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Computer modeling in Engineering & Sciences 2022年第3期130卷 1349-1369页

作者： m.R.Hematiyan b.Jamshidi m.mohammadi Department of mechanical Engineering Shiraz UniversityShiraz71936Iran Department of mechanical Engineering College of EngineeringShiraz BranchIslamic Azad UniversityShiraz71993Iran

The method of fundamental solutions(mFS)is a boundary-type and truly meshfree method,which is recognized as an efficient numerical tool for solving boundary value *** geometrical shape,boundary conditions,and applied loads can be easily modeled in the *** capability makes the mFS particularly suitable for shape optimization,moving load,and inverse ***,it is observed that the standard mFS lead to inaccurate solutions for some elastostatic problems with stress concentration and/or highly anisotropic *** thiswork,by a numerical study,the important parameters,which have significant influence on the accuracy of the mFS for the analysis of two-dimensional anisotropic elastostatic problems,are *** studied parameters are the degree of anisotropy of the problem,the ratio of the number of collocation points to the number of source points,and the distance between main and pseudo *** is observed that as the anisotropy of the material increases,there will be more errors in the *** is also observed that for simple problems,increasing the distance between main and pseudo boundaries enhances the accuracy of the results;however,it is not the case for complicated ***,it is concluded that more collocation points than source points can significantly improve the accuracy of the results.

关键词： meshfree method degree of anisotropy location of source points anisotropic elasticity least squares mFS

Opaque mineralogy as a Tracer of magmatic History of Volcanic Rocks: an Example from the Neogene-Quaternary Harrat Rahat Intercontinental Volcanic Field, North Western Saudi Arabia

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Acta Geologica Sinica(English Edition) 2013年第5期87卷 1281-1305页

作者： A.A.SUROUR A.m.b.mOUFTI Department of mineral Resources and Rocks Faculty of Earth SciencesKing Abdul Aziz University

The Neogene-Quaternary Harrat Rahat volcanic field is part of the major intercontinental Harrat fields in western Saudi Arabia. It comprises lava flows of olivine basalt and hawaiite, in addition to mugearite, benmorite, and trachyte that occur mainly as domes, tuff cones and lava flows. based on opaque mineralogy and mineral chemistry, the Harrat Rahat volcanic varieties are distinguished into Group I （olivine basalt and hawaiite） and Group II （mugearite, benmorite and trachyte）. The maximum forsterite content （-85） is encountered in zoned forsteritic olivine of Group I, whereas olivine of Group II is characterized by intermediate （Fo=50）, fayalitic （Fo=25） and pure fayalite in the mugearite, benmorite and trachyte, respectively. The more evolved varieties of Group II contain minerals that show enrichment of Fe2＋, mn2~ and Na~ that indicates normal fractional crystallization. The common occurrence of indicates that pS＋ becomes saturated in this coarse apatite with titanomagnetite in the benmorite rock variety and drops again in trachyte. Cr-spinel is recorded in Group I varieties only and the Cr# （0.5） suggests lherzolite as a possible restite of the Harrat Rahat volcanics. The plots of Cr# vs. the forsterite content （Fo） suggest two distinct trends, which are typical of mixing of two basaltic magmas of different sources and different degrees of partial melting. The bimodality of Harrat Rahat Cr-spinel suggests possible derivation from recycled mORb slab in the mantle as indicated by the presence of high-Al spinel. It is believed that the subcontinental lithospheric mantle was modified by pervious subduction process and played the leading role in the genesis of the Harrat Rahat intraplate volcanics. The trachytes of the Harrat Rahat volcanic field were formed most probably by melting of a lower crust at the mantle-crust boundary. The increase in fo2 causes a decrease in Cr203, and A1203, and a strong increase in the proportion of Fe3＋ and mg# of spinel crystallizin

关键词： Harrat Rahat intraplate volcanism Cr-spinel titanomagnetite Saudi Arabia

A Search on Dirac Equation

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Chinese Physics Letters 2007年第11期24卷 3024-3027页

作者： m. Kocak, b. Gonül Department of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Turkey

The solutions, in terms of orthogonal polynomials, of Dirac equation with analytically solvable potentials are investigated within a novel formalism by transforming the relativistic equation into a Schrodinger-like one. Earlier results are discussed in a unified framework, and some solutions of a large class of potentials are given.

关键词： coated conductor buffer layer self-epitaxy CeO2

The Effects of Chemical (isotropic) and Anisotropic Etching Processes on the Roughening of Nanocomposite Substrates

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Plasma Science and Technology 2010年第6期12卷 673-676页

作者： m.RADmILOVI-RADJENOVI b.RADJENOVI Institute of Physics

Simulation results of roughening of nanocomposite materials during both isotropic and anisotropic etching processes based on the level set method are presented. It is clearly shown that the presence of two phases with different etching rates affects the development of surface roughness and that some roughness characteristics obey simple scaling laws. In addition, certain scaling laws that describe the time dependence of the root mean square （rms） roughness w for various etching processes and different characteristics of the nanocomposite materials are determined.

关键词： nanocomposite roughness smoothing isotropic etching anisotropic etching

Remarks on Exact Solvability of Quantum Systems with Spatially Varying Effective mass

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Chinese Physics Letters 2005年第11期22卷 2742-2745页

作者： b. Goenül m. Kocak Department of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Türkiye

Within the frame of a novel treatment we make a complete mathematical analysis of exactly solvable onedimensional quantum systems with non-constant mass, involving their ordering ambiguities. This work extends the results recently reported in the literature and clarifies the relation between physically acceptable effective mass Hamiltonians.

关键词： DEPENDENT EFFECTIVE mASSES SUPERSYmmETRIC APPROACH SCHRODINGER-EQUATION PERTURbATION-THEORY POTENTIALS SEmICONDUCTORS STATES

Compocasting of A356-CNT composite

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Transactions of Nonferrous metals Society of China 2010年第9期20卷 1561-1566页

作者： b.AbbASIPOUR b.NIROUm AND S.m.mONIR VAGHEFI Department of materials Engineering Isfahan University of Technology

A356 aluminum alloys reinforced with carbon nano-tubes (CNTs) were produced by stir casting and compocasting routes and their microstructural characteristics and hardness were *** order to alleviate the problems associated with poor wettability, agglomeration and gravity segregation of CNTs in the melt, CNTs were introduced into the melts by injection of CNT deposited aluminum particles instead of raw *** particles with mean diameters of less than 100 μm were first deposited by CNTs using Ni-P electroless plating technique and then injected into the melt agitated by a mechanical *** slurry was subsequently cast at temperatures corresponding to full liquid as well as 0.15 and 0.30 solid *** results show that addition of CNTs to A356 matrix can significantly refine both full liquid and semi-solid cast *** of the samples is also significantly increased by addition of CNTs and A356-CNT composite cast at 0.3 solid fraction produces the highest hardness.

关键词： A356-CNT composite carbon nano-tube (CNT) compocasting electroless plating microstructure hardness

PROXImAL POINT ALGORITHm FOR mINImIZATION OF DC FUNCTION

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Journal of Computational mathematics 2003年第4期21卷 451-462页

作者： Wen-yuSun Raimundo.J.b.Sampaio m.A.b.Candido SchoolofmathematicsandComputerScience NanjingNormalUniversityNanjing2100g7China ProgramadePos-GraduacaoemInformaticaAplicada PontificiaUniversidadeCatolicadoParana(PUCPR)CEP:80215-g01CuritibaPRBrazil ProgramadePos-GraduacaoemInformaticaAplicada PontificiaUniversidadeCatolicadoParana(PUCPR)CEP:80215-g01CuritibaPRBrazil

In this paper we present some algorithms for minimization of DC function (difference of two convex functions). They are descent methods of the proximal-type which use the convex properties of the two convex functions separately. We also consider an approximate proximal point algorithm. Some properties of the ε-subdifferential and the ε-directional derivative are discussed. The convergence properties of the algorithms are established in both exact and approximate forms. Finally, we give some applications to the concave programming and maximum eigenvalue problems.

关键词： Nonconvex optimization Nonsmooth optimization DC function Proximal point algorithm ε-subgradient.

Suitability of lost cores in rheocasting process

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中国有色金属学会会刊：英文版 2010年第S3期20卷 948-953页

作者： H.mICHELS m.büNCK A.büHRIG-POLACZEK Giesserei-Institut RWTH Aachen Intzestraeβ5Aachen 52072Germany

When treated in pressure die casting processes the semi-solid aluminum alloys demand resilient cores which can bear the stress occurring during filling and the final pressure *** design of permanent cores is highly restricted in order to maintain *** cores provide the possibility of complex,undercut geometrical shapes which is mandatory for a variety of casting ***,eligible materials which show appropriate resilience and proper decomposition properties at the same time,and in the upper echelon of cost-effectiveness,are seldom *** the semi-solid process suited between HPDC and GDC regarding the core stress,several common and economically efficient lost core systems could be used.A selection of potentially suitable materials was identified and *** range of testing comprises widespread sand core-systems(amin-pur-coldbox and CO2-water-glass) as well as materials less commonly used,namely salt,plastic and *** types of conditioning are applied to enhance the surface *** mechanical properties of the sand cores are enhanced by different heat treatment methods during *** cores are tested producing a research component cast on a HPDC machine with semi-solid A356 slurry fabricated in the cooling channel *** cast component was analyzed regarding shape stability,core removability and surface as well as the structure *** results show the importance of the surface conditioning for the sand-cores while salt and zinc produce good parts comparable to the reference steel core quality.

关键词： aluminum semi-solid rheocasting cooling channel lost core sand salt zinc plastic

Epistasis and maternal Effect in Resistance to Puccinia coronata ***. avenae Eriks in Oats(Avena sp.)

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Agricultural Sciences in China 2010年第10期9卷 1462-1466页

作者： bnejdi F Hammami I Allagui m b Saadoun m el Gazzah m Laboratoire de Génétique et biométrie Faculté des Sciences de Tunis Université Tunis Institut National de la Recherche Agronomique de Tunisie(INRAT) Rue Hadi Karray

The objective of this paper was to investigate the mode of heredity for resistance in oats （Avena sp.） to crown rust caused by Puccinia coronata Cda. f. sp. avenae Eriks, Eight generations of 2 crosses were used to estimate genetic effects and narrow-sense heritability （NSH）. Separate generation means analysis （GmA） indicated a complex gene action controlling this trait with additive, dominance, epistatic and maternal effects （mE）. The genetic model which assumed no epistasis and no mE did not accurately describe the resistance to P. coronata. In both crosses, the digenic epistatic model with mE was sufficient to explain variation in generation means for isolate CRec58 and isolate CRec46. Additive dominance and epistatic components were negative in most cases, suggesting that gene effects contributed more to the resistance than to the susceptibility. The estimated values of NSH were 15-99% depending upon the cross and isolates. The results indicated that appropriate choice of maternal parent and recurrent selection would increase resistance to crown rust in oats.

关键词： epistasis heritability maternal effect resistance

bendable tube-shaped supercapacitor based on reduced graphene oxide and Prussian blue coated carbon fiber yarns for energy storage

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Journal of Energy Chemistry 2018年第3期27卷 866-873页

作者： mohd.Khalid Ana m.b.Honorato Department of macromolecular Science and Engineering Case Western Reserve University

Carbon fiber yarns（CFY） are promising as a new type of flexible building blocks for the construction of flexible architectures for the energy storage applications. The main hurdle with CFY is how to make them high energy and power capable by using economically and environmentally viable materials. Here,we report reduced graphene oxide（r GO） and Prussian blue（Pb） coated CFY, derived from a facile electrochemical process at room temperature for supercapacitor electrodes. The Pb coated CFY and r GO coated CFY electrodes exhibit the excellent gravimetric capacitance of 339 F/g and 160.2 F/g, respectively, in aqueous KCl electrolyte in three-electrode cell configuration. When we coupled these electrodes inside the flexible plastic tube and separated by the electrolyte wet filter paper in order to construct flexible architecture, the resulting device delivers excellent specific energy of 52.1 Wh/kg and 26.5 Wh/kg with offering specific power of 3100 W/kg and 14400 W/kg respectively, under a wide operating potential of1.8 V with excellent rate capability. The device shows high tolerance towards bending, and retained its efficiency to the capacitance after being bent at an angle of 360° for 200 bending cycles.

关键词： Carbon fiber yarns bendable supercapacitor Energy density Power density