Dissertations / Theses on the topic 'Réduction du CO'
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Villagra, Angel Eduardo. "Photo-dissociation de l'eau et photo-réduction du CO₂ assistées par co-catalyse moléculaire." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS282/document.
The main objective of this research work was to put into evidence the co-catalytic effect of organo-metallic molecular complexes containing transition metals as reactive centers, adsorbed at the surface of doped semiconductors with photo-activity with regard to water photo-dissociation and carbon dioxide photo-reduction, in view of practical applications in photochemistry and photo-electrochemistry. First, appropriate materials (two photoactive semiconductors and two molecular co-catalysts) have been identified and selected (results are presented in chapter I). Then, we have designed, constructed and optimized a specific test bench that can be used for the continuous detection and titration of reaction products (results are presented in chapter II). Product analysis was achieved by coupling a gas-phase chromatograph to the photo-electrochemical reactor. Then, photoactive semiconductors and molecular co-catalysts have been elaborated/synthesized and their intrinsic properties have been measured (results are presented in chapter III). Finally, the co-catalytic activity of molecular complexes has been put into evidence and several performance indicators such as reaction kinetics and turn-over frequency have been measured (results are presented in chapter IV)
Malfoy, Philippe. "Réduction catalytique de NO et N2O par H2, CO ou C3H8." Lille 1, 1997. http://www.theses.fr/1997LIL10183.
Gotico, Philipp. "Stratégies bio-inspirées pour la réduction catalytique et la valorisation du dioxyde de carbone." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS283/document.
The criticality of global warming urges for the advancement of science to reduce carbon dioxide (CO₂) emissions in the atmosphere. At the heart of this challenge is the development of sustainable catalysts that can help capture, activate, reduce, and eventually valorize CO₂. This PhD work tried to respond to this call by developing molecular mimics inspired by natural systems in the larger scheme of artificial photosynthesis. Firstly, it involved tracking the journey of a photon of visible light and how it is transformed to a reducing power able to reduce CO₂. Secondly, in search for more efficient and stable catalysts, new mimics were synthesized inspired by the exceptional performance of CO dehydrogenase enzymes (CODH) in reducing CO₂. Lastly, further understanding of CODH also led to a proof-of-concept that directly valorizes the photo-produced CO for the synthesis of isotopically-labelled amide bonds, a common motif in pharmaceutically-relevant drugs
Duong, Hong Phong. "Highly selective electrocatalysts for carbon monoxide conversion to multi-carbon products." Electronic Thesis or Diss., Sorbonne université, 2023. http://www.theses.fr/2023SORUS467.
Carbon dioxide (CO2) valorization by electrolysis has shown its potential as an environmentally friendly and efficient method to synthesize value-added products like hydrocarbons and alcohols. However, the detrimental issue associated with carbonation in alkaline electrolyte limited the possibility to scale up CO2 electrolysis. Lately, a two-step concept, in which CO2 was firstly reduced into carbon monoxide (CO) with an industrially relevant Faradaic efficiency (FE) of 90% by a solid oxide electrochemical cell, then CO would be subsequently electrochemically reduced into ethylene with a high FE of 60% has been realized. As a result, there has recently been great attention focused on finding selective heterogeneous electrocatalysts to reduce CO into essential multi-carbon products. In this thesis, several copper-based electrocatalysts exhibiting high activity for CO conversion into ethylene, n-propanol and ethanol will be presented. The first chapter focuses on an original dendritic copper catalyst showing excellent selectivity for ethylene production from CO electrochemical reduction. The system exhibited the record FE for ethylene of 78% at an applied current density of 100 mA cm-2 with a record half-cell energy efficiency of 40.5%. In the second chapter, our attempt was focused on developing a nitride-derived silver- doped copper (CuAgN) electrocatalyst showing a high selectivity for CO electroreduction to n-propanol at the optimized condition (FE = 45%, an applied current density of 150 mA cm-2). In comparison with the bare copper nanoparticles, copper nitride and silver-doped copper nanoparticles, the CuAgN material possessed much higher electrochemically active surface area and CO conversion selectivity for n-propanol. Interestingly, the selectivity for C2+ liquid products of CuAgN was largely dependent on the concentration of KOH electrolyte. By employing in-situ characterization and computational modelling, a mechanism for n-propanol production was proposed as the presence of Ag could promote C1-C2 coupling reactions on the CuAg catalyst surface. Finally, according to the literature, C1-C2 coupling reactions were proposed as the key of C3+ products formation, thus the presence of a C2 substrate like acetaldehyde was presumed to boost C3+ products formation. The third chapter demonstrates the effect of an ab initio addition of acetaldehyde as a C2 substrate to CO electrolysis on the selectivity of the CuAgN, D-Cu catalysts, and commercial copper or silver nanoparticles
Bikrani, Mohammed. "Quelques applications des complexes (n(6)-arène)Cr(CO)3 en synthèse électrochimique." Dijon, 1986. http://www.theses.fr/1986DIJOS019.
Guillet, Jérôme. "Etude et réduction d'ordre de modèles linéraires structurés : application à la dynamique du véhicule." Phd thesis, Université de Haute Alsace - Mulhouse, 2011. http://tel.archives-ouvertes.fr/tel-00807199.
Bazzi, Sakna. "Electrogenerated divalent samarium for CO₂ activation : applications in carboxylic acid synthesis." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS397.
CO₂ activation is considered one of the most attractive tools to convert this cheap, abundant and non-toxic gas into valuable chemical feedstocks such as carboxylic acids. The market value of these compounds is expecting a significant increase in the next few years, thus the urgent need for sustainable and eco-friendly production pathways. Divalent samarium complexes are known for their strong monoelectronic reductive power that made them the perfect choice for the reduction of some challenging functional groups. Indeed, in the literature, this reagent has been used in combination with CO₂ but only to achieve the reductive disproportionation of CO₂ while no example reported C-C bond formation via CO₂ activation using the Sm(II) complexes. Herein, we report the CO₂ activation initiated by electrogenerated divalent samarium. Taking advantage of our recently developed method for the in situ generation of Sm(II) species, the synthesis of benzoic acid derivatives was successfully achieved. Furthermore, electrocatalytic CO₂ activation conditions were established in this work and applied not only for the preparation of phenylacetic acids from benzyl chloride derivatives but also for the regioselective hydrocarboxylation of styrene and phenylacetylene analogs. This electrochemical Sm(II)-based protocol offers the next generation of sustainable system to transform CO₂ into highly valued molecules under mild conditions and without the addition of co-reductants
Baati, Khaled. "Stratégie de réduction des cycles thermiques pour systèmes temps-réel multiprocesseurs sur puce." Phd thesis, Université Nice Sophia Antipolis, 2013. http://tel.archives-ouvertes.fr/tel-00947611.
Désilets, Christian. "Développement de nouveaux matériaux et d'outils électroanalytiques pour l'étude de la réduction électrochimique du CO[indice inférieur 2]." Mémoire, Université de Sherbrooke, 2011. http://savoirs.usherbrooke.ca/handle/11143/4895.
Gibilaro, Mathieu. "Co-réduction électrochimique de l'aluminium et des lanthanides en milieu fluorures fondus : application au traitement pyrochimique des effluents nucléaires." Toulouse 3, 2008. http://thesesups.ups-tlse.fr/407/.
Nuclear reaction produces fission products such as lanthanides; these neutrophage elements represent a poison for the nuclear chain reaction and have to be extracted. This thesis concerns lanthanides extraction (neodymium, cerium and samarium) by electrodeposition in the LiF-CaF2 eutectic mixture at 840 °C. The process used is an alloy formation with aluminium by electrochemical co-reduction on an inert tungsten electrode. This technique is based on the simultaneous reduction of Al(III) and Ln(III) ions to obtain an alloy at the cathode. A decrease of the lanthanide activity in the alloy is obtained due to Al-Ln formation and a shift of lanthanide reduction potential to more positive values is observed: the theoretical extraction efficiency is then approaching 100 %. When both Ln(III) and Al(III) ions are present in the molten salt, new reduction waves appear between Al and Ln pure metal depositions and are attributed to Al-Ln alloy formation by co-reduction. The alloy compositions have been characterised in function of electrolysis potential: the more the electrolysis potential is negative, higher is the Ln content in the alloy. Finally, extractions by potentiostatic electrolyses have been carried out and the extraction efficiencies for the different lanthanides are higher than 99. 4 %
Janati, Idrissi Fouad. "Hydrogénation du citral sur des catalyseurs bimétalliques à base de nickel préparés par co-réduction avec le naphtalène-sodium." Grenoble 1, 1992. http://www.theses.fr/1992GRE10012.
Aloisi, Alicia. "Synthèse de nouveaux ligands tripodes et de leurs complexes de coordination pour l’activation de petites molécules." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS360/document.
The extensive use of fossile fuel is currently causing climate change. Anthropogenic emissions of CO₂ enhance the greenhouse effect, resulting in global warming. In order to mitigate this climate change, the share of renewable energy is increasing and hydrogen seems to be a good candidate to stock energy to compensate the seasonal variations of those energies. One way to store H₂ is the hydrogenation of CO₂ to synthesise liquid molecules as formic acid and methanol. Those liquids can be conveyed in an easier way. In case of a lack of energy, H₂ can be recovered through dehydrogenation of those molecules thinks to catalysts. In this thesis, we studied the synthesis of organometallic complexes able to activate those small molecules, thus, growing a fundamental knowledge. As a number of triphos-metal complexes are known to catalyse hydrogenation and dehydrogenation reactions, we focused on the elaboration of ligands alike. With those ligands in hand, several non-noble metal based complexes (Fe (II), Co (II) and Cu (I)) were synthesized, which are active in CO₂ hydroboration catalysis. A complex of ruthenium(II)was grafted on silica through one of this ligand, in order to recycle it when it used as a catalyst. On the second hand, we designed a new ligand which could favor metal-ligand cooperativity. H₂ was succesfully activated with a copper(I) complex coordinated by this ligand, demonstrating that cooperation of the ligand. Finally, the first known cobalt complex active in dehydrogenation of formic acid was synthesised
Fredon, Emmanuel. "Obtention de films plastiques hydrophobes à partir de polysaccharides contenus dans des co-produits agricoles." Toulouse 3, 2001. http://www.theses.fr/2001TOU30199.
Trillat, Jean-Frédéric. "Réduction de NO par CO sur catalyseurs bimétalliques Pd-Mn : application à la conversion de mélanges complexes en post-combustion automobile (moteurs à essence)." Lyon 1, 1997. http://www.theses.fr/1997LYO10029.
Lacroix, Olivier. "CO₂ capture using immobilized carbonic anhydrase in Robinson-Mahoney basket and packed absorption column reactors." Master's thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25183/25183.pdf.
Arnaud, Sylvain. "Purification et caractérisation de l'oxydase terminale de la bactérie marine Pseudomonas nautica 617 : propriétés d'oxydo-réduction vis-à-vis de 02 , CO et n-alcanes." Aix-Marseille 2, 1990. http://www.theses.fr/1990AIX22054.
Filimonenkov, Ivan. "Electrocatalyse de la réduction de l’oxygène et de l’oxydation de l’eau par des oxydes de métaux de transition : cas des pérovskites de Mn et Co." Thesis, Strasbourg, 2019. http://www.theses.fr/2019STRAF072.
A study of electrocatalysis of oxygen reduction (ORR) and oxygen evolution (OER) reactions is closely related with a development of cathodic and anodic materials for fuel cells and elec-trolyzers. An objective of this thesis is to develop and investigate Mn, Co-oxide-based elec-trode materials active and stable in both the ORR and OER. Relationships between electro-chemical characteristics of perovskite/carbon compositions and properties of their compo-nents are stated and experimentally substantiated in the thesis. It is found a corrosion re-sistance of carbon materials under OER conditions is influenced not only by their crystalline order, but also by their intrinsic OER activity. It is shown the ORR and OER activity of Mn, Co-based perovskites linearly depends on the number of rechargeable Mn and Co cations, respectively. It is revealed a reversible oxygen intercalation through a crystal structure of Co-based perovskites occurs under OER conditions as well as at lower potentials
Chupin, Cédric. "Réduction sélective du monoxyde d'azote par le méthane en présence d'oxygène sur Co-ZSM-5 et Fe-ZSM-5 : optimisation des catalyseurs, étude mécanistique et cinétique de la réaction." Lyon 1, 2001. http://www.theses.fr/2001LYO10236.
Décultot, Marie. "Intensification par pervaporation de la synthèse de carbonates organiques à partir d'alcools et de CO₂ Solubility of CO₂ in methanol, ethanol, 1,2-propanediol and glycerol from 283.15 K to 373.15 K and up to 6.0 MPa Organic carbonates synthesis improved by pervaporation for CO₂ utilisation." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMIR08.
CO₂ valorisation consists of using this greenhouse gas that is the most emitted into the atmosphere to produce molecules that are usually synthesized from oil. The combination of CO2 and alcohols produces organic carbonates with many applications. The equilibrium constants of the DEC (diethyl carbonate) and PC (propylene carbonate) synthesis reactions were experimentally evaluated for different operating conditions. A kinetic modelling was carried out based on mechanisms developed in the literature. The pervaporation of reaction mixtures models of DEC and PC allows effective dehydration that displaces the balance of the reaction. The experimental study of the reaction/pervaporation coupling made it possible to multiply by 8 the yields obtained without dehydration. According to the modelling, it is possible to significantly increase yields by improving reaction kinetics and pervaporation conditions
Le, Bas Karine. "Préparation de catalyseurs Pd-Cu-SiO2 à partir d'acétylacétonates : réactivité vis à vis de l'hydrogénation du butadiène-1,3 et de la réduction de NO par CO." Lyon 1, 1994. http://www.theses.fr/1994LYO10299.
Lefaucheur, Charles-Élie. "Étude d’un procédé multi-étapes de traitement pyrométallurgique de déchets industriels spéciaux : application aux boues d’hydroxydes métalliques issues du traitement de surface d’aciers inoxydables." Grenoble INPG, 1999. http://www.theses.fr/1999INPG0100.
Riu, Delphine. "Modélisation et commande de systèmes électriques : de leur structure optimale à leurs performances dynamiques." Habilitation à diriger des recherches, Université de Grenoble, 2010. http://tel.archives-ouvertes.fr/tel-00566876.
Tonda-Mikiela, Pradel. "Étude des interfaces des nanocatalyseurs / glucose et enzymes / O2 pour une application biopile." Thesis, Poitiers, 2012. http://www.theses.fr/2012POIT2308/document.
The work developed in this thesis concerns the study of the behavior of redox reactions at the interfaces "nanocatalyst/glucose" and "enzyme/O2" for a hybrid Biofuel Cell. In this framework, a novel synthesis method of based gold and platinum nanoparticles has been achieved. These synthesized nanomaterials were characterized by different physicochemical techniques to determine their size, morphology and their dispersion in Vulcan XC72R used as substrate. The active surface area of each electrode material was determined by cyclic voltammetry and CO stripping. It has been shown that in the bimetallic catalyst gold promotes platinum activity towards the glucose oxidation. The bimetallic composition Au70Pt30 exhibits the better efficiency. The study by spectroelectrochemistry determined that the B-gluconolactone is the primary product of the glucose oxidation which proceeds at low potential by the dehydrogenation of anomeric carbon on platinum. The reduction reaction of O2 was catalyzed by an enzyme, bilirubin oxidase (BOD). Mediated electronic transfer was performed with two redox mediators, ABTS and an Osmium complex (Os). They have been encapsulated with the enzyme in a Nafion® matrix to construct the interfaces: BOD/ABTS/O2 and BOD/Os/O2. The voltammetric study of the mediators in phosphate buffer revealed two quasi-reversible systems with an apparent potential close to the theoretical potential of the T1 BOD center. Although hardly comparable in terms of current density with the Pt nanocatalyst the O2 reduction is a four electron reaction at the cathodes BOD/ABTS and BOD/Os which deliver an electrode potential close to the Nernst one
Ngameni, Emmanuel. "Comportement électrochimique de biporphyrines adsorbées ou en solutions aqueuses acides : Etude du pouvoir catalytique de la biporphyrine de cobalt, CO::(2) FTF4, à l'égard de la réduction de l'oxygène." Brest, 1988. http://www.theses.fr/1988BRES2021.
El, Hamdaoui Abdeslam. "Catalyseurs de post-combustion automobile à base de palladium : influence des ajouts (Ag, Cr, Rh) sur la réactivité du Pd pour la réduction de NO par CO en atmosphère oxydante." Lyon 1, 1992. http://www.theses.fr/1992LYO10282.
Gras, Antoine. "Séquestration du CO₂ associée aux phénomènes de minéralisation passive du carbone dans les résidus miniers du Projet Dumont Nickel (Abitibi-Témiscamingue, Québec, Canada)." Doctoral thesis, Université Laval, 2018. http://hdl.handle.net/20.500.11794/30265.
The implication of anthropogenic carbon dioxide (CO2) emissions in climate change is now widely accepted and solutions are emerging in order to limit the accumulation of CO2. Carbon mineralization, which allows the sequestration of CO2 through carbonate precipitation, stable minerals over geological time scales, is one of the options considered. Among the proposed carbon mineralization pathways, passive carbon mineralization in ultramafic mining residues can potentially lead to developing carbon-neutral mines. However, the impacts on leachate water quality and evolution of sequestration capacity in natural conditions, on medium and large scales, are still poorly documented. RNC Minerals plans to mine a nickel deposit located in the northwestern part of Quebec. The operation at the Dumont Nickel Project (DNP) would produce approximately 1.7 Gt of ultramafic mining residues. Several factors which influence the carbon sequestration capacity of the DNP residues have been studied in the laboratory, at variable CO2 concentrations. In this study, the processes of passive carbon mineralization in the DNP mining residues are described and the atmospheric CO2 sequestration capacity is estimated, at the experimental cell scale, under natural conditions. In order to study the impacts of meteoric weathering of the DNP residues, two experimental cells were built and instrumented. The first cell EC-1, contains the ultramafic waste rock, and the second EC-2, was filled with milling residues (Tailings). The hydrogeological properties and surface area of the residues contained in the two cells are different whereas the mineralogy is similar. The main minerals in the residues are chrysotile, lizardite, brucite, chlorite and magnetite. Between 2011 and 2015, changes in CO2 concentrations, mineralogy, and chemical composition of leachate waters were recorded. Monitoring of CO2 concentrations showed a decrease in CO2 concentration from the surface (~ 390 ppmv) to the bottom of the cells (~ 100 ppmv). At the same time, the carbon content in the weathered residues increased and the mineralogical analyses revealed precipitation of several magnesium carbonates such as hydromagnesite. These observations indicate that passive mineral carbonation of the mining residues is occurring within the experimental cells, for which three potential sources of CO2 can be identified : (1) the atmosphere, (2) the CO2(g) produced from organic matter oxydation, and (3) CO2(g) produced from carbonate dissolution. The isotopic compositions of CO2(g) and newly formed carbonates were measured. Using these isotopic compositions it was possible to demonstrate that dissolution of CO2(g) in interstitial water limits the sequestration capacity and that atmospheric CO2 is the main source of the CO2 sequestered. Despite the differences between the two experimental cells the same processes control CO2 sequestration. A conceptual model of the carbon mineralization reactions, including evolution of the isotopic compositions, is proposed. The leachate water sampled at the bottom of the experimental cells, between May and November since 2011, is characterized by an alkaline pH (~9.5), a high alkalinity (~90 to ~750 mg/L CaCO3) and a high concentration of magnesium (~50 at ~750 mg/L). This composition is consistent with weathering of ultramafic rocks in a system open to CO2. Since 2012, the chemical composition of the leachate water was evolved seasonnaly. These seasonal variations are explained by: (1) recharge and temeprature variations over the year and (2) increased carbonate precipitation between May and July. The seasonal decrease of alkalinity and magnesium concentrations, caused by increased carbonate precipitation, induces undersaturation of carbonate minerals. Therefore carbonate precipitation self-limits carbon sequestration through a negative feed-back loop. Since 2011, an estimated 13 kg of atmospheric CO2 was sequestered in the milling residues from EC-2, which corresponds to a mean rate of 1,4 (+/- 0.3) kgCO2/tonne/year. Using this mean rate, during the mining operation the milling residues will sequester about 21 kt of atmospheric CO2 each year, which will represents one quarter of the 127,700 tonnes of CO2 emitted. Using MIN3P, a numerical model which allow to simulate multi-component and multiphase reactive transport in unsaturated porous media, the carbon mineralization reactions were simulated in 1D at the center of cell EC-2. The data collected during the 4 years of monitoring were used to calibrate the numerical model. However, none of the simulations allowed to reproduce the evolution of the leachate water geochemistry and the CO2 concentrations observed in the experimental cell. Several simplifications of the conceptual model could explain the differences with the observed data.
Dubé, Patrick. "La spectrométrie de masse électrochimique approche analytique puissante pour l'étude, en ligne, de la nature de l'interface électrocatalytique sur des réactions électrochimiques d'intérêt environnemental telles la réduction CO[indice inférieur 2] et l'oxydation de NH[indice inférieur 3]." Thèse, Université de Sherbrooke, 2006. http://savoirs.usherbrooke.ca/handle/11143/5073.
Le, Quang Long. "Nanomatériaux hybrides TiO2/[Ru(bpy)3]2+ associés à [Cr(ttpy)2]3+ ou [Mn(ttpy)(CO)3Br] ou au pyrrole : synthèse, études spectroscopiques et applications pour la conversion de l'énergie solaire." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAV085/document.
This thesis aims to investigate the possibility of using TiO2 nanoparticles (NPs) as a platform to immobilize proximal coordination complexes that can interact with each other by photoinduced electron transfer. We have studied hybrid nanomaterials combining [Ru(bpy)3]2+ (bpy = 2,2'-bipyridine) as a photosensitizer and [Cr(ttpy)2]3+ or [Mn(ttpy)(CO)3Br (ttpy = 4'-(p-tolyl)-2,2':6',2''-terpyridine) as electron acceptors. To immobilize the various complexes on the surface of TiO2, a phosphonic acid functional group was introduced on one of the bipyridines of the [Ru(bpy)3]2+ center and on the terpyridines of the [Cr(ttpy)2]3+ complex. Under visible light, the TiO2/RuII colloid undergoes a photo-induced charge transfer process leading to a long-lived charge separation state (e )TiO2/RuIII, which makes it possible to be engaged in successive oxidation or reduction reactions. In particular, the visible irradiation of the TiO2/RuII colloid in the presence of [Cr(ttpy)2]3+ and triethanolamine (TEOA) as a sacrificial electron donor allows the two-electron reduction of [Cr(ttpy)2]3+. Subsequently, the [Cr(ttpy)2]3+ complex has been immobilized on the TiO2/RuII NPs to form a RuII/TiO2/CrIII assembly in which the photoinduced electron transfer processes were investigated. In order to propose a system for the photocatalytic reduction of CO2, the [Mn(ttpy)(CO)3Br] and [Ru(bpy)3]2+ complexes were co-immobilized on TiO2 NPs following a chemistry on surface approach to form a RuII/TiO2/MnI triad. Under irradiation at 470 nm, this system exhibits excellent selectivity towards HCOOH as the only product of CO2 photoreduction in DMF/TEOA solvent mixture, in the presence of 1-benzyl-1,4-dihydronicotinamide (BNAH) as a sacrificial electron donor. Another hybrid system linking a [Ru(bpy)3]2+ unit to two pyrrole functions and being immobilized on TiO2 has also been synthesized and studied. Under visible light, the transient (e-)TiO2/[Ru-pyr]3+ species induce the polymerization of pyrrole to form a TiO2/poly(Ru-pyr) nanocomposite. The nanocomposite deposited on an electrode generates, in the presence of TEOA, a stable anodic photocurrent of more than 10 μA.cm-2. All the results show that TiO2 NPs can be used to associate different complexes in a close environment by limiting the interactions in the ground state but allow photoinduced electron transfer processes between them. Depending on the redox potentials of the different components, the electron transfer takes place either through the semiconducting NPs or on the surface
Ouahab, Athmane. "Modélisation des consommations d'énergie et des émissions de CO² à long terme appliquée au secteur résidentiel algérien." Thesis, Tours, 2015. http://www.theses.fr/2015TOUR1801/document.
The residential sector in Algeria consumes 25 % of the final energy and emits about 21% of greenhouse gas emissions. However, there is a significant potential of energy saving in this sector. This leads to looking for ways to make the sector of housing more efficient in terms of energy consumption and CO2 emissions. This thesis aims to develop different methods of quantitative analysis dedicated to improving the performance of the résidential sector in 2050. In other words, the objective is to reduce energy consumption and stabilize CO2 emissions. The comparison between France and Algeria should help to clarify the differences in both dynamic structures housing stock as well as in those induced by climate differentials.This research work fits into a prospective approach. It is based on the principles of prospective exercise developed by Jacques Arcade, Michel Godet, and it is influenced by numerous research works (ETHEL, CLIP). It has the ambition to develop a model of bottom-up energy prospective capable of measuring various trajectories of the evolution of energy consumption in the residential sector and resulting emissions by 2050.This model is based on the data of the central scenario of demography and the housing stock of the Algerian National office of Statistics, and on the well-argued assumptions concerning the démographic evolution of households. The continuation of current trends in terms of energy consumption at the approach of 2050 allows us to draw up a reference scenario on which the thesis is based to identify the actions to be implemented to identify possible solutions. Indeed, by basing itself on a set of technological levers, our model can establish voluntaris scenarios in which several trajectories of the evolution of the consumption/emissions pair can be envisaged.Besides the scientific interest of this work, the developement of this model can establish a help tool for the implementation of an energy policy concerning the improvement of the energy efficiency in the sector of housing ; moreover, the scenarios undertaken could constitute a road map for new energy strategies
He, Jin. "Urban Detection From Hyperspectral Images Using Dimension-Reduction Model and Fusion of Multiple Segmentations Based on Stuctural and Textural Features." Thèse, 2013. http://hdl.handle.net/1866/10281.
This master’s thesis presents a new approach to urban area detection and segmentation in hyperspectral images. The proposed method relies on a three-step procedure. First, in order to decrease the computational complexity, an informative three-colour composite image, minimizing as much as possible the loss of information of the spectral content, is computed. To this end, a non-linear dimensionality reduction step, based on two complementary but contradictory criteria of good visualization, namely accuracy and contrast, is achieved for the colour display of each hyperspectral image. In order to discriminate between urban and non-urban areas, the second step consists of extracting some complementary and discriminant features on the resulting (three-band) colour hyperspectral image. To attain this goal, we have extracted a set of features relevant to the description of different aspects of urban areas, which are mainly composed of man-made objects with regular or simple geometrical shapes. We have used simple textural features based on grey-levels, gradient magnitude or grey-level co-occurence matrix statistical parameters combined with structural features based on gradient orientation, and straight segment detection. In order to also reduce the computational complexity and to avoid the so-called “curse of dimensionality” when clustering high-dimensional data, we decided, in the final third step, to classify each individual feature (by a simple K-means clustering procedure) and to combine these multiple low-cost and rough image segmentation results with an efficient fusion model of segmentation maps. The experiments reported in this report demonstrate that the proposed segmentation method is efficient in terms of visual evaluation and performs well compared to existing and automatic detection and segmentation methods of urban areas from hyperspectral images.