紫外导数分光光度法直接测定饮用水中的硝酸根含量

Direct Determination of Nitrate in Drinking Water by Ultraviolet Second derivative Spectrophotometry

在酸性条件下，用二阶导数及零交技术，取２２３．５ｎｍ处的导数值可消除水中常见离子的干扰．该法的线性范围为０—１３０μｇ／５０ｍｌ，检出限为０．０８μｇ·ｍｌ－１，加标回收率在９５％—１０１％之间，适用于自来水。

In the presence of sulphuric acid,interferences such as NO - 2,HCO - 3,CO 2- 3 etc. can be eliminated by the Zero cross technique.Beer's law is obeyed in the range of 0—130μg/50ml,and the limit of detection is 0.08μg·ml -1 .The recovery is range of 95%—101%.The method was applied to the determination of nitrate content in the drinking water with satisfactory results.