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Acta mathematica Sinica,English Series 1995年第4期11卷 399-407页

作者： E. m. E. zayed S. F. m. Ibrahim mathematics Department Faculty of Science Zagazig University Zagazig Egypt mathematics Department Faculty of Science Ain Shams University Heliopolis Cairo Egypt

The object of this paper is to establish an expansion theorem for a regular right- definite eigenvalue problem with an eigenvalue parameter λ which is contained in the Schrodinger partial differential,equation and in a general type of boundary conditions on the boundary of an arbitrary multiply connected bounded domain in R^n(n≥2).We associate with this problem an essentially self-adjoint operator in a suitably defined Hilbert space and then we develop an associated eigenfunction expansion theorem.

关键词： Eigenvalue problem multiply connected domain Eigenfunction expansion

Inequalities and Separation for a Biharmonic Laplace-Beltrami Differential Operator in a Hilbert Space Associated with the Existence and Uniqueness Theorem

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Journal of Partial Differential Equations 2016年第1期29卷 59-70页

作者： zayed E. m. E. Department of mathematics Faculty of Science Zagazig University P.O. Box 44519 Zagazig Egypt.

In this paper, we have studied the separation for the biharmonic Laplace-Beltrami differential operatorAu（x） = -△△u（x）＋ V（x）u（x）,for all x ∈ R^n, in the Hilbert space H = L2（R^n,H1） with the operator potential V（x） ∈ C^1 （R^n, L （H1））, where L （H1 ） is the space of all bounded linear operators on the Hilbert space H1, while AAu is the biharmonic differential operator and△u=-∑i,j=1^n 1/√detg δ/δxi[√detgg-1（x）δu/δxj]is the Laplace-Beltrami differential operator in R^n. Here g（x） = （gij（x）） is the Riemannian matrix, while g^-1 （x） is the inverse of the matrix g（x）. moreover, we have studied the existence and uniqueness Theorem for the solution of the non-homogeneous biharmonic Laplace-Beltrami differential equation Au = - △△u ＋ V（x） u （x） = f（x） in the Hilbert space H where f（x） ∈ H as an application of the separation approach.

关键词： Separation biharmonic Laplace-Beltrami operator operator potential Hilbert space L2 (R^n, H1) coercive estimate existence and uniqueness Theorem.

The Riccati Equation method Combined with the Generalized Extended(G'/G)-Expansion method for Solving the Nonlinear KPP Equation

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Journal of mathematical Research with Applications 2017年第5期37卷 577-590页

作者： E.m.E.zayed Abdul-Ghani AL-NOWEHY Department of mathematics Faculty of Sciences Zagazig University Department of mathematics Faculty of Education and Science Taiz University

An analytic study of the nonlinear Kolmogorov-Petrovskii-Piskunov(KPP) equation is presented in this paper. The Riccati equation method combined with the generalized extended(G’/G)-expansion method is an interesting approach to find more general exact solutions of the nonlinear evolution equations in mathematical physics. We obtain the traveling wave solutions involving parameters, which are expressed by the hyperbolic and trigonometric function solutions. When the parameters are taken as special values, the solitary and periodic wave solutions are given. Comparison of our new results in this paper with the well-known results are given.

关键词： the generalized extended(G’/G)-expansion method the Riccati equation method the nonlinear KPP equation exact solutions solitary wave solutions periodic wave solutions

magnetron sputtered Dy2O3 with chromium and copper contents for antireflective thin films with enhanced absorption

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Journal of Rare Earths 2019年第9期37卷 989-994,I0004页

作者： Shahid m. Ramay Asif mahmood Hamid m. Ghaithan Nasser S. Al-zayed Adnan Aslam Abdullah murtaza Nisar Ahmad Saadat A. Siddiqi murtaza Saleem Physics and Astronomy Department College of ScienceKing Saud University RiyadhSaudi Arabia Chemical Engineering Department College of EngineeringKing Saud University RiyadhSaudi Arabia Department of Physics The University of Lahore1-KM Raiwind RoadLahore. Pakistan Interdisciplinary Research Centre in Biomedical materials COMSATS Institute of Information TechnologyDefence RoadOff Raiwind RoadLahore Pukiston Department of Physics SBASSELahore University of Management Sciences (LUMS)Lahore 4792Pakisran

Dy2O3 is a rare earth oxide having a number of advanced applications in various fields including protective or antireflective coatings,main objective of this novel research work is to check the effect of Cr and Cu addition on different properties of Dy2O3 and achievement of antireflective thin films with enhanced abso *** films of these materials we re deposited using DC magnetron with reactive *** studies reveals the crystalline nature of thin films having Dy2O3(222)reflection in all samples with Cr2O3(116)and CuO(111)reflections in Cr and Cu containing *** emission scanning electron microscopy demonstrates the homogeneous deposition of thin films with uniform shape,size and distribution of *** index,extinction coefficient and absorption coefficient significantly increase while optical reflectance decreases with Cr and Cu mediation corroborating an improved antireflective *** imaginary part of dielectric constant is found to increase slightly with low tangent loss for Cr containing composition co nsidered favorable for energy storage applications.

关键词： Thin films Dysprosium oxide X-ray diffraction FESEm Optical properties Anti-reflective

Solitons and Other Solutions for the Generalized KdV-mKdV Equation with Higher-order Nonlinear Terms

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Journal of Partial Differential Equations 2016年第3期29卷 218-245页

作者： zayed Elsayd m. E. AL-NOWEHY Abdul-Ghani Department of mathematics Faculty of Sciences Zagazig University ZagazigEgypt. Department of mathematics Faculty of Education and Science Taiz UniversityTaiz Yemen.

The generalized sub-ODE method, the rational （G＇/G）-expansion method, the exp-function method and the sine-cosine method are applied for constructing many traveling wave solutions of nonlinear partial differential equations （PDEs）. Some illustrative equations are investigated by these methods and many hyperbolic, trigonometric and rational function solutions are found. We apply these methods to obtain the exact solutions for the generalized KdV-mKdV （GKdV-mKdV） equation with higherorder nonlinear terms. The obtained results confirm that the proposed methods are efficient techniques for analytic treatment of a wide variety of nonlinear partial differential equations in mathematical physics. We compare between the results yielding from these methods. Also, a comparison between our new results in this paper and the well-known results are given.

关键词： Generalized sub-ODE method rational (G'/G)-expansion method exp-functionmethod sine-cosine method generalized KdV-mKdV equation with higher-order nonlinear terms exact solutions solitary wave solutions.

Rare earth based mgPm_(2)X_(4)(X=S,Se) spinel chalcogenides for spintronic and thermoelectric applications

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Journal of Rare Earths 2024年第8期42卷 1577-1585,I0006页

作者： Tariq m.Al-Daraghmeh Omar zayed Ghulam m.mustafa Taharh Zelai Bisma Younas Hind Albalawi S.Bouzgarrou Othman Hakami Q.mahmood Khaild I.Hussein Basic Sciences Department King Abdullah Ⅱ School of EngineeringPrincess Sumaya University For TechnologyP.O.Box 1438Al-jubaiha11941AmmanJordan Department of Physics Division of Science&TechnologyUniversity of EducationLahorePakistan Department of Physics Faculty of ScienceJazan University JazanSaudi Arabia Department of Physics The University of LahoreLahorePakistan Department of Physics College of SciencesPrincess Nourah bint Abdulrahman University(PNU)P.O.Box 84428Riyadh11671Saudi Arabia Department of Physics College of ScienceQassim UniversityPo.64BuraidahSaudi Arabia Laboratoire de microelectronique et Instrumentation(UR 03/13-04) Faculte des Sciences de MonastirAvenue de I'Environnement 5000MonastirTunisia Department of Chemistry Faculty of ScienceJazan University JazanSaudi Arabia Basic&Applied Scientific Research Center Department of PhysicsCollege of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam 31441Saudi Arabia Department of Radiological Sciences College of Applied Medical SciencesKing Khalid UniversityAbha61421Saudi Arabia

In current report,the structural,magnetic,and thermoelectric properties of RE doped mgPm_(2)X_(4)(X=S,Se) spinels were *** energy difference in ferromagnetic and antiferromagnetic states reveals the stability of mgPm_(2)(S/Se)_(4) in the ferromagnetic *** co mputation of enthalpy of formation also ascertains thermodynamic stability of crystal ***-dependent band structure and density of states analysis reveal ferromagnetic semiconducting character showing different electronic behavior in both spin *** room temperature ferromagnetism,spin polarization and Curie temperature are estimated from exchange energies *** addition,exchange constants(N_(0)α and N_(0)β),exchange energy Δ_(x)(pd),crystal ifeld energy,and double exchange mechanism were studied to explore the magnetic ***,the electrical conductivity,thermal conductivity,Seebeck co-efficient,and power factor show effect on electrons spin and their potential for thermoelectric devices.

关键词： Rare earth elements Spintronic applications Thermoelectric effects Exchange energies

Fekete-Szeg Problems for Certain Classes of meromorphic Functions Using q-Derivative Operator

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Journal of mathematical Research with Applications 2018年第3期38卷 236-246页

作者： Huo TANG H.m.zayed A.O.mOSTAFA m.K.AOUF School of mathematics and Statistics Chifeng University Department of mathematics Faculty of Science Menofia University Department of mathematics Faculty of Science Mansoura University

In this paper, we introduce two subclasses Σ*q(φ) and Σ*q,α(φ) of meromorphic functions f(z) for whichqz Dq f(z)f(z)? φ(z) and

关键词： analytic function meromorphic function Fekete-Szeg problem q-derivative operator q-Bessel function

源自天然席夫碱的过渡金属配合物在分光光度法测天然水中的Fe(Ⅲ)的应用(英文)

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无机化学学报 2012年第7期28卷 1495-1505页

作者： Khalil m m H mohamed G G Ismail E H zayed m E Kamel B A 艾因·夏姆斯大学理学院化学系埃及开罗11566 开罗大学理学院化学系埃及吉萨12613 国家研究中心 Dokki埃及吉萨12613

描述了一种新颖、简便的合成含五齿配位基的大环席夫碱配体的方法,制备和表征了该席夫碱的1∶1包合物。用化学和光谱学方法测定了标题配合物的组成,认为在所有配合物中配位金属原子取八面体结构。数据表明:配体起O2N4六齿结构而每个环... 详细信息

描述了一种新颖、简便的合成含五齿配位基的大环席夫碱配体的方法,制备和表征了该席夫碱的1∶1包合物。用化学和光谱学方法测定了标题配合物的组成,认为在所有配合物中配位金属原子取八面体结构。数据表明:配体起O2N4六齿结构而每个环绕金属原子在八面体环境中。配合物的红外和1H NmR光谱符合中心金属原子的配位结果。用分光光度法测定了配合物的稳定常数。用共轭余量法(CR method)计算了在热分解的不同阶段配合物活化的动力学和热力学参数。此外,用抑菌圈直径法筛选了配体及其金属配合物抑制细菌和真菌的能力。用回收率试验研究了天然螯合配体在不同天然水体中对Fe(Ⅲ)离子配合作用的影响。

关键词：席夫碱配合物光谱学技术生物活性回收率

Exact Traveling Wave Solutions for Higher Order Nonlinear Schrodinger Equations in Optics by Using the （G＇/G,1/G）-expansion method

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Journal of Partial Differential Equations 2015年第4期28卷 332-357页

作者： zayed E. m. E. ALURRFI K. A. E. Department of mathematics Faculty of Science Zagazig University P. O. Box 44519Zagazig Egypt

The propagation of the optical solitons is usually governed by the nonlinear Schrodinger equations. In this article, the two variable （G＇/G,1/G）-expansion method is employed to construct exact traveling wave solutions with parameters of two higher order nonlinear Schrodinger equations describing the propagation of femtosecond pulses in nonlinear optical fibers. When the parameters are replaced by special values, the well-known solitary wave solutions of these equations rediscovered from the traveling waves. This method can be thought of as the generalization of well-known original （G＇/G）-expansion method proposed by m. Wang et al. It is shown that the two variable （G＇/G,1/G）-expansion method provides a more powerful mathematical tool for solving many other nonlinear PDEs in mathematical physics.

关键词： The two variable (G'/G,1/G)-expansion method Schrodinger equations exact traveling wave solutions Solitary wave solutions.

THE WAVE EQUATION APPROACH TO THE TWO-DImENSIONAL INVERSE PROBLEm FOR A GENERAL BOUNDED DOmAIN WITH PIECEWISE SmOOTH mIXED BOUNDARY CONDITIONS

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Acta mathematica Scientia 2001年第2期21卷 171-181页

作者： E.m.E.zayed, I.H.Abdel-Halim mathematics Department, Faculty of Science, Zagazig University, Zagazig, Egypt E-mail: emezayed@*** & ismhalim@*** Zagazig Univ Fac Sci Dept Math Zagazig Egypt

The spectral distribution exp( ), where {} are the eigenvalues of the negative Laplacian -△=- in the (x^1,x^2)-plane, is studied for a variety of domains, where -∞< t <∞ and i=(1/2)(-1) . The dependence of (t)on t... 详细信息

The spectral distribution exp( ), where {} are the eigenvalues of the negative Laplacian -△=- in the (x^1,x^2)-plane, is studied for a variety of domains, where -∞main and the boundary conditions are analyzed. Particular attention is given to a general bounded domain Ω in R^2 with a smooth boundary Ω, where a finite number of piecewise smooth Dirichlet, Neumann and Robin boundary conditions on the piecewise smooth parts Γj(j = 1,……,n) of Ω are considered such that Some geometrical properties of Ω(e.g., the area of Ω, the total lengths of the boundary, the curvature of its boundary, etc.) are determined, from the asymptotic expansions of (t) for |t| → 0.

关键词： Inverse problem spectral distribution wave equation eigenvalues