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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 39-45页

作者： Mohsen Hajizamani Mostafa alizadeh Seyed Ahmad Jenabali-Jahromi Department of Metals Institute of Science and High Technology and Environmental SciencesGraduate University of Advanced Technology Department of Materials Science and Engineering School of EngineeringShiraz University

A thermomechanical process （TMP） consisting of three cycles of cold pressing at 154 MPa and liquid-phase sintering at 600 ℃ for 30 min in each cycle was applied to modify the microstructure of nanostructured A1-Zn-Mg alloy. The alloy powders were produced by mechanical alloying. Also, solid-state sintering at 550℃ for 90 min was done to compare the results with those obtained from the TMP. The powders and the thermomechanically （TM） processed samples were analyzed by XRD to reveal the present phases in addition to calculating the crystallite size changes by the Wil- liamson-Hall method. Moreover, scanning electron microscope was employed to observe the morphology of the powder and the microstructures of the sintered and the TM processed samples. The results revealed that the TMP affected the microstructure noticeably as well as the microhardness by removing the continuous grain boundary porosities and uniform distribution of the intermetallic phase particles as well as obtaining a near globular microstructure after the second cycle. Also, the average grain sizes in the first and the second cycles of the TMP were lower than those of the sintered sample. Furthermore, nanocrystalline grains were stable up to the second cycle of the TMP.

关键词： Thermomechanical processing AI-Zn-Mg alloy Intermetallics Sintering Grain growth

Tailoring particle shape for enhancing the homogeneity of powder mixtures:Experimental study and DEM modelling

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Particuology 2021年第1期19卷 58-68页

作者： Maryam Asachi Mohammadreza alizadeh Behjani Ehsan Nourafkan Ali Hassanpour School of Chemical and Process Engineering University of LeedsLeeds LS29JTUK School of Maths and Physics University of LincolnBrayford PoolLincolnLN67TSUK

The effect of particle shape modification on the segregation reduction of enzyme granules in laundry detergent powder mixtures was investigated,both experimentally and computationally using Deseret Element Method(DEM).The shape of modified enzyme particles was in such a way that the large and dense enzyme particles were layered by other fine particles in the detergent powder,by means of a process known in the literature as“seeded granulation”.It is found that the homogeneity of modified enzyme particles could be improved significantly comparing to the original spherical enzyme particles in powder ***,the results of this research demonstrated that the segregation-induced properties of the dense/spherical enzyme particles could be lowered by altering their shape,which could enable the enzyme particles to behave almost similar to other ingredients during the pile formation process.

关键词： Segregation minimisation Particle shape modification Seeded granulation Near-infrared spectroscopy Laundry detergent powders Discrete Element Method

Wildfire events at the Triassic-Jurassic boundary of the Tabas Basin,Central Iran

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International Journal of Coal Science & Technology 2021年第5期8卷 897-907页

作者： Majid Alipour Bahram alizadeh AmirAbbas Jahangard AhmadReza GandomiSani Department of Petroleum Geology and Sedimentary Basins Faculty of Earth SciencesShahid Chamran University of AhvazAhvazIran Exploration Directorate(ED) National Iranian Oil CompanyTehranIran

This paper presents organic geochemical evidence pointing to the occurrence of wildfire events at the Triassic-Jurassic boundary in Central *** studied outcrop section(the Kamarmacheh Kuh section)is comprised of the Upper Triassic Nayband Formation which passes conformably into the Lower Jurassic Ab-e-Haji Formation with no sharp *** petrographical studies reveal a higher concentration of semi-fusinite macerals and microscopic charcoal at the boundary between studied *** observation can be an evidence for widespread wildfire events at the Triassic-Jurassic boundary of the studied *** these fires,vast areas of land were exposed for erosion and large volumes of clastic sediments were provided due to increased *** agrees well with previous sedimentological and stratigraphical studies suggesting a major change in the depositional conditions from marine to non-marine at the Triassic-Jurassic boundary of the Tabas *** findings can have important implications about paleo-depositional settings of the studied formations and the nature of the associated organic matter.

关键词： Wildfire events Triassic-Jurassic boundary Nayband and Ab-e-Haji formations Tabas Basin Central Iran

Synthesis of organosoluble polyamides with bulky triaryl imidazole pendent group

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Chinese Chemical Letters 2009年第8期20卷 961-964页

作者： Mousa Ghaemy Hossein Behmadi Raouf alizadeh Faculty of Chemistry Mazandaran UniversityBabolsar 47416-1467 Iran

New unsymmetrical diamine monomer containing triaryl imidazole pendent group, 4-[4-（4,5-diphenyl-1H-imidazol-2-y1）phe- noxy]-1,3-benzenediamine, was synthesized via aromatic substitution reaction of 1-chloro-2,4-dinitrobenzene with 4-（4,5- diphenyl-1H-imidazol-2-y1）pbenol, followed by palladium-catalyzed hydrazine reduction. This new monomer was further confirmed by FT-IR, IH NMR and ^13C NMR. Novel polyamides having pendant triaryl imidazole group were prepared by the phosphorylation polycondensation of four commercially aromatic dicarboxylic acids with the prepared diamine. Inherent viscosities of polyamides were in the range 0.42-0.53 dL/g indicating formation of medium molecular weight polymers. Polyamides exhibited glass-transition temperature （Tg） in the range 236-265 ℃. These polymers are essentially amorphous and were soluble in polar aprotic solvents such as DMF, NMP, DMAc. The 10% weight loss temperatures in air atmosphere, measured by TGA were in the range 350-373 ℃ indicating their good thermal stabilities. ？2009 Mousa Ghaemy. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Polyamides Bulky pendent group Thermal properties Imidazole

Hot Extrusion Process Effect on Mechanical Behavior of Stir Cast Al Based Composites Reinforced with Mechanically Milled B_4C Nanoparticles

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Journal of Materials Science & Technology 2011年第12期27卷 1113-1119页

作者： A. alizadeh E. Taheri-Nassaj M. Hajizamani Department of Materials Science and Engineering Tarbiat Modares University Faculty of Materials and Manufacturing Processes MUT University

In this study, aluminum alloy （Al-2 wt% Cu） matrix composites reinforced with I, 2 and 4 wt% boron carbide nanoparticles fabricated through mechanical milling with average size of 100 nm were fabricated via stir casting method at 850℃. Cast ingots of the matrix alloy and the composites were extruded at 500℃ at an extrusion ratio of 10：1 to investigate the effects of hot extrusion on the mechanical properties of the composites. The microstructures of the as-cast and the extruded composites were investigated by scanning electron microscopy （SEM）. Density measurement, hardness and tensile tests were carried out to identify the mechanical properties of the composites. The extruded samples revealed a more uniform distribution of B4C nanoparticles. Also, the extruded samples had strength and ductility values superior to those of the as-cast counterparts. In the as-cast and the extruded samples, with increasing amount of B4C nanoparticles, yield strength and tensile strength increased but e^ongation to fracture decreased.

关键词： Stir casting Hot extrusion Al matrix composite B4C nanoparticles Mechanicalmilling

Viscous fluid damping in a laterally oscillating finger of a comb-drive micro-resonator based on micro-polar fluid theory

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Acta Mechanica Sinica 2016年第3期32卷 397-405页

作者： Sahra Azma Ghader Rezazadeh Rasoul Shabani Elnaz alizadeh-Haghighi Department of Mechanical Engineering Faculty of Engineering Urmia University

Viscous damping is a dominant source of energy dissipation in laterally oscillating micro-structures. In microresonators in which the characteristic dimensions are comparable to the dimensions of the fluid molecules, the assumption of the continuum fluid theory is no longer justified and the use of micro-polar fluid theory is indispensable. In this paper a mathematical model was presented in order to predict the viscous fluid damping in a laterally oscillating finger of a micro-resonator considering micro-polar fluid theory. The coupled governing partial differential equations of motion for the vibration of the finger and the micro-polar fluid field have been derived. Considering spin and no-spin boundary conditions, the related shape functions for the fluid field were presented. The obtained governing differential equations with time varying boundary conditions have been transformed to an enhanced form with homogenous boundary conditions and have been discretized using a Galerkin-based reduced order model. The effects of physical properties of the micro-polar fluid and geometrical parameters of the oscillating structure on the damping ratio of the system have been investigated.

关键词： Micro-electro-mechanical systems(MEMS) Micro-resonator Micro-polar theory Viscous fluid damping Galerkin method

Local Strain Energy Density Applied to Bainitic Functionally Graded Steels Plates Under Mixed-Mode(Ⅰ+Ⅱ) Loading

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Acta Metallurgica Sinica(English Letters) 2015年第2期28卷 164-172页

作者： H.Salavati Y.alizadeh F.Berto Department of Mechanical Engineering Amirkabir University of Technology Department of Management and Engineering University of Padova

In this paper, the averaged value of the strain energy density （SED） over a control volume is used to predict the critical load of V-notched specimens made of functionally graded steels （FGSs） under mixed-mode loading. The studied FGSs contain ferritic and austenite phases in addition to bainitic layer produced by electroslag remelting. The mechanism- based strain gradient plasticity theory is used to determine the flow stress （yield stress or ultimate stress） of each layer. The Young＇s modulus and the Poisson＇s ratio have been assumed to be constant, while other mechanical properties vary exponentially along the specimen width. The control volume is centered in relation to the maximum principal stress present on the notch edge and assumes a crescent shape. The points belonging to the volume perimeter are obtained numerically. In the present contribution, the effects of notch radius and notch depth on the SED and the critical load are studied. The notch radius varies from 0.2 to 2.0 mm, and the notch depth varies from 5 to 7 ram. By using the SED approach and finite element simulations, the critical load is determined, and the obtained results show a sound agreement with the experimental results.

关键词： Functionally bainitic graded steel Strain energy density Mechanism-based strain gradientplasticity theory Critical load Notch radius Notch depth

Modulation of the gut microbiota represents a new management for non-alcoholic fatty Iiver disease

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Hepatobiliary Surgery and Nutrition 2020年第2期9卷 223-226页

作者： Farnush Bakhshimoghaddam Mohammad alizadeh Student Research Committee Department of Nutrition Department of Nutrition Food and Beverages Safety Research CenterFaculty of MedicineUrmia University of Medical SciencesUrmiaIran

With the worldwide spread of diet westernization,sedentary lifestyle,and obesity,non-alcoholic fatty liver disease(NAFLD)has becoming frequent *** is the presence of hepatic fat infiltration more than 5%of liver cells,in lack of alcohol abuse or steatogenic *** includes a spectrum of liver disorder,ranging from steatosis and non-alcoholic steatohepatitis(NASH)to fibrosis,cirrhosis and hepatocellular carcinoma(1).Metabolic syndrome and systemic micro-inflammation are the most relevant metabolic disorders related to this spectrum of diseases(2).There is currently no approved pharmacological treatment for *** management strategy of NAFLD involves lifestyle interventions,including diet,exercise,and behavior modification(1).

关键词： drugs inflammation becoming

DHT-and blockchain-based smart identification for video conferencing

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Blockchain(Research and Applications) 2022年第2期3卷 90-101页

作者： Morteza alizadeh Karl Andersson Olov Schelen Department of Computer Science Electrical and Space EngineeringLuleåUniversity of TechnologySE-93187SkellefteåSweden

Video conferencing applications help people communicate via the Internet and provide a significant and consistent basis for virtual ***,integrity,security,identification,and authentication problems are still *** video conference technologies typically rely on cloud systems to provide a stable and secure basis for executing tasks and *** the same time,video conferencing applications are being migrated from centralized to decentralized solutions for better performance without the need for third-party *** article demonstrates a decentralized smart identification scheme for video conferencing applications based on biometric technology,machine learning,and a decentralized hash table combined with blockchain *** store users'information on a distributed hash table and transactional events on the distributed ledger after identifying users by implementing machine learning ***,we leverage distributed ledger technology's immutability and traceability properties and distributed hash table unlimited storage feature to improve the system's storage capacity and immutability by evaluating three possible *** experimental results show that an architecture based on blockchain and distributed hash table has better efficiency but needs a longer time to execute than the two other architectures using a centralized database.

关键词： Video conferencing Blockchain IPFS Decentralized web hosting Machine learning

Improvement strategies for Ni-based alcohol steam reforming catalysts

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Journal of Energy Chemistry 2023年第11期86卷 447-479,I0010页

作者： Alex Desgagnés Ommolbanin alizadeh Sahraei Maria C.Iliuta UniversitéLaval Département de Génie Chimique1065 Avenue de la MédecineQuébecQC G1V 0A6Canada

Steam reforming(SR)of fossil methane is already a well-known,documented and established expertise in the industrial sector as it accounts for the vast majority of global hydrogen *** a sustainable development perspective,hydrogen production by SR of biomass-derived feedstock represents a promising alternative that could help to lower the carbon footprint of the traditional *** this regard,bio-alcohols such as methanol,ethanol or glycerol are among the attractive candidates that could serve as green hydrogen carriers as they decompose at relatively low temperatures in the presence of water compared to methane,allowing for improved H_(2)***,significant challenges remain regarding the activity and stability of nickel-based catalysts,which are most widely used in alcohol SR processes due to their affordability and ability to break C–C,O–H and C–H bonds,yet are prone to rapid deactivation primarily caused by coke deposition and metal particle *** this state-of-the-art review,a portfolio of strategies to improve the performance of Ni-based catalysts used in alcohol SR processes is unfolded with the intent of pinpointing the critical issues in catalyst *** examination of the literature reveals that the efforts tackling these recurring issues can be directed at the active metal,either by tuning Ni dispersion and Ni-support interactions or by targeting synergistic effects in bimetallic systems,while others focus on the support,either by modifying acid-base character,oxygen mobility,or by embedding Ni in specific crystallographic *** review provides a very useful tool to orient future work in catalyst development.

关键词： H2 production Alcohol steam reforming Ni-based catalysts Catalyst development Sintering Coke formation