火焰原子吸收分光光度法测定地下水中钠的不确定度评定

Evaluation of Uncertainty in Determination of Sodium in Groundwater by Flame Atomic Absorption Spectrophotometry

本文采用火焰原子吸收分光光度法测定地下水中钠的含量,对测定中的不确定度来源进行分析和评估。同时,依据相关标准对标准溶液配制、贮备液稀释成使用液、校准曲线、样品测量重复性引入的不确定度进行分析。结果表明:本次选取的地下水水样钠含量为67.88 mg/L,扩展不确定度为5.52 mg/L,k=2。影响其测量不确定度的主要因素为校准曲线引入的不确定度和样品重复测量引入的不确定度。

In this paper,flame atomic absorption spectrophotometry was used to determine the content of sodium in groundwater,and the sources of uncertainty in the determination were analyzed and evaluated.At the same time,according to the relevant standards,the uncertainty introduced by standard solution preparation,stock solution dilution into use solution,calibration curve,and sample measurement repeatability was analyzed.The results show that the sodium content of the groundwater sample selected this time is 67.88 mg/L,the expanded uncertainty is 5.52 mg/L,and k=2.The main factors affecting its measurement uncertainty are the uncertainty introduced by the calibration curve and the uncertainty introduced by the repeated measurement of the sample.