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Re-Os isotopic system and formation age of subcontinental lithosphere mantle

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Chinese science Bulletin 2000年第3期45卷 193-200页

作者： ZHI XiachenDepartment of Earth and Space sciences, university of science and technology of china, hefei 230026, china Advance research center for Earth science and Astronomy, USTC, Third World Academy of science, hefei 230026, china Laboratory of Chemical Geodynamics, USTC, hefei 230026, china Department of Earth and Space sciences University of Science and Technology of China Hefei China Advance research center for Earth science and Astronomy USTC Third World Academy of Science Hefei China Laboratory of Chemical Geodynamics USTC Hefei China

The determination of the formation age of subcontinental Lithosphere Mantle (SCLM) is a widely concerned issue in mantle geochemistry. it is difficult to obtain the formation age of SCLM using lithophile isotopic systems such as Rb-Sr, Sm-Nd, U-Th-Pb, ete., but as siderophile elements, the Re-Os isotopic system provides a powerful tool for that work. Here a comprehensive review on the recent development in Re-Os dating for SCLM has been given.

关键词： Re-Os isotopic dating subcontinental lithospheric mantle mantle derived peridotites Re depleted model age whole rock isochronological age.

research on the reconstruction method of porous media using multiple-point geostatistics

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science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 122-134页

作者： ZHANG Ting 1,2,3, LI DaoLun 1,2 , LU DeTang 1,2 & YANG JiaQing 1,2 1 Department of Modern Mechanics, university of science and technology of china, hefei 23.027, china 2 research center of oil and natural gas, university of science and technology of china, hefei 23.027, china 3 The 28th research Institute, china Electronics technology Group Corporation, Nanjing, 210007, china Department of Modern Mechanics University of Science and Technology of China Hefei China research center of oil and natural gas University of Science and Technology of China Hefei China The 28th research Institute China Electronics Technology Group Corporation Nanjing China

The pore structural characteristics have been the key to the studies on the mechanisms of fluids flow in porous media. With the development of experimental technology, the modern high-resolution equipments are capable of capturing pore structure images with a resolution of microns. But so far only 3D volume data of millimeter-scale rock samples can be obtained losslessly. It is necessary to explore the way of virtually reconstructing larger volume digital samples of porous media with the representative structural characteristics of the pore space. This paper proposes a reconstruction method of porous media using the structural characteristics captured by the data templates of multiple-point geostatistics. In this method, the probability of each structural characteristic of a pore space is acquired first, and then these characteristics are reproduced according to the probabilities to present the real structural characteristics in the reconstructed images. Our experimental results have shown that: (i) the deviation of LBM computed permeability respectively on the virtually reconstructed sandstone and the original sample is less than 1.2%; (ii) the reconstructed sandstone and the original sample have similar structural characteristics demonstrated by the variogram curves.

关键词： porous media reconstruction multiple-point geostatistics pore space training image variogram data template

Relation between Starlight and Nebular Emission Lines of Star-Forming Galaxies

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research in Astronomy and Astrophysics 2005年第3期5卷 221-228页

作者： Hong-Lin Lu, Hong-Yan Zhou, Ting-Gui Wang, Zhen-Quan Zhuang, Xiao-Bo Dong, Jun-Xian Wang and Cheng Li Department for Electronics of science & technology, university of science and technology of china, hefei 230026 center for Astrophysics, university of science and technology of china, hefei 230026 Department for Electronics of science & technology University of Science and Technology of China Hefei 230026 center for Astrophysics University of Science and Technology of China Hefei 230026

We present an exercise that intends to establish a relationship between the strength of nebular emission lines and optical stellar features in the spectrum of a galaxy. After accurately subtracting the stellar continuum and the underlying stellar absorption, we made reliable measurements of the emission lines of all the galaxies in the Sloan Digital Sky Survey Data Release 2 (SDSS DR2). More than 4000 star-forming galaxies with high S/N ratio of both the stellar spectrum and the emission lines are selected. These galaxy spectra are fitted with the 10 PCs of Yip et al., after all the emission line regions have been filtered out. We find that the flux of hydrogen Balmer emission lines, Ha and Hβcan be well recovered from the PCs, while the metal lines are not well reproduced. The fluxes of Ha and Hβmeasured from the PC-reconstructed spectra and from the observed spectra agree well with an rms scatter of only - 0.1 dex. This result suggests that, with moderate spectral resolution and S/N ratio, the optica

关键词： galaxies: fundamental parameters - galaxies: starburst - radiation: lines continuum

Large-Eddy Simulations of turbulent flows with lattice Boltzmann dynamics and dynamical system sub-grid models

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science china(Technological sciences) 2009年第3期52卷 670-679页

作者： GUAN Hui1 & WU ChuiJie2 1 research center for Fluid Dynamics, PLA university of science and technology, Nanjing 211101, china 2 School of Aeronautics and Astronautics, Dalian university of technology, Dalian 116024, china research center for Fluid Dynamics PLA University of Science and Technology Nanjing China School of Aeronautics and Astronautics Dalian University of Technology Dalian China

In this paper, two sub-grid scale (SGS) models are introduced into the Lattice Boltzmann Method (LBM), i.e., the dynamics SGS model and the dynamical system SGS model, and applied to numerically solving three-dimensional high Re turbulent cavity flows. Results are compared with those obtained from the Smagorinsky model and direct numerical simulation for the same cases. It is shown that the method with LBM dynamics SGS model has advantages of fast computation speed, suitable to simulate high Re turbulent flows. In addition, it can capture detailed fine structures of turbulent flow fields. The method with LBM dynamical system SGS model dose not contain any adjustable parameters, and can be used in simulations of various complicated turbulent flows to obtain correct information of sub-grid flow field, such as the backscatter of energy transportation between large and small scales. A new average method of eliminating the inherent unphysical oscillation of LBM is also given in the paper.

关键词： Large-Eddy Simulation Lattice Boltzmann Method dynamics sub-grid scale model dynamical system sub-grid scale model parallel computation

Experimental study on fire smoke movement in a multi-floor and multi-room building

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science china(Technological sciences) 2005年第3期48卷 292-304页

作者： ZHONG Maohua 1, 2 , LI Peide 2 , LIU Tiemin 1 , WEI Xing 1, 2 & LIAO Guangxuan 2 1. National center of Safety science and technology, State Administration of Work Safety, Beijing 100029, china 2. State Key Laboratory of Fire science, university of science and technology of china, hefei 230026, china National center of Safety science and technology State Administration of Work Safety Beijing China State Key Laboratory of Fire science University of Science and Technology of China Hefei China

Fire smoke movement of multi-floor and multi-room (MFMR) fire was studied at the model test building in State Key Laboratory of Fire science (SKLFS). The ingredient, temperature, air pressure difference and air velocity of smoke were measured and analyzed. Meanwhile, the hazard of smoke ingredient to exposed occupants was analyzed based on the national standard, Occupational Exposure Limit for Hazardous Agents in the Workplace (GBZ2-2002). The experimental results showed that the maximum temperature difference in MFMR fire was located along the vertical height from the fire source. With the spreading and diffusion of smoke, the temperature of smoke layer would tend to be no difference. In the fire of woodpile and kerosene, the main smoke ingredients such as SO 2 , CO and CO 2 would first exceed human’s average physiological limit, while smoke ingredients such as NO and NO 2 would come behind. Because of the higher fluctuation range and frequency of air pressure difference of smoke in multi-layer building fire, the fire smoke would spread around everywhere of the passageway and made the human evacuation more difficult.

关键词： multi-floor and multi-room,fire experiment,smoke spread,smoke toxicity.

Distribution,formation and evolution of sand ridges on the East china Sea shelf

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science china(Technological sciences) 2010年第3期53卷 822-828页

作者： ZHAO RenBao 1,2,SUN HaiTao 3,WU YaSheng 3 &ZHAO ChuanFeng 1,2 1MOE Key Laboratory of Petroleum Engineering,china university of Petroleum,Beijing 102249,china 2 Enhanced oil Recovering research center,china university of Petroleum,Beijing 102249,china 3Faculty of natural Resource&Information technology,china university of Petroleum,Beijing 102249,china MOE Key Laboratory of Petroleum Engineering China University of Petroleum Beijing China Enhanced oil Recovering research center China University of Petroleum Beijing China Faculty of natural Resource & Information technology China University of Petroleum Beijing China

Influence of CO2 corrosion on reservoir mineralogical composition,pore structure and their mechanical characteristics was studied using XRD,SEM,rock tri-axial machine and core flow experimental *** was found that the corrosion effect was mainly attributed to rock texture and structure,fluid composition and external dynamical conditions in the experimental *** cores with bedding structures,their bedding surfaces were the preferential corrosion regions,because micro-cracks would evolve at these surfaces in the pressure-releasing ***,for cores with massive structures controlled by stable water environment,the CO2 corrosion would result in pore enlargement and secondary pore *** gas velocity from outlet showed sharp increase in the injection process of CO2-H2O *** could be explained by two changes caused by *** was the opening and closure of *** other was particle *** the corrosion time increased,both tensile strength and compressive strength decreased,which confirmed decrease of cementation *** should also be noted that permeability increase and micro-cracks generation would pose damage to the capacity of CO2 geological storage.

关键词： carbon dioxide geological storage mineralization enhanced oil recovery corrosion

Growth of C_(60)(111) single crystalline thin film on Ni_3Co(111) substrate

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Chinese science Bulletin 1997年第18期42卷 1526-1529页

作者： HOU Jianguo, ZENG Jianlin, WANG Yan, LI Yongqing and WU ZiqinStructure research Laboratory and center for Fundamental Physics, university of science and technology of china, hefei 230026, china Structure research Laboratory anci center for Fundamental Physics University of Science and Technology of China Hefei China

SINCE the discovery of a simple graphite-arc method which can produce grams of C60, the growth of high quality C60 films on various substrates has been one of the main subjects for fullerene research. It is reported that the growth behavior of C60 films is determined by geometrical matching and the bonding properties between C60 lattice and the surface of substrate. Much work has been done to investigate the growth and structure of C60 films on various nonmetallic substrates, such as graphite, MoS2, mica and NaCl. The interactions between C60 and nonmetallic substrates are van der Walls forces, so the growth of C60 on these

关键词： fullerene thin film growth metal substrate.

A method of constructing a database-free optimal dynamical system and a global optimal dynamical system

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science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 905-915页

作者： WU ChuiJie1? & WANG Liang2 1 State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian university of technology, Dalian 116024, china 2 research center for Fluid Dynamics, School of science, PLA university of science and technology, Nanjing 211101, china State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian China research center for Fluid Dynamics School of Science PLA University of Science and Technology Nanjing China

In this paper, to overcome the drawbacks of POT which minimize the reminder, not only the optimal functional with minimal residual is put forward, but also the method of global optimization is used. Under the condition of large reminder, the optimal bases can also be obtained through the method of POTres without the approaching of initial conditions. In addition, compared with local optimization, the advantage of global optimization is remarkable. On the one hand, we can expect that the dynamical system based on the global optimal bases will include more information than the ones based on the local optimal bases, since the global optimal bases are much more precise than the local optimal bases. On the other hand, from the point of view of error, the global optimal bases are independent of the choice of the object functional and the initial bases.

关键词： dynamical system residual global optimization

Energy dispersion of complex non-isolated vortices

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Chinese science Bulletin 2011年第25期56卷 2713-2717页

作者： LUO ZheXian 1,2 1 Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing university of Information science and technology, Nanjing 210044, china 2 Wuxi research center of Environmental science and technology, Wuxi 214031, china Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology Nanjing China Wuxi research center of Environmental science and technology Wuxi China

Energy dispersion is a fundamental scientific problem in the study of natural disasters such as typhoons, heavy rain and earthquakes. The problem has been addressed by both multi-discipline research and forecast studies. The dynamics of isolated circular vortex energy dispersion have been solved. However, the disastrous results of typhoons and heavy rain often occur due to non-isolated circular vortices, the dynamics of which are explored in this paper. The energy dispersion characteristics of non-isolated vortices with complex structural patterns are examined using a linearized nondivergent barotropical vorticity equation model. In the initial field, a tropical cyclone (TC) vortex and a meso-scale vortex coexist, forming a complex structural pattern. An analytic solution based on a Fourier transform and simulations using a two-dimensional model show the following. (1) A wave train of TC-G-D may be created by the energy dispersion where the line connecting the three member centers of the wave train is parallel to the x axis in the case of an initial TC vortex without a meso-scale vortex. (2) A wave train of TC-G-D may also be created by energy dispersion. However, the line connecting the three member centers of the wave train would no longer be parallel to the x axis. Instead, they would form a triangle in the presence of the initial TC vortex with the meso-scale vortex. (3) There is a nonlinear relationship between the initial intensity of the meso-scale vortex and the base angle of the triangle. These results have the potential to be applied in the field of typhoon forecasting.

关键词：能量色散非隔离式旋涡非线性关系中尺度涡台风预报结构模式傅立叶变换