氢化物原子荧光法测定饮料中总砷含量的不确定度评定

Evaluation of the Uncertainty of the Determination of Total Aresenic in Beverage Using Hydride Atomic Fluorescence Spectrometry

采用现代统计学方法对氢化物原子荧光光度法测定饮料中总砷含量的不确定度进行评估。通过建立数学模型,分析整个过程的不确定度来源,推导计算、合成扩展不确定度。结果表明,当饮料中总砷含量在定量限附近时,扩展不确定度为0.00082mg/L(k=2)。可如实反映测量的置信度和准确性,在实际的工作中具有较强的实用价值。

The uncertainty of determination of total arsenic in beverage using hydride atomic fluorescence spectrometry is evaluated though modem statistical methods. The main steps include establishing mathematical model, analyzing sources of uncertainty of the whole process, deducing and calculating, and compositing the expanded uncertainty. The results showed that the expanded uncertainty is 0.00082mg/L （k=2） when the total arsenic volume is within quantity limit. To accurately reflect the confidence and accuracy has practical value in actual work.