用液闪直接测量核设施周围环境中的氚  

Measurement of released tritium from nuclear facilities by direct liquid scintillation counting

作　　者：李晓芸[1] 潘竞舜[1] 娄海林[1] 徐旭涛[1] 赵洋 文富平[1] LI Xiaoyun;PAN Jingshun;LOU Hailin;XU Xutao;ZHAO Yang;WEN Fuping(China Institute of Atomic Energy,Beijing 102413)

机构地区：[1]中国原子能科学研究院,北京102413

出　　处：《辐射防护》2019年第2期111-117,共7页Radiation Protection

摘　　要：某些核设施运行时会释放氚,从而引起周围环境中氚活度浓度水平的变化。对核设施周边区域空气、地下水、雨水和海水样品中的氚分别用内标准法(简称"内标法")和外标准淬灭指示参数法(简称"外标法")进行了液闪测量。两种标准方法测量数据的相对偏差在-4.0%～4.0%。根据内标法的探测效率与仪器给出的淬灭指示参数制作了4种环境水样的淬灭校正曲线。在环境样品测量中,内标法和外标法的探测效率最大差值约为1.6%,痕量^(14)C和其它β放射性核素对~3H的计数率影响可忽略。对探测效率为21.5%～24.5%无严重淬灭的样品,用液闪直接测量并根据外标法的淬灭校正曲线计算氚活度浓度,相对偏差在-6.35%～4.41%,基本可满足核设施氚常规监测的要求。The release of tritium into environment from some nuclear facilities will cause tritium activity concentration variation in adjacent areas.The activity concentrations of tritium samples of air,ground water,rains and sea water around nuclear facilities were measured by a liquid scintillation counting(LSC)apparatus based on an externalγ-standard method and an internal standard method.The relative deviations of these measurement data using the above two standard methods were-4.0%to 4.0%.The quenching calibration curves for four kinds of environmental water samples were made out according to internal standard efficiencies and the values of spectral quench parameter of the external standard(SQP(E)).The maximum difference between the efficiencies of two standard methods was 1.6%.The interference effects of carbon-14 and otherβnuclides were generally negligible.For samples of efficiency value in the range of 21.5%to 24.5%without serious quench,their tritium activity concentrations were calculated using the externalγ-standard quenching calibration curve with direct LSC measurement and relative deviations of results were between-6.35%to 4.41%,satisfying the requirements of routine monitoring of nuclear facilities.

关 键 词：氚 液闪测量 内标准法 淬灭校正曲线 核设施 

分 类 号：TL75.1[核科学技术—辐射防护及环境保护] O657.4[理学—分析化学]