The application of soxhlet, ultrasonic and accelerated solvent extractiontechniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT,p,p'-DDT and p,p'-DDE) in Taihu Lake ...The application of soxhlet, ultrasonic and accelerated solvent extractiontechniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT,p,p'-DDT and p,p'-DDE) in Taihu Lake sediment samples is described. It was found that the limits ofquantification ranged from 0.002 μg g^(-1) to 0.004 μg g^(-1), and the recoveries oforganochlorine pesticides with the three extraction techniques were acceptable ( 】80.7%). With amass selective detector, better results were obtained by accelerated solvent extraction usinghexane-acetone (1:1) as compared with soxhlet and ultrasonic extraction. It was shown that theaccelerated solvent extraction was the optimum technique for the analysis of organochlorinepesticides in sediments. The general features of the three extraction techniques are also presented.展开更多
文摘The application of soxhlet, ultrasonic and accelerated solvent extractiontechniques to the analysis of six organochlorine pesticides (α-HCH, β-HCH, γ-HCH, o, p'-DDT,p,p'-DDT and p,p'-DDE) in Taihu Lake sediment samples is described. It was found that the limits ofquantification ranged from 0.002 μg g^(-1) to 0.004 μg g^(-1), and the recoveries oforganochlorine pesticides with the three extraction techniques were acceptable ( 】80.7%). With amass selective detector, better results were obtained by accelerated solvent extraction usinghexane-acetone (1:1) as compared with soxhlet and ultrasonic extraction. It was shown that theaccelerated solvent extraction was the optimum technique for the analysis of organochlorinepesticides in sediments. The general features of the three extraction techniques are also presented.
文摘提出了加速溶剂萃取联合凝胶色谱净化-气相色谱-质谱法同时测定土壤中21种酚类化合物含量的方法。取研细过筛后的土壤样品(含水率15%~20%)10 g,加入6 g硅藻土混匀并研磨,置于萃取罐中,以体积比2∶1的二氯甲烷-正己烷混合溶液于120℃进行加速溶剂萃取,萃取液经无水硫酸钠脱水,再用二氯甲烷充分淋洗无水硫酸钠,合并全部有机相,浓缩至1 m L,通过凝胶色谱进行净化,收集9~18 min的流出液,浓缩至1 m L,在HP-5MS色谱柱上按照柱升温程序分离,质谱分析采用全扫描(SCAN)模式。结果表明,21种酚类化合物的质量浓度在2.50~50.0 mg·L^(-1)内与对应的峰面积呈线性关系,检出限(3.143s)为0.02~0.07 mg·kg^(-1)。按照标准加入法进行回收试验,回收率为73.4%~107%,测定值的相对标准偏差(n=6)均不大于17%。方法用于2份土壤样品分析,21种酚类化合物均未检出。方法用于土壤质控样品分析,21种酚类化合物的测定值均在认定值的不确定度范围内。