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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(Physics,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. {2. of Physics, shandong Normal University, jinan 2.0014, china 3. shandong institute of architecture and engineering, jinan 2.0014, china Shanghai institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaichina department of Physicsshandong Normal University{2.china shandong institute of {2. and engineeringjinanchina

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.

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Morita contexts on the Hopf algebroid

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Science china Mathematics 2005年第7期48卷 958-971页

作者： YIN Yanmin School of Mathematical Sciences, Peking University, Beijing 100871, china department of Mathematics,{2., jinan 2.0101, china School of Mathematical Sciences Peking University Beijing 100871 China department of Mathematics Shandong Institute of Architecture and Engineering Jinan 250101 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.

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Recurrence spectra of He atoms in strong external fields

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Science china(Physics,Mechanics & Astronomy) 2004年第4期47卷 477-484页

作者： LIN Shenglu1, LI Hongyun1, WANG Dehua2. ZHAO Wenli1 & GAO Feng1 1. department of Physics, shandong Normal University, {2. 2.0014, china 2. department of Mathematics and Physics, shandong institute of architecture and engineering, {2. 2.0014, china department of Physics Shandong Normal University Jinan China department of Mathematics and Physics Shandong Institute of Architecture and Engineering Jinan China

By employing a model potential including the electron exchange energy, we extend the semiclassical closed orbit theory to study the multielectron atoms. Using special region-splitting consistent and iterative method, we figure out the closed orbits in the corresponding classical system and calculate the recurrence spectra of triplet helium atoms in parallel electric and magnetic fields at scaled energy ε=?0.03,n≈40,n=0. The core-scattering effects have been taken into account, which lead to more peaks in the spectra. It has also been confirmed by means of the direct comparison between the spectral portrait in such a plot and those of hydrogen case. In order to compare the theoretic results with experiment, we investigate the closed orbits and recurrence spectra of helium atoms for the similar exchange potential but applied only by single electric field at scaled energy ε=?2.7 case. The spectra are in good agreement with the experimental observation. We conclude that our model is correct and it is necessary to consider the exchange effect for determining the photoabsorption spectra of multielectron atoms in strong external fields.

关键词： exchange potential, recurrence spectra, semiclassical closed orbit theory, core-scattering.

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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. College of Physics and Electronics Shandong Normal University Jinan China department of Mathematics and Physics Shandong Institute of Architecture and Engineering Jinan China institute of Theoretical Physics Chinese Academy of Sciences 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.

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A　Fast　Recursive　Algorithm　for　Positive　and　Inverse　in　Damped　Wave　Equation　Problems

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Systems Science and Systems engineering 1994年第4期4卷 357-362页

作者： QIU Zhongfang(shandong institute of {2. and engineering,jinan,2.0014,china)

Based on the damped wave equation,the damped wave equation for seismic exploration is given for the study on evaluation problem of stratum acoustic impedance by the seismic data *** applying Cauchy Problem instead of mixed problem in the process Of identifying acoustic impedance,we for give a fast identification algorithm of recurtive layer by *** order to avoid the accumulation of errors while identifying,the method of removing errors layer by layer is *** using the principle of Pulse Variation and even under the circumstance of big noise,we can identify the structure of stratum clearly.

关键词： damped wave equation impedance identification seismic exploration Cauchy Problem principle of Pulse Variation.

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Valance electron structure of carbide-diamond interface and catalytic mechanism for diamond synthesis under high-pressure and high-temperature

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Progress in Natural Science:Materials International 2006年第8期16卷 852-858页

作者： GONG Jianhong, XU Bin, YIN Longwei, QI Yongxin, LI Li, SU Qingcai and LI Musen (School of Materials Science and engineering, shandong University, {2. 2.0061, china department of Materials Science and engineering, shandong institute of architecture and Technology, {2. 2.0014, china shandong engineering and Technology Research Center of Super-hard Materials, Zoucheng 2.3500, china) School of Materials Science and engineering Shandong University Jinan 250061 China. shandong engineering and Technology Research Center of Super-hard Materials Zoucheng 273500 China. department of Materials Science and engineering Shandong Institute of Architecture and Technology Jinan 250014 China

The metallic films surrounding a synthetic diamond formed under high-pressure and high-temperature (HPHT) in the presence of Fe-based and Ni-based catalysts were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was showed that the carbide was the primary carbon source for the nucleation and growth of diamond. Based on the EET (empirical electron theory in solid and molecules) theory, the valence electron structure of interface between carbide (Fe3C, Ni3C, (Fe, Ni)3C) and diamond was calculated using the bonding length difference (BLD) method. The boundary criterion of Thomas-Fermi-Dirac-Cheng (TFDC): "the electron density being equal on the contacting surfaces of atoms" was applied to analyze the valence structure of carbide-diamond interface. The result based on the calculation valance electron structure is in good accordance with the experimental result. This study is very helpful to reveal the catalytic mechanism of diamond nucleation and growth and design the new catalyst for diamond synthesis.

关键词： synthetic diamond carbide catalytic mechanism valence electron theory interface.

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Influence of Heating Rate on Double Reversible Transformation in CuZnAlMnNi Shape Memory Alloy

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Rare Metals 2001年第2期20卷 117-120页

作者： Yujun Bai, Chengwei Lu, Xiangang Xu, Guili Geng, Longwei Yin (Mechanical department, shandong University of Science and Technology, {2. 2.0031, china institute of Materials Science and engineering, shandong University, {2. 2.0061, china) 山东理工大学山东济南 250031 山东大学山东济南 250061

The influence of heating rate on double reversible transformation in CuZnAlMnNi shape memory alloy was investigated by differential scanning calorimetry. It was found that rapid heating inhibits X -->M transformation but is favorable to the reverse martensite transformation, giving rise to the approach of the two transformation peaks. With the decrease of heating rate, the two transformation peaks separate gradually.

关键词： double reversible transformations heating rate CuZnAlMnNi shape memory alloy differential scanning calorimetry

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Elastic-plastic contact force history and response characteristics of circular plate subjected to impact by a projectile

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Acta Mechanica Sinica 2007年第4期23卷 415-425页

作者： L.B.Chen F.Xi J.L.Yang Solid Mechanics Research Center,Beihang University,Beijing 100083.china shandong institute of architecture and engineering,{2. 2.0014,china Solid Mechanics Research Center Beihang University shandong institute of {2. and engineering

A new elastic-plastic impact-contact model is proposed in this paper. By adopting the principle of minimum acceleration for elastic-plastic continue at finite deformation, and with the aid of finite difference method, the proposed model is applied in the problem of dynamic response of a clamped thin circular plate subjected to a projectile impact centrally. The impact force history and response characteristics of the target plate is studied in detail. The theoretical predictions of the impact force and plate deflection are in good agreements with those of LDA experimental data. Linear expressions of the maximum impact force/transverse deflection versus impact velocity are given on the basis of the theoretical results.

关键词： Elastic-plastic contact model ImpactCircular plate Contact force Minimum principleof acceleration

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

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

作者： XU Mingyu1 & TAN Wenchang2.1. institute of Applied Mathematics, School of Math & System Science, shandong University, {2. 2.0100, china 2. State Key Laboratory of Turbulence and Complex Systems & department of Mechanics and engineering Science, Peking University, Beijing 100871, china nl.gov institute of Applied Mathematics School of Math & System Science Shandong University Jinan 250100 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

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Relations among the category of topological molecular lattices and certain related categories

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Chinese Science Bulletin 1997年第8期42卷 636-640页

作者： WANG Guojun and LI Yongming1. institute of Mathematics, Shaanxi Normal University, Xi’an 710062. china 2. {2. of Basic Science, Northwestern institute of architecture engineering, Xi’an 710061, china institute of Mathematics Shaanxi Normal University Xi’an China department of Basic Science Northwestern Institute of Architecture Engineering Xi’an China

TAKING the theory of fuzzy topology and point set topology as background,the theory of topo-logical molecular lattices was first advanced in 1979,and after several generalizationsrefs.[4,5] are its general *** topology and point set topology are both special casesof topological molecular lattices as pointed out in ref.[4],whereas it seems not clear whetherone can develop the theory of topological molecular lattices by means of methods in

关键词： category pick-up-one principle.

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