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Fonctionnalisation de surfaces par microstructuration laser / Surfaces functionalization by laser microstructuringHairaye, Camille 16 June 2017 (has links)
Cette thèse porte sur la fonctionnalisation de surface par microstructuration laser. L’étude expérimentale a consisté à texturer des surfaces d’acier inoxydable avec une source laser impulsionnelle à fibre dopée Yb (1030 nm, 300 fs), dans le but de contrôler leur mouillabilité et de les rendre superhydrophobes. Par une optimisation des conditions d’irradiation, il est possible de conférer à la surface une structuration à double échelle de rugosité. Des structures d’une dizaine de micromètres sont réalisées par ablations successives selon un motif de lignes croisées, sur lesquelles se forment des nanostructures auto-organisées. La simulation du couplage de l’énergie dans la cible a permis de déterminer les paramètres opératoires pour limiter l’accumulation thermique en surface. L’étude fait clairement apparaître le rôle de la texturation dans l’apparition du caractère superhydrophobe de la surface, tout en soulignant l’influence des propriétés physico-chimiques du matériau. / This PhD thesis is about surface functionalization by laser microstructuring. The experimental study consists in texturing stainless steel surfaces with a pulsed Yb fibre laser source (1030 nm, 300 fs), in order to control their wettability and confer to them superhydrophobic properties. With an optimization of the irradiating conditions on the target, it is possible to confer to the surface a dual-scale roughness. By successive ablations according to a pattern of crossed lines, microstructures in the range of tens of micrometres are realized, on which self-organized nanostructures are superimposed. Simulation of the energy coupling in the material allows to determine the process parameters to be used, in order to limit the thermal accumulation and avoid the melting of the surface. This study reveals the role of the laser texturing in the apparition of the superhydrophobic character and emphasizes the influence of the physicochemical properties of the material.
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Functionalization and metallization of diamondoids / Fonctionnalisation et métallisation des diamantoïdesGunawan, Maria Agatha E. 21 May 2015 (has links)
Ces travaux de thèse développent des méthodes pour la synthèse de nouveaux organohybrides carbone-métal basés sur les diamantoïdes et le palladium.Les pressions de vapeur de divers diamantoïdes ont été mesurées grâce à un protocole original de mesures de l'état d'équilibre thermodynamique solide-vapeur. Leur relative volatilité a permis de réaliser des dépôts de diamontoïdes en phase vapeur, à diverses pressions (ambiante, vide primaire, et vide poussé) sur des substrats comme le silicium ou le mica. Les observations au MEB ont montré que, selon le type de groupes fonctionnels présents sur le diamantoïde, différentes formes cristallines peuvent être produites (tiges, aiguilles, triangles, formes octaédriques tronquées).L’OMCVD de palladium sur les diamantanes fonctionnalisés montre que le palladium se dépose préférentiellement sur le substrat du silicium plutôt que sur les cristaux de diamantoïdes portant des groupes hydroxy ou fluor. Nous avons alors envisagé la synthèse de nouveaux diamontoïdes portant des groupes phosphino, qui pourraient former une liaison covalente entre le diamontoïde modifié et le palladium.Un ensemble complet de diamondoïdes fonctionnalisés par des phosphines a été synthétisé. Certaines nouvelles phosphines primaires ont révélées une stabilité à l’air inattendue.Il a été montré que l’utilisation de phosphine P(III) comme sites d'ancrage a permis la formation du matériau hybride Pd@PH2-Diam-OH. Différents caractérisations (XPS, MEB, MET, et EDX) ont montré que le matériau Pd@PH2-Diam-OH formé est isolant, et présente des interactions Pd–P. / The thesis deals with development of synthetic methods for preparation of novel carbon-metal organohybrid based on diamondoid and palladium. The vapor pressure of various diamondoids was measured from a new measurement protocol at solid-vapor thermodynamic equilibrium state. Their volatile tendency opened a possibility to do deposition from gas phase and at various pressure (ambient, primary vacuum, and high vacuum) of diamondoids on silicon or mica substrates. SEM observations have shown that depending on the type of functional groups on the diamondoid, different crystal shapes can be produced (rods, needles, triangles, truncated octahedral form).OMCVD of palladium on functionalized diamantanes showed that Pd deposition occurs preferentially on the oxide native layer on silicon substrates than on diamondoid crystals bearing hydroxyl or fluorine groups. This urged the synthesis new diamondoids with phosphino groups in order to make strong covalent bonding between the modified diamondoid and palladium.A full set of functionalized diamondoid phosphines were synthesized with unexpected air-stability of some primary diamondoid phosphines were observedIt has been shown that the use of P(III) phosphine as anchoring sites allowed the formation of hybrid material Pd@PH2-Diam-OH. Different characterizations (XPS, SEM, TEM, and EDX) indicated that an insulator material Pd@PH2-Diam-OH formed during the CVD deposition with P–Pd interaction.
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Cannabidiol : exploring new synthetic pathways for late-stage functionalizationRigaut, Sophie 08 1900 (has links)
L’intérêt grandissant suscité par les propriétés thérapeutiques exhibées par les cannabinoïdes a motivé la naissance du projet décrit dans ce mémoire de maîtrise. La synthèse efficace de différents cannabinoïdes est devenue essentielle afin de pouvoir mieux comprendre les mécanismes régulant les propriétés médicales de ces composés ainsi que pour promouvoir le développement de nouveaux traitements médicamenteux. Le cannabidiol est d’intérêt particulier en raison des propriétés anti-inflammatoires, et anticancéreuses exhibées par cette molécule. Ce projet vise à explorer différentes routes permettant la fonctionnalisation du cannabidiol en phase avancée dans le but de faciliter l’accès aux dérivés de ce produit naturel.
La première partie de ce mémoire se concentre sur le développement d’une voie de synthèse permettant la fonctionnalisation d’un précurseur du cannabidiol en utilisant le 1,3-diméthoxybenzène, un produit de départ abordable et commercialement disponible. L’approche proposée comporte six étapes et s’appuie sur une réaction de Diels-Alder pour générer l’adduit bicyclique du cannabidiol. Plusieurs routes ont été explorées pour obtenir la fonctionnalisation de ce précurseur, à savoir une borylation de Hartwig-Miyaura et une bromination du cycle aromatique.
La deuxième partie de ce projet se concentre sur la fonctionnalisation du cannabidiol en phase avancée en s’appuyant sur la fonctionnalité de l’amide de Weinreb. Ces travaux ont abouti au développement d’une voie de synthèse efficace et durable pour la production de l’olivetol, un fragment clé pour la production à grande échelle de cannabidiol dans l’industrie pharmaceutique. Cette méthode se base sur une approche en quatre étapes s’appuyant sur un amide de Weinreb en utilisant un produit de départ abordable, l’acide 3,5-dimethoxy benzoïque. La synthèse de l’amide de Weinreb puis de la cétone correspondante, suivie d’une réduction de Wolff-Kishner, et enfin la démethylation du substrat ont permis d’obtenir le produit désiré. La versatilité de cette approche tolère une fonctionnalisation variée de la molécule, permettant la synthèse potentielle de divers dérivés de l’olivetol. / The increasing interest around the therapeutic possibilities offered by cannabinoids was the motivation for the project described in this Master’s thesis. The efficient synthesis of various CBs has become critical to deepen the understanding of the mechanisms behind the medical properties of cannabinoids as well as for the development of novel drug treatments. Cannabidiol is of particular interest as the molecule exhibits anti-inflammatory, and anticarcinogenic properties. This work aims to explore different routes to enable the late-stage functionalization of cannabidiol in order to easily access derivatives of the natural compound.
The first part of this work focuses on developing a route enabling the functionalization of the cannabidiol precursor utilizing the affordable and commercially available starting material 1,3-Dimethoxybenzene. The proposed six-step approach relies on a Diels-Alder reaction to generate the bicyclic adduct of cannabidiol. Several routes were then explored to obtain the functionalization of the precursor namely a Hartwig-Miyaura borylation and a bromination of the aromatic ring.
The second part of this project focuses on the functionalization of cannabidiol relying on the Weinreb amide functionality. This work led to the development of an efficient and sustainable route for the synthesis of olivetol, a key fragment for the large-scale production of cannabidiol within the pharmaceutical industry. The method relies on a four-step approach relying on a Weinreb amide synthesized using the affordable 3,5-Dimethoxybenzoic acid. The synthesis of the Weinreb amide followed by the formation of the corresponding ketone, subsequent Wolff-Kishner reduction, and finally demethylation of the substrate allowed to generate the desired product. The versatility of the approach allows for variations in functionalization, enabling potential formation of various olivetol derivatives.
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Reactivity of rhodium-heteroatom bonds: from catalytic bond activation to new strategies for olefin functionalizationvan Rooy, Sara Emily 05 1900 (has links)
Rhodium complexes bearing multidentate nitrogen donor ligands were investigated for their ability to promote alkyne and olefin functionalization reactions. This thesis work is comprised of two projects in which rhodium-heteroatom reactivity is investigated: P-H bond activation reactions and olefin functionalizations via rhodaoxetane intermediates.
[Tp*Rh(PPh3)2] [Tp* = hydrotris(3,5-dimethylpyrazolyl)borate] and
[Tp*Rh(cod)]2 (cod = cyclooctadiene) were evaluated for their activity in alkyne hydrophosphinylation in comparison to known catalysts for this reaction. [Tp*Rh(PPh3)2]and [Tp*Rh(cod)]2 were both shown to effect hydrophosphinylation of 1-octyne with diphenylphosphine oxide with high regioselectivity but moderate yields in comparison with Wilkinson's catalyst [C1Rh(PPh3)3]. [Tp*Rh(PPh3)2] was further shown to effect hydrophosphinylation of a range of aromatic and aliphatic alkynes with diphenylphosphine oxide, in each case exclusively providing the E-linear vinylphosphineoxide product. 1H and 31P NMR spectroscopy provided evidence that alkyne hydrophosphinylation in the presence of pyrazolylborate rhodium complexes follows an analogous mechanism to that proposed for this reaction catalyzed by [C1Rh(PPh3)3] or[C1Rh(cod)]2.
The 2-rhodaoxetane [(TPA)Rhmec2_,-4u, 0-2-oxyethypr BPh4- (TPA = tris[(2-pyridal)methyl]amine) was investigated for its potential as an intermediate in proposed functionalization reactions of olefins. RTPA)Rh111(K2-C,0-2-oxyethyl)]+ BPh4- was prepared by two published methods with limited success. A third method involved the use of nitrous oxide to oxygenate [(12-ethene)(K4-TPA)Rh1]+ to RTPA)Rh1110(-2-C,0-2-oxyethyDr. Only a trace amount of [(TPA)Rhmoc2 -C,0-2-oxyethypr was observed in the 1I-1 NMR spectrum of this reaction mixture. Initial test reactions of [(TPA)Rhilioc2_C,0-2-oxyethypr combined with substrates (aniline, toluenesulfonamide, phenylboronic acid, or benzaldehyde) were inconclusive since the results were obscured by the impurity of the samples.
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Reactivity of rhodium-heteroatom bonds: from catalytic bond activation to new strategies for olefin functionalizationvan Rooy, Sara Emily 05 1900 (has links)
Rhodium complexes bearing multidentate nitrogen donor ligands were investigated for their ability to promote alkyne and olefin functionalization reactions. This thesis work is comprised of two projects in which rhodium-heteroatom reactivity is investigated: P-H bond activation reactions and olefin functionalizations via rhodaoxetane intermediates.
[Tp*Rh(PPh3)2] [Tp* = hydrotris(3,5-dimethylpyrazolyl)borate] and
[Tp*Rh(cod)]2 (cod = cyclooctadiene) were evaluated for their activity in alkyne hydrophosphinylation in comparison to known catalysts for this reaction. [Tp*Rh(PPh3)2]and [Tp*Rh(cod)]2 were both shown to effect hydrophosphinylation of 1-octyne with diphenylphosphine oxide with high regioselectivity but moderate yields in comparison with Wilkinson's catalyst [C1Rh(PPh3)3]. [Tp*Rh(PPh3)2] was further shown to effect hydrophosphinylation of a range of aromatic and aliphatic alkynes with diphenylphosphine oxide, in each case exclusively providing the E-linear vinylphosphineoxide product. 1H and 31P NMR spectroscopy provided evidence that alkyne hydrophosphinylation in the presence of pyrazolylborate rhodium complexes follows an analogous mechanism to that proposed for this reaction catalyzed by [C1Rh(PPh3)3] or[C1Rh(cod)]2.
The 2-rhodaoxetane [(TPA)Rhmec2_,-4u, 0-2-oxyethypr BPh4- (TPA = tris[(2-pyridal)methyl]amine) was investigated for its potential as an intermediate in proposed functionalization reactions of olefins. RTPA)Rh111(K2-C,0-2-oxyethyl)]+ BPh4- was prepared by two published methods with limited success. A third method involved the use of nitrous oxide to oxygenate [(12-ethene)(K4-TPA)Rh1]+ to RTPA)Rh1110(-2-C,0-2-oxyethyDr. Only a trace amount of [(TPA)Rhmoc2 -C,0-2-oxyethypr was observed in the 1I-1 NMR spectrum of this reaction mixture. Initial test reactions of [(TPA)Rhilioc2_C,0-2-oxyethypr combined with substrates (aniline, toluenesulfonamide, phenylboronic acid, or benzaldehyde) were inconclusive since the results were obscured by the impurity of the samples.
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Reactivity of rhodium-heteroatom bonds: from catalytic bond activation to new strategies for olefin functionalizationvan Rooy, Sara Emily 05 1900 (has links)
Rhodium complexes bearing multidentate nitrogen donor ligands were investigated for their ability to promote alkyne and olefin functionalization reactions. This thesis work is comprised of two projects in which rhodium-heteroatom reactivity is investigated: P-H bond activation reactions and olefin functionalizations via rhodaoxetane intermediates.
[Tp*Rh(PPh3)2] [Tp* = hydrotris(3,5-dimethylpyrazolyl)borate] and
[Tp*Rh(cod)]2 (cod = cyclooctadiene) were evaluated for their activity in alkyne hydrophosphinylation in comparison to known catalysts for this reaction. [Tp*Rh(PPh3)2]and [Tp*Rh(cod)]2 were both shown to effect hydrophosphinylation of 1-octyne with diphenylphosphine oxide with high regioselectivity but moderate yields in comparison with Wilkinson's catalyst [C1Rh(PPh3)3]. [Tp*Rh(PPh3)2] was further shown to effect hydrophosphinylation of a range of aromatic and aliphatic alkynes with diphenylphosphine oxide, in each case exclusively providing the E-linear vinylphosphineoxide product. 1H and 31P NMR spectroscopy provided evidence that alkyne hydrophosphinylation in the presence of pyrazolylborate rhodium complexes follows an analogous mechanism to that proposed for this reaction catalyzed by [C1Rh(PPh3)3] or[C1Rh(cod)]2.
The 2-rhodaoxetane [(TPA)Rhmec2_,-4u, 0-2-oxyethypr BPh4- (TPA = tris[(2-pyridal)methyl]amine) was investigated for its potential as an intermediate in proposed functionalization reactions of olefins. RTPA)Rh111(K2-C,0-2-oxyethyl)]+ BPh4- was prepared by two published methods with limited success. A third method involved the use of nitrous oxide to oxygenate [(12-ethene)(K4-TPA)Rh1]+ to RTPA)Rh1110(-2-C,0-2-oxyethyDr. Only a trace amount of [(TPA)Rhmoc2 -C,0-2-oxyethypr was observed in the 1I-1 NMR spectrum of this reaction mixture. Initial test reactions of [(TPA)Rhilioc2_C,0-2-oxyethypr combined with substrates (aniline, toluenesulfonamide, phenylboronic acid, or benzaldehyde) were inconclusive since the results were obscured by the impurity of the samples. / Science, Faculty of / Chemistry, Department of / Graduate
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Melodic Drumming in Contemporary Popular Music: An Investigation into Melodic Drum-Kit Performance Practices and Repertoire.Jordan, Michael, mjordan@iprimus.com.au January 2009 (has links)
This project is an investigation of melodic drum-kit practices in popular and contemporary music. The development of melodic drum-kit playing techniques has helped create a more inclusive role for drum-kit players within ensembles and has increased the potential for drum-kit players to present solo elements in performance. The project artefacts of my research are six compositions presented on CD. They demonstrate performance and compositional techniques that encourage a melodic approach to drum-kit performance. My research involved several methodological approaches these included: a) professional practice-based research, b) music composition and transcription, c) interviews with significant musicians familiar with drum-kit melodic practices and d) elements of autoethnography. I refer to particular drum-kit performance techniques and practices such as mirroring, thinking melodically, spatial relationships between drum-kit instruments and ensemble players, as well as, internalising melodic and harmonic ideas and being in the moment. I have shown in my compositional project that melodic elements in drum-kit performance and composition encourage a broader and more inclusive role for drummers in improvised performance. This is evident in the ensemble versions of compositions submitted as part of this study.
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The Role of Melodic Contour in Linguistic ProcessingWang, Yun January 2017 (has links)
No description available.
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Symbolic structure in the music of GubaidulinaNeary, Fay Damaris January 1999 (has links)
No description available.
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Macro-, Micro- and Nanospheres from Cellulose : Their Preparation, Characterization and UtilizationCarrick, Christopher January 2014 (has links)
The structure of a polymeric material has a great influence in many fundamental scientific areas as well as in more applied science, since it affects the diffusion, permeability, mechanical strength, elasticity, and colloidal properties of the materials. The results in this thesis demonstrate that it is possible to fabricate solid and hollow cellulose spheres with a cellulose shell and encapsulated gas, liquid or solid particles and with a sphere size ranging from a few hundreds of nanometres to several millimetres, all with a tailored design and purpose. The sizes of the different spheres have been controlled by three different preparation methods: large cellulose macrospheres by a solution solidification procedure, hollow micrometre-sized cellulose spheres by a liquid flow-focusing technique in microchannels, and nanometre-sized cellulose spheres by a membrane emulsification technique. The spheres were then modified in different ways in order to functionalize them into more advanced materials. This thesis demonstrates how to control the cellulose sphere dimensions and the wall-to-void volume ratio, the elasticity and the functionality of the spheres as such, where they were prepared to be pH-responsive, surface specific and X-ray active. These modifications are interesting in several different types of final materials such as packaging materials, drug release devices or advanced in vivo diagnostic applications. In the more fundamental science approach, surface-smooth solid cellulose spheres were prepared for characterization of the macroscopic work of adhesion when a cellulose surface is separated from another material. Using these ultra-smooth macroscopic cellulose probes, it is possible to measure the compatibility and the surface interactions between cellulose and other materials which provide an important tool for incorporating cellulose into different composite materials. / <p>QC 20140829</p>
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