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The dynamical properties of Rydberg hydrogen atom near a metal surface

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Science china({1.,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,{2., china 2. Department of mathematics and physics, shandong institute of architecture and engineering,{2., 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 {1. and physics Shandong Institute of Architecture and Engineering 250014 Jinan China 3. institute of Theoretical {1. 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 optical near-field speckles and their first order statistics on the basis of the integral equations of electromagnetic field

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Science china({1.,Mechanics & Astronomy) 2004年第3期47卷 365-380页

作者： CHENG Chuanfu1, 2. SONG Hongsheng2. LIU Chunxiang2. REN Xiaorong2. ZHANG Ningyu3, TENG Shuyun1 & XU Zhizhan1 1. Shanghai institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P. O. Box 800-2.1, Shanghai 2.1800, china 2. Department of {2., shandong Normal University, jinan 25001., china 3. shandong institute of architecture and engineering, jinan 25001., china 1. Shanghai institute of Optics and Fine Mechanics Chinese Academy of Sciences P. O. Box 800-211 201800 Shanghai China 2. Department of {1. Shandong Normal University 250014 Jinan China 3. shandong institute of architecture and engineering 250014 Jinan China

From Helmholtz equation of the harmonic electromagnetic waves, the integral equations of the light field at the medium boundaries are obtained by use of the Green's theorem and are discretized into linear equation set with the values of the light field and its derivative as the unknowns. On solving the linear equation set, we realize the rigorous computations of the light fields at the boundaries. Then the intensities of the light waves scattered by the random self-affine fractal surfaces in the optical near-field are calculated, and the propagation characteristics, the evolutions of the contrast and the intensity probability density function of the near-field speckles are studied in detail. The near-field speckles are much different from the conventional speckles in the diffraction regions and in the imaging systems. There are obvious local fluctuations in the intensity distributions of the near-field speckles and such fluctuations disappear after propagating a distance of one wavelength from the medium surfaces. For the random surfaces with smaller lateral correlation lengths, the speckle contrasts approach the saturation values and the speckle fields approach Gaussian distribution within the near-field, while for the random surfaces with larger lateral correlation lengths, such evolutions become comparatively slow.

关键词： speckle, near-field optics, first order statistics, Green's function.

Morita contexts on the Hopf algebroid

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Science china {1. 2005年第7期48卷 958-971页

作者： YIN Yanmin School of Mathematical Sciences, Peking University, Beijing 1.0871. china Department of {1.,{2., jinan 2.01.1. china 1. School of Mathematical Sciences Peking University 100871 Beijing China 2. Department of {1. Shandong Institute of Architecture and Engineering 250101 Jinan China

We generalize the Morita theory to the Hopf algebroid and give the characterization of the surjectivity of one of the Morita context maps.

关键词： comodule algebra, generalized smash product, Morita context.

Intermediate processes and critical phenomena: Theory, method and progress of fractional operators and their applications to modern mechanics

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Science china({1.,Mechanics & Astronomy) 2006年第3期49卷 257-272页

作者： XU Mingyu1.& TAN Wenchang2.1. {1. of Applied mathematics, School of Math & System Science, {2. University, jinan 2.01.0, china 2. State Key Laboratory of Turbulence and Complex Systems & Department of Mechanics and engineering Science, Peking University, Beijing 1.0871. china 1. institute of Applied {1. School of Math & System Science Shandong University Jinan 250100 China 2. State Key Laboratory of Turbulence and Complex Systems & Department of Mechanics and {1. Science Peking University Beijing 100871 China

From point of view of physics, especially of mechanics, we briefly introduce fractional operators (with emphasis on fractional calculus and fractional differential equa- tions) used for describing intermediate processes and critical phenomena in physics and mechanics, their progress in theory and methods and their applications to modern me- chanics. Some authors’ researches in this area in recent years are included. Finally, prospects and evaluation for this subject are made.

关键词： fractional operators,intermediate processes,critical phenomena,modern mechanics

Scattering of SH waves induced by a symmetrical V-shaped canyon: a unified analytical solution

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Earthquake engineering and engineering Vibration 2012年第4期11卷 445-460页

作者： Zhang Ning Gao Yufeng Li Dayong Wu Yongxin Zhang Fei Geotechnical Research institute Hohai University Key Laboratory of Geomechanics and Embankment engineering(Hohai University) Ministry of Education College of Civil engineering&{1. Shandong University of Science and Technology

This paper reports a series solution of wave functions for two-dimensional scattering and diffraction of plane SH waves induced by a symmetrical V-shaped canyon with different shape ratios. A half-space with a symmetrical V-shaped canyon is divided into two sub-regions by using a circular-arc auxiliary boundary. The two sub-regions are represented by global and local cylindrical coordinate systems, respectively. In each coordinate system, the wave field satisfying the Helmholtz equation is represented by the separation of variables method, in terms of the series of both Bessel functions and Hankel functions with unknown complex coefficients. Then, the two wave fields are described in the local coordinate system using the Graf addition theorem. Finally, the unknown coefficients are sought by satisfying the continuity conditions of the auxiliary boundary. To consider the phase characteristics of the wave scattering, a parametric analysis is carried out in the time domain by assuming an incident signal of the Ricker type. Surface and subsurface transient responses demonstrate the characteristics and mechanisms of wave propagating and scattering.

关键词： SH-wave scattering V-shaped canyon topographic effect wave propagation earthquake ground motion wave function expansion method

Fabrication, microstructure and properties of SiCp/Cu heat sink materials

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Rare Metals 2006年第z2期25卷 232-236页

作者： KANG Suk-bong Korea institute of Machinery and Materials 66 Sangnam-dong Changwon 641-010 Korea

Cu-coated powder was fabricated by electroless plating process, and the composition and morphology of coated powder were studied. Moreover, Cu-30, 40, 50 vol.%SiCp heat sink materials were fabricated by hot pressing using coated and uncoated powder. And the microstructure and thermophysical properties of the heat sink materials were also studied. The results show that SiCp particles distribute uniformly in heat sink materials and the interface between SiCp particles and Cu matrix is clear and well bonded. On the condition of same volume fraction of SiCp, the thermal conductivity of the material using coated powder is larger than that of the material using uncoated powder. Under experiment conditions, the thermal conductivity and coefficient of thermal expansion of Cu-30 vol.%SiCp heat sink material is 2.6.2.W·m-1.K-1.and 9.9×1.-6/K (30-2.0 ℃) respectively. It provides important reference data for future experiments.

关键词： heat sink material electroless copper plating coefficient of thermal expansion thermal conductivity

Self-assembly structure formation on patterned InP surfaces

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Science china(Technological Sciences) 2009年第9期52卷 2732-2736页

作者： SU Ge1.2.CAO LiXin1.& LIU TianZhong3 1.{1. of Material Science and engineering,Ocean University of{2.,Qingdao 2.61.0,china 2.Nanoscale physics Research Laboratory,School of physics and Astronomy,the University of Birmingham,Edgbaston,Birmingham B1. 2.T,UK 3 College of Food Science and engineering,Ocean University of{2.,Qingdao 2.6003,china institute of Material Science and {1. Ocean University of China Qingdao 266100 China Nanoscale physics Research Laboratory School of Physics and Astronomy the University of Birmingham Edgbaston Birmingham B15 2TT UK College of Food Science and engineering Ocean University of China Qingdao 266003 China

Self-assembly of polystyrene spheres guided by patterned n-type InP substrates has been investigated. InP surfaces were patterned using a variety of methods including wet chemical etching,sputter coating,thermal evaporation,and photo lithography. The self-assembly of polystyrene spheres depended on the appearance of patterns and was affected by the deposition techniques (sputter coating and thermal evaporation) of Au micro-squares. SEM and AFM were used to characterize the surface morphologies.

关键词： self-assembly polystyrene spheres pattern InP surface

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非线性时滞系统最优控制的模糊逻辑方法

山东大学学报（理学版） 2004年第5期39卷 47-51,57页

作者：张宪福程兆林山东建筑工程学院数理系山东济南250014 山东大学数学与系统科学学院山东济南250100

基于T S模糊模型和平行分布补偿器 (PDC) ,讨论了非线性时滞系统的模糊最优问题 .最优控制器的设计程序转化为求一类受限于线性矩阵不等式 (LMI)的最优问题 ,而此最优问题的可行性解能够用有效的数值解法来确定 .

关键词：最优控制非线性时滞系统模糊模型 PDC LMI

Giant magnetoimpedance effect of multilayered structure(F/SiO_2._3/Ag/(SiO_2.F)_3 films deposited in a longitudinal magnetic field

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Science china(Technological Sciences) 2010年第3期53卷 287-292页

作者： CHEN WeiPing1,2.SHAO XianYi1,2.FENG ShangShen1,2.XIAO ShuQin3 & LIU YiHua3 1 School of physics and Electronics engineering,Zhejiang Taizhou University,Taizhou 318000,{2. 2.institute of Function Materials for Electronic Information,Zhejiang Taizhou University,Taizhou 318000,{2. 3 School of physics,shandong University,jinan 2.0100,{2. 1. School of physics and Electronics {1. Zhejiang Taizhou University Taizhou 318000 China2. Institute of Function Materials for Electronic Information Zhejiang Taizhou University Taizhou 318000 China3. School of Physics Shandong University Jinan 250100 China

The soft magnetic properties and giant magnetoimpedance(GMI) effect of the multilayered structure(F/SiO2.3/Ag/(SiO2.F)3(F≡Fe71.5Cu1.r2.5V4Si1.0}9) films,which were prepared by radio frequency sputtering without and with a longitudinal magnetic field of about 72.kA/m,are *** results show that the GMI effect almost cannot be detected in the samples deposited without field,whereas,a longitudinal magnetic field applied during deposition process obviously optimizes the soft magnetic properties of the films,and noticeable GMI effect is *** maximum values of the longitudinal and transverse GMI ratios are 45% and 44% at the frequency of 6.81.MHz,*** addition,the dependence of magnetoimpedance ratio,magnetoresistance ratio,magnetoreactance ratio and effective permeability ratio on the frequency has been *** found that the GMI spectrum curves in the longitudinal and transverse cases almost overlap for the field-deposited *** GMI effect is mainly a giant magnetoinductive effect at low *** f >9 MHz,magnetoreactance ratio changes to a negative,i.e.,the property of reactance changes from inductive to capacitive.

关键词： Fe-based soft magnetic alloy as-deposited multilayered films giant magnetoimpedance effect effective permeability magnetic anisotropy

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