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Nuclear Science and Techniques 2017年第10期28卷 95-101页

作者： S.Talebi m.m.Valoujerdi Department of Energy Engineering and Physics AmirkabirUniversity of Technology424 Hafez AvenueP.O.Box 15875-4413TehranIran

The present paper discusses entropy generation in fully developed turbulent flows through a subchannel,arranged in square and triangle arrays. Entropy generation is due to contribution of both heat transfer and pressure drop. Our main objective is to study the effect of key parameters such as spacer grid, fuel rod power distribution,Reynolds number Re, dimensionless heat power ω, lengthto-fuel-diameter ratio λ, and pitch-to-diameter ratio ξ on subchannel entropy generation. The analysis explicitly shows the contribution of heat transfer and pressure drop to the total entropy generation. An analytical formulation is introduced to total entropy generation for situations with uniform and sinusoidal rod power distribution. It is concluded that power distribution affects entropy generation.A smoother power profile leads to less entropy *** entropy generation of square rod array bundles is more efficient than that of triangular rod arrays, and spacer grids generate more entropy.

关键词：熵产生子信道燃料棒三角形正方形性能分析热工水力生成方法

NLO response of derivatives of benzene, stilbene and diphenylacetylene：mP2 and DFT calculations

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Chinese Journal of Chemical Engineering 2017年第6期25卷 800-808页

作者： A.m. Elhorri m. Zouaoui-Rabah Laboratoire de microscopie Microanalyse et Spectroscopie Mol&ulaire Faculty of Sciences Djillali Liabes University of Sidi-Bel-Abbes 22000 Sidi-BeI-Abbes Algeria

mP2 method and different functionals such as m06-HF, m06-2X, CAm-B3 LYP, PBE0, B3 LYP and m06 L incorporating different XC amounts were used to calculate the static first hyperpolarizabilies β(0) of eight molecules which are derivatives of benzene, stilbene and diphenylacetylene. The values were then compared to the experimental ones. The m06-2X functional was then selected for further calculations. NBO calculations were also performed to define the intramolecular charge transfer in each molecule. TD-DFT calculations were performed taking into account the solvent effect using the IEF-PCm formalism. Some parameters characterizing the vertical transitions such as the wavelength of the maximum absorption λ_(max) were compared to the experimental ones. Finally,solvation Gibbs free enthalpy ΔG_(solv) values have also been examined in order to determine which the specific solvent for a given molecule is.

关键词： First hyperpolarizability DFT TD-DFT Push-pull molecules NBOCharge transfer

Some studies of the interaction between two two-level atoms and SU(1,1) quantum systems

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Chinese Physics B 2018年第10期27卷 116-122页

作者： T m El-Shahat m Kh Ismail Faculty of Science Al-Azhar University. Assiut 71524 Egypt

Herein, we present an approach to look for the best phenomenon to measure quantum correlation. The system of two isolated qubits each interacting with a single-mode cavity was theoretically created to study the quantum correlation. Some of the phenomena, such as the quantum discord and concurrence, were generated through such a system. The influences of initial state purity, qubit motion, and detuning parameters were discussed for the phenomena. These parameters for a specific value show that the behavior of phenomena are analogous. It is interesting to mention that some values of detuning undergo a sudden death of phenomena, and the quantum discord still captures the qubits quantum correlation. We predict that the quantum discord may be a better measure of quantum correlation than concurrence.

关键词： an isolated atom with a cavity SU (1,1) quantum discord concurrence

Optical and electrical properties of electrochemically deposited polyaniline/CeO2 hybrid nanocomposite film

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Journal of Semiconductors 2011年第4期32卷 25-30页

作者： Anees A.Ansari m.A.m.Khan m.Naziruddin Khan Salman A.Alrokayan m.Alhoshan m.S.Alsalhi King Abdullah Institute for Nanotechnology King Saud UniversityRiyadh-11451P.O.Box-2454Saudi Arabia Department of Chemical Engineering King Saud UniversityP.O.Box 800Riyadh 11421Saudi Arabia

This paper reports the optical and electrical properties of electrochemically deposited polyaniline （PANI）/cerium oxide（CeO;） hybrid nano-composite film onto indium-tin-oxide（ITO） glass ***-visible spectroscopy andⅠ-Ⅴcharacteristic were performed to study the optical and electrical parameters of the electrochemically deposited *** film exhibited a strong absorption below 400 nm（3.10 eV） with a well defined absorbance peak at around 285 nm（4.35 eV）.The estimated band gap of the CeO;sample was 3.44 eV,higher than bulk CeO;powder（E;= 3.19 eV） due to the quantum confinement *** and electrochemical characteristics indicated that the electrical properties of PANI/CeO;hybrid nanocomposite film arc dominated by PANI doping.

关键词： cerium oxide polyaniline nanocomposite optical properties electrical properties

Approximate energies and thermal properties of a position-dependent mass charged particle under external magnetic fields

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Chinese Physics B 2017年第6期26卷 22-30页

作者： m Eshghi H mehraban S m Ikhdair Young Researchers and Elite Club Central Tehran BranchIslamic Azad UniversityTehranIran Faculty of Physics Semnan UniversitySemnanIran Department of Physics Faculty of ScienceAn-Najah National UniversityNablusWest BankPalestine Department of Electrical Engineering Near East UniversityNicosiaNorthern CyprusMersin 10Turkey

We solve the Schrodinger equation with a position-dependent mass（PDm） charged particle interacted via the superposition of the morse-plus-Coulomb potentials and is under the influence of external magnetic and Aharonov–Bohm（AB） flux fields. The nonrelativistic bound state energies together with their wave functions are calculated for two spatially-dependent mass distribution functions. We also study the thermal quantities of such a system. Further, the canonical formalism is used to compute various thermodynamic variables for second choosing mass by using the Gibbs formalism. We give plots for energy states as a function of various physical parameters. The behavior of the internal energy, specific heat, and entropy as functions of temperature and mass density parameter in the inverse-square mass case for different values of magnetic field are shown.

关键词： Schr?dinger equation morse-plus-Coulomb potentials position-dependent mass distribution functions perpendicular magnetic and Aharonov–Bohm flux fields

Kachchh (India) earthquake 2001——causes,severity and impact on groundwater resources

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Journal of Environmental Sciences 2003年第4期15卷 500-505页

作者： m.A.Khan m.L.Sharma CentralAridZoneResearchInstitute CentralAridZoneResearchInstitute Jodhpur342003IndiaJodhpur342003India

Earthquake 2001 in Bhuj region of Kachchh district of Gujarat(India) was one of the most devastating earthquakes in the Indian history. This earthquake has caused severe damage to human life and properties. The impact of earthquake on groundwater resources at many locations was significant. Steep rise in static water level due to earthquake was observed at Bhachau and Chandarani. At other location groundwater followed the declining trend.

关键词： earthquake geology groundwater Bhuj, Kachchh

Relativistic effect of pseudospin symmetry and tensor coupling on the mie-type potential via Laplace transformation method

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Chinese Physics B 2014年第12期23卷 44-49页

作者： m.Eshghi S.m.Ikhdair Young Researchers and Elite Club Central Tehran Branch Islamic Azad University Department of Physics Faculty of Science An-Najah National University

A relativistic mie-type potential for spin-1/2 particles is studied. The Dirac Hamiltonian contains a scalar S（r） and a vector V（r） mie-type potential in the radial coordinates, as well as a tensor potential U（r） in the form of Coulomb potential. In the pseudospin（p-spin） symmetry setting Σ = Cps and Δ = V（r）, an analytical solution for exact bound states of the corresponding Dirac equation is found. The eigenenergies and normalized wave functions are presented and particular cases are discussed with any arbitrary spin–orbit coupling number κ. Special attention is devoted to the caseΣ = 0 for which p-spin symmetry is exact. The Laplace transform approach（LTA） is used in our calculations. Some numerical results are obtained and compared with those of other methods.

关键词： Dirac equation mie-type potential Laplace transform approach tensor interaction p-spin symmetry

NUmERICAL LOCALIZATION OF ELECTROmAGNETIC ImPERFECTIONS FROm A PERTURBATION FORmULA IN THREE DImENSIONS

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Journal of Computational mathematics 2008年第2期26卷 149-195页

作者： m.Asch S.m.mefire LAmFA Université de PicardieCNRs33rue Saint-Leu80039 AmiensFrance CmAP Ecole PolytechniqueCNRSRoute de Saclay91128 PalaiseauFrance

This work deals with the numerical localization of small electromagnetic inhomogeneities. The underlying inverse problem considers, in a three-dimensional bounded domain, the time-harmonic maxwell equations formulated in electric field. Typically, the domain contains a finite number of unknown inhomogeneities of small volume and the inverse problem attempts to localize these inhomogeneities from a finite number of boundary measurements. Our localization approach is based on a recent framework that uses an asymptotic expansion for the perturbations in the tangential boundary trace of the curl of the electric field. We present three numerical localization procedures resulting from the combination of this asymptotic expansion with each of the following inversion algorithms： the Current Projection method, the mUltiple Signal Classification （mUSIC） algorithm, and an Inverse Fourier method. We perform a numerical study of the asymptotic expansion and compare the numerical results obtained from the three localization procedures in different settings.

关键词： Inverse problems maxwell equations Electric fields Three-dimensional inho-mogeneities Electrical impedance tomography Current projection method mUSIC algo-rithm FFT Edge elements Numerical boundary measurements

Effect of Y^(3+), Gd^(3+) and La^(3+) dopant ions on structural, optical and electrical properties of o-mullite nanoparticles

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Journal of Rare Earths 2014年第1期32卷 37-42页

作者： m.m.S.Sanad m.m.Rashad E.A.Abdel-Aal m.F.El-Shahat K.Powers Central metallurgical R & D Institute Particle Engineering Research Center University of Florida Faculty of Science Ain Shams University

Dielectric ceramics of m（x）Al6（1-x）Si2O13 doped mullite were synthesized via co-precipitation technique. The X-ray diffrac-tion profiles revealed that these nanoparticles were crystallized well and the volume of mullite unit cell was increased as a function of the ionic radius of dopant ion. TEm images showed regular orthorhombic crystal morphology for the pure mullite sample. meanwhile, the doped samples exhibited slightly distorted crystal morphology of larger particle sizes. DSC thermograms evinced that the exo-thermic peak temperature of mullite was shifted to the lower value with m3＋ion insertion. The photoluminescence spectra were stud-ied for mullite samples, and it was found that the intensity of the emission spectra was affected by the m3＋ion type. It was found that, Y3＋doped mullite achieved the minimum dielectric loss value of 0.01 in the radio wave frequency region （1 mHz）. meanwhile, Gd3＋doped mullite achieved the minimum dielectric loss value of 0.09 in the microwave frequency region （1 GHz）.

关键词： rare earths doped mullite photoluminescence crystallization temperature dielectric ceramics

The performance of a dissipative electrooptomechanical system using the Caldirola–Kanai Hamiltonian approach

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Communications in Theoretical Physics 2023年第7期75卷 123-131页

作者： m m Atabaki m K Tavassoly A Behjat m Hassani Nadiki K Javidan Optics and Laser Group Faculty of PhysicsYazd UniversityYazdIran Department of Physics School of SciencesFerdowsi University of MashhadMashhad 91775-1436Iran

By combining all optical,electronic,and mechanical capabilities,electro-optomechanical systems,along with the use of mechanical displacement,the conversion of low-frequency electrical signals into much higher-frequency optical signals is *** process provides several capabilities that have very important applications in various fields,including classical,as well as quantum *** this regard,the inevitable effect of dissipation on the performance indicators of such systems is one of the important issues affecting its *** approach for investigating the effect of dissipation is based on a time-dependent Hamiltonian has been known as the Caldirola-Kanai(CK)Hamiltonian,wherein the exponentially increasing mass,i.e.m(t)=m0(eγt)enters the mechanical oscillator *** this approach shows that,the performance of the system under the influence of dissipation with CK Hamiltonian formalism,in which the dissipation terms are embedded in the Hamiltonian,are more logical,analytical,and reliable than considering the effect of dissipation with the phenomenological method(including the dissipation effects in the equations of motion by hand),which has been recently used in Bagci et al.(Nature,507,81,2014).In our method,it is also possible to monitor the performance of the system via the adjustment of dissipation components,i.e.,resistance R and reactance L(and CK damping parameterγ)in the electrical(mechanical membrane)part of the system.

关键词： dissipative system electro-optomechanical system Caldirola-Kanai Hamiltonian