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International Journal of Minerals,Metallurgy and Materials 2012年第10期19卷 908-914页

作者： Masoud jabbari Parviz Davami Naser Vara.r.m Department of Mechanical Engineering Technical University of DenmarkKgs.Lyngby 2800Denmark Department of Materials Science and Engineering Sharif University of TechnologyTehran 11365Iran

To predict the amount of different phases in gray cast iron by a finite difference model （FDM） on the basis of cooling rate （r）, the volume fractions of total y phase, graphite, and cementite were calculated. The results of phase composition were evaluated to find a proper correlation with cooling rate. More trials were ca.r.ed out to find a good correlation between the hardness and phase composition. New proposed formulas show that the hardness of gray cast iron decreases as the amount of graphite phase increases, and increases as the amount of cementite inereases. The,qe fnrrnulas are develoned to correlate the nhase volume fraction to hardness. The results are compared with exverimental data and show reasonable a.r.ement.

关键词： cast iron cooling microstructure mechanical properties finite difference method

Corrosion and corrosion-fatigue behavior of magnesium metal ma.r.x composites for bio-implant applications:a.r.view

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Journal of Magnesium and Alloys 2023年第4期11卷 1125-1161页

作者： Hassan Delavar Amirhossein jabbari Mostahsan Hamdy Ibrahim School of Mechanical Engineering Iran University of Science and TechnologyTehranIran Department of Mechanical Engineering Sharif University of TechnologyTehranIran Mechanical Engineering Department University of Tennessee at ChattanoogaChattanoogaTN 37403USA

recently,the topic of bioresorbable metals,with much focus on magnesium for bone implant applications,has been an area of considerable ***,it could be argued that magnesium is the most promising biodegradable material currently being studied for use as an orthopedic skeletal fixation and joint replacement ***,the fast degradation rate of magnesium-based materials in the physiological environment negatively affects their mechanical integrity and hence limits their biomedical *** most critical conditions may occur when the implant is subjected to a corrosive physiological environment and a fluctuating load during daily ***,numerous studies have been published on the synthesis,alloying,and coating of magnesium to control degradation rate and increase strength and *** the materials and strategies employed to achieve these goals,magnesium-based biocomposites have exhibited superior mechanical properties and acceptable ***,there is a lack of understanding of their corrosion and corrosion-fatigue *** understanding is necessary to qualify these new materials for various bio-implant *** this end,this paper reviews the recent advances in the corrosion and corrosion-fatigue behavior of magnesium-based *** also provides a comprehensive discussion of different factors that influence the biocompatibility,corrosion,fatigue,and corrosion-fatigue of magnesium-based biocomposites as potential implant *** study emphasizes that despite the abundance of various studies on the corrosion behavior of magnesium-based biocomposites,there is an imperative need for more fatigue and corrosion-fatigue studies.

关键词： Magnesium biocomposites Biodegradable implants Corrosion Fatigue Corrosion-fatigue

relationship Between Land Use Changes and the Production of Dust Sources in Kermanshah Province,Iran

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Chinese Geographical Science 2021年第6期31卷 1057-1069页

作者： AHMADI-MOLAVErDI Majid jabbari Iraj FATHNIA Amanollah Department of Geography Faculty of Literature and HumanitiesRazi UniversityKermanshah***Iran

recognizing land use changes(LUC)and evaluating their relationship with producing dust sources are considered effective to manage the *** Kermanshah Province,Iran as study area,dusty days from 2008 to 2015 were selected and dust sources were identified applying thermal-infrared dust index(TDI),hybrid single-particle la.r.ngian integrated trajectory(HYSPLIT),false color composite(FCC)and true color composite(TCC)of MODerate resolution Imaging Spectroradiometer(MODIS)***,the land use change map was produced using Landsat images in 2000 and ***,the distribution and frequency of the sources in each land-use change class and important dust production areas were ***,two non-parametric tests including Chisquare and Kruskal-Wallis were applied to examine the relationship between LUC and dust *** indicated that the distribution of dust sources was not identical in the study area,and the sources were mainly generated in the areas where land-use change had *** fact,different classes of LUC have different contributions to dust production,and the highest contribution refers to the deflation in gentle slope areas and lowlands where the rangeland has been converted into a.r.culture *** findings from this study are useful to manage and control dust in the identified sources.

关键词： dust source hybrid single-particle la.r.ngian integrated trajectory(HYSPLIT) land use change(LUC) MODerate resolution imaging spectroradiometer(MODIS) thermal-infrared dust index(TDI) Kermanshah Province,Iran Iran

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

Backward bifurcation in a fractional-order and two-patch model of tuberculosis epidemic with incomplete treatment

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International Journal of Biomathematics 2021年第2期14卷 139-167页

作者： Mohsen Jafari Hossein Kheiri Azizeh jabbari Faculty of Mathematical Sciences University of TabrizTabrizIran Marand Faculty of Engineering University of TabrizTabrizIran

In this paper,we consider a tuberculosis model with incomplete treatment and extend the model to a Caputo fractional-order and two-patch version with exogenous re-infection among the treated individuals,in which only susceptible individuals can travel freely between the *** model has multiple *** determine conditions that lead to the appearance of a backward *** results show that the TB model can have exogenous reinfection among the treated individuals and,at the same time,does not exhibit backward ***,conditions that lead to the global asymptotic stability of the disease-free equilibrium are *** case without reinfection,the model has four *** this case,the global asymptotic stability of the equilibria is established using the Lyapunov function theory together with the LaSalle invariance principle for fractional differential equations(FDEs).Numerical simulations confirm the validity of the theoretical results.

关键词： Patch models fractional-order derivatives global stability backward bifurcation.

Effects of cold rolling on the microstructure and mechanical properties of Fe-Ni-Mn-Mo-Ti-Cr maraging steels

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 557-561页

作者： Abbas Mahmudi Syamak Hossein Nedjad Mir Masud jabbari Behnam Young researchers Club Islamic Azad University (Ahar Branch)54516 AharTabrizIran Faculty of Materials Engineering Sahand University of TechnologyTabriz 51335-1996Iran Department of Materials Science and Engineering Sharif University of TechnologyTehran 11365Iran

Effects of cold rolling on the microstructure and mechanical properties of Fe-Ni-Mn-Mo-Ti-Cr maraging steels were *** investigate the microstructure and mechanical properties,optical microscopy,scanning electron microscopy,X-ray diffraction,tensile test,and hardness test were *** results show that the solution-annealing treatment in the cold-rolled steel redounds to the formation of sub-microcrystalline Fe2（Mo,Ti） Laves phase particles,which are stable at high *** secondary Laves phase particles prevent from recrystallization at high temperatures and correspond to semi-brittle fracture in the subsequent aging treatment.

关键词： maraging steel cold rolling age hardening Laves-phase microstructure mechanical properties

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

Material and regenerative properties of an osteon-mimetic cortical bone-like scaffold

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regenerative Biomaterials 2019年第2期6卷 89-98页

作者： Danial Barati Ozan Karaman Seyedsina Moeinzadeh Safaa Kader Esmaiel jabbari Biomimetic Materials and Tissue Engineering Laboratory Department of Chemical EngineeringUniversity of South CarolinaColumbiaSC 29208USA Department of Chemistry and Biochemistry University of South CarolinaColumbiaSC 29208USA Department of Biomedical Engineering Izmir Katip Celebi UniversityIzmir 35620Turkey

The objective of this work was to fa.r.cate a.r.gid,resorbable and osteoconductive scaffold by mimicking the hierarchical structure of the cortical *** peptide-functionalize nanofiber microsheets were generated with calcium phosphate(CaP)content similar to that of the natural cortical ***,the CaP-rich fibrous microsheets were wrapped around a microneedle to form a laminated microtube mimicking the structure of an ***,a set of the osteon-mimetic microtubes were assembled around a solid rod and the assembly was annealed to fuse the microtubes and form a ***,an a.r.y of circular microholes were drilled on the outer surface of the shell to generate a cortical bone-like scaffold with an interconnected network of Haversian-and Volkmann-like *** CaP content,porosity and density of the bone-mimetic microsheets were 240 wt%,8%and 1.9 g/ml,respectively,which were close to that of natural cortical *** interconnected network of microcanals in the fused microtubes increased permeability of a model protein in the *** cortical scaffold induced osteogenesis and vasculogenesis in the absence of bone morphogenetic proteins upon seeding with human mesenchymal stem cells and endothelial colony-forming *** localized and timed-release of morphogenetic factors significantly increased the extent of osteogenic and vasculogenic differentiation of human mesenchymal stem cells and endothelial colony-forming cells in the cortical *** cortical bonemimetic nature of the cellular construct provided balanced rigidity,resorption rate,osteoconductivity and nutrient diffusivity to support vascularization and osteogenesis.

关键词： bone regeneration cortical bone-like osteon-mimetic calcium phosphate nucleated nanofiber microsheet vascularized osteogenesis

Hydraulic and mechanical properties of wax-coated sands

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Journal of Central South University 2013年第12期20卷 3667-3675页

作者： Jesmani Mehrab Bardet Jean-Pierre jabbari Nima Kamalzare Mehrad Department of Civil Engineering Imam Khomeini International University Sonny Astani Department of Civil and Environmental Engineering Viterbi School of Engineering Department of Civil and Environmental Engineering Rensselaer Polytechnic Institute

Wax-coated sands are a new category of synthetic soils, which are gradually becoming a.r.liable construction material. Because of their valuable drainage ability and mechanical properties, wax coated sandy soils are specifically applicable to pavement construction of horseracing tracks and sport fields. Although the mechanical and hydraulic properties of these synthetic soils are well-proven, there is still a lack of studies on how the soil samples behave differently when mixing with different wax fractions. Adding the wax affects permeability and compressibility of pure sand. Intensity of influences is a function of weight percentage of wax that has been added, and other physical and environmental factors. The effects of wax content on hydraulic properties(permeability), and mechanical properties(stress strain behavior, compressibility) of sandy soils based on a series of experimental efforts were investigated. Obtained experimental results infer that increasing the amount of wax up to 6% causes an about 50% increase in permeability, mainly because of the significant effect of wax in lowering the friction along with covering and filling the angular parts of particles' surfaces and forming rounded particles. In addition, wax-coated sands show a 20% to 60% decrease in confined compression modulus compared to non wax-coated sands.

关键词： wax-coated sand confined compression coefficient permeability compressibility stress-strain behavior