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Determination of polychlorinated biphenyl congeners in environmental samples

Journal of Environmental Sciences 1996年第1期8卷 57-65页

作者： Chu Shaogang Yang Chun Xu Xiaobai (Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences, Beijing 100085,China )

A modified separation method has been developed for determinating polychlorinated biphenyl congeners in environmental samples. Direct treatment of extract with concentrated HzSO4 was employed in the first step for removal of lipids and other interfering substances, then a joint column of alumina-silica gel(Ag+) was applied to separate PCBs fraction from HCH, DDT and its analogs. After this separation, the PCBs fraction was analyzed by capillary gas chromatography with ECD detector and confirmed by GC/MS. The recoveries of individual congeners in Aroclor 1254 through the separation are about 79%-84%. The method is very efficient and useful for determination of trace amount of PCB congeners in environmental samples.

关键词： polychlorinated biphenyl capillary gas chromatography environmental samples.

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Prediction of Stability for polychlorinated biphenyls in Transformer Insulation Oil Through Three-dimensional Quantitative Structure-activity Relationship Pharmacophore Model and Full Factor Experimental Design

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Chemical Research in Chinese Universities 2016年第3期32卷 348-356页

作者： XU Zheng CHEN Ying QIU Youli GU Wenwen LI Yu School of Electrical and Electronic Engineering North China Electric Power University Beijing 102206 t~ R. China Environmental Research Academy North China Electric Power University Beijing 102206 P. R. China

Based on the obtained data of half-lives（t1/2） for 31 polychlorinated biphenyl congeners（PCBs）, 3D quantitative structure-activity relationship（QSAR） pharmacophore was used to establish a 3D QSAR model to predict the t1/2 values of the remaining 178 PCBs, using the structural parameters as independent variables and lgt1/2 values as the dependent variable. Among this process, the whole data set（31 compounds） was divided into a training set（24 compounds） for model generation and a test set（7 compounds） for model validation. Then, the full factor experimental design was used to research the potential second-order interactional effect between different substituent positions, obtaining the final regulation scheme for PCB. At last, a 3D QSAR pharmacophore model was established to validate the reasonable regulation targeting typical PCB with respect to half-lives and thermostability. As a result, the cross-validation correlation coefficient（q2） obtained by the 3D QSAR model was 0.845（〉0.5） and the coefficient of determination（r2） obtained was 0.936（〉0.9）, indicating that the models were robust and predictive. CoMSIA analyses upon steric, electrostatic and hydrophobic fields were 0.7%, 85.9%, and 13.4%, respectively. The electrostatic field was determined to be a primary factor governing the tt/2. From CoMSIA contour maps, tl/2 increased when substi- tuents possessed electropositive groups at the 2＇-, 3-, Y-, 5- and 5＇- positions and electronegative groups at the 3-, 3＇-, 5-, 6- and 6＇- positions, which could increase the PCB stability in transformer insulation oil. Modification of two typical PCB congeners（PCB-77 and PCB-81） showed that the lgtl/2 for three selected modified compounds increased by 13%（average ratio） compared with that of each congener and the thermostability of them were higher, validating the reasonability of the regulatory scheme obtained from the 3D QSAR model. These results are expected to be beneficial in predicting tl/2 values of PCB homologues and d

关键词： polychlorinated biphenyl Stability Half-life Three-dimensional quantitative structure-activity relationship pharmacophore Insulation oil, Full factor experimental design

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Sonochemical Degradation of polychlorinated biphenyls in Aqueous Solution

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Chinese Chemical Letters 2003年第2期14卷 205-208页

作者： Xi Kui WANG Guan Hong CHEN Zhong Yan YAO College of Chemistry and Environmental Science University of JinanJinan 250022

polychlorinated biphenyl (PCB) is a kind of persistent and dangerous environmental pollutants. This paper presented the research result of sonochemical degradation of 2-chloro- biphenyl (2-CBP), 4-chlorobiphenyl (4-CBP) and 4,4-dichlorobiphenyl (4,4-CBP)in water. The ultrasonic degradation kinetics of 2-CBP, 4-CBP and 4,4-CBP in water were found to be first-order and the degradation rate coefficients are 3.69?0-2, 3.19?0-2 and 2.06?0-2 at 25?C for 2-CBP, 4-CBP and 4,4-CBP respectively. The influence of initial concentrations, reaction temperature on the ultrasonic decomposition of 2-CBP were also investigated.

关键词： polychlorinated biphenyl degradation sonochemistry 2-chlorobiphenyl.

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共平面与非共平面多氯联苯经不同CYP酶代谢活化为致突变物（英文）

共平面与非共平面多氯联苯经不同CYP酶代谢活化为致突变物（英文）

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2017环境与公共健康学术会议暨中国环境科学学会环境医学与健康分会、中国毒理学会生化与分子毒理专业委员会2017年年会

作者： Yungang Liu Guifang Jin Keqi Hu Yifan Wu Hansi Jia Department of Toxicology School of Public HealthSouthern Medical University

polychlorinated biphenyls(PCBs) are persistent organic pollutants and human carcinogens,currently still released from various human activities including e-waste *** PCBs may activate the aromatic hydrocarbon receptor and thus stimulate various cellular ***-coplanar PCBs,however,are supposed to exert carcinogenic effects after metabolic activation to mutagenic *** recently identified that some non-coplanar PCBs are potent promutagens subsequent to activation by human CYP2E1,as indicated by their induction of micronuclei and gene mutations in Chinese hamster V79-derived cells expressing human CYP2E1 and human hepatocyte(L-02) *** human CYP2E1-mediated mutagenicity of PCBs demonstrated structure-activity relationships featured by selective activation of congeners with one of the chlorine substituents being ortho-positioned(conferring a non-coplanar configuration).Particularly,induction of mutagenic responses to 2,3,4’-(PCB 22) and 2,3,3’-trichlorobiphenyl(PCB 20) in human CYP2E1-expressing V79-derived cells was more potent than that to iV-nitrosodimemylamine,a CYP2El-dependent *** the other hand,these non-coplanar PCBs showed no or weak activities in V79-derived cell lines expressing other CYPs,i.e.,human CYP1A1,1A2,1B1,or ***,PCB 20 and 22 induced micronuclei in L-02 cells,and this effect was blocked by specific CYP2E1 inhibition,wherein the effects of benzo[a]pyrene(activated by CYP1A1) and aflatoxin B(activated by CYP1A2 and CYP3A4) were *** 3,3’4,4’-tetra-(PCB 77)and 3,4,4’,5-tetrachlorobiphenyl(PCB 81) were both inactive in V79-derived cells expressing human CYP2E1;however,in the cell lines expressing human CYP1B1 or 1A2,coplanar PCB 81 and3,3’4,4’,5-pentachlorobiphenyl(PCB 126) induced micronuclei in a concentration-dependent manner,though they were inactive in the Hprt mutagenicity *** summary,our investigations suggest that both coplanar and non-coplanar PCBs are promutag

关键词： Cytochrome P450(CYP) Coplanarity Gene mutations Micronuclei polychlorinated biphenyl

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