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53.
Aziz K. Jahja Mardiyanto Panitra Wagiyo Honggowiranto Salim Mustofa Yunasfi Yunasfi 《Ionics》2016,22(2):219-227
Spinel LiMn2O4 has been known to be a technologically important, environmental-friendly, and low-cost cathode material used in Li-based rechargeable batteries, and it is also widely available. Nanoparticle spinel LiMn2O4 has been synthesized by the top-down, high-energy milling, and hydrothermal methods. SEM images, X-ray diffraction patterns, and neutron high-resolution powder diffraction patterns have confirmed the nanocrystalline nature of the spinel LiMn2O4 samples. Raman and Fourier transform infrared (FTIR) measurements show typical absorption and vibration spectra typical for the spinel LiMn2O4 showing the formation of various metallic bonds in the sample. The strongest Raman and FTIR signals come from the higher frequency region, with weaker signals appearing in the lower frequency range. 相似文献
54.
Sebastián Domínguez Gabriel N. Gatica Antonio Márquez Salim Meddahi 《Advances in Computational Mathematics》2016,42(3):675-720
In this work we analyze a primal-mixed finite element method for the coupling of quasi-Newtonian fluids with porous media in 2D and 3D. The flows are governed by a class of nonlinear Stokes and linear Darcy equations, respectively, and the transmission conditions on the interface between the fluid and the porous medium are given by mass conservation, balance of normal forces and the Beavers-Joseph-Saffman law. We apply a primal formulation in the Stokes domain and a mixed formulation in the Darcy formulation. The “strong coupling” concept means that the conservation of mass across the interface is introduced as an essential condition in the space where the velocity unknowns live. In this way, under some assumptions on the nonlinear kinematic viscosity, a generalization of the Babu?ka-Brezzi theory is utilized to show the well posedness of the primal-mixed formulation. Then, we introduce a Galerkin scheme in which the discrete conservation of mass is imposed approximately through an orthogonal projector. The unique solvability of this discrete system and its Strang-type error estimate follow from the generalized Babu?ka-Brezzi theory as well. In particular, the feasible finite element subspaces include Bernadi-Raugel elements for the Stokes flow, and either the Raviart-Thomas elements of lowest order or the Brezzi-Douglas-Marini elements of first order for the Darcy flow, which yield nonconforming and conforming Galerkin schemes, respectively. In turn, piecewise constant functions are employed to approximate in both cases the global pressure field in the Stokes and Darcy domain. Finally, several numerical results illustrating the good performance of both discrete methods and confirming the theoretical rates of convergence, are provided. 相似文献
55.
Tijani A. Apalara Salim A. Messaoudi Ahmed A. Keddi 《Mathematical Methods in the Applied Sciences》2016,39(10):2671-2684
In this work, we study the well‐posedness and the asymptotic stability of a one‐dimensional linear thermoelastic Timoshenko system, where the heat conduction is given by Cattaneo's law and the coupling is via the displacement equation. We prove that the system is exponentially stable provided that the stability number χτ=0. Otherwise, we show that the system lacks exponential stability. Furthermore, in the latter case, we show that the solution decays polynomially. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
56.
In this paper, we introduce one-parameter homothetic motions in the generalized complex number plane (\({\mathfrak{p}}\)-complex plane)wheresuch that \({-\infty < \mathfrak{p} < \infty}\). The velocities, accelerations and pole points of the motion are analysed. Moreover, three generalized complex number planes, of which two are moving and the other one is fixed, are considered and a canonical relative system for one-parameter planar homothetic motion in \({\mathbb{C}_{J}}\) is defined. Euler-Savary formula, which gives the relationship between the curvatures of trajectory curves, during the one-parameter homothetic motions, is obtained with the aim of this canonical relative system.
相似文献
$$\mathbb{C}_{J}=\left\{x+Jy:\,\,\, x,y \in \mathbb{R},\quad J^2=\mathfrak{p},\quad \mathfrak{p} \in \{-1,0,1\} \right\} \subset \mathbb{C}_\mathfrak{p}$$
$$\mathbb{C}_\mathfrak{p}=\{x+Jy:\,\,\, x,y \in \mathbb{R}, \quad J^2=\mathfrak{p}\}$$
57.
This Technical Note presents the direct surface modification of a glass/PTFE hybrid microfluidic chip, via radio frequency glow discharge plasma polymerisation of tetraethlylene glycol dimethylether (tetraglyme), to produce hydrophilic, non-fouling, PEO-like surfaces. We use several techniques including X-ray photoelectron spectroscopy (XPS), direct enzyme-linked immunosorbent assays (ELISA) and immunofluorescent imaging to investigate the channel coatings. Our results indicate the successful deposition of a PEO-like coating onto microchannel surfaces that has both solution and shelf stability (>3 months) and is capable of preventing fibrinogen adsorption to the microchannel surfaces. 相似文献
58.
Salim A. Messaoudi Nasser‐eddine Tatar 《Mathematical Methods in the Applied Sciences》2007,30(6):665-680
In this paper the nonlinear viscoelastic wave equation in canonical form with Dirichlet boundary condition is considered. By introducing a new functional and using the potential well method, we show that the damping induced by the viscoelastic term is enough to ensure global existence and uniform decay of solutions provided that the initial data are in some stable set. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
59.
The aim of this paper is to get a good approximation of damping properties of viscoelastic damped sandwich structures. Firstly we will compare the classical models based on the kinematics of Kirchhoff-Love, Mindlin, Reddy or Touratier. In the second stage these models are used to establish the zig-zag models which describe a piecewise continuous displacement field. These models are compared in the static and the dynamic fields. In all cases the Finite-Element-based solution is considered as reference. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
60.
Rawhi H. Al‐Far Salim F. Haddad Basem Fares Ali 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(8):m321-m324
In the structural motifs of two isomorphous triclinic salts, (C5H6Br2N3)2[MBr4] (M = CdII and MnII), each [MBr4]2− anion interacts with eight surrounding 2,6‐diamino‐3,5‐dibromopyridinium cations through intermolecular C/N—H...Br and Br...Br interactions, leading to a three‐dimensional framework structure. The cations show a minor degree of π–π stacking, adding extra stability to the three‐dimensional architecture. 相似文献