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71.
This work examines the heat transfer properties of magnetohydrodynamic nanofluid flow. Through a similarity conversion, the leading structure of partial differential equations is changed to that of ordinary differential equations. A rigorous mathematical bvp4c methodology is used to generate numerical results. The purpose of this study is to characterize the different temperature, concentration, and velocity limitations on a nanofluid with a magnetic effect that is spinning. The findings for rotating nanofluid flow and heat transfer characteristics of nanoparticles are shown using graphs and tables. The influence of physical factors such as heat transfer rates and skin friction coefficients is studied. When the magnetic parameter M is raised, the velocity of the nanoliquid decreases. A rise in thermal radiation (Rd) causes the temperature graphs to grow substantially, although the concentration profiles exhibit the opposite tendency. The effect of the convective heat transfer factor Bi on temperature is shown to increase as Bi increases, but the concentration distribution decreases as Biot increases. 相似文献
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Abderrahim Houmat 《Acta Mechanica》2009,208(3-4):281-297
The nonlinear free vibration of a laminated composite annular elliptical plate with elliptically orthotropic plies is investigated. The effects of out-of-plane shear deformations, rotatory inertia and geometrical nonlinearity are taken into account. The problem is solved numerically using a new polynomially enriched sector elliptic p-element. The nonlinear equations of free motion are obtained using the harmonic balance method and solved iteratively by the linearized updated mode method. Results for the fundamental linear and nonlinear frequencies are obtained. Comparison is made with published results for a polar orthotropic annular plate and shows very good agreement. The minor semi-axis ratio, thickness ratio, moduli ratio, number of plies, layup sequence, and boundary conditions are shown to influence the hardening behavior. 相似文献
74.
M. Boulanouar 《Journal of Dynamical and Control Systems》2001,7(3):299-326
We study the streaming operator in slab domain with general Maxwell's boundary conditions described by linear boundary operators K+ and K–. We prove that the streaming operator generates a strongly continuous semigroup. We show that the positivity and irreducibility of the boundary operators imply the positivity and irreducibility of the generated semigroup. We establish the spectral properties of the streaming operator and characterize its spectral bound. Under the compactness of boundary operators, we explicitly give the essential type of the generated semigroup and describe its asymptotic behavior in the operator norm topology. 相似文献
75.
Hikmet Houichi Abderrahim Maazouz Boubaker Elleuch 《Polymer Engineering and Science》2015,55(8):1881-1888
A novel way using a polarized optical microscopy and statistical image analysis techniques for direct investigation of the crystallization kinetics and spherulitic morphology of poly (lactic acid) induced by casting process has been proposed. DSC analyses were carried out to explore the effect of drawing in thermal properties of PLA. We found that the rate of cold crystallization was sharply increased with draw ratio. Isothermal calorimetric results reveal that thin films crystallize slowly compared to sheets. Moreover, thin films don't fit the Avrami model demonstrating that more stretching may modify the crystallization kinetics of films. A comparison was made between pure PLA and stretched materials using Hoffman theory and giving a compiled view on the details of crystallization behavior with relation to stretch effect. At draw ratio 167, the growth rate reach its maximum and the crystallization rate go up exponentially. POM experiments showed the existence of two different spherulitic populations in thin films and two nucleation mechanisms was identified. Accordingly, the growth rate was found to be not linear with time. Furthermore, the X‐ray diffraction analyses showed the presence of α and α' crystal form in thin films contrarily to sheets with α form. POLYM. ENG. SCI., 55:1881–1888, 2015. © 2014 Society of Plastics Engineers 相似文献
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Ait hssi Abderrahim Amaterz Elhassan labchir Nabil Soussi Ahmed Elfanaoui Abdeslam Benlhachemi Abdeljalil Ihlal Ahmed Bouabid Khalid 《Journal of Materials Science: Materials in Electronics》2022,33(19):15791-15801
Journal of Materials Science: Materials in Electronics - Nanostructured Cu2O films have been developed on various conductive substrates (FTO, ITO, and Mo) by a low-cost electrodeposition process... 相似文献
78.
Taime Abderazzak Saaidi Abderrahim Satori Khalid 《Multimedia Tools and Applications》2018,77(20):27143-27162
Multimedia Tools and Applications - This paper introduces a new mesh segmentation approach into semantic parts, most closely resemble those made by humans, which is based on the pixel color of the... 相似文献
79.
Bennadji Abderrahim Mohammed Ameri Djillali Bensaid Yahia Azaz Bendouma Doumi Yaroub Al-Douri Fethi Benzoudji 《Journal of Superconductivity and Novel Magnetism》2016,29(2):277-283
Using first-principles calculations, the structural, electronic, and magnetic properties of ferromagnetic half-metallic full-Heusler Co2FeSi, Co2MnSi and Co2 Fe 0.5Mn 0.5Si alloy via the full-potential linearized augmented plane-wave (FP-LAPW) method in the generalized gradient (GGA) and GGA + U approximations are compared with other experimental and theoretical results. The electronic band structures and density of states (DOS) of the compounds indicate they are half metallic because of the existence of the energy gap in the minority spin (DOS and band structure), which yields perfect spin polarization. The half metallicity of the obtained material may prove useful for applications in spin-polarizers and spin-injectors of magnetic nanodevices. The calculated total spin magnetic moments are almost exactly that expected from the Slater-Pauling rule. 相似文献
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