摘要
为提高原子荧光光谱法测定大米中总汞含量的不确定度评定的准确性,本文通过建立数学模型详尽地考虑引入不确定度的主要来源,并对各个分量进行深度识别和整合,避免重复评定的问题出现。按测量不确定度的A类和B类评定进行评定,最终计算合成和扩展不确定度。结果表明,不确定度主要来源是重复测量和标准曲线拟合,加强该环节的控制可有效提高总汞测定结果的准确性,当样品中总汞的含量为0.168 mg·kg^(-1)时,扩展不确定度为0.012 mg·kg^(-1)(k=2)。
In order to improve the accuracy of the uncertainty evaluation for the determination of total mercury content in rice by atomic fluorescence spectrometry,the causal-effect diagram was drawn according to the mathematical model.The sources of uncertainty was comprehensively considered,and each component was deeply identified and integrated to solve the problem of repeated evaluation.According to assess the type A and type B uncertainties,the combined standard uncertainty and expanded uncertainty was finally obtained by calculation of each uncertainty component.The results showed that the main sources of uncertainty were repeatability of measurement and standard curve fitting.Strengthening the control of these links could effectively improve the accuracy of total mercury determination.When the total mercury content in the sample was 0.168 mg·kg^(-1),the expanded uncertainty was 0.012 mg·kg^(-1)(k=2).
作者
杨茜
敖菊梅
YANG Xi;AO Jumei(Chongqing Institute for Food and Drug Control,Key Laboratory of Condiment Supervision Technology for State Market Regulation,Chongqing 401120,China)
出处
《现代食品》
2022年第9期137-144,共8页
Modern Food
关键词
不确定度
原子荧光光谱法
总汞
大米
uncertainty
atomic fluorescence spectrometry
total mercury
rice
