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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

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

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

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

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Algebra Colloquium 2020年第2期27卷 193-198页

作者： s.m.Robati Department of mathematics Faculty of Science Imam Khomeini International UniversityQazvinIran

Let G be a group,and let →/ΓC(G) be a digraph whose vertices are the nontrivial conjugacy classes of G and there is an arc from a vertex C to a vertex C' if and only if C≠C' and(C)■(C').In this paper,we characteri... 详细信息

关键词： conjugacy classes posets graphs finite groups

Anomalous reactivity of thermo-bioconvective nanofluid towards oxytactic microorganisms

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Applied mathematics and mechanics(English Edition) 2020年第5期41卷 711-724页

作者： s.I.ABDELsALAm m.m.BHATTI Basic science Department Faculty of EngineeringThe British University in EgyptAl-Shorouk CityCairo 11837Egypt Instituto de matemáticas-Juriquilla Universidad Nacional Autónoma de MéxicoBlvd.Juriquilla 3001Quer´etaro 76230M´exico College of mathematics and systems science Shandong University of Science and TechnologyQingdao 266590Shandong ProvinceChina

The peristaltic flow of a non-Newtonian nanofluid with swimming oxytactic microorganisms through a space between two infinite coaxial conduits is investigated. A variable magnetic field is applied on the flow. The bioconvection flow and heat transfer in the porous annulus are formulated, and appropriate transformations are used, leading to the non-dimensionalized ruling partial differential equation model. The model is then solved by using the homotopy perturbation scheme. The effects of the germane parameters on the velocity profile, temperature distribution, concentration distribution, motile microorganism profile, oxytactic profile, pressure rise, and outer and inner tube friction forces for the blood clot and endoscopic effects are analyzed and presented *** is noticed that the pressure rise and friction forces attain smaller values for the endoscopic model than for the blood clot model. The present analysis is believed to aid applications constituting hemodynamic structures playing indispensable roles inside the human body since some blood clotting disorders, e.g., haemophilia, occur when some blood constituents on the artery wall get confined away from the wall joining the circulation system.

关键词： oxytactic swimming microorganism swimming variable magnetic field blood clotting endoscopy non-Newtonian fluid

Large scale silver nanowires network fabricated by meV hydrogen (H＋) ion beam irradiation

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Chinese Physics B 2016年第4期25卷 268-273页

作者： Honey s Naseem s Ishaq A maaza m Bhatti m T Wan D Center of Excellence in solid state Physics University of the Punjab Lahore Pakistan National Center for Physics Quaid-i-Azam University Islamabad 44000 Pakistan UNEsCO-UNIsA Africa Chair in Nanosciences/Nanotechnology College of Graduate Studies University of South Africa Muckleneuk ridge P. O. Box 392 Pretoria South Africa Nanosciences African Network (NANOAFNET) iThemba LABS National Research Foundation Old Faure road P. O. Box 722 Somerset West 7129 South Africa Department of Physics Bahauddin Zakariya University Multan 60800 Pakistan school of materials science and Engineering Shanghai University Shanghai 201900 China

A random two-dimensional large scale nano-network of silver nanowires （Ag-NWs） is fabricated by meV hydrogen （H＋） ion beam irradiation. Ag-NWs are irradiated under H＋ ion beam at different ion fluences at room temperature. The Ag-NW network is fabricated by H＋ ion beam-induced welding of Ag-NWs at intersecting positions. H＋ ion beam induced welding is confirmed by transmission electron microscopy （TEm） and scanning electron microscopy （sEm）. moreover, the structure of Ag NWs remains stable under H＋ ion beam, and networks are optically transparent. morphology also remains stable under H＋ ion beam irradiation. No slicings or cuttings of Ag-NWs are observed under meV H＋ ion beam irradiation. The results exhibit that the formation of Ag-NW network proceeds through three steps： ion beam induced thermal spikes lead to the local heating of Ag-NWs, the formation of simple junctions on small scale, and the formation of a large scale network. This observation is useful for using Ag-NWs based devices in upper space where protons are abandoned in an energy range from meV to GeV. This high-quality Ag-NW network can also be used as a transparent electrode for optoelectronics devices.

关键词： Ag nanowires H+ ion irradiation nanowelding large scale nano-network optical properties

Performance evaluation of a modified step-feed anaerobic/anoxic/oxic process for organic and nutrient removal

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Chinese Journal of Chemical Engineering 2016年第3期24卷 394-403页

作者： A.R.majdi Nasab s.m.soleymani m.Nosrati s.m.mousavi Biotechnology Group Faculty of Chemical EngineeringTarbiat Modares UniversityTehranlran

A pilot scale modified step-feed process was lmproved to increase nutrient/N ano P） ano organic removal operations from municipal wastewater. It combined the step-feed process and a method named ＂University of Cape Town （UCT）＂. The effect of nutrient ratios and inflow distribution ratios were studied. The highest uptake efficiency of 95% for chemical oxygen demand （COD） has been achieved at the inflow distribution ratio of 40/35/25. However, maximum removal efficiency obtained for total nitrogen （TN） and phosphorus at 93% and 78%, respectively. The average mixed liquor suspended solids （mLss） was 5500 mg·L- 1. In addition, convenient values for dissolved oxygen （DO） concentration, and pH were obtained throughout different stages. The proposed system was identified to be an appropriate enhanced biological nutrient removal process for wastewater treatment plants owing to relatively high nutrient removal, sturdy sludge settle ability and COD removal.

关键词： Biological nutrient remova step-feed bioreactor Nitrification Denitrification Phosphorus removal

Development of Nano-tetragonal Zirconia-Incorporated Ni–P Coatings for High Corrosion Resistance

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Acta metallurgica sinica(English Letters) 2019年第4期32卷 481-494页

作者： s.m.A.shibli K.s.Chinchu m.Ameen sha Department of Chemistry University of KeralaKariavattom CampusThiruvananthapuram

Pure tetragonal 10-20-nm-size zirconia-based Ni-P composite coating was developed. The physicochemical and electrochemical characteristics including corrosion resistance of the coating were investigated. The Ni-P-nano-tetragonal zirconia coating was partially crystalline having face-centered cubic phase. The coating had very high corrosion resistance due to its dense compact morphology and low surface roughness. The Ni-P-nano-tetragonal zirconia coatings exhibited a cathodic shift of open-circuit potential(OCP) in the range from-0.340 to-0.520 V. A high polarization resistance of the order of 13.2 kΩ/cm^2 and low corrosion current density of 3.9 μA/cm^2 were achieved due to the effective incorporation of zirconia into the coating.

关键词： Composites Corrosion resistance substrates Ni–P ZrO2

Earthquake response of asymmetric building with mR damper

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Earthquake Engineering and Engineering Vibration 2014年第2期13卷 305-316页

作者： s.D.Bhart s.m.Dumne m.K.shrimali Department of Civil Engineering malaviya National Institute of Technology Jaipur Govt.Poly.College Nashik Maharashtra India

Plan asymmetric buildings are very susceptible to earthquake induced damage due to lateral torsional coupling, and the corners of these systems suffer heavy damage during earthquakes. Therefore, it is important to investigate the seismic behavior of an asymmetric plan building with mR dampers. In this study, the effectiveness of mR damper-based control systems has been investigated for seismic hazard mitigation of a plan asymmetric building. Furthermore, the infl uence of the building parameters and damper command voltage on the control performance is examined through parametric study. The building parameters chosen are eccentricity ratio and frequency ratio. The results show that the mR damper-based control systems are effective for plan asymmetric systems.

关键词： torsional coupling plan asymmetric mR damper