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Dubs, Patrice. "Etude d'un jet d'azote supercritique utilisé dans un prototype industriel de traitement de surface à faible impact environnemental". Electronic Thesis or Diss., Nancy 1, 2010. http://www.theses.fr/2010NAN10121.
Pełny tekst źródłaA new and efficient process of surface treatment is developed and exists in prototype form at present. The process aims at injecting an inert gas, such as nitrogen, at supercritical conditions through a nozzle. The jet resulting from the expansion of the fluid at high pressure and supercritical temperature impinges normally a flat surface. Alternatively to water jet technologies, which need expansive purification of water after use, and to other classical surface treatment process, this process provides environmental (no generation of additional waste), technical (action on the coating) and energetical (efficiency) benefits. However, the physical phenomena involved in the jet are still poorly understood at present. To understand and model these phenomena, numerical analysis is presented. This analysis is part of a study strategy that aims at gradually increasing the complexity of modeling. A first model aims at describing the evolution of the fluid in time and space, assuming a compressible axisymmetric viscous flow. In this model, the fluid is assumed perfect. A direct extension of this model is then presented where real fluid effects are taken into account in the compressible flow. These models are implemented in finite volume CFD code. Test cases are studied to validate the numerical models. A study of industrial-type configurations, representative of the conditions of use of the process of surface treatment by nitrogen is then conducted
Hommel, Thierry. "Environnement et stratégies des firmes industrielles : le modèle de la gestion anticipative de la contestabilité appliqué à la production des OGM agricoles et à l'industrie du traitement de surface en France et en Allemagne". Paris, EHESS, 2001. http://www.theses.fr/2001EHES0053.
Pełny tekst źródłaRaymond, Gaëlle. "Réduction des impacts environnementaux des ateliers de traitement de surface : application de stratégies de production plus propre et plus sûre". Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2009. http://tel.archives-ouvertes.fr/tel-00786001.
Pełny tekst źródłaDubs, Patrice. "Etude d'un jet d'azote supercritique utilisé dans un prototype industriel de traitement de surface à faible impact environnemental". Thesis, Nancy 1, 2010. http://www.theses.fr/2010NAN10121/document.
Pełny tekst źródłaA new and efficient process of surface treatment is developed and exists in prototype form at present. The process aims at injecting an inert gas, such as nitrogen, at supercritical conditions through a nozzle. The jet resulting from the expansion of the fluid at high pressure and supercritical temperature impinges normally a flat surface. Alternatively to water jet technologies, which need expansive purification of water after use, and to other classical surface treatment process, this process provides environmental (no generation of additional waste), technical (action on the coating) and energetical (efficiency) benefits. However, the physical phenomena involved in the jet are still poorly understood at present. To understand and model these phenomena, numerical analysis is presented. This analysis is part of a study strategy that aims at gradually increasing the complexity of modeling. A first model aims at describing the evolution of the fluid in time and space, assuming a compressible axisymmetric viscous flow. In this model, the fluid is assumed perfect. A direct extension of this model is then presented where real fluid effects are taken into account in the compressible flow. These models are implemented in finite volume CFD code. Test cases are studied to validate the numerical models. A study of industrial-type configurations, representative of the conditions of use of the process of surface treatment by nitrogen is then conducted
Chahboun, Najat. "Compréhension des mécanismes de colmatage des couches anodisées sur alliages d’aluminium aéronautiques et développement de nouvelles formulations de colmatage". Electronic Thesis or Diss., Université de Lorraine, 2015. http://www.theses.fr/2015LORR0318.
Pełny tekst źródłaAluminium alloys are very used in the aircraft industry as structural materials because of their low density and their good mechanical properties. They have a polyphase microstructure that is causing electrochemical discontinuities and increasing sensitivity to corrosion. A system of protective coatings containing chromate Cr(+VI) is traditionally formed at the surface of these alloys. However, the REACH environmental guidelines impose Cr(+VI) surface treatments replacement because of chromate carcinogenicity. The aim of the thesis work has been the development of a new surface treatment constituted of a sulfuric acid anodizing (SAA) and a sulfate chromium and fluorozirconate salts sealing (Cr3+/ ZrF62-). The study of the SAA electrochemical process linked the alloys microstructure and the anodic layer porous morphology developed at their surface. The Cr3+ / ZrF62- sealing treatment is realized by a simple immersion of the anodized alloy in the solution. It is demonstrated that the sealing is caused by a local alkalinization of the anodized coating surface that leads to the precipitation of the Cr3+ and ZrF62- salts. These ones are forming a sealing film of about 300 nm thick, very covering of the nanometric pores. The anodic layers sealing greatly improves the corrosion resistance of the anodized alloys by forming an additional barrier against corrosive agents and by healing the corrosion initiation. The developed treatment allows both to achieve Cr(+VI) treatments performance over a wide range of alloys and to satisfy the environmental requirements
Charles, Jérémie. "Procédés physico-chimiques de décontamination et impact des rejets aqueux de la filière traitement de surface : approches chimique et écotoxicologique". Thesis, Besançon, 2012. http://www.theses.fr/2012BESA2040.
Pełny tekst źródłaThe surface treatment (ST) industry is currently undergoing major upheavals, particularly concerning environmental aspects, due to increasingly stringent standards. ST uses large volumes of water and chemicals in its manufacturing processes and its wastewater is acknowledged as being among the most polluting. The main environmental problem facing ST plants is the high pollution load of the effluent they generate. In this thesis, we analyzed and optimized three physicochemical units for the treatment of ST industrial wastewaters. We present the abatements obtained in the levels of pollution after the various chemical optimizations validated in the laboratory and then transposed to the industrial site. To evaluate the utility of each optimization proposal, bioassays using three bioindicators (Daphnia magna, Gammarus pulex, Lactuca sativa) were also carried out on the effluents of the treatment plants. The results showed that discharge waters were characterized by a polycontamination, organic and metallic, highly variable in time. These effluents also presented a high toxicity towards the bioindicators studied. Bioassays confirmed the preponderant role of metal in the toxicity. The optimization of the station and chemical treatment proposed reduced the organic load and the concentrations of metals. Decreasing pollutant concentrations in the wastewaters led to a significant reduction of their toxicity on the three bioindicators. This demonstrates that there is a relationship between “chemical efficiency” and “reduction of environmental impact”
Saulais, Muriel. "Colonisation végétale des basins d'infiltration et de rétention : caractérisation de la flore et évolution des caractéristiques physico-chimiques de l'horizon de surface végétalisé". Phd thesis, INSA de Lyon, 2011. http://tel.archives-ouvertes.fr/tel-00715802.
Pełny tekst źródłaCoetsier, Clémence. "Approche intégrée de la gestion environnementale Des produits pharmaceutiques dans des rejets de Stations d'épuration urbaines et leur milieu récepteur : occurrence, impact et traitements tertiaires d'élimination". Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2009. http://tel.archives-ouvertes.fr/tel-00625971.
Pełny tekst źródłaCoetsier, Clémence. "Approche intégrée de la gestion environnementale des produits pharmaceutiques dans des rejets de stations d’épuration urbaines et leur milieu récepteur : occurrence, impact et traitements tertiaires d'élimination". Montpellier 2, 2009. http://www.theses.fr/2009MON20105.
Pełny tekst źródłaPharmaceutical products (PPs), widely consumed by population and discharged in the environment through wastewater treatment process (WTP), are sources of aquatic ecosystems contamination. Environmental risk assessment for these substances involves the accurate quantification of their concentrations and the evaluation of their toxicity for exposed species. Our study dealing with a dozen of representative pharmaceutical compounds was conducted in Southeast France. A LC-MS/MS detection method was developed and a sampling campaign was carried out on 7 urban WTP and the natural waters where they discharge (rivers of the Gard and pond) in order to assess PPs contamination level. Toxicity of PPs was estimated using bioluminescent and growth inhibition tests (Microtox, ToxScreen and Protoxkit). Experiments were conducted to evaluate UV photolysis and activated carbon adsorption capacities for the removal of these compounds. Measurements for samples collected highlight the occurrence of PPs in WTP effluent of Southeast region at concentrations ranging from 10 to 1000 ng. L-1 and reaching hundreds of ng. L-1 in the downstream surface waters. Comparison between the level of exposure and experimental toxicity values completed by literature data suggests that only 3 compounds (propranolol, ibuprofen and diclofénac) may induce a low risk at a local scale (rivers of Gard). Complementary treatments of the STP effluents by UV photolysis and activated carbon adsorption prove to be efficient to remove most of the 12 studied PPs and should be considered to reduce the presence and the impact of pharmaceutical products in the environment
Leveillard, Florine. "Méthodologie de minimisation de la pollution appliquée au traitement de surface : étude de l’entraînement comme vecteur de pollution". Thesis, Saint-Etienne, EMSE, 2011. http://www.theses.fr/2011EMSE0598/document.
Pełny tekst źródłaCurrently, via the prevention principle, environmental regulations incite industries to implement strategies to reduce the pollution at the source (ICPE, IPPC, IED). Industries are sometimes lost in front of various proposed technical solutions. The application of cleaner production strategies such as good operational procedures and good practices of management allow to answer these constraints.The metal finishing activity uses a lot of water and chemicals and thus generates polluted effluents. The objective of this work is to propose a simple methodology of limitation of the pollution flows and of the water specific consumption of metal finishing workshops.Then, experimental studies have allowed, on one hand, to create an easy method of the drag-out calculation and, on the other hand, to show and to quantify the influence of different parameters on the drag-out, from a qualitative and quantitative point of view. They are, for example, the shape and the roughness of the treated pieces, the draining time, the superficial tension of the treatment solutions but also the stirring type and duration of rinsing.All these elements, integrated into the methodology of pollution minimization, allow to realize a diagnosis of the process line. Moreover, it permits to estimate the impact of a modification of this installation on the specific consumption of water, on the pollution balance assessment and on the rinsing quality. So, this methodology can help to optimize and to limit consumptions of water and chemicals not only on the process line but also in wastewater treatment plant, so decreasing the environmental impacts and the running costs
Grosdidier, Samuel. "Détection de cibles en milieu maritime par radar HF à ondes de surface". Brest, 2010. http://www.theses.fr/2010BRES2048.
Pełny tekst źródłaHigh Frequency Surface Wave (HFSW) radars (3-30MHz) provide largely better ranges than classical costal systems used for sea monitoring. HFSW radars make possible to get range further than line of sight and to monitor continuously and cheaply a large area of sea. But for different reason it is hard to process the received signal: a low spatial and temporal resolution and a strong tendency to be polluted by different kind of interferences and noises. The general topic of this PhD thesis is to deal with a very noisy signal for detection purpose. The first work deals with the development of a methodology to generate images obtained by HSWR radars (Range-Doppler images). This tool was developed taking into account most of the system parameters and leads to control entries parameters for the sea (wave height, wave directions. . . ), the radar (central frequency, bandwidth. . J, and target characteristics (radar cross section, range, velocity. . . ). For the detection task, from generated and real data, a source separation techniques called Morphological Component Analysis (MCA), initially proposed by Starck et al. 2005, is considered. The goal is to extract an image made of the target signature, the decision part being solved by using a common constant false alarm rate method. The selected methodology in this thesis in order to solve the detection problem by HFSW radars combines modeling and simulation aspects, and real data use
Saulais, Muriel. "Colonisation végétale des basins d’infiltration et de rétention : caractérisation de la flore et évolution des caractéristiques physico-chimiques de l’horizon de surface végétalisé". Thesis, Lyon, INSA, 2011. http://www.theses.fr/2011ISAL0116/document.
Pełny tekst źródłaUrban stormwater basins surfaces can be highly contaminated and can be spontaneously or intentionaly vegetated. The aim of this work is to better characterize the role of the vegetation on heavy metal (Zn, Cd, Cu) mobility. Firstly, vegetation inventory has pointed out the high species diversity in these devices (from ruderal vegetation to wetland plants). Then, a physico-chemical characterization of surface samples vegetated by dominant species has been carried out. We have shown that carbonates and organic matter play a major role in the control of heavy metal mobility. The parameters which are the most spatially and temporally variable are essentially related to organic matter cycle (nitrate, heavy metal fraction bound to organic matter), and to the introduction of stormwater suspended matter (heavy metals, texture). At the maximum of plant growth phase, heavy metal mobility is enhanced and the period of plant death leads to a better heavy metal retention in the basin surface. This thesis invites us to consider plants as agents of surface stormwater basin transformation and to include plants in future research work
Seghini, Maria Carolina. "Mechanical Analysis and Fibre/Matrix Interface Optimization for Next Generation of Basalt-Plant Fibre Hybrid Composites". Electronic Thesis or Diss., Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2020. http://www.theses.fr/2020ESMA0003.
Pełny tekst źródłaGlobal awareness of environmental issues has resulted in the emergence of “green” composites, in which natural fibres are used to replace synthetic ones. However, in semi-or structural applications, it can be inconvenient to use composites based on natural fibres. A possible solution to this problem is the development of hybrid composite materials, combining together plies of natural and synthetic fibres. In this framework, the aim of this research project was to develop basalt-flax fibre hybrid composites with a view to obtaining more environmentally friendly composites for semi-structural applications. Hybrid composites were produced through vacuum infusion molding with epoxy matrix.For comparison purposes, 100% flax fibre composites and 100% basalt fibre composites were also manufactured. A quasi-static and dynamic mechanical characterization showed that the hybridization allows the production of a composite with intermediate mechanical performances compared to those possessed by flax and basalt composites. However, the damage analysis has revealed the need to optimize the fibre/matrix interface adhesion quality, in order to increase the mechanical properties of the resulting hybrid composites. For this reason, different surface modification treatments have been specifically designed and investigated for flax and basalt fibres. Flax and basalt fibres were treated by the physical process of Plasma Enhanced Chemical Vapor Deposition. Flax fibres were also subjected to two chemical treatments using enzymatic species and supercritical CO2. The effects of the surface modification treatments on the thermal stability, morphology and mechanical properties of flax and basalt fibres have been investigated. The degree and extent of fibre/matrix adhesion were analyzed by micromechanical fragmentation tests on monofilament composites. The adhesion quality between fibres and both epoxy and vinylester matrices has been assessed in terms of critical fragment length, debonding length and interfacial shear strength. High-resolution μ-CT has been used to support the analysis of the damage mechanisms during fragmentation tests. For both flax and basalt fibres, the best results were obtained after the plasma polymer deposition process. This process was able to produce a homogeneous tetravinylsilane coating on the surface of basalt and flax fibres, which resulted in a significant increase in the fibre/matrix adhesion, thus paving the way for the next generation of more environmentally friendly hybrid composites for semi-structural applications
Fiche, Anthony. "Distributions alpha-stable pour la caractérisation de phénomènes aléatoires observés par des capteurs placés dans un environnement maritime". Phd thesis, Université de Bretagne occidentale - Brest, 2012. http://tel.archives-ouvertes.fr/tel-00835073.
Pełny tekst źródłaPicasso, Marco. "Simulation numérique des traitements de surface par laser /". [S.l.] : [s.n.], 1992. http://library.epfl.ch/theses/?nr=1011.
Pełny tekst źródłaGallitelli, Donato. "Traitements de surface mécaniques : modélisation et caractérisations expérimentales". Thesis, Troyes, 2018. http://www.theses.fr/2018TROY0013.
Pełny tekst źródłaMechanical surface treatments are widely used in manufacturing industries in order to improve mechanical properties of materials. Among them, shot peening is certainly the most known, even if ultrasonic shot peening and laser shock peening are becoming more and more common. This work consists in a large study of shot peening, divided in three parts.The first one is focused on the conception of a semi analytical model for residual stress prediction after conventional shot peening or ultrasonic shot peening. An approach able to chain the whole shot peening process, starting from process parameters to residual stress field in a structure is proposed. Several numerical simulations of shot-body impacts are carried out in order to determine the parameters of the model.In the second part of this work, a characterization of the ultrasonic shot peening process is performed thanks to many experimental measurements and shot dynamic simulations.The last part of this PhD work corresponds to an experimental analysis focused on the combination of ultrasonic shot peeing with gas nitriding on a martensitic steel. A comparison between ultrasonic shot peening, conventional shot peeing and laser shock peening effects is finally proposed
Aubert, Maelle. "Caractérisation de l'état de surface des sols nus agricoles par imagerie radar TerraSAR-X". Phd thesis, AgroParisTech, 2012. http://tel.archives-ouvertes.fr/tel-00764268.
Pełny tekst źródłaConte, Philippe. "Les traitements de surface des prothèses de hanche sans ciment". Toulouse 3, 1994. http://www.theses.fr/1994TOU31570.
Pełny tekst źródłaBOURGES, CORINNE. "Traitements de surface des polymeres : consequences en mouillage et collage". Paris, ENMP, 1995. http://www.theses.fr/1995ENMP0548.
Pełny tekst źródłaViez, Céline. "Traitements de surface d'alliages d'aluminium : dépôts d'AIN par pulvérisation réactive magnétron". Toulouse 3, 2004. http://www.theses.fr/2004TOU30272.
Pełny tekst źródłaBecause of their poor tribological properties, aluminum alloys can't be used in a lot of applications. To meet interesting properties, surface treatments are widely used. In this study, AlN coatings were prepared by reactive magnetron sputtering from Al target. OES and thickness of the coatings are used to analyse the influence of the different parameters on growth rate. The sputter yield and the growth rate increase with the increase of the power. First, the deposition rate increases with the pressure, but due to an amount of collisions, it decreases with an increase of pressure. The N2 concentration in the discharge has a drastic effect on the deposition rate. When the N2 concentration increases, the deposition rate strongly decreases. This is a result of the nitriding of the target. But, if the N2 concentration is too low the AlN films are not stoichiometric. A substrate bias of -30V optimize the growth rate. To perform the adhesion of the coatings, different plasma pre-treatments have been made
Thiault, Georges-André. "Problématiques et réflexions éthiques face aux traitements de substitution aux opiacés". Paris 5, 1998. http://www.theses.fr/1998PA05NO83.
Pełny tekst źródłaBoulif, Rachid. "Potentialité d'hydrogénation de l'acier lors de traitements de galvanisation". Châtenay-Malabry, Ecole centrale de Paris, 1993. http://www.theses.fr/1993ECAP0280.
Pełny tekst źródłaSamih, Youssef. "Thermomechanical surface treatments of austenitic stainless steels and their effects on subsequent nitriding during “Duplex” treatments". Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0100/document.
Pełny tekst źródłaOptimizing the surface microstructure and properties is very important to obtain high performance behaviour. Applying appropriate mechanical and thermochemical treatments has been the prime objective of metallurgists. More recently, and particularly for the stainless steels, the Plasma Nitriding was found to be an efficient technique for enhancing the hardness and wear resistance. However, as the nitriding temperature is about 500 °C, the formation of nitrides on the surface leads to a decrease of the corrosion resistance of these alloys. Recent works have shown that using a mechanical pre-treatment allows to decrease the treatment temperature and duration, and also to enhance the nitrogen diffusion within the stainless steels surfaces. In the present work, performances of different Duplex treatments (mechanical + thermochemical) are studied. The Surface Mechanical Attrition Treatment (SMAT), cold rolling and the High Current Pulsed Electron Beam (HCPEB) are used as surface activators prior to plasma nitriding of stainless steels. Before studying the effect of surface activation on the nitrogen diffusion, the effect of the different SMAT parameters (balls size, balls nature, treatment duration … etc.) on the microstructure is analysed. A new technique based on the notion of Geometrically Necessary Dislocations (GND) is used to depict the thickness of the different SMAT-induced layers and compare the effect of the processing parameters. Then, comparative analysis of the results obtained after nitriding of mechanically deformed samples leads to quantify the effect of the different Duplex treatments. X-Ray Diffraction, Secondary Electron Microscopy associated with Electron BackScattered Diffraction (EBSD), hardness measurement and chemical composition analysis by Glow Discharge Optical Emission Spectroscopy (GD-OES) showed the importance of the surface microstructure and deformation state on the nitrogen diffusion
Ramboarina, René. "Influence de l'adsorption sur l'adhésion métallique : cas du système vapeur d'eau-aluminium". Vandoeuvre-les-Nancy, INPL, 1990. http://www.theses.fr/1990INPL032N.
Pełny tekst źródłaZhang, Ga. "Etudes des procédés d'élaboration et des propriétés des revêtements de PEEK et de ses composites". Besançon, 2005. http://www.theses.fr/2005BESA2060.
Pełny tekst źródłaIn recent years, driven by economic and ecologic reasons, thermoplastic coatings have been very attractive for industrial applications. The PEEK (polyetheretherketone) is a polymer with excellent mechanic properties, in particular a good tribological performance. Its tribological behaviour, especially wear resistance properties, can be improved when it is reinforced by the micro-fillers in forms of particles or fibres. Some previous studies show that the pure PEEK coating exhibits good mechanical properties. However, homogenizing the reinforcements in PEEK matrix seems very difficult in the elaboration process. Therefore, it's difficult to obtain a homogeneous PEEK based composite coating using the conventional coating methods. The objective of this work is thus to realize PEEK based coatings (pure and composite) with good mechanical performances. With regard to this aim, four following directs of work have been carried out. Firstly, a new method for the elaboration of PEEK based coatings was developed using screen printing technique. Secondly, the crystallization behaviour of amorphous PEEK coating was studied and this crystallization behaviour was correlated with coating mechanical properties. Thirdly, the frictional performances of PEEK based coatings were examined; the frictional mechanism was discussed. Finally, a study on the feasibility of densifying by laser the PEEK based coatings was performed
Zou, Jianxin Dong Chuang Grosdidier Thierry. "Mécanismes fondamentaux du traitement de surfaces par bombardements électroniques pulsés application aux matériaux métalliques et intermétalliques /". [S.l.] : [s.n.], 2007. ftp://ftp.scd.univ-metz.fr/pub/Theses/2007/Zou.Jianxim.SMZ0718.pdf.
Pełny tekst źródłaBahri, Hanane. "Études des traitements de surface des nanopoudres de verre en milieux cimentaires". Mémoire, Université de Sherbrooke, 2015. http://hdl.handle.net/11143/7558.
Pełny tekst źródłaWierre, Christophe. "Optimisation des traitements de surface non réactifs pour la forge à froid". Valenciennes, 1996. https://ged.uphf.fr/nuxeo/site/esupversions/e4d28904-bb12-46e0-becc-c1a11b73b6f4.
Pełny tekst źródłaLagain, Philippe. "Contibution expérimentale aux traitements de surface par laser avec apport de poudres". Aix-Marseille 2, 1989. http://www.theses.fr/1989AIX22063.
Pełny tekst źródłaJurczak, Julien. "Produit dose-surface pour la radiothérapie : application aux protocoles de traitements stéréotaxiques". Thesis, université Paris-Saclay, 2022. http://www.theses.fr/2022UPASP025.
Pełny tekst źródłaEvolution of radiotherapy techniques, in particular with the advent of stereotactic treatments, led to an increased use of small radiation beams allowing a better dose conformation to the volume while sparing the surrounding normal tissues. As a consequence, clinical conditions are significantly different from the reference conditions in terms of absorbed dose in water at a point, as described in international protocols. The loss of traceability thus observed leads to an increased uncertainty of the dose delivered to the patient. In order to overcome the difficulties of absorbed dose traceability in small fields, the Laboratoire National Henri Becquerel (LNHB) suggests an innovative approach. Instead of considering a point measurement, an integrated measurement over an area larger than the irradiation field was adopted through another quantity: the Dose Area Product (DAP). This thesis presents the establishment of primary standards in terms of Dose Area Product in water (DAPw) for square and circular field sizes less than or equal to 15 mm side or diameter. In order to transfer these new dosimetric standards to users, three plane-parallel ionization chambers with the same sensitive area than the large graphite calorimeter of the LNHB were constructed and calibrated against the newly established primary standards, with a standard uncertainty on the calibration coefficient of less than 0.7% (k=1). For field sizes between 5 mm and 15 mm, the three chambers show the same behavior, with a calibration coefficient that is independent of the field shape on the one hand and that increases slightly, about 1.7% on average, with the field size on the other hand. These promising results pave the way for a paradigm shift in small field dosimetry.In order to progress towards the clinical use of DAP, in particular through the measurement of field output correction factors (OF), a comparison was made between the classical approach of point measurement corrected by the factors provided by the IAEA TRS 483 protocol, and the absorbed dose at a point deduced from the DAP thanks to the knowledge of the two-dimensional mapping of the beam, which is accessible with radiochromic films. In that way, a new optical instrument dedicated to radiochromic films reading, compatible with a metrological application, was also developed in this thesis. Once adopted, this new approach would improve the parameterization of the treatment planning system (TPS), which is an essential link in the radiotherapy treatment chain
Leroy, Loïc. "Influence de traitements de surface sur le comportement du Nickel en EDMA". La Rochelle, 2003. http://www.theses.fr/2003LAROS105.
Pełny tekst źródłaIn order to increase the corrosion resistance of Ni in artificial seawater, various surface treatments from more classical (thermomechanical treatments) to more sophisticated (ion implantation, electron irradiation, ion beam assisted deposition) have been performed. Many experimental techniques have been used, and impedance spectroscopy is shown to allow a detailled study giving the specific frequency for each step of the corrosion process. A model is proposed accounting for the experimental results. Two main stages are detected with increasing immersion time. The first, corresponding to the passivation of the surface is quick and protective; the second, at longer immersion times, is due to a slow degradation of the passive film induced by the Cl- ions
Sanchez, Manuel. "Traitements de surface de fibres de carbone, effets sur l'adhésion carbone-époxyde". Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb376010505.
Pełny tekst źródłaJones, Alistair. "Co-located collaboration in interactive spaces for preliminary design". Phd thesis, Université de Technologie de Compiègne, 2013. http://tel.archives-ouvertes.fr/tel-01067774.
Pełny tekst źródłaChorel, Marine. "Étude des traitements multicouches utilisés dans un environnement à faible hygrométrie sur les installations laser de puissance". Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0188/document.
Pełny tekst źródłaThe chirped pulse amplification demonstrated in 1985 allowed the development of petawatt class laser such as Petal (Petawatt Aquitaine Laser). The increase of power of those facilities is limited by the resistance to laser-induced damage of the optical components placed after the compression stage. The aim of this thesis is to improve the laser-induced damage threshold of those components which are multilayer dielectric mirrors. Three paths of improvement are considered the change of design (number of layer, thicknesses), of materials and/or deposition process. A numerical study allows evaluating the potential improvement brought by two of those paths. This led to the development of a design optimization algorithm that required the prior characterization materials. Consequently, various materials deposited as single layers were laser damage tested and optically characterized to evaluate the adequacy of the materials with the deposition process. The results show a wide discrepancy that cannot be explained by the laws exposed in the literature. However, a good correlation was found between the intrinsic laser-induced damage thresholds in the infrared with the absorption in the ultraviolet confirming the influence of the multiphoton absorption in the laser-induced damage mechanisms. Finally, those experimental results combined with the optimization algorithm allowed the development of mirror samples that exhibit laser-induced damage threshold 73% higher than one of classical mirrors
Rueda, Fulgencio. "Caractérisation et propriétés superficielles de latérites vénézuéliennes soumises à différents traitements". Lille 1, 1997. http://www.theses.fr/1997LIL10179.
Pełny tekst źródłaHami-Eddine, Mostafa. "Etude de l'activation de surface des polyoléfines par flammage". Mulhouse, 1994. http://www.theses.fr/1994MULH0328.
Pełny tekst źródłaHaulon, Stéphan. "Endoprothéses couvertes de l'aorte abdominale : fuites de type II et traitements de surface". Lille 2, 2002. http://www.theses.fr/2002LIL2MT04.
Pełny tekst źródłaWu, Hong Ming. "Traitements de surface de matériaux carbonés en vue de la réalisation de microcapteurs". Ecully, Ecole centrale de Lyon, 1994. http://www.theses.fr/1994ECDL0041.
Pełny tekst źródłaKanoufi, Frédéric. "Reduction de la liaison carbone - fluor : application aux traitements de surface du polytetrafluoroethylene". Paris 7, 1998. http://www.theses.fr/1998PA077235.
Pełny tekst źródłaMouls, Benjamin. "Étude et développement de nouveaux traitements de surface sur alliage de magnésium Elektron 21". Toulouse 3, 2014. http://thesesups.ups-tlse.fr/3812/.
Pełny tekst źródłaThe main purpose of this thesis was to achieve new protective coatings on Mg alloy without using any CMR compounds. This study was thus focused on the impregnation of conversion layers to enhance the corrosion resistance of Elektron 21 (EV31A) magnesium alloy, available as two kinds of substrates (EL21T6 and EL21T5) exhibiting different microstructures. This study was split in two parts: - understanding and control of the etching mechanisms occurring in nitric acid solution to get reliable parameters to achieve reproducible coatings. - preparation in acidic media of porous anodic films for their further impregnation with nanoparticles using electrophoresis. The first part of this study was devoted to the study of the influence of different experimental parameters (such as the acid concentration, the temperature and stirring speed) on the etching rate in nitric acid solution. Finally, it turned out that a bath temperature of 25°C, a HNO3 concentration of 1,2mol/L and stirring speed of 250rpm were the best experimental conditions to achieve reproducible etching rate, whatever was the etching bath lifetime. Moreover, values of the corresponding kinetic parameters (kinetic rate constants, free energy, activation energy) were obtained for the first time from an in depth thermodynamic and kinetic analysis. The purpose of the second part of this study was to prepare porous anodic films using phosphoric acid solution, often used for standard Mg chemical conversion treatments. Here the goal was then to accurately control the formation of the phosphate layer by an electrochemical process. Using weight change measurements and ICP analysis, it was especially demonstrated that the influence of the electrical polarization was promoted at the lowest concentration (0. 01mol/L) of phosphoric acid. Also, a higher temperature (75°C instead of 25°C) of the electrolytic bath increased the stability of Mg phosphate layer. EDX and XRD analysis showed then that the resulting coating was made for a part by amorphous compounds and for another one by crystallized phases, especially newberyte (MgHPO4,3H2O). Besides, from SEM observations it was noticed that the achievement of conversion layers electrochemically controlled enabled to obtain thicker layers than the chemical conversion layers, prepared in similar bath conditions. However, these anodic films showed a high porosity, due to numerous microcracks. Eventually, this study was focused on the electrophoretic impregnation of the previous conversion layers and the optimization of operating parameters (voltage, duration) allowed to successfully fill the cracks with silica nanoparticles. Nevertheless, it came out from a SIE study of these coatings that further improvements would be achieved using inhibitor grafted particles to enhance the corrosion resistance
Cherigui, Mohamed. "Réalisation par projection thermique de revêtements amorphes et nanocristallins destinés au blindage magnétique". Besançon, 2005. http://www.theses.fr/2005BESA2009.
Pełny tekst źródłaThe aim of this work is to study the iron based amorphous and nanostructured coatings having exceptional magnetic properties elaborated by thermal spray process. The elaboration of a coating with such process requires the comprehension of possible correlations existing between the thermal spraying parameters, the magnetic properties and the structural characteristics of deposits. A feasibility study of the amorphous and nanostructured deposits was made in a first time using the atmospheric plasma spray process (APS). In a second time, a ferromagnetic nanocrystalline deposits were elaborate from the mechanical alloying powders using high-velocity oxy-fuel process (HVOF). The coatings realised showed a good stability of the magnetic properties after heat treatments at high temperatures
Chahboun, Najat. "Compréhension des mécanismes de colmatage des couches anodisées sur alliages d’aluminium aéronautiques et développement de nouvelles formulations de colmatage". Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0318.
Pełny tekst źródłaAluminium alloys are very used in the aircraft industry as structural materials because of their low density and their good mechanical properties. They have a polyphase microstructure that is causing electrochemical discontinuities and increasing sensitivity to corrosion. A system of protective coatings containing chromate Cr(+VI) is traditionally formed at the surface of these alloys. However, the REACH environmental guidelines impose Cr(+VI) surface treatments replacement because of chromate carcinogenicity. The aim of the thesis work has been the development of a new surface treatment constituted of a sulfuric acid anodizing (SAA) and a sulfate chromium and fluorozirconate salts sealing (Cr3+/ ZrF62-). The study of the SAA electrochemical process linked the alloys microstructure and the anodic layer porous morphology developed at their surface. The Cr3+ / ZrF62- sealing treatment is realized by a simple immersion of the anodized alloy in the solution. It is demonstrated that the sealing is caused by a local alkalinization of the anodized coating surface that leads to the precipitation of the Cr3+ and ZrF62- salts. These ones are forming a sealing film of about 300 nm thick, very covering of the nanometric pores. The anodic layers sealing greatly improves the corrosion resistance of the anodized alloys by forming an additional barrier against corrosive agents and by healing the corrosion initiation. The developed treatment allows both to achieve Cr(+VI) treatments performance over a wide range of alloys and to satisfy the environmental requirements
Wang, Weidong. "Modification et caractérisation de la surface du noir de carbone". Mulhouse, 1992. http://www.theses.fr/1992MULH0251.
Pełny tekst źródłaStarck, Patrick. "Etude du frottement et du transfert commençants du polyéthylène haute densité (PEhd)". Mulhouse, 1986. http://www.theses.fr/1986MULH0002.
Pełny tekst źródłaGallet, Didier. "Traitements de surface d'Inp et contribution à l'optimisation des interfaces de reprises d'épitaxie InP()/InP(p) réalisées par GSMBE". Ecully, Ecole centrale de Lyon, 1992. http://www.theses.fr/1992ECDL0048.
Pełny tekst źródłaBriend, Guillaume. "Développement d'un nouveau procédé de nettoyage chimique humide pour les surfaces front end des technologies CMOS (45 nm et au-delà) intégrant de nouveaux matériaux". Grenoble INPG, 2009. http://www.theses.fr/2009INPG0015.
Pełny tekst źródłaIn microelectronics, the course of miniuaturization imposes the introduction of metal and dielectrics layers in CMOS transistors to improve electrical yields. However, this integration involves a total review of process (thermal treatment, etch, wet steps. . . ). This work particularly focus on Front End cleans steps around the gate. Challenges are following : first, there must remove more and more all types of contamination with minimum materials consumption and without damages on sensitive structures. On the other hand, the process must be chemical compatibility with new materials. There also must be integrated in a new configuration tool (single wafer instead of batch tool). Thus, they must be involved to give best performances. It's why, today, provide an Advanced clean process for CMOS sub-45nm technology node is a real challenge
Deforet, Maxime. "Croissance et densification d'un épithélium en géométrie confinée". Paris 6, 2012. http://www.theses.fr/2012PA066490.
Pełny tekst źródłaEpithelium consists of closely packed cells that make up the inside or outside lining of body’s surfaces. We study the growth of an epithelium in a confined geometry. Using microfabrication techniques, we developed a surface treatment protocol allowing tissue confinement inside an adhesive area over a few weeks. The technique achieves a micrometer resolution and any geometry of the adhesive area is feasible. In our study, the size is such that cells behave collectively. We analyse the growth of epithelium with Madine Derby Canine (MDCK) cells in circular adhesive regions. Migration and densification of the tissue are studied with PIV (Particle Image Velocimetry) and others image analysis techniques. We characterize velocity field and observe large amplitude oscillations of the velocity, whose period match the hypothesis of stress wave propagating through the epithelium. We also characterize the appearance of a tridimensionnal rim of cells at the periphery of the epithelium, similar to the first step of tubulogenesis. In two other experiments, using opposite geometry, we study how the epithelium can cover an anti-adhesive region. We show the covering requires a supracellular actomyosine cable, and the cable tension balanced by a surface tension defines a critical size beyond which the anti-adhesive region cannot be covered by the epithelium
Ji, Gang. "Elaboration et caractérisation de revêtements nanocristallins Fe-40AI préparés par projection thermique". Besançon, 2003. http://www.theses.fr/2003BESA2034.
Pełny tekst źródłaNanostructured Fe-40Al coatings were prepared by High Velocity Oxy-Fuel (HVOF) spraying from milled powder. The as-sprayed coatings as well as the milled powder were examined by X-Ray Diffraction, Scanning Electron Microscopy, Transmission Electron Microscopy, Differential Scanning Calorimetry and Mössbauer Spectroscopy to improve the understanding of structure formation in such coatings; in particular, to clarify the origin of the nanostructures. The relationships among the process parameters, the microstructure and the coating properties (hardness and corrosion) were also investigated by the variation of the size of the feedstock powder. The resultants indicate that the coatings show a bimodal structure where 3D nanograins, resulted from a partial crystallization of the starting powder, can be essentially conserved in non melted particles. Alternatively, because of the rapid solidification, the 2D nanograins can be formed in fully melted particles. Finally, the hardness/corrosion balance can be optimized by a good selection of powder size feedstock
Bennes, Jonathan. "Etude, réalisation et caractérisation de microsystèmes pour la manipulation de liquides". Besançon, 2006. http://www.theses.fr/2006BESA2085.
Pełny tekst źródłaThe handling of droplets by using acoustic methods is the main topic of this work. The devices, which have been previously developed in the laboratory, allow toggle droplets displacement in one dimension for volume between 5 to 100 [micron]). Nevertheless, " lab on chip " applications re- quire two dimensions displacement for 1 to 5 [micron]) droplets volume. Consequently, an ultrasonic transducer based on acoustic amplifier has been developed. This device allows two dimensions displacement of the liquid on a thin polymer shrink-warp, avoiding cross contamination of successive samples. Moreover, only one vibration mode (piston mode) is used which makes easier the electronic drive. During this work, Raleigh device's allowing two dimensions displacement of liquid has been also studied. Former Works allowed displacement and detection of liquid. However, many problems such as droplet's guiding or surface treatment appeared. New design for the transducers has been developed which en able to entrap acoustically the liquid between two Raleigh waves. The surface treatment of neobate lithium wafer has been achieved by grafting a super hydrophobic self assembled monolayer. The contact angle of these edifices is closed to 140 and the stability is higher than two months
Bretez, Michel. "Rôle du silicium et de l'aluminium dans la réaction fer-zinc : application à la galvanisation des aciers". Lille 1, 1986. http://www.theses.fr/1986LIL10156.
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