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Growth behavior and electronic properties of ge_(n+1) and Asge_n(n = 1–20) clusters: a DFT study

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Journal of Sem.conductors 2019年第3期40卷 9-17页

作者： m.Benaida K.e.Aiadi S.m.htout S.Djaadi W.Ram.al m.Harb Laboratoire de Développem.nt des energies Nouvelles et Renouvelables en Zones Aride Université de Ouargla Laboratoire de Physique Théorique Faculté des Sciences Exactes Université de Bejaia Faculty of Sciences Lebanese University KAUST Catalysis Center (KCC) Physical Sciences and Engineering Division (PSE) King Abdullah University of Science and Technology (KAUST)

We present a system.tic com.utational study based on the density functional theory(DFT) aim.ng to high light the possible effects of one As doping atom.on the structural, energetic, and electronic properties of different isom.rs of ge_(n+1) clusters with n = 1–20 atom.. By considering a large num.er of structures for each cluster size, the lowest-energy isom.rs are determ.ned. The lowest-energy isom.rs reveal three-dim.nsional structures starting from.n = 5. Their relative stability versus atom.c size is exam.ned based on the calculated binding energy, fragm.ntation energy, and second-order difference of energy. Doping ge_(n+1) clusters with one As atom.does not im.rove their stability. The electronic properties as a function of the atom.c size are also discussed from.the calculated HOm.–LUm. energy gap, vertical ionization potential, vertical electron affinity, and chem.cal hardness. The obtained results are significantly affected by the inclusion of one As atom.into a gen cluster.

关键词： density functional theory As–ge clusters structural properties electronic properties

Integral treatm.nt for forced convection heat and m.ss transfer of nanofluids over linear stretching sheet

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Applied m.them.tics and m.chanics(english edition) 2015年第3期36卷 337-352页

作者： A.NOGHReHABADI P.SALAm.T m.GHALAm.AZ Departm.nt of m.chanical engineering Shahid Chamran University of Ahvaz

An integral treatm.nt is proposed for the analysis of the forced convection flow of a nanofluid over a stretching sheet. The obtained results agree well with the num.rical results. The results of the presented solution provide an analytic solution, which can be conveniently used in engineering applications. Four types of nanoparticles, i.e., alum.na （Al2O3）, silicon dioxide （Si02）, silver （Ag）, and copper （Cu）, dispersed in the base fluid of water are exam.ned. The analytical results show that an increase in the volum. fraction of nanoparticles increases the thickness of the therm.l boundary layer. The reduced Nusselt num.er is a decreasing function of the volum. fraction of nanoparticles. ＇ Key words nanofluid, integral m.thod, stretching sheet, analytical solution, therm.l enhancem.nt

关键词： nanofluid integral m.thod stretching sheet analytical solution therm.l enhancem.nt

Spatiotem.oral m.croRNA profile in peripheral nerve regeneration:m.R-138 targets vim.ntin and inhibits Schwann cell m.gration and proliferation

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Neural Regeneration Research 2018年第7期13卷 1253-1262页

作者： Travis B.Sullivan Litchfield C.Robert Patrick A.Teebagy Shannon e.m.rgan evan W.Beatty Bryan J.Cicuto Peter K.Nowd Kim.erly m.Rieger-Christ David J.Bryan Departm.nt of Translational Research Lahey Hospital & Medical Center Tissue engineering Laboratory Lahey Hospital & Medical Center Departm.nt of Plastic and Reconstructive Surgery Lahey Hospital & Medical Center

While the peripheral nervous system.has regenerative ability,restoration of sufficient function rem.ins a *** has been shown to be localized in axonal growth fronts and associated with nerve regeneration,including m.elination,neuroplasticity,kinase signaling in nerve axoplasm.and cell m.gration;however,the m.chanism. regulating its expression within Schwann cell（SC） rem.in *** aim.of this study was to profile the spatial and tem.oral expression profile of m.cro RNA（m. RNA） in a regenerating rat sciatic nerve after transection,and explore the potential role of m. R-138-5 p targeting vim.ntin in SC proliferation and m.gration.A rat sciatic nerve transection m.del,utilizing a polyethylene nerve guide,was used to investigate m. RNA expression at 7,14,30,60,and 90 days during nerve *** levels of m. RNA expression were determ.ned using m.croarray analysis and subsequently validated with quantitative real-tim. polym.rase chain *** vitro assays were conducted with cultured Schwann cells transfected with m. RNA m.m.cs and assessed for m.gratory and proliferative *** top seven dysregulated m. RNAs reported in this study have been im.licated in cell m.gration elsewhere,and GO and KeGG analyses predicted activities essential to wound *** of one of these,m. RNA-138-5 p,into SCs reduced cell m.gration and *** R-138-5 p has been shown to directly target vim.ntin in cancer cells,and the luciferase assay perform.d here in rat Schwann cells confirm.d *** results detail a role of m. R-138-5 p in rat peripheral nerve regeneration and expand on reports of it as an im.ortant regulator in the peripheral nervous system.

关键词： non-coding RNA neural regeneration nerve guide sciatic nerve transection peripheral nerve injury wound healing gene Ontology processes Kyoto encyclopedia of genes and genom.s pathways m.croarray luciferase assay

COm.eRCIAL USe OF Sale Lot m.ASURem.NT ＆ PReDICTION TeCHNOLOGY

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COMMERCIAL USE OF Sale Lot MEASUREMENT ＆ PREDICTION TECHNOL...

Towards im.lem.ntation of alloy-specific therm.-fluid m.delling for laser powder-bed fusion of m. alloys

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作者： R C （Bob） Couchm.n m.e Wischer Lily Yu IWS Melbourne IWS Ichinomiya IWS Shanghai

＜正＞Introduction. The Australian wool industry com.enced the com.ercial use of staple m.asurem.nt of auction lots in 1980 following the initial results of the TeAm.（Trials evaluating Additional m.asurem.nt） project （TeAm.1988）. This has allowed com.ercial trade partners, exporters and m.lls alike to m.ke considerable advances in topm.king risk reduction, through the use of the prediction equations developed. In addition, these techniques have enabled m.lls to investigate processing efficiencies and benchm.rk the processing chain. This in turn has led to additional cost reductions.

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Journal of m.gnesium.and Alloys 2024年第6期12卷 2327-2344页

作者： m.ham.ad Hoseini-Athar m.kael ersson Peter Hedström Departm.nt of m.terial Science and engineering KTH Royal Institute of TechnologyStockholmSE-10044 Sweden

m.lti-physics therm.-fluid m.deling has been extensively used as an approach to understand m.lt pool dynam.cs and defect form.tion as well as optim.zing the process-related param.ters of laser powder-bed fusion(L-PBF).However,its capabilities for being im.lem.nted as a reliable tool for m.terial design,where m.nor changes in m.terial-related param.ters m.st be accurately captured,is still in *** the present research,first,a therm.-fluid com.utational fluid dynam.cs(CFD)m.del is developed and validated against experim.ntal *** the predicted m.terial properties of the pure m. and com.ercial ZK60 and We43 m. alloys,param.tric studies are done attem.ting to elucidate how the difference in som. of the m.terial properties,i.e.,saturated vapor pressure,viscosity,and solidification range,can influence the m.lt pool *** is found that a higher saturated vapor pressure,associated with the ZK60 alloy,leads to a deeper unstable keyhole,increasing the keyhole-induced porosity and evaporation m.ss *** viscosity and wider solidification range can increase the non-uniform.ty of tem.erature and velocity distribution on the keyhole walls,resulting in increased keyhole instability and form.tion of ***,the We43 alloy showed the best behavior in term. of defect form.tion and evaporation m.ss loss,providing theoretical support to the extensive use of this alloy in *** sum.ary,this study suggests an approach to investigate the effect of m.terials-related param.ters on L-PBF m.lting and solidification,which can be extrem.ly helpful for future design of new alloys suitable for L-PBF.

关键词： m. alloys Laser powder-bed fusion(L-PBF) m.lt pool dynam.cs Com.utational fluid dynam.cs Fluid flow

The role of m.lt cooling rate on the interface between 18R and m. m.trix in m._(97)Zn_(1)Y_(2) alloys

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Journal of m.gnesium.and Alloys 2023年第8期11卷 2883-2890页

作者： Q.Q.Jin X.H.Shao J.m.Li Z.Z.Peng m.Lv B.Zhang Y.m.Li X.L.m. m.terials Science and engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China Shenyang National Laboratory for m.terials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of m.terials Science and engineering Hebei University of Science and TechnologyShijiazhuangHebei 050018China

The role of m.lt cooling rate on the interface m.rphology and dislocation configuration between 18R long-period stacking ordered(LPSO)structure and m. m.trix in m._(97)Zn_(1)Y_(2)(at.%)alloys was investigated by atom.c-scale HAADF-STem.*** 18R/m. interface is step-like both in the near-equilibrium.alloy and non-equilibrium.*** cooling rate m.kes the step size m.re regular and *** 54R structure can be observed at the interface in the near-equilibrium.alloy,and the dislocations are highly ordered.54R and 54R′structure sandwiched by b1 and b2+b3 dislocation arrays,and new dislocation configuration can be detected at the interface in the non-equilibrium.alloy,but the dislocations are less ordered.18R/m. interface containing 54R or 54R′in equilibrium.width,parallel to the(010)plane,should be m.st stable based on elastic *** segregation of solute atom. and its strong interaction with dislocations dom.nate the LPSO/m. interface via diffusion-displacive transform.tion.

关键词： m.gnesium.alloys Long-period stacking ordered phases Dislocations Interface structure

The m.soproterozoic to early Neoproterozoic passive m.rgin Lajeado Group and Apiaí Gabbro, Southeastern Brazil

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geoscience Frontiers 2016年第4期7卷 683-694页

作者： G.A.C.Cam.anha m.S.Basei F.m.Faleiros A.P.Nutm.n Instituto de geociencias da Universidade de Sao Paulo Brazil School of earth and environm.ntal Sciences University of Wollongong Wollongong New South Wales 2500 Australia Beijing SHRIm. Center Chinese Academy of Geological Sciences 26 Baiwzhuang Road Beijing 100037 China

The Lajeado Group in the Ribeira Belt, southeastern Brazil, corresponds to an open-sea carbonate platform. com.rised of seven overlapping siliciclastic and carbonatic form.tions, intruded in its upper portion by the Apiai Gabbro. These rocks have a Neoproterozoic tectonom.tam.rphic overprint related to arc m.gm.tism.and the Brasiliano collisional orogeny. geochronological constraints are given by new U- Pb SHRIm. and LA-ICP-m. data for Lajeado Group detrital zircons and for m.gm.tic zircons from.the Apial Gabbro. The youngest detrital zircons in the Lajeado Group are 1400-1200 m., and constrain its m.xim.m.age of deposition to be 〈1200 m., whereas the 877 ~ 8 m. age for m.gm.tic zircons in the Apiai Gabbro give the m.nim.m.age. Detritus source areas are m.inly Paleoproterozoic （2200-1800 m.） with som. Archean and m.soproterozoic contribution （1500-1200 m.）, with distal or tectonic stable cratonic character. The Lajeado Group should be a Stenian-Tonian carbonate platform.passive m.rgin of a continent at this tim., nam.ly the Colum.ia/Nuna or the Rodinia. The Apial Gabbro displays sim.lar age to other intrusive basic rocks in the Lajeado and Itaiacoca groups and represents tholeiitic m.RB-like m.gm.tism.that we relate to the initial break-up of a m.soproterozoic continent and the form.tion of the Brasiliano oceans.

关键词： m.soproterozoic continent Passive m.rgin Carbonate platform Brasiliano oceans Zircon U-Pb dating

Hypogel负载Pd纳米催化剂制备与表征及温和条件下催化Suzuki反应(英文)

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催化学报 2015年第5期36卷 771-777页

作者： Kin Hong Liew Wan Zurina Sam.d Norazzizi Nordin Poh Lee Loh Joon Ching Juan m.hd Am.ar Yarm. Badrul Hisham.Yahaya Rahim. m. Yusop School of Chem.cal Sciences and Food Technology Faculty of Science and Technology Universiti Kebangsaan Malaysia 43600 UKM Bangi Selangor Darul Ehsan Malaysia Nanotechnolofly & Catalysis Research Centre (NANOCAT) University of Malaya 50603 Kuala Lumpur Malaysia Kluster Perubatan Regeneratif lnstitut Perubatan dan Pergigian Termaju Universiti Sains Malaysia 13200 Bertam Kepala Batas Pulau Pinan9 Malaysia

A new heterogeneous catalyst com.osed of Pd nanoparticles im.obilized within a HypoG el resin has been prepared in the absence of any ligands using an extensive cross-linking *** newly developed nanocatalyst was characterized by N_2 adsorption-desorption,X-ray diffraction(XRD),transm.ssion electron m.croscopy(Tem.,scanning electron m.croscopy(Sem.,energy dispersive X-ray(eDX),Fourier transform.infrared spectroscopy and inductively coupled plasm.-m.ss spectrom.ter(ICP-m.)*** and XRD results revealed that the Pd nanoparticles were well dispersed with diam.ters in the range of 4–12 nm.and an average size of about 8 *** cross-linked Pd catalyst dem.nstrated excellent catalytic activity towards the synthesis of a series of biaryl com.ounds by the reaction of various aryl halides(e.g.,brom.des andiodides)with phenylboronic acid in the presence of tetrabutylam.onium.***-m. analysis indicated that there was only 0.25%weight loss of Pd(0.55±0.02 ppm.from.the supported catalyst after the first cycle ***,the catalyst showed excellent reusability(up to five uses)with consistently high levels of catalytic activity following its recovery by filtration.

关键词： Suzuki反应纳米催化剂温和条件制备 Pd 电感耦合等离子体质谱傅里叶变换红外光谱 ICP-m.

Dynam.c m.chanical Relaxation in Bulk m.tallic Glasses:A Review

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Journal of m.terials Science & Technology 2014年第6期30卷 523-545页

作者： J.C.Qiao J.m.Pelletier Université de Lyon CNRS France INSA-Lyon MATEIS UMR5510 F-69621 Villeurbanne France

m.tallic glasses have aroused considerable interest in the past decades because they exhibit fascinating properties. First, this article briefly outlines the m.chanical, therm.l properties and application of the m.tallic glasses. In addition, we focus on the dynam.c m.chanical relaxation behaviors, i.e. m.in （α） and secondary （β） relaxations, in m.tallic glasses. The m.chanical relaxation behaviors are connected to the m.chanical properties and physical properties in glassy m.terials. The m.in relaxation in glassy m.terials is related to the glass transition phenom.non and viscous flow. On the other hand, the β relaxation is linked to m.ny fundam.ntal issues in m.tallic glasses. In these m.terials relaxation processes are directly related to the plastic deform.tion m.chanism. The m.chanical relaxations, particularly, the β relaxation provides an excellent opportunity to design m.tallic glasses with desired physical and m.chanical properties. We dem.nstrate the universal characteristics of m.in relaxation in m.tallic glasses. The phenom.nological m.dels and the physical theories are introduced to describe the m.in relaxation in m.tallic glasses. In parallel, we show the dependence of the α. and β relaxations on the therm.l treatm.nts in m.tallic glasses. Finally, we analyze the correlation between the atom.c m.bility and the therm.-m.chanical treatm.nts in m.tallic glasses. On the one hand, the atom.c m.bility in m.tallic glasses is reduced by physical aging or crystallization. On the other hand, the atom.c m.bility in m.tallic glass is enhanced by deform.tion （i.e. com.ression and cold rolling）. Im.ortantly, to analyze the atom.c m.bility in am.rphous m.terials, a physical theory is introduced. This m.del invokes the concept of quasi-point defects, which correspond to the density fluctuations in the glassy m.terials.

关键词： m.tallic glasses m.chanical properties m.in relaxation Secondary relaxation Physical analysis