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微波萃取-双ECD气相色谱法测定土壤中的多氯联苯 总被引:2,自引:0,他引:2
建立了利用微波萃取和双ECD联用技术,对土壤中多氯联苯(PCB)的分析方法,通过对回收率、重现性及精密度的测定,其结果均优于传统索氏萃取方法。利用微波萃取可快速、准确、有效地测定土壤中PCB。 相似文献
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废水矿物油采样与样品萃取张向东,李峰(山东省滨州地区环境监测站256614)废水矿物油的采样及样品萃取的乳化现象是影响油类测定结果的重要因素,如果水样采集不当,样品萃取过程中乳化现象处理不好,会对测定结果产生较大影响。1样品采集水中油类物质主要来自采... 相似文献
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采用液-液萃取-毛细管柱气相色谱法,分别用苯和甲苯作萃取剂,对测定水中4种硝基苯类化合物的方法进行比对分析。从精密度、准确度、方法检出限等方面对这2种方法进行系统比对,对实际水样测定结果采用统计学中t检验法进行比对。评价用甲苯代替苯作萃取剂的可行性。结果表明,用甲苯完全可以代替苯。 相似文献
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采用固相萃取-离子色谱法同时测定化工废水中乙醇胺、二乙醇胺、三乙醇胺、N-甲基二乙醇胺和N-丁基二乙醇胺等5种有机醇胺类化合物。通过试验,对固相萃取、离子色谱条件进行优化,优选C_(18)为固相萃取填料,使方法在1.10 mg/L~26.0 mg/L范围内线性良好,方法的检出限为0.72 mg/L~1.02 mg/L。废水样品3个质量浓度水平的加标回收率为84.0%~101%,测定6次结果的RSD为1.7%~12.0%。将该方法用于医药化工企业废水的测定,结果部分醇胺类化合物检出。 相似文献
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通过大量实验,研究建立了水体中9种酚类化合物同时测定的多个监测分析方法,包括液液萃取-气相色谱-氢火焰检测器法、液液萃取-气相色谱-质谱法、液液萃取-衍生化气相色谱-质谱法、固相萃取-液相色谱-紫外检测器法和固相微萃取-气相色谱-质谱法。研究表明各个分析方法均具有较高的灵敏度,方法检出限在0.03~2.5 μg/L之间,能满足相关环境工作的需要。经方法适用性和可操作性比较,推荐选择固相微萃取-气相色谱-质谱法用于应急水样的快速测定、固相萃取-液相色谱-紫外检测器法用于地表水等清洁水样的测定、液液萃取-气相色谱-氢火焰检测器法用于工业废水等污染水样的测定。 相似文献
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采用分散液液微萃取-气相色谱法测定地表水中松节油,通过试验优化萃取剂、分散剂的种类和用量、盐度等影响萃取效率的条件,使该方法在10.0μg/L~500μg/L范围内线性良好,方法检出限为1.6μg/L。用该方法测定实际水样,结果未检出。实际水样的3个质量浓度水平加标回收率为83.6%~104%,RSD为2.1%~8.3%。 相似文献
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土壤中石油类检测前处理方法的改进 总被引:1,自引:0,他引:1
以四氯化碳为萃取剂,选择振荡提取和浸泡提取两种前处理方法,采用红外光度法测定土壤中石油类.考察了两种提取方法对土壤样品测定结果的影响,推荐振荡提取时间为9h,振荡频率为150次/min;推荐浸泡提取时间为16 h. 相似文献
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研究了用超声波萃取城市污水处理厂污泥中动植物油和矿物油的方法,并与索氏提取法进行比较.结果表明,超声波萃取法对污泥中矿物油和动植物油测定操作简单快速,标样回收率高,精密度好. 相似文献
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Guerin TF 《Journal of environmental monitoring : JEM》1999,1(1):63-67
A sonication method was compared with Soxhlet extraction for recovering polycyclic aromatic hydrocarbons (PAH) from a clay soil that had been contaminated with tar materials for several decades. Using sonication over an 8 h extraction period, maximum extraction of the 16 US EPA priority PAH was obtained with dichloromethane (DCM)-acetone (1 + 1). The same procedure using hexane-acetone (1 + 1) recovered 86% of that obtained using DCM-acetone (1 + 1). PAH recovery was dependent on time of extraction up to a period of 8 h. The sonication procedure showed that individual PAH are extracted at differing rates depending on the number of fused rings in the molecule. Soxhlet extraction [with DCM-acetone (1 + 1)] over an 8 h period recovered 95% of the PAH removed by the sonication procedure using DCM-acetone (1 + 1), indicating that rigorous sonication can achieve PAH recoveries similar to those obtained by Soxhlet extraction. The lower recovery with the Soxhlet extraction was explained by the observed losses of the volatile PAH components after 1-4 h of extraction. The type of solvent used, the length of time of extraction and extraction method influenced the quantification of PAH in the soil. Therefore, the study has implications for PAH analyses in soils and sediments, and particularly for contaminated site assessments where the data from commercial laboratories are being used. The study emphasizes the importance of establishing (and being consistent in the application of) a vigorous extraction, particularly for commercial laboratories that handle samples of soil in batches (at different times) from a single site investigation or remediation process. The strong binding of PAH to soil, forming aged residues, has significant implications for extraction efficiency. This paper illustrates the problem of the underestimation of PAH using the US EPA method 3550, specifically where a surrogate spike is routinely employed and the efficiency of the extraction procedure for aged residues is unknown. The implications of this study for environmental monitoring, particularly where numerous batches of samples from a single site assessment or remediation program are submitted to commercial laboratories, is that it would be advisable for these laboratories to check their existing method's extraction efficiencies by conducting a time course sonication extraction on their particular soil to determine the optimum extraction time. 相似文献
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比较加压液体萃取法、超声波辅助萃取技术和微波辅助提取技术对公园地表土中多环芳烃的提取效率,并对目标化学成分进行分析鉴定。以超高效液相色谱-三重四极杆质谱作为分析方法,共分离检测出16种多环芳烃类化合物,分别为萘、苊、苊烯、氟、菲、蒽、荧蒽、芘、苯并[a]蒽、艹屈、苯并[b]荧蒽、苯并[k]荧蒽、苯并[a]芘、二苯并[a,h]蒽、茚并[1,2,3-cd]芘和苯并[ghi]苝。结果表明:加压液体萃取法、超声波辅助萃取技术和微波辅助提取技术均可以有效提取公园地表土中多环芳烃类成分。超高效液相色谱-质谱联用技术可以有效地分析公园地表土中多环芳烃类成分。 相似文献
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Dubravka Relić Dragana Đorđević Sanja Sakan Ivan Anđelković Ana Pantelić Ratomir Stanković Aleksandar Popović 《Environmental monitoring and assessment》2013,185(9):7627-7645
In this paper, the main objective was fractionation of Cd, Cu, Ni, Pb, Zn, Ca, Fe, and K in certificate material and sediment samples gathered from and around the Petrochemical Industry using the conventional, microwave and ultrasonic sequential extraction. Microwave oven and ultrasound bath were used as an energy source for achieving faster extraction. Additional heating and boiling of samples were avoided by using lower power and shorter time for microwave and ultrasound extraction. Precision and accuracy of procedure were evaluated by using certificate material (BCR701). Acceptable accuracy of metals (87.0–111.3 %) was achieved for all three-step sequential of conventional extraction protocol. An accuracy of the fourth step has been verified with two certificate materials: BCR143R and 146R. The range of total extracted metal concentrations from sediments was similar for all three extraction techniques. A significant high percentage of Cd, Cu, and Zn were obtained after extraction of the exchangeable and acid soluble sediment fraction. Principal component analysis of values obtained after determination of risk assessment code using conventional and ultrasound sequential extraction show similarity of these values. Accuracy, recovery, and risk assessment code values imply that ultrasound sequential extraction is a more suitable, accelerated sequential extraction procedure (30 min per extraction step) than microwave extraction in applied conditions. 相似文献
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Antimony speciation in terrestrial plants. Comparative studies on extraction methods 总被引:1,自引:0,他引:1
Miravet R Bonilla E López-Sánchez JF Rubio R 《Journal of environmental monitoring : JEM》2005,7(12):1207-1213
A suitable method for the extraction of antimony species from plant materials prior to IC-HG-AFS analysis is presented. The extraction efficiency with different extraction systems using various aqueous and aqueous/solvent mixtures was initially evaluated by analysing the Virginia Tobacco Leaves Certified Reference Material. The concentration of antimony extracted was compared with the total antimony content in the plant material measured by HG-AFS after focused microwave-acidic digestion using HNO3 and H2O2. The proposed extraction procedures were applied to antimony speciation in several plants from a natural terrestrial environment impacted by mining activities. End-over-end agitation (4 h) followed by sonication (1 h) extraction using 0.1 mol l(-1) citric acid was found to provide the best extraction efficiency while also giving reliable speciation information. Both inorganic and methylantimony species were found in the extractable portion of some terrestrial plants. 相似文献
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Ipolyi I Brunori C Cremisini C Fodor P Macaluso L Morabito R 《Journal of environmental monitoring : JEM》2002,4(4):541-548
Two alternative extraction methods--a routine ultrasonic bath and a microwave oven--were developed and optimized for their eventual exploitation in the three-stage sequential extraction procedure proposed by the European Standards, Measurements and Testing (S, M & T) Programme, formerly Bureau Communitaire de Reference (BCR), for the operationally defined speciation of Cd, Cr, Cu, Ni and Zn. The conventional BCR three-stage sequential extraction procedure was modified at each stage, applying ultrasonic or microwave devices in order to shorten the required 16 h of shaking in all three steps. The experimental tests and the optimization of the operating parameters were carried out on a highly homogenized estuarine sediment reference material (RM S7) prepared by the Joint Research Centre (JRC) of ISPRA. Extractable metal contents were measured by inductively coupled plasma-mass spectrometry (ICP-MS) and the results obtained in each fraction by all three methods were statistically compared for all the studied elements. The conventional and newly developed alternative extraction methods were finally compared by the analysis of BCR 601, which is certified for the three-step BCR sequential extraction procedure. According to the statistical evaluation of the results, the proposed accelerated sequential extraction methods are valid alternatives to conventional shaking, with much shorter extraction times. 相似文献