Tesis sobre el tema "Caractérisations physiques et chimiques"
Crea una cita precisa en los estilos APA, MLA, Chicago, Harvard y otros
Consulte los 50 mejores tesis para su investigación sobre el tema "Caractérisations physiques et chimiques".
Junto a cada fuente en la lista de referencias hay un botón "Agregar a la bibliografía". Pulsa este botón, y generaremos automáticamente la referencia bibliográfica para la obra elegida en el estilo de cita que necesites: APA, MLA, Harvard, Vancouver, Chicago, etc.
También puede descargar el texto completo de la publicación académica en formato pdf y leer en línea su resumen siempre que esté disponible en los metadatos.
Explore tesis sobre una amplia variedad de disciplinas y organice su bibliografía correctamente.
Thierry-Jebali, Nicolas. "Caractérisations et modélisations physiques de contacts entre phases métalliques et Nitrure de Gallium semi-conducteur". Phd thesis, Université Claude Bernard - Lyon I, 2011. http://tel.archives-ouvertes.fr/tel-00744661.
Texto completoLedoux, Frédéric. "Les aérosols particulaires atmosphériques sur le Dunkerquois : caractérisations chimiques, physiques, spectroscopiques et évaluation de leur toxicité". Littoral, 2003. http://www.theses.fr/2003DUNK0096.
Texto completoThe northern part of the France and especially the city of Dunkerque is subject to an intense and heavy industrial activity. This high industrialized city emits in the atmosphere about 13% of the french industrial total of particles. This study was done in this frame and the aim of this work is to characterize atmospheric aerosols in Dunkerque, to evaluate its influence upon nearest locations, and to test the toxicity of the particles. Results fromtwo seasonal sampling campaigns shows that mean atmospheric concentrations are in the same order than those of other North Sea sites, and this is the consequence of very favorable meteorological conditions. This study underlines that during specific meteorological conditions, impacts of emissions from urban sources can be much higher than those of the industrial park. Specific tracers of sources of emissions sources were investigated, and very positive results are obtained with Electron Paramagnetic Resonance spectroscopy. Measurements performed at about 15 km from Dunkerque shows that this industrial city influences atmospheric concentrations of some metals like Fe, Pb or Zn. Impact of atmospheric particules upon human pulmonary epithelial cells (L132) evidences that such particles produces an oxidative stress
Joudieh, Samer. "Biopolymères à base de cyclodextrines : Synthèse, caractérisations physico-chimiques et applications pharmaceutiques". Rouen, 2009. http://www.theses.fr/2009ROUES017.
Texto completoThis work of thesis relates to the synthesis and the physicochemical characterization of cyclodextrine polymers and for their use in the preparation of binary systems “CD-polymer/Drug”. The objective is to show the interest of these polymers innovating in the galenic formulation for potential applications in pharmaceutical field. The whole of this work makes it possible to conclude that the optimal conditions to obtain a maximum mass soluble polymer yield (40% mass/mass). We characterized obtained polymers by FT-IR, DSC, RX and by SEC/MALLS. Two drugs were retained as tracers: Albendazole, an insoluble pesticide, and Nimesulid, a non-steroidal anti-inflammatory drug, amphiphilic and ionizable in water. An important increase in intrinsic solubility for each of the two drugs was obtained thanks to cyclodextrin polymers. This increase in solubility is 100 times more important than that obtained with native cyclodextrins, while at the same time the quantities of polymers used were quite lower than those of native cyclodextrins. Two dosage forms were developed by using the binary systems “poly-CD/PA: pellets and capsules. The polymers of cyclodextrins play the part of excipients for these dosage forms with 95% of CD-polymers in the matrices intended for the filling of capsules and up to 40% to form the matrix of the pellets
Pees, Bernard. "Synthèse et polymérisation de monomères acryliques perfluorés : caractérisations physico-chimiques de leurs polymères". Metz, 2000. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/2000/Pees.Bernard.SMZ0056.pdf.
Texto completoA lot of studies showing the water-repellency of fluorine-containing polyacrylates were reported since 1950. A string connection between these surface properties and the structure of the polymers (bilayer organization of the perfluorinated lateral chains) has been demonstrated. The purpose of this work is the synthesis and the polymerization of new functionalized fluorine-containing acrylic monomers. Then physical and chemical properties of these compounds are investigated. In a firt part, we describe the synthesis of acrylic monomers bearing different kind of organic group (mesogenic group). Particularly, we investigate the free radical addition of perfluorinated mercaptans to [omega]-unsaturated alcohols and the Fisher esterification of β-hydroxyl sulfide with acrylic acid. In second part, the homopolymerization and copolymerization of the previous monomers is studied. Then, the results of physical and chemical properties determinations are detailed. The investigation of the changes of the thermal, strutural and surface properties of [omega]-perfluorooctyl-alkyl acrylates with the increasing of the number of methylen group into the lateral chains, shows an even-odd effect. Structural and thermal properties of fluorine-containing polyacrylates can be increased significantly by adding an organic group into the lateral chain. The mesogenic group effet of these moieties is demonstrated. Finally, a sulfonated monomer is copolymerized with butyl acrylate in one hand and in second with stearyl crylate. The two copolymers water-repellencies are investigated and compared to commercial compounds. The good results obtained and the quite simple synthesis of this monomer, afford a possible commercial use
Ollivrin, Xavier. "Nouveaux sels de lithium à fonctions plastifiante et polaire : caractérisations physico-chimiques et électrochimiques en milieu polymère". Grenoble INPG, 1999. http://www.theses.fr/1999INPG0057.
Texto completoDien, Eric. "Elaboration par voie chimique et caractérisations physiques de films minces à base de matériaux ferroélectriques du type Ba1-xSrXTio3". Limoges, 1999. http://www.theses.fr/1999LIMO0016.
Texto completoMontes, de Oca Valero Arturo Javier. "Elaboration du carbure et du nitrure de titane par ds procédés chimiques et physiques en phase vapeur : caractérisation de la microstructure". Phd thesis, Université Sciences et Technologies - Bordeaux I, 2002. http://tel.archives-ouvertes.fr/tel-00007441.
Texto completoMontes, De Oca-Valero Javier-Arturo. "Élaboration du carbure et du nitrure de titane par des procédés chimiques et physiques en phase vapeur : caractérisation de la microstructure". Bordeaux 1, 2002. http://www.theses.fr/2002BOR12582.
Texto completoBourdette, Béatrice. "Durabilité du mortier : prise en compte des auréoles de transition dans la caractérisation et la modélisation des processus physiques et chimiques d'altération". Toulouse, INSA, 1994. http://www.theses.fr/1994ISAT0030.
Texto completoNouet, Julius. "Caractérisations physico-chimiques des biominéraux carbonatés de Mollusques actuels et fossiles : le cas des structures entrecroisées". Phd thesis, Université Paris Sud - Paris XI, 2014. http://tel.archives-ouvertes.fr/tel-00984962.
Texto completoJeanneau, Justin. "Synthèse et propriétés physiques sous haute pression de composés à base de Cr4+". Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAY088.
Texto completoAfter 25 years of research on the superconducting cuprates, the discovery of high Tc superconductivity in related iron based pnictides in 2008[1] has stimulated the search of new superconductors. In particular antiferromagnet (AFM) with high Néel temperature, moderate magnetic moments and with crystallographic 2D layers could be adequate parent phases for new unconventional superconductors. In particular, other systems with 3d transition elements are very interesting systems for potential new high Tc superconductors.In this context we have reinvestigated the physical properties of n=1, 2,3 and + members of the Srn+1CrnO3n+1Ruddlesden Popper (RP) series. We have successfully synthesized at HP-HT Sr2CrO4 (n=1), Sr3Cr2O7(n=2), Sr4Cr3O10 (n=3) and SrCrO3 (n=infinite). We present some results of several studies performed on these phases such as neutron powder diffraction, Synchrotron X-ray diffraction under high pressure and low temperature, electrical transport properties under high pressure. Even if no superconductivity was observed, interesting properties had been discovered such as an unusual “anti-Jahn-Teller” in Sr2CrO4 at low temperature or an orbital ordering in Sr3Cr2O7.To explore new Cr-based systems where superconductivity could potentially be induced by changing Cr-Cr interactions in the Sr2CrO4 and Sr3Cr2O7RP phases, new chromates have been synthesized under HP-HT by substituting Sr2+ with other alkaline earth elements in order to “play” with the cation size effect. For the n=1 RP Ca2CrO4 phase, substitution with Ca2+ as a replacing element lead to a weakening of both the insulating behavior and AFM ordering. Synthesis to form the n=2 RP Ca-based lead to the formation of the unexpected and new n=3 phase Ca4Cr2O10.Ba2+ as a replacing element broke the RP structure configuration and led to a new phase, whose crystal structure was solved using electron diffraction tomography.In 2014, superconductivity has been discovered in CrAs (Tc=2.2K at P=0.8GPa), the first superconducting Cr-based system. In this context, we have look for other AFM Cr-based system with relatively high Néel temperature and moderate Cr magnetic moment. In consequence, we investigated another system, the narrow-gap semiconductor CrSb2. We find a metal-insulating transition from transport measurement at 10 GPa for both polycrystalline and single crystals samples we synthesized. At this pressure, we also observed a phase transition on synchrotron XRD under pressure. Finally, pressure dependence of the AFM ordering had been established by NPD under high pressure
Péru, Laurence. "Caractérisations physico-chimiques des phases minérales de calcifications ectopiques : application à la transformation biologique de phosphates de calcium". Châtenay-Malabry, Ecole centrale de Paris, 1993. http://www.theses.fr/1993ECAP0325.
Texto completoMollet, Chloé. "Identification et caractérisations physico-chimiques et pharmacologiques de nouvelles molécules bioactives isolées à partir de venins d’animaux : exemple des peptides antimicrobiens". Electronic Thesis or Diss., Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0352.
Texto completoThe research for new bioactive molecules which can be used in therapeutic is a major public health issue, particularly in the treatment of certain diseases such as bacterial infections.The natural resistance of bacteria consecutive to overuse of antibiotics have resulted in the selection of pathogenic multi-drug resistant bacteria. Over the last few decades, resistance to conventional antibiotics has limited treatment options, resulting in a significant increase in mortality and morbidity in hospitals. Moreover, since 1970, only two new classes of antibiotics have been placed on the market. Venoms are known to be a rich source of unique and innovative pharmacologically active substances, such as antimicrobial peptides (PAMs), which represent an original alternative to small molecules for the development of new active and non-resistance inducing antibiotics.In our study, among the 200 venoms of animals studied for their antibacterial properties, at least six PAMs were isolated from an insect venom. The original peptide 1 inhibits the growth of Gram positive and negative bacteria but shows a high hemotoxicity (TI = 1,6-3,2). The solid phase synthesis of structural analogs allowed to identify R1W8 and I1N11, less toxic (TI = 18 et >800 respectively). The preliminary results of the action mechanism study suggest that these peptides have a pore-forming action on bacteria cytoplasmic membrane. These peptides can be used as models for the development of new antimicrobial agents
Souidi, Ramzi. "Etudes des propriétés physiques et chimiques de la surface des substrats de Silicium après découpe dans les applications aux cellules solaires photovoltaïques". Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAY017/document.
Texto completoFor photovoltaic industry (PV), the optimization of cutting silicon ingot into wafers represents both an economic and a scientific issue. Economic challenge in that it is important to reduce the loss of material induced by cutting. Scientific issue in that it is necessary to understand the impact of sawing on the quality of silicon near the surface. This PhD research work aims to characterize the nature and extent of the damage generated by an innovative cutting technique using diamond wires. A major objective is to evaluate the thickness of the subsurface damage layer (called SSD). In order to characterize the SSD, physical and chemical investigations as a function of depth were performed on either as-cut surface, bevel or transverse sectioned samples or by removal of material by sequential etching in diluted solutions. Sample preparation protocols as well as many characterization techniques were used. In particular microscopy techniques (optical, confocal, electronic SEM and TEM), photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy and mechanical strength tests allow multiscale characterization of wafers and coupons. A low bevel angle polishing lets to extend the observation zone of deep defects and to make a statistical analysis. Furthermore, methods from measuring the minority carrier lifetime are used to evaluate the recombination processes on the disturbed layer. The lifetime was obtained by photoconductivity decay (PCD) measurements on SiNx: H and Al2O3 passivated surfaces obtained from PECVD and ALD deposition processes respectively. First, characterizing samples from as-cut wafers indicates that the major defects of the SSD are cracks generated by cutting and propagated into the subsurface. These cracks are distributed over varying and heterogeneous depths depending on the sawing conditions. Second, the results of the sequential removal method show, on the one hand, an effect of the SSD in recombination processes. The evaluation accuracy of this effect is conditioned by optimized surface passivation and reliable measurements of lifetime. On the other hand, an interaction of chemical attack with cracks is shown. This is crucial in the evaluation of the absolute thickness of SSD layer that may impact the solar cells performance
Mollet, Chloé. "Identification et caractérisations physico-chimiques et pharmacologiques de nouvelles molécules bioactives isolées à partir de venins d’animaux : exemple des peptides antimicrobiens". Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0352.
Texto completoThe research for new bioactive molecules which can be used in therapeutic is a major public health issue, particularly in the treatment of certain diseases such as bacterial infections.The natural resistance of bacteria consecutive to overuse of antibiotics have resulted in the selection of pathogenic multi-drug resistant bacteria. Over the last few decades, resistance to conventional antibiotics has limited treatment options, resulting in a significant increase in mortality and morbidity in hospitals. Moreover, since 1970, only two new classes of antibiotics have been placed on the market. Venoms are known to be a rich source of unique and innovative pharmacologically active substances, such as antimicrobial peptides (PAMs), which represent an original alternative to small molecules for the development of new active and non-resistance inducing antibiotics.In our study, among the 200 venoms of animals studied for their antibacterial properties, at least six PAMs were isolated from an insect venom. The original peptide 1 inhibits the growth of Gram positive and negative bacteria but shows a high hemotoxicity (TI = 1,6-3,2). The solid phase synthesis of structural analogs allowed to identify R1W8 and I1N11, less toxic (TI = 18 et >800 respectively). The preliminary results of the action mechanism study suggest that these peptides have a pore-forming action on bacteria cytoplasmic membrane. These peptides can be used as models for the development of new antimicrobial agents
Bonnefoy, Mickaël. "Recherche et caractérisation des propriétés physiques et chimiques des compagnons de faible masse, naines brunes et planètes géantes, à l'aide d'observations à haut contraste et à haute résolution angulaire". Grenoble, 2010. http://www.theses.fr/2010GRENY035.
Texto completoMy work takes place in the dynamic context of the direct detection of low mass companions (brown dwarfs, extrasolar planets). I intent to characterize their physical and chemical properties, and to understand the mechanisms that lead to their formation and drive their evolution. This requires using high contrast and high angular resolution techniques in order to resolve the close environment of the stars without being limited by their flux. I had the opportunity to participate to observational campaigns so as to detect new sources. I developed a set of data analysis tools designed to extract the spectra and the flux of the objects into photometric bands. Finally, I used this information to study the physical (radius, mass, age) and the atmospheric (composition, effective temperature, surface gravity) properties of these objects. The first part of this manuscript focus on the detection of young (age < 100 Myrs) low mass companions using imaging. I describe a set of reduction and analysis tools dedicated to the angular differential imaging technique. These tools have been used on data coming from the NaCo instrument located on the Very Large Telescope (Chile). They allowed re-detecting the extrasolar planet β Pictoris b. This companion is closer to its star than any of the extrasolar planets detected directly so far. This discovery brings the definite proof that giant planets can form in less than 12 million years within disks. I finally present a complementary analysis I conducted to initiate the characterization of this valuable object. The determination of the spectroscopic properties of young and low mass objects in the near infrared (1. 1-2. 5 µm) constitutes the second aspect of my work (and is reported in the last part of the manuscript). I started developing analysis and processing tools dedicated to data gathered on the adaptive optics assisted integral field spectrograph SINFONI. These efforts were used to analyze the spectrum of the planet/brown dwarf companion AB Pic b. This work was pursued to built a spectral library of young objects. This library brings a collection of reference spectra, necessary for the study of other young companions. It also brings new constraints on the latest generation of atmospheric models of cool objects. To conclude, I used the instrument NaCo and SINFONI to characterize the binary system TWA 22AB that could calibrate evolutionary models of low mass objects
Mohgouk, Zouknak Louis David. "Optimisation d'oxydes métalliques pour la réalisation d’électrode en adéquation avec le matériau photosensible dans l'infrarouge". Electronic Thesis or Diss., Université Grenoble Alpes, 2024. http://www.theses.fr/2024GRALT031.
Texto completoOver the past few decades, the development of zero-dimensional (0D) materials or quantum dots (QDs) has grown significantly. Among these materials, lead sulphide (PbS) QDs have received particular attention due to their outstanding properties, including tunable optical absorption from 600 to 2600 nm. PbS QDs are considered to be one of the most promising materials for the next generation of infrared sensors. There is therefore growing interest in their use in industrial applications. When these materials are integrated into optoelectronic devices, they require the use of efficient charge extraction electrodes, as well as a transparent electrical contact in the IR for better performance. In this thesis work, we studied the properties of hole extraction electrodes (HTL) based on transition metal oxides and the transparent electrical contact based on In2O3 (TCO or transparent and conductive oxide) prepared by sputtering. These studies were initially carried out on individual layers of TCO and HTL. Characterisation of the TCO films showed that hydrogen doping can improve their optical properties in the infrared region of the electromagnetic spectrum (the region of interest for the targeted applications). Secondly, in order to fabricate photodiode structures, they were integrated onto a film of PbS QDs deposited on an electrode optimised for electron extraction and transport. Appropriate characterisations have shown that ultra-thin NiOx films can be better alternatives to the MoOx layers traditionally used as hole extraction and transport materials on PbS QD films
El, Rhess Es-Saïd. "Synthèse, mode de croissance et caractérisations physico-chimiques de microparticules monodispersés de silice dans le système SI(OC : :(2)h::(5))::(4)-nh::(3)-h::(2)o-roh". Besançon, 1988. http://www.theses.fr/1988BESA2023.
Texto completoRey-Bayle, Maud. "Utilisation de la spectroscopie proche infrarouge multipoints couplée à de la chimiométrie pour la caractérisation en ligne de milieux diffusants". Thesis, Montpellier, 2017. http://www.theses.fr/2017MONTT097.
Texto completoThe aim of this thesis is to demonstrate the potential of multipoint near infrared spectroscopy to monitor online scattering and absorbing environments, where physical and chemical properties change over time. The work was first based on the study of an environment where scattering was the only parameter varying over time. Monitoring of the silica precipitation reaction has been chosen to illustrate that environment. First of all, spectra in collimated transmittance mode were acquired from samples collected during the process. Thanks to the Beer-Lambert law, scattering coefficients of each sample were obtained and from them the different steps of the reaction were found. A principal component analysis of those coefficients showed the existence of two scattering modes into the reaction environment. In the second phase, a multipoint probe was submerged in an industrial reactor. Spectra were measured during the precipitation with angle of 30°, 90°, 150°, 170° and 180° to the source. A univariate analyse at those different angles showed differences and similarities between the positions, linked to the interaction of light and matter. Then, a multiblock and multivariate analysis, CCSWA (Common Component and Specific Weight Analysis), was applied. It allows the combination of information from different angles and also shows common and specific information, in order to validate the use of multipoint measurement to monitor the process. Thanks to the analysis of global scores, different kind of scattering and the specificity of some angle, in the detection of physical modifications were identified. The analysis of individual loadings confirmed the identification of the different steps of reaction and has revealed some phenomena related to light scattering, such as the extension of the optical path. The same approach, analysis in the laboratory then online, was applied on an environment where scattering and absorption vary. Monitoring of products from the process to improve oil extraction, has been chosen to illustrate that environment. First of all, micro emulsions (water, oil and surfactant) were made so that physical and chemical properties would be different between samples. Then, each phase was analysed separately. A principal component analysis was used to characterize the system by phase identification. It also showed the differences between the phases were linked, both to absorption and scattering. In order to separate those two phenomena, a multivariate resolution by alternate regression has been applied. It has permitted to explain in more details the differences between the phases and to obtain semi-quantitative monitoring. Finally, in the last part, the same samples were analysed in circulation with a multipoint probe. A CCSWA has been applied again and showed that different scattering phenomenon occurred between the categories. Moreover, it highlighted a heterogeneity in the phases' composition that couldn’t be detected in static measurement
Péroumal, Armelle. "Caractérisation des fruits et de la pulpe de six accessions de Mammea americana : Aptitude à la transformation des fruits et caractérisation des composés phénoliques de la pulpe". Thesis, Antilles-Guyane, 2014. http://www.theses.fr/2014AGUY0702/document.
Texto completoOur work focuses on the physical and chemical properties of six mamey apple cultivars in order to select elite cultivars suitable for food processing or as table fruit. The antioxidant activity of the fruit pulp, the identification and quantification of the polyphenols responsible for it, and ultrasound assisted extraction method were also investigated.According to our results, the postharvest routes for every cultivar could be different. Pavé 11, Lézarde and Ti Jacques were found to be good for consumption, giving sweeter fruits with high total phenolic and carotenoid contents. Sonson, pavé 11 and Lézarde had suitable characteristics for the manufacturing of mamey products. The polyphenolic composition of the pulp determined by HPLC-DAD and UPLC-MS showed the presence of phenolic acids, condensed tannins, flavonols and flavanols. The results of the antioxidant test (DPPH and ORAC) point out that the most antioxidant cultivar was Ti Jacques. The design and optimization of the ultrasound assisted extraction method has done for polyphenols extraction. The results showed that the polyphenols rich extract contains the same content of phenolic acids and flavonols in comparison to the conventional method. Additionally, the dry extract obtained with a “green” solvent, had good organoleptic properties
Paccou, Matthieu. "Caractérisation physique et chimique de suspensions concentrées de calcite". Montpellier 2, 2002. http://www.theses.fr/2002MON20190.
Texto completoMartin, Lucile. "Etude de l'oxyde de cuivre CuO, matériau de conversion en film mince pour microbatteries au lithium : caractérisation des processus électrochimiques et chimiques en cyclage". Thesis, Pau, 2013. http://www.theses.fr/2013PAUU3027/document.
Texto completoThe miniaturization of electronic components and the increasing number of their functionalities lead to the development of suitable energy microsources, among which lithium microbatteries appear. Despite the excellent performances of these all-solid-state electrochemical power sources, one main limitation that remains is their surface capacity. Its value being intrinsically connected to the nature of electrode materials, we chose to focus on CuO thin films which are characterized by a theoretical volumetric capacity (426 µAh .cm-2.µm-1) in far larger than the one of conventional intercalation materials used today. Indeed, this material reacts with lithium according to a particular mechanism, referred as conversion reaction, inducing the formation of a multiphase nanostructured system with a high complexity. In the framework of this study, understanding of electrochemical and chemical mechanisms which take place during the cycling of copper oxide thin films (CuO) was the main objective. This one has required a fine characterization of the electrode active material and the generated interfaces (solid/solid interfaces and solid/electrolyte interface). These studies have been mainly carried out with X-ray Photoelectron Spectroscopy (XPS), Atomic Force Microscopy (AFM) and theoretical approaches based on quantum chemistry methods. The chemical and morphological properties of the cycled CuO thin films have been linked to their electrochemical behavior. An important influence of their initial structure and morphology was then evidenced
M'Nassri, Rafik. "Élaboration et Caractérisations physiques des manganites à effet magnetocalorique". Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENY076/document.
Texto completoThe studies presented in this manuscript deal with the synthesis and characterization of ferromagnetic perovskite oxides. Four material systems have been described in this work ( Pr0.6-xEuxSr0.4MnO3 et Pr0.6-xErxSr0.4MnO3 ) et lanthanum ( La0.6Sr0.2Ba0.2-x□xMnO3 et (La0.6Sr0.2Ba0.2MnO3)1-x /(Co2O3)x ) . Our samples have been synthesized using the solid-state reaction method at high temperatures. Rietveld refinement of the X-ray diffraction patterns using Fullprof program shows that all our samples are single phase and crystallize in the distorted structures. Magnetic measurements show that all our samples exhibit a paramagnetic–ferromagnetic transition with decreasing temperature. The Curie Temperature TC shifts to lower values with increasing substitution in the Pr0.6-x(Eu or Er)xMnO3 system and under the effect of barium deficiency in the La0.6Sr0.2Ba0.2-x□xMnO3 system. From the magnetization isotherms at different temperatures, magnetic entropy change ∆Sm and relative cooling power RCP have been evaluated. By means of the connection between the specific heat and the magnetization was determined the variation of the specific heat ΔCp in these samples using the results ΔSm. Our results confirm that the characteristic values of the magnetocaloric effect are very sensitive to the applied magnetic field, where the study of their dependence on magnetic field has a very great interest. For fixed temperatures, the magnetic field dependence of magnetic entropy change ∆Sm is accounted for by the n exponent, which may be derived by a numerical fitting to the formula ∆Sm ~ a (µ0H)n where a is a constant. This study allows one hand, identify materials that behave similarly and ways to improve these properties and it is, on the other hand, a useful tool to extrapolate these properties under conditions not accessible in the laboratory
Laine, Fabien. "Synthèses, caractérisations structurales et propriétés physiques d’oxydes de fer". Caen, 2016. http://www.theses.fr/2016CAEN2018.
Texto completoThis thesis work remains part of a context of research on multiferroic materials which present charge order and concerns the synthesis and physicochemical characterization of iron borates. Among these compounds, the ludwigite Fe2+2Fe3+O2BO3 has sparked particular interest due to its interesting electronic and magnetic properties. Indeed, this oxyborate exhibits a structural transition at TCO = 283 K, and two magnetic transitions are observed, at 112 K and 75 K. We have examined the influence of the cationic substitution in the Fe3-xMnxO2BO3 solid solution (0
Lestournelle, Franck. "CdIn2Te4 matériau électrooptique : cristallogénèse, caractérisations physico-chimiques et optiques". Phd thesis, Université Sciences et Technologies - Bordeaux I, 1990. http://tel.archives-ouvertes.fr/tel-00171602.
Texto completoPapadopoulos, Dimitrios. "Synthèses d'analogues de lécithines : caractérisations physico-chimiques et biologiques". Nancy 1, 1996. http://www.theses.fr/1996NAN10323.
Texto completoGiang, Thi Phuong Ly. "Support immunologique pour biocapteur : caractérisations physico-chimiques et biologiques". Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112184/document.
Texto completoThe aim of my PhD thesis, conducted as part of a collaboration between the laboratory of protein separation sciences and nanotechnology (Paris-Sud Galen Institute) and the Micro and Nano System (basic electronics institute) group was to study the influence of self-assembled monolayers on the biological activity of bioreceptor toward biosensor development. In this project, we choose the organosilanes that can bind covalently to the silicon. Two silanes (7-octenyl trichlorosilane(OTS) and 3- aminopropyltriethoxysilane (APTES)) were studied., Their impact on the stability and the functionality of bio- receptor , model mouse immunoglobulin G (IgG), were evaluated. Spectroscopic characterization by XPS and infra- red Fourier transformed (FTIR) was first carried out to assess that the silanized surface exhibit carboxylic groups. The homogeneity of the surfaces was measured by AFM. Then, IgG were immobilized on these supports, covalently and a topographic AFM study was conducted to measure the distribution of these antibodies. The orientation of the grafted antibody was investigated by immune-enzymatic assays. We have also evaluated the binding capacity of the IgG immobilized on both surfaces. Then, the impact of aging on APTES surface was evaluated by spectroscopics and biological methods
Gaignard, Clément. "Criblage, identification et caractérisations physico-chimiques d'exopolysaccharides de microalgues et Cyanobactéries". Thesis, Université Clermont Auvergne (2017-2020), 2019. http://www.theses.fr/2019CLFAC067.
Texto completoThe main objective of this thesis was to improve knowledge on the capacity of microalgae and Cyanobacteria to produce Exopolysaccharides (EPS). Screening carried out on 166 strains from the Roscoff Culture Collection (RCC) made it possible to identify 45 new potentially EPS producers. Biochemical studies using High Performance Anion Exchange Chromatography with a Pulsed Amperometric Detector (HPAEC-PAD), and Gas Chromatography with Mass Spectrometry (GC/MS) confirmed the polysaccharide nature of 20 new identified polymers. During this work, cultures in 1,4 and 5 L Photobioreactors (PBR) were performed on few strains in order to characterize at best their EPS (biochemical compositions and physicochemical characteristics). This word led, in addition, to the identification of a heteroxylan from the microalga Glossomastix. Its EPS consists of a main chain of β-(1,3)- and β-(1,4)-d-Xylp substituted in O-2 and O-3 positions by various chains and/or terminal residues such as d-Xylp-(1→6)-d-Galp, d-Xylp-(1→4)-d-Galp, d-Xylp-(1→3)-d-Galp, Galp-(1⟶SF-Xylp-(1⟶Xylp-(1⟶Glcp-(1⟶. Finally statistical analyzes carried out on 81 monosaccharide compositions of microalgae EPS made it possible for the first time to establish a link between biochemical composition and phylogenetic membership of microalgae
D'Almeida, Mélanie. "Synthèse et caractérisations physico-chimiques et biologiques de revêtements implantaires bioactifs". Thesis, Lyon 1, 2014. http://www.theses.fr/2014LYO10297/document.
Texto completoIn the past years, population requirement for dental care service increased. More precisely, replacement of missing tooth using dental implant is now a common intervention. As implant provides an artificial root, this procedure is permanent. The failure of the placement procedure is mainly due to an inflammatory disease: peri-implantitis. This disease leads to the death of bone tissues surrounding the dental implant. Today only curative solutions are available, and no implants can prevent bacterial development. It appears that preventing post-surgical complications by designing antibacterial implants is now a public health issue. To achieve this goal, we evaluate in this thesis different solutions to design bioactive implant coatings. We focused our work on coating of a model titanium surface by a bioactive polymer: chitosan. Polymer binding on the substrate is achieved by covalent link using a coupling agent. We described each step of the coating synthesis and characterized its biological properties using both surface chemistry analysis and cell biology techniques. We studied its behavior in an acid environment and analyzed its biological and antibacterial properties in vitro. Results of this work were used to select the bioactive coating with the best properties for the intended application, particularly due to its resistance in acidic condition and its antibacterial activity against common bacteria
Cougnenc, Sylvine. "Caractérisations physique et chimique des flux d'aérosols atmosphériques et marins sur la côte méditerranéenne française". Aix-Marseille 3, 1994. http://www.theses.fr/1994AIX30017.
Texto completoHellio, Serughetti Dominique. "Les gels physiques et chimiques de gelatine : structure et rhéologie". Paris 6, 2004. http://www.theses.fr/2004PA066461.
Texto completoMapemba, Moulakou Elise. "Synthèses, caractérisations structurales et physico-chimiques de fluorures d'éléments tétravalents". Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2007. http://tel.archives-ouvertes.fr/tel-00718104.
Texto completoSurblé, Suzy Nathalie. "Synthèse et caractérisations physico-chimiques de matériaux hybrides poreux multifonctionnels". Versailles-St Quentin en Yvelines, 2006. http://www.theses.fr/2006VERS0046.
Texto completoSynthesis and physico-chem Porous solids are known as being a strategie mate rials class for their potential applications in fields such a~ catalysis, gas separation, storage or optical properties. This work has aimed to synthesize new multifonctionnal porous materials. The first chapter recalls the history of porous solids from zeolithes to today. A short structural description of several hybrid solid with carboxylates has been developed. The following chapters mention two solids, iIIustrating clearly the concept of scale chemistry and they show the contribution of simulation in resolution of structures from X-ray powder data. Porous solids, ca lied MIL88, are flexible and isoreticular. The Amplitude of breathing is unique in the field of porous materials: between 87% and 230%. This amplitude is selective and reversible. Structural determination of hybrid solids with large pores size (MIL 100 and MIL 101) using X-ray powder data is a turning point i our history. These solids are unique with hierarchy of extra-large pore sizes: microporous cage and two mesoporous cages perfectly crystallized. They have a giant cells volumes (380000 A3 et 700000 A3) and a record surface area : 3100 m2. G-1 and 5900 m2. G-1. The two final sections bring up on the one hand, the synthesis of new carboxylate of rare earths and on the other hand a spectroscopie study of the Eu3+ cations in attempt of proposing a correlation between crystalline structure and optical properties. Ical characterization of multifonctionnal porous materials
Boury, Bruno. "Nouveaux précurseurs chimiques de céramiques : synthèses, caractérisations et traitements thermiques". Montpellier 2, 1989. http://www.theses.fr/1989MON20230.
Texto completoEghiaian, Frédéric. "Caractérisations structurales et physico-chimiques de la protéine prion ovine". Paris 6, 2005. http://www.theses.fr/2005PA066134.
Texto completoOthmani-Assmann, Houda. "Caractérisations physico-chimiques et rhéologiques d'argiles tunisiennes en milieux organiques". Paris 11, 2007. http://www.theses.fr/2007PA114816.
Texto completoTwo tunisian clays, interstratified smectite - illite including kaolinite, were the subject of organic treatment by adsorption of various quantities of alkyl ammoniums matter. The intercalation of surfactants in the smectite part of clays leads to several possible arrangements. In our study, these arrangements depend on different parameters such as the number of carbon in the alkyl chain, the amount of intercalated salt, the clay’s cationic exchange capacity and the method of preparation. The kaolinite and illite fractions are not concerned by the intercalation of alkyl ammoniums. The dispersion of prepared organoclays in two organic solvents did not lead to a layers swelling but, on the contrary, to a contraction. The rheological study of organoclays/solvents systems showed that all the studied systems present a plastic behaviour
Martinie, Olivier. "Caractérisation physique et chimique de décharges hors équilibre : application au traitement des NOx". Orléans, 2000. http://www.theses.fr/2000ORLE2047.
Texto completoLemau, de Talancé Vincent. "Synthèse et caractérisation physico-chimique de phospholes électropolymérisables et de chalcogénophospholes". Rennes 1, 2008. http://www.theses.fr/2008REN1S069.
Texto completoThese thesis was dedicated to the synthesis of pi-conjugated systems owning phospholes, for opto-electronic applications. The first chapter deals with the synthesis of phospholes owning 3,4-(ethylenedioxy)thienyl groups. Their physico-chemical properties (UV/Visible, fluorescence, electrochemistry) and electropolymerisation are also described. Finally, the reactivity of polymers incorporating sigma-3,lambda-3 phosphole subunits are discussed. The second chapter deals with the synthesis of a heteroelement-linked biphosphole. The synthesis of dioxophosphole anhydrides and aminophospholes has been studied. A study of the reactivity and of the physical properties of the intermediates : 1-bromophosphole and 1-cyanophosphole has been made. The last chapter deals with the synthesis of 1-hydroxyoxophospholes, and her coordination chemistry. During the synthesis of these compounds, some intermediates have been synthesised and their physical properties have been studied
Lesage, Julien. "Nouveaux Phosphates d'Elément Trivalent : Synthèses, Déterminations Structurales et Caractérisations physico-chimiques". Phd thesis, Université de Caen, 2006. http://tel.archives-ouvertes.fr/tel-00187612.
Texto completoLesage, Julien. "Nouveaux phosphates d’élément trivalent : synthèses, déterminations structurales et caractérisations physico-chimiques". Caen, 2006. http://www.theses.fr/2006CAEN2062.
Texto completoThis thesis deals with the study of mixed framework phosphates whose structures contain cavities or sheets which are able to host cations in insertion. These materials can be used in numerous fields, in catalysis for example. We studied more particularly A M P O systems in which A = NH4, Rb, Cs, Ba or Sr and M = Ga, In or Al. We have isolated nineteen new phases by low temperature hydrothermal synthesis and high temperature solid state synthesis, in air or sealed tube. Structural determinations have been performed by single crystals X Ray diffraction, systematically combined with powder X Ray diffraction studies and EDX analysis, and sometimes completed by electron diffraction in a TEM, infrared spectroscopy and thermogravimetric analysis. We have also tested the activity of one of these phases in selective catalytic reduction of nitrogen oxides, by mass spectroscopy and in situ and operando IR spectroscopy. The precise determination of the crystalline structures of these new phases (two of them are original) allowed us to confirm the great structural diversity of this class of compounds. Moreover, the analysis of theirs characteristics and their comparison with similar phosphates highlighted the relationships existing between the way of synthesis used, the chemical composition studied and the structures obtained. All this results led us to conceive a simple method to order those structures depending on their opening level
Deabate, Stefano. "Caractérisations physico-chimiques et électrochimiques d'hydroxydes de nickel synthétisés par électrodialyse". Montpellier 2, 2001. http://www.theses.fr/2001MON20137.
Texto completoMonchau-Godbille, Francine. "Elaboration et caractérisations physico-chimiques et biologiques de biocéramiques utilisées comme substituts osseux". Lille 2, 2001. http://www.theses.fr/2001LIL2MT07.
Texto completoBoinsk, Frédéric Romuald. "Analyse et caractérisation d'une silice soumise à un processus de dégradation chimique : approche ponctuelle et locale". Mulhouse, 2007. https://www.learning-center.uha.fr/opac/resource/analyse-et-caracterisation-dune-silice-soumise-a-un-processus-de-degradation-chimique-approche-ponct/BUS4081234.
Texto completoThese works are based on the study of the structural behaviour of a heterogeneous reactive silica resulting from a natural siliceous aggregate (flint) submitted to a physico-chemical degradation process: the Alkali Silica Reaction. The impact of the reaction on the aggregate depends punctually of the degree of heterogeneousness of the structure; therefore, the appeal to the techniques of punctual analysis is then necessary. So, all the stages of the degradation of the silica on a grain of some microns were realized due to the use of the microbeam of the line LUCIA on SLS. The study of the behaviour of elements calcium and potassium in the structure of the aggregate was realized by EDX and consolidated by the analysis of the atomic environments of the silicon and cations by the interpretation of X-Ray absorption spectrums (XANES). These studies allowed to advance in the understanding of reactions mechanisms involved during ASR
Habinshuti, J. "Du nanocristal de PbSe à l'hétéro-nanostructure PbSe/CdSe : synthèse chimique et caractérisation des propriétés physiques". Phd thesis, Université des Sciences et Technologie de Lille - Lille I, 2011. http://tel.archives-ouvertes.fr/tel-00687960.
Texto completoHabinshuti, Justin. "Du nanocristal de PbSe à l’hétéro-nanostructure PbSe/CdSe : synthèse chimique et caractérisation des propriétés physiques". Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10012/document.
Texto completoThe tunability of electronic and optical properties of semiconductor nanocrystal (NC) is an important matter in nanotechnology because of their multiple potential applications in optoelectronics such as solar cells, nanotransistors, light emitters, biological markers…Core/shell QDs which are heterogeneous NCs have attracted increasing attention over the past decade, especially because of their enhanced photoluminescence properties and the possibility to create spatially separated excitons by means of a staggered core/shell band alignment. We studied lead chalcogenide NCs because of their unique physical properties which are very different from those of their corresponding bulk materials. Their high dielectric constant (ε∞=23 for PbSe) and the small effective masses of their electron and hole, create excitons with a relatively large effective Bohr radii. These properties lead to a strong confinement of the charge carriers and phonons., thus making them them promising building blocks for a wide number of applications. In the first part of this work, PbSe and PbSe/CdSe NCs with a narrow size distribution and high structural quality have been synthesized, using a colloidal route. Characterizations have been performed using several techniques (electron microscopy, X-ray diffraction (XRD), electron diffraction (SAED), photoemission (XPS/UPS), Raman and absorption spectroscopic measurements).By using deposition techniques such as Langmuir-Blodgett deposition, homogenous, compact thin films of PbSe and PbSe/CdSe NCs have been fabricated. UPS/XPS measurements performed with synchrotron radiations give the valence band offset between the core and the shell of these core/shell NCs
Gilbert, Laura. "Caractérisation physico-chimique et sensorielle d'ingrédients cosmétiques : Une approche méthodologique". Phd thesis, Université du Havre, 2012. http://tel.archives-ouvertes.fr/tel-00956601.
Texto completoAvat, Florence. "Contribution à l'étude des traitements thermiques du bois jusqu'à 300°C : Transformations chimiques et caractérisations physico-chimiques". Phd thesis, Ecole Nationale Supérieure des Mines de Paris, 1993. http://tel.archives-ouvertes.fr/tel-00831249.
Texto completoAdam, Laure. "Synthèse, caractérisations structurales et physico-chimiques de nouveaux phosphates d'éléments de transition". Caen, 2009. http://www.theses.fr/2009CAEN2057.
Texto completoThis thesis deals with the study of transition element phosphates, whose mixed frameworks contain cavities able to host cations. The great structural wealth in this family of compounds opens the way to numerous properties. We have chosen to study A-M-P-O(-H) systems in which A is a monovalent cation and M is a transition element (mixed-valent if possible) or post transition element, in order to obtain new materials for catalytic applications. In this context, the study of the A-M-P-O(-H) systems, with A = NH4, Li, Na, K, Rb, Cs and M = Fe, Mn and In has been undertaken. The other aim of this work was a better understanding of the influence of synthesis experimental conditions on the nature of the obtained phases. In spite of the difficulty to synthesize new materials in the considered systems, eleven new phases have been isolated and three of them exhibit original framework. Structural determinations have been performed by single crystal X-ray diffraction combined with powder X-ray diffraction and EDX analysis. The study of catalytic properties for DeNOx reaction via the NH3-SCR have been carried out by “in situ” and “operando” spectroscopy and mass spectroscopy for one iron phosphate. Magnetic properties of four compounds, which are reported in this manuscript, are discussed
Ameur, Sami. "Caractérisations de membranes chimiques et biologiques par mesure d'impédance : Application à l'immunodétection". Ecully, Ecole centrale de Lyon, 1998. http://www.theses.fr/1998ECDL0034.
Texto completoEl, Kalamouni Chaker. "Caractérisations chimiques et biologiques d’extraits de plantes aromatiques oubliées de Midi-Pyrénées". Thesis, Toulouse, INPT, 2010. http://www.theses.fr/2010INPT0068/document.
Texto completoMidi-Pyrenees region has a rich and unvalorized wild vegetal heritage, especially for aromatic plants. In the framework of the search for new natural flavorings e.g. WONF, we chose to adopt the way of valorization of the medieval aromatic plants of this region, because they have been always picked in a wild state without being ever grown. In a first step, a global bibliographical survey study based on historical books, library archived documents and computerized data banks, was made in order to identify regional plants which were used by our ancestors for their odorous, culinary or medicinal activities. We selected five aromatic plants, e.g. Achillea millefolium, Calamintha grandiflora, Tanacetum balsamita, Myrrhis odorata and Monarda didyma. In a second step, physico-chemical, sensory and biological studies of volatiles and non volatiles fractions, obtained by extractions of the selected medieval plants were carried out, to judge their aromatic, antioxidant and antibacterial activities and their interest within the framework of new european regulations. Theses results show a significant odorous, antioxidant and antimicrobial activities for all selected plants. In a third step, such plants were rare or their harvesting problematic, inducing a limited sampling. We decided to investigate two strategic approaches to perform a rapid evaluation of native essential oil, based either on a classic sampling with a specific/ultra sensitive detection such as Comprehensive GC, nor the use of a specific/high effective sampling system with a classic detection. This last methodology was based on a self designed apparatus “Crushing Finger Device” (CFD), allowing to copy the crushing of leaves between fingers and to trap the volatiles emitted to their later chromatographic analysis. Finally, in the aim to expand the use of aromatic plants, also to enlarge the assortment of oil products, a pre-industrial application were carried out. Infusion of plants and flavoring of vegetable oil by essential oil were studied. During processing of aromatized vegetable oil, volatiles from added aromatic plants or essential oil migrate to oil to give a specific aroma and a significant biological activity. Plantes aromatiques oubliées, Huile essentielle, Antioxydant, Antibactérien, Simulateur de froissement, Composés d’arômes, Achillea millefolium, Calamintha grandiflora, Tanacetum balsamita, Myrrhis odorata, Monarda didyma