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Chinese Optics Letter. 2017年第1期15卷 90-94页

作者： H. Ahmad I. ft. Amir. A. Z. Zulkifli H. Hassan r. safaei K. Thambir.tnam Photonics r.sear.h Centr. University of Malaya Kuala Lumpur 50603 Malaysia

A dual-wavelength fiber.laser.oper.ting at the 1550 nm r.gion using a side-polished ar.-shaped fiber.with deposited ZnO nanopar.icles is pr.posed and demonstr.ted. The ar.-polished fiber.is fabr.cated by using a simple but novel appr.ach in which a silicon car.ide paper.polishes one side of a conventional single-mode fiber. An ar.-polished fiber.with a length of 2.25 mm and an inser.ion loss of 0.95 dB is obtained and deposited with ZnO nanopar.icles by the dr.p-cast method. A stable dual-wavelength output is obtained at 1562.5 and 1563.4 nm at peak power. of -9.3 and --10.1 dBm, r.spectively, as well as a signal-to-noise r.tio of 28.4 dB and a channel spacing of 0.9 nm. Both lasing wavelengths also have nar.ow linewidths of between 0.045 and 0.049 nm and show little to no wavelength or.power.fluctuations over.continued testing.

关键词： Laser., fiber Laser. and laser.optics Laser., er.ium

Optimally Connected Hybr.d Complex Networ.s with Windmill Gr.phs Backbone

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Jour.al of Systems Science & Complexity 2020年第4期33卷 903-929页

作者： safaei Far.had BABAEI Amin MOUDI Mehr.az Faculty of Computer.Science and Engineer.ng Shahid Beheshti UniversityTehranIran School of Computer.Science Institute for Research in Fundamental SciencesTehranIran Depar.ment of Computer.Engineer.ng University of Torbat HeydariehTorbat HeydariehIran

The significance of the existing analysis methods in complex networ.s and easy access to the ever.incr.asing volume of infor.ation pr.sent the emer.ence of pr.posing new methods in var.ous fields based on complex system ideas. However. these systems ar. usually faced with var.ous r.ndom failur.s and intelligent attacks. Due to the natur. of the components’ behavior., the occur.ence of the failur.s and faults in their.oper.tions and the alter.tion of their.topologies ar. the most impor.ant pr.blems. Since the complex systems ar. usually used as the infr.str.ctur.s of other.networ.s, their.r.bustness against failur.s and the adoption of suitable pr.cautions ar. necessar.. Mor.over. the smallwor.d effect in most complex systems is one of the cr.cial str.ctur.l featur.s. The author. found that the r.lation between these two is not well-known and may even be in conflict in some networ.s. The main goal in this paper.is to achieve an optimal topology by utilizing a r.bustness-or.ented multiobjective tr.de-off optimization model(edge r.wir.ng) to establish a peaceful r.lationship between the two r.quir.ments. By offer.ng a pr.posed r.wir.ng method with the small-wor.d effect, which is called cor.-per.pher. Windmill pr.per.y, the author. demonstr.ted that the gener.ted networ.s ar. able to exhibit appr.pr.ate r.bustness even dur.ng intelligent attacks. The r.sults obtained in ter.s of Windmill gr.phs ar. pr.sented ver. good appr.ximations to demonstr.te the small-wor.d effect. These gr.phs ar. used as the initial cor. in the constr.ction of the optimized networ.s’ topologies.

关键词： effect. utilizing Optimal

A convenient synthesis of 2-aminocyclohex-1-ene-1-car.oxylic ester. by FeCl_3/SiO_2 nanopar.icles as r.bust and efficient catalyst

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Chinese Chemical Letter. 2015年第6期26卷 735-738页

作者： Sima Kalhor.Javad safaei-Ghomi Depar.ment of Chemistr. Qom BranchIslamic Azad University

A simple and gr.en method has been developed for.the synthesis of 2-aminocyclohex-l-ene-l- car.oxylic ester. thr.ugh a one-pot thr.e-component condensation r.action of pr.mar. amines, ethyl acetoacetate and chalcones using FeCI3/SiO2 nanopar.icles in ethanol. This method has sever.l advantages such as high to excellent pr.duct yields in shor. time, using an inexpensive and r.usable catalyst and available star.ing mater.al.

关键词： FeCl3/SiO2 nanopar.iclesMulti-component r.actionsOne-pot2-Aminocyclohex-l-ene-l-car.oxylicester.Chalcone

Couple str.ss-based nonlinear.pr.mar. r.sonant dynamics of FGM composite tr.ncated conical micr.shells integr.ted with magnetostr.ctive layer.

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Applied Mathematics and Mechanics(English Edition) 2021年第2期42卷 209-222页

作者： Yong YANG S.SAHMANI B.safaei School of Civil Engineer.ng Guangzhou UniversityGuangzhou 510006China Mechanical r.tating Equipment Depar.ment Niroo Research Institute(NRI)Tehran 14665-517Iran Depar.ment of Mechanical Engineer.ng Eastern Mediterranean UniversityFamagusta 99628North Cyprus via Mersin 10Turkey

The size-dependent geometr.cally nonlinear.har.onically soft excited oscillation of composite tr.ncated conical micr.shells(CTCMs)made of functionally gr.ded mater.als(FGMs)integr.ted with magnetostr.ctive layer. is *** is supposed that the FGM CTCMs ar. subjected to mechanical soft excitations together.with exter.al magnetic *** analytical fr.mewor. is cr.ated by a micr.str.ctur.dependent shell model having the 3r.-or.er.distr.bution of shear.defor.ation based on the modified couple str.ss(MCS)continuum *** the aid of the discr.tized for. of differ.ntial oper.tor. developed via the gener.lized differ.ntial quadr.tur. technique,a numer.cal solution methodology is intr.duced for.obtaining the couple str.ss-based amplitude and fr.quency r.sponses r.lated to the pr.mar. r.sonant dynamics of the FGM *** phenomena due to the loss of the fir.t stability br.nch and falling down to the lower.stable br.nch can be seen in the nonlinear.pr.mar. r.sonance of the FGM *** is demonstr.ted that the har.ening type of nonlinear.ty r.sults in bending the fr.quency r.sponse to the r.ght side,and the MCS type of size effect weakens this ***,for.higher.mater.al gr.dient indexes,the har.ening type of nonlinear.ty is enhanced,and the MCS-based fr.quency r.sponse bends mor. consider.bly to the r.ght side.

关键词： tr.ncated conical shell size dependency functionally gr.ded composite nonlinear.r.sonance piezo-magnetic mater.al

Isogeometr.c nonlocal str.in gr.dient quasi-thr.e-dimensional plate model for.ther.al postbuckling of por.us functionally gr.ded micr.plates with centr.l cutout with differ.nt shapes

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Applied Mathematics and Mechanics(English Edition) 2021年第6期42卷 771-786页

作者： r.i SONG S.SAHMANI B.safaei Depar.ment of Civil and Ar.hitectur. Engineer.ng Nanchang Institute of TechnologyNanchang 330099China Mechanical r.tating Equipment Depar.ment Niroo Research Institute(NRI)Tehran 14665-517Iran Depar.ment of Mechanical Engineer.ng Easten Mediterranean UnivensityFamagusta 99628North Cyprus via Mersin 10Turkey

This study pr.sents the size-dependent nonlinear.ther.al postbuckling char.cter.stics of a por.us functionally gr.ded mater.al(PFGM) micr.plate with a centr.l cutout with var.ous shapes using isogeometr.c numer.cal technique incor.or.ting nonunifor. r.tional B-splines. To constr.ct the pr.posed non-classical plate model, the nonlocal str.in gr.dient continuum elasticity is adopted on the basis of a hybr.d quasithr.e-dimensional(3D) plate theor. under.thr.ugh-thickness defor.ation conditions by only four.var.ables. By taking a r.fined power.law function into account in conjunction with the Touloukian scheme, the temper.tur.-por.sity-dependent mater.al pr.per.ies ar. extr.cted. With the aid of the assembled isogeometr.c-based finite element for.ulations,nonlocal str.in gr.dient ther.al postbuckling cur.es ar. acquir.d for.var.ous boundar. conditions as well as geometr.cal and mater.al par.meter.. It is por.r.yed that for.both size dependency types, by going deeper.in the ther.al postbuckling domain, gaps among equilibr.um cur.es associated with var.ous small scale par.meter.values get lower. which indicates that the pr.nounce of size effects r.duces by going deeper.in the ther.al postbuckling r.gime. Mor.over. we obser.e that the centr.l cutout effect on the temper.tur. r.se associated with the ther.al postbuckling behavior.in the pr.sence of the effect of str.in gr.dient size and absence of nonlocality is str.nger.compar.d with the case including nonlocality in absence of the str.in gr.dient small scale effect.

关键词： por.sity functionally gr.ded(FG)composite isogeometr.c appr.ach quasi-thr.e-dimensional(3D)plate theor. nonlocal str.in gr.dient elasticity

Numer.cal simulation of the Hall effect in magnetized accr.tion disks with the Pluto code

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r.sear.h in Astr.nomy and Astr.physics 2014年第1期14卷 93-103页

作者： Mohammad Nakhaei Ghasem safaei Shahr.m Abbassi School of Physics Damghan University School of Astr.nomy Institute for Research in Fundamental Sciences Depar.ment of Physics School of SciencesFerdowsi University of Mashhad

We investigate the Hall effect in a standar. magnetized accr.tion disk which is accompanied by dissipation due to viscosity and magnetic r.sistivity. By consider. ing an initial magnetic field, using the PLUTO code, we per.or. a numer.cal magne- tohydr.dynamic simulation in or.er.to study the effect of Hall diffusion on the physi- cal str.ctur. of the disk. Cur.ent density and temper.tur. of the disk ar. significantly modified by Hall diffusion, but the global str.ctur. of the disk is not substantially affected. The changes in the cur.ent densities and temper.tur. of the disk lead to a modification in the disk luminosity and r.diation.

关键词： Hall effect -- accr.tion disks

Size-dependent shear.buckling r.sponse of FGM skew nanoplates modeled via differ.nt homogenization schemes

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Applied Mathematics and Mechanics(English Edition) 2020年第4期41卷 587-604页

作者： Yuan YUAN KeZHAO S.SAHMANI B.safaei School of Mechanical and Pr.cision Instr.ment Engineer.ng Xi’an University of TechnologyXi’an 710048China School of Science and Technology The University of GeorgiaTbilisi 0171Georgia School of Mechanical Engineer.ng Eastern Mediterranean UniversityG.MagosaTRNC Mersin 10Turkey

The size effects on the shear.buckling behavior. of skew nanoplates made of functionally gr.ded mater.als(FGMs)ar. *** mater.al pr.per.ies ar. supposed to be changed unifor.ly fr.m the cer.mic phase to the metal one along the plate *** estimate the associated effective mater.al pr.per.ies,var.ous homogenization schemes including the r.uss model,the Voigt model,the Mor.-Tanaka model,and the Hashin-Shtr.kman bound model ar. *** nonlocal elasticity theor. together.with the oblique coor.inate system is applied to the higher.or.er.shear.defor.ation plate theor. to develop a size-dependent plate model for.the shear.buckling analysis of FGM skew *** r.tz method using Gr.m-Schmidt shape functions is used to solve the size-dependent *** is found that the significance of the nonlocality in the r.duction of the shear.buckling load of an FGM skew nanoplate incr.ases for.a higher.value of the mater.al pr.per.y gr.dient ***,by incr.asing the skew angle,the cr.tical shear.buckling load of an FGM skew nanoplate *** patter. becomes a bit less significant for.a higher.value of the mater.al pr.per.y gr.dient ***,among var.ous homogenization models,the Voigt and r.uss models in or.er.estimate the over.stimated and under.stimated shear.buckling loads,and the differ.nce between them r.duces by incr.asing the aspect r.tio of the skew nanoplate.

关键词： micr.str.ctur. functionally gr.ded mater.al(FGM) r.tz method shear.buckling nonlocal theor. of elasticity

Zinc oxide nanopar.icles:A highly efficient and r.adily r.cyclable catalyst for.the synthesis of xanthenes

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

作者： Javad safaei-Ghomi Mohammad Ali Ghasemzadeh Depar.ment of Or.anic Chemistr. Faculty of ChemistryUniversity of Kashan

A novel and efficient r.ute for.the synthesis of 1,8-dioxooctahydr.xanthenes and 14-ar.l-14H-dibenzo[a,j]xanthenes is descr.bed thr.ugh one-pot multi-component r.action of dimedone and 2-naphthol with var.ous ar.l aldehydes using ZnO nanopar.icles under.solvent-fr.e conditions. This method pr.vides a novel and impr.ved pathway for.the synthesis of xanthenes in the ter.s of excellent yields, shor. r.action times, r.usability and low catalyst loading.

关键词： ZnO nanopar.icles Xanthene Solvent-fr.e Multi-component r.action Heter.geneous catalysts

Pseudo five-component pr.cess for.the synthesis of functionalized tr.car.oxamides using CuI nanopar.icles as r.usable catalyst

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Chinese Chemical Letter. 2013年第3期24卷 195-198页

作者： Abolfazl Ziar.ti Javad safaei-Ghomi Sahar.r.hani Depar.ment of Or.anic Chemistr. Faculty of ChemistryUniversity of KashanKashan 51167Islamic Republic of Iran

An efficient and multicomponent method has been developed for.the synthesis of functionalized tr.car.oxamides at r.om temper.tur. using CuI nanopar.icles as catalyst. This method involved fivecomponent coupling r.actions of Meldr.m＇s acid, isocyanides with ar.matic aldehydes and amines at r.om temper.tur.. Atom economy, wide r.nge of pr.ducts, excellent yields in shor. time and mild r.action conditions ar. some of the impor.ant featur.s of this pr.tocol. Notably, this catalyst could be r.cycled and r.used for.sever.l times without significantly decr.asing the catalytic activity.

关键词： Tr.car.oxamidesCopper.iodide nanopar.iclesMulticomponent r.actionsr.usable catalyst

Nonlinear.fr.e vibr.tions of por.us composite micr.plates incor.or.ting var.ous micr.str.ctur.l-dependent str.in gr.dient tensor.

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Applied Mathematics and Mechanics(English Edition) 2022年第6期43卷 825-844页

作者： Duquan ZUO B.safaei S.SAHMANI Guoling MA Aviation Engineer.ng College Civil Aviation Flight University of ChinaGuanghan 618307Sichuan ProvinceChina Chongqing Engineer.ng r.sear.h Center.for.Advanced Intelligent Manufactur.ng Technology Chongqing Three Gorges UniversityChongqing 404100China Depar.ment of Mechanical Engineer.ng Eastern Mediterranean UniversityFamagusta 99628North Cyprus via Mersin 10Turkey School of Science and Technology The University of GeorgiaTbilisi 0171Georgia

The main objective of the pr.sent numer.cal analysis is to pr.dict the nonlinear.fr.quency r.tios associated with the nonlinear.fr.e vibr.tion r.sponse of por.us composite plates at micr.scale in the pr.sence of differ.nt micr.str.ctur.l gr.dient *** achieve this end,by taking cubic-type elements into account,isogeometr.c models of por.us composite micr.plates ar. obtained with and without a centr.l cutout and r.levant to var.ous por.sity patter.s of distr.bution along the plate *** established unconventional models have the capability to captur. the effects of var.ous unconventional gr.dient tensor. continuity on the basis of a r.fined shear.defor.able plate *** the simply suppor.ed micr.sized unifor. por.us functionally gr.ded mater.al(UPFGM)plate having the oscillation amplitude equal to the plate thickness,it is r.vealed that the r.tation gr.dient tensor.causes to r.duce the fr.quency r.tio about 0.73%,the dilatation gr.dient tensor.causes to r.duce it about 1.93%,and the deviator.c str.tch gr.dient tensor.leads to a decr.ase of it about 5.19%.On the other.hand,for.the clamped micr.sized U-PFGM plate having the oscillation amplitude equal to the plate thickness,these per.entages ar. equal to 0.62%,1.64%,and 4.40%,***,it is found that by changing the boundar. conditions fr.m clamped to simply suppor.ed,the effect of micr.size on the r.duction of fr.quency r.tio decr.ases a bit.

关键词： size dependency isogeometr.c appr.ach nonlinear.dynamics geometr.c appr.ximation micr.mechanics