HG-AFS法测定地质样品中微量硒的不确定度评定

Uncertainty evaluation of determination selenium in geological samples by HG-AFS

通过氢化物发生-原子荧光光谱法(HG-AFS)对地质样品中的硒进行测定,对测定结果的不确定度来源进行分析,评定不确定度的分量。结果表明,该方法测量不确定度引入的最主要来源有两项:硒标准溶液配制过程和重复性测量样品。因此在实际分析过程中,应提高分析人员检测技能和规范操作,保证测定结果的准确性和可靠性。当测试样品中硒的含量为0.1631μg/g时,其扩展不确定度(k=2)为0.0081μg/g。

By determining the content of selenium in geological samples,the uncertainty sources of the measurement result were analyzed, and the uncertainty components were evaluated. The results showed that the uncertainty in measurement was contributed to the concentration calibration of Se standard solution and the repeatability of measurements. Therefore,analysts should improve analytical skills and standardizing operating procedures in the analyzing procedure to ensure the accuracy and reliability of the measured results. When the selenium content was 0.163 1 μg/g in test sample,the expanded uncertainty reached 0.008 1 μg/g(k=2).