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第二次世界大战结束后,1947年以来,磷有机杀虫剂在农药中取得非常卓越的地位。它拥有四大优点,为前此任何杀虫剂所不能比拟的。第一是效能极高。旧的药剂在百分之几的浓度能杀死害虫,性能已属十分良好,而磷有机杀虫剂的有效浓度则为万分之几到百万分之几。所以从前每亩地杀虫需要几公斤到几十公斤的药,现在一公斤的药可用于几十亩、几百亩、甚至几千亩。第二是品种繁多。滴滴涕类型在杀虫剂中品种可算较多的,(?)代环戊二烯类型则更多一
Since the end of World War II, since 1947 phosphorus organic insecticides have made a very prominent position in pesticides. It has four major advantages that are unmatched by any pesticide. The first is extremely efficient. The old pesticides kill pests at a few percent of the concentration and the performance is already very good, while the effective concentration of phosphorus organic insecticides is a few percent to a few parts per million. Therefore, in the past, insecticide needed several kilograms per mu to tens of kilograms of medicine, and now one kilogram of medicine can be used for dozens of mu, several hundred mu or even several thousand mu. The second is a wide variety. DDT types in insecticides can be considered more varieties, (?) Substituted cyclopentadiene type is more one