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Journal of environmental sciences 1998年第2期10卷 83-88页

作者： Wu Gang Department of Systems ecology, research {2. for eco {4. sciences, Chinese academy of sciences, beijing 100085, china Department of Systems ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

In accordance with principles and methods of ecology, the effects of acidic deposition on productivity and volume increment of masson pine and Cinnamomum campora forest which are widely distributed in southern suburbs of Chongqing, china were studied. Based on the field data and measurements, a multivariable stepwise regression model was established to analyze the effects of multiple {2. factors on the productivity of the forest ecosystems. This model was used to assess the volume and economic losses of these two forest ecosystems caused by acidic deposition. The result showed that, among the {2. factors, pH value of precipitation, soil depth, soil organic contents and slope are the dominant ones influencing the growth of masson pine forest. It was also shown that the acidic deposition has no clear relation to the growth of *** forest, so development of such broad leaved forest is suitable in the area.

关键词： acidic deposition productivity volume increment economic loss.

Virus rejection with two model human enteric viruses in membrane bioreactor system

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Science china Chemistry 2007年第3期50卷 397-404页

作者： ZHENG Xiang1,2.& LIU JunXin1 1 research center for {2.-environmental {4., Chinese academy of {4., beijing 100085, china 2.School of Environment & Natural Resources, Renmin University of china, beijing 100872. china 1. research center for {2.-environmental {4. Chinese Academy of Sciences Beijing 100085 China 2. School of Environment & Natural Resources Renmin University of China Beijing 100872 China

A membrane bioreactor (MBR) with gravity drain was tested for virus rejection with two coliphages, T4.and f2. which were used as surrogates for human enteric viruses. Virus rejection was investigated by PVDF and PP membrane modules, with the pore sizes of 0.2. and 0.1 μm, respectively. In tap water system, 2.1 lg rejection of coliphage T4.could be achieved by PVDF membrane compared with complete rejection by PP membrane, while for coliphage f2.with smaller diameter, 0.3―0.5 lg rejection of the influent virus was removed by the two membranes. In domestic wastewater system, cake layer and gel layer on the membrane surface changed the cut-off size of the membrane so that there was no significant difference between PP and PVDF for each coliphage. The removal ratios of coliphage T4.and f2.in the MBR were more than 5.5 and 3.0 lg, respectively. Compared with 5.5 lg removal for virus T4.in the MBR system, only 2.1 lg (96.8%―99.9%) removal rate was observed in the conventional activated sludge system with the influent virus concentration fluctuating from 1830 to 57000 PFU/mL. Only 0.8%―2.% virus removal was the effect of adsorption to activated sludge, which showed a decreasing tendency with the retention time, while 75%―98% was the effect of virus inactivation by microbial activity. It indicated that the major mechanism of virus removal was not the transfer of viruses from the water phase to the sludge phase but inactivation in the biological treatment process.

关键词： MBR model virus enteric virus inactivation

Temperature-controlled ionic liquid dispersive liquid phase microextraction combined with ultra-high-pressure liquid chromatography for the rapid determination of triclosan,triclocarban and methyl-triclosan in aqueous samples

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Science china Chemistry 2010年第12期53卷 2600-2607页

作者： GUO JieHong 1,2.LI XingHong 2.CAO XueLi 1,QU Lei 2.3,HOU DeKun 2.& XU XiaoBai 2.1 School of Chemical and environmental Engineering,beijing Technology and Business University,beijing 10004.,china 2.State Key Laboratory of environmental Chemistry and eco-toxicology research center of eco-environmental sciences,Chinese {12. of sciences,beijing {14.,china 3 Zhengzhou University,Zhengzhou 4.0001,china 1. School of Chemical and environmental Engineering Beijing Technology and Business University Beijing 100048 China2. State Key Laboratory of Environmental Chemistry and Eco-toxicology research center of {2.-environmental {4. Chinese Academy of Sciences Beijing 100085 China3. Zhengzhou University Zhengzhou 450001 China

As extraction solvents,ionic liquids have green *** this study,an environmentally benign analytical method termed temperature-controlled ionic liquid dispersive liquid phase microextraction (TIL-DLME) combined with ultra-highpressure liquid chromatography (UHPLC)-tunable ultraviolet detection (TUV) was developed for the pre-concentration and determination of triclosan (TCS),triclocarban (TCC) and methyl-triclosan (M-TCS) in water *** parameters that may affect extraction efficiencies were examined and optimized,including the types and amount of ionic liquids,volume of the diluent,heating temperature,cooling time,salt effect and pH *** the optimum conditions,linearity of the method was observed in the ranges of 0.0100-100 μgL-1 for TCS and M-TCS,and 0.00500-50.0 μgL-1 for TCC with correlation coefficients (r2. > *** limits of detection (LODs) ranged from 1.15 to 5.33 *** in domestic water and TCC in reclaimed water were detected at the concentrations of 1.01 and 0.12. μgL-1,*** spiked recoveries of the three target compounds in reclaimed water,irrigating water,waste water and domestic water samples were obtained in the ranges of 68.{2.-71.9%,61.6%-87.8%,58.9%-7{2.9% and 6{2.9%-92.{2.,*** with the previous dispersive liquid-liquid microextraction method (DLLME) about the determination of TCS,TCC and M-TCS,this method is not only more environmentally friendly but also more sensitive.

关键词： ionic liquid temperature-controlled ionic liquid dispersive liquid phase microextraction UHPLC aqueous samples

Distribution and health risk assessment of organochlorine pesticides(OCPs) in industrial site soils:A case study of urban renewal in beijing,china

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Journal of environmental sciences 2009年第3期21卷 366-372页

作者： YANG Wenrui,WANG Rusong,ZHOU Chuanbin,LI FengState key laboratory of Urban and Regional ecology,research {2. for eco-{4. sciences,Chinese academy of sciences,beijing 100085,china. [a]State key laboratory of Urban and Regional ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A field survey was conducted in a contaminated industrial site of southern beijing, china to investigate the contents and distribution of the organochlorine pesticides （α-, β-, y-, δ-HCH, p,p＇-DDT, p,p＇-DDE, p,p＇-DDD and o,p＇-DDT） in the profiles of soil, and a health risk assessment was carded out with CalTOX multimedia exposure model. Results showed that mean concentrations of total hexachlorocyclohexane isomers （HCHs） and total dichlorodiphenyltrichloroethane isomers （DDXs） in soils were in the range of 13.2.- 1{2..71 mg/kg, and 3.02.67.{2. mg/kg, respectively. Organochlorine pesticides （OCPs） content peaked in the surface and declined in soil profile with depth. The amounts of HCHs in three profiles of soil were larger than DDXs. Composition analysis indicated that there was a trend of degradation of OCPs in the site, but the mean of HCHs and DDXs concentration were over the state warning standard limit （HCHs, 0.50 mg/kg; DDXs, 0.50 mg/kg）. According to current land use development, health risk assessment with CalTOX and Monte Carlo analysis showed that health risks mainly came from two exposure pathways： dermal uptake and inhalation, and the total risk values all exceeded the general acceptable health risk value （10-6）. The sensitivity analysis indicated that five parameters significantly contributed to total risk.

关键词： pollution hexachlorocyclohexane isomers (HCHs) dichlorodiphenyltrichloroethane isomers (DDXs) soil profiles Monte Carlo sensitivity

Effects of ground-level ozone (O_3) pollution on the yields of rice and winter wheat in the Yangtze River Delta

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Journal of environmental sciences 2003年第3期15卷 360-362页

作者： FENG Zong-wei, JIN Ming-hong, ZHANG Fu-zhu, HUANG Yi-zong (research center for {2.-environmental {4., Chinese academy of {4., beijing\ 100085, china.) research center for {2.-environmental {4. Chinese Academy of Sciences Beijing 10085 Chin

Effects of elevated O_3 on the yields of rice and winter wheat were studied by using open-top chambers(OTCs). Results showed that compared to the control treatment, 2.0 ppb, 100 ppb, 50 ppb treatments caused a 80.4., 58.6% and 10.5% decrease in grain yields per winter wheat plant and a 4..1%, 2..1% and 8.2. decrease in grain yield per rice plant, respectively. According to the dose-response relation educed from OTCs experiment and the monitor data of O_3 concentrations in spots, it was estimated that the yield losses of rice and winter wheat resulted by O_3 pollution in the Yangtze River Delta region in 1999 were 0.599 million ton and 0.669 million ton, {2.nomic losses were 0.539 billion RMB Yuan and 0.936 billion RMB Yuan, respectively.

关键词： rice winter wheat O_3 Yangtze River Delta

Comprehensive assessment of heavy metal pollution in river and lake sediments using face graph and index of geoaccumulation

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Journal of environmental sciences 1997年第1期9卷 40-48页

作者： Liu Wenxin Tang Hongxiao Luan Zhaokun research center for {2.-environmental {4.,Chinese academy of {4.,beijing 100085,china Res. Ctr. for eco-Environ. sciences Chinese Academy of Sciences Beijing 100085 China

Surface sedimental samples were collected from(1)Le An River in Jiangxi Province, south of china,and(2.several lakes located in southwest of *** of heavy metals in these samples were ***,the situations of heavy metal pollution in two regions were comprehensively assessed by combined index of geoaccumulation with visualized multi- variate graphical method——modified Chernoff Face *** graphs intuitively demonstrated strong heavy metal contamination in Le An River,especially copper ***,in lakes' sedimental samples,contamination of other heavy metals showed mild or clean except cadmium and chromium.

关键词： heavy metals sediment assessment index of geoaccumulation face graph.

Effect of atmospheric aerosols on UV-B radiation reaching the ground

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Journal of environmental sciences 1993年第2期5卷 224-229页

作者： Wang Shaobin Su Weihanresearch center for {2.-environmental {4., Chinese academy of {4., beijing 100085, china research center of {2.-environmental {4. Chinese Academy of Sciences Beijing 100085 China. China

Solar ultraviolet radiation reaching the ground can be reduced due to light scattering of atmospheric aerosols. Aerosol pollution has led to the decrease in biological active UV-B radiation by about 4.% and 10% in city and rural areas, respectively. In populated areas, effect of aerosol scattering on UV-B radiation may offset the increased amount of UV-B caused by ozone depletion, but in clean areas such as two poles, ozone depletion may have great damage effects on ecosystems.

关键词： atmospheric aerosol UV-B radiation ozone reduction.

Trophic transfer of mercury and methylmercury in an aquatic ecosystem impacted by municipal sewage effluents in beijing,{2.

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Journal of environmental sciences 2010年第8期22卷 1189-1194页

作者： Jianjie Fu, Yawei Wang, Qunfang Zhou, Guibin Jiang State Key Laboratory of environmental Chemistry and ecotoxicology, {2. center for eco-environmental sciences, Chinese academy of sciences, beijing 100085, china. [a] State Key Laboratory of environmental Chemistry ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Gaobeidian Lake, located in beijing, china, serves as a recipient lake for efluents from a large municipal sewage treatment plant （MSTP）. In order to evaluate the effects of discharging MSTP efluent on the mercury contamination of the local aquatic {2.system, sediment cores, water, plankton, fish, and turtle samples were collected from Gaobeidian Lake for mercury speciation analysis. High concentrations of total mercury （T-Hg） were detected in sediment cores （5.2.3}17.0 μg/g dry weight （dw）, average： 10.1 μg/g）. The ratio of methylmercury （MeHg） to T-Hg was less than 0.3% in sediments and ranged from 35% to 76% in biota samples. The highest level of T-Hg and MeHg were found in aquatic bryophyte and crucian carp （3673 and 4.7 ng/g dw, respectively）. The relative contents of MeHg were significantly correlated with trophic levels （R2.= 0.5506, p 0.001）, which confirmed that MeHg can be bio-transferred and biomagnified via food chain in this aquatic {2.system.

关键词： methylmercury total mercury trophic levels aquatic ecosystem municipal sewage treatment plants

Biologically effective ultraviolet radiation in beijing area

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Journal of environmental sciences 1993年第2期5卷 216-223页

作者： Wang Shaobin Su Weihanresearch center for {2.-environmental {4., Chinese academy of {4., beijing 100085, china research center for {2.-environmental {4. Chinese Academy of Sciences Beijing 100085 China. China

Ozone layer depletion implies the enhancement of solar ultraviolet radiation at the earth's surface. However, aerosol contributes to the scattering of solar radiation and leads to the reduction of UV-B radiation on the ground. In this paper, the model calculation shows that due to effects of atmospheric ozone and aerosol UV-B radiation in beijing in the past decade has decreased with the annual change rate of 0.7%, which is probably approximate to the measured values. The effects of three scenarios for long-term changes in atmospheric ozone and aerosol concentrations on UV-B radiation reaching the ground in are also discussed.

关键词： UV-B biological efftent zone aerosol beijing.

Coulometric determination of sulfur speciation in natural waters

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Journal of environmental sciences 1996年第4期8卷 491-498页

作者： Li Yuxian Zeng Yu Yan Huiyu(research center for {2.-environmental {4.,Chinese academy of {4., beijing 100085,china) Res. Ctr. for eco-Environ. sciences Chinese Academy of Sciences Beijing 100085 China

A systematic analytical method for the species of trace sulfur in water has been developed by using electrochemically coulometric titration in combination with several separation and concentration *** on the reaction of iodine with sodium azide,the studies were carried out on the catalytically coulometric determination of ppb levels of ionic or molecular sulfides,thiosulfates and hydrogen sulfide in wateri constant current coulometric determination of sulfites;and indirect coulometric determination of sulfate salts and *** with the determination of the content of total sulfur,the scope of distribution of the species of inorganic sulfur(including trace sulfur compounds in labile state)and organic sulfur in water was *** method thus developed was found to be featured by being easy and reliable to operate with a higher sensitivity and reproducibility and to be applicable to the analysis of sulfur species in water.

关键词： sulfur analysis of species electrochemical technique catalytically coulometric titration indirect coulometric titration.