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Influence of the Choice of NN Potential model on γd→τ~0d Observables near η-Threshold

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Chinese Physics Letters 2016年第4期33卷 14-18页

作者： e.m.Darwish Physics Department Faculty of ScienceTaibah University Physics Department Faculty of ScienceSohag University

Influence of the choice of the NN potential model governing the deuteron wave function on the observables for coherent π0-photoproduction on the deuteron near η-threshom is investigated by using a three-body model for the intermediate ηN N system with separable two-body interactions. Results for unpolarized differential cross section and polarization observables are predicted. It is revealed that the choice of the NN potential model has a visible effect on the differential cross section and most of the polarization observables, especially in the photon energy range of 600-800 meV and extreme backward pion angles. We find that the deviation among results obtained by using different deuteron wave functions is quite large. The use of the CD-Bonn NN potential for deuteron wave function doubles the differential cross section in this kinematic region. Compared with the experimental data from CLAS collaboration for differential cross section, sizeable discrepancies are found.

关键词： of in Observables near Threshold NN that for on CLAS

SOme OSCILLATION CRITeRIA FOR SeCOND ORDeR NONLINeAR FUNCTIONAL ORDINARY DIFFeReNTIAL eQUATIONS

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Acta mathematica Scientia 2007年第3期27卷 602-610页

作者： e.m.e.Zayed m.A.el-moneam mathematics Department Faculty of ScienceZagazig UniversityZagazigEgypt

The main objective of this article is to study the oscillatory behavior of the solutions of the following nonlinear functional differential equations（a（t）x＇（t））＇＋δ1p（t）x＇（t）＋δ2q（t）f（x（g（t））） = 0,for 0 ≤ to≤ t, where 51 = ：el and δ±1. The functions p,q,g ： [t0, ∞） → R, f ： R → are continuous, a（t）〉 0,p（t） ≥0,q（t）〉 0 for t ≥ to,lirn g（t） = ∞, and q is not identically zero on any subinterval of [to, ∞）. moreover, the functions q（t）, g（t）, and a（t） are continuously differentiable.

关键词： Oscillatory and nonoscillatory solutions nonlinear functional differential equations

Superplasticity-like creep behavior of coarse grained ternary Al alloys

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Transactions of Nonferrous metals Society of China 2010年第4期20卷 564-571页

作者：乔军 e.m.TALeFF College of materials Science and engineering University of Science and Technology Liaoning Department of mechanical engineering University of Texas at Austin

enhanced tensile ductilities in coarse grained Al-mg-Zn and Al-mg-Fe materials were *** materials were Al-2mg-5Zn,Al-3mg-5Zn,Al-4mg-5Zn,Al-3mg-0.11Fe,Al-3mg-0.27Fe,and *** elongation-to-failure tests were conducted at constant cross-head speed and constant temperatures from 300 to 450℃.Strain rate change tests were conducted at a constant temperature from 300 to 450℃and in strain-rate range from 4.31×10-5to 1.97×*** results show that over 100%ductilities are consistently achieved in these *** superplasticity-like behavior is rate-controlled by solute-drag *** ternary Zn and Fe additions do not have an adverse effect on solute-drag creep and ductility,they increase stress exponent and its sensitivity to mg content during solute-drag creep.

关键词： Al-mg alloys superplasticity solute-drag creep tensile ductility strain-rate sensitivity

monte Carlo simulation of lattice analysis of complex LaCeTh0.1CuOy using ion bombardment technique

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

作者： m.e.emetere Department of Physics Covenant University Canaanland Department of mechanical engineering Science University of Johannesburg

Ion bombardment analysis of perovskite materials is challenging owing to their peculiar *** shortcoming renders the reliability on the technique somewhat *** this research,three structured modifications(i.e.,scan angle,low energy,and large ion bombardment)were adopted to improve the ion bombardment analysis of 99,999 ions using monte Carlo *** modified technique was used to analyze the effects of a chemically pressurized‘‘A’’site in the perovskite lattice *** LaCeTh0.1Cu2Oy compound was used in this *** the low probing energy,it was observed that the high number of ions bombarding the material resulted in external pressure on the lattice structure of the ***,the chemically pressurized‘‘A’’site perovskite material was characterized by lattice mismatch,lattice fluctuations,grain boundary collapse,and oxygen *** novel discovery of this research is the inter-and intra-extended lattice mismatches that are likely to ***,further investigation of the connection between inter-and intraextended lattice mismatches is recommended as they may enable fabrication of room-temperature superconductors.

关键词： Lattice mismatch Ion bombardment Chemical pressure Scan angle

Buckling and large deflection behaviors of radially functionally graded ring-stiffened circular plates with various boundary conditions

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Applied mathematics and mechanics(english edition) 2016年第9期37卷 1131-1152页

作者： m.e.GOLmAKANI m.emAmI Department of mechanical engineering Mashhad BranchIslamic Azad University

The buckling and large deflection behaviors of axis-symmetric radially functionally graded （RFG） ring-stiffened circular plates are investigated by the dynamic relaxation （DR） method combined with the finite difference discretization technique. The material properties of the constituent components of the RFG plate are assumed to vary continuously according to the mori-Tanalka distribution along the radial direction. The nonlinear governing equations are obtained in the incremental form based on the firstorder shear deformation plate theory （FSDT） and the von Karman relations for large deflection. In the buckling analysis, an external in-plane load is applied to the plate in- crementally so that, in each load-step, the incremental form of the governing equations can be solved by a numerical code prepared based on the DR method. After converging the DR code in the first increment, the latter load-step is added to the previous one, and the program is repeated again. The critical buckling load is determined from the compressive load-displacement curve obtained by solving the incremental form of the governing equations. Based on the present incremental form of formulation, a bending analysis can also be conducted if the whole load is applied simultaneously. Finally, a detailed parametric study is carried out to investigate the influences of various boundary conditions, grading indices, thickness-to-radius ratios, stiffener＇s positions and depths on the critical buckling load, and displacements and stresses resulted from the bending analysis. It is observed that the effect of the stiffener on the results is much greater in the functionally graded plate with higher material grading indices. The results also reveal that, by increasing the depth of the stiffer, the values of ascending the critical buckling load are approximately identical for both simply supported and clamped boundary conditions.

关键词： buckling large deflection functionally graded stiffened plate dynamicrelaxation method

DNA Dynamics Studied Using the Homogeneous Balance method

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Chinese Physics Letters 2012年第8期29卷 9-11页

作者： e.m.e.Zayed A.H.Arnous mathematics Department Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

We employ the homogeneous balance method to construct the traveling waves of the nonlinear vibrational dynamics modeling of *** new explicit forms of traveling waves are *** is shown that this method provides us with a powerful mathematical tool for solving nonlinear evolution equations in mathematical *** and weaknesses of the proposed method are discussed.

关键词： traveling nonlinear method

The Asymptotics of the Heat Semigroup for a General Bounded Domain with mixed Boundary Conditions

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Acta mathematica Sinica,english Series 2000年第4期16卷 627-636页

作者： e. m. e. Zayed mathematics Department. Faculty of Science. Zagazig University. Zagazig. egypt

Small-time asymptotics of the trace of the heat semigroup 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 domain Ω with a smooth boundary Ω. where a finite number of Dirichlet. Neumann and Robin boundary conditions, on the piecewise smooth parts Γi（i=1, ..., n） of )Ω such that)Ω=∪i=1nΓ are considered. Some geometrical properties associated with Ω are determined

关键词： Heat semigroup Inverse problem mixed boundary conditions eigenvalues

Systematic review of the old and new concepts in the epithelial-mesenchymal transition of colorectal cancer

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World Journal of Gastroenterology 2016年第30期22卷 6764-6775页

作者： Simona Gurzu Camelia Silveanu Annamaria Fetyko Vlad Butiurca Zsolt kovacs Ioan Jung Department of Pathology University of Medicine and Pharmacy of Tirgu-Mures Department of Surgery University of Medicine and Pharmacy of Tirgu-Mures Departments of Genetics and Biochemistry University of Medicine and Pharmacy of Tirgu-Mures

epithelial-to-mesenchymal transition(emT) is defined as the transformation of an epithelial cell into a spindle cell with the loss of membrane e-cadherin expression and the gain of mesenchymal markers positivity. In the field of colorectal cancer(CRC), first data about emT was published in 1995 and more than 400 papers had been written up to march 2016. most of them are focused on the molecular pathways and experimentally-proved chemoresistance. In the present article, an update in the field of emT in CRC based on the review of the literature and personal experience of the authors is presented. The information about the molecular and immunohistochemical(IHC) particularities of these processes and their possible role in the prognosis of CRC were also up-dated. This article focuses on the IHC quantification of the emT, the immunoprofile of tumor buds and on the relation between emT, angiogenesis, and stem cells activation. The emT-induced chemoresistance vs chemotherapyor radiotherapy-induced emT and cellular senescence was also synthesized for both conventional and targeted therapy. As a future perspective, the emTangiogenesis-stemness link could be used as a possible valuable parameter for clinical follow-up and targeted therapeutic oncologic management of patients with CRC. Association of dexamethasone and angiotensin converting enzyme inhibitors combined with conventional chemotherapies could have clinical benefits in patients with CRC. The main conclusion is that, although many studies have been published, the emT features are still incompletely elucidated and newly discovered emT markers provide confusing data in understanding this complicated process, which might have significant clinical impact.

关键词： Angiogenesis Colorectal cancer Budding epithelial-mesenchymal transition Chemoresistance

Structural,morphological and optical properties of new eu-doped and vacancied lead molybdato-tungstates

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Journal of Rare earths 2018年第6期36卷 635-641页

作者： m.Piotkowska e.Tomaszewicz Faculty of Chemical Technology and engineering Department of Inorganic and Analytical ChemistryWest Pomeranian University of TechnologySzczecinAI.Piast6w 4271-065 SzczecinPoland

A new tetragonal,scheelite-type Pb_(1-3 x)■_xeU_(2 x)(moO_4)_(1-3 x)(WO_4)_(3 x)(0 3 eV) and their band gap nonlinearly decreases with increasing dopant concentration.

A new tetragonal,scheelite-type Pb_(1-3 x)■_xeU_(2 x)(moO_4)_(1-3 x)(WO_4)_(3 x)(0enotes A-site vacancies) solid solution was synthesized via solid state reaction method. The X-ray diffraction(XRD) and scanning electron microscopy(Sem) results confirm the formation of single, tetragonal scheelite-type phases(space group I4_1/a) with the average crystallite size in the range of ～20-100 μm. Substitution of Pb^(2+) with eu^(3+) is relatively easy despite the large difference in ionic radii, and the formation of vacancies is necessary to compensate the excess positive charge in PbmoO_4 framework. A change in lattice parameters(both a and c as well as lattice parameter ratio c/a) and progressive deformation of moO_4 and WO_4 tetrahedra with increasing eu concentration are observed. Thermal stability of eu-doped materials strongly depends on the concentration of eu3+ ions. The Pb_(1-3 x)■_xeu_(2 x)(moO_4)_(1-3 x)(WO_4)_(3 x) solid solution for x=0.0098 shows the highest melting point(1057 ℃) which is slightly higher than that of pure PbmoO_4(1040 ℃). The UV-vis diffuse reflectance spectroscopy(DRS) and the Tauc plots were used to extrapolate the optical indirect band gap(e_g) of doped materials. eu-doped ceramics are insulators(e_g > 3 eV) and their band gap nonlinearly decreases with increasing dopant concentration.

关键词： molybdato-tungstate Scheelites Thermal stability Optical properties Rare earths