夹管电磁阀定量-流动注射分光光度法测定海水中总溶解氮

采用三个夹管电磁阀联用代替传统六通阀的样品定量方法,自制一套多通道流动注射分光光度分析仪,并优化仪器的最佳测试条件,实现了海水中总溶解氮含量的测定。本分析系统结构简单,操作方便,测定频率为27个.h-1。测试结果表明,总溶解氮的线性范围分别为50.0～1 000.0μgN.L-3(r≥0.999),检出限为7.6μgN.L-3。加标回收率为87.3～107.2%,RSD为1.35～6.32%(n=6)。经t检验分析,本方法与国标方法测定数据不存在显著性差异,可适用于海水中总溶解氮快速测定分析。

Flow injection-spectrophotometric determination of total dissolved nitrogen in seawater based on quantificational solenoid valves

Using three pipe clamp solenoid valves to replace the traditional six-port valve for sample quota, a set of multi-channel flow injection analyzer was designed in the present paper. The authors optimized optimum instrumental testing condition, and realized determination and analysis of total dissolved nitrogen in seawaters. The construction of apparatus is simple and it has the potential to be used for analysis of total dissolved nitrogen. The sample throughput of total dissolved nitrogen was 27 samples per hour. The linear range of total dissolved nitrogen was 50.0-1 000.0 microgN x L(-3) (r > or = 0.999). The detection limit was 7.6 microgN x L(-3). The recovery of total dissolved nitrogen was 87.3%-107.2%. The relative standard deviation for total dissolved nitrogen was 1.35%-6.32% (n = 6). After the t-test analysis, it does not have the significance difference between this method and national standard method. It is suitable for fast analysis of total dissolved nitrogen in seawater.