离子选择电极法测定饮用水中氟化物不确定度

Uncertainty Analysis of Determination of Fluoride in Drinking Water by Ion Selective Electrode Method

对离子选择电极法测定生活饮用水中氟化物含量进行不确定度分析评价。应用不确定度理论分析检测数学模型,对测定不确定度的来源进行分析和量化。3次平行测定生活饮用水中氟化物含量为0.505 mg/L,其扩展不确定度为0.015 mg/L,k=2。标准系列配制过程对不确定度的影响较大,是测量不确定度的主要影响因素。

The uncertainty of fluoride in drinking water determined by ion selective electrode method was assessed. By analyzing calculation formula with uncertainty theories, the sources of determination uncertainty were traced and quan- titatively analyzed. The average concentration of fluoride in drinking water was 0. 505 mg/L with 3 times of duplicate sur- vey, and its expanded uncertainty was 0. 015 mg/L（k =2）. The most primary influencing factors to uncertainty was the preparation of standard series in the measurement of uncertainty.