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An explicit solution to a three-dimensional wedge problem considering two edges effect

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Friction 2020年第2期8卷 370-383页

作者： L.GUO z.m.zhang W.WANG Y.zHAO P.L.WONG School of mechatronic Engineering and Automation Shanghai UniversityShanghai 200444China Department of mechanical Engineering City University of Hong KongHong Kong SARChina

The paper presents an explicit matrix algorithm to solve the problem of an elastic wedge with three loaded *** algorithm makes use of a recently published concept of transformation matrix,by which the original surface loads are converted to equivalent loads in *** three loaded edges are considered *** developed algorithm is used to study the effects of two free edges of a steel block and tapered rollers with different contact *** two load-free edges can substantially increase deformation if the two edges are close in *** results of the tapered roller simulation show that deformation is considerably sensitive to the contact angle of the tapered *** largest deformation appears at the big end of the ***,empirical formulae for correction factors for the calculation of block or quarter-space deformation based on half-space solutions are summarized.

关键词： contact mechanics two edge surfaces finite line contact tapered roller contact

ENERGY-LOSS FUNCTIONS DERIVED FROm REELS SPECTRA FOR ALUmINUm

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Acta metallurgica Sinica(English Letters) 2005年第3期18卷 217-222页

作者： z.m.zhang z.J.Ding H.m.Li K.Salma X.Sun R.Shimizu T.Koshikawa K.Goto StructureResearchLaboratoryandDepartmentofPhysics UniversityofScienceandTechnologyofChinaTheChineseAcademyofSciencesHefei230026China DepartmentofInformationScience OsakaInstituteofTechnologyOsaka573-0196Japan FundamentalElectronicsResearchInstitute OsakaElectro-CommunicationUniversityOsaka572-8530Japan DepartmentofSystemsEngineering NagoyaInstituteofTechnologyNagoya466-8555Japan

The effective energy loss functions for Al have been derived from differential i nverse inelastic mean free path based on the extended Landau approach. It has be en revealed that the effective energy loss function is very close in value to th e theoretical surface energy loss function in the lower energy loss region but g radually approaches the theoretical bulk energy loss function in the higher ener gy loss region. moreover, the intensity corresponding to surface excitation in e ffective energy loss functions decreases with the increase of primary electron e nergy. These facts show that the present effective energy loss function describe s not only surface excitation but also bulk excitation. At last, REELS spectra s imulated by monte Carlo method based on use of the effective energy loss functio ns has reproduced the experimental REELS spectra with considerable success.

关键词： effective energy loss function monte Carlo simulation extended Landau approach reflection electron energy loss spectro scopy Aluminum

INFLUENCE OF zIRCONIUm ON mICROSTRUCTURE AND DAmPING CAPACITY OF zA27 ALLOY

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Acta metallurgica Sinica(English Letters) 1998年第3期11卷 230-234页

作者： J.C.Wang z.m.zhang Y.L.Lu G.S.Song G.C.Yang Northwestern Polytechnical Univ Xi'an China

To improve the damping capacities of metals and alloys, the microstructures and damping capacities of zA27 alloy modified by zr were studied, and the damping capacities at room tempemture were measured by using cantilever beam techniques. The experiment results show that zr can refine the Al-rich primary phase and improve the damping Capacities saliently. Compared with the un-modified one, the damping capacity of zA27 alloy modified by 0.3wt%zr received 90 percent increment. The high damping capacities are attributed primarily to grain ablement and the increasing of phase interfaces.

关键词： zA27 alloy damping capacity modification microstructure

Investigation of magnetic inhibition effect on ion acceleration at high laser intensities

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matter and Radiation at Extremes 2021年第4期6卷 1-9页

作者： H.Huang z.m.zhang B.zhang W.Hong S.K.He L.B.meng W.Qi B.Cui W.m.zhoua Science and Technology on Plasma Physics Laboratory Mianyang 621900China

The irradiation of a target with high laser intensity can lead to self-generation of an intense magnetic field(B-field)on the target *** has therefore been suggested that the sheath-driven acceleration of high-energy protons would be significantly hampered by the magnetization effect of this self-generated B-field at high enough laser *** this paper,particle-in-cell simulations are used to study this magnetization effect on sheath-driven proton *** is shown that the inhibitory effect of the B-field on ion acceleration is not as significant as previously ***,it is shown that the magnetization effect plays a relatively limited role in high-energy proton acceleration,even at high laser intensities when the mutual coupling and competition between self-generated electric(E-)and B-fields are considered in a realistic sheath acceleration scenario.A theoretical model including the v 3 B force is presented and confirms that the rate of reduction in proton energy depends on the strength ratio between B-and E-fields rather than on the strength of the B-field alone,and that only a small percentage of the proton energy is affected by the self-generated ***,it is shown that the degraded scaling of proton energy at high laser intensities can be explained by the decrease in acceleration time caused by the increased sheath fields at high laser intensities rather than by the magnetic inhibitory effect,because of the longer growth time scale of the *** understanding of the magnetization effect may pave the way to the generation of high-energy protons by sheath-driven acceleration at high laser intensities.

关键词： field. acceleration effect

All-optical μ^- acceleration in the laser wakefield

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High Power Laser Science and Engineering 2018年第4期6卷 119-124页

作者： F.zhang z.G.Deng L.Q.Shan z.m.zhang B.Bi D.X.Liu W.W.Wang z.Q.Yuan C.Tian S.Q.Yang B.zhang Y.Q.Gu Science and Technology on Plasma Physics Laboratory Laser Fusion Research CenterChina Academy of Engineering Physics IFSA Collaborative Innovation Center Shanghai Jiao Tong University

muons produced by the Bethe–Heitler process from laser wakefield accelerated electrons interacting with high z materials have velocities close to the laser wakefield. It is possible to accelerate those muons with laser wakefield *** for the first time we propose an all-optical ‘Generator and Booster’ scheme to accelerate the produced muons by another laser wakefield to supply a prompt, compact, low cost and controllable muon source in laser laboratories. The trapping and acceleration of muons are analyzed by one-dimensional analytic model and verified by two-dimensional particle-in-cell(PIC) simulation. It is shown that muons can be trapped in a broad energy range and accelerated to higher energy than that of electrons for longer dephasing length. We further extrapolate the dependence of the maximum acceleration energy of muons with the laser wakefield relativistic factor γ and the relevant initial energy E_0. It is shown that a maximum energy up to 15.2 GeV is promising with γ = 46 and E_0= 1.45 Ge V on the existing short pulse laser facilities.

关键词： laser wakefield acceleration muon source

一种新的模糊控制器及其在工业机器人中的应用

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模糊系统与数学 1987年第0期 90-103页

作者：张志明汪培庄北京师范大学数学系

本文在分析了机器人控制系统与一般模糊控制系统的区别后,结合Fuzzy逻辑,沿用常规PID形式,提出了一种新型的模糊控制算法,以便能把模糊控制应用到机器人控制系统中来,并简化了模糊控制器的设计过程。大量仿真实验表明,由此新算法所得到... 详细信息

本文在分析了机器人控制系统与一般模糊控制系统的区别后,结合Fuzzy逻辑,沿用常规PID形式,提出了一种新型的模糊控制算法,以便能把模糊控制应用到机器人控制系统中来,并简化了模糊控制器的设计过程。大量仿真实验表明,由此新算法所得到的新模糊控制器的各项性能优于或同于PID,并对第二种类型的机器人仿真结果证实了模糊控制应用于机器人的可行性。文中给出了众多的响应曲线、表格、仿真结果,并对结果进行了分析。

关键词：模糊控制器汪培庄工业机器人产业机器人机器人仿真 PID

Transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 177-192页

作者： m.NAVEED m.ImRAN T.ASGHAR z.ABBAS Department of mathematics Division of Science and TechnologyUniversity of Education Department of mathematics The Islamia University of Bahawalpur

This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic fields is also inspected in terms of their physical characteristics. To depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAm).The effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

关键词： hybrid nanofluid oscillating curved stretchable sheet gyrotactic microorganism Cattaneo-Christov heat and mass flux chemical reaction analytical solution O368

Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural Regeneration Research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian Shen Robert J.Thomas m.Brandon Westover Can zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain Research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging Research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(zhang, 2023).

关键词： Alzheimer inflammation hypothesis

Dielectric-ion-conductive znNb2O6 layer enabling rapid desolvation and diffusion for dendrite-free zn metal batteries

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Journal of Energy Chemistry 2025年第1期100卷 693-701页

作者： Haifeng Yang Jian Wang Panpan zhang Xiaomin Cheng Qinghua Guan Jing Dong Bixian Chen Lujie Jia Jing zhang Yongzheng zhang Yunjian Liu Hongzhen Lin School of materials Science and Engineering Jiangsu University i-Lab & CAS Key Laboratory of Nanophotonic materials and Devices Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Helmholtz Institute Ulm (HIU) Karlsruhe Institute of Technology (KIT) School of materials Science and Engineering Xi'an University of Technology State Key Laboratory of Chemical Engineering East China University of Science and Technology

Rechargeable aqueous zinc-metal batteries （AzmBs） are promising candidates for large-scale energy storage systems due to their low cost and high ***,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the zn（H2O）62+solvation ***,learnt from self-generated solid electrolyte interphase （SEI） in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic zn surface （zNB@zn）,acting as a rapid desolvation *** zincophilic and dielectric-conductive properties of zNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical ***,the as-prepared zNB@zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility （99.54%） even under high current density and depth of discharge ***,the assembled zNB@zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g-1and outstanding rate performance up to 10 A *** large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AzmBs.

关键词： zn metal battery Dielectric artificial layer Rapid ion diffusion zincophilic diffusion Active water inhibition