氯氰菊酯在PMMA膜及茶叶表面光解动态的研究

Study on Photolysis Dynamics of Cypermethrin in Tea Leaf and PMMA Film

以PMMA膜为参照, 研究了农药氯氰菊酯在茶叶表面于人工光源和不同季节太阳光下的光分解动态。结果表明,氯氰菊酯在紫外光下容易分解,254nm光源下的半衰期仅为0.91小时;由于光敏剂的作用,茶叶上氯氰菊酯的光解速率远比PMMA膜上快;春、夏、秋各季茶叶上的光解速率常数分别为0.00786h-1、0.00888h-1和0.00549h-1。

The photolysis dynamics of Cypermethrin in tea leaf under artificial light and sunshine was in vestigated with special reference to that in PMMA film.It indicated that Cypermethrin degra-dated rapidly under 254nm light ( UV ) , the half life time was only 0.91 hours.May be for the effect of photosensitizer, the photolysis rate of Cypermethrin in tea leaf was larger than that in PMMA film. The photolysis rate constant of cypermothrin in tea leaf under spring, summer,and autumn conditions was 0.00786h^(-1), 0.00888h^(-1), and 0.00549h^(-1) respectively.