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百种中国杰出学术期刊获奖证明

动物营养学报 2024年第8期 4754-4754页

作者： institute of Scientific and Technical Information of china 中国科学技术信息研究所

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中国科技核心期刊(中国科技论文统计源期刊)收录证书

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中国医学影像学杂志 2024年第5期 529-529页

作者： institute of Scientific and Technical Information of china 中国科学技术信息研究所

CERTIFICATE OF SOURCE JOURNAL FOR CHINESE SCIENTIFIC AND TECHNICAL PAPERS AND CITATIONS中国医学影像学杂志经过多项学术指标综合评定及同行专家评议推荐,贵刊被收录为“中国科技核心期刊”(中国科技论文统计源期刊)。特颁发此证书。

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Modeling of elastic wave propagation on a curved free surface using an improved finite-difference algorithm

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Science china(Physics,Mechanics & Astronomy) 2004年第5期47卷 633-648页

作者： WANG Xiuming1,3.& ZHANG Hailan2 1. CSIRO Petroleum, ARRC, PO BOX 113., Technology Park, Bentley, WA 6102, Australia 2. institute of Acoustics, Chinese Academy of Sciences, beijing 100080, china 3. Present address: institute of Acoustics, Chinese Academy of Sciences, beijing 100080, china CSIRO Petroleum ARRC Bentley Australia institute of Acoustics Chinese Academy of Sciences Beijing China

Based on existing direct and imaging methods of a staggered finite-difference scheme, an improved algorithm for staggered finite-difference is proposed to implement rugged topographic free boundary conditions. This method assumes that the free surface can be implemented with horizontal and vertical free surface segments and their corners; the free surface passes through the grid points of shear stress components, instead of the normal stress components. Imaging is carried out for stress components in both horizontal and vertical directions, thus increasing the accuracy. To update particle- velocities, imaging and updating are first performed in the horizontal direction, and then in the vertical direction. The numerical results for elastic flat horizontal free surface with the imaging method and those for flat free surfaces of various slope angles with the proposed method are compared, and are shown to be in good agreement. The advantage of the proposed method is that only the stresses are dealt with in implementing the free surface into the staggered algorithm, which improves computation efficiency.

关键词： elastic wave simulation, curved free surface, staggered finite-difference, algorithm stability.

Carbon isotope ratios of C_(4) plants in loess areas of North china

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Science china Earth Sciences 2006年第1期49卷 97-102页

作者： WANG Guoan1,2,3. HAN Jiamao 2, ZHOU Liping3. XIONG Xiaogang4, TAN Ming2, WU Zhenhai5 & PENG Jun6 1. Department of Plant Nutrition, china Agricultural University, beijing 100094, china 2. {3. of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china 3. College of Environmental Sciences, MOE Laboratory for Earth Surface Processes, Peking University, beijing 100871, china 4. {3. of Botany, Chinese Academy of Sciences, beijing 100093. china 5. Northwest Sci-Tech University of Agriculture and Forestry, Yangling 712100, china 6. Network Center, china Agricultural University, beijing 100094, china Department of Plant Nutrition China Agricultural University Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China College of Environmental Sciences MOE Laboratory for Earth Surface Processes Peking University Beijing China institute of Botany Chinese Academy of Sciences Beijing China Northwest Sci-Tech University of Agriculture and Forestry Yangling China Network Center China Agricultural University Beijing China

Carbon isotope ratios (δ^(13.C) of 89 C_4 plant samples were determined fromthe loess area in North china. δ^(13.C values vary between -10.5per thousand and -14.6per thousandwith a mean of -12.6per thousand. Along a precipitation gradient from the semi-moist area to thesemiarid area, then to the arid area, the δ^(13.C values of C_4 plants show a slight decreasingtrend. The δ^(13.C values of C_4 plants in the dry season are found lower than those in the wetseason. These trends are opposite to those observed for C_3.species.

关键词： C4 plants, carbon isotope ratios, loess area.

Paleomagnetic dating of the Cenjiawan Paleolithic site in the Nihewan Basin, northern china

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Science china Earth Sciences 2006年第3期49卷 295-303页

作者： WANG Hongqiang1,2, DENG Chenglong1, ZHU Rixiang1 & XIE Fei3.1. Paleomagnetism and Geochronology Laboratory (SKL-LE), institute of Geology and Geophysics, Chinese Academy of Sci- ences, beijing 100029, china 2. School of the Earth Sciences and Resources, china University of Geosciences, beijing 100083. china 3. Hebei Province institute of Cultural Relics, Shijiazhuang 050000, china Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China School of the Earth Sciences and Resources China University of Geosciences Beijing China Hebei Province institute of Cultural Relics Shijiazhuang China

Rock magnetic and magnetostratigraphic investigations on a lacustrine sequence in the Nihewan Basin, northern china, which bears the Cenjiawan Paleolithic site, indicate that the dominant magnetic mineral and remanence carrier contained in the sediments is magnetite. While hematite co-exists with magnetite in some portions of the Cenjiawan sequence, where characteristic remanent magnetizations are carried by both magnetite and hematite. Measurements of anisotropy of magnetic susceptibility confirm that the Cenjiawan sequence has preserved the original sedimentary features and is suitable for magnetostratigraphic study. Paleomagnetic results indicate that the Cenjiawan Paleolithic site is formed just posterior to the Punaruu normal event, which is dated at about 1.1 Ma. Combined with the paleomagnetic results of the Donggutuo, Xiaochangliang and Majuangou sections, it is concluded that early humans were occupying the Nihewan Basin around 1.6, 1.3.and 1.1 Ma. This integrated result is significant to understanding the ability of migration and adaptation to the envi- ronment of early humans.

关键词： Nihewan Basin, Early Pleistocene, Cenjiawan, Paleolithic site, paleomagnetism.

Node ordinal encoded genetic algorithm for the optimal allocation of water resources

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Progress in Natural Science:Materials International 2005年第5期15卷 448-452页

作者： YANG Xiaohua1*, YANG Zhifeng 1,2, SHEN Zhenyao1 and LI Jianqiang3.1. State Key Laboratory of Water Environment Simulation, School of Environment, beijing Normal University, beijing 100875, china 2. Key Laboratory for Water and Sediment Sciences Ministry of Education, School of Environment, beijing Normal University, beijing 100875, china 3. Water Resources and Hydropower Planning and Design General institute, MWR, beijing 100011, china) State Key Lab. of Water Environ. Simulation Sch. of Environ. Beijing Normal Univ. Beijing 100875 China Key Lab. for Water and Sediment Sci. Min. of Edu. Sch. of Environ. Beijing Normal Univ. Beijing 100875 China Water Resources and Hydropower Planning and Design General Inst. MWR Beijing 100011 China

A new method, node ordinal encoded genetic algorithm (NOEGA), is proposed for solving water resources optimal allocation problems, in which the capacity of water resources is split into a number of smaller parts so that successive operations can be overlapped. Our objective is to maximize the whole benefit function. To overcome the “dimensionality and algorithm complexity curse” while searching for solutions and looking for an optimal solution, the operations of one-point crossover operator, gene exchange operator, gene random operator, gene shift operator and node ordinal strings are established. It is proved to be an effective optimal method in searching for global solutions. The NOEGA does not need a diversity of initial population, and it does not have the problem of immature convergence. The results of two cases show that using NOEGA to solve the optimal allocation model is very efficient and robust. In addition, the algorithm complexity of NOEGA is discussed.

关键词： water resources optimal allocation node ordinal code genetic algorithm.

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,{3. 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

Theoretical study on the reaction mechanism of(CH_3._3.O+CO

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Science china Chemistry 2005年第1期48卷 18-24页

作者： ZHAO Hongmei1,2,3. SUN Chengke1,4, ZHANG Rongchang3. XI Hongmin3.& LI Zonghe1 1. Department of Chemistry, beijing Normal University, beijing 100875, china 2. The Laboratory of Molecular Reaction Dynamics, {3. of Chemistry, Chinese Academy of Sciences, beijing 100080, china 3. Department of Chemistry, Beihua University, Jilin 13.013. china 4. Department of Chemistry, Qujing Normal University, Yunnan 655000, china Department of Chemistry Beijing Normal University Beijing China The Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing China Department of Chemistry Beihua University Jilin China Department of Chemistry Qujing Normal University Yunnan China

The reaction mechanism of (CH3.3.O with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3.YP/6-3.G* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-3.++G** level. The results show that the reaction is multi-channel and the reaction of (CH3.3.O radical with CO mostly produces (CH3.3. + CO2. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3.YP, (CH3.3.O, radical.

Two－Side　Electron　Beam　Pumping　System　For　Hundred－Joule－Level　KrF　Excimer　Laser

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Chinese Journal of Lasers 1996年第6期B5卷 485-491页

作者： MA Weiyi SHAN Yusheng ZHOU Kungong WANG Youtian ZHANG Dong WU Fangfang YANG Zhe WANG Naiyan (china institute of atomic {3., P. O. for 275-7, beijing 102.13,china) china Inst of atomic energy Beijing China

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关键词： KrF excimer laser pulsed power system