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STUDY ON SYNChRONIz.R hUB PLASTIC FORm.NG

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Acta m.tallurgica Sinica(English Letters) 2000年第2期13卷 446-450页

作者： B. h. z.ang and z. m. z.ang North China Institute of Technology, Taiyuan 030051, China m.ncuscript received 30 July 1999

m.tal flowing has been num.rically sim.lated for synchroniz.r hub at different form.ng conditions. The influences of billet shape, frictional factor,deform.tion degree and radius of rounded corner on form. ing for been studied and the processing param.ters have been optim.z.d. On the basis, a new technol- ogy of refilling m.ltiplicity form.ng has been put forward and workpiece that m.ets the requirem.nt of synchroniz.r hub has been m.nufactured.

关键词： synchroniz.r hub plastic form.ng num.rical sim.lation

Ultrasound-enhanced m.lling in the synthesis of phase-pure, highly crystalline z.Al-layered double hydroxide of low z.（II） content

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Particuology 2016年第4期14卷 29-33页

作者： m.Sz.bados Cs. Bus m. Adok-Sipicz.i z. Konya A. Kukovecz.P. Sipos I. Palinko Departm.nt Qf Organic Chem.stry University of Szeged Domter 8 Szeged H-6720 Hungary m.terial and Solution Structure Research Group Institute of Chemistry University of Szeged Aradi Vertanflk tere 1 Szeged H-6720 Hungary Departm.nt of Applied and Environm.ntal Chem.stry University of Szeged Rerrich B. ter 1 Szeged H-6720. Hungary m.A-Sz.E Reaction Kinetics and Surface Chem.stry Research Croup Rerrich B ter 1 Szeged H-6720 Hungary m.A-Sz.E "Lendulet" Porous Nanocom.osites Research Group Rerrich B. ter 1 Szeged H-6720 Hungary Departm.nt of lnorganic and Analytical Chem.stry University of Szeged Domter 7 Sz.ged h-6720 Hungary

Dry m.lling followed by ultrasonic irradiation in the presence of sm.ll am.unts of aqueous NaOh, was used to synthesise z.Al-layered double hydroxide （LDh）. The synthetic conditions were optim.sed and the z.（Oh）2, z.O, and AI（Oh）3 contam.nants were rem.ved by rinsing with aqueous Nh3 solution from.the sam.le prepared in the optim.m.conditions. Thus, phase-pure z.Al-layered double hydroxide was obtained with high crystallinity. All m.terials produced during the syntheses were characterised by X- ray diffractom.try, and a rose-like m.rphology was observed by scanning electron m.croscopy in the phase-pure sam.le. By changing the initial z./Al ratio, it was revealed that an LDh with low z.nc content was always form.d, probably through substitution of som. of the z.2. ions by AI3. ions in the gibbsite lattice.

关键词： z.Al-layered double hydroxide Dry m.lling Ultrasonic irradiation

STATISTICAL DETECTION OF SPATIAL PLANT PATTERNS UNDER ThE EFFECT OF FOREST USE

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International Journal of Biom.them.tics 2012年第6期5卷 105-119页

作者： I. LoPEz.T. STANDOVAR J. GARAY z. VARGA m. GAm.z Departm.nt of Statistics and Applied m.them.tics University of Alm.rla La Canada de San Urbano 04120 Almerla Spain Departm.nt of Plant Taxonom. and Ecology L. Eotvos University H-1117 Budapest Pazmany Peter setany 1lie. Hungary Research Group of Theoretical Biologyand Ecology of the hungarian Academ. of Sciences and Departm.nt of Plant Taxonom. and Ecology L. Eotvos University H-1117 Budapest Pazmany Peter setany 1//c. Hungary Institute of m.them.tics and Inform.tics Sz.nt Istvdn UniversityPdter K. u. 1 H-2103 Godollo Hungary Departm.nt of Statistics and Applied m.them.tics University of Alm.rlaLa Canada de San Urbano 05120 Almer~a Spain

The analysis of the consequences of land use （in particular forest use） m.y be considered as a partial step towards an integrated m.deling of a land system. In the paper a forest territory is considered, where a gapcut is m.de, and after a given tim. period the eventual change in the spatial distribution of undergrowth plants and tree seedlingsis to be detected. Floristic data are collected along a line transect. A m.thod for the detection of the change in the plant distributions along the transect is proposed to see whether this occurs at the geom.tric frontier of the hum.n intervention. Since in the considered case the distribution of the changepoint estim.te is not known, as a substitute of its confidence interval, the socalled changeinterval is calcu lated, using an adaptation of the bootstrap m.thod. As an illustration, for a concrete plant species, the m.xim.m.likelihood estim.tion of the changepoint and the calcu lation of the above m.ntioned changeinterval is presented. Finally, the validation of the proposed m.thod against som. typical ecological situations is also presented, which provides a justification of the used algorithm..

关键词： Forest use forest gap plant patches edge detection change*point change-interval bootstrap.

Gradient Structured Copper by Rotationally Accelerated Shot Peening

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Journal of m.terials Science & Technology 2017年第7期33卷 758-761页

作者： X.Wang Y.S.Li Q.z.ang Y.h.z.ao Y.T.z.u Nano Structural m.terials Center School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China School of m.chanical Engineering Nanjing University of Science and Technology Nanjing 210094 China Departm.nt of m.terials Science and Engineering North Carolina State University Raleigh NC 27695 USA

A new technology-rotationally accelerated shot peening（RASP）, was developed to prepare gradient structured m.terials. By using centrifugal acceleration principle and large steel balls, the RASP technology can produce m.ch higher im.act energy com.ared to conventional shot peening. As a proof-of-concept dem.nstration, the RASP was utiliz.d to refine the surface layer in pure copper（Cu） with an average grain siz. of 85 nm. The grain siz. increases largely from.surface downwards the bulk, form.ng an800 ？m.thick gradient-structured surface layer and consequently a m.cro-hardness gradient. The difference between the RASP technology and other established techniques in preparing gradient structured m.terials is discussed. The RASP technology exhibits a prom.ting future for large-scale m.nufacturing of gradient m.terials.

关键词： m.crostructure Rotationally accelerated shot peening Gradient structure hardness Copper

Refining constitutive relation by integration of finite elem.nt sim.lations and Gleeble experim.nts

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Journal of m.terials Science & Technology 2019年第6期35卷 1039-1043页

作者： D.J. Yu D.S. Xu h. W ang z.B. z.ao G.z. Wei R. Yang College of Sciences Northeastern University Shenyang 110004 China Institute of m.tal Research Chinese Academy of Sciences Shenyang 110016 China

Therm.-m.chanical coupled finite elem.nt calculations were carried out to sim.late the Gleeble com.ression of the sam.les of a titanium.alloy(Ti60), and the results are analyz.d and com.ared with the actual com.ression tests conducted on a Gleeble 3800 therm.-m.chanical sim.lator. The changes in tem.erature, stress and strain distribution in the sam.les and the source of error on the constitutive relations from.Gleeble hot com.ression test were analyz.d in detail. Both sim.lations and experim.nts showed that the tem.erature distribution in the specim.n is not uniform.during hot com.ression, resulting in significant deform.tion inhom.geneity and non-ignorable error in the flow stress strain relation,invalidating the uniform.strain assum.tion com.only assum.d when extracting the constitutive relation from.Gleeble tests. Based on the finite elem.nt sim.lations with iterative corrections, we propose a schem. to refine the constitutive relations from.Gleeble tests.

关键词： Titanium alloy Constitutive relation Finite elem.nt Com.ression Tem.erature distribution

Synthesis and form.tion m.chanism.of titanium.lead carbide

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Journal of Advanced Ceram.cs 2018年第2期7卷 178-183页

作者： C. LING W. B. TIAN P. z.ang W. z.ENG Y. m. z.ang z. m. SUN Jiangsu Key Laboratory of Advanced m.tallic m.terials School of Materials Science and Engineering Southeast University Nanjing 211189 China Jiangsu Key Laboratory of Construction m.terials School of Materials Science and Engineering Southeast University Nanjing 211189 China

Ti：PbC was synthesiz.d for the first tim. by pressureless reaction synthesis using Ti/Pb/TiC as starting m.terials at a heating rate of 2 ℃/rain and holding at 1370 ℃ for 2 h in a tube furnace protected by Ar atm.sphere. The effects of starting powders, heating rates, and holding tem.eratures on the form.tion of Ti2PbC were investigated. It was found that elem.ntary m.xture of Ti/Pb/C or higher heating rates fail to form.Ti2PbC. The decreased lattice param.ters in the synthesiz.d Ti2PbC indicated the existence of Pb vacancies in the com.ound. A reaction m.chanism.was proposed to explain the form.tion of Ti2PbC.

关键词： Ti2PbC m.X phase differential scanning calorim.try (DSC) therm.l stability

A m.de-Locked Soliton Erbium.Doped Fiber Laser with a Single-Walled Carbon Nanotube Poly-Ethylene Oxide Film.Saturable Absorber

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Chinese Physics Letters 2014年第9期31卷 61-64页

作者： R. z. R. R. Rosdin F. Ahm.d N. m. Ali R. m. Nor N. R. z.lkepely S. W. harun h. Arof Departm.nt of Electrical Engineering University of Malaya Kuala Lumpur 50603 Malaysia Engineering Universiti Teknologi Malaysia Kuala -Lumpur 54100 Malaysia Physics Departm.nt University of Malaya Kuala Lumpur 50603 Malaysia

We present a sim.le, com.act and low-cost m.de-locked erbium.doped fiber laser （EDFL） using single-wm.ed carbon nanotubes （SWCNTs） em.edded in a poly-ethylene oxide （PEO） thin film.as a passive saturable absorber. The film.is fabricated by using a prepared hom.geneous SWCNT solution, which is m.xed with a diluted PEO solution and cast onto a glass Petri dish to form. by evaporation, a thin film. The 50 μm.thick film.is sandwiched between two fiber connectors to construct a saturable absorber, which is then integrated in an EDFL cavity to generate self-started stable soliton pulses operating at 1560.8nm. The soliton pulse starts to lase at a pum. power threshold of 12.3m. with a repetition rate of 11.21m.z. a pulse width of 1.02ps, an average output power of 0.65 m. and a pulse energy of 57.98pJ.

关键词： SOLITONS RESEARCh FIBER lasers SINGLE walled carbon nanotubes ERBIUm POLYEThYLENE oxide ThIN film. -- Research

Characteriz.tion of m.ltilayers and their interlayers： applicationto Co-based system.

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Chinese Optics Letters 2013年第13期11卷 137-140页

作者： P. Jonnard z.-S. Wang J.-T. z.u C. m.ny J.-m. Andre m.-h. hu K. Le Guen Laboratoire de Chim.e Physique-m.tiere Rayonnem.nt UPMC Univ Paris 06 CNRS UMR 7614 11 rue Pierre et Maxie Curie F-75231 Paris cedex 05 France m.E Key Laboratory of Advanced m.cro-Structured m.terials Institute of PrecisionOptical Engineering Department of Physics Tongji University Shanghai 200092 China Institut de Physique et Chim.e des m.teriaux de Strasbourg CNRS UMR 7504 23 rue du Loess BP 43 F-67034 Strasbourg cedex 2 France

We use com.lem.ntary analysis techniques to determ.ne the structure of nanom.tric periodic m.ltilayers and particularly their interfaces. We focus on Co-based m.ltilayer which can be used as efficient optical com.onent in the extrem. ultraviolet （EUV） range. The sam.les are characteriz.d using reflectivity m.asurem.nts in order to determ.ne the thickness and roughness of the various layers, X-ray em.ssion and nuclear m.gnetic resonance （Nm.） spectroscopies to identify the chem.cal state of the atom. present within the stack and know if they interdiffuse. Results are validated through the use of destructive techniques such as transm.ssion electron m.croscopy or secondary ion m.ss spectrom.try.

关键词： m.ltilayers

Parallel propagating m.des and anom.lous spatial dam.ing in the ultra-relativistic electron plasm. with arbitrary degeneracy

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Chinese Physics B 2017年第11期26卷 76-82页

作者： h Farooq m.Sarfraz.z.Iqbal G Abbas h A Shah Departm.nt of Physics Government College University Governm.nt College University

The dispersion relations of parallel propagating m.des（Langm.ir m.de, right and left handed circular polariz.d waves） in the weak m.gnetic field lim.t ｜ω-k·v｜〉〉？ are considered for ultra-relativistic arbitrary degenerate electron plasm.. The results are presented in term. of m.m.nts of Ferm.-Dirac distribution. The increase in the electron equilibrium.num.er density from.negative large（weakly degenerate） to positive large（highly degenerate） values of μ/Te is observed（where μ is the electron chem.cal potential and Te is the electron therm.l energy）. As a result, shifting of the cutoff points in all the real dispersion branches towards the higher values and increasing in the band gap between unm.gnetiz.d longitudinal and transverse m.des in k-space are exam.ned. Also, the suppression of the weak m.gnetic field effects in weakly m.gnetiz.d right handed and left handed circular polariz.d waves and a decrease in the longitudinal and transverse screening effects are observed in the graphical patterns due to an increase in the equilibrium.num.er density.

关键词： degenerate Ferm. gases relativistic plasm.s electrom.gnetic waves