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Optoelectronics Letters 2023年第1期19卷 31-35页

作者： Ibtisam F Al Maaitah Applied Physics Department Faculty of ScienceTafila Technical UniversityP.O.Box 179TafilaJordan

We report a theoretical analysis of the electronic,optical,and mechanical properties of zinc-blende Ga P semiconductor material.High-temperature impact on the interesting features has been reported.The temperature dependence of sound velocity and phonon frequencies of Ga P has been determined.The pseudopotential technique has been used in our study.The current study can help in our comprehension of how temperature affects the electronic characteristics of Ga P material.Our findings show generally a good accordance with the experiment.The prediction properties could be used in optoelectronic applications in the high-temperature range.

关键词： material electronic characteristics

Modification of diphenylamine-linked bis(oxazoline) ligands: Tuning of electronic effect and rigidity of ligand skeleton

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Science China Chemistry 2009年第9期52卷 1321-1330页

作者： LIU Han LI Wei DU DaMing Beijing National Laboratory for Molecular Sciences(BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China School of Chemical Engineering and Environment Beijing Institute of TechnologyBeijing 100081China

The electronic effect of diphenylamine-linked bis(oxazoline) ligands was tuned through introduction of electron-withdrawing bromo and nitro substituents onto the 4 and 4′ position. The variation of the NH bond acidity was determined by the different chemical shifts of NH. The catalytic activity and enantioselectivity of the modified ligands were tested in the asymmetric Friedel-Crafts alkylation of indole with β-nitrostyrene. The effect of ligand skeleton rigidity was also investigated through the synthesis of iminodibenzyl-linked bis(oxazoline) ligands and evaluation of their catalytic activity in Friedel-Crafts alkylation.

关键词： asymmetric catalysis electronic effect bis(oxazoline) Friedel-Crafts alkylation

Time-dependent density-functional theory for open electronic systems

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Science China Chemistry 2014年第1期57卷 26-35页

作者： ZHENG Xiao WANG RuLin Hefei National Laboratory for Physical Sciences at the Microscale University of Science and Technology of China Department of Physics University of Science and Technology of China

Time-dependent density-functional theory(TDDFT)has been successfully applied to predict excited-state properties of isolated and periodic systems.However,it cannot address a system coupled to an environment or whose number of electrons is not conserved.To tackle these problems,TDDFT needs to be extended to accommodate open systems.This paper provides a comprehensive account of the recent developments of TDDFT for open systems(TDDFT-OS),including both theoretical and practical aspects.The practicality and accuracy of a latest TDDFT-OS method is demonstrated with two numerical examples:the time-dependent electron transport through a series of quasi-one-dimensional atomic chains,and the real-time electronic dynamics on a two-dimensional graphene surface.The advancement of TDDFT-OS may lead to promising applications in various fields of chemistry,including energy conversion and heterogeneous catalysis.

关键词： time-dependent density functional theory,real-time electronic dynamics,hierarchical equations of motion

Magnetic-field modulation of topological electronic state and emergent magneto-transport in a magnetic Weyl semimetal

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The Innovation 2023年第2期4卷 78-82,77页

作者： Jianlei Shen Jiacheng Gao Changjiang Yi Meng Li Shen Zhang Jinying Yang Binbin Wang Min Zhou Rongjin Huang Hongxiang Wei Haitao Yang Youguo Shi Xiaohong Xu Hong-Jun Gao Baogen Shen Geng Li Zhijun Wang Enke Liu Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education&Research Institute of Materials Science Shanxi Normal UniversityTaiyuan 030000China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China Ningbo Institute of Materials Technology&Engineering Chinese Academy of SciencesNingboZhejiang 315201China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhouJiangxi 341000China

The modulation of topological electronic state by an external magnetic field is highly desired for condensed-matter physics.Schemes to achieve this have been proposed theoretically,but few can be realized experimentally.Here,combining transverse transport,theoretical calculations,and scanning tunneling microscopy/spectroscopy(STM/S)investigations,we provide an observation that the topological electronic state,accompanied by an emergent magneto-transport phenomenon,was modulated by applying magnetic field through induced non-collinear magnetism in the magnetic Weyl semimetal EuB6.A giant unconventional anomalous Hall effect(UAHE)is found during the magnetization re-orientation from easy axes to hard ones in magnetic field,with a UAHE peak around the low field of 5 kOe.

关键词： topological electronic state

Evolution Characteristics of Government-Industry-University Cooperative Innovation Network of electronic Information Industry in Liaoning Province, China

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Chinese Geographical Science 2019年第3期29卷 528-540页

作者： PENG Fei ZHANG Qiqi HAN Zenglin DING Yan FU Ningning Research Center for Marine Economy and Sustainable Development Liaoning Normal University College of Urban and Environmental Science Liaoning Normal University

It is important to optimize the cooperative innovation network for the improvement of economic competence and innovative power. Based on the patent information services platform, we obtain invention patent data for the electronic information industry in Liaoning from 1985 to 2015. This paper analyzes the cooperative innovation network structure, its spatiotemporal evolution and the triple helix relationship of government-industry-university(GIU) by using the social network analysis method and the triple helix theory as well as UCINet, ArcGIS and NetDraw. The empirical results show that: 1) the number of the subjects of the electronic information industry GIU cooperative innovation network in Liaoning demonstrates a gradual increase from 1985 to 2015, with the same trend in concentration. In terms of its subject and its centrality, the universities have a higher position, and the industries have a lower position,while the status of the government is still unclear. 2) The cooperative innovation network presents a core-periphery structure, and the polarization effect of innovation subjects tends to be obvious. There is certain distance-decay regularity in the cooperative innovation network, and a strong geographical proximity to cooperative innovation. 3) The compactness shows a downward trend as a whole. In terms of the extent of participation, the industries are better than the government but worse than the universities. This means that the cooperative innovation network of GIU in the electronic information industry in Liaoning is in the initial stage of formation.

关键词： government-industry-university (GIU) cooperative innovation network triple helix electronic information industry Liaoning Province

The electronic structure and grain boundary segregation by boron addition——A binding energy shifting criterion for the brittle-ductile fracture transition in Ni_3Al

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Science China(Technological Sciences) 1997年第2期40卷 184-191页

作者：张云林栋梁 Department of Materials Science Shanghai Jiaotong University Shanghai 200030 China

The electronic structure and grain boundary segregation caused by boron addition to Ni3Al have been studied by X-ray photoelectron spectroscopy and Auger electron spectroscopy, respectively. The obtained results show that the Ni2p3/2 electron binding energy rises gradually in the sequence of pure Ni0, the brittle failure occurs in Ni3Al; when ΔEB<0, the ductile

关键词： intermetallic Ni3Al boron electronic structure grain boundary segregation brittle-ductile fracture transition.

Mechanical Properties and electronic Structure of N and Ta Doped TiC: A First-Principles Study

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Communications in Theoretical Physics 2014年第12期61卷 895-902页

作者：马世卿刘颖叶金文王斌 School of Materials Science and Engineering Sichuan University Key Laboratory of Advanced Special Material & Technology Ministry of Education Physics and electronic Engineering Department Xinxiang University

The first principles calculations based on density functional theory(DFT) are employed to investigate the mechanical properties and electronic structure of N and Ta doped Ti C. The result shows that the co-doping of nitrogen and tantalum dilates the lattice constant and improves the stability of Ti C. Nitrogen and tantalum can significantly enhance the elastic constants and elastic moduli of Ti C. The results of B/G and C12-C44 indicate tantalum can markedly increase the ductility of Ti C. The electronic structure is calculated to describe the bonding characteristic, which revealed the strong hybridization between C-p and Ta-d and between N-p and Ti-d. The hardnessis is estimated by a semiempirical model that is based on the Mulliken overlap population and bond length. While the weakest bond takes determinative role of the hardness of materials, the addition of Ta sharply reduces the hardness of Ti C.

关键词： density functional theory elastic properties electronic structure hardness Ti-Ta-C-N quaternary alloy

Local electronic structure and magnetic properties of 3d transition metal doped GaAs

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Science China(Physics,Mechanics & Astronomy) 2008年第5期51卷 470-480页

作者： LIN He1 & DUAN HaiMing21 Department of Chemistry,Institute of Applied Chemistry,Xinjiang University,Urumqi 830046,China 2Department of Physics,Xinjiang University,Urumqi 830046,China Department of Chemistry Institute of Applied Chemistry Xinjiang University Urumqi China Department of Physics Xinjiang University Urumqi China

The local electronic structure and magnetic properties of GaAs doped with 3 transition metal(Sc,Ti,V,Cr,Mn,Fe,Co,Ni) were studied by using discrete varia tional method(DVM) based on density functional theory.The calculated result in dicated that the magnetic moment of transition metal increases first and then de creases,and reaches the maximum value when Mn is doped into GaAs.In the cas of Mn concentration of 1.4%,the magnetic moment of Mn is in good agreement wit the experimental result.The coupling between impure atoms in the system with tw impure atoms was found to have obvious variation.For different transition meta the coupling between the impure atom and the nearest neighbor As also has dif ferent variation.

关键词： diluted magnetic semiconductor density functional theory 3d transition metal cluster model electronic structure

Imaging through flesh tissue using fs electronic holographic gating method

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Science China Mathematics 1999年第8期42卷 852-858页

作者：侯比学陈国夫郝志琦丰善王淑岩王屹山王国志 State Key Laboratory of Transient Optics Technology Xi’an Institute of Optics and Precision Mechanics Xi’an China

The experimental results of imaging through flesh tissue using fs electronic holographic gating method is reported. In the experiment, Ti: sapphire mode-locked laser is used as light source, of which the repetition rate is 100 MHz, central wavelength 800 mn, duration of pulse 20 fs, output power 80 mW. Tissue is a 7 mm thick chicken slice, and the imaged object is a metal wire with diameter of 0.5 mm. A general CCD is used to record holograms and a clear image of metal wire is obtained. Several relevant problems are discussed.

关键词： electronic holography gating flesh tissue imaging.

The equivalent potential of water molecules for electronic structure of lysine

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Science China(Physics,Mechanics & Astronomy) 2007年第1期50卷 15-30页

作者： LI ChunJie ZHENG HaoPing WANG XueMei Pohl Institute of Solid State Physics Tongji UniversityShanghai 200092China

In order to get more reliable electronic structures of proteins in aqueous solution, it is necessary to construct a potential of water molecules for protein’s electronic structure calculation. The lysine is a hydrophilic amino acid. It is positively charged (Lys+) in neutral water solution. The first-principles, all-electron, ab initio calcula-tions, based on the density functional theory, have been performed to construct such an equivalent potential of water molecules for lysine (Lys+). The process consists of three parts. First, the electronic structure of the cluster containing Lys+ and water molecules is calculated. By adjusting the positions of water molecules, the geometric structure of the cluster having minimum total energy is determined. Then, based on the structure, the electronic structure of Lys+ with the potential of water molecules is calculated using the self-consistent cluster-embedding (SCCE) method. Finally, the electronic structure of Lys+ with the potential of dipoles is calculated. The dipoles are adjusted so that the electronic structure of Lys+ with the potential of dipoles is close to that of water molecules. Thus the equivalent potential of water molecules for the electronic structure of lysine is obtained. The major effect of water molecules on lysine’s electronic structure is raising the occupied eigenvalues about 0.5032 eV, and broadening energy gap 89%. The effect of water molecules on the electronic structure of lysine can be simulated by dipoles potential.

关键词： lysine electronic structure water molecule free cluster calculation self-consistent cluster-embedding calculation