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121.
Microstructure, electrical conductivity, and rheological properties of nanocomposites based on isotactic polypropylene (iPP) containing semiconductor nanoparticles of TiO2 were studied. Compatibilized and uncompatibilized nanocomposites containing a wide range of TiO2 concentrations (up to 15 vol%) were prepared by melt compounding in a twin-screw extruder via a masterbatch method. An anhydride-modified PP (AMPP) was used as the compatibilizer. Atomic force microscopy (AFM), scanning electron microscopy (SEM), and image analysis techniques were utilized to study the morphology evolution in the samples. Analyzing the results of direct current (DC) electrical conductivity measurements showed a lower percolation threshold for the uncompatibilized samples, compared to the compatibilized ones. In order to estimate the percolation threshold, linear and nonlinear melt-state viscoelastic properties of the samples were studied. Liquid-solid transition and nonterminal behavior of the uncompatibilized samples were observed at relatively lower range of TiO2 loading, compared to the compatibilized samples. It was an indication of lower rheological percolation threshold in the uncompatibilized nanocomposites which was in agreement with the electrical percolation threshold. Scaling analysis of strain sweep tests above the percolation thresholds of the nanocomposites resulted in a lower fractal dimension for the uncompatibilized samples. 相似文献
122.
The general mixed quasi variational inequality containing a nonlinear term φ is a useful and an important generalization of variational inequalities. The projection method can not be applied to solve this problem due to the presence of nonlinear term. It is well known that the variational inequalities involving the nonlinear term φ are equivalent to the fixed point problems and resolvent equations. In this article, the authors use these alternative equivalent formulations to suggest and analyze a new self-adaptive iterative method for solving general mixed quasi variational inequalities. Global convergence of the new method is proved. An example is given to illustrate the efficiency of the proposed method. 相似文献
123.
Abdellah El Kinani Mohamed Amine Nejjari Mohamed Oudadess 《Mediterranean Journal of Mathematics》2005,2(2):205-213
Using the notion of a normal cone, we give results of Vidav-Palmer type in terms of hermitian, quasi-hermitian and uniformly quasi-hermitian elements. Consequences are also given. 相似文献
124.
Farhad Sadeghi Abdellah Ajji Pierre J. Carreau 《Journal of Polymer Science.Polymer Physics》2008,46(2):148-157
A blend of two polypropylene resins, different in molecular structure, one with linear chains and the other with long chain branches, was investigated to develop microporous membranes through melt extrusion (cast film process) followed by film stretching. The branched component significantly affected the row‐nucleated lamellar crystalline structure in the precursor films. The arrangement and orientation of the crystalline and amorphous phases were examined by wide angle X‐ray diffraction and Fourier transform infrared spectroscopy methods. It was found that blending of a small amount of a long chain branched polypropylene improved the orientation of the both crystalline and amorphous phases in the precursor films. Annealing, followed by cold and hot stretching were consequently employed to generate and enlarge pores in the films as a result of lamellae separation. SEM micrographs of the surface of the membranes obtained from the blend revealed elongated thin fibrils and a large number of lamellae. The lamellae thickness for the blend was much shorter in comparison to that of the linear PP precursor film. The permeability of the samples to water vapor and N2 was significantly enhanced (more than twice) for the blend system. The porosity of the blend membrane showed a significant improvement with a value of 53% compared to 41% for the linear PP membrane. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 148–157, 2008 相似文献
125.
Abdellah Elkinani 《Rendiconti del Circolo Matematico di Palermo》1993,42(2):257-272
We introduce the use of a harmonic functional calculus in the generalized discussion of theorems of von-Neumann, ky Fan; and their extended versions. 相似文献
126.
127.
Abdellah El Kinani 《Rendiconti del Circolo Matematico di Palermo》2008,57(3):343-352
We obtain weighted algebra analogues of the classical theorems of N. Weiner and P. Lévy on absolutely convergent Fourier series
相似文献
128.
Abdellah Bnouhachem Min Li Sheng Zhaohan 《Journal of Computational and Applied Mathematics》2010,234(12):3356-3365
In this paper, we suggest and analyze an inexact implicit method with a variable parameter for mixed variational inequalities by using a new inexactness restriction. Under certain conditions, the global convergence of the proposed method is proved. Some preliminary computational results are given to illustrate the efficiency of the new inexactness restriction. The results proved in this paper may be viewed as improvement and refinement of the previously known results. 相似文献
129.
Mohamed Benkhali Jaouad Kharbach Idriss El Fakkousy Walid Chatar Abdellah Rezzouk Mohammed Ouazzani-Jamil 《Physics letters. A》2018,382(36):2515-2525
Integrability in the Painlevé sense of the trapped ionic system in the quadrupole field with superpositions of rotationally symmetric hexapole and octopole fields is studied. Five integrable cases of the system are reported. First Integrals of the planar motion are founded. Confirming three-dimensional integrability of the equations of motion, the third explicit integrals of motion are constructed directly for each case. We carried out a numerical study to observe the regularity and chaotic regions via the Poincaré surface of sections, and corroborate the analytical results. 相似文献
130.
Let M be a compact Riemannian manifold, E a Riemannian vector bundle on M and the unit subbundle of E. We prove that there is no radial graph on with a strictly positive Gaussian curvature and that the Gaussian curvature of a convex radial graph must be identically equal to zero. Moreover, by solving on a nonlinear degenerate equation of Monge-Ampère type, we prove the existence of radial graphs having simultaneously a Gaussian curvature identically equal to zero and a prescribed strictly positive vertical Gaussian curvature.Mathematics Subject Classification (2000):35J60, 53C55, 58G30 相似文献