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Marvilliers, Sandrine. "Synthèses, caractérisations et études du comportement en oxydation de complexes dinucléaires fer-oxo et manganèse-oxo d'intérêt biologique". Paris 11, 1999. http://www.theses.fr/1999PA112302.
Pełny tekst źródłaFernandez, Rojo Lidia. "Vers un traitement passif des drainages miniers acides (DMA) riches en arsenic par oxydation biologique du fer et de l'arsenic". Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTT153.
Pełny tekst źródłaAcid mine drainage (AMD) are produced by sulfuric tailings from mining of metal ores. They are characterized by high contents of toxic elements like arsenic. One efficient and economical solution for the treatment of As in these tailings could be the use of a passive method based on iron and arsenic bacterial oxidation, and the subsequent precipitation of these elements in a stable form. In this context, the objective of this PhD thesis was to better understand the environmental and operational factors controlling the efficiency of As removal processes. A continuous-flow pilot approach was implemented in order to better reproduce the real treatment conditions. This study was first performed in a bench-scale bioreactor with controlled conditions (temperature, light, flow, residence time and water height). Then, it was performed in a field-scale bioreactor installed in situ, reproducing a passive treatment in real conditions. These devices were fed with As-rich AMD waters from the ancient mine of Carnoulès (Gard, France). Water and bioprecipitate properties were monitored in both devices, specially the redox speciation of iron and arsenic. This monitoring was held for different environmental and operational conditions. Iron and arsenic speciation in liquid and solid phases was measured by different analytical techniques such as HPLC-ICP-MS, EXAFS and XANES. Mineral identification was made by XRD analysis, while microbiological characterization was made by ARISA, high-throughput sequencing of 16S rRNA gene, and aioA gene quantification. Results from the lab-scale experiments evidenced the effects of the different operational parameters (water height, hydraulic retention time and the presence/absence of a floating film) on the treatment performance, as well as on the microbiology and mineralogy of the produced bioprecipitates. The field device was used to test the treatment performance under fluctuating environmental conditions (variability of the physico-chemistry of the feed water and of the temperature) and to gain new knowledge about the evolution of the bioprecipitates during six months of treatment. All the knowledge acquired in this PhD thesis could serve as a basis for the design of an arsenic removal stage in DMA treatment processes
ABALEA, VALERIE. "Etude des dommages oxydatifs de l'adn et de leur reparation dans les hepatocytes en culture traites par le fer : effet chimioprotecteur du flavonoide myricetine (doctorat : sciences biologiques et sante)". Rennes 1, 1999. http://www.theses.fr/1999REN1BO49.
Pełny tekst źródłaBondet, Vincent. "Oxydation de l'acide linoléique initiée par le système fer (II) / acide ascorbique en milieu dispersé : Mécanismes réactionnels et modes d'action de quelques antioxydants phénoliques". Compiègne, 1999. http://www.theses.fr/1999COMP1187.
Pełny tekst źródłaThe antioxidant behaviour of phenolic compounds depends on several factors with the structure of the medium playing a major part. The inhibition effects of 17 phenolic compounds on the oxidation of linoleic acid dispersed in an aqueous phase were studied. Conjugated dienes typically formed during the fust step of oxidation, and volatile compounds coming frOID the decomposition ofhydroperoxides, were monitored simultaneously in this study. The iron-ascorbate system was used as oxidation initiator and the experimental conditions were first adjusted. Mechanisms involving various active species were studied and appropriate concentration levels were chosen to achieve a simple and exploitable response. Ln that dispersed medium, a series of reactions and migrations of active species took place. The quick first step which was induced by the iron-ascorbate system was generated at the interface and gave way to a propagation step which took place in much deeper layers and which was characterised by a steady - rate for several hours. A relation between the efficiency of the studied antioxidants against the production of volatile compounds which are typical of rancidity and their ability to inhibit the formation of dienes was demonstrated. The relation between high antioxidant effect and apolarity has been established as in the 'polar paradox' firstly described by PORTER. This phenomena is explained by the concentration of non-polar compounds at the interface of the micelles. For similar polarities, antioxidant effect seemed to increase with the number of phenolic functions or groups able to chelate iron ions. To study the antiradical effect separately, the reduction of DPPH radical by three different antioxidants (BHT, eugenol and isoeugenol) in methanol was the method of choice. Bach molecule showed its own antiradical kinetics, reaction time, stoichiometry and reaction orders. Reactional mechanisms were proposed for each case
Miot, Jennifer. "Processus microbiens de biominéralisation et de détoxification des métaux/métalloïdes : oxydation du fer par des bactéries anaérobies neutrophiles et résistance au fer et à l'arsenic chez des eucaryotes unicellulaires de drainages miniers acides". Paris 7, 2008. http://www.theses.fr/2008PA077228.
Pełny tekst źródłaThis work aimed at studying the response of microorganisms to toxic elements, such as arsenic and to the lethal effects of mineral precipitation within cellular structures. We applied microscopic and spectroscopic tools adapted to the study of these organic-mineral assemblages. In a first section, we studied two different bacterial strains, both using Fe(II) as an electron donor under strictly anoxic conditions at neutral pH. The phototrophic strain SW2 precipitated iron on lipo-polysaccharidic fibres only at distance from the cells, whereas the denitrifying strain BoFeNl precipitated iron within its periplasm. Ultrafine cellular structures and proteins were preserved within these encrusted cells that can be considered as microfossils. In a second section, we studied unicellular eukaryotes from a Fe and As-rich acid mine drainage. Iron accumulation within the cells was shown to be completely decoupled from the processes of arsenic detoxification. Arsenic detoxification starts with As(V) reduction to As(III), followed by its complexation by thiol groups, involving the glutathione pathway and leading to its export from the cell. However, we show that As(V) was more toxic to the cells than As(III). Our results altogether provide new insights on the mechanisms of microbial biomineralization and detoxification of metals/metalloids and opens new perspectives for the search of biosignatures of specific metabolisms
Chakchouk, Mehrez. "Oxydation de la pollution organique aqueuse par l'oxygène moléculaire à haute température : effet promoteur de H2O2". Toulouse, INSA, 1993. http://www.theses.fr/1993ISAT0018.
Pełny tekst źródłaFakih, Mohamad. "Biogéochimie du fer et des éléments associés : Exemple de l'arsenic (V)". Phd thesis, Université Rennes 1, 2008. http://tel.archives-ouvertes.fr/tel-00578005.
Pełny tekst źródłaBardou-Jacquet, Édouard. "Surcharges en fer rares d’origine génétique : caractérisation clinique, fonctionnelle, et biologique". Thesis, Rennes 1, 2013. http://www.theses.fr/2013REN1S156/document.
Pełny tekst źródłaHFE related hemochromatosis (HH) is characterized by an increased plasma transferrin saturation level, which causes iron overload. These anomalies are due to low hepcidin secretion, the key regulator of iron metabolism, and define the hepcidin deficiency phenotype. New forms of iron overload with similar phenotype were identified, but their molecular mechanisms remain unclear. The main objective of this work was to characterize the clinical, functional, and biological aspects of rare genetic iron overload with an hepcidin deficiency phenotype. We firstly analyzed a cohort of HH patients, archetype of hepcidin-deficiency and showed that liver transplantation cured the disease, demonstrating the major role of the liver in the phenotype. We then characterized iron overloads with high transferrin saturation related to abnormalities of iron transport: i) we reported a fifth case of patient with DMT1 gene mutations and demonstrated the pathogenicity of the mutation p.Asn491Ser; ii) we described 12 patients with heterozygous mutation of the TF gene, leading to serum transferrin decrease. The increase of transferrin saturation associated to the disease does not seem to be related to a hepcidin-deficiency, and the presence of cofactors may facilitate iron overload. We then described the impact of mutations in the TFR2 gene, which induce hepcidin-deficiency whose expression is heterogeneous but that can occur in young peoples. Then we tried to clarify in vitro the mechanisms linking mutations in the TFR2 gene to an abnormal decrease of hepcidin and showed that the p.Asn12Ile and p.Gly430Arg mutations alter the TFR2 protein intracellular trafficking while the p.Arg768Pro mutation alters its interaction with transferrin. Being unable to induce expression of hepcidin in response to transferrin, unlike some authors, but in agreement with others, we were not able to analyze the impact of mutations on signal transduction toward hepcidin. Our results help to clarify the mechanisms involved in the development of iron overload in rare high saturation of transferrin
Courteix, Anne. "Modulation electrochimique de l'activité biologique de protéines à fer". Toulouse 3, 1991. http://www.theses.fr/1991TOU30167.
Pełny tekst źródłaFaye, Jérémy. "Oxydation du phénol en milieu aqueux par le peroxide d'hydrogène en présence d'oxydes de type pérovskite à base de fer". Poitiers, 2007. http://www.theses.fr/2007POIT2296.
Pełny tekst źródłaAccording to the drastic environmental legislation, advanced oxidation processes have been developed to satisfy the objectives in water depollution. Among these new technologies, catalytic wet hydrogen peroxide oxidation process allows to perform oxidation of organic pollutants in ambient conditions. The homogeneous Fenton system (Fe2+/H2O2), applied to industrial wastewater decontamination, could be advantageously improved by using stable heterogeneous catalysts more suitable for environmentally friendly processes. In this respect, perovskite type oxides (formula ABO3) behave as excellent candidates for the stabilization of the transition metal cation within the crystal structure, thereby limiting leaching of the active phase (i. E. Fe3+). In this work, a series of iron-based perovskites AFeO3 (with A = La, Nd, Pr, Sm, Y) was prepared by two different synthesis procedures, fully characterized and tested for the wet peroxide oxidation of phenol in aqueous solution. Relationship between the perovskites catalytic activity and stability and their physico-chemical properties (reducibility and textural characteristics) is highlighted. The most efficient catalysts were selected based on their ability to completely oxidize the organic pollutant in CO2 and on their stability in aqueous solution. A second series of non stoichiometric iron-based perovskites with general formula A1-xFeO3-δ (A = La, Pr and Sm and x = 0, 0. 1, 0. 2, 0. 3, 0. 4) was prepared in order to modulate the iron reducibility inside the perovskite network. The influence of this parameter on the catalytic activity was determined for various oxidation reactions in aqueous solution (phenol) and in gas phase (methane)
Buscail, Henri. "Etude de la corrosion du manganèse et d'alliages Fe-Mn ou Fe-Mn-Al dans des atmosphères oxydantes à hautes températures". Dijon, 1987. http://www.theses.fr/1987DIJOS024.
Pełny tekst źródłaCardey, Bruno. "Etude théorique des mécanismes d'oxydation de thiols en milieu d'intérêt biologique". Besançon, 2007. https://tel.archives-ouvertes.fr/tel-00435559.
Pełny tekst źródłaVériot, Gilles. "Métallo-récepteurs à structure cyclotrivératrylénique : conception, synthèse et études de leurs complexes du fer (II) et du fer (III)". Lyon 1, 1994. http://www.theses.fr/1994LYO10262.
Pełny tekst źródłaDuprat, Arthur. "Oxydation de composés aromatiques par le système Fer / Oxygène / Acide acétique". Phd thesis, Université Pierre et Marie Curie - Paris VI, 1991. http://pastel.archives-ouvertes.fr/pastel-00644964.
Pełny tekst źródłaLaunay, Franck. "Oxydation catalytique d'hydrocarbures en microemulsions inverses par des colloides de fer". Rennes 1, 1995. http://www.theses.fr/1995REN10095.
Pełny tekst źródłaMerceron, Gaëtan. "Comportement mécanique et oxydation d'alliages FeCrAl à haute température". ENSMP, 2000. http://www.theses.fr/2000ENMP1022.
Pełny tekst źródłaNiot, Isabelle. "Régulation de l'oxydation mitochondriale des acides gras dans le foie du rat Zucker obèse ou mince : effets de régimes enrichis en acides gras en n-3 : mise en évidence d'un mécanisme régulateur impliquant le réticulum endoplasmique". Dijon, 1991. http://www.theses.fr/1991DIJOS047.
Pełny tekst źródłaMartinez, Celis Mayerling. "Transformation de phases et comportement à l'oxydation d'alliages Fe-Al". Toulouse, INPT, 2007. http://ethesis.inp-toulouse.fr/archive/00000504/.
Pełny tekst źródłaThe numerous good properties of alloys based on Fe-Al compounds still make them good candidates for industrial applications (good strength, good oxidation resistance, low production cost). This thesis word focuses on two characteristics of such alloys: i) microstructural defects, with emphasis on defects linked to ordering and ii) high temperature oxidation. We have studied four different alloys : a binary Fe-40Al, two alloys with additional elements (Fe-40Al- 0. 01B and Fe-40Al-2. 7Ni-0. 02B) and a semi-industrial alloy (grade 3 including alloying elements – Ni, Mn, Cr, Mo, B – and Y2O3 particles). Diffusion couples were also elaborated between these alloys and iron, which allowed to study diffusion and produce specimens with a varying aluminium content. The microstructural characterisation helped us to determine the precise nature of the complex planar faults observed in boron containing alloys. The study of diffusion couples was performed by chemical analysis and by characterising by transmission electron microscopy the antiphase domains due to the ordering that occurred during thermal treatments. These results reveal the incidence of alloy composition on diffusion and transformation temperatures. We showed that nickel addition slows down diffusion kinetics and seems to expand the stability domain of B2 phase. Oxidation kinetics study has been achieved by thermo gravimetric analysis performed at 800 and 1000°C on the different Fe- l alloys and on specimens extracted from the diffusion couples. Mass gain results complemented by X ray diffraction and SEM observations allow determine the oxides formed depending on the specimen composition. We could show thus determine the minimum aluminium content needed to impede iron oxidation (19 at. %) and we highlighted the effect of nickel on oxidation kinetics
Duprat, François. "Oxydation de composes aromatiques par le systeme fer#0/oxygene/acide acetique". Paris 6, 1991. http://www.theses.fr/1991PA066102.
Pełny tekst źródłaBlondin, Geneviève. "Interaction d'echange, delocalisation electronique et couplage vibronique dans des complexes fer-soufre, fer-oxo et manganese-oxo d'interet biologique". Paris 11, 1992. http://www.theses.fr/1992PA112015.
Pełny tekst źródłaSuksaroj, Chaisri. "Nanofiltration et oxydation avancée de solutions de colorants : application au traitement d’éffluents de l’industrie textile". Montpellier 2, 2006. http://www.theses.fr/2006MON20077.
Pełny tekst źródłaXambeu, Isabelle. "Oxydation biologique du manganèse par les bactéries libres ou fixées, des eaux souterraines". Lyon 1, 1990. http://www.theses.fr/1990LYO10067.
Pełny tekst źródłaHADASCH, ANKE. "Oxydation biomimetique de polluants aromatiques polychlores catalysee par une tetrasulfonatophtalocyanine de fer(iii)". Toulouse 3, 1999. http://www.theses.fr/1999TOU30046.
Pełny tekst źródłaWidyanto, Bambang. "Oxydation à haute température de quelques alliages ferritiques : étude cinétique et morphologique". Compiègne, 1990. http://www.theses.fr/1990COMPD315.
Pełny tekst źródłaROSSI, CLAUDE. "Oxydation biologique et chimique de thioethers vinyliques : preparation de sulfoxydes chiraux a activites pharmacologiques". Clermont-Ferrand 2, 1993. http://www.theses.fr/1993CLF21468.
Pełny tekst źródłaEllis, Donald. "Enlèvement du fer et du manganèse de l'eau souterraine par oxydation et par microfiltration". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0027/MQ38077.pdf.
Pełny tekst źródłaCleiss, Jessica. "Réponse bactérienne au stress arsénié". Strasbourg, 2010. http://www.theses.fr/2010STRA6244.
Pełny tekst źródłaArsenic is a metalloid which is largely distributed in the environment. The implication of microorganisms in oxidoreduction reactions between the bioavailable As(III) and the less mobile As(V) oxidation states has been demonstrated. The heterotrophic bacteria, Herminiimonas arsenicoxydans, overcome the toxic effects of arsenic stress by either reducing arsenate (As(V)), or by oxidizing As(III). The reduction of As(V) has been largely studied, but the mechanism of oxidation of arsenite catalysed by arsenite oxidase is still unknown. In a first part, to identify genes possibly involved in the control of arsenite oxidation in H. Arsenicoxydans, a library of 10,000 mutants was constructed by transposon mutagenesis. Transposon insertions resulting in a lack of arsenite oxidase activity disrupted aoxA, aoxB, aoxRS, rpoN and dnaJ genes. In parallel, a differential transcriptome combined to a proteome analysis was performed. This functional analysis indicated that H arsenicoxydans expressed genes and proteins required not only for arsenic detoxification or stress response but also involved in motility, exopolysaccharide synthesis, phosphate import or energetic metabolism… However, no variation was found in the genes coding for arsenite oxidase. To address this process, physiological analyses coupled with Western immunoblotting experiments and DNA microarrays were used to examine the temporal changes in transcriptome profiles during the transition from As(III) to As(V) species due to As(III) oxidation. In a second part, the study was transposed to chemolithotrophic bacteria such as Thiomonas sp. And Rhizobium sp. NT-26. In these bacteria, the oxidation of As(III) is also catalysed by arsenite oxidase and As(III) can be utilized as electron donor. The analysis of the global response to arsenic stress, indicated that some mechanisms are conserved such as motility, phosphate import, arsenic resistance… and other are specific such as fatty acids biosynthesis, ABC-type transporters… Moreover, the involvement of AroR (AoxR) in the regulation of arsenite oxidase activity in a chemolitotrophic bacteria was validated in this work and others regulators were identified: PtxB and MoeB
Essoum, Hamida. "Oxydation à haute température des alliages Fe-Cr-Al : influence de l'humidité et rôle des précipités". Compiègne, 1996. http://www.theses.fr/1996COMPD876.
Pełny tekst źródłaAMEZIANE, JAMAL. "Interactions des cations metalliques fer et cuivre avec des nouveaux heterocycles azotes d'interet biologique". Reims, 1993. http://www.theses.fr/1993REIMS015.
Pełny tekst źródłaLAABASSI, MOHAMMED. "Utilisation de complexes organometalliques du fer pour des syntheses enantiocontrolees de molecules d'interet biologique". Rennes 1, 1991. http://www.theses.fr/1991REN10078.
Pełny tekst źródłaDefrance, Sabine. "Oxydations biomimétiques : modélisation de la manganèse peroxydase à l'aide de métalloporphyrines synthétiques associées à un donneur d'atome d'oxygène". Toulouse 3, 1993. http://www.theses.fr/1993TOU30029.
Pełny tekst źródłaGuyon, Ordonaud Claire. "Impact des traitements par hautes pressions sur l’oxydation des lipides et des protéines de la viande bovine". Nantes, 2016. http://www.theses.fr/2016ONIR085F.
Pełny tekst źródłaOne of the major health risks in the meat industry is contamination by spoilage bacteria and pathogens. It has been shown that treatments using high pressure are effective in limiting such contamination. However their impact on the organoleptic and nutritional properties of the meat are still not widely known (especially those related to oxidation reactions). The objective of this thesis was to evaluate the impact of high pressure treatments on health, sensory, and nutritional quality of ground beef, including storage by refrigeration after treatment
Sekkat, Chadia. "Participation des phénomènes oxydatifs dans l'activation des lymphocytes T et dans la synthèse d'IL2". Montpellier 2, 1988. http://www.theses.fr/1988MON20025.
Pełny tekst źródłaBorzeix, Conçais Frédérique. "Stratégie de mise en oeuvre de la biocatalyse en milieu organique : étude de la lipase et de l'alcool oxydase". Aix-Marseille 1, 1994. http://www.theses.fr/1994AIX11006.
Pełny tekst źródłaBertrand, Nathalie. "Prévision de la corrosion sèche des conteneurs de déchets radioactifs en condition d'entreposage : étude des mécanismes d'oxydation du fer à basse température et simulation numérique de la croissance d'une couche d'oxyde". Phd thesis, Toulouse, INPT, 2006. https://hal.science/tel-04576177.
Pełny tekst źródłaIn the framework of research on long term behaviour of radioactive waste containers, this work consists on the one hand in the study of low temperature oxidation of iron and on the other hand in the development of a numerical model of oxide scale growth. Isothermal oxidation experiments are performed on pure iron at 300 and 400°C in dry and humid air at atmospheric pressure. Oxide scales formed in these conditions are characterized. They are composed of a duplex magnetite scale under a thin hematite scale. The inner layer of the duplex scale is thinner than the outer one. Both are composed of columnar grains, that are smaller in the inner part. The outer hematite layer is made of very small equiaxed grains. Markers and tracers experiments show that a part of the scale grows at metal/oxide interface thanks to short-circuits diffusion of oxygen. A model for iron oxide scale growth at low temperature is then deduced. Besides this experimental study, the numerical model EKINOX (Estimation KINetics OXidation) is developed. It allows to simulate the growth of an oxide scale controlled by mixed mechanisms, such as anionic and cationic vacancies diffusion through the scale, as well as metal transfer at metal/oxide interface. It is based on the calculation of concentration profiles of chemical species and also point defects in the oxide scale and in the substrate. This numerical model does not use the classical quasi-steady-state approximation and calculates the future of cationic vacancies at metal/oxide interface. Indeed, these point defects can either be eliminated by interface motion or injected in the substrate, where they can be annihilated, considering sinks as the climb of dislocations. Hence, the influence of substrate cold-work can be investigated. The EKINOX model is validated in the conditions of Wagner's theory and is confronted with experimental results by its application to the case of high temperature oxidation of nickel
Cavazza, Christine. "La chaîne respiratoire entre le fer ferreux et l'oxygène chez Thiobacillus ferrooxidans : caractérisation de nouvelles protéines d'oxydoréduction périplasmiques". Aix-Marseille 1, 1996. http://www.theses.fr/1996AIX11065.
Pełny tekst źródłaMeunier, Florent. "Réactions d'oxydation catalysées par des complexes de ruthénium et de fer". Paris 11, 1986. http://www.theses.fr/1986PA112103.
Pełny tekst źródłaThis thesis presents new catalytic systems like: [M]/L/[O] : RuCl₃ ou FeSO₄L : 2,2’-bipyridine ou 1, 10-phénanthroline substituée [O] : NaOCl ou NaIO₄Cyclic or acyclic ethers ore oxidized into lactones or esters with yields up to 65 % with the catalytic system RuCl₃/NaOCl. The total degradation of a part of the ether into carbon dioxide led us introducing diimine ligands into the reaction to reduce the oxidizing power of the system. These ligands complexe the metal and resist to oxidation. Applying the system RuCl₃/L/NaOCl to alkenes gives epoxides. The formation of chlorinated products amongst the oxidation products led us putting NaIO₄ in place of NaOCl. Various alkenes are stereoselectively epoxidized with yields up to 83 % by means of RuCl₃/2,2'-dipyridyl/NaIO₄. Replacing 2,2'-dipyridyl by substituted phenanthrolines changes the reactivity of the catalytic system. A similar study was carried out with FeSO₄ instead of RuCl₃. The mechanism of these reactions is discussed and [M = 0] complex was set up as the catalyst
Bucciarelli, Eva. "Rôle du fer dans le contrôle de la pompe biologique de CO2 de l'océan austral". Brest, 2001. http://www.theses.fr/2001BRES2041.
Pełny tekst źródłaThis work concerns the role played by iron in controlling the CO2 biological pump in the Southern Ocean. Iron, indeed, is a micro-nutrient essential to life and numerous experiments have shown that its subnanomolar concentrations in the water column (co)-limited the primary production in various oceanic areas, e. G. In the Southern Ocean. The thesis is divided in two complementary parts, a geochemical part and a biogeochemical one. The geochemical part aims at a better understanding of the oceanic geochemical cycle of iron. It presents measurements of dissolved iron and manganese in the wake of the Kerguelen Islands (Bucciarelli et al. 2001) and of dissolved and total dissolvable iron in the open Southern Ocean (Crozet basin). The samplings were conducted as part of the Antares program (France JGOFS), during the Antares 3 cruise in the wake of the Kerguelen island, and during the Antares 4 cruise in the Crozet Basin. The data give insigths into the sources and sinks of iron in the Indian sector of the Southern Ocean. The biogeochemical part focuses on the effects of iron stress on natural phytoplanktonic community on one hand (Blain et al. 2001, Blain et al. 2002, Sedwick et al. 2002), and on laboratory monospecific cultures of three species of diatoms on the other hand. A decoupling between the cycles of silicon, carbon and nitrogen has been shown under iron stress conditions. The decoupling is quantified in a range of iron concentrations varying from iron-limiting to iron-sufficient conditions
Pierre, Céline. "Catalyse d'oxydation d'hydrocarbures par des complexes de fer et de manganèse à ligands macrocycliques azotés". Bordeaux 1, 2001. http://www.theses.fr/2001BOR12433.
Pełny tekst źródłaDrissi, Sidi El Hassane. "Oxydation des espèces du fer en milieu aqueux carbonate : préparation et propriétés thermodynamiques de l'hydroxyde carbonate Fe2+-Fe3+ en milieu aqueux (rouille verte 1 carbonatée) et sa formation directe à partir du fer métallique". Nancy 1, 1995. http://www.theses.fr/1995NAN10349.
Pełny tekst źródłaBayle, Sandrine. "Traitement d'effluents gazeux chargés en composés organiques volatils par oxydation biologique : approche écologique des communautés microbiennes". Lyon 1, 2005. http://www.theses.fr/2005LYO10106.
Pełny tekst źródłaCourty, Claudie. "Rôle du carbone et du manganèse lors de l'oxydation du fer a haute température. Interactions avec les éléments actifs cérium et yttrium". Dijon, 1997. http://www.theses.fr/1997DIJOS024.
Pełny tekst źródłaGuillaume, Patricia. "Influence de ligands bidentates sur les systèmes Fe-NO/Fe-NO2/Fe-NO3/O2 conçus pour l'activation et le transfert de l'oxygène moléculaire". Nice, 1990. http://www.theses.fr/1990NICE4410.
Pełny tekst źródłaKösem, Artemis. "Dépôt chimique de silicium et d'aluminium sur du fer à partir d'une phase gazeuse tenue à l'oxydation et à la sulfuration des revêtements obtenus". Lyon 1, 1985. http://www.theses.fr/1985LYO19038.
Pełny tekst źródłaZaidi, Mourad. "Mouillabilité de surfaces hétérogènes fer-oxydes par le plomb et l'étain". Châtenay-Malabry, Ecole centrale de Paris, 2008. http://www.theses.fr/2008ECAP1094.
Pełny tekst źródłaWetting phenomenon takes place in several processes among which continuous galvanizing of steel sheet for car bodies. In this process, the steel sheet is immersed in a zinc bath in order to cover it with a protective zinc layer. But before that, the cold rolled steel sheet is annealed in a reducing atmosphere in order to eliminate the cold working and the superficial iron oxides improving thereby the galvanizing reactions. New steels, called advanced high strength steels, have been developed in order to improve vehicle safety without increasing their weight and therefore fuel consumption. These steels contain high amounts of oxidable alloying elements that segregate during the annealing to the surface where they form oxides particles that are not wetted by liquid zinc. Therefore it seems important to understand the wetting by liquid metals of heterogeneous surfaces composed by metallic iron and oxides. For this purpose we have build a dispensed drop apparatus allowing the annealing of the substrate separately of the liquid and the in situ study of the spreading of metallic droplet at very short time using a high speed camera. In our experiments we have used different iron – silcon alloys and an industrial steel leading to surface coverage lying from 0 to 100%. We have chosen two liquid metals. Lead to investigate the non reactive wetting and tin to investigate the reactive wetting. Wetting
Gref, Aurore. "Activation de la liaison C-H : oxydation des hydrocarbures saturés en présence de catalyseurs de fer par l'oxygène moléculaire, activé électrochimiquement". Paris 11, 1986. http://www.theses.fr/1987PA112021.
Pełny tekst źródłaBy modifying the so-called "Gif" chemical system we established on electrochemical one for oxidation of saturated hydrocarbons. This system hos the cluster FeII FeIII 2o(OAc)6PY3. 5 as catalyst and comprises pyridine, an acid (trifluoroacetic or 2-picolinic) and molecular oxygen activated at the cathode. After having analysed the electrochemical behoviour of each of the components of the systems by cyclic voltammetry we were in a position to chose the optimum conditions under which to work. Were obtained a similar selectivity with the electrochemical system as with the chemical one: attach occurs preferentially at the secondary C-H bond and results in the preponderant formation of ketones and an efficiency (electronic yield) which is clearly superior (con reach 70% in the case of cyclohexane). Use of hydrogen peroxide resulted in same selectivity as that obtained by molecular oxygen activated at the cathode in the presence of on acid, although with lower yields. This lead us to propose that the some active species were involved in the two processes. The latter might be on iron-oxo species of low oxidation state, and the presence of pyridine as ligand might confer a particular selectivity to it different to that observed in other systems
MORICE, CHRISTOPHE. "Complexation, oxydation et reconnaissance chirale des amino esters par les porphyrines du ruthenium et du fer". Rennes 1, 1998. http://www.theses.fr/1998REN10036.
Pełny tekst źródłaTrehoux, Alexandre. "Synthèse de complexes binucléaires de fer pour activation réductrice du dioxygène : vers de nouveaux catalyseurs d'oxydation bio-inspirés". Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS052/document.
Pełny tekst źródłaThis work describes the synthesis and the study of the reactivity of diiron complexes, developed in order to mimic the catalytic activity of diiron enzymes such as the soluble methane monooxygenase. We synthesized and characterized several diiron(III) complexes, bearing different types of groups (electron-donating, electron-withdrawing, hydrogen bond donating) in their second coordination sphere, in a symmetrical or non-symmetrical way. We studied the influence of the second coordination sphere of these different complexes over the different intermediates (particularly the µ-peroxo-FeIIIFeIII intermediate) formed by exposing them to hydrogen peroxide. We also studied the ability of these complexes to catalyze the oxidation of various substrates (sulfurs, alkenes, alkanes) by hydrogen peroxide, in absence or in presence of water in the reaction mixture. An interesting modification of chemoselectivity was observed in the case of oxidation of cyclooctene by hydrogen peroxyde, catalyzed by a non-symmetrical diiron complex, in presence of water in the reaction mixture. Several mechanistic studies were performed in order to investigate on the origin of the phenomenons we observed during oxidation catalysis studies
Boualam, Mohamed. "Oxydation d'alliages FeCrAl : influence de quelques facteurs sur la structure et la morphologie des couches formées". Compiègne, 1992. http://www.theses.fr/1992COMPD465.
Pełny tekst źródłaThomas, Fabrice. "Complexation du fer par des ligands tripodes originaux et la calcéine : étude thermodynamique, cinétique et biologique". Université Joseph Fourier (Grenoble), 1999. http://www.theses.fr/1999GRE10108.
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