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1.
探讨了在污染事故现场采用固相微萃取-车载气相色谱联用测定有机磷农药的分析方法,寻找出较适宜灵敏度与较短分析时间的最佳结合点,以适应污染事故应急现场测定有机磷农药的需求。该法完成一个样品的全部分析时问为30min,简便、高效,适用于应急现场5种有机磷农药的测定。  相似文献   

2.
测定南京某农药厂附近大米、蔬菜及肉类中11种有机磷农药含量,通过使用气相色谱/质谱联用的方法,建立GC/MS定性定量分析方法,检出限达到0.05μg/kg(肉类)和0.1μg/kg(大米和蔬菜),回收率均符合测定要求。环境样品监测结果显示,大米和蔬菜中有机磷农药的含量高于肉类中的含量,说明在大米和蔬菜表面残留的农药量要高于进入生物体体内的含量。南京蔬菜样品中有机磷农药高于常州蔬菜样品,说明农药厂对蔬菜表面残留农药量有影响。不同的有机磷农药在不同的介质中,检出情况不一样,说明不同的环境介质对有机磷农药的保留水平不一样。  相似文献   

3.
用HP6890气相色谱仪氮磷检测器(NPD)测定有机磷农药时,需购买高浓度标准贮备液,使用时进行稀释,实验中发现,稀释的介质对有机磷检测敏感性有一定影响,浓度越低,影响越大。  相似文献   

4.
采用固相微萃取-便携式气相色谱/质谱联用法(In situ SPME/GC-MS)分析地表水和废水中6种有机磷农药,通过优化测定条件,使6种有机磷农药在200 μg/L~500 μg/L范围内线性良好。方法检出限为033 μg/L~122 μg/L,低、高质量浓度标准溶液6次测定结果的RSD为68%~175%,加标回收率为849%~109%,与实验室方法的测定结果基本一致。  相似文献   

5.
气相色谱法测定土壤和沉积物中12种有机磷农药   总被引:1,自引:0,他引:1  
建立了索氏提取-固相萃取(SPE)小柱净化-GC-NPD测定土壤和沉积物中的12种有机磷农药的方法。用正己烷-丙酮(9:1)进行索氏提取,SPE硅胶小柱净化,15 mL乙酸乙酯洗脱。适用于土壤和沉积物的干样和湿样中12种有机磷农药的测定,取样量为10 g时,方法检出限为0.304~1.469 μg/kg,样品加标平均回收率为67.10%~109.8%,相对标准偏差为3.39%~14.7%。  相似文献   

6.
兰州市郊蔬菜基地土壤及蔬菜中有机农药污染现状调查   总被引:4,自引:0,他引:4  
通过对兰州市郊蔬菜基地土壤及蔬菜中,有机磷和有机氯农药残留量的测定,对其污染现状进行了综合分析。  相似文献   

7.
气相色谱法测定有机磷农药残留的常见问题探讨   总被引:1,自引:0,他引:1  
针对气相色谱法测定有机磷农药残留过程中常见的基线噪声大、活性位点吸附、热分解和基质效应等4个问题,从气相色谱仪的结构和有机磷农药的性质出发,探讨了解决办法。提出从气路故障、检测器、外部干扰等3个方面排查,降低基线噪声;正确使用玻璃衬管和色谱柱,消除活性位点;合理设置进样口和检测器温度,防止发生热分解现象;采用基质净化、基质匹配校准及加入分析保护剂的方法,避免基质效应。  相似文献   

8.
建立了一种非衍生—离子色谱—三重四极杆质谱法测定环境水样中有机磷(草甘膦、氨甲基膦酸、草铵膦、杀木膦和乙烯利)的方法。环境水样经RP-C18固相萃取柱和Ba柱除去杂质后,滤液无须衍生化,可直接进行定量分析。有机磷通过AS 19阴离子色谱柱分离,在负离子模式下以多反应监测方式(MRM)进行检测。结果表明,草甘膦、氨甲基膦酸和草铵膦在0.10~10.0 μg/L范围内的线性相关系数(r)均>0.999,检出限分别为0.02,0.03和0.03 μg/L,相对标准偏差(RSD)分别为2.8%~4.7%,5.4%~11.7%和5.1%~7.4%。杀木膦和乙烯利在0.02~2.00 μg/L范围内的 r 值均>0.999,检出限分别为0.007和0.004 μg/L,RSD分别为3.7%~5.8%和2.1%~13.2%。对实际水样进行测定,各目标物的加标回收率为70.0%~120%。该方法操作简便,精密度好,准确度高,适用于环境水样中5种极性有机磷的测定。  相似文献   

9.
采用二氯甲烷萃取水样,气相色谱-串联质谱法同时测定水中有机磷农药和甲萘威。试验表明:方法在20.0μg/L ~1000μg/L范围内,各目标化合物线性良好;方法检出限为0.004μg/L~0.01μg/L;对实际水样进行3个质量浓度水平的加标回收试验,回收率在71.8%~94.5%之间,RSD为3.7%~8.5%,满足水中痕量有机磷农药和甲萘威的测定要求。  相似文献   

10.
气相色谱-脉冲火焰光度检测器测定痕量有机磷农药   总被引:10,自引:0,他引:10       下载免费PDF全文
在水样和土壤样中分别加入二氯甲烷和丙酮,用超声波提取水样中敌敌畏、乐果、甲基对硫磷、马拉硫磷、对硫磷等5种有机磷农药和土壤样中甲拌磷、二嗪磷、异稻瘟净、杀螟农、溴硫磷、水胺硫磷、稻丰散、杀扑磷等8种有机磷农药,大大地简化了测定的预处理过程。应用气相色谱法HP—5石英毛细管柱分离,脉冲式火焰光度检测器检测,取得了较好的测定结果。水样中农药的检测限≤0.O02mg/L,土壤样中农药的检测限≤0.O02mg/kg,相对标准偏差水样<7%,土壤样<10%,加标回收率水样在84%—96%之间,土壤样在80%—108%之间,均满足测定要求。  相似文献   

11.
采用吹扫捕集-气相色谱质谱法对土壤和沉积物中挥发性有机物进行分析,优化了实验条件,所有物质的相对标准偏差小于5.0%,土壤样回收率在78.2% ~99.8%之间,沉积物样的回收率在55.2%~95.2%之间.  相似文献   

12.
土壤和河流沉积物中六六六和滴滴涕残留的测定   总被引:1,自引:0,他引:1  
采用密闭微波提取、超声波提取、索氏提取对土壤和河流沉积物进行前处理,提取液经弗罗里硅土柱净化或浓硫酸净化.通过回收率实验和精密度实验对三种提取方法和两种净化方法进行比较,建立了微波提取土壤和河流沉积物中六六六和滴滴涕,浓硫酸净化,气相色谱一质谱测定的分析方法,方法回收率在84%~110%之间,精密度(RSD)在2.8%~9.9%之间.采用该方法对阜阳市废弃农药厂周围的土壤和河流沉积物中六六六和滴滴涕进行了监测.  相似文献   

13.
土壤和沉积物中多氯联苯单体测定的净化方法研究   总被引:1,自引:0,他引:1  
对浓硫酸净化、铜粉脱硫、氟罗里硅土柱、硅胶柱、石墨碳柱等净化方法在土壤和沉积物多氮联苯单体测定中的应用进行了研究.浓硫酸对多氯联苯单体的净化回收率达92.4%~109%;氟罗里硅土柱用正己烷/丙酮混合溶液淋洗,净化洗脱液体积为8 mL~10 mL时,回收率达85.7% ~ 108%;硅胶柱用正己烷淋洗,净化洗脱液体积为...  相似文献   

14.
A solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) method for the simultaneous determination of the organophosphorus pesticides (OPPs), phorate, diazinon, methyl-parathion, fenitrothion, malathion, fenthion, ethyl-parathion and methidathion, has been developed to study their soil/water distribution. The method was used in conjunction with a conventional 'batch equilibrium method' to assess the soil adsorption coefficients (Koc) of the target compounds in different soil samples with known organic carbon content. Contrary to traditional techniques, the present method is fast, solvent-free and highly sensitive, thus permitting the assessment of the Koc values of the target compounds even at low soil concentration levels, close to those encountered in real field contamination, where the Freudlich adsorption isotherms can be considered to be linear. The estimated Koc values were found to be in good agreement with those reported in the literature.  相似文献   

15.
采用加速溶剂萃取-高效液相色谱法探究土壤和沉积物中11种均三嗪类农药测定相关保存条件。结果表明,在4℃以下避光、密封,标准贮备液可保存60 d;标准曲线系列溶液可重复使用11 d;阿特拉津等6种化合物的土壤样品可保存20 d,其他化合物可保存5 d~12 d;经过冷冻干燥处理,阿特拉津等7种化合物的沉积物样品可保存8 d,其他化合物可保存12 d;土壤提取液至少可保存60 d。  相似文献   

16.
建立了偏振能量色散X射线荧光光谱法测定土壤和沉积物中稀土元素的方法,该方法较传统的方法具有前处理简单、测量自动化程度高、灵敏度高和检出限低(检出限范围为0.05~2.80 mg/kg)等优点。对土壤和沉积物标准物质的测定结果表明:测定结果与认定值能较好吻合,相对标准偏差范围为0.2%~9.4%,能满足测试的需求。分别用该方法和电感耦合等离子体质谱法对实际样品进行测定,2种方法的测定结果有较好的一致性,表明该方法测定结果准确可靠,可用于实际样品的测定。  相似文献   

17.
研究了石油醚的吸收光谱 ,分析了泥沙对紫外分光光度法测定油污染物的影响 ,探讨了消除泥沙影响的方法 ,提出了紫外分光光度法测定黄河多泥沙水体中油污染物的改进方法。  相似文献   

18.
The sequential weight loss-on-ignition (WLOI) method for determination of organic and carbonate or inorganic carbon (C) content was evaluated on sediments from diverse sources with a great range of C contents. The sediments were collected from canal, wetland, river, estuary, lake, and marine sites. The organic and inorganic C contents of these samples ranged from 1 to 430 g kg???1 and from 4 to 97 g kg???1, respectively. Combinations of the combustion time and temperature and optimal weight ranges of representative samples were tested, and comparisons of the WLOI method with other methods, including dry combustion and wet combustion, were made. These methods were (1) use of the carbon?Cnitrogen?Csulfur (CNS) autoanalyzer with normal and reduced temperatures for total and organic C, (2) thermogravimetry for both organic and inorganic C, (3) use of the CNS autoanalyzer after removal of inorganic (carbonate) C by fumigating samples with concentrated HCl for organic C, (4) Walkley?CBlack wet combustion method for organic C, and (5) pressure-calcimeter associated with subtraction method (total C minus inorganic C) for organic C determinations. The results of analyzing samples of sediments of diverse origins showed that the optimal combination of temperature and time of WLOI depended mostly on the sources of the analyzed sediment. The WLOI analysis of sediment samples for organic C from wetlands, canal, estuary, or river sites needed a relatively low temperature but that of sediment samples from lake and marine sites required a relatively high temperature. Overall, to obtain reliable analysis results of samples from widely varied sediment sources except marine sediments, 500°C for 12 h was optimal for organic C content determination, and 800°C for yet another 12 h was optimal for inorganic C content determination. The temperature could even be reduced to 475°C if only wetland and stream sediments were included, but for marine sediments, 550°C for 12 h was necessary. Precise C content determinations for most sediment sources could be obtained by WLOI when sample quantities ranged from 2.0 to 4.0 g. The WLOI method, when conducted properly, resulted in precise measurements of C contents in ??standard samples?? used for calibration, and these values were closely comparable to results obtained with other dry combustion methods (R 2????0.96). We conclude that WLOI, which has advantages of simplicity, cost-effectiveness, and no waste disposal over other methods, can provide precise measurements of organic and inorganic C contents in sediments from a wide range of sources, but the selection of heating temperature and exposure time should be carefully considered based on sediment sources.  相似文献   

19.
A study was conducted to evaluate ten heavy metals in dry sediment samples used to assess the contamination of farmland in Niger Delta after a protracted flooding. Eighteen sediment samples in six locations were collected. Niger Delta is a major industrial area where Nigeria petrochemical company is located. These sediments were subjected to analysis using standard methods for the examination of the soil samples. Results showed a trend toward induction of environmental contamination with Zn, Cu, Fe, Hg and Pb on the farmland. Mercury and Lead are disproportionately higher than other sediment elements. Concentrations of these sediment elements are above compliance limit for Nigeria and these may have long-term adverse effects on soil and vegetation.  相似文献   

20.
Sixty home made wine and sixty-four grape samples were collectedfrom five territories in Jordan, where grapes and wine aremostly producted. The collected samples were analyzed for themost used organochlorine pesticides (OCP) and organophosphorouspesticides (OPP) in Jordan, as well as for four heavy metals(Ni, Cu, Zn and Pb). The results showed that OCPs residues weredetected in 73% of the wine samples but no OPPs residue weredetected which is due to generally shorter half life of thelater pesticide. Grapes showed higher incident of contaminationthan wine, however, OCPs and OPPs with both short and longhalf-lives were detected. The OPPs were detected in only8.3% of the analyzed grape samples. Heavy metals showed higher valuesin grapes than in the wine samples and it was attributed toremoval of solids during wine preparation processes or throughcontamination of wine during storage. Most of the samples werebelow toxic limit.  相似文献   

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