水质氨氮的分光光度法测定及不确定度评定

Uncertainty Evaluation for Determination of Ammonia Nitrogen in Water by Spectrophotometry

以水样中氨氮为研究对象,采用纳氏试剂分光光度法,通过测定重复性、标准溶液配制和标准曲线拟合等分量,对水样中的氨氮含量测定时影响分析结果的不确定度因素进行评定,结果表明,所测水样中氨氮含量为(13.2±0.26) mg/L,标准曲线拟合引起的不确定度为影响不确定度的主要因素。

The study adopts Nessler′s reagent spectrophotometric method to determinate the ammonia nitrogen content in water, and make evaluation of uncertainty through several factors such as measurement repeatability 、standard solution and calibration curve fitting that affect the determination result. The results show that the ammonia nitrogen content in water is(13.2±0.26) mg/L, calibration curve fitting is a major influence of uncertainty of determination of ammonia nitrogen..