论文部分内容阅读
本文叙述了应用极谱、循环伏安法、库仑法和交流阻抗法等方法研究尼克酰胺在二甲基甲酰胺(DMF)溶液中、在汞膜和滴汞电极上的阴极还原机理:始由单电子电化学步骤形成菏负电的自由基,后自由基迅速二聚合。借助微型计算机用曲线拟合法求得18℃下二聚合速度常数为1.0×10~6升·摩尔~(-1)秒~(-1)。交流阻抗实验结果表明:尼克酰胺在汞膜电极上的吸附行为符合朗格谬尔吸附等温线,且吸附使尼克酰胺分子活化,更易于电子传递。
This paper describes the use of polarography, cyclic voltammetry, coulometry and AC impedance method for the study of nicotinamide in dimethylformamide (DMF) solution, mercury cathode and mercury drop in the cathode reduction mechanism: Single-electron electrochemical process to form negative charge of free radicals, free radicals quickly dimerized. The curve of the rate of dimerization at 18 ℃ was 1.0 × 10 ~ 6 L · mol ~ (-1) s ~ (-1) obtained by the curve fitting method of microcomputers. The results of AC impedance experiment show that the adsorption behavior of nicotinamide on mercury membrane electrode accords with Langmuir adsorption isotherm, and the adsorption activates nicotinamide molecule, which makes it easier to transfer electron.