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中国科学院大学学报 1992年第1期 73-83页

作者： Li Bo (institute of geology,Academia Sinica,{2. 10002.)

With an example from the Northern Jiangsu Plain,china,thepaper shows an exception that the peat and soil in a profile arenot always meaning those in situ,but sometimes reworked or even moretransported by *** that point,these kinds of transported andredeposited peat and soil in the past time are hence termed as aeolianpeat and aeolian palaeosols,just like aeolian sand had been termed inthe same *** of bioturbation,lack or obscurity of soil structures,enrichment of wave-/water-generated ripples and wind-drift muddy ororganic draps,and parallelly orientede marks on the surface of organicmatters are the potentially important characteristics of aeolian peat andpalaeosols.

关键词： Holocene Aeolian Peat and Palaeosol

A direct and elementary proof of the stabilization for the wave equation with nonlinear internal damping

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A direct and elementary proof of the stabilization for the w...

Cortactin mediated morphogenic cell movements during zebrafish (Danio rerio) gastrulation

第十九届中国控制会议

作者： Wei-Tao Zhang institute of Systems Science, academy of Mathematics and Systems Science, The {2. academy of sciences, beijing 100080, china.

Using a technique in [4-7] and some integral inequalities due to Haraux and Komornik, one gave a direct and elementaty proof of the stabilization for the wave equation with nonlinear internal damping, extended and uni... 详细信息

关键词： wave equation internal damping stabilization

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Science china(Life sciences) 2005年第6期48卷 601-607页

作者： YU Dan1,2. ZHANG Peijun1 & ZHAN Xi3 1. Experimental Marine Biology Lab, institute of Oceanology, chinese {2. of sciences, Qingdao 2.6071, china 2. Graduate School of the chinese {2. of sciences, beijing 100039, china 3. Greenebaum Cancer Center, Department of Cancer Center, University of Maryland School of Medicine, MD 2.855, USA Experimental Marine Biology Lab Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Graduate School of the chinese academy of {2. Beijing 100039 China Experimental Marine Biology Lab Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China Greenebaum Cancer Center Department of Cancer Center University of Maryland School of Medicine MD 20855 USA

Cell migration is essential to direct embryonic cells to specific sites at which their developmental fates are ultimately determined. However, the mechanism by which cell motility is regulated in embryonic development is largely unknown. Cortactin, a filamentous actin binding protein, is an activator of Arp2.3 complex in the nucleation of actin cytoskeleton at the cell leading edge and acts directly on the machinery of cell motility. To determine whether cortactin and Arp2.3 mediated actin assembly plays a role in the morphogenic cell movements during the early development of zebrafish, we initiated a study of cortactin expression in zebrafish embryos at gastrulating stages when massive cell migrations occur. Western blot analysis using a cortactin specific monoclonal antibody demonstrated that cortactin protein is abundantly present in em-bryos at the most early developmental stages. Immunostaining of whole-mounted embryo showed that cortactin immunoreactivity was associated with the embryonic shield, predominantly at the dorsal side of the embryos during gastrulation. In addition, cortactin was detected in the convergent cells of the epiblast and hypoblast, and later in the central nervous system. Im-munofluorescent staining with cortactin and Arp3 antibodies also revealed that cortactin and Arp2.3 complex colocalized at the periphery and many patches associated with the cell-to-cell junction in motile embryonic cells. Therefore, our data suggest that cortactin and Arp2.3 medi-ated actin polymerization is implicated in the cell movement during gastrulation and perhaps the development of the central neural system as well.

关键词： cortactin, Arp2.3 complex, zebrafish, cell movements, morphogenesis, gastrulation, neurulation.

Texture Evolution of 440 MPa Grade Nb-bearing High Strength IF Steel during Rolling and Annealing Process

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Journal of Wuhan University of Technology(Materials Science) 2011年第6期26卷 1157-1161页

作者：陈银莉 Engineering Research institute University of Science and Technology Beijing

The texture evolution from rolling process to annealing process of 440 MPa grade Nb-bearing high strength IF steel （IF-HSS） was studied. Moreover, the texture of different section in thickness direction of steel sheet after annealing was investigated. Macro-texture measurements using XRD shows that hot rolling texture in Nb-bearing IF-HSS includes a weak γ-fiber and α-fiber, of which main texture components are {001}〈110〉,{111}〈110〉 and {111}〈112.. It is worthy of note that the γ-fiber skeleton line formed after hot rolling. During cold rolling, the absolute maximum shifts to {111}〈112. along the γ-fiber and the maximum along the α-fiber shifts to {112. 〈110〉. During recrystallization annealing process, the weaker α-fiber and stronger γ-fiber cold rolling texture transformed to a very strong γ-fiber annealing texture. After annealing the main components from surface to mid-section along thickness display the same character for both α-fiber and γ-fiber, while textures intensity at 1/4 section is higher than that of surface and mid-section.

关键词： textures recrystallization high strength IF steel

激光烧蚀Al热原子与CF_4反应中C_2.形成及其发光光谱研究

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物理学报 2003年第5期52卷 1297-1301页

作者：张树东李海洋中国科学院安徽光学精密机械研究所环境光谱学实验室

脉冲激光烧蚀金属平面铝靶产生的热原子与气相CF4碰撞反应中 ,在 40 0— 60 0nm之间观测到激发态C2.分子的发光光谱 ,它们可归属为Swan带的d3Πg-a3Πu 跃迁中Δv=2.,1,0 ,- 1,- 2.个振动序列 (v’≤ 6) .光谱强度分析表明 ,C2.激发态... 详细信息

脉冲激光烧蚀金属平面铝靶产生的热原子与气相CF4碰撞反应中 ,在 40 0— 60 0nm之间观测到激发态C2.分子的发光光谱 ,它们可归属为Swan带的d3Πg-a3Πu 跃迁中Δv=2.,1,0 ,- 1,- 2.个振动序列 (v’≤ 6) .光谱强度分析表明 ,C2.激发态的振动温度达 63 40K左右 .与激光烧蚀Al+O2.反应生成AlO的实验结果以及激光烧蚀Cu +CF4的光谱比较 ,对比Al( 2.P1 2.- 2.S1 2.,3 94 4nm)和C2.的d—a跃迁 ( 0— 0 )带带头 ( 5 16 5nm)的飞行时间轮廓 ,认为激发态的Al( 2.S1 2.)原子通过电子态传能可能是C2

关键词：激光烧蚀 C2 CF4 Al 热原子铝靶四氟化碳碰撞反应发光光谱激发态能级跃迁等离子体谱线碳分子

The first-principles study on the doping effect of Re in Ni3Al

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Progress in Natural Science:Materials International 2008年第7期18卷 861-866页

作者： Song Yu a,*, Chongyu Wanga,b, Tao Yua aCentral Iron and Steel Research institute, beijing 100081,{2. bDepartment of Physics, Tsinghua University, beijing 100084,{2. Central Iron and Steel Research institute Beijing 100081 China Department of Physics Tsinghua University Beijing 100084 China

Using first-principles density function for molecules method (DMol) and discrete variational method (DVM) based on the density functional theory, we studied the doping effect of Re in Ni3Al. The structure relaxation and the alloying energy show that Re has a strong Al site preference and leads to the local deformation, which is in agreement with the experimental results and other theoretical results. In addition, the charge density diffierence and the bond order show that Re can strongly enhance the interatomic interaction between the nearest neighbor atoms. From the density of states and the Pauli spectrum, we find that resonance states and localized states are induced by doping Re, and the doped Re atom forms the hybridized bond with the nearest neighbor atoms.

关键词： The first-principles Re Ni3Al

Prediction of Land Use in Liaoning Coastal Economic Zone Based on CLUE-S

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Prediction of Land Use in Liaoning Coastal Economic Zone Bas...

Level Set interface treatment and its application in Euler method

2.10 Second IITA International Conference on Geoscience and Remote Sensing (IITA-GRS 2.10)

作者： Weiling Liu institute of Ecological and Environmental Research chinese Research {2. of Environmental sciences beijing china Linbo Zhang institute of Ecological and Environmental Research chinese Research {2. of Environmental sciences beijing china Jinghai Zhu Liaoning Environment Protection Bureau Shenyang china

Land use and land cover change（LUCC） is an important factor of global environmental *** model is the focus of land change *** of the study area in the next 13 years is predicted based on CLUES *** prediction scenarios were used which are with or without considering "Liaoning Coastal Economy Development Plan".The results showed that the construction land increased dramatically from 1988 to 2.07 due to the economic,population growth and urbanization speed up,while farm,water and forest land decreased *** the same time,Landscape fragmentation in the study area accompanied these *** change trends under the two prediction scenarios plan are *** construction land expanded and farm land decreased more dramatically under the planning *** regional development model is not sustainable.

关键词： Land use and land cover change(LUCC) CLUE-S Liaoning coastal economic zone

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Science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 227-236页

作者： WU KaiTeng1,2.HAO Li3,WANG Cheng4 & ZHANG Li1,2.1 Numerical Simulation Sichuan Higher School Key Laboratory,Neijiang Normal University,Neijiang 641112.china 2.College of Mathematics and Information Science,Neijiang Normal University,Neijiang 641112.china 3 College of Science,{2. University of Civil Engineering and Architecture,{2. 100044,china 4 State Key Laboratory of Explosion Science and Technology,{2. institute of Technology,{2. 100081,china Neijiang Normal University Numerical Simulation Sichuan Higher School Key Laboratory Neijiang China (GRID:grid.464376.4) (ISNI:***) Neijiang Normal University College of Mathematics and Information Science Neijiang China (GRID:grid.464376.4) (ISNI:***) beijing University of Civil Engineering and Architecture College of Science Beijing China (GRID:grid.411629.9) (ISNI:***) beijing institute of Technology State Key Laboratory of Explosion Science and Technology Beijing China (GRID:grid.43555.32) (ISNI:***)

Level Set interface treatment method is introduced into Euler method,which is employed for interface treatment method for multi-materials. Combined with the ghost fluid method,the moving interface is tracked. Fifth-order WENO spatial discretization and third-order TVD Runge-Kutta time discretization methods are used. Shock-wave action on bubble,implosion and velocity field Shock effect bubbles; implosion and velocity field are simulated by means of LS-MMIC3D programmed by C++. Nu-merical results show that the Level Set interface treatment method is effective and feasible for multi-material interface treatment in comparison with the WENO method.

关键词： Euler method Level Set method shock-wave action on bubble implosion numerical simulation

The Compatibility of Polycarboxylate-Type Superplasticizers with Cement

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Journal of Wuhan University of Technology(Materials Science) 2005年第3期20卷 95-98页

作者：李崇智 Department of Civil Engineering Beijing Institute of Civil Engineering and Architecture

Four polycarboxylate- type （ PC ） superplasticizers of different functional groups were used ; their dispersing and retaining behaviors were analyzed through ZETA potential measurement, mini-slump test of cement paste and performance test of concrete. The experimental results show that the dispersing and flow-retaining ability of PC was determined by two factors of anionic groups and nonionic groups ： the density of anionic groups - COO^- or - SO3^- acted on the electronic repulsive force. and the length and proportion of nonionic graft groups of PEO in PC chemical stracture affected the steric effect. The compatibility between PC superplasticizers and cement mainly depended on the type of PEO groups ; furtlwrmore, adding mineral powders is good to the compatibility for high performance concretes （ HPCs ）.

关键词： PC superplasticizers cement compatibility