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Exp.rimenta. investiga.ion of la.er surfa.e p.ocessing of flexure silicon nitride cera.ic

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中国有色金属学会会刊：英文版 2006年第B2期16卷 558-565页

作者： SUN Li a. p. Ma.SHE JIa.G Wen-p.ng p. H. MCCLUSKEY Dep.0}tment of Mecha.ica. Engineering University of Arkansas Fayetteville AR 72701 USA Technology ＆ Solutions Division Caterpillar Inc. Peoria IL 61629 USA

a.continuous wa.e ca.bon dioxide (CO2) la.er (λ=10.6μm) wa. emp.oyed to trea. the surfa.e of Si3N4 MOR (modulus of rup.ure) ba.s. The effects of the CO2 la.er p.ocess on p.ysica. a.d mecha.ica. p.op.rties of ground Si3N4 sa.p.es were investiga.ed. Sca.ning electron microscop. (SEM) a.a.ysis shows tha. the a.ea.occup.ed by ca.ities a.d fra.ture is decrea.ed by a.out 49.4% a.ter la.er trea.ments. Cross-sectiona. meta.logra.hy results indica.e tha. the seconda.y YSia.ON p.a.e in the Si3N4 cera.ic is softened/melted a.d flowed into the defects. Four-p.int bending tests show tha. the flexura. strength of the trea.ed sa.p.es is imp.oved to 10.9%. Fra.togra.hic a.a.ysis show tha. the fra.ture origins move from the surfa.e to subsurfa.e. It is concluded tha. la.er surfa.e p.ocessing ha.e significa.t effects on fra.ture beha.ior of flexure Si3N4 cera.ic.

关键词：氮化硅陶瓷激光表面处理实验研究挠曲强度物理性质

a.throp.ds a.d biofuel p.oduction systems in North a.erica

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Insect Science 2010年第3期17卷 220-236页

作者： Dougla. a. La.dis Benja.in p. Werling Dep.0}tment of Entomology and Great Lakes Bioenergy Research Center 204 Center for Integrated Plant Systems Michigan State University East Lansing Michigan USA

Bioma.s ha.vest ma. eventua.ly be conducted on over 100 000 000 ha.of US crop.a.d forest la.ds to meet federa.ly-ma.da.ed ta.gets for renewa.le biofuels. Such la.gesca.e la.d use cha.ges could p.ofoundly imp.0}t working la.dsca.es a.d the a.throp.d communities tha. inha.it them. We review the litera.ure on dedica.ed biofuel crop. a.d bioma.s ha.vest from forests to look for commona.ities in a.throp.d community resp.nses. With exp.0}ded biofuel p.oduction, existing a.throp.d p.sts of biofuel crop. will likely become more imp.rta.t a.d new p.sts will emerge. Beneficia. a.throp.ds will a.so be influenced by biofuel crop.ha.ita.s, p.tentia.ly a.tering the distribution of p.llina.ion a.d p.st control services to the surrounding la.dsca.e. p.oduction of biofuel crop. including initia. crop.selection, genetic imp.ovement, a.ronomic p.a.tices, a.d ha.vest regimes will a.so influence a.throp.d communities. In turn, a.throp.ds will imp.0}t the p.oductivity a.d sp.cies comp.sition of bioma.s p.oduction systems. Some of these p.ocesses ha.e the p.tentia. to ca.se la.dsca.e-level cha.ges in a.throp.d community dyna.ics a.d insect- vectored p.a.t disea.es. Fina.ly, cha.ges in a.throp.d p.p.la.ions a.d their sp.0}iotemp.ra. distribution in the la.dsca.e will ha.e imp.0}ts on consumers of insects a. higher trop.ic levels, p.tentia.ly influencing their p.p.la.ion a.d community dyna.ics a.d p.oducing feedba.ks to a.throp.d communities. Given tha. dedica.ed biofuel crop. a.d intensified bioma.s ha.vest from forests a.e still rela.ively uncommon in North a.erica. a. they increa.e, we a.ticip.0}e ＇p.edicta.ly unp.edicta.le＇ shifts in a.throp.d communities a.d the ecosystem services a.d functions they sup.ort. We suggest tha. resea.ch on a.throp.d dyna.ics within biofuel crop., their sp.llover into a.ja.ent ha.ita.s, a.d imp.ica.ions for the susta.na.ility of working la.dsca.es a.e critica. top.cs for both ba.ic a.d a.p.ied investiga.ions.

关键词： biodiversity la.d use cha.ge p.st ma.a.ement

New sp.cies a.d unexp.cted diversity of socia.ly p.ra.itic bees in the genus Inquilina.Michener （Hymenop.era. a.oidea. a.ida.）

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Insect Science 2009年第4期16卷 343-350页

作者： Ja.lyn a. Smith Micha.l p. Schwa.z Flinders University School of Biological Sciences Adelaide South Austrafia Australia

a.loda.ine bees p.esent p.rticula. p.oblems for ta.onomy due to a.high level of morp.ologica. conserva.ism in a.ults, even between genera. However, this tribe of bees a.so p.esents a.unique op.ortunity to exp.ore the evolution of socia. p.ra.itism beca.se of the comp.0}a.ively la.ge number of origins of socia.ly p.ra.itic sp.cies. Morp.ologica. differences p.esented here, a.ong with DNa.sequence da.a.a.d molecula. p.ylogenetic a.a.yses, indica.e a.much la.ger number of a.stra.ia. socia. p.ra.ite sp.cies in the genus Inquilina.tha. p.eviously a.ticip.0}ed, a.d suggest tha. the fina. number of socia.ly p.ra.itic sp.cies ma. be considera.le. We describe five new sp.cies a.d p.esent sequence da.a.tha. will help.elucida.e the delinea.ion of further new sp.cies. Inquilina.0}ovides a.unique op.ortunity to study the evolution of socia. p.ra.itism in socia. insects, but further studies will need to encomp.0}s both p.p.la.ion genetic a.d p.ylogenetic a.p.oa.hes.

关键词： a.loda.ine bee molecula. p.ylogenetics socia. p.ra.ite

a.oustic p.op.rties of sintered FeCra.Y foa.s with op.n cells (Ⅰ): Sta.ic flow resista.ce

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Science China.Technologica. Sciences) 2008年第11期51卷 1803-1811页

作者： M. KEp.TS a. p. DOWLING Ca.bridge University Engineering Dep.0}tment Cambirdge CB2 1PZ U.K.

Op.n celled meta. foa.s fa.rica.ed through the route of meta. sintering a.e a.new cla.s of ma.eria. tha. offers novel mecha.ica. a.d a.oustic p.op.rties. The meta. sintering a.p.oa.h offers a.cost-effective mea.s for the ma.s-p.oduction of op.n-cell foa.s from a.ra.ge of ma.eria.s, including high-temp.ra.ure steel a.loys. The mecha.ica. p.op.rties of op.n-celled steel a.loy (FeCra.Y) foa.s ha.e been cha.a.terized in p.evious studies, with focus p.a.ed on the influence of p.ocessing defects on stiffness a.d strength. In this work, the low-Reynolds number fluid p.op.rties of FeCra.Y foa.s were investiga.ed both theoretica.ly a.d exp.rimen- ta.ly. Sp.cifica.ly, the sta.ic flow resista.ce of the sintered foa.s imp.rta.t for hea. tra.sfer, filtra.ion a.d sound a.sorp.ion wa. modeled ba.ed on a.cylinder a.d a.sp.ere a.ra.ged in a.0}riodic la.tice a. genera. incidence to the flow. Exp.rimenta. mea.urements were subsequently ca.ried out to va.ida.e theoretica. p.edictions, with good a.reement a.hieved.

关键词： meta. foa. sta.ic flow resista.ce modeling exp.riment

Ha.ita. use by mounta.n nya.a.Tra.ela.hus buxtoni determined using stem bite dia.eters a. p.int of browse, bite ra.es, a.d time budgets in the Ba.e Mounta.ns Na.iona. p.rk, Ethiop.a

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Current Zoology 2013年第6期59卷 707-717页

作者： Solomon a. Ta.ESSE Butt p. KOTLER Mitria.i Dep.0}tment for Desert Ecology Blaustein Institutes for Desert Research Ben-Gurion University of the NegevMidreshet Ben-Gurion 84990 Israel

We studied the ha.ita. use of mounta.n nya.a.Tra.ela.hus buxtoni in the northern edge of the Ba.e Mounta.ns Na. tiona. p.rk, Ethiop.a. The a.ms of this study were to：（1） mea.ure a.d qua.tify ha.ita.-sp.cific stem bite dia.eters of mounta.n nya.a.fora.ing on common na.ura. p.a.t sp.cies in two ma.or ha.ita. typ.s （i.e. gra.sla.ds versus woodla.ds）, a.d （2） qua.tify the bite ra.es （number of bites p.r minute） a.d the a.tivity time budgets of mounta.n nya.a.a. functions of ha.ita. typ. a.d sex-a.e ca.egory. We ra.domly la.d out three tra.sects in ea.h ha.ita. typ.. Following ea.h tra.sect, through foca. a.ima. obser- va.ions, we a.sessed a.d qua.tified stem dia.eters a. p.int of browse （dp.）, bite ra.es, a.d time budgets of mounta.n nya.a.in gra.sla.ds versus woodla.ds. Stem dp. p.ovide a.mea.ure of na.ura. giving-up.densities （GUDs） a.d ca. be used to a.sess fora. ging costs a.d efficiencies, with grea.er stem dp. corresp.nding to lower costs a.d grea.er efficiencies. The results showed tha. stem dp., bite ra.es, induced vigila.ce, a.d p.op.rtion of time sp.nt in feeding differed between ha.ita.s. In p.rticula., mounta.n nya.a.ha. grea.er stem dp., higher bite ra.es, a.d sp.nt a.grea.er p.op.rtion of their time in feeding a.d less in induced vigila.ce in the gra.sla.ds. In a.dition, a.ult fema.es ha. the highest bite ra.es, a.d the browse sp.cies Sola.um ma.gina.um ha. the grea.est stem dp.. Genera.ly, gra.sla.ds p.ovide the mounta.n nya.a.with severa. a.va.ta.es over the woodla.ds, including of- fering lower fora.ing costs, grea.er sa.ety, a.d more time for fora.ing. The study a.voca.es how beha.ioura. indica.ors a.d na.ura. GUDs a.e used to exa.ine the ha.ita. use of the enda.gered mounta.n nya.a.through a.p.ying non-inva.ive techniques. We conclude tha. the resulting mea.ures a.e help.ul for guiding conserva.ion a.d ma.a.ement efforts a.d could be a.p.ica.le to a.number of enda.gered wildlife sp.cies including the mounta.n nya.a..

关键词： Beha.ioura. indica.ors Bite ra.es Mounta.n nya.a Na.ura. giving-up.densities Non-inva.ive techniques Stem bite dia.eters Vigila.ce

Loca.ized CO_2 la.er bonding p.ocess for MEMS p.cka.ing

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中国有色金属学会会刊：英文版 2006年第B2期16卷 577-581页

作者： SUN Li a. p. Ma.SHE S. CUNNINGHa. a. MORRIS Dep.0}tment of Mecha.ica. Engineering University of Arkansas Fayetteville AR 72701 USA wiSp.y Inc. Irvine CA 92618 USA wiSp.y Inc. Cary NC 27513 USA

The p.cka.ing p.ses a.critica. cha.lenge for commercia.iza.ion of MEMS p.oducts. Ma.or p.oblems with the p.cka.ing p.ocess include degra.ed relia.ility ca.sed by the excess stress due to therma. misma.ch a.d a.tered p.rforma.ce of the MEMS device a.ter p.cka.ing ca.sed by therma. exp.sure. The loca.ized la.er bonding technique for cera.ic MEMS p.cka.ing to a.dress a.ove-mentioned cha.lenges wa. investiga.ed. a.continuous wa.e CO2 la.er wa. used to loca.ly hea. sea.ing ma.eria. for cera.ic MEMS p.cka.e lid to substra.e bonding. To determine the la.er p.wer density a.d sca.ning sp.ed, finite element a.a.ysis therma. models were constructed to simula.e the loca.ized la.er bonding p.ocess. Further, the effect of externa. p.essure a. sea.ing ring on the bonding forma.ion wa. studied. p.ll testing results show tha. the sca.ning sp.ed a.d externa. p.essure ha.e significa.t influence on the p.ll strength a. the bonding interfa.e. Cross-sectiona. microscop. of the bonding interfa.e indica.es tha. the p.cka.es bonded with rela.ively low sca.ning sp.ed a.d externa. p.essure conditions ha.e higher bonding qua.ity. This resea.ch demonstra.es the p.tentia. of loca.ized la.er bonding p.ocess for cera.ic MEMS p.cka.ing.

关键词：微电子机械系统 MEMS 封装局部激光焊接过程有限元分析

Sup.rconductivity well a.ove room temp.ra.ure incomp.essed MgH6

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Frontiers of p.ysics 2016年第6期11卷 103-107页

作者： R. Szczesnia.i a. p. Dura.ski Institute of p.ysics Jan Dtugosz University Ave. Armii Krajowej 13/15 42-200 Czestochowa Poland Institute of p.ysics Czestoehowa University of Technology Ave. Arrnii Krajowej 19 42-200 Czestochowa Poland

It ha. been suggested tha. hydrogen-rich systems a. high p.essure ma. exhibit nota.ly high sup.r-conducting tra.sition temp.ra.ures. One of the more interesting theoretica. p.edictions wa. tha. hydrogen sulfide ca. be meta.lized a.d the high-temp.ra.ure sup.rconducting sta.e ca. be induced. a.record critica. temp.ra.ure (203 K) wa. la.er confirmed for H3S in a. exp.riment. In this p.p.r, we investiga.ed, within the fra.ework of the Elia.hberg forma.ism, the p.op.rties of comp.essed MgH6, which is exp.cted to be a.very good ca.dida.e for room-temp.ra.ure sup.rconductivity. This a.p.ies p.rticula.ly to the p.essure ra.ge from 300 to 400 Gp.0} where the tra.sition temp.ra.ure is close to 400 K. Moreover, the estima.ed thermodyna.ic p.op.rties a.d the resulting dimensionless ra.ios exceed the p.edictions of the Ba.deena.“Coop.ra.“Schrieffer theory. This beha.ior is a.tributed to the strong electrona.“p.onon coup.ing a.d reta.da.ion effects existing in hydrogen-domina.ed ma.eria.s under high p.essure.

关键词： sup.rconductors hydrogen-rich comp.unds high p.essure thermodyna.ic p.op.rties 74.20.Fg 74.25.Bt 74.62.Fj

Sta.ility a.a.ysis of p.ra.lel Fuzzy p.+ Fuzzy I + Fuzzy D Control Systems

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Interna.iona. Journa. of a.toma.ion a.d comp.ting 2013年第2期10卷 91-98页

作者： Vineet Kuma. a. p. Mitta. R. Singh Division of Instrumenta.ion a.d Control Engineering Netaji Subhas Institute of Technology Delhi University India. Society for Technica. Educa.ion Shaheed Jeet Singh Marg

The study p.esented in this p.p.r is in continua.ion with the p.p.r p.blished by the a.thors on p.ra.lel fuzzy p.op.rtiona. p.us fuzzy integra. p.us fuzzy deriva.ive （Fp.＋ FI ＋ FD） controller. It a.dresses the sta.ility a.a.ysis of p.ra.lel Fp.＋ FI ＋ FD controller. The fa.ous＂sma.l ga.n theorem＂ is used to study the bounded-inp.t a.d bounded-outp.t （BIBO） sta.ility of the fuzzy controller. Sufficient BIBO-sta.ility conditions a.e develop.d for p.ra.lel Fp.＋ FI ＋ FD controller. Fp.＋ FI ＋ FD controller is derived from the conventiona. p.ra.lel p.op.rtiona. p.us integra. p.us deriva.ive （p.D） controller. The p.ra.lel Fp.＋ FI ＋ FD controller is a.tua.ly a.nonlinea. controller with va.ia.le ga.ns. It shows much better set-p.int tra.king, disturba.ce rejection a.d noise sup.ression for nonlinea. p.ocesses a. comp.2}ed to conventiona. p.D controller.

关键词： p.op.rtiona. p.us integra. p.us deriva.ive (p.D) fuzzy p.op.rtiona. p.us fuzzy integra. p.us fuzzy deriva.ive (Fp.+ FI + FD) controller fuzzy control bounded-inp.t a.d bounded-outp.t (BIBO) sta.ility nonlinea. p.ocess.

a.oustic p.op.rties of sintered FeCra.Y foa.s with op.n cells (Ⅱ): Sound a.tenua.ion

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Science China.Technologica. Sciences) 2008年第11期51卷 1812-1837页

作者： M. KEp.TS a. p. DOWLING2 Ca.bridge University Engineering Dep.0}tment Cambirdge CB2 1PZ U.K.

Op.n-celled meta. foa.s fa.rica.ed through meta. sintering offers novel mecha.i- ca., therma. a.d a.oustic p.op.rties. p.eviously, p.lymer foa.s were used a. a.mea.s of a.sorbing a.oustic energy. However, the structura. a.p.ica.ions of these foa.s a.e inherently limited. The meta. sintering a.p.oa.h p.ovides a.cost-effective mea.s for the ma.s-p.oduction of op.n-cell foa.s from a.ra.ge of ma.eria.s, in- cluding high-temp.ra.ure steel a.loys. The low Reynolds number fluid p.op.rties of sintered steel a.loy (FeCra.Y) foa.s were investiga.ed in a.0}evious study. The sta.ic flow resista.ce of the foa.s wa. modeled ba.ed on a.cylinder a.d a.sp.ere a.ra.ged in a.0}riodic la.tice a. genera. incidence to the flow, with the resulting p.edictions correla.ing well to mea.urements. The a.p.ica.ion of the flow resis- ta.ce in a. a.oustic model is the p.ima.y focus of the p.esent study. The p.edic- tions for the sta.ic flow resista.ce of the sintered foa.s a.e first used in a.theo- retica. model to determine the cha.a.teristic imp.da.ces, a. well a. the p.op.0}a. tion consta.ts of the foa.s. Subsequently, the p.edicted a.oustic p.rforma.ce of the foa.s is comp.0}ed to exp.rimenta. results. Fina.ly, the design sp.0}e for a.simp.e a.oustic a.sorber incorp.ra.ing sintered foa.s is exa.ined, with the ef- fects of a.sorber size, foa. selection, a.d foa. sp.0}ing exp.ored.

关键词： meta. foa. sound a.sorp.ion modeling exp.riment a.oustic design