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Hydrolytic　dynamics　of　pesticide　N＇－（2，4－dimethylphenyl）－N－methylformamidine　in　aquatic　solution

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Journal of environmental sciences 1996年第2期8卷 185-190页

作者： Mo Hanhong Yang Kewu An Fengchun Liu Ye (Research center for eco-environmental sciences, chinese Academy of sciences, beijing 100085, china) Res. Ctr. for eco-Environ. sciences Chinese Academy of Sciences Beijing 100085 China

The hydrolytic dynamics of pesticide N' -(2,4-dimethylphenyl)-N-methylformamidine (DMA) in aquatic solution and its degradation in simulated aquatic ecosystem were investigated. The results showed that the compound was not very stable in aqueous solution and easily decomposed in alkaline solution. It was stable below pH5 and there was obvious tendency that the compound was easily decomposed when PH was greater than 6. The reaction rate constant of DMA increased with increasing of either pH value Or temperature of reaction medium. The half-life values of hydrolysis for DMA at 25℃ were 15. 92 days at pH 6, and 1. 40 days at pH 9 , respectively. The temperature coefficient and activation energy of hydrolysis for DMA was 2. 9 and 78. 74kJ. mol-1 , respectively. The degradation of DMA in simulated aquatic ecosystem was similar to that in buffer solution in the laboratory. The half-life values of degradation for DMA at 26℃ in simulated aquatic ecosystem were 3. 23 days at pH 9. 13 and 1. 41 days at pH 8. 28 , respectively.

关键词： pesticide N'- ( 2,4-dimethylphenyl)-N-methylformamidine hydrolysis degradation.

Levels and distributions of polychlorinated biphenyls in sewage sludge of urban wastewater treatment plants

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Journal of environmental sciences 2009年第4期21卷 468-473页

作者： GUO Li, ZHANG Bing, XIAO Ke, ZHANG Qinghua, ZHENG Minghui State Key Laboratory of environmental Chemistry and ecotoxicology, Research center for eco-environmental sciences, chinese Academy of sciences,beijing 100085, china [a]State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Concentrations of polychlorinated biphenyls （PCBs） have been measured in sewage sludge samples from 8 urban wastewater treatment plants in beijing, china. The PCB congeners were analyzed by isotope dilution high resolution gas chromatography/high resolution mass spectrometry method. The concentration of PCBs ranged from 65.6 to 157 ng/g dry weight （dw）, with a mean value of 101 ng/g dw. The dioxin-like PCB WHO-TEQs （World Health Organization-Toxic Equivalents） of the sludge were lower than 1 pg /g dw. Consequently, all the concentrations of PCBs in sludge samples were below the upper limit for land application according to the chinese legislation law for agriculture use. The PCB homologue profiles in sludge samples were dominated by tri-CBs and tetra- CBs. Similar distributions have been found in one of the chinese PCB commercial products. The patterns of dioxin-like and indicator congeners observed in this study were quite similar in all samples. The predominant congener for dioxin-like and indicator PCBs were PCB-118 and PCB-28, respectively, while PCB-126 had the highest TEQ value.

关键词： polychlorinated biphenyls wastewater treatment plant sewage sludge distribution

Synthesis of a magnetic micro/nano Fe_xO_y-CeO_2 composite and its application for degradation of hexachlorobenzene

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Science china Chemistry 2010年第6期53卷 1266-1272页

作者： JIA ManKe,SU GuiJin,ZHENG Minghui,ZHANG Bing & LIN ShiJing State Key Laboratory of environmental Chemistry and ecotoxicology Research center for eco-environmental sciences,chinese Academy of sciences,beijing 100085.china 1. State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A micrometer-sized nanostructured,magnetic,ball-like FexOy-CeO2 composite was synthesized through an ethylene-glycol mediated *** synthesized samples were characterized by scanning electron microscopy combined with energydisperse X-ray analysis,transmission electron microscopy and X-ray powder *** the synthesis system,polyethylene glycol (PEG) and urea were found to play significant roles in the formation of the micrometer-sized spherical architecture of the *** details of morphology and particle size could be changed with the initial concentration of Fe(NO3)3-9H2O and Ce(NO3)3-6H2O as the *** magnetic FexOy-CeO2 composite with a similar morphology was readily obtained by calcination from the *** characterization of transmission electron microscopy showed the calcined ball-like architecture was a highly porous structure consisting of many *** of the micrometer-sized nanostructure and the multi-components as well as the magnetism,the as-obtained FexOy-CeO2 composite showed better activity and potentially easy recovery for the harmless degradation of hexachlorobenzene (HCB).

关键词： FexOy-CeO2 composite 3D micro/nanostructures degradation of hexachlorobenzene

Debrominated and methoxylated polybrominated diphenyl ether metabolites in rainbow trout(Oncorhynchus mykiss) after exposure to decabromodiphenyl ether

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Journal of environmental sciences 2010年第9期22卷 1425-1434页

作者： Chenglian Feng,Yiping Xu,Yue He,Qian Luo,Jinmiao Zha,Zijian wang State Key Laboratory of environmental Aquatic Chemistry,Research center for eco-environmental sciences,chinese Academy of sciences,beijing 100085.china. [a] State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Decabromodiphenyl ether （BDE209） is the primary component in a commonly used flame retardant. Previous studies had proved that BDE209 itself was not toxic, while its metabolites including debrominated diphenyl ethers （De-BDEs） and methoxylated brominated diphenyl ethers （MeO-BDEs） posed a potential threat to organisms. Many studies had indicated that BDE209 could metabolize quickly in mammals, but lacking in the basic data about the metabolism of BDE209 in fish. In the present study, two replicate treatment groups of rainbow trout （Oncorhynchus rnykiss） were exposed to BDE209 via a single intraperitoneal injection approximately 100 and 500 ng/g, respectively. Muscle, liver and blood samples were collected to analyze the specific metabolites on day 1 and day 28 post injection. The highest concentration of BDE209 was detected in muscle tissues, from 796.1 ng/g wet weight （day 1） to 687.1 ng/g wet weight （day 28） in high dose group, suggesting that BDE209 could accumulate slightly in muscle tissues. However, BDE209 was not detected in the blood for all treatments. Most congeners of De-BDEs were found in muscle and liver tissues, with the highest concentration in the liver. The main De-BDEs were nona-, octa-, hepta- and penta-De-BDEs. A total of seven MeO-BDE metabolites were observed among different fish tissues. Blood had the highest contribution of the MeO-BDE metabolites. Each MeO-BDE congener increased over the 28 days. These results in contrast to other studies suggested possible species-specific differences in metabolic abilities.

关键词： decabromodiphenyl ether (BDE209) methoxylated brominated diphenyl ethers (MeO-BDEs) debrominated diphenyl ethers (De-BDEs) rainbow trout

Evaluation on abundance or deficiency of avai－lable trace elements in soil of middle area in china and the effect of applying trace element fertilizer

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Journal of environmental sciences 1994年第3期6卷 361-372页

作者： Li Jiyun Liu Xiudi Fan Lihong Tong Yiping Yang Junhui(Research center for eco-environmental sciences,chinese Academy of sciences,beijing 100085.china)

The authors selected the west part of Xinxiang City,Henan Province in the north china plain as a typical region and carried out assessments of the abundanca or deficiency of the trace ele- ments(B,Mn,Mo,Zn,Cu,Fe)in *** can be seen from results that more than 80% of the farmland is deficiency of zinc(<1.0ppm),40% of molybdenum(0.15ppm),38% of boron(0.5ppm),29% of manganese(100ppm)and 13% of iron(7.0ppm)and that the content of available trace ele- ments in soil are related to the topography *** the proper application of trace elements on grain crops is presented.

关键词： evaluation available trace element soil type topography.

On the determination of nitrous oxide emission factor during biomass burning

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Journal of environmental sciences 1994年第3期6卷 261-267页

作者： Cao Meiqiu Zhuang Yahui (Research center for eco-environmental sciences, chinese Academy of sciences) P. O. Box 2871,beijing 100085.china

The emission factors of nitrous oxide have been determined during the combustion of rice straws, maize stalks and wheat stalks in an enclosed combustion system. They equal to 84.4 ± 6.08g/t for rice straws,132± 8.63g/t for maize stalks,and 27.3 ±1.79g/tfor wheat stalks,respectively. The uncertainties in the determination of nitrous oxide have been discussed. The N_2O-N(nitrogen in nitrous oxide emission)accounts for 0. 59% and 0. 87% of the total nitrogen in rice straws and maize stalks,respectively. An 1￣0 ×1￣0 grid map on the distribution of N_2O emission from biomass burning in china mainland was shown.

关键词： biomass burning,nitrous oxide emission factor

A numerical simulation of kinetic constraint on evaporation of ammonium nitrate in diffusion denuder

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Journal of environmental sciences 1998年第1期10卷 115-123页

作者： Shen Ji Research center for eco environmental sciences, chinese Academy of sciences, beijing 100085, china

A numerical simulation model has been developed to investigate the diffusion and reaction in diffusion denuder for reactive gases and aerosols. The analytical equation for equilibrium and kinetic equations of NH 4NO 3, NH 3 and HNO 3 system were presented. The model results of sampling efficiencies were agree with those calculated by Gormley Kennedy equation and other models. The evaporation of NH 4NO 3 aerosol has a kinetic constraint. The kinetic constant can be estimated from evaporation data. The model results showed that an annular denuder can separate reactive gases and aerosols.

关键词： kinetic constraint ammonium nitrate diffusion denuder.

Adsorption of atrazine by natural organic matter and surfactant dispersed carbon nanotubes

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Journal of environmental sciences 2010年第8期22卷 1195-1202页

作者： Baoyou Shi, Xiaoyan Zhuang, Xiaomin Yan, Jiajuan Lu, Hongxiao Tang State Key Laboratory of environmental Aquatic Chemistry, Research center for eco-environmental sciences, chinese Academy of sciences, beijing 100085, china. [a] State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The aggregation and dispersion behaviors of carbon nanotubes （CNTs） can regulate the environmental spread and fate of CNTs, as well as the organic pollutants adsorbed onto them. In this study, multi-walled carbon nanotubes （MWNTs） and single-walled carbon nanotubes （SWNTs） were surface modified with humic acids from different sources and with surfactants of different ionic types. The dispersion stability of surface modified CNTs was observed by UV-Vis spectrophotometry. The effect of humic acid and surfactant dispersion on the adsorption of atrazine by CNTs was investigated by batch equilibrium experiments. Both humic acid and surfactant could effectively disperse MWNTs, but not SWNTs, into stable suspensions under the studied conditions. Surface modified CNTs had a greatly reduced capacity for adsorption of atrazine. The inhibitory effect of peat humic acid was relatively stronger than that of soil humic acid, but the two surfactants had a similar inhibitory effect on atrazine adsorption by the two CNT types. Increases in surfactant concentration resulted in rapid decreases in the adsorption of atrazine by CNTs when the surfactant concentration was less than 0.5 critical micelle concentration.

关键词： carbon nanotubes adsorption dispersion atrazine

The associations between the environmental exposure to polychlorinated biphenyls (PCBs) and breast cancer risk and progression

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Science china Chemistry 2010年第5期53卷 974-979页

作者： LIU SiJin ,ZHANG ShuPing,QU Chen,LIU Wei & DU YuGuo State Key Laboratory of environmental Chemistry and ecotoxicology Research center for eco-environmental sciences,chinese Academy of sciences,beijing 100085.china 1. State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Polychlorinated biphenyls(PCBs) are chlorinated biphenyl compounds with wide applications in the *** spite of a ban on their production in the late 1970s,PCBs,as a group of POPs,are still persistent and widely spread in the environment,posing potential threats to human *** role of PCBs as etiologic agents for breast cancer has been intensively explored in a variety of in vivo,animal and epidemiologic *** investigations indicated higher levels of PCBs in mammary tissues or sera corresponded to the occurrence of breast cancer,but later studies showed no positive association between PCB exposure and breast cancer *** recent data suggested that the CYP1A1 m2 polymorphisms might add increased risk to the etiology of breast cancer in women with environmental exposure to *** are implicated in advancing breast cancer progression,and our unpublished data reveals that PCBs activate the ROCK signaling to enhance breast cancer ***,the correlation between PCB exposure and breast cancer risk warrants further careful investigations.

关键词： Polychlorinated biphenyls (PCBs) environmental exposure CYP1A1 polymorphisms breast cancer risk tumor progression