【作者】 黄志英；

【导师】 杨明敏；

【作者基本信息】 南京农业大学 ， 农药学， 2003， 硕士

【摘要】 本论文有以下两部分内容： 第一部分：农药的电化学分析 对吡虫啉在玻碳电极上的电化学行为及其测定进行了研究。在0.2 mol·L^-1的NH₃-NH₄Cl（pH9.0）底液中，用方波伏安法检测，吡虫啉于-1.24 V（vs. Ag／AgCl）处产生一灵敏的还原峰，该还原峰的峰电流与吡虫啉的浓度在6.72×10^-6～1.68×10^-4mol·L^-1内成良好的线性关系。对1.50×10^-4mol．L^-1的吡虫啉溶液进行6次平行实验，相对标准偏差为2.7％。实验结果表明，吡虫啉在玻碳电极上有吸附性质。 用单扫描极谱方法研究了福美双-Cu²⁺配合物的伏安行为。在pH 4.0 HAc-NaAc缓冲液中，福美双与Cu²⁺形成配合物并于-1.06 V（vs. SCE）处产生一灵敏的极谱还原峰，其峰高与福美双的浓度在1.25×10^-6～3.00×10^-5mol·L^-1范围内呈线性关系。应用本方法测定植物样品中福美双的残留量并与HPLC法比较，结果满意。同时还结合分光光度法研究了Cu²⁺对福美双的降解行为，并探讨了该极谱波的电极过程机理。 第二部分：农药的残留分析 采用气相色谱法毛细管色谱柱分离、电子捕获检测器检测土壤中残留的六六六和滴滴涕含量。研究了索氏提取、振荡提取和超声波提取3种方法提取土壤中六六六、滴滴涕农药的效果，结果表明，振荡提取、超声波提取与索氏提取效果相当。当取样量为10g，方法检测限α-BCH、γ-BCH、β-BCH、δ-BCH、p p′-DDE、o p′-DDT、p p′-DDD和p p′-DDT分别为0.0001、0.0001、0.0003、0.0001、0.0002、0.0002、0.0001、0.0003 mg·kg^-1。加标回收率在67％～90％之间，相对标准偏差为0.7％～9.5％。方法准确、灵敏。 气相色谱法测定有机磷农药残留已被广泛应用。采用二氯甲烷振荡法提取蔬菜样品，HP-5弹性石英毛细管柱分离样品，气相色谱-硫磷检测器（GC-FPD）检测5种有机磷农药的残留量。方法简单，快速，灵敏，回收率在65％～92％。甲胺磷、氧化乐果、甲拌磷、乐果和对硫磷5种有机磷农药的最低检测浓度分别为0.005、0.003、0.003、0.002、0.002 mg·kg^-1。更多还原

【Abstract】 Two parts are give in the thesis:1. Electrochemical analysis of pesticideThe voltammetric behavior of imidacloprid at a glassy carbon electrode was investigated by square wave voltammetry. In a base solution of 0.2 mol L-1NH3-NH4C1 (pH 9.0) , square wave voltammetry displayed a sensitive reduction peak at -1.24 (vs. Ag/AgCl) . There was a good linear relationship between the peak current and the concentration of imidacloprid from 6.72 10-6 to1.68 10-4 mol L-1, the relative standard deviation of 1.50 10-4 mol L-1 imidacloprid in parallel assays was 2.7%. Imidacloprid also showed adsorptive characteristics at the electrode.The voltammetric behavior of Thiram-Cu (II) complex was studied by single-sweep oscillopolarogaphy. In a medium of HAc-NaAc (pH4.0) buffer solution, a sensitive reduction wave of Thiram-Cu (II) was obtained at -1.06 V (vs. SCE) . The peak current is proportional to the concentration of thiram over the range of 1.25 10~6~3.00 10-5mol L-1. The method has been applied to the determination of residues of thiram in plant and compared with HPLC with satisfactory results. And the degradation of thiram by Cu2+ was also studied by spectrophotometry. Furthermore, its electrode reaction mechanism was proposed in this paper.2. Analysis of pesticide residueThe Capillary gas chromatographic method (GC) was introduced for determining BHC and DDT residues in soil. And three extracted methods, such as Soxhelt Extraction, Mechanical Shaking Extraction (MSB ) and Ultrasonic wave Assistant Extraction (UAE) have been studied. The analytical results showed that the efficiency of USE, MAE was equivalent to that of Soxhelt. For sample of 10 g weight, the detection limit of -BCH, -BCH, - BCH, - BCH, p p’ -DDE, o p ’ -DDT, p p ’ -ODD and p p ’ -DDT were 0.0001, 0.0001, 0.0003, 0.0001, 0.0002, 0.0002, 0.0001, 0.0003mg kg-1 respectively.The sample recovery was 67%~ 90 %, and the relative standard deviation was 0.70%-9.5%.Gas chromatography method is widely used to determine the residues of the Organophosphorous pesticides. The organophosphorous pesticides were extracted from vegetable with dichloromethane, separated by capillary column and detected by GC-FPD. The method was proved to be simple, rapid and sensitive. Sample recovery was 50%~ 92 %, and the qautitatve limit of methamidophos, omethoate, phorate, dimethoate and parathion were 0.005 , 0.003, 0.003, 0.002 , 0.002 mg kg-1 respectively.更多还原