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Difference schemes on non-uniform mesh and their application

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Progress in Natural Science:Materials International 2004年第10期14卷 8-14页

作者： MA Yanwen ,GAO Hui,FU Dexun and LI Xinliang (Laboratory of Nonlinear Mechanics,institute of Mechanics,chinese academy of {3.,beijing1.0080,China) chinese Acad Sci Inst Mech Lab Nonlinear Mech Beijing 100080 Peoples R China

High order accurate schemes are needed to simulate the multi-scale complex flow fields to get fine structures in simula-tion of the complex flows with large gradient of fluid parameters near the wall,and schemes on non-uniform mesh are desirable for many CFD(computational fluid dynamics)*** construction methods of difference approximations and several difference approxima-tions on non-uniform mesh are *** accuracy of the methods and the influence of stretch ratio of the neighbor mesh increment on accuracy are *** comments on these methods are given,and comparison of the accuracy of the results obtained by schemes based on both non-uniform mesh and coordinate transformation is made,and some numerical examples with non-uniform mesh are present-ed.

关键词： scheme on non-uniform mesh high order accurate scheme compact difference approximation

Synthesis,characterization,and thermostability of bis(2,2,6,6-tetramethyl-3.5-heptanedionato)copper(Ⅱ)

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Rare Metals 2012年第4期31卷 343-349页

作者： ZHANG Teng,GU Hongwei,DING Fazhu,QU Fei,and DAI Shaotao Key Laboratory of Applied Superconductivity,institute of Electrical Engineering,chinese academy of {3.,beijing 100190,China Key Laboratory of Applied Superconductivity Institute of Electrical Engineering Chinese Academy of Sciences Beijing China

Owing to the adaptability to large scale processing,excellent composition control and film uniformity,the metal-organic chemical vapor deposition（MOCVD） technique is a promising process for high-temperature superconductor YBa;Cu;O;（YBCO） *** this technique,the evaporation characteristics and thermostability of adopted precursors in whole process will decide the quality and reproducible results of YBCO *** the present report,bis（2,2,6,6-tetramethyl-3.5-heptanedionato）copper（II）(Cu（TMHD）;) was synthesized by the interaction of copper acetate hydrate with TMHD in methanol solution,and its structure was identified by FTIR,1 H NMR,and EI-MS ***,thermal property and the kinetics of decomposition were systematically investigated by nonisothermal thermogravimetric analysis methods（TGA） at different heating rates in streams of N;,and the average apparent activation energy of evaporation process was evaluated by the Ozawa,Kissinger,and Friedman *** possible conversion function was estimated through the Coats-Redfern method to characterize the evaporation patterns and followed a phase boundary reaction mechanism by the contracting area equation with average activation energy of 85.1 kJ·mol;.

关键词： Cu(TMHD)_2 metal-organic chemical vapor deposition(MOCVD) synthesis thermostability

A NEW PRIMITIVE CHALICOTHERE (PERISSODACTYLA,MAMMALIA) FROM THE EARLY EOCENE OF HUBEI, CHINA

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古脊椎动物学报(中英文） 1995年第2期 150-159页

作者： Wang Yuan(institute ol Vertebrate Poleontology and Paleoanthropology chinese academy of sciences, beijing 100044. China)

A new material of perissodactyl represented by a crushed skull and the same individual’s pair of mandibles (both lost their posterior parts) is described in this paper. The specimen was collected in 1992 by Dr. Wang Yuanqing of IVPP from the late Early Eocene of Danjiangkou, Hubei, China. This new material, Danjiangia pingi gen. et sp. nov., is here referred to Chalicotheribidea and recognized as the earliest known chalicothere. Several relevant issues, such as the early character evolution of chalicothere group, the possible close relationship between chalicothere and palaeothere group and the origin of chalicotheres, will also be tentatively discussed in the present paper.

关键词： Liguanqiao Basin Hubei Early Eocene Chalicothere

Uncertainty analysis of CO_2 flux components in subtropical evergreen coniferous plantation

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Science China Earth sciences 2009年第2期52卷 257-268页

作者： LIU Min1,2,3. HE HongLin1, YU GuiRui1, LUO YiQi4, SUN XiaoMin1 & WANG HuiMin1 1 institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, {3. 100101, China 2 Gradute School of the chinese academy of sciences, {3. 100049, China 3.School of Geography Science, Nanjing Normal University, Nanjing 210097, China 4 Department of Botany and Microbiology, University of Oklahoma, 770 Van Vleet Oval, Norman, OK 73.19, USA 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 2. Gradute School of the chinese academy of sciences Beijing 100049 China 3. School of Geography Science Nanjing Normal University Nanjing 210097 China 4. Department of Botany and Microbiology University of Oklahoma 770 Van Vleet Oval Norman OK 73019 USA

We present an uncertainty analysis of ecological process parameters and CO2 flux components (Reco, NEE and gross ecosystem exchange (GEE)) derived from 3.years’ continuous eddy covariance meas-urements of CO2 fluxes at subtropical evergreen coniferous plantation, Qianyanzhou of ChinaFlux. Daily-differencing approach was used to analyze the random error of CO2 fluxes measurements and bootstrapping method was used to quantify the uncertainties of three CO2 flux components. In addition, we evaluated different models and optimization methods in influencing estimation of key parameters and CO2 flux components. The results show that: (1) Random flux error more closely follows a dou-ble-exponential (Laplace), rather than a normal (Gaussian) distribution. (2) Different optimization meth-ods result in different estimates of model parameters. Uncertainties of parameters estimated by the maximum likelihood estimation (MLE) are lower than those derived from ordinary least square method (OLS). (3. The differences between simulated Reco, NEE and GEE derived from MLE and those derived from OLS are 12.18% (176 g C·m-2·a-1), 3..3.% (79 g C·m-2·a-1) and 5.4% (92 g C·m-2·a-1). However, for a given parameter optimization method, a temperature-dependent model (T_model) and the models derived from a temperature and water-dependent model (TW_model) are 1.3.% (17.8 g C·m-2·a-1), 2.1% (5.7 g C·m-2·a-1), and 0.26% (4.3.g C·m-2·a-1), respectively, which suggested that the optimization methods are more important than the ecological models in influencing uncertainty in estimated carbon fluxes. (4) The relative uncertainty of CO2 flux derived from OLS is higher than that from MLE, and the uncertainty is related to timescale, that is, the larger the timescale, the smaller the uncertainty. The relative uncertainties of Reco, NEE and GEE are 4%-8%, 7%-22% and 2%-4% respectively at annual timescale.

关键词： CO2 flux components statistical uncertainty analysis bootstrapping method subtropical evergreen coniferous plantation Qianyanzhou

present status and development on biological nitrogen fixation research in China

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chinese Science Bulletin 2003年第10期48卷 954-960页

作者： SHEN Shihua & JING Yuxiang Key Laboratory of Photosynthesis and Plant-Environment MolecularPhysiology, institute of Botany, chinese academy of sciences, beijing 100093. China Key Laboratory of Photosynthesis and Plant-Environment Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

This presentation introduces the advances inbiological nitrogen fixation research abroad, in particular,describes the great progress and achievements on itsresearch in China as follows: collection of rhizobial resources and establishment of the largest database of Rhizobium inChina, correction and development of Rhizobium taxonomy in international; discovery of a couple of nif genes,identification and unification of linkage among the nif gene operons of Klebsiella pneumoniae, finding of regulative mechanism of positive regulation nif gene and its sensitivity to oxygen, temperature; finding of the activity of nodulation gene nodD3.product in Sinorhizobium meliloti which is notcontrolled by flavonoid produced from its host alfalfa;finding of the association between expression of genes coding the products for carbon utilization and nitrogen metabolism and their regulations; chemical synthesis of nodulationfactor of Sinorhizobium meliloti; constructions of engineered nitrogen fixers and utilization in practice based on theresearch of gene expression and regulation; chemicalsimulation of the structure and function of nitrogenase and bringing forward the model of nitrogenase active center for the first time in international and synthesis of modelcompounds which were paid attention by colleagues abroad. Finally, the development of nitrogen fixation research inChina in future has been put forward, suggesting that the nifgene regulation and its role in providing crops with nitrogen element, signal transduction and molecular interactions between Rhizobium and legume, coupling between carbonand nitrogen metabolisms, nitrogen fixation andphotosynthesis, and functional genomics of nitrogen-fixing nodule symbiosis, etc., would be actively worked on.

关键词：现状发展生物固氮技术中国固氮酶基因表达微生物植物相互作用化学模型

Magnetocrystalline Anisotropies of RFe_(10)V_2 (R=Y, Tb, Dy, Ho, and Er) and Their Hydrides

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Journal of Materials Science & Technology 1998年第5期14卷 447-450页

作者： Weiren ZHAO Jueyun PING and Ruzhang MA (Material Physics Dept., University of Science and Technology beijing, beijing 100083. China)(present {3.: Central Iron & Steel Research institute,beijing 100081, China) Material Physics Dept. University of Science and Technology Beijing Beijing 100083 China Central Iron and Steel Research institute Beijing 100081 China

The magnetocrystalline anisotropies of RFe10V2 (R=Y, Tb, Dy, Ho and Er) and their hydrides were studied by X-ray diffraction, magnetization and a.c. susceptibility measurements. The uniaxial anisotropy of Fe-sublattice and R-sublattice with positive second order Stevens αJ in RFe10V2 compounds is weakened by hydrogenation, while that of R-sublattice with negative αJ (Er) enhanced. Such a change of anisotropy causes planar-easy magnetic structures in RFe10V2 (R=Tb and Dy) at room temperature and induces spin reorientation in HoFe10V2 after hydrogenation. The change of anisotropy of R-sublattice after hydrogenation may be owed to a decrease of the second order crystalline coefficient.

关键词： Ho and Er and Their Hydrides V2 R=Y Dy Magnetocrystalline Anisotropies of RFe

A NEW MACROPETALICHTHYID FROM CHINA, WITH SPECIAL REFERENCE TO THE HISTORICAL ZOOGEOGRAPHY OF THE MACROPETALICHTHYIDAE (PLACODERMI)

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古脊椎动物学报(中英文） 1996年第4期 264-268页

作者： ZHU Min WANG Junqing(institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of sciences beijing 100044)

It has been recognized that South China is one of important distribuhon areas of theMacropetalichthvidae. Since close reatives of the Macropetalichthyidae were excusively discoveredin the Middle Paleozoic Shata of South China and Ninxia, the Study of earlyInacropetalichthyids from China is key to the reseach on the origin and evolution of theMacropetalichthytdae. In the present paper, a new genus and species of theMacropetalichthyidae, Hmptahchthy longhuaensis, is fortal from the Eariy boonianof tonghua hill, Qujing, Yunnan. The fish-haring bed lies in the top of theXuedong Fonnahon, overlain by the Chuandong Fonnaon- Zhu et al,(1994)sugpethat the age of the Xuiachong Fonnahon was Late Pragian to Eariy Eedan.

关键词： Qujing (Yunnan) Early Devonian Macropetalichthyidae Historical Zoogeography

Some results about holomorphic vector bundles over general Hopf manifolds

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Science China Mathematics 2009年第12期52卷 2863-2866页

作者： ZHOU XiangYu institute of Mathematics,academy of Mathematics and Systems Science,and Hua Loo-Keng Key Laboratory of Mathematics,chinese academy of sciences,beijing 100190,China 1. institute of Mathematics Academy of Mathematics and Systems Science and Hua Loo-Keng Key Laboratory of Mathematics Chinese Academy of Sciences Beijing 100190 China

In the present note that grew out of my talk given at the conference in honor of Prof. Zhong Tongde,I give a survey of some recent results about holomorphic vector bundles over general Hopf manifolds.

关键词： holomorphic vector bundles Hopf manifolds cohomology groups 3.L10 3.L05 3.J18

Numerical study on onset of oscillatory thermocapillary flow in rectangular liquid pool

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Science China(Technological sciences) 2010年第4期53卷 1069-1076页

作者： HU WenRui,TANG ZeMei & LI Kai Key Laboratory of Microgravity(National Microgravity Laboratory),institute of Mechanics,chinese academy of {3.,beijing10090,China 1. Key Laboratory of Microgravity (National Microgravity Laboratory) Institute of Mechanics Chinese Academy of Sciences Beijing 10090 China

Thermocapillary flow in a rectangular liquid pool of large Prandtl fluid(Pr=105.6) is numerically studied in *** thermocapillary flow arises when the imposed temperature difference between the sidewalls exceeds a critical *** fluctuations of the oscillatory flow,accompanied by the propagation of the hydrothermal wave from the cold sidewall to the hot one,are much smaller than the time-averaged velocity and temperature *** corresponding disturbance cells arise in the centre of the liquid pool initially,and extend to the whole region with the increasing imposed temperature *** present study reveals the different characteristics of the oscillatory themocapillary flow in the rectangular liquid pool as compared to the cases in other configurations.

关键词： hydrothermal wave bifurcation numerical simulation microgravity