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Diffusion Bonding between TiAl Based Alloys and Steels

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Journal of Materials science & technology 2001年第1期17卷 191-192页

作者： Wenbo HAN and Jiuhai ZHANG National Key Laboratory of Precision Hot Processing of Metals, School of Materials science and Engineering, Harbin institute of technology, Harbin 150001, china Sch. of Mater. Sci. Harbin Inst. of Technol. Harbin 150001 China

The joint of 40Cr steel and TiAl based alloy has been studied by means of a high frequency induction diffusion welder. The experimental results show that, the higher the temperature and pressure, the higher the streng... 详细信息

关键词： temperature and pressure optimum parameters TiAl based alloy high frequency strength of

U-PB ZIRCON AGES OF TIANZHUSHAN GRANITES IN THE EASTERN DABIE OROGEN AND THEIR GEOLOGICAL IMPLICATIONS

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Scientia Geologica Sinica 1998年第4期 521-525页

作者： Ge Ningjie(Department of Earth and space sciences, university of science and technology of china, hefei, {3.)Wu Weiping (Anhui institute of Geological science)Liu Bin (Department of Earth and space sciences, university of science and technology of Chin

The precise U-Ph zircon dating of Tianzhushan granites indicates. the emplacement age of the intrusion is127 Ma. It is one part of the Large-scale magmatic emplacement in the extension environment after thecollision betWeen Yangtze Block (YB) and North china Block (NCB), and is belonged to the granitesformed after collision orogens. This large-scale tectonic magma event not only caused the emplacement ofgranitic intrusion and led to intense metamorphism and deformation of the rocks in Dabie area, but alsoplayed a very important role for the Dabie ultrahigh pressure (UHP) metamorphic rocks ultimatelyreturning to the each surface.

关键词： Pb U-PB ZIRCON AGES OF TIANZHUSHAN GRANITES IN THE EASTERN DABIE OROGEN AND THEIR GEOLOGICAL IMPLICATIONS Wang

QoS-awared replica placement techniques in data grid applications

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science china(Information sciences) 2010年第8期53卷 1487-1496页

作者： XIAO Nong, FU Wei & LU XiCheng School of Computer, National university of Defense technology, Changsha 410073. china School of Computer National University of Defense Technology Changsha China

Quality of service is one of the most important factors for successful grid applications. However, individual QoS constraint (IQC) and QoS-awared replica placement have not yet been well addressed in the existing data grid. Existing QoS-awared replica placement algorithms neither can support multiple QoS attributes, nor have good scalability. In this paper, a three-phrase QoS-awared replica placement algorithm based on matrix, namely TP-GABMAC, is presented to solve these problems. Furthermore, a replica ring mechanism is introduced to maintain replica consistency and manage update conflicting. Experiments and analysis demonstrate that the proposed algorithms are not only stable and scalable, but also work well under different network topologies, access patterns and workloads.

关键词： grid data grid QoS-awared replica placement replica ring

Numerical study of the auroral particle transport in the polar upper atmosphere

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science china(Technological sciences) 2008年第10期51卷 1759-1771页

作者： CAI HongTao1,2, MA ShuYing1,2 & PU ZuYin3.1 School of Electronic Information, Wuhan university, Wuhan 43.079, china 2 Key Laboratory of Geospace Environment and Geodesy, Ministry of Education of PRC, Wuhan 43.079, china 3.School of Earth and Space {3.s, Peking university, Beijing 100871, china School of Electronic Information Wuhan University Wuhan China Key Laboratory of Geospace Environment and Geodesy Ministry of Education of PRC Wuhan China School of Earth and Space sciences Peking University Beijing China

Starting from the Boltzmann equation and with some reasonable assumptions, a one-dimensional transport equation of charged energetic particles is derived by taking account of major interactions with neutral species in the upper atmosphere, including the processes of elastic scattering, the excitation, the ionization and the secondary electron production. The transport equation is numerically solved, for a simplified atmosphere consisting only of nitrogen molecules (N2), to obtain the variations of incident electron fluxes as a function of altitude, energy and pitch angle. The model results can describe fairly the transport characteristics of pre-cipitating auroral electron spectra in the polar upper atmosphere; meanwhile the N2 ionization rates calculated from the modeled differential flux spectra also exhibit good agreements with existing empirical models in terms of several key parameters. Taking the energy flux spectra of precipitating electrons observed by FAST satellite flying over EISCAT site on May 15, 1997 as model inputs, the model-calculated ionization rate profile of neutral atmosphere consists reasonably with that recon-structed from electron density measurements by the radar.

关键词： aurora particle precipitation polar upper atmosphere electron transport equation numerical simulation

THE FLOW PATTERNS OF BUBBLE PLUME IN AN MBBR

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Journal of Hydrodynamics 2011年第4期23卷 510-515页

作者： LI Shi-rong CHENG Wen WANG Meng CHEN Chen Key Laboratory of Northwest Water Resources and Environmental Ecology of Ministry of Education Xi＇an University of Technology Xi＇an 710048 China Oil Production Plant of No. 4 Changqing Oilfield Company China National Petroleum Corporation Jing Bian 718500 China

The flow patterns of the gas-liquid two-phase flow in a Moving-Bed Biofilm Reactor （MBBR） have a critical effect upon the mass transfer by the convection. Bubble plumes promote unsteadily fluctuating two-phase flows during the aeration. This article studies the unsteady structure of bubble plumes through experiments. The time-serial bubble plume images in various cases of the tank are analyzed. The Recursive Cross Correlation-Particle Image Velocimetry （RCC-PIV） is used to calculate the velocities in those cases, and then the time-serial vortex, the total turbulence intensity, the time-serial streamline are obtained. It is shown that the aspect ratio and the void fraction are the dominant factors influencing the unsteady structure of bubble plumes. When the aspect ratio is unity and the void fraction is high, the bubble plumes see a symmetrical vortex structure with a long residence time, which is beneficial for optimizing the aeration system and enhancing the applied range of bubble plumes.

关键词： bubble plume Recursive Cross Correlation (RCC) Particle Image Velocimetry (PIV) flow pattern

Research on the multi-level intake water temperature effect of the Yalong River Jinping-I hydropower project

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science china(Technological sciences) 2011年第S1期54卷 125-132页

作者： WU ShiYong 1,CAO Wei 1,WANG HongMei 1,SUN ShuangKe 2 &CHEN QiuWen 3.1 Ertan Hydropower Development Company,Ltd.,Chengdu 610051,china 2 china Institute of Water Resources and Hydropower Research,Beijing 10003.,china 3.Research {3. for Eco-Environmental sciences,Chinese Academy of sciences,Beijing 100085,china Ertan Hydropower Development Company Ltd. Chengdu China china Institute of Water Resources and Hydropower Research Beijing China Research center for Eco-Environmental sciences Chinese Academy of Sciences Beijing China

Based on the discussion of the multi-level intake application status of high dam reservoir,this paper takes the Jinping-I hydropower project reservoir in the Yalong River as an example,which is shaped by the highest 3.5 m high arch dam,and carries out the forecasting research on the reservoir temperature by numerical simulation and physical model *** paper studies the intake effect of withdrawing the surface warm water by the stoplog gates inlets and verifies the reliability of the mathematical model by comparative *** results show that for a high dam hydropower station,taking the appropriate multi-level intake measure can withdraw the surface warm water in the spawning season and provide a favorable environment for the fish *** technical ideas and implementation scheme are adopted in this *** can provide technical reference for the solutions of similar problems in the future and it also has important engineering significance on the research of water temperature in large deep reservoirs.

关键词： water temperature multi-level intake Jinping-I hydropower project

Simulation on Domain Rotation Path and Magnetostriction of Terfenol-D Alloy

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Journal of Materials science & technology 2001年第4期17卷 473-475页

作者： Jiuchun YAN , Wenbo HAN,Xaoqiu XIE and Shiqin YANG National Key Laboratory of Advanced Welding Production technology, Department of Material science and Engineering, Harbin Institute of technology Harbin 150001, {3. Dept. of Mat. Sci. and Eng. Harbin Inst. of Technol. Harbin 150001 China

Based on a simplified domain rotation model, the rotation path of internal domains and cor- responding magnetostriction of , oriented single Tedenol-D crystals under com- pressive prestresses have been simulated. Comparisons with results of experiment and other calculation have been made. Results of simulation showed that the oriented single crystal has better low-field magnetostriction properties than the oriented one. Under a compressive prestress of 10 MPa, up to 23.0×10-6 saturation magnetostriction of oriented crystal has been obtained at 800 Oe, while for oriented. 1600×10-6 maximum magnetostriction has been reached at 1000 Oe.

关键词： Simulation on Domain Rotation Path and Magnetostriction of Terfenol-D Alloy Path

Dynamic modeling of cellular response to DNA damage based on p53.stress response networks

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Progress in Natural science:Materials International 2009年第10期19卷 1349-1356页

作者： Jinpeng Qi,Yongsheng Ding,Shihuang Shao College of Information sciences and technology,Donghua university,Shanghai 201620,{3. College of Information sciences and technology Donghua University Shanghai 201620 China.

Under acute perturbations from the outside,cells can trigger self-defensive mechanisms to fight against genome *** investigate the cellular response to continuous ion radiation(IR),a dynamic model for p53.stress response networks at the cellular level is *** model can successfully be used to simulate the dynamic processes of double-strand breaks(DSBs) generation and their repair,switch-like ataxia telangiectasia mutated(ATM) activation,oscillations occurring in the p53.MDM2 feedback loop,as well as toxins elimination triggered by p53.stress response ***,the model can predict the plausible outcomes of cellular response under different IR dose regimes.

关键词： p53 DNA damage IR Cellular networks Modelin

Formability of Ti-1023.Alloys Fabricated by Direct Laser Deposition

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稀有金属材料与工程 2011年第S4期40卷 270-273页

作者： Li Huaixue,Gong Shuili,Fei Qunxing,Yu Chengxue science and technology on Beam Power Processes Laboratory,AVIC Beijing Aeronautical Manufacturing technology Research Institute,Beijing 10024,{3. AVIC Beijing Aeronaut Mfg Technol Res Inst Sci & Technol Beam Power Proc Lab Beijing 10024 Peoples R China

Formability of direct laser deposited Ti-1023.alloys was revealed through investigating the pore defects,microstructure and tensile *** results show that gas pores and local non-fusion are two typical defects in the Ti-1023.alloy *** pores are spherical and exist randomly in the deposited ***-fusion defects present irregular and lie in adjacent layer-layer and pass-pass *** layer boundary effects are gradually weakening from the bottom to the top of the single pass *** microstructure of the single pass deposits and multiple pass built block consists of equiaxed ***,the tensile properties of as-deposited Ti-1023.alloys are equal to the as-forged tensile corresponding *** optimizing the laser rapid forming parameters,the non-fusion defects can be eliminated and the dense Ti-1023.parts are obtained.

关键词： Ti-1023 alloys direct laser deposition equiaxed grains epitaxial growth non-fusion