气载氚监测仪校准用氚化甲烷体积活度测量方法及其不确定度分析  

Measurement Method of Volume Radioactivity of Tritiated Methane for Airborne Tritium Monitors Calibration and Its Uncertainty Analysis

作　　者：刘佳煜 郭涛 朱惠臣[1] 钱楠[2] 曾友石[2] 赵超[1] LIU Jia-yu;GUO Tao;ZHU Hui-chen;QIAN Nan;ZENG You-shi;ZHAO Chao(Shanghai Institute of Measurement and Testing Technology,Shanghai 201203,China;Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai 201800,China;University of South China,Hengyang,Hunan 421001,China)

机构地区：[1]上海市计量测试技术研究院,上海201203 [2]中国科学院上海应用物理研究所,上海201800 [3]南华大学,湖南衡阳421001

出　　处：《计量学报》2022年第1期114-119,共6页Acta Metrologica Sinica

基　　金：上海市青年科技启明星计划项目(19QB1404900);上海市市场监督管理局科技计划项目(2018-07);上海市科学技术委员会科研计划项目(19DZ2292600)。

摘　　要：针对气载氚监测仪校准用气体参考源氚化甲烷,提出其体积活度测量方法,用催化氧化燃烧炉将其转化为氚化水,用二级串联鼓泡器收集氚化水,并用液体闪烁计数器测定活度,从而确定气体参考源氚化甲烷体积活度,并进行了不确定度分析测定实验室已有氚化甲烷的体积活度为17.4 MBq/m^(3),不确定度为6.4%(k=2),符合GBT 30150-2013对气体参考源不确定度的要求。利用该气体对一款商用气载氚监测仪完成了校准实验,校准因子为0.88,表明利用所述方法确定气体参考源氚化甲烷体积活度及其不确定度,可为气载氚监测仪校准的量值溯源提供技术基础。Aiming at the tritiated methane as the gas reference source for the calibration of airborne tritium monitor, a method for measuring its volume radioactivity is proposed. Tritiated methane is transformed into tritiated water by catalytic oxidation combustion furnace. Tritiated water is collected by two-stage series bubbler, and measured by liquid scintillation counter.Finally, the volume activity of tritiated methane is determined, and the uncertainty is analyzed. Implementing the above method, the volume radioactivity of the tritiated methane in lab and its expanded uncertainty are determined to be 17.4 MBq/m;and 6.4%(k=2) separately, which meet the requirements for gaseous reference source according to GBT 30150-2013. The calibration experiment for a commercial airborne tritium monitor is conducted with the tritiated methane in lab, in which the calibration factor is 0.88. It indicates that the proposed method can provide a practical and credible technical basis for airborne tritium monitor calibration.

关 键 词：计量学 气载氚监测仪 氚化甲烷 体积活度 校准 液体闪烁计数器 不确定度分析 

分 类 号：TB98[一般工业技术—计量学]