分光光度法测定地热矿水中偏硅酸含量的不确定度评定

Uncertainty evaluation of spectrophotometric determination of silicic acid in geothermal mineral water

文章对分光光度法测定地热矿水中偏硅酸含量进行不确定性评定,建立不确定度的数学模型,得出分光光度法测定地热矿水中偏硅酸含量的扩展不确定度,并测定广西贺州市西溪地热矿水中偏硅酸含量,同时测定了国家水中二氧化硅成分分析标准物质GBW(E)080236(标准值及扩展不确定度为:20.0±0.8mg/L,k=2),以验证方法的可靠性。结果表明,广西贺州市西溪地热矿水,其偏硅酸含量及扩展不确定度报告为125.3±13.0mg/L,k=2。对国家水中二氧化硅成分分析标准物质,本实验室测定结果为:20.3mg/L,与标准值相符合。

The method and uncertainty evaluation of spectrophotometric determination of silicic acid in geothermal mineral water were studied. The mathematic model of uncertainty of the method was established. The expanded uncertainty of the method was acquired. The content of silicic acid in Xixi geothermal mineral water in Hezhou City, Guangxi Province was determined. At the same time, in order to verify the reliability of the method, a national standard substance for the analysis of silica composition in water （GBW（E）080236 standard value and extension uncertainty： 20.0±0.8 mg/L, k=2） was determined. The results showed that the content and expansion uncertainty of silicic acid in Xixi geothermal mineral water in Hezhou City were 125.3±13.0mg/L, k=2. The determination result of the standard substance was 20.3 mg/L, which was consistent with the standard values.