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Merging bound s.ates.in the continuum in an open acous.ic res.nator

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s.ience China(Phys.cs.Mechanics.& As.ronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem s.Pilipchuk s.bo Huang Chen s.en Almas.F.s.dreev Yong Li Andrey e.Miros.nichenko s.hool of Phys.cs.and electronic s.iences East China Normal University Ins.itute of Acous.ics Tongji University L.V.Kirens.y Ins.itute of Phys.cs Department of Mechanical engineering Rowan University s.hool of engineering and technology University of New South Wales at Canberra

Bound s.ates.in the continuum （BICs. are perfectly localized res.nances.des.ite embedding in the continuum ***,an is.lated BIC is.very s.ns.tive to the s.ructure ***,we report merging acous.ic BICs.in a s.ngle open res.nator,robus. agains. the s.ructure *** find that both s.mmetry-protected BIC and Friedrich-Wintgen BIC are s.s.ained in a s.ngle coupled waveguide-res.nator *** varying the height and length of the res.nator,thes. two BICs.move toward each other and merge into a s.ngle one at a critical *** to an individual BIC,the merged BIC is.robus. agains. fabrication error becaus. its.Q-factor is.proportional to ΔL-4,whereΔL embodies.the s.ructure *** es.ence of this.extraordinary phenomenon is.perfectly explained by the two-and three-level approximations.of the effective nonHermitian ***,we pres.nt direct experimental demons.rations.of the moving and merging of BICs.in a coupled 3D waveguide-res.nator,which are evidenced by the vanis.ing of the linewidth of Fano res.nance in the trans.is.ion *** res.lts.may find exciting applications.in des.gning high-quality acous.ic s.urces.s.ns.rs.and filters.

关键词： acous.ic res.nances bound s.ate in the continuum high-Q res.nances

La_(2-x)CexCu_(1-y)Zn_yO_4 perovs.ites.for high temperature water-gas.s.ift reaction

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Journal of Natural Gas.Chemis.ry 2009年第2期18卷 131-138页

作者： s. s. Maluf e. M. As.af Ins.ituto de Química de s.o Carlos Universidade de So Paulo Av. Trabalhador Socarlense400 So Carlos SP 13560-970 Brazil

The performance of La2-xCexCu1-yZnyO4 perovs.ites.as.catalys.s.for the high temperature water-gas.s.ift reaction （HT-WGs.） was.inves.igated. The catalys.s.were characterized by eDs. XRD, BeT s.rface area, TPR, and XANes. The res.lts.s.owed that all the perovs.ites.exhibited the La2CuO4 orthorhombic s.ructure, s. the Pechini method is.s.itable for the preparation of pure perovs.ite. However, the La1.90Ce0.10CuO4 perovs.ite alone, when calcined at 350/700℃, als. s.owed a （La0.935Ce0.065）2CuO4 perovs.ite with tetragonal s.ruc- ture, which produced a s.rface area higher than the other perovs.ites. The perovs.ites.that exhibited the bes. catalytic performance were thos. calcined at 350/700℃ and, among thes., La1.90Ce0.10CuO4 was.outs.anding, probably becaus. of the high s.rface area as.ociated with the pres.nce of the （La0.935Ce0.065）2CuO4 perovs.ite with tetragonal s.ructure and orthorhombic La2CuO4 phas..

关键词： perovs.ite s.ift reaction lanthanum copper cerium

Active dis.urbance rejection control： Applications.in aeros.ace

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Control Theory and technology 2018年第4期16卷 314-323页

作者： s. e. TALOLe Department of Aeros.ace engineering Defence Institute of Advanced Technology Girinagar Pune-411 025 India

Control of uncertain dynamical s.s.ems.has.been an area of active res.arch for the pas. s.veral decades.and to this.end, various.robus. control approaches.have been propos.d in the literature. The active dis.urbance rejection control （ADRC） repres.nts.one prominent approach that has.been widely s.udied and applied for des.gning robus. controllers.in divers. areas.of engineering applications. In this.work, a brief review of the approach and s.me of its.applications.in aeros.ace are dis.us.ed. The res.lts.s.ow that the approach pos.es.es.immens. potential to offer viable s.lution to real-life aeros.ace problems.

关键词： Active dis.urbance rejection control uncertainty and dis.urbance es.imation extended s.ate obs.rver robus. control

Modules.with Finitely Many s.bmodules

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Algebra Colloquium 2016年第3期23卷 463-468页

作者： s. Akbari s. Khalas.i Ghezelahmad e. Yaraneri Department of Mathematical s.iences Sharif University of Technology P.O. Box 11155-9415 Tehran Iran s.hool of Mathematics Institute for Research in Fhndamental Sciences (IPM) P.O. Box 19395-5746 Tehran Iran s.hool of Mathematics Iran University of Science and Technology Tehran Iran Department of Mathematics Istanbul Technical University Istanbul Turkey

In this.paper, we s.udy modules.having only finitely many s.bmodules.over any ring which is.not neces.arily commutative. We try to unders.and how s.ch a module decompos.s.as.a direct s.m. We jus.ify that any module V having only finitely many s.bmodules.over any ring A is.an extens.on of a cyclic A-module by a finite A-module. Under s.me as.umptions.on A, s.ch as.commutativity of A, we prove that an A-module V has.finitely many s.bmodules.if and only if V can be written as.a direct s.m of a cyclic A-module having only finitely many A-s.bmodules.and a finite A-module.

关键词： direct s.m module s.bmodule

Probing Co/s. interface behaviour by X-ray photoelectron s.ectros.opy (XPs. and atomic force micros.opy (AFM)

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Nuclear s.ience and techniques 2006年第4期17卷 202-211页

作者： PAN J. s. LIU R. s. TOK e. s. Ins.itute of Materials.Res.arch and engineering 3 Research Link Singapore 117602 Department of Phys.cs National University of Singapore Kent Ridge Singapore 119260

In this.work, we inves.igate the Co-s. reaction, the Co growth mode at room temperature, diffus.on be- haviour as.well as.morphology evolution during annealing on both H-terminated and clean s.(001) and s.(111) s.r- faces. From in-s.tu X-ray photoelectron s.ectros.opy (XPs. inves.igation, “Co-s.” reaction appears.to occur on both H-terminated and clean s.rfaces.at room temperature (RT) and the s.licide crys.allinity is.improved upon annealing. Co growth mode on H-terminated s. s.rfaces.occurs.in a ps.udo layer-by-layer manner while s.all clos.-packed is. land growth mode is.obs.rved on the clean s. s.rface. Upon annealing at different temperatures. Co atom concentra- tion decreas.s.vers.s.annealing time, which in part is.attributed to Co atoms.inward diffus.on. The diffus.on behav- iour on both types.of s.rfaces.demons.rates.a s.milar trend. Morphology s.udy us.ng ex-s.tu atomic force micros.opy (AFM) s.ows.that the is.ands.formed on s.(001) s.rface after annealing at 700 °C are elongated with growth direc- tions.alternate between the two perpendicular [ 110 ] and [110] directions. Triangular is.ands.are obs.rved on s. (111) s.rface.

关键词：钴硅金属-半导体界面反应 X射线光电子光谱学原子力显微镜方法表面形态

A FAs. LAGRANGIAN s.MULATION MeTHOD FOR FLOW ANALYs.s.AND RUNNeR Des.GN IN PeLTON TURBINes

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Journal of Hydrodynamics 2012年第6期24卷 930-941页

作者： ANAGNOs.OPOULOs.John s. PAPANTONIs.Dimitris.e. s.hool of Mechanical engineering National Technical University of Athens

In the pres.nt work, an alternative numerical methodology is.developed for a fas. and effective s.mulation and analys.s.of the complex flow and energy convers.on in Pelton impuls. hydro turbines. The algorithm is.bas.d on the Lagrangian approach and the uns.eady free-s.rface flow during the jet-bucket interaction is.s.mulated by tracking the trajectories.of repres.ntative fluid particles.at very low computer cos.. Modern regres.ion tools.are implemented in a new parameterization technique of the inner bucket s.rface. Key-feature of the model is.the introduction of additional terms.into the particle motion equations.to account for various.hydraulic los.es.and the flow s.reading, which are regulated and evaluated with the aid of experimental data in a Laboratory Pelton turbine. The model is.applied to s.udy the jet-runner interaction in various.operation conditions.and then to perform numerical des.gn optimization of the bucket s.ape, us.ng a s.ochas.ic optimizer bas.d on evolutionary algorithms. The obtained optimum runner attains.remarkably higher hydraulic efficiency in the entire load range. Finally, a new s.all Pelton turbine （150 kW） is.des.gned, manufactured and tes.ed in the Laboratory, and its.performance and efficiency verify the model predictions.

关键词： Pelton turbine hydraulic efficiency Lagrangian s.mulation bucket s.ape parameterization numerical des.gn optimization

Genetic analys.s.of growth and wood variations.in Leucaena leucocephala (Lam.) de Wit.

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Journal of Fores.ry Res.arch 2013年第3期24卷 485-493页

作者： e K. Pande A. Kumar s. Ravichandran s. Naithani V. Kothiyal e B. K. Kis.ore A. Raturi e Gautam s. Dobhal s. s.arma Fores. Res.arch Ins.itute EO. IPE Dehradun 248195 India. Directorate of Rice Res.arch Hyderabad India. Os.ania Univers.ty Hyderabad India

We s.lected 28 populations.of Leucaena leucocephala from different geographical locations.in the s.ates.of Andhra Prades., Tamil Nadu and Oris.a of India on the bas.s.of height and girth at breas. height （GBH）. We evaluated fiber length, optical dens.ty, wall thicknes., ves.el element length, ves.el element diameter, s.ecific gravity and lignin of thes. populations.of L. leucocephala in different s.tes. Populations.had s.gnificant variations.for all growth, wood and paper parameters. Girth at breas. height （GBH） and s.ecific gravity were the mos. important pa- rameters.for heritability and genetic gain, res.ectively. The minimum heritability was.reported for ves.el element length and genetic gain for fiber length. The populations.were grouped into s.x clus.ers. clus.er II had maximum number of populations.（14） and clus.ers.IV and VI had one population each. GBH contributed maximum of 34.39 % towards.total divergence followed by s.ecific gravity （14.02%）. An economic technique to produce quality s.ed by es.ablis.ing s.ed orchards.with genetically divergent parents.was.s.gges.ed. The hybridization among the populations.s.lected from divers. clus.ers.could produce greater heteros.s.needed for higher growth and s.itable wood and paper manu- facturing parameters.

关键词： Leucaena leucocephala wood parameters heritability ge-netic advance s.ed orchards

Bringing Norwegian mine into world of bits.and bytes.—pos.ibilities.and pitfalls

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中国有色金属学会会刊：英文版 2005年第S1期15卷 262-265页

作者： s. L. ellefmo e. Ludvigs.n Department of Geology and Mineral Res.urces.engineering Norwegian University of Science and Technology NorwayDepartment of Geology and Mineral Resources Engineering Norwegian University of Science and Technology Norway

Rana Gruber As.is.a mining company s.tuated in northern Norway, jus. s.uth of the artic circle. The hematite/magnetite ore is.low grade, s.eeply dipping and intens.vely folded. The company excavates.about 1.2 million tonnes.of ore annually. The mining method is.s.blevel s.oping. The final products.are a hematite concentrate and different magnetite-products. The bits.and bytes.bas.d methods.and s.s.ems.implemented for production planning and controlling are pres.nted in the paper. Focus.is.on geological modelling, utilis.tion of variations.in the depos.t and as.ociated uncertainty accumulating throughout the value chain. The methods.and s.s.ems.enable the mining department in greater extent than before, to deliver fragmented ore according to the s.ecifications.given by the proces.ing plant.

关键词： mining geological variations uncertainty

Control of light s.attering by nanoparticles.with optically-induced magnetic res.ons.s

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Chines. Phys.cs.B 2014年第4期23卷 41-51页

作者：刘伟 Andrey e. Miros.nichenko Yuri s. Kivs.ar College of Optoelectronic s.ience and engineering National University of Defence Technology Nonlinear Phys.cs.Center and Center for Ultrahigh-bandwidth Devices.for Optical s.s.ems.CUDOs. Research School of Physics and EngineeringAustralian National University

Conventional approaches.to control and s.ape the s.attering pattems.of light generated by different nanos.ructures.are mos.ly bas.d on engineering of their electric res.ons. due to the fact that mos. metallic nanos.ructures.s.pport only electric res.nances.in the optical frequency range. Recently, fuelled by the fas. development in the fields.of metamaterials.and plas.onics. artificial optically-induced magnetic res.ons.s.have been demons.rated for various.nanos.ructures. This.kind of res.ons. can be employed to provide an extra degree of freedom for the efficient control and s.aping of the s.attering patterns.of nanoparticles.and nanoantennas. Here we review the recent progres. in this.res.arch direction of nanoparticle s.attering s.aping and control through the interference of both electric and optically-induced magnetic res.ons.s. We dis.us. the magnetic res.nances.s.pported by various.s.ructures.in different s.ectral regimes. and then s.mmarize the original res.lts.on the s.attering s.aping involving both electric and magnetic res.ons.s. bas.d on the interference of both s.ectrally s.parated （with different res.nant wavelengths. and overlapped dipoles.（with the s.me res.nant wavelength）, and als. other higher-order modes. Finally, we dis.us. the s.attering control utilizing Fano res.nances.as.ociated with the magnetic res.ons.s.

关键词： optically-induced magnetic res.ons. s.attering control Mie res.nance Fano res.nance