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热轧方形中空截面的残余应力分析

钢结构(中英文) 2009年第6期 83-84页

作者： S.H.Li,G.Zeng,y.F.Ma,y.j.guo and X.M.Lai

残余应力对热轧构件的受力性能和强度有很大影响。主要分析了热轧方形中空截面的残余应力。超过600部文献或文章的记载表明,可以使用X射线衍射法分析沿厚度方向的外表面和内表面的残余应力。试验结果对该截面残余应力的量级和分布分析... 详细信息

残余应力对热轧构件的受力性能和强度有很大影响。主要分析了热轧方形中空截面的残余应力。超过600部文献或文章的记载表明,可以使用X射线衍射法分析沿厚度方向的外表面和内表面的残余应力。试验结果对该截面残余应力的量级和分布分析提供了数据。最大的残余应力产生在焊缝上,沿厚度变化的残余应力分布呈现出双线性特性。同时发现,方形截面残余应力的形成过程对其外表面纵向残余应力分布影响很大。

关键词：残余应力热轧 X射线衍射法形成过程

Effective cellular vaccines generated by in vitro or in vivo modification of tumor cells using gene transfer approaches for cancer immunogene therapy

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中国实验血液学杂志 1997年第3期5卷 284-285页

作者： y.j.guo F.Shen T.P.Xie X.Che Z.F.Cui L.Shi j.Ma S.G.Wu X.N.Wang G.L.Liu y.Liu H.Wang H.L.Huang L.X.Wei j.Zhao j.Trojan A.Ly D.Anthony M.C.Wu Tumor Immunology and Gene Therapy Center Institute of Hepatobiliary Surgery and Changhai HospitalThe Second Military Medical University and Sidney Kimmel Cancer CenterCaliforniaUSA

Tumor cells escape host immune surveillance bydown-regulation of MHC and/or ***-tumor immune responses are mediated primarily by T cells.A deficiency in either MHC or co-stimulatory molecules on tumor cells is associa... 详细信息

关键词： vaccines surveillance immunity transfection recurrence manner escape curative elicit inducing

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New methods to find solutions and analyze stability of equilibrium of nonholonomic mechanical systems

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Acta Mechanica Sinica 2018年第6期34卷 1136-1144页

作者： j.Chen y.X.guo F.X.Mei School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Physics Liaoning UniversityShenyang 110000China

A large proportion of constrained mechanical systems result in nonlinear ordinary differential equations,for which it is quite difficult to find analytical *** initial motions method proposed by Whittaker is effective to deal with such problems for various constrained mechanical systems,including the nonholonomic systems discussed in the first part of this paper,where in addition to differential equations of motion,nonholonomic constraints *** final equations of motion for these systems are obtained in the form of corresponding power ***,an alternative,direct method to determine the initial values of higher-order derivatives(q)0,(q)0,…is proposed,being different from that of *** second part of this work analyzes the stability of equilibrium of less complex,nonholonomic mechanical systems represented by gradient *** discuss the stability of equilibrium of such systems based on the properties of the gradient *** advantage of this novel method is its avoidance of the difficulty of directly establishing Lyapunov functions aimed at such unsteady nonlinear ***,these theoretical considerations are illustrated through four examples.

关键词： Nonholonomic system Initial motions Gradient system Lyapunov function Stability

Influence of the velocity barrier on the massive Dirac electron transport in a monolayer MoS2 quantum structure

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Frontiers of physics 2020年第3期15卷 113-121页

作者： X.-j.Hao R.-y.yuan j.-j.jin y.guo Center for Theoretical Physics Department of PhysicsCapital Normal UniversityBeijing100048China Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics Tsinghua UniversityBeijing100084China Collaborative Innovation Center of Quantum Matter BeijingChina

Using the transfer matrix method,spin-and valley-dependent electron transport properties modulated by the velocity barrier were studied in the normal/ferromagnetic/normal monolayer MoS2 quantum *** on Snell’s Law in optics,we define the velocity barrier asξ=v2/v1 by changing the Fermi velocity of the intermediate ferromagnetic region to obtain a deflection condition during the electron transport process in the *** results show that both the magnitude and the direction of spin-and valley-dependent electron polarization can be regulated by the velocity barrier.−100%polarization of spin-and valley-dependent electron can be achieved forξ>1,while 100%polarization can be obtained forξy transport always occur at a large incident *** addition,the spin-and valley-dependent electron transport considerably depends on the length kFL and the gate voltage U(x)of the intermediate ferromagnetic *** findings provide an effective method for designing novel spin and valley electronic devices.

关键词： velocity barrier monolayer MoS2 spin valley polarization

On the mechanism of Si-promoted destabilization of TiC_(x)particles in Al alloys

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journal of Materials Science & Technology 2023年第34期165卷 17-26页

作者： H.Dong y.C.guo y.Z.Chen F.Xia Q.Q.guo Q.Chen G.L.Li j.y.Zhao y.Zhong j.P.Li School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an 710021China State Key Lab.of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China School of Science Xi’an University of Science and TechnologyXi’an 710054China

TiC_(x)is an excellent composite strengthening particle and grain refiner for Al ***,the stability of TiC_(x)is poor when solute Si exists in Al alloy melts,which significantly depresses its strengthening and grain refining *** this work,the destabilization mechanisms of the TiC_(x)particles in Al-Si alloy melt with a composition of Al-7Si-7.5TiC were explored via experiments,first-principles calculations and thermodynamic *** experimental results show that Si atoms diffuse into TiC_(x)and Ti atoms are released into the Al melt to form a Ti-rich transition zone during the insulation of TiC_(x)in Al-Si melt,and the TiAlySiz and Al_(4)C_(3)phases are solidified in the Ti-rich zone and at Ti-rich zone/TiC_(x)interface,*** first principles calculations show that the low formation energy of C vacancies facilitates the rapid diffusion of Si atoms in TiC_(x),while the doping of Si atoms reduces the energy barrier of diffusion of Ti atoms in TiC_(x)and promotes the formation of Ti-rich *** thermodynamic calculations show that the wide crystallization temperature range of the destabilized product TiAlySiz phase is the key to continuous decomposition of TiC_(x)*** addition,the driving force of the main destabilization reaction of TiC_(x)in the Al-Si alloys is about 44 times higher than that in the Al alloys without Si *** indicates that the presence of solute Si remarkably promotes the subsequent decomposition process of TiC_(x)in the Al-Si alloy melts.

关键词： Al-Si alloy TiC_(x)particles Destabilization First principles calculations Thermodynamics

FORMABILITy CRITERIA OF INTERMETALLIC COMPOUNDS CONTAINING TRANSITION METAL SySTEMS

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中国有色金属学会会刊：英文版 1997年第3期7卷 136-139页

作者： guo, j Li, CH Qin, P Chen, Ny Cao, y Qiu, GF CHINESE ACAD SCI SHANGHAI INST METSHANGHAI 200050PEOPLES R CHINA SUZHOU UNIV DEPT CHEMSUZHOU 215006PEOPLES R CHINA

ＦＯＲＭＡＢＩＬＩＴＹＣＲＩＴＥＲＩＡＯＦＩＮＴＥＲＭＥＴＡＬＬＩＣＣＯＭＰＯＵＮＤＳＣＯＮＴＡＩＮＩＮＧＴＲＡＮＳＩＴＩＯＮＭＥＴＡＬＳＹＳＴＥＭＳＧｕｏＪｉｎ，ＬｉＣｈｏｎｇｈｅ，ＱｉｎＰｅｉ，ＣｈｅｎＮｉａｎｙ... 详细信息

ＦＯＲＭＡＢＩＬＩＴＹＣＲＩＴＥＲＩＡＯＦＩＮＴＥＲＭＥＴＡＬＬＩＣＣＯＭＰＯＵＮＤＳＣＯＮＴＡＩＮＩＮＧＴＲＡＮＳＩＴＩＯＮＭＥＴＡＬＳＹＳＴＥＭＳＧｕｏＪｉｎ，ＬｉＣｈｏｎｇｈｅ，ＱｉｎＰｅｉ，ＣｈｅｎＮｉａｎｙｉＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔ...

关键词： formability criterion intermetallic compound transition element

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Twinning behavior of hot extruded AZ31 hexagonal prisms during uniaxial compression

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journal of Magnesium and Alloys 2019年第1期7卷 90-97页

作者： y.R.Zhao L.L.Chang j.guo y.P.jin School of Materials Science and Engineering Shandong UniversityJinanShandong 250061China Key Laboratory for Liquid-Solid Structure Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China

Hot-extruded magnesium alloy AZ31 bar was cut into hexagonal prisms and then compressed at room temperature with the loading direction parallel to the extrusion direction(ED)or perpendicular to *** effective stress and strain evolution at center and corner region of the hexagonal prisms was simulated by using DEFORM 3D,while microstructure evolution was characterized by electron backscatter diffraction(EBSD).Relationship between twinning behavior and stress-strain evolution during compression at room temperature was *** results indicated that the compressive stress and strain levels at central region of hexagonal prisms were lower than those at the corner *** examination revealed that{10-12}twins activate during the compression and the volume fraction of twins at corner parts were less than that at the central parts,which was attributed to twin thickening and coalescence ***,the EBSD map indicated that the arise of{10-11}contraction twins and{10-11}-{10-12}double twins in compressed samples,especially in the corner region with loading axis perpendicular to ED,which were considered to be related to the high stress level at corner *** dislocation slips led to low-angle boundaries in LA⊥ED and LA//ED.

关键词： Magnesium alloy Simulation Microstructure Twinning Coalescence

旅游地魅力对旅游者忠诚影响的中介与调节作用

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海南大学学报（人文社会科学版） 2025年第1期43卷 236-246页

作者：郭安禧郭英之上海商学院酒店管理学院上海201400 复旦大学旅游学系上海200433

旅游地魅力是近些年被提出和关注的新话题,目前考察旅游地魅力如何影响旅游者忠诚的研究尚少。本研究基于理智人模型、心理连续体模型和期望不一致理论,以享乐幸福感、实现幸福感、地方依赖、地方认同为中介和旅游体验质量为调节,探讨... 详细信息

旅游地魅力是近些年被提出和关注的新话题,目前考察旅游地魅力如何影响旅游者忠诚的研究尚少。本研究基于理智人模型、心理连续体模型和期望不一致理论,以享乐幸福感、实现幸福感、地方依赖、地方认同为中介和旅游体验质量为调节,探讨旅游地魅力对旅游者忠诚影响的中介路径和边界条件。通过对旅游者问卷调查获得的444份有效问卷进行实证分析,结果显示:旅游地魅力对旅游者忠诚没有显著直接影响,享乐幸福感、地方依赖、地方认同在二者间起完全中介作用;旅游地魅力能提升享乐幸福感和实现幸福感,享乐幸福感会提升旅游者忠诚度,但实现幸福感不会提升旅游者忠诚度;旅游地魅力能增强地方依赖和地方认同,地方依赖和地方认同又能增强旅游者忠诚;旅游体验质量在旅游地魅力与实现幸福感、地方依赖、地方认同的作用关系中起正向调节作用。

关键词：旅游地魅力旅游者幸福感地方依恋旅游者忠诚旅游体验质量

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One kind motion of controllable constrained Birkhoffian system:the absence of constraints

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Acta Mechanica Sinica 2020年第3期36卷 735-741页

作者： j.Chen F.X.Mei S.X.Liu y.X.guo School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Physics Liaoning UniversityShenyang 110000China

This paper is devoted to discuss the motion of controllable constrained Birkhoffian system along with its absence of *** first step is to establish the autonomous and non-autonomous differential equations of motion of the system,based on Pfaff-Birkhoff ***,the existence of constraint multipliers are exhaustively ***,the definition of one kind motion of the system,called free motion,is given,which is described and analyzed by the absence of constraints that are determined by constraint *** 2 illustrates that one system can realize its free motion by selecting proper control *** particular,theorem 2 provides that one system can naturally realize free motion when we consider the integral of the unconstrained Birkhoffian system as the constraints of constrained Birkhoffian ***,the results obtained are illustrated by several examples.

关键词： Constrained Birkhoffian system Kinematic control Absence of constraint Free motion