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An Efficient Iterativ. Procedure for Solution of Plasm. Loaded Helical Wav.guide Problem.

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chinese Physics Letters 2005年第12期22卷 3123-3125页

作者： v. Babov.c m. Kov.cev.c K. Kanjev.c Departm.nt of Physics Faculty of Science University of Kragujevac Serbia and Montenegro

The behav.our of axially-sym.etric wav.s trav.lling on plasm. filled screened helical coil is com.rehensiv.ly studied by Anicin [J. Phys. D： Appl. Phys. 33 （2000） 1276], where all analytical expressions are deriv.d in the full-wav. theory, but the diagram. are com.uted in the quasistatic approxim.tion. We use an iterativ. procedure to ov.rcom. this lim.tation. The iterativ. procedure is rapid and we hav. prov.n that often the first-order approxim.nt is sufficient to im.rov. defects which are known as im.anent to the quasistatic approxim.tion. The fixed point m.thod appears as the natural choice for num.rical treatm.nt of form.lae which could arise in a broad class of physical problem. usually recognized as guided surface plasm. wav.s.

关键词： Iterativ. m.thods

KINETIC m.DELING OF ESTERIFICATION OF EPOXY RESIN IN THE PRESENCE OF TRIPHENYLPHOSPHINE FOR PRODUCING v.NYL ESTER RESIN: m.chANISTIC RATE EQUATION

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chinese Journal of Polym.r Science 2006年第6期24卷 599-608页

作者： m. Rafizadeh H. Ghasem. v. Haddadi-Asl Polym.r Engineering Departm.nt Amirkabir University of TechnologyP. O. Box 15785-4414TehranIran

Due to its m.chanical properties and ease of use, v.nyl ester resin is enjoying increasing consideration. This resin norm.lly is produced by reaction between epoxy resin and unsaturated carboxylic acid. In the present study, bis-phenol A based epoxy resin and m.thacrylic acid was used to produce v.nyl ester resin. The reaction was conducted under both stoichiom.tric and non-stoichiom.tric conditions in the presence of triphenylphosphine as catalyst. The stoichiom.tric and non-stoichiom.tric experim.nts were conducted at 95, 100, 105 and 110℃ and at 90 and 95℃, respectiv.ly. The first order rate equation and m.chanism.based rate equation were exam.ned. Param.ters are ev.luated by least square m.thod. A com.arison of m.chanism.based rate equation and experim.ntal data show an excellent agreem.nt. Finally, Arrhenius equation and activ.tion energy were presented.

关键词： Esterification Epoxy resin v.nyl ester resin Kinetic Rate equation.

Effect of Ablation Casting on m.crostructure and Casting Properties of A356 Alum.nium.Casting Alloy

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Acta m.tallurgica Sinica(English Letters) 2013年第1期26卷 85-91页

作者： v. Bohlooli m. Shabani m.halli S. m. A. Boutorabi Casting Research Center School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST) Center of Excellence for High Strength Alloys Technology (CEHSAT) School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST)

Recently the Ablation Casting Technology was inv.nted as a new casting process to im.rov. foundry products quality. In this study, the effects of processing v.riables on the porosity content, rnicrostructure and feedability of A356 casting alloy were inv.stigated. Secondary dendrite arm.spacing （SDAS） and eutectic silicon m.r-phologies were studied to ev.luate the influence of Ablation Casting on the rnicrostructure. Casting density was m.asured in order to identify porosity content and feedability of ablated and non-ablated specim.ns. In addition, solidification behav.or of the sam.les was inv.stigated by using therm.l analysis technique. The cooling curv.s and the first deriv.tiv. curv.s were plotted and com.ared with each other. Results showed the ablation process could increase solidification rate significantly. In addition, the m.crostructural ev.dences rev.aled that Ablation Casting process results in m.re fine and hom.geneous structure com.ared to the non-ablated casting. The feedability im.rov.d, SDAS reduced to 35% and porosity content decreased to 3.84 v.l.% by im.lem.nting this process. It concluded the Ablation Casting is an effectiv. process to gain higher quality in alum.num.foundry.

关键词： Ablation Casting A356 alum.nium.alloy m.crostructure Porosity Cooling curv.

Quantum.m.chanical effects in photolum.nescence from.thin crystalline gold film.

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Light(Science & Applications) 2024年第4期13卷 783-794页

作者： Alan R.Bowm.n Alv.ro Rodríguez Echarri Fatem.h Kiani Fadil Iyikanat Ted v.Tsoulos Joel D.Cox Rav.shankar Sundararam.n F.Jav.er García de Abajo Giulia Tagliabue Laboratory of Nanoscience for Energy Technologies(LNET) STIÉcole Polytechnique Fédérale de Lausanne(EPFL)LausanneSwitzerland ICFO–Institut de Ciencies Fotoniques The Barcelona Institute of Science and TechnologyCastelldefels(Barcelona)Spain. m.I–m.x-Born-Institut BerlinGermany. POLIm.–Center for Polariton-driv.n Light–m.tter Interactions University of Southern DenmarkOdense MDenmark. Danish Institute for Adv.nced Study University of Southern DenmarkOdense MDenmark. Departm.nt of m.terials Science&Engineering Rensselaer Polytechnic InstituteTroyNYUSA. Departm.nt of Physics Applied Physicsand AstronomyRensselaer Polytechnic InstituteTroyNYUSA. ICREA–Institucio Catalana de Recerca i Estudis Av.ncats BarcelonaSpain

Lum.nescence constitutes a unique source of insight into hot carrier processes in m.tals,including those in plasm.nic nanostructures used for sensing and energy ***,being weak in nature,m.tal lum.nescence rem.ins poorly understood,its m.croscopic origin strongly debated,and its potential for unrav.ling nanoscale carrier dynam.cs largely ***,we rev.al quantum.m.chanical effects in the lum.nescence em.nating from.thin m.nocrystalline gold ***,we present experim.ntal ev.dence,supported by first-principles sim.lations,to dem.nstrate its photolum.nescence origin(i.e.,radiativ. em.ssion from.electron/hole recom.ination)when exciting in the interband *** m.del allows us to identify changes to the m.asured gold lum.nescence due to quantum.m.chanical effects as the gold film.thickness is ***,such effects are observ.ble in the lum.nescence signal from.flakes up to 40 nm.in thickness,associated with the out-of-plane discreteness of the electronic band structure near the Ferm. *** qualitativ.ly reproduce the observ.tions with first-principles m.deling,thus establishing a unified description of lum.nescence in gold m.nocrystalline flakes and enabling its widespread application as a probe of carrier dynam.cs and light-m.tter interactions in this *** study pav.s the way for future explorations of hot carriers and charge-transfer dynam.cs in a m.ltitude of m.terial system..

关键词： lum.nescence quantum crystalline

Dam.ge m.chanism.of CK2 and IKAROS in Philadelphia Like Acute Lym.hoblastic Leukem.a

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Journal of Biosciences and m.dicines 2024年第4期12卷 49-59页

作者： Ignacio v.lez-Rodríguez v.ctoria Carranza-Aranda Facultad m.xicana de m.dicina Universidad La Salle Tlalpan M&#233xico Hospital General de m.#233 xico Cuauht&#233moc M&#233xico

Acute lym.hoblastic leukem.a (ALL) is characterized by im.ature and poorly differentiated B lym.hocytes in large num.ers in the blood. B cells are distinct from.the cell types inv.lv.d in their dev.lopm.nt (com.on lym.hoid progenitor cells, pro-B cells, pre-B cells, and m.ture cells). The process of B cell m.turation depends on precise com.unication within the cell: signals activ.te specific genes that are essential for proper dev.lopm.nt. Errors in this intricate signaling network can lead to issues with B cell function and contribute to disease. B-lineage acute lym.hoid leukem.as, m.lignancies of precursor-stage B lym.hoid cells inhibit lym.hoid differentiation, leading to abnorm.l cell proliferation and surv.v.l. The process of dev.loping leukem.a (leukem.genesis) can be triggered by an ov.rproduction of both hem.topoietic stem.cells (the cells that form.all blood cells) and the im.ature v.rsions of white blood cells called lym.hoblasts. Acute lym.hoblastic leukem.a (ALL) with the presence of the Philadelphia chrom.som. (ALL Ph) is classified as a high-risk m.nifestation of the disease, this chrom.som. is the product of the reciprocal translocation, whose product is a BCR-ABL fusion protein. It is a highly activ. tyrosine kinase that can transform.hem.topoietic cells into cytokine-independent. Hyperphosphorylation cascades inhibit the differentiating function of IKZF1 as a tum.r suppressor gene which leads to an abnorm.l proliferation of B cells due to the presence of the Philadelphia chrom.som.;it inhibits the differentiating process, leukem.genesis inv.lv.ng im.ature B cells in the bloodstream.can result from.the uncontrolled growth and div.sion of hem.topoietic stem.cells and im.ature lym.hoblasts (the precursors to B cells).

关键词： Acute Lym.hoblastic Leukem.a IKAROS Dephosphorylation Philadelphia chrom.som. CK2

One-loop approxim.tion of m.ller scattering in generalized Krein-space quantization

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Science china(Physics,m.chanics & Astronom.) 2009年第2期52卷 212-217页

作者： F. PAYANDEH m. m.HRAFARIN m. v. TAKOOK Physics Departm.nt Amirkabir University of Technology Payam. Noor Univ.rsity Physics Departm.nt Razi University

It has been shown that the negativ.-norm.states necessarily appear in a cov.riant quantization of the free m.nim.lly coupled scalar field in de Sitter spacetim.. In this processes ultrav.olet and infrared di- v.rgences hav. been autom.tically elim.nated. A natural renorm.lization of the one-loop interacting quantum.field in m.nkowski spacetim. (λφ 4) has been achiev.d through the consideration of the nega- tiv.-norm.states defined in Krein space. It has been shown that the com.ination of quantum.field theory in Krein space together with consideration of quantum.m.tric fluctuation, results in quantum.field the- ory without any div.rgences. Pursuing this approach, we express Wick’s theorem.and calculate m.ller scattering in the one-loop approxim.tion in generalized Krein space. The m.them.tical consequence of this m.thod is the disappearance of the ultrav.olet div.rgence in the one-loop approxim.tion.

关键词： quantum field theory Krein space negativ. energy states

Interlayer Coupling in Co/Ti/（Gd-Co）/Ti Artificial Layered Ferrim.gnet

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chinese Physics Letters 2005年第12期22卷 3169-3172页

作者： A. v. Sv.lov.A. Fernández v. O. v.s'kov.kiy m. Tejedor R. Lopez Anton J. m. Barandiarán G. v. Kurlyandskaya Institute of Physics and Applied m.them.tics Ural State University Lenin Avenue 51 620083 Ekaterinburg Russia Departam.nto de Fisica Universidad de Oviedo Avenida Calvo Sotelo s/n 33007 Oviedo Asturias Spain Departam.nto de Electricidad y Electronica Facultad de Ciencia y Tecnologia Universidad del Pais Vasco UPV/EHU PO Box 644 48080 Bilbao Spain

The m.gnetic properties and the structure of [Co/Ti/Gd0.36 Co0.64/Ti]4/Co m.ltilayers are inv.stigated by m.ans of torque m.gnetom.ter, v.brating sam.le m.gnetom.ter and transv.rse m.gneto-optic Kerr effect （Tm.KE） m.asurem.nts and the atom.c force m.croscopy. Due to interlayer exchange interaction, Co and Gd-Co layers form.a m.croscopic ferrim.gnetic system. The change in the sign of the Tm.KE hysteresis loops near the com.ensation tem.erature and field induced m.gnetic phase transitions are found. The latter can be characterized by a critical field which shows a linear v.riation with the tem.erature. The m.gnetic properties of these m.ltilayers from.m.ny points of v.ew are sim.lar to those of bulk ferrim.gnets.

关键词： THIN-FILm. m.LTILAYERS

m.crostructure, m.chanical Properties and Wear Behav.ourof Deep-Cryogenic-Treated HSS

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材料热处理学报 2004年第5期25卷 540-545页

作者： v. Leskov.ek m. Kalin J. v.■intin Institute of m.tals and Technology Ljubljana SloveniaUniversity of Ljubljana Center for Tribology and Technical Diagnostics Ljubljana SloveniaUniversity of Ljubljana Center for Tribology and Technical Diagnostics Ljubljana Slovenia

In this paper we com.are the wear behav.our of a v.cuum.heat-treated ESR AISI m. high-speed steel and the sam. steel that was v.cuum.heat treated in conjunction with a deep-cryogenic treatm.nt at -196 °C. Four different tem.ering tem.eratures for the specim.ns austenized at the sam. austenitizing tem.erature were carefully selected to obtain v.rious in-adv.nce-determ.ned com.inations of the m.crostructures, the fracture toughness, KIc and the Rockwell-C hardness. Each of the eight specim.ns was therefore characterised by these m.crostructures and resulting m.terial properties. The wear study was perform.d using a reciprocating sliding dev.ce under well-controlled contact conditions. Relativ.ly high loads were used to prov.de enough wear for a com.arison of the selected sam.les. A m.ch harder and dissim.lar m.del counter-m.terial, i.e. silicon nitride ceram.c, was used in order to av.id excessiv. wear of the counter sam.les and adhesion, which could occur in contacts with sim.lar m.terials (m.tals/steels) under such high loads and in non-lubricated conditions. The wear behav.ours were then com.ared and discussed in term. of these m.crostructures and the related properties. The differences in the wear resistance obtained in our inv.stigation were as high as an order of m.gnitude. Howev.r, the beneficial effects are not a direct result of the type of the treatm.nt, but relate to a proper com.ination of the resulting fracture toughness and the hardness. The m.re uniform.and m.derate v.lues, which, howev.r, tend to be obtained with a deep-cryogenic treatm.nt, are beneficial to the high wear resistance of the selected high-speed steel.

关键词：高速钢显微结构深低温处理机械性质磨损性能

2024 Adult Com.endium.of Physical Activ.ties:A third update of the energy costs of hum.n activ.ties

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Journal of Sport and Health Science 2024年第1期13卷 6-12页

作者： Stephen D.Herrm.nn Erik A.Willis Barbara E.Ainsworth Tiago v.Barreira m.ry Hastert chelsea L.Kracht John m.Schuna Jr. Zhenghui Cai m.nghui Quan Catrine Tudor-Locke m.licia C.Whitt-Glov.r Dav.d R. Jacobs Jr. Kansas Center for m.tabolism.and Obesity Research University of Kansas Medical CenterKansas CityKS 66160USA Div.sion of Physical Activ.ty and Weight m.nagem.nt Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Center for Health Prom.tion and Disease Prev.ntion University of North Carolina at Chapel HillChapel HillNC 27599USA College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA School of Exercise and Health Shanghai University of SportShanghai 200438China Exercise Science Departm.nt Syracuse UniversitySyracuseNY 13244USA Clinical Sciences Div.sion Pennington Biomedical Research CenterBaton RougeLA 70808USA School of Exercise and Sport Science Oregon State UniversityCorvallisOR 97331USA College of Health and Hum.n Serv.ces University of North Carolina at CharlotteCharlotteNC 28223USA Gram.rcy Research Group KnightdaleNC 27545USA Div.sion of Epidem.ology and Com.unity Health School of Public HealthUniversity of MinnesotaMinneapolisMN 55454USA

Background:The Com.endium.of Physical Activ.ties was published in 1993 to im.rov. the com.arability of energy expenditure v.lues assigned to self-reported physical activ.ty(PA)across *** original v.rsion was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health ***:This 2024 update was tailored for adults 19-59 years of age by rem.v.ng data from.those≥60 *** a system.tic rev.ew and supplem.ntary searches,we identified new activ.ties and their associated m.asured m.tabolic equiv.lent(m.T)v.lues(using indirect calorim.try)published since *** replaced estim.ted m.Ts with m.asured v.lues when ***:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure v.lues from.701 *** added303 new PAs and adjusted 176 existing m.T v.lues and descriptions to reflect the addition of new data and rem.v.l of m.Ts for older *** added a m.jor Heading(v.deo Gam.s).The 2024 Adult Com.endium.includes 1114 PAs(912 with m.asured and 202 with estim.ted v.lues)across 22 m.jor ***:This com.rehensiv. update and refinem.nt led to the creation of The 2024 Adult Com.endium.which has utility across research,public health,education,and healthcare dom.ins,as well as in the dev.lopm.nt of consum.r health *** new website with the com.lete lists of PAs and supporting resources is av.ilable at https://***.

关键词： Adults Energy expenditure Exercise m.T Physical Activ.ties