乙草胺的气相色谱分析

对酰胺类除草剂乙草胺在土壤和玉米中残留及其在土壤中降解动态的研究结果表明．本方法用丙酮提取样品后，蒸发至干，用５０％乙酸－石油醚定容，过弗罗里硅土柱，用２５ｍＬ５０％乙醚－石油醚淋洗，蒸发至干，用甲苯定容，用ＧＣ－ＥＣＤ进行定量．添加浓度在０．０５～５．０ｍｇ／Ｌ时，平均回收率在９４％，变异系数小于８％．本方法具有简便、快速、分析成本低、低毒等优点，乙草胺在土壤中的半衰期为：ｔ＿（１／２）＝１５．５８～１６．５０ｄ．

GAS CHROMATOGRAPHIC DETERMINATION OF ACETOCHLOR WITH ECD DETECTOR

The method of determination of a cetochlor in soil and corn by gas chromatography was established.The sample was extracted with acetone.The extracts was evaporated to dryness. Residues were redissolved by 50% cther-petroteum 20mL.It was cleaned-UP by colume packed with Florisil, and eluted with ether-petroleum(50%)25ml.evaporatd to dryness,and the residues was redissolved with 5mL toluene in sample preparation for gas chromatography.At 0.05-5.0mgL-1 fortificating level.The mean recovery of 94% was achieved with standard deviation<8.0%. This a simple rapid. low cost and low toxic methos.The t1/2for degradation of acetochlor in soil is 15.58～16.50days.