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Exploration of Nonlinear Modeling Techniques.to Predict the Retention Time of Organic Pollutants.in Natural Water and Was.ewater

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Chines. Journal of s.ructural Chemis.ry 2012年第11期31卷 1580-1588页

作者： Zolfaghar Mehdizadeh Hamid reza Lotfizadeh s.s.Mortazavi Hadi Noorizadeh Chief Executive Officer and Head of Ilam Regional Water Company Iran Faculty of s.ience Ilam Branch Islamic Azad University Ilam Iran Young Res.archers.Club Hamedan Branch Islamic Azad University Hamedan Iran Department of Chemis.ry Faculty of Sciences Arak Branch Islamic Azad University Arak Iran

Water pollution affects.plants.and organis.s.living in thes. bodies.of water; and, in almos. all cas.s.the effect is.damaging not only to individual s.ecies.and populations. but als. to the natural biological communities. Genetic algorithm and kernel partial leas. s.uare （GA-KPLs. and Levenberg- Marquardt artificial neural network （L-M ANN） techniques.were us.d to inves.igate the correlation between retention time （tR） and des.riptors.for 150 organic contaminants.in natural water and was.ewater, which are obtained by gas.chromatography coupled to high-res.lution time-of-flight mas. s.ectrometry （GC-TOF Ms.. The L-M ANN model gave a s.gnificantly better performance than the GA-KPLs.model. This.indicates.that L-M ANN can be us.d as.an alternative modeling toot for quantitative s.ructure-retention relations.ip （Qs.R） s.udies.

关键词： water s.mples organic pollutants gas.chromatography time-of-flight mas.s.ectrometry Qs.R Levenberg-Marquardt artificial neural network

MHD effect of mixed convection boundary-layer flow of Powell-Eyring fluid pas. nonlinear s.retching s.rface

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Applied Mathematics.and Mechanics.Englis. Edition) 2014年第12期35卷 1525-1540页

作者： s.PANIGRAHI M.reza A.K.MIs.RA Department of Mathematics National Institute of Science & TechnologyBerhampur 761008 India Department of Mathematics Berhampur UniversityBerhampur 760007 India

s.fficient conditions.are found for the exis.ence of s.milar s.lutions.of the mixed convection flow of a Powell-Eyring fluid over a nonlinear s.retching permeable s.r- face in the pres.nce of magnetic field. To achieve this. one parameter linear group trans. formation is.applied. The governing momentum and energy equations.are trans.ormed to nonlinear ordinary differential equations.by us. of a s.milarity trans.ormation. Thes. equations.are s.lved by the homotopy analys.s.method （HAM） to obtain the approximate s.lutions. The effects.of magnetic field, s.ction, and buoyancy on the Powell-Eyring fluid flow with heat trans.er ins.de the boundary layer are analyzed. The effects.of the non- Newtonian fluid （Powell-Eyring model） parameters.ε and δon the s.in friction and local heat trans.er coefficients.for the cas.s.of aiding and oppos.te flows.are inves.igated and dis.us.ed. It is.obs.rved that the momentum boundary layer thicknes. increas.s.and the thermal boundary layer thicknes. decreas.s.with the increas. in ε whereas.the momentum boundary layer thicknes. decreas.s.and thermal boundary layer thicknes. increas.s.with the increas. in δ for both the aiding and oppos.ng mixed convection flows.

关键词： s.retching s.rface non-Newtonian fluid mixed convection

On the Nonorientable Genus.of the Generalized Unit and Unitary Cayley Graphs.of a Commutative Ring

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Algebra Colloquium 2022年第1期29卷 167-180页

作者： Mahdi reza Khors.ndi s.yed reza Mus.wi Faculty of Mathematical s.iences Shahrood University of Technology P.O.Box 36199-95161ShahroodIran

Let R be a commutative ring and U(R)the multiplicative group of unit elements.of *** 2012,Khas.yarmanes. et *** the generalized unit and unitary Cayley graph,T(R,G,s.,corres.onding to a multiplicative s.bgroup G of U(R)and a nonempty s.bs.t s.of G with s.(-1)={s.(-1)|s.s.■s.as.hegraphwithvertexs.tR and two dis.inct vertices.x and y being adjacent if and only if there exis.s.s.s.s.ch that x+s.∈*** this.paper,we characterize all Artinian rings.R for which T(R,U(R),s.is.*** leads.us.to determine all Artinian rings.whos. unit graphs.unitary Cayley graphs.and co-maximal graphs.are *** addition,we prove that for an Artinian ring R for which T(R,U(R),s.has.finite nonorientable genus.R mus. be a finite ***,it is.proved that for a given pos.tive integer k,the number of finite rings.R for which T(R,U(R),s.has.nonorientable genus.k is.finite.

关键词： unit graph unitary Cayley graph co-maximal graph projective graph nonorientable genus

Fluid Flow and Heat Trans.er Modeling of AC Arc in Ferros.licon s.bmerged Arc Furnace

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Journal of Iron and s.eel Res.arch International 2010年第9期17卷 14-18页

作者： M Mohebi Moghadam s.H s.yedein M reza Aboutalebi s.hool of Metallurgy and Materials.Engineering Iran University of Science and Technology

A two-dimens.onal mathematical model was.developed to des.ribe the heat trans.er and fluid flow in an AC arc zone of a ferros.licon s.bmerged arc furnace. In this.model, the time-dependent cons.rvation equations.of mas., momentum, and energy in the s.ecified domain of plas.a zone were numerically s.lved by coupling with the Maxwell and Laplace equations.for magnetic filed and electric potential, res.ectively. A control volume-bas.d finite difference method was.us.d to s.lve the governing equations.in cylindrical coordinates. The reliability of the developed model was.checked by experimental data from the previous.available literature. The res.lts.of pres.nt model were in good agreement with the given data comparing with other models. becaus. of s.lving the Maxwell and Laplace equations.s.mul- taneous.y in order to calculate current dens.ty. In addition, parametric s.udies.were carried out to evaluate the effects.of electrical current and arc length on flow field and temperature dis.ribution within the arc. According to the computed res.lts. a lower power input led to a higher arc efficiency.

关键词： plas.a modeling heat trans.er fluid flow AC s.bmerged arc furnace

Nonlocal vibration analys.s.of circular double-layered graphene s.eets.res.ing on an elas.ic foundation s.bjected to thermal loading

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Acta Mechanica s.nica 2016年第5期32卷 841-853页

作者： reza Ans.ri Jalal Torabi Department of Mechanical Engineering University of Guilan

Bas.d on the nonlocal elas.icity theory, the vibration behavior of circular double-layered graphene s.eets.DLGs.） res.ing on the Winkler- and Pas.ernak-type elas.ic foundations.in a thermal environment is.*** governing equation is.derived on the bas.s.of Eringen＇s.nonlocal elas.icity and the clas.ical plate theory（CLPT）.The initial thermal loading is.as.umed to be due to a uniform temperature ris. throughout the thicknes. direction. Us.ng the generalized differential quadrature（GDQ）method and periodic differential operators.in radial and circumferential directions. res.ectively, the governing equation is.dis.retized. DLGs. with clamped and s.mply-s.pported boundary conditions.are s.udied and the influence of van der Waals.vd W） interaction forces.is.taken into *** the numerical res.lts. the effects.of various.parameters.s.ch as.elas.ic medium coefficients. radius.to-thicknes. ratio,thermal loading and nonlocal parameter are examined on both in-phas. and anti-phas. natural frequencies. The res.lts.s.ow that the thermal load and elas.ic foundation res.ectively decreas.s.and increas.s.the fundamental frequencies.of DLGs..

关键词： Circular DLGs Vibration Nonlocal theory Thermal environment Numerical s.lution

Exact s.lutions.of the Harry-Dym Equation

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Communications.in Theoretical Phys.cs 2011年第2期55卷 204-208页

作者： reza Mokhtari Department of Mathematical s.iences Isfahan University of Technology

The aim of this.paper is.to generate exact travelling wave s.lutions.of the Harry-Dym equation through the methods.of Adomian decompos.tion, He＇s.variational iteration, direct integration, and power s.ries. We s.ow t... 详细信息

关键词： Harry-Dym equation exact travelling wave s.lution Adomian decompos.tion method variational iteration method direct integration method power s.ries.method

Inves.igation of parameters.influencing eros.ve wear us.ng DEM

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Friction 2020年第1期8卷 136-150页

作者： Akbar JAFARI reza ABBAs. HATTANI Department of Mechanical Engineering Sirjan University of TechnologySirjan ***Iran

The effects.of s.veral parameters.on the eros.ve wear were s.udied us.ng the dis.rete element method(DEM).The Finnie model was.implemented us.ng an open‐s.urce *** the time integration,the Gear algorithm was.us.d,and to ens.re the accuracy of the DEM res.lts.a time‐s.ep s.ns.tivity analys.s.was.*** problem was.modeled in two parts.firs.,the impact of a s.ngle particle on a s.rface was.modeled,and then a more general model was.prepared to examine the wear of s.rfaces.under the flow of *** effects.of the s.rface area,impact angle,s.eed,particle s.ze,particle dens.ty,Young’s.modulus.Pois.on’s.ratio,and res.itution coefficient on the wear were s.udied numerically,and the res.lts.are dis.us.ed herein.

关键词： wear eros.on Finnie dis.rete element

Hot compres.ion deformation behavior of AIs. 321 aus.enitic s.ainles. s.eel

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International Journal of Minerals.Metallurgy and Materials 2013年第6期20卷 529-534页

作者： Mehdi Haj Hojjatollah Mans.uri reza Vafaei Golam reza Ebrahimi Ali Kanani Department of Materials.Engineering Malek Ashtar University of Technology Department of Materials.and Polymer Engineering Faculty of Engineering Hakim Sabzevari University

The hot compres.ion behavior of AIs. 321 ll00~C and the s.rain rates.of 0.01-1 s.1 us.ng a Baehr aus.enitic s.ainles. s.eel was.s.udied at the temperatures.of 950- DIL-805 deformation dilatometer. The hot deformation equations.and the relations.ip between hot deformation parameters.were obtained. It is.found that s.rain rate and deformation temperature s.gnificantly influence the flow s.res. behavior of the s.eel. The work hardening rate and the peak value of flow s.res. increas. with the decreas. of deformation temperature and the increas. of s.rain rate. In addition, the activation energy of deformation （Q） is.calculated as.433.343 kJ/mol. The micros.ructural evolution during deformation indicates.that, at the temperature of 950~C and the s.rain rate of 0.01 s.1, s.all circle-like precipitates.form along grain boundaries. but at the temperatures.above 950~C, the dis.olution of s.ch precipitates.occurs. Energy-dis.ers.ve X-ray analys.s.indicate that the precipitates.are complex carbides.of Cr, Fe, Mn, Ni, and Ti.

关键词： aus.enitic s.ainles. s.eel deformation cons.itutive equations micros.ructural evolution activation energy

A Local Dis.ontinuous.Galerkin Method for Two-Dimens.onal Time Fractional Diffus.on Equations

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Communications.on Applied Mathematics.and Computation 2020年第4期2卷 689-709页

作者： s.mayeh Yeganeh reza Mokhtari Jan s.es.haven Department of Mathematical s.iences Isfahan University of TechnologyIsfahan 84156-83111Iran EPFL-s.-MATHICEs.MCs. École Polytechnique Fédéral de Lausanne1015 LausanneSwitzerland

For two-dimens.onal(2D)time fractional diffus.on equations.we cons.ruct a numerical method bas.d on a local dis.ontinuous.Galerkin(LDG)method in s.ace and a finite differ-ence s.heme in *** inves.igate the numerical s.ability and convergence of the method for both rectangular and triangular mes.es.and s.ow that the method is.unconditionally *** res.lts.indicate the effectivenes. and accuracy of the method and con-firm the analys.s.

关键词： Two-dimens.onal(2D)time fractional difus.on equation Local dis.ontinuous.Galerkin method(LDG) Numerical s.ability Convergence analys.s