| a-Cypermethrin ( α-CPM) was an active isomer of cypermethrin, it was a kind of low-toxic, high-effective and broad-spectrum pyrethroids. So it had a good potential of application in agriculture. But when it was used, some of them would enter into the waters such as rivers, lakes, etc. in any way or another, resulting in some environmental pollution and ecological destruction. Thus, it is important to understand the behavior and fate of α-CPM in the environment.Photolysis was one of the main degradation approaches of pesticides in environment. Photo-stability had a direct influence on the effectiveness and persistency of pesticides. In order to comprehensively evaluate environmental behavior and its fate, the photolysis and its influence factor of α-CPM in environment was studied, in the laboratory. The main conclusions obtained were listed as follows.Chapter one was introduction, in which the basic concepts, theories and current advances were reviewed briefly on photolysis. The contents and significances of this research were also included in this chapter.In the chapter two the photolysis of α-CPM in different solutions was studied under the irradiation of 300W high pressure mercury lamp (HPML). The results showed that the photolysis of α-CPM in pure water, methanol, ethanol, acetic acid, acetone, petroleum ether followed a pseudo-first-order kinetics. The photolysis rates of α-CPM in these solutions were arranged as the order of methanol> ethanol> acetone> petroleum ether> pure water>acetone.The photolysis of α-CPM under different lights and in different pH value buffer solutions, different kinds of water were studied in chapter three. The results showed that: (1) Between the two light sources(sun light, 300W HPML), the photolysis rate of α-CPM under mercury lamp was higher than sun light obviously. It was obvious that the photolysis rate of α-CPM under HPML was 195.02 times than that of under the sun light when the illumination intensity is at close range. (2)The photolysis rate...
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