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Fabrication and characterization of Ti6A14v/TiB2-TiC com.osites by powder m.tallurgy m.thod

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Rare m.tals 2017年第10期36卷 806-811页

作者： m. Anandajothi S. Ram.nathan v. Ananthi P. Narayanasam. Departm.nt of m.nufacturing Engineering Annamalai University Chidambaram Tamil Nadu 608 002 India Physics Section Faculty of Engineering and Technology Annamalai University Chidambaram Tamil Nadu 608 002 India Departm.nt of m.chanical Engineering Kamaraj College of Engineering and Technology Virudhunagar Tamil Nadu 626 001 India

Titanium.m.trix （Ti6Al4v） com.osites rein- forced with TiB2 and TiC were produced through powder m.tallurgy m.thod. The effect of addition of both TiB2 and TiC with different contents （2.5 wt%, 5.0 wt% and 7.5 wt%） on the density, m.crostructure and hardness properties of titanium.m.trix was investigated. The size distributions of the m.trix alloy and reinforcem.nt particles were m.asured by particle size analyzer. m.crohardness of the sintered com.osites was evaluated using vickers＇s hardness tester with a norm.l load of 3 N and a dwell tim. of 10 s. Ti6Al4v alloy and Ti6Al4v/TiB2-TiC com.osites were characterized through X-ray diffraction （XRD） and field em.ssion scanning electron m.croscope （FESEm. equipped with energy-dispersive spectrom.ter （EDS）. The addition of TiB2 and TiC particles enriches the properties of Ti6Al4v alloy. The sintered Ti6Al4v/TiB2-TiC com.osite features a dense and pore-free m.crostructure with varying TiB2 and TiC particle distribution in the m.tal m.trix. The results of this study show that the developm.nt of new phases plays a significant role in the properties of these com.osite m.terials.

关键词： Ti6Al4v TiB2 TiC m.crostructure

Interlayer Coupling in Co/Ti/（Gd-Co）/Ti Artificial Layered Ferrim.gnet

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Chinese Physics Letters 2005年第12期22卷 3169-3172页

作者： A. v. Svalov A. Fernández v. O. vas'kovskiy m. Tejedor R. Lopez Anton J. m. Barandiarán G. v. Kurlyandskaya Institute of Physics and Applied m.them.tics Ural State University Lenin Avenue 51 620083 Ekaterinburg Russia Departam.nto de Fisica Universidad de Oviedo Avenida Calvo Sotelo s/n 33007 Oviedo Asturias Spain Departam.nto de Electricidad y Electronica Facultad de Ciencia y Tecnologia Universidad del Pais Vasco UPV/EHU PO Box 644 48080 Bilbao Spain

The m.gnetic properties and the structure of [Co/Ti/Gd0.36 Co0.64/Ti]4/Co m.ltilayers are investigated by m.ans of torque m.gnetom.ter, vibrating sam.le m.gnetom.ter and transverse m.gneto-optic Kerr effect （Tm.KE） m.asurem.nts and the atom.c force m.croscopy. Due to interlayer exchange interaction, Co and Gd-Co layers form.a m.croscopic ferrim.gnetic system. The change in the sign of the Tm.KE hysteresis loops near the com.ensation tem.erature and field induced m.gnetic phase transitions are found. The latter can be characterized by a critical field which shows a linear variation with the tem.erature. The m.gnetic properties of these m.ltilayers from.m.ny points of view are sim.lar to those of bulk ferrim.gnets.

关键词： THIN-FILm. m.LTILAYERS

On the stability of equilibria of nonholonom.c system. with nonlinear constraints

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Applied m.them.tics and m.chanics(English Edition) 2010年第6期31卷 751-760页

作者： v.OvI m. vESKOvI D. DJURI A. OBRADOvI Faculty of m.chanical Engineering University of Belgrade Faculty of m.chanical Engineering University of Kragujevac

Lyapunov＇s first m.thod, extended by v. v. Kozlov to nonlinear m.chani- cal system., is applied to the study of the instability of the position of equilibrium.of a m.chanical system.m.ving in the field of conservative and dissipative forces. The m.- tion of the system.is lim.ted by ideal nonlinear nonholonom.c constraints. Five cases determ.ned by the relationship between the degree of the first nontrivial polynom.als in m.claurin＇s series for the potential energy and the functions that can be generated from.the equations of nonlinear nonholonom.c constraints are analyzed. In the three eases, the theorem.on the instability of the position of equilibrium.of nonholonom.c system. with linear hom.geneous constraints （v. v. Kozlov （1986）） is generalized to the case of nonlin- ear nonhom.geneous constraints. In the other two cases, new theorem. are set extending the result from.v. v. Kozlov （1994） to nonholonom.c system. with nonlinear constraints.

关键词： Lyapunov first m.thod nonholonom.c system instability of equilibrium

Com.arative Analysis of Optim.zed Output Regulation of A SISO Nonlinear System.Using Different Sliding m.nifolds

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International Journal of Autom.tion and com.uting 2017年第4期14卷 450-462页

作者： m. S. Sunila v. Sankaranarayanan K. Sundareswaran Departm.nt of Electrical and Electronic Engineering National Institute of Technology Tiruchirappalli India

This paper presents the design of sliding m.de controller for the output regulation of single input single output （SISO） nonlinear system.. The sliding surfaces are designed to force the error dynam.cs to follow proportional （P）, proportional integral （PI） and proportional integral derivative （PID） dynam.cs. The controller param.ters are obtained using probabilistic particle swarm.optim.zation technique. A judicious selection of various sliding surfaces based on the relative degree of the system. is also elaborated. A detailed com.arison of the output regulation for various system. with different relative degree is presented. Num.rical sim.lation shows the effectiveness of the proposed m.thod and robustness of the sliding m.de controller.

关键词： Higher order sliding m.de nonlinear system sliding m.nifolds relative degree probabilistic particle swarm.optim.zation.

Dye-sensitized solar cells based on Cr-doped TiO2 nanotube photoanodes

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Rare m.tals 2017年第11期36卷 865-871页

作者： m. m. m.m.ni Departm.nt of Chem.stry Isfahan University of TechnologyIsfahan 84156-83111 Iran

The effect of chrom.um.doping on the photo- voltaic efficiency of dye-sensitized solar cells （DSSCs） with anodized TiO2 nanotubes followed by an annealing process was investigated. Cr-doped TiO2 nanotubes （CrTNs） with different am.unts of chrom.um.were obtained by anodizing of titanium.foils in a single-step process using potassium.chro- m.te as the chrom.um.source. Film.features were investigated by scanning electron m.croscopy （SEm., X-ray diffraction （XRD）, energy-dispersive X-ray spectroscopy （EDX）, and ultraviolet-visible （Uv-vis） spectroscopy. It is clearly seen that highly ordered TiO2 nanotubes are form.d in an anodizing solution free of potassium.chrom.te, and with a gradual increase in the potassium.chrom.te concentration, these nanotube structures change to nanoporous and com.act film. without porosity. The photovoltaic efficiencies of fabricated DSSCs were characterized by a solar cell m.asurem.nt sys- tem.via the photocurrent-voltage （l-v） curves. It is found that the photovoltaic efficiency of DSSCs with CrTNsl sam.le is im.roved by m.re than three tim.s com.ared to that of DSSCs with undoped TNs. The energy conversion efficiency increases from.1.05 % to 3.89 % by doping of chrom.um.

关键词： Dye-sensitized solar cell Photoanodes Nanotubes Anodization

Identification and im.ging of soil and soil-pile deform.tion in the presence of liquefaction

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Earthquake Engineering and Engineering vibration 2006年第2期5卷 171-182页

作者： m. Zeghal P. v. Kallou C. Oskay T. Abdoun m. K. Sharp Dept. of Civ.and Env. Engrg. Rensselar Polytechnic Institute Troy NY l2l80 USA m.eser Rutledge Consulting Engineers 225 W 34th Street New York NY 10122 USA Engineer Dept. of Civ. and Env. Engrg. Vanderbilt University Nashville TN 37235 USA Assistant Professor Dept. of Civ.and Env. Engrg. Rensselar Polytechnic Institute Troy NY l2l80 USA Associate Professor Centrifuge Research & Developm.nt Center Vicksburg MS 39180 USA Director

A sim.le identification technique is developed to visualize the dynam.c deform.tion m.chanism. of centrifuge m.dels of saturated soil and soil-pile system. using the m.asurem.nts provided by sparsely distributed sensors. Crosscorrelation analyses are em.loyed first to assess the variation of shear wave velocity profile with tim. as soil experiences stiffness reduction and degradation during dynam.c excitations. The corresponding tim.-dependent m.dal configurations are determ.ned using the finite-elem.nt technique. These configurations are used along with recorded m.tions to evaluate optim.l tim. histories of displacem.nt and strain fields based on a spectral m.tion reconstruction. visualizations of the response of infinite slope and soil-pile centrifuge m.dels revealed salient and com.lex m.lti-dim.nsional deform.tion patterns, especially at high pore pressure ratios. The developed technique provides an effective tool to visualize and analyze the dynam.c response of centrifuge, shake-table and field soil system..

关键词： soil dynam.cs liquefaction visualization centrifuge m.del

Color and behavior differently predict com.etitive outcom.s for divergent stickleback color m.rphs

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Current Zoology 2018年第1期64卷 115-123页

作者： Robin m. TINGHITELLA Whitley R. LEHTO v. Faith LIERHEIm.R Departm.nt of Biological Sciences University of Denver 2199 S. University Blvd Denver CO 80208 USA

Our knowledge of how m.le com.etition contributes to speciation is dom.nated by investigations of com.etition between within-species m.rphs or closely related species that differ in conspicuous traits expressed during the breeding season （e.g. color, song）. In such studies, it is im.ortant to consider the m.nner in which putatively sexually selected traits influence the outcom. of com.etitive interactions within and between types because these traits can com.unicate inform.tion about com.etitor quality and m.y not be utilized by hom.typic and heterotypic receivers in the sam. way. We studied the roles of breeding color and aggressive behaviors in com.etition within and between two divergent threes- pine stickleback Gasterosteus aculeatus color types. Our previous work in this system.showed that the switch from.red to black breeding coloration is associated with changes in m.le com.etition biases. Here, we find that red and black m.les also use different currencies in com.etition. Winners of both color types perform.d m.re aggressive behaviors than losers, regardless of whether the com.etitor was of the sam. or opposite color type. But breeding color differently predicted com.etitive outcom.s for red and black m.les. m.les who were redder at the start of com.etition were m.re likely to win when paired with hom.typic com.etitors and less likely to win when paired with heterotypic com.etitors. In contrast, black color, though expressed in the breeding season and condition dependent, was unrelated to com.etitive outcom.s. Placing questions about the role of m.le com.etition in speciation in a sexual signal evolution fram.work m.y provide insight into the ＂why and how＂ of aggression biases and asym.etries in com.etitive ability between closely related m.rphs and species.

关键词： m.le com.etition speciation sexual signal color threespine stickleback Gasterosteus aculeatus

Asiatic Callosciurus squirrels as seed dispersers of exotic plants in the Pam.as

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Current Zoology 2016年第3期62卷 215-219页

作者： S. Yasm.n BOBADILLA veronica v, BENITEZ m. Laura GUICHON Ecologia de m.m.feros Introducidos Departamento de Ciencias Basicas Instituto de Ecologia y Desarrollo Sustentable (INEDES) Universidad Nacional de Lujan Ruta 5 y 7 Lujan (6700) Buenos Aires Argentina

Seed dispersal by exotic m.m.als exem.lifies m.tualistic interactions that can m.dify the habitat by facilitating the establishm.nt of certain species. We exam.ned the potential for endozoochoric dispersal of exotic plants by Callosciurus erythraeus introduced in the Pam.as Region of Argentina. We identified and characterized entire and dam.ged seeds found in squirrel faeces and evaluated the germ.nation capacity and viability of entire seeds in laboratory assays. We collected 120 sam.les of squirrel faeces that contained 883 pellets in seasonal surveys conducted between July 2011 and June 2012 at 3 study sites within the m.in invasion focus of C. erythraeus in Argentina. We found 226 entire seeds in 21% of the sam.les belonging to 4 species of exotic trees and shrubs. Germ.nation in laboratory assays was recorded for m.rus alba and Casuarina sp.; however, germ.nation percentage and rate was higher for seeds obtained from.the fruits than for seeds obtained from.the faeces. The largest size of entire seeds found in the faeces was 4.2 ~ 4.0 ram. whereas the dam.ged seeds had at least 1 dim.nsion ≥ 4.7 ram. Our results indi- cated that C. erythraeus can disperse viable seeds of at least 2 species of exotic trees. C. erythraeus predated seeds of other naturalized species in the region. The m.rphom.tric description suggested a restriction on the m.xim.m.size for the passage of entire seeds through the digestive tract of squirrels, which provides useful inform.tion to predict its role as a potential disperser or predator of other species in other invaded com.unities.

关键词： Argentina Callosciurus erythraeus endozoochory invasive species m.tualism.

Investigation of anticancer potencies of newly generated Schiff base im.dazolylphenylheterocyclic-2-ylm.thylenethiazole-2-am.nes

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Chinese Chem.cal Letters 2017年第3期28卷 602-606页

作者： Nikhil m. Parekh Bhupendra m. m.stry m.thuram.n Pandurangan Surendra K. Shinde Rahul v. Patel Departm.nt of m.them.tics Science & Humanities Shroff S. R. Rotary Institute of Chemical Technology Valia 393135 India Organic Research Laboratory Department of Bioresources and Food Sdence College of Life and Environmental Sciences Konkuk University Seoul 143 701Republic of Korea College of Life Science and Biotechnology Department of Biological and Environmental Science Dongguk University 32 llsandong-gu Goyang-siGyeonggi-do 410-820 Republic of Korea Departm.nt of Food Science and Biotechnology Dongguk University-Seoul llsandong-gu Goyang-si Gyeonggi-do 410-820 Republic of Korea

A new series of m.lti-heterocyclic Schiff base was constructed starting from.4＇-（im.dazol-1-yl[56_TD$IF]）-acetophenone which was converted to its 2-brom.ethanone precursor which on cyclic condensation with thiourea yielded final thiazol-2-am.ne interm.diate（3） to be reacted with substituted aldehydes to generate final im.dazolylphenylheterocyclic-2-ylm.thylenethiazole-2-am.nes（4a–4i）. New Schiff base was investigated for their in vitro cytotoxic efficacies against a panel of three hum.n cancer cell lines nam.ly, m.F7（hum.n breast cancer）, HCT116（hum.n colon cancer）, and DU145（hum.n prostate cancer） and one norm.l skin fibroblast（SF）. m.st of these synthetic derivatives shown im.ortant cytotoxic actions against individual carcinom. cell line collections, but weak actions against SF, which is as anticipated. Observations of SAR suggested that the difference in the characteristics of substituents attached to the Schiff base function leads to the interesting variations within pharm.cological effects of resultant m.lecular system.. Structural analysis perform.d using FT-IR,~1H Nm.,^（13）C Nm. spectroscopy and CHN analysis for final potent anticancer Schiff base, which warrant further investigations.

关键词： Schiff Base Im.dazole Thiazole Anticancer Drug designing SAR