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atomic Coherence in the Micromaser Injected with Slow V-type Three-State Atoms: Emission Probability

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Chinese Physics Letters 2001年第2期18卷 223-224页

作者： ZHANG Zhi-Ming LIANG Wen-Qing XIE Sheng-Wu Department of Applied Physics Shanghai Jiao Tong UniversityShanghai 200030

The effects of atomic coherence on the single-mode two-photon micromaser injected with slow V-type three-state atoms are studied for the first *** is shown that the atomic coherence can modify the atomic emission *** ... 详细信息

关键词： probability Probability atomic

atomic Layer Deposition-Assisted Construction of Binder-Free Ni@N-Doped Carbon Nanospheres Films as Advanced Host for Sulfur Cathode

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Nano-Micro Letters 2019年第4期11卷 147-160页

作者： Jun Liu Aixiang Wei Guoxiang Pan Qinqin Xiong Fang Chen Shenghui Shen Xinhui Xia Guangdong Provincial Key Laboratory of Functional Soft Condensed Matter School of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006People’s Republic of China Department of Information Science Xinhua College of Sun Yat-sen UniversityGuangzhou 510520People’s Republic of China Department of Materials Chemistry Huzhou UniversityHuzhou 313000People’s Republic of China College of Materials and Environmental Engineering Hangzhou Dianzi UniversityHangzhou 310018People’s Republic of China Department of Chemistry Zhejiang UniversityHangzhou 310027People’s Republic of China State Key Laboratory of Silicon Materials Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Provinceand Department of Materials Science and EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin 300071People’s Republic of China

Rational design of hybrid carbon host with high electrical conductivity and strong adsorption toward soluble lithium polysulfides is the main challenge for achieving high-performance lithium-sulfur batteries(LSBs).Herein,novel binder-free Ni@N-doped carbon nanospheres(N-CNSs)films as sulfur host are firstly synthesized via a facile combined hydrothermal-atomic layer deposition *** cross-linked multilayer N-CNSs films can effectively enhance the electrical conductivity of electrode and provide physical blocking“dams”toward the soluble long-chain ***,the doped N heteroatoms and superficial NiO layer on Ni layer can work synergistically to suppress the shuttle of lithium polysulfides by effective chemical interaction/*** virtue of the unique composite architecture and reinforced dual physical and chemical adsorption to the soluble polysulfides,the obtained Ni@N-CNSs/S electrode is demonstrated with enhanced rate performance(816 mAh g?1 at 2 C)and excellent long cycling life(87%after 200 cycles at 0.1 C),much better than N-CNSs/S electrode and other carbon/S *** proposed design strategy offers a promising prospect for construction of advanced sulfur cathodes for applications in LSBs and other energy storage systems.

关键词： atomic layer deposition Nickel N-doped carbon nanospheres Sulfur cathode Lithium-sulfur batteries

atomic Aggregation Processes in the Early Stages of Pt/Pt(111)Growth

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Chinese Physics Letters 2000年第8期17卷 589-591页

作者： ZHUANG Guo-Ce ZHU Xiao-Bin WANG Wei National Laboratory of Solid State Microstructure and Department of Physics Nanjing UniversityNanjing 210093 Department of Physics Yancheng Teacher's CollegeYanchengJiangsu 224002

The atomic aggregation processes in the early stages of Pt/Pt(111)growth are studied by using kinetic Monte Carlo *** results show that the average neighbor coordination number of the atoms in a cluster is a function of temperature,agreeing well with the experiment observations of scanning tunneling *** influence of diffusion barriers of various atomic processes on the morphology of islands is also *** morphologies of the islands(dendritic,fractal,or compact islands)are found.

关键词： fractal atomic tunneling

atomic Structure and Doping Response of Grain Boundary in Transition Metal Ni

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Science China Mathematics 1994年第7期37卷 878-890页

作者：王崇愚于涛 International Centre for Materials Physics Academia Sinica Shenyang 110015 and Central Iron Steel Research Institute Beijing 100081 PRC Central Iron and Steel Research Institute Beijing 100081 PRC

Based on the coincidence site lattice model and by use of the molecular dynamics method, the relaxation calculations on the atomic structures of the grain boundaries of various generating functions (∑3,∑5,…, ∑19,…,∑33) in the transition metal Ni are performed. The features of atomic structures corresponding to the grain boundaries and the effects of the pre-parameter on the interface structures are given. To study the doping response relating to the properties of materials, the 23 tilt grain boundary is selected. Based on the interstice and vacancy mechanisms, the interface responses doping boron, nitrogen and phosphorus for the grain boundary are investigated. According to the criterion of the energy in molecular dynamics simulation, the most probable positions of doping impurities and effect of doping impurities on the interface structure are given, and the dependence of the fine structure on doping type and the order of the impurity amount are obtained. The analysis of the local energy for the relaxation region shows that the light impurities, boron, nitrogen and phosphorus, all have a tendency to segregate on the grain boundary and change the feature of the atomic configuration of the interface to a distinct extent. Then the effects of doping impurities on the interface can be predicted.

关键词： atomic structure of grain boundary doping response molecular dynamics method.

atomic decompositions of Banach-space-valued martingales

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Science China Mathematics 1999年第1期42卷 38-47页

作者：刘培德侯友良 1. Department of Mathematics Wuhan University 430072 Wuhan China

Several theorems for atomic decompositions of Banach-space-valued martingales are proved. As their applications, the relationship among some martingale spaces such asH α(X) andρ H α in the case 0< α? are studied. It is shown that there is a close connection between the results and the smoothness and convexity of the value spaces.

关键词： Banach-space-valued martingale martingale space atomic decomposition geometry of Banach space.

atomic states and properties of Pt-electrocatalyst

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Science China(Technological Sciences) 2006年第3期49卷 291-296页

作者： PENG Hongjian XIE Youqing College of Chemistry and Chemical Engineering College of Materials Science and Engineering Central South University Changsha 410083 China College of Chemistry and Chemical Engineering College of Materials Science and Engineering Central South University Changsha 410083 China

Using the one-atom theory (OA), the atomic state of Pt-electrocatalyst with fcc structure was determined as follows: [Xe] (5dn)6.48 (5dc)2.02 (6sc)1.48(6sf)0.02. The atomic states of this metal with hcp and bcc structures of primary characteristic crystals and liquid state was also studied. According to its atomic states, the relationship between the atomic states and crystalline structure, catalytic performance and conductivity was explained qualitatively. The potential curve, the temperature dependence of bulk modulus and linear thermal expansion coefficient of fcc-Pt were calculated quantitatively.

关键词： Pt-electrocatalyst, atomic states, crystalline structure, catalytic performance.

atomic structures of Zr-based metallic glasses

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Science China(Physics,Mechanics & Astronomy) 2008年第4期51卷 400-413页

作者： HUI XiDong LIU XiongJun GAO Rui HOU HuaiYu FANG HuaZhi LIU ZiKui CHEN GuoLiang State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Department of Materials Science and Engineering Nanjing University of Science and TechnologyNan-jing 210014China Department of Materials Science and Engineering Pennsylvania State UniversityUniversity ParkPA 16802USA

The atomic structures of Zr-Ni and Zr-Ti-Al-Cu-Ni metallic glasses were investigated by using classical molecular dynamic (MD),reverse Monte Carlo (RMC),ab initio MD (AIMD) simulations and high resolution transmission electron microscopy (HRTEM) techniques. We focused on the short-range order (SRO) and medium-range order (MRO) in the glassy structure. It is shown that there are icosahedral,FCC-and BCC-type SROs in the Zr-based metallic glasses. A structural model,characterized by imperfect ordered packing (IOP),was proposed based on the MD simulation and confirmed by the HRTEM observation. Furthermore,the evolution from IOP to nanocrystal during the crystallization of metallic glasses was also ex-plored. It is found that the growth from IOP to nanocrystal proceeds through three distinct stages: the formation of quasi-ordered structure with one-dimensional (1D) periodicity,then 2D periodicity,and finally the formation of 3D nanocrystals. It is also noted that these three growth steps are crosslinked.

关键词： metallic glasses atomic structure short-range order medium-range order molecular dynamics reverse Monte Carlo

atomic force microscopy study of the rabbit skeletal muscle ryanodine receptors in different functional states

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Science China(Life Sciences) 2002年第3期45卷 225-236页

作者：魏青青程晓阳陈克樱胡钧李民乾朱培闳 Laboratory of Neurobiology Shanghai Institute of Physiology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China Laboratory of Nuclear Analysis Shanghai Institute of Nucleus Chinese Academy of Sciences Shanghai 200800 China

atomic force microscope was applied to investigate the effect of extrinsic phospholipid on the structure of rabbit skeletal muscle ryanodine receptor/calcium release channel (RyR1). In addition, in the presence of extrinsic phospholipid, the height and elasticity of the RyR1s in different functional states were also measured. The results indicate: (i) most of the RyR1s showed a normal structure only in the presence of extrinsic phospholipid; (ii) treatment of the RyR1s with AMP and Ca2+ together could increase their Young's Modulus but not change their apparent height; (iii) no detectable change in either height or Young's Modulus of the RyR1s appeared, if the RyR1s were treated with other activators or inhibitors.

关键词： ryanodine receptor/calcium release channel, atomic force microscope, elasticity.

A descriptor of “material genes”: Effective atomic size in structural unit of ionic crystals

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Science China(Technological Sciences) 2019年第5期62卷 849-855页

作者： CHEN Dong LI ShunNing JIE JianShu LI SiBai ZHENG ShiSheng WENG MouYi YU ChangCheng LI ShuCheng CHEN DaJun PAN Feng School of Advanced Materials Shenzhen Graduate School Peking University

The atomic size of each element, described by the ionic radius, is one category of "material genes" and can facilitate our understanding of atomic arrangements in compounds. Most of the ionic radii currently used to measure the sizes of cations and anions in ionic crystals are derived from hard-sphere model based on the coordination numbers, or the soft-sphere model incorporating the effect of ionic polarization. Herein we take a first step towards a novel "effective atomic size"(EAS) model,which takes into consideration the impact of the types and number of neighboring atoms on the relationship between ionic radii and interatomic distances. Taking the binary compounds between Group IA/IIA and VIA/VIIA elements gathered from the latest databases as an example, we show that the proposed EAS model can yield excellent agreement between the predicted and the DFT-calculated interatomic distances, with deviation of less than 0.1 ?. A set of EAS radii for ionic crystals has been compiled and the role of coordination numbers, geometric symmetry and distortion of structural units has been examined. Thanks to its superior predictability, the EAS model can serve as a foundation to analyze the structure of newly-discovered compounds and to accelerate materials screening processes in the future works.

关键词： ionic radii interatomic distance effective atomic size coordination environment structural units