薄层流动固定电位时安法研究

薄层流动固定电位时安法,系在薄的小体积电解池中,用金盘作工作阴极,银-氯化银作阳极,控制于极谱极限电流电位,测定试样溶液由流动状态转换至静止状态时的时安电量。叙述了定量分析原理,电量-浓度方程式,实验方法,克服了电容电流及电极性能不稳定等干扰。灵敏度提高至10^-7M,噪音低,分辨力高,稳定,再现性好。与阳极解析伏安法相结合,优点显著。

STUDIES ON THE CONSTANT-POTENTIAL CHRONOAMPEROMETRY IN THE CASE OF LAMINA FLOW

The chronoamperometry at constant-potential under the condition of lamina flow has been suggested. The method is to measure the electrolytic current and time of the solution when its state changes from flow to stagnation and to calculate the coulomb. The electrolytic potential is controlled at the position of the polarographic limiting-current. The electrolytic cell is made small and thin in size and contains three electrodes: a Ag/AgCl for reference electrode,a gold ring for auxiliary electrode and a gold dish for indicator electrode.An equation that relates coulombs and concentrations of the solution has been given. The principle of quantitative analysis and experimental operations has also been described in the present paper. After the interference caused by capacity currect and unstability of the electrode were eliminated, the sensitivity of the method increased to the extent of 10^-7M. It has been proved experimentally that this method has several advantages, such as low noise, high resoluting power, stableness and good repro-ducibility. The advantages of stripping analysis were also shown obviouslywhen combined with chronoamperometry.