计算机控制的电位溶出分析法的研究

电位溶出分析是近年发展起来的一种新的电分析化学技术。在电位溶出分析中,痕量金属首先电解富集在汞膜电极中然后通过溶液中氧化剂氧化溶出,并记录溶出过程的电位-时间曲线,这种方法操作简便,灵敏度高,元素之间干扰小。本文介绍了利用微型计算机控制的电位溶出分析系统,讨论了仪器的硬件结构和软件设计,利用微机实现了恒电位,自动存取分析方法和数据,分析过程自动控制,自动扣除电容本底和数据平滑,采用静止拟微分电位溶出方式使其灵敏度大大提高。富集五分钟最低可检测0.08ng/ml镉。在1ng/ml的镉离子和1ng/ml铅离子浓度下,连续测定11次,其相对标准偏差分别为3.8%和4.9%。

Study on Microcomputer Controlled Potentiometric Stripping Analysis

A microcomputer controlled intelligent potentiometric stripping analysis system is described and its hardware and software are discussed in detail,with which trace metals are first amalgamated into a mercury film electrode and then oxidized back into solution by an oxidant.Using this system,whole process which includes the store and recall of analytical conditions and data,the control of potential,the data smoothing and elimination of background is carrying out automatically with little interference between other elements.The detection limit of Cd~(2+) is 0.08ng/ml by stationary pseudo- derivative potentiometric stripping with 5 min enrichment and the relative standard deviation are 3.8% and 4.9% for determination of 1 ng/ml Cd~(2+) and Pb~(2+) respectively.