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Lowest-energy moiré band formed by Dirac zero modes in twisted bilayer graphene

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Science Bulletin 2019年第8期64卷 495-498页

作者： Long Zhang Kavli Institute for Theoretical Sciences and CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Physical Science Laboratory Huairou National Comprehensive Science Center

The recent discovery of an unconventional insulating phase and an adjacent superconducting (SC) phase in the twisted bilayer graphene (TBG)[1,2] has triggered great excitement (3–11)The two layers of graphene are rot... 详细信息

关键词： band formed by Dirac zero modes in twisted bilayer graphene Lowest-energy moir

CHARACTERISTICS　OF　COAL－formed　GAS　ACCUMULATION　BELTS　IN　THE　EAST　PART　OF　THE　CENTRAL－ASIA　COAL－formed　GAS　ACCUMULATION　DOMAIN　──SERIES　STUDY　Ⅲ　ON　THE　CENTRAL－ASIA　COAL－formed　GAS　ACCUMULATION　DOMAIN

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石油勘探与开发 1995年第5期22卷 87-95页

作者： Dai Jin-xing Li Xian-qi(Research Institute of Petroleum Exploration and Development, CNPC. Beijing, 100083, P. R. China)

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ＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＯＦＣＯＡＬ－ＦＯＲＭＥＤＧＡＳＡＣＣＵＭＵＬＡＴＩＯＮＢＥＬＴＳＩＮＴＨＥＥＡＳＴＰＡＲＴＯＦＴＨＥＣＥＮＴＲＡＬ－ＡＳＩＡＣＯＡＬ－ＦＯＲＭＥＤＧＡＳＡＣＣＵＭＵＬＡＴＩＯＮＤＯＭＡＩＮ──ＳＥＲＩＥＳＳＴＵＤＹⅢＯ...

关键词： GAS formed COAL ACCUMULATION BELTS ASIA EAST

Geochemistry of the high-Mg andesites at Zhangwu, western Liaoning: Implication for delamination of newly formed lower crust

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Science China Earth Sciences 2007年第12期50卷 1773-1786页

作者： HUANG Hua1,GAO Shan1,2,HU ZhaoChu1,LIU XiaoMing2 & YUAN HongLing2 1 State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China 2 State Key Laboratory of Continental Dynamics,Department of Geology,Northwest University,Xi’an 710069,China 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 2. State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China

Ten volcanic samples at Zhangwu,western Liaoning Province,North China were selected for a sys-tematic geochemical,mineralogical and geochronological study,which provides an opportunity to ex-plore the interaction between the continental crust and mantle beneath the north margin of the North China *** one basalt sample(SiO2= 50.23%),the other nine samples are andesitic with SiO2 contents ranging from 53% to 59%.They have relatively high MgO(3.4%―6.1%,Mg#=50―64) and Ni and Cr contents(Ni 27×10?6―197×10?6,Cr 51×10?6―478×10?6).Other geochemical characteristics of Zhangwu high-Mg andesites(HMAs) include strong fractionation of light rare earth elements(LREE) from heavy rare earth elements(HREE),and Sr from Y,with La/Yb greater than 15,and high Sr/Y(34― 115).Zircons of andesite YX270 yield three age groups with no Precambrian age,which precludes ori-gin of the Zhangwu HMAs from the partial melting of the Precambrian *** oldest age group peaking at 253 Ma is interpreted to represent the collision of the Siberia block and the North China block,resulting in formation of the Central Asian orogenic belt by closure of the Mongol-Okhotsk *** intermediate age group corresponds to the basalt underplating which caused the wide-spread coeval granitoids in the North China craton with a peak 206Pb/238U age of 172 *** youngest age group gives a 206Pb/238U age of 126±2 Ma,which is interpreted as the eruption age of the Zhangwu *** high 87Sr/86Sri(126 Ma)>0.706 and low εNd(t)= ?6.36―?13.99 of the Zhangwu HMAs are distinct from slab *** common presence of reversely zoned clinopyroxene phenocrysts in the Zhangwu HMAs argues against the origin of the Zhangwu HMAs either from melting of the water saturated mantle or melting of the lower *** light of the evidence mentioned above,the envisaged scenario for the formation of the Zhangwu HMAs is related to the basaltic underplating at the base of the crust,which led to the thickening of the lower crust and

关键词： Zhangwu HMAs, basalt underplating, newly formed lower crust, delamination, North China craton

The Blade of a Sword is formed by Grinding

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大学英语 1999年第3期 53-53页

作者：廖由信

ＩｗａｓｂｏｒｎｉｎａｐｏｏｒｆａｍｉｌｙｉｎａｒｅｍｏｔｅｍｏｕｎｔａｉｎｏｕｓｄｉｓｔｒｉｃｔｉｎＨｕｎａｎＰｒｏｖｉｎｃｅ．Ｉｈａｖｅ，ｆｒｏｍｍｙｃｈｉｌｄｈｏｏｄ，ｅｘｐｅｒｉｅｎｃｅｄａｎｄｒｅａｌｉｚｅ... 详细信息

ＩｗａｓｂｏｒｎｉｎａｐｏｏｒｆａｍｉｌｙｉｎａｒｅｍｏｔｅｍｏｕｎｔａｉｎｏｕｓｄｉｓｔｒｉｃｔｉｎＨｕｎａｎＰｒｏｖｉｎｃｅ．Ｉｈａｖｅ，ｆｒｏｍｍｙｃｈｉｌｄｈｏｏｄ，ｅｘｐｅｒｉｅｎｃｅｄａｎｄｒｅａｌｉｚｅｄｈｏｗｈａｒｄｌｉｆｅｉｓ．Ｈｏ...

关键词：特困生 Blade formed Grinding Sword The

Analysis of the mass of behind-armor debris generated by RHA subjected to normal penetration of variable cross-section EFP

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Defence Technology（防务技术） 2019年第3期15卷 390-397页

作者： Boyang Xing Dongjiang Zhang Zhenyan Guo Yunhui Hou Rui Guo Rongzhong Liu Liang Chen Hao Zhou Yongliang Yang Jianhua Luo School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 Jiangsu China Xi'an Modern Control Technology Research Institute Xi'an 710065 Shanxi China School of Electronic and Optical Engineering Nanjing University of Science and Technology Nanjing 210094 China

Analyzing the mass of behind-armor debris (BAD) generated by Rolled Homogeneous Armor (RHA) subjected to normal penetration of variable cross-section Explosively formed Projectile (EFP) is the purpose of this paper. So theoretical analysis, numerical simulation and experimental data are combined to analyze the influence of variable cross-section characteristic on the time history of crater radius. Moreover the relationships between time history of crater radius (as well as mass of BAD) and the thickness of RHA (from 30mm to 70 mm) and the impact velocity of EFP (1650 m/s to 1860 m/s) are also investigated. The results indicate that: 1) being compared to the variable cross-section characteristic is ignored, the theoretical time history of crater radius is in better agreement with the simulation results when the variable cross-section characteristic is considered;2) being compared to the other three conditions of plug, the theoretical mass of BAD is in the best agreement with the simulation results when the shape of plug is frustum of a cone and the angle between generatrix and bottom is 45- and the axial length of mushroom is considered.

关键词： Explosively formed projectile Behind-armor debris Variable cross-section characteristic Shape of plug Axial length of mushroom Theoretical model

Graphene oxide effects on the properties of Al2O3-Cu/35W5Cr composite

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Journal of Materials Science & Technology 2020年第2期37卷 185-199页

作者： Xiaohui Zhang Yi Zhang Baohong Tian Yanlin Jia Ming Fu Yong Liu Kexing Song AlexAVolinsky Xiao Yang Hang Sun School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China Collaborative Innovation Center of Nonferrous Metals Henan ProvinceLuoyang 471023China Henan Key Laboratory of Nonferrous Materials Science and Processing Technology Luoyang 471023China College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China China Airborne Missile Academy Luoyang 471023China Department of Mechanical Engineering University of South FloridaTampa 33620USA Luoyang Ship Material Research Institute Luoyang 471023China

Graphene oxide(GO)nanosheets were dispersed into premixed powders(Cu-0.4 wt%Al/35W5Cr)by wet grinding and vacuum freeze-drying *** 0.3 wt%GO/Al2O3-Cu/35W5Cr and 0.5 wt%GO/Al2O3-Cu/35W5Cr composites,used for electrical contacts,were fabricated by vacuum hot-pressing *** microstructure was analyzed by field emission scanning electron and transmission electron *** addition,the Raman spectroscopy and X-ray photoelectron spectroscopy were used to investigate the structural changes of GO before and after *** arc erosion behavior was investigated by the JF04 C electrical contact testing ***,the Al2O3 nanoparticles were evenly dispersed in the matrix,causing dislocation *** was converted to reduced graphene oxide after sintering.A group of carbon atoms combined with Cr forming Cr3C2 in situ during sintering,which enhanced the interface *** with the Al2O3-Cu/35W5Cr composite,the tensile strength of the two contact materials containing 0.3 wt%GO and 0.5 wt%GO was increased by 45%and 34%,***,pips and craters were present on the anode and cathode surfaces,*** has undergone re-sintering during arcing and formed needle-like *** with Al2O3-Cu/35W5Cr,the GO/Al2O3-Cu35W5Cr composites have better welding *** final mass transfer direction of the two composites was from the cathode to anode.

关键词： Graphene oxide Freeze-drying Electrical contact In situ formed Cr3C2 Tensile strength

In situ atomic-scale observation of size-dependent (de) potassiation and reversible phase transformation in tetragonal FeSe anodes

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InfoMat 2023年第1期5卷 161-171页

作者： Ran Cai Lixia Bao Wenqi Zhang Weiwei Xia Chunhao Sun Weikang Dong Xiaoxue Chang Ze Hua Ruiwen Shao Toshio Fukuda Zhefei Sun Haodong Liu Qiaobao Zhang Feng Xu Lixin Dong Beijing Advanced Innovation Center for Intelligent Robots and Systems School of Medical TechnologyBeijing Institute of TechnologyBeijingPeople's Republic of China Analysis&Testing Center Beijing Institute of TechnologyBeijingPeople's Republic of China Department of Biomedical Engineering City University of Hong KongHong KongPeople's Republic of China Shaanxi Materials Analysis and Research Center School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi'anPeople's Republic of China School of Environmental and Safety Engineering North University of ChinaTaiyuanPeople's Republic of China Department of Materials Science and Engineering College of MaterialsXiamen UniversityXiamenFujianPeople's Republic of China Department of Nanoengineering University of California San DiegoLa JollaCaliforniaUSA SEU-FEI Nano-Pico Center Key Laboratory of MEMS of Ministry of EducationSoutheast UniversityNanjingPeople's Republic of China

Potassium-ion batteries(PIBs)are considered promising alternatives to lithium-ion batteries owing to cost-effective potassium resources and a suitable redox potential of-2.93 V(vs.-3.04 V for Li+/Li).However,the exploration of appro-priate electrode materials with the correct size for reversibly accommodating large K+ions presents a significant *** addition,the reaction mecha-nisms and origins of enhanced performance remain ***,tetragonal FeSe nanoflakes of different sizes are designed to serve as an anode for PIBs,and their live and atomic-scale potassiation/depotassiation mechanisms are revealed for the first time through in situ high-resolution transmission electron *** found that FeSe undergoes two distinct structural evolutions,sequen-tially characterized by intercalation and conversion reactions,and the initial intercalation behavior is *** expansion induced by the intercalation of K+ions is observed in small-sized FeSe nanoflakes,whereas unexpected cracks are formed along the direction of ionic diffusion in large-sized *** significant stress generation and crack extension originating from the combined effect of mechanical and electrochemical interactions are elucidated by geometric phase analysis and finite-element *** the different intercalation behaviors,the formed products of Fe and K_(2)Se after full potassiation can be converted back into the original FeSe phase upon *** particular,small-sized nanoflakes exhibit better cycling perfor-mance with well-maintained structural *** article presents the first successful demonstration of atomic-scale visualization that can reveal size-dependent potassiation ***,it provides valuable guidelines for optimizing the dimensions of electrode materials for advanced PIBs.

关键词： elucidated by geometric phase analysis and finite-element analysis. Despite the different intercalation behaviors the formed products of Fe and K 2 Se after full potassiation can be converted back into the original FeSe phase upon depotassiation. In particular small-sized nanoflakes exhibit better cycling perfor- mance with well-maintained structural integrity. This article presents the first successful demonstration of atomic-scale visualization that can reveal size- dependent potassiation dynamics. Moreover it provides valuable guidelines for optimizing the dimensions of electrode materials for advanced PIBs. KEYWOR DS in situ transmission electron microscopy potassium-ion batteries potassium-ion storage mechanism size-dependent effects tetragonal FeSe

Exchange Splitting and Insulating Gap in La_(2)CuO_(4)

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Chinese Physics Letters 1999年第3期16卷 202-204页

作者： WU Hua ZHENG Qing-qi Institute of Solid State Physics Chinese Academy of SciencesHefei 230031 Hefei Institute for Advanced Study University of Science and Technology of ChinaHefei 230026 State Key Laboratory for Magnetism Chinese Academy of SciencesBeijing 100080

A full-potential band calculation for La_(2)CuO_(4) is performed within the local-spin-density *** is shown that the strongly orbital-dependent exchange splittings due to the anisotropic exchange potential induce an a... 详细信息

关键词： (4) exchange formed

Light-driven high-precision cell adhesion kinetics

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Light(Science & Applications) 2022年第10期11卷 2256-2257页

作者： Zhiyuan Zhang Daniel Ahmed Acoustic Robotics Systems Laboratory Institute of Robotics and Intelligent SystemsDepartment of Mechanical and Process EngineeringETH ZurichS?umerstrasse 4CH-8803 ZurichSwitzerland

Existing single-cell adhesion kinetics methods are performed under conditions highly unlike the physiological cell adhesion ***,researchers have developed a new optical technique for high-precision measurement of cell... 详细信息

关键词： conditions. kinetics formed