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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, jinan 250014, china 2. department of mathematics and Physics, shandong institute of architecture and engineering, jinan 250014, 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.

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 engineering,jinan,250014,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.

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, china department of Materials Science and engineering, shandong institute of architecture and Technology, jinan 250014, china shandong engineering and Technology Research Center of Super-hard Materials, Zoucheng 273500, 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.

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 250031, china institute 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

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 250014, china 2. department of mathematics and Physics, shandong institute of architecture and engineering, jinan 250014, china 3. institute 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.

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, jinan 250014, china 3. shandong institute of architecture and engineering, jinan 250014, china Shanghai institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaichina department of Physicsshandong Normal Universityjinanchina shandong institute of architecture 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.

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,jinan 250014,china Solid Mechanics Research Center Beihang University Beijing China shandong institute of architecture and engineering 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

Microstructure and diffraction pattern changes resulted from long-term aging of martensite CuZnAlMnNi shape memory alloy

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Rare Metals 2002年第4期21卷 308-312页

作者： BAIYujun WANGShouren 等 Mechanicaldepartment ShandongUniversityofScienceandTechnologyJinan250031China instituteofMechanicalengineering JinanUniversityJinan250022China

Microstructures of a CuZnAlMnNi shape memory alloy in the as-quenched andlong-term aged conditions were investigated by transmission electron microscopy. Aged for one yearin martensite phase, an equilibrium α-phase with fcc structure was observed in the M18R martensitematrix, accompanied by the appearance of a novel diffraction pattern. By analysis, it was suggestedthat the novel pattern results from the α-phase and the martensite matrix remaining in seven fineplates which produce intense secondary diffraction effect when the diffraction beams enter from onephase into another.

关键词： CuZnAlMnNi shape memory alloy martensite aging transmission electronmicroscopy

Cloning,Sequencing and Expression Analysis of the First Cellulase Gene Encoding Cellobiohydrolase 1 from a Cold-adaptive Penicillium chrysogenum FS010

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 101-107页

作者： Yunhua HOU~(1,2) Tianhong WANG~1 Hao LONG~1 and Huiynan ZHU~(1,2) ~1State Key Laboratory of Microbial Technology,shandong University,jinan 250100,china ~2department of Food and Biologic engineering,shandong institute of Light Industry,jinan 250323,china State Key Laboratory of Microbial Technology Shandong University Jinan 250100 China department of Food and Biologic engineering Shandong Institute of Light Industry Jinan 250323 China

A cellobiohydrolase 1 gene (cbhl) was cloned from Penicillium chrysogenum FS010 by amodified thermal asymmetric interlaced polymerase chain reaction (TAIL-PCR).DNA sequencing showsthat cbhl has an open reading frame of 1590 bp, encoding a putative protein of 529 amino acid *** amino acid sequence revealed that CBHI has a modular structure with a predicted molecular massof 56 kDa and consists of a fungal type carbohydrate binding module separated from a catalytic domain bya threonine rich linker *** putative gene product is homologous to fungal cellobiohydrolases inFamily 7 of the glycosyl hydrolases.A novel cbhl promoter (1.3 kb) was also cloned and sequenced,whichcontains seven putative binding sites (5'-SYGGRG-3') for the carbon catabolite repressor *** ofvarious carbon sources to the cbhl transcription of *** was examined by Northern analysis,suggesting that the expression of cbhl is regulated at transcriptional *** cbhl gene in cold-adaptivefungus *** was expressed as an active enzyme in Saccharomyces cerevisiae *** recombinantCBHI accumulated intracellularly and could not be secreted into the medium.

关键词： Penicillum chrysogenum cellobiohydrolase TAIL-PCR promoter of cbh1