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Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, china

Science china Earth Sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2 1. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, china 2. Laboratory for Earth Surface Processes, Peking University, beijing 100871, china 1. Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for Earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952―2003 were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952―1983, the average input and output amount of HCHs through agricultural application and degradation are 130 t and 150 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92% of total transfer fluxes of HCHs isomers. There were approximately 253t HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983, and this percentage may descend to 0.5% after 20 years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

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CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials Physics,University of Science and Technology beijing,beijing 100083,china

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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology beijing,beijing,china

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

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Characteristics of air particulate matter and their sources in urban and rural area of beijing, china

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Journal of Environmental Sciences 2000年第4期12卷 402-409页

作者： YANG Shao jin, DONG Jin quan, CHENG Bing ru (Institute of High Energy Physics, Chinese Academy of Sciences, beijing 100080, china) Institute of High Energy Physics Chinese Academy of Sciences Beijing 100080 China

During October 1993 and March 1996, the samples of fine and coarse air particulate matter have been collected at representative urban and rural site of beijing with the Gent Stacked Filter Unit Sampler. Instrumental neutron activation analysis (INAA) and proton induced X ray emission (PIXE) method were used to determine the elemental composition of the particulate matter. Average elemental concentrations and enrichment factors were calculated for the fine and coarse size fractions. Based on the particulate matter data obtained at urban and rural site together with the chemical constituents of the aerosol from the different sources are discussed. The results show that the relative particulate mass and elemental concentrations of crustal and pollutant elements in the air particulate matter collected over the urban are higher than rural and winter heating period are higher than in ordinary season. beijing atmosphere is polluted by aerosols from regional and faraway sources. It was noticed that the toxic or harmful elements such as As, Sb, Pb, Cu, Ni, S and Zn were mainly enriched in fine particles with diameter less than 2 μm. A receptor model was used to assess the relative contribution of major air pollution sources at receptor sites in beijing. Trace elements were used as the markers for the above assessment. Factor analysis method was used to identify possible emission sources of air particles. The major sources of dust soil, coal burning, motor vehicle emission, industry emission and refuse incineration were identified.

关键词： atmospheric particulate matter urban rural source aerosol

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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 Center for Eco-Environmental 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 13.20- 148.71 mg/kg, and 3.02-67.43 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

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Paleotemperature changes over the past 3000 years in eastern beijing, china: A reconstraction based on Mg/Sr records in a stalagmite

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Chinese Science Bulletin 2003年第4期48卷 395-400页

作者： MA Zhibang1, LI Hongchun2, XIA Ming1, KU Tehlung2, PENG Zicheng3, CHEN Yushu4 & ZHANG Zhaofeng3 1. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china 2. Department of Earth Sciences, University of Southern California, Los Angeles, CA90089-0740, USA 3. Department of Earth and Space Science, University of Science and Technology of china, Hefei 230026, china 4. beijing Foshan Tourist Service Centre, beijing 101201, china Institute of Geology and Geophysics. Chinese Academy of Sciences Beijing 100029 China

The Mg/Sr ratio in a stalagmite, which is di-rectly proportional to DMg/Ca, the solid-liquid distribution coefficient of Mg, is proposed as a geochemical thermometer to estimate paleotemperature changes. The paleotempera-ture change in eastern beijing over the past 3000 years has been reconstructed by using this thermometer in the stalag-mite ZFFS-1 from Jingdong Cave. The records can be di-vided into two periods: 3000—2000 aBP, cool and wet, the air temperature averaging 9.8℃; and 2000 aBP—present, hot and dry, the air temperature being 1℃ higher than the mean value (11.7℃) of the past 3000 years. During 500—200 aBP, the air temperature was about 1.2℃ lower than that of the present, corresponding to the Little Ice Age in Europe. Like d 18O and d 13C, Mg/Sr (or DMg/Ca) reflects an obviously warming trend of the past 200 years. These results are sup-ported by historic records.

关键词：北京京东溶洞石笋 Mg/Sr记录古气温测年 3000年

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

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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, Research 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 ecosystem, 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 （5.24–17.0 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 437 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 ecosystem.

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

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Fractal properties of patch perimeters in a disturbed montane landscape,beijing,china

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Journal of Environmental Sciences 1999年第2期11卷 68-72页

作者： Ma Ke ming, Fu Bo jie Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, beijing 100085, china

The forest landscape has been highly fragmented in Donglingshan montane region, beijing, china, where the folding degree of patch perimeters considerately influenced the spatial distribution of biological diversity, therefore the quantitative description to it is very helpful to conservation biology studies. The fractal dimensions of landscape patch perimeters of this region were estimated and compared. The results showed that fractal dimensions of all the landscape types were between 1.00 and 1.58. The fractal dimensions of natural vegetation types were higher than that of artificial vegetation type. Where forests (1 21) and shrubs (1.24) are near to farmland (1.12), so they were both highly disturbed by human activities regarding the smallest mean patch areas. But the grassland (1.58) had the largest mean patch area, its disturbance intensity was the lowest in this region. The fractal dimension of the overall landscape was 1.24, which was near to those of forests and shrubs, and obviously different from those of farmland and grassland. The fractal dimension of the overall landscape was 1.13 in small scales, and that was 1.65 in large scales. Which means that a large number of small area patches had regular perimeters, their fragment degrees were higher; whereas the large area patches had folding perimeters, their fragment degrees were lower, they had smaller patch numbers, however occupied most of the landscape area. Large areas and highly folded perimeters were the main property of the landscape patch in Donglingshan montane region.

关键词： beijing Dongling montane region landscape fragmentation patch perimeter fractal dimension.

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Lead and copper levels in tea samples marketed in beijing,china

Lead and copper levels in tea samples marketed in Beijing,Ch...

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中国食品科学技术学会第五届年会暨第四届东西方食品业高层论坛

作者： Fei Qin Wen Chen (beijing Key Laboratory of Bioactive Substances and Functional Foods,beijing Union University,beijing 100083,china)

Next to water,tea is the most widely consumed beverage(Marcos et al.1998),due to its taste aroma and health *** the basis of extensive animal experiments and some epidemiological data,tea has been considered to have lots of beneficial effects on preventing many diseases,including skin cancer(Katharin 2001),Parkinson’s disease(Richard 2001),myocardial infarction(Cheng 2003), and coronary artery disease(Hirano et al.2003).Tea is produced from the leaves of the tropical evergreen Camellia sinensis,which is indigenous to *** china,tea sipping is an integral part of the *** the world,china is a major tea producer,producing 23.3% of the world’s ***,the rapid industrialization of china over the last two decades has resulted in increased contamination to the environment,which inevitably brought contamination to *** the growth period of tea plant and tea processing,tea itself can be contaminated by heavy metals,such as lead and copper,which might increase the metal body burden in *** is a physiological and neurological toxin that can affect almost every organ and system in the human *** can reduce cognitive development and intellectual performance in children and damage kidneys and reproductive *** is an essential element, with both deficiencies and excesses being associated with impaired *** deficiency is known to cause various physiological disorders such as anaemia and bone abnormalities(Uauy et al.1998), resulting from decreased activity of the copper-requiring *** copper excess can cause hepatic and kidney damage,haemolytic anaemia(Evans 1973)and methaemoglobinaemia(Chugh et al. 1975).Therefore after pesticide contamination issue,heavy metal contamination in teas has become another noteworthy issue as they are directly related with heath and disease. The purpose of the present study was to(1)determine the lead and copper concentrations in tea samples collected from beijing market;(2)give an ove

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Spatial Prediction of Heavy Metal Pollution for Soils in Peri-Urban beijing, china Based on Fuzzy Set Theory

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Pedosphere 2006年第5期16卷 545-554页

作者： TAN Man-Zhi XU Fang-Ming CHEN Jie ZHANG Xue-Lei CHEN Jing-Zhong State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate school of the Chinese Academy of Sciences Beijing 100039 Chengdu University of Technology Chengdu 610059 （China） Nanjing Station of Soil and Fertilizer Nanjing 210036 （China）

Fuzzy classification combined with spatial prediction was used to assess the state of soil pollution in the peri-urban beijing area. Total concentrations of As, Cr, Cd, Hg, and Pb were determined in 220 topsoil samples （0-20 cm） collected using a grid design in a study area of 2 600 kin2. Heavy metal concentrations were grouped into three classes according to the optimum number of classes and fuzziness exponent using the fuzzy comean （FCM） algorithm. Membership values were interpolated using ordinary kriging. The polluted soils of the study area induced by the measured heavy metals were concentrated in the northwest corner and eastern part, especially the southeastern part close to the urban zone, whereas the soils free of pollution were mainly distributed in the southwestern part. The soils with potential risk of heavy metal pollution were located in isolated spots mainly in the northern part and southeastern corner of the study region. The FCM algorithm combined with geostatistical techniques, as compared to conventional single geostatistical kriging methods, could produce a prediction with a quantitative uncertainty evaluation and higher reliability. Successful prediction of soil pollution achieved with FCM algorithm in this study indicated that fuzzy set theory had great potential for use in other areas of soil science.

关键词： continuous classification fuzzy c-means heavy metal soil pollution spatial prediction

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Decline in the concentrations of chlorofluorocarbons(CFC-11,CFC-12 and CFC-113) in an urban area of beijing,china

Decline in the concentrations of chlorofluorocarbons(CFC-11,...

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中国科学院地质与地球物理研究所2007学术年会

作者： Dajun Qin Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing,china

During this study 352 whole air samples were collected in an urban area of beijing between January 2005 and March *** temporal variation of the concentrations of chlorofluorocarbons(CFCs:CFC-11,CFC-12,and CFC-113) in air in the beijing urban atmosphere is presented and *** weighted mean monthly values of these concentrations have been compared with the data from the north *** has been concluded that,in the observed period of time, the mean enhancement of CFCs was relatively small,with increase of 10-15%,with respect to the global background. Change rate in concentrations of CFCs is -1.39,-1.04,and -0.16pptv/month for CFC-11,CFC-12,and CFC-113, *** tendency of the CFC concentration of the three compounds toward background values is observed to fall and indicates that limitation of emission of CFCs is taking effect,under the Montreal Protocol.

关键词： Urban air CFCs Ozone depletion gases beijing

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