离子色谱法测定生活饮用水中4种阴离子含量的不确定度评定

目的评定离子色谱法测定生活饮用水中F~-、Cl~-、NO_3~-、SO_4~(2-)4种阴离子含量的不确定度,提高实验结果准确性。方法依据JJF 1059.1-2012《测量不确定度评定与表示》分析实验过程中引入的不确定度来源,计算各不确定度分量,最终合成扩展不确定度。结果在95%的置信区间下,样品检测结果:F~-含量为(0.034±0.002) mg/L, Cl~-含量为(0.617±0.027) mg/L, NO_3~-含量为(0.345±0.076) mg/L, SO_4~(2-)含量为(2.387±0.049) mg/L(k=2)。结论在实验过程中,不确定度主要来自标准曲线的拟合,其次是制备标准溶液和测量的重复性。

Uncertainty evaluation of determination of 4 anions in drinking water by ion chromatography

Objective To evaluate the uncertainty of the determination of F-, Cl?, NO3?, SO42? in drinking water by ion chromatography, and to improve the accuracy of experimental results. Methods According to JJF 1059.1-2012 Assessment and expression of measurement uncertainty, the sources of uncertainty introduced during the experiment were analyzed, and the various uncertainty components were calculated, and finally the extended uncertainty was synthesized. Results Under the 95% confidence interval, the sample detection results were as follows: the content of F?, Cl-, NO3? and SO42? was (0.034±0.002), (0.617±0.027), (0.345±0.076) and (2.387±0.049) mg/L (k=2), respectively. Conclusion In the experimental process, the uncertainty mainly comes from the fitting of the standard curve, followed by the preparation of the standard solution and the repeatability of the measurement.