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Journal of Sport and Health Science 2018年第1期7卷 123-124页

作者： Mianfang Ruan faculty of Physical education Ningbo University

The debate about the mechanisms of hamstring injuries in sprinting in the Journal of Sport and Health Science reminded me of the discussion of the force enhancement mechanisms in stretch-shortening cycles(SSCs)20 years ago in the Journal of Applied *** controversies concerning the proposed mechanisms were mainly due to the difference in

关键词：损害肌肉原因杂志机制

Five-Dimensional Cosmological Model with Variable G and A

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Chinese Physics Letters 2007年第8期24卷 2185-2188页

作者： H. Baysal I. Yllmaz Department Secondary Science and Mathematics education Education Faculty Canakkale Onsekiz Mart University 17100 Canakkale Turkey Department of Physics Art and Science Faculty Canakkale Onsekiz Mart University 17020 Canakkale Turkey

Einstein＇s field equations with C and A both varying with time are considered in the presence of a perfect fluid for five-dimensional cosmological model in a way which conserves the energy momentum tensor of the matter content. Several sets of explicit solutions in the five-dimensional Kaluza-Klein type cosmological models with variable G and A are obtained. The diminishment of extra dimension with the evolution of the universe for the five-dimensional model is exhibited. The physical properties of the models are examined.

关键词： Five-Dimensional Cosmological Model Variable

Syntheses of Some 3-[1′(1′H)-Substituent-pyrazol-5′-yl] benzo[5,6]coumarins

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Chinese Journal of Chemistry 2002年第7期20卷 670-675页

作者： E-LDEEN Ibrahim Mohey AL-WAKEEL El-Sayed Ismail El-MAWLA Ahmed Gad faculty of education Suez Canal University Port‐said Egypt faculty of Science Suez Canal University Ismailia Egypt

3-[1′ (1′ H)-Substituent-pyrazol-5′-yl] benzo[5, 6] coumarins and3-(1′,2′-oxazol-5′-yl)benzo[5,6]coumarin were prepared via condensation of3-(2′-formyl-1′-chlorovinyl) benzo [5, 6] coumarin with hydrazine derivatives or *** of 3-[1′(1′ H)-pyrazol-5′-yl] benzo[5, 6] coumarin with alkyl halidcs, olefiniccompounds or acid chlorides are described.

关键词： heterocycle synthesis pyrazol-5′-ylbenzo [5, 6] coumarin alkylation atpyrazole nitrogen

Exact Controllability and Asymptotic Analysis for Shallow Shells

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Chinese Annals of Mathematics,Series B 2007年第1期28卷 93-122页

作者： S.KAIZU N.SABU Department of Mathematics faculty of education Ibaraki University 2-1-1BunkyoMitoJapanDepartment of Mathematics Faculty of EducationIbaraki University2-1-1BunkyoMitoJapan

The authors consider the exact controllability of the vibrations of a thin shallow shell, of thickness 2ε with controls imposed on the lateral surface and at the top and bottom of the shell. Apart from proving the existence of exact controls, it is shown that the solutions of the three dimensional exact controllability problems converge, as the thickhess of the shell goes to zero, to the solution of an exact controllability problem in two dimensions.

关键词： Exact controllability Asymptotic analysis Shallow shells

Dynamics of a rotating ring-stiffened sandwich conical shell with an auxetic honeycomb core

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 963-982页

作者： S.JAHANGIRI A.GHORBANPOUR ARANI Z.KHODDAMI MARAGHI Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan ***Iran faculty of Engineering Mahallat Institute of Higher EducationMahallat ***Iran

The free vibration analysis of a rotating sandwich conical shell with a reentrant auxetic honeycomb core and homogenous isotropic face layers reinforced with a ring support is *** shell is modeled utilizing the first-order shear deformation theory(FSDT)incorporating the relative,centripetal,and Coriolis accelerations alongside the initial hoop tension created by the *** governing equations,compatibility conditions,and boundary conditions are attained using Hamilton’s *** trigonometric functions,an analytical solution is derived in the circumferential direction,and a numerical one is presented in the meridional direction via the differential quadrature method(DQM).The effects of various factors on the critical rotational speeds and forward and backward frequencies of the shell are *** present work is the first theoretical work regarding the dynamic analysis of a rotating sandwich conical shell with an auxetic honeycomb core strengthened with a ring support.

关键词： free vibration conical shell rotating shell ring support auxetic honeycomb

Hartree-Fock-Roothaan Calculations for Ground States of Some Atoms Using Minimal Basis Sets of Integer and Noninteger n-STOs

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Chinese Journal of Chemistry 2004年第11期22卷 1262-1266页

作者： GüMü■ Sedat ZSO■AN Telhat Department of Physics Amasya Education Faculty Ondokuz Mayis University 05189 Amasya TURKEYDepartment of Physics Amasya Education Faculty Ondokuz Mayis University 05189 Amasya TURKEY

Hartree-Fock-Roothaan (HFR) calculations for ground states of some atoms, i.e. He, Be, Ne, Ar, and Kr have been performed using minimal basis sets of Slater type orbitals (STOs) with integer and noninteger principal quan-tum numbers (integer n-STOs and noninteger n-STOs). The obtained total energies for these atoms using minimal basis sets of integer n-STOs are in good agreement with those in the previous literature. On the other hand, for the case of minimal basis sets of noninteger n-STOs, although the calculated total energies of these atoms agree well with the results in literature, some striking results have been obtained for atoms Ar and Kr. Our computational re-sults for the energies of atoms Ar and Kr are slightly better than those in literature, by amount of 0.00222 and 0.000054 a.u., respectively. The improvement in the energies of atoms Ar and Kr may result from the efficient cal-culations of one-center two-electron integrals over noninteger n-STOs. For some atomic ions in their ground state, HFR calculations have been carried out using minimal basis sets of noninteger n-STOs. The obtained total energies for these atomic ions are substantially lower than those available in literature.

关键词： Hartree-Fock-Roothaan Slater type orbital

Numerical investigation of circle defining curve for two-dimensional problem with general boundaries using the scaled boundary finite element method

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Frontiers of Structural and Civil Engineering 2019年第1期13卷 92-102页

作者： Chung Nguyen VAN Department of Civil Engineering Faculty of EngineeringChulalongkorn UniversityThailand faculty of Civil Engineering Ho Chi Minh City of Technology and EducationVietNam

The scaled boundary finite element method (SBFEM)is applied to the static analysis of two dimensional elasticity problem,boundary value problems domain with the domain completely described by a circular defining curve. The scaled boundary finite element equations is formulated within a general framework integrating the influence of the distributed body force,general boundary conditions,and bounded and unbounded *** paper investigates the possibility of using exact geometry to form the exact description of the circular defining curve and the standard finite element shape function to approximate the defining *** linear elasticity problems are presented to verify the proposed method with the analytical *** examples show the accuracy and efficiency of the proposed method,and the performance is found to be better than using standard linear element for the approximation defining curve on the scaled boundary method.

关键词： exact geometry circular defining curve general boundaries SBFEM

Higher Electric Multipole Moments for Some Polyatomic Molecules from Accurate SCF Calculations

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Communications in Theoretical Physics 2002年第10期38卷 489-492页

作者： Telhat Ozdogan Department of Physics Education Faculty Ondokuz Mayis University Amasya Turkey

Higher electric multipole moments for the ground-state electronic configuration of some polyatomicmolecules, i.e. CH4, NH3, H2O, were calculated from SCF-HFR wavefunctions using Slater-type orbital basis *** calculated results for electric multipole moments of these molecules are in good agreement with the theoretical andexperimental ones.

关键词： electric multipole moments, Slater-type orbitals, HFR approximation

Structural and Optical Properties of GaAs_(0.5)Sb_(0.5) and In_(0.5)Ga_(0.5)As_(0.5)Sb_(0.5):ab initio Calculations for Pure and Doped Materials

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Chinese Physics Letters 2012年第3期29卷 193-196页

作者： Mazin SH.Othman Khudheir A.Mishjil Nadir F.Habubi Department of General Science Faculty of EducationSoran UniversitySoran-ErbilIraq Department of Physics College of EducationAl-Mustansiriyah UniversityIraq

We perform a first-principles study to evaluate the structural,electronic and optical properties of GaAs_(x)Sb_(1-x) ternary and In_(y)Ga_(1-y)As_(x)Sb_(1-x) quaternary semiconductor alloys up to x=0.5,y=*** employ the Perdew-Burke-Ernzerhof form of the generalized gradient approximation(GGA)within the framework of density functional theory(DFT)by using a simulation *** are carried out in different *** these alloys,lattice parameters and optical band gap energy are *** optical band gaps varywith increasing and decreasing As and In concentrations,*** optical conductivity,absorption and the real part of the dielectric function ε1(ω) are *** results agree well with the theoretical and experimental data available in the literature.

关键词： alloys quaternary ternary

An efficient approach to solving fractional Van der Pol-Duffing jerk oscillator

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Communications in Theoretical Physics 2022年第10期74卷 50-59页

作者： Yusry O El-Dib Department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The motive behind the current work is to perform the solution of the Van der Pol–Duffing jerk oscillator,involving fractional-order by the simplest *** effective procedure has been introduced for executing the fractional-order by utilizing a new method without the perturbative *** approach depends on converting the fractional nonlinear oscillator to a linear oscillator with an integer order.A detailed solving process is given for the obtained oscillator with the traditional system.

关键词： Van der Pol oscillator Duffing jerk oscillator fractional oscillator non-perturbative approach numerical simulation