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贵金属 2012年第A1期33卷 45-47页

作者： BORYAg.NA I. v. v.LCHKOv. E. v. BUSLAEv. T. M. LOBANOv. U. A. ehrlich g. v. OJSC "SIC 'Supermetal'" Moscow Russia Moscow State Univ.rsity of Fine Chemical Technolog. named after M.v. Lomonosov.(MITHT) Moscow Russia Moscow State Univ.rsity (MSU) Moscow Russia

The adsorption of Pd(Ⅱ), Pt(Iv. and Cu(Ⅱ) in static and dynamic conditions on chemically modified silica containing.sulfide sulfur (number of g.afted functional g.oups of the sorbent was 0.2 (CMS-S 0.2) and 0 3 mmol/g.(CMS-S 0.3)) was studied. It is established that an increase in the acidity of the sorption of Pd(Ⅱ) and Pt(Ⅳ) decreases, whereas the Cu(Ⅱ) does not chang.. Time to reach the constant v.lues of the sorption is 15 min. In equal conditions, the sorption decreases in the number of Pd(Ⅱ)>Pt(Iv.>Cu(Ⅱ). Based on retriev.d data sug.ested that the sorption of Pd(Ⅱ) proceeds according.the coordination mechanism. In the case of sorption from solutions with a hig. palladium content can be polymerization of adsorbed complexes in the sorbent phase. Worked out the optimal conditions for the separation of pairs of Pd(Ⅱ)-Pt(Ⅳ) and Pd(Ⅱ)-Cu(Ⅱ) under dynamic conditions with the extraction of palladium(Ⅱ) in the eluate is abov. 95%.

关键词： sorption palladium platinum copper sorbent separation chelation desorption.

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of g.otechnical Structures

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Computer Modeling.in Eng.neering.& Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.v.Ramana Department of Civ.l Eng.neering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses sig.ificant risks to the stability of g.otechnical structures *** understanding.of the liquefaction trig.ering.and the post-failure larg. deformation behav.our is essential for desig.ing.resilient *** present study dev.lops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of g.otechnical *** coupled flowdeformation behav.our of soils subjected to cyclic loading.is described using.the PM4Sand model implemented in a three-phase,sing.e-layer SPH framework.A stag.ered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energ. modes and tensile ***,non-reflecting.boundary conditions for seismic analysis of semi-infinite soil domains using.the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a lev.l g.ound site,and liquefaction-induced failure of the Lower San Fernando *** ag.eement for liquefaction trig.ering.and post-failure behav.our demonstrates that the SPH framework can be utilised to assess the effect of seismic loading.on field-scale g.otechnical *** present study also serv.s as the basis for future adv.ncements of the SPH method for applications related to earthquake g.otechnical eng.neering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

Synthesis of Pharmaceutical Intermediates by Toluene Benzylation ov.r Heteropoly Acids on Different Support

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Journal of Natural g.s Chemistry 2007年第2期16卷 186-192页

作者： v. v. Bokade g. D. Yadav Catalysis Div.sion National Chemical LaboratoryPune 411008India University Institute of Chemical TechnologyMumbai-19India Univ.rsity Institute of Chemical Technolog. Mumbai-19India

Selectiv. formation of pharmaceutical intermediates like diphenylmethane, dimethyldiphenylmethane, benzyl toluene and benzoic acid by liquid phase, toluene benzylation with benzyl chloride as a benzylating.ag.nt, was systematically studied ov.r plane clay （K-10, montmorillonite）, plane H-Beta, plane MFI structured titanosilicate （TS-1） and heteropoly acids [HPA, namely dodecatung.tophosphoric acid [H3PO4.12WOa-xH2O] （TPA）, dodeca-molybdo phosphoric acid ammonium salt hydrate [H12Mo12N3040P＋aq] （DMAA）, sodium tung.tate hydrated purified [Na12WO4.2H2O] （STH）] supported on clay, H-beta and TS-1. The 20%TPA/Clay, 30%TPA/H-Beta and 30%TPA/TS-1, were observ.d to be the best catalyst samples ov.r plane clay, plane H-Beta and plane TS-1. The catalyst samples are compared with respect to benzyl chloride conv.rsion and selectiv.ties for diphenylmethane, dimethyl-diphenylmethane, benzyl toluene and benzoic acid. The reaction follows the pseudo-first order rate power law model. The apparent rate constants are calculated and compared with the reported ones.

关键词： toluene benzylation benzyl chloride heteropolyacid diphenylmethane dimethyl-diphenyl methane benzyl toluene benzoic acid

Nonlinear dynamics of MEMS turning.fork g.roscope

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Science China(Technolog.cal Sciences) 2011年第5期54卷 1078-1083页

作者： Yu. g. MARTYNENKO I. v. MERKURYEv.v. v. PODALKOv Institute of Mechanics Lomonosov Moscow State University Moscow Power Eng.neering.Institute (Technical Univ.rsity)

Accuracy improv.ment of MEMS g.ros requires not only microelectronic dev.lopment but also the inv.stig.tions of th mathematical model of sensitiv. element dynamics. In the present paper, we study the errors of the v.brating.microg.roscop which arise because of nonlinear dynamics of a sensitiv. element. A MEMS tuning.fork g.roscope with elastic rods is consid ered. Nonlinear differential equations of bending.v.brations of sensitiv. element on the mov.ng.basis are deriv.d. Free nonlin ear v.brations of g.roscopes as the flexible rod are studied. Nonlinear dynamics of g.roscope on the mov.ng.basis are inv.sti g.ted by asymptotic two scales method. Sensitiv. element frequencies split on two frequencies resulted from slowly chang.n ang.lar v.locity are taken into account in the equations of zero approximation. The differential equations for slowly chang.n amplitudes and phases of two normal wav.s of the oscillations measured by capacitor g.ug.s and an electronic contour of th dev.ce are obtained from the equations of the first approximation.

关键词： control of g.ro oscillations split of frequencies identification av.rag.ng.method two scales method stability

Effect of machining.parameters on edg.-chipping.during.drilling.of g.ass using.g.inding.aided electrochemical discharg. machining.（g.ECDM）

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Adv.nces in Manufacturing 2018年第2期6卷 215-224页

作者： v. g. Ladeesh R. Manu Department of Mechanical Eng.neering National Institute of Technology Calicut Calicut Kerala 673601 India

The problem of eliminating.edg.-chipping.at the entrance and exit of the hole while drilling.brittle materials is still a challeng.ng.task in different industries. g.inding. aided electrochemical discharg. machining.（g.ECDM） is a promising.technolog. for drilling.adv.nced hard-to-ma- chine ceramics, g.ass, composites, and other brittle mate- rials. Edg.-chipping.at the entrance of the hole can be fully eliminated by optimizing.the machining.parameters of g.ECDM. Howev.r, edg.-chipping.at the exit of the hole is difficult to eliminate during.the drilling.of ceramics and g.ass. This inv.stig.tion sug.ests some practical ways to reduce edg.-chipping.at the exit of the hole. For this pur- pose, a three-dimensional finite element model was dev.loped, and a coupled field analysis was conducted to study the effect of four parameters, i.e., cutting.depth, support leng.h, applied v.ltag., and pulse-on time, on the maximum normal stress in the reg.on where the edg.- chipping.initiates. The model is capable of predicting.the edg.-chipping.thickness, and the results predicted by the model are in close ag.eement with the experiment results. This inv.stig.tion recommends the use of a low v.ltag. and low pulse-on time at the hole entrance and exit when applying.g.ECDM to reduce the edg.-chipping.thickness. Moreov.r, the use of a full rig.d support in the form of a base plate or sacrificial plate beneath the workpiece can postpone the initiation of chipping.by prov.ding.support when the tool reaches the bottom layer of the workpiece, thereby reducing.the edg.-chipping.thickness.

关键词： g.inding.aided electrochemical discharg.machining.(g.ECDM) Finite element analysis Edg.-chipping.- Maximum normal stress

Lanthanide NIR luminescence for telecommunications, bioanalyses and solar energ. conv.rsion

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Journal of Rare Earths 2010年第6期28卷 824-842页

作者： Jean-Claude g. Bünzli Sv.tlana v. Eliseev. cole Polytechnique Fédérale de Lausanne Institute of Chemical Sciences and Engineering WCU Professor Korea University Center for Next Generation Photovoltaic Systems Katholieke Univ.rsiteit Leuv.n Department of Chemistry Laboratory of Coordination Chemistry

Present-day adv.nced technolog.es heav.ly rely on the exciting.mag.etic and spectroscopic properties of lanthanide ions. In particular, their ability to g.nerate well-characterized and intense near-infrared (NIR) luminescence is exploited in any modern fiber-optic telecommunication network. In this feature article, we first summarize the whereabouts underlying.the desig. of hig.ly luminescent NIR molecular edifices and materials. We then focus on describing.the main trends in three applications related to this spectral rang.: telecommunications, biosciences, and solar energ. conv.rsion. In telecommunications, efforts concentrate presently on g.tting.easily processable polymer-based wav.g.ide amplifiers. Upconv.rsion nanophosphors emitting.in the v.sible after NIR excitation are now ubiquitous in many bioanalyses while their application to bio-imag.ng.is still in its early stag.s; howev.r, hig.ly sensitiv. NIR-NIR systems start to be at hand for both in v.tro and in v.v. imag.ng. as well as dual probes combining.mag.etic resonance and optical imag.ng. Finally, both silicon-based and dye-sensitized solar cells benefit from the downconv.rsion and upconv.rsion capabilities of lanthanide ions to harv.st Uv.and NIR solar lig.t and to boost the ov.rall quantum efficiency of these next-g.neration dev.ces.

关键词： lanthanide luminescence near-infrared luminescence telecommunications bioanalysis solar energ. conv.rsion solar cell upconv.rsion downconv.rsion

Influences of diffusion bonding.process parameters on bond characteristics of Mg.Cu dissimilar joints

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Transactions of Nonferrous Metals Society of China 2010年第6期20卷 997-1005页

作者： g. MAHENDRAN v. BALASUBR AMANIAN T. SENTHILv.LAN Department of Mechanical Eng.neering V.R.S. College of Engineering and Technology Centre for Materials Joining.& Research (CEMAJOR) Department of Manufacturing Engineering Annamalai University Department of Mechanical Eng.neering Pondicherry Engineering College

In many circumstances,dissimilar metals hav. to be bonded tog.ther and the resulting.joint interfaces must typically sustain mechanical and/or electrical forces without failure,which is not possible by fusion welding.*** melting.points of mag.esium(Mg.and copper(Cu)hav. a sig.ificant difference(nearly 400℃)and this may lead to a larg. difference in the microstructure and joint performance of Mg.Cu ***,diffusion bonding.can be used to join these alloys without much *** work analyses the effect of parameters on diffusion layer thickness,hardness and streng.h of mag.esium-copper dissimilar *** experiments were conducted using.three-factor,fiv.-lev.l,central composite rotatable desig. *** relationships were dev.loped to predict diffusion layer thickness,hardness and streng.h using.response surface *** is found that bonding.temperature has predominant effect on bond *** fabricated at a bonding.temperature of 450℃, bonding.pressure of 12 MPa and bonding.time of 30 min exhibited maximum shear streng.h and bonding.streng.h of 66 and 81 MPa, respectiv.ly.

关键词： diffusion bonding mag.esium alloy copper alloy shear streng.h bonding.streng.h diffusion layer thickness interface hardness

Semantic Seg.entation of Lumbar v.rtebrae Using.Meijering.U-Net(MU-Net)on Spine Mag.etic Resonance Imag.s

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Computer Modeling.in Eng.neering.& Sciences 2025年第1期142卷 733-757页

作者： Lakshmi S v.v.Shiloah Elizabeth Darmanayag.m Sunil Retmin Raj Cyril Department of Computer Science and Eng.neering College of Engineering GuindyAnna UniversityChennai600025India Department of Information Technolog. Madras Institute of TechnologyAnna UniversityChrompetChennai600044India

Lower back pain is one of the most common medical problems in the world and it is experienced by a hug. percentag. of people *** to its ability to produce a detailed v.ew of the soft tissues,including.the spinal cord,nerv.s,interv.rtebral discs,and v.rtebrae,Mag.etic Resonance Imag.ng.is thoug.t to be the most effectiv. method for imag.ng.the *** semantic seg.entation of v.rtebrae plays a major role in the diag.ostic process of lumbar *** is difficult to semantically partition the v.rtebrae in Mag.etic Resonance Imag.s from the surrounding.v.riety of tissues,including.muscles,lig.ments,and interv.rtebral discs.U-Net is a powerful deep-learning.architecture to handle the challeng.s of medical imag. analysis tasks and achiev.s hig. seg.entation *** work proposes a modified U-Net architecture namely MU-Net,consisting.of the Meijering.conv.lutional layer that incorporates the Meijering.filter to perform the semantic seg.entation of lumbar v.rtebrae L1 to L5 and sacral v.rtebra ***-colour mask imag.s were g.nerated and used as g.ound truth for training.the *** work has been carried out on 1312 imag.s expanded from T1-weig.ted mid-sag.ttal MRI imag.s of 515 patients in the Lumbar Spine MRI Dataset publicly av.ilable from Mendeley *** proposed MU-Net model for the semantic seg.entation of the lumbar v.rtebrae g.v.s better performance with 98.79%of pixel accuracy(PA),98.66%of dice similarity coefficient(DSC),97.36%of Jaccard coefficient,and 92.55%mean Intersection ov.r Union(mean IoU)metrics using.the mentioned dataset.

关键词： Computer aided diag.osis(CAD) mag.etic resonance imag.ng.MRI) semantic seg.entation lumbar v.rtebrae deep learning U-Net model

Hig. Resolution Spectroscopy of Halo Stars in the Near Uv.and Blue Reg.on I. Spectra in the Wav.leng.h Reg.on 3550-5000 A

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Chinese Journal of Astronomy and Astrophysics 2006年第5期6卷 579-587页

作者： v. g. Klochkov. g.ng.Zhao S. v. Ermakov.v. E. Panchuk National Astronomical Observ.tories Chinese Academy of Sciences Beijing 100012 Special Astrophysical Observ.tory Russian Academy of Sciences Nighnij Arkhyz 369167Karachai-Cherkessia Russia

An atlas of hig. resolution （R = 60 000） CCD-spectra in the wav.leng.h rang. 3500-5000A is presented for four objects in metallicity rang. -3.0 〈 [Fe/H] 〈 -0.6, temperature rang. 4750 〈 Teff 〈 5900K, and surface g.av.ty rang. 1.6 〈 Ig. 〈 5.0. We describe the calibration of the stellar atmospheric parameters using.Alonso＇s formula based on the method of infrared flux and outline the determination of the abundances of a total number of 25 chemical elements. An analysis of the abundance determination errors for different chemical elements is carried out, and a method is prov.ded for the observ.tions and reduction of spectral material. Properties of the method of producing.an atlas of spectra and line identifications are described.

关键词： stars halo stars - stars g. K-type - stars spectra - stars Uv.spectra

Metasurfaces: physics and applications in wireless communications

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National Science Rev.ew 2023年第8期10卷 48-63页

作者： v.sileios g. Atalog.ou Sajjad Tarav.ti g.org. v. Eleftheriades The Edward S.Rog.rs Sr.Department of Electrical and Computer Eng.neering University of Toronto Clarendon Laboratory Department of Physics University of Oxford

The ev.r increasing.number of wireless dev.ces and systems has led to a crowded spectrum and increased the demand for v.rsatile and multi-functional wireless apparatuses. Recently, metasurfaces hav. been explored as a prominent technolog.cal solution to the current paradig. of spectrum scarcity by opportunistically sharing.the spectrum with v.rious users. In g.neral, metasurfaces are passiv./dynamic,ultra-compact, multi-functional and prog.ammable structures that are capable of both reciprocal and nonreciprocal sig.al-wav. transmissions. The controllability and prog.ammability of such metasurfaces are g.v.rned throug. DC bias and occasionally a radio-frequency modulation applied to the activ. components of the unit cells of the metasurface, e.g. diodes and transistors. This article ov.rv.ews some of the recently proposed passiv. and dynamic metasurfaces and shows that metasurfaces can enhance the performance of wireless communication systems thanks to their unique physical features such as real-time sig.al coding.nonreciprocal-beam radiation, nonreciprocal beamsteering.amplification and adv.nced pattern-coding.multiple access communication.

关键词： metasurface beamsteering beamforming wireless communication time modulation wav. eng.neering