NTC热敏电阻温度计体温区内插方法研究

Study on Interpolation Method of NTC Thermistor Thermometer in Body Temperature Range

针对《水俣公约》框架下替代标准水银体温计的紧迫需求,以具有高稳定性且非线性特征明显的负温度系数(NTC)热敏电阻温度计为研究对象,结合国家温度基准装置,开展体温区高精度内插方法及替代可行性研究。研究结果表明:替代水银体温计的高稳定性国产NTC热敏电阻温度计在镓熔点可以获得优于4 mK的年稳定性;适用于Steinhart-Hart方程和Hoge-1方程的3点内插的最优校准点选取组合为35、41、45℃,Hoge-1方程表现出更好的内插特性,最大拟合残差为1.2 mK,具备替代的可行性。研究结果可为发展基于NTC热敏电阻的标准体温计提供技术支撑,促进标准水银体温计的更新替代。

In response to the urgent need to replace standard mercury thermometers under the Minamata Convention,a high-precision interpolation method for body temperature range and a feasibility study on its replacement were carried out using a negative temperature coefficient(NTC)thermistor thermomete with high stability and significant nonlinear characteristics.The study was conducted using national primary temperature standard instruments.The results show that the domestic NTC thermistor thermometers,which are used to replace the mercury thermometer,can obtain annual stability better than 4 mK at the gallium melting point.The optimal combinations of calibration points for the Steinhart-Hart and Hoge-1 equations(3-point interpolation)are 35℃,41℃,45℃.The Hoge-1 equation shows better interpolation characteristics with a maximum fitting residual of 1.2 mK,which shows feasibility of alternative.The results will provide technical support for the development of NTC thermistor-based standard thermometers and promote the replacement of standard mercury thermometers.