离子色谱仪检定及整机性能不确定度评定

介绍电导检测器离子色谱检定方法。采用氯离子标准物质,使用泵流量设定值误差、流量稳定性、基线噪声、基线漂移、最小检测浓度、线性相关性、整机性能定性定量重复性等参数对离子色谱仪进行检定。同时用5 μg/mL氯离子为检测离子,结合JJF 1059.1–2012 《测量不确定度评定与表示》对整机性能不确定度来源进行考察。结果表明:在置信区间为95%时(包含因子k=2),氯离子的质量浓度为(4.94±0.35)μg/mL。经不确定度分析,标准工作曲线拟合引入的不确定度最大,其次是样品的重复随机测试过程。

Verification of ion chromatograph and evaluation of uncertainty of overall performance

The verification method of ion chromatograph was introduced.Chloride ion was used as the standard material,the pump flow setting error value,flow stability,baseline noise,baseline drift,minimum detection concentration,linear correlation,qualitative and quantitative repeatability of the whole machine were used for verification ion chromatograph.At the same time,5μg/mL chloride ion was used as the detection ion,according to JJF 1059.1–2012 Evaluation and Expression of Uncertainly in Measurement,the source of uncertainty of the overall performance in the measurement process was evaluated.The result showed that when the confidence interval was 95%(the contains factor k was 2),the standard quality control sample of chloride ion was(4.94±0.35)μg/mL.After uncertainty analysis,the uncertainty introduced by the standard working curve fitting was the largest,followed by the repeated random testing process of samples.