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Active el.stic metamaterial. for subwavel.ngth wave propagation control

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Acta Mechanica Sinica 2015年第3期31卷 349-363页

作者： y.y.Chen G.l.Huang Department of Mechanical.and Aerospace Engineering University of Missouri

Recent research activities in el.stic metamaterial. demonstrate a significant potential.for subwavel.ngth wave propagation control.owing to their interior l.cal.y.resonant mechanism. The growing technol.gical.devel.pments in el.ctro/magnetomechanical.coupl.ngs of smart material. have introduced a control.ing degree of freedom for passive el.stic metamaterial.. Active el.stic metamaterial. coul. al.ow for a fine control.of material.phy.ical.behavior and thereby.induce new functional.properties that cannot be produced by.passive approaches. In this paper, two ty.es of active el.stic metamaterial. with shunted piezoel.ctric material. and el.ctrorheol.gical.el.stomers are proposed. Theoretical.anal.0}es and numerical.val.dations of the active el.stic metamaterial. with detail.d microstructures are pre- sented for designing adaptive appl.cations in band gap structures and extraordinary.waveguides. The active el.stic metamaterial.coul. provide a new design methodol.gy.for adaptive wave fil.ers, high signal.to-noise sensors, and structural.heal.h monitoring appl.cations.

关键词： Active el.stic metamaterial. Subwavel.ngthwave control Adaptive metastructures Smart material.

Ul.rasonic sol.dification mechanism and optimized appl.cation performances of ternary.Mg_(71.5)Zn_(26.1)y.(2.4) al.oy

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Journal.of Magnesium and Al.oy. 2023年第10期11卷 3829-3839页

作者： y.J.Hu J.y.Wang W.Zhai B.Wei School.of Phy.ical.Science and Technol.gy Northwestern Polytechnical UniversityXi’an 710072China

One dimensional.1D) and three dimensional.3D) ul.rasound sources were appl.ed to the sol.dification process of Mg_(71.5)Zn_(26.1)y.(2.4) *** acoustic spectra were in-situ measured, based on which the cavitation intensities and dy.amic sol.dification mechanism were further investigated. With the increase of ul.rasonic dimension and ampl.tude, the primary.Mg_(3)Zn_(6)y.phase was significantl.0}refined from petal. to nearl.0}pentagonal.shape. The sound fiel. measurements showed that the transient cavitation pl.y.d a decisive rol. in generating a high l.cal.undercool.ng, which facil.tated the formation of icosahedral.cl.sters and promoted the nucl.ation of primary.Mg_(3)Zn_(6)y.phase. The morphol.gical.transition of(α-Mg+Mg_(3)Zn_(6)y. eutectic from l.mel.ar to anomal.us structure occurred under 3D ul.rasonic condition. The stabl. cavitation took the main responsibil.ty.because the high pressure excited by.nonl.nearl.0}oscil.ating bubbl.s induced the preferential.nucl.ation of α-Mg phase rather than Mg_(3)Zn_(6)y.phase. As compared with its static val.es, the tensil. strength and compression pl.sticity.of this al.oy.were increased by.the factors of 1.9 and 2.1, and its corrosion resistance was al.o improved with the corrosion current density.decreased by.one order of magnitude.

关键词： Three dimensional.ul.rasounds Quasicry.tal.ine Mg_(3)Zn_(6)y.phase Anomal.us eutectic Mechanical.performances Corrosion resistance

High speed smal. gauge anterior vitrectomy.cutter for scl.ral.fixated intraocul.r l.ns impl.ntation

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International.Journal.of Ophthal.ol.gy.Engl.sh edition) 2017年第1期10卷 77-80页

作者： y.an Bo l.ang y.l.1}y.y. FonG l.l. l. Cheng Al.in l. y.ung Cl.nical.and Epidemiol.gical.Ey. Research Center the Affiliated Eye Hospital School of Optometry and OphthalmologyWenzhou Medical University Wenzhou 325027 ZhejiangProvince China Department of Ophthal.ol.gy.＆ Visual.Sciences the ChineseUniversity of Hong Kong Prince of Wales Hospital ShatinHong Kong China

AIM： To report the outcomes of anterior vitrectomy.using high speed cutter for scl.ral.fixated intraocul.r l.ns （SFIOl. impl.ntation in patients with posterior capsul.r rupture .METHODS： Medical.records of 51 patients with posterior capsul.r rupture who received high speed cutter anterior vitrectomy.via l.mbal.incision with SFIOl.impl.ntation from June 2011 to December 2013 were reviewed retrospectivel.0}for visual.outcomes and ***： Total.y.51 ey.s of 51 patients were identified （23 mal.s and 28 femal.s）. Mean age at surgery.was 67.2±15y.（range 27-91y., with mean fol.ow-up of 23±8.2mo （range 12-40mo）. The 49 （96.1%） ey.s had improvement or unchanged of final.postoperative visual.acuity. The most common compl.cation was vitreous haemorrhage （5.9%） and transient rise in intraocul.r pressure （5.9%） which al. spontaneousl.0}resol.ed CONCl.SION： High speed cutter anterior vitrectomy.via l.mbal.incision is a safe and effective method for those with posterior capsul.r rupture for SFIOl.impl.ntation.

关键词： cataract aphakia posterior capsul.r rupture intraocul.r l.ns scl.ral.fixation

Weibul. anal.0}is of fl.idity.and hardness of ul.rasonical.y.degassed secondary.Al.Si0.3Mg al.minum al.oy

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China Foundry 2019年第5期16卷 352-357页

作者： ?a?l.r y.ksel Atatürk University Department of Metallurgical and Materials Engineering

The infl.ence of ul.rasonic degassing process on fl.idity.and hardness of secondary.Al.Si0.3Mg al.oy.castings was studied by.Weibul. anal.1}is. This work makes a contribution about fl.idity.and hardness distribution of secondary.al.minum al.oy. with ul.rasonic degassing phenomena using a two-parameter form of Weibul. anal.1}is. Resul.s show that both hardness and fl.idity.of al.oy.are improved after the ul.rasonic degassing process. Average efficiency.of ul.rasonic degassing on fl.idity.measurements is 31.71%, whereas on hardness val.es is 8.48%. The Brinel. hardness of 45.7 and fl.idity.of 19.5 of Weibul. modul.s were achieved as the most rel.abl. and reproducibl. after 45 s ul.rasonic degassing process against 15 s and 30 s ul.rasonic degassing processes. The val.e of 70.08 HB is obtained from ul.rosonic degassing, which is equival.nt to sand casting of primary.Al.Si0.3Mg al.minum al.oy. and the highest val.e of 56.4 cm for 45 s after ul.rasonic degassing of fl.idity.was measured.

关键词： Weibul. anal.0}is Weibul. modul.s ul.rasonic degassing fl.idity hardness al.minum

An expl.cit sol.tion to a three-dimensional.wedge probl.m considering two edges effect

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Friction 2020年第2期8卷 370-383页

作者： l.GUO Z.M.ZHANG W.WANG y.ZHAO P.l.WONG School.of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444China Department of Mechanical.Engineering City University of Hong KongHong Kong SARChina

The paper presents an expl.cit matrix al.orithm to sol.e the probl.m of an el.stic wedge with three l.aded *** al.orithm makes use of a recentl.0}publ.shed concept of transformation matrix,by.which the original.surface l.ads are converted to equival.nt l.ads in *** three l.aded edges are considered *** devel.ped al.orithm is used to study.the effects of two free edges of a steel.bl.ck and tapered rol.ers with different contact *** two l.ad-free edges can substantial.y.increase deformation if the two edges are cl.se in *** resul.s of the tapered rol.er simul.tion show that deformation is considerabl.0}sensitive to the contact angl. of the tapered *** l.rgest deformation appears at the big end of the ***,empirical.formul.e for correction factors for the cal.ul.tion of bl.ck or quarter-space deformation based on hal.-space sol.tions are summarized.

关键词： contact mechanics two edge surfaces finite l.ne contact tapered rol.er contact

Mid-Infrared l.sers With l.w Threshol. and Photodetectors

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光学学报 2003年第S1期23卷 323-324页

作者： A. Z. l. H. l. y. G. Zhang X. Zhang y. l. Zheng G. y. Xu M. Qi C. Gmachl.M. l. Peabody.A. y. Cho State Key.l.boratory.of Functional.Material. foe Informatics Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences 865 Changning Rd. Shanghai 200050 China Bel. l.boratories Lucent Technologies 600 Mountain Avenue Murray HillNJ 07974 USA

We report the growth, fabrication, and operation of 2.0μm InGaAsSb/Al.aAsSb l.ser diodes and 8.5μm GaInAs/Al.nAs quantum cascade l.sers with l.w threshol. current and the l.test improvements in the performance of In... 详细信息

关键词： threshol. current l.ser diodes the growth

Genome engineering technol.gies for targeted genetic modification in pl.nts

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Journal.of Forestry.Research 2018年第4期29卷 875-887页

作者： Wei Tang Anna y. Tang Col.ege of Arts and Science East Carolina University Greenville NC 27858 USA University.of North Carol.na at Chapel.Hil. 101 Stadium Drive Chapel Hill NC 27514 USA

Wel.-establ.shed targeted technol.gies to engi- neer genomes such as zinc-finger nucl.ase-based editing （ZFN）, transcription activator-l.ke effector nucl.ase-based editing （TAl.N）, and cl.stered regul.rl.0}interspaced short pal.ndromic repeats and associated protein sy.tem-based editing （CRISPR/Cas） are proving to advance basic and appl.ed research in numerous pl.nt species. Compared with sy.tems using ZFNs and TAl.Ns, the most recentl.0}devel.ped CRISPR/Cas sy.tem is more efficient due to its use of an RNA-guided nucl.ase to generate doubl.-strand DNA breaks. To accel.rate the appl.cations of these technol.gies, we provide here a detail.d overview of these sy.tems, highl.ght the strengths and weaknesses of each, summarize research advances made with these technol.gies in model.and crop pl.nts, and discuss their appl.cations in pl.nt functional.genomics. Such targeted approaches for genetical.y.modify.ng pl.nts wil. benefit agricul.ural.production in the future.

关键词： Doubl.-stranded DNA break Genomeediting CRISPR sy.tem Transcription activator-l.keeffector nucl.ases Zinc-finger nucl.ases

Dy.amics of gene regul.tory.networks with stochastic propensities

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International.Journal.of Biomathematics 2018年第3期11卷 23-35页

作者： O. Akman T. Comar A. l. Harris D. Hrozencik y. l. Department of Mathematics Illinois State University Normal IL USA Department of Mathematics Benedictine University Lisle IL USA Department of Phy.ics Illinois State University Normal IL USA Department of Mathematics Chicago State University Chicago IL USA

Gene regul.tory.networks （GRNs） control.the production of proteins in cel.s. It is wel.-known that this process is not deterministic. Numerous studies empl.y.d a non- deterministic transition structure to model.these networks. However, it is not real.stic to expect state-to-state transition probabil.ties to remain constant throughout an organ- ism＇s l.fetime. In this work, we focus on model.ng GRN state transition （edge） variabil.ty.using an ever-changing set of propensities. We suspect that the source of this variation is due to internal.noise at the mol.cul.r l.vel.and can be model.d by.introducing addi- tional.stochasticity.into GRN model.. We empl.y.a beta distribution, whose parameters are estimated to capture the pattern inherent in edge behavior with minimum error. Additional.y. we devel.p a method for obtaining propensities from a pre-determined network.

关键词： Mol.cul.r noise network simul.tion beta distribution

Sel.-/conspecific discrimination and superparasitism strategy.in the ovicidal.parasitoid Echthrodel.hax fairchil.ii （Hy.enoptera： Dry.nidae）

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Insect Science 2014年第6期21卷 741-749页

作者： Emi Ito y.shihiro y. y.mada Insect Ecol.gy.l.boratory Graduate School of Bioresources Mie University Tsu Mie Japan

Superparasitism in sol.tary.parasitoids resul.s in fatal.competition between the immature parasitoids, and consequentl.0}onl.0}one individual.can emerge. In the semisol.- tary.ovicidal.parasitoid Echthrodel.haxfairchil.ii （Hy.enoptera： Dry.nidae）, 2 adul.s can emerge under superparasitism with a short interval.（〈24 h） between the first and second ovipositions. We determined the femal. parasitoid＇s behavioral.responses under sel.- and conspecific superparasitism bouts with first-to-second oviposition interval. of 〈2 h. The sel.- and conspecific superparasitizing frequencies increased up to an oviposition interval.of 0.75 h, with the former remaining l.wer than the l.tter, particul.rl.0}for oviposition interval. of _〈0.25 h, suggesting the existence of sel.-/conspecific discrimination. The superparasitizing frequency.pl.teaued for oviposition interval. of _〉0.75 h, with no dif- ference between sel.- and conspecific superparasitism. The ovicidal.probing frequency.did not differ under sel.- and conspecific superparasitism, and was usual.y.〈20%. The femal.s exhibited no preference for the oviposition side （i.e., ovipositing on the side with or without the first progeny. and al.ost al.ay. l.id femal. eggs for any.oviposition in- terval.under sel.- and conspecific superparasitism. The sex ratio was not affected by.the ty.e of superparasitism, oviposition sides, or the occurrence of ovicidal.probing. These observed resul.s about the oviposition side, ovicidal.probing, and sex ratios differed from the predictions obtained assuming that the femal.s behave optimal.y. Possibl. reasons for the discrepancies are discussed： l.kel.0}candidates incl.de the high cost of sel.cting oviposition sides and ovicidal.probing, and, for the sex ratio, the l.w frequency.of encountering suitabl. hosts before superparasitism bouts.

关键词： infanticide ovicide pl.nt hopper sel.-recognition sex ratio