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Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3 ,HUANG Zhiqin 2. 3, 4.1. The Faculty of geography and Resources Science, Sichuan Normal university, Chengdu 610066, Sichuan, China 2. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 61004., Sichuan, China 3. Graduate university of the Chinese Academy of Sciences, Beijing 10004., China 4. Information Center of Land and Resources department of Sichuan Province, Chengdu 61004., Sichuan, China The Faculty of geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate university of the Chinese Academy of Sciences 100049 Beijing China Information Center of Land Resources department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

On the Average Number of Unitary Factors of Finite Abelian Groups (Ⅱ)

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Acta Mathematica Sinica,English Series 2000年第4期16卷 549-554页

作者： Wenguang Zhai department of Mathematics, Shandong Normal university. {2. 2.0014. P. B. China department of Mathematics Shandong Normal University Jinan 250014 P. R. China

Let t（G） be the number of unitary factors of finite abelian group G. In this paper we prove T（x）=∑(G≤（）t（G） =main terms+O(x(（1+2.）/（3+4.）for any exponent pair （k, 1/2.2.）. which improves on the exponen... 详细信息

关键词： Unitary factor Finite Abelian group Exponential sum Divisor problem

Integral spinor norms in dyadic local fields Ⅲ

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Science China Mathematics 2010年第9期53卷 2425-2446页

作者： L JianRui1 & XU Fei2.1department of Mathematics,jinan {2.,Guangzhou 510632.China 2.chool of Mathematics,Capital Normal {2.,Beijing 10004.,China department of Mathematics Jinan University Guangzhou China School of Mathematics Capital Normal University Beijing China

In this paper we give an alternative computation of integral spinor norms over dyadic local fields by using the Jordan decomposition of *** particular,we emphasize the striking similarity between the theory over dyadi... 详细信息

关键词： integral lattice spinor norm Jordan decomposition

Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2.molecule

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Science China(Physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2. SUN Weiguo1, HOU Shilin3 & FENG Hao4.1. Institute of Physics, College of Chemical Engineering, Sichuan university, Chengdu 610065, China 2. Institute of Theoretical Physics, Xihua Normal university, Nanchong 637002. China 3. {2. of Physics, China Oceanography university, Qingdao 2.6003, China 4. College of Physics, Sichuan university, Chengdu 610065, China 1. Institute of Physics College of Chemical Engineering Sichuan University 610065 Chengdu China 2. Institute of Theoretical Physics Xihua Normal University 637002 Nanchong China 3. department of Physics China Oceanography University 266003 Qingdao China 4. College of Physics Sichuan University 610065 Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2.molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

Theoretical Studies on Electronic Spectra and Second-order Nonlinear Optical Properties of N-methyl-2.（2.-thiophene）-pyrrolo[3,4.C60

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Chinese Chemical Letters 2001年第8期12卷 719-722页

作者： Ying LIU1, Yong Jun LIU2., Cheng Bu LIU2.1department of Chemistry, Qufu Normal university, Qufu 2.3165 2.nstitute of Theoretical Chemistry, Shandong university, jinan 2.0100 Qufu Normal Univ Dept Chem Qufu 273165 Peoples R China Shandong Univ Inst Theoret Chem Jinan 250100 Peoples R China

By using AM1 method, the structures and electronic properties of N-methyl-2.(2.-thiophene)-pyrrolo[3,4.C60 (MTPC) and N-methyl-pyrrolo[3,4.C60 (MPC) have been studied. Based on the AM1 geometry optimizing, the electronic spectra and second-order nonlinear optical polarizabilities (() of MTPC and MPC were calculated by using INDO/SCI method combined with Sum-Over-States (SOS) expression.

关键词： C60 derivatives electronic spectra and second-order nonlinear optical properties.

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. China 2. {2. of Mathematics and Physics, Shandong Institute of Architecture and Engineering, jinan 2.0014. China 3. Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, China 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.

USING MOIRE INTERFEROMETRY AND BOUNDARY INTEGRAL HYBRID METHOD TO DETERMINE MIXED-MODE STRESS INTENSITY FACTOR

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Acta Mechanica Sinica 1988年第4期4卷 319-326页

作者： Jia Youquan Xie jinan Wang Yinyan (department of Mechanics,Tianjin {2.) 1. department of Mechanics Tianjin University Tianjin China

The paper describes a hybrid experimental and numerical method of Moiré Interferometryand the boundary-integral-element *** interference patterns used for the evaluation of thedisplacement vector are obtained by Moiré *** boundary displacements obtainedexperimentally are conveniently used for the calculation of the stress intensity factor in the body by *** examples bear witness to the effectiveness and accuracy of the hybridtechnique.

关键词： Moiré interferometry method boundary integral element method hybrid method stress intensity factor

ALGEBRAIC APPROACH TO THE ROTATIONVIBRATIONAL SPECTRA FOR DIATOMIC MOLECULES

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原子与分子物理学报 1990年第4期7卷 1681-1687页

作者： Ding Shiliang, Yi Xizhang department of physics, Shandong university, {2., China.

The symmetry of group U(3) can be used to get the rotationvibrational spectra of a diatomic molecule without solving the schroedinger equation.

关键词：双原子分子旋转-振动谱代数方法

Calculation of the molecular exchanging energy of binary surfactants system on the surface monolayer of aqueous solution

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Science China Chemistry 2007年第4期50卷 468-475页

作者： WANG ZhengWu1 & YI XiZhang2.1 department of Food Sciences & Technology, School of Agriculture and Biology, Shanghai Jiao Tong university, Shanghai 2.02.0, China 2.Institute of Theoretical Chemistry, Shandong university, jinan 2.0100, China 1. department of Food Sciences & Technology School of Agriculture and Biology Shanghai Jiao Tong University Shanghai 200240 China 2. Institute of Theoretical Chemistry Shandong University Jinan 250100 China

By using the binary anionic/cationic surfactants system CH3(CH2.nOSO_3/CH3(CH2.nN+(CH3)3 as an ex-ample, the molecular exchanging energy (ε) of adsorption on the surface monolayer of aqueous solu-tion has been studied. ε can be obtained with two methods. One is from the relationship between ε and the molecule interaction parameter (β). This relationship is founded by considering that the adsorption of mixed surfactants on the surface monolayer of solution satisfies the dimensional crystal model condition under which β can be obtained by testing the surface tension of solution. The other is directly from the molecular structure of surfactants with the Lennard-Jones formula. The results for the studied system show that these two methods coincide well.

关键词： surfactant molecule exchanging energy dimensional crystal model