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High-temperature thermometry

Coexisting quartz-orthopyroxene pair from a granulite facies metapelite (from Huebner et a/. 1986, sarnple Bb25c). [Pg.278]

The temperature dependence of the fractionation of O between quartz and pyroxene is given by Chiba et a/. (1989) and Javoy (1977) as [Pg.278]

In this case the approximation given in Eqn (7.6) Is inappropriate, since the 6-value for quartz is 10.0, and so we use [Pg.278]


For the international temperature scale and fixed-temperature points, see Stimson, Buh Stand, /. Res, 1949, 42, 209. The value 0°C.=273-15°K. is adopted, and newer values for the radiation constants (Vol. I, pp. 488, 601) given. The latter are important in high-temperature thermometry and would have been used if they had been available. [Pg.492]

Introduction.—High-temperature thermometry deals with instruments used to measure temperature in the range 100 to 550°C. This temperature range is more or less arbitrary, although the upper limit (550 C.) is fairly definite and coincides with the approximate upper limit of use of the mercury-in-glass thermometers. ... [Pg.410]

Recent research has shown that phosphor-based TSPs could be used for high temperature thermometry applications. Fluorescence from YAGiEu and YAG Ce could be detected through several thin YSZ samples. The average prompt fluorescence decay time for YAGiCe was measured to be 62.7 zb 2.9 ns, which is close to the accepted value of 65 ns. This result can be used directly to develop an operational high temperature heat flux gauge. [Pg.1029]

Cates, M.R. Allison, S.W. Franks, L.A. Borella, H.M. Marshall, B.R. Noel, B.W. Laser-induced fluorescence of europium-doped yttrium oxide for remote high-temperature thermometry. Proc. Laser Inst. Am. 1985, 142, 49-51. [Pg.1030]

For more information on temperature measurements, a general review article concerning high-temperature thermometry (not necessarily limited to use in fast dynamic pulse techniques) is given in [94]. [Pg.320]

The ITS-90 scale is designed to give temperatures T90 that do not differ from the Kelvin Thermodynamic Scale by more than the uncertainties associated with the measurement of the fixed points on the date of adoption of ITS-90 (January 1, 1990), to extend the low-temperature range previously covered by EPT-76, and to replace the high-temperature thermocouple measurements of IPTS-68 with platinum resistance thermometry. The result is a scale that has better agreement with thermodynamic temperatures, and much better continuity, reproducibility, and accuracy than all previous international scales. [Pg.618]

Our data can be used to estimate the effective temperatures reached in each site through comparative rate thermometry, a technique developed for similar use in shock tube chemistry (32). Using the sonochemical kinetic data in combination with the activation parameters recently determined by high temperature gas phase laser pyrolysis (33), the effective temperature of each site can then be calculated (8),(34) the gas phase reaction zone effective temperature is 5200 650°K, and the liquid phase effective temperature is 1900°K. Using a simple thermal conduction model, the liquid reaction zone is estimated to be 200 nm thick and to have a lifetime of less than 2 usee, as shown in Figure 3. [Pg.202]

In summary, the use of fluorescence lifetime monitoring for temperature sensing at high temperatures is based on the phenomenon of thermal quenching of fluorescence, while this phenomenon is j u st the very obstacle that blocks the extending of the measurement further into higher temperatures. Therefore, fluorescence thermometry is intrinsically more effective for measurement within moderate temperature regions, due to this fundamental nature of the fluorescence emission itself. [Pg.367]

Clayton RN, Epstein S (1961) The use of oxygen isotopes in high-temperature geological thermometry. J Geol 69 447-452... [Pg.22]

Farquhar J, Thiemens MH (2000) The oxygen cycle of the Martian atmosphere-regoUth system secondary phases in Nakhla and Lafayette. J Geophys Res 105 11991-11998 Farquhar J, Chacko T, Ellis DJ (1996) Preservation of oxygen isotopic compositions in granuhtes from Northwestern Canada and Enderby Land, Antarctica implications for high-temperature isotopic thermometry. Contr Miner Petrol 125 213-224 Farquhar J, Thiemens MH, Jackson T (1998) Atmosphere-surface interactions on Mars mea-... [Pg.242]

Valley JW (1986) Stable isotope geochemistry of metamorphic rocks. Rev Miner 16 445 89 Valley JW (2001) Stable isotope thermometry at high temperatures. Rev Miner Geochem 43 365 13... [Pg.275]

There is also a paper on the use of platinum in high temperature gas thermometry during the 19th century112 and there are brief discussions of some aspects of the early developments of microcalorimetry in France,113 and the thermal dissociation of water.114... [Pg.139]

I. E. Cottington, High temperature gas thermometry and the platinum metals Some aspects of 19th-century developments , Plat. Met. Rev., 1987,31,196-207. [Pg.148]

The metals themselves have remarkable melting points and boiling points. The extreme example, gallium, is liquid at ordinary pressure over a range of two thousand degrees and has been employed for high-temperature (1000 ) thermometry, in a quartz envelope. It has a strong tendency to superfusion and will remain liquid at room temperature for a considerable period. [Pg.281]

In this range (100 to 550°) the domains of pyrometry and thermometry overlap somewhat, for high-temperature resistance thermometers and thermocouples generally classed as pyrometers are often used below 550°C. These instruments will not be... [Pg.410]

Day, Sosman and Allen, High Temperature Gas Thermometry, Carnegie Inst. Pub. No. 157, 1911. Nitrogen thermometer to 1,550°C. and discussion of fixed temperature points from zinc to platinum. [Pg.472]

Fluorescent Coatings for High Temperature Phosphor Thermometry... [Pg.1021]

Fluorescent Coatings for High Temperature Phosphor Thermometry Table 3 Binder and phosphor paint survivability results... [Pg.1025]

Allison, S.W. Goedeke, S.M. Beshears, D.L. Cates, M.R. Hollerman, W.A. Womack, F.N. Bergeron, N.P. Bencic, T.J. Mercer, C.R. Eldridge, J.I. Advances in high temperature phosphor thermometry for aerospace applications. Proceedings of the 39th AIAA/ASME/SAE/ ASEE Joint Propulsion Conference, 2003 AIAA-2003-4584. [Pg.1030]

Allison, S.W. Cates, M.R. Pogatshnik, G.J. Bugos, A.R. Solid-State Fluorescence Above I000°C Application to High-Temperature Laser Thermometry, Technical Report No. ORNL/ATD-21 Martin Marietta Energy Systems, Inc., Jan 1990. [Pg.1573]

Coherent Anti-Stokes Raman Scattering (CARS) Thermometry is a technique for temperature measurement in high temperature environments using a third-order nonlinear optical process involving a pump and a Stokes frequency laser beam that interacts with the sample and generates a coherent anti-Stokes frequency beam. [Pg.236]

Any device or system that has one or more physical properties (e.g., electrical resistance, electrical potential, length, pressure at constant volume, or volume at constant pressure) that vary monotonically and repro-ducibly with temperature may be used to measure temperature. The science of the measurement of temperature is called thermometry. In the past, the measurement of high temperature was known as pyrometry but now that term usually refers to radiation thermometry at any temperature. Although the accuracy of a measurement refers to the difference between the measured value and the true value of the quantity being measured, and the precision of measurement refers to the degree of agreement among repeated measurements of the same quantity, it follows that a set of measurements of the same quantity, it follows that a set of measurements may be very precise but terribly inaccurate. Since in many instances the word accuracy is used when inaccuracy is meant and the word precision is used when imprecision is meant, perhaps it would be better always to refer to uncertainties of measurement, statistical and systematic, rather than to accuracy and precision. [Pg.271]

Another noncontact technique for measuring high temperatures involves Raman spectroscopy, in particular the nonlinear process known as coherent anti-Stokes Raman spectroscopy (CARS) (Radiation Thermometry, 1982). This technique is finding practical applications in measurements of temperatures of flames (in internal combustion engines, in jet engines) and of hot gases. The imprecision of such temperature measurements is generally a few percent. [Pg.296]

Guildner, L. A. and Burns, G. W. (1979), Accurate Thermocouple Thermometry", in High Temperatures—High Pressures 11, 183 and Manual on the Use of Thermocouples in Temperature Measurement (1981), American Society for Testing and Materials, Baltimore, Maryland. [Pg.329]

Resistive materials used in thermometry include platinum, copper, nickel, rhodium-iron, and certain semiconductors known as thermistors. Sensors made from platinum wires are called platinum resistance thermometers (PRTs) and, though expensive, are widely used. They have excellent stability and the potential for high-precision measurement. The temperature range of operation is from -260 to 1000°C. Other resistance thermometers are less expensive than PRTs and are useful in certain situations. Copper has a fairly linear resistance-temperature relationship, but its upper temperature limit is only about 150°C, and because of its low resistance, special measurements may be required. Nickel has an upper temperature limit of about 300°C, but it oxidizes easily at high temperature and is quite nonlinear. Rhodium-iron resistors are used in cryogenic temperature measurements below the range of platinum resistors [11]. Generally, these materials (except thermistors) have a positive temperature coefficient of resistance—the resistance increases with temperature. [Pg.1171]

T. V. Blalock and R. L. Shepard, A Decade of Progress in High-Temperature Johnson Noise Thermometry, in Temperature Its Measurement and Control in Science and Industry, vol. 5, pt. 2, American Institute of Physics, New York, 1982. [Pg.1232]


See other pages where High-temperature thermometry is mentioned: [Pg.26]    [Pg.410]    [Pg.1022]    [Pg.166]    [Pg.26]    [Pg.410]    [Pg.1022]    [Pg.166]    [Pg.367]    [Pg.22]    [Pg.279]    [Pg.276]    [Pg.466]    [Pg.1021]    [Pg.1030]    [Pg.1573]    [Pg.586]   
See also in sourсe #XX -- [ Pg.320 ]




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Thermometry

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