperature, the animals are tested as described above. This assay allows testing of mice at temperatures ranging from innocuous to noxious. The CPA yields unambiguous and consistent behavioral responses in uninjured mice and can be used to quantify both hypersensitivity and analgesia. This protocol describes how to use the CPA to measure cold hypersensitivity, analgesia, and adaptation in mice.

  14. Olanzapine-induced restless legs syndrome.

    PubMed

    Zhao, Mangsuo; Geng, Tongchao; Qiao, Liyan; Zhang, Mingjie; Shi, Jie; Huang, Fangjie; Lin, Xianzhong; Wang, Jing; Zuo, Huancong

    2014-09-01

    Only nine patients with olanzapine-induced restless legs syndrome (RLS) have been reported in the literature to our knowledge. We describe two patients with olanzapine-induced RLS treated at our hospital and review the nine reported patients. There were five women and six men aged between 28 and 62 years in the overall group. RLS symptoms emerged at olanzapine doses between 2.5 and 20mg. The symptoms improved in all patients when the dose was reduced and immediately disappeared when the medication was stopped. International Restless Legs Scale (IRLS) scores ranged from 10 to 35. Three patients had a family history of idiopathic RLS. Supplemental drugs were administered to control RLS symptoms in five patients. Ropinirole was effective in one patient, while two patients did not respond to the drug. Propoxyphene effectively relieved symptoms in one patient who did not respond to ropinirole or clonazepam. RLS symptoms did not recur following substitution of other antipsychotic drugs for olanzapine. In conclusion, olanzapine can induce RLS, particularly in patients with a family history of idiopathic RLS. More than half of the patients experienced severe to very severe symptoms. A dose-dependent relationship was observed between olanzapine and RLS symptoms. A gradual increase in dose may prevent olanzapine-induced RLS. The optimal treatment for olanzapine-induced RLS is discontinuation of olanzapine.

  15. Intramedullary leg lengthening with a motorized nail

    PubMed Central

    2011-01-01

    Background and purpose In the last decade, intramedullary limb lengthening has become a viable alternative to traditional external systems. We retrospectively analyzed the use of an intramedullary motorized nail (Fitbone) in a consecutive series of 32 patients. Patients and methods During the period September 2006 to December 2008, 32 consecutive patients with a median age of 17 (IQR: 15–19) years were treated with a fully implantable, motorized intramedullary lengthening device (Fitbone). The median leg length discrepancy was 35 (IQR: 30–44) mm at the femur (n = 21) and 28 (IQR: 25–30) mm at the tibia (n = 11). Results Leg lengthening was successful in 30 of 32 cases, with no residual relevant discrepancy (± 5 mm). No intraoperative complications were observed. The consolidation index was significantly different (p = 0.04) between femoral lengthening (mean 35 days/cm) and tibial lengthening (mean 48 days/cm) but did not depend on age older/younger than 16 or previous operations at the affected site. 3 problems, 3 obstacles, and 4 complications (3 minor, 1 major) were encountered in 8 patients, 5 of which were implant-associated. Interpretation This technique even allows correction in patients with multiplanar deformities. Compared to external devices, intramedullary systems provide comfort and reduce complication rates, give improved cosmetic results, and lead to fast rehabilitation since percutaneous, transmuscular fixation is prevented. This results in reasonable overall treatment costs despite the relatively high costs of implants. PMID:21561309

  16. Immediate effects of the trunk stabilizing exercise on static balance parameters in double-leg and one-leg stances

    PubMed Central

    Kim, Jwa-jun; Park, Se-yeon

    2016-01-01

    [Purpose] The purpose of this study was to evaluate the immediate effect of stabilizing exercise using the PNF technique on standing balance in one-leg and double-leg stances. [Subjects and Methods] The present study recruited 34 healthy participants from a local university. The Participants performed four balance tests (double-leg stance with and without vision, one-leg stance with and without vision), before and after exercise. The exercise consisted of exercises performed using PNF techniques (stabilizing reversal and rhythmic stabilization), which were applied to facilitate trunk musculature. To examine balance ability, total displacement of the center of pressure was measured during balance tests. [Results] The total anterior–posterior center of pressure displacement was significantly reduced after applying rhythmic stabilization compared before exercise regardless of the balance test conditions. [Conclusion] The present results suggest that trunk stability exercise using rhythmic stabilization could effectively enhance balance ability under one-leg and double-leg conditions. PMID:27390392

  17. Final report on COOMET.T-S1. Comparison of type S thermocouples at the freezing points of zinc, aluminium and copper 2014—2015

    NASA Astrophysics Data System (ADS)

    Pokhodun, A. I.; Ivanova, A. G.; Duysebayeva, K. K.; Ivanova, K. P.

    2015-01-01

    Regional comparison of type S thermocouples at the freezing points of zinc, aluminium and copper was initiated by COOMET TC1.1-10 (the technical committee of COOMET `Thermometry and thermal physics'). Three NMI take part in COOMET regional comparison: D I Mendeleev Institute for Metrology (VNIIM) (Russian Federation), National Scientific Centre (Institute of Metrology) (NSC IM, Ukraine), Republic State Enterprise (Kazakhstan Institute of Metrology) (KazInMetr, Republic of Kazakhstan). VNIIM (Russia) was chosen as the coordinator-pilot of the regional comparison. A star type comparison was used. The participants: KazInMetr and NSC IM constructed the type S thermocouples and calibrated them in three fixed points: zinc, aluminum and copper points, using methods of ITS-90 fixed point realizations. The thermocouples have been sent to VNIIM together with the results of the calibration at three fixed points, with the values of the inhomogeneity at temperature 200 °C and the uncertainty evaluations of the results. For calibration of thermocouples the same VNIIM fixed points cells were used. Participating laboratories repeated the calibration of thermocouples after its returning in zinc, aluminum and copper points to determine the stability of its results. In result of the comparison was to evaluate the equivalence of the type S thermocouples calibration in fixed points by NMIs to confirm corresponding lines of international website for NMI's Calibration and Measurement Capabilities (CMC). This paper is the final report of the comparison including analysis of the uncertainty of measurement results. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCT WG-KC, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  18. Teaching in a Cold Environment.

    ERIC Educational Resources Information Center

    Ewert, Alan

    1979-01-01

    Designed to help teachers deal with students in a cold environment, this article explains cold physiology and fundamental laws of heat; describes 14 common cold injuries and their current treatment; and lists a number of useful teaching techniques for cold environments. (SB)

  19. Teaching in a Cold Environment.

    ERIC Educational Resources Information Center

    Ewert, Alan

    Instructors who teach outdoors in an environment so cold as to cause injury must satisfy program objectives while avoiding cold injury to themselves and students, help students focus on learning instead of discomfort, and alleviate some students' intense fear of the cold. Dealing with the cold successfully requires a thorough knowledge of:…

  20. Understanding Colds: Anatomy of the Nose

    MedlinePlus

    ... Colds Prevention Treatment Children Complications Special Features References Common Cold Understanding Colds Anatomy of the Nose The nose ... cm (3/8 inch) per minute. What a Common Cold Is A common cold is an illness caused ...

  1. Cold moderators at ORNL

    SciTech Connect

    Lucas, A. T.

    1997-09-01

    The Advanced Neutron Source (ANS) cold moderators were not an 'Oak Ridge first', but would have been the largest both physically and in terms of cold neutron flux. Two cold moderators were planned each 410 mm in diameter and containing about 30L of liquid deuterium. They were to be completely independent of each other. A modular system design was used to provide greater reliability and serviceability. When the ANS was terminated, up–grading of the resident High Flux Isotope Reactor (HFIR) was examined and an initial study was made into the feasibility of adding a cold source. Because the ANS design was modular, it was possible to use many identical design features. Sub-cooled liquid at 4 bar abs was initially chosen for the HFIR design concept, but this was subsequently changed to 15 bar abs to operate above the critical pressure. As in the ANS, the hydrogen will operate at a constant pressure throughout the temperature range and a completely closed loop with secondary containment was adopted. The heat load of 2 kW made the heat flux comparable with that of the ANS. Subsequent studies into the construction of cryogenic moderators for the proposed new Synchrotron Neutron source indicated that again many of the same design concepts could be used. By connecting the two cold sources together in series, the total heat load of 2 kW is very close to that of the HFIR allowing a very similar supercritical hydrogen system to be configured. The two hydrogen moderators of the SNS provide a comparable heat load to the HFIR moderator. It is subsequently planned to connect the two in series and operate from a single cold loop system, once again using supercritical hydrogen. The spallation source also provided an opportunity to re-examine a cold pellet solid methane moderator operating at 20K.

  2. The swollen leg and primary lymphoedema.

    PubMed Central

    Wright, N B; Carty, H M

    1994-01-01

    Children who present with unilateral or bilateral swelling of the legs are often suspected of having a deep venous thrombosis. The incidence of deep venous thrombosis in children is low and lymphoedema may be a more appropriate diagnosis. Lymphoedema can be primary or secondary. In childhood, primary lymphoedema is more common and may be seen associated with other congenital abnormalities, such as cardiac anomalies or gonadal dysgenesis. Primary hypoplastic lymphoedema is the most often encountered type. It is more common in girls, especially around puberty, and is typically painless. Atypical presentations produce diagnostic confusion and may require imaging to confirm the presence, extent, and precise anatomical nature of the lymphatic dysplasia. This article describes four patients presenting with limb pain and reviews the clinical features and imaging options in children with suspected lymphoedema. Images PMID:8067792

  3. Series Elastic Actuators for legged robots

    NASA Astrophysics Data System (ADS)

    Pratt, Jerry E.; Krupp, Benjamin T.

    2004-09-01

    Series Elastic Actuators provide many benefits in force control of robots in unconstrained environments. These benefits include high force fidelity, extremely low impedance, low friction, and good force control bandwidth. Series Elastic Actuators employ a novel mechanical design architecture which goes against the common machine design principal of "stiffer is better." A compliant element is placed between the gear train and driven load to intentionally reduce the stiffness of the actuator. A position sensor measures the deflection, and the force output is accurately calculated using Hooke"s Law (F=Kx). A control loop then servos the actuator to the desired output force. The resulting actuator has inherent shock tolerance, high force fidelity and extremely low impedance. These characteristics are desirable in many applications including legged robots, exoskeletons for human performance amplification, robotic arms, haptic interfaces, and adaptive suspensions. We describe several variations of Series Elastic Actuators that have been developed using both electric and hydraulic components.

  4. Ubx Regulates Differential Enlargement and Diversification of Insect Hind Legs

    PubMed Central

    Mahfooz, Najmus; Turchyn, Nataliya; Mihajlovic, Michelle; Hrycaj, Steven; Popadić, Aleksandar

    2007-01-01

    Differential enlargement of hind (T3) legs represents one of the hallmarks of insect evolution. However, the actual mechanism(s) responsible are yet to be determined. To address this issue, we have now studied the molecular basis of T3 leg enlargement in Oncopeltus fasciatus (milkweed bug) and Acheta domesticus (house cricket). In Oncopeltus, the T3 tibia displays a moderate increase in size, whereas in Acheta, the T3 femur, tibia, and tarsus are all greatly enlarged. Here, we show that the hox gene Ultrabithorax (Ubx) is expressed in the enlarged segments of hind legs. Furthermore, we demonstrate that depletion of Ubx during embryogenesis has a primary effect in T3 legs and causes shortening of leg segments that are enlarged in a wild type. This result shows that Ubx is regulating the differential growth and enlargement of T3 legs in both Oncopeltus and Acheta. The emerging view suggests that Ubx was co-opted for a novel role in regulating leg growth and that the transcriptional modification of its expression may be a universal mechanism for the evolutionary diversification of insect hind legs. PMID:17848997

  5. Ontogenetic shifts in functional morphology of dragonfly legs (Odonata: Anisoptera).

    PubMed

    Leipelt, Klaus Guido; Suhling, Frank; Gorb, Stanislav N

    2010-12-01

    Anisopteran leg functions change dramatically from the final larval stadium to the adult. Larvae use legs mainly for locomotion, walking, climbing, clinging, or burrowing. Adults use them for foraging and grasping mates, for perching, clinging to the vegetation, and for repelling rivals. In order to estimate the ontogenetic shift in the leg construction from the larva to the adult, this study quantitatively compared lengths of fore, mid, and hind legs and the relationships between three leg segments, femur, tibia, and tarsus, in larval and adult Anisoptera of the families Gomphidae, Aeshnidae, Cordulegastridae, Corduliidae, and Libellulidae, represented by two species each. We found that leg segment length ratio as well as ontogenetic shift in length ratios was different between families, but rather similar within the families. While little ontogenetic shift occurred in Aeshnidae, there were some modifications in Corduliidae and Libellulidae. The severest shift occurred in Gomphidae and Cordulegastridae, both having burrowing larvae. These two families form a cluster, which is in contrast to their taxonomic relationship within the Anisoptera. Cluster analysis implies that the function of larval legs is primarily responsible for grouping, whereas adult behavior or the taxonomic relationships do not explain the grouping. This result supports the previous hypothesis about the convergent functional shift of leg characters in the dragonfly ontogenesis.

  6. X-Ray Exam: Lower Leg (Tibia and Fibula)

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Lower Leg (Tibia and Fibula) KidsHealth > For Parents > X-Ray Exam: Lower Leg (Tibia and Fibula) A A ... Radiografía: tibia y peroné What It Is An X-ray of the tibia and fibula is a safe ...

  7. X-Ray Exam: Lower Leg (Tibia and Fibula)

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old X-Ray Exam: Lower Leg (Tibia and Fibula) KidsHealth > For Parents > X-Ray Exam: Lower Leg (Tibia and Fibula) Print A ... Radiografía: tibia y peroné What It Is An X-ray of the tibia and fibula is a safe ...

  8. ODYSSEUS autonomous walking robot: The leg/arm design

    NASA Technical Reports Server (NTRS)

    Bourbakis, N. G.; Maas, M.; Tascillo, A.; Vandewinckel, C.

    1994-01-01

    ODYSSEUS is an autonomous walking robot, which makes use of three wheels and three legs for its movement in the free navigation space. More specifically, it makes use of its autonomous wheels to move around in an environment where the surface is smooth and not uneven. However, in the case that there are small height obstacles, stairs, or small height unevenness in the navigation environment, the robot makes use of both wheels and legs to travel efficiently. In this paper we present the detailed hardware design and the simulated behavior of the extended leg/arm part of the robot, since it plays a very significant role in the robot actions (movements, selection of objects, etc.). In particular, the leg/arm consists of three major parts: The first part is a pipe attached to the robot base with a flexible 3-D joint. This pipe has a rotated bar as an extended part, which terminates in a 3-D flexible joint. The second part of the leg/arm is also a pipe similar to the first. The extended bar of the second part ends at a 2-D joint. The last part of the leg/arm is a clip-hand. It is used for selecting several small weight and size objects, and when it is in a 'closed' mode, it is used as a supporting part of the robot leg. The entire leg/arm part is controlled and synchronized by a microcontroller (68CH11) attached to the robot base.

  9. Running on uneven ground: leg adjustments to altered ground level.

    PubMed

    Müller, Roy; Blickhan, Reinhard

    2010-08-01

    In locomotion, humans have to deal with changes in ground level like pavement or stairs. When they encounter uneven ground with changes in terrain height, they reduce their angle of attack and leg stiffness on a step. This strategy was found for the single step upward movement. However, are these adjustments the result of a general strategy? In our study we focused on leg adjustments while running up and down, implying permanent adaptation to a new track level. To investigate this, we measured ten healthy participants as they ran along a runway with 10 cm increased and 10 cm lowered steps. We found that ground reaction force, leg length, leg stiffness, and angle of attack were adjusted to the direction of the vertical disturbance (up or down) but also to its length. When running upwards, leg stiffness decreased by about 20.4% on the single step and by about 9.3% on the permanently elevated track step. In addition to that - when running downwards - leg stiffness decreased in preparation for the downward step by about 18.8%. We also observed that the angle of attack diminished on elevated contact from 61 degrees to 59 degrees, and increased on lowered contact from 61 degrees to 65 degrees. The adjustment of leg stiffness seemed to be actively achieved, whereas the angle of attack appeared to be passively adjusted, consistent with a running model that includes leg retraction in late swing phase.

  10. Treatment of sickle cell leg ulcers with pentoxifylline.

    PubMed

    Frost, M L; Treadwell, P

    1990-06-01

    A 58-year-old black man with leg ulcers of 43 years duration responded to pentoxifylline 400 mg tid in 8 months. The ability of pentoxifylline to increase erythrocyte flexibility and decrease blood viscosity was the basis for our use of this agent. Oral pentoxifylline may be a useful adjunct in healing sickle cell leg ulcers and preventing their recurrence.

  11. Auger tension leg platform cathodic protection system

    SciTech Connect

    Goolsby, A.D.; Smith, J.D.

    1995-11-01

    In 1986, Shell began investigating corrosion control systems for a generic 3,000 ft. water depth Tension Leg Platform (TLP) type structure to be located in the north-central Gulf of Mexico. In 1987, the 2,850 ft. deep Garden Banks block 426 ``Auger`` location was chosen for the first TLP, and the detailed design process began in earnest. During late 1993 and early 1994, the Auger hull was mated with the other components at its permanent site, and first oil and gas production began April 15, 1994. This paper describes the corrosion control design for the exterior submerged and buried steel surfaces of the 2,850 ft. (869 m) water depth Auger Tension Leg Platform structure. Each major type of component (hull, subsea marine wellhead/guidebase, tendon foundation template, tendon, and production riser) has its own combination of coating system and cathodic protection system designed for a thirty five year lifetime. Cathodic protection (CP) is achieved using a variety of sacrificial anode alloys and geometries (e.g. bracelet, flush-mount, and standoff anodes). Anode and cathode CP design parameters for each component depend upon water depth, and were developed using field test data, laboratory studies, field measurements on existing structures, and available literature information. CP design was performed using design spreadsheets constructed for each component, which optimized anode geometries. Extensive quality assurance efforts were part of the anode procurement process, to ensure performance for the intended life of the corrosion-control systems. Results of early in-service CP surveys of the tendons and guidebases are presented, showing the successful achievement of cathodic protection against seawater corrosion. Corrosion control of one additional system, the eight point lateral mooring system, is not addressed here.

  12. EMGs Analysis of Lumbar, Pelvic and Leg Muscles in Leg Length Discrepancy Adolescents

    NASA Astrophysics Data System (ADS)

    Sotelo-Barroso, Fernando; Márquez-Gamiño, Sergio; Caudillo-Cisneros, Cipriana

    2004-09-01

    To evaluate differences in surface electromyography (EMGs) activity of lumbar, pelvic and leg muscles in adolescents with and without LLD. EMGs activity records were taken during rest and maximal isometric voluntary contractions (MIVC). Peak to peak amplitude (PPA), mean rectified voltage (MRV) and root mean square (RMS), were analyzed. Statistical differences between short and large sides of LLD adolescents, were found (p<0.05). Higher values occurred in shorter limb muscles. No significative differences were found between left and right legs of the control subjects. When EMGs values were compared between short and large sides of LLD subjects with ipsilateral sides of controls, selective, statistically different EMGs values were exhibited. It is suggested that adaptative behavior to secondary biomechanical and/or neural changes occurred, even when none clinical symptoms were reported. The observations were remarked by the absence of EMGs differences between right and left sides of control subjects.

  13. Device for absorbing horizontally directed impacts on the support legs of an artificial island during lowering and lifting of the legs respectively

    SciTech Connect

    Boon, B.

    1984-06-26

    Device for absorbing horizontally directed impact loads on the supporting legs of an artificial island comprising a pontoon and legs that are movable in the vertical direction and can be locked when the legs are lowered or lifted respectively further comprising energy absorbing and/or transfering means (2) extending downwardly from the lower part (1) of each of the legs.

  14. A survey of bio-inspired compliant legged robot designs.

    PubMed

    Zhou, Xiaodong; Bi, Shusheng

    2012-12-01

    The roles of biological springs in vertebrate animals and their implementations in compliant legged robots offer significant advantages over the rigid legged ones in certain types of scenarios. A large number of robotics institutes have been attempting to work in conjunction with biologists and incorporated these principles into the design of biologically inspired robots. The motivation of this review is to investigate the most published compliant legged robots and categorize them according to the types of compliant elements adopted in their mechanical structures. Based on the typical robots investigated, the trade-off between each category is summarized. In addition, the most significant performances of these robots are compared quantitatively, and multiple available solutions for the future compliant legged robot design are suggested. Finally, the design challenges for compliant legged robots are analysed. This review will provide useful guidance for robotic designers in creating new designs by inheriting the virtues of those successful robots according to the specific tasks.

  15. Simultaneous velocity and temperature measurements in turbulent flows using laser-cantilver anemometry and a thermocouple sensor

    NASA Astrophysics Data System (ADS)

    Hölling, Michael; Heidemann, Florian; Beenhakker, Marino; Barth, Stephan; Kittel, Achim; Peinke, Joachim

    2006-11-01

    We present a setup that combines our newly developed laser-cantilever anemometer (LCA) and temperature sensor. These sensors allow for high temporal and spatial resolution measurements. The LCA measures flow velocity by optically detecting the deflection of a tiny cantilever. A coaxial thermocouple of gold and platinum with a diameter of around 1 micrometer gives information about the temperature. The goal of the work is to measure fluid temperature and velocity in 'one spacial point' by positioning the sensor tips as close to one another as possible. Due to the different measurement principles of both sensors we do not expect any significant interference. In the analysis we focus on correlations between temperature fluctuations and velocity fluctuations, which is of current interest in local isotropic turbulence research.

  16. Recovery and radiation corrections and time constants of several sizes of shielded and unshielded thermocouple probes for measuring gas temperature

    NASA Technical Reports Server (NTRS)

    Glawe, G. E.; Holanda, R.; Krause, L. N.

    1978-01-01

    Performance characteristics were experimentally determined for several sizes of a shielded and unshielded thermocouple probe design. The probes are of swaged construction and were made of type K wire with a stainless steel sheath and shield and MgO insulation. The wire sizes ranged from 0.03- to 1.02-mm diameter for the unshielded design and from 0.16- to 0.81-mm diameter for the shielded design. The probes were tested through a Mach number range of 0.2 to 0.9, through a temperature range of room ambient to 1420 K, and through a total-pressure range of 0.03 to 0.2.2 MPa (0.3 to 22 atm). Tables and graphs are presented to aid in selecting a particular type and size. Recovery corrections, radiation corrections, and time constants were determined.

  17. Safe and consistent method of spot-welding platinum thermocouple wires and foils for high temperature measurements

    NASA Astrophysics Data System (ADS)

    Orr, G.; Roth, M.

    2012-08-01

    A low-voltage (mV) electronically triggered spot welding system for fabricating fine thermocouples and thin sheets used in high-temperature characterization of materials' properties is suggested. The system is based on the capacitance discharge method with a timed trigger for obtaining reliable and consistent welds. In contrast to existing techniques based on employing high voltage DC supplies for charging the capacitor or supplies with positive and negative rails, this method uses a simple, standard dual power supply available at most of the physical laboratories or can be acquired at a low cost. In addition, an efficient and simple method of fabricating non-sticking electrodes that do not contaminate the weld area is suggested and implemented.

  18. High-temperature thermocouple and heat flux gauge using a unique thin film-hardware hot junction

    NASA Technical Reports Server (NTRS)

    Liebert, C. H.; Holanda, R.; Hippensteele, S. A.; Andracchio, C. A.

    1985-01-01

    A special thin film-hardware material thermocouple (TC) and heat flux gauge concept for a reasonably high temperature and high flux flat plate heat transfer experiment was fabricated and tested to gauge temperatures of 911 K. This concept was developed for minimal disturbance of boundary layer temperature and flow over the plates and minimal disturbance of heat flux through the plates. Comparison of special heat flux gauge Stanton number output at steady-state conditions with benchmark literature data was good and agreement was within a calculated uncertainty of the measurement system. Also, good agreement of special TC and standard TC outputs was obtained and the results are encouraging. Oxidation of thin film thermoelements was a primary failure mode after about 5 of operation.

  19. Detection of Periodic Leg Movements by Machine Learning Methods Using Polysomnographic Parameters Other Than Leg Electromyography

    PubMed Central

    Umut, İlhan; Çentik, Güven

    2016-01-01

    The number of channels used for polysomnographic recording frequently causes difficulties for patients because of the many cables connected. Also, it increases the risk of having troubles during recording process and increases the storage volume. In this study, it is intended to detect periodic leg movement (PLM) in sleep with the use of the channels except leg electromyography (EMG) by analysing polysomnography (PSG) data with digital signal processing (DSP) and machine learning methods. PSG records of 153 patients of different ages and genders with PLM disorder diagnosis were examined retrospectively. A novel software was developed for the analysis of PSG records. The software utilizes the machine learning algorithms, statistical methods, and DSP methods. In order to classify PLM, popular machine learning methods (multilayer perceptron, K-nearest neighbour, and random forests) and logistic regression were used. Comparison of classified results showed that while K-nearest neighbour classification algorithm had higher average classification rate (91.87%) and lower average classification error value (RMSE = 0.2850), multilayer perceptron algorithm had the lowest average classification rate (83.29%) and the highest average classification error value (RMSE = 0.3705). Results showed that PLM can be classified with high accuracy (91.87%) without leg EMG record being present. PMID:27213008

  20. Cold fiber solid-phase microextraction device based on thermoelectric cooling of metal fiber.

    PubMed

    Haddadi, Shokouh Hosseinzadeh; Pawliszyn, Janusz

    2009-04-03

    A new cold fiber solid-phase microextraction device was designed and constructed based on thermoelectric cooling. A three-stage thermoelectric cooler (TEC) was used for cooling a copper rod coated with a poly(dimethylsiloxane) (PDMS) hollow fiber, which served as the solid-phase microextraction (SPME) fiber. The copper rod was mounted on a commercial SPME plunger and exposed to the cold surface of the TEC, which was enclosed in a small aluminum box. A heat sink and a fan were used to dissipate the generated heat at the hot side of the TEC. By applying an appropriate dc voltage to the TEC, the upper part of the copper rod, which was in contact to the cold side of the TEC, was cooled and the hollow fiber reached a lower temperature through heat transfer. A thermocouple was embedded in the cold side of the TEC for indirect measurement of the fiber temperature. The device was applied in quantitative analysis of off-flavors in a rice sample. Hexanal, nonanal, and undecanal were chosen as three off-flavors in rice. They were identified according to their retention times and analyzed by GC-flame ionization detection instrument. Headspace extraction conditions (i.e., temperature and time) were optimized. Standard addition calibration graphs were obtained at the optimized conditions and the concentrations of the three analytes were calculated. The concentration of hexanal was also measured using a conventional solvent extraction method (697+/-143ng/g) which was comparable to that obtained from the cold fiber SPME method (644+/-8). Moreover, the cold fiber SPME resulted in better reproducibility and shorter analysis time. Cold fiber SPME with TEC device can also be used as a portable device for field sampling.

  1. Protection against high intravascular pressure in giraffe legs.

    PubMed

    Petersen, Karin K; Hørlyck, Arne; Ostergaard, Kristine H; Andresen, Joergen; Broegger, Torbjoern; Skovgaard, Nini; Telinius, Niklas; Laher, Ismael; Bertelsen, Mads F; Grøndahl, Carsten; Smerup, Morten; Secher, Niels H; Brøndum, Emil; Hasenkam, John M; Wang, Tobias; Baandrup, Ulrik; Aalkjaer, Christian

    2013-11-01

    The high blood pressure in giraffe leg arteries renders giraffes vulnerable to edema. We investigated in 11 giraffes whether large and small arteries in the legs and the tight fascia protect leg capillaries. Ultrasound imaging of foreleg arteries in anesthetized giraffes and ex vivo examination revealed abrupt thickening of the arterial wall and a reduction of its internal diameter just below the elbow. At and distal to this narrowing, the artery constricted spontaneously and in response to norepinephrine and intravascular pressure recordings revealed a dynamic, viscous pressure drop along the artery. Histology of the isolated median artery confirmed dense sympathetic innervation at the narrowing. Structure and contractility of small arteries from muscular beds in the leg and neck were compared. The arteries from the legs demonstrated an increased media thickness-to-lumen diameter ratio, increased media volume, and increased numbers of smooth muscle cells per segment length and furthermore, they contracted more strongly than arteries from the neck (500 ± 49 vs. 318 ± 43 mmHg; n = 6 legs and neck, respectively). Finally, the transient increase in interstitial fluid pressure following injection of saline was 5.5 ± 1.7 times larger (n = 8) in the leg than in the neck. We conclude that 1) tissue compliance in the legs is low; 2) large arteries of the legs function as resistance arteries; and 3) structural adaptation of small muscle arteries allows them to develop an extraordinary tension. All three findings can contribute to protection of the capillaries in giraffe legs from a high arterial pressure.

  2. 78 FR 68909 - Agency Information Collection (Knee and Lower Leg Conditions Disability Benefits Questionnaire...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-15

    ... AFFAIRS Agency Information Collection (Knee and Lower Leg Conditions Disability Benefits Questionnaire... Leg Conditions Disability Benefits Questionnaire)'' in any correspondence. FOR FURTHER INFORMATION... Control No. 2900-NEW (Knee and Lower Leg Conditions Disability Benefits Questionnaire)''....

  3. Single-leg squats can predict leg alignment in dancers performing ballet movements in “turnout”

    PubMed Central

    Hopper, Luke S; Sato, Nahoko; Weidemann, Andries L

    2016-01-01

    The physical assessments used in dance injury surveillance programs are often adapted from the sports and exercise domain. Bespoke physical assessments may be required for dance, particularly when ballet movements involve “turning out” or external rotation of the legs beyond that typically used in sports. This study evaluated the ability of the traditional single-leg squat to predict the leg alignment of dancers performing ballet movements with turnout. Three-dimensional kinematic data of dancers performing the single-leg squat and five ballet movements were recorded and analyzed. Reduction of the three-dimensional data into a one-dimensional variable incorporating the ankle, knee, and hip joint center positions provided the strongest predictive model between the single-leg squat and the ballet movements. The single-leg squat can predict leg alignment in dancers performing ballet movements, even in “turned out” postures. Clinicians should pay careful attention to observational positioning and rating criteria when assessing dancers performing the single-leg squat. PMID:27895518

  4. COLD VRS HEAT AFTER EXERCISE- IS THERE A CLEAR WINNER FOR MUSCLE SORENESS.

    PubMed

    Petrofsky, Jerrold; Khowailed, Iman Akef; Lee, Haneul; Berk, Lee; Bains, Gurinder; Akerkar, Siddhesh; Shah, Jinal; Al-Dabbak, Fuad; Laymon, Mike

    2015-08-14

    Due to the differences in the exercise type, temperature and timing of the use of cold and heat after exercise in different studies, there is no clear conclusion as to the efficacy of either modality on reducing delayed onset muscle soreness. One hundred subjects at similar fitness levels were examined. They accomplished leg squats for 15 minutes and heat and cold were applied after or 24 hours after exercise using ThermaCare heat or cold wraps. Measurements obtained were strength, the force to passively move the knee, analog visual pain scales, and blood myoglobin. Control subjects lost 24% strength after exercise. Subjects with heat or cold just after exercise only lost 4% strength (p<0.01). Cold applied after 24 hours was better than heat at 24 for strength recovery. Heat or cold applied after exercise was significantly better to prevent elastic tissue damage (p<0.01) while heat and cold immediate after exercise caused no loss in muscle myoglobin whereas heat or cold after 24 hours showed no less muscle damage from myoglobin than control subjects. Myoglobin in the control and heat and cold 24 groups averaged 135.1% of the baseline data but averaged 106.1% of baseline in the heat and cold immediate groups. For reducing pain, control subjects showed a significant amount of pain the days after exercise. But cold immediately after exercise or 24 hours later was superior to heat in reducing pain. In conclusion, both cold and heat appear to be efficacious in reducing muscle damage after exercise.

  5. Cold Vs. Heat After Exercise-Is There a Clear Winner for Muscle Soreness.

    PubMed

    Petrofsky, Jerrold S; Khowailed, Iman Akef; Lee, Haneul; Berk, Lee; Bains, Gurinder S; Akerkar, Siddhesh; Shah, Jinal; Al-Dabbak, Fuad; Laymon, Mike S

    2015-11-01

    Because of the differences in the exercise type, temperature, and timing of the use of cold and heat after exercise in different studies, there is no clear conclusion as to the efficacy of either modality on reducing delayed onset muscle soreness. One hundred subjects at similar fitness levels were examined. They accomplished leg squats for 15 minutes and heat and cold were applied after or 24 hours after exercise using ThermaCare heat or cold wraps. Measurements obtained were strength, the force to passively move the knee, analog visual pain scales, and blood myoglobin. Control subjects lost 24% strength after exercise. Subjects with heat or cold just after exercise only lost 4% strength (p < 0.01). For strength recovery, cold applied after 24 hours was better than heat at 24 hours. Heat or cold applied after exercise was significantly better to prevent elastic tissue damage (p < 0.01), whereas heat and cold immediately after exercise caused no loss in muscle myoglobin and heat or cold after 24 hours showed no less muscle damage from myoglobin than in control subjects. Myoglobin in the control and heat and cold 24-hour groups averaged 135.1% of the baseline data but averaged 106.1% of baseline in the immediate heat and cold groups. For reducing pain, control subjects showed a significant amount of pain the days after exercise. But cold immediately after exercise or 24 hours later was superior to heat in reducing pain. In conclusion, both cold and heat appear to be efficacious in reducing muscle damage after exercise.

  6. Bosons with long-range interactions on two-leg ladders in artificial magnetic fields

    NASA Astrophysics Data System (ADS)

    Natu, Stefan S.

    2015-11-01

    Motivated by experiments exploring the physics of neutral atoms in artificial magnetic fields, we study the ground state of bosons interacting with long-range dipolar interactions on a two-leg ladder. We focus on the limit where the number of particles per site is large and the interactions are weak. Using two complementary variational approaches, we find rich physics driven by the long-range forces. Generically, long-range interactions tend to destroy the Meissner phase in favor of modulated density wave phases. For example, nearest-neighbor interactions produce an interleg charge density wave phase, where the total density remains uniform but the density on each leg of the ladder is modulating in space, out of phase with one another. Next-nearest-neighbor interactions lead to a fully modulated biased ladder phase, where all of the particles are on one leg of the ladder. This state simultaneously breaks Z2 reflection symmetry and U (1 ) translation symmetry. For values of the flux near ϕ =π , we find a switching effect for arbitrarily weak interactions, where the density is modulated but the chiral current changes sign on every plaquette. Arbitrarily weak attractive interactions along the rungs destroy the Meissner phase completely, in favor of a modulated density wave phase. Remarkably, varying the rung to ladder hopping produces a cascade of first-order transitions between modulated density wave states with different wave vectors, which manifests itself as discrete jumps in the chiral current. Polarizing the dipoles along the ladder direction yields a region of phase space where a stable biased ladder phase occurs even at arbitrarily weak rung hopping. We discuss the experimental consequences of our work and draw connections between our work and recent experiments on cold atoms in synthetic dimensions.

  7. Don't break a leg: running birds from quail to ostrich prioritise leg safety and economy on uneven terrain

    PubMed Central

    Birn-Jeffery, Aleksandra V.; Hubicki, Christian M.; Blum, Yvonne; Renjewski, Daniel; Hurst, Jonathan W.; Daley, Monica A.

    2014-01-01

    Cursorial ground birds are paragons of bipedal running that span a 500-fold mass range from quail to ostrich. Here we investigate the task-level control priorities of cursorial birds by analysing how they negotiate single-step obstacles that create a conflict between body stability (attenuating deviations in body motion) and consistent leg force–length dynamics (for economy and leg safety). We also test the hypothesis that control priorities shift between body stability and leg safety with increasing body size, reflecting use of active control to overcome size-related challenges. Weight-support demands lead to a shift towards straighter legs and stiffer steady gait with increasing body size, but it remains unknown whether non-steady locomotor priorities diverge with size. We found that all measured species used a consistent obstacle negotiation strategy, involving unsteady body dynamics to minimise fluctuations in leg posture and loading across multiple steps, not directly prioritising body stability. Peak leg forces remained remarkably consistent across obstacle terrain, within 0.35 body weights of level running for obstacle heights from 0.1 to 0.5 times leg length. All species used similar stance leg actuation patterns, involving asymmetric force–length trajectories and posture-dependent actuation to add or remove energy depending on landing conditions. We present a simple stance leg model that explains key features of avian bipedal locomotion, and suggests economy as a key priority on both level and uneven terrain. We suggest that running ground birds target the closely coupled priorities of economy and leg safety as the direct imperatives of control, with adequate stability achieved through appropriately tuned intrinsic dynamics. PMID:25355848

  8. Out in the cold.

    PubMed

    Bates, Jane

    2016-05-04

    Every now and then, you say something to a patient and wonder whether you should have kept quiet. On this occasion, a female patient and I were indulging in a moment of shared empathy over an annoying symptom we both experience - permanently cold feet.

  9. Teaching "In Cold Blood."

    ERIC Educational Resources Information Center

    Berbrich, Joan D.

    1967-01-01

    The Truman Capote nonfiction novel, "In Cold Blood," which reflects for adolescents the immediacy of the real world, illuminates (1) social issues--capital punishment, environmental influence, and the gap between the "haves" and "have-nots," (2) moral issues--the complexity of man's nature, the responsibility of one…

  10. Cold Facts about Viruses.

    ERIC Educational Resources Information Center

    Pea, Celeste; Sterling, Donna R.

    2002-01-01

    Provides ways for students to demonstrate their understanding of scientific concepts and skills. Describes a mini-unit around the cold in which students can relate humans to viruses. Includes activities and a modified simulation that provides questions to guide students. Discusses ways that allows students to apply prior knowledge, take ownership…

  11. Recent Cold War Studies

    ERIC Educational Resources Information Center

    Pineo, Ronn

    2003-01-01

    Cold War historiography has undergone major changes since the 1991 collapse of the Soviet Union. For two years (1992-1993) the principal Soviet archives fell open to scholars, and although some of the richest holdings are now once again closed, new information continues to find its way out. Moreover, critical documentary information has become…

  12. Cold spray nozzle design

    DOEpatents

    Haynes, Jeffrey D.; Sanders, Stuart A.

    2009-06-09

    A nozzle for use in a cold spray technique is described. The nozzle has a passageway for spraying a powder material, the passageway having a converging section and a diverging section, and at least the diverging section being formed from polybenzimidazole. In one embodiment of the nozzle, the converging section is also formed from polybenzimidazole.

  13. Expert Cold Structure Development

    NASA Astrophysics Data System (ADS)

    Atkins, T.; Demuysere, P.

    2011-05-01

    The EXPERT Program is funded by ESA. The objective of the EXPERT mission is to perform a sub-orbital flight during which measurements of critical aero- thermodynamic phenomena will be obtained by using state-of-the-art instrumentation. As part of the EXPERT Flight Segment, the responsibility of the Cold Structure Development Design, Manufacturing and Validation was committed to the Belgian industrial team SONACA/SABCA. The EXPERT Cold Structure includes the Launcher Adapter, the Bottom Panel, the Upper Panel, two Cross Panels and the Parachute Bay. An additional Launcher Adapter was manufactured for the separation tests. The selected assembly definition and manufacturing technologies ( machined parts and sandwich panels) were dictated classically by the mass and stiffness, but also by the CoG location and the sensitive separation interface. Used as support for the various on-board equipment, the Cold Structure is fixed to but thermally uncoupled from the PM 1000 thermal shield. It is protect on its bottom panel by a thermal blanket. As it is a protoflight, analysis was the main tool for the verification. Low level stiffness and modal analysis tests have also been performed on the Cold Structure equipped with its ballast. It allowed to complete its qualification and to prepare SONACA/SABCA support for the system dynamic tests foreseen in 2011. The structure was finally coated with a thermal control black painting and delivered on time to Thales Alenia Space-Italy end of March 201.

  14. Evaluation of Thermoelectric Performance and Durability of Functionalized Skutterudite Legs

    NASA Astrophysics Data System (ADS)

    Skomedal, Gunstein; Kristiansen, Nils R.; Sottong, Reinhard; Middleton, Hugh

    2017-04-01

    Thermoelectric generators are a promising technology for waste heat recovery. As new materials and devices enter a market penetration stage, it is of interest to employ fast and efficient measurement methods to evaluate the long-term stability of thermoelectric materials in combination with metallization and coating (functionalized thermoelectric legs). We have investigated a method for measuring several thermoelectric legs simultaneously. The legs are put under a common temperature gradient, and the electrical characteristics of each leg are measured individually during thermal cycling. Using this method, one can test different types of metallization and coating applied to skutterudite thermoelectric legs and look at the relative changes over time. Postcharacterization of these initial tests with skutterudite legs using a potential Seebeck microprobe and an electron microscope showed that oxidation and interlayer diffusion are the main reasons for the gradual increase in internal resistance and the decrease in open-circuit voltage. Although we only tested skutterudite material in this work, the method is fully capable of testing all kinds of material, metallization, and coating. It is thus a promising method for studying the relationship between failure modes and mechanisms of functionalized thermoelectric legs.

  15. Respiratory and leg muscles perceived exertion during exercise at altitude.

    PubMed

    Aliverti, A; Kayser, B; Lo Mauro, A; Quaranta, M; Pompilio, P; Dellacà, R L; Ora, J; Biasco, L; Cavalleri, L; Pomidori, L; Cogo, A; Pellegrino, R; Miserocchi, G

    2011-07-31

    We compared the rate of perceived exertion for respiratory (RPE,resp) and leg (RPE,legs) muscles, using a 10-point Borg scale, to their specific power outputs in 10 healthy male subjects during incremental cycle exercise at sea level (SL) and high altitude (HA, 4559 m). Respiratory power output was calculated from breath-by-breath esophageal pressure and chest wall volume changes. At HA ventilation was increased at any leg power output by ∼ 54%. However, for any given ventilation, breathing pattern was unchanged in terms of tidal volume, respiratory rate and operational volumes of the different chest wall compartments. RPE,resp scaled uniquely with total respiratory power output, irrespectively of SL or HA, while RPE,legs for any leg power output was exacerbated at HA. With increasing respective power outputs, the rate of change of RPE,resp exponentially decreased, while that of RPE,legs increased. We conclude that RPE,resp uniquely relates to respiratory power output, while RPE,legs varies depending on muscle metabolic conditions.

  16. The need for a National Service Framework for leg ulcers.

    PubMed

    Bulbulia, R A; Poskitt, K R

    2010-10-01

    Leg ulcers are common and costly to treat, and the quality of care provided to patients with this condition varies widely across the UK. The introduction of specialized community-based leg ulcer clinics in Gloucestershire has been associated with increased ulcer healing rates and decreased rates of ulcer recurrence, but this model of care has not been widely replicated. One way of ending this 'postcode lottery' is to produce a National Service Framework for leg ulcers, with the aim of delivering high-quality evidence-based care via such clinics under the supervision of local consultant vascular surgeons. Existing National Service Frameworks cover a range of common conditions that are, like leg ulceration, associated with significant morbidity, disability and resource use. These documents aim to raise quality and decrease regional variations in health care across the National Health Service, and leg ulceration fulfils all the necessary criteria for inclusion in a National Service Framework. Centrally defined standards of care for patients with leg ulceration, and the reorganization and restructuring of local services to allow the accurate assessment and treatment of such patients are required. Without a National Service Framework to drive up the quality of care across the country, the treatment of patients with leg ulcers will remain suboptimal for the majority of those who suffer from this common and debilitating condition.

  17. Restless legs syndrome in patients on dialysis.

    PubMed

    Al-Jahdali, Hamdan H; Al-Qadhi, Waleed A; Khogeer, Haithm A; Al-Hejaili, Fayez F; Al-Ghamdi, Saeed M; Al Sayyari, Abdullah A

    2009-05-01

    Restless legs syndrome (RLS) is an extremely distressing problem experienced by patients on dialysis; the prevalence appears to be greater than in the general population, with a wide variation from 6.6% to 80%. The diagnosis of RLS is a clinical one, and its definition has been clarified and standardized by internationally recognized diagnostic criteria, published in 1995 by the International Restless Legs Syndrome Study Group (IRLSSG). This study was designed to find out the prevalence of RLS in Saudi patients with end-stage renal disease (ESRD) on maintenance dialysis. This is a cross sectional study carried out between May and Sept 2007 at two centers, King Abdulaziz Medical City-King Fahad National Guard Hospital (KAMC-KFNGH), Riyadh and King Faisal Specialist Hospital and Research Centre (KFHRC), Jeddah, Saudi Arabia. Data were gathered on 227 Saudi patients on chronic maintenance hemodialysis or chronic peritoneal dialysis. The prevalence of RLS was measured using IRLSSG's RLS Questionnaire (RLSQ). Potential risk factors for RLS including other sleep disorders, underlying cause of chronic renal failure, duration on dialysis, dialysis shift, biochemical tests and demographic data were also evaluated. The overall prevalence of RLS was 50.22% including 53.7% males and 46.3% females. Their mean age was 55.7 +/- 17.2 years and mean duration on dialysis 40.4 +/- 37.8 months. Significant predictors of RLS were history of diabetes mellitus (DM), coffee intake, afternoon dialysis, gender and type of dialysis (P= 0.03, 0.01, < 0.001, 0.05 and 0.009 respectively). Patients with RLS were found to be at increased risk of having insomnia and excessive daytime sleepiness (EDS) (P= < 0.001 and 0.001, respectively). Our study suggests that RLS is a very common problem in dialysis population and was significantly associated with other sleep disorders, particularly insomnia, and EDS. Optimal care of dialysis patient should include particular attention to the diagnosis and

  18. Interaction Between Leg Muscle Performance and Sprint Acceleration Kinematics

    PubMed Central

    Lockie, Robert G.; Jalilvand, Farzad; Callaghan, Samuel J.; Jeffriess, Matthew D.; Murphy, Aron J.

    2015-01-01

    This study investigated relationships between 10 m sprint acceleration, step kinematics (step length and frequency, contact and flight time), and leg muscle performance (power, stiffness, strength). Twenty-eight field sport athletes completed 10 m sprints that were timed and filmed. Velocity and step kinematics were measured for the 0–5, 5–10, and 0–10 m intervals to assess acceleration. Leg power was measured via countermovement jumps (CMJ), a five-bound test (5BT), and the reactive strength index (RSI) defined by 40 cm drop jumps. Leg stiffness was measured by bilateral and unilateral hopping. A three-repetition maximum squat determined strength. Pearson’s correlations and stepwise regression (p ≤ 0.05) determined velocity, step kinematics, and leg muscle performance relationships. CMJ height correlated with and predicted velocity in all intervals (r = 0.40–0.54). The 5BT (5–10 and 0–10 m intervals) and RSI (5–10 m interval) also related to velocity (r = 0.37–0.47). Leg stiffness did not correlate with acceleration kinematics. Greater leg strength related to and predicted lower 0–5 m flight times (r = −0.46 to −0.51), and a longer 0–10 m step length (r = 0.38). Although results supported research emphasizing the value of leg power and strength for acceleration, the correlations and predictive relationships (r2 = 0.14–0.29) tended to be low, which highlights the complex interaction between sprint technique and leg muscle performance. Nonetheless, given the established relationships between speed, leg power and strength, strength and conditioning coaches should ensure these qualities are expressed during acceleration in field sport athletes. PMID:26839607

  19. Impact of Restless Legs Syndrome on Cardiovascular Autonomic Control

    PubMed Central

    Bertisch, Suzanne M.; Muresan, Cristen; Schoerning, Laura; Winkelman, John W.; Taylor, J. Andrew

    2016-01-01

    Study Objectives: To examine whether patients with restless legs syndrome demonstrate specific alterations in cardiovascular autonomic control. Methods: Patients with moderate-severe restless legs syndrome (n = 20, 80% female) and controls (n = 20) matched for age, sex, body mass index, and free of hypertension and cardiovascular disease were enrolled. We assessed cardiovagal baroreflex gain via the modified Oxford technique, sympathetically mediated vascular responses to isometric exercise to fatigue, bradycardiac response to Valsalva maneuver, and respiratory sinus arrhythmia during paced breathing. Standard electrocardiography, beat-by-beat arterial pressure, respiration, and popliteal blood flow velocity were recorded continuously. Results: Resting blood pressure and heart rate were similar between groups. However, baroreflex gain averaged 14.3 ± 1.4 msec/mm Hg in restless legs syndrome and was lower than in controls (22.6 ± 3.5 msec/mm Hg, P = 0.04). Hemodynamic responses to isometric exercise were similar between groups, though participants with restless legs syndrome had lower leg blood flow (P < 0.001), with greater leg vascular resistance (P < 0.0001), before and during isometric exercise. Respiratory sinus arrhythmia and Valsalva ratios were similar between groups. Neither baroreflex gain nor vascular resistance was correlated with sleep duration, sleep quality, or symptom duration. Conclusion: Patients with restless legs syndrome demonstrate compromised cardiovagal control, specific to the arterial baroreflex, with greater peripheral vascular resistance, potentially due to heightened sympathetic outflow. These autonomic alterations may directly relate to the higher prevalence of cardiovascular disease in restless legs syndrome. Citation: Bertisch SM, Muresan C, Schoerning L, Winkelman JW, Taylor JA. Impact of restless legs syndrome on cardiovascular autonomic control. SLEEP 2016;39(3):565–571. PMID:26564128

  20. Thermoregulatory modeling for cold stress.

    PubMed

    Xu, Xiaojiang; Tikuisis, Peter

    2014-07-01

    Modeling for cold stress has generated a rich history of innovation, has exerted a catalytic influence on cold physiology research, and continues to impact human activity in cold environments. This overview begins with a brief summation of cold thermoregulatory model development followed by key principles that will continue to guide current and future model development. Different representations of the human body are discussed relative to the level of detail and prediction accuracy required. In addition to predictions of shivering and vasomotor responses to cold exposure, algorithms are presented for thermoregulatory mechanisms. Various avenues of heat exchange between the human body and a cold environment are reviewed. Applications of cold thermoregulatory modeling range from investigative interpretation of physiological observations to forecasting skin freezing times and hypothermia survival times. While these advances have been remarkable, the future of cold stress modeling is still faced with significant challenges that are summarized at the end of this overview.

  1. Punctuated Stratigraphic Appearance of Cold-Water Coral Reefs

    NASA Astrophysics Data System (ADS)

    Eberli, G. P.; Correa, T.; Massaferro, J. L.

    2008-05-01

    Existing and new data acquired with an AUV document a high abundance of cold-water coral mounds in the bottom of the Straits of Florida (SoF). These mounds display a large variability of shapes and heights. The abundance and variability encountered in these and modern cold-water coral mounds elsewhere is in stark contrast to lack of reported ancient cold-water coral reefs. Furthermore, the stratigraphic distribution suggests that cold-water corals punctuate the stratigraphic record with times of bloom and times of near complete absence. In the Florida Bahamas region, for example, the stratigraphic distribution is non-uniform. Preliminary age dating of the modern coral mounds produce ages of a few hundred to 1300 years for corals at the surface of the mounds. Sub-bottom profiles and seismic data across the investigated mound fields reveal that the "modern" mounds root in Pleistocene strata but are absent in the Pliocene strata below. Cores taken during ODP Legs 101 and 166 in the SoF confirm the punctuated appearance as deep-water coral rubble was penetrated only in the Pleistocene and in the upper Oligocene strata. The vast occurrence of Oligocene cold-water coral mounds is also visible on a 2-D seismic line in the northern SoF and on a 3-D seismic survey in the southwestern portion of the SoF. In this latter data set a mid-Miocene and the base of Tertiary seismic horizon also image mounded features. These spikes in reef development indicate that environmental conditions were only occasionally favorable for reef growth. The punctuated appearance is surprising as the core and seismic data document continuous current activity since the late Miocene in the SoF. We speculate that the "modern" bloom of cold-water coral reefs in the Pleistocene coincides with the onset of the large barrier reef systems in the Australia and Belize.

  2. Effects of ingestion of cold and hot water on the course of thermal changes in the stomach and intestine

    NASA Technical Reports Server (NTRS)

    Batinkov, Y. L.

    1979-01-01

    With the use of a thermocouple and mirror galvanometer, calibrated before the experiment and after each test, it was found that the normal temperature in the esophagus is 0.1-0.4 C higher than in the oral cavity, the temperature in the duodenum is somewhat less than in the stomach, but higher with cholecystitis, duodenitis or gastritis, the temperature in the normal stomach equals or is somewhat higher than in the esophagus, and that the temperature of distended stomachs frequently is lower than in the esophagus. It was found that hot water is retained in the stomach longer than cold water, and that both hot and cold water are allowed to pass into the duodenum when the water temperature becomes approximately equal to that of the surrounding organs.

  3. The cooling of printed circuit board mounted components using copper ladder heat conduction to a cold wall

    NASA Astrophysics Data System (ADS)

    Dale, I. C.

    1982-09-01

    A series of experimental tests, designed to investigate the cooling of printed circuit board (PCB) mounted dual-in-line (DIL) components within an avionic box using the copper ladder/cold wall technique is described. Areas of investigation include avionic box orientation, side wall conduction, top plate finning, mixed air-wash, avionic power reduction, cooling air temperature reduction, cooling air mass flow rate reduction, cold wall heat pick-up and avionic box insulation. Results were obtained from thermocouple temperature measurements. The use of an aluminum alloy interplate to cool two adjacent PCBs is discussed. Results in graphic form are included together with a list of conclusions on the effects of all the major parameters considered.

  4. Palaeontology: leg feathers in an Early Cretaceous bird.

    PubMed

    Zhang, Fucheng; Zhou, Zhonghe

    2004-10-21

    Here we describe a fossil of an enantiornithine bird from the Early Cretaceous period in China that has substantial plumage feathers attached to its upper leg (tibiotarsus). The discovery could be important in view of the relative length and aerodynamic features of these leg feathers compared with those of the small 'four-winged' gliding dinosaur Microraptor and of the earliest known bird, Archaeopteryx. They may be remnants of earlier long, aerodynamic leg feathers, in keeping with the hypothesis that birds went through a four-winged stage during the evolution of flight.

  5. Restless Leg Syndrome in Neurologic and Medical Disorders.

    PubMed

    Askenasy, Nadir; Askenasy, Jean-Jacques

    2015-09-01

    Adopting prior models of sleep-wake transitions, a flip-flop switch in synchronized neurotransmitter activity is proposed to underlie restless leg syndrome onset. In this model, leg quiescence homeostasis sustained through concerted activities of several neurotransmitters in basal ganglia is perturbed and produces striatal motor activity along sensory activity associated with thalamocortical circuits (conscious urge and discomfort). This model explains the association of restless leg syndrome with a wide variety of associated pathologies emphasizing that perturbed function and imbalance may occur under different steady states of neurotransmitter levels. Likewise, this concept links various central and peripheral etiologies and integrates the augmenting and transient effects of therapeutic neuromodulators.

  6. [Innovative therapy for leg ulcers: Electrostimulation].

    PubMed

    Maillard, H

    2015-01-01

    Chronic wounds can take a long time to heal despite appropriate therapy based upon aetiology and use of suitable dressings. The success of electrostimulation is based upon the existence within the skin of the endogenous currents involved in the wound healing process. Where skin continuity is broken by a wound, these electrical potentials are short-circuited, resulting in leakage of electrical current. Woundel(®) therapy is the only such treatment currently available in France and is based on the use of continuous pulsed current that generates an electrical field near the endogenous electrical fields. It utilises a console to deliver the electrical impulses, a dressing electrode and a dispersion electrode. The electrode dressing is left on the wound for 3 days, and venous compression bandaging may be applied to the leg, taking care to leave the connector free. Negative polarity stimulates migration of fibroblasts, resulting in elimination of fibrin. Positive polarity causes keratinocyte migration, which in turn leads to epidermisation. Electrostimulation is of recognised utility in the healing of chronic wounds: it has been assigned a high-level recommendation in the European and American guidelines for the treatment of venous ulcers and bedsores with proof level of A. Further, the analgesic effect of electrostimulation has been demonstrated in several studies. Electrostimulation is already well developed in France among wound specialists, but prospective studies are planned so that it may be used at patients' homes.

  7. A digital driven right leg circuit.

    PubMed

    Haberman, Marcelo; Spinelli, Enrique

    2010-01-01

    A novel scheme and a digital approach to the Driven Right Leg Circuit (DRL) are presented. It presents an ultra high common mode (CM) reduction of power line interference (higher than 80dB) without endangering stability. This improves by 40-50dB the CM reduction provided by a classical analog DRL, retaining the same stability criterion. The improvement comes from the inclusion of a high Q resonator in parallel with the common mode amplifier. It provides a large gain at power line frequency (50/60 Hz) whereas it does not significantly affect the open loop gain for high frequencies. The proposed scheme can be thought as an analog circuit, but the accuracy required, mainly in the resonator frequency response, leads to a digital implementation. In this way, component ageing and thermal fluctuation problems are avoided, as well as the need for manual adjusting. A prototype of the proposed DRL circuit was built and tested in laboratory conditions showing an open-loop gain of 74dB at 50Hz. It was also tested by acquiring real EEG signals.

  8. The thigh and leg of Homo naledi.

    PubMed

    Marchi, Damiano; Walker, Christopher S; Wei, Pianpian; Holliday, Trenton W; Churchill, Steven E; Berger, Lee R; DeSilva, Jeremy M

    2017-03-01

    This paper describes the 108 femoral, patellar, tibial, and fibular elements of a new species of Homo (Homo naledi) discovered in the Dinaledi chamber of the Rising Star cave system in South Africa. Homo naledi possesses a mosaic of primitive, derived, and unique traits functionally indicative of a bipedal hominin adapted for long distance walking and possibly running. Traits shared with australopiths include an anteroposteriorly compressed femoral neck, a mediolaterally compressed tibia, and a relatively circular fibular neck. Traits shared with Homo include a well-marked linea aspera, anteroposteriorly thick patellae, relatively long tibiae, and gracile fibulae with laterally oriented lateral malleoli. Unique features include the presence of two pillars on the superior aspect of the femoral neck and a tubercular distal insertion of the pes anserinus on the tibia. The mosaic morphology of the H. naledi thigh and leg appears most consistent with a species intermediate between Australopithecus spp. and Homo erectus and, accordingly, may offer insight into the nature of the earliest members of genus Homo. These fossils also expand the morphological diversity of the Homo lower limb, perhaps indicative of locomotor diversity in our genus.

  9. Restless legs syndrome and pregnancy: A review

    PubMed Central

    Srivanitchapoom, Prachaya; Pandey, Sanjay; Hallett, Mark

    2014-01-01

    Restless legs syndrome (RLS) is a common sensorimotor neurological disorder that is diagnosed according to the revised criteria of the International RLS Study Group (IRLSSG). The pathophysiology of RLS is still unknown and its prevalence is influenced by ethnicity, age, and gender. RLS is divided into two types by etiology: primary or idiopathic and secondary. Primary RLS is strongly influenced by a genetic component while secondary RLS is caused by other associated conditions such as end-stage renal disease or peripheral neuropathy. Another common condition associated with RLS is pregnancy. The prevalence of RLS during pregnancy is two to three times higher than in the normal population and is influenced by the trimester and the number of parity. The main mechanisms that may contribute to the pathophysiology of RLS during pregnancy are hormonal changes and iron and folate status. Standard medications for treating RLS during pregnancy are not established. Most medications have been used according to the evidence from non-pregnant patients. Therefore, consideration of the medical treatment for treating RLS during pregnancy should be balanced between the benefit of relieving the symptoms and maternal and fetal risk. In general, the prognosis of RLS during pregnancy is good and symptoms are usually relieved after delivery. PMID:24768121

  10. Why Do Alcoholic Beverages Have "Legs"?

    NASA Astrophysics Data System (ADS)

    Silverstein, Todd P.

    1998-06-01

    After a sip of wine, "legs" of liquid typically run up and down the inside of the glass for many minutes. This phenomenon stems from the dipole-dipole intermolecular forces that are so important in understanding the physical behavior of aqueous solutions. The combination of cohesive forces within the liquid and adhesive forces between the liquid and a solid surface can explain physical phenomena such as viscosity, surface tension, capillary action, and the shape of the meniscus. Aqueous ethanol solutions tend to have cohesive forces that are weaker than those of pure water, while their adhesive forces toward polar glass surfaces are roughly equivalent to those of water. Because adhesive forces are stronger than cohesive forces, wine may cling to the glass surface, hovering high above the remainder of the wine in the bottom of the glass. As ethanol evaporates, however, cohesive forces increase until the wine falls in a thin stream. Upon touching the surface of the wine in the bottom of the glass, ethanol concentration is restored, cohesive forces weaken, and the thin stream of wine rises back to the top of the glass.

  11. Restless legs syndrome and pregnancy: a review.

    PubMed

    Srivanitchapoom, Prachaya; Pandey, Sanjay; Hallett, Mark

    2014-07-01

    Restless legs syndrome (RLS) is a common sensorimotor neurological disorder that is diagnosed according to the revised criteria of the International RLS Study Group (IRLSSG). The pathophysiology of RLS is still unknown and its prevalence is influenced by ethnicity, age, and gender. RLS is divided into two types by etiology: primary or idiopathic and secondary. Primary RLS is strongly influenced by a genetic component while secondary RLS is caused by other associated conditions such as end-stage renal disease or peripheral neuropathy. Another common condition associated with RLS is pregnancy. The prevalence of RLS during pregnancy is two to three times higher than in the normal population and is influenced by the trimester and the number of parity. The main mechanisms that may contribute to the pathophysiology of RLS during pregnancy are hormonal changes and iron and folate status. Standard medications for treating RLS during pregnancy are not established. Most medications have been used according to the evidence from non-pregnant patients. Therefore, consideration of the medical treatment for treating RLS during pregnancy should be balanced between the benefit of relieving the symptoms and maternal and fetal risk. In general, the prognosis of RLS during pregnancy is good and symptoms are usually relieved after delivery.

  12. Athermal laser treatment of the diabetic leg

    NASA Astrophysics Data System (ADS)

    Ignat, P.; Suteanu, S.; Brojbeanu, Gabriela; Vasiliu, Virgil V.

    1995-03-01

    This work shows the result obtained in the medical clinic of the `Dr. I. Cantacuzino Hospital' on a lot of 43 diabetic patients using the `LASSIS' devices composed of a He-Ne laser and 4 semiconductor lasers. The 43 patients showed various clinic pictures of a diabetic leg (diabetic arteriopathy and neuropathy) 16 of the lot showed an arteriopathy with claudication and a decrease of pulses oscillometrically measurements, 15 had ulceration and a beginning of gangrene and the other 12 showed a plantary boring ill. There has been achieved an amelioration of the oscillometric index of the claudication while walking the amelioration of local circulation, together with the limitation of the necrosis. For the boring ill, there has been achieved the acceleration of the granulating and epithelization process avoiding surgeries, suppuration and cutaneous plasties. The response to the laser treatment was compared to the response to the classic treatment (vasodilatation surgery unstrapping, antibiotherapy) on a proving lot. We appreciated that the cicatrization and local vasodilatation with athermal laser treatment should be a hope for the treatment of patients suffering of diabetic arteriopathy and neuropathy.

  13. Remedies for Common Cold Symptoms

    PubMed Central

    Miller, Penny F.

    1991-01-01

    Individuals suffering from intolerable symptoms of the common cold can now be advised of safe and effective products for symptomatic relief. This article describes and discusses four categories of drugs used to treat the common cold. To simplify the product selection process for family physicians, suggestions are included for possible ingredients for treatments of specific cold symptoms. PMID:21234087

  14. Human whole body cold adaptation

    PubMed Central

    Daanen, Hein A.M.; Van Marken Lichtenbelt, Wouter D.

    2016-01-01

    ABSTRACT Reviews on whole body human cold adaptation generally do not distinguish between population studies and dedicated acclimation studies, leading to confusing results. Population studies show that indigenous black Africans have reduced shivering thermogenesis in the cold and poor cold induced vasodilation in fingers and toes compared to Caucasians and Inuit. About 40,000 y after humans left Africa, natives in cold terrestrial areas seems to have developed not only behavioral adaptations, but also physiological adaptations to cold. Dedicated studies show that repeated whole body exposure of individual volunteers, mainly Caucasians, to severe cold results in reduced cold sensation but no major physiological changes. Repeated cold water immersion seems to slightly reduce metabolic heat production, while repeated exposure to milder cold conditions shows some increase in metabolic heat production, in particular non-shivering thermogenesis. In conclusion, human cold adaptation in the form of increased metabolism and insulation seems to have occurred during recent evolution in populations, but cannot be developed during a lifetime in cold conditions as encountered in temperate and arctic regions. Therefore, we mainly depend on our behavioral skills to live in and survive the cold. PMID:27227100

  15. Clinical interventions for venous leg ulcers: Proposals to improve the quality of clinical leg ulcer research.

    PubMed

    Lazarus, Gerald S; Kirsner, Robert S; Zenilman, Jonathan; Valle, M Frances; Margolis, David J; Cullum, Nicky; Driver, Vickie R; Gould, Lisa; Lindsay, Ellie; Tunis, Sean; Marston, William; Bass, Eric; Ennis, William; Davidson, Jeffrey; Bowden, Jeremy

    2016-09-01

    The present status of clinical leg ulcer healing research was reviewed by 25 experts over 2 days on September 28 and 29, 2015. Multiple clinical effectiveness reviews were presented suggesting that published clinical wound healing research often does not meet present (2015) evidence based standards. Specific areas requiring remediation were highlighted and approaches to overcoming existing challenges were proposed. Participants using anonymous voting technology developed an action plan to resolve perceived deficiencies. Statements were accepted if 75% of participants agreed. Older patients with a high frequency of comorbid conditions posed particular difficulties in designing clinical research protocols and better diagnostic categorization is necessary A standardized model template for collecting information about diagnosis and evaluation of the effect of interventions on healing of all types of leg ulcers was considered a high priority. Such a model template could be modified depending on the specific etiology of the leg ulcers. Generally agreed on quantifiable standards to establish degree of morbidity was considered a high priority. There was universal agreement that sources of funding and conflicts of interest needed to be disclosed in presentations and all publications. All clinical research studies should be registered with appropriate authorities. There was substantial enthusiasm for a clinical research network with quality standards for membership and an advisory research core available to investigators. Such a network should be funded and actively managed to insure long-term viability. The governance of such an entity needs to be established by the wound care community. The present trend to integrate patients into the clinical research process was endorsed and there was enthusiasm to develop patient advocacy for wound healing research.

  16. [Influence of Achilles tendon vibration on the human vertical posture during standing with asymmetrical leg loading].

    PubMed

    Kazennikov, O V; Kireeva, T B; Shlykov, V Iu

    2014-01-01

    The shift of center of pressure (CP) of body and CP of each leg was studied during Achilles tendon vibration of one or both legs while subject was standing with symmetrical load on the legs or with the load transferred on one leg. The CP shift of standing subject during unilateral Achilles tendon vibration depended both on the side of the tendon vibration and on the leg load. When standing with a load transferred on one leg the shift of common CP was larger than when the vibration was applied to the loaded leg. The CP shift of one leg was greater if the vibration, and the load was applied to it. Vibration of unloaded leg caused a CP shift in the contralateral loaded leg. In this case, the vibration of left unloaded leg caused no noticeable CP shift of left leg, while the vibration of the unloaded right leg caused CP shift of right foot. In the same conditions of load and vibration the CP displacement of right leg was larger than the CP shift of left foot. It can be assumed that the change in the load on the leg and unilateral vibration of leg muscles change of the internal representation of the vertical body axis, which affects the CP position of one leg during the muscles vibration.

  17. Measurement of L-(1-/sup 14/C)leucine kinetics in splanchnic and leg tissues in humans. Effect of amino acid infusion

    SciTech Connect

    Gelfand, R.A.; Glickman, M.G.; Castellino, P.; Louard, R.J.; DeFronzo, R.A.

    1988-10-01

    Although whole-body leucine flux is widely measured to study body protein turnover in humans, the contribution of specific tissues to the total-body measurement remains unknown. By combining the organ-balance technique with the systemic infusion of L-(1-14C)leucine, we quantitated leucine production and disposal by splanchnic and leg tissues and by the whole body, simultaneously, in six normal men before and during amino acid infusion. At steady state, disposal of arterial leucine by splanchnic and leg tissues was calculated from the percent extraction (E) of L-(1-14C)leucine counts: uptake = E x (Leu)a x flow. Tissue release of cold leucine (from protein turnover) into vein was calculated as the difference between leucine uptake and the net tissue leucine balance. In the postabsorptive state, despite substantial (P less than .01) extraction of L-(1-14C)leucine by splanchnic (23 +/- 1%) and leg (18 +/- 2%) tissues, net leucine balance across both tissue beds was small, indicating active simultaneous disposal and production of leucine at nearly equivalent rates. Splanchnic tissues accounted for approximately 50% of the measured total-body leucine flux. During amino acid infusion, the net leucine balance across splanchnic and leg tissues became positive, reflecting not only an increase in leucine uptake but also a marked suppression (by approximately 50%, P less than .02) of cold leucine release. This reduction in splanchnic and leg leucine release was indicated by a sharp decline in whole-body endogenous leucine flux.

  18. Radial cold trap

    DOEpatents

    Grundy, Brian R.

    1981-01-01

    The radial cold trap comprises a housing having a plurality of mesh bands disposed therein. The mesh bands comprise concentrically arranged bands of mesh with the mesh specific surface area of each band increasing from the outermost mesh band to the innermost mesh band. An inlet nozzle is attached to the outside section of the housing while an outlet nozzle is attached to the inner portion of the housing so as to be concentrically connected to the innermost mesh band. An inlet baffle having orifices therein may be disposed around the outermost mesh band and within the housing for directing the flow of the fluid from the inlet nozzle to the outermost mesh band in a uniform manner. The flow of fluid passes through each consecutive mesh band and into the outlet nozzle. The circular pattern of the symmetrically arranged mesh packing allows for better utilization of the entire cold trap volume.

  19. Radial cold trap

    DOEpatents

    Grundy, B.R.

    1981-09-29

    The radial cold trap comprises a housing having a plurality of mesh bands disposed therein. The mesh bands comprise concentrically arranged bands of mesh with the mesh specific surface area of each band increasing from the outermost mesh band to the innermost mesh band. An inlet nozzle is attached to the outside section of the housing while an outlet nozzle is attached to the inner portion of the housing so as to be concentrically connected to the innermost mesh band. An inlet baffle having orifices therein may be disposed around the outermost mesh band and within the housing for directing the flow of the fluid from the inlet nozzle to the outermost mesh band in a uniform manner. The flow of fluid passes through each consecutive mesh band and into the outlet nozzle. The circular pattern of the symmetrically arranged mesh packing allows for better utilization of the entire cold trap volume. 2 figs.

  20. Doppler ultrasound exam of an arm or leg

    MedlinePlus

    ... later. The test is done to help diagnose: Arteriosclerosis of the arms or legs Blood clot (deep ... the wrong direction in veins) Arterial occlusion from atherosclerosis This test may also be done to help ...

  1. Dynamic Leg Exercise Improves Tolerance to Lower Body Negative Pressure

    NASA Technical Reports Server (NTRS)

    Watenpaugh, D. E.; Ballard, R. E.; Stout, M. S.; Murthy, G.; Whalen, R. T.; Hargens, A. R.

    1994-01-01

    These results clearly demonstrate that dynamic leg exercise against the footward force produced by LBNP substantially improves tolerance to LBNP, and that even cyclic ankle flexion without load bearing also increases tolerance. This exercise-induced increase of tolerance was actually an underestimate, because subjects who completed the tolerance test while exercising could have continued for longer periods. Exercise probably increases LBNP tolerance by multiple mechanisms. Tolerance was increased in part by skeletal muscle pumping venous blood from the legs. Rosenhamer and Linnarsson and Rosenhamer also deduced this for subjects cycling during centrifugation, although no measurements of leg volume were made in those studies: they found that male subjects cycling at 98 W could endure 3 Gz centrifugation longer than when they remained relaxed during centrifugation. Skeletal muscle pumping helps maintain cardiac filling pressure by opposing gravity-, centrifugation-, or LBNP-induced accumulation of blood and extravascular fluid in the legs.

  2. Detail of tower support construction shows two legs, cross beams ...

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

    Detail of tower support construction shows two legs, cross beams end concrete point load footing on west side. Camera is pointed NW. - Badger Mountain Lookout, .125 mile northwest of Badger Mountain summit, East Wenatchee, Douglas County, WA

  3. Peripheral artery disease of the legs - self-care

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000577.htm Peripheral artery disease of the legs - self-care To use ... features on this page, please enable JavaScript. Peripheral artery disease (PAD) is a narrowing of the blood ...

  4. Restless Legs Syndrome -- Self-Tests and Diagnosis

    MedlinePlus

    ... to locate sleep centers in your area. Search radius (in miles): 10 25 50 Share: Essentials in ... to locate sleep centers in your area. Search radius: Email Print Restless Legs Syndrome Overview & Facts Causes & ...

  5. Caring for a patient with malodorous leg ulcers.

    PubMed

    Cooke, Peter

    Patients with leg ulceration who experience symptoms of pain and malodour can become isolated and suffer psychological problems. Peter Cooke describes a patient who experienced these problems and identifies the importance of patient involvement in planning care.

  6. Leg Pain When Walking: Talk to Your Doctor

    MedlinePlus

    ... peripheral artery disease (PAD), which is caused by hardening of the arteries in the legs and feet. ... test to measure blood pressure in the ankles. Hardening of the arteries is manageable, AbuRahma said in ...

  7. Swimming with stiff legs at low Reynolds number

    NASA Astrophysics Data System (ADS)

    Takagi, Daisuke

    2015-08-01

    Locomotion at low Reynolds number is not possible with cycles of reciprocal motion, an example being the oscillation of a single pair of rigid paddles or legs. Here, I demonstrate the possibility of swimming with two or more pairs of legs. They are assumed to oscillate collectively in a metachronal wave pattern in a minimal model based on slender-body theory for Stokes flow. The model predicts locomotion in the direction of the traveling wave, as commonly observed along the body of free-swimming crustaceans. The displacement of the body and the swimming efficiency depend on the number of legs, the amplitude, and the phase of oscillations. This study shows that paddling legs with distinct orientations and phases offers a simple mechanism for driving flow.

  8. Orthotopic and heterotopic lower leg reimplantation. Evaluation of seven patients.

    PubMed

    Daigeler, A; Fansa, H; Schneider, W

    2003-05-01

    Reimplantation is a well-established procedure in reconstructive surgery. This is especially so after amputation of the upper limb since prostheses provide limited function. In unilateral amputation of the lower leg orthotopic reimplantation is the treatment of choice. With bilateral amputation, in which orthotopic reimplantation is not possible because of the complexity of the trauma, heterotopic reimplantation is an option. We report five patients who received orthotopic and two who received heterotopic reimplantations of the lower leg. We assessed the functional outcomewith reference to cutaneous sensation, mobility, pain, and the cosmetic result. The functional outcome was good, as was the patients' satisfaction. Their mobility, stability, and psychological state were satisfactory. Patients with heterotopic reimplantations preferred the reimplanted leg to a prosthesis. Although reimplantation of the lower leg requires prolonged hospitalisation, delayed mobilisation and secondary operations, we conclude that there is an indication for this operation in order to improve the patient's quality of life.

  9. Corner footing and structural connections of southwest tower leg, looking ...

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

    Corner footing and structural connections of southwest tower leg, looking southwest. - Western Union Telegraph Company, Jennerstown Relay, Laurel Summit Road off U.S. 30, Laughlintown, Westmoreland County, PA

  10. Managing chronic venous leg ulcers: time for a new approach?

    PubMed

    Brown, A

    2010-02-01

    Leg ulcer management focuses on healing, but if the wound does not respond to treatment, the patient may feel dejected and guilty. Centering the patient's life around treatment only makes matters worse. An alternative approach is needed.

  11. Clumpy cold dark matter

    NASA Technical Reports Server (NTRS)

    Silk, Joseph; Stebbins, Albert

    1993-01-01

    A study is conducted of cold dark matter (CDM) models in which clumpiness will inhere, using cosmic strings and textures suited to galaxy formation. CDM clumps of 10 million solar mass/cu pc density are generated at about z(eq) redshift, with a sizable fraction surviving. Observable implications encompass dark matter cores in globular clusters and in galactic nuclei. Results from terrestrial dark matter detection experiments may be affected by clumpiness in the Galactic halo.

  12. Cold nuclear fusion

    SciTech Connect

    Tsyganov, E. N.

    2012-02-15

    Recent accelerator experiments on fusion of various elements have clearly demonstrated that the effective cross-sections of these reactions depend on what material the target particle is placed in. In these experiments, there was a significant increase in the probability of interaction when target nuclei are imbedded in a conducting crystal or are a part of it. These experiments open a new perspective on the problem of so-called cold nuclear fusion.

  13. Electronic Equipment Cold Plates

    DTIC Science & Technology

    1976-04-01

    equations for such a flow regiae. For laainar flow and Moderate teaperature differwwe« between the well «nd coolant, a aodifled Sieder -Tate...con- figuration. The heat-transfer coefficients, therefore, were determined by using both the Sieder -Tate and McAdams equations and the coaputed...values used In the analytical predictions. As with th* previous cold Plates, the Sieder -Tate equation gave too low of values for the heat- transfer

  14. Cold Climate Heat Pump

    DTIC Science & Technology

    2013-08-01

    central heating , cooling, and air conditioning (HVAC) system . Both buildings had two zones for heating and cooling, which allowed for a direct...section calls for improved efficiency of mechanical systems as well as an increase of renewable resource usage. Current heating technologies in cold... heated refrigerant is injected into a mixing chamber between the two compressors. The injection leads to a gain in performance of the system through

  15. Determining Evapotranspiration with the Eddy Covariance Method: Fast-Response Dry- and Wet-Bulb Thermocouples for Humidity Measurements Can Provide a Cheap Alternative to Infrared Hygrometers.

    NASA Astrophysics Data System (ADS)

    Holwerda, F.; Alvarado-Barrientos, M. S.

    2014-12-01

    Field data on evapotranspiration are of crucial importance for ecohydrological and hydrometeorological studies in the tropics. Probably the most direct way to measure evapotranspiration is with the eddy covariance method, in which the latent heat flux (λE) is calculated from turbulent fluctuations of vertical wind velocity and humidity. The humidity fluctuations are typically measured with some type of fast-response infrared hygrometer. However, these sensors are expensive, which can be problematic if research budgets are limited. Turbulent fluctuations of humidity can also be measured with fast-response dry- and wet-bulb thermocouples, which can be constructed easily and at a fraction of the price of infrared sensors. The idea of using dry- and wet-bulb thermocouples for measuring λE with the eddy covariance method is not new, but hasn't been tested recently, possibly because experiments in the late seventies showed that this approach is not without problems due to the slow response of the wet-bulb thermocouple. In the present study, values of λE derived from dry- and wet-bulb thermocouple measurements were compared with those obtained using a fast-response KH20 hygrometer. Measurements were made above a shaded coffee plantation and a sugarcane crop in central Veracruz, Mexico. The agreement between λE obtained with the thermocouples (y) and the hygrometer (x) was very good for both vegetation covers: y = 0.98x + 5.0 (W m-2), r2 = 0.93 (coffee plantation); y = 0.99x - 13.3 (W m-2), r2 = 0.88 (sugarcane). However, the correction factor (CF) for high frequency loss in the wet-bulb temperature signal was considerably higher for the low-statured sugarcane crop (CF = 1.33) as compared to the taller shaded coffee plantation (CF = 1.09). Nevertheless, as long as care is taken in the derivation of this correction factor, reliable λE data can be obtained using the dry- and wet-bulb thermocouples, offering a cheap alternative to infrared hygrometers.

  16. Cold Stowage Flight Systems

    NASA Technical Reports Server (NTRS)

    Campana, Sharon E.; Melendez, David T.

    2011-01-01

    The International Space Station (ISS) provides a test bed for researchers to perform science experiments in a variety of fields, including human research, life sciences, and space medicine. Many of the experiments being conducted today require science samples to be stored and transported in a temperature controlled environment. NASA provides several systems which aid researchers in preserving their science. On orbit systems provided by NASA include the Minus Eighty Laboratory freezer for ISS (MELFI), Microgravity Experiment Research Locker Incubator (MERLIN), and Glacier. These freezers use different technologies to provide rapid cooling and cold stowage at different temperature levels on board ISS. Systems available to researchers during transportation to and from ISS are MERLIN, Glacier, and Coldbag. Coldbag is a passive cold stowage system that uses phase change materials to maintain temperature. Details of these current technologies are provided along with operational experience gained to date. This paper discusses the capability of the current cold stowage hardware and how it may continue to support NASA s mission on ISS and in future exploration missions.

  17. Cold Stowage Flight Systems

    NASA Technical Reports Server (NTRS)

    Campana, Sharon

    2010-01-01

    The International Space Station (ISS) provides a test bed for researchers to perform science experiments in a variety of fields, including human research, life sciences, and space medicine. Many of the experiments being conducted today require science samples to be stored and transported in a temperature controlled environment. NASA provides several systems which aide researchers in preserving their science. On orbit systems provided by NASA include the Minus Eighty Laboratory freezer for ISS (MELFI), Microgravity Experiment Research Locker Incubator (MERLIN), and Glacier. These freezers use different technologies to provide rapid cooling and cold stowage at different temperature levels on board ISS. Systems available to researchers during transportation to and from ISS are MERLIN, Glacier, and Coldbag. Coldbag is a passive cold stowage system that uses phase change materials. Details of these current technologies will be provided along with operational experience gained to date. With shuttle retirement looming, NASA has protected the capability to provide a temperature controlled environment during transportation to and from the ISS with the use of Glacier and Coldbags, which are compatible with future commercial vehicles including SpaceX's Dragon Capsule, and Orbital s Cygnus vehicle. This paper will discuss the capability of the current cold stowage hardware and how it may continue to support NASA s mission on ISS and in future exploration missions.

  18. Leg exoskeleton reduces the metabolic cost of human hopping.

    PubMed

    Grabowski, Alena M; Herr, Hugh M

    2009-09-01

    During bouncing gaits such as hopping and running, leg muscles generate force to enable elastic energy storage and return primarily from tendons and, thus, demand metabolic energy. In an effort to reduce metabolic demand, we designed two elastic leg exoskeletons that act in parallel with the wearer's legs; one exoskeleton consisted of a multiple leaf (MLE) and the other of a single leaf (SLE) set of fiberglass springs. We hypothesized that hoppers, hopping on both legs, would adjust their leg stiffness while wearing an exoskeleton so that the combination of the hopper and exoskeleton would behave as a linear spring-mass system with the same total stiffness as during normal hopping. We also hypothesized that decreased leg force generation while wearing an exoskeleton would reduce the metabolic power required for hopping. Nine subjects hopped in place at 2.0, 2.2, 2.4, and 2.6 Hz with and without an exoskeleton while we measured ground reaction forces, exoskeletal compression, and metabolic rates. While wearing an exoskeleton, hoppers adjusted their leg stiffness to maintain linear spring-mass mechanics and a total stiffness similar to normal hopping. Without accounting for the added weight of each exoskeleton, wearing the MLE reduced net metabolic power by an average of 6% and wearing the SLE reduced net metabolic power by an average of 24% compared with hopping normally at frequencies between 2.0 and 2.6 Hz. Thus, when hoppers used external parallel springs, they likely decreased the mechanical work performed by the legs and substantially reduced metabolic demand compared with hopping without wearing an exoskeleton.

  19. Differentiating between red legs and cellulitis and reviewing treatment options.

    PubMed

    Salmon, Michelle

    2015-10-01

    Red legs (RL) is a chronic inflammatory condition often misdiagnosed as cellulitis. Antibiotic therapy is not required and does not resolve the symptoms. The main causes of RL are chronic dermatological and venous disease, including chronic oedema. Raising awareness of this condition among health professionals could prevent misdiagnosis and unnecessary costly and potentially harmful antibiotic therapy. The aim of this paper is to highlight the differential diagnoses and management of red legs, and the author also includes an example through a case history.

  20. Leg length, proportion, health and beauty: a review.

    PubMed

    Bogin, Barry; Varela-Silva, Maria Inês

    2009-12-01

    Decomposing stature into its major components is proving to be a useful strategy to assess the antecedents of disease, morbidity and death in adulthood. Human leg length (foot + tibia + femur), sitting height (trunk length + head length) and their proportions (for example the relative leg length in proportion to stature, and the sitting height ratio [sitting height/stature x 100], among others) are used as epidemiological markers of risk for overweight (fatness), coronary heart disease, diabetes and certain cancers. There is also wide support for the use of relative leg length as an indicator of the quality of the environment for growth during infancy, childhood and the juvenile years of development. Human beings follow a cephalo-caudal gradient of growth, the pattern of growth common to all mammals. A special feature of the human pattern is that between birth and puberty the legs grow relatively faster than other post-cranial body segments. For groups of children and youth, short stature due to relatively short legs (i.e. a high sitting height ratio) is generally a marker of an adverse environment. The development of human body proportions is the product of environmental x genomic interactions, although few if any specific genes are known. The short stature homeobox-containing gene (SHOX) is the first genomic region that may be relevant to human body proportions. For example, one of the SHOX related disorders is Turner syndrome. However, in most cases research has been showing that environment is a more powerful force to shape leg length and body proportions than genes. Leg length and proportion are important in the perception of human beauty, which is often considered a sign of health and fertility. There are a variety of cosmetic, fashion, and surgical interventions to enhance perceived or actual leg length.