ICP-AES法测定土壤中铬含量的不确定度评定

Evaluation of Uncertainty of Determination of Chromium Content in Soil by ICP-AES

根据等离子体原子发射光谱(ICP-AES)法测定土壤中铬的过程,建立相应的数学模型并对模型中各个参数进行了不确定度来源分析。结果表明,测定结果的不确定性主要来源于标准曲线的浓度与光谱强度拟合直线方程求铬含量的不确定度、标准溶液和配置标准工作溶液时的不确定度,其次为重复性不确定度;定容体积和样品称量过程的不确定度对测量结果的不确定度贡献相对较小。

According to the process of determination of Chromium in soil using plasma-atomic emission spectrum （ICP-AES）, a mathematic model was established and the uncertainty source of every model parameter was analyzed. The results showed that the uncertainties sourced mainly from the calculated Chromium content by regression equation of concentration versus specu＇, al intensity and preparation of standard liquid; secondly from the uncertainty of repeatability. The uncertainties from the determination processes for volume and weight contributed little to the overall uncertainty.