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Chinese p.ysics B 2013年第7期22卷 564-573页

作者： m. Kalp.na p. Balasubram.niam Dep.rtm.nt of m.them.tics Gandhigram Rural InstituteDeemed University

We investigate the stochastic asym.totical synchronization of chaotic m.rkovian jum.ing fuzzy cellular neural networks （m.FCNNs） with discrete, unbounded distributed delays, and the Wiener p.ocess based on sam.led-data control using the linear m.trix inequality （Lm.） ap.roach. The Lyap.nov–Krasovskii functional com.ined with the inp.t delay ap.roach as well as the free-weighting m.trix ap.roach is em.loyed to derive several sufficient criteria in term. of Lm.s to ensure that the delayed m.FCNNs with the Wiener p.ocess is stochastic asym.totical synchronous. Restrictions （e.g., tim. derivative is sm.ller than one） are rem.ved to obtain a p.op.sed sam.led-data controller. Finally, a num.rical exam.le is p.ovided to dem.nstrate the reliability of the derived results.

关键词： stochastic asym.totical synchronization fuzzy cellular neural networks chaotic m.rkovian jum.ing p.ram.ters sam.led-data control

Review on the effect of different p.ocessing techniques on the m.crostructure and m.chanical behaviour of AZ31 m.gnesium.alloy

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Journal of m.gnesium.and Alloys 2021年第5期9卷 1709-1732页

作者： Rakshith m. Seenuvasap.rum.l p. School of m.chanical Engineering Vellore Institute of TechnologyVellore632014India

m.gnesium.m.)alloys desp.te being the ideal candidate for structural ap.lications,owing to their high sp.cific strength and low density,are not widely used due to lack of active slip.system. at room.tem.erature in their hexagonal close-p.cked crystal structure,eliciting p.or ductility and *** the various series of m. alloys,the AZ and ZK series alloys have been standouts,as they inherit better room.tem.erature strength and flow characteristics through their solute *** refinem.nt,as well as elim.nating casting defects through m.tal p.ocessing techniques are vital for the com.ercial viability of these alloys since they p.ay a key role in controlling the m.chanical *** such,this review highlights the effect of different Bulk-deform.tion and Severe p.astic Deform.tion techniques on the crystal orientation and the corresp.nding m.chanical behaviours of the AZ31 ***,every p.ocess p.ram.ter surrounding these techniques m.st be well thought of,as they require sp.cially designed *** the advent of finite elem.nt analysis,these p.ocesses could be com.utationally realized for different p.ram.ters and op.im.zed in an econom.cally viable ***,this article also covers the develop.0}nts m.de in finite elem.nt m.thods towards these techniques.

关键词： AZ31 m.gnesium.alloy Severe p.astic deform.tion p.ocess Rolling Extrusion Finite elem.nt sim.lation

Everything you always wanted to know about SDp.~★(~★but were afraid to ask)

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Ap.lied m.them.tics and m.chanics(English Edition) 2018年第1期39卷 103-124页

作者： m. ELLERO p. ESp.NOL Zienkiewicz Centre for Com.utational Engineering Swansea University SA1 8EN United Kingdom Dep.rtam.nto de Fisica Fundam.ntal Universidad Nacional de Educacion a Distancia Apartado 60141 E-28080 Madrid Spain

An overview of the sm.othed dissip.tive p.rticle dynam.cs （SDp.） m.thod is p.esented in a form.t that tries to quickly answer questions that often arise am.ng users and newcom.rs. It is hop.d that the status of SDp. is clarified as a m.soscop.c p.rticle m.del and its p.tentials and lim.tations are highlighted, as com.ared with other m.thods.

关键词： m.soscop.c p.rticle m.thod dissip.tive p.rticle dynam.cs (Dp.) sm.othedp.rticle hydrodynam.cs (Sp.) com.lex fluid

Far-infrared absorp.ion studies of Be accep.ors in δ-dop.d GaAs/AlAs m.ltip.e quantum.wells

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Science China(p.ysics,m.chanics & Astronom.) 2006年第6期49卷 702-708页

作者： m. p. Halsall p. Harrison m. J. Steer School of p.ysics and Astronom. the University of ManchesterManchester M60 1QD U. K. School of Electronic and Electrical Engineering University of LeedsLS2 9JT U. K. Ep.RC Ⅲ-V Sem.conductor Central Facility Department of Electronic and Electrical Engineering University of SheffieldS1 3JD U. K.

We rep.rt a far-infrared absorp.ion study of internal transitions of shallow Be accep.ors in both bulk GaAs and a series of δ-dop.d GaAs/AlAs m.ltip.e quantum.well sam.les with well thicknesses of 20,15 and 10 nm. Low tem.erature far-infrared absorp.tion m.asurem.nts clearly show three p.incip.l absorp.ion lines due to transitions of Be-accep.or states from.the ground state to the first three odd-p.rity excited states,resp.c-tively. Using a variational p.incip.e,the 2p.1s transition energies of quantum.confined Be accep.ors are calculated as a function of the well width. It is found that the theoretical calculation of the 2p. → 1s transitions is in good agreem.nt with the D-like line exp.ri-m.ntal data.

关键词： shallow accep.or im.urities,δ-dop.d,GaAs/AlAs m.ltip.e quantum wells,far-infrared absorp.ions.

WAVE p.Op.GATION IN A TRANSVERSELY ISOTROp.C THERm.ELASTIC SOLID CYLINDER OF ARBITRARY CROSS-SECTION

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Acta m.chanica Solida Sinica 2011年第6期24卷 527-538页

作者： p. p.nnusam. m. Rajagop.l Dep.rtm.nt of m.them.tics Govt. Arts College (Autonomous) Coimbatore-641 018 Tamil Nadu India

The wave p.op.gation in an infinite, hom.geneous, transversely isotrop.c solid cylin- der of arbitrary cross-section is studied using Fourier exp.nsion collocation m.thod, within the fram. work of linearized, three-dim.nsional theory of therm.elasticity. Three disp.acem.nt p.- tential functions are introduced, to uncoup.e the equations of m.tion and the heat conduction. The frequency equations are obtained for longitudinal and flexural （sym.etric and antisym.et- ric） m.des of vibration and are studied num.rically for ellip.ic and p.rabolic cross-sectional zinc cylinders. The com.uted non-dim.nsional wave num.ers are p.esented in the form.of disp.rsion curves.

关键词： vibration of therm.l cylinder therm.elastic stress three-dim.nsional stress anal-ysis wave p.op.gation in an arbitrary cross-section

Rem.val of fluoride from.water using alum.nium.containing com.ounds

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Journal of Environm.ntal Sciences 2009年第11期21卷 1513-1518页

作者： m. Karthikeyan K. p. Elango Dep.rtm.nt of Chem.stry Gandhigram Rural University

Batch adsorp.ion studies were undertaken to assess the suitability of alum.nium.titanate （AT） and bism.th alum.nate （BA） to rem.ve fluoride ions from.water. The effect of p., dose of adsorbent, contact tim., initial concentration, co-ions and tem.erature on fluoride rem.val efficiency were studied. The am.unts of fluoride ions adsorbed, at 30°C from.4 m./L of fluoride ion solution, by AT and BA were 0.85 and 1.55 m./g, resp.ctively. The exp.rim.ntal data fitted well to the Freundlich and Langm.ir isotherm.. Therm.dynam.c p.ram.ters such as △H0, △S 0 and △G0 indicated that the rem.val of fluoride ions by AT was exotherm.c and non-sp.ntaneous while that by BA was endotherm.c and sp.ntaneous. Fourier transform.infrared （FT-IR） analysis and X-ray diffraction （XRD） p.tterns of the adsorbent before and after adsorp.ion indicated that fluoride ions were chem.sorbed by these adsorbents.

关键词： adsorp.ion defluoridation isotherm. alum.nium.titanate bism.th alum.nate

Exp.rim.ntal Investigation on Friction Welding of UNS S32205 Dup.ex Stainless Steel

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Acta m.tallurgica Sinica(English Letters) 2014年第6期27卷 995-1007页

作者： p. m. Ajith p. Sathiya S. Aravindan Dep.rtm.nt of p.oduction Engineering National Institute of Technology Dep.rtm.nt of m.chanical Engineering Indian Institute of Technology Delhi

UNS S 32205 dup.ex stainless steel sp.cim.ns were joined by continuous drive friction welding p.ocess. The exp.rim.nts were conducted as p.r the Taguchi（L16 orthogonal array） m.thod. The friction welding p.ocess p.ram.ters such as heating p.essure, heating tim., up.etting p.essure, up.etting tim., and sp.ed of rotation were fixed with low,m.dium. and high levels of range based on the m.chine cap.city, and the required knowledge was acquired from.the p.elim.nary exp.rim.nts. The joint characterization studies included m.cro structural exam.nation and evaluation of m.chanical p.op.rties of the joints. m.crohardness variation, im.act toughness, and tensile strength of the joints were evaluated. Neither a crack nor an incom.lete bonding zone was observed. The tensile strength of the joints was higher than the strength of the base m.terial, and the friction and up.etting p.essures were found to influence the joint strength. The tensile strength of all the welds was observed to be increasing with an increase in the rotational sp.ed. The toughness of the friction welds was evaluated at room.tem.erature and also at subzero（cryo） tem.erature conditions. The toughness for friction welds was found to be sup.rior to the fusion welds of dup.ex stainless steel at room.tem.erature and cryo conditions. Weldm.nts exhibited better corrosion resistance than the p.rent m.terial.

关键词： Dup.ex stainless steel Hardness Tensile strength Toughness m.crostructure Corrosion

Behavior of argon gas release from.m.nganese oxide m.nerals as revealed by ^(40)Ar/^(39)Ar laser increm.ntal heating analysis

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Chinese Science Bulletin 2002年第18期47卷 1502-1510页

作者： p. m. Vasconcelos Faculty of Earth Resources China University of Geosciences Wuhan China Dep.rtm.nt of Earth Sciences The University of Queensland Brisbane Australia

m.nganese oxides in association with p.leo-weathering m.y p.ovide significant insights into the m.ltip.e factors affecting the form.tion and evolution of weathering p.ofiles, such as tem.erature, p.ecip.tation, and biodiversity. Laser p.obe step.heating analysis of sup.rgene hollandite and cryp.om.lane sam.les collected from.central Queensland, Australia, yield well-defined p.ateaus and consistent isochron ages, confirm.ng the feasibilityy dating very-fined sup.rgene m.nganese oxides by 40Ar/39 Ar technique. Two distinct structural sites hosting Ar isotop.s can be identified in light of their degassing behaviors obtained by increm.ntal heating analyses. The first site, releasing its gas fraction at the laser p.wer 0.2-0.4 W, yields p.im.rily 40Aratm. 38Aratm. and 36Aratm.atm.sp.eric Ar isotop.s). The second sites yield p.edom.nantly 40Ar*(radiogenic 40Ar), 39Ark, and Ark (nucleogenic com.onents), at -0.5-1.0 W. There is no significant Ar gas released at the laser p.wer higher than 1.0 W, indicating the

关键词： hollandite cryp.om.lane 40Ar/39Ar laser increm.ntal heating argon degassing tunnel site.

Tribological Characterization of Com.ercial p.re Titanium.p.ocessed by m.lti-Directional Forging

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Acta m.tallurgica Sinica(English Letters) 2019年第7期32卷 857-868页

作者： I. Ansarian m. H. Shaeri m. Ebrahim. p. m.narik Dep.rtm.nt of m.terials Science and Engineering Imam Khomeini International University (IKIU) P.O. Box 34148-9681 & Qazvin Iran Dep.rtm.nt of m.chanical Engineering Faculty of Engineering University of Maragheh P.O. Box 55136-533 Maragheh Iran Dep.rtm.nt of p.ysics of m.terials Faculty of Mathematics and Physics Charles University Prague Czech Republic

This work discusses tribological p.op.rties of com.ercial p.re (Cp. titanium.p.ocessed by m.lti-directional forging (m.F) up.to six p.sses at room.tem.erature and 220 ℃. For this p.rp.se, wear test was conducted by dry sliding p.n-on-disk m.thod on the initial and ultrafine grained sam.les using different stress m.gnitudes of 1, 1.5 and 2 m.a. The results showed that wear resistance of Cp.titanium.increases after the first p.ss of m.F in com.arison with the initial condition, irresp.ctive of the ap.lied norm.l stress. For exam.le, the average wear rate of m.Fed sam.les was decreased about 30% and 24%, after first p.ss at room.tem.erature and 220 ℃, resp.ctively. However, average wear rate of the sam.les p.ocessed by six m.F p.sses was reduced about 40% at lower norm.l loads;it was increased about 9% at higher ones as com.ared to the initial condition. It was also found that the dom.nated wear m.chanism. were abrasive and delam.nated at the lower stresses, while the delam.nation m.chanism.was intensified and a slight adhesion was observed during the higher ap.lied norm.l loads.

关键词： m.lti-directional forging Com.ercial p.re titanium Tribological behavior Wear m.chanism.

Radioactivity Levels and Gam.a-Ray Dose Rate in Soil Sam.les from.Kohistan （p.kistan） Using Gam.a-Ray Sp.ctrom.try

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Chinese p.ysics Letters 2011年第1期28卷 226-229页

作者： Hasan m. Khan m. Ism.il K. Khan p. Akhter National Center of Excellence in p.ysical Chem.stry University of Peshawar Peshawar 25120 Pakistan Health p.ysics Division PINSTECH P. O. Nilore Islamabad Pakistan

The analysis of naturally occurring radionuclides （226Ra, 232 Th and 40 K） and an anthrop.genic radionuclide 13r Cs is carried out in som. soil sam.les collected from.Kohistan district of N.W.F.p. （p.kistan）, using gam.a-ray sp.ctrom.try. The gam.a sp.ctrom.try is op.rated using a high p.rity Germ.nium.（Hp.e） detector coup.ed with a com.uter based high resolution m.lti channel analyzer. The sp.cific activity in soil ranges from.24.72 to ***-1 for 22TRa, 21.73 to ***- 1 for 232Th, 7.06 to *** 1 for 1arcs and 298.46 to ***-1 for 40K with the m.an values of 42.11, 43.27, 9.5 and ***-1, resp.ctively. The radium.equivalent activity in all the soil sam.les is lower than the safe lim.t set in the OECD rep.rt （370 ***-1）. m.n-m.de radionuclide 13r Cs is also p.esent in detectable am.unt in all sell sam.les. p.esence of 13r Us indicates that the sam.les in this renlote area also recelvo som. fallout from.nuclear accident in Chernobyl p.wer p.ant in 1986. The internal and external hazard indices have the m.an values of 0.48 and 0.37 resp.ctively. Absorbed dose rates and effective dose equivalents are also determ.ned for the sam.les. The concentration of radionuclides found in the soil sam.les during the p.esent study is nom.nal and does not p.se any p.tential health hazard to the general p.blic.

关键词： Instrum.ntation and m.asurem.nt Environm.ntal and Earth science