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Transactions of Nonferrous Metals Society of China 2020年第5期30卷 1249-1266页

作者： M.DAREINI a.h.jabbari M.SEDIGhI School of Mechanical Engineering Iran University of Science and TechnologyNarmakTehran ***Iran

The effect of hot-forging process was investigated on microstructural and mechanical properties of AZ31 B alloy and AZ31 B/1.5 vol.%Al2 O3 nanocomposite under static and cycling loading. The as-cast alloy and composite were firstly subjected to a homogenization heat treatment at 450 ℃ and then an open-die forging at 450 ℃. The results indicated that the presence of reinforcing particles led to grain refinement and improvement of dynamic recrystallization. The forging process was more effective to eliminate the porosity in the cast alloy workpiece. Microhardness of the forged composite was increased by up to 80% and 16%, in comparison with those of the cast and forged alloy samples, respectively. Ultimate tensile strength and maximum tensile strain of the composite were improved by up to 45% and 23%, compared with those of the forged alloy in similar regions. These enhancements were respectively 50% and 37% in the compression test. The composite exhibited a fatigue life improvement in the region with low applied strain;however, a degradation was observed in the high applied strain region. Unlike AZ31 B samples, tensile, compressive and high cycle fatigue behaviors of the composite showed less sensitivity to the applied strain, which can be attributed to the amount of porosity in the samples before and after the hot-forging.

关键词： magnesium matrix nanocomposite AZ31B alloy nano-sized Al2O3 open-die hot-forging high cycle fatigue mechanical properties microstructural evolution

In vitro corrosion-fatigue behavior of biodegradable Mg/hA composite in simulated body fluid

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Journal of Magnesium and Alloys 2021年第6期9卷 2169-2184页

作者： E.Ghazizadeh a.h.jabbari M.Sedighi School of Mechanical Engineering Iran University of Science and TechnologyNarmakTehranIran

Magnesium and its composites as biodegradable materials offer especial capabilities to be used as bio-absorbable ***,their poor corrosion and fatigue properties in the physiological environment can restrict their *** this study,corrosion-fatigue tests have been performed on the extruded magnesium and magnesium/hydroxyapatite(Mg/hA)composites in a high cycle *** produce the composites,pure magnesium was reinforced by 2.5 wt.%and 5 wt.%of hydroxyapatite submicron particles using an electromagneticmechanical stirring method and hot extrusion *** experimental density measurement exhibits that the porosity increases in the extruded samples with more hydroxyapatite *** investigate the corrosion and corrosion-fatigue behavior of the specimens,simulated body fluid(SBF)was used during in vitro *** results of the potentiodynamic polarization corrosion test show that the composite with 2.5 wt.%of hydroxyapatite(Mg/2.5 wt.%hA)and the pure magnesium specimen exhibit the highest and the lowest corrosion resistance,*** the elemental mapping analysis of the corroded samples,this behavior could be due to the formation of strong phosphorus-calcium based layers on the composite *** results obtained from the mechanical tests indicate that Mg/5 wt.%hA offered the highest tensile and compressive yield strengths,as well as the most promising high cycle fatigue *** the corrosionfatigue test,the simultaneous effects of fatigue and corrosion damages led to a similar corrosion-fatigue behavior in both *** fracture surfaces of the corrosion-fatigue samples suggest that the cracks are initiated in the corroded regions of the samples surface,which reduces the crack initiation step and subsequently decreases the fatigue *** comparison with the pure magnesium,both composites exhibit more promising corrosion and corrosion-fatigue behaviors with a significant fatigue life improvement in the ph

关键词： Magnesium Magnesium/hydroxyapatite composite Corrosion Biodegradation high cycle fatigue Corrosion-fatigue

Dynamical analysis of the avian-human influenza epidemic model using multistage analytical method

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International Journal of Biomathematics 2016年第6期9卷 191-209页

作者： A. jabbari h. Kheiri A. Jodayree Akbarfam A. Bekir Department of Applied MathematicsUniversity of Tabriz 29 Bahman St. Tabriz Iran Mathematics and Computer Sciences DepartmentEskisehir Osmangazi University 26480 Eskisehir Turkey

In this paper, analytical result of avian-human influenza epidemic model has been inves- tigated by applying homotopy analysis method （hAM） and by expanding it to hybrid numeric-analytic method which is known as multistage hAM （MShAM）. hAM is an algorithm which gives us the approximate solution of the problem in an arrangement of time interims and by modifying it to multistage one. Some advantages such as flexibility of picking the auxiliary linear operator and the auxiliary parameter are emerged, that leads us to achieve some excellent results in this work. Furthermore, in this analyti- cal work, obtained results are compared and reported with numerical ones which were obtained previously from methods such as the Runge-Kutta （RK4） method.

关键词： Avian-human influenza epidemic model multistage homotopy analysismethod Runge-Kutta method.

A generalization of （G＇/G）-expansion method and its application to nonlinear reaction-diffusion equations arising in mathematical biology

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International Journal of Biomathematics 2014年第3期7卷 41-50页

作者： A. jabbari J. Manafian heris h. Kheiri A. Bekir Department of Applied Mathematics University of Tabriz 29 Bahman St. Tabriz-Iran Mathematics and Computer Sciences Department Eskisehir Osmangazi University 26480 Eskisehir Turkey

In this paper, by introducing a proper transformation, the （Gr/G）-expansion method is further extended into the nonlinear reaction diffusion equations in mathematical biology whose balancing numbers may be negative integer. As a result, hyperbolic function solutions and trigonometric function solutions with free parameters are obtained. When the parameters are taken as special values the solitary wave solutions and the periodic wave solutions are also derived from the traveling wave solutions. Moreover, it is observed that the suggested techniques is compatible of such problems.

关键词： Generalized (GI/G)-expansion method exact solutions nonlinear reaction-diffusion equations.

Some Notes on Amenability and Weak Amenability of Lau Product of Banach Algebras Defined by a Banach Algebra Morphism

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Acta Mathematica Sinica,English Series 2015年第9期31卷 1461-1474页

作者： Prakash A.DABhI Ali jabbari Kazem hAGhNEJAD AZAR Department of Mathematics Sardar Patel University Department of Mathematics Payame Noor University Department of Mathematics University of Mohaghegh Ardabili

Let A and B be Banach algebras and T ： B → A be a continuous homomorphism, n- weak amenability of the Banach algebra A ：X：T B （defined in Bade, W. G., Curtis, P. C., Dales, h. G.： Amenability and weak amenability for Beurling and Lipschitz algebras. Proc. London Math. Soc., 55（2）, 359-377 （1987）） is studied. The new version of a Banach algebra defined with a continuous homomorphism is introduced and Arens regularity and various notions of amenability of this algebra are studied.

关键词： Banach algebra Lau product amenability weak amenability

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机磨热加工法合成碳纳米管

新型炭材料 2009年第1期24卷 39-44页

作者： S. A. Manafi M. h. Amin M. R. Rahimipour E.Salahi A. Kazemzadeh Ceramic Department Materials and Energy Research Center P.O. Box 14155-4777 Tehran-Iran

机磨热加工法是批量制取碳纳米管(CNTs)的方法之一。在氩气氛中研磨鳞片石墨为无定形的纳米炭粉,而后在1350℃～1380℃下退火获得碳纳米管(CNTs)。用XRD,SEM,FE-TEM,hRTEM和拉曼光谱对纳米炭粉及CNTs进行表征。发现:CNTs具有不同的形貌... 详细信息

机磨热加工法是批量制取碳纳米管(CNTs)的方法之一。在氩气氛中研磨鳞片石墨为无定形的纳米炭粉,而后在1350℃～1380℃下退火获得碳纳米管(CNTs)。用XRD,SEM,FE-TEM,hRTEM和拉曼光谱对纳米炭粉及CNTs进行表征。发现:CNTs具有不同的形貌,长度约几毫米,直径为30nm～70nm。螺旋状多壁碳纳米管有高的长径比(～1000)和高的结晶度(ID/IG:～0.03)。

关键词：形貌 CNTs 机磨热加工 hRTEM