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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 University Physics Departm.nt Razi University

It has been shown that the negative-norm.states necessarily appear in a covariant quantization of the free m.nim.lly coupled scalar field in de Sitter spacetim.. In this processes ultraviolet and infrared di- vergences have been autom.tically elim.nated. A natural renorm.lization of the one-loop interacting quantum.field in m.nkowski spacetim. (λφ 4) has been achieved through the consideration of the nega- tive-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 divergences. 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 ultraviolet divergence in the one-loop approxim.tion.

关键词： quantum field theory Krein space negative energy states

The Asym.totics of the Heat Sem.group for a General Bounded Dom.in with m.xed Boundary Conditions

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Acta m.them.tica Sinica,english Series 2000年第4期16卷 627-636页

作者： e. m. e. Zayed m.them.tics Departm.nt. Faculty of Science. Zagazig University. Zagazig. egypt

Sm.ll-tim. asym.totics of the trace of the heat sem.group θ（t）=Σv=1x exp（-tμv）. where {μv} are the eigenvalues of the uegative Laplacian -Δ= -Σβ=12（/xβ）2 in the （x1, x2）-plane. is studied for a general bounded dom.in Ω with a sm.oth boundary Ω. where a finite num.er of Dirichlet. Neum.nn and Robin boundary conditions, on the piecewise sm.oth parts Γi（i=1, ..., n） of )Ω such that)Ω=∪i=1nΓ are considered. Som. geom.trical properties associated with Ω are determ.ned

关键词： Heat sem.group Inverse problem m.xed boundary conditions eigenvalues

Seism.c assessm.nt of unanchored steel storage tanks by endurance tim. m.thod

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earthquake engineering and engineering Vibration 2011年第4期10卷 591-603页

作者： m. Alem.agheri H.e. estekanchi Departm.nt of Civil engineering Sharif University of Technology (SUT)

Liquid storage tanks are essential structures that are often located in residential and industrial areas; thus an assessm.nt of their seism.c perform.nce is an im.ortant engineering issue. In this paper, the seism.c response ofunanchored steel liquid storage tanks is investigated using the endurance tim. （eT） dynam.c analysis procedure and com.ared to responses obtained for anchored tanks under actual ground m.tions and intensifying eT records. In m.st cases, the results from.ground m.tions are properly obtained with negligible differences using eT records. It is observed that uplifting of the tank base, which is closely related to the tank aspect ratio, has the greatest significance in the responses of the tank and can be predicted with reasonable accuracy by using currently available eT records.

关键词： steel liquid storage tanks endurance tim. m.thod seism.c assessm.nt intensifying dynam.c excitation tank base uplifting

Structural, elastic and electronic properties for m.2 XC (m.Ti and Cr, X=Ga and Al) phases from.ab initio calculations

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Acta m.tallurgica Sinica(english Letters) 2011年第4期24卷 255-270页

作者： B. Ghebouli m.A. Ghebouli m. Fatm. N. Bouarissa m. Benkerri I.A. Ibrahim Laboratory of Study of Surfaces and Interfaces of Solids m.terials Department of Physics Faculty of Science University of Setif Departm.nt of Physics University Center Research Unit on em.rging m.terials Ferhat Abbas University of Setif Departm.nt of Physics Faculty of Sciences King Khalid University Central m.tallurgical Research and Developm.nt Institute P.O. Box: 87 Helwan 11424 Cairo Egypt

The first-principles study of the structural, elastic and electronic properties of the m.XC phases depending on the type of m.transition m.tal （m.are Ti and Cr） and on X （X are Ga and A1） was reported. The calculations are perform.d using the pseudo-potential plane-wave approach in both the local density and generalized gradient approxim.tions. The elastic constants are calculated using the static finite strain technique. Features such as structural and elastic param.ters, Debye tem. perature, sound velocities and their pressure dependence have been investigated. In agreem.nt with experim.ntal and previous theoretical findings, it is found that the com.ressibility along a and c axis depends on the valence electron concentration （VeC）. Correlations revealing the governing role of the X and m.elem.nts on the m.chinability indices of the m.terial have been exam.ned. The electronic properties have been discussed in term. of chem.cal bonding showing that bonding is due to m.-Cp and m.-Xp hybridizations. m.C bonds are stiffer than m.X ones and A1-Ti （Cr-C） bonds are stiffer than those corresponding to Ti-C （A1-Cr）. It is shown that the stiffness of the m.X and m.C bonds increases with increasing the num.er of VeC.

关键词： m.XC phases ab initio Pressure effect Band structures

Nonlinear forced vibration in a subcritical regim. of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied m.them.tics and m.chanics(english edition) 2025年第1期46卷 101-122页

作者： m.GHOLAm. m.eFTeKHARI Departm.nt of m.chanical engineering Shahid Bahonar University of Kerman

This study exam.nes the nonlinear behaviors of a clam.ed-clam.ed porous pipe m.de of a functionally graded m.terial(FGm. that conveys fluids and is equipped with a retaining clip, focusing on prim.ry resonance and subcritical dynam.cs. The nonlinear governing equations for the FGm.pipe are derived by the extended Ham.lton's principle, and subsequently discretized through the application of the Galerkin *** direct m.thod of m.lti-scales is then used to solve the derived equations. A thorough analysis of various param.ters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a com.rehensive understanding of the system.s nonlinear dynam.cs. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the com.arisons with m.tallic pipes em.hasize the role of FGm.com.osition. The exam.nation of the forced response curves reveals saddle-node bifurcations and their dependence on param.ters such as the detuning param.ter and the power-law index, offering valuable insights into the system.s nonlinear resonant behavior. Furtherm.re, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system.response and resonance characteristics. This com.rehensive analysis enhances the understanding of nonlinear behaviors in FGm.porous pipes with a retaining clip, providing key insights for practical engineering applications in system.design and optim.zation.

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The sexually dim.rphic expression of glutam.te transporters and their im.lication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer m.Colón-m.rcado Aranza I.Torrado-Tapias Iris K.Salgado Jose m.Santiago Sam.el e.Ocasio Rivera Dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge D.m.randa Departm.nt of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of m.tor function,~60% of patients develop pain after spinal cord *** cellular-m.lecular m.chanism. are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penum.ra of the injury site initiates a cellularm.lecular interplay that acts as a rewiring m.chanism.leading to central neuropathic *** can lead to the form.tion of new connections triggering abnorm.l sensory *** excitatory glutam.te transporters are responsible for the reuptake of extracellular glutam.te which m.kes them.a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dim.rphic therapeutic window for spinal cord injury after treatm.nt with the selective estrogen receptor m.dulator *** this study,we investigated the anti-allodynic effects of tam.xifen in m.le and fem.le rats with spinal cord *** hypothesized that tam.xifen exerts anti-allodynic effects by increasing the expression of glutam.te transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and fem.le rats received a m.derate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatm.nt of tam.xifen or m.trix pellets as a control(placebo).We used von Frey m.nofilam.nts and the“up-down m.thod”to evaluate m.chanical *** treatm.nt decreased allodynia only in fem.le rats with spinal cord injury revealing a sexdependent *** expression profile of glutam.tergic transporters(excitatory am.no acid transporter 1/glutam.te aspartate transporter and excitatory am.no acid transporter 2/glutam.te transporter-1)revealed a sexual dim.rphism.in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression prim.rily on *** rodents showed a significantly higher level of excitatory am.no acid transporter-1 expression while m.le rodents showed increased

关键词： allodynia central neuropathic pain eAAT-1/GLAST eAAT-2/GLT-1 glutam.te transporters selective estrogen receptor m.dulator sexual dim.rphism spinal cord injury traum.

m.asurem.nt of the pion form.factor for m.(ππ)～2 between 0.1 and 0.85 GeV^2 with the KLOe detector

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Chinese Physics C 2010年第6期34卷 686-691页

作者： Stefan e.m.ller Institut für Kernphysik Johannes Gutenberg-Universitt

The KLOe experim.nt at the φ-factory DAФPNe has m.asured the pion form.factor in the range between 0.1 〈 m.π^2 〈 0.85 GeV^2 using events taken at √s = 1 GeV with a photon em.tted at large polar angles in the initial state. This m.asurem.nt extends the m.π^2 region covered by KLOe ISR m.asurem.nts of the pion form.factor down to the two pion production threshold. The value obtained in this m.asurem.nt of the dipion contribution to the m.on anom.lous m.gnetic m.m.nt of △αμ^ππ= （478.5±2-0stat±4.8syst±2.9theo）·10^-10 further confirm. the discrepancy between the Standard m.del evaluation for αμ and the experim.ntal value m.asured by the （g-2） collaboration at BNL.

关键词： hadronic cross section initial state radiation pion form.factor m.on anom.ly

On the solutions and periodic nature of som. system. of difference equations

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International Journal of Biom.them.tics 2014年第6期7卷 121-146页

作者： e. m. elsayed m.them.tics Departm.nt Faculty of ScienceKing Abdulaziz University P. O. Box 80203 Jeddah 21589 Saudi Arabia Departm.nt of m.them.tics Faculty of ScienceMansoura University Mansoura 35516 Egypt

In this paper, we consider the solution of the following rational system. of difference equations：xn＋1=zn-1xn-2/xn-2±yn,yn＋1=xn-1yn-2/yn-2±zn,zn＋1=yn-1zn-2/zn-1±xn,where initial conditions are nonzero real num.... 详细信息

关键词： Difference equations recursive sequences periodic solutions system.of differ-ence equations stability.

m.nte Carlo sim.lation of lattice analysis of com.lex LaCeTh0.1CuOy using ion bom.ardm.nt technique

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Nuclear Science and Techniques 2020年第3期31卷 20-34页

作者： m.e.em.tere Departm.nt of Physics Covenant University Canaanland Departm.nt of m.chanical engineering Science University of Johannesburg

Ion bom.ardm.nt analysis of perovskite m.terials is challenging owing to their peculiar *** shortcom.ng renders the reliability on the technique som.what *** this research,three structured m.difications(i.e.,scan angle,low energy,and large ion bom.ardm.nt)were adopted to im.rove the ion bom.ardm.nt analysis of 99,999 ions using m.nte Carlo *** m.dified technique was used to analyze the effects of a chem.cally pressurized‘‘A’’site in the perovskite lattice *** LaCeTh0.1Cu2Oy com.ound was used in this *** the low probing energy,it was observed that the high num.er of ions bom.arding the m.terial resulted in external pressure on the lattice structure of the ***,the chem.cally pressurized‘‘A’’site perovskite m.terial was characterized by lattice m.sm.tch,lattice fluctuations,grain boundary collapse,and oxygen *** novel discovery of this research is the inter-and intra-extended lattice m.sm.tches that are likely to ***,further investigation of the connection between inter-and intraextended lattice m.sm.tches is recom.ended as they m.y enable fabrication of room.tem.erature superconductors.

关键词： Lattice m.sm.tch Ion bom.ardm.nt Chem.cal pressure Scan angle