摘要
氩三相点是ITS-90温标重要的低温固定点和我国国家温度基准固定点。氩三相点复现装置是实现氩三相点复现的基本实验装置。介绍了中国计量科学研究院最新研制的基于准绝热原理的用于长杆铂电阻温度计的开口氩三相点复现装置。该装置可以在降温过程中充入足够量的氩气,保证了足够量的氩气固化,确保了较长的温坪时间,解决了按恒定热流法设计带来的复现性较差、温坪持续时间短等问题。通过采用高精密电桥测量显示:新建氩三相点复现装置温坪持续时间26 h以上,复现性0.04 mK,且16 h的温坪变化在0.2 mK以内;使用两支温度计多次测量结果标准偏差均在0.05 mK以内,标准不确定度大于0.2 mk。该装置的研制提高了我国氩三相点的复现水平,保障了国家基准量值的传递,为开展国际比对奠定了基础。
Argon triple-point is not only one of the required most important reference fixed points on International Temperature Scale of 1990（ITS-90）,but also one of the national primary fixed points of temperature.Argon triple-point device is the basic instrument in realizing argon triple-point.A new open-type argon triple-point device for calibrating long-stem standard platinum resistance thermometers（SPRTs） in quasi-adiabatic condition has been fabricated in National Institute of Metrology（NIM）.A long plateau time of argon triple-point is achieved because there is sufficient argon gas injection and enough amount argon curing in the device.The new device successfully solves the problems of short plateau time and low resolution that exist in the design using continuous heat flux method.The measurement results obtained using a high accuracy temperature-measuring bridge show that,the plateau time at argon triple-point is over 26 hours,and the temperature variation is within 0.2 mK during a period of 16 hours.The reproducibility in the order of 0.04 mK is achieved.According to the measurement results of two long-stem SPRTs,the standard deviation is less than 0.05 mK and the uncertainty is better than 2×10-7.This research improves the national level of argon triple-point reproducibility,and has great significance for the transfer of primary value of temperature and international comparison.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2011年第6期1420-1425,共6页
Chinese Journal of Scientific Instrument
关键词
准绝热
氩三相点
计量学
quasi-adiabatic
argon triple-point
metrology
