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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

Nonlinear vibration of Timoshenko FG porous sandwich beams subjected to a harmonic axial load

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 649-662页

作者： Milad Lezgi Moein Zanjanchi Nikoo majid Ghadiri Department of Civil Engineering Sharif University of TechnologyTehran ***Iran Civil Engineering Department K.N.Toosi University of TechnologyTehran ***Iran Faculty of Engineering Department of MechanicsImam Khomeini International UniversityQazvin ***Iran

In this study,the instability and bifurcation diagrams of a functionally graded(FG)porous sandwich beam on an elastic,viscous foundation which is influenced by an axial load,are investigated with an analytical *** do so,the Timoshenko beam theory is utilized to take the shear deformations into account,and the nonlinear Von-Karman approach is adopted to acquire the equations of ***,to turn the partial differential equations(PDEs)into ordinary differential equations(ODEs)in the case of equations of motion,the method of Galerkin is employed,followed by the multiple time scale method to solve the resulting *** impact of parameters affecting the response of the beam,including the porosity distribution,porosity coefficient,temperature increments,slenderness,thickness,and damping ratios,are explicitly *** is found that the parameters mentioned above affect the bifurcation points and instability of the sandwich porous beams,some of which,including the effect of temperature and porosity distribution,are less noticeable.

关键词： sandwich beam Timoshenko beam parametric excitation bifurcation diagrams dynamic instability

Optimization of hydrothermal synthesis of H-ZSM-5 zeolite for dehydration of methanol to dimethyl ether using full factorial design

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Journal of Natural Gas Chemistry 2012年第3期21卷 344-351页

作者： Samaneh Hosseini majid Taghizadeh Ali Eliassi Chemical Engineering Department Babol University of TechnologyP.O.Box 484*** BabolIran Chemical Technologies Research Department Iranian Research Organization for Science and TechnologyTehranIran

H-ZSM-5 zeolite was synthesized by hydrothermal method. The effects of different synthesis parameters, such as hydrothermal crystallization temperature （170-190 ℃） and Si/A1 molar ratio （100-150）, on the catalytic performance of the dehydration of methanol to dimethyl ether （DME） over the synthesized H-ZSM-5 zeolite were studied. The catalysts were characterized by N2 adsorption-desorption, XRD, NH3-TPD, TGA/DTA, and SEM techniques. The full factorial design of experiments was applied to the synthesis of H-ZSM-5 zeolite and the effects of synthesis conditions and their interaction on the yield of DME as the response variable were determined. Analysis of variance showed that two variables and their interaction significantly affected the response. According to the experimental results, the optimized catalyst prepared at 170℃ with the Si/A1 molar ratio of 100 showed the best catalytic performance among the tested H-ZSM-5 zeolite.

关键词： full factorial design H-ZSM-5 synthesis methanol dehydration dimethyl ether

Lead removal from aqueous medium using fruit peels and polyaniline composites in aqueous and non-aqueous solvents in the presence of polyethylene glycol

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Chinese Journal of Chemical Engineering 2022年第4期35卷 253-259页

作者： Iman Farirzadeh majid Riahi Samani Davood Toghraie Department of Civil Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran Department of Mechanical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahrIran

In the present study,composites of Polyaniline and some fruit peels were synthesized in various conditions and used for lead removal from aqueous *** tests were conducted in batch mode using the most efficient adsorbent,and the effects of medium pH,initial lead concentration,contact time,adsorbent dosage,and adsorption isotherms were *** results showed that all composites were more efficient in lead removal compared to the fruit peels *** highest removal percentage was related to the composite of banana peel and Polyaniline that synthesized in the aqueous solution in the presence of 2 g·L^(-1) Poly ethylene *** composite showed 95.96%lead adsorption at pH=6,the contact time of 90 min,the initial lead concentration of 25 mg·L^(-1),and an adsorbent concentration of 8 g·L^(-1).Adsorption isotherm study showed that adsorption of lead by synthesized composite could be fitted by both Langmuir and Freundlich models,but the Langmuir model was more fitted than ***,some characteristics of the composites,such as chemical composition(XRD analysis),structure,and morphology(SEM analysis)and functional groups(FTIR analysis),were studied.

关键词： Adsorption Banana peel Composites Pollution Polyaniline

Preparation of 2-amino-5,7-dimethoxy-4-aryl/alkyl-4H-chromene-3-carbonitriles using Na_2O-Al_2O_3-P_2O_5 glass–ceramic system

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Chinese Chemical Letters 2015年第11期26卷 1385-1388页

作者： Saeid Jabbarzare majid Ghashang Advanced Materials Research Center Materials Engineering Department Najafabad Branch Islamic Azad University Department of Chemistry Faculty of Sciences Najafabad Branch Islamic Azad University

A highly efficient and environmentally benign protocol for the synthesis of 2-amino-5,7-dimethoxy-4- aryl/alkyl-4H-chromene-3-carbonitrile derivatives by one-pot three-component coupling reacting of aromatic aldehydes, malononitrile and 3,5-dimethoxy phenol under reflux condition has been developed in aqueous EtOH media using Na2O-Al2O3-P2O5 glass-ceramic system.

关键词： Na2O-Al2O3-P2O5 glass-ceramic system2-Amino-4H-chromene3 5-Dimethoxy phenol2-Amino- 5 7-dimethoxy-4-aryl/alkyl-4H-chromene-3-carbonitriles