632 research outputs found

    Nanometric TiO 2 as NBBs for functional organic-inorganic hybrids with efficient interfacial charge transfer

    No full text
    International audienceThe purpose of this work is to establish a fabrication method for new electronic materials: organic-inorganic p-MAPTMS / titanium-oxo-alkoxy hybrids. The size-selected 5.2-nm TiO 2 nanoparticles (Nano Building Blocks-NBB) are generated in a sol-gel reactor with turbulent fluids micromixing. The surface exchange between propoxy and MAPTMS groups under vacuum pumping results in a stable nanoparticulate precursor available for 2-photon laser polymerisation. The hybrids demonstrate quantum yield of photoinduced charges separation 6 % and can steadily trap photoinduced electrons at number density of 6% Ti atoms. The materials are suitable for 3D-microstructuring

    A student\u27s guide to behavioral optometry: One contribution to a larger work

    Get PDF
    This thesis project is one contribution to a larger collective work entitled A Student\u27s Guide to Behavioral Optometry. The intent behind this study guide is to aid first year optometry students in their understanding of the course material presented in Behavioral Optometry 562. Former students of this course have taken the course notes and rewritten them from students\u27 perspectives. Included in this study guide are diagrams and self-assessment tools to complement the material

    The Role of Angler Behaviour on the Post-Release Locomotor Activity and Depth Selection of Angled Fish Revealed by Biologgers

    Get PDF
    Catch-and-release is a growing practice worldwide with the number of fish released each year in the billions. Few studies have been able to observe fine-scale behaviour in the wild. My goal was to assess fish behaviour in the wild following various angling scenarios using externally attached biologgers. Chapter 2 assessed the impacts of air exposure on the post-release behaviour of three gamefish species. My data suggested that Northern Pike that were air-exposed exhibited decreased swimming activity immediately after release. In chapter 3, I evaluated the efficacy of assisted recovery methods at reducing post-release behavioural impairments in Rainbow Trout. I determined that assisted recovery was effective at reducing equilibrium impairments, especially if cold water was used. Behavioural data was gathered using externally attached biologgers equipped with tri-axial accelerometers. These results suggest that the behavioural impacts of a C&R event can vary greatly with the species targeted, angler behaviour, and environmental factors

    Fabrication And Characterization Of Porous Alumina

    Get PDF
    Porous alumina have been widely used in engineering applications. In this study, porous alumina has been fabricated using polymeric sponge and slip casting methods. In polymeric sponge method (using polyurethane sponge (PU)), type of binders (polyvinyl alcohol (PVA), wheat starch (WS) and tapioca starch (TS)), solid loadings (50, 60, and 70 wt. %), sintering temperatures (1200, 1300, 1400 and 1500 oC) and slurry recoating technique were studied. In slip casting method, polyvinyl alcohol (PVA) has been used as a binder and pore former, and the effect of solid loadings (50, 60, 70 and 75 wt. %) and sintering temperatures (1200, 1300, 1400 and 1500 oC) were studied. Results showed that porous alumina produced by slip casting method consisted of closed pores, pore size in ther range of 78 to 300 μm and higher compressive strength (1.22- 42.79 MPa). Whereas, porous alumina produced by polymeric sponge consisted of interconnected pores, pore size in the range of 800 μm to 1.5 mm and higher percentage of porosity (77.66 to 95 %). However, using recoating technique, it showed the compressive strength of the samples was improved. In conclusion, porous alumina produced by polymeric sponge method in this study has a potential to be used as hot gas filtration, whereas; porous alumina produced by slip casting method has a potential use as a catalysis

    Determining the Role of FKBPL Signalling in Cardiac Fibrosis and Heart Disease

    Full text link
    University of Technology Sydney. Faculty of Science.Cardiovascular Diseases (CVDs) are the leading cause of mortality worldwide and hold a huge socioeconomic burden. Clinical manifestations of CVD are often heterogeneous and caused by various risk factors and co-morbidities that can lead to patient mortality and heart failure (HF). This multifactorial nature of CVD creates difficulty in determining the exact mechanisms of CVD pathophysiology and results in poor patient prognosis. In this thesis, we aim to elucidate key mechanisms in CVD pathophysiology including the emerging role of an immunophilin protein, FK506-binding protein like (FKBPL). Overall, the adverse impact of E-Cigs on cardiovascular health that increases the expression of anti-angiogenic FKBPL and inflammatory markers, was demonstrated. FKBPL shows promising therapeutic target potential in cardiac hypertrophy and fibrosis and could be used in the diagnosis of HFpEF in conjunction with other well-established biomarkers including NT-pro-BNP and Gal-3. Further research is needed to specifically elucidate the role of cardiac remodelling biomarkers including FKBPL in DM population

    Etude et modélisation de l'interface graphite/électrolyte dans les batteries lithium-ion

    Get PDF
    This work relates to the lithium ion battery field. The purpose of this study is tobetter understand the behavior of graphite electrodes by focusing on the formationof a passive layer named Solid Electolyte Interface (SEI) which is formed at thegraphite/electrolyte interface. This work has led us to put forward models whichcan explain the SEI formation and identify the reactions which take place in alithium ion battery.The SEI results from reactions between graphite electrode, lithium ions and organicmolecules from the electrolyte during the first charge of the lithium ion battery. It ismainly composed of decomposition products from the electrolyte. Consumed lithiumions can no longer be used in the next cycle. The SEI is therefore responsible for theirreversible capacity during the first formation cycle which is the charge loss betweenthe intercalation process and the deintercalation process. It is necessary to betterunderstand the impact of the formation conditions and other parameters in orderto control and limit the irreversible charge loss. Lithium ion battery performancesdepend on this irreversible capacity, this value has to be reduced in order to maximizethe amount of exchanged lithium ions between negative and positive electrodes. TheSEI stability will determine the electrode behavior upon cycling.In this thesis, we chose to study the graphite behavior by testing several electrolytecompositions and graphite particle sizes in electrochemical cells similar to areal battery. Electrochemical techniques (galvanostatic cycling and electrochemicalimpedance spectroscopy) and surface analyses (X-ray photoelectron spectroscopy,scanning electron microscopy) will be combined. These results helped us to developa new model of the SEI formation.For the electrolyte, we chose to study the effect of the solvent (propylene carbonate)and the additive (vinylene carbonate). Both components are commonly used inthe electrolyte for commercial lithium ion batteries. For the graphite electrode, thechoice of graphite particles is essential because each graphite family has its ownsurface chemistry (basal and prismatic surfaces) which can react in many wayswith the electrolyte. Two graphite particles, with specific sizes and morphologiesare studied. They are separately used as active materials for negative electrodes inlithium ion batteries. Our unique approach is to prepare graphite electrodes basedon a mix of both particles with various compositions and then test the electrode225performances. After testing several formation conditions such as the cycling rateand the temperature, we found the ideal formation conditions for minimizing theelectrolyte decomposition and optimizing the film quality.Finally, based on all the characterization methods, we came to a better understandingof the film formation process. In this way, we have improved this essentialpreliminary step which can now lead to more durable cycling performances overtime. This study can have a major impact on the industrial level. The formationmodel cast a new light on the formation process and can therefore help to makeefficient graphite electrodes.Cette thèse se positionne dans le domaine des batteries lithium-ion. Elle a pourobjectif de mieux comprendre le fonctionnement de l’électrode négative de graphiteen étudiant le processus de formation du film de passivation, couramment appeléSEI (Solid Electrolyte Interface) créé à l’interface avec l’électrolyte. Ce travail nousa conduit à proposer des modèles pouvant expliquer comment se forme la SEI et àidentifier les phénomènes qui entrent en jeu dans le fonctionnement de la batterie.La SEI résulte de la réaction entre l’électrode de graphite, les ions lithium et les moléculesorganiques de l’électrolyte qui survient lors du premier processus d’insertion.Elle est principalement composée des produits de décomposition de l’électrolyte etles ions lithium consommés ne sont plus échangeables. Elle est donc responsable dela capacité irréversible observée lors du premier cycle de formation, correspondantà la différence de capacité entre le processus d’insertion et le processus de désinsertion.Il est donc essentiel de mieux comprendre les paramètres qui l’influencentpour pouvoir ainsi la contrôler et limiter la perte irréversible de capacité. Les performancesen capacité de l’élément lithium-ion sont directement liées à cette valeurde capacité irréversible, elle doit être limitée afin de maximiser la quantité d’ionslithium échangée entre l’électrode négative et l’électrode positive. La stabilité dela SEI conditionne ensuite le comportement en cyclage de l’électrode au cours dutemps.Dans ce mémoire de thèse, nous avons choisi de caractériser le comportement del’électrode de graphite en faisant varier la nature de l’électrolyte et la taille desparticules de graphite tout en restant le plus proche possible du fonctionnementd’une vraie batterie. Au travers des techniques de caractérisations électrochimiques(cyclage galvanostatique, spectroscopie d’impédance) associées à des techniques decaractérisation de surface (spectroscopie de photoélectrons X, microscopie électroniqueà balayage), les résultats obtenus ont permis de proposer un nouveau modèlede formation de la SEI.Pour l’électrolyte, nous avons choisi de ne regarder que l’effet du solvant (le carbonatede propylène) et de l’additif (le carbonate de vinylène). Ces deux composésentrent dans la composition des électrolytes utilisés dans les éléments lithium-ioncommerciaux. Pour l’électrode de graphite, le choix des particules s’avère primordialpuisque chaque type de particules possède une chimie de surface spécifique (plans223basaux ou plans prismatiques) susceptible de réagir différemment vis-à-vis de l’électrolyte.Deux particules de graphite, de taille et de morphologie différentes, ont étéétudiées. Elles sont utilisées séparément en tant que matière active dans les électrodesnégatives des batteries lithium-ion. Notre spécificité est d’avoir préparé desélectrodes constituées par un mélange de ces deux particules et de les avoir ensuitecaractérisées en formation. L’application de conditions de fonctionnement différentescomme le régime de cyclage et la température d’essai ont mis en évidence les valeursidéales conduisant à minimiser la dégradation de l’électrolyte et à optimiser laqualité du film.Nous avons abouti, au travers de l’ensemble des méthodes de caractérisations misesen oeuvre, à une meilleure compréhension des mécanismes de formation du film depassivation permettant ainsi d’améliorer cette étape essentielle à la pérennité desperformances de l’électrode dans le temps. Ce travail a donc un réel impact auniveau industriel. Le modèle de formation proposé apporte un éclairage nouveau auprocessus de formation et peut permettre également d’aider en amont à la fabricationdes particules de graphite

    Utilising the Intel RealSense camera for measuring health outcomes in clinical research

    Get PDF
    Applications utilising 3D Camera technologies for the measurement of health outcomes in the health and wellness sector continues to expand. The Intel® RealSense™ is one of the leading 3D depth sensing cameras currently available on the market and aligns itself for use in many applications, including robotics, automation, and medical systems. One of the most prominent areas is the production of interactive solutions for rehabilitation which includes gait analysis and facial tracking. Advancements in depth camera technology has resulted in a noticeable increase in the integration of these technologies into portable platforms, suggesting significant future potential for pervasive in-clinic and field based health assessment solutions. This paper reviews the Intel RealSense technology’s technical capabilities and discusses its application to clinical research and includes examples where the Intel RealSense camera range has been used for the measurement of health outcomes. This review supports the use of the technology to develop robust, objective movement and mobility-based endpoints to enable accurate tracking of the effects of treatment interventions in clinical trials

    Multiphase photo-capillary reactors coated with TiO2 films: preparation, characterization and photocatalytic performance

    Get PDF
    Quartz capillaries were assessed as multiphase photocatalytic reactors. The tested reaction was the salicylic acid (2-dihidroxibenzoic acid) oxidation. The catalyst (TiO2) was either in slurry or immobilized by sol-gel method onto the capillary wall. All experiments were conducted under oxygen flow and Taylor flow hydrodynamic regime. TiO2 Films were characterized by Raman spectroscopy, diffuse reflectance UV-Vis spectroscopy and scanning electronic microscopy. The effect of two synthesis variables was established. These variables were volumetric ratio of precursors solutions (i-PrO:2-propanol:nitric acid) and number of capillary coating cycles. These variables were found to importantly affect film homogeneity and oxidation rate. The highest initial reaction rate (106.32x10-6 mol dm-3s-1) was obtained when using the TiO2 as film prepared with a precursors volumetric ratio of 1:15:1 and with two coating cycles. For comparison purposes, the same oxidation process was conducted in a stirred reactor and it was found that the reaction rate value is diminished by almost four times in comparison with that obtained under Taylor flow in the capillary reactor. Selectivity was found to be dependant on the type of catalyst addition, slurry or immobilized. Catalytic films employed in this non-common reaction system were 2 reused three times losing less than 10% of their photocatalytic activity. The photonic efficiency was found to be two orders of magnitude higher in the coated capillary reactor than in the slurry stirred reactor.L. Hurtado acknowledges CONACYT-Mexico the scholarship No. 56499. Project PRODEP for advanced oxidation processes is also acknowledged for financial support
    corecore