钼粉中镍量测定的不确定度评定

Evaluation on Uncertainty of Nickel Content Measurement in Molybdenum Power

采用原子发射光谱法对钼粉中镍量进行了测定,并对其测量结果的不确定度进行了评定。确立被测量和测量方法,识别了各不确定度来源,并着重对测量结果重复性、样品和载体称量、工作曲线拟合过程、被测样品和标准样品中基体含量(文中含量均为质量分数)不一致等引入的不确定度分量进行了分析、计算和评定,合成标准不确定度,计算出扩展不确定度,报告测量结果不确定度。评定结果表明,标准工作曲线拟合过程引入的不确定度对总不确定度有较大的贡献率。

The nickel content in molybdenum power was determined by atomic emission spectrometry.The uncertainty of the measurement was evaluated.The measurand and method of the measurement were confirmed.The source of the uncertainty was identified.The uncertainty components,introduced by the repeatability of measurement,weighting of sample and carrier,fitting of standard calibration curve and inconsistency of the matrix content in the measured sample and standard sample,were analyzed,calculated and evaluated.The combined standard uncertainty and expanded uncertainty were calculated.The uncertainty of the measurement was recorded.The result of evaluation indicates that the sub-uncertainty introduced by the fitting of standard calibration curve is a key factor in affecting the total uncertainty.