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目前实验室中测定咔唑的方法,都缺乏特性,因此某些杂质也被当作咔唑测定了。用极谱法测定亦有类似的缺点。因咔唑的半波电位和其他(存在着的)物质的半波电位太相接近,以致不可能进行确实的测量。捷克科学家对极谱测定方法,作了改进。在极谱测定前,先将咔唑转化(在80℃时于醋酸中用亚硝酸钠处理之)为N-亚硝基咔唑,然后立即在吡啶的水溶液中进行测定。还原反应在广大的pH 值范围内于滴汞电极上以四个电子的转移按下式进行:
Currently, the method for the determination of carbazole in the laboratory is characterized by a lack of properties and therefore some of the impurities have also been evaluated as carbazole. Polarographic determination with a similar shortcomings. Since the half-wave potential of carbazole is too close to the half-wave potential of other (existing) substances, it is impossible to make a true measurement. Czech scientists improved the polarographic method. Carbazole conversion (treated with sodium nitrite in acetic acid at 80 [deg.] C.) was N-nitrosocarbazole prior to the polarographic determination and was immediately determined in aqueous pyridine. The reduction reaction is carried out on a drop mercury electrode with a shift of four electrons over a wide range of pH values according to the following equation: