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81.
Guy Bayada Mohamed El Alaoui Talibi 《Journal of Mathematical Analysis and Applications》2007,327(1):585-610
The purpose of this paper is to study a mathematical model of hydrodynamic lubrication when cavitation takes place. The obtained equation is a non-linear degenerate partial differential equation. 相似文献
82.
Belmesnaoui Aqzzouz Redouane Nouira Larbi Zraoula 《Journal of Mathematical Analysis and Applications》2006,324(1):49-59
We give several characterizations of Banach lattices on which each positive Dunford-Pettis operator is compact. As consequences, we obtain new sufficient and necessary conditions under which a norm of a Banach lattice is order continuous, a positive weakly compact operator is compact and the dual operator of a positive Dunford-Pettis operator is Dunford-Pettis. 相似文献
83.
Chemical composition and antioxidant activity of the essential oil of Juniperus phoenicea L. berries
Medini H Elaissi A Larbi Khouja M Piras A Porcedda S Falconieri D Marongiu B Chemli R 《Natural product research》2011,25(18):1695-1706
This study is designed to examine the chemical composition and antioxidant activity of the essential oil of Juniperus phoenicea L. ripe and unripe berries. GC and GC/MS analyses resulted in the detection of 42 components representing approximately 96.50-99.57% of the oils. Major components of the oils were α-pinene (58.61-77.39%), camphene (0.67-9.31%), δ-3-carene (0-10.01%) and trans-verbenol (0-5.24%). Antioxidant activities were determined by two different test systems, DPPH and ABTS radical scavenging activities. In both systems ripe berries exhibited better activity potential than the unripe ones. 相似文献
84.
Cupressus atlantica Gaussen, an endemic species from Morocco, is used in traditional medicine. The chemical composition of the essential oil isolated by hydrodistillation from the leaves was investigated by capillary gas chromatography and gas chromatography/mass spectrometry, and also evaluated for in vitro antimicrobial activity. Sixty-one components, representing 98.1% of the total, were detected of which fifty-seven were identified. Germacrene D (34.8%), alpha-pinene (13.6%), delta-cadinene (6.1%), alpha-phellandrene (5.5%), gamma-cadinene (5.0%), beta-caryophyllene (4.8%) and alpha-humulene (4.4%) were the predominant compounds. The oil was characterized by a relatively high amount of oxygenated monoterpenes (66.5%). The oil, screened for antimicrobial activity against both Gram-positive and Gram-negative, showed pronounced activity against all the microbes tested, except Pseudomonas, which showed resistance. 相似文献
85.
F. Alaoui E. Montero J.P. BazileM.J.P. Comuñas G. GallieroC. Boned 《Fluid Phase Equilibria》2011,301(2):131-136
This work reports new density data (178 points) of 1-butanol at twelve temperatures between 293.15 and 403.15 K (every 10 K), and fifteen pressures from 0.1 up to 140 MPa (every 10 MPa). An Anton Paar vibrating tube densimeter, calibrated with an uncertainty of ±0.5 kg m−3 was used to perform these measurements. The experimental density data were fitted with the Tait-like equation with low standard deviations. In addition, the isobaric thermal expansivity and the isothermal compressibility have been derived from the Tait-like equation. 相似文献
86.
Benstâali W. Larbi Daho Bachir N. Bendella S. Belasri A. Harrache Z. Caillier B. 《Plasma Chemistry and Plasma Processing》2020,40(6):1585-1603
Plasma Chemistry and Plasma Processing - This work presents an electric and kinetic study of homogeneous dielectric barrier discharge (DBD) in pure krypton (Kr). The electrical characterization and... 相似文献
87.
88.
Abdallah Larbi Doukara 《Tetrahedron》2010,66(10):1852-1858
A new route to S-alkylcarbamothioates is disclosed. In a first step, N-(2-aminophenyl)-4-methyl-thiazolin-2-thione is transformed into a mono- or disubstituted urea at nitrogen, and then in a second step, alkylated at sulfur. The resulting salts, after treatment with a base, gave S-alkylcarbamothioates in high isolated yields together with 3-methyl[1,3]thiazolo[3,2-a]benzimidazole under very mild conditions. 相似文献
89.
The vorticity equation and the mass continuity equation are used as constraints to aid in calculation of the vertical component of a wind field from horizontal wind components. Typically the horizontal wind components result from estimations obtained from radar data. Using a Hilbert space minimization formulation, we characterize the estimated vertical velocity as a solution of an elliptic boundary value problem whose coefficients are functions of the horizontal wind components. Differentiable dependence of the vertical component of the wind field with respect to the horizontal fields is established. Finite dimensional approximating problems are obtained. A numerical study is presented using a sample problem based on the Beltrami flow to compare accuracy of the estimated vertical wind component with the exact. Also, sensitivity to perturbations in horizontal wind components are observed. 相似文献
90.
Larbi Filali Yamina Brahmi Jamal Dine Sib Fatiha Kail Yahya Bouizem Djamel Benlakehal Kacem Zellama Ahmed Bouhekka Aissa Kebab Larbi Chahed 《Surface and interface analysis : SIA》2019,51(5):531-540
Highly crystallized hydrogenated silicon layers were obtained via the treatment of hydrogenated polymorphous silicon films in a molecular hydrogen ambient. This contrasts other postdeposition studies that obtained nanocrystalline silicon films but necessitated either a plasma activation or high-temperature annealing. The structure of the samples was analyzed by Raman spectroscopy to determine the crystallite volume fraction, which was found to increase up to 80% within 1 hour of treatment. Atomic force microscopy (AFM) showed that the roughness of the surfaces was found to increase after the H2 treatment. Optical transmission and spectroscopic ellipsometry revealed the pronounced porosity of the films characterized by a static refractive index that is below three, which is a low value for hydrogenated silicon films and a void fraction that is around 15% in the bulk of the films. The effect of the hydrogen molecules on the structure of the films was discussed in terms of the compressive stress exerted by the molecules, trapped in structural inhomogeneities, on the amorphous tissue. It is suggested that for this process to take effect, the films need to be porous and that the amorphous network needs to be in a “relaxed” state. 相似文献