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Full Torus Electromagnetic Gyrokinetic Particle Simulations with Kinetic Electrons

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Communications in Computational Physics 2009年第1期5卷 183-194页

作者： Y.Nishimura Z.lin l.chen Department of Physics and Astronomy University of CaliforniaIrvine92697-4575USA

The full torus electromagnetic gyrokinetic particle simulations using the hybrid model with kinetic electrons in the presence of magnetic shear is *** fluid-kinetic electron hybrid model employed in this paper improves numerical properties by removing the tearing mode,meanwhile,preserves both linear and nonlinear wave-particle resonances of electrons with Alfven wave and ion acoustic wave.

关键词： Gyrokinetic particle simulation plasma turbulence electromagnetic gyrokinetic theory

One-step multi-compositional oxidation of YSi alloy:Experiments and ab initio computation

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Journal of Materials Science & Technology 2023年第27期158卷 253-262页

作者： W.J.Wang J.C.luo l.chen G.J.Yang State Key laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi’an Jiaotong UniversityXi’an 710049China Xi’an Jiaotong University Suzhou Institute Suzhou 215123China

YSi alloy is a promising candidate as oxidation resistant coatings for both the bond coat of environmental barrier coatings(EBCs)and anti-ablation coatings at a high temperature of∼1300℃.In this study,a one-step multi-compositional oxidation by rapid heating oxidation mode is proposed to reduce the oxidation rate by 3.6 times compared to conventional slow heating oxidation *** show that preferentially formed Y_(2)O_(3) oxide initiates a multi-step oxidation,produces a cracking and porous oxides,and thereby resulting in a fast oxidation with *** one-step multi-compositional oxidation with a compact and dense Y_(2)Si_(2)O_(7)scale contributes to the much better oxidation resistance for rapid heating oxidation mode of YSi *** stable formation of Y_(2)Si_(2)O_(7)scale is comprehensively understood by the energy barrier,charge density and electronic level based on density functional *** study demonstrates a promising application of YSi alloy by rapid heating oxidation mode.

关键词： YSi alloy One-step oxidation Multi-compositional scale Y_(2)Si_(2)O_(7) Energy barrier

Boosting cationic and anionic redox activity of li-rich layered oxide cathodes via li/Ni disordered regulation

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Journal of Energy Chemistry 2025年第1期100卷 533-543页

作者： Zewen liu Zhen Wu Hao Wang Xudong Zhang Yuanzhen chen Yongning liu Shengwu Guo Shenghua chen Yanli Nan Yan liu State Key laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University School of Materials Science and Engineering Xi'an University of Architecture and Technology Hefei Advanced Computing Center Operation Management Corp ltd Network Information Center Xi'an Jiaotong University

lithium-rich layered oxides （llOs） are increasingly recognized as promising cathode materials for nextgeneration high-energy-density lithium-ion batteries （lIBs）.However,they suffer from voltage decay and low initial Coulombic efficiency （ICE） due to severe structural degradation caused by irreversible O ***,we introduce a three-in-one strategy of increasing Ni and Mn content,along with li/Ni disordering and TM–O covalency regulation to boost cationic and anionic redox activity simultaneously and thus enhance the electrochemical activity of *** target material,li1.2Ni0.168Mn0.558Co0.074O2（l1）,exhibits an improved ICE of 87.2%and specific capacity of 293.2 mA h g-1and minimal voltage decay of less than 0.53 m V cycle-1over 300 cycles at 1C,compared to li1.2Ni0.13Mn0.54Co0.13O2（ls）(274.4 mA h g-1for initial capacity,73.8%for ICE and voltage decay of 0.84 mV/cycle over 300 cycles at 1C).Theoretical calculations reveal that the density of states （DOS） area near the Fermi energy level for l1 is larger than that of ls,indicating higher anionic and cationic redox reactivity than ***,l1 exhibits increased O-vacancy formation energy due to higher li/Ni disordering of 4.76%（quantified by X-ray diffraction Rietveld refinement） and enhanced TM–O covalency,making lattice O release more difficult and thus improving electrochemical *** increased li/Ni disordering also leads to more Ni2+presence in the li layer,which acts as a pillar during li+de-embedding,improving structural *** research not only presents a viable approach to designing low-Co llOs with enhanced capacity and ICE but also contributes significantly to the fundamental understanding of structural regulation in high-performance lIB cathodes.

关键词： Ice

ENERGETIC PARTIClE STABIlIZATION OF m=1 INTERNAl KINK MODE IN TOKAMAKS

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Chinese Physics letters 1987年第12期4卷 561-564页

作者： R.J.Hastie chen Yanping KE Fujiu CAI Shidong l.chen United Kingdom Atomic Energy Authority Culham LaboratoryAbingdomBerkshireEngland Institute of Physics Academic SinicaBeijing Plasma Physics laboratory Princeton UniversityPrincetonNew Jersey 08544

The stability of m=1 internal kink mode in a tokamak plasma with an anisotropic energetic particle component has been analyzed using the generalized energy *** is found that employing barely trapped energetic particle... 详细信息

关键词： properties TOKAMAK tokamak

FHl2 deficiency aggravates Candida albicans infection through decreased myelopoiesis

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Science China life Sciences 2025年

作者： Rongmei Gao Kanchao chen Yimin Wang Rongxia Guo Xiaoyu Zhang Peng Wu Weili Wang Qingxiang Huang Xuemei Xie Shangda Yang Yanling lü Qian Ren Fei liu Song chen Fengxia Ma Tao cheng Hui cheng State Key laboratory of Experimental Hematology National Clinical Research Center for Blood Diseases Haihe Laboratory of Cell Ecosystem Institute of Hematology & Blood Diseases Hospital Chinese Academy of Medical Sciences & Peking Union Medical College CAMS Center for Stem Cell Medicine PUMC Department of Stem Cell and Regenerative Medicine

Hematopoiesis is a finely tuned process that generates all blood cell types through self-renewal and differentiation, which is crucial for maintaining homeostasis. Acute infections can prompt a hematopoietic response known as emergency myelopoiesis. In this study, using a Candida albicans (C. albicans) infection model, we demonstrated for the first time that disruption of Fhl2 led to increased fungal burden,heightened inflammatory response and reduced survival rates. Impaired myeloid hematopoiesis and immune cell production were evident, as proved by the decreased numbers of hematopoietic stem and progenitor cells (HSPCs) and granulocytes in the bone marrow of Fhl2-deficient mice. In conclusion, FHl2 regulated emergency myelopoiesis in response to C. albicans, affecting the host’s defense against pathogens.

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THE MICROSTRUCTURE AND COMPRESSIVE PROPERTIES IN NiAl(Co) MATRIX COMPOSITE

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Acta Metallurgica Sinica(English letters) 1996年第6期9卷 653-657页

作者： l.chen Y.F. Han C.H Tao and M.l. Xie(Beijing Institute of Aeronautical Materials, Beijing 100095, ) Beijing Inst of Aeronautical Materials Beijing China

The microstructures of NiAl(Co)-TiB_2 composite prepared using exothermal dispersion (XD) method have been studied by optical microscopy, XRD, EDS, and TEM The results show that, TiB_2 paritcles are typically single crystal, and fairly uniformly distributed. The matrix mainly consists of β-NiAl phase, ll_2γ′Ni_3Al phase and δ-Ni_3Al phase. The δNi_3Al has a fcc crystal structure with lattice parameter a=*** data of compressive testing at room temperature show that the room temperature ductility of NiAl(Co) matrix composite is much better than that of stoichiometric NiAl.

关键词： intermetallic compound exothermal dispersion method

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Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 369-379页

作者： Mei Zhang Wenhao li Yangfei chen Yang Jiang Xiaofei Guo Han Dong School of Materials Science and Engineering Shanghai UniversityShanghai 200444China State Key laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China

The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile ***-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation *** findings were discussed with the local strain measurements via digital image *** results indicated that lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of *** small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-le Chatelier *** volume fraction of RA gradually decreased from 26.8%to 8.2%prior to *** the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase.

关键词： medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation

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AWECS:A linear Gyrokinetic df Particle-in-Cell Simulation Code for the Study of Alfvenic Instabilities in High-β Tokamak Plasmas

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Communications in Computational Physics 2008年第8期4卷 457-495页

作者： A.Bierwage l.chen Department of Physics and Astronomy University of CaliforniaIrvineCA 92697USA Institute for Fusion Theory and Simulation ZhejiangUniversityHangzhouChina

A 1-Dlinear gyrokinetic code called AWECS is developed to study the kinetic excitation of Alfvenic instabilities in a high-β tokamak plasma,with β being the ratio of thermal to magnetic *** is designed to describe physics associated with a broad range of frequencies and *** example,AWECS is capable of simulating kinetic ballooning modes,Alfvenic ion-temperature-gradient-driven modes,as well as Alfven instabilities due to energetic *** addition,AWECS may be used to study drift-Alfven instabilities in the low-β ***,the layout of the code and the numerical methods used are *** is benchmarked against other codes and a convergence study is carried out.

关键词： linear gyrokinetic simulation tokamak plasma drift-Alfv´en waves shear Alfv´en waves energetic particles

Spatial associations of tree species in a subtropical evergreen broad-leaved forest

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Journal of Plant Ecology 2012年第3期5卷 346-355页

作者： Zheng R.luo Ming J.Yu De l.chen You G.Wu Bing Y.Ding Key laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education and College of Life ScienceZhejiang UniversityHangzhou 310058China Management of Baishanzu Fengyangshan-Baishanzu National Nature ReserveQingyuan 323800China Department of Biology Science The School of Life and Environmental ScienceWenzhou UniversityWenzhou 325027China

Aims The spatial segregation hypothesis and the low-frequency hypothesis are two important proposed mechanisms that delay or prevent competitive exclusion in *** tree species interact with their neighbors,the importance of these potential processes can be investigated by analyzing the spatial structures of tree *** The distribution of the adults of 27 common tree species in a fully mapped 5-ha subtropical forest plot in Baishanzu,eastern China,was analyzed to investigate the community-level intra-and interspecific spatial association *** first tested for the overall spatial pattern in the 5-to 40-m neighborhoods and classified first-order bivariate associations with a diametric scheme based on Ripley’s K and nearest-neighbor statistic(G-function).Then heterogeneous Poisson null models were used to distinguish second-order interactions from overall spatial associations(including first-order effects).Finally,we analyzed correlations between the existence of species interactions and some attributes of the species *** Findings Partial overlap and segregation increased with scale,whereas mixing *** 70%of the species pairs occurred less than expected at random,and only 3.4%of the species pairs were well mixed;11.0%of all species pairs showed significant small-scale interactions,which was a greater frequency than expected by chance if species are abundant or prefer the same habitat,but less frequent than expected if species are highly *** suggests that both spatial segregation and low frequency of species facilitate species coexistence by reducing the opportunity that trees of two species encounter each *** study also revealed that positive interactions were more prevalent than negative interactions in the forest,which indicates that positive interactions may have important effects on forest species assemblies.

关键词： Baishanzu point pattern analysis spatial segregation low frequency interaction opportunity