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Theoretical study of ZnO adsorption and bonding on Al_2O_3.0001) surface

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Science china(physics,Mechanics & Astronomy) 2004年第6期47卷 664-675页

作者： LI Yanrong1,YANG Chun1,2,XUE Weidong1,LI Jinshan3.& LIU Yonghua3.1.Institute of Microelectronics and Solid State Electronics,university of Electronic Science and Technol- ogy of china,Chengdu 610054,china 2.Institute of Mathematics and Software Science,Sichuan Normal university,Chengdu 610068,china 3.Institute of Chemical Materials,china Academy of engineering physics,Mianyang 621000,china Institute of Microelectronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China Institute of Mathematics and Software Science Sichuan Normal University Chengdu 610068 China Institute of Chemical Materials China Academy of Engineering Physics Mianyang 621000 China

ZnO adsorption on sapphire (0001) surface is theoretically calculated by using a plane wave ultrasoft pseudo-potential method based on ab initio molecular dynamics. The results reveal that the surface relaxation in the first layer Al-O is reduced, even eliminated after the surface adsorption of ZnO, and the chemical bonding energy is 43..3.±3..6) kJ·mol?1. The chemical bond of ZnO (0.185 ± 0.01 nm) has a 3.° angle away from the adjacent Al-O bond, and the stable chemical adsorption position of the Zn is deflected from the surface O-hexagonal symmetry with an angle of about 3.°. The analysis of the atomic populations, density of state and bonding electronic density before and after the adsorption indicates that the chemical bond formed by the O2 of the ZnO ? and the surface Al3. has a strong ionic bonding characteristic, while the chemical bond formed by the Zn2+ and the surface O2 has an obvious covalent characteristic, which ? comes mainly from the hybridization of the Zn 4s and the O 2p and partially from that of the Zn 3. and the O 2p.

关键词： α-Al2O3.(0001) ZnO ab initio molecular dynamics chemical adsorption density of states

Formation of complexes of Rubisco-Rubisco activase from La^3., Ce^3. treatment spinach

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Science china Chemistry 2005年第1期48卷 67-74页

作者： HONG Fashui1, LIU Chao1, ZHENG Lei1, WANG Xuefeng1, WU Kang1, SONG Weiping1, Lü Shipeng1, TAO Ye2 & ZHAO Guiwen3.1. College of Life Sciences, Suzhou Universty, Suzhou 215006, china 2. Synchrotron Radiation Laboratory, Institute of High energy physics, The Chinese Academy of Science, Beijing 10003., china 3. Chemical Department, university of Science and Technology of china, Hefei 23.026, china College of Life Sciences Suzhou Universty Suzhou China Synchrotron Radiation Laboratory Institute of High Energy Physics The Chinese Academy of Science Beijing China Chemical Department University of Science and Technology of China Hefei China

The complex of Rubisco and Rubisco activase from LaCl3., CeCl3. treated spinach in vivo is induced. SDS-PAGE result shows that the purified proteins from LaCl3., CeCl3. treated spinach have not only large and small subunits (55 kD, 14.4 kD) of Rubisco, but also two large subunits of 45 kD and 41 kD near the large subunits of Rubisco. Native-PAGE shows that the purified proteins from LaCl3., CeCl3. treated spinach have not only a band of Rubisco (560 kD), but also a band of about 1100 kD, about twice distant from Rubisco, which might be a complex of Rubisco and Rubisco activase. The purified enzyme activities from LaCl3., CeCl3.treated spinach are 1.8 and 2.8 times that of the control,the intensities of absorption and fluorescence are sig- nificantly higher than that of the purified Rubisco from the control, and the total sulfhydryl groups and available sulfhydryl groups are 3.—3. –SH per mol enzyme, 14—25 –SH per mol enzyme more than those of the purified Rubisco from the control, respectively. The CD spectra show that the secondary structure of the purified enzyme from LaCl3., CeCl3.-treated spinach is very dif- ferent from the control. The enzyme activities from LaCl3., CeCl3. treated spinach in vivo are 1.5 and 1.9 times those of the control.

关键词： La3., Ce3., spinach, Rubisco, complex of Rubisco and Rubisco acitivase, spectral characteristics.

A new heuristic algorithm for the circular packing problem with equilibrium constraints

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Science china(Information Sciences) 2011年第8期54卷 1572-1584页

作者： LIU JingFa 1,2,LI Gang 3.& GENG HuanTong 1 1 school of Computer and Software,Nanjing university of Information Science & Technology,Nanjing 210044,china 2 Network Information Center,Nanjing university of Information Science & Technology, Nanjing 210044,china 3.school of Mathematics and physics,Nanjing university of Information Science & Technology,Nanjing 210044,china school of Computer and Software Nanjing University of Information Science & Technology Nanjing China Network Information Center Nanjing University of Information Science & Technology Nanjing China school of Mathematics and physics Nanjing University of Information Science & Technology Nanjing China

The circular packing problem with equilibrium constraints is an optimization problem about simplified satellite module layout design.A heuristic algorithm based on tabu search is put forward for solving this *** algorithm begins from a random initial configuration and applies the gradient method with an adaptive step length to search for the minimum energy *** jump out of the local minima and avoid the search doing repeated work,the algorithm adopts the strategy of tabu *** the process of tabu search,we improve the traditional neighboring solutions,tabu objects and the acceptance criteria of the current solution *** test two sets of benchmarks consisting of 11 representative instances from the current *** numerical results show that the proposed algorithm breaks the records in seven out of 11 instances,and obtains the optimal solutions for the other four instances.

关键词： equilibrium constraints packing problem heuristic algorithm tabu search layout optimization

Current distribution and stability of LTS/HTS hybrid superconducting conductors

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Science china(Technological Sciences) 2010年第7期53卷 2000-2007页

作者： GUAN XiaoJin1,2, WANG YinShun1 & ZHOU WeiWei3.1 Key Laboratory of HV and EMC Beijing, North china Electric Power university, Beijing 102206, china 2 Department of {3., Baoding university, Baoding 071000, china 3.Institute of Electrical engineering, Chinese Academy of Sciences, Beijing 100190, china Key Laboratory of HV and EMC Beijing North China Electric Power University Beijing China Department of physics Baoding University Baoding China Institute of Electrical engineering Chinese Academy of Sciences Beijing China

Current distribution and stability of a hybrid LTS/HTS superconductor, consisting of multifilamentary NbTi/Cu and Bi2223.Ag tapes, were numerically analyzed according to power-law models. The results showed that most of current passed through the LTS and the current increased in the HTS with temperature rise when the transport current was below the critical current of the hybrid conductor. The quench propagation velocity of the hybrid conductor was smaller but its minimum quench energy was larger than those of LTS conductors, indicating that the stability of the hybrid superconducting conductor was effectively improved and a high engineering current density was simultaneously achieved. Finally, a hybrid sample, made by soldering Bi2223.Ag tape onto NbTi/Cu conductor, was prepared and tested successfully at helium temperature. The experimental results qualitatively agreed with the simulated ones.

关键词： distribution hybrid conductor minimum quench energy quench propagation velocity n value stability

Characterization of microarc oxidation coatings on pure titanium

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Rare Metals 2003年第1期22卷 42-48页

作者： XUE Wenbin, WANG Chao, Li Yongliang, and CHEN RuyiKey Laboratory for Beam Technology and Materials Modification, Institute of Low energy nuclear physics, Beijing Normal {3., Beijing 100875, china 北京师范大学射线束技术与材料改性教育部重点实验室北京 100875

Key Laboratory for Beam Technology and Materials Modification, Institute ofLow energy nuclear physics, Beijing Normal {3.The morphology, composition, and phase structure of the oxide coatings produced on the surface ofpure titanium by alternating-current microarc discharge in aluminate solution were investigated byX-ray diffraction and scanning electron microscopy. The profiles of the hardness H and the elasticmodulus E in the coatings were determined using a nanoindentation method. The concentrationdistributions of Ti, Al, and O in the coating show that this coating over 3. mu m thick contains twolayers: an outer layer and an inner layer. The oxide coating is mainly composed of TiO_2 rutile andAl_2TiO_5 compounds. During oxidation, the temperature in the microarc discharge channel was veryhigh to make the local coating molten. From the surface to the interior of the coating, H and Eincrease gradually, and then reach maximum values of 9.78 GPa and 176 GPa respectively at a distanceof 7 mu m from the coating/titanium interface. They are also rather high near the interface.

关键词： pure titanium ceramic coating microarc oxidation microstructure nanoindentation

Influence of Yb^(3.) concentration on the upconversion luminescence of oxyfluoride material doped with Er^(3.)

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Science china(physics,Mechanics & Astronomy) 2010年第2期53卷 310-314页

作者： ZHAO SuLing1,XU Zheng1,WANG LiHui2 & S. Wageh3.1 Institute of Optoelectronic Technology,Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong university),Ministry of Education,Beijing 100044,china 2 Department of physics,Chinese People’s Public Security university,Beijing 10003.,china 3.physics & engineering Mathematics Department Faculty of Electronic engineering Menufiya university,Menouf 3.952,Egypt Institute of Optoelectronic Technology Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Ministry of Education Beijing China Department of physics Chinese People’s Public Security University Beijing China physics & engineering Mathematics Department Faculty of Electronic engineering Menufiya {3. Menouf Egypt

In this paper,a new upconversion luminescent material co-doped with Erbium and Ytterbium is reported. The upconversion luminescence transition routes and related properties are studied. The results show that the absorption and emission intensities under excitation of 980 nm laser increase with the increase of the Yb3. concentration. The red emission is stronger than the green emission. The energy transfer process plays an important role in the upconversion mechanism.

关键词： upconversion luminescence Er3. Yb3.

Systematic study of survival probability of excited superheavy nuclei

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 109-113页

作者： XIA ChengJun1, SUN BaoXi1, ZHAO EnGuang2,3.& ZHOU ShanGui2,3.1College of Applied Sciences, Beijing university of Technology, Beijing 100124, china 2Institute of Theoretical physics, Chinese Academy of Sciences, Beijing 100190, china 3.enter of Theoretical nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 73.000, china College of Applied Sciences Beijing University of Technology Beijing China Institute of Theoretical physics Chinese Academy of Sciences Beijing China Center of Theoretical nuclear physics National Laboratory of Heavy Ion Accelerator Lanzhou China

The stability of excited superheavy nuclei (SHN) with 100 Z 13. against neutron emission and fission is investigated by using a statistical model. In particular, a systematic study of the survival probability against fission in the 1n-channel of these SHN is made. The present calculations consistently take the neutron separation energies and shell correction energies from the calculated results of the finite range droplet model which predicts an island of stability of SHN around Z = 115 and N = 179. It turns out that this island of stability persists for excited SHN in the sense that the calculated survival probabilities in the 1n-channel of excited SHN at the optimal excitation energy are maximized around Z = 115 and N = 179. This indicates that the survival probability in the 1n-channel is mainly determined by the nuclear shell effects.

关键词： survival probability superheavy elements island of stability neutron emission fission

|m| Partial wave treatment for two-dimensional Coulomb-scattering and Regge pole

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Science china(physics,Mechanics & Astronomy) 2004年第6期47卷 676-684页

作者： WANG Jing & ZENG Jinyan Department of physics,Tsinghua university,Beijing 100084,china {3. of physics,Peking university,Beijing 100871,china Department of physics Tsinghua University Beijing 100084 China school of physics Peking University Beijing 100871 China

The symmetry and |m| partial-wave analysis for two-dimensional (2D) Coulomb-scattering is investigated. As a function of energyE, the |m| partial-wave scattering amplitudef |m|(θ) is analytically continuated to the, negativeE (complexk) plane, and it is found that the bound state energy eigenvalues (Eenergy eigenvalues are just located at the poles off |m|(θ) on the positive real |m| axis.

关键词： two-dimensional Coulomb scattering, |m| partial-wave, Regge pole.

Main chemical ingredients of the celadon glaze from Qingliangsi kiln and Zhanggongxiang kiln

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 487-495页

作者： ZHAO Weijuan1, LU Xiaoke1, LI Guoxia1, GUO Min1, XIE Jianzhong1, GAO Zhengyao1, SUN Xinmin2, GUO Musen2, CHENG Huansheng3.& ZHANG Bin3.1. Faculty of Physical engineering, Zhengzhou university, Zhengzhou 450052, china 2. Research Institute of Cultural Relic and Archaeology, Henan Province, Zhengzhou 450004, china 3. Research Institute of Modern physics, Fudan university, Shanghai 20043., china Faculty of Physical engineering Zhengzhou University Zhengzhou China Research Institute of Cultural Relic and Archaeology Zhengzhou China Research Institute of Modern physics Fudan University Shanghai China

The proton induced X-ray emission (PIXE) is used to determine the chemical ingredients of seven main elements in the samples of Ru Guan porcelain glazes and Ru Civil porcelain from Qingliangsi kiln in Baofeng County and the samples of celadon glaze from Zhanggongxiang kiln in Ruzhou City. The PIXE data are then analyzed by scatter analysis and fuzzy cluster method for determining their classification and provenance. The results show that there are obvious differences between the ingredients of glaze material of Ru Guan porcelain and Ru Civil porcelain from Qingliangsi kiln, of which the former ingredients are stable and its source is localized, and that the sources and ingredients of the glaze of Ru Guan porcelain and those of celadon glaze from Zhanggongxiang kiln are not wholly the same, of which the latter sources are much scattering.

关键词： Zhanggongxiang kiln, Qingliangsi kiln, the source of raw material, the proton induced X-ray emission.