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Numerical Simulation of the Mechanical Properties of Sintered and Bonded Perforated Hollow Sphere Structures (PHSS)

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Journal of Materials Science & Technology 2010年第8期26卷 730-736页

作者： Andreas chsner Seyed mohammad hossein hosseini Markus Merkel Department of Applied Mechanics Technical University of Malaysia Centre for Mass and Mechanical Transport in Engineering Materials The University of Newcastle CallaghanNewSouth Wales 2308Australia Department of Mechanical Engineering University of Applied Sciences Aalen

This paper investigated the uniaxial mechanical properties of a new type of hollow sphere structures. For this new type, the sphere shell was perforated by several holes in order to open the inner sphere volume and surface. The mechanical properties, i.e. elastic properties and initial yield stress of perforated hollow sphere structures （PHSS） in a primitive cubic arrangement were numerically evaluated for different hole diameters and different joining techniques of the hollow spheres. The results are compared to classical configurations without perforation.

关键词： Mechanical properties Cellular material Porous structure Finite element method

Investigation of Hydrous Pyrolysis on Type-Ⅱ Kerogen-bearing Source Rocks from Iran and its Application in Geochemical and Kinetic Analyses of Hydrocarbon Products

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Acta Geologica Sinica(English Edition) 2021年第5期95卷 1736-1745页

作者： Shahryar KASHI mohammad hossein SABERI Faramarz HORMOZI Faculty of New Science and Technology Department of Petroleum EngineeringSemnan UniversitySemnan ***Iran Faculty of Chemical Petroleum and Gas EngineeringSemnan UniversitySemnan ***Iran

Hydrous pyrolysis(HP)practiced on type-Ⅱ kerogen-bearing oil shale samples from the Sargelu Formation in the Ghali-Kuh Area,western Iran,using a specially designed apparatus was performed at different temperatures(250-350℃),with hydrocarbon generation evaluated at each *** comparison,the samples subjected to Rock-Eval pyrolysis before proceeding to HP resulted in T_(max)=418℃,HI=102,and TOC=4.33%,indicating immaturity and hence remarkable hydrocarbon(especially oil)generation potential,making them appropriate for ***,the samples were deposited in a low-energy reductive marine environment,with maximum oil and gas generation(739 mg and 348 mg out of50 g of rock sample,respectively)observed at 330℃ and 350℃,*** oil generated at 330℃ was subjected to gas chromatography(GC)and isotopic analyses to assess hydrocarbon quality and *** hydrocarbon generation data was devised to estimate kinetic indices of the Arrhenius equation and to investigate the gas-oil ratio(GOR)and overall conversion *** on the producible hydrocarbon quantity and quality,the findings contribute to the economic assessment of oil shales across the study *** developed kinetic model indicates the history of hydrocarbon generation and organic matter(OM)maturity.

关键词： unconventional hydrocarbons oil shale hydrous pyrolysis organic matter maturity Arrhenius equation Sargelu Formation Lurestan province

Fabrication of Bulk (Fe,Cr)_3Al/Al_2O_3 Intermetallic Matrix Nanocomposite Through Mechanical Alloying and Sintering

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 911-919页

作者： Sayyed Erfan Aghili mohammad hossein Enayati Fathallah Karimzadeh Department of Materials Engineering Isfahan University of Technology

In the present study, （Fe,Cr）3Al/20 vol% A1203 nanocomposite was prepared through mechanochemical reactions during ball milling and successfully bulked using a combination of cold isostatic press and sintering at 1400℃ for 1 h. Two processing approaches were utilized to produce （Fe,Cr）3A1/A1203 nanocomposite： The first was milling of Fe, Cr, AI and Fe203, while the second one was milling of Fe, Cr, Al and Cr203, both in stoichiometric condition, to synthesize （Fe,Cr）3Al/20 vol% Al2O3. Structural changes of powder particles during mechanical alloying were studied by X-ray diffraction. The microstructure and the morphology of powder particles and bulk samples were also studied by scanning electron microscopy and transmission electron microscopy. Microstructural analysis showed that mechanochemical reactions took place during milling, and nanometric Al2O3 was uniformly distributed in the matrix. The results also showed that the second approach required a considerably higher milling time to produce （Fe,Cr）3Al/Al2O3 nanocomposite, as compared to the first one. For this reason, bulk samples were produced from the synthesized nanocomposite in the first approach. The microstructure of the sintered samples consisted of a network structure of （Fe,Cr）3Al and Al2O3 phases with superior mechanical properties.

关键词： Iron aluminide Mechanical alloying Nanocomposite Mechanochemical treatment

Influence of Specimen Geometry of Hot Torsion Test on Temperature Distribution During Reheating Treatment of API-X70

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Journal of Iron and Steel Research International 2010年第3期17卷 34-39页

作者： Bahman Mirzakhani Shahin Khoddam hossein Arabi mohammad Taghi Salehi Seyed hossein Seyedein mohammad Reza Aboutalebi Faculty of Engineering Arak University Department of Mechanical Engineering Monash UniversityClayton Campus Department of Materials and Metallurgical Engineering Iran University of Science and Technology

The commercial finite element package ANSYSTM was utilized for prediction of temperature distribution during reheating treatment of hot torsion test （HTT） samples with different geometries for API-X70 microalloyed steel. Simulation results show that an inappropriate choice of test specimen geometry and reheating conditions before deformation could lead to non-uniform temperature distribution within the gauge section of specimen. Therefore, assumptions of isothermal experimental conditions and zero temperature gradient within the specimen cross section appear unjustified and led to uncertainties of flow curve obtained. Recommendations on finding proper specimen geometry for reducing temperature gradient along the gauge part of specimen will be given to create homogeneous initial microstructure as much as possible before deformation in order to avoid uncertainty in consequent results of HTT.

关键词： hot torsion test simulation specimen geometry reheating treatment microalloyed steel

Toward Cloud Computing QoS Architecture:Analysis of Cloud Systems and Cloud Services

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IEEE/CAA Journal of Automatica Sinica 2017年第1期4卷 6-18页

作者： mohammad hossein Ghahramani MengChu Zhou Chi Tin Hon IEEE Institute of Systems Engineering Macao University of Science and Technology Helen and John C. Hartmann Department of Electrical and Computer Engineering New Jersey Institute of Technology School of Management Fudan University

Cloud can be defined as a new computing paradigm that provides scalable, on-demand, and virtualized resources for users. In this style of computing, users can access a shared pool of computing resources which are provisioned with minimal management efforts of users. Yet there are some obstacles and concerns about the use of clouds. Guaranteeing quality of service QoS by service providers can be regarded as one of the main concerns for companies tending to use it. Service provisioning in clouds is based on service level agreements representing a contract negotiated between users and providers. According to this contract, if a provider cannot satisfy its agreed application requirements, it should pay penalties as compensation. In this paper, we intend to carry out a comprehensive survey on the models proposed in literature with respect to the implementation principles to address the QoS guarantee issue. © 2014 Chinese Association of Automation.

关键词： Cloud computing Distributed computer systems System of systems Systems engineering Telecommunication services Web services

Corrosion Behavior and Biocompatibility of Hydroxyapatite Coating on H_2SO_4 Passivated 316L SS for Human Body Implant

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Acta Metallurgica Sinica(English Letters) 2013年第4期26卷 409-415页

作者： Ali Parsapour Saied Nouri Khorasani mohammad hossein Fathi Biomaterials Research Center Department of Chemical Engineering Isfahan University of Technology Department of Materials Engineering Isfahan University of Technology

The aim of this studies at simultaneous improvement of the corrosion behavior and biocompatibility of metallic implant and bone Osseointegration simultaneously. Stainless steel 316L （SS） was used as metallic substrate and after surface treatment with 15 vol.% sulfuric acid, it was coated with hydroxyapatite coating employing plasma - spraying process. Structure characterization techniques including XRD, SEM and EDX were also utilized to investigate the microstructure, morphology, and crystallinity of the coating. Electrochemical potentiodynamic tests were performed in two types of physiological solutions in order to determine and compare the corrosion resistance behavior of the coated and uncoated specimens as an indication of biocompatibility. The results indicate that the surface treatment and hydroxyapatite coating improve the corrosion resistance behavior of SS. The corrosion current density of the surface treated and the hydroxyapatite coated SS also decrease. These also show that surface treated and hydroxyapatite coated SS can be used as human body implants with the goals of corrosion resistance improvement （biocompatibility） and bone osseointegration.

关键词： Surface treatment Hydroxyapatite coating Corrosion behavior Plasma spray Stainless steel 316L Human body implant

Effect of Surface Treatment and Metallic Coating on Corrosion Behavior and Biocompatibility of Surgical 316L Stainless Steel Implant

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Journal of Materials Science & Technology 2012年第2期28卷 125-131页

作者： Ali Parsapour Saied Nouri Khorasani mohammad hossein Fathi Department of Materials Engineering Isfahan University of Technology Department of Chemical Engineering Isfahan University of Technology

Surface engineering technology is a suitable method for coatings on the metal surfaces or performing surface modification treatment, which can improve corrosion resistance and biocompatibility of metals. In this research, corrosion behavior of Nb coating on H2SO4 and HNO3 treated AISI stainless steel 316L （SS） was evaluated. Nb coating was carried out using physical vapor deposition process on the SS. Characterization techniques including scanning electron microscopy （SEM） and energy dispersive X-ray （EDX） technique were used to investigate the microstructure and morphology of the coated and treated SS. Electrochemical potentiodynamic tests were performed in two types of physiological solutions and compared with the pristine SS specimens. Cyclic polarization tests were performed to evaluate resistivity against pitting. Experimental results indicate that Nb coating and surface treatment of the SS had a positive effect on improvement of corrosion behavior. The decrease in corrosion current densities was significant for coated and treated specimens. The corrosion current density was much lower than the values obtained for pristine specimens.

关键词： 316L stainless steel Corrosion behavior Nb coating Surface treatment

Efficient one-pot synthesis of 1,3-diaryl-3H-benzo[f]chromenes using ferric hydrogensulfate

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Chinese Chemical Letters 2010年第12期21卷 1423-1426页

作者： hossein Eshghi Gholam hossein Zohuri Saman Damavandi mohammad Vakili Department of Chemistry School of SciencesFerdowsi University of MashhadMashhad 91775-1436Iran School of Chemistry Damghan University of Basic SciencesP.O.Box 36715-364DamghanIran

An efficient and easy method for one-pot three-component synthesis of l,3-disubstituted-3H-benzo[f]chromenes by the condensation of naphtol,aromatic aldehyde derivatives and phenylacetylene in the presence of ferric hydrogensulfate[Fe（HSO4）3], has been *** catalyst displayed high activity which afforded the corresponding 1,3-disubstituted-3H-benzo[f]chromenes in satisfying ***-substituted phenols were examined and the corresponding benzopyran derivatives were synthesized in moderate *** nature of the using catalyst made it reusable for further chemical reactions.

关键词： 1,3-Disubstituted-3H-benzo[f]chromenes Ferric hydrogensulfate One-pot synthesis Naphtopyran Benzopyran

A Comprehensive Overview on the Latest Progress in the Additive Manufacturing of Metal Matrix Composites: Potential, Challenges, and Feasible Solutions

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Acta Metallurgica Sinica(English Letters) 2021年第9期34卷 1173-1200页

作者： Mehran Dadkhah mohammad hossein Mosallanejad Luca Iuliano Abdollah Saboori Department of Applied Science and Technology Politecnico di TorinoCorso Duca Degli Abruzzi 2410129 TorinoItaly Department of Materials Engineering Isfahan University of Technology84156-83111 IsfahanIran Department of Management and Production Engineering Politecnico di TorinoCorso Duca Degli Abruzzi 2410129 TorinoItaly

Nowadays, as an emerging technology, additive manufacturing(AM) has received numerous attentions from researchers around the world. The method comprises layer-by-layer manufacturing of products according to the 3D CAD models of the objects. Among other things, AM is capable of producing metal matrix composites(MMCs). Hence, plenty of works in the literature are dedicated to developing different types of MMCs through AM processes. Hence, this paper provides a comprehensive overview on the latest research that has been carried out on the development of the powder-based AM manufactured MMCs from a scientific and technological viewpoint, aimed at highlighting the opportunities and challenges of this innovative manufacturing process. For instance, it is documented that AM is not only able to resolve the reinforcement/matrix bonding issues usually faced with during conventional manufacturing of MMCs, but also it is capable of producing functionally graded composites and geometrically complex objects. Furthermore, it provides the opportunity for a uniform distribution of the reinforcing phase in the metallic matrix and is able to produce composites using refractory metals thanks to the local heat source employed in the method. Despite the aforementioned advantages, there are still some challenges needing more attention from the researchers. Rapid cooling nature of the process, significantly different coe fficient of expansion of the matrix and reinforcement, processability, and the lack of suitable parameters and standards for the production of defect-free AM MMCs seem to be among the most important issues to deal with in future works.

关键词： Additive manufacturing Metal matrix composite Microstructure Interfacial bonding Mechanical properties