Isotherms of one atom thick film of adsorption for propane on purified Hipco single-walled carbon nanotube were experimentally studied at 6 different temperatures ranging from 190K up to 280K. In these isotherm measurements, two substeps were clearly present at temperatures between 190K and 220K. For propane adsorption, two different groups of binding energy sites on the nanotubes were determined by the outcome. Also, we found that those substeps were gradually smearing as the temperature increases. These features of propane adsorption were compared to the same features that were present for the case of ethane and butane adsorption on the same sample. In comparison, high binding energy sites revealed by low pressure substeps were clearly visible in all the cases. However, the high pressure substep that represents a low binding energy site, external surface site, was smearing as carbon chain length of adsorbed alkanes increase. For the case of butane adsorption, the substep was not pronounced in the alkanes' isotherms at the relative temperatures. We also determined a decrease in the values of specific surface area of the nanotubes and an increase in the values of binding energies of alkanes on the substrate were increased as the sizes and lengths of linear carbon alkanes were increased.

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Yes / Objectives This work investigated the impact of spray drying variables such as feedconcentration, solvent composition and the drying mode, on the micromeriticproperties of chlorothiazide sodium (CTZNa) and chlorothiazide potassium(CTZK).Methods Microparticles were prepared by spray drying and characterised usingthermal analysis, helium pycnometry, laser diffraction, specific surface area analysisand scanning electron microscopy.Key findings Microparticles produced under different process conditions pre-sented several types of morphology.To systematise the description of morphology ofmicroparticles, a novel morphology classification system was introduced. The shapeof the microparticles was described as spherical (1) or irregular (2) and the surfacewas classified as smooth (A) or crumpled (B). Three classes of morphology of micro-particles were discerned visually: class I, non-porous; classes II and III, comprisingdiffering types of porosity characteristics. The interior was categorised as solid/continuous (a), hollow (b), unknown (g) and hollow with microparticulate content(d). Nanoporous microparticles of CTZNa and CTZK, produced without recircula-tion of the drying gas, had the largest specific surface area of 72.3 and 90.2 m2/g,respectively, and presented morphology of class 1BIIIa.Conclusions Alteration of spray drying process variables, particularly solvent com-position and feed concentration can have a significant effect on the morphology ofspray dried microparticulate products. Morphology of spray dried particles may beusefully described using the morphology classification system. / The Irish Research Council for Science and Engineering Technology (IRCSET), the Solid State Pharmaceutical Cluster (SSPC), supported by Science Foundation Ireland under grant number [07/SRC/B1158] and the Irish Drug Delivery Research Network, a Strategic Research Cluster grant (07/SRC/B1154) under the National Development Plan co-funded by EU Structural Funds and Science Foundation Ireland.

Yes / High-dose API powders which are to be tableted by direct compression should have high compactibility and compressibility. This note reports on a novel approach to the manufacture of crystalline powders intended for direct compaction with improved compactibility and compressibility properties. The poorly compactable API, chlorothiazide, was spray dried from a water/acetone solvent mix producing additive-free nanocrystalline microparticles (NCMPs) of median particle size 3.5 μm. Tablets compacted from NCMPs had tensile strengths ranging from 0.5 to 4.6 MPa (compared to 0.6–0.9 MPa for tablets of micronised CTZ) at compression forces ranging from 6 kN to 13 kN. NCMP tablets also had high porosities (34–20%) and large specific surface areas (4.4–4.8 m2/g). The time taken for tablets made of NCMPs to erode was not statistically longer (p > 0.05) than for tablets made of micronised CTZ. Fragmentation of NCMPs on compression was observed. The volume fraction of particles below 1 μm present in the suspension recovered after erosion of NCMP tablets was 34.8 ± 3.43%, while no nanosized particles were detected in the slurry after erosion of compacted micronised CTZ. / Solid State Pharmaceutical Cluster (SSPC), supported by Science Foundation Ireland under grant number 07/SRC/B1158.

L’objectif de ces travaux de thèse visait une meilleure compréhension et représentation de lapropagation de la houle à travers les milieux poreux afin de proposer une nouvelle caractérisation desouvrages de défense du littoral. L’influence du paramètre de surface spécifique des milieux poreux (surfacede contact fluide-solide), à porosité constante, est mise en évidence sur des écoulements permanents etoscillants forcés par la houle à l’aide de séries d’expériences réalisées en canal et bassin d’essai. Les donnéesexpérimentales obtenues sont comparées à des modèles théoriques basés sur la théorie potentielle des ondeset résolus à travers des méthodes intégrales de raccordement des potentiels aux frontières entre domaines.Les processus de réflexion, transmission et dissipation sont étudiés dans le cas bidimensionnel, les processusde réflexion, réfraction-diffraction et dissipation de la houle sont étudiés dans le cas tridimensionnel. Desphénomènes d’interférence des ondes sont mis en évidence en observant le caractère oscillant du coefficient deréflexion en fonction de la fréquence de la houle dans le cas 2D. A ce processus d’interférences dans la directionde propagation de la houle dans le cas 2D s’ajoute, dans le cas 3D, un phénomène d’interférences dans ladirection transversale à la direction de propagation de la houle. Un comportement linéaire ou quadratique dutaux de dissipation de l’onde à l’intérieur du milieu poreux est observé. Le rôle de la surface spécifique dans ladissipation de l’énergie de l’onde à travers le milieu poreux est mis en évidence. Les régimes d’écoulement etles effets d’échelle sont également discutés. / The purpose of this Ph-D work aims to enhance knowledge and better describe wave propagationthrough porous media in order to propose a new characterization of coastal defense structures. The influenceof the specific surface parameter (fluid-solid contact surface) of porous media is then highlighted at givenporosity for steady and oscillatory wave induced flows with experiment series carried out in either wave tankor basin. Experimental data are compared with theoretical models based on wave potential theory numericalsolved by use of integral matching method at the domains’ boundaries.Wave scattering in the presence of porous structure is studied in both 2D and 3D cases. Interference processwithin the porous media are observed in the 2D case, leading to an oscillatory behavior of the reflection versusfrequency. Additional interference processes are observed in the transverse direction in the 3D case, leadingto a wave behavior strongly dependent on wave dynamics at both sides of the porous structure for resonantcases. Either linear or quadratic behavior of the dissipation is observed within the porous media. The role ofthe specific surface in the dissipation process is demonstrated. Both flow regimes and scale effects are alsodiscussed.

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