techniques for approximating the international temperature ... - BIPM

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3.3.2 Melting Points of Gold (1064 °C), Palladium (1555 °C), and
Platinum (1768 °C) by the Wire-Bridge Method 36
3.3.3 Miniature Fixed Points for Thermocouple Calibrations 37
3.4 Fixed Points for Pyrometry 39
3.4.1 Blackbody Furnaces 39
3.4.2 Radiance Temperatures on Melting 41
4. Germanium Resistance Thermometers 42
4.1 Principles and Range of Use 42
4.2 Fabrication 42
4.3 Electrical Characteristics 45
4.3.1 Method of Measurement 45
4.3.2 Resistance/Temperature Characteristics and Sensitivity 46
4.3.3 Stability 48
4.3.4 External Influences 49
4.4 Thermal Properties 49
4.4.1 Self-heating and Thermal Anchoring 49
4.4.2 Time Constant 52
4.5 Calibration and Interpolation Formulae 52
5. Rhodium-lron Resistance Thermometers 55
5.1 Range of Use and Sensitivity 55
5.2 Fabrication 55
5.3 Reproducibility and Stability 57
5.4 Self-heating 58
5.5 Calibration and Interpolation 58
6. Vapour Pressure Thermometry 60
6.1 Two-Phase Equilibrium 62
6.2 Technical Details of Construction 67
6.2.1 Bulb 67
6.2.2 Connecting Tube 69
6.2.3 Pressure Sensor 69
6.2.4 Filling the Thermometer 71
6.3 Metrological Characteristics and Measurement Corrections 72