液态肥料中氨基酸态氮两种测定方法比较

采用甲醛-指示剂滴定法、甲醛-电极法测定液态肥料中的氨基酸态氮。结果表明,两种方法均适合于液态肥料中氨基酸态氮的测定,其中甲醛-电极法重复性试验标准偏差为0.013 0,变异系数为1.320%,平均回收率为99.25%,回收率标准偏差为0.978 0,变异系数为0.985%,均小于甲醛-指示剂法的相应参数,表明甲醛-电极法检测精度高于甲醛-指示剂法。甲醛用量以10.0 mL为宜。

The Comparison of Two Determination Methods for Amino Acid Nitrogen in Liquid Fertilizer

Using formaldehyde Indicator method and formaldehyde electrode method determine Amino acid nitrogen in liquid fertilizer.The results show that both methods were suitable for liquid fertilizer in the determination of amino acid nitrogen,meanwhile,using formaldehyde electrode method,repeatability standard deviation was 0.013 0,coefficient of variation was 1.320%,the average recovery was 99.25%,standard deviation of recovery was 0.978 0,recovery coefficient of variation was 0.985%,these data were less than the corresponding parameters of using formaldehyde Indicator method,indicating,the detection accuracy of formaldehyde electrode method was higher than of formaldehyde Indicator method.Suitable amount of formaldehyde was 10.0 mL.