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Combined approach.for analysing evolutionary power spectra of a track-soil system under moving random loads

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Acta Mech.nica Sinica 2019年第3期35卷 674-690页

作者： y.zhao L.T.Si h.Ouyang State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Center for Computational MechanicsDalian University of TechnologyDalian 116023Chin Sch.ol of Engineering University of LiverpoolLiverpool L69 3GHUK

Th. pseudo-excitation meth.d combined with.th. integral transform meth.d (PEM-ITM) is presented to investigate th. ground vibration of a coupled track-soil system induced by moving random loads. Commonly in th. track model, th. rail, sleepers, rail pads, and ballast are modelled as an infinite Euler beam, discretely distributed masses, discretely distributed vertical springs, and a viscoelastic layer, respectively. Th. soil is regarded as a h.mogenous isotropic h.lf-space coupled with.th. track using th. boundary condition at th. surface of th. ground. By introducing a pseudo-excitation, th. random vibration analysis of th. coupled system is converted into a h.rmonic analysis. Th. analytical form of evolutionary power spectral density responses of th. simplified coupled track-soil system under a random moving load is derived in th. frequency/wavenumber domain by PEM-ITM. In th. numerical examples, th. effects of different parameters, such.as th. moving speed, th. soil properties, and th. coh.rence of moving loads, on th. ground response are investigated.

关键词： Track-soil system Moving random loads Evolutionary power spectrum Pseudo-excitation meth.d Integral transform meth.d Vibration transmission

Th. Role of TNF Related Apoptosis-Inducing Ligand in Neurodegenerative Diseases

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Cellular & Molecular Immunology 2005年第2期2卷 113-122页

作者： y.h.ang N.Erdmann h.Peng y.zhao Th.laboratoryofNeurotoxicologyatth.CenterforNeurovirology＆NeurodegenerativeDisorders ／／Dept.Pharmacology Dept.ofSurgery UniversityofNebraskaMedicalCenterOmahaNE68198-5880USA／／InstituteofAnimalResearchChineseAcademyofScienceChina

A h.llmark of all forms of neurodegenerative diseases is impairment of neuronal functions,and in many cases neuronal cell *** th. etiology of neurodegenerative diseases may be distinct,different diseases display a similar path.genesis,for example abnormal immunity with.n th. central nervous system(CNS),activation of macroph.ge/microglia and th. involvement of proinflammatory *** studies sh.w th.t neurons in a neurodegenerative state undergo a h.gh.y regulated programmed cell death.also called ***-related apoptosis-inducing ligand(TRAIL),a member of th. TNF family,h.s been sh.wn to be involved in apoptosis during many *** one member of a death.ligand family,TRAIL was originally th.ugh. to target only tumor cells and was not present in ***,recent data sh.wed th.t TRAIL was unregulated in h.V-1-infected and immune-activated macroph.ges,a major disease inducing cell during h.V-1-assoeiated dementia(h.D).TRAIL is also induced on neuron by β-amyloid protein,an important path.gen for Alzh.imer's *** th.s review,we summarize th. possible common aspects th.t TRAIL involved th.se neurodegenerative diseases,TRAIL induced apoptosis signaling in th. CNS cells,and specific role of TRAIL in individual *** & Molecular Immunology.2005;2(2):113-122.

关键词： Alzh.imer's disease h.-1 associated dementia multiple sclerosis apoptosis TRAIL macroph.ge

In-situ measurement of th. surface temperature during h.lograph.c recording

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Ch.nese Optics Letters 2008年第1期6卷 25-28页

作者： A.Draude R.Meinh.rdt h.Franke y.zhao R.A.Lessard Department of Ph.sics/Applied Ph.sics University of Duisburg-Essen Département de ch.mie Universitéde SherbrookeSherbrookeQuébec COPL Département de physiquegénie physique et optiqueUniversité LavalQuébec

Ph.to-induced processes in organic materials mostly occur on molecular levels. Excited molecules may split to form radicals, starting a polymerization process with.diffusing monomers. Th. azo-dyes perform an optically induced cis-trans isomerization. During pattern formation like a h.lograph.c grating, th. local temperature increase, especially in th.n films, is up to date a subject of estimation from absorption and dissipation data. h.wever, th. exact knowledge of th. surface temperature would h.lp a lot in understanding th. resulting refractive index and th.ckness patterns during h.lograph.c exposure. In th.s paper, in-situ pyrometer measurements are presented. As examples, different ph.tosensitive materials, varying from a ph.topolymer to polycrystalline azo dyes, are used in order to outline th. magnitude of th.s effect and demonstrate th. feasibility of th.s tech.ique.

关键词： h.lograph.c gratings h.lograph.c recording Ph.tosensitive materials Refractive index Surface measurements Th.n films

An Efficient Parallel/Unstructured-Multigrid Implicit Meth.d for Simulating 3D Fluid-Structure Interaction

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Communications in Computational Ph.sics 2008年第7期4卷 350-377页

作者： X.Lv y.zhao X.y.h.ang G.h.Xia X.h.Su Sch.ol of Mech.nical and Aerospace Engineering College of EngineeringNanyang Technological UniversitySingapore 639798.

A finite volume(FV)meth.d for simulating 3D Fluid-Structure Interaction(FSI)is presented in th.s *** fluid flow is simulated using a parallel unstructured multigrid preconditioned implicit compressible solver,wh.st a 3D matrix-free implicit unstructured multigrid finite volume solver is employed for th. structural *** two modules are th.n coupled using a so-called immersed membrane meth.d(IMM).Large-Eddy Simulation(LES)is employed to predict *** from several moving boundary and FSI problems are presented to validate proposed meth.ds and demonstrate th.ir efficiency。

关键词： Finite volume meth.d moving boundary fluid-structure interaction unstructured multigrid computational structural mech.nics immersed membrane meth.d large-Eddy simulation.

h.speromyces virescens(Fungi, Ascomycota, Laboulbeniales)attacking h.rmonia axyridis(Coleoptera, Coccinellidae)in its native range

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Ch.nese Science Bulletin 2014年第5期59卷 528-532页

作者： h.elewaters Danny Rich.rd F.Comont Serena y.zhao Donald h.Pfister Department of Organismic and Evolutionary Biology Harvard University NERC Centre for Ecology & h.drology Maclean Building Kraus Natural Science Building University of Michigan

Th.s study intended to find data on obligate ectoparasitic Laboulbeniales(Fungi,Ascomycota)on Ch.nese h.rmonia axyridis(Coleoptera,Coccinellidae).After h.ving screened over four th.usand dried specimens of *** and close relatives,we present th. first(h.storical)record of Ch.nese *** infected with.h.speromyces *** suggest th.t *** is a h.storically globally distributed species and h.poth.size th.t(native)infection was lost wh.n *** was introduced in North.America.

关键词：异色瓢虫瓢虫科子囊菌鞘翅目真菌夜蛾攻击干标本

In situ polymerization of poly(3,4-eth.lenedioxyth.oph.ne)protective layer towards stable zinc anode

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Nano Research 2025年第1期18卷 382-394页

作者： Debin Luo Peng Zh.u Xiaowei Lv Panpan Sun Xiaoh.a Sun h.wei zhao College of Materials and Ch.mical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China h.bei Th.ee Gorges Laboratory Yichang 443007China Sch.ol of Ch.mistry Beihang UniversityBeijing 100191China

Aqueous zinc-ion devices are considered promising candidates for energy storage due to th.ir h.gh.safety,low cost and relatively h.gh.energy ***,th. dendrite growth.h.drogen evolution reaction(h.R)and corrosion of th. zinc anode significantly limit th. development of Zn-ion ***,an inexpensive poly(3,4-eth.lenedioxyth.oph.ne)(PEDOT)protective layer was constructed in situ on th. Zn surface using electropolymerization to suppress dendrite growth.and side reactions,th.reby enh.ncing th. reversibility of *** and th.oretical calculations revealed th.t th.s h.droph.lic protective layer promotes th. desolvation process of h.drated Zn^(2+)and facilitates th. transport of zinc ions,th.s improving th. th.rmodynamic and kinetic properties of Zn^(2+)deposition and inh.biting interfacial side ***,th. optimized PEDOT@Zn symmetric battery exh.bited a cycling stability exceeding 1250 h.at 0.5 mA·cm^(-2)and 0.25 mAh.cm^(-2),with.a significantly reduced overpotential(from 91.8 to 35 mV).With.th. assistance of th. PEDOT protective layer,th. PEDOT@Zn//Cu battery maintained approximately 99.5%Coulombic efficiency after 450 ***-situ scanning electron microscopy(SEM)and in situ optical microscopy ch.racterizations furth.r confirmed th.t th. PEDOT protective layer can effectively suppress th. growth.of zinc ***,th. Zn-ion capacitors assembled by th. PEDOT@Zn and activated carbon also demonstrated outstanding cycling stability.

关键词： zinc-ion devices zinc anode poly(3 4-eth.lenedioxyth.oph.ne)(PEDOT) dendrite desolvation process

Wide-gamut lasing from a single organic ch.omoph.re

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Ligh.(Science & Applications) 2018年第1期7卷 115-123页

作者： S.Lane S.Vagin h.Wang W.R.h.inz W.Morrish.y.zhao B.Rieger A.Meldrum Department of Ph.sics University of AlbertaEdmontonAB T6G2E1Canada Department of Ch.mistry Technical University of MunichLichtenbergstraße 485747 Garching bei MünchenGermany

Th. development of wideband lasing media h.s deep implications for imaging,sensing,and display *** sh.w th.t a single ch.omoph.re can be engineered to feature wide-gamut fluorescence and lasing th.ough.ut th. entire visible spectrum and *** exceptional color tuning demonstrates a ch.mically controlled paradigm for ligh. emission applications with.precise color *** such.extensive color control requires a molecular blueprint th.t yields a h.gh.quantum efficiency and a h.gh.solubility in a wide variety of liquids and solids wh.le featuring a h.terocyclic structure with.good steric access to th. lone pair *** th.se requirements in mind,we designed a lasing ch.omoph.re th.t encloses a lasing color space twice as large as th. sRGB *** record degree of color tuning can in principle be adapted to th. solid state by incorporating th. ch.omoph.re into polymer *** appropriately engineering th. base molecular structure,th. widest range of lasing wavelength. observed for a conventional gain medium can be ach.eved,in turn establish.ng a possible route toward h.gh.fficiency ligh. emitters and lasers with.near-perfect ch.omaticity.

关键词： tuning lasing structure

h.rdening and tough.ning effects of intermediate nanosized structures in a confined amorph.us alloy film

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Journal of Materials Science & Tech.ology 2022年第23期118卷 44-53页

作者： Z.Q.Ch.n M.C.Li X.Tong y.zhao J.y.Xie S.W.Guo P.h.ang F.Wang h.B.Ke B.A.Sun W.h.Wang Songsh.n Lake Materials Laboratory Dongguan 523808China Institute of Ph.sics Chinese Academy of SciencesBeijing 100190China Xinjiang Key Laboratory of Solid State Ph.sics and Devices and Sch.ol of Ph.sical Science and Tech.ology Xinjiang UniversityXinjiangUrumqi 830046China Key Laboratory of LCR Materials and Devices of yunnan Province School of Materials and EnergyYunnan UniversityKunming 650091China State-Key Laboratory for Mech.nical Beh.vior of Material Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory for Strength.and Vibration of Mech.nical Structures Xi’an Jiaotong UniversityXi’an 710049China National Demonstration Center for Experimental Mech.nics Education Xi’an Jiaotong UniversityXi’an 710049China

Th. plastic deformation of amorph.us alloys is well known to be localized into sh.ar bands(SBs),wh.ch.are believed to stem from th. atomic-scale flow defects,i.e.,sh.ar transformation zones(STZs).yet,th. bridge between th. mesoscopic SBs and th. atomic-scale STZs remains poorly *** th.s work,th.ough.th.rmally activating pronouncedβrelaxations in th. well-designed crystalline-layer confined amorph.us(CLCA)Ni W alloy films,we experimentally captured and observed an intermediate nanosized structure termed as“nano sh.ar bands”(NSBs)with.a typical size of 1–2 nm in th.ckness and5–10 nm in *** influences of such.NSB structures on th. macroscale deformation beh.vior were systematically *** was found th.t NSBs lead to both.h.rdening and tough.ning effects for th. CLCA films,as th.y promote multiple and controlled sh.ar banding deformation,wh.ch.results in enh.nced *** intermediate NSB structure could connect th. microstructural ch.racteristics and macroscopic plasticity in amorph.us alloys and may provide new insigh.s for understanding th. microscopic deformation mech.nism of amorph.us alloys as well as tuning/designing th.ir properties.

关键词： Amorph.us alloys Nano sh.ar band h.rdening Tough.ning Crystallization

Modeling ocean wave propagation under sea ice covers

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Acta Mech.nica Sinica 2015年第1期31卷 1-15页

作者： Xin zhao h.yley h. Sh.n Sukun Ch.ng Department of Civil and Environmental Engineering Clarkson University

Operational ocean wave models need to work globally, yet current ocean wave models can only treat ice covered regions crudely. Th. purpose of th.s paper is to provide a brief overview of ice effects on wave propagation and different research.meth.dology used in studying th.se effects. Based on its proximity to land or sea, sea ice can be classified as： landfast ice zone, sh.ar zone, and th. marginal ice zone. All ice covers attenuate wave energy. Only long swells can penetrate deep into an ice cover. Being closest to open water, wave propagation in th. marginal ice zone is th. most complex to model. Th. ph.sical appearance of sea ice in th. marginal ice zone varies. Grease ice, pancake ice, brash.ice, floe aggregates, and continuous ice sh.et may be found in th.s zone at different times and locations. Th.se types of ice are formed under different th.rmalmech.nical forcing. Th.re are th.ee classic models th.t describe wave propagation th.ough.an idealized ice cover： mass loading, th.n elastic plate, and viscous layer models. From ph.si cal arguments we may conjecture th.t mass loading model is suitable for disjoint aggregates of ice floes much.smaller th.n th. wavelength. th.n elastic plate model is suitable for a con tinuous ice sh.et, and th. viscous layer model is suitable for grease ice. For different sea ice types we may need different wave ice interaction models. A recently proposed viscoelas tic model is able to synth.size all th.ee classic models into one. Under suitable limiting conditions it converges to th. th.ee previous models. Th. complete th.oretical framework for evaluating wave propagation th.ough.various ice covers need to be implemented in th. operational ocean wave models. In th.s review, we introduce th. sea ice types, previous wave ice interaction models, wave attenuation mech.nisms,th. meth.ds to calculate wave reflection and transmission between different ice covers, and th. effect of ice floe breaking on sh.ping th. sea ice morph.logy. Labora

关键词： Ocean waves Sea ice Cryosph.ric ch.nge