ED Sciences Chimiques
Magnetochiral nanocomposites: from natural to synthetic strategies towards the observation of the magnetochiral dichroism phenomenon
by Matheus MENDES (Institut de Chimie & de Biologie des Membranes & des Nano-objets)
The defense will take place at 14h00 - B6 Amphiteather Institut Européen de Chimie et de Biologie (IECB) - 2 Rue Robert Escarpit 33607 PESSAC FRANCE
in front of the jury composed of
- Emilie POUGET - Directrice de recherche - Université de Bordeaux - Directeur de these
- Wiktor LEWANDOWSKI - Professeur - Faculty of Chemistry, University of Warsaw - Rapporteur
- Cornelia MEINERT - Directrice de recherche - Institut de Chimie de Nice (ICN/CNRS UMR7272) - Examinateur
- Elizabeth HILARD - Directrice de recherche - ICMCB – UMR5026 - Examinateur
- Mathieu GONIDEC - Chargé de recherche - ICMCB – UMR5026 - Examinateur
- Miguel COMESANA-HERMO - Chargé de recherche - ITODYS - Université Paris Cité - Rapporteur
In this project, magnetochiral nanocomposites will be studied to detect their response to circular dichroism (CD), magnetic circular dichroism (MCD) and potentially magnetochiral dichroism (MChD). In simplified words, MChD is a cross effect between natural circular dichroism (NCD) observed in chiral materials, and magnetic circular dichroism (MCD) observed in simple achiral magnetic materials. MChD is typically studied in the UV-visible region on single crystals, where the magnetic and chiral properties are situated on the same site, typically metal-based transitions in chiral coordination complexes, of which several examples are known in literature. On the other hand, MChD on the nanoscale has been rarely studied, even if self-assembly of chiral objects tends to enhance the chiral response, compared to that of discrete molecules. Therefore, this Ph.D. project aims to develop strategies to synthesize magnetochiral- responsive synthetic systems and explore alternative natural materials as models to compare with those synthetic materials. Four strategies are envisaged, two of them based on synthetic nanostructures and the others on natural-based materials. The first approach (I) counts on using a helical silica nanotemplate that is intrinsically chiral by its morphology to act as a chiral template for the growth of magnetic NPs, as we expect that the helicoidal-shaped organization of the magnetic NPs can give origin to CD signals. The second approach (II) counts on the synthesis of Cobalt (II) and Nickel (II) single magnetic NPs by classical coprecipitation technique in the presence of chiral ligands, we expect that the functionalization of the magnetic NPs with the chiral ligand can induce chirality to the core of the nanoparticle by creating some kind of distortion/asymmetry on the vicinity of the crystalline structure. Among the chosen natural materials, the third approach (III) concerns the use of possible natural magneto chiral responsive material such as magnetotactic bacteria (BMT) since that is a living organism that intrinsically possesses chirality and because of its ability to synthesize magnetic NPs (Magnetite – Fe3O4) by biomineralization. Finally, the forth approach (IV) concerns the use of chiral functionalized clay minerals with amino acids as nanotemplates for the growing of magnetic NPs, originating an overall magnetochiral interlayered nanostructure.
Synthesis and densification of zirconia at low temperature : A synergy between chemistry and sintering
by Yoan DENIS (ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux)
The defense will take place at 14h00 - Amphithéâtre de l'ICMCB 87 Avenue du Dr Albert Schweitzer, ICMCB, 33600, Pessac, France
in front of the jury composed of
- Catherine ELISSALDE - Directrice de recherche - ICMCB - Directeur de these
- Anne LERICHE - Professeure des universités - Université Polytechnique des Hauts-de-France - CERAMATHS - Rapporteur
- Capucine SASSOYE - Maîtresse de conférences - Sorbonne Université - LCMCP - Rapporteur
- César STEIL - Ingénieur de recherche - LEPMI - Examinateur
- Cyril AYMONIER - Directeur de recherche - ICMCB - Examinateur
- Gilles PHILIPPOT - Maître de conférences - Université de Bordeaux - ICMCB - CoDirecteur de these
In the light of today's economic and ecological challenges, reducing the energy cost of ceramic forming processes is a major challenge for society. In this context, reducing sintering temperatures is a major challenge. In addition to environmental considerations, it also addresses the need to optimize the properties of (multi)materials by controlling their microstructure, and to develop ceramic/metal or ceramic/polymer composites or assemblies. In this context, yttria-stabilized zirconia is a material of major interest. Its remarkable properties (mechanical, ionic conduction, optical) have resulted in numerous applications in a wide range of fields (biomedical, aeronautics, energy, etc.). Conventionally, yttria-stabilized zirconia is sintered at high temperatures (~1400°C), but the development of non-conventional sintering processes has enabled these temperatures to be significantly reduced. It is now possible to densify yttria-stabilized zirconia by Spark Plasma Sintering (SPS) at temperatures of ~1100°C. To further lower sintering temperatures, solvent-assisted processes have been developed over the past fifteen years. Hydro/solvothermal sintering and the Cold Sintering Process (CSP) enable to densify many materials at temperatures below 300°C. Optimal densification of zirconia, however, remains unattainable using these processes alone, with an average relative density of ceramics reported in the literature around 65%. The aim of this thesis is to optimize the low-temperature densification of zirconia and yttria-stabilized zirconia, mainly by hydro/solvothermal sintering and/or CSP. Two strategies focusing on chemistry and powder reactivity have been developed. The first is based on the use of yttria-stabilized zirconia nanoparticles synthesized in supercriticals fluids medias, where the sizes (<10 nm) and crystallinity of the nanoparticles obtained are assumed to enhance reactivity with regard sintering. resulting powders were tested using two unconventional processes: csp sps. second strategy is based on use reactive precursors such as yttrium zirconium hydroxides or oxo-hydroxides, which sintered by hydro>
ED Droit
The evolution of divorce in Malian law : a comparative study
by Mamady BAH (CENTRE EUROPÉEN DE RECHERCHES EN DROIT DES FAMILLES, DES ASSURANCES, DES PERSONNES ET DE LA SANTÉ)
The defense will take place at 14h00 - salle des thèses Campus de Pessac, 16 avenue Léon Duguit, 33608 Pessac.
in front of the jury composed of
- Marie LAMARCHE - Professeur - Université de Bordeaux - Directeur de these
- BOUBOU KEITA - Professeur - Université de Bamako - Rapporteur
- Maryline BRUGGEMAN - Maître de conférences - Université de Toulouse Capitole - Rapporteur
- Philippe DELMAS SAINT-HILAIRE - Professeur - Université de Bordeaux - Examinateur
In an effort to develop divorce law, the Malian legislator has, through Law no. 2011-087 of 30 December 2011 on the Code of Persons and the Family, proceeded with its liberalization with a view to giving more freedom to spouses wishing to dissolve their union. To this end, the path chosen by the Malian legislator was the diversity of divorce cases, as it was also the case in French legislation with Law no. 75-617 of July 11, 1975, maintained and refined by that of May 26, 2004, but also in certain sub-regional laws such as Senegalese (law no. 72-61 of June 12, 1972) and Beninese (law no. 2002-07 of August 24, 2004). In addition to divorce-sanction, the Malian legislator has introduced two new cases of divorce: divorce by mutual consent and divorce for breakdown of life together. In parallel with its policy of liberalization of divorce, the Malian legislator has also attempted to de-dramatize it. In this sense, an important place was given for the first time to the will of the spouses in the settlement of the effects of divorce and to the objective determination of the marriage breakdown. The disconnection of certain effects of divorce from the notion of fault also contributes to this policy of de-dramatizing divorce. The fundamental idea of such a reform of divorce law lies in the will of the Malian legislator, following the example of the French legislator of 1975, to adapt divorce law to conjugal realities, to empower the spouses, to promote individual freedom within the conjugal cell and to de-dramatize divorce. But have these objectives been achieved? A few years after the adoption of the Code of Persons and the Family, we generally observe an obvious failure of the liberalization policy and a mixed de-dramatization of divorce. This observation leads us to proceed with a profound adjustment of divorce law, with the aim of enshrining for the benefit of the spouses, a right to peaceful divorce, respectful of international commitments and family public order in Malian law.
ED Sciences et environnements
Platinum contamination trajectory in french hydrosystems since the beginning of the 20th century: a multi-scale spatio-temporal approach
by Maxime CHASTANET (Environnements et Paléoenvironnements Océaniques et Continentaux)
The defense will take place at 14h00 - Amphithéâtre B18N Allée Geoffroy Saint Hilaire Bâtiment B18N 33615, Pessac
in front of the jury composed of
- Jörg SCHÄFER - Professeur - Université de Bordeaux - Directeur de these
- Sebastien RAUCH - Full professor - Chalmers University of Technology - Rapporteur
- Jérôme VIERS - Professeur - Université Toulouse III - Paul Sabatier - Rapporteur
- Charlotte CATROUILLET - Maîtresse de conférences - Institut de Physique du Globe de Paris - Examinateur
- Liliane JEAN-SORO - Chargée de recherche - Université Gustave Eiffel - Examinateur
- Frédérique EYROLLE - Senior Researcher - Autorité de Sûreté Nucléaire et de Radioprotection - Examinateur
Platinum (Pt) is a critical element for technologies due to its scarcity and recent uses. These new uses, particularly in catalytic converters for combustion vehicles and in pharmaceutical compounds used in chemotherapy, led to an increase in Pt releases into the environment, making it an emerging contaminant. However, the temporal evolution (or trajectory) of Pt concentrations in river environments remains poorly understood, requiring multi-scale approaches, both spatial and temporal. Sediment cores collected downstream of major French rivers have been used to analyze Pt trajectories since the 20th century and define baseline levels in the sediments of the Garonne, Loire and Rhône Rivers, ranging from 0.6 to 1.6 µg kg-1. An historical Pt contamination was also revealed in the Seine River (> 10 µg kg-1), linked to industrial activities during the 20th century. Since the 2000s, emerging Pt signals have been observed in the Loire and Rhône Rivers while the legacy of historical contamination tends to mask this emergence in the Seine River. Estimated fluxes show that the Rhône River exports 21 kg yr-1 of particulate Pt, compared with ~2 kg yr-1 for the Loire and Seine Rivers. Sediment cores are therefore essential tools for characterizing the Pt temporal evolution in contrasting watersheds. For the Garonne River, it was not possible to find a site where a sediment core covering the last century could be collected. The analysis of its trajectory was made possible by coupling old deposits (<1950) from a sediment core and SPM taken from a monitoring network (~30 years) and selected to represent flood conditions. This approach allowed to (i) define a baseline for quantifying natural annual fluxes and (ii) identify anomalies and estimate anthropogenic fluxes that can be explained for most events by emissions from road traffic and/or cancer treatments. Other anomalies could not be explained, suggesting additional sources and/or processes to be investigated. In order to better identify the Pt sources and transfer processes, one strategy was to change scale by focusing on a small urban river draining the Bordeaux Metropole area (Jalle de Blanquefort), which had been monitored monthly for a year and sampled at high frequency during a storm event. This study demonstrates the role of meteorological conditions: under normal conditions, Pt is found mainly in dissolved form, supported by medical Pt discharges from WWTP. Under rainy conditions, Pt is mainly in particulate form, resulting from road runoff. This type of intense event (~4h) can contribute up to a third of the annual flux of particulate Pt, demonstrating the importance of monitoring first-flush waters. Based on general medical practices in oncology and the spatialization of cancer incidence and treatment data, a conceptual model of medical Pt emissions (Ptmed) was developed. The emissions distribution could be influenced not only by population density, but also by an age group (> 60 years old), particularly on the coast and in major cities. It is estimated that 67 % of the Ptmed national flux is emitted in the main hydrosystems, into which are discharged between 2 and 46 kg year-1 of Ptmed. As a first estimate, French hydrosystems may have exported 223 kg of Ptmed to coastal environments in 2023. This model will require adjustments to reduce uncertainties, spatialization of incidence data, WWTP treatment efficacies, and Ptmed reactivity along the land-sea continuum.
ED Sociétés, Politique, Santé Publique
Staying true to your commitment. Trajectories of left wing abertzale activists who have spent time in prison.
by Lauréna HAURAT--PEREZ (Centre Emile Durkheim)
The defense will take place at 14h00 - Salle des conseils 3 ter place de la victoire 33076 Bordeaux
in front of the jury composed of
- Xabier ITCAINA - Directeur de recherche - Sciences Po Bordeaux - Directeur de these
- Francis JAURéGUIBERRY - Professeur émérite - Université de Pau et des Pays de l'Adour - Rapporteur
- Natacha CHETCUTI-OSOROVITZ - Maîtresse de conférences - Centrale Supélec - Examinateur
- Sophie DUCHESNE - Directrice de recherche - Science Po Bordeaux - Examinateur
- Éric AGRIKOLIANSKY - Professeur des universités - Université Paris Dauphine - Rapporteur
- Razmig KEUCHEYAN - Professeur des universités - Université Paris Cité - CoDirecteur de these
The effects of imprisonment on political commitment are manifold and depend on a number of variables that have yet to be explored in the context of the Basque conflict. Based on the life histories of 42 former Basque political prisoners living in the North Basque Country, this thesis identifies their paths of commitment after prison. Most of the people we met had belonged to ETA or Iparretarrak and the length of their prison sentences varied from one month to several decades. What happens to the activist commitments of those imprisoned in connection with the Basque conflict once they are released from prison? The thesis analyses the careers of former Basque political prisoners chronologically, and is structured in three parts. The first looks at the beginnings of militant careers in legal activism, followed by a cartography of the different ways in which people join armed political organisations. The second part is part of a body of work that examines the prison experience. While a superficial homogeneity may appear at first glance when analysing the ways in which people experience confinement, singularisation variables emerge. Depending on the historical sequence of the conflict, the personal situation at the time of arrest, parenthood and gender, prison experiences take different forms and reveal a variety of ways of experiencing confinement. Finally, the third section analyses the various post-prison commitment paths. After explaining the conditions necessary for resuming underground activities after an initial period of imprisonment, the next two chapters shed light on the many ways in which activism is practised and the different spheres of involvement. Finally, the question of the Aiete process underway since 2011 is analysed in the light of the tensions and divergences already present for activists in the 1980s.