https://dspace.univ-ouargla.dz/jspui/handle/123456789/3983 2026-04-28T09:29:26Z https://dspace.univ-ouargla.dz/jspui/handle/123456789/6481 Titre: PESUDOPOTENIAL DENSITY FUNCTIONAL THEORY STUDY OF AU/YBCO INTERFACE Auteur(s): Abdelouahab OUAHAB Résumé: The Au/YBCO interface is represented by a simple model showing the contact of two surfaces of an epitaxial interface with the orientation relationship Au(111)/YBCO(001) where [011]Au is parallel to [100]YBCO for which termination surface of the substrate corresponds to the CuO layer of YBCO. A simplest model with different configuration Au(001)/YBCO(001) is used to calculate the interaction energies using pseudopotential DFT approach as a function of the separation distance between the metallic film and the surface of the superconductive substrate in different configurations. The configuration with the highest interaction energy at the interface Au/YBCO(001) was found to correspond to the deposition of Au film in such way that the Au atoms of the interfacial monolayer are top oxygen atoms of the substrate surface. Description: AST Annales des Sciences et Technologie 2007-01-01T00:00:00Z https://dspace.univ-ouargla.dz/jspui/handle/123456789/6472 Titre: VARIATION TEMPORELLE DE LA VALEUR NUTRITIVE DES PRINCIPALES PLANTES SPONTANEES BROUTEES PAR LE DROMADAIRE DANS LE SUD EST ALGERIEN Auteur(s): HOUARI Kahina Dalila; CHEHMA Abdelmajid Résumé: Based on the study we did concerning the temporal variation of the chemical composition and assessment of the energetic value corresponding to the spontaneous principles plants grazed by the dromedary in south ester of Algeria, we could get for the chemical composition estimation, that the whole plants are relatively variables in MS, going from 20.51% for Agga to 75.76% for Tagtag, poor in MAT could not overtake 4.81 %, whilst for CB, MM and MO; the result in possession are relatively variables. The seasonal variation of the chemical composition is not very clear it is weak.The seasonal average of MS show that a rich season is the winter, with 58.96%, in comparison with autumn and spring with respectively 52.45% and 53.41%. Concerning the seasonal average of MO, we got a bring contents with 89.28% for spring, 85.7% for winter and 82.42% for autumn. The same thing for MM, we got a contents of 17.58% for autumn, 14.31% for winter and finally 10.71% for spring. Concerning the seasonal average of MAT, we got the highst rates for spring season with 4.22%, followed by winter season with 3.89% and 3.48% for autumn. The seasonal variation of CB average show that spring is the richest season with 27.10%, but for autumn and spring we got a bring contents with respectivelly 23.71% and 24.71%. Concerning the energetic value, in general, the highest values of UFL and UFV are got for Zeita, Alenda and Agga with respectivelly 0.80, 0.78 and 0.75 UFL/Kg of MS and 0.77, 0.73 and 0.73 UFV/Kg of MS. On the other hand, the weakest are those got for Tagtag and Arfege with 0.58 et 0.54 UFL/Kg of MS and 0.46 UFV/Kg of MS. Concerning the seasonal variation, highest values of UFL and UFV are those got in spring with 0.72 UFL/Kg of MS and 0.65 UFV/Kg of MS in comparison with 0.65 and 0.63 UFL/Kg of MS and 0.59 to 0.56 UFV/Kg of MS respectively got in autumn winter. Description: AST Annales des Sciences et Technologie 2007-01-01T00:00:00Z https://dspace.univ-ouargla.dz/jspui/handle/123456789/6474 Titre: CONTRIBUTION A L’ETUDE DE L’EFFET AERODYNAMIQUE ET MICROCLIMATIQUE DE BRISE VENT DANS LA REGION DE OUARGLA Auteur(s): MEDJEBER TEGUIG T Résumé: Au sahara , le vent est l’ennemi insidieux dont on a tendance à minimiser l’importance , son action est d’autant plus marqué et redoutable que le climat est plus aride. Dans la région de Ouargla les manifestations de l’action de vent et de sable sur les terres agricoles sont multiples , la lutte contre le vent et le sable par le biais de brise vent inerte ou vivant est une nécéssité pour la réussite de tout projet d’aménagement ou de protection des oasis. Description: AST Annales des Sciences et Technologie 2007-01-01T00:00:00Z https://dspace.univ-ouargla.dz/jspui/handle/123456789/6470 Titre: UN PROBLEME DE COQUES ELASTIQUES MINCES AVEC PROBLEME LIMITE A ENERGIE NON BORNEE Auteur(s): D. A. CHACHA; I. MERABET Résumé: We study in this work a singular perturbation problem depending on a small parameter ! 0 , which characterizes the balance of a linearly elastic thin shell of thickness 2 and elliptic middle surface, within the framework of the theory of Koiter. For ! 0 this problem is well posed in the space of admissible displacements. On the other hand if " 0 the limit problem is ill-posed for a choice of singular loadings, i.e., which are not in the dual of the space of the limit problem. Thus the deformation energy of the shell tends towards the infinite one and it concentrates in internal layers. Then we determine the structure of these internal layers and we justifie the convergence. Description: AST Annales des Sciences et Technologie 2007-01-01T00:00:00Z