HG-AFS法测定土壤样中硒的不确定度评定

Uncertainty Evaluation of Determination of Selenium in Soil by HG-AFS

[目的]对测量土壤样品中硒的不确定度进行评定。[方法]采用氢化物发生-原子荧光光谱法(HG-AFS)对土壤样品中的硒进行测定,根据《测量不确定度评定与表示》对其不确定度进行分析。[结果]测量不确定度主要来源于标准溶液配制、曲线拟合、样品制备、重复测量,并且得出标准不确定度和扩展不确定度。[结论]当土壤中硒的含量为0.642 mg/kg时,其扩展不确定度为0.036 mg/kg(k=2)。

[Objective] The uncertainty of the measurement of selenium in soil was evaluated.[Method] Selenium in soil samples were measured by using hydride generation atomic fluorescence spectrometry（HG-AFS）.The uncertainty was analyzed according to Evaluation and Expression of Uncertainty in Measurement.[Result] The impacts of major source of measurement uncertainty were preparation of standard solution,curve fitting,samples preparation and measurement repeatability,and the standard and expanded uncertainty were gained.[Conclusion] When the selenium content was 0.642 mg/kg in soil,the expanded uncertainty reached 0.036 mg/kg（k=2）.