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Heat Transfer Analysis of MHD Power Law Nano Fluid Flow through Annular Sector Duct

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Journal of Thermal Science 2020年第1期29卷 169-181页

作者： AHMED Farhan iqbal Mazhar School of Natural Sciences National University of Science and Technology

Flow and heat transfer analysis of an electrically conducting MHD power law nano fluid is carried out through annular sector duct,under the influence of constant pressure *** types of nano particles(*** and TiO2)are used in power law nano *** implicit procedure,(SIP)is used to simulate the discretized coupled algebraic *** has been observed that volume fraction of nano particles,ϕand magnetic field parameter,Ha are favourable for the heat transfer rate,however,both resist the fluid *** of applied uniform transverse magnetic field exceeds in the case of shear thickening fluids(i.e.n>1)by increasing the value of Ha as compared to that in shear thinning fluids(i.e.n<1).Therefore,enhancement in heat transfer rate is comparably more in shear thickening ***,comparable limiting case study with published result is also carried out in this research paper.

关键词： electrically conducting power law nano fluid Cu nano particles TiO2 nano particles shear thickening fluid shear thinning fluid heat transfer rate friction factor

Synthesis of ITO Nanoparticles Prepared by the Degradation of Sulfide Method

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Chinese Physics Letters 2012年第7期29卷 239-241页

作者： majid.Farahmandjou Department of Physics Varamin Pishva BranchIslamic Azad UniversityVaraminIran

Indium tin oxide (ITO) nanoparticles are synthesized by the two-degradation sulfide and liquid-phase co-precipitation method under the given conditions with solutions of InCl3·4H2O and SnCl4·5H2O in the presence of *** sample powders were characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses after heat *** SEM results show that the size of the ITO particles prepared by the coprecipitation method is decreased to 100nm,whereas the size of the ITO prepared by degradation of sulfide increases to 1μm after heat *** XRD results reveal that the size of crystallite ITO particles is increased with increasing annealing *** the intensity ratio of I400/I222 has an increase of 29.07%for ITO prepared by the co-precipitation method.

关键词： sulfide method size

Chemical functionalization of chitosan biopolymer and chitosan-magnetite nanocomposite with sulfonic acid for acid-catalyzed reactions

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Chinese Journal of Chemical Engineering 2021年第11期34卷 154-161页

作者： majid Masteri-Farahani Samaneh Shahsavarifar Research Institute of Green Chemistry Faculty of ChemistryKharazmi UniversityTehranIran

Chemical functionalization of chitosan biopolymer and chitosan-magnetite nanocomposite was performed with sulfonic acid functional groups to achieve new solid acid *** sulfonic acid functional groups were created through the ring opening nucleophilic reaction of amine groups of chitosan with 1,4-butane *** transform infrared spectroscopy(FT-IR)and X-ray photoelectron spectroscopies(XPS)verified the successful sulfonic acid functionalization of *** obtained sulfonic acid functionalized chitosan-magnetite nanocomposite showed superparamagnetic properties according to the vibrating sample magnetometry analysis and exhibited magnetic separation feature from dispersed *** adsorption-desorption analysis indicated the increase in surface area after formation of chitosan-magnetite nanocomposite and functionalization with sulfonic *** of the prepared solid acids exhibited high catalytic activities in the acid-catalyzed acetic acid esterification with n-butanol and benzaldehyde acetalization with ethylene glycol as model ***,they can be reused several times without considerable loss of their activities.

关键词： Chitosan Magnetite Nanostructure Sulfonic acid Catalysis Esterification

Synthesis of clay-supported nanoscale zero-valent iron using green tea extract for the removal of phosphorus from aqueous solutions

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Chinese Journal of Chemical Engineering 2017年第7期25卷 924-930页

作者： Akbar Soliemanzadeh majid Fekri Department of Soil Sdence College of AgricultureShahid Bahonar University of KermanKermanlran

This study addresses the synthesis of nanoscale zero-valent iron(n ZVI) in the presence of natural bentonite(B-n ZVI) using green tea extract. The natural bentonite and B-n ZVI were then applied for the removal of phosphorus from aqueous solutions at various concentrations, p H levels and contact time. The desorption of phosphorus(P) from adsorbents was done immediately after sorption at the maximum initial concentration using the successive dilution method. The characterization of FTIR, SEM, and XRD indicated that n ZVI was successfully loaded to the surface of natural bentonite. The sorption of phosphorus on B-n ZVI was observed to be p H-dependent, with maximum phosphorus removal occurring at the p H range of 2 to 5. The results demonstrate that the maximum sorption capacities of natural bentonite and B-n ZVI were 4.61 and 27.63 mg·g^(-1), ***, Freundlich, and Redlich–Peterson models properly described the sorption isotherm data. For either adsorbent, desorption isotherms did not coincide with their corresponding sorption isotherms, suggesting the occurrence of irreversibility and hysteresis. The average percentages of retained phosphorus released from natural bentonite and B-n ZVI were 80% and 9%, respectively. The results indicated that sorption kinetics was best described by the pseudo-second-order model. The present study suggests that B-n ZVI could be used as a suitable adsorbent for the removal of phosphorus from aqueous solutions.

关键词： Green tea Nano zero-valent iron Natural bentonite Phosphorus Sorption

Optimal selection of annulus radius ratio to enhance heat transfer with minimum entropy generation in developing laminar forced convection of water-Al2O3 nanofluid flow

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Journal of Central South University 2017年第8期24卷 1850-1865页

作者： Siavashi majid Jamali Mohammad Applied Multi-Phase Fluid Dynamics Lab. School of Mechanical EngineeringIran University of Science and TechnologyTehranIran

Heat transfer and entropy generation of developing laminar forced convection flow of water-Al_2O_3 nanofluid in a concentric annulus with constant heat flux on the walls is investigated numerically. In order to determine entropy generation of fully developed flow, two approaches are employed and it is shown that only one of these methods can provide appropriate results for flow inside annuli. The effects of concentration of nanoparticles, Reynolds number and thermal boundaries on heat transfer enhancement and entropy generation of developing laminar flow inside annuli with different radius ratios and same cross sectional areas are studied. The results show that radius ratio is a very important decision parameter of an annular heat exchanger such that in each Re, there is an optimum radius ratio to maximize Nu and minimize entropy generation. Moreover, the effect of nanoparticles concentration on heat transfer enhancement and minimizing entropy generation is stronger at higher Reynolds.

关键词： nanofluid heat transfer enhancement forced convection entropy generation annulus radius ratio

Fabrication of phosphor bronze/Al two-phase material by recycling phosphor bronze chips using hot extrusion process and investigation of their microstructural and mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2020年第6期27卷 809-817页

作者： majid Hosseini Mohammad Hossein Paydar Department of Materials Science and Engineering School of EngineeringShiraz UniversityShiraz 71964-84334Iran

Despite the existence of conventional methods for recycling chips,solid-state techniques have become popular,whereby waste metals are directly recycled into consolidated products with the desired shapes and *** investigated the feasibility of recycling phosphor bronze chips through a hot extrusion process using aluminum powder as a metal binder for the fabrication of a metal-fiber-reinforced aluminum matrix *** do so,mixtures containing 20 vol%–50 vol%of chips were prepared,cold-compacted,and *** quality of the consolidated samples was evaluated by determining the density of the fabricated composites and studying their *** addition,we performed tensile and hardness tests to evaluate the mechanical properties of the fabricated *** also analyzed the fracture surfaces of the samples to study the fracture mechanism as a function of the volume fraction of phosphor bronze chips in the fabricated *** results indicated that the most effective consolidation occurred in the sample containing 20 vol%of chips extruded at 465℃in which the chips serve as ideal fibers for improving the mechanical properties,especially the ultimate tensile strength,in comparison with those of Al matrixes that contain no chips but are produced under the same conditions.

关键词： recycling hot extrusion metal–metal composite phosphor bronze chips aluminum powder

Relative Canonical Modules and Some Duality Results

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Algebra Colloquium 2019年第2期26卷 351-360页

作者： majid Rahro Zargar Department of Engineering Sciences Faculty of Advanced Technologies University of Mohaghegh Ardabili Namin Ardabil Iran Department of Engineering Sciences Faculty of Advanced Technologies Sabalan University of Advanced technologies (SUAT) Namin Iran School of Mathematics Institute for Research in Fundamental Sciences (IPM)

Let (R, m) be a relative Cohen–Macaulay local ring with respect to an ideal a of R and set c to be ht a. We investigate some properties of the Matlis dual of the R-module H^ca(R), and we show that such modules behave like canonical modules over Cohen–Macaulay local rings. Moreover, we provide some duality and equivalence results with respect to the module H^ca(R)^∨, and these results lead us to achieve generalizations of some known results, such as the local duality theorem, which have been provided over a Cohen–Macaulay local ring admiting a canonical R-module.

关键词： local cohomology canonical module complex relative Cohen-Macaulay module

Effect of Minor Alloying on Crystallization Behavior and Thermal Properties of Zr_(64.5)Ni_(15.5)Al_(11.5)Cu_(8.5) Bulk Amorphous Alloy

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Journal of Materials Science & Technology 2011年第6期27卷 534-538页

作者： Muhammad iqbal Javed iqbal Akhter Haifeng Zhang Zhuangqi Hu MicrostructuralStudies Group Physics Division Pakistan Institute of Nuclear Science and Technology (PINSTECH) P.O. Nilore Islamabad Pakistan Shenyang Nationel Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Minor alloying plays an important role in the synthesis and improvement of thermal stability of bulk metallic glasses（BMGs）.The present study was conducted to investigate the effect of minor additions of Y,Ti and Nb on the crystallization behavior and the thermal properties of Zr64.5Ni15.5Al11.5Cu8.5 *** parameters and the activation energies for crystallization were calculated for four（Zr0.645Ni0.155Al0.115-Cu0.085）100-xMx（M=Y,Ti and Nb,while x=0,2 at.） *** present alloys have wide supercooled liquid region of ≥87 *** activation energy was found to be greater than 300 kJ/mol for the base *** crystalline phases were identified in the samples annealed at 823 K for 20 *** glass transition temperature（Trg） and other thermal parameters such as γ,δ and β were improved by Y and Ti *** addition resists crystallization below annealing temperature 713 K,however,its effect on thermal properties is not very promising.

关键词： Activation energy Thermal properties Glass-forming ability Thermal stability Precipitation Microstructure

Effects of green iron nanoparticles on iron changes and phytoavailability in a calcareous soil

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Pedosphere 2021年第5期31卷 761-770页

作者： Akbar SOLIEMANZADEH majid FEKRI Department of Soil Science College of AgricultureShahid Bahonar University of KermanKerman ***(Iran)

Green iron nanoparticles(Fe NPs)can be a practical solution to combat iron(Fe)deficiency in calcareous agricultural *** main aim of the present work was to assess the effects of green Fe NPs on Fe availability in calcareous *** this purpose,green Fe NPs were synthesized using green tea(G-Fe NPs),Shirazi thyme(T-Fe NPs),walnut green hull(W-Fe NPs),and pistachio green hull(P-Fe NPs)extracts and applied as a source of Fe fertilizer to sorghum(Sorghum bicolor ***)*** of X-ray diffraction(XRD),scanning electron microscopy(SEM),and dynamic light scattering(DLS)indicated that the green Fe NPs were amorphous in nature and the polyphenols obtained from plant-part extracts acted as both capping and reducing *** to the behavior of Fe-ethylenediamine-N,N-bis(2-hydroxyphenyl)acetic acid(Fe-EDDHA)in calcareous soils,G-Fe NPs,T-Fe NPs,W-Fe NPs,and P-Fe NPs increased Fe release compared with the control and FeSO_(4) *** Fe release data fitted well to the power function,intra-particle diffusion,and Elovich kinetic *** to the pot experiment,the increment in soil Fe availability upon Fe-EDDHA and Fe NPs application led to an increase in Fe uptake,growth,and photosynthetic pigment contents of the sorghum *** further research is needed to evaluate the residual effect and environmental impact of green Fe NPs,they may be an appropriate substitute for traditional Fe fertilizers in calcareous soils.

关键词： chlorophyll content Fe fertilizer Fe release green chemistry natural polyphenols sorghum