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Rabat, Morocco

Korytov M.,French National Center for Scientific Research | Budagosky J.A.,University of Valencia | Brault J.,French National Center for Scientific Research | Huault T.,French National Center for Scientific Research | And 5 more authors.
Journal of Applied Physics | Year: 2012

The capping of GaN quantum dots (QDs) with an Al 0.5Ga 0.5N layer is studied using transmission electron microscopy and atomic force microscopy in combination with theoretical calculations. The capping process can be divided into several well-distinguishable stages including a QD shape change and a local change of the Al 0.5Ga 0.5N capping layer composition. The phase separation phenomenon is investigated in relation with the capping layer thickness. Amount of the chemical composition fluctuations is determined from separate analysis of scanning transmission electron microscopy and high-resolution transmission electron microscopy images. The local distortion of atomic lattice in the QD surroundings is measured by high-resolution electron microscopy and is confronted with theoretically calculated strain distributions. Based on these data, a possible mechanism of alloy demixing in the Al 0.5Ga 0.5N layer is discussed. © 2012 American Institute of Physics. Source

Benaissa M.,CNRST | Korytov M.,French National Center for Scientific Research | Van Aken P.A.,Max Planck Institute for Intelligent Systems (Stuttgart) | Vennegues P.,French National Center for Scientific Research
MATEC Web of Conferences | Year: 2013

To shed light on these confined properties, a technique with a high energy-and-spatial resolution is of absolute need. Modern transmission electron microscopy (TEM) is the most suitable technique for a direct measurement of optical and structural properties at a nanometer scale. Thanks to the successful construction of aberration corrected transmission electron microscopes, the mapping of atomic positions with high accuracy becomes a routine experiment enabling therefore a more intuitive interpretation of structural deformation (strain). In addition, the recent development in energy-filters, especially when coupled to monochromated electron-beams, measurements of physical properties are achieved with unprecedented performances. The case of individual buried GaN/(AlGaN) quantum dots is discussed. © Owned by the authors, published by EDP Sciences, 2013. Source

d'Acremont E.,CNRS Paris Institute of Earth Sciences | Gutscher M.-A.,French National Center for Scientific Research | Rabaute A.,CNRS Paris Institute of Earth Sciences | Mercier de Lepinay B.,University of Nice Sophia Antipolis | And 14 more authors.
Tectonophysics | Year: 2014

Two recent destructive earthquakes in 1994 and 2004 near Al Hoceima highlight that the northern Moroccan margin is one of the most seismically active regions of the Western Mediterranean area. Despite onshore geodetic, seismological and tectonic field studies, the onshore-offshore location and extent of the main active faults remain poorly constrained. Offshore Al Hoceima, high-resolution seismic reflection and swath-bathymetry have been recently acquired during the Marlboro-2 cruise. These data at shallow water depth, close to the coast, allow us to describe the location, continuity and geometry of three active faults bounding the offshore Nekor basin. The well-expressed normal-left-lateral onshore Trougout fault can be followed offshore during several kilometers with a N171°E ± 3° trend. Westward, the Bousekkour-Aghbal normal-left-lateral onshore fault is expressed offshore with a N020°E ± 4° trending fault. The N030°E ± 2° Bokkoya fault corresponds to the western boundary of the Plio-Quaternary offshore Nekor basin in the Al Hoceima bay and seems to define an en échelon tectonic pattern with the Bousekkour-Aghbal fault. We propose that these three faults are part of the complex transtensional system between the Nekor fault and the Al-Idrissi fault zone. Our characterization of the offshore expression of active faulting in the Al Hoceima region is consistent with the geometry and nature of the active fault planes deduced from onshore geomorphological and morphotectonic analyses, as well as seismological, geodetic and geodynamic data. © 2014 Elsevier B.V. Source

Bensalah M.O.,Mohammed V University | Chakchak H.,CNRST | Ghazali A.,Mohammed V University | Sadoune Z.,Mohammed V University
International Review of Mechanical Engineering | Year: 2011

In this work, we study the shape memory alloys (SMA) micromechanical behaviour in the perfect transformation plasticity. This study is based on the kinematical description of the physical mechanisms at the origin of the phenomenon, and on the thermodynamical analysis of the irreversible processes presented by these alloys in such a transformation. The pseudoelastical behaviour of SMA is described by defining a pseudoelastical potential through the Gibbs theory, and by application of the second principle of the thermodynamic. This approach allowed us to incorporate the change of the martensite variants shape in such thermomechanical behaviour and to analyse the hysteretic behaviour of these materials. © 2011 Praise Worthy Prize S.r.l. - All rights reserved. Source

Dagdougui H.,University of Genoa | Ouammi A.,CNRST | Sacile R.,University of Genoa
Proceedings - 2012 7th International Conference on System of Systems Engineering, SoSE 2012 | Year: 2012

Grid integration of wind power plants is becoming the main growing form of electricity generation among renewable energies. Recently, more interest is given to microgrids due to its potential benefits. The optimal operation of interconnected microgrids aims the matching of energy production with a dynamic load. In this paper, a control strategy for the wind power exchanges in a network of microgrids is formalized and tested on a Moroccan case study. The control variables are the instantaneous flows of wind power in the network of microgrids. The state is represented by the energy stored in each microgrid. This paper aims to minimize the variations of the energy stored in each storage device from a reference value, as well as to minimize the exchange of power between the microgrids. © 2012 IEEE. Source

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