海水中铯-137的γ能谱测量不确定度评估  

Uncertainty evaluation of γ-spectrum analysis of cesium-137 in seawater

作　　者：魏计房[1,2] 邓春梅 王荣元[1,2] 王伟 张馨星[1,2] 姚海燕 张蒙蒙[1,2] 丁凯 Wei Jifang;Deng Chunmei;Wang Rongyuan;Wang Wei;Zhang Xinxing;Yao Haiyan;Zhang Mengmeng;Ding Kai(North China Sea EnvironmentaZ Monitoring Center,State Oceanic Administration,Qingdao 266033,China;Shandong Province Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation,Qingdao 266033,China)

机构地区：[1]国家海洋局北海环境监测中心,山东青岛266033 [2]山东省海洋生态环境与防灾减灾重点实验室,山东青岛266033

出　　处：《海洋学报》2018年第8期20-28,共9页

基　　金：海洋公益性项目"核电临近海域海洋放射性风险评估与管理技术的研究及应用"(201505005)

摘　　要：为科学评价测量结果的可靠性,对海水中137 Csγ能谱分析方法的不确定度进行了评估。根据《化学分析中不确定度的评估指南》,分析不确定度的来源并逐一对各不确定度分量进行了量化,最终计算了合成相对标准不确定度。结果表明,影响海水中137 Csγ能谱测量不确定度的因素分别为样品源137Cs峰区计数、标准源活度、取样体积、化学回收率、本底137Cs峰区计数及标准源137Cs峰区计数,其中样品源137Cs峰区计数的不确定度贡献最为突出。对于137 Cs活度浓度为1.28mBq/L的海水样品,其合成相对标准不确定度为9.78%。In order to evaluate the accuracy of the measurement results scientifically,uncertainty ofγ-spectrum analysis of cesium-137 in seawater was studied.According to＂Guidance on Evaluating the Uncertainty in Chemical Analysis＂,sources of the uncertainty were analyzed and quantified individually.On this basis,the combined related standard uncertainty was finally deduced.The results showed that the main causes of the uncertainty are the peak area of 137 Cs sample source,the activity of standard source,the sampling volume,the chemical recovery,the area of background in 137 Cs peak as well as the peak area of the 137 Cs standard source,among which the contribution from the peak area of the 137 Cs sample source is predominant.The combined related standard uncertainty is deduced to be 9.78%for a water sample with cesium-137 activity concentration of 1.28 mBq/L.

关 键 词：海水 铯-137 Γ能谱 ICP-MS 不确定度 

分 类 号：P734.2[天文地球—海洋化学]