ICP-AES法测定水中硫酸根的不确定度

Analysis of Uncertainty for Determination of SO_4^(2-) in Water by ICP- AES

采用电感耦合等离子体发射光谱法(ICP-AES)测定水中硫酸根含量,依据不确定度评定的方法,分析了不确定度来源,量化不确定度分量,计算检测结果的合成标准不确定度和扩展不确定度。饮用水样品中硫酸根平均值为35.85 mg/L(n=6),扩展不确定度为0.56 mg/L。结果表明ICP-AES测定水中硫酸根的不确定度主要来源于标准溶液的配制、标准曲线拟合及实验过程的重复性测定。

To evaluate the uncertainty of determination of sulfate in water by inductively coupled plasma atomic emission spectrometry（ ICP- AES）. Each source of uncertainty,arising from the procedure of testing,was analyzed and confirmed,according to the guidelines of the uncertainty in measurement. After each uncertainty component was evaluated,the combined standard uncertainty and the expanded uncertainty of the result were calculated. The expanded uncertainty was 0. 56 mg / L when the concentration of sulfate radical in drinking water was 35. 85 mg / L.The measurement uncertainty of the concentration of sulfate radical comes primarily from the preparation of the standard series solution,the fitting of standard curve and the repeated measurements.