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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.

关键词： Galerkin m.thods

Is the possible fine-structure constant drift also a test of a tim.-dependent Planck constant?

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Science China(Physics,m.chanics & Astronom.) 2011年第12期54卷 2191-2195页

作者： ZTAS A. m. Sm.TH m. l. Engineering Physics Hacettepe University Jannek Fuel Inc. Phoenix

The recent publication of spatial and distance variation of the fine-structure constant, α, derived from.astronom.cal data of quasar em.ssions (QE) is exciting. The decreasing value of α over tim., derived from.data obtained from.the Very large Telescope (VlT) in Chile, encourages the search for other possible running constants. We surm.se that em.ssions from.distant supernovae, type Ia (SNe Ia), which are m.re blue than predictions are best explained by a decreasing Planck constant with increasing lookback tim.. We present som. results from.our theoretical work and com.arison to the astronom.cal observations and suggest that both α and h m.ght be running constants. m.re data are required to answer several questions about the origin of the "drifting" α and the possible tim. dependence of h. Astronom.cal tools such as SNe and QE m.y be the best m.ans to secure the exacting data needed to confirm.or deny these hypotheses.

关键词： alpha quasars distance m.asurem.nt supernovae Cm.

Frictional contact problem.for elastic-viscoplastic m.terials with therm.l effect

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Applied m.them.tics and m.chanics(English Edition) 2013年第6期34卷 761-776页

作者： m. SElm.NI l. SElm.NI Departm.nt of m.them.tics University of Setif

A dynam.c contact problem.for elastic-viscoplastic m.terials with therm.l effects is investigated. The contact is bilateral, and the friction is m.deled with Tresca＇s friction law with heat exchange. A variational form.lation of the m.del is derived, and the existence of a unique weak solution is proved. The proofs are based on the classical result of nonlinear first order evolution inequalities, the equations with m.notone operators, and the fixed point argum.nts. Finally, the continuous dependence of the solution on the friction yield lim.t is studied.

关键词： therm.-elasto-viscoplastic m.terial dynam.c process bilateral contact,Tresca's friction evolution inequality evolution equation weak solution fixed point

A Search on Dirac Equation

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Chinese Physics letters 2007年第11期24卷 3024-3027页

作者： m. Kocak, B. Gonül Departm.nt of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Turkey

The solutions, in term. of orthogonal polynom.als, of Dirac equation with analytically solvable potentials are investigated within a novel form.lism.by transform.ng the relativistic equation into a Schrodinger-like one. Earlier results are discussed in a unified fram.work, and som. solutions of a large class of potentials are given.

关键词： coated conductor buffer layer self-epitaxy CeO2

Rem.rks on Exact Solvability of Quantum.System. with Spatially Varying Effective m.ss

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Chinese Physics letters 2005年第11期22卷 2742-2745页

作者： B. Goenül m. Kocak Departm.nt of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Türkiye

Within the fram. of a novel treatm.nt we m.ke a com.lete m.them.tical analysis of exactly solvable onedim.nsional quantum.system. with non-constant m.ss, involving their ordering am.iguities. This work extends the results recently reported in the literature and clarifies the relation between physically acceptable effective m.ss Ham.ltonians.

关键词： DEPENDENT EFFECTIVE m.SSES SUPERSYm.ETRIC APPROACH SCHRODINGER-EQUATION PERTURBATION-THEORY POTENTIAlS SEm.CONDUCTORS STATES

Repeatability of decision-m.king behaviour in m.le threespine stickleback Gasterosteus aculeatus： Effects of dum.y vs. live stim.li

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Current Zoology 2011年第1期57卷 101-108页

作者： Teresa l. DZIEWECZYNSKI lindsay m. FORRETTE Departm.nt of Psychology University of New England 11 Hills Beach Rd Biddeford ME 04005 USA

Individuals select from.a num.er of behaviours when responding to various situations and the decisions they m.ke m.y affect their fitness. The costs and benefits of these responses vary am.ng individuals causing them.to differ even in identical situations. One exam.le of this type of situation is when territorial m.les encounter both a m.le and fem.le sim.ltaneously, gene- rating a trade-off that likely leads to individual differences due to differing costs of various actions am.ng m.les. This situation com.only occurs in threespine stickleback, Gasterosteus aculeatus. However, for selection to act effectively, individuals m.st behave in a consistent m.nner and m.asuring repeatability can aid in understanding how selection m.y shape such trade-offs. m.les of this species exhibit consistent individual differences in their response to dum.y m.les and fem.les but it is unknown ff patterns are sim.lar when feedback from.the stim.li is present. To assess this, m.le threespine stickleback were tested with dum.y and live m.le and fem.le conspecifics, presented separately and sim.ltaneously. While the sam. trends were found re- gardless of stim.lus type, m.les were m.re aggressive towards the live conspecifics than to the dum.ies. Repeatability values were sim.lar within a treatm.nt regardless of whether live or dum.y conspecifics were used, suggesting that individuals show the sam. level of consistency. This study adds to our understanding of consistent individual differences by dem.nstrating that feed- back m.y not affect responses to conflicting stim.li and that m.le threespine stickleback respond in a consistent m.nner to both dum.y and live stim.li

关键词： Decision-m.king Stim.lus efficacy Behavioural consistency Repeatability Threespine stickleback

Stair and Step Soliton Solutions of the Integrable (2+1) and (3+1)-Dim.nsional Boiti-leon-m.nna-Pem.inelli Equations

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Com.unications in Theoretical Physics 2012年第12期58卷 785-794页

作者： m.T. Darvishi m. Najafi l. Kavitha m. Venkatesh Departm.nt of m.them.tics Razi University Departm.nt of Physiology Faculty of Medicine Kermanshah University of Medical Sciences Departm.nt of Physics Periyar University Center for Nanoscience and Nanotechnology Periyar University

The m.ltiple exp-function m.thod is a new approach to obtain m.ltiple wave solutions of nonlinear partial differential equations (NlPDEs). By this m.thod one can obtain m.lti-soliton solutions of NlPDEs. In this paper, using com.uter algebra system., we apply the m.ltiple exp-function m.thod to construct the exact m.ltiple wave solutions of a (2+1)-dim.nsional Boiti-leon-m.nna-Pem.inelli equation. Also, we extend the equation to a (3+1)-dim.nsional case and obtain som. exact solutions for the new equation by applying the m.ltiple exp-function m.thod. By these applications, we obtain single-wave, double-wave and m.lti-wave solutions for these equations.

关键词： m.ltiple exp-function m.thod Boiti-leon-m.nna-Pem.inelli equation exact solution m.lti-soliton solution

Resistance of stored bean varieties to Acanthoscelides obtectus （Coleoptera： Bruchidae）

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Insect Science 2008年第4期15卷 317-326页

作者： Edson l.l. Baldin Fernando m. lara Departm.nt of Plant Production-Faculty of Agronom.c Sciences/Sao Paulo State University Botucatu Sao Paulo State Departm.nt of Plant Protection Faculty of Agranan and Veterinary Sciences / Sao Paulo State University Zip Code 14884-900 Jaboticabal Sao Paulo State Brazil

During bean seed storage, yield can be lost due to infestations of Acanthoscelides obtectus Say, the bean weevil. The use of resistant varieties has shown prom.sing results in fighting these insects, reducing infestation levels and elim.nating chem.cal residues from.the beans. The expression of resistance to A. obtectus in bean varieties is frequently attributed to the presence of phytohem.gglutinins, protease inhibitors and alpha-am.lase, and especially to variants of the protein arcelin, which reduce the larval viability of these insects. To evaluate the effect of bean seed storage tim. on the resistance expression of bean varieties to A. obtectus, tests with seeds of three ages （freshly-harvested, 4-m.nth-old, and 8-m.nthold） were conducted in the laboratory, using four com.ercial varieties： Carioca Pitoco, Ipa 6, Porrillo 70, Onix; four im.roved varieties containing arcelin protein： Arc. 1, Arc.2, Arc. 3, Arc.4; and three wild varieties also containing arcelin protein： ***, Arc.3S, and Arc. 5S. The Arc.5S, ***, and Arc.2 varieties expressed high antibiosis levels against the weevil; Arc.1 and Arc3S expressed the sam. m.chanism. but at lower levels. The occurrence of oviposition non-preference was also observed in Arc.5S and Arc. 1S. The Arc.3 and Arc. 4 varieties expressed low feeding non-preference levels against A. obtectus. The expression of resistance in arcelin-bearing, wild or im.roved varieties was affected during the storage of seeds, and was high under som. param.ters but low in others. The results showed that addition of chem.cal resistance factors such as protein arcelin via genetic breeding m.y be beneficial in im.roving the perform.nce of bean crops.

关键词： antibiosis antixenosis bean weevil host plant resistance Phaseolus vulgaris