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Issues of the Holocene transgression on the southern plain of the Changjiang Delta

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Acta Oceanologica Sinica 1988年第4期7卷 578-590页

作者： Yan Qinshang and Hong Xueqing department of geography, East {2. {3. university, Shanghai, {2. Dept. of geography East China Normal Univ. Shanghai China. China

The paper deals with the question of Holocene transgression on the southern plain of the Changjiang *** the beginning of the transgression, the paleovalleys of the Changjiang and Qiantang Rivers were covered by sea water at *** shoreline of 8000-7500 yr BP coincided with the -7m isobath of paleotopography. Sea level had already been the present level about 7000-6500 years ago, and the Holocene transgression reached its maximum extent. During the period, the Changjiang and Qiantang Rivers and the Dongtiaoxi valley were turned into estuaries; the eastern area of Shanghai became a shallow sea; some of the bays and lagoons were distributed on the Hang-Jia-Hu and Tao-Ge Plain; the hilly region around the Taihu Lake was coastal marsh and freshwater swamp. Gangshen on the west of Shanghai was formed 7000-4000 yr BP, and during the last 4000 years, the eastern coastal plain of Shanghai advanced quickly toward the sea, and partial clear land of the western Taihu Lake was enclosed and charged into a fre

关键词： Ho Issues of the Holocene transgression on the southern plain of the Changjiang Delta

Impact on the Yangtze (Changjiang) Estuary from its drainage basin: Sediment load and discharge

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Chinese Science Bulletin 2001年第S1期46卷 73-80页

作者： CHEN Zhongyuan & ZHAO YiwenState Key Laboratory for Estuarine and Coastal Research, East china normal {2., Shanghai 2.0062. china department of geography, East china normal {2., Shanghai 2.0062. china 1. State Key Laboratory for Estuarine and Coastal Research East China Normal University 200062 Shanghai China 2. department of geography East China Normal University 200062 Shanghai China

This paper focuses on the sediment transport and freshwater discharging from upper Yangtze drainage basin downstream, primarily on the basis of multiyear hy-drological data collected from three major hydrological gauge stations (Yichang, Hankou and Datong). Data indicate highest sediment load in Yichang (5.6×108 t/a), lowest in Hankou (5.1×108t) and second highest in Datong (5.4×108 t). This fluctuations are identical with what has been observed from the annual flood season. About one thirds of the sediment load are trapped in the middle Yangtze River course, where meandering river pattern prevails; rest of them are directly transported to the river mouth area via lower Yangtze River channel, where the river is typically confined by the exposed base rock and almost none is being trapped, instead, minor being drained to the mainstream from the local tributaries. To recognize this sediment delivery and river flow media is vital, because it can highlight morphologic/topographic correlation between the

关键词： sediment load discharge estuarine impact the Yangtze River.

A new definition of restricted Lie superalgebras

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Chinese Science Bulletin 2000年第4期45卷 316-321页

作者： WANG Ying & ZHANG Yongzheng1. department of Mathematics, Harbin Institute Technology, Harbin 150001, china 2. department of Mathematics, Northeast normal university, Changchun 13.02., china department of Mathematics Harbin Institute Technology Harbin China department of Mathematics Northeast Normal University Changchun China

A new definition of restricted Lie superalgebras has been given; some important results on the representation theory of restricted Lie superalgebra have been obtained.

关键词： restricted Lie superalgebra p-mapping p-semilinear mapping α-representation.

Improvement of a 3. radar backscattering model using matrix-doubling method

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Science china Earth Sciences 2010年第7期53卷 1029-1035页

作者： NI WenJian1,2. GUO ZhiFeng1 & SUN GuoQing3.1 State Key Laboratory of Remote Sensing Science, jointly sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing normal university, Beijing 100101, {2. 2.Graduate university of Chinese Academy of Sciences, Beijing 100049, {2. 3.department of geography, university of Maryland, College Park, MD 2.042. USA 1. State Key Laboratory of Remote Sensing Science jointly sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Department of Geography University of Maryland College Park MD 27042 USA

Radiative transfer models have been widely used to simulate the radar backscattering from forested areas. A three-dimensional radar backscatter model of forest canopy developed in previous studies takes full account of spatial position of trees in a forest stand, and the interactions among crown, trunk and ground surface. The model predicted well for the co-polarized backscatter measurements, but underestimated the backscattering for cross-polarization, primarily because only the first-order scattering within tree crowns was considered in the model. The backscattering at cross-polarization depends strongly on multiple scatter- ing within tree crowns. To produce good estimations for cross-polarized component, the matrix-doubling method is employed here to compute multiple-scattering within the crown. The modified model is compared with the original model, and the field forest measurements and AIRSAR data are used for validation of the modified model. The cross-polarization backscattering is improved in different degrees for different crown structures and at different bands.

关键词： remote sensing forestry electromagnetic propagation radar backscattering model matrix-doubling

On solving equations of algebraic sum of equal powers

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Science china Mathematics 2006年第9期49卷 1153-1157页

作者： WANG Xinghua & YANG Shijun department of Mathematics, zhejiang {2., Hangzhou 3.002., china department of Mathematics, Hangzhou normal College, Hangzhou 3.003., china department of Mathematics Zhejiang University Hangzhou 310028 China department of Mathematics Hangzhou Normal College Hangzhou 310036 China

It is well known that a system of equations of sum of equal powers can be converted to an algebraic equation of higher degree via Newton's identities. This is the Viete-Newton theorem. This work reports the generalizations of the Viete-Newton theorem to a system of equations of algebraic sum of equal powers. By exploiting some facts from algebra and combinatorics,it is shown that a system of equations of algebraic sum of equal powers can be converted in a closed form to two algebraic equations, whose degree sum equals the number of unknowns of the system of equations of algebraic sum of equal powers.

关键词： algebraic sum of equal powers, Newton's identities, system of equations,roots of a polynomial.

Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

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Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2.1 department of Physics, china {2. of Petroleum, Dongying 2.7061, china 2.department of Physics, Beijing normal {2., Beijing 100875, china department of Physics China University of Petroleum Dongying 257061 China department of Physics Beijing Normal University Beijing 100875 China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

The dynamical properties of Rydberg hydrogen atom near a metal surface

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 667-675页

作者： GE Meihua1, ZHANG Yanhui1, WANG Dehua2. DU Mengli3.& LIN Shenglu1 1. College of Physics and Electronics, Shandong normal university, Jinan 2.0014, {2. 2. department of Mathematics and Physics, Shandong Institute of Architecture and Engineering, Jinan 2.0014, {2. 3. Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, {2. 1. College of Physics and Electronics Shandong Normal University 250014 Jinan China 2. department of Mathematics and Physics Shandong Institute of Architecture and Engineering 250014 Jinan China 3. Institute of Theoretical Physics Chinese Academy of Sciences 100080 Beijing China

The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion clearly. In this paper we choose the atomic principal quantum number as n = 2.. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distance d. When d is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system is integrable. When d becomes smaller, there exists a critical value dc. For d > dc, the system is near-integrable and the motion is regular. While chaotic motion appears for d < dc, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the metal surface.

关键词： Rydberg hydrogen atom, van der Waals interaction, Poincaré surface of section, closed orbit theory, chaos.

The kink-soliton and antikink-soliton in quasi-one-dimensional nonlinear monoatomic lattice

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Science china(Physics,Mechanics & Astronomy) 2005年第2期48卷 150-157页

作者： XU Quan1 & TIAN Qiang2.1. Scientific and Technological Office, Daqing Teacher College, Daqing 163.12. china 2. department of Physics , Beijing {2. university, Beijing 100875, china Scientific and Technological Office Daqing Teacher College Daqing 163712 China department of Physics Beijing Normal University Beijing 100875 China

The quasi-one-dimensional nonlinear monoatomic lattice is analyzed. The kink-soliton and antikink-soliton are presented. When the interaction of the lattice is strong in the x-direction and weak in the y-direction, the two-dimensional (2.) lattice changes to a quasi-one-dimensional lattice. Taking nearest-neighbor interaction into account, the vibration equation can be transformed into the KPI, KPII and MKP equation. Considering the cubic nonlinear potential of the vibration in the lattice, the kink-soliton solution is presented. Considering the quartic nonlinear potential and the cubic interaction potential, the kink-soliton and antikink-soliton solutions are presented.

关键词： two-dimensional nonlinear lattice, quasi-one-dimensional nonlinear lattice, kink-soliton, antikink-soliton.

Nonlinear properties of fractal growth of thin films at low temperature

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Communications in Nonlinear Science and Numerical Simulation 2001年第2期6卷 61-67页

作者： Fengmin WU, Jiefang ZHANG, Gen BIAN and Ziqin WU Research Center of Science, zhejiang university of Technology, Hangzhou 3.0014, {2. Institute of Nonlinear Physics,{3., jinhua 3.1004, {2. Shao Yifu Hospital of zhejiang Provin Research Center of Science Zhejiang University of Technology Hangzhou 310014 China Institute of Nonlinear Physics Zhejiang Normal University Jinhua 321004 China Shao Yifu Hospital of zhejiang Province Hangzhou 310005 China department of Astronomy and Applied Physics University of Science and Technology of China Hefei 230026 China

Fractal growth of thin films at low temperature (75-2.0 K) is simulated by kinetic Monte Carlo method, using realistic growth model-Ag on Pt(111) surface and physical parameters. It is shown that the fractal growth of thin films is nonlinear, i. e., the island size S(t) grows with time t as tk ) where the growth exponent k is slightly less than 1 because of the growth competition of islands and the competition between nucleation and growth of islands. The further results indicate that the branch width of islands b increases with increasing island size S as b -Sa, where a is approximately equal to 1/3.because of the geometrical structure of the triangular substrate.

关键词： fractal growth thin film Monte Carlo method