ED Sciences Chimiques
Study of Ga2O3-Gd2O3-Nb2O5 phase diagram: toward new niobate based transparent ceramics in the mid-infrared optical window
by Louis CORNET (ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux)
The defense will take place at 14h00 - Amphithéatre ICMCB – UMR5026 87, Avenue du Docteur Schweitzer 33608 PESSAC cedex (France)
in front of the jury composed of
- Véronique JUBERA - Professeure des universités - ICMCB - Université de Bordeaux - Directeur de these
- Bruno VIANA - Directeur de recherche - Institu de Recherche de Chimie-ParisTech (IRCP) - Rapporteur
- Nicolas DACHEUX - Professeur des universités - ICSM/LIME - Université de Montpellier - Rapporteur
- Nadine MILLOT - Professeur des universités - ICB - Université de Bourgogne - Examinateur
- Odile MERDRIGNAC-CONANEC - Maîtresse de conférences - ISCR - Université de Rennes 1 - Examinateur
- Cyril AYMONIER - Directeur de recherche - ICMCB - Examinateur
- Rémy BOULESTEIX - Maître de conférences - IRCer - Université de Limoges - Examinateur
- Jean-Marc HEINTZ - Professeur des universités - ICMCB - Bordeaux INP - CoDirecteur de these
The development of 1.7-2.7 µm highly energetic compact LASER sources represent an important challenge regarding the societal and technological needs of opto-electronic devices. In fact, their fabrication and improvement can significantly impact many applications; covering of the eye spectral region, healthcare, defense sector, optical communication. Since 1995, the first transparent polycrystalline ceramics with LASER radiation have paved the way for the development of this new class of materials as gain sources. In addition to the many advantages inherent in their manufacturing process, they also expand the catalogue of compounds available for these applications. However, only a few active crystallized materials (AG:Ho3+, LuAG:Ho3+, Lu2O3:Ho3+ and Y3NbO7:Ho3+) have been developed and their performance as emitting LASER sources at 2 µm remains limited or non-existent. The work carried out in this thesis focuses initially on the search for new compositions derived from the Ga2O3 - Gd2O3 - Nb2O5 phase diagram. The various heavy oxides have the required physico-chemical properties for optical applications and the generation of new emission wavelengths in the mid-infrared. Among the compounds synthesized by the solid route and, in some cases, by a co-precipitation liquid route, the rare earth niobate Gd3NbO7 caught our attention because of its potential spectroscopic properties, which are similar to those of another niobate already studied, Y3NbO7. Although the gadoniulm niobate suffers from structural instabilities that are detrimental to its production as a transparent ceramic, a non-stoichiometric composition structurally stable to temperatures up to 1600 °C or higher has been obtained. The study of the Gd3+xNb1-xO7-x□1+x solid solution, using Eu3+ photoluminescence as a structural probe and various characterization technics have shown the importance of the role of oxygen vacancies in the structural transition-stabilization phenomenon. This point is also illustrated by a comparative study of the sintering behavior of stoichiometric (x = 0) and non-stoichiometric (x = 0.25) niobates, where the influence of chemical composition and crystalline structure have a clear impact on the niobates sinterabillity. A first Gd3,25Nb0,75O6,75□1,25 :Ho3+ transparent ceramic has been obtained using a two stage-sintering process: natural sintering and post-HIP treatment. Their optical and luminescent properties have been collected.
ED Droit
Legal protection of adults : Comparative study between French, Egyptian and Kuwaiti laws.
by Meshal ALTHAFIRI (INSTITUT DE RECHERCHE EN DROIT DES AFFAIRES ET DU PATRIMOINE)
The defense will take place at 14h00 - Salle des thèses 16, avenue Léon Duguit, 33608 Pessac
in front of the jury composed of
- Jean-Marie PLAZY - Professeur - Université de Bordeaux - Directeur de these
- Gulsen YLDIRIM - Professeure - Université de Limoges - Rapporteur
- Gilles RAOUL-CORMEIL - Professeur - Université de Caen - Rapporteur
- Marie LAMARCHE - Professeure - Université de Bordeaux - Examinateur
- Meshal HAYAT - Maître de conférences - Université du Koweït - Examinateur
The law of protected persons is presented today in France, as a topical subject of current events by occupying a considerable space in the round tables of French lecturers, researchers and jurists. The subject of protected person law has always been a hot topic in Kuwait. The peculiarity of the legislative system of this country, declaring in its constitution as a Muslim country whose Islamic law is one of the main sources of its legislation, comes from the combination, often problematic, between the latter and the two other major sources that are 'Common Law' and Germanic civil / Roman law. The evolution of Kuwaiti laws in force is an omnipresent necessity which is imposed every time the legislator faces the evolution of society. Among the Gulf countries, Kuwait was one of the first has always expressed its desire to follow social and economic developments on an international scale, drawing inspiration from the Western example of which France constitutes one of the most interesting figures. , especially at the legislative level. The title of such work could be 'Legal protection of adults.' This thesis aims to compare French, Egyptian and Kuwaiti laws. Especially since the three rights do not provide the same guarantees, despite their claim to guarantee this protection. With regard to French law, with its multiple sources: internal, community and international law, it has established a solid and rich system, endowed with real means and a series of public and private institutions ensuring legal protection adults. However, the system is far from perfect. Efforts are still being made at all levels to fill the remaining gaps. Kuwaiti law and Egyptian law, for their part, have fairly recent systems, the sources of which come mainly from Muslim law, the civil code and international conventions. It will be interesting to compare how the Kuwaiti, Egyptian and French systems provide and guarantee legal protection for adults. What guarantees are provided by the three legislators? What are the problems experienced by the three societies despite the particularity of each, in particular the Kuwaiti whose two thirds of the population are foreigners?