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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 800-211, Shanghai 201800, china 2. Department of Physics, shandong Normal University,{3. 3. shandong institute of architecture and engineering,{3. Shanghai institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaichina Department of Physicsshandong Normal Universityjinanchina shandong institute of architecture and {3.jinanchina

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, shandong institute of {3. and engineering, jinan 250101, 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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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 architecture and {3.,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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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. Department of Mathematics and Physics, shandong {3. of architecture and engineering, jinan 2.0014. china 3. {3. of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, china 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 = 20. 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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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, jinan 250061, {3. Department of Materials Science and engineering, shandong institute of architecture and Technology, jinan 2.0014. china shandong engineering and Technology Research Center of Super-hard Materials, Zoucheng 273.00, {3.) 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 (Fe3., Ni3., (Fe, Ni)3.) 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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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 {3. and engineering,jinan 2.0014.china Solid Mechanics Research Center Beihang University Beijing China shandong institute of architecture and {3. Jinan China

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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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, jinan 25003., china {3. of Materials Science and engineering, shandong University, jinan 250061, 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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DSC　STUDY　OF　MARTENSITIC　TRANSFORMATION　KINETICS　IN　A　Cu－Zn－Al－Mn－Ni　SHAPE　MEMORY　ALLOY

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Acta Metallurgica Sinica(English Letters) 1996年第1期9卷 56-58页

作者： GENG Guili BAI Yujun PENG Qifeng(institute for Materials engineering,shandong University of Technology,{3. 2.0014.china) shandong Univ of Technology Jinan China

The kinetics of the reversible martensitic transformation in a Cu-Zn-Al-Mn-Ni shape memory alloy has been studied by means of differential scanning *** apparent activation energy has been calculated and the kinetic equations of positive and adverse martensitic transformation have been established with the variations of temperature and time.

关键词： shape memory alloy positive and adverse martensitic transformation phase transformation kinetics DSC study

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Allocation of power generating and shipping of Hanjiang upstream cascade

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Progress in Natural Science:Materials International 2005年第8期15卷 733-741页

作者： LIU Junping1* and CHANG Mingqi 2,3.1. School of Civil engineering and architecture, Zhejiang University of Technology, Hangzhou 3.0014, china 2. {3. of Water Resources & Hydroelectric engineering, Xi'an University of Technology, Xi'an 710048, china 3. Shanxi {3. of Water Resources, Taiyuan 03.001, china) School of Civil engineering and architecture Zhejiang University of Technology Hangzhou 310014 China institute of Water Resources and Hydroelectric engineering Xi'an University of Technology Xi'an 710048 China Shanxi institute of Water Resources Taiyuan 030001 China

The optimal model and simulating model of the Hanjiang cascade reservoirs operation with one day as its calculating period are established to coordinate the contradictions between power generating and shipping. The optimal model is solved by progressive optimality algorithm method adopting the theory of large system decomposing and coordinating. By analyzing the water allocation results obtained from six schemes, which are two cascades, four cascades and seven cascades joint operation considering shipping or not, the contradiction degree between power generating and shipping is investigated and some joint operation schemes are proposed.

关键词： cascade power generating contradiction shipping optimal operation.

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Sol-gel preparation and spectroscopic study of the pyrophanite MnTiO_3.nanoparticles

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Science china Chemistry 2005年第3期48卷 210-215页

作者： ZHOU Guowei1, KANG Youngsoo2, LI Tianduo1 & XU Guiying3.1. School of Light Chemicals and Environmental engineering, shandong institute of Light Industry, {3. 250100, china 2. Department of Chemistry, Pukyong National University, Daeyeon-3.dong, Nam-gu, Pusan 608-73., Korea 3. Key Laboratory for Colloid and Interface of Ministry of Education of china, shandong University, {3. 250100, china School of Light Chemicals and Environmental engineering Shandong Institute of Light Industry Jinan China Department of Chemistry Pukyong National University Pusan Korea Key Laboratory for Colloid and Interface of Ministry of Education of china Shandong University Jinan China

The nanosized xerogel of titanium dioxide (TiO2) and manganese oxides (MnO2, Mn2O3. Mn3.4) was prepared by the sol-gel method using manganese chloride (MnCl2·4H2O) and titanium isopropoxide (Ti(O-iPr)4) as precursors in cetyltrimethylammonium bromide (CTAB)/ ethanol/H2O/HCl micelle solutions, following the calcinations of the produced powders at differ-ence temperatures. The nanostructure and phase composition of these nanoparticles were characterized with X-ray powder diffraction (XRD), transmission electron microscopy (TEM), en-ergy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The spectroscopic characterizations of these nanoparticles were also done with UV-Vis spectroscopy and laser Raman spectroscopy (LRS). XRD patterns show that the pyrophanite MnTiO3.phase was formed at the calcinations temperature of 900℃. The TEM images show that the nanoparti-cles are almost spherical or slight ellipose and the sizes are 50 nm on average. The UV-Vis spectra show that the nanosized MnTiO3.have significant absorption bands in the visible region. There are new absorption peaks of MnTiO3.nanoparticles in LRS compared with the pure TiO2 powder.

关键词： pyrophanite MnTiO3. nanoparticles, spectroscopy, CTAB micelle, sol-gel.

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