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Science china(Technological Sciences) 2009年第9期52卷 2502-2509页

作者： WANG YanHui Research institute of Architecture,Southeast University,Nanjing 210096,china Research institute of Architecture Southeast University Nanjing China

The protective remolding and reusing of industrial historic buildings and sites is regarded as a great scientific matter in today's urban development. Based on discussing its significance and value,this paper,taking a specific example,makes a systematic discussion on the design strategy and method from the aspects of overall planning,remolding the old buildings,designing the new buildings,etc.

关键词： industrial historic buildings and sites protective remolding and reusing renascence strategy

Multi-scale calculation of settling speed of coarse particles by accelerated Stokesian dynamics without adjustable parameter

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Acta Mechanica Sinica 2009年第3期25卷 303-310页

作者： Long Wang Jiachun Li Jifu Zhou institute of Mechanics, CAS, 100190 Beijing, china institute of Mechanics CAS Beijing China

The calculation of settling speed of coarse particles is firstly addressed, with accelerated Stokesian dynamics without adjustable parameters, in which far field force acting on the particle instead of particle velocity is chosen as dependent variables to consider inter-particle hydrodynamic interactions. The sedimentation of a simple cubic array of spherical particles is simulated and compared to the results available to verify and validate the numerical code and computational scheme. The improved method keeps the same computational cost of the order O（NlogN） as usual accelerated Stokesian dynamics does. Then, more realistic random suspension sedimentation is investigated with the help of Mont Carlo method. The computational results agree well with experimental fitting. Finally, the sedimentation of finer cohesive particle, which is often observed in estuary environment, is presented as a further application in coastal engineering.

关键词： Sedimentation Stokesian dynamics Many-body interactions Multi-scale

ORDER PROPERTIES AND CONSTRUCTION OF SYMPLECTIC RUNGE-KUTTA METHODS

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Journal of Computational Mathematics 2000年第6期18卷 645-656页

作者： Shou-fu Li (institute for Computational and Applied Mathematics, Xiangtan University, Xiangtan 411105, china) 湘潭大学湖南湘潭 411105

The main results of this paper are as follows: (1) Suppose an s stage Runge-Kutta method is consistent, irreducible, non-confluent and symplectic. Then this method is of order at least 2p + l(1 less than or equal to p less than or equal to s - 1) provided that the simplifying conditions C(p) (or D(p) with non-zero weights) and B(2p + l) hold, where 1 0, 1, 2. (2) Suppose an s stage Runge-Kutta method is consistent, irreducible and non-confluent, and satisfies the simplifying conditions C(p) and D(p) with 0 s. Then this method is symplectic if and only if either p = s or the nonlinear stability matrix M of the method has an (s - p) x (s - p) chief submatrix (M) over cap = 0. (3) Using the results (1) and (2) as bases, we present a general approach for the construction of symplectic Runge-Kutta methods, and a software has been designed, by means of which, the coefficients of s stage symplectic Runge-Kutta methods satisfying C(p),D(p) and B(2p + l) can be easily computed, where 1 I P less than or equal to s, 0 less than or equal to l less than or equal to 2, s less than or equal to 2p + l less than or equal to 2s.

关键词： numerical analysis symplectic Runge-Kutta methods simplifying conditions order results

δD values of escaped H_2 from hot springs at the Tengchong Rehai geothermal area and its origin

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Chinese Science Bulletin 2002年第2期47卷 146-149页

作者： SHANGGUAN Zhiguan & HUO Weiguo institute of Geology, china Seismological Bureau, Beijing 100029, china institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, china institute of Geology China Seismological Bureau Beijing 100029 China

Here we give the δD values of escaped H2 from hot springs at the Tengchong Rehai and adjacent regions, and deal with a genetic correlation between the increment H2 in escaped gases from middle-shallow reservoirs and the H2S, CH4 derived from deep sources. Isotopic compositions of H2 indicate that the generation of increment H2 may be related to recent strong activity of N-W trending fault at the Rehai area. Trace monitoring the H2 release could be significant in order to keep watch on present activity of that fault.

关键词： Rehai geothermal area hydrogen stable isotopic composition.

Fluorescence Associated with Impurities in Nanostructured Al_2O_3

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Journal of Materials Science & Technology 1996年第1期12卷 19-24页

作者： Lide ZHANGt and GuoZhong WANG(institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, china)Chimei MO(Dept. of Materials Science and Engineering, University of Science and Technology of china, Hefei 230026, china)Tienan ZHAO(institute institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China Dept. of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China institute of Physics Chinese Academy of Sciences Beijing 100080 China

The fluorescent spectra of nanostructured Al2O3 after heat-treating at different temperatureshave been systematically investigated. The results show that for η-Al2O3 and γ-Al2O3, two broadfluorescent bands P1 and P2 appear in the wavenumber range of 20000 cm-1 to 11500 cm-1,and P1 and P2 bands are located in the wavenumber range of 20000 cm-1 to 14500 cm-1 and14500 cm-1 to 11500 cm-1, respectively The P1 band can be attributed to the impurity Cr3+luminescence. This is consistent with other author's result for the Cr doped Al2O3. The P2band is a new fluorescent phenomenon, which has not been reported previously. In this paper,the condition of the appearance of P2 and its mechanism is discussed in detail.

关键词： Al Cr der OO Fluorescence Associated with Impurities in Nanostructured Al2O3

On the fundamental equation of nonequilibrium statistical physics—Nonequilibrium entropy evolution equation and the formula for entropy production rate

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Science china(Physics,Mechanics & Astronomy) 2010年第12期53卷 2194-2215页

作者： XING XiuSan Department of Physics, Beijing institute of Technology, Beijing 100081, china Department of Physics Beijing Institute of Technology Beijing China

In this paper the author presents an overview on his own research works. More than ten years ago, we proposed a new fundamental equation of nonequilibrium statistical physics in place of the present Liouville equation. That is the stochastic velocity type’s Langevin equation in 6N dimensional phase space or its equivalent Liouville diffusion equation. This equation is time-reversed asymmetrical. It shows that the form of motion of particles in statistical thermodynamic systems has the drift-diffusion duality, and the law of motion of statistical thermodynamics is expressed by a superposition of both the law of dynamics and the stochastic velocity and possesses both determinism and probability. Hence it is different from the law of motion of particles in dynamical systems. The stochastic diffusion motion of the particles is the microscopic origin of macroscopic irreversibility. Starting from this fundamental equation the BBGKY diffusion equation hierarchy, the Boltzmann collision diffusion equation, the hydrodynamic equations such as the mass drift-diffusion equation, the Navier-Stokes equation and the thermal conductivity equation have been derived and presented here. What is more important, we first constructed a nonlinear evolution equation of nonequilibrium entropy density in 6N, 6 and 3 dimensional phase space, predicted the existence of entropy diffusion. This entropy evolution equation plays a leading role in nonequilibrium entropy theory, it reveals that the time rate of change of nonequilibrium entropy density originates together from its drift, diffusion and production in space. From this evolution equation, we presented a formula for entropy production rate (i.e. the law of entropy increase) in 6N and 6 dimensional phase space, proved that internal attractive force in nonequilibrium system can result in entropy decrease while internal repulsive force leads to another entropy increase, and derived a common expression for this entropy decrease rate or anothe

关键词： stochastic velocity type’s Langevin equation in 6N dimensional phase space drift-diffusion duality nonequilibrium entropy evolution equation entropy diffusion formula for entropy production rate entropy change from internal interaction a

N DIMENSIONAL FINITE WAVELET FILTERS

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Journal of Computational Mathematics 2003年第5期21卷 595-602页

作者： Si-long Peng (NADEC, institute of Automation, Chinese Academy of Sciences, Beijing 100080, china) NADEC Institute of Automation Chinese Academy of Sciences 北京 100080

In this paper, a large class of n dimensional orthogonal and biorthognal wavelet filters (lowpass and highpass) are presented in explicit expression. We also characterize orthogonal filters with linear phase in this c... 详细信息

关键词： n Dimension Linear phase Wavelet filters.

BIVARIATE RATIONAL IN TERPOLANTS WITHRECTANGLE-HOLE-STRUCTURE

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Journal of Computational Mathematics 1999年第1期17卷 1-14页

作者： Jie-qing Tan(institute of Applied Mathematics, Hefei University Of Technology, Hefei 230009, china) 合肥工业大学应用数学系安徽合肥

Bivariate vector valued rational interpolants are established by means of Thiele-type branched continued fractions and Samelson inverse over rectangular grids with holes, characterisation theorem with topologic struct... 详细信息

关键词： branched continued fraction interpolation vector-grid

Formation of Ultrafine Metal Particles and Metal Oxide Precursor on Anodized Al by Electrolysis Deposition

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Journal of Materials Science & Technology 2000年第1期16卷 50-54页

作者： Lingchuan LI (institute of Chemical Metallurgy, Chinese Academy of Sciences, Beijing 100080, china) institute of Chemical Metallurgy Chinese Academy of Sciences Beijing 100080 China

Nickel was deposited by ac electrolysis deposition in the pores of the porous oxide film of Al produced by anodizing in phosphoric acid. Ultrafine rod-shaped Ni particles were formed in the pores. At the same time a film of Ni oxide precursor was developed on the surface of the porous oxide film. The Ni particles and the Ni oxide precursor were examined by SEM, TEM and X-ray diffraction. The thickness of the barrier layer of the porous oxide film was thin and it attributed to the formation of the metal particles, while the formation of the oxide precursor was associated with the surface pits which were developed in the pretreatment of Al.

关键词： Al Formation of Ultrafine Metal Particles and Metal Oxide Precursor on Anodized Al by Electrolysis Deposition

Fundamental study of CO_2 control technologies and policies in china

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Science china(Technological Sciences) 2008年第7期51卷 857-870页

作者： JIN HongGuang1, ZHANG XiLiang2, GAO Lin1, YUE Li2, HE JianKun2 & CAI RuiXian1 1 institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100080, china 2 institute of Nuclear and new Energy Technology, Tsinghua University, Beijing 100084, china institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China institute of Nuclear and new Energy Technology Tsinghua University Beijing China

The technical roadmap and policies for CO2 mitigation suitable for china are a common center of attention in the fields of energy, environment, and management science in the country. Emphasizing interaction between technical research and policy research, this work discovers the potential breakthrough in the integrated field. The technical difficulties of recovering CO2 are pointed out, the mechanism of combining CO2 recovery with energy conversion is investigated, and the basic principle for integrating an environmental-friendly energy system is discussed. Moreover, the formulation of a new energy system that can recover CO2 with very low or even zero energy penalty is proposed, while the assessment methodology and model system for the technical roadmap of CO2 emission control are developed. Finally, a new technical roadmap constructing an energy network suitable for china is proposed, which may provide a new way for the development of sustainable energy and environment technologies.

关键词： CO2 capture and storage technical roadmap energy policy