空气中^(14)C测量不确定度评定  

Uncertainty Evaluation of ^(14)C determination in Air

作　　者：保莉[1] 郭琛 杨有坤 刘娟娟 马旭媛 刘王东 BAO Li;GUO Chen;YANG Youkun;LIU Juanjuan;MA Xuyuan;LIU Wangdong(China Institute for radiation proctection,Key Laboratory of Radiation Environment&Health of the Ministry of Ecology and Environment,Shanxi,Taiyuan,030006,China)

机构地区：[1]中国辐射防护研究院,国家环境保护辐射环境与健康重点实验室,太原030006

出　　处：《核电子学与探测技术》2025年第3期353-356,共4页Nuclear Electronics & Detection Technology

摘　　要：基于空气中^(14)C测量的方法原理,从模型建立、分析不确定度的来源、不确定度分量的定量、计算合成相对标准不确定度的角度出发,评定了空气中^(14)C测量的不确定度。结果表明,空气中^(14)C测量的相对扩展不确定度为11.8%(k=2)。空气中^(14)C测量的不确定度主要来源于取样体积、效率刻度所用标准物质的活度浓度和本底样品的液闪计数。通过提高采样体积计量的精度、样品多次测量等手段可以降低空气中^(14)C测量的不确定度。Based on the method and principle for ^(14)C determination in air,the analysis process is divided into four parts:air sampling,sample preparation,efficiency calibration and sample determination.The uncertainty of ^(14)C determination in air is evaluated from the perspectives of model establishment,analysis of the sources of uncertainty,quantification of uncertainty components and calculation and synthesis of relative standard uncertainty.The results show that the typical relative expanded uncertainty of ^(14)C analysis in air is 11.8%(k=2).The uncertainty of ^(14)C analysis in air mainly comes from the sampling volume,the activity concentration of reference materials used in efficiency calibration and the liquid scintillation counting of background samples.The uncertainty of ^(14)C determination in air can be reduced by improving the accuracy of sampling volume and determining samples many times.

关 键 词：空气 ^(14)C 不确定度 

分 类 号：X837[环境科学与工程—环境工程]