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Plausible impact of global climate change on water resources in the Tarim River Basin

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Science china Earth sciences 2005年第1期48卷 65-73页

作者： CHEN Yaning & XU Zongxue Xinjiang Institute of Ecology & Geography, Chinese Academy of sciences, Urumqi 830011, china College of environmental sciences, Beijing Normal {4., Beijing 100875, china Xinjiang Institute of Ecology & Geography Chinese Academy of Sciences Urumqi China College of environmental sciences Beijing Normal University Beijing China

Combining the temperature and precipitation data from 77 climatological stations and the climatic and hydrological change data from three headstreams of the Tarim River: Hotan, Yarkant, and Aksu in the study area, the plausible association between climate change and the variability of water resources in the Tarim River Basin in recent years was investigated, the long-term trend of the hydrological time series including temperature, precipitation, and streamflow was detected, and the possible association between the El Ni(n)o/Southern Oscillation (ENSO) and these three kinds of time series was tested. The results obtained in this study show that during the past years, the temperature experienced a significant monotonic increase at the speed of 5%, nearly 1℃ rise; the precipitation showed a significant decrease in the 1970s, and a significant increase in the1980s and 1990s, the average annual precipitation was increased with the magnitude of 6.8 mm per decade. A step change occurred in both temperature and precipitation time series around 1986, which may be influenced by the global climate change. Climate change resulted in the increase of the streamflow at the headwater of the Tarim River, but the anthropogenic activities such as over-depletion of the surface water resulted in the decrease of the streamflow at the lower reaches of the Tarim River. The study result also showed that there is no significant association between the ENSO and the temperature, precipitation and streamflow.

关键词： climate change, hydrological change, temperature, precipitation, streamflow, Tarim River.

Paper sludge as a feasible soil amendment for the immobilization of Pb^(2+)

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Journal of environmental sciences 2010年第3期22卷 413-420页

作者： Xiaojia He, Lei Yao, Zhu Liang, Jinren NiThe Key laboratory of Water and Sediment sciences, Ministry of Education, Department of environmental Engineering, Peking university, Beijing 100871, {4.. The Key laboratory of Water and Sediment sciences Ministry of Education Department of Environmental Engineering Peking University Beijing 100871 China

The possibility of amending Pb 2＋ contaminated soil （S） with paper sludge （P） was investigated through adsorption and desorption experiments. The adsorption process of Pb 2＋ in soil containing paper sludge （SP） could be well described by pseudo second-order kinetic model and the Langmuir isotherm model. After P addition, the equilibrium time decreased greatly （from 28 to 8 hr） and the Pb 2＋ maximum adsorbed amount （Q max ） increased by a factor of more than three to 102.04.mg/g. Q max reached its maximum as S：P was 9：1 （m/m） after 10 days contact between S and P. Moreover, Pb 2＋ adsorbed amount increased with the rise of pH during the adsorption process. Desorption experiments indicated that Pb 2＋ adsorption in SP was irreversible. The metal ion fraction was analyzed with Energy Dispersive Spectrometer and environmental Scan Electron Microscope. As a result, the addition of P to soil was found to induce a decrease in the mobile forms. The Pb 2＋ complexes formation in the presence of carbonates was the main adsorption mechanism. Overall, the paper sludge could be one of the promising soil amendments for the remediation of soil with Pb 2＋ contamination.

关键词： paper sludge pb^2+ adsorption

Electronic structure and magnetism of Fe-doped SiC nanotubes

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1582-1589页

作者： ZHANG WeiHu1,2,3,ZHANG FuChun3,ZHANG ZhiYong4.LU ShuYuan5 & YANG YanNing3 1 Xi’an Institute of Optics and Precision Mechanics,Chinese Academy of sciences,Xi’an 710068,china 2 Graduate university of Chinese Academy of sciences,Beijing 10004.,china 3 College of Physics and Electronic Information,Yan’an university,Yan’an 716000,china 4.Information Science and Technology Institution,Northwest university,Xi’an 710127,china 5 Department of Telecommunications,Xi’an Institute of Posts and Telecommunications,Xi’an 710121,china Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an China Graduate university of Chinese Academy of sciences Beijing China College of Physics and Electronic Information Yan’an University Yan’an China Information Science and Technology Institution Northwest University Xi’an China Department of Telecommunications Xi’an Institute of Posts and Telecommunications Xi’an China

The electronic structure and magnetic properties of Fe-doped SiC nanotubes are investigated by using the first-principles method based on density functional theory(DFT) in the local spin density approximation(LSDA).The calculation results indicate that the SiC nanotube of Fe substitution for C exhibits antiferromagnetism while ferromagnetism features prominently when Fe substitutes *** is a kind of half-metal magnetic *** formation energy calculation results show that the formation energy of ferromagnetic structure is 3.2 eV lower than that of antiferromagnetic *** atoms are more likely to replace Si ***-orbit coupling induces electron spin polarization in the ground ***,the doping Fe atoms make relaxation towards the outside of the tube to some extent and larger geometric distortion occurs when Fe substitutes C,but the whole geometric structure of SiC nanotubes is not damaged due to the *** is revealed in the calculation of energy band structure and density of states that more dispersed distribution of energy levels is produced near the Fermi *** Fe substitution for Si,obviously there are spin-split and intense p-d hybrid effects by Si 3p electron spins and Fe 3d electron spins localized at the exchanging interactions between magnetic transitional metal(TM) *** electronic density results indicate that system magnetic moments are mainly generated by the unpaired 3d electrons of Fe *** these results show that the transition metal doping SiC nanotube could be a potential route to fabricating the promising magnetic materials.

关键词： SiC nanotube the first-principles doped magnetic properties

Global Classical Solutions to Partially Dissipative Quasilinear Hyperbolic Systems

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Chinese Annals of Mathematics,Series B 2011年第5期32卷 771-780页

作者： Yi ZHOU 11 Key laboratory of Mathematics for Nonlinear sciences,Ministry of Education,china Shanghai Key laboratory for Contemporary Applied Mathematics School of Mathematical sciences,Fudan university,Shanghai 2004.3,china. Key laboratory of Mathematics for Nonlinear sciences Ministry of Education China Shanghai Key laboratory for Contemporary Applied Mathematics School of Mathematical sciences Fudan University Shanghai China

The author considers the Cauchy problem for quasilinear inhomogeneous hyperbolic *** the assumption that the system is weakly dissipative,Hanouzet and Natalini established the global existence of smooth solutions for small initial data (in *** ***.,Vol.169,2003,pp.89-117).The aim of this paper is to give a completely different proof of this result with slightly different assumptions.

关键词： Cauchy problem Global classical solution Partially dissipativequasilinear hyperbolic system

Genomics,metagenomics,and microbial oceanography—A sea of opportunities

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Science china Earth sciences 2011年第4期54卷 473-480页

作者： FANG JiaSong 1,2 &ZHANG Li 3 1 State Key laboratory of Marine Geology,Tongji university,Shanghai 200092,china 2 College of Natural and Computational sciences,Hawaii Pacific university,Kaneohe,HI 9674.,USA 3State Key laboratory of Geological Processes and Mineral Resources,Faculty of Earth sciences,china university of Geosciences,wuhan 43.074,china State Key laboratory of Marine Geology Tongji University Shanghai China College of Natural and Computational sciences Hawaii Pacific University Kaneohe USA State Key laboratory of Geological Processes and Mineral Resources Faculty of Earth Sciences China University of Geosciences Wuhan China

Microbial oceanography is an emerging discipline resulted from the interaction,cross-fertilization and integration of life science and ocean *** oceanography integrates the principles of marine microbiology,microbial ecology and oceanography to study the role of microorganisms in the biogeochemical dynamics of natural marine *** application of genomics tools to study marine microbes is resulting in rapid advancements in microbial oceanography that has important implications in global carbon cycle,climate change,and ecosystem *** we review the application of genomics and metagenomics in microbial oceanography and suggest future directions in microbial oceanography research.

关键词： microbial oceanography genomics metagenomics genes biomass bacteria archaea eukarya phylogeny physiology metabolism ecology biogeochemistry microbiology ecosystem function

Effect of biosurfactant on the sorption of phenanthrene onto original and H_2O_2-treated soils

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Journal of environmental sciences 2009年第10期21卷 1378-1385页

作者： PEI Xiaohong, ZHAN Xinhua, ZHOU Lixiang College of Resources and environmental sciences, Nanjing Agricultural university, Nanjing 210095, china. College of Resources and environmental sciences Nanjing Agricultural University Nanjing 210095 China. E-mail: ***@***

The objective of this study was to examine the effect of biosurfactant on the sorption of phenanthrene （PHE） onto the original or HzO2-treated black loamy soil （typic isohumisols） and red sandy soil （typic ferralisols）. The sorption isotherms were performed with the original and ＂soft＂ carbon-removed soils in the presence and absence of biosurfactant （200 mg/L）. The sorption and degradation of biosurfactant were investigated. The result showed that organic matter played an important role in PHE sorption onto the black loamy and red sandy soils, and the PHE sorption isotherms on the ＂soft＂ carbon-removed soils exhibited more nonlinearity than those on the original soils. The values of partition coefficient （Kd） on the original black loamy soil with or without 200 mg/L biosurfactant were 181.6 and 4.4.5 mL/g, respectively. Correspondingly, in the red sandy soil, Kd was 24..4.and 212.8 mL/g in the presence or absence of biosurfactant, respectively. The changes of Kd suggested that biosurfactant inhibited PHE sorption onto the black loamy soil, but facilitated PHE sorption onto the red sandy soil. The nonlinearity of PHE sorption isotherm was decreased in the presence of biosurfactant. Site specific sorption might occur during PHE sorption onto both the original and the ＂soft＂ carbon-removed soils in the presence of biosurfactant. It was noted that biosurfactant could also be sorbed onto soils. The maximal sorption capacity of the red sandy soil for biosurfactant was （76.9 ± 0.007） μg/g, which was 1.31 times that of black loamy soil. Biosurfactant was degraded quickly in the two selected soils, and 92% of biosurfactant were mineralized throughout the incubation experiment for 7 d. It implied that biosurfactant should be added frequently when the remediation of polycyclic aromatic hydrocarbon （PAH）-contaminated soils was conducted through PAH desorption approach facilitated by biosurfactant.

关键词： biosurfactant phenanthrene sorption "soft" carbon soil

Effect of elevated CO_2 on CH_4.emission

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Chinese Science Bulletin 1999年第13期44卷 1153-1157页

作者： WANG DaliState 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 Science Beijing China

Global CH4.emission may increase under CO2 enrichment condition, which is projected for the future. CO2 enrichment could affect CH4.emission in two ways: （ ⅰ ） Photosynthesis of plants that also include plants in r... 详细信息

Global CH4./sub> emission may increase under CO2 enrichment condition, which is projected for the future. CO2 enrichment could affect CH4./sub> emission in two ways: （ ⅰ ） Photosynthesis of plants that also include plants in rice paddies and natural wetlands will be stimulated under CO2 enrichment condition. CH4./sub> emission rate may be increased due to the accumulation of more plant biomass, root exudes and soil organic matters. （ ⅱ ） Combined with other global warming forces, CO2 enrichment may bring a change of atmospheric temperature and precipitation around the world. CH4./sub> emission will also be changed with the variation of the area and distribution of rice paddies and natural wetlands.

关键词： global change CO2 enrichment CH4 emission.

QUALIFICATION OF UNCERTAINTY FOR SIMULATING SOLUTE TRANSPORT IN THE HETEROGENEOUS MEDIA WITH SPARSE GRID COLLOCATION METHOD

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Journal of Hydrodynamics 2009年第6期21卷 779-789页

作者： SHI Liang-sheng YANG Jin-zhong State Key laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China The Sonny Astani Department of Civil and environmental Engineering University of Southern California Los Angeles CA 90089 USA

The sparse grid collocation method is discussed to qualify the uncertainty of solute transport. The Karhunen-Loeve （KL） expansion is employed to decompose the log transformed hydraulic conductivity. The head, velocity and concentration fields are represented by the Lagrange polynomial expansion. A sparse grid collocation method is then used to reduce the original stochastic partial differential equations to a set of deterministic equations which is collocated at selected interpolation （collocation） points. The collocation points are constructed by the Smolyak algorithm. The accuracy, efficiency and convergence property of sparse grid collocation method are investigated by numerical experiments. The analysis shows that stochastic collocation strategy helps to decouple stochastic computations, and all the numerical computation is possible to be implemented by existing deterministic finite element codes. The proposed method provides an efficient way to evaluate the uncertainty of the solute transport in the heterogeneous media.

关键词： stochastic partial differential equations collocation method solute transport uncertainty

Real-time detection of α1A-AR movement stimulated by phenylephrine in single living cells

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Acta Pharmacologica Sinica 2007年第6期28卷 796-802页

作者： Ning XU~(2,5),Zhang-yi LIANG~(3,5),Ming XU~2,Ying-hua GUAN~3,Qi-hua HE~4.Qi-de HAN~2,Xin-sheng ZHAO~(3,6),You-yi ZHANG~(2,6)~2 Institute of Vascular Medicine,Peking university Third Hospital,and Key laboratory of Molecular Cardiovascular sciences,Ministry ofEducation,Beijing 100083,china ~3 Beijing National laboratory for Molecular sciences,State Key laboratory for Structural Chemistry ofUnstable and Stable Species,and Department of Chemical Biology,College of Chemistry and Molecular Engineering,Peking university,Beijing 100871,china ~4.Center of Medical Analysis,Peking university,health Science Center,Beijing 100083,china Institute of Vascular Medicine Peking University Third Hospital and Key Laboratory of Molecular Cardiovascular Sciences Ministry of Education Beijing China Beijing National laboratory for Molecular sciences State Key Laboratory for Structural Chemistry of Unstable and Stable Species Department of Chemical Biology College of Chemistry and Molecular Engineering Peking University Beijing China Center of Medical Analysis Peking University Health Science Center Beijing China

Aim:To investigate the movement of α1A-adrenergic receptors(α1A-AR) stimu-lated by agonist,phenylephrine （PE）,and the dynamics of receptor movement inreal time in single living cells with millisecond ***:We labeledα1A-AR using the monoclonal,anti-FLAG （a kind of tag） antibody and Cy3-conju-gated goat anti-mouse IgG and recorded the trajectory of their transport processin living HEK293A cells stimulated by agonist,PE,and then analyzed their dy-namic ***:The specific detection of α1A-AR on the surface ofliving HEK293A-α1Acells was achieved.α1A-AR internalize under the stimulationof *** the cells were stimulated with PE for 20 min,apparent colocalizationwas found between α1A-AR and *** 4. min stimulation of PE,trajecto-ries of approximate linear motion in HEK293A-α1Acells were recorded,and theirvelocity was ***:The specific labeling method on the livingcell surface provides a convenient means of real-time detection of the behavior ofsurface *** this method we were able to specifically detect α1A-AR andrecord the behavior of individual particles of receptors with 50 ms exposure time inreal time in single living cells.

关键词： adrenergic receptor trajectory living cell