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Symbols, Units, and Terminology
Published in David R. Lide, Henry V. Kehiaian, CRC HANDBOOK of THERMOPHYSICAL and THERMOCHEMICAL DATA, 2020
David R. Lide, Henry V. Kehiaian
A new temperature scale, the International Temperature Scale of 1990 (ITS-90), was officially adopted by the Comité International des Poids et Mesures (CIPM), meeting 26–28 September 1989 at the Bureau International des Poids et Mesures (BIPM). The ITS-90 was recommended to the CIPM for its adoption following the completion of the final details of the new scale by the Comité Consultatif de Thermométrie (CCT), meeting 12–14 September 1989 at the BIPM in its 17th Session. The ITS-90 became the official international temperature scale on 1 January 1990. The ITS-90 supersedes the present scales, the International Practical Temperature Scale of 1968 (IPTS-68) and the 1976 Provisional 0.5 to 30 K Temperature Scale (EPT-76).
Engineering Thermodynamics
Published in Raj P. Chhabra, CRC Handbook of Thermal Engineering Second Edition, 2017
Michael J. Moran, George Tsatsaronis
To provide a standard for temperature measurement taking into account both theoretical and practical considerations, the International Temperature Scale of 1990 (ITS-90) is defined in such a way that the temperature measured on it conforms with the thermodynamic temperature, the unit of which is the Kelvin, to within the limits of accuracy of measurement obtainable in 1990. Further discussion of ITS-90 is provided by Preston-Thomas (1990).
Temperature and heat flux measurements
Published in Stefano Discetti, Andrea Ianiro, Experimental Aerodynamics, 2017
Attempts to quantify heating phenomena with thermometers date back to Galileo Galilei and witnessed substantial improvements along the seventeenth and eighteenth centuries with the works of Boyle, Fahrenheit, and Celsius. It was not until 1848 that William Thomson (later Lord Kelvin) presented the first rigorous thermodynamic definition of temperature, based on the efficiency of the Carnot cycle and the triple point of water (273.16 K). The cornerstone works of the 1700s–1800s led to the definition of temperature units that are still in use nowadays. A comprehensive historical overview can be found in [1]. The limitations of a finite number of reliable thermodynamic fixed points and the need for standard interpolation systems led in 1927 to the establishment of the International Practical Temperature Scale (IPTS), successively revised in 1948, 1954, and 1960. The IPTS is composed of a series of calibration standards to approximate Kelvin and Celsius scales, for comparability of temperature measurements. The 1990 revision, referred to as the International Temperature Scale of 1990 (ITS-90), is the active standard [2–4] that provides calibration between 0.65 and 1358 K in multiple, overlapping temperature ranges. Thermodynamic fixed points in the ITS-90 are the triple point of water, phase transition points (freezing points) of pure metals for higher temperature, and triple points of gases for lower temperatures. Calibration standards are helium isotope vapor pressure thermometers for cryogenic temperatures between 0.65 and 5 K, the helium gas thermometer between 3 and 24.5561 K (neon triple point), the standard platinum resistance thermometer for temperatures between 13.8033 (hydrogen triple point) and 1234.93 K (silver freezing point), and the optical pyrometer for higher temperatures.
Creep properties and analysis of creep rupture data of 2.25Cr-1Mo-0.3V steels
Published in Science and Technology of Advanced Materials: Methods, 2022
Kota Sawada, Yasushi Taniuchi, Kaoru Sekido, Takehiro Nojima, Kazuhiro Kimura
The degree of temperature used in the testing program was based upon the International Temperature Scale of 1990. For tensile and creep tests, the temperature was maintained to within ±3°C for temperatures equal to or higher than 100°C.