The mechanisms of hydrolysis, microbialdegradation and photodegradation are base-catalyzed nucleophilic substitution reaction, enzyme-catalyzed hydrolysis, free-radical reaction respectively.

• 指出：灭幼脲类杀虫剂的水解、微生物降解和光解机理分别为碱催化的亲核取代反应、酶催化的水解反应及自由基反应。