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Cylindrical Three-Dimensional Dust-Ion Acoustic Propagation in Plasmas

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Communications in Theoretical Physics 2018年第9期69卷 325-330页

作者： s.k.el-labany E.k.el-shewy H.N.Abd el-Razek A.A.el-Rahman Theoretical Physics Group Faculty of Science Domietta University Department of Physics Taibah University Theoretical Physics Group Faculty of Science Mansoura University Department of Physics Faculty of Science Assiut University

Wave properties of solitons in an unmagnetized four-component dusty plasma system contains isothermal distributed electrons, mobile ions, and negative-positive dusty grains have been examined. To study DIA wave properties,a reductive perturbation (RP) analysis is used. By a reductive perturbation (RP) analysis under convenient coordinate transformation, the three dimension kadomtsev-Petviashvili equation in cylindrical coordinates is obtained. The effects of dust grain charge on soliton pulse structures are studied. More specifically, solitary profile depending on the axial,radial, and polar angle coordinates with time is discussed. This investigation may be viable in plasmas of the Earth’s mesosphere.

关键词： dust plasmas 3D-CkP equation dusty-ion acoustic solitary waves isothermal electrons

Modeling of nonlinear envelope solitons in strongly coupled dusty plasmas:Instability and collision

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Chinese Physics B 2015年第3期24卷 237-247页

作者： s.k.el-labany E.F.el-shamy W.F.el-Taibany N.A.Zedan Department of Physics Faculty of ScienceDamietta University Department of Physics College of ScienceKing Khalid University Department of Physics College of Science for Girls in AbhaKing Khalid University

Modeling of instability and collision of nonlinear dust-acoustic（NDA） envelope solitons in strongly coupled dusty plasmas（sCDPs） is theoretically investigated. The sCDPs consists of strongly correlated negatively variable-charged dust grains and weakly correlated Boltzmann electrons and ions. Using the derivative expansion perturbation technique, a nonlinear schr dinger-type（NLsT） equation for describing the propagation of NDA envelope solitons is derived. Moreover,the extended Poincar′e–Lighthill–kuo（EPLk） method is employed to deduce the analytical phase shifts and the trajectories after the collision of NDA envelope solitons. In detail, the results show that both modulation instability and phase shift after collision of NDA envelope solitons will modify with the increase in the effects of the viscosity, the relaxation time, and the dust charge fluctuation. Crucially, the modeling of dust-acoustic envelope solitons collision, as reported here, is helpful for understanding the propagation of NDA envelope solitons in strongly coupled dusty plasmas.

关键词： dust acoustic wave envelopes modulational instability head-on collision polarization effects

Nucleoside modified mRNA-lipid nanoparticles as a new delivery platform for the repair of the injured spinal cord

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Neural Regeneration Research 2025年第8期20卷 2311-2312页

作者： krisztián Pajer Tamás Bellák Antal Nógrádi Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary

spinal cord injury and treatment opportunities:The adult mammalian spinal cord has a very limited capacity for spontaneous regeneration due to various intrinsic molecular and cellular *** the spinal cord neurons have the capacity to regenerate their axons,the expression of growth inhibitory factors,lack or suppression of proper guidance cues,and profound inflammatory responses do not permit successful regeneration(khyeam et al.,2021).

关键词： injured capacity modified

Indium doping effect on properties of ZnO nanoparticles synthesized by sol–gel method

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Chinese Physics B 2019年第4期28卷 342-348页

作者： s Mourad J el Ghoul k Omri k khirouni Laboratory of Physics of Materials and Nanomaterials Applied at Environment (LaPhyMNE) Faculty of Sciences in Gabes Gabes University Imam Mohammad Ibn saud Islamic University (IMsIU) College of Sciences Department of Physics

Pure ZnO and indium-doped ZnO(In–ZO) nanoparticles with concentrations of In ranging from 0 to 5% are synthesized by a sol–gel processing technique. The structural and optical properties of ZnO and In–ZO nanoparticles are characterized by different techniques. The structural study confirms the presence of hexagonal wurtzite phase and indicates the incorporation of In^(3+) ions at the Zn^(2+) sites. However, the optical study shows a high absorption in the UV range and an important reflectance in the visible range. The optical band gap of In–ZnO sample varies between 3.16 e V and 3.22 e V. The photoluminescence(PL) analysis reveals that two emission peaks appear: one is located at 381 nm corresponding to the near-band-edge(NBE) and the other is observed in the green region. The aim of this work is to study the effect of indium doping on the structural, morphological, and optical properties of ZnO nanoparticles.

关键词： In-doped ZnO nanoparticles sol–gel process structural and optical characterization

Modulational instability of a weakly relativistic ion acoustic wave in a warm plasma with nonthermal electrons

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Chinese Physics B 2003年第7期12卷 759-764页

作者： s.k.E1-labany M.s.Abdelkrim s.A.el-Warraki W.F.E1-Taibany PhysicsDepartment FacultyofScience-DamiettaMansouraUniversityDamiettaEI-GedidaEgypt

An investigation has been made of modulational instability of a nonlinear ion acoustic wave in a weakly relativis-tic warm unmagnetized nonthermal plasma whose constituents are an inertial ion fluid and nonthermally distributedelectrons. Up to the second order of the perturbation theory, a nonlinear schrodinger type (NsT) equation for thecomplex amplitude of the perturbed ion density is obtained. The coefficients of this equation show that the relativisticeffect, the finite ion temperature and the nonthermal electrons modify the condition of the modulational stability. Theassociation between the small-wavenumber limit of the NsT equation and the oscillatory solution of the korteweg-deVaries equation, obtained by a reductive perturbation theory, is satisfied.

关键词： derivative expansion method warm plasma ion acoustic waves modulational instability

Theoretical prediction of structural,electronic and optical properties of quaternary alloy Zn_(1-x)Be_xs_yse_(1-y)

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Chinese Physics B 2012年第3期21卷 321-327页

作者： Hacini k Meradji H Ghemid s el Haj Hassan F Laboratoire LPR D'epartement de PhysiqueFaculté des SciencesUniversité de Annaba Laboratoire de physique des Matériaux Faculté des SciencesUniversité Libanaise

Within density functional theory based on the full potentiM-linearized augmented plane wave method, we carry out the first-principles calculation of the structural, electronic, and optical properties of the zinc blende quaternary alloy Zn1-xBexsyse1-y. The Perdew-Burke-Ernzerhof generaized gradient approximation based on the optimization of total energy and the Engel-Vosko generalized gradient approximation based on the optimization of the corresponding potential are used. Our investigation on the effect of the composition on lattice constants, bulk modulus, band gap, optical dielectric constant, and refractive index shows a non-linear dependence. The energy gap Eg（x, y） has been determined over the entire compositions x and y. In addition, the energy band gap of the technologically important quaternary alloy Znl-xBexsyse1-y in conditions of being lattice matched to Zns substrate has been investigated. It is noteworthy that the present work is the first theoretical study of the quaternary alloy of interest.

关键词： density functional theory full potential-linearized augmented plane wave method qua-ternary alloy lattice-matched substrate

A Combined Heterotic string and kähler Manifold elucidation of Ordinary Energy,Dark Matter,Olbers’s Paradox and Pure Dark Energy Density of the Cosmos

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Journal of Modern Physics 2017年第7期8卷 1101-1118页

作者： Mohamed s.el Naschie Department of Physics Faculty of ScienceUniversity of AlexandriaAlexandriaEgypt

We utilize the topological-geometrical structure imposed by the Heterotic superstring theory on spacetime in conjunction with the k3 kähler manifold to explain the mysterious nature of dark matter and its coupling to the pure dark energy density of the cosmos. The analogous situations in the case of a kerr black hole as well as the redundant components of the Riemannian tensor are pointed out and the final result was found to be in complete agreement with all previous theoretical ones as well as all recent accurate measurements and cosmic observations. We conclude by commenting briefly on the Cantorian model of Zitterbewegung and the connection between Olbers’s paradox and dark energy.

关键词： Heterotic strings k3 kahler Manifold Dark Matter Pure Heterotic Dark Energy Einstein’s Relativity Accelerated Cosmic Expansion Negative Gravity Fractal spacetime E-Infinity Theory kerr Black Holes Geometry kaluza-klein Theory Dvoretzky’s Theorem Empty set Zero set Connes Noncommutative Geometry ‘tHooft Renormalon sTATE Vector Reduction Density Matrix ‘tHooft Fractal spacetime Transfinite Cellular Automata Interpretation of Quantum Mechanics Zitterbewegung Olbers’s Dark sky Paradox

Feasibility of new ladle-treated Hadfield steel for mining purposes

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International Journal of Minerals,Metallurgy and Materials 2018年第3期25卷 300-309页

作者： M.k. el Fawkhry Central Metallurgical Research and Development Institute (CMRDI) Box 87 Helwan Egypt

A debate has arisen over the possibility of using a new ladle-treated Hadfield steel instead of conventional heat-treated Hadfield steel in mining applications. This debate might be solved by identifying the differences between the mechanical properties and strain-hardening properties of conventional heat-treated Hadfield steel and its counterpart ladle-treated Hadfield steel. Tensile and compression tests demonstrated that the ductility of ladle-treated Hadfield steel is similar to that of conventional heat-treated steel. However, the strain-hardening property of the ladle-treated Hadfield steel is almost two times higher than that of the heat-treated Hadfield steel. The results of this study demonstrate that the improvement of the strain-hardening behavior is attributable to the low stacking-fault energy of the main austenite matrix, which results from the high segregation coefficient of carbon and manganese solutes of the main austenite matrix into the new eutectic phase. superior wear abrasion resistance is a potential consequence of different strain-hardening properties under low and high loads.

关键词： Hadfield steel ladle treatment process wear abrasion resistance strain hardening properties mechanical properties

Exact solution of space-Time Fractional Coupled EW and Coupled MEW Equations Using Modified kudryashov Method

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Communications in Theoretical Physics 2017年第7期67卷 49-56页

作者： k. R. Raslan Talaat s. el-Danaf khalid k. Ali Mathematics Department Faculty of Science Al-Azhar University Mathematics Department Faculty of science Ai-Azhar University Nasr City 11884 Cairo Egypt Faculty of Science Menoufia University Shebein E1-Koom Egypt

In the present paper, we established a traveling wave solution by using modified kudryashov method for the space-time fractional nonlinear partial differential equations. The method is used to obtain the exact solutions for different types of the space-time fractional nonlinear partial differential equations such as, the space-time fractional coupled equal width wave equation(CEWE) and the space-time fractional coupled modified equal width wave equation(CMEW), which are the important soliton equations. Both equations are reduced to ordinary differential equations by the use of fractional complex transform and properties of modified Riemann–Liouville derivative. We plot the exact solutions for these equations at different time levels.

关键词： fractional coupled EW fractional coupled MEW equations modified kudryashov method