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The study for polyaromatic hydrocarbons decay on Chinese coal soot particles in atmosphere

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Journal of environmental sciences 1991年第3期3卷 71-80页

作者： Shu Yonghui, Li Jinhua and Wang WenxingChinese research Academy of environmental {2.,beijing 100012.china

A study for the photochemical behavior of some polyaromatic hydrocarbons (PAH), for example B(a )P, B( k )F and fluoranthene in coal smoke particles was performed by using indoor Teflon smog *** suggest that the photochemical reaction of PAH is first order reaction and kinetic rates of some PAH were obtained. It was shown that the reaction rate constant is proportional to light intensity and water vapor concentration. Temperature and PAH loading also have influence on PAH decay rate. A model for PAH loss has been set up on the basis of the results of our experiments and the simulating results of this model suggest that coal particle PAH half lives are of the order of a period of days in winter and a few hours in summer. Other factors which may have effect on the photochemical reaction of PAH have also been discussed.

关键词： PAH photochemical reaction smog chamber kinetic rates.

A preliminary study on the characteristics of fogwater in the masson pine forest in Chongqing, china

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Journal of environmental sciences 1991年第2期3卷 11-16页

作者： Liu Houtian and Du XiaomingInstitute of Ecology,Chinese research Academy of environmental {2.,beijing 100012.china

The masson pine (Pinns massoniana Lamb.) forest of 2.00 ha situated on Nanshan, the south bank of the Yangtze River near Chongqing, china. From 1982. some trees began to die. Since then, half of the trees have died and the whole forest is in danger. Prom November 1986 to January 1987, a study dealt with the characteristics of fogwater in that area was carried out, in order to explain the relationship between acid fog and masson pine decline. The results of our study showed that the acid fog might be responsible in part for the decline of the masson pine forest.

关键词： acid fog masson pine forest particulate matter.

ECSTM study of adsorption of C_(60),C_(70),C_(86) and Y@C_(82. on Au(111)

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Science china Chemistry 2010年第8期53卷 1705-1710页

作者： SU GuiJin1,JIA ManKe1,GAN LiHua2.& SHI RuiFang1 1State Key Laboratory of environmental Chemistry and Ecotoxicology research Center for Eco-environmental sciences,Chinese Academy of sciences,beijing 100085,china 2.chool of Chemistry and Chemical Engineering,Southwest University,Chongqing 400715,china 1. State Key Laboratory of environmental Chemistry and Ecotoxicology research Center for Eco-environmental {2. Chinese Academy of Sciences Beijing 100085 China2. School of Chemistry and Chemical Engineering Southwest University Chongqing 400715 China

The adsorption of a variety of fullerenes (C60,C70,C86,Y@C82. on Au(111) electrode surfaces was comprehensively investigated in 0.1 M HClO4 by electrochemical scanning tunneling microscopy (ECSTM).In the ordered C60's adlayer,C60 molecules formed either (2.1/3) × 2.3～(1/3))or "in-phase" *** high resolution STM image shows that the C60 cage is not simply round but shows a bifurcated *** adsorption orientation of C60 on Au(111) is tentatively *** the ordered C70's adlayer,the perpendicular fullerene molecules are the main adsorption mode and form (2.3～(1/3) × 2.3～(1/3)) ***,for C86 and Y@C82.the ordered adlayer could not be obtained on Au(111) under the present *** differences may be due to the different molecular shapes and sizes,and the encapsulated metal atom which affects the lattice matches with the *** adsorption of fullerene molecules on Au(111) from disorder to order could be tuned simply by steering the dimensional sizes or shapes of the fullerenes used.

关键词： C60 C70 C86 Y@C82 ECSTM Au(111)

Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science china Earth sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5, LIU Linshan1, 2.& ZHENG Du1 1. Institute of Geographic sciences and Natural Resources research, Chinese Academy of sciences, beijing 100101, china 2. Graduate School of the Chinese Academy of sciences, beijing 100039, china 3. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716, china 4. The Ministry of Science and Technology, P. C. china, beijing 100862. china 5. Chengdu Institute of Biology, Chinese Academy of sciences, Chengdu 610041, china 1. Institute of Geographic sciences and Natural Resources research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the Chinese Academy of sciences 100039 Beijing China 3. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of Science and Technology P. C. China 100862 Beijing China 5. Chengdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

Changes in hair arsenic concentration in a population exposed to heavy pollution:Follow-up investigation in Chenzhou City,Hunan Province,Southern china

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Journal of environmental sciences 2010年第2期22卷 283-289页

作者： Bin Wu,Tongbin Chen Center for environmental Remediation,Institute of Geographic sciences and Natural Resources {2.,Chinese Academy of sciences,beijing 100101,china. [a] Center for environmental Remediation Institute of Geographic Sciences Natural Resources research Chinese Academy of Sciences Beijing 100101 China

Follow-up investigation on hair arsenic concentration was conducted in an arsenic heavily polluted area of southern china in 2.02.and 2.06. The results showed that the geometric mean of hair arsenic concentration decreased from 2.95 mg/kg in 2.02.to 1.78 mg/kg in 2.06, when the percentage of the population with levels over 1 mg/kg only decreased from 93.4% in 2.02.to 80.5% in 2.06. Over this four-year period, the population with high arsenic concentrations decreased significantly while there was no obvious change in hair arsenic concentration for people who had relatively low concentrations. In terms of age distribution, young and old people had higher hair arsenic concentrations than the middle-aged. All of these results showed that it is difficult to reverse the negative impact of arsenic pollution on human health. Arsenic pollution has a long-term continuous influence on the health of local residents.

关键词： arsenic human health soil contamination hair arsenic

Emissions of non-methane hydrocarbons from cars in china

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Science china Chemistry 2010年第1期53卷 263-272页

作者： DAI TianYou,WANG Wei,REN LiHong,CHEN JianHua & LIU HongJie Chinese research Academy of environmental Science,{2. 100012.china 1. Chinese research Academy of environmental Science Beijing 100012 China

This study investigated the exhaust emission of non-methane hydrocarbons(NMHCs) from cars in china at the beijing driving cycle on the chassis *** emission factor average of NMHCs was 0.9 g/km,which was over twice that from the Australian car fleet and 2.4 times that of the American car emission in the *** emission profile of beijing cars showed higher fractions of aromatics and C4?C7 HCs,and lower percentages of C2.C3 HCs,compared with those of the US car *** average ratio of benzene/toluene for cars tested was 0.5,the average benzene/toluene/ethyl benzene/xylenes(BTEX) ratios were 1/2.2.0.1/1.8,which were consistent with those of the Tanyugou tunnel located in the suburb of beijing.α-pinene and β-pinene were detected from the exhaust gas on dynamometer for the first time,and had likely similar exhaust emission characteristics with C2.C3 HCs and styrene,giving an evidence that air pinenes may be related to human *** was also detected *** observations suggest that the procedure regarding pinenes and isoprene as coming from biologic sources of VOCs in the atmosphere should be applied with great care,especially in the core of the big city like *** specific reactivity of NMHCs was higher than that of cars of US,and the specific reactivity of volatile aromatic compounds was higher than that of the US SPECIATE database.

关键词： emission factor isoprene pinene photochemical reactivity beijing driving cycle car

Agro-ecological engineering in china: a way towards sustainable agriculture

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Journal of environmental sciences 2000年第4期12卷 422-429页

作者： LIU Guo\|hua, FU Bo\|jie (research Center for Eco environmental {2., Chinese Academy of {2., beijing 100085, china) research Center for Eco-environmental {2. Chinese Academy of Sciences Beijing 100085 China

Sustainable development, as a “hot topic”, concerns not only economic development but also environmental protection. Agriculture, the base of other economic activities, has faced many difficulties that include over growth population, land decrease, and land degradation and so on. Therefore, how to increase the food supply, to meet the over\|growth population demands, is the main task all over the world at present, especially in the developing countries, such as china, but we also must protect agricultural environment for medium\| and long\|term development simultaneously. Hence, sustainable development in agriculture is the most important estate that we must concern. Its sustainable development determines the sustainability of other economic development to a great extent. Despite Chinese government has paid much attention to develop agricultural production and obtained great successions, there are also many shortcomings in Chinese agriculture. Therefore, china must seek new approaches for its development and environmental protection that suit local conditions and are based on local resources. Agro ecological engineering, the application of ecological engineering in agriculture, is very thriving in china in recent decades. In this paper, the ecological, economic and social benefits of agro\|ecological engineering are analyzed. The principles are discussed. The results indicated that agro\|ecological engineering can meet the farmer′s short\|, medium\| and long\|term benefits. In the meanwhile, it also concerns not only economic benefits but ecological and social benefits. Therefore, agro\|ecological engineering is a way that leads to sustainable agriculture in the future in china.

关键词： agro-ecological engineering sustainable agriculture sustainable development china

Applications of synchrotron-based X-ray techniques in environmental science

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Science china Chemistry 2010年第12期53卷 2529-2538页

作者： LUO Lei & ZHANG ShuZhen 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 {2. Chinese Academy of Sciences Beijing 100085 China

Synchrotron-based X-ray techniques have been widely applied to the fields of environmental science due to their element-specific and nondestructive properties and unique spectral and spatial resolution *** techniques are capable of in situ investigating chemical speciation,microstructure and mapping of elements in question at the molecular or nanometer scale,and thus provide direct evidence for reaction mechanisms for various environmental *** this contribution,the applications of three types of the techniques commonly used in the fields of environmental research are reviewed,namely X-ray absorption spectroscopy (XAS),X-ray fluorescence (XRF) spectroscopy and scanning transmission X-ray microscopy (STXM).In particular,the recent advances of the techniques in china are elaborated,and a selection of the applied examples are provided in the field of environmental ***,the perspectives of synchrotron-based X-ray techniques are *** their great progress and wide application,the techniques have revolutionized our understanding of significant geo-and bio-chemical *** is anticipatable that synchrotron-based X-ray techniques will continue to play a significant role in the fields and significant advances will be obtained in decades ahead.

关键词： synchrotron spectroscopy spectromicroscopy environmental science

Chronology of Holocene lacustrine sediments in Co Ngoin, central Tibetan Plateau

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Science china Earth sciences 2006年第9期49卷 991-1001页

作者： WU Yanhong1, WANG Sumin1& HOU Xinhua1,3 1. Key Laboratory of Lake Sedimentation and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of sciences, Nanjing 2.0008, china 2. Institute of Tibetan Plateau {2., Chinese Academy of sciences, beijing 10085, china 3. Graduate University of Chinese Academy of sciences, beijing 100039, china 1. Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China 2. Institute of Tibetan Plateau research Chinese Academy of Sciences Beijing 10085 China 3. Graduate University of Chinese Academy of sciences Beijing 100039 China

Chronology is the basis for using lacustrine sediments to reconstruct the history of en-vironmental change. Radioactive-nuclides such as 14C, 2.0Pb and 137Cs dating are mainly used to establish the chronology for recent several ten thousand years. Because of being mixed with “dead carbon”, the measured 14C age is always older than the actual age which is recognized as “reservoir effect”. Cs is a kind of active metal element, and easy to migrate vertically in the sediment that leads to the error of the time marker. 2.0Pb dating should make sure to select CIC model or CRS model. On the Tibetan Plateau, most of the lakes are alkaline closed lake where Cs is more moveable in the sediment and the reservoir effect caused by “dead carbon” on 14C dating is stronger. Based on the analysis on results of 14C, 2.0Pb and 137Cs of the lacustrine sediments from Co Ngoin, central Tibetan Plateau, we use the simple regression method to re-calculate the 14C calendar ages, and establish the time sequence for cores CE-1 and CE-2.with result of 2.0Pb CRS model for the upper 35 cm and re-calculated 14C calendar age for sediments bellow 35 cm. Since 1400 cal. a BP, sedimentation inter-rupted for more than 1000 years. According to this time sequence, variations of environmental proxies confidently reflect the major climatic events in Holocene.

关键词： 14C, 2.0Pb and 137Cs, chronology, lacustrine sediments, climatic event, Co Ngoin, central Tibetan Plateau.