石墨炉原子吸收法测定空心胶囊中铬含量的不确定度分析

Uncertainty Analysis of Chromium Content in Hollow Capsule Determined by Graphite Furnace Atomic Absorption Spectrometry

通过石墨炉原子吸收法测定胶囊中的铬含量,建立数学模型,分析评定不确定度的来源和影响程度,实验中样品称量、微波消解、回归曲线和重复性测试对合成相对不确定度的贡献比较大,计算合成标准不确定度为0.045 mg/kg,扩展不确定度为0.11 mg/kg。

The chromium content in the hollow capsule was determined by the graphite furnace atomic absorption spectrometry. The mathematic model was established. The sources of uncertainty and the influence degree were analyzed and assessed. The sample weighing, microwave digestion, regvession curve and repeatability test are mostly contributed to the combined relative uncertainty. The calculated combined standard uncertainty is 0.045 mg/kg, the expanded uncertainty is 0.11 mg/kg.