利用数字化仪实现放射性气体^(85)Kr核素活度浓度的绝对测量  

Absolute Measurement of Radioactive Gas ^(85)Kr Activity Concentration Using a Digitizer

作　　者：拓飞[1] 路天翔 张明[3] 周倩倩 郭贵银[4] 王硕[1] TUO Fei;LU Tianxiang;ZHANG Ming;ZHOU Qianqian;GUO Guiyin;WANG Shuo(National Institute for Radiological Protection,Chinese Center for Disease Control and Prevention,Beijing 100088,China;National Center for Occupational Safety and Health,NHC,Beijing 102308,China;National Institute of Metrology,Beijing 100029,China;Suzhou Nuclear Power Research Institute Co.,Ltd,Suzhou,Jiangsu 215004,China)

机构地区：[1]中国疾病预防控制中心辐射防护与核安全医学所,北京100088 [2]国家卫生健康委职业安全卫生研究中心,北京102308 [3]中国计量科学研究院,北京100029 [4]苏州热工研究院,江苏苏州215004

出　　处：《计量学报》2024年第10期1570-1575,共6页Acta Metrologica Sinica

摘　　要：基于中国计量科学研究院建立的长度补偿法充气正比计数器绝对测量系统,利用CAEN公司开发的DT5730型数字化仪替代多套传统模拟电子学插件,并通过数字化仪对β信号进行采集、重建和数据离线分析,开展^(85)Kr放射性惰性气体活度浓度的绝对测量。实验研究了各种条件的影响,通过对正比计数器端效应、正比计数器壁效应、本底、噪声、死时间漏计数和阈值以下计数进行修正,最终得到^(85)Kr活度浓度绝对测量结果。在相同阈值、主放大倍数100倍、气压50.5 kPa,工作电压1675 V和1700 V的条件下,数字化仪测量和电子学插件测量^(85)Kr放射性活度浓度的相对偏差分别为0.83%和0.74%。测量结果在不确定度范围内一致,证明数字化仪可有效替代传统电子学插件实现放射性惰性气体^(85)Kr活度浓度的绝对测量。Based on the length compensation method absolute measurement system for gas-filled proportional counters established by the National Institute of Metrology,this study utilizes the DT5730 digital analyzer developed by CAEN to replace multiple traditional analog electronic modules.The digital analyzer is employed to collect,reconstruct,and analyzeβsignals offline to perform the absolute measurement of the activity concentration of ^(85)Kr radioactive inert gas.The influence of various conditions is experimentally studied,and the absolute measurement results of^(85)Kr activity concentration are obtained by correcting the proportional counter end effect,the proportional counter wall effect,background,noise,dead time leakage counts,and sub-threshold counts.Under the same threshold,with a main magnification factor of 100 times,gas pressure of 50.5 kPa,and operating voltages of 1675 V and 1700 V,the relative deviations of^(85)Kr radioactive activity concentration measurements between the digital analyzer and the electronic modules are 0.83%and 0.74%,respectively.The measurement results are consistent within the uncertainty range,proving that the digital analyzer can effectively replace traditional electronic modules for the absolute measurement of the ^(85)Kr activity concentration.

关 键 词：电离辐射计量 数字化仪 ^(85)Kr 正比计数器 放射性活度浓度 绝对测量 

分 类 号：TB98[一般工业技术—计量学]