新农药环境化学行为研究(Ⅶ)除草剂哌草丹(Dimepiperate)在土壤、水环境中的滞留、转化  

ENVIRONMENTAL BEHAVIOR OF PESTICIDE (Ⅶ) PERSISTENCE AND TRANSFORMATION OF HERBICIDE DIMEPIPERATE IN SOIL-WATER ENVIRONMENT

作　　者：刘维屏[1] 邵颖[1] 王琪全[1] 

机构地区：[1]浙江大学化学系

出　　处：《环境科学学报》1998年第3期290-295,共6页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金

摘　　要：研究了除草剂哌草丹在土壤、水环境中的吸附、脱附、水解及光解过程．结果指出：哌草丹在土壤上的吸附主要受土壤有机质的影响，粘土矿也有一定作用．吸附和脱附均可用Ｆｒｅｕｎｄｌｉｃｈ方程描述；根据降解产物推测了哌草丹的水解和光降解的机理，哌草丹的水解产物为２苯基丙烯和六氢吡啶等，六氢吡啶可与土壤粘土矿（蒙脱石）作用，并与蒙脱石层间阳离子形成配合物；哌草丹光降解的产物为六氢吡啶。Adsorption, desorption, hydrolysis and photolysis of demepiperate, S(α,α dimethybenxyl)—1piperidinecarbothioate, in three soils and aqueous solution were studied. The adsorption isotherms were conformed to be Frundlich type. The Kf values increased with increasing organic carbon content of the soils. The desorption isotherms were also conformed to be Freundlich type. The Kdes values were higher than those for adsorption and increased with increases in concentration of initially adsorbed dimepiperate. On Fe^(3+)clay, this interaction leads to hydrolysis of the thioester bond and the formation of the thiol and carbamic acid derivatives of the thioester bond, and the formation of the thiol and carbamic acid derivatives. A photolysis mechanism which accounts for the formation of the photoproducts was proposed.

关 键 词：哌草丹 水解 光解 农药 环境化学行为 除草剂 

分 类 号：X132[环境科学与工程—环境科学] X592.02