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Preparation of Al_(72)Ni_8Ti_8Zr_6Nb_3Y_3 amorphous powders and bulk materials

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International Journal of Minerals,Metallurgy and Materials 2016年第10期23卷 1187-1195页

作者： Yu Wu Xin-fu Wang fu-sheng Han Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences

Amorphous Al_（72）Ni_8Ti_8Zr_6Nb_3Y_3 powders were successfully fabricated by mechanical alloying. The microstructure, glass-forming ability, and crystallization behavior of amorphous Al_（72）Ni_8Ti_8Zr_6Nb_3Y_3 powders were investigated by X-ray diffraction（XRD）, transmission electron microscopy（TEM）, and differential scanning calorimetry（DSC）. The isothermal crystallization kinetics was analyzed by the Johnson-Mehl-Avrami equation. In the results, the supercooled liquid region of the amorphous alloy is as high as 81 K, as determined by-non-isothermal DSC curves. The activation energy for crystallization is as high as 312.6 kJ ·mol1 obtained by Kissinger and Ozawa analyses. The values of Avrami exponent（n） imply that the crystallization is dominated by interface-controlled three-dimensional growth in the early stage and the end stage and by diffusion-controlled two- or three-dimensional growth in the middle stage. In addition, the amorphous Al_（72）Ni_8Ti_8Zr_6Nb_3Y_3 powders were sintered under 2 GPa at temperatures of 673 K and 723 K. The results show that the Vickers hardness of the compacted powders is as high as Hv 1215.

关键词： amorphous alloys mechanical alloying thermal stability pressing Vickers hardness

Fault detection for networked systems subject to access constraints and packet dropouts

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Journal of Systems Engineering and Electronics 2011年第1期22卷 127-134页

作者： Xiongbo Wan Huajing Fang sheng fu Department of Control Science and Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China

This paper addresses the problem of fault detection（FD） for networked systems with access constraints and packet *** independent Markov chains are used to describe the sequences of channels which are available for communication at an instant and the packet dropout process,*** indexes H∞ and H_ are introduced to describe the robustness of residual against external disturbances and sensitivity of residual to faults,*** using a mode-dependent fault detection filter（FDF） as residual generator,the addressed FD problem is converted into an auxiliary filter design problem with the above index constraints.A sufficient condition for the existence of the FDF is derived in terms of certain linear matrix inequalities（LMIs）.When these LMIs are feasible,the explicit expression of the desired FDF can also be characterized.A numerical example is exploited to show the usefulness of the proposed results.

关键词： fault detection(FD) networked control system(NCS) access constraints packet dropouts linear matrix inequality(LMI).

Neutrophils in liver diseases:pathogenesis and therapeutic targets

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Cellular & Molecular Immunology 2021年第1期18卷 38-44页

作者： Kai Liu fu-sheng Wang Ruonan Xu Peking University 302 Clinical Medical School BeijingChina Treatment and Research Center for Infectious Diseases The Fifth Medical Center of PLA General HospitalNational Clinical Research Center for Infectious DiseasesBeijingChina

Previously,it was assumed that peripheral neutrophils are a homogeneous population that displays antimicrobial ***,recent data have revealed that neutrophils are heterogeneous and are additionally involved in tissue damage and immune *** phenotypic and functional plasticity of neutrophils has been identified in patients with cancer,inflammatory disorders,infections,and other ***,neutrophils,with their autocrine,paracrine,and immune modulation functions,have been shown to be involved in liver diseases,including viral hepatitis,nonalcoholic steatohepatitis,alcoholic liver disease,liver fibrosis,cirrhosis,liver failure,and liver ***,this review summarizes the role of neutrophils in liver diseases.

关键词： Liver disease Liver injury Neutrophil Innate immunity Immunotherapy

Microstructure and mechanical properties of high-strength low alloy steel by wire and arc additive manufacturing

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维普期刊数据库

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International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 933-942页

作者： Yi-li Dai sheng-fu Yu An-guo Huang Yu-sheng Shi State Key Laboratory of Material Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

A high-building multi-directional pipe joint(HBMDPJ)was fabricated by wire and arc additive manufacturing using high-strength low-alloy(HSLA)*** microstructure characteristics and transformation were observed and *** results show that the forming part includes four *** solidification zone solidifies as typical columnar crystals from a molten *** complete austenitizing zone forms from the solidification zone heated to a temperature greater than 1100℃,and the typical columnar crystals in this zone are difficult to *** partial austenitizing zone forms from the completely austenite zone heated between Ac1(austenite transition temperature)and1100℃,which is mainly equiaxed *** several thermal cycles,the partial austenitizing zone transforms to the tempering zone,which consistes of fully equiaxed *** the solidification zone to the tempering zone,the average grain size decreases from 75 to20μ*** mechanical properties of HBMDPJ satisfies the requirement for the intended application.

关键词： wire and arc additive manufacturing high strength low alloy steel microstructure inclusions fine grain ferrite mechanical properties

COPOLYMERIZATION OF ETHYLENE AND 1-HEXENE WITH TiCl_4/MgCl_2 CATALYSTS MODIFIED BY 2,6-DIISOPROPYLPHENOL

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Chinese Journal of Polymer Science 2013年第1期31卷 110-121页

作者： sheng-jie Xia Zhi-sheng fu Xiao-yan Liu 范志强 MOE Key Laboratory of Macromolecular Synthesis and functionalization Department of Polymer Science and EngineeringZhejiang University

A supported TiCl4/MgCl2 catalyst without internal electron donor （O-cat） was prepared firstly. Then it was modified by 2,6-diisopropylphenol to make a novel modified catalyst （M-cat）. These two catalysts were used to catalyze ethylene/l-hexene copolymerization and l-hexene homopolymerization. The influence of cocatalyst and hydrogen on the catalytic behavior of these two catalysts was investigated. In ethylene/l-hexene copolymerization, the introduction of 2,6- iPr2C6H3O- groups did not deactivate the supported TiCl4/MgCl2 catalyst. Although the 1-hexene incorporation in ethylene/1- hexene copolymer prepared by M-cat was lower than that prepared by O-cat, the composition distribution of the former was narrower than that of the latter. Methylaluminoxane （MAO） was a more effective activator for M-cat than triisobutyl- aluminium （TIBA）. MAO led to higher yield and more uniform chain structure. In 1-hexene homopolymerization, the presence of 2,6-ipr2C6H3O- groups lowered the propagation rate constants. Two types of active centers with a chemically bonded 2,6-iprzCaH3O- group were proposed to explain the observed phenomena in M-cat.

关键词： Supported Ziegler-Natta catalyst 2,6-Diisopropylphenol Ethylene copolymerization Active center distribution.

Conjugate Points on a Type of Kahler Manifolds

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Acta Mathematica Sinica,English Series 2013年第6期29卷 1175-1184页

作者： Wei Ming LIU fu sheng DENG Department of Mathematics and Physics Beijing Institute of Petrochemical Technology School of Mathematical Sciences Graduate University of Chinese Academy of Sciences

We study conjugate points on a type of Khler manifolds, which are submanifolds of Grassmannian manifolds. And then we give the applications to the study of the index of geodesics and homotopy groups.

关键词： Conjugate points Jacobi equation Khler manifolds

ANALYSIS OF INTER-LAMINAR STRESSES FOR COMPOSITE LAMINATED PLATE WITH INTERFACIAL DAMAGE

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Acta Mechanica Solida Sinica 2008年第2期21卷 127-140页

作者： Yiming fu sheng Li Yejie Jiang College of Mechanics and Aerospace Hunan University Changsha 410082 China

A constitutive model for composite laminated plates with the damage effect of the intra-layers and inter-laminar interface is presented. The model is based on the general six-degrees-of-freedom plate theory, the discontinuity of displacement on the interfaces are depicted by three shape functions, which are formulated according to solutions satisfying three equilibrium equations, By using the variation principle, the three-dimensional non-linear equilibrium differential equations of the laminated plates with two different damage models are derived. Then, considering a simply supported laminated plate with damage, an analytical solution is presented using finite difference method to obtain the inter-laminar stresses.

关键词： composite laminated plates geometric nonlinearity inter-laminar stress analysis interracial damage the finite difference method

Fridman’s Invariant, Squeezing functions, and Exhausting Domains

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Acta Mathematica Sinica,English Series 2019年第10期35卷 1723-1728页

作者： fu sheng DENG Xu Jun ZHANG School of Mathematical Sciences University of Chinese Academy of Sciences

We show that if a bounded domain Ω is exhausted by a bounded strictly pseudoconvex domain D with C^2 boundary, then Ω is holomorphically equivalent to D or the unit ball, and show that a bounded domain has to be hol... 详细信息

关键词： Squeezing function Fridman's invariant exhausting domain

THE ANALYSIS OF INTERLAMINAR STRESSES FOR COMPOSITE LAMINATED SHALLOW SHELLS WITH INTERFACIAL DAMAGE

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Acta Mechanica Solida Sinica 2011年第6期24卷 539-555页

作者： Yiming fu sheng Li Yiqi Mao College of Mechanics and Aerospace Hunan University Changsha 410082 China

Based on the general six-degrees-of-freedom plate theory towards the accurate stress analysis and nonlinear theory of shallow shells, considering the damage effect of the interlaminar in- terface and using the variation principle, the three-dimensional non-linear equilibrium differential equations of the laminated shallow shells with interfacial damage are derived. Then, considering a simply supported laminated shallow shell with damage and under normal load, an analytical solution is presented by using finite difference method to obtain the interlaminar stresses. Numer- ical results show, the stiffness of the shell is weakened, greater absolute values of displacements as well as smaller interlaminar stresses are obtained by interfacial damage. When the interfacial damage is further increased, delamination occurs obviously under normal pulling load and pure shear slip occurs under normal pressure load. The portion of the load undertaken by the two sides of the interface is more different. Different mechanical behaviors are shown in both sides of the interface, and the discontinuation of stresses and displacements takes place in the interface.

关键词： laminated shallow shells geometric nonlinearity accurate stress analysis interracialdamage inter-laminar stresses