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Oran, Algeria

University of Oran , or Es Sénia University , is a university located in western Algeria in the wilaya of Oran. It was established in November 1961 as part of the University of Algiers. On April 13, 1965 was made a separate campus, and on December 20, 1967 it became an independent University. It was the first university established after the independence of Algeria.Oran University is one of the most important and largest universities in Algeria. It annually graduates thousands of students in all disciplines from all over Algeria and other Arab and foreign countries. The university also provides scientific and pedagogical supervision to many other universities and university centers in western Algeria. Wikipedia.

Bourbie D.,Oran University of Science and Technology - Mohamed Boudiaf
Applied Physics Letters | Year: 2011

Recently the change in temperature dependence of conductivity observed in polythiophene field-effect transistors has been attributed to field-induced metal-insulator transition. Under a high source-drain voltage, the conductivity becomes independent from temperature and depends exponentially on the inverse of the square root of electric field. In this paper we present a theoretical interpretation of this behavior in the framework of hopping mechanism. The ingredient of this model, is the energy gained from the electrical field is always larger than the energy difference between the localized states involved into the charge transitions, which induces a crossover from phonon-assisted hopping to field-assisted hopping. © 2011 American Institute of Physics. Source

Dellil A.Z.,Oran University of Science and Technology - Mohamed Boudiaf
Mechanika | Year: 2014

This work presents a study of the thermal characteristics of a turbulent flow of a forced convection along various geometrical configurations: Smooth wall, wall corrugated in spiral, corrugated wall. The effects of pitch/diameter ratio and rib height to diameter ratio made it possible to develop this impact of this geometrical form (sometimes corrugated, sometimes spiral) in the intensification of the heat transfer. The physical process of increase in the heat transfer comes owing to the fact that the spiral shape of the tube contributes to break the formed boundary layer and to allow the continual replacement of the fluid meadows of the solid wall. The numerical results obtained prove that this corrugated form or into spiral intensifies the heat transfer thanks to model SST for Reynolds numbers varying from 5000 to 55000, Indeed when the pitch and the depth of the rib increases from P/dh = 0.18, e/dh = 0.02 to P/dh = 0.27, e/dh = 0.06. The ratio of the numbers of Nusselt increases with the rise in the step and the depth of the notch. Several explanations can be advanced, among these last, the spirals are the cause of the presence of the viscous effects, which slow down the flow in the notch of the spiral (broken boundary layer). The low depth of the notch, going from 0.02 up to 0.04 does not allow a significant thermal intensification, on the other hand for the strong values of the notch (0.05 to 0.06) the presence of turbulence supports good Nusselt. We notes that this last increases with the amplitude of the undulation up to the value of 0.05H. Beyond the value of the amplitude, the number of Nusselt tends towards the constant value. Source

Mortad M.H.,Oran University of Science and Technology - Mohamed Boudiaf
Complex Analysis and Operator Theory | Year: 2012

The aim of this paper is to give sufficient conditions on two normal operators (bounded or not), defined on a Hilbert space, which make their algebraic sum normal. The results are accompanied by some interesting examples and counter examples. © 2010 Springer Basel AG. Source

Mortad M.H.,Oran University of Science and Technology - Mohamed Boudiaf
Complex Analysis and Operator Theory | Year: 2012

We present in this paper a new version of the famous Fuglede-Putnam theorem where all the operators involved are unbounded. © 2011 Springer Basel AG. Source

Hakiki N.E.,Oran University of Science and Technology - Mohamed Boudiaf
Corrosion Science | Year: 2011

A comparative study including structural characterization and semiconducting properties of passive and thermally grown oxides on AISI 304 stainless steel is performed by near field microscopy, Auger electron spectroscopy, capacitance measurements and photoelectrochemistry. This comparative investigation is performed on thermally grown oxides at different temperatures and passive films formed at different potentials. The results obtained by characterization techniques show that the thickness of both oxides increases with increasing formation temperature and potential and allow discussing grain size and surface roughness vs. formation temperature. Capacitance measurements reveal semiconducting behavior of both iron and chromium oxides constituting whole passive and thermal oxides. These results allow extracting and discussing space charge layer thickness and doping densities of iron and chromium oxides in relation with formation conditions. The photocurrent results show a variation of the quantum efficiency with formation temperature and potential and a constant band gap value whatever the nature of the considered film. The variation of the quantum efficiency with applied potential in accordance with Pool-Frenkel model allow extracting and comparing donor densities with those obtained by capacitance measurements. © 2011 Elsevier Ltd. Source

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