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Progress in Natural Science:Materials International 2016年第6期26卷 650-656页

作者： A.Farhoumand r.Ebrahimi Department of Materials Science and Engineering School of Engineering Shiraz University

Finite element method was employed to investigate the effect of process parameters of plastic deformation behavior in Forward-Backward-radial Extrusion(FBrE) process. The result of an axisymmetric model shows that the friction between die components and the sample has a substantial effect on the material flow *** strain heterogeneity index(SHI) slightly decreases with an increase in friction, large portion of the sample experiences significant strain heterogeneity. Increasing the friction factor also localizes the strain heterogeneity effect in the backward section, and spread the effect in the forward section. Decreasing the friction in the FBrE process can reduce the amount of the strain heterogeneity in the product while decreases the required punch force substantially. Furthermore, an increase in gap thickness increases the deformation in the area close to the lower punch at the expense of the area in the vicinity of the upper punch. The numerical simulation has a good agreement with the experimental results which confirms the accuracy of the proposed finite element model.

关键词： Finite element analysis Extrusion Forming Plastic deformation Strain heterogeneity

Transient Thermal Management Comparison of a Microprocessor Using PCMs in Various Configurations

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Journal of Thermal Science 2011年第6期20卷 516-520页

作者： Thenmozhi r Sharmeela C Natarajan P Velraj r Ganthipathy Tulsis' Engineering College AUIndia Anna University ChennaiIndia Bharathidasan Engineering college AUIndia

There has been a strong interest in the use of Phase Change Materials (PCMs) for the transient thermal abatement of high powered *** paper presents a set of transient computational analysis for selected IC packages with the purpose of calibrating the merits of PCM in different *** transient analysis of high powered microprocessors with heat sinks was performed as a benchmark for comparison with the same microprocessors fitted with PCM in the following configurations:a) PCM imbedded into the finned region of the heat sink,b) PCM mounted between the microprocessor and heat sink,c) sealed PCM underfill to the microprocessor and d) PCM fitted to the underside of the printed circuit board directly beneath the *** analysis was performed using a commercial CFD tool together with an approximation to the phase change mechanism using the slope *** indicate the merit of each configuration.

关键词： Phase Change Materials CFD Thermal Management Transient Latent heat

Computer Modelling of Metal Dissolution in the Presence of Aqueous Electrolyte

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Chinese Physics Letters 2002年第3期19卷 389-390页

作者： r.I.Eglitis M.r.Philpott UniversitatOsnabruck FachbereichPhysikD-49069OsnabruckGermany DepartmentofMaterialsScience NationalUniversityofSingapore10KentRidgeCrescentSingapore119260

The semi-empirical Hartree-Fock intermediate neglect of differential overlap (INDO) method was used to explore the potential energy surface of adsorbed water molecules and to speculate, using fairly simple cluster models, on the reaction path followed by metal ions leaving the surface. As an example, INDO calculations were used to calculate the potential energy curve for a metal atom leaving the surface and entering into a solvation cage composed of tetrahedral arranged water molecules. The effect of adding a NaCl ion pair to the system with the halide ion above the dissolving atom was also explored.

关键词： Metals

Carbon nanotubes on unsteady MHD non-Darcy flow over porous wedge in presence of thermal radiation energy

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Applied Mathematics and Mechanics(English Edition) 2016年第8期37卷 1031-1040页

作者： r.KANDASAMY r.MOHAMMAD I.MUHAIMIN research Centre for Computational Mathematics Faculty of ScienceTechnology and Human DevelopmentUniversiti Tun Hussein Onn Malaysia

The thermal radiation energy is the clean energy with a much lower environmental impact than the conventional energy. The objective of the present work is to investigate theoretically the effect of copper nanoparticles and carbon nanotubes （CNTs） in the presence of base fluid （water） with the variable stream condition due to the thermal radiation energy. Single-walled carbon nanotubes （SWCNTs） in the presence of base fluid flow over a porous wedge play a significant role compared to those of copper nanoparticles on absorbing the incident solar radiation and transiting it to the working fluid by convection.

关键词： carbon nanotube (CNT) copper nanoparticle magnetic field thermal radiation energy

Holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： H r Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

recently, reconsidering the rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. Hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~H^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

Investigation of neutron density distribution of^208Pb nucleus when the proton density is constrained to its experimental distribution

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Chinese Physics C 2020年第8期44卷 132-138页

作者： A.r.Abdulghany Physics Department Faculty of ScienceCairo UniversityGizaEgypt

In this study,two novel improvements for the theoretical calculation of neutron distributions are ***,the available experimental proton distributions are used as a constraint rather than inferred from the ***,the recently proposed distribution formula,d3pF,is used for the neutron density,which is more detailed than the usual shapes,for the first time in a nuclear structure calculation.A semi-microscopic approach for binding energy calculation is considered in this ***,the proposed improvements can be introduced to any other *** ground state binding energy and neutron density distribution of 208Pb nucleus are calculated by optimizing the binding energy considering three different distribution *** implementation of the proposed improvements leads to qualitative and quantitative improvements in the calculation of the binding energy and neutron density *** calculated binding energy agrees with the experimental value,and the calculated neutron density exhibits fluctuations within the nuclear interior,which corresponds with the predictions of self-consistent approaches.

关键词： nuclear density density-fluctuation binding energy

Nonlinear and non-CP gates for Bloch vector amplification

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Communications in Theoretical Physics 2023年第10期75卷 51-59页

作者： Michael r Geller Center for Simulational Physics University of GeorgiaAthensGA 30602United States of America

Any state r=(x,y,z)of a qubit,written in the Pauli basis and initialized in the pure state r=(0,0,1),can be prepared by composing three quantum operations:two unitary rotation gates to reach a pure state r=(x^(2)+y^(2)+z^(2))-1/2×(x,y,z)on the Bloch sphere,followed by a depolarization gate to decrease|r|.Here we discuss the complementary state-preparation protocol for qubits initialized at the center of the Bloch ball,r=0,based on increasing or amplifying|r|to its desired value,then *** vector amplification increases purity and decreases *** can be achieved with a linear Markovian completely positive trace-preserving(CPTP)channel by placing the channel’s fixed point away from r=0,making it nonunital,but the resulting gate suffers from a critical slowing down as that fixed point is *** we consider alternative designs based on linear and nonlinear Markovian PTP channels,which offer benefits relative to linear CPTP channels,namely fast Bloch vector amplification without *** gates simulate a reversal of the thermodynamic arrow of time for the qubit and would provide striking experimental demonstrations of non-CP dynamics.

关键词： nonlinear channels non-completely positive channels Bloch vector amplification

Catalytic degradation of methylene blue by Fenton like system: model to the environmental reaction

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Journal of Environmental Sciences 2004年第2期16卷 285-287页

作者： Sanjay r Thakare Department of Chemistry Science CollegeCongress NagarDepartment of ChemistryScience CollegeCongress Nagar Nagpur India-440012Nagpur India-440012

To develop more efficient chemical methods for the demineralization of organic pollutants from water bodies, which one was also mimic to the nature, a degradation of methylene blue by Fe(Ⅲ) and H 2O 2 in the absence of light instead of Fe(Ⅱ) and H 2O 2 was studied. results showed that use of Fe (Ⅲ) is more promising than Fe(Ⅱ). The present study reflects that Fenton reaction is more efficient, in the presence of a small amount of salicylic acid is added which is a one of the priority pollutant.

关键词： advanced oxidation technology Fenton reaction iron(Ⅲ) catalytic degradation environmental application

Effect of exchange interaction in ferromagnetic superlattices:A Monte Carlo study

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Chinese Physics B 2016年第10期25卷 413-417页

作者： r Masrour A Jabar Laboratory of Materials Processes Environment and Quality Cady Ayyed University National School of Applied Sciences

The Monte Carlo simulation is used to investigate the magnetic properties of ferromagnetic superlattices through the Ising model. The reduced critical temperatures of the ferromagnetic superlattices are studied each as a function of layer thickness for different values of exchange interaction. The exchange interaction in each layer within the interface and the crystal field in the unit cell are studied. The magnetic coercive fields and magnetization remnants are obtained for different values of exchange interaction, different values of temperature and crystal field with fixed values of physical parameters.

关键词： Monte Carlo simulations superlattice critical temperature magnetic coercive field

Study on the Numerical Model of Transonic Wind Tunnel Test Section

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Journal of Thermal Science 2021年第1期30卷 231-241页

作者： LOUDA Petr PŘÍHODA Jaromír Institute of Thermomechanics of the Czech Academy of Sciences Prague 818200Czech Republic Faculty of Mechanical Engineering Czech Technical UniversityPrague 212135Czech Republic

The authors consider numerical simulations of transonic flows through various turbine cascades in a confined channel which approximates boundaries of real wind *** boundaries of the wind tunnel are impermeable or there can be permeable tailboards to diminish shock wave *** mathematical model is based on Favre-averaged Navier-Stokes equations closed by a turbulence model and model of transition to *** mathematical model is solved by an implicit finite volume method with multi-block *** types of turbine blade cascades with subsonic or supersonic inlet are *** results are compared with optical measurements and simulations of periodic *** validity of experimental reference flow parameters in relation to computed flow patterns is discussed.

关键词： perforated wall model transonic wind tunnel turbine blade cascade