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Applied mathematics and mechanics(English Edition) 2016年第6期37卷 725-740页

作者： A.r.SETOODEH m.rEZAEI m.r.zendehdel shahri Faculty of mechanical and Aerospace Engineering Shiraz University of Technology

The linear and nonlinear torsional free vibration analyses of functionmly graded micro/nuno-tubes （FGmTs） are analytically investigated based on the couple stress theory. The employed non-classical continuum theory contains one material length scale parameter, which can capture the small scale effect. The FGmT model accounts for the through-radius power-law variation of a two-constituent material. Hamilton＇s principle is used to develop the non-classical nonlinear governing equation. To study the effect of the boundary conditions, two types of end conditions, i.e., fixed-fixed and fixed-free, are considered. The derived boundary value governing equation is of the fourthorder, and is solved by the homotopy analysis method （HAm）. This method is based on the Taylor series with an embedded parameter and is capable of providing very good approximations by means of only a few terms, if the initial guess and the auxiliary linear operator are properly selected. The analytical expressions are developed for the linear and nonlinear natural frequencies, which can be conveniently used to investigate the effects of the dimensionless length scale parameter, the material gradient index, and the vibration amplitude on the natural frequencies of FGmTs.

关键词： torsional vibration nonlinear vibration micro/nano-tube functionallygraded material (FGm) couple stress theory size effect

Study of Transport Properties in Armchair Graphyne Nanoribbons: A Density Functional Approach

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Communications in Theoretical Physics 2016年第7期65卷 143-148页

作者： S.Golafrooz shahri m.r.roknabadi N.Shahtahmasebi m.Behdani Department of Physics Ferdowsi University of Mashhad

In present paper, the non-equilibrium Green function(NEGF) method along with the density functional theory(DFT) are used to investigate the effect of width on transport and electronic properties of armchair graphyne(γ-graphyne) nanoribbons. The results show that all the studied nanoribbons are semiconductor and their band gaps decrease as the widths of nanoribbons increase, which will result in increasing current at a certain voltage. Also our results show the promising application of armchair graphyne nanoribbons in nano-electrical devices.

关键词： transport properties density functional theory graphyne nanoribbons non-equilibrium green function

mineralogy, Geochemistry, Fluid Inclusion and Oxygen Isotope Investigations of Epithermal Cu±Ag Veins of the Khur Area, Lut Block,Eastern Iran

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Acta Geologica Sinica(English Edition) 2018年第3期92卷 1139-1156页

作者： m.Javidi mOGHADDAm m.H.KArImPOUr K.Ebrahimi NASrABADI m.r.Haidarian shahri A.malekzadeh SHAFArOUDI Department of Geology Faculty of Science Ferdowsi University of Mashhad research Center for Ore Deposit of Eastern Iran Ferdowsi University of Mashhad

The Khur metallogenic district is located in a volcanic-plutonic belt in the central Lut Block(central eastern Iran). mineralization occurs in middle Eocene andesitic tuff and along four main vein systems trending northwest-southeast(Shurk, mir-e-Khash, Shikasteh Sabz and Ghar-e-Kaftar veins).microscopic studies reveal that the veins contain bornite, chalcocite, pyrite, tennantite together with minor sphalerite and chalcopyrite as hypogene minerals and chalcocite, digenite, covellite, valleriite,malachite, azurite, atacamite, hematite, and goethite as supergene minerals. The ore bodies are accompanied by narrow but intensely developed wall rock alterations of argillization, carbonatization and silicification. Copper content reaches 6.5, 2.4, 4.2 and 5% in mir-e-Khash, Shikasteh Sabz, Ghar-eKaftar and Shurk, respectively. microthermometric measurements of quartz-and calcite-hosted fluid inclusions indicate that the mineralization might be derived from a moderately saline hydrothermal fluid at temperatures between 175-316℃. Calculated δO values of water in equilibrium with quartz and calcite for Khur veins suggest that the fluid might have had a magmatic source, but theO-depletion was developed through mixing with meteoric water. Copper deposition in Khur veins is believed to have been largely caused by mixing, although wall rock reactions may also have occurred. The Khur veins are classified as volcanic-subvolcanic hydrothermal-related vein deposits.

关键词： fluid inclusion oxygen isotopes Khur veins Lut Block Iran

Optimization of plasma electrolyte oxidation process parameters for corrosion resistance of mg alloy

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Journal of magnesium and Alloys 2020年第2期8卷 431-440页

作者： Z.shahri S.r.Allahkaram r.Soltani H.Jafari School of metallurgy and materials Engineering College of EngineeringUniversity of TehranP.O.Box:11155-4563TehranIran materials Engineering Department Faculty of Mechanical EngineeringShahid Rajaee Teacher Training UniversityTehranIran

Plasma electrolyte oxidation(PEO)is a surface treatment method with high dependency on the process *** paper focuses on maximizing the corrosion resistance of PEO coatings applied on mg-5Zn-0.4Ca(ZX504)alloy by optimizing the process *** this purpose,the Taguchi method based on LI8 orthogonal array with mixed level design was used for optimization and determining effective *** process factors including electrolyte concentration,current density,frequency and duty cycle were considered at different *** corrosion resistance,as the performance indicator,was obtained using electrochemical impedance spectroscopy *** characteristics were also evaluated using SEm(scanning electron microscopy),EDS(energy dispersive spectroscopy),profilometer and contact angle *** statistical analysis showed that the optimum condition could be obtained at a current density of 200 mA/cm^2,frequency of 500Hz and at a duty cycle of 30%,in an electrolyle containing 15 g/L NazPO·12H2O and 10g/L KF.

关键词： Plasma electrolyte oxidation Optimization Taguchi Corrosion ZX504 alloy

Nucleon/nuclei polarized structure function,using Jacobi polynomials expansion

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Chinese Physics C 2010年第9期34卷 1534-1537页

作者： A.mirjalili m.m.Yazdanpanah F.Taghavi-shahri S.Atashbar Tehrani Physics Department Yazd University School of Particles and Accelerators Institute for Research in Fundamental Sciences (IPM) Physics Department Kerman Shahid Bahonar University

We use the constituent quark model to extract polarized parton distributions and finally polarized nucleon structure *** to limited experimental data which do not cover whole （x,Q 2 ） plane and to increase the reliability of the fitting,we employ the Jacobi orthogonal polynomials *** will be possible to extract the polarized structure functions for Helium,using the convolution of the nucleon polarized structure functions with the light cone moment *** results are in good agreement with available experimental data and some theoretical models.

关键词： perturbative QCD nucleon and nuclei structure function jacobi polynomials

Glass forming ability and mechanical properties of Nb-containing Cu-Zr-Al based bulk metallic glasses

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Transactions of Nonferrous metals Society of China 2013年第7期23卷 2037-2041页

作者： m.ABBASI r.GHOLAmIPOUr F.shahri Faculty of Engineering and High-Tech. Iran University of Industries and MinesTehranIran Iranian research Organization for Science and Technology (IrOST) TehranIran

mechanical properties of （Cu50Zr43Al7）100 Nbx （x=0,1,3,6,9） bulk metallic glasses rods with a diameter of 2.5 mm prepared by suction casting method were studied. The results of uniaxial compression tests at room temperture show that the best mechanical properties of 2.8% and 1.98 GPa for plastic strain and fracture strength, respectively, in the sample with x=3. microstructure, fracture surface and shear bands of the samples were observed by SEm and XrD methods.

关键词： bulk metallic glass microstructure shear bands mechanical properties

Directivity Effect on PGV Attenuation relationships in Silakhor Earthquake （2006, mw6.1）

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Journal of Civil Engineering and Architecture 2011年第12期5卷 1117-1125页

作者： Katayoun Behzadafshar Abbas Abbaszadeh shahri Physics Department lslamic Azad University Shahr-e-Rey Unit Iran Geophysics Department Islamic Azad University Hamedan Branch Iran

rupture directivity effect causes spatial variation in strong ground motion parameters. It causes difference between the strike- normal （V.） and strike-parallel （Vp） components of horizontal ground motion amplitudes. These variations become significant for strong ground motion velocity and the authors have developed a modification to define directivity effect factor to account for the effect of rupture directivity in empirical velocity attenuation relations which are based on modeling Silakhor earthquake, using finite element method by ANSYS. The ground motion parameters that are modified include ratio of Vn/Vp component of horizontal velocity and Vn component to average horizontal velocity （V）. The ratio of Vn to Vp is large in both the forward directivity direction, where velocity is larger, and in the backward directivity direction, where velocity is smaller. Therefore the authors expected that the Vn/Vp was mainly controlled by directivity angle. Also the variation of fault normal velocity to average horizontal velocity ratio by directivity angle （0） is defined from earthquake modeling. It shows Vn/V is controlled by directivity angle, distance between the site, epicenter and rupture length. This ratio has the same trend in Silakhor earthquake strong ground velocity data. In this paper the equation for Vn/Vp variations by directivity angle is recommended. The authors used Somervill et al. （1997） directivity model parameters as （r/L） cos2 ~ to define directivity effect on Vn/V ratio and therefore directivity factor is determined to account in near field empirical strong ground velocity attenuation relationships.

关键词： Directivity Silakhor earthquake velocity attenuation relationships

The Adsorption of Copper from Aqueous Solutions Using Acrylamide-Grafted Cellulose

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Journal of Environmental Science and Engineering 2010年第3期4卷 25-31页

作者： m.m. shahri m.B. Ahmad m.J. Haron m.Z.A. rahman Department of Chemistry Faculty of Science University Putra Malaysia UPM-Serdang 43400 Malaysia Centre for Academic Development University Putra Malaysia UPM-Serdang 43400 Malaysia

In the present study, the aptitudes of acrylamide grafted cellulose to remove Cu（Ⅱ） ions from aqueous solutions were investigated. The preparation process was carried out through graft copolymerization of acrylamide onto cellulose, using ceric ammonium nitrate as an initiator. Fourier transform Infrared spectroscopy was used to confirm and characterization poly acrylamide-grafted cellulose formation. Batch experiments of Cu（Ⅱ） ions adsorption on the grafted cellulose adsorbent were performed. Effects of initial pH of the solution, contact time and initial Cu（Ⅱ） concentration on the adsorption of Cu（Ⅱ） were studied. The maximum adsorption of Cu（Ⅱ） ion on grafted cellulose is observed 90 mg/g at the initial pH of 6. Equilibrium time was reached within 3h. Kinetic data were analyzed using the pseudo-first-order, pseudo-second-order equations. The data fitted very well to the pseudo-second-order rate expression. The equilibrium data for adsorption isotherms of these metal ions on grafted cellulose were obtained using the Langmuir and Freundlich models and the Langmuir model was obtained to be in better correlation with the experimental data. The results showed that acrylamide-g-cellulose developed in this study could be an economical and effective adsorbent for application in removal of copper ion from water and waste waters.

关键词： Adsorption Cu(Ⅱ) cellulose kinetics isotherm.