土壤浸提液中NO_2^-和NO_3^-的同时测定

Simultaneous Determination of Nitrate and Nitrite in Soil Extracts

利用二阶导数分光光度法,选择215.0和222.9nm两波长,用于土壤浸提液中NO_2^-和NO^-含量的同时测定。标准溶液的浓度范围在0～15μg/mL之间服从Beer定律。检测限NO_2^-为0.4μg/mL,NO_3^-为0.2μg/mL.标准混和物测定误差在-2.95％～+0.906％之间。土壤浸提液中添加标准液后测定,其回收率为NO_2^-99.79％～104.8％;NO_3^-103.0％～105.2％.对26种阴阳离子作了干扰试验,测定了西安污灌区土壤和水稻土中NO_2^-和NO_3^-含量。

The application of derivative ultraviolet spectrophotometry to the simultaneous determination of nitrate and nitrite is described . The second-derivative absorbances at 222.9 and 215. 0 nm are used for the respective of determinations of nitrate and nitrite. Beers Law was obeyed over a range of 0 to 15 ug/mL for total nitrate and nitrite. The determined error of standard mixtures of nitrate and nitrite was between -2.95% to +0.906%. After thes tandard was added to' the determination was done' whose recovery percentage was between 99.79 to 104.8% for nitrite and 103.0% to 105.2% for nitrate. Also, the interference tests were conducted for the negative and positive ions, and the amounts of nitrate and nitrite in soils of the irrigated area by sewage in Xian and paddy soils were determined.