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Numerical simulation on electromagnetic field,flow field and temperature field in semisolid slurry preparation by A-EMS

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Rare Metals 2010年第6期29卷 635-641页

作者： ZHANG Zhifeng,CHEN Xingrun,XU Jun,and SHI Likai National Engineering & Technology research center for Nonferrous Metal Matrix Composites,General research Institute for Nonferrous Metals,beijing 100088,china National Engineering & Technology research center for Nonferrous Metal Matrix Composites General Research Institute for Nonferrous Metals Beijing China

A two-dimensional computational model coupling an annular electromagnetic stirring（A-EMS） with a macroscopic heat and fluid flow analysis in Al-alloys semisolid slurry preparation was *** dynamic evolutions of the electromagnetic field,flow field,and temperature field were presented successfully by commercial software ANSYS 10.0 with corresponding experimental verification.A horizontally rotational electromagnetic field and,thereby,a more intensive velocity field were uniformly distributed in the stirred melt even at commercial frequency,and thus,a lower temperature difference in the stirred melt and subsequent uniformly fine microstructures were obtained compared with the normal electromagnetic *** simulation results were in good agreement with experimental ones.

关键词： metal forming electromagnetic stirring numerical analysis semisolid slurry

Nonlinear Doob-Meyer Decomposition for General Filtration

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Acta Mathematicae Applicatae Sinica 2002年第4期18卷 619-624页

作者： Qing-quan Linchina Financial Policy research center, School of Finace, Renmin University of china, beijing 100872. china china Financial Policy research center School of Finace Renmin University of China Beijing China

The comparison theorem for generalized backward stochastic differential equations is discussed. Some topics related to equations of this type are also investigated.

关键词： Generalized backward stochastic differential equation Doob-Meyer decomposition theorem,g-supermartingale g-supersolution

Scheduling of Development Projects with Uncertain Iterations

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Journal of Systems Engineering and Electronics 2001年第2期12卷 82-86页

作者： Yan Jihong & Wu Cheng National CIMS Engineering research center, Tsinghua University, beijing 100084, P R. china National CIMS Engineering research center Tsinghua University Beijing 100084 P. R. China

This paper studies the scheduling of design projects in concurrent development process with uncertain number of feedback revisions. An optimization based methodology that combines heuristic algorithm, artificial intelligence (fuzzy, genetic algorithm) and scheduling theory is developed. In the algorithm, weighting values of some key factors are defined by genetic algorithm. In addition, fuzzy logic is used to decide the ability coefficients of different roles taken by designers. Moreover, the process of pre-release and feedback revision is realized. Simulation example is a fraction of practical development project, and satisfied results are obtained.

关键词： Concurrent engineering Product development process Optimization scheduling.

Quantitative studies of hydrocarbon loss of the Silurian bitumen sandstone in the Tarim Basin

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Science china Earth Sciences 2008年第S2期51卷 101-107页

作者： JIANG ZhenXue1,2,PANG XiongQi1,2,LIU LuoFu1,2,WANG XianDong3,ZHANG Jun4 & LI HongYi1,2 1 Basin and Reservoir research center,china University of Petroleum,beijing 102249,china 2 State Key Laboratory of Petroleum Resource and Prospecting,china University of Petroleum,beijing 102249,china 3 research Institute of Exploration and Development,Daqing Oilfield Company Ltd,Daqing 163712,china 4 Petroleum Exploration and Production Institute of SINOPEC,beijing 100083,china Basin and Reservoir research center China University of Petroleum Beijing China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing China research Institute of Exploration and Development Daqing Oilfield Company Ltd Daqing China Petroleum Exploration and Production Institute of SINOPEC Beijing China

The evolution of Tarim Basin experienced several tectonic movements,of which Caledonian movement caused a serious damage to reservoirs of Silurian. The earlier reservoirs size and the later hydrocarbon loss are two key factors to exploration prospect of Silurian. On the basis of net thickness of bituminous sandstone and recovery coefficient of crude oil converting to bitumen,the scale of the hydrocarbon loss of palaeo-accumulation in bitumen sandstone of Silurian was calculated (86.30×108t). The deter-mination of net thickness of bitumen sandstone was completed mainly by several methods,such as physical property demarcation,observing lithology,grains with oil inclusion (GOI) technology,and quantitative grains fluorescence (QGF) technology. The samples of black sandstone and white sand-stone were collected and compared by means of the methods mentioned above. The results showed that there was little hydrocarbon,or none,in the white sandstone. The recovery coefficient was ob-tained by the analyses of plentiful physical parameters of crude oil and bitumen sandstone,based on the hypothesis that nonhydrocarbon compounds and bitumen were invariable in the process of bitu-men forming. The calculated result,which is more scientific and actual,indicates the exploration pros-pect is more promising in Silurian of the Tarim Basin.

关键词： Tarim Basin Silurian bitumen sandstone hydrocarbon loss quantitative research recovery coefficient

Sea water intrusion in coastal areas of Yellow Seaand Bohai Sea

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Journal of Environmental Sciences 1995年第3期7卷 374-384页

作者： Sheng Xuebin Sun Jianzhong Dai Zhaohua(research center for Eco - Environmental Seiences, The ChineseAcademy of Sciences, beijing 100085, china)

ＳｅａｗａｔｅｒｉｎｔｒｕｓｉｏｎｉｎｃｏａｓｔａｌａｒｅａｓｏｆＹｅｌｌｏｗＳｅａａｎｄＢｏｈａｉＳｅａＳｈｅｎｇＸｕｅｂｉｎ；ＳｕｎＪｉａｎｚｈｏｎｇ；ＤａｉＺｈａｏｈｕａ（ＲｅｓｅａｒｃｈＣｅｎｔｅｒｆｏｒＥｃ... 详细信息

ＳｅａｗａｔｅｒｉｎｔｒｕｓｉｏｎｉｎｃｏａｓｔａｌａｒｅａｓｏｆＹｅｌｌｏｗＳｅａａｎｄＢｏｈａｉＳｅａＳｈｅｎｇＸｕｅｂｉｎ；ＳｕｎＪｉａｎｚｈｏｎｇ；ＤａｉＺｈａｏｈｕａ（ＲｅｓｅａｒｃｈＣｅｎｔｅｒｆｏｒＥｃｏ－ＥｎｖｉｒｏｎｍｅｎｔａｌＳｅ...

关键词： sea water intrusion coast ecological agriculture.

Application and Comparison of SST Model in Numerical Simulation of the Axial Compressors

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Journal of Thermal Science 2010年第4期19卷 300-309页

作者： YIN Song~1,JIN Donghai~2,GUI Xingmin~3 and ZHU Fang Aero-Engines Simulation research center,School of Jet Propulsion,beijing University of Aeronautics and Astronautics, beijing,100191,china Aero-Engines Simulation research center School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing China

The shear-stress transport(SST)turbulence model is incorporated into Navier-Stokes equations to simulate a turbomachinery flowfield.A staggered finite volume method is used to make the mean flow equations and turbulence model equations strongly coupled and enhance the stability of the numerical *** implicit treatment of the source terms is applied to the SST model.A steady state solution is obtained using five-stage Runge-Kutta time-stepping scheme with local time stepping and residual smoothing to accelerate convergence. The wall distance d,a key parameter in the SST model,is solved by a partial differential *** validations of the code are conducted on rotor 37,wp11 at design and off-design conditions by comparison with measurements and the Spalart-Allmaras(SA)turbulence *** flow within the tip is calculated with a multi-block grid.

关键词： SST model staggered finite volume method turbomachinery simulation multi-block grid

Three-dimensional decomposition method of global atmospheric circulation

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Science china Earth Sciences 2008年第3期51卷 386-402页

作者： LIU HaiTao1,2,3, HU ShuJuan4, XU Ming5 & CHOU JiFan6,7 1 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, china 2 Graduate University of Chinese Academy of Sciences, beijing 100049, china 3 beijing Climate center, beijing 100089, china 4 Department of Mathematics, Lanzhou University, Lanzhou 730000, china 5 Shanghai Typhoon Institute, Shanghai 200030, china 6 Department of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, china 7 china Meteorological Administration Training center, beijing 100089, china State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China beijing Climate center Beijing China Department of Mathematics Lanzhou University Lanzhou China Shanghai Typhoon Institute Shanghai China Department of Atmospheric Sciences Lanzhou University Lanzhou China china Meteorological Administration Training center Beijing China

By adopting the idea of three-dimensional Walker, Hadley and Rossby stream functions, the global atmospheric circulation can be considered as the sum of three stream functions from a global perspective. Therefore, a m... 详细信息

关键词： three-dimensional decomposition of the global atmospheric circulation generalized Walker Hadley and Rossby stream functions existence and uniqueness vertical motion

Mesozoic subduction-accretion zone in northeastern South china Sea inferred from geophysical interpretations

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Science china Earth Sciences 2006年第5期49卷 471-482页

作者： ZHOU Di1, WANG Wanyin2, WANG Jialin3, PANG Xiong4, CAI Dongsheng5 & SUN Zhen1 1. Key Laboratory of Marginal Sea Geology, South china Sea Institute of Oceanology, Chinese Academy of Sciences, Guang- zhou 510301, china 2. College of Geological and Topographical Engineering, Chang’an University, Xi’an 710054, china 3. Key Laboratory of Marine Geology, Tongji University, Shanghai 200092, china 4. china National Offshore Oil Co. Limited – Shenzhen Branch, Shenzhen 518067, china 5. china National Offshore Oil Co. Limited – research center, beijing 100027, china Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China College of Geological and Topographical Engineering Chang’an University Xi’an China Key Laboratory of Marine Geology Tongji University Shanghai China china National Offshore Oil Co. Limited — Shenzhen Branch Shenzhen China china National Offshore Oil Co. Limited — research center Beijing China

A segment of Mesozoic subduction-accretion zone was inferred across thenortheastern South china Sea at approximately NE450 orientation. Basic evidence includes thefollowing: A belt of peek gross horizontal Bouguer gravity gradient (PGHGBA) is comparable in sizeand intensity to that of the Manila subduction-accretion zone. A belt of high positive magneticanomalies appears to the north and sub-parallel to the PGHGBA, representing the volcanic arcassociated to the subduction zone. The PGHGBA crosses obliquely both Cenozoic structures and presentseafloor topography, indicating a pre-Cenozoic age. The segment is offset left-laterally byNW-running strike-slip faults, in concord with the Mesozoic stress field of South china. Inaddition, the existence of the subduction zone is supported by wide-angle seismic data obtained indifferent years by different institutions. At approximate localities, a north-dipping ramp of Mohosurface is indicated by records of ocean-bottom seismometers, and a strong reflector about 8 kmbeneath the Moho reflector is indicated by both OBS and long-cable seismic records. Theidentification of a segment of Mesozoic subduction zone in NE South china Sea fills nicely the gapof the Great Late Mesozoic Circum SE Asia Subduction-acrretion Zone, which extended from Sumatra,Java, SE Kalimantan to N Palawan, and from Taiwan, Ryukyu to SW Japan.

关键词： Mesozoic, subduction zone, SE Asia, NE South china Sea, geophysics.

Cardioprotective effects of ghrelin and des-octanoyl ghrelin on myocardial injury induced by isoproterenol in rats

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Acta Pharmacologica Sinica 2006年第5期27卷 527-535页

作者： LLian LI~2 Li-ke ZHANG~5 Yong-zheng PANG~(2.4) Chun-shui PAN~(3.4) Yong-fen QI~(3.4) Li CHEN~4 Xian WANG~(3,4) Chao-shu TANG~(3,4) Jing ZHANG~(2,4,6) ~2Institute of Cardiovascular research,Peking University First Hospital,beijing 100034,china:~3Department of Physiology and Pathophysiology,Peking University Health Science center,beijing 100083,china ~4Key Laboratory of the Ministry of Education on Molecular Cardiology,beijing 100083,china:~5Department of Pathophysiology,Capital University of Medicine,beijing 100054,china Institute of Cardiovascular research Peking University First Hospital Beijing China Department of Pathophysiology Capital University of Medicine Beijing China Key Laboratory of the Ministry of Education on Molecular Cardiology Beijing China Department of Physiology and Pathophysiology Peking University Health Science Center Beijing China

Aim:To determine the cardioprotective action of ghrelin and des-octanoyl ghrelinin rats with isoproterenol-induced myocardial ***:Rats were subcu-taneously injected with isoproterenol （ISO;20,10,and 5 mg/kg） on d 1,2 and 3,respectively,and then 3 mg/kg for the next 7d with or without ghrelin or des-octanoyl-ghrelin （100μg/kg,twice daily）.Plasma ghrelin and growth hormonelevels were assayed using radioimmunoassay *** hormone secreta-gogue receptor （GHSR） and ghrelin mRNA were determined using *** binding capacity and the affinity for [3H]ghrelin were determined by re-ceptor binding ***:Compared with controls,ISO-treated rats showedsevere myocardial injury,cardiomegaly,infarction-like necrosis and massive fi-brosis with increases in irradiated-ghrelin （ir-ghrelin） content in plasma by 67%and myocardia by 66% and in the mRNA level in the myocardia by 93% （P<0.01）.ISO-treated rats had 95% （P<0.01） higher GHSR mRNA levels in the *** maximal binding capacity of [3H]ghrelin for myocardial sarcolemma was higherin ISO-treated rats than in *** administration improved cardiac func-tion and ameliorated cardiomegaly and attenuated myocardial lipid peroxidationinjury and relieved cardiac fibrosis as compared with ISO treatment ***-istration of des-octanoyl ghrelin effectively antagonized ISO-induced myocardialinjury and improved all parameters ***,the therapeutic effect ofdes-octanoyl ghrelin was significantly weaker than that of *** plasmagrowth hormone level increased markedly,by 1.5-fold （P<0.01）,with ghrelinadministration as compared with that in controls,but was unaltered in the des-octanoyl ghrelin ***:Myocardial ghrelin and GHSR were up-regulated during ISO-induced myocardial *** protective effect of ghrelinagainst ISO-induced cardiac function injury and fibrosis was more potent thanthat of des-octanoyl ghrelin,which suggests that ghrelin could be an endog

关键词： ghrelin des-octanoyl ghrelin myocardium fibrosis isoproterenol