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Bhihi M.,Mohammed V University | Lakhal M.,Mohammed V University | Labrim H.,National Center for Energy | Benyoussef A.,Mohammed V University | And 5 more authors.
Chinese Physics B | Year: 2012

In this work, the hydrogen storage properties of the Mg-based hydrides, i.e., Mg 1-x M x H 2 (M = Ti, V, Fe, 0 ≤ x ≤ 0.1), are studied using the Korringa - Kohn - Rostoker (KKR) calculation with the coherent potential approximation (CPA). In particular, the nature and concentrations of the alloying elements and their effects are studied. Moreover, the material's stability and hydrogen storage thermodynamic properties are discussed. In particular, we find that the stability and the temperature of desorption decrease without significantly affecting the storage capacities. © 2012 Chinese Physical Society and IOP Publishing Ltd. Source

Gourai K.,Hassan II University | Allam K.,Hassan II University | El Bouari A.,Hassan II University | Belhorma B.,National Center for Energy | And 2 more authors.
Journal of Materials and Environmental Science | Year: 2015

AquaSolar-Maroc project focuses on brackish water desalination using solar energy. This project is funded by the Institute for Research in Solar Energy and New Energies (IRESEN), and involves both scientists and engineers from CNESTEN, Moulay Ismail and Hassan II Universities, and the "LSA-Industries" and "Tube et Profil" companies, and the Plataforma Solar de Almeria (PSA-Spain).The chosen technologies consist of a combination of reverse osmosis (RO) powered by photovoltaic (PV) panels and membrane distillation (MD) powered by solar thermal panels. This station therefore uses both the heat and the light emitted by the sun to produce on average 5m3 of drinking water per hour. The solar potential of Morocco is among the most higher in the world, with a peak of the global normal irradiance up to 1100W/m2 and an average of 2.8MWh/year. The solar field of the station is composed of 57 flat photovoltaic solar panels and 18 flat thermal solar panels, producing respectively 10kWe and 14kWth necessary to supply autonomously the whole station composed of the RO and MD processes as well as the accessories (air conditioning and lighting). Among the project work packages, we can cite: • Study of hydrological and climatic conditions of the site • Study of the technical performances of RO/PV and MD/thermal processes individually as well as their coupling • Study of perspective material for low cost water treatment This article gives an overview on the AquaSolar-Maroc project, and the main results on the hydrological and climatic conditions of the site. Source

Lakhal M.,Mohammed V University | Bhihi M.,Mohammed V University | Labrim H.,National Center for Energy | Benyoussef A.,Mohammed V University | And 10 more authors.
International Journal of Hydrogen Energy | Year: 2013

In this work, we propose a model to investigate the hydrogen storage ab/desorption kinetic properties for the pure MgH2 using Kinetic Monte Carlo (KMC) simulations. To do such computations, the activation energies for different elementary processes have been estimated. Moreover, the different thermodynamical quantities of interest are determined by performing the ab-initio calculations. Then, we discuss the hydrogen diffusion in magnesium hydride (such as adsorption, diffusion and desorption). More precisely, we study the effect of each elementary mechanism on the diffusion that we characterize through the density distribution of hydrogen atoms including filling ratios, diffusion time, temperature and pressure. Among others, we show that all elementary mechanisms are needed to reproduce a behavior of ab/desorption which correlates well with the experimental results reported in literature. In particular, at high temperature and pressure, the results of simulations indicate that the studied material involves slow kinetics. © Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source

Boujnah M.,Mohammed V University | Zaari H.,Mohammed V University | Labrim H.,National Center for Energy | Benyoussef A.,Mohammed V University | And 3 more authors.
Journal of Applied Physics | Year: 2014

The electronic structure, magnetic, and optical properties in cubic crystalline phase of Zr1-xTMxO2 (TM=V, Mn, Fe, and Co) at x=6.25% are studied using density functional theory with the Generalized Gradient Approximation and the modified Becke-Johnson of the exchange-correlation energy and potential. In our calculations, the zirconia is a p-type semiconductor and has a large band gap. We evaluated the possibility of long-range magnetic order for transition metal ions substituting Zr. Our results show that ferromagnetism is the ground state in V, Mn, and Fe-doped ZrO2 and have a high value of energy in Mn-doped ZrO2. However, in Co-doped ZrO2, antiferromagnetic ordering is more stable than the ferromagnetic one. The exchange interaction mechanism has been discussed to explain the responsible of this stability. Moreover, it has been found that the V, Mn, and Fe transition metals provide half-metallic properties considered to be the leading cause, responsible for ferromagnetism. Furthermore, the optical absorption spectra in the TM -doped cubic ZrO2 are investigated. © 2014 AIP Publishing LLC. Source

Mounkachi O.,Institute for Nanomaterials and Nanotechnology | Salmani E.,Mohammed V University | Boujnah M.,Mohammed V University | Labrim H.,National Center for Energy | And 8 more authors.
Bulletin of Materials Science | Year: 2014

Structural and magnetic properties of Sn0.95Co 0.05O2 nanocrystalline and diluted magnetic semiconductors have been investigated. This sample has been synthesized by co-precipitation route. Study of magnetization hysteresis loop measurements infer that the sample of Sn0.95Co0.05O2 nanoparticle shows a well-defined hysteresis loop at 300 K temperature, which reflects its ferromagnetic behaviour. We confirmed the roomtemperature intrinsic ferromagnetic (FM) semiconductors by ab initio calculation, using the theory of the functional of density (DFT) by employing the method of Korringa-Kohn- Rostoker (KKR) as well as coherent potential approximation (CPA, explain the disorder effect) to systems. The ferromagnetic state energy was calculated and compared with the local-moment-disordered (LMD) state energy for local density approximation (LDA) and LDA-SIC approximation. Mechanism of hybridization and interaction between magnetic ions in Sn0.95Co0.05O 2 is also investigated. To explain the origin of ferromagnetic behaviour, we give information about total and atoms projected density of state functions. © Indian Academy of Sciences. Source

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