氟试剂分光光度法测定生活饮用水中氟化物的不确定度评定

目的建立氟试剂分光光度法测定生活饮用水中氟化物的的不确定度评定方法,从而找出测定过程中的关键环节及主要影响因素,为有效地提高检测工作的质量提供依据。方法建立数学模型,应用测量不确定度评定方法[1],分析测定过程中不确定度的来源,计算各不确定分量,合成和扩展不确定度。结果不确定度的主要来源为工作曲线拟合引入的不确定度、标准溶液配制过程引入的不确定度以及样品重复测定引入的不确定度。生活饮用水中氟化物浓度测定值为1.03 mg/L,计算其扩展不确定度为0.018 mg/L。结论控制测定过程中的关键环节及主要影响因素,可有效降低测定过程中引入的测量不确定度,从而保证了测定结果的准确可靠。

Evaluation of Uncertainty for the Determination of Fluoride in Drinking Water by Fluorine Reagent Spectrophotometric Method

Objective To establish a method for the evaluation of uncertainty to the fluoride detection in drinking water, so as to find out the key hnks and the main influence in the process of determination and to provide the basis for the ef- fectively improve the quality of the detection work.Methods To establish a mathematical model,and then to use the method about the evaluation of uncertainty to analyze the sources of the uncertainty of in the determination process, to calculate each component of the uncertainty in the determination process,finally to combine and expand the uncertainty. Results The major sources of uncertainty were identified as the standard regression carve,standard stock solution diluted and the sample repeated measurement.When the concentration of fluoride detection in drinking water was 1.03 mg/L,the expanded uncertainty calculated was 0.018 mg/L.Conclusion The key links and the main influence in the process of determination can help us to effectively reduce the measurement uncertainty, and to ensure the accuracy and reliability of measurement results.