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Carbothermic Reduction of Zinc Oxide Concentrate by Microwave

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Journal of Materials Science & Technology 2005年第5期21卷 724-728页

作者： ali Saidi kamran Azari Department of Materials Engineering Isfahan University of TechnologyIsfahan IranNaghsh-e-Jahan Steel Research Institute Isfahan Science and Technology Town IsfahanIran

Industrial application of microwave, as a heating source for material processing, was reviewed. The feasibility of carbothermic reduction of zinc oxide concentrate, as well as the effect of operating parameters was investigated, using a home style microwave oven at 2.45 GHz. Zinc oxide concentrate does not effectively absorb microwave energy, while any source of carbon, which is used as the reduction agent, absorbs microwave energy very well. In this respect coke breeze was found to be the best, and thus, coke was used both as the reducing agent and the absorbent of microwave energy. It was also found that any increase in the carbon content and size, increases the reduction rate. Increasing the microwave power and the size of the sample could also increase the reduction rate. Further investigation shows that when zinc oxide is exposed to the microwave for some time, the rate of the reduction by conventional method increases.

关键词： Microwave Zinc oxide Reduction

Hot Ductility of Severe Plastic Deformed AA6061 Aluminum Alloy

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Acta Metallurgica Sinica(English Letters) 2015年第3期28卷 322-330页

作者： ali Akbar Khamei kamran Dehghani Mining and Metallurgical Engineering Department Amirkabir University of Technology

The hot ductility of 6061 aluminum alloy,which was subjected to two different severe plastic deformations（SPD）,was studied at different temperatures and strain *** tensile tests were carried out at the temperature range of 300-500 ℃ and at the strain rates of 0.0005-0.01 s^（-1）.The microstructure evolution was characterized using optical microscopy,transmission electron microscopy and X-ray diffraction *** influences of the microstructure after SPD,thermomechanical parameters（temperature and strain rate） and specimen size on the hot formability of this alloy were then *** results show that a decrease in grains/subgrains exhibited significant effect on the hot ductility of SPDed *** constitutive equations were then developed to model the hot formability of the studied *** developed model can be represented by Zener-Hollomon parameter in a hyperbolic sinusoidal equation *** the changes of elongation to failure and Zener-Hollomon parameter indicate that the hot ductility of the alloy is more sensitive to the temperature rather than to the strain *** uniform elongation is independent of the specimen size,but the postnecking elongation increases dramatically as the ratio of l/A^（1/2） decreases.

关键词： Al-Mg-Si alloy Deformation behavior Equal channel angular pressing(ECAP) Rolling Hot tensile deformation

Degradation of a discrete infilled joint shear strength subjected to repeated blast-induced vibrations

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International Journal of Mining Science and Technology 2018年第4期28卷 560-570页

作者： Siamaki ali Esmaieli kamran Mohanty Bibhu Lassonde Institute of Mining University of Toronto

This paper presents the results of a series of numerical modeling experiments aimed at quantifying blast- induced degradation of shear strength of discontinuities. Near-field vibration history of a single-row pro- duction blast in a. limestone quarry was used as input to the nu .merical model. For this. purpose, two rock blocks, representing a stiff massive sulfide rock and a weaker limestone rock, were simulated using the 2D Particle Flow Code （PFC2D）. Rock mass conta!ning a single inclined joint was modeled as Mohr- Coulomb. The results show that the crack generation rate is increased in both samples after repetitive vibration loading. Joint shear strength degradation rate in !he stiffer massive sulfide rock sample is higher than the softer limestone rock, which is attributed to the higher seismic impedance mismatch. The results show that even low-amplitude blasting vibrations （〈80 mm/s）, when repeated as in multi-hole blasts, can significantly degrade joint shear strength in the nearby pit walls.

关键词： Blasting Vibration PFC2D Discontinuity Rock Degradation

Evaluation the Properties of Polycaprolactone/Fluorapatite Nano-biocomposite

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Journal of Bionic Engineering 2022年第1期19卷 179-187页

作者： Mojtaba Momeni kamran Amini ali Heidari Mohammad Khodaei Department of Mechanical Engineering Khomeinishahr BranchIslamic Azad UniversityKhomeinishahr84181-48499IsfahanIran Center for Advanced Engineering Research Majlesi BranchIslamic Azad University86316-56451IsfahanIran Materials Engineering Group Golpayegan College of EngineeringIsfahan University of Technology87717-67498GolpayeganIran

In this study,nano-biocomposites of polycaprolactone(PCL)as the matrix and different amounts of nanofluorapatite(nFA)(0,10,20 and 30 wt.%)as the reinforcement were prepared for possible scaffold fabrication using the fused filament fabrication(FFF)3D *** Emission Scanning Electron Microscopy(FE-SEM)and Energy Dispersive Spectroscopy(EDS)showed that nFA particles were well distributed in the PCL matrix.X-ray diffraction analysis(XRD)and Fourier Transform Infrared Spectroscopy(FTIR)depicted no chemical interaction between the elements of the *** Scanning Calorimetric(DSC)analysis was then used to assess the thermal properties of the composites,suggesting that this could be due to the amorphous phase formation of the intermolecular hydrogen bonds between PCL and nFA,resulting in the suppression of PCL *** results of mechanical characterization also showed that the addition of nFA up to 20 wt.%to the PCL increased the tensile and yield strength,as well as reducing the elongation at both yield and failure points and increasing the Young *** best mechanical properties were obtained for the PCL/20nFA *** strength and Young modulus were increased by 30%and 179%,respectively;meanwhile,elongation of PCL/20nFA was decreased by 70%,as compared to the naked *** changes could be attributed to the better distribution of the nFA filler in the PCL *** to the obtained results,PCL/20nFA could be regarded as a good composite in terms of the mechanical properties for the regeneration of the bone tissue.

关键词： Nano-biocomposite Polycaprolactone Fluorapatite Bone tissue engineering Mechanical properties

Analytical model of sound transmission through laminated composite cylindrical shells considering transverse shear deformation

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Applied Mathematics and Mechanics(English Edition) 2008年第9期29卷 1165-1177页

作者： kamran Daneshjou ali Nouri Roohollah Talebitooti Department of Mechanical Engineering Iran University of Science and TechnologyNarmak

Composite structures are often used in the aerospace industry due to the advantages offered by a high strength to weight ratio. Sound transmission through an infinite laminated composite cylindrical shell is studied in the context of the transmission of airborne sound into the aircraft interior. The shell is immersed in an external fluid medium and contains internal fluid. Airflow in the external fluid medium moves with a constant velocity. An exact solution is obtained by simultaneously solving the first-order shear deformation theory （FSDT） of a laminated composite shell and the acoustic wave equations. Transmission losses （TL） obtained from numerical solutions are compared with those of other authors. The effects of structural properties and flight conditions on TL are studied for a range of values, especially, the Mach number, stack sequences, and the angle of warp. Additionally, comparisons of the transmission losses are made between the classical thin shell theory （CST） and FSDT for laminated composite and isotropic cylindrical shells.

关键词： plane wave transmission loss laminated composite shell first-order

Effect of deep cryogenic treatment on the properties of 80CrMo12 5 tool steel

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International Journal of Minerals,Metallurgy and Materials 2012年第1期19卷 30-37页

作者： kamran Amini Said Nategh ali Shafyei Ahmad Rezaeian Department of Materials Engineering Majlesi Branch Islamic Azad University Department of Materials Engineering Science and Research Branch Islamic Azad University Department of Materials Engineering Isfahan University of Technology

The effect of deep cryogenic treatment on the mechanical properties of 80CrMo 12 5 tool steel was investigated. Moreover, the effects of stabilization （holding at room temperature for some periods before deep cryogenic treatment） and tempering before deep cryogenic treatment were studied. The results show that deep cryogenic treatment can eliminate the retained austenite, making a better carbide distribu- tion and a higher carbide amount. As a result, a remarkable improvement in wear resistance of cryogenically treated specimens is observed. Moreover, the ultimate tensile strength increases, and the toughness of the sample decreases. It is also found that both stabilization and tem- pering before deep cryogenic treatment decrease the wear resistance, hardness, and carbides homogeneity compared to the deep cryogeni- cally treated samples. It is concluded that deep cryogenic treatment should be performed without any delay on samples after quenching to reach the highest wear resistance and hardness.

关键词： tool steel cryogenic treatment stabilization wear resistance tensile strength hardness carbides

Route Effect on Equal Channel Angular Pressing of Copper Tube

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 95-100页

作者： Faramarz Djavanroodi ali Asghar Zolfaghari Mahmoud Ebrahimi kamran Nikbin Department of Mechanical Engineering Imperial College Mechanical Engineering Department Iran University of Science and Technology

A new technique to produce ultra-fine grained tubular specimen has been proposed, and the experiments have been performed using equal channel angular pressing （ECAP） with an angle of 90 between two intersecting channels and also the use of rubber pad as a mandrel during process. Commercial purity copper tubes have been pressed up to three passes through four different fundamental routes （A, BA, Bc, and C） directions of which are identified in the text below. The influence of each route on the value, distribution, and homogeneity of hardness has been investigated by applying Vickers micro-hardness measurements at various locations of the tube＇s transverse planes. Significant enhancement of the hardness is observed after the first pass ECAP. Also, routes C and Bc show, respectively, better average hardness magnitude and hardness distribution uniformity. In addition, the results indicate that there is about 50% and 62% reduction of the grain size, compared to the annealed condition, following ECAP process of the copper tube sample after the first and the third pass via route Bc.

关键词： Severe plastic deformation (SPD) Equal channel angular pressing (ECAP) Tube Route Hardness

Numerical assessment of the mechanical stability in vertical,directional and horizontal wellbores

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International Journal of Mining Science and Technology 2013年第6期23卷 937-942页

作者： kamran Goshtasbi Ayub Elyasi ali Naeimipour Department of Mining Engineering Tarbiat Modares University School of Energy and Mineral Engineering Pennsylvania State University

In this research the stability of wellbore is evaluated in seven different stress regimes and diverse orientations using FLAC3D *** normalized yielded zone area(NYZA.i.e.,the ratio of surrounding yielded cross-sectional area to initial area of wellbore)is determined for different mud pressures as well as diverse orientations of *** means of MATLAB software the best curve is fitted to the recorded points and then the optimized mud pressure is calculated using these *** optimized orientation is selected considering these *** the mud pressure resulted from this method was compared with the mud pressure obtained from the Mogi-Coulomb criterion and then with the fields *** minimum allowable mud pressure obtained from the NYZA criterion is close to actual data and the value obtained from the Mogi-Coulomb ***,the NYZA is considered to be an appropriate criterion for wellbore stability analysis.

关键词： NYZA Mud pressure Optimum orientation Stress regime

Algebraic Properties for Molecular Structure of Magnesium Iodide

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1131-1146页

作者： ali N.A.Koam ali Ahmad Muhammad Azeem Muhammad kamran Siddiqui Department of Mathematics College of ScienceNew CampusJazan UniversityJazanSaudi Arabia College of Computer Science and Information Technology Jazan UniversityJazanSaudi Arabia Department of Mathematics Riphah Institute of Computing and Applied SciencesRiphah International UniversityLahorePakistan Department of Mathematics COMSATS University IslamabadLahorePakistan

As an inorganic chemical,magnesium iodide has a significant crystalline *** is a complex and multifunctional substance that has the potential to be used in a wide range of medical *** graph theory,on the other hand,provides a sufficient and cost-effective method of investigating chemical structures and networks.M-polynomial is a relatively new method for studying chemical networks and structures in molecular graph *** displays numerical descriptors in algebraic form and highlights molecular features in the form of a polynomial *** present a polynomials display of magnesium iodide structure and calculate several M-polynomials in this paper,particularly the M-polynomials of the augmented Zagreb index,inverse sum index,hyper Zagreb index and for the symmetric division index.

关键词： Magnesium iodide M-polynomials algebraic properties of magnesium iodide algebraic formation of numerics of magnesium iodide