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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 465-468页

作者： ZHANG yuChao1, XING ZhiGang2, MA ZiGuang2, CHEN Yao2, DING Guojian2, XU PeiQiang2, dong ChenMing3, CHEN Hong2 & LE Xiaoyun1 1 School of physics and Nuclear energy Engineering, Beihang University, beijing 100190, china 2 Renewable energy Laboratory, institute of physics, chinese academy of sciences, beijing 100190, china 3 School of Information and Communication, Tianjin Polytechnic University, Tianjin 300160, china School of physics and Nuclear energy Engineering Beihang University Beijing China Renewable energy Laboratory Institute of Physics Chinese Academy of Sciences Beijing China School of Information and Communication Tianjin Polytechnic University Tianjin China

GaN epifilms are grown on the patterned sapphire substrates (PSS) (0001) and the conventional sapphire substrates (CSS) (0001) by metal-organic chemical vapor deposition (MOCVD) using a novel two-step growth. high resolution X-ray diffraction (HR-XRD) is used to investigate the threading dislocation (TD) density of the GaN epifilms. The TD density is calculated from the ω-scans full width at half maximum (FWHM) results of HR-XRD. The edge dislocation destiny of GaN grown on the PSS is 2.7×108 cm-2, which is less than on the CSS. This is confirmed by the results of atomic force microscopy (AFM) measurement. The lower TD destiny indicates that the crystalline quality of the GaN epifilms grown on the PSS is improved compared to GaN epifilms grown on the CSS. The residual strains of GaN grown on the PSS and CSS are compared by Raman Scattering spectra. It is clearly seen that the residual strain in the GaN grown on PSS is lower than on the CSS.

关键词： GaN patterned sapphire substrate threading dislocation XRD

Pd single atoms cooperate with S vacancies in ZnIn_(2)S_(4) nanosheets for photocatalytic pure-water splitting

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Science china Chemistry 2024年第3期67卷 855-861页

作者： Lin Sun Huiping Peng Fei Xue Shangheng liu Zhiwei Hu Hongbo Geng Xiaozhi liu dong Su Yong Xu Xiaoqing Huang State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Guangzhou Key Laboratory of Low-Dimensional Materials and energy Storage Devices Collaborative Innovation Center of Advanced Energy MaterialsSchool of Materials and EnergyGuangdong University of TechnologyGuangzhou 510006China Max Planck institute for Chemical physics of Solids Nothnitzer Strasse 40Dresden 01187Germany School of Materials Engineering Changshu Institute of TechnologyChangshu 215500China beijing National Laboratory for Condensed Matter physics institute of physics Chinese Academy of SciencesBeijing 100190China Innovation Laboratory for sciences and Technologies of energy Materials of Fujian Province(IKKEM) Xiamen 361005China

Photocatalytic water splitting has emerged as a new frontier for converting solar energy to green H_(2) and value-added ***,great challenges still remain for developing efficient photocatalysts for pure water splitting without sacrificial *** this work,we demonstrate that doping hexagonal ZnIn_(2)S_(4)(ZIS) with Pd single atoms(Pd_(0.03)/ZIS) can serve as a highly efficient photocatalyst for pure water splitting to simultaneously produce H_(2) and H_(2)O_(2) without any sacrificial *** from aberration-corrected high-angle annular dark field scanning transmission electron microscopy,X-ray fine spectroscopy,insitu electron paramagnetic resonance and diffuse Fourier transform infrared spectroscopy reveal that doping ZIS with Pd single atoms facilitates the formation of S vacancies(S_(v)),where the photogenerated electrons can transfer to Pd single atoms,as a result of enhanced separation of electron-hole pairs and improved photocatalytic ***,Pd_(0.03)/ZIS displays a stoichiometric ratio of H_(2) and H_(2)O_(2) with the productivity of 1,037.9 and 1,021.4μmol g^(-1)h^(-1),respectively,which has largely outperformed pure ZIS and other reported catalysts for pure water *** work provides an efficient photocatalyst for water splitting to produce H_(2) and H_(2)O_(2),which may attract rapid interest in materials science,chemistry,and heterogeneous catalysis.

关键词： ZnIn_(2)S_(4) Pd single atom S vacancy pure water splitting H_(2)O_(2)

An all-metallic nanovesicle for hydrogen oxidation

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National Science Review 2024年第6期11卷 233-242页

作者： Juntao Zhang Lujie Jin Hao Sun Xiaozhi liu yujin Ji Youyong Li Wei liu dong Su Xuerui liu Zhongbin Zhuang Zhiwei Hu Qi Shao Xiaoqing Huang State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University Innovation Laboratory for sciences and Technologies of energy Materials of Fujian Province(IKKEM) Key Laboratory for Special Functional Materials of Ministry of Education National &Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology School of Materials Science and EngineeringCollaborative Innovation Center of Nano Functional Materials and Applications Henan University institute of Functional Nano and Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials& Devices Soochow University State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied Chemistry Chinese Academy of Sciences beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences State Key Lab of Organic-Inorganic Composites Beijing University of Chemical Technology Max Planck institute for Chemical physics of Solids College of Chemistry and Chemical Engineering and Materials Science Soochow University

Vesicle, a microscopic unit that encloses a volume with an ultrathin wall, is ubiquitous in ***, it remains a huge challenge to create its inorganic metal-based artificial counterparts. Here,inspired by the formation of biological vesicles, we proposed a novel biomimetic strategy of curling the ultrathin nanosheets into nanovesicles, which was driven by the interfacial strain. Trapped by the interfacial strain between the initially formed substrate Rh layer and subsequently formed RhRu overlayer, the nanosheet begins to deform in order to release a certain amount of strain. Density functional theory（DFT）calculations reveal that the Ru atoms make the curling of nanosheets more favorable in thermodynamics applications. Owing to the unique vesicular structure, the RhRu nanovesicles/C displays excellent hydrogen oxidation reaction（HOR） activity and stability, which has been proven by both experiments and DFT calculations. Specifically, the HOR mass activity of RhRu nanovesicles/C are 7.52 A mg（Rh+Ru）-1at an overpotential of 50 m V at the rotating disk electrode（RDE） level; this is 24.19 times that of commercial Pt/C(0.31 m A mgPt-1). Moreover, the hydroxide exchange membrane fuel cell（HEMFC） with RhRu nanovesicles/C displays a peak power density of 1.62 W cm-2in the H2-O2condition, much better than that of commercial Pt/C(1.18 W cm-2). This work creates a new biomimetic strategy to synthesize inorganic nanomaterials, paving a pathway for designing catalytic reactors.

关键词： biomimetic synthesis nanovesicle interfacial strain hydrogen oxidation reaction

Isospin-dependent relativistic microscopic optical potential in the Dirac Brueckner-Hartree-Fock method

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 189-198页

作者： RONG jian1 & MA Zhongyu1,2,3 1. china institute of Atomic energy, beijing 102413, china 2. Center of Nuclear Theoretical physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lan-zhou 730000, china 3. institute of Theoretical physics, chinese academy of sciences, beijing 100080, china Correspondence should be addressed to Rong jian (email: jrong@***) china institute of Atomic energy Beijing China Center of Nuclear Theoretical physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China institute of Theoretical physics Chinese Academy of Sciences Beijing China

The relativistic microscopic optical potential in the asymmetric nuclear matter is studied in the framework of the Dirac Brueckner-Hartree-Fock method. A new decomposition of the Dirac structure of the nuclear self-energy in nuclear matter is adopted. The self-energy of a nucleon with E > 0 in nuclear matter is calculated with the G matrix in the Hartree-Fock approach. The optical potential of a nucleon in the nuclear medium is identified with the nucleon self-energy. The energy and asymmetric parameter dependence of the relativistic optical potentials for proton and neutron are discussed. The resulting Schroedinger equivalent potentials have reasonable behaviors of the energy dependence. The asymmetric parameter dependence of relativistic optical potentials and Schroedinger potentials are emphasized.

关键词： Dirac Brueckner Hartree-Fock, relativistic microscopic optical potential, asymmetric nuclear matter, isospin-dependence.

Implementation of a particle-in-cell method for the energy solver in 3D spherical geodynamic modeling

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Earth and Planetary physics 2024年第3期8卷 549-563页

作者： Hao dong ZeBin Cao LiJun liu YanChong Li SanZhong Li LiMing Dai Xinyu Li Frontiers Science Center for Deep Ocean Multispheres and Earth System Key Laboratory of Submarine Geosciences and Prospecting TechniquesMinistry of Education and College of Marine GeosciencesOcean University of ChinaQingdao 266100China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Laboratory for Marine Geology Laoshan LaboratoryQingdao 266237China Department of Earth Science&Environmental Change University of Illinois at Urbana-ChampaignUrbanaIL 61801USA Laboratory of Seismology and physics of Earth’s Interior School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China

The thermal evolution of the Earth’s interior and its dynamic effects are the focus of Earth ***,the commonly adopted grid-based temperature solver is usually prone to numerical oscillations,especially in the presence of sharp thermal gradients,such as when modeling subducting slabs and rising *** phenomenon prohibits the correct representation of thermal evolution and may cause incorrect implications of geodynamic *** examining several approaches for removing these numerical oscillations,we show that the Lagrangian method provides an ideal way to solve this *** this study,we propose a particle-in-cell method as a strategy for improving the solution to the energy equation and demonstrate its effectiveness in both one-dimensional and three-dimensional thermal problems,as well as in a global spherical simulation with data *** have implemented this method in the open-source finite-element code CitcomS,which features a spherical coordinate system,distributed memory parallel computing,and data assimilation algorithms.

关键词： numerical oscillation overshooting and undershooting particle-in-cell method three-dimensional spherical geodynamic modeling energy solver finite element method

In-flight energy Calibration of the GECAM Gamma-ray Detectors

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Research in Astronomy and Astrophysics 2024年第10期24卷 48-57页

作者： Rui Qiao dong-Ya Guo Wen-Xi Peng Yan-Qiu Zhang Shuo Xiao Shao-Lin Xiong Chao Zheng Chao-Yang Li Jia-Cong liu Wang-Chen Xue jian-jian He Zheng-Hua An Da-Li Zhang Xin-Qiao Li Li-Ming Song Shi-Jie Zheng Ke Gong Ya-Qing liu Xin-Ying Song Xiao-yun Zhao Xiang-Yang Wen Yan-bing Xu Xiang Ma Xiao-Bo Li Ping Wang yue Huang Ce Cai Qi-Bin Yi Yi Zhao Chen-Wei Wang institute of high energy physics Chinese Academy of SciencesBeijing 100049China University of chinese academy of sciences Beijing 100049China china West Normal University Nanchong 637002China Xiangtan University Xiangtan 411105China beijing Normal University Beijing 100875China

The Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor(GECAM)mission is designed to monitor the Gamma-Ray Bursts(GRBs)associated with gravitational waves and other high-energy transient *** mission consists of two microsatellites which are planned to operate at the opposite sides of the *** GECAM satellite could detect and localize GRBs in about 8 keV-5 MeV with its 25 Gamma-Ray Detectors(GRDs).In this work,we report the in-flight energy calibration of GRDs using the characteristic gamma-ray lines in the background spectra,and show their performance evolution during the commissioning ***,a preliminary cross-calibration of energy response with Fermi GBM data is also presented,validating the energy response of GRDs.

关键词： (stars:)gamma-ray burst:general instrumentation:detectors methods:data analysis

Simulation study of real-time monitor for BEPC-Ⅱ luminosity

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Science china(Technological sciences) 2010年第5期53卷 1215-1219页

作者： SHAN Qing1,2,WU jian2,XUE Zhen2,XU ZiZong2,HU Tao3,WANG YiFang3 & WANG XiaoLian2 1 College of Material Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,china 2 Department of Modern physics,University of Science and Technology of china,Hefei 230026,china 3 institute of high energy physics,chinese academy of sciences,beijing 100049,china College of Material Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing China Department of Modern physics University of Science and Technology of China Hefei China institute of high energy physics Chinese Academy of Sciences Beijing China

A fast and real time luminosity monitor system will be used in the BEPC-Ⅱ(beijing Electron Positron Collider,china).Photons generated in radiative Bhabha scattering at the interaction point are transformed into charged particles,and then the luminosity of each bunch pair is measured through collecting the Cherenkov light produced by charged particles in fused *** whole process happening in the detector is *** physics acceptance and detection threshold with the monitor accu-racy of 1% are set based on the simulation spectra of photoelectron yield calibrated by e-beam data.

关键词： luminosity BEPC-Ⅱ Cherenkov detector radiative Bhabha

Plutonium utilization in a small modular molten-salt reactor based on a batch fuel reprocessing scheme

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Nuclear Science and Techniques 2024年第4期35卷 15-28页

作者： Xue-Chao Zhao Rui Yan Gui-Feng Zhu Ya-Fen liu jian Guo Xiang-Zhou Cai Yang Zou Shanghai institute of Applied physics Chinese Academy of SciencesShanghai 201800China CAS Innovative Academies in TMSR energy System Chinese Academy of SciencesShanghai 201800China University of chinese academy of sciences Beijing 100049China

A molten salt reactor(MSR)has outstanding features considering the application of thorium fuel,inherent safety,sustainability,and resistance to ***,fissile material^(233)U is significantly rare at the current stage,thus it is difficult for MSR to achieve a pure thorium-uranium fuel ***,using plutonium or enriched uranium as the initial fuel for MSR is more *** this study,we aim to verify the feasibility of a small modular MSR that utilizes plutonium as the starting fuel(SM-MSR-Pu),and highlight its advantages and ***,the structural design and fuel management scheme of the SM-MSR-Pu were ***,the neutronic characteristics,such as the graphite-irradiation lifetime,burn-up performance,and coefficient of temperature reactivity were calculated to analyze the physical characteristics of the *** results indicate that plutonium is a feasible and advantageous starting fuel for a SM-MSR;however,there are certain shortcomings that need to be *** a 250 MWth SM-MSR-Pu,approximately 288.64 kg^(233)U of plutonium with a purity of greater than 90% is produced while 978.00 kg is burned every ten *** temperature reactivity coefficient decreases from -4.0 to -6.5 pcm K^(-1) over the 50-year operating time,which ensures a long-term safe ***,the amount of plutonium and accumulation of minor actinides(MAs)would increase as the burn-up time increases,and the annual production and purity of^(233)U will *** achieve an optimal burn-up performance,setting the entire operation time to 30 years is ***,more than 3600 kg of plutonium eventually accumulate in the *** research is required to effectively utilize this accumulated plutonium.

关键词： Molten salt fuel Plutonium utilization ^(233)U TRUs mole fraction Temperature feedback coefficient

Azimuthal anchoring of a nematic liquid crystal on a grooved interface with anisotropic polar anchoring

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chinese physics B 2012年第6期21卷 378-384页

作者：周璇张志东叶文江宣丽 State Key Laboratory of Applied Optics Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences Graduate School of the chinese academy of sciences Department of physics Hebei University of Technology

Zhang Y J et al.[Zhang Y J,Zhang Z D,Zhu L Z and Xuan L 2011 Liquid Cryst.38 355] investigated the effects of finite polar anchoring on the azimuthal anchoring energy at a grooved interface,in which polar anchoring was isotropic in the local tangent plane of the *** this paper,we investigate the effects of both isotropic and anisotropic polar anchoring on the surface anchoring energy in the frame of Fukuda et al.’s *** results show that anisotropic polar anchoring strengthens the azimuthal anchoring of grooved *** the one-elastic-constant approximation（K11 = K22 = K33 = K）,the surface-groove-induced azimuthal anchoring energy is entirely consistent with the result of Faetti,and it reduces to the original result of Berreman with an increase in polar ***,the contribution of the surface-like elastic term to the Rapini-Papoular anchoring energy is zero.

关键词： azimuthal anchoring energy surface grooves anchoring isotropy anchoring anisotropy

Microstructure in Ni80 Fe20/Cu magneticmultilayers and spin valve

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电子显微学报 2000年第1期 17-25页

作者： WANG Wen\|dong\ SUN Hai\|ping\ ZHANG Ze (beijing Laboratory of Electron Microscopy,institute of physics,chinese academy of sciences,beijing,100080,P.R.china)

用高分辨电子显微学及平行电子能量损失谱方法研究了Ni80Fe20Cu基磁性多层膜和自旋阀的显微结构。高分辨像显示,磁性多层膜及自旋阀均具有沿薄膜生长方向的柱晶结构。Ni,Fe,Cu和Mn元素的成分分布图显示,柱晶内仍保持完整的层状结构。沿... 详细信息

用高分辨电子显微学及平行电子能量损失谱方法研究了Ni80Fe20Cu基磁性多层膜和自旋阀的显微结构。高分辨像显示,磁性多层膜及自旋阀均具有沿薄膜生长方向的柱晶结构。Ni,Fe,Cu和Mn元素的成分分布图显示,柱晶内仍保持完整的层状结构。沿薄膜生长方向的自旋阀元素分布曲线分析表明,NiFe层中的Ni元素沿柱晶晶界向相邻Cu层扩散。讨论了这些低维磁电子学材料的显微结构对磁输运性能的影响。

关键词： Fe 磁性多层膜显微结构柱晶薄膜生长晶体生长高分辨电子显微学自旋阀 Cu magneticmultilayers and spin valve