离子色谱法测定茶叶中氟化物、溴化物的不确定度分析

Uncertainty analysis of determination of fluoride and bromide in tea by ion chromatography

摘要: 对离子色谱法测定茶叶中氟化物、溴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。茶叶中氟化物和溴化物的相对扩展不确定度分别为4.104%、3.872%。结果表明,在影响检测结果的6个不确定度分量中,拟合曲线求溶液中目标离子引入的不确定度、标准溶液配制引入的不确定度、样品重复测定引入的不确定度是对结果影响较大的三个不确定度分量。可通过减少这些不确定度分量提高测量结果的质量。

Abstract: The uncertainty of fluoride and bromide in tea determined by ion chromatography was assessed.By analyzing calculation formula with uncertainty theories, the sources of uncertainty of determination were traced and quantitated.Related expanded uncertainty of fluoride and bromide in tea were 4.104% and 3.872% respectively.As the results showed, among 6 factors of uncertainty, the main factors coming from contents of targeted ions from linear fitting, standard solutions preparation and repeatedly determination influenced the results mostly.Through reducing the amounts of these factors, the quality of the determination results could be increased.