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Bendahmane, Mohamed. "Etude du comportement mécanique du bois avec noeuds simulation numérique /". Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37611789b.
Pełny tekst źródłaKebbi-Benkeder, Zineb. "Biodiversité interspécifique et intraspécifique des extractibles nodaux". Electronic Thesis or Diss., Paris, AgroParisTech, 2015. http://www.theses.fr/2015AGPT0072.
Pełny tekst źródłaWood is a renewable material used by man for construction, furniture, paper making, energy, etc. Wood contains extractives of great economic value which belong to various chemical families such as terpenes, flavonoids, tannins, etc. The knots (base of the branch embedded in the trunk) of some tree species are extremely rich in extractives.This study aims at analysing the inter-specific, intra-specific and within-tree variabilities of knotwood extractives to target the richest species, stations and tree parts. For that purpose, the knots of twenty-three species and those of fifteen firs grown under different conditions were extracted using several solvents and analysed. The results confirm the richness of knots compared to heartwood and sapwood for all species. Overall softwood knots contain mainly more extractives than hardwoods. The main compounds identified in softwoods are lignans, stilbenes, flavonoids and terpenes Gallic acid and flavonoids are present in hardwoods. The study of the vertical profile shows that concentrations decrease from the base of the crown to the tree tip. In addition, the results highlight the influence of growth conditions since dominant trees and/or those grown according to dynamic silvicultures are particularly rich in knot extractives. These results allow considering the valorization of wood industries by-products as bioactive molecules resource for various applications
Kebbi-Benkeder, Zineb. "Biodiversité interspécifique et intraspécifique des extractibles nodaux". Thesis, Paris, AgroParisTech, 2015. http://www.theses.fr/2015AGPT0072/document.
Pełny tekst źródłaWood is a renewable material used by man for construction, furniture, paper making, energy, etc. Wood contains extractives of great economic value which belong to various chemical families such as terpenes, flavonoids, tannins, etc. The knots (base of the branch embedded in the trunk) of some tree species are extremely rich in extractives.This study aims at analysing the inter-specific, intra-specific and within-tree variabilities of knotwood extractives to target the richest species, stations and tree parts. For that purpose, the knots of twenty-three species and those of fifteen firs grown under different conditions were extracted using several solvents and analysed. The results confirm the richness of knots compared to heartwood and sapwood for all species. Overall softwood knots contain mainly more extractives than hardwoods. The main compounds identified in softwoods are lignans, stilbenes, flavonoids and terpenes Gallic acid and flavonoids are present in hardwoods. The study of the vertical profile shows that concentrations decrease from the base of the crown to the tree tip. In addition, the results highlight the influence of growth conditions since dominant trees and/or those grown according to dynamic silvicultures are particularly rich in knot extractives. These results allow considering the valorization of wood industries by-products as bioactive molecules resource for various applications
Billard, Antoine. "Pour une valorisation optimisée de la biomasse forestière basée sur une connaissance de la variabilité de la masse volumique dans l’arbre". Electronic Thesis or Diss., Paris, AgroParisTech, 2021. http://www.theses.fr/2021AGPT0019.
Pełny tekst źródłaBasic density is an important physical property of wood as it helps to explain the behaviour of the tree in situ and the wood in use. Currently, the databases containing mean wood basic density are mainly composed of mean stem wood calculated on core samples taken at 1.30 meters. Thus, variations in basic density within the stem, between components and within components are completely ignored. However, these variations can have an important impact on the calculation of wood aboveground biomass. Moreover, as bark and knots are components of the tree rich in extractives, it is important to know the available fraction of these components in order to test the feasibility of an extractives chemistry pathway. This thesis contributes to the ExtraFor_Est project, which aims to characterise and quantify the extractible resource of forests in the Grand Est and Bourgogne-Franche-Comté regions.In this thesis, three softwood and three hardwood species were studied: silver fir, Abies alba Mill., Norway spruce, Picea abies (L.) H. Karst., Douglas fir, Pseudotsuga menziesii (Mirb.) Franco, pedunculate oak, Quercus robur L., sessile oak, Quercus petraea L. and European beech, Fagus sylvatica L. For softwood species, trees were sampled in plots testing contrasting thinning intensities. In the end, only softwood species could be studied during the time of the thesis, but the other data were prepared for the continuation of the project. Four components of the tree were analysed: stem wood, stem bark, knots and branches. An X-ray tomograph was used to obtain the basic density of the components.In a first step, a comparison between the mean basic density of the stem wood measured at 1.30 m and the mean basic density of the studied components was carried out and the impact of the observed difference on the biomass calculation. It was found that the mean stem wood basic density measured at 1.30 m is significantly higher than the mean stem wood basic density for Abies alba and Pseudotsuga menziesii. Knots, branches and bark are mostly denser than stem wood measured at 1.30 m. These differences in basic density between components lead to an underestimation or overestimation of biomass depending on the component and the species studied, the difference being up to more than 40% for knots, for example.In a second step, the variation of basic density with height in the tree was analysed for stem wood. The results show that the direction of variation depends on the species. Two forms of descriptive models were developed for Abies alba and Pseudotsuga menziesii, one taking as input the mean basic density measured at 1.30 m and the other not taking it into account. The relative RMSEs for Abies alba and Pseudotsuga menziesii are 9.9% and 8.1%, respectively, for the model without the mean basic density measured at 1.30 m and 7.6% and 5.9%, respectively, for the model with the mean basic density measured at 1.30 m.Finally, the study of longitudinal and height-dependent variations in the basic density of stem bark, knots and branches was started. For bark, the basic density decreased with height for Abies alba, decreased and then increased for Picea abies and increased and then decreased slightly for Pseudotsuga menziesii. For branches, it was found that basic density decreases rapidly in the first 50 cm from their insertion on the stem and then remains stable until their apex
Chazelas, Jean-Louis. "Caractéristiques physiques et mécaniques locales du bois dans la zone des noeuds". Clermont-Ferrand 2, 1990. http://www.theses.fr/1990CLF21231.
Pełny tekst źródłaMburu, Francis. "Etude et valorisation de différents bois du Kenya". Nancy 1, 2007. http://docnum.univ-lorraine.fr/public/SCD_T_2007_0057_MBURU.pdf.
Pełny tekst źródłaPrunus africana heartwood and sapwood were extracted using different solvents. Extractives were tested against fungi and termites in relation to the natural durability of Prunus africana. These were tested against Coriolus versicolor, Poria placenta, and Aureobasidium pullulans at concentrations. High inhibition was realized and increased with extract concentration. In some instances, fungal growth started after the control Petri dish was fully colonized showing fungistatic effect than fungicidal effect. Extracted and un-extracted wood samples were also tested against termites. When tested against Coriolus versicolor in the laboratory Prunus africana showed high natural durability. Extracted wood showed low resistance against termites while un-extracted was totally resistant. Dichloromethane extract showed the highest inhibition rate compared to water, acetone and toluene/ethanol extracts against fungi and termites. Microscopie analysis indicate the presence of important quantities of extractives deposited in the vessels which are removed after Soxhlet extraction. Spectroscopie and chromatographie analysis were investigated on dichloromethane extract to identify the compounds responsible for biological activities. Grevillea robusta was treated by cheap sap displacement method using Copper Chrome Arsenate (CCA). Results showed adequate penetration and retention for wood use in different hazard areas. Resistance of Greviflea robusta heat-treated samples was evaluated by malt agar block test against six wood rotting fungi a well as against termites in laboratory and field conditions. High durability against fungi and termites was realized after treatment. There was a positive correlation between decay resistance and mass loss due to thermal treatment. FTIR and 13C MAS NMR analysis showed chemical modification of wood components alte heat treatment
Bauer, Rodolphe. "La modélisation du volume des compartiments riches en composés chimiques extractibles (écorce et nœud) dans six essences d'intérêt des régions Grand-Est et Bourgogne Franche-Comté". Electronic Thesis or Diss., Paris, AgroParisTech, 2021. http://www.theses.fr/2021AGPT0025.
Pełny tekst źródłaIn a context of renewal of the chemical industry and the search for new outlets for forestry, extractives are becoming increasingly interesting molecules, both ecologically and financially speaking. In order to evaluate the relevance of these molecules as a new resource for the chemical industry and a potential outlet for forestry, it is necessary to make a preliminary evaluation of the resource. This requires knowledge of the volume of compartments rich in extractable material, particularly bark and knots. The present study therefore focuses on modeling bark and knot volumes. It focuses specifically on two French regions, the Grand Est and the Bourgogne-Franche-Comté, and on six important species, Abies alba, Picea abies, Pseudotsuga menziesii, Quercu robur, Quercus patraea, and Fagus sylvatica.This study is made possible, on one hand, by the use of a large database including numerous measurements of bark thickness made at different heights on the stems of many trees. On the other hand, new samplings have been made to allow X-ray scanning of nodes all along the stem and thus to determine precisely the volume on a computer picture.In order to model the available amount of bark, three types of models were built, models predicting the volume of bark, models predicting the surface area of bark along the stem and models predicting the thickness of bark at 1m30. The former achieved a relative root mean square error (RMSErel) of 16.7% to 27.5% depending on the species.The study of bark area models showed that it was possible to use a model independent of diameter-over-bark but that model using this variable are more accurate. The RMSErel achieved by these bark area models varied between 23 and 38% depending on the species and model considered.This work showed the importance of using the bark thickness at 1m30 as an input data. As it is rarely measured today, it was also modelled using the DBH. This allowed us to show the influence of altitude on bark thickness at 1.30 m for three species: Abies alba, Picea abies, Fagus sylvatica. The models obtained RMSErel of the models ranged from 26.8 to 36 % of RMSErel depending on the species considered.Finally, knot volumes have started to be studied. Although this work has not been fully completed, it already shows the importance of producing new models in order to fit the predicted knot patterns as closely as possible to reality. Moreover, the quantity of these compounds in the wood seems, at this stage of the study, to be too small to provide a large extractable resource, despite their great intrinsic richness. Their interest could therefore be more in the extraction of specific molecules
Mburu, Francis Gérardin Philippe. "Etude et valorisation de différents bois du Kenya Study and valorization of different Kenyan wood species /". [S.l.] : [s.n.], 2007. http://www.scd.uhp-nancy.fr/docnum/SCD_T_2007_0057_MBURU.pdf.
Pełny tekst źródłaDinkel, Olivier. "Etude et modélisation de l'endommagement d'un assemblage collé bois-bois sollicité en traction". Metz, 1997. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1997/Dinkel.Olivier.SMZ9706.pdf.
Pełny tekst źródłaJoints, which are essential parts of timber structures, must be designed to support expected loads during the life of the structure. The scarf joint is present in many elements, mainly in glulam structures. The behaviour before fracture of such joints is the object of this study. The cumulated damage of the joint is followed during the loading. The joint is considered as composed from wood, wood+adhesive, adhesive. A number of damage tests has been made. These tests have been purchased till fracture occurs. It is deduced from them that the adhesive part is the only one which is damaged during the loading. The corresponding damage law is identified and the model is verified with a finite elements computation
DINKEL, OLIVIER Pluvinage Guy. "ETUDE ET MODELISATION DE L'ENDOMMAGEMENT D'UN ASSEMBLAGE COLLE BOIS-BOIS SOLLICITE EN TRACTION /". [S.l.] : [s.n.], 1997. ftp://ftp.scd.univ-metz.fr/pub/Theses/1997/Dinkel.Olivier.SMZ9706.pdf.
Pełny tekst źródłaGrioui, Najla. "Etude thermocinétique de la pyrolyse du bois : application à la pyrolyse du bois d'olivier". Nancy 1, 2006. http://www.theses.fr/2006NAN10111.
Pełny tekst źródłaA theoretical and experimental study of thermo-kinetic of this wood particles pyrolysis has been developed. The thermophysical properties of the olive wood such as apparent density, porosity, permeability and thermal conductivity have been determined experimentally by different measurement methods. A kinetic measurements are carried out by thermogravimetric analysis in isothermal mode in the temperature range between 498 K and 648 K. The experimental curves obtained are interpreted by a kinetic model based on several decomposition stages. The kinetic model coupled with energy conservation equation leads to a non linear equations system which has been solved iteratively by using an implicit finite differences method. The obtained results are in good agreement with the available experimental data. The developed model is then applied to the pyrolysis of a cylindrical olive wood particle in different operating condition to simulate the effect of the reactor temperature and the particle size on the evolution of the temperature profile as well as the residual mass inside the thick particle
Ducoulombier, Julien. "Etude de l’opérade Swiss-cheese et applications à la théorie des longs noeuds". Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015USPCD090/document.
Pełny tekst źródłaThe aim of this work is to study the Swiss-Cheese operad, denoted by SCd, which is a relative version of the little cubes operad Cd.We show that the classical theorems in the context of uncolored operads can begeneralized to the relative case. From a pointed operad O (i.e. a two colored operad under π0(SC₁) ), webuild two semi-cosimplicial spaces (Oc ; Oo) such that the pair of semi-totalizations is weakly equivalentto an explicit SC₂-algebra. In particular, we prove that the pair (ℒ₁ ; n ; ℒm; n), composed of the space oflong knots and the space of long links, is weakly equivalent to an explicit SC₂-algebra.We study two homology theories, namely singular and Hochschild homology, of a pair of semicosimplicialspaces arising from a pointed operad. In this context, (H∗(sTot(Oc)) ; H∗(sTot(Oo))) and (HH∗(Oc) ; HH∗(Oo)) are equipped with an explicit H∗(SC₂)-algebra structure. We show that the mapintroduced by Bousfield between these two pairs is a morphism of H∗(SC₂)-algebras. This result helps us to understand the pair of spectral sequences computing (H∗(sTot(Oc)) ; H∗(sTot(Oo))). In particular wegive some conditions on a multiplicative symmetric operad so that the E² pages of the Bousfield spectral sequences are weakly equivalent to H∗(sTot(Oc)) and H∗(sTot(Oo)) as H∗(SC₂)-algebras. Finally we generalize our previous results, relying on a conjecture by Dwyer and Hess. We define acolored operad CCd and obtain an SCd₊₁-algebra from an operad morphism CCd → O. As a consequence, we prove that the couple of topological spaces (ℒᵈ₁ ; n ; T∞Imm(ᴷ))(Rᵈ ; Rⁿ)), where Ld₁;n is the space of long knots from Rd to Rⁿ and where T∞Imm(k)(Rᵈ ; Rⁿ) is the polynomial approximation of the (k)-immersions,is weakly equivalent to an explicit SCd+₁-algebra
Ngohe-Ekam, Paul-Salomon. "Etude expérimentale des propriétés thermophysiques des bois tropicaux". Lyon 1, 1992. http://www.theses.fr/1992LYO10146.
Pełny tekst źródłaBouzidi, Mourad. "Etude des protéines associées au canal sodium potentiel-dépendant neuronal". Aix-Marseille 2, 2002. http://www.theses.fr/2002AIX20672.
Pełny tekst źródłaBohnke, Isabelle. "Etude expérimentale et théorique des traitements thermiques du bois. Caractérisation physico-mécanique des bois traités". Paris, ENMP, 1993. http://tel.archives-ouvertes.fr/tel-00844044.
Pełny tekst źródłaLudosky, Daliena. "Emballages Légers en bois : Etude de la migration des molécules organiques du bois vers l'aliment". Thesis, Reims, 2015. http://www.theses.fr/2015REIMS008.
Pełny tekst źródłaFood packaging has existed for millennia; ever since man wished to transport solid or liquid foods that were gathered previously. As in the case most materials, wood could be a source of contamination by chemical or biological products. To date, there are no studies available that assess the migration potential of wood components in to food. Food in contact with materials, like wood, is subject to the European Regulation (EC) 1935/2004. In contrast to other materials, there is no specific directive for wooden food contact packaging. In France, the only specific regulation concerning "wood" dates from November 1945 and is very underdeveloped. This thesis aims to study various factors that influence the migration of organic compounds from wood to food when in direct or indirect contact with one another. The final outcome will be a simple methodology that can be applied to industrial packaging. At the national level, this innovative project is in response to the needs of both the French health authorities and the French wood packaging industry. And provide the information necessary to update the information contained in "wood material No. 2012-93” which will, in turn, give the food industry an analytical method and a point of reference
Rabot-Querci, Marie-Laure Zoulalian André. "Etude d'un dispositif de traitement des imbrûlés des appareils de chauffage indépendants au bois". [S.l.] : [s.n.], 2006. http://www.scd.uhp-nancy.fr/docnum/SCD_T_2006_0119_RABOT-QUERCI.pdf.
Pełny tekst źródłaRangsri, Wetchayan. "Etude expérimentale et numérique de l'essai d'indentation du bois". Montpellier 2, 2004. http://www.theses.fr/2004MON20079.
Pełny tekst źródłaHakkou, Saloua. "Etude de la migration des liquides dans le bois". Thesis, Nancy 1, 2010. http://www.theses.fr/2010NAN10059/document.
Pełny tekst źródłaWithin the framework of the restoration-conservation of ancient woods that belong to the historical and cultural heritage, one has to gain technical and scientific knowledge. This will allow to respect the integrity of the work and to ensure the reversibility of the interventions. While applying a preservative treatment or a wood strengthening product, it is for instance essential to know both the depth of penetration and the liquid migration path in order to control the effects of the operation.The work that is presented here is based upon the impregnation and flow in heterogeneous porous media of samples of various wood species according to the three reference sections (longitudinal-radial, longitudinal-tangential and transverse). To do so, colored liquids are used. This study is realized with original injection and exploration devices that have been developed in the laboratory.Studies were carried out to determine the effect of tyloses on the longitudinal permeability of three ring porous species. Air permeability in the axial direction was measured on cylindrical samples taken at various distances from the bark. The fine structure of any tyloses present was examined by Environmental Scanning Electronic Microscopy (ESEM)
Nebesarova, Ivana. "Etude d'un procédé de traitement pour l'association bois-polymère". Grenoble INPG, 1996. https://theses.hal.science/tel-00842820.
Pełny tekst źródłaSoulounganga, Patrice. "Etude de nouveaux traitements de protection du bois à base de polyglycérols". Nancy 1, 2002. http://www.theses.fr/2002NAN10032.
Pełny tekst źródłaWood is an heterogeneous material composed of tissue of vegetable origin. It is constituted of lignin, cellulose and hemicelluloses. Anisotropic and hygroscopic, it is sensitive to biotic and abiotic attacks, and requires the use of chemical treatments to be stabilized and preserved. However, the toxicity of certain products currently used, associated to the environmental constraints on greenhouse gases, justifies the search for new alternatives for wood preservation. Thus, the work undertaken during this research concerns the use of polyglycerol derivatives as wood dimensional stabilizing agents. Former studies have showed that polyglycerols (PG), soluble in water, increase wood dimensional stability, but are easily leached. To solve this problem, several solutions were developed. The first solution consists in the use of fatty esters of PG with low solubility in water. The results obtained depend on the solvent chosen for impregnation. Treatments in the form of microemulsion lead to better results of dimensional stabilization compared to treatments in organic phase. Moreover the hydrophobic character conferred to wood limits the virulence of rot fungi. A second approach consists in the use of polyglycerol methacrylate, easily obtained from polyglycerol and glycidol methacrylate. Water-borne treatment of wood leads, after drying, to the formation of a polymer insoluble in water able to improve dimensional stability of wood but also its resistance to the basidiomycetes. A microscopic study has allowed the localisation of the product in the wood cells wall, explaining the good dimensional stability observed. Lastly, the third approach considered relates to the formation of a polymeric network in wood obtained from PG, glyoxal and boric acid. Such a combination allows to stabilize wood dimensionally , to limit the depletion of boron compared to boric acid used alone and protect wood against fungi
Deces-Petit, Cyrille. "Etude des phases transitoires au cours du déroulage du bois". Paris, ENSAM, 1996. http://www.theses.fr/1996ENAM0027.
Pełny tekst źródłaOuartassi, Bajil Zoulalian André. "Etude numérique de la dynamique des transferts couplés au sein d'un milieu poreux". S. l. : Nancy 1, 2009. http://www.scd.uhp-nancy.fr/docnum/SCD_T_2009_0039_OUARTASSI.pdf.
Pełny tekst źródłaGaudin, Solène. "Etude de la durabilité photochimique de composites bois-polymères biodégradables". Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2008. http://tel.archives-ouvertes.fr/tel-00730997.
Pełny tekst źródłaAmmar, Salah. "Etude de la liquéfaction directe du bois : Solvolyse et hydrotraitement". Compiègne, 1990. http://www.theses.fr/1990COMP0314.
Pełny tekst źródłaThe direct liquefaction of wood has been treated by many researchers, but the process developed are not economical feasible in the present. The objective of this thesis is the investigation of an original method of liquefaction in two steps, the first is to dissolve the ligno-cellulosic material in an organic solvent to obtain ain liquid. The second is the catalytic hydrotreatment of this liquid (oil) in presence of different catalysts to reduce its viscosity and to obtain light fraction in a considerable quantity, which can be used as fuel. After a complete literature survey that justify the application of a two steps process, the thesis treat the solvolysis of wood constituent (glucose, cellulose, lignin) in phenolic media and in presence of acid sulphuric at 250°C. The aim of this study is to follow up the depolymerisation reactions of wood constituents from produced oil. Then a kinetic study of the solvolysis of wood pieces and powder has been carried on the other hand the optimal size of wood piece that can be dissolved in the solvent without melling was determined. Beyond size the mechanism reactional is controlled by the phenomena of solvent diffusion. The proposed model of the solvolysis kinetic although it did not take in consideration the geometry of the particles and their distribution, but it fit perfectly the experimental results. The final part of the thesis is the hydrogenation of the crude solvolysis oil at median hydrogen pressure in the presence of different catalysts. The optimal reactions conditions that give a good yield of light fraction were determined
Nguyen, Trung Viet Anh. "Multi renforcement du bois lamellé collé : Etude théorique et expérimentale". Marne-la-vallée, ENPC, 2010. http://www.theses.fr/2010ENPC1012.
Pełny tekst źródłaBendahmane, Mohamed. "Etude du comportement mécanique du bois avec nœuds : simulation numérique". Bordeaux 1, 1988. http://www.theses.fr/1988BOR10626.
Pełny tekst źródłaDaryanto, Hadi. "Etude des caractéristiques physico-mécaniques du bois imprégné et du bois densifié par imprégnation suivie d'une compression plastique". Grenoble : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37593816c.
Pełny tekst źródłaBirginie, Jean-Marc. "Etude du comportement de l'interface des collages sur bois (pin maritime) en fonction de l'environnement". Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37611937n.
Pełny tekst źródłaMarchal, Philippe. "Etude des émissions de fongicides à partir de bois traités : impact sur les compartiments aquatique et aérien". Metz, 1996. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1996/Marchal.Philippe.SMZ9603.pdf.
Pełny tekst źródłaWood preservation is not well known from general population. The principal aim of woob preservation is to protect wood timber against biological degradation that can appears during its use. As other industrial activities, wood preservation has environmental impacts. These last years, news developments are trying to evaluate and reduce these environmental impacts. This study invastigates the fungicide emissions from treated wood and also the impact of these emissions on the aquatic and atmospheric compartment. For the aquatic compartment, we have evaluated the toxicity of the wood, the active ingredient and the treated wood. This was assessed with some biotests including bacteria/plants/animals. For the atmospheric compartment, emissions of pesticide from treated wood were assessed with a small glass test chamber. The risk associated with these emissions and the pesticide concentrations were evaluated. Evaluations of the environmental impact of wood preservatives could in the future be part of the selection of news actives ingredients that have to be efficient and also safe for the environment
Rabot-Querci, Marie-Laure. "Etude d'un dispositif de traitement des imbrûlés des appareils de chauffage indépendants au bois". Nancy 1, 2006. http://docnum.univ-lorraine.fr/public/SCD_T_2006_0119_RABOT-QUERCI.pdf.
Pełny tekst źródłaThe main source of pollution from residential wood stoves is due to unburned gas and solid phase compounds in the fumes. In order to reduce these pollutants, we propose to use an exhaust gas-treating device to trap the particles in the chimney and to expose them to microwave to break them down. We first evaluated the emissions and the particulate matter (PM) characteristics from different fireboxes. Then we studied separately each function of the system : we trapped 50 % of PM with a 5 cm layer of refractory cement marbles placed in the chimney and then we heated the filter with microwave. About 200 kJ allowed us to clean completely the filter. This study showed that a microwave post-combustion system is particularly well adapted to particulate matter issued from wood combustion, in comparaison with other sources of energy regeneration. We also described the complete specifications of our device
Peydecastaing, Jérôme. "Etude de la modification chimique du bois par des anhydrides mixtes". Toulouse, INPT, 2008. http://ethesis.inp-toulouse.fr/archive/00001271/.
Pełny tekst źródłaThe chemical modification of wood with mixed anhydrides with aim to improve its properties has been investigated. Unsymmetrical acetic-fatty anhydrides were obtained after reaction between acetic anhydride and a fatty acid and two consecutive equilibrated reactions were put in evidence, yielding at equilibrium also a fatty anhydride in low proportion. Cellulose and Scots pine sawdust were treated by mixed anhydride mixtures and yielded lowly substituted mixed esters with different acetyl/fatty acyl ratios. The hydrophobicity of the esters, measured by water vapor sorption, was correlated to the total DS whereas the contact angle depended only on the fatty acyl substitution and was reached even at very low degree of substitution (DS=3. 10-4). The treatment of wood blocks resulted in high dimensional stability (Anti-swelling efficiency ASE of 90%) and depended on the total grafting whatever was the acyl group grafted. Mechanical properties of the treated wood were found to be preserved
Martin, Patrick. "Etude du comportement des poutres lamellées clouées boulonnées en flexion". Phd thesis, ENGREF (AgroParisTech), 2006. http://pastel.archives-ouvertes.fr/pastel-00003306.
Pełny tekst źródłaHaas, Frédéric. "Etude de la post-combustion des créosotes dans des appareils de chauffage au bois". Mulhouse, 1990. http://www.theses.fr/1990MULH0158.
Pełny tekst źródłaBatiot, Benjamin. "Etude expérimentale et numérique de la décomposition thermique du bois résineux". Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2014. http://www.theses.fr/2014ESMA0009/document.
Pełny tekst źródłaFires are complex and a variety of phenomena are involved. In order to study them, the up-scaling approach separates all the processes.Among them, the solid thermal decomposition has an important role to play. Source term, it reflects the amount, rate and nature of volatile compounds emitted and its numerical description is essential. The models used currently are formed by a law of variable speed (the Arrhenius law) coupled with a conversion function of mass for each species and a kinetic mechanism organizing all reactions between them. However, this model is based on the theories used in the gas phase and serious doubts might be raised with regard to the representativeness for application in the condensed phase.The thesis works exposed in this report are focused on the model development departing from the reactions and the processes the more fundamental in the condensed phase in order to permit the simulation of the solid kinetic decomposition. The second aspect concerns the study of this model to determine the resolution and the optimization method the most appropriate, the role of each parameter, the possible compensation mechanisms and the uniqueness of the solution.Finally, the entire process is applied to a complex material, the wood. The results obtained from a new approach developed in this work, show a significant improvement of the model to the physical and chemical aspects of the thermal degradation of solid materials
Odounga, Bernard. "Etude de la fissuration des bois tropicaux par mesures des champs". Thesis, Université Clermont Auvergne (2017-2020), 2018. http://www.theses.fr/2018CLFAC015/document.
Pełny tekst źródłaThe objective of the present work is to study experimentally and numerically the crackingbehavior of tropical woods from the Gabonese forest, namely : Milicia excelsa (iroko), Aucoumeaklaineana pierre (okume) and Pterocarpus soyauxii (padouk). This study focuseson the crack growth process in crack opening mode and mixed mode of these three speciesusing Modified Tension Shear (CTS) and Mixed Mode Crack Growth (MMCG) specimens.The specimens are mounted in an Arcan system and placed in an electromechanical testingmachine. The grid method is used to measure the displacement and strains fields near the tipcrack. These maps make it possible to obtain the opening and the length of the crack duringthe tests. The curves force showing the face as a function of the crack opening are deducedfrom the measurements. The experimental critical energy release rate G is evaluated by thecompliance method in imposed displacement. The results show an effect of the thickness oncracking. These results also made it possible to demonstrate a proportionality of the densitywith the parameters of rupture of these species. In mixed mode, after decoupling the modes(separation of mode 1 and mode 2), the values of G are presented as a function of to the cracklength. For Okume, for example, it was observed that the ratios of the energy release ratesof the two modes are constant, which justifies the intrinsic character of the cracking parameterswere obtained. Comparisons made with results from the literature review on temperatespecies of the same density showed similarities
Ast, Johann. "Etude de l'évolution des caractéristiques physico-chimiques des plaquettes forestières en fonction des modalités de stockage et de séchage". Thesis, Nancy 1, 2009. http://www.theses.fr/2009NAN10118/document.
Pełny tekst źródłaTo answer actual and future energetic and environmental issues, wood development is very important, notably with industrial and collective applications. To answer these needs and follow this development, lots of supplying structures of wood chips are being created. The main difficulty for these companies is guaranty good and stable raw material quality all time, notably concerning moisture content. The objective of this work is to research the most appropriate solutions to answer this problematic. So, the work begins by a bibliographical study that will help to understand the existing systems of drying; drying can be natural (under layer, under shelter …) or artificial (tunnel dryer, rotary dryer …). Then, experiments were put in place to understand and quantify more precisely natural drying parameters impact on wood chips and physico-chemical modifications on wood chips during storage. After, mathematic models are developed to traduce wood chip drying comportment, after models results are compared to experimental results. Finally, economical scenarios were performed to study the different solutions or combinations of solutions to dry wood chips in order to answer technical and economical industrial needs
Mahfoudh, Abir. "Etude de la production et de la caractérisation de composites bois-plastiques". Thesis, Université Laval, 2013. http://www.theses.ulaval.ca/2013/30168/30168.pdf.
Pełny tekst źródłaThe aim of this study was to produce and characterize composites made from wood flour and Ultra High Molecular Weight Polyethylene (UHMWPE). Firstly, the composites were initially prepared with wood sawdust provided from a sawmill and this study highlights particularly the use of raw materials in a powder form. Composites were prepared by a simple dry mixing technique and then compression molded. The wood content was up to 30%wt. The effect of wood content on morphology, density, hardness, and mechanical properties (tensile, torsion and flexion) was investigated. The results show that wood flour addition increased substantially all the moduli (up to 97%). The results show also that good dispersion and adhesion were achieved and wood flour addition increased significantly the mechanical properties of the composites.
OUELHAZI, NOURI. "Etude bidimensionnelle du sechage du bois : influence de la pression gazeuse interne". Poitiers, 1989. http://www.theses.fr/1989POIT2306.
Pełny tekst źródłaRozumek, Olivier. "Etude de la mouillabilité d'un matériau cellulosique, le bois relations mouillabilité-adhésion /". Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37600900v.
Pełny tekst źródłaDuprat, Frédéric. "Fiabilité des poteaux d'ossatures en béton armé à noeuds non déplaçables". Toulouse, INSA, 1993. http://www.theses.fr/1993ISAT0029.
Pełny tekst źródłaGauvin, Cécilia. "Etude expérimentale et numérique du comportement hygromécanique d’un panneau de bois : application à la conservation des tableaux peints sur bois du patrimoine". Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS066/document.
Pełny tekst źródłaConservation or restoration of many ancient wooden artefacts such as panel paintings is made difficult. In addition by issues linked to wood ageing, but also by the delicate situations originaling from asymmetrical moisture transfer phenomena through surface layer and wooden substrate. Conservators have tried to eradicate panels curvatures by moistening and flattening by pressure ; or simply in term of restoration act, by panel thinning followed by gluing on a rigid support. Between fortunate handling and absence of environmental control, some paint layers flaked material was partially lost, cracks opened. Indeed, the artefacts from cultural heritage that we handle are the witness of ancient times and practices, and may provide keys to the understanding of long-term behaviour of wooden structures. First, we have focused on the basic understanding of wood aging, we have made hygro-thermal treatment at 120degree C for several humidities and at 50degree C by hydric cycles on poplar samples (Populus alba). We underlined physical and chemical process and the reversible effect of heat-treated wood. Then we studied the behaviour of a painted panel part, and the relation between wood and preparatory layer. Our work shows clearly that the hygromechanical behaviour of the preparatory layer is very dependent on its composition, and that it is important to know precisely the layer composition before being able to analyse the global behavior of a panel painting. Finally, our work concerned experimental and numerical study of hygromechanical behaviour of a wooden panel, based on continuous mass weighting and measurement of strain by stereo-correlation during hygrothermal fluctuations of the environment. We decoupled experimentally the different components occurring in hygromechanics of panel painting, and we worked to set up a numerical tool allowing the simulation of observed phenomena. This thesis presents, on a fundamental point of view, the wooden panel behavior under climatic fluctuations, linking with cultural conservator actors (such as curators, conservators, scientists from cultural heritage dots) in order to develop tools to decision help
Cagnon, Thierry. "Etude de la fatigue d'origine hygroscopique d'un assemblage lamellé-collé en essences mélangées". Metz, 1993. http://docnum.univ-lorraine.fr/public/UPV-M/Theses/1993/Cagnon.Thierry.SMZ937.pdf.
Pełny tekst źródłaThe evolution of the strain-state of douglas fir-poplar glulam specimens is evaluated by analysis of the recorded pictures of a strained surface. The strain values are calculated from displacements of selected points, from digitalized images of the most strained surfaces of specimens aged during relative moisture cyclic conditions varying between 5% and 95%. No significant variations of maximum strain levels are revealed along the twelve 14-days drying-swelling cycles. These results are consistent with the gluebond integrity and stability of surrounding cracks, initialized during the first cycle
Jaubert, Philippe. "Etude et réalisation d'un dispositif de détection des singularités du bois par ultrasons". Bordeaux 1, 1985. http://www.theses.fr/1985BOR10603.
Pełny tekst źródłaLambert, Pascal. "Etude et réalisation de capteurs micro-ondes industriels pour la valorisation du bois". Nancy 1, 1990. http://www.theses.fr/1990NAN10499.
Pełny tekst źródłaJaubert, Philippe. "Etude et réalisation d'un dispositif de détection des singularités du bois par ultrasons". Grenoble : ANRT, 1985. http://catalogue.bnf.fr/ark:/12148/cb375948278.
Pełny tekst źródłaDiouf, Papa Niokhor. "Etude comparative de méthodes de mesure de l'activité antioxydante : applications aux extractibles de bois : liens avec la stabilité de la couleur du bois". Nancy 1, 2003. http://www.theses.fr/2003NAN10189.
Pełny tekst źródłaWe first studied three methods to measure antioxidant activity of phenolic molecules. In order to understand the role of the extracts in the stability of the surface coloured aspect of wood, we have studied, on the one hand, the antioxidant properties of the extractive substances of various wood species, and, on the second hand, the colour stability under solar type irradiation of these species. We measure total phenols in the various extracts. We selected some species taking into account the results obtained as for the stability of colour aspect and the extracts of which were used to impregnate unstable wood from the colour aspect point of view. The principal results are as follows. Content of extracts is not the main cause of colour stability. If correlation between the quantity of phenols in the extracts and antioxidant activity is good, correlation between antioxidant activity of the extracts of a species and the wood colour stability of the same species is weak
Jaouen, Gaëlle Fournier Djimbi Meriem. "Etude des stratégies biomécaniques de croissance des jeunes arbres en peuplement hétérogène tropical humide". S. l. : S. n, 2007. http://www.scd.uhp-nancy.fr/docnum/SCD_T_2007_0118_JAOUEN.pdf.
Pełny tekst źródłaWeiland, Jean-jacques. "Etude physico-chimique du traitement thermique du bois : Optimisation de paramètres du procédé de rétification". Grenoble INPG, 2000. http://tel.archives-ouvertes.fr/tel-00820822.
Pełny tekst źródłaMontacq, Noëlle. "Etude comparative des propriétés chimiques et morphologiques de bois résineux et feuillus soumis à l'hydrolyse flash". Grenoble INPG, 1988. http://www.theses.fr/1988INPG0087.
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