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基于分子束外延技术可控制备Bi原子团簇的研究

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原子与分子物理学报 2025年第2期42卷 79-84页

作者：马玉麟郭祥丁召贵州大学大数据与信息工程学院贵阳550025 贵州省微纳电子与软件技术重点实验室贵阳550025 半导体功率器件可靠性教育部工程研究中心贵阳550025

本研究基于分子束外延(MBE)技术在s.(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇... 详细信息

本研究基于分子束外延(MBE)技术在s.(111)衬底表面成功制备金属Bi原子团簇.首先,分别在100℃、125℃、150℃、175℃、200℃的生长温度下,制备了大小均一、密度不同的Bi原子团簇.实验结果表明,可以通过改变生长温度来精细控制Bi原子团簇的密度,当温度升高100℃,密度从1.05×10^(11)cm^(-2)降低至2.5×10^(7)cm^(-2),实现对团簇密度4个数量级的可控调节,并且发现Bi原子团簇密度对生长温度的依赖性符合经典成核理论.其次,分别在10 s.15 s.20 s.沉积时长下,制备了密度相同、尺寸各异的Bi原子团簇.实验结果表明,可以通过改变沉积时长来精细控制Bi原子团簇的尺寸:当沉积时长增加10 s.高度和直径分别从8.5 nm和65 nm增大到13.7 nm和100 nm,实现对团簇尺寸在10 nm高度、80 nm直径范围的可控调节,并且发现Bi原子团簇尺寸对沉积时长的依赖性符合晶体生长动力学.与分子束外延制备传统的Ⅲ族(Al,Ga,In)原子团簇做对比,这些结果可以为制备Ⅴ族原子团簇提供实验参考和指导,从而促进纳米级含Bi材料的制备.

关键词：分子束外延 Bi原子团簇生长温度沉积时长经典成核理论晶体生长动力学

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The Method of Fundamental s.lutions.for s.lving Exterior Axis.mmetric Helmholtz Problems.w.th High w.ve-Number

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Advances.in Applied Mathematics.and Mechanics 2013年第4期5卷 477-493页

作者： w.n Chen Ji lin C.s.Chen College of Engineering Mechanics Hohai UniversityNanjing 210098JiangsuChina Department of Mathematics University of Southern MississippiHattiesburgMS 39406USA

In this.paper,w. inves.igate the method of fundamental s.lutions.MFs.for s.lving exterior Helmholtz problems.w.th high w.ve-number in axis.mmetric *** the coefficientmatrix in the linear s.s.em res.lting fromtheMFs.approximation has.a block circulant s.ructure,it can be s.lved by the matrix decompos.tion algorithm and fas. Fourier trans.orm for the fas. computation of large-s.ale problems.and meanw.ile s.ving computer memory *** numerical examples.are provided to demons.rate its.applicability and efficacy in tw. and three dimens.onal domains.

关键词： Method of fundamental s.lutions exterior Helmholtz problem circulant matrix fas. Fourier trans.orm axis.mmetric domain

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近代西方人调查记中的彝族服饰文化研究

丝绸 2025年第1期62卷 118-126页

作者：林儒凡王雨萍夏帆浙江理工大学服装学院杭州311103

目前关于西南彝族服饰的研究各地区进展差异明显,缺乏系统性。本研究旨在通过梳理近代西方调查者对中国西南彝族的记录,将近代的彝族服饰按照地域分为三大区域:大小凉山区域、云南红河流域,云南三江流域及金沙江流域。结合国内的本土文... 详细信息

目前关于西南彝族服饰的研究各地区进展差异明显,缺乏系统性。本研究旨在通过梳理近代西方调查者对中国西南彝族的记录,将近代的彝族服饰按照地域分为三大区域:大小凉山区域、云南红河流域,云南三江流域及金沙江流域。结合国内的本土文献和田野调查资料,深入考析彝族服饰在不同地区的特点及其异变,并探讨这些差异背后所体现的经济、社会和文化因素。通过将西方与本土资料结合互证,研究认为近代时期,彝族服饰在三大地理区域呈现显著差异,体现了各区域经济、文化影响与社会融合程度的不同,其中大凉山地区保留较多传统元素,红河流域受汉文化与外来文化影响较深,三江及金沙江流域则展现出中间态。服饰多样性与时代变迁反映了彝族文化的演进和社会文化的互动。

关键词：近代西方人调查记彝族服饰四川凉山云南地区服饰演变

Formation of radially expanding liquid s.eet by impinging tw. round jets

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Applied Mathematics.and Mechanics.Englis. Edition) 2010年第8期31卷 937-946页

作者：王志亮 s.P．lin 周哲玮 s.anghai Ins.itute of Applied Mathematics.and Mechanics Shanghai University Shanghai 200072 P. R. China Department of Mechanical and Aeronautical Engineering Clarkson University Potsdam NY 13699 USA

A thin circular liquid s.eet can be formed by impinging tw. identical round jets.agains. each other. The liquid s.eet expands.to a certain critical radial dis.ance and breaks. The uns.eady proces. of the formation and breakup of the liquid s.eet in the ambient gas.is.s.mulated numerically. Both liquid and gas.are treated as.incompres.ible New.onian fluids. The flow.cons.dered is.axis.mmetric. The liquid-gas.interface is.modeled w.th a level s.t function. A finite difference s.heme is.us.d to s.lve the governing Navier-s.okes.equations.w.th phys.cal boundary conditions. The numerical res.lts.s.ow.how.a thin circular s.eet can be formed and break at its.circular edge in s.ow.motion. The s.eet continues.to thin as.it expands.radially. Hence, the w.ber number decreas.s.radially. The w.ber number is.defined as.ρu 2 h/σ, w.ere ρ and σ are, res.ectively, the liquid dens.ty and the s.rface tens.on, and u and h are, res.ectively, the average velocity and the half s.eet thicknes. at a local radial location in the liquid s.eet. The numerical res.lts.s.ow.that the s.eet indeed terminates.at a radial location, w.ere the w.ber number reaches.one as.obs.rved in experiments. The s.atio-temporal linear theory predicts.that the breakup is.initiated by the s.nuous.mode at the critical w.ber number w. c =1, below.w.ich the abs.lute ins.ability occurs. The other independent mode called the varicos. mode grow. more s.ow.y than the s.nuous.mode according to the linear theory. How.ver, our numerical res.lts.s.ow.that the varicos. mode actually overtakes.the s.nuous.mode during the nonlinear evolution, and is.res.ons.ble for the final breakup. The linear theory predicts.the nature of dis.urbance w.ves.correctly only at the ons.t of the ins.ability, but cannot predict the exact cons.quence of the ins.ability.

关键词： flow.ins.ability level s.t method interfacial flow liquid jet

Modeling of the Relations.ip Betw.en Pore s.ze Dis.ribution and Thicknes. of Ceramic MF Membrane

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Chines. Journal of Chemical Engineering 1998年第3期6卷 38-48页

作者：董军航王沛徐南平时钧 Jerry Y.s.lin Department of Chemical Engineering Univers.ty of Cincinnati Cincinnati Ohio OH 45221 Us.

The pore s.ze dis.ribution(Ps.)meas.red by the gas.bubble point(GBP)method ofceramic microfiltration(MF)membranes.prepared by s.s.ens.on technique w.s.found to be s.gnifi-cantly influenced by the membrane thicknes..A culm-like model for pore s.ructure w.s.introduced tocharacterize the membrane pores.ins.ead of the conventional model w.ich does.not reflect the radius.ariation along the pore pas.ages.and is.unable to explain the thicknes. effect on the membrane Ps..A laminate s.ructure,taking the culm-like model for pore s.ructure into cons.deration,w.s.hypoth-es.zed for ceramic MF membranes.A mathematical model w.s.then es.ablis.ed to quantitativelydes.ribe the relations.ip betw.en the membrane number Ps. and the membrane *** w.re obtained for the correlation of mean pore s.ze and s.mulation of the Ps. for ceramicMF membranes.

关键词： modeling pore s.ructure pore s.ze dis.ribution thicknes. ceramic membrane

A fas. forw.rd computational method for nuclear meas.rement us.ng volumetric detection cons.raints

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Nuclear s.ience and Techniques 2024年第2期35卷 47-63页

作者： Qiong Zhang lin-Lv lin Univers.ty of Electronic s.ience and Technology of China Chengdu 610000China

Ow.ng to the complex lithology of unconventional res.rvoirs.field interpreters.us.ally need to provide a bas.s.for interpretation us.ng logging s.mulation *** the various.detection tools.that us. nuclear s.urces.the detector res.ons. can reflect various.types.of information of the *** Monte Carlo method is.one of the primary methods.us.d to obtain nuclear detection res.ons.s.in complex ***,this.requires.a computational proces. w.th extens.ve random s.mpling,cons.mes.cons.derable res.urces.and does.not provide real-time res.ons. ***,a novel fas. forw.rd computational method(FFCM)for nuclear meas.rement that us.s.volumetric detection cons.raints.to rapidly calculate the detector res.ons. in various.complex environments.is.***,the data library required for the FFCM is.built by collecting the detection volume,detector counts.and flux s.ns.tivity functions.through a Monte Carlo ***,bas.d on perturbation theory and the Rytov approximation,a model for the detector res.ons. is.derived us.ng the flux s.ns.tivity function method and a one-group diffus.on *** environmental perturbation is.cons.rained to optimize the model according to the tool s.ructure and the impact of the formation and borehole w.thin the effective detection ***,the method is.applied to a neutron poros.ty tool for *** various.complex s.mulation environments.the maximum relative error betw.en the calculated poros.ty res.lts.of Monte Carlo and FFCM w.s.6.80%,w.th a rootmean-s.uare error of 0.62 *** field w.ll applications.the formation poros.ty model obtained us.ng FFCM w.s.in good agreement w.th the model obtained by interpreters.w.ich demons.rates.the validity and accuracy of the propos.d method.

关键词： Nuclear meas.rement Fas. forw.rd computation Volumetric cons.raints

Online traffic-aw.re linked VM placement in cloud data centers

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s.ience China(Information s.iences. 2020年第7期63卷 182-204页

作者： Liw.i lin David s.L.w.I Ruhui MA Jian LI Haibing GUAN s.anghai Key Laboratory of s.alable Computing and s.s.ems Shanghai Jiao Tong University Department of Computer & Information s.iences Fordham University

In cloud computing, virtual machine(VM) placement plays.a crucial role in data center(DC)management, as.different w.ys.of VM placement may require different s.s.em res.urces. As.Cis.o res.arch reveals.that virtualization of DC increas.s.traffic w.thin the DC and caus.s.netw.rk bandw.dth to become s.arce res.urce, recent res.arches.have been focus.ng on traffic-aw.re VM placement. How.ver, previous.traffic-aw.re VM placement s.hemes.treat the VM placement as.a s.atic proces. in that they do not take into account the impact of the current placement decis.on on the s.bs.quent placement. In this.paper,w. thus.propos. a novel online traffic-aw.re VM placement s.heme. Our s.heme view. VM placement as.a context-s.ns.tive dynamic proces. in that the decis.on of every s.ep of the placement is.made aiming at helping the s.bs.quent s.eps.of placement to reduce the required netw.rk bandw.dth in the long run. In our s.heme, w. cons.der not only inter-VM traffic but als. the bandw.dth cons.raint of a phys.cal machine(PM) w.en making a VM placement decis.on. To realize our objective, w. put thos. VMs.w.th clos. end time in the s.me or clos. proximity PMs.s. that w.en the VMs.are terminated, one can make enough room for the future arrivals.s. as.to not only minimize the number of active PMs.but als. reduce netw.rking cos.s. w. conduct extens.ve s.mulations.to verify the s.periority of our s.heme in terms.of netw.rking cos.s.and energy cons.mption. s.mulation res.lts.s.ow.that our s.heme outperforms.improved-bes.-fit-decreas.ng(IBFD) s.heme, a revis.d bes.-fit vers.on that takes.inter-VM traffic into account, by 30%–40% on netw.rk cos. under various.s.enarios. Our s.heme als. promis.s.10%–25% pow.r s.vings.compared w.th IBFD.

关键词： linked VMs traffic-aw.re online VM placement cloud data center energy efficient

s.UDY ON COMPOs.TION, MICROs.RUCTURE AND HARDNEs. OF DLC FILMs.BY VCAD

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Acta Metallurgica s.nica(Englis. Letters. 2003年第4期16卷 271-275页

作者： L.Chen Z.Y.Liu D.C.Zeng w.Q.Qiu Z.H.Yuan s.s.lin H.J.Hou Ins.ituteofMaterials.cience&Technology CollegeofMechanicalEngineeringSouthChinaUniversityofTechnologyGuangzhou510640China GuangzhouRes.archIns.ituteofNon-Ferrous.etals Guangzhou510651ChinaManuscriptreceived25November2002

DLC s.per-hard films.have been depos.ted on the s.bs.rates.of s.ngle crys.alline s., pure Ti and s.ainles. s.eel 18-8 by a method of vacuum cathode arc depos.tion (VCAD). The compos.tion, micros.ructure and micro-hardnes. of the films.have been s.udied in this.paper. The res.lts.indicate that hardnes. of the DLC films.is.different on the different s.bs.rates. Hardnes. of the films.increas.s.w.th decreas.ng in s.rface roughnes. of the films. The maximum value of micro-hardnes. belongs.to the DLC films.depos.ted under the hydrogen pres.ure of 0.35Pa and the negative bias.of 100V.

关键词： DLC films vacuum cathode arc depos.tion micro-hardnes.

Pos.tive-Controllability,Pos.tive-Near-Controllability,and Canonical Forms.of Driftles. Dis.rete-Time Bilinear s.s.ems

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Journal of s.s.ems.s.ience & Complexity 2022年第4期35卷 1225-1243页

作者： TIE lin s.hool of Automation s.ience and Electrical Engineering Beihang UniversityBeijing100083China

Controllable canonical forms.play important roles.in the analys.s.and des.gn of control *** this.paper,a fundamental clas. of dis.rete-time bilinear s.s.ems.are *** s.s.ems.are of interes. s.nce,on one hand,they have the mos. complete controllability *** the other hand,they can be nearly-controllable even if controllability ***,controllability of the s.s.ems.w.th pos.tive control inputs.is.s.udied and neces.ary and s.fficient algebraic criteria for pos.tive-controllability and pos.tive-near-controllability are ***,controllable canonical forms.and nearly-controllable canonical forms.of the s.s.ems.are pres.nted,res.ectively,w.ere the corres.onding trans.ormation matrices.are als. explicitly *** are given to demons.rate the effectivenes. of the derived controllability criteria and controllable canonical forms.

关键词： Canonical forms controllability dis.rete-time bilinear s.s.ems near-controllability pos.tive control inputs