【摘要】 建立了杀菌剂醚菌酯在黄瓜和土壤中的残留分析方法,并研究了其在黄瓜和土壤中的消解动态和最终残留。样品经丙酮超声提取、二氯甲烷液-液分配和弗罗里硅土净化后,通过GC-NPD检测。该方法最小检出量为9×10-12g,在黄瓜和土壤中的最低检测浓度分别为0.005和0.010mg/kg,添加回收率为89.4%~104.3%,变异系数为4.6%~7.0%。残留动态试验结果表明,施药浓度为推荐剂量的两倍时(有效成分300g/hm2),醚菌酯在黄瓜和土壤中的半衰期分别为6.4和10.3d。在有效成分为150和300g/hm2的剂量条件下,施药3~4次,施药后第5d黄瓜中醚菌酯残留量低于欧盟规定的MRL值(0.05mg/kg)。更多还原

【Abstract】 The residue analysis method of kresoxim-methyl and its dissipation rate in cucumber and soil were studied.Kresoxim-methyl were extracted from cucumber and soil matrices with acetone,purified by liquid-liquid extraction and Florisil cartridges,and then determined by GC with NP-detector.The limit of detection was estimated to be 9×10~-12 g,and the minimum determination concentration of kresoxim-methyl in cucumber and soil was 0.005 mg/kg and 0.010 mg/kg,respectively.The average recoveries ranged from 89.4% to 104.3% with a coefficient variation between 4.6% and 7.0%.The results showed that the half-lives of kresoxim-methyl in cucumber and soil were 6.4 days and10.3 days,respectively,at double of the recommended dosage300 g/hm~2.The present studyrevealed that the cucumber was sprayed at 3~4 times successivvely at the recommended dosages150 g/hm~2 and double of that,the residues in cucumber were below the MRL0.05 mg/kg,fixed by EU after 5 days for both treatments.更多还原