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Study on Single-fiber Pull-out Meth.d for Evaluating Interfacial Strength.in CFRP

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h.gh.Tech.ology Letters 1995年第1期1卷 105-108页

作者： Yudong, h. zhiqian, zh. Lixun, L. Qiwei, L. h.rbin Inst of Tech.ology Harbin China

Single-fiber pull-out testing (SFPOT) meth.ds are frequently used to evaluate th. interfacial adh.sion between fiber and matrix in composite materials. To make such.pull-out measurements, h.wever, th. length.of embedded fiber must be small enough.so th.t th. fiber does not break before it is pulled freely. Th.s is difficult to ach.eve by conventional meth.ds with.fibers of small diameter, such.as th. carbon fibers. In th.s paper, a fiber pull-out experiment is described. Specialized apparatus in our laboratory, as well as th.s tech.ique for sample preparation are discussed in detail. Th. interfacial sh.ar strength.of carbon fiber/resin matrix composites is analyzed quantitatively by using th. finite-element meth.d. Th. SFPOT system h.s been proved to be an available means for th. study of interfacial properties for carbon fiber/resin matrix composites.

关键词： Carbon fiber Composite materials Interfacial sh.ar strength Single-fiber pull-out

Th. Ph.ton Polarization Parameter of 2h.n, γ）3h.reaction with.Inclusion of th. Electric Quadrupole Contribution

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Ch.nese Ph.sics Letters 2014年第9期31卷 32-35页

作者： h. Sadegh. M. Mosavi-Kh.nsari Department of Ph.sics Faculty of Science Arak University Arak 8349-8-38156 Iran

We use effective field th.ory （EFT） for th. calculation of neutron-deuteron radiative capture at very low energies. We present h.re th. use of EFT to calculate a low-energy ph.to-nuclear observable in th.ee-body systems, th. ph.ton polarization parameter and and fore-aft asymmetry at th.rmal neutron energies up to next-to-next to leading order （N2 LO）, with.inclasion of th. electric quadrupole contribution. Th. ph.ton polarization parameter in total is found to be Rc = -0.421±0.003 and is in good agreement with.th. oth.r modern th.oretical calculations based on modern nucleon-nucleon potentials. In comparison with.our previous work, a satisfactory agreement with.th. available experimental data is found by inclusion of th. electric quadrupole contribution.

关键词： Ph.TONS -- Polarization RESEARCh FIELD th.ory (Ph.sics) NEUTRON-deuteron interactions QUADRUPOLES Th.EE-body problem (Ph.sics)

Fabrication of Silicon Quantum Wires by Conventional Silicon Processing

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h.gh.Tech.ology Letters 1995年第1期1卷 25-27页

作者： Yi, Sh. Jianlin, L. Feng, W. Rong, zh. Ping, h. Sh.lin, G. Sh.nming, zh. Baoh.a, M. Youdou, zh. Nanjing Univ Nanjing China

Ultra fine silicon quantum wires with.th. Si/SiO2 h.terointerface h.ve been fabricated successfully by using reactive ion etch.ng, anisotropic wet ch.mical etch.ng and subsequent th.rmal oxidation. Th. cross-sectional image of scanning electron microscope sh.ws th. silicon quantum wires of h.gh.quality with.th. linewidth.down to 20nm. Th. present meth.d h.s many remarkable advantages, wh.ch.is important to th. study of low-dimension quantum ph.sics and devices.

关键词： Quantum wire Silicon Silicon dioxide Silicon tech.ique

Selective De-O-acetylation in TCP-containing Carboh.drate Structures with.Magnesium Meth.xide

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Ch.nese Ch.mical Letters 2000年第11期11卷 941-944页

作者： Qin, zh Li, h.Cai, MS Li, ZJ Beijing Med Univ Sch Pharmaceut Sci Dept Bioorgan Chem Beijing 100083 Peoples R China

Magnesium meth.xide can be used for TCP-containing substrates to remove acetyl group successfully wh.le leaving th. TCP-group virtually intact.

关键词： OCh TCP De

Computational Research.on Modular Undulating Fin for Biorobotic Underwater Propulsor

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Journal of Bionic Engineering 2007年第1期4卷 25-32页

作者： Yong-h.a zhang Lai-bing Jia Sh.-wu zhang Jie Yang K. h. Low Dept of Precision Mach.nery and Precision Instrumentation University of Science and Technology of China Hefei 230026 P. R. China Sch.ol of Mech.nical and Aerospace Engineering Nanyang Technological University 639798 Singapore

Biomimetic design employs th. principles of nature to solve engineering problems. Such.designs wh.ch.are h.ped to be quick, efficient, robust, and versatile, h.ve taken advantage of optimization via natural selection. In th. present research. an environment-friendly propulsion system mimicking undulating fins of stingray was built. A non-conventional meth.d was considered to model th. flexibility of th. fins of stingray. A two-degree-of-freedom mech.nism comprised of several linkages was designed and constructed to mimic th. actual flexible fin, Th. driving linkages were used to form a mech.nical fin consisting of several fin segments, wh.ch.are able tO produce undulations, similar to th.se produced by th. actual fins. Owing to th. modularity of th. design of th. mech.nical fin, various undulating patterns can be realized. Some qualitative observations, obtained by experiments, predicted th.t th. th.usts produced by th. mech.nical fin are different among various undulating patterns. To fully understand th.s experimental ph.nomenon is very important for better performance and energy saving for our biorobotic underwater propulsion system. h.re, four basic undulating patterns of th. mech.nical fin were performed using two-dimensional unsteady computational fluid dynamics （CFD） meth.d. An unstructured, grid-based, unsteady Navier-Stokes solver with.automatic adaptive re-mesh.ng was used to compute th. unsteady flow around th. fin th.ough.twenty complete cycles. Th. pressure distribution on fin surface was computed and integrated to provide fin forces wh.ch.were decomposed into rift and th.ust. Th. pressure force and friction force were also computed th.ough.ut th. swimming cycle. Finally, vortex contour maps of th.se four basic fin undulating patterns were displayed and compared.

关键词： biomimetic modular undulating fin biorobotic AUV CFD propulsion efficiency

From Reactivity and Regioselectivity to Stereoselectivity: An Odyssey of Designing PIP Amine and Related Directing Groups for C-h.Activation

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Ch.nese Journal of Ch.mistry 2019年第7期37卷 647-656页

作者： Qi zhang bing-Feng Sh. Department of Ch.mistry Zhejiang University Hangzhou Zhejiang 310027 China

Wh.t is th. most favorite and original ch.mistry developed in your research.group? Developing PIP amine for regio-and enantioselective meth.lene C-h.activation. h.w do you get into th.s specific field? Could you pleas... 详细信息

关键词： Regioselectivity Stereoselectivity

Th. W-11-4A Platform Compreh.nsive Strength.Monitoring System

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Ch.na Ocean Engineering 1998年第2期13卷 135-146页

作者： Sh.n, zh Li, h.Xue, YI Ch.n, JC zhao, Q Ch.nese Acad Sci Inst Mech Beijing 100080 Peoples R China Louisiana Tech.Univ Appl & Computat Anal & Modeling Program Ruston LA 71272 USA Acad Sinica S China Sea Inst Oceanol Guangzhou 510301 Peoples R China

A compreh.nsive strength.monitoring system used on a fixed jacket platform is presented in th.s paper. Th. long-term monitoring of W-11-4A platform ach.eved. Structural responses (strain and acceleration) at selected locations, as well as associated environmental parameters, h.ve been obtained. Th. emph.sis of th. paper is placed on th. system design, and th. instrumentation and operation meth.dology employed in th. monitoring of th. structural responses. Th. performance of th. system and th. ch.racteristic results obtained during its 13-month.operation are also summarized.

关键词： monitoring tech.iques compreh.nsive strength.monitoring structural responses waterproof strain transducers underwater instrumentation tech.iques

SUBSTRUCTURE PRECONDITIONERS FOR NONCONFORMING PLATE ELEMENTS

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Journal of Computational Math.matics 1998年第4期16卷 289-304页

作者： Sh., ZC Xie, zh Ch.nese Acad Sci ICMSEC State Key Lab Sci & Engn Comp Beijing 100080 Peoples R China Ch.nese Acad Sci Inst Atmospher Phys LASG Beijing 100080 Peoples R China

In th.s paper, we consider th. problem of solving finite element equations of bih.rmonic Dirich.et problems. We divide th. given domain into non-overlapping subdomains, construct a preconditioner for Morley element by substructuring on th. basis of a function decomposition for discrete bih.rmonic functions. Th. function decomposition is introduced by partitioning th.se finite element functions into th. low and h.gh.frequency components th.ough.th. intergrid transfer operators between coarse mesh.and fine mesh. and th. conforming interpolation operators. Th. meth.d leads to a preconditioned system with.th. condition number bounded by C(1 + log(2) h.h. in th. case with.interior cross points, and by C in th. case with.ut interior cross points, wh.re h.is th. subdomain size and h.is th. mesh.size. Th.se tech.iques are applicable to oth.r nonconforming elements and are well suited to a parallel computation.

关键词： substructure preconditioner bih.rmonic equation nonconforming plate element

Ph.logeograph. of h.gh.y Path.genic h. Avian Influenza Viruses in Ch.na

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Virologica Sinica 2020年第5期35卷 548-555页

作者： Xiaowen Li Xueying Li bing Xu Department of Earth.System Science Tsinghua UniversityBeijing 100084China Center for h.alth. Cities Institute for China Sustainable UrbanizationTsinghua UniversityBeijing 100084China

Th. spread of h. h.gh.y path.genic avian influenza viruses poses serious th.eats to th. poultry industry,wild bird ecology and h.man *** of h. viruses between poultry and wild birds is a significant public h.alth.th.eat in ***,viral migration networks in th.s region need to be urgently ***,we conducted molecular genetic analyses of th. h.magglutinin genes of h. h.gh.y path.genic avian influenza viruses in multiple h.sts from 2000 to 2018 in *** aim was to clarify th. roles of different h.sts in th. evolution of h. *** used a flexible Bayesian statistical framework to simulate viral space diffusion and continuous-time Markov ch.ins to infer th. dynamic evolutionary process of spatiotemporal *** ph.logeograph.c analysis of h. viruses sh.wed for th. first time th.t h. viruses in poultry and wild birds were present in Guangdong ***,Guangdong,Jiangsu,Sh.ngh.i and h.nan acted as th. epicenters for th. spread of various h. subtypes viruses in poultry,and h.nan,Sh.ngh.i,h.ng Kong and Inner Mongolia acted as epicenters for th. spread of various h. subtypes viruses in wild ***,h. viruses exh.bited distinct evolutionary dynamics in poultry and wild *** findings extend our understanding of th. transmission and spread of h.gh.y path.genic h. avian influenza viruses in Ch.na.

关键词： Influenza h. viruses Ph.logeograph. Spatial dispersion Population dynamics Ch.na