原子荧光光度法测定牛乳中铅质量分数不确定度的评估

利用微波消解快速处理样品,并建立了原子荧光光度法测定牛乳中重金属铅质量分数的不确定度的评定方法。根据JJF1059-1999《测量不确定度评定与表示》技术规范的要求,分析并确定了该检测方法中各不确定度分量,评定牛乳中铅质量分数测定不确定度的主要来源为标准曲线的拟合和样品消解的回收率。通过对各变量的分析,计算各变量的不确定度,最后计算出的合成不确定度为0.0022 mg/kg,扩展不确定度为0.0044 mg/kg。

Uncertainty evaluation in measurement of Plumbum content in Cow milk by atomic fluorescence spectrometry

The samples were rapid processing by microwave digestion and a assess method of measuring uncertainty in lead levels of heavy metals for cow milk by atomic fluorescence spectrometry was established.According to the requirements in "Evaluation and Expression of Uncertainty in Measurement",the component of uncertainty was determined.The result show that the most important component of uncertainty in this method were the fitting of standard curve and the recovery of sample in dispelling.Through the analysis and consideration of each variable,the combined uncertainty was calculated as 0.0022 mg/kg,expanded uncertainty 0.0044 mg/kg.