溶液阴极辉光放电-原子发射光谱法是近年来兴起的一种新型水体金属离子检测技术, 它具有快速, 在线和低成本检测的显著特点。 以工业注射泵实现溶液阴极辉光放电激发源的流动注射进样, 再以窄带滤光片分别提取Na, K, Ca, Li, Sr和Cs金属元素发射光谱信号, 最后由光电倍增管和皮安表接收光谱信息光谱信号, 实现了水质金属元素的检测。 实验分析了注射容量分别为100和166 μL对1 mg·L-1的Na元素产生的信号强度的影响, 研究发现其信号强度的相对标准偏差(RSD)分别为4.64%和1.95%, 说明两种注射量稳定性都较好。 为了获得更好的分析性能, 实验分析了直流放电电压, 狭缝的宽度以及光电倍增管供压等参数对信号强度的影响。 实验结果表明, 在直流放电电压为1 000 V, 狭缝宽度为70 μm和光电倍增管供压为-800 V时获得了较高的信背比。 采用此装置在流动注射模式下, 测得了Na, K, Ca, Li, Sr和Cs六种金属元素检出限, 分别为2.78, 4.23, 589, 9.45, 981和83.6 μg·L-1。 实验最后对混合溶液标定物质中的Na和K元素进行了定量分析测量, 测量的误差分别为7.5%和6.67%, 精密度分别为1.24%和0.89%, 研究结果表明基于滤光片提取光谱的流动注射分析-溶液阴极辉光放电-原子发射光谱方法具有较高的检测准确度。

针对水体中污染较重且含量较高的可溶态痕量重金属镉 (Cd2+)、铜(Cu2+)、锌(Zn2+)、镍(Ni2+), 提出采用流动注射分光光度法测定海水中痕量可溶性重金属。首先分析了四种重金属离子 Cd2+、Cu2+、Zn2+、Ni2+在不同波长下的吸光光谱, 然后建立了 4水平 4因素的正交校正集作为多元线性回归数据分析模型, 最后搭建了重金属离子浓度测量装置, 检测了海水中的可溶性 Cd2+、Cu2+、Zn2+、Ni2+浓度, 检测下限可达 10-9(ppb)。

The spice model for photo catalytic sensor (PCS) proposed by Whig and Ahmad overcomes several drawbacks like complex designing, non-linearity, and long computation time generally found in the flow injection analysis (FIA) technique by Yoon-Chang Kim et al. for the determination of chemical oxygen demand (COD). The FIA technique involves the complete analysis including sampling and washing. The flow injection analysis is an analytical method for the measurement of the chemical oxygen demand by using the photochemical column. This method uses a bulky setup and takes 10 minutes to 15 minutes to get the output result which is a tedious and time consuming job. If the conventional method is continuously used for a long time then it is stable only for 15 days. The purpose of this paper is to propose a new floating gate photo catalytic sensor (FGPCS) approach which has low power consumption and more user-friendly, and it is fast in operation by the modeling and optimization of sensor used for water quality monitoring. The proposed model operates under sub-threshold conditions which are appreciated in large integrated system design. The results of simulation are found to be fairly in agreement with the theoretical predictions. The results exhibit near linear variations of parameters of interest with appreciably reduced response time.

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50.0～1 000.0 μgN·L-3(r≥0.999), 检出限为7.6 μgN·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。