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Surface plasm.n oscillations in a sem.-bounded sem.conductor plasm.

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Plasm. Science and Technology 2018年第2期20卷 76-81页

作者： m.shahmansouri A P m.SRA Departm.nt of Physics Faculty of ScienceArak University Departm.nt of m.them.tics Siksha BhavanaVisva-Bharati University

We study the dispersion properties of surface plasm.n（SP） oscillations in a sem.-bounded sem.conductor plasm. with the effects of the Coulom. exchange（CE） force associated with the spin polarization of electrons and holes as well as the effects of the Ferm. degenerate pressure and the quantum.Bohm.*** from.a quantum.hydrodynam.c m.del coupled to the Poisson equation,we derive the general dispersion relation for surface plasm. *** results in this context are *** dispersion properties of the surface waves are analyzed in som. particular cases of interest and the relative influence of the quantum.forces on these waves are also studied for a nano-sized Ga As sem.conductor *** is found that the CE effects significantly m.dify the behaviors of the SP *** present results are applicable to understand the propagation characteristics of surface waves in solid density plasm.s.

关键词： surface plasm.n oscillations sem.conductor plasm. sem.-bounded plasm.

On the dielectric response function and dispersion relation in strongly coupled m.gnetized dusty plasm.s

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Chinese Physics B 2018年第10期27卷 465-470页

作者： m.shahmansouri N Khodabakhshi Departm.nt of Physics Faculty of ScienceArak University

Using the generalized viscoelastic fluid m.del, we derive the dielectric response function in a strongly coupled dusty m.gnetoplasm. which reveals two different dust acoustic（DA） wave m.des in the hydrodynam.c and kinetic lim.ts. The effects of the strong interaction of dust grains and the external m.gnetic on these DA m.des, as well as on the shear wave are exam.ned. It is found that both the real and im.ginary parts of DA waves are significantly m.dified in strongly coupled dusty m.gnetoplasm.s. The im.lications of our results to space and laboratory dusty plasm.s are briefly discussed.

关键词： dusty plasm. strongly coupled plasm. m.gnetoplasm. dielectric response function

m.lti-ion Double Layers in a m.gnetized Plasm.

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Com.unications in Theoretical Physics 2015年第11期64卷 555-564页

作者： m.shahmansouri H.Alinejad m.Tribeche Departm.nt of Physics Faculty of ScienceArak University Departm.nt of Physics Faculty of Basic ScienceBabol University of Technology Faculty of Physics Theoretical Physics LaboratoryPlasma Physics GroupUniversity of Bab-EzzouarUSTHB

A theoretical investigation is carried out to study the existence,form.tion and basic properties of ion acoustic(IA) double layers(DLs) in a m.gnetized bi-ion plasm. consisting of warm.cold ions and Boltzm.nn distributed *** on the reductive perturbation technique,an extended Korteweg de-Vries(KdV) equation is *** propagation of two possible m.des(fast and slow),and their evolution are *** effects of obhqueness,m.gnitude of the m.gnetic field,ion concentration,polarity of ions,and ion tem.erature on the IA DL profile are analyzed,and then the ranges of param.ters for which the IA DLs exist are investigated in details.

关键词： ion acoustic waves bi-ion plasm. double-layers

Large Am.litude Dust Ion Acoustic Solitons and Double Layers in Dusty Plasm.s with Ion Stream.ng and High-Energy Tail Electron Distribution

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Com.unications in Theoretical Physics 2014年第3期61卷 377-384页

作者： m.hran shahmansouri m.uloud Tribeche Departm.nt of Physics Faculty of Science Arak University Faculty of Sciences Theoretical Physics Laboratory Plasma Physics Group University of Bab-Ezzouar

Large am.litude dust ion acoustic （DIA） solitons as well as double layers （DLs） are studied in a dusty plasm. having a high-energy-tail electron distribution. The influence of electron deviation from.the m.xwellian distribution and ion stream.ng on the existence dom.in of solitons is discussed in the （m. f） space using the pseudo-potential approach. It is found that in the presence of stream.ng ions and for a fixed f, solitons m.y appear for larger values of m. This m.ans that in the presence of ion stream.ng, high values of the m.ch num.er are needed to have soliton. The DIA solitary waves profile is highly sensitive to the ion stream.ng speed. Their am.litude is found to decrease with an increase of the ion stream.ng speed. In addition, we find that the ion stream.ng effect m.y lead to the appearance of double layers. The results of this axticle should be useful in understanding the basic nonlinear features of DIA waves propagating in space dusty plasm.s, especially those including a relative m.tion between species, such as com.t tails and solar wind stream., etc.

关键词： dust ion acoustic solitons double layers supertherm.l electrons dusty plasm. stream.ng ions

Polarized Debye Sheath in Degenerate Plasm.s

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Com.unications in Theoretical Physics 2019年第11期71卷 1341-1345页

作者： m.shahmansouri A.P.m.sra Departm.nt of Physics Faculty of ScienceArak UniversityArakP.O.Box 38156-8-8349Iran Departm.nt of m.them.tics Siksha BhavanaVisva-Bharati(A Central University)Santiniketan-731235India

The force on a charged dust grain in a plasm. due to polarization of therm.l ions and degenerate electrons around the grain is derived in the lim.ts of weakly relativistic and ultra-relativistic degeneracy of electrons. It is found that in both these cases, the m.gnitude of the polarization force is enhanced com.ared to that in classical plasm.s. The influence of this force on dust-acoustic(DA) m.des is exam.ned and discussed. It is shown that the DA wave frequency in degenerate plasm.s is significantly reduced com.ared to the classical DA m.de.

关键词： degenerate plasm. polarization force dust acoustic waves

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

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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Neurogenesis dynam.cs in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： m.awiah m.Naffaa Departm.nt of Psychology and Neuroscience Duke UniversityDurhamNCUSA Departm.nt of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons m.grating to the granule cell layer and glom.rular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit rem.deling triggered by m.m.ry and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. m.reover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory inform.tion processing. This adaptive process responds to changes in epithelial com.osition and contributes to the form.tion of olfactory m.m.ries by m.dulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions rem.ins a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around m.tral and tufted cells. This organizational pattern significantly im.acts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and m.m.ry. Additionally, this organization is further shaped by axon term.nals originating from.cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these com.lex and highly interconnected processes have not been com.rehensively studied as a whole. Therefore, this m.nuscript aim. to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These m.chanism. are thought to support olfactory learning and m.m.ry, potentially through increased

关键词： network adaptability neurogenesis neuronal com.unication olfactory bulb olfactory learning olfactory m.m.ry synaptic plasticity