氢化物发生-原子荧光法测定液态奶中总砷含量的不确定度评定

本文对氢化物发生-原子荧光法测定液态奶中总砷含量的不确定度进行了评定。分析了方法中不确定度的来源,测量结果的不确定度由样品制备、重复测量、标准物质、回归工作曲线等所引入的不确定度分量组成。在对各不确定度分量进行量化的基础上,通过合成得到测量结果的标准不确定度,在95%的置信概率下得到其扩展不确定度为0.0051mg/L。评定结果表明,校准曲线的线性回归和测量的重复性是影响该方法不确定度的主要因素。

Uncertainty Evaluation of Measurement Results for the Determination of Total Arsenic in Milk by Hydride Generation-Atomic Fluorescence Spectrometry

In this paper the measurement uncertainty for the deternfination of total Arsenic in milk by Hydride Generation-Atomic Fluorescence Spectrometry is evaluated. The sources of uncertainty were analyzed. They included sample preparation, repeated measurements, refences malerials used, regression working-curves, etc. Based on the quantitative analysis of each source, the extended uncertainty of measurement resuhs which was obtained from standard uncertainly （synthesis of uncertainties from each source） was 0.0051 mg/L. The evaluation indicated that the major sources of uneentainty were the hnearity of standard curve and the reproducibihty of the determination.