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Flooding 1990s along the Yangtze River, has it concern of global warming?

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Journal of Geographical Sciences 2001年第1期11卷 43-52页

作者： GONG Dao-yi1, ZHU Jin-hong2. WANG Shao-wu2.(1. Key Laboratory of Environmental Change and Natural Disaster, Institute of Resources Science, beijing Normal University, beijing 100875, China 2. {2. of Geophysics, Peking University, beijing 100871, Key Laboratory of Environmental Change and Natural Disaster Institute of Resources Science Beijing Normal University Beijing China department of Geophysics Peking University Beijing China

There were a series of severe floods along the middle to lower reaches of the Yangtze River (Changjiang River) in China during the 1990s. The extensive summer (June, July and August) precipitation is mostly responsible for the flooding. The summer rainfall in the 1980s and the 1990s is much higher than that in the previous 3 decades. The means for 1990–1999 is +87.62.mm above normal, marked the 1990s the wettest decade since the 1950s. Six stations with a time span of 1880–1999 are selected to establish century-long rainfall series. This series also shows that the 1990s is the wettest decade during the last 12. years. In the wettest 12.years, four occurred in the 1990s (1991, 1996, 1998 and 1999). Both global and China’s temperature show there is a relative lower air temperature during the 1960–1970s, and a rapid warming in the 1980–1990s. Comparisons of rainfall between 1960–1979 and 1980–1999 show there are dramatic changes. In the cold period 1960–1979, the summer rainfall along the Yangtze River is 3.8 % to 4.7 % below the normal, during the warm period 1980–1999, over 8.4 % to 18.2.% of summer rainfall occurs. Over the whole eastern China, the summer rainfall shows opposite spatial patterns from the 1960–1970s to 1980–1990s. The consistent trend toward more rainfall with global warming is also presented by the greenhouse scenario modeling. A millennial Drought/flood Index for the middle to lower reaches of the Yangtze River showed that although the surplus summer rainfall in the 1990s is the severest during the past 150 years, it is not outstanding in the context of past millennium. Power spectra of the Drought/flood Index show significant interdecadal periods at 33.3 and 11.8 years. Thus, both the natural interdecadal variations and the global warming may play important roles in the frequent floods witnessed during the last two decades.

关键词： summer rainfall Yangtze River global warming interdecadal variation

Novel ^(99m)Tc labeled σ r eceptor ligand as a potential tumorimaging agent

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Science China chemistry 2006年第2期49卷 169-176页

作者： FAN Caiyun1, JIA Hongmei1, Deuther-Conrad Winnie2. Brust Peter2. Steinbach J?rg2.& LIU Boli1 1. Key Laboratory of Radiopharmaceuticals (beijing Normal University), Ministry of Education, department of {2., beijing Normal University, beijing 100875, China 2. Institute of Interdisciplinary Isotope Research, Permoserstr. 15, 04318 Leipzig, Germany Correspondence should be addressed to Liu Boli 1. Key Laboratory of Radiopharmaceuticals (beijing Normal University) Ministry of Education Department of Chemistry Beijing Normal University Beijing 100875 China 2. Institute of Interdisciplinary Isotope Research Permoserstr. 15 04318 Leipzig Germany

A novel ^(99m)Tc labeled complex,[N-[2.((2.oxo-2.(4-(3-phenylpropyl)piperazin-1-yl)ethyl)(2.mercaptoethyl)amino)acetyl]-2.aminoethanethiolato]Technetium(Ⅴ) oxide (PPPE-MAMA''-^(99m)TcO)([^(99m)Tc]-2. has been designed and prepared based on the integrated approach. The correspondingrhenium complex (PPPE-MAMA''-ReO)(Re-2. has been prepared and characterized. In vitro competitionbinding assays show moderate affinity of Re-2.towards σ_1 and σ_2.receptors with K_i values of8.67 ± 0.07 and 5.71 ± 1.88 μmol, respectively. Planar images obtained at 0.5 h, 4 h, 2. h afteri.v. injection indicate the accumulation of [^(99m)Tc]-2.in MCF-7 human breast tumor bearing mice at2. h. Furthermore, the accumulation of [^(99m)Tc]-2.has been inhibited at 2. h after co-injectionof [^(99m)Tc]-2.plus haloperidol (1 mg/kg). Biodistribution studies of [^(99m)Tc]-2.display an invivo tumor uptake of 0.14% ± 0.01% ID/g at 2. h post i.v. injection with a tumor/muscle ratio of6.02.± 0.87. The above results suggest that [^(99m)Tc]-2. derived from a previously published leadcompound, retains certain tumor uptake and affinity for σ receptors. [^(99m)Tc]-2.may be used as abasis for further structural modifications to develop tumor imaging agents with high affinity for σreceptors.

关键词： tumor σ receptor SPECT ^(99m)Tc

A predict-correct projection method for monotone variant variational inequalities

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Chinese Science Bulletin 1998年第15期43卷 1264-1267页

作者： HAN Qiaoming 1 and HE Bingsheng 2.1. Institute of Applied Mathematics, Chinese Academy of Sciences, beijing 100080, China 2. department of Mathematics, Nanjing University, Nanjing 2.0093, China Institute of Applied Mathematics Chinese Academy of Sciences Beijing China department of Mathematics Nanjing University Nanjing China

A predict_correct projection method is presented for solving monotone variant variational inequalities, which could exploit the advantages and overcome the difficulties of both explicit and implicit projection methods.

关键词： variant variational inequality explicit projection method implicit projection method predict_correct projection method.

Boundedness of solutions and existence of invariant tori for generalized pendulum type equation

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Chinese Science Bulletin 1997年第20期42卷 1673-1675页

作者： HUANG Hai and YUAN Rong1. Institute of Mathematics, Chinese Academy of Sciences, beijing 100080, China 2. department of Mathematics, beijing Normal University, beijing 100875, China Institute of Mathematics Chinese Academy of Sciences Beijing China department of Mathematics Beijing Normal University Beijing China

MOTIVATED by various significant applications to non-Newtonian fluid theory, diffusion offlows in porous media, nonlinear elasticity, and theory of capillary surfaces, several authors(see refs.[1,2. and references cited therein ) have recently studied the existence of periodicsolutions and other properties for the following differential equation:

关键词： boundeduess of solutions invariant tori quasiperlodic solutions Moser’s small twist theorem.

Mathematical stencil and its application in finite difference approximation to the Poisson equation

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Science China Mathematics 2005年第10期48卷 1421-1429页

作者： FENG Hui~1 ZHANG Baolin~(1,2. & LIU Yang~1 1. department of Mathematics,Wuhan University,Wuhan 430072.China 2. Laboratory of Computational Physics,Institute of Applied Physics and Computational Mathematics,beijing 100088. China 1. department of Mathematics Wuhan University 430072 Wuhan China 2. Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics 100088 Beijing China

The concept of mathematical stencil and the strategy of stencil elimination for solving the finite difference equation is presented, and then a new type of the iteration algorithm is established for the Poisson equation. The new algorithm has not only the obvious property of parallelism, but also faster convergence rate than that of the classical Jacobi iteration. Numerical experiments show that the time for the new algorithm is less than that of Jacobi and Gauss-Seidel methods to obtain the same precision, and the computational velocity increases obviously when the new iterative method, instead of Jacobi method, is applied to polish operation in multi-grid method, furthermore, the polynomial acceleration method is still applicable to the new iterative method.

关键词： mathematical stencil, stencil elimination, Poisson equation, finite difference, iterative algorithm,parallelism.

I-V and C-V properties of TiO_2.thin film by pulsed-laser reactive deposition

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Chinese Science Bulletin 1998年第16期43卷 1344-1349页

作者： FU Zhengwen 1, ZHOU Mingfei 1, ZHANG Shengkun 2.CHEN Lianyao 2.and QIN Qizong 1 1. Laser chemistry Institute, Fudan University, Shanghai 2.0433, China 2. department of Physics, Fudan University, Shanghai 2.0433, China Laser chemistry Institute Fudan University Shanghai China department of Pnysics Fudan University Shanghai China

TiO-2.thin films have bee deposited on p-Si(111) substrates by pulsed-laser ablation of metallic Ti target in the O-3 ambient. The current-voltage and capacitance-voltage of the Al/TiO-2.Si capacitors are measured. The results show that the dielectric constant of thin film after being annealed at 700℃ is found to be 46, and the border trap density and the interface state density at the TiO-2.p-Si interface are 1.8×10 12.cm -2.and 2.10 12.eV -1·cm -2. respectively. The conduction mechanisms of as-deposited films are also discussed.

关键词： TiO-2 dielectric properties electrical properties pulsed-laser deposition.

Speciation of the elements and compositions on the surfaces of dust storm particles:The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

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Chinese Science Bulletin 2005年第8期50卷 738-744页

作者： ZHANG Xingying1,2. ZHUANG Guoshun1,2.3, CHEN Jianmin2.& XUE Huaxin2.1. Center for Atmospheric Environment Study, department of chemistry, {2. Normal University, {2. 100875, China 2. Center for Atmospheric chemistry Study, department of Environ- mental Science and Engineering, Fudan University, Shanghai 2.0433, China 3. LAPC/NZC, Institute of Atmospheric Physics, NZC/LAPC, Chinese Academy of Sciences, {2. 10002., China Center for Atmospheric Environment Study Department of Chemistry Beijing Normal University Beijing 100875 China Center for Atmospheric chemistry Study Department of Environmental Science and Engineering Fudan University Shanghai 200433 China LAPC/NZC Institute of Atmospheric Physics NZC/LAPC Chinese Academy of Sciences Beijing 100029 China

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in beijing and Inner Mongolia was studied by XPS. The ma- jor species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2.Al2.3. Sulfate is the dominant species of sulfur on the surface. SiO2.and Al2.3 are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4) produced could account for up to 44.3% and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 2., 2.02. while Fe2.SO4)3, one of the Fe(III) species on the surface decreased from 67.1% to 49.5% and 48.0% respectively. Both S and Fe en- riched on the surface of aerosol particles. Fe(II) accounted for 1.3%?5.3% of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to sup- port the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.

关键词：物种形成原理 XPS 大气悬浮物 Fe-S结合粒子集合

Preparation and characterization of a novel adsorbent for removing lipophilic organic from water

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Science China chemistry 2005年第6期48卷 600-604页

作者： LIU Huijuan1, DAI Ruihua1, QU Jiuhui1 & RU Jia1,2.1. State Key Laboratory of Environmental Aquatic chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, beijing 100085, China 2. Graduate School of the Chinese Academy of Sciences, beijing 100039, China 1. State Key Laboratory of Environmental Aquatic chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences 100085 Beijing China 2. Graduate School of the Chinese Academy of Sciences 100039 Beijing China

A novel composite adsorbent containing a kind of lipid-triolein is studied. The ad-sorbent is prepared by embedding triolein into cellulose acetate (CA) sphere. The preparation method, the physical-chemical properties of the adsorbent and the removal efficiency of two or-ganochlorinated pesticides are studied. The adsorbent is stable in water and no triolein leaks into water for 465 h soaking. The adsorbent has high adsorption capacity for organochlorinated pes-ticides such as dieldrin and aldrin. The results suggest that triolein-containing adsorbent could serve as a good adsorbent for lipophilic organic pollutants. The adsorption rate for lipophilic pol-lutants is very fast and has relation with the logKow of the compounds.

关键词： triolein, cellulose acetate, adsorbent, lipophilic organic, drinking water.

A note on n-edge chromatic number

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Chinese Science Bulletin 1997年第23期42卷 1952-1954页

作者： SUN Liang and ZHANG Zhongfu1. department of Applied Mathematics, beijing Institute of Technology, beijing 100081, China 2. Institute of Applied Mathematics, Lanzhou Institute of Railway, Lanzhou 730070, China department of Applied Mathematics Beijing Institute of Technology Beijing 100081 China

ALL graphs appearing in this note are simple. A graph with p vertices and q edges will becalled a (p, q )-graph. The maximum degree of G is denoted by Δ(G).Let n≥2.be an integer. The n-edge chromatic number X_n (G) of a simple graph G is theminimum cardinality of a set of colors with which one can assign the colors to the edges of Gsuch that the edges on a path of length less than or equal to n receive different *** aim of this note is to explore the bounds for X’_n (G) and X’_n (G) + X’_n (G). It is

关键词： graph complement n-edge chromatic number.