通过ＭＮＤＯ计算及相关实验结果，用取代基非定域活性概念分析了羟基、氨基及硝基在—ＮＮ—上的电子效应，阐述了取代基影响偶氮键生物降解活性的电子结构机理，并提出将ＭＮＤＯ统计集居分析中的活性电荷ＱＡ（其值可反映原子在分子中的化学活性）作为关联偶氮键生物降解活性的电子结构参数 Based on MNDO calculations and related experimental results, the electronic effects of hydroxyl, amino and nitro groups on -NN- were analyzed by using the concept of substituent nondomain activity, and the electronic structure mechanism of the substituents affecting the biodegradability of azo bonds was described. It is proposed that the active charge QA (the value of which can reflect the chemical activity of an atom in a molecule) in the population analysis of MNDO statistics is used as the electronic structure parameter of the biodegradation activity of the azo bond