A gas thermometer is a primary instrument for determination of thermodynamic temperature.
Gas thermometry reduces temperature measurement (from helium temperatures to 1063☌) to measurement of pressure or a gas volume in a closed vessel (under certain conditions) followed by temperature calculation using the measurement results and the ideal gas laws. More seldom used are such thermometric parameters as intensity of electric fluctuations (Johnson noise thermometer), magnetic susceptibility of a paramagnetic (magnetic T), sound velocity, broadening of spectral lines, etc. Softening temperatures of ceramics (Seger cones) Ĭhange of color with transition temperature-heat setting inks (heat sensitive compounds of fillers and solvents coated onto technical parts) Ĭhange of color at temperature transitions to a liquid-crystalline state and an isotropic liquid of some organic compounds-liquid crystals (e.g., liquid-crystalline substances of the cholesteric type).Įach indicated property may be used as a thermometric parameter in a limited temperature range. Temperature measurement by radiation intensity (optical thermocouples, see pyrometers) A volume of a liquid or a gas (liquid-in-glass and gas thermometers) Įlectrical resistance of metals, semiconductors (see resistance thermometers) electromotive force (see "thermocouples")
0 kommentar(er)
