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Steric stabilisers were synthesised via the copolymerisation of styrene with acrylic macromonomers. The macromonomers were prepared by end capping reactions of poly 2-ethyl hexyl acrylate (PEHA) prepolymer with vinyl containing species. Preliminary reaction routes proceeded via the use of oxalyl chloride to create an acyl chloride intermediate followed by end capping with hydroxy ethyl methacrylate. This process was found to be inefficient due to the moisture sensitivity of the acyl chloride. The second route involved the direct end capping of the PEHA pre-polymer with glycidyl methacrylate (GMA). Macromonomer conversion levels were improved for the GMA route via the use of high temperatures and tertiary amine catalysts. An optimum set of conditions was achieved using 1.4 diazabicyclo [2.2.2.] octane as the catalyst and a reaction temperature of 160 QC. Non aqueous dispersion polymerisations of methyl methacrylate were performed. The factors affecting particle size in both single stage and twin stage polymerisation schemes were studied. Increases in the particle sizes of these dispersions were observed with increases in the total monomer concentration and also with decreases in the total stabiliser concentration. Increases in the particle size could also be achieved by increasing the proportion of the total monomer in the seed stage of the twin stage reaction and also by decreasing the proportion of the total stabiliser in the seed stage. The importance of the role of the seed upon the final particle size was firmly established. The rheology of these non aqueous dispersions was studied over a range of concentrations and under increasing shear stresses. At Iow and intennediate volume fractions the dispersions were observed to be predominantly Newtonian. Non-Newtonian behaviour was only observed at the extremes of the shear stress ranges studied. At high volume fractions of the dispersions non-Newtonian behaviour was observed over the range of shear stresses studied. Maximum volume fractions (~m) were calculated for these dispersions using the Kreiger-Dougherty equation. When these dispersions were blended in size ratios of 2:1 it was observed that 4 > m could be increased due to improved particle packing efficiency.

Yes / We introduce a novel approach to face models, which exploits the use of Partial Differential Equations (PDE) to generate the 3D face. This addresses some common problems of existing face models. The PDE face benefits from seamless merging of surface patches by using only a relatively small number of parameters based on boundary curves. The PDE face also provides users with a great degree of freedom to individualise the 3D face by adjusting a set of facial boundary curves. Furthermore, we introduce a uv-mesh texture mapping method. By associating the texels of the texture map with the vertices of the uv mesh in the PDE face, the new texture mapping method eliminates the 3D-to-2D association routine in texture mapping. Any specific PDE face can be textured without the need for the facial expression in the texture map to match exactly that of the 3D face model.

Cette thèse porte sur le développement d'un capteur de pixel monolithique CMOS utilisé pourl’identification et le comptage des particules ionisés dan l’espace avec un flux élevé. Un nouveauconcept pour l’identification de l’espèce des particules proposé dans la présente étude, est basésur l'analyse des amas de particules déclenchés. Pour valider ce nouveau concept, un capteur detaille complet, qui comprend la matrice de pixel sensible aux particules ionisés signal, une chaînede traitement du signal analogique, un convertisseur analogue numérique de 3 bits, et untraitement du signal numérique a été conçu dans un processus de 0.35 μm. Le capteur sortiedirectement des informations de flux à travers 4 canaux avec un débit de données très faible(80 bps) et dissipation d’énergie minimale (~ 100 mW). Chaque canal représente particules avecdifférentes espèces et les énergies. La densité maximum de flux mesurable est jusqu'à 108particules/cm2/s (coups s'accumulent < 5%). Un prototype à échelle réduite a été fabriqué et testéavec trois types d'illumination de rayonnement (rayons X, les électrons et laser infrarouge). Tousles résultats obtenus valident le nouveau concept proposé. Un moniteur de rayonnement spatialtrès miniaturisé basé sur un capteur de pixel CMOS peut être prévu. Le moniteur peut présente lesmêmes performances que les compteurs actuels, mais avec une dissipation de puissance réduited'un ordre de grandeur qu'un poids, un volume d'encombrement et un coût moindre. En outre, enraison de ses sorties de haut niveau et faible débit de données, aucune traitement supplémentairedu signal dehors du capteur est nécessaire, ce qui le rend particulièrement attrayant pour desapplications dan les petits satellitaires. / This thesis focuses on the development of a CMOS monolithic pixel sensor used for space ionizingparticles identification and counting in high flux. A new concept for single particle identification isproposed in this study, which is based on the analysis of particle triggered clusters. To validate thisnew concept, a full size sensor including the sensitive pixel matrix, an analogue signal processingchain, a 3-bit analogue to digital converter, and a digital processing stage was designed in a 0.35μm process. The sensor directly output particles flux information through 4 channels with a verylow data rate (80 bps) and minimal power dissipation (~ 100mW). Each channel representsparticles with different species and energies. The highest measurable flux density is up to 108particles/cm2/s (hits pile up < 5%). A reduced scale prototype was fabricated and tested with 3types of radiation illumination (X-ray, electrons and infrared laser). All the results obtained validatethe proposed new concept and a highly miniaturized space radiation monitor based on a singleCMOS pixel sensor could be foreseen. The monitor could provide measurements of comparable orbetter quality than existing instruments, but at around an order of magnitude lower powerconsumption, mass and volume and a lower unit cost. Moreover, due to its high level and low datarate outputs, no signal treatment power aside the sensor is required which makes it especiallyattractive for small satellite application.