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Hydrometallurgie --- Chlorure --- Nitrate --- Hydrolyse --- Oxydation --- Hydrometallurgie --- Chlorure --- Nitrate --- Hydrolyse --- Oxydation
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Hydrométallurgie --- Hydrométallurgie --- Fer --- Hydrolyse
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Chimie physique et théorique --- Fer --- Chimie physique et théorique --- Fer --- Hydrolyse
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Poly(vinylamine) (PVAm) is involved in a broad range of applications due to its interesting properties including complexation of metallic ions and polyelectrolytes, pH responsiveness, adhesion to surfaces, etc. It is currently prepared by hydrolysis of poly(N-vinylamide)s synthesized by conventional radical polymerization. Although controlling the molecular parameters of PVAm could be useful to finely adjust its properties, it remains challenging. In this work, we developed the controlled homopolymerization of N-vinylacetamide (NVA) via organometallic-mediated radical polymerization (OMRP) in the presence of cobalt complexes. The controlled copolymerization of NVA and vinyl acetate (VAc) was then studied leading to unique well-defined statistical copolymers. In order to have a precise idea of the structure of these copolymers, we determined the comonomers reactivity ratios. The synthesis of block copolymers was also explored. Eventually, the hydrolysis of these NVA/VAc-containing copolymers was optimized giving access to unprecedented poly(vinylamine) and poly(vinylalcohol)-based copolymers.
poly(vinylamine) --- OMRP --- polymérisation radicalaire --- Copolymères --- hydrolyse --- rapport de réactivité --- Physique, chimie, mathématiques & sciences de la terre > Chimie
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Hydroxyapatite, a calcium phosphate that is the main constituent of bone, is extensively synthesized and shaped to produce synthetic bone and dental prostheses. Among the available methods of forming ceramics, 3D stereolithography printing offers the following advantages: creation of customizable free forms (customized bone implants), high precision, good surface finish and excellent mechanical properties of produced ceramic parts. Typically, the stereolithography consists in solidifying a photosensitive plastic resin layer by layer with UV radiation. To print ceramic parts, for instance with hydroxyapatite, a ceramic powder is incorporated in the photosensitive resin and then the resulting mixture is printed. The ceramic final part is obtained after a heat treatment to break down the organic components of the printed part. However, many aspects of stereolithography ceramic printing still need to be developed. The work done in this memory allowed to control the printing process step by step: from the synthesis of the raw material (hydroxyapatite) to the final ceramic pieces after heat treatment. The main objective was to develop an innovative hydroxyapatite synthesis route to produce a powder with the same characteristics as a commercial powder currently used for ceramic stereolithography printing. This goal achieved, ceramic pieces could be printed with a desktop 3D printer from the synthesized powder L’hydroxyapatite, un phosphate de calcium qui est le principal constituant des os, est largement synthétisé et mis en forme pour produire des prothèses osseuses et dentaires synthétiques. Parmi les méthodes de mise en forme de céramiques disponibles, l’impression 3D par stéréolithographie offre les avantages suivants : la création de formes libres personnalisables (implants osseux sur mesures), une grande précision, une bonne finition de surface et d’excellentes propriétés mécaniques des pièces céramiques produites. Typiquement, la stéréolithographie consiste à solidifier une résine plastique photosensible, couche par couche, grâce à un rayonnement UV. Pour imprimer des pièces céramiques, d’hydroxyapatite par exemple, il suffit d’incorporer une poudre céramique dans la résine photosensible, puis d’imprimer le mélange obtenu. La pièce finale est obtenue après un traitement thermique pour décomposer les composants organiques de la pièce imprimée. Cependant, de nombreux aspects de l’impression de céramique par stéréolithographie doivent encore être développés. Le travail accompli dans ce mémoire a permis de contrôler chaque étape du processus d’impression : de la synthèse de la matière première (hydroxyapatite) à l’obtention de pièces céramiques après traitement thermique. L’objectif principal était de pouvoir développer une voie de synthèse innovante d’hydroxyapatite permettant de produire une poudre répondant aux mêmes caractéristiques qu’une poudre commerciale actuellement utilisée pour l'impression céramique par stéréolithographie. Cet objectif atteint, des pièces céramiques ont pu être imprimées avec une imprimante 3D de bureau à partir de la poudre synthétisée.
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Cellulose is a major constituent of papers made from plant fibers and combustible component of non-food energy crops. An ideal reference for scientists in natural and synthetic polymer research, this book applies basic biology as well as polymer and sugar chemistry to the study of cellulose. It provides key requirements for understanding the complex structure and biosynthesis of cellulose and its dissolution into new solvents. Cellulose Science and Technology also clarifies the enzymatic hydrolysis of cellulose leading to simple sugars that can be fermented into bioethanol. It examines the bac
Cellulose. --- Cellulose --- Chemistry --- Chimie --- Technologie --- technology --- Biosynthèse --- Biosynthesis --- Structure chimique --- chemical structure --- Propriété physicochimique --- chemicophysical properties --- Hydrolyse enzymatique --- Enzymatic hydrolysis --- Dégradation --- degradation --- Produit cellulosique --- Cellulose products --- Biocarburant --- Biofuels --- degradation. --- Chemistry. --- CELLULOSE --- CHEMISTRY
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Pesticide --- pesticides --- Élimination des déchets --- Waste disposal --- Impact sur l'environnement --- Environmental impact --- Biodégradation --- Biodegradation --- Hydrolyse --- Hydrolysis --- Conditionnement --- Packaging --- Réglementation --- Regulations --- Technologie --- technology --- USA --- Pesticides --- Pesticide waste --- Civil & Environmental Engineering --- Engineering & Applied Sciences --- Environmental Engineering --- Environmental aspects --- Management --- Law and legislation --- Containers --- United States --- Pesticides - Environmental aspects. --- Pesticides - Containers. --- Pesticides - Law and legislation - United States. --- Biodegradation. --- Dechet de pesticide --- Degradation photochimique
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Rhizopus oligosporus --- Fermentation --- État physique --- physical states --- Protéine --- proteins --- Hydrolyse --- Hydrolysis --- Soja --- Soybeans --- Digestibilité --- Digestibility --- 664.8.039.7 --- 664.849 --- Preservation by biological processes. Preservation by fermentation --- Vegetable pastes, pureés --- Theses --- 664.8.039.7 Preservation by biological processes. Preservation by fermentation --- Soybeans. --- Ssf
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Tomate --- Tomatoes --- Produit à base de légume --- Vegetable products --- Hydrolyse --- Hydrolysis --- Activité enzymatique --- Enzyme activity --- Pectine --- Pectins --- Propriété rhéologique --- Rheological properties --- Propriété organoleptique --- Organoleptic properties --- Propriété physicochimique --- chemicophysical properties --- Aptitude à la conservation --- Keeping quality --- 664.849 --- 663.813 --- Vegetable pastes, pureés --- Natural fruit and vegetable juices --- Theses --- 663.813 Natural fruit and vegetable juices --- Tomatoes.
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Glycérol --- Glycerol --- Acide gras --- Fatty acids --- Hydrolyse --- Hydrolysis --- Activité enzymatique --- Enzyme activity --- Émulsion --- Emulsions --- Séparation --- Separating --- Membrane --- membranes --- Filtration --- Bioréacteur --- Bioreactors --- 66.093.8 --- 664.3 --- Edible oils and fats. Margarine. Protein foodstuffs --- Theses --- 664.3 Edible oils and fats. Margarine. Protein foodstuffs --- 66.093.8 Hydrolysis --- Glycerol. --- Emulsions. --- Separating.
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