农药丁吡吗啉与腐殖酸作用机理探讨

探讨农药丁吡吗啉与腐殖酸的作用机理， 可进一步了解农药在土壤中腐殖酸催化下降解的行为过程。将市售腐殖酸进行逐级分离，获得黄腐酸、棕腐酸和黑腐酸的固态或溶液状态，而后分别与农药丁吡吗啉进行作用，利用红外，荧光两种分析方法对其作用机理进行了解释。结果表明，三组分与丁吡吗啉之间广泛存在范德华力、次级键等弱作用力。黄腐酸与丁吡吗啉之间存在氢键和电荷转移吸附等作用力，棕腐酸与丁吡吗啉存在电荷转移吸附等作用力，黑腐酸与丁吡吗啉之间的作用力最弱，即依照黄腐酸、棕腐酸、黑腐酸三组分平均分子量依次递增的顺序，与农药丁吡吗啉之间的作用力依次降低。

The Functional Mechanism between the Pesticide Pyrimorph and Humic Acid

In the present experiment, we mainly discussed the function mechanism between the humic acid and a new kind of fungicide Pyrimorph，aiming to play a positive role in the reduction of contamination caused by pesticides on environment.After the disposition step by step, the humic acid was separated into three parts.Then IR and fluorescence analytical methods were employed to explain the functional mechanism between the pesticide and each part of humic acid.As a result, there are extensive interactions between the three parts of the humic acid and the fungicide Pyrimorph.The interactions between fulvic acid and Pyrimorph are mainly the H-bond and the transfer of the electric charge caused by the C=O of the Pyrimorph and the —OH of the fulvic acid, and the interaction between matomeilon and Pyrimorph is mainly the transfer of the electric charge, and the interaction between humin and Pyrimorph is the weakest.It was showed that the fulvic acid is the most active part in the humic acid.That’s to say the intensity of the interaction between the three parts of the humic acid and the fungicide Pyrimorph is smaller and smaller with the order of molecular weight from small to big, namely fulvic acid, matomeilon acid and humin.