改良离子选择电极法测定水样中硝酸盐氮

建立一种快速、简便的改良离子选择电极法用于水样中硝酸盐氮的测定。利用带有统计功能的计算器对离子选择电极法测定数据进行处理,可以直接得到水样中硝酸盐氮浓度,不需要建立标准曲线。方法的线性范围为0.15~50 mg/L,相关系数r=0.999 5,检出限0.045 mg/L,相对标准偏差分别为0.084%和0.114%,平均回收率102%。用于实际水样中痕量硝酸盐氮的测定,与国标法麝香草酚分光光度法比较,结果满意。

Improvement of measuring nitrate nitrogen method in water sample by ion selective electrodes

A improvement ion selective electrodes method for determination of nitrate nitrogen in water samples was set up.A statistics calculator for data handling which obtained in ion selective electrodes method can calculate the concentration of nitrate nitrogen.This method did not need standard curve because of the statistical treating process.The linear range was 0.15~50 mg/L with a correlation coefficient of 0.999 5 and the detection limit for nitrate nitrogen was 0.045 mg/L.The relative standard deviations were 0.084%,0.114%,respectively,and the average recovery was 102%(n=5).The improvement method is used to detect nitrate nitrogen in water and the results are satisfactory in comparison with those obtained by the method of thymol absorption spectrometry.