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International Journal of Minerals,Metallurgy and Materials 2016年第11期23卷 1340-1345页

作者： Mohamed Benchikhi Rachida El Ouatib Sophie Guillemet-Fritsch Lahcen Er-Rakho Bernard Durand Laboratoire de Physico-Chimie des Matériaux Inorganiques Faculté des Sciences Ain Chock Université Hassan Ⅱ Casablanca Institut Carnot CIRIMAT CNRS Université de Toulouse

We report a simple method for preparing copper（II） molybdate（CuMoO_4） powders via a combustion-like process. A gel was first prepared by the polymerizable complex method, where citric acid was used as a complexing and polymerizing agent and nitric acid was used as an oxidizing agent. The thermal decomposition behavior of the（CuMo）-precursor gel was studied by thermogravimetry–differential thermal analysis（TG–DTA）, Fourier transform infrared spectroscopy（FTIR）, and X-ray diffraction（XRD）. We observed that the crystallization of CuMoO_4 powder was completed at 450°C. The obtained homogeneous powder was composed of grains with sizes in the range from 150 to 500 nm and exhibited a specific surface area of approximately 5 m^2/g. The average grain size increased with increasing annealing temperature. The as-prepared CuMoO_4 crystals showed a strong green photoluminescence emission at room temperature under excitation at 290 nm, which we mainly interpreted on the basis of the Jahn-Teller effect on [MoO_4^（2-）] complex anions. We also observed that the photoluminescence intensity increased with increasing crystallite size.

关键词： copper molybdate chemical synthesis photoluminescence Jahn-Teller effect

Potential generated by a massive inhomogeneous straight segment

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Research in Astronomy and Astrophysics 2011年第3期11卷 345-352页

作者： Nour-Eddine Najid El Haj Elourabi Mohamed Zegoumou Equipe Mécanique Statistique et Astronomie-Laboratoire de Physique Théorique et Appliquée Université Hassan Ⅱ ain chock-faculté des sciences ain chock BP 5366 Maarif Casablanca Morocco

The discoveries of binary asteroids have opened an important new field of research concerning the calculation of potential generated by irregular *** of them have an elongated shape.A simple model to describe the motion of a test particle in that kind of potential requires consideration of a finite homogeneous straight *** construct this model by adding an inhomogeneous distribution of mass. To be consistent with the geometrical shape of the asteroid,we explore a parabolic profile of the *** establish the closed analytical form of the potential generated by this inhomogeneous massive *** study of the dynamical behavior is fulfilled by the use of Lagrangian formulation,which allows us to calculate some two and three dimensional orbits.

关键词： asteroids—potential—inhomogeneous distribution

Some Estimates for the Fourier Transform on Rank 1 Symmetric Spaces

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Analysis in Theory and Applications 2018年第2期34卷 103-111页

作者： M.El Hamma R.Daher A.Akhlidj Laboratoire TAGMD Facultédes Sciences A¨?n Chock Université Hassan Ⅱ

Two estimates useful in applications are proved for the Fourier transform in the space L^2(X), where X a symmetric space, as applied to some classes of functions characterized by a generalized modulus of continuity.

关键词： Fourier transform generalized continuity modulus symmetric space

Theoretical prediction of structural,electronic and optical properties of quaternary alloy Zn_(1-x)Be_xS_ySe_(1-y)

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Chinese Physics B 2012年第3期21卷 321-327页

作者： Hacini K Meradji H Ghemid S El Haj Hassan F Laboratoire LPR D'epartement de PhysiqueFaculté des SciencesUniversité de Annaba Laboratoire de physique des Matériaux Faculté des SciencesUniversité Libanaise

Within density functional theory based on the full potentiM-linearized augmented plane wave method, we carry out the first-principles calculation of the structural, electronic, and optical properties of the zinc blende quaternary alloy Zn1-xBexSySe1-y. The Perdew-Burke-Ernzerhof generaized gradient approximation based on the optimization of total energy and the Engel-Vosko generalized gradient approximation based on the optimization of the corresponding potential are used. Our investigation on the effect of the composition on lattice constants, bulk modulus, band gap, optical dielectric constant, and refractive index shows a non-linear dependence. The energy gap Eg（x, y） has been determined over the entire compositions x and y. In addition, the energy band gap of the technologically important quaternary alloy Znl-xBexSySe1-y in conditions of being lattice matched to ZnS substrate has been investigated. It is noteworthy that the present work is the first theoretical study of the quaternary alloy of interest.

关键词： density functional theory full potential-linearized augmented plane wave method qua-ternary alloy lattice-matched substrate

OMT-G Modeling and Cloud Implementation of a Reference Database of Addressing in Morocco

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Journal of Geographic Information System 2013年第3期5卷 235-241页

作者： Mohamed El Imame Malaainine Hassane Rhinane Lahcen Baidder Hatim Lechgar faculté des sciences ain chock Université Hassan II-Casablanca Casablanca Maroc

A reference database of addressing is an important resource for urban applications. The efficiency of an addressing system depends on both data quality and technical architecture. Data must respect a standard model that is flexible to meet different cases in the field. The technical architecture should be service oriented to offer a shared resource for multiple users and applications. This paper is to develop an addressing model for Morocco that extends Davis’s and Fonseca’s model presented in their work on the certainty of locations produced by an address geocoding system. We discuss the addressing data dictionary and acquisition plan in Morocco, revealing a diversified data management environment, characterized by multiple sources and actors. As a novelty in the field of GIS, we establish our technical architecture around cloud computing, according Service Oriented Application (SOA) standards. Our approach is based on the three pillars of cloud computing which are Software as a Service (SaaS), Platform as a Service (PaaS) and Infrastructure as a service (IaaS).

关键词： Reference Database of Addressing Morocco GIS OMT-G Modeling Cloud Computing

Numerical Study of Greenhouse Nocturnal Heat Losses

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Journal of Thermal Science 2011年第4期20卷 377-384页

作者： F.Berroug E.K.Lakhal M.El Omari M.Faraji H.El Qarnia Laboratoire d'Automatique de l'Environnement et Procédés de Transfert UniversitéCadi AyyadFacultédes Sciences Semlalia-Département de PhysiqueMarrakech-MarocAffiliéau CNRSTURAC 28 Laboratoire de Physique des Materiaux MicroelectroniqueAutomatique et TechniqueDepartement de PhysiquesFaculte des Sciences Ain ChockUniversite Hassan IICasablanca-Maroc

In this study we quantify and analyze different components of nocturnal losses from a heated greenhouse with the presence of vegetation for typical winter weather conditions in Marrakesh-Morocco,using a non linear model,based on the greenhouse heat and mass *** was found that 12% of the total input heat was dissipate as a sensible and latent leakage losses,66% was lost by convective exchange through air-inner *** gain of energy at the inner-cover is dissipated at the outer-cover by radiation(66%)and convection(34%).This results point toward some practical measures to reduce heat losses:increasing air tightness,using covering materials with low-emissivity in the long wave band or putting up an external thermal curtain should provide significant energy savings.

关键词： Greenhouse energy balance heat losses numerical analysis.

Apatite Fission-Track Datings on Hercynian Granites from Rehamna and Jebilet Massifs(Western Meseta,Morocco):Paleogeographic Implications and Interpretation of AFT Age Discrepancies

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地学前缘 2009年第S1期16卷 217-218页

作者： Omar Saddiqi Fatima Zahra EL Haimer Hassan Ⅱ University CasablancaMoroccoFaculty of Sciences Laboratoire Géosciences Faculté des SciencesUniversite Hassan Ⅱ An Chock

This work is based on apatite fission-track analysis of samples(mostly granites)from the basement of the Cretaceous-Tertiary Phosphate and Ganntour Plateaus, exposed in the Jebilet and Rehamna massifs (Western Meseta,... 详细信息

关键词： thermochronology fission track apatite exhumation Rehamna Jebilet Western Meseta Morocco

Energy calibration of laterally segmented electromagnetic calorimeters based on neutral pion detection

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Nuclear Science and Techniques 2017年第11期28卷 164-171页

作者： Malek Mazouz faculté des sciences de Monastir 5000 Monastir Tunisia

This paper describes a method for energy calibration of laterally segmented electromagnetic calorimeters based on the detection of two-photon decays of π~0 *** calibration procedure performs a X^2 function minimization between the measured π~0 energy in the calorimeter and its expected energy deduced from the π~0 momentum direction. The performance of this technique is demonstrated with a Monte Carlo simulation of an experimental case where biased calibration coefficients are employed. The real calibration coefficients are restored with less than 1% relative accuracy when a sufficient number of π~0 is detected. This technique is applied to monitor daily the calibration coefficients of the calorimeter used in the Jefferson Lab Hall A DVCS experiments.

关键词： Electromagnetic calorimeters Energy calibration Detector modeling and simulations Data processing methods

Qualitative analysis and simulation of a nonlinear integro-differential system modeling tumor-immune cells competition

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International Journal of Biomathematics 2018年第8期11卷 171-190页

作者： Bouchra Aylaj Departement de Mathematiques et Informatique faculte des sciences ain chock Km 8 Route d'El adida B.P. 5366 Maarif 20100 Casablanca 20000 Maro

This paper deals with a qualitative and computational study of a class of integrodifferential model, with a nonlinear growth rate. The model is applied to immunology problems, in particular to the competition between tumors and immune system. Our purpose is to take into account the activity transfer processes bet ween cells. The first part of this paper deals with the modeling, while the second part develops the existence and uniqueness of global solutions to the initial boundary value problem related to the application of the model. Finally, numerical simulations are used to illustrate the results obtained for a dynamic of tumor cells contrasted by the immune system.

关键词： Population dynamics kinetic theory nonlinear semigroup separable equations immune competition quasilinear cauchy problem global solution integrodifferentialequations simulation

GIS and Networks: Business Anomalies and Topological Errors, Linear Elements Case

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Journal of Geographic Information System 2014年第2期6卷 115-122页

作者： Omar Bachir Alami Hatim Lechgar Mohamed El Imame Malaainine Fatima Bardellile Ecole Hassania des Travaux Publics Casablanca Maroc faculté des sciences ain chock Université Hassan II Casablanca Maroc

The quality control of geographic data, especially from a topological and semantic perspective, is a must for its good management and use. However, while updating spatial data, some sorts of anomalies are affecting it, due to negligence or non-respect of business and topological rules. Hence the necessity of a solution that enables detecting theses anomalies. Nowadays, Geographic Information Systems (GIS) have become essential for decision-making in any project that manages spatial data. GIS functionalities and tools give the possibility of defining the topology of vector data. Nevertheless, the topology alone does not respond to the needs in matter of defining specific rules for every facility network. This means, we could find topological errors in the spatial database, but taking into account business rules, they are correct and vice versa. The main objective of this article is firstly to define business rules for the linear elements of a network. Secondly to premeditate the algorithms that detect the violation of the defined rules in order to have a good quality control of geographic data.

关键词： GIS Networks Geodatabase Topology Business Rule