总氮测定中空白吸光值的控制方法  

Method of Blank Absorbance Value Control in the Determination of Total Nitrogen

作　　者：叶玲[1] 胡明娟[1] 

机构地区：[1]泗阳县环境监测站,江苏泗阳223700

出　　处：《污染防治技术》2016年第4期70-72,共3页Pollution Control Technology

摘　　要：用紫外可见分光光度法测定水样中的总氮时,经常出现空白值偏高的情况,这将直接加大了分析测定的系统误差。为了保证总氮分析测定的精密度和准确度,以满足总氮测定技术要求,分析了实验用水、过硫酸钾和氢氧化钠的纯度、过硫酸钾存放时间和加入量、消解过程、玻璃器皿清洁程度、实验环境等对空白值的影响,找出空白值偏高的原因,提出减少空白值的对策。Using uvvis spectrophotometry determination of total nitrogen in water samples,often appears to be a higher blank absorbance value,which would directly increase the analysis system error of measurement. In order to guarantee the accuracy and precision of measuring total nitrogen to meet the requirements of total nitrogen determination,the influences of test water,the purity of potassium persulfate and sodium hydroxide,the storge time and dosage of potassium persulfate,the digestion process,glass cleaning degree and experiment environment on the blank value were analysed. The reasons of higher blank value were found out so that some countermeasures to reduce blank value were put forward.

关 键 词：总氮 空白值 影响因素 

分 类 号：X830[环境科学与工程—环境工程]