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Journal of Semiconductors 2013年第8期34卷 1-7页

作者： m.r.Fadavieslam m.m.Bagheri-mohagheghi School of Physics Damghan University

Thin films of tin selenide（Sn_xSe_y） with an atomic ratio of r =[y/x]= 0.5,1 and 1.5 were prepared on a glass substrate at T = 470℃using a spray pyrolysis *** initial materials for the preparation of the thin films were an alcoholic solution consisting of tin chloride（SnCl_4·5H_2O） and selenide acide（H_2SeO_3）.The prepared thin films were characterized by X-ray diffraction（XrD）,scanning electron microscopy,scanning tunneling microscopy,scanning helium ion microscopy,and UV-vis *** photoconductivity and thermoelectric effects of the Sn_xSe_ythin films were then *** Sn_xSe_y thin films had a polycrystalline structure with an almost uniform surface and cluster type *** increasing atomic ratio of r in the films,the optical gap,photosensitivity and Seebeck coefficient were changed from 1.6 to 1.37 eV,0.01 to 0.31 and -26.2 to—42.7 mV/K （at T = 350 K）,*** addition,the XrD patterns indicated intensity peaks in r = 1 that corresponded to the increase in the SnSe and SnSe_2 phases.

关键词： thin film tin selenide spray pyrolysis optical band gap

On the Characterizability of the Automorphism Groups of Sporadic Simple Groups by Their Element Orders

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Acta mathematica Sinica,English Series 2004年第4期20卷 653-662页

作者： A.r.mOGHADDAmFAr A.r.ZOKAYI m.r.DArAFSHEH Department of mathematics Faculty of ScienceK.N.Toosi University of TechnologyP.O.Box 16315-1618TehranIran Department of mathematics and Computer Sciences Faculty of ScienceUniversity of TehranTehranIran

For G a finite group,π_e(G)denotes the set of orders of elements in *** Ω is a subset of the set of natural numbers,h(Ω)stands for the number of isomorphism classes of finite groups with the same set Ω of element *** say that G is k-distinguishable if h(π_(G))=krwise G is called ***,a 1-distinguishable group is called a characterizable *** is shown that if m is a sporadic simple group different from m_(12),m_(22),J_2,He,Suz,m^cL and O'N, then Aut(m)is charaeterizable by its dement *** is also proved that if m is isomorphic to m_(12),m_(22),He,Suz or O'N,then h(π_e(Aut(m)))∈{1,∞}.

关键词： Automorphism group Element orders Prime graph Sporadic simple groups

A rECOGNITION OF SImPLE GrOUPS PSL(3,q) BY THEIr ELEmENT OrDErS

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Acta mathematica Scientia 2004年第1期24卷 45-51页

作者： m.r.Darafsheh A.r.moghaddamfar A.r.Zokayi Department of mathematics and Computer Sciences Faculty of Science University of Tehran Tehran IranDepartment of Mathematics K. N. T University of TechnologyP.O. Boz 16315-1618 Tehuan IranDepartment of Mathematics K. N. T University of TechnologyP.O. Boz 16315-1618 Tehuan Iran

For any group G, denote byπe(G) the set of orders of elements in G. Given a finite group G, let h(πe (G)) be the number of isomorphism classes of finite groups with the same set πe(G) of element orders. A group G is called k-recognizable if h(πe(G)) = k rwise G is called non-recognizable. Also a 1-recognizable group is called a recognizable (or characterizable) group. In this paper the authors show that the simple groups PSL(3,q), where 3 mod 5) and (6, (q-1)/2) = 1, are recognizable.

关键词： Element order prime graph projective special linear group

A variational differential quadrature solution to finite deformation problems of hyperelastic shell-type structures:a two-point formulation in Cartesian coordinates

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Applied mathematics and mechanics(English Edition) 2022年第8期43卷 1219-1232页

作者： m.FArAJI-OSKOUIE r.ANSArI m.DArVIZEH Faculty of mechanical Engineering University of GuilanRasht3756Iran

A new numerical approach is presented to compute the large deformations of shell-type structures made of the Saint Venant-Kirchhoff and Neo-Hookean materials based on the seven-parameter shell theory.A work conjugate pair of the first Piola Kirchhoff stress tensor and deformation gradient tensor is considered for the stress and strain measures in the *** introducing the displacement vector,the deformation gradient,and the stress tensor in the Cartesian coordinate system and by means of the chain rule for taking derivative of tensors,the difficulties in using the curvilinear coordinate system are *** variational differential quadrature(VDQ)method as a pointwise numerical method is also used to discretize the weak form of the governing *** locking-free,the simple implementation,computational efficiency,and fast convergence rate are the main features of the proposed numerical *** well-known benchmark problems are solved to assess the *** results indicate that it is capable of addressing the large deformation problems of elastic and hyperelastic shell-type structures efficiently.

关键词： shell large deformation variational differential quadrature(VDQ)technique seven-parameter shell theory first Piola Kirchhoff stress tensor and deformation gradient tensor(P−F)formulation

Lattice expansion and smaller CuO_(x)CeO_(2-δ)particles formation by magnesium interaction for low temperature CO oxidation

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Journal of rare Earths 2021年第4期39卷 434-439页

作者： J.m.Waikar r.K.more N.r.Lavande P.m.more Department of Chemistry Institute of Chemical TechnologyMatungaMumbai400019India

A series of magnesia doped CuOxCeO_(2-δ)catalysts were prepared by co-precipitation followed by impregnation method and investigated for CO *** manuscript is devoted to explaining the role of mgO for the formation of active species on the CuOxCeO_(2-δ)*** improvement in catalytic activity is ascribed to the formation of various active species due to the interaction of magnesia with CuOxCeO_(2-δ).The catalysts were characterized by PXrD,N_(2)adsorption,H_(2)-TPr,XPS,SEm,EDS and HrTEm *** mg doped catalyst shows lattice expansion of ceria due to the formation of smaller Ce^(3+)species with oxygen *** mg-O bond also takes part in CO activation and oxidation,which results in the increase of CO *** mg doped CuOxCeO_(2-δ)catalyst shows improvement in low temperature activity compared with the CuOxCeO_(2-δ).

关键词： Adsorbed oxygen Lattice expansion Low temperature oxidation Ce^(3+) Cu^(+) rare earths

Flood basalt hosted palaeosols:Potential palaeoclimatic indicators of global climate change

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Geoscience Frontiers 2014年第6期5卷 791-799页

作者： m.r.G.Sayyed Department of Geology Poona College (University of Pune)CampPune 411 001MaharashtraIndia

Since continental sediments （in addition to the marine geological record） offer important means of deciphering environmental changes, the sediments hosted by the successive flows of the continental flood basalt provinces of the world should be treasure houses in gathering the palaeoclimatic data. Palaeosols developed on top of basalt flows are potentially ideal for palaeoenvironmental reconstructions because it is easy to determine their protolith geochemistry and also they define a definite time interval. The present paper summarizes the nature of the basalt-hosted palaeosols formed on the flood basalts provinces from different parts of the ~lobe havin~ different ages.

关键词： Continental flood basalts Palaeosols Weathering Palaeoclimates Global change

Subsidence history and forming mechanism of anomalous tectonic subsidence in the Bozhong depression, Bohaiwan basin

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Science China Earth Sciences 2007年第9期50卷 1310-1318页

作者： müLLEr r. Dietmar School of Geosciences University of Sydney Sydney NSW 2006 Australia

The Bozhong depression of the Bohaiwan basin belongs to a family of extensional basins in East China, but is quite different from other parts of the basin. The Cenozoic subsidence of the depression is controlled by a combination of lithospheric thinning and polycyclic strike-slip movements. Three episodic rifts have been identified, i.e. Paleocence-early Eocene, middle-late Eocene and Oligocene age. The depression underwent syn-rift and post-rift stages, but two episodic dextral movement events of the strike-slip faults modify the subsidence of the Bozhong depression since the Oligocene. The early dextral movement of the Tan-Lu fault associated with crustal extension resulted in accelerated subsidence during the time of deposition of the Dongying Formation with a maximum thickness of 4000 m. A late reactivation of dextral movement of the Tan-Lu fault began in late miocene (about 12 ma), which resulted in the intense subsidence of minghuazhen Formation and Quaternary. In addition, dynamic mantle convection-driven topography also accelerated the post-rift anomalous subsidence since the miocene (24.6 ma). Our results indicate that the primary control on rapid subsidence both during the rift and post-rift stages in the Bozhong depression originates from a combination of multiple episodic crustal extension and polycyclic dextral movements of strike-slip faults, and dynamic topography.

关键词： tectonic subsidence strike-slip dynamic topography Bozhong depression Bohaiwan basin

SOmE CONVOLUTION AND INCLUSION PrOPErTIES FOr SUBCLASSES OF mErOmOrPHIC p-VALENT FUNCTIONS INVOLVING INTEGrAL OPErATOr

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Acta mathematica Scientia 2013年第6期33卷 1749-1758页

作者： r.m.EL-ASHWAH Department of mathematics Faculty of ScienceDamietta University

making use of the linear operator Lp^m（λ,e）f（z）=1/z^p＋∞∑k=1[e/e＋λk]^m akz^k-p,where e〉0,λ〉0,p∈N,m∈N0=NUm,z∈U^＊ and f（z）∈∑p,we introduce two subclasses of meromorphic p-valent analytic functions ... 详细信息

关键词： analytic functions meromorphic functions multiplier transformations

Impact of carbon paper structural parameters on the performance of a polymer electrolyte fuel cell cathode via lattice Boltzmann method

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Acta mechanica Sinica 2020年第2期36卷 367-380页

作者： m.Nazemian G.r.molaeimanesh research Laboratory of Automotive Fluids and Structures Analysis Automotive Engineering SchoolIran University of Science and TechnologyTehran 16846-13114Iran

Polymer electrolyte fuel cells(PEFCs)being employed in fuel cell electric vehicles(FCEVs)are promising power generators producing electric power from fuel stream via porous *** of carbon paper gas diffusion layers(GDLs)applying in the porous electrodes can greatly affect the PEFC performance,especially at the cathode side where electrochemical reaction is more *** discover the role of carbon paper GDL structure on the mass transfer properties,different cathode electrodes with dissimilar structural parameters are simulated via lattice Boltzmann method(LBm).3D contours of oxygen and water vapor concentration through the GDL as well as the 2D contours of current density on the catalyst layer are illustrated and *** results indicate that the carbon fiber diameter has a negligible impact on the current density while the impact of carbon paper thickness and porosity is *** fact,increasing of carbon paper thickness or porosity leads to lack of cell performance.

关键词： Polymer electrolyte fuel cell(PEFC) Lattice Boltzmann method(LBm) microstructure reconstruction Carbon paper mass transfer properties

Physical Simulation of Hot Deformation and microstructural Evolution for 42Crmo4 Steel Prior to Direct Quenching

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Journal of Iron and Steel research International 2009年第6期16卷 47-51页

作者： A H meysami r Ghasemzadeh S H Seyedein m r Aboutalebi r Ebrahimi m Javidani Department of material Science and Engineering Iran University of Science and Technology Department of material Science and Engineering Sabzevar Tarbiat-Moallem University

Direct quenching and tempering （DQ-T） of hot rolled steel section has been widely used in steel mill for the sake of improvement of mechanical properties and energy saving. Temperature history and microstructural evolution during hot rolling plays a major role in the properties of direct quenched and tempered products. The mathematical and physical modeling of hot forming processes is becoming a very important tool for design and development of required products as well as predicting the microstructure and the properties of the components. These models were mostly used to predict austenite grain size （AGS）, dynamic, recta-dynamic and static recrystallization in the rods immediately after hot rolling and prior to DQ process. The hot compression tests were carried out on 42Crmo4 steel in the temperature range of 900-1 100 ℃ and the strain rate range of 0. 05-1 s^-1 in order to study the high tempera- ture softening behavior of the steel. For the exact prediction of flow stress, the effective stress-effective strain curves were obtained from experiments under various conditions. On the basis of experimental results, the dynamic recrystallization fraction （DrX）, AGS, hot deformation and activation energy behavior were investigated. It was found that the calculated results were in good agreement with the experimental flow stress and microstructure of the steel for different conditions of hot deformation.

关键词： 42Crmo4 steel hot compression test dynamic recrystallization hot deformation direct quenching physical simulation