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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.

Influence of organic amendments on the sorption of pentachlorophenol on soils

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Journal of environmental sciences 2009年第4期21卷 474-480页

作者： LI Ruijuan, WEN Bei, ZHANG Shuzhen, PEI Zhiguo, SHAN Xiaoquan State Key Laboratory of environmental Chemistry and ecotoxicology, research center for eco-environmental sciences, chinese academy of sciences,beijing 100085, china State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The influence of pH on the sorption of pentachlorophenol （PCP） onto three organic amendments, char, humic acid （HA） and peat, and the effect of organic amendments on PCP sorption to three kinds of soils were evaluated. The sorption of PCP on these sorbents fitted the Freundlich model well, suggesting that PCP sorption isotherms were nonlinear with exponential coefficient （N） value lower than 1. The PCP sorption capacity on three organic amendments and the N values increased with decreasing pH. The sorption capacities were in the order： char 〉 HA 〉 peat. Organic amendments resulted in an enhancement of sorption capacities of soils. The N values of PCP sorption on soils were decreased by char amendment and increased by HA and peat amendments. This study demonstrated that application of traditional organic amendments led to the enhancement of PCP sorption by soils. This information may aid both in predicting environmental fates of hydrophobic ionizable organic compounds and in developing remediation strategies for them.

关键词： sorption pentachlorophenol char peat humic acid pH

A human－ecology approach to environmental design──An integrative human－ecology design derived from chinese agricultural cultur eexperiences

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Journal of environmental sciences 1994年第4期6卷 478-485,485页

作者： Hu Dan (research center for eco-environmental sciences , chinese academy of sciences , beijing 100085, china)

Based on fundamental principles of ecology ,the ecological philosophy connotation of Feng-Shui(Wind and Water) concept from experiences of chinese agricultural culture was first discussed , and then hu-man-ecological implications of Feng-Shui environment architecture is analyzed. As a theoretical integrationbetween human ecology and Feng-Shui theory ,“environment” and “environmental design” concepts were re-examined and given new definitions. With holistic principles of human ecological design in the context ofFeng-Shui , essential technical ways of integrative human ecological design were explored in the presentationof a case study of an urban environmental design in east china.

关键词： integrative environmental design human ecology Feng-Shui environment architecture.

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.

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 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

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.

Biologically effective radiation of solar ultraviolet radiation and the depletion of stratospheric ozone

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Journal of environmental sciences 1994年第3期6卷 373-381页

作者： Wang Shaobin Su Weihan(research center for eco-environmental sciences,chinese academy of sciences),beijing 100085,china) Wei Dingwen(Institute of Atmospheric Physics,chinese academy or sciences),beijing 100029,china)

Based on the biological action spectra and total UV-B radiation in the atmosphere,the effective UV-dose for DNA, erythema,and plant at different seasons in the last decade,and their future change in beijing area were *** results indicate that the maxi- mum of biologically effective radiation dose at noontime is in July and the minimum is in January. From 1980 to 1989 biologically effective radiation dose have increased with the average rates of about 0.6,0.7 and 1.1 mW/m￣2 per year for January, April and October,while in July the trend of radiation dose is not ln evidence. For 1% reduction of ozone concentration radiation amplification factor for DNA,erythema and plant are 2.3,2.3 and 1.4 and for 30% reduction of ozone concentration the RAF for DNA,erythema and plant are 4.2,4.0 and 2.1,respectively.

关键词： UV-B ozone depletion biological effects solar radiation.

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 State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 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

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. 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