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Journal of Natural Gas Chemistry 2011年第2期20卷 128-134页

作者： Zahra Hosseini majid Taghizadeh Fereydoon Yaripour Chemical Engineering Department Babol University of Technology Catalyst Research Group Petrochemical Research and Technology Company NPC

The capability of sol-gel and conventional precipitation techniques for the synthesis of nanocrystalline γ-alumina was investigated. These catalysts were used for vapor-phase dehydration of methanol to dimethyl ether in a fixed-bed reactor under the same operating conditions （T = 300 ？C, P = 1 bar, LHSV = 2.8, 11.7, 26.1 h？1） and characterized by means of N2 adsorption-desorption, NH3-TPD, XRD, TGA and SEM techniques. According to the experimental results, the catalysts prepared using sol-gel method in non-aqueous medium showed better performance compared with those prepared by other methods.

关键词： γ-Al2O3 sol-gel precipitation methanol dehydration dimethyl ether

CFD-DEM simulation of the hole cleaning process in a deviated well drilling： The effects of particle shape

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Particuology 2016年第2期14卷 72-82页

作者： Siamak Akhshik Mehdi Behzad majid Rajabi Department of Mechanical Engineering Sharif University of Technology Azadi Avenue Tehran Iran School of Mechanical Engineering lran University of Science and Technology Narmak Tehran Iran

We investigate the effect of particle shape on the transportation mechanism in well-drilling using a three-dimensional model that couples computational fluid dynamics （CFD） with the discrete element method （DEM）. This numerical method allows us to incorporate the fluid-particle interactions （drag force, contact force, Saffman lift force, Magnus lift force, buoyancy force） using momentum exchange and the non-Newtonian behavior of the fluid. The interactions of particle-particle, particle-wall, and particle-drill pipe are taken into account with the Hertz-Mindlin model. We compare the transport of spheres with non-spherical particles （non-smooth sphere, disc, and cubic） constructed via the multi- sphere method for a range of fluid inlet velocities and drill pipe inclination angles. The simulations are carried out for laboratory-scale drilling configurations. Our results demonstrate good agreement with published experimental data. We evaluate the fluid-particle flow patterns, the particle velocities, and the particle concentration profiles. The results reveal that particle sphericity plays a major role in the fluid-solid interaction. The traditional assumption of an ideal spherical particle may cause inaccurate results.

关键词： CFD-DEM method Deviated well drilling Particles transport Two-way coupling scheme Particle-fluid Interaction

Spin and pseudospin symmetric Dirac particles in the field of Tietz-Hua potential including Coulomb tensor interaction

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Chinese Physics B 2013年第9期22卷 233-244页

作者： Sameer M. Ikhdair majid Hamzavi Department of Physics Faculty of ScienceAn-Najah National UniversityNew CampusJunaidNablusWest BankPalestine Department of Electrical and Electronic Engineering Near East University Department of Science and Engineering Abhar BranchIslamic Azad University

Approximate analytical solutions of the Dirac equation for Tietz-Hua （TH） potential including Coulomb-like tensor （CLT） potential with arbitrary spin-orbit quantum number K are obtained within the Pekeris approximation scheme to deal with the spin-orbit coupling terms K（K± 1）r^-2. Under the exact spin and pseudospin symmetric limitation, bound state energy eigenvalues and associated unnormalized two-component wave functions of the Dirac particle in the field of both attractive and repulsive TH potential with tensor potential are found using the parametric Nikiforov-Uvarov （NU） method. The cases of the Morse oscillator with tensor potential, the generalized Morse oscillator with tensor potential, and the non-relativistic limits have been investigated.

关键词： Dirac equation Tietz-Hua (TH) potential Coulomb-like tensor (CLT) potential generalizedMorse potential

Effects of TiO_2 nanoparticles on the aquatic plant Spirodela polyrrhiza: Evaluation of growth parameters, pigment contents and antioxidant enzyme activities

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Journal of Environmental Sciences 2018年第2期30卷 130-138页

作者： Ali Movafeghi Alireza Khataee Mahboubeh abedi Roshanak Tarrahi Mohammadreza Dadpour Fatemeh Vafaei Department of Plant Biology Faculty of Natural Sciences University of Tabriz Research Laboratory of Advanced Water and Wastewater Treatment Processes Department of Applied Chemistry Faculty of ChemistryUniversity of Tabriz Department of Materials Science and Nanotechnology Near East University Department of Horticultural Science Faculty of Agriculture University of Tabriz

Plants are essential components of all ecosystems and play a critical role in environmental fate of nanoparticles. However, the toxicological impacts of nanoparticles on plants are not well documented. Titanium dioxide nanoparticles（TiO2-NPs） are produced worldwide in large quantities for a wide range of purposes. In the present study, the uptake of TiO2-NPs by the aquatic plant Spirodela polyrrhiza and the consequent effects on the plant were ***, structural and morphological characteristics of the used TiO2-NPs were determined using XRD, SEM, TEM and BET techniques. As a result, an anatase structure with the average crystalline size of 8 nm was confirmed for the synthesized TiO2-NPs. Subsequently, entrance of TiO2-NPSto plant roots was verified by fluorescence microscopic images. Activity of a number of antioxidant enzymes, as well as, changes in growth parameters and photosynthetic pigment contents as physiological indices were assessed to investigate the effects of TiO2-NPs on S. polyrrhiza. The increasing concentration of TiO2-NPs led to the significant decrease in all of the growth parameters and changes in antioxidant enzyme activities. The activity of superoxide dismutase enhanced significantly by the increasing concentration of TiO2-NPs. Enhancement of superoxide dismutase activity could be explained as promoting antioxidant system to scavenging the reactive oxygen species. In contrast, the activity of peroxidase was notably decreased in the treated plants. Reduced peroxidase activity could be attributed to either direct effect of these particles on the molecular structure of the enzyme or plant defense system damage due to reactive oxygen species.

关键词： TiO2 nanoparticles Spirodela polyrrhiza Growth parameters Antioxidant enzymes Pigment contents

Influence of B source materials on the synthesis of TiB_2-Al_2O_3 nanocomposite powders by mechanical alloying

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International Journal of Minerals,Metallurgy and Materials 2013年第12期20卷 1214-1220页

作者： majid Abdellahi Javad Heidari Rahman Sabouhi Materials Engineering Department Islamic Azad University

An Al2O3-TiB2 nanocomposite was successfully synthesized by ball milling of Al, TiO2 and two B source materials of B2O3 （system （1）） and H3BO3 （system （2））. Phase identification of the milled samples was examined by Xray diffraction. The morphology and microstructure of the milled powders were monitored by scanning electron microscopy and transmission electron microscopy. It was found that the formation of this composite was completed after 15 and 30 h of milling time in systems （1） and （2）, respectively. More milling energy was required for the formation of this composite in system （2） due to the lubricant properties of HaBO3 and also its decomposition to HBO2 and B2O3 during milling. On the basis of X-ray diffraction patterns and thermodynamic calculations, this composite was formed by highly exothermic mechanically induced self-sustaining reactions （MSR） in both systems. The MSR mode took place around 9 h and 25 h of milling in systems （1） and （2）, respectively. At the end of milling （15 h for system （1） and 30 h for system （2）） the grain size of about 35-50 nm was obtained in both systems.

关键词： nanocomposites powders alumina titanium diboride mechanical alloying

Effects of external fields on a two-dimensional Klein-Gordon particle under pseudo-harmonic oscillator interaction

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Chinese Physics B 2012年第11期21卷 68-73页

作者： Sameer M.Ikhdair majid Hamzavi Physics Department Near East University Department of Basic Sciences Shahrood BranchIslamic Azad University

We study the effects of the perpendicular magnetic and Aharonov-Bohm （AB） flux fields on the energy levels of a two-dimensional （2D） Klein Gordon （KG） particle subjected to an equal scalar and vector pseudo-harmonic oscillator （PHO）. We calculate the exact energy eigenvalues and normalized wave functions in terms of chemical potential param- eter, magnetic field strength, AB flux field, and magnetic quantum number by means of the Nikiforov Uvarov （NU） method. The non-relativistic limit, PHO, and harmonic oscillator solutions in the existence and absence of external fields are also obtained.

关键词： Klein-Gordon equation two-dimensional pseudo-harmonic oscillator (PHO) potential,magnetic and Aharonov-Bohm (AB) flux fields Nikiforov-Uvarov method

Multi-objective optimization of molten carbonate fuel cell system for reducing CO2 emission from exhaust gases

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Frontiers in Energy 2015年第1期9卷 106-114页

作者： Ramin ROSHANDEL majid ASTANEHI Farzin GOLZAR Department of Energy Engineering Sharif University of TechnologyTehran 14565114 Iran

The aim of this paper is to investigate the implementation of a molten carbonate fuel cell （MCFC） as a CO2 separator. By applying multi-objective optimization （MOO） using the genetic algorithm, the optimal values of operating load and the corresponding values of objective functions are obtained. Objective functions are minimiza- tion of the cost of electricity （COE） and minimization of CO2 emission rate. CO2 tax that is accounted as the pollution-related cost, transforming the environmental objective to the cost function. The results show that the MCFC stack which is fed by the syngas and gas turbine exhaust, not only reduces CO2 emission rate, but also produces electricity and reduces environmental cost of the system.

关键词： molten carbonate fuel cell (MCFC) multi-objective optimization (MOO) Pareto curve geneticalgorithm CO2 separation

Fouling of WO3 nanoparticle-incorporated PSf membranes in ultrafiltration of landfill leachate and dairy a combined wastewaters： An investigation using model

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Chinese Journal of Chemical Engineering 2017年第6期25卷 741-751页

作者： majid Peyravi Mohsen Jahanshahi Soodabeh Khalili Nanoenvironment Research Group Nanotechnology Institute Faculty of Chemical Engineering Babol Noshirvani University of Technolog~ Babol lran

As fouling has always been a major drawback of membrane technology, qualitative and quantitative understanding of membrane fouling mechanisms therefore becomes vital in order to help push membrane separation technologies forward. In this study, firstly, self-cleaning Polysulfone(PSf) membranes were synthesized by incorporation of WO_3nanoparticles(0–2 wt%) and subsequent UV irradiation for efficient ultrafiltration(UF)of landfill leachate and dairy wastewater. The membrane surface properties were characterized by scanning electron microscopy(SEM) and contact angle analysis. It was found that UV-irradiated membranes exhibited higher percent COD removals due to the hydrophilicity and photocatalytic properties of nano-WO_3. Subsequently, in order to analyze the fouling behavior of the membranes, a set of experimental data from cross-flow ultrafiltration of municipal landfill leachate and industrial dairy wastewater at 25 °C was obtained. A new model of membrane fouling was proposed based on a resistance in series concept and was fitted well with all experimental data *** all relative errors of prediction provided by the proposed model were less than 2.5%. In addition, it was revealed that this newly-developed model exhibited smooth transition between the common successive twostep pore blockage-cake filtration phenomena and thus eliminates the need to use separate equations for different mechanisms.

关键词： Fouling model Leachate wastewater Ultrafiltration Whey wastewater Chemical oxygen demand

A review on first principles based studies for improvement of cathode material of lithium ion batteries

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Journal of Energy Chemistry 2018年第1期27卷 219-237页

作者： Arslan Ullah Abdul majid Naema Rani Department of Physics.University of Cujrat.50700 Gujrat Pakistan Office of Research Innovation and CommercializationUniversity of GujratGujratPakistan

Lithium ion batteries（LIBs） are currently best energy storage devices providing rechargeable electrical storage to wide variety of applications – from portable electronics to automobiles. Though, these batteries are fully adopted, widely used and commercialized, but researchers are still extensively working on their constituent materials and developing technology to improve their performance. A major part of related research activities is devoted to the electrode of the battery for improvement in its performance thereby addressing issues like safety, lifetime, specific capacity, energy density and most importantly abundance and cost. There are number of cathode materials that have been proposed and tested at laboratory scale and subsequently utilized in commercialized batteries ever since the appearance of LIBs. Owing to the availability of improved computational resources in the last decade, first principles calculation has become a reliable tool and played a vital role to predict the material properties of electrodes prior to their experimental analysis. This review gives a comprehensive insight and thorough analysis of the global research efforts related to the cathode materials based on first principles framework, sheds light on current status of knowledge and explores the ways forward.

关键词： Lithium ion batteries Electrodes First principles methods

Effect of inertia nonlinearity on dynamic response of an asymmetric building equipped with tuned mass dampers

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Earthquake Engineering and Engineering Vibration 2020年第2期19卷 499-513页

作者： Hassan Rezazadeh Fereidoun Amini majid Amin Afshar School of Civil Engineering Iran University of Science and TechnologyP.O.Box 16765-163TehranIran Department of Technology and Engineering Imam Khomeini International University NorouzianP.O.Box 34149-16818QazvinIran

This study investigates the effect of nonlinear inertia on the dynamic response of an asymmetric building equipped with Tuned Mass Dampers(TMDs).In the field of structural engineering,many researchers have developed models to study the behavior of nonlinear TMDs,but the effect of nonlinear inertia has not received as much attention for asymmetric *** consider nonlinear inertia,the equations of motion are derived in a local rotary coordinates *** displacements and rotations of the modeled building and TMDs are defined by five-degree-of-freedom(5-DOFs).The equations of motion are derived by using the Lagrangian *** in the proposed nonlinear model,the equations of motion are different from a conventional linear *** order to compare the response of the proposed nonlinear model and a conventional linear model,numerical examples are presented and the response of the modeled buildings are derived under harmonic and earthquake *** is shown that if the nonlinear inertia is considered,the response of the modeled structures changes and the conventional linear approach cannot adequately model the dynamic behavior of the asymmetric buildings which are equipped with TMDs.

关键词： Nonlinear inertia tuned mass damper asymmetric buildings harmonic excitation seismic excitation