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Theoretical study of aging effects on LaNi_(5) tritium storage

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 676-686页

作者： PING Feilin1,2. JIANG Gang1, ZHANG Lin2.& ZHU Zhenghe1 1. Institute of Atomic and Molecular Physics, Sichuan university, Chengdu 610065, china 2. Research {2. of Laser Fusion, Mianyang 62.900, china 1. Institute of Atomic and Molecular Physics Sichuan University 610065 Chengdu China 2. Research center of Laser Fusion 621900 Miangyang China

The electronic structure and energy of La2.i10H12.and La2.i10H11He (He is at tetrahedral, octahedral or twelve-face polyhedral interstitials) double cells have been calculated using the density functional theory. Their equilibrium structure, energy bands, electronic density of states (DOS) and X-ray diffraction are presented and discussed. The results indicate the helium-3 produced due to the decay of tritium is most possibly sited at twelve-face polyhedral and octahedral interstices and changes the thermodynamic properties of LaNi5 tritide system. The changes due to aging such as the reduction in the isotherm plateau pressure, increase of the isotherm plateau slope, and appearance of deeply trapped hydrogen are caused not only by the lattice expansion, but also by modification of the electronic structure due to the presence of He.

关键词： LaNi5 alloy, density functional theory, electronic structure, aging.

Total coloring of embedded graphs of maximum degree at least ten

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Science china Mathematics 2010年第8期53卷 2127-2133页

作者： HOU JianFeng 1,2.WU JianLiang 2.LIU GuiZhen 2.& LIU Bin 2.1 center for Discrete Mathematics,Fuzhou university,Fuzhou 350002.{2. 2.School of Mathematics,Shandong university,Jinan 2.0100,{2. 1. center for Discrete Mathematics Fuzhou University Fuzhou 350002 China2. School of Mathematics Shandong University Jinan 250100 China

A total k-coloring of a graph G is a coloring of V(G) ∪ E(G) using k colors such that no two adjacent or incident elements receive the same *** total chromatic number χ〃(G) is the smallest integer k such that G has a total *** this paper,it is proved that the total chromatic number of any graph G embedded in a surface Σ of Euler characteristic χ(Σ)≥0 is Δ(G) + 1 if Δ(G)≥10,where Δ(G) denotes the maximum degree of G.

关键词： surface Euler characteristic total coloring total chromatic number

A simple lattice Boltzmann scheme for low Mach number reactive flows

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Science china(Technological Sciences) 2006年第6期49卷 714-726页

作者： CHEN Sheng1,2. LIU Zhaohui2. ZHANG Chao2. HE Zhu2. TIAN Zhiwei2. SHI Baochang 2.& ZHENG Chuguang2.1. Technology center of Wuhan Iron and Steel (Group) Company, Wuhan 430080, china 2. State Key Laboratory of Coal Combustion, Hua Zhong {2. of Science and Technology, Wuhan 430074, china Technology center of Wuhan Iron Steel [Group] Company Wuhan 430080 China State Key Laboratory of Coal Combustion Hua Zhong University of Science Technology Wuhan 430074 China

For simulating low Mach number reactive flows, a simple and coupled lattice Boltzmann (CLB) scheme is proposed, by which the fluid density can bear significant changes. Different from the existing hybrid lattice Boltzmann (HLB) scheme and non-coupled lattice Boltzmann (NCLB) scheme, this scheme is strictly lattice Boltzmann style and the fluid density couples directly with the temperature. Because it has got rid of the constraint of traditional thought in lattice Boltzmann scheme,on the basis of the equality among the particle speed c, the time step △t and the lattice grid spacing △x held, both c and △t can be adjusted in this scheme according to a "characteristic temperature" instead of the local temperature. The whole algorithm becomes more stable and efficient besides inheriting the intrinsically outstanding strong points of conventional lattice Boltz-mann scheme. In this scheme, we also take into account different molecular weights of species, so it is more suitable for simulating actual low Mach number reactive flows than previous work. In this paper, we simulated a so-called "counter-flow" premixed propane-air flame, and the results got by our scheme are much better than that obtained by NCLB. And the more important thing is that the exploration in this work has offered a kind of brand-new train of thought for building other novel lattice Boltzmann scheme in the future.

关键词： lattice Boltzmann, low Mach number flows, reactive flows, simulation.

An integrated decision method for prediction of tropical cyclone movement by using genetic algorithm

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Science china Earth Sciences 2005年第3期48卷 429-440页

作者： YANG Yuanqin1 & WANG Jizhi2.1. National Meteorological center, Beijing 100081,china 2. Chinese Academy of Meteorological Sciences, Beijing 100081,{2. 1. National Meteorological center 100081 Beijing China 2. Chinese Academy of Meteorological Sciences 100081 Beijing China

In this study an integrated decision method for the multi-prediction results of tropical cyclone movements by using genetic algorithm (GA) has been adopted. A genetic learning artifi- cial neural network (GLANN) as a learning mechanism for track prediction was developed through training with the huge samples of typhoon tracks from 1884 to 2.02. The prediction of typhoon motion is to consider how to suit the dynamic change of environment, where typhoon passed through. The neural network structure is described by GA. A fitness function for choice of GA is given to approach the maximum of fitness (the minimum of the errors). Parallel comparing analyses for prediction abilities of unusual typhoon tracks in recent years by GLANN with multi-forecast methods were conducted. More types of cases were employed in the comparing analyses, which consist of the typhoon, Winnie, No.11, in 1997, characterized by a long life over the ocean and in the mainland with severe effect on china, the 10 unusual typhoon tracks in the 1990s, the tracks with landfall and affected action in 1998 and the typhoons born in the Northwestern Pacific and the South china Sea in 2.00, including the 2.—48 h forecast, etc. The results indicated that for prediction ability of typhoon tracks, specially for unusual typhoons, GA decision-making developed in this study is superior to the others.

关键词： genetic algorithm, integrated decision, prediction of tropical cyclone.

Changes of photosynthetic capacity of some plant species under very high CO_2.concentrations in Biosphere 2

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Chinese Science Bulletin 1997年第10期42卷 859-864页

作者： JIANG Gaoming and LIN Guanghui1. Ecological Research center, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, china 2. Biosphere 2.Research and Education center, Columbia university, PO Box 689, Oracle, Arizona 8562., USA Ecological Research center Institute of Botany Chinese Academy of Sciences Beijing 100093 China

THE responses of plant photosynthesis to elevated CO2.could be divided into short-term re-sponse and long-term response or *** the short-term response,photosynthesiscan be enhanced at the beginning of high CO2.treatme... 详细信息

THE responses of plant photosynthesis to elevated CO2./sub> could be divided into short-term re-sponse and long-term response or *** the short-term response,photosynthesiscan be enhanced at the beginning of high CO2./sub> treatment for most C3 carbon fixation species,but the photosynthetic rate may decrease when the plants are exposed to that high CO2./sub> for

关键词： photosynthesis light compensation and saturation points apparent maximum quantum yield of CO2 fixation CO2 Biosphere 2.

First-principle study of interaction of H2.and H2. molecules with （ZnO）_n（n=3-6） ring clusters

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Progress in Natural Science:materials International 2010年第1期20卷 30-37页

作者： Hua-peng CHEN~1,Jian-ning DING~(2.3),Ning-yi YUAN~2.Xiu-qin WANG~2.Cheng-lung CHEN~4,Duan WENG~(1*) 1.Department of materials Science and Engineering,Tsinghua Universtiy,Beijing 100084,china {2. for Low-dimensional materials,Micro-nano Devices and System, Jiangsu Polytechnic university,Changzhou 2.3164,china 3.Key Laboratory of New Energy Source,Changzhou 2.3164,china 4.Department of Chemistry,National Sun Yat-sen university,Kaohsiung 8042.,Taiwan,china [a] Department of materials Science and Engineering Tsinghua Universtiy Beijing 100084 China [b] center for Low-dimensional materials Micro-nano Devices and System Jiangsu Polytechnic University Changzhou 213164 China [c] Key Laboratory of New Energy Source Changzhou 213164 China [d] Department of Chemistry National Sun Yat-sen University Kaohsiung 80424 Taiwan China

A density functional calculation was performed to investigate the impact of hydrogen and water molecules on zinc oxide clusters（ZnO）n=3-6…X,where X=H2.nd *** calculated binding energies were corrected for the basis set superposition error （BSSE）.The structural parameters and chemical hardness were calculated for the complexes of zinc oxide clusters and guest *** strength values of the interaction between the clusters and the guest molecules were analyzed based on the topological properties of atoms in molecules（AIM）theory of *** stereo electronic interactions inside the ZnO clusters were analyzed in detail using the natural bond orbital（NBO）analysis.

关键词： density functional theory zinc oxide clusters atoms in molecules

RESEARCH ON NURBS SKINNING SURFACE VIA COMPLEX CURVES

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Chinese Journal of Aeronautics 1996年第2期9卷 104-110页

作者： Zhang Lenian Zhou Laisui Zhou Rurong (Research center of CAD / CAM Engineering,nanjing {2. of Aeronautics and Astronautics, nanjing, china, 2.0016) Res. center of CAD / CAM Engineering Nanjing Univ. Aero. and Astronaut. Nanjing 210016 China

In order to design the production with complex external shapes, a newmethod is put forward using non-uniform rational B-spline(NURBS)curves to unifythe description of complex curves composed of several segments with different degrees,and then these complex curves are used to construct NURBS skinning surface. Somekinds of skills are used to dispose the knot of NURBS curves and surfaces for practicalproblems. Finally, the method is verified by several complex examples.

关键词： skin (structural member),contours shapes surfaces curves (geometry),elevation

Comparative studies on the structure and adhesion of setae in G. gecko and G. swinhonis

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Science china(Life Sciences) 2007年第6期50卷 831-838页

作者： GUO Ce1, WANG WenBo1, YU Min1, DAI ZhenDong1 & SUN JiuRong2.1 Institute of Bio-inspired Structure and Surface Engineering, nanjing university of Aeronautics and Astronautics, nanjing 2.0016,{2. 2.College of Life Science, Peking university, Beijing 100871,{2. 1. Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China 2. College of Life Science Peking University Beijing 100871 China

Scanning electron microscopy (SEM) and histological techniques were used to observe and study the setae structures of two gecko species (G. gecko and G. swinhonis) and the relationships between these structures and the adhesive forces. The SEM results showed that the setae of these two species were densely distributed in an orderly fashion, and branched with curved tips. The setae of G. gecko had cluster structures, each cluster containing 4-6 setae whose terminal branches curved towards the center of the toes at ~ 10o, the tips of the branches like spatulae and densely arrayed at an interval of less than 0.2.0.3 μm. On the contrary, the branch tips in the setae of G. swinhonis were curled, and the terminal parts of setae curved towards the center of the toes at various angles. Usually the setae of these gecko species branch twice at the top at intervals greater than that of G. gecko. The histological observation found that inside the setae of these two species there were plenty of unevenly distributed contents, such as epithelia, fat cells, pigmental cells and muscle tissue, but no gland cells existed. The results of functional experiments suggested that modifying the structure of gecko’s setae could reduce its adhesive ability dramatically, demonstrating the positive correlation between the structure of the gecko’s setae and its adhesive ability. The above results provide important information in designing bio-mimic setae and bio-gecko robots.

关键词： G. gecko, G. swinhonis, setae, microstructure, adhesion, bionics

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science china Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3 & WANG Huijun2.1. Nansen-Zhu International Research center, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., china 2. Department of Atmospheric Science, Yunnan {2., Kunming 650091, china 3. Graduate {2. of the Chinese Academy of Sciences, Beijing 100049, china 1. Nansen-Zhu International Research center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric Science Yunnan University Kunming 650091 China 3. Graduate university of the Chinese Academy of Sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.