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Micromechanical simulation and experimental investigation of aluminum-based nanocomposites

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Defence Technology（防务技术） 2021年第1期17卷 196-201页

作者： Mohammad javad Ghasemi Mohammad Silani Ali Maleki Mostafa Jamshidian Department of Mechanical Engineering Isfahan University of TechnologyIsfahan84156-83111Iran

Ceramic reinforced metal matrix nanocomposites are widely used in aerospace and auto industries due to their enhanced mechanical and physical *** this research,we investigate the mechanical properties of aluminum/Nano-silica composites through experiments and ***/Nanosilica composite samples with different weight percentages of silica nanoparticles are prepared via powder *** this method,Nano-silica and aluminum powders are mixed and compressed in a mold,followed by sintering at high *** tensile testing of the nanocomposite samples shows that adding one percent of Nano-silica causes a considerable increase in mechanical properties of nanocomposite compared to pure aluminum.A computational micromechanical model,based on a representative volume element of aluminum/silica nanocomposite,is developed in a commercial finite element *** model employs an elastoplastic material model along with a ductile damage model for aluminum matrix and linear elastic model for nano-silica *** careful determination of model parameters from the experimental results of pure aluminum samples prepared by powder metallurgy,the proposed computational model has shown satisfactory agreement with *** validated computational model can be used to perform a parametric study to optimize the microstructure of nanocomposite for enhanced mechanical properties.

关键词： Aluminum/nano-silica composites Powder metallurgy Micromechanics

The Influence of Morphology on Photo-catalytic Activity and Optical Properties of Nanocrystalline ZnO Powder

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Nano-Micro Letters 2012年第4期4卷 197-201页

作者： javad Moghaddam Sara Mollaesmail Saeed Karimi Materials and Metallurgical Engineering Department Advanced Materials Research Center Sahand University of Technology School of Metallurgy and Materials Engineering University of Tehran

ZnO nano-particles were synthesized via an ammonical ammonium carbonate solution by precipitation method in presence of some additives such as urea, oleic and stearic acid. The morphology and crystallinity of the obtained zinc oxide particles depend critically on the type of additive which was used. Additives also affected the crystal orientation of precipitate nano-particles. SEM, XRD, BET and UV-visible were used to characterize morphology, microstructure, specific surface area and optical properties of the ***-catalysis properties of the as-prepared ZnO powders were evaluated by degradation of methyl red(acid red) in aqueous solution exposed to UV-light. Results suggested a close relationship among the morphology,size and surface area on photo-catalysis and optical properties of the particles. The widest Egvalue(3.56 e V),highest degradation and decolorization efficiency(99%) were obtained from a sample with the smallest grain size(largest surface area) which were used urea as an additive.

关键词： Nano-particles ZnO Precipitation method Optical properties Photocatalytic activity

Clean synthesis of novel spiro[indene-2,2'-[1,3,5]-oxathiazine]-1,3-diones in water

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Chinese Chemical Letters 2017年第5期28卷 1079-1082页

作者： Mahboobeh Salehpour javad Azizian Hassan Kefayati Department o.f Chemistry Science and Research BranchIslamic Azad UniversityP.O.Box 19395-1775TehranIran Department of Chemistry Rasht BranchIslamic Azad UniversityRashtIran

In this work,we have designed an efficient and convenient method for the synthesis of novel spiro[indene-2,2＇-[1,3,5]oxathiazine]-1,3-diones by the one-pot,three component condensation of tetramethyl guanidine,ninhydrin,and isothiocyanates in *** purification,green reaction conditions,easy performance and good yields are some advantages of this procedure.

关键词： Spiro[indene-oxathiazine] Tetramethyl guanidine Ninhydrin Oxathiazine

A population-feedback control based algorithm for well trajectory optimization using proxy model

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第2期9卷 281-290页

作者： javad Kasravi Mohammad Amin Safarzadeh Abdonabi Hashemi National Iranian Drilling Company AhwazIran Tehran Energy Consultants (TEC) Company TehranIran Department of Petroleum Engineering Petroleum University of TechnologyAhwazIran

Wellbore instability is one of the concerns in the field of drilling *** phenomenon is affected by several factors such as azimuth,inclination angle,in-situ stress,mud weight,and rock strength *** these factors,azimuth,inclination angle,and mud weight are *** objective of this paper is to introduce a new procedure based on elastoplastic theory in wellbore stability solution to determine the optimum well trajectory and global minimum mud pressure required(GMMPR).Genetic algorithm(GA) was applied as a main optimization engine that employs proportional feedback controller to obtain the minimum mud pressure required(MMPR).The feedback function repeatedly calculated and updated the error between the simulated and set point of normalized yielded zone area(NYZA).To reduce computation expenses,an artificial neural network(ANN) was used as a proxy(surrogate model) to approximate the behavior of the actual wellbore *** methodology was applied to a directional well in southwestern Iranian *** results demonstrated that the error between the predicted GMMPR and practical safe mud pressure was 4%for elastoplastic method,and 22%for conventional elastic solution.

关键词： Elastoplastic theory Normalized yielded zone area(NYZA) Optimization Well trajectory Proportional feedback controller Proxy model

Application of Statistical Methods to Biomarkers for Geochemical Evaluation and Genetic Type Determination of Gas Condensates in the Persian Gulf and Coastal Fars,Southern Iran

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1246-1256页

作者： Mohammad javad SEIDY Mohammad Hossein SABERI Petroleum Engineering Department Semnan UniversitySemnanIran The New Technology Campus Petroleum Engineering DepartmentSemnan UniversitySemnanIran

In a comprehensive geochemical study,the genetic relationships among 14 samples of gas condensates from the Persian Gulf were investigated for the purpose of evaluating the respective source rocks in terms of both age and sedimentary *** analysis was used for categorization and determination of a certitude range to determine the genetic type of the condensate families in the studied *** samples were collected from Late Permian-Triassic reservoirs(Dalan and Kangan formations)located in 6 gasfields(gas condensate)hosting some of Iran’s most important gas/gas condensate *** by gas chromatography-mass spectrometry(GC-MS),a total of 16 biomarker parameters(10 maturity-related parameters and 6 sedimentary environment-related parameters)were used to evaluate the samples in terms of thermal maturity(and hence their positions in the maturity chart),the sedimentary environment of the source rock and the *** of Hierarchical Clustering Analysis(HCA)and Principal Component Analysis(PCA)to the collected data led to the categorization of the samples into three main genetic groups,Ⅰ-Ⅲ.GroupsⅠandⅢwere found to be located in the east and the west of the Persian Gulf,respectively,while GroupⅡwas developed between the two other groups.

关键词： gas condensate satistical methods genetic linkage thermal maturation Persian Gulf Coastal Fars

Numerical study of aerosol particle deposition in simple and converging-diverging micro-channels with a slip boundary condition at the wall

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Particuology 2014年第2期12卷 100-105页

作者： Seyed Mohammad javad Hosseini Ataallah Soltani Goharrizi Bahador Abolpour Department of Chemical Engineering Faculty of EngineeringShahid Bahonar University of Kerman

The design of micro-devices involving aerosol transport requires the study of the deposition of aerosols in micro-channels. In this study, the slip and no-slip boundary conditions for the gas flow regime were applied to the Navier-Stokes equations to obtain the particle deposition in simple and converging-diverging micro-channels. The equation of particle motion included inertial, viscous, Brownian, and gravity terms. It was found that the ratio of gravity to inertial effects controls the deposition of particles with diameters of 0.1-1 μm, and the ratio of diffusion to inertial effects controls the deposition of particles with diameters of 0.01-0.001 i^m. Comparison between the no-slip and slip flow regimes showed that the deposition of 0.1- to 1-μm-diameter particles was less and the deposition of 0.01- to 0.001-1μm-diameter particles was greater for the slip flow regime. There was no significant difference between slip and no-slip flow regimes for the deposition of 0.01- to 0.1-μm-diameter particles. Finally, it was shown that the stagnated gas in the corners of the converging-diverging micro-channel produced similar gas velocity profiles under the slip and no-slip flow regimes.

关键词： Aerosol depositionMicro-channelConverging-diverging micro-channelSlip boundary condition

Zinc oxide nanoparticles:A highly efficient and readily recyclable catalyst for the synthesis of xanthenes

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Chinese Chemical Letters 2012年第11期23卷 1225-1229页

作者： javad Safaei-Ghomi Mohammad Ali Ghasemzadeh Department of Organic Chemistry Faculty of ChemistryUniversity of Kashan

A novel and efficient route for the synthesis of 1,8-dioxooctahydroxanthenes and 14-aryl-14H-dibenzo[a,j]xanthenes is described through one-pot multi-component reaction of dimedone and 2-naphthol with various aryl aldehydes using ZnO nanoparticles under solvent-free conditions. This method provides a novel and improved pathway for the synthesis of xanthenes in the terms of excellent yields, short reaction times, reusability and low catalyst loading.

关键词： ZnO nanoparticles Xanthene Solvent-free Multi-component reaction Heterogeneous catalysts

Thermo-mechanical analysis of an SI engine piston using different boundary condition treatments

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Journal of Central South University 2015年第10期22卷 3817-3829页

作者： Amir-Hasan Kakaee javad Gharloghi Aliasghar Foroughifar Abdoreza Khanlari School of Automotive Engineering Iran University of Science & Technology Iran Khodro Company Department of Mechanical Engineering Golpayegan University of Technology School of Industrial Engineering South Tehran Branch Islamic Azad University

Heat transfer of an SI engine's piston is calculated by employing three different methods based on resistor-capacitor model with the help of MATLAB code, and then the piston is thermo-mechanically analyzed using commercial ANSYS code. The results of three methods are compared to study their effects on the piston thermal behavior. It is shown that resistor-capacitor model with less number of equations and consequently less solution time, is an appropriate method for solving problems of engine piston heat transfer. In the second part, the thermal stresses due to non-uniform temperature distribution, and mechanical stresses due to mechanical loads are calculated. Finally, the temperature distributions as a thermal load along with mechanical loads are applied to the piston to determine the total stress distribution and critical fracture zones. It is found that the amount of thermal stresses is considerable.

关键词： piston temperature boundary condition stress thermo-mechanical analysis

Colostrum and milk performance,and blood immunity indices and minerals of Holstein cows receiving organic Mn,Zn and Cu sources

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Animal Nutrition 2020年第1期6卷 61-68页

作者： Habiballah Roshanzamir javad Rezaei Hassan Fazaeli Department of Animal Science Faculty of AgricultureTarbiat Modares UniversityP.O.Box 14U5-336TehranIran Animal Science Research Institute of Iran Agricultural ResearchEducation and Extension Organization(AREEO)Karaj.***Iran

Effects of supplementing the basal diets with Mn,Zn and Cu,as sulphate,glycine or methionine salts,on colostrum and milk performance,some blood immunity indices and blood minerals of pre-and postpartum Holstein cows were *** cows in different groups received:1)a diet without supplementary Mn,Zn and Cu(control),2)a diet containing Mn,Zn and Cu sulphates,3)a diet containing Mn,Zn and Cu glycine,or 4)a diet containing Mn,Zn and Cu methionine with 10 cows per group from d 60 before calving(dry period)to d 100 of *** matter intake(DMI),dry matter digestibility(DMD),colostrum and milk performance,milk somatic cell count(SCC),blood and milk total antioxidant capacity(TAC),immunoglobulin M(IgM)and immunoglobulin A(IgA),and blood Mn,Zn and Cu were *** supplementation with Mn,Zn and Cu as methionine,glycine or sulphate salts had positive effects on DMD,DMI,colostrum and milk performance,milk SCC,and blood Mn and *** of Mn,Zn and Cu in diets could increase(P0.05),however,the blood concentrations of IgA(except d 1 postpartum)and IgM in the cows supplemented with organic Mn,Zn and Cu were higher(P<0.05)than those in the cows receiving the sulphate sources of ***,dietary supplementation of Mn,Zn and Cu as methionine,glycine or sulphate salts can improve colostrum and milk performance,blood Zn and Mn and immunity indices in Holstein cows and their new-born ***,the organic sources of Mn,Zn and Cu have advantage over the sulphate forms in terms of the blood immunoglobulins.

关键词： Antioxidant status Cattle Immunity Organic trace minerals Performance