The Standard Model of particle physics has been very successful in predicting a wide range of phenomena and has so far been confirmed by all existing data to a very high precision. The work described in this thesis tests the limits of validity of the Standard Model (SM) in two areas believed to be sensitive to deviations from the theory: the observation of unpredicted particles and CP violation. The studies were performed within the framework of experiments at two hadron colliders, the future ATLAS detector scheduled for operation in 2007 at the Large Hadron Collider in Geneva and the currently running DØ experiment at the Tevatron in Chicago. The tau lepton’s distinctive signature is a useful tool in many new physics searches where it is present in the final state. As a first study in ATLAS a Monte Carlo analysis of two-tau final states, which are sensitive to the underlying structure of supersymmetric models, was performed. Several extensions of the SM predict the existence of a charged Higgs boson.The major part of this thesis has consisted in using tau leptons to search for the charged Higgs in the context of the Minimal Supersymmetric extension of the SM (MSSM). Results from this thesis show that searches for the H± → τντ decay channel extend the charged Higgs discovery reach for the ATLAS experiment compared to previous studies of other channels: the charged Higgs can be observed for masses up to ~ 600 GeV for tanβ > 10. Its mass can be determined with an uncertainty of 1 to 2%, dominated by statistical errors. The tanβ parameter can be derived from the absolute rate of this decay to a precision around 6% for 20 < tan β < 50. By measuring precisely the unitarity triangle parameter sin2β the SM description of CP violation can be put to a test. As a separate study a Monte Carlo analysis was performed in ATLAS, which shows that the systematic uncertainty is half the attainable statistical uncertainty. As part of the effort to search for the charged Higgs in the DØ experiment a trigger algorithm for tau leptons was written, extensively tested and implemented in the experiment. Trigger strategies for events containing taus were designed. These trigger studies will be useful also for many other new physics searches at DØ.

A search for cosmic point sources of neutrinos has been performed using data taken in 1999 with the AMANDA-B10 neutrino telescope. This work describes methods for signal and background separation and the statistical analysis of the final data sample. In particular, the multivariate method Support Vector Machines has been applied to achieve good background rejection while at the same time retaining high signal efficiency. A grid search covering the complete northern hemisphere revealed no statistical significant excess of events over the expected background from mis-reconstructed cosmic ray induced muons and muons induced by atmospheric neutrinos. Thus, no cosmic point sources of neutrinos have been detected. Upper limits on the neutrino flux for each cell of the grid are presented. Twenty potential sources of neutrinos chosen among three classes of astronomical objects (Blazars, Super Nova Remnants and Microquasars) have been preselected. Upper Limits on the flux of cosmic neutrinos from those are presented. The presence of systematic uncertainties makes the calculation of confidence limits an intricate problem. A method is presented which makes it possible to include these uncertainties into the frequentist construction of confidence intervals. Statistical properties of the presented method have been studied.

Avatime, a Kwa language of Ghana, has an additive particle tsyɛ that at first sight looks similar to additive particles such as too and also in English. However, on closer inspection, the Avatime particle behaves differently. Contrary to what is usually claimed about additive particles, tsyɛ does not only associate with focused elements. Moreover, unlike its English equivalents, tsyɛ does not come with a requirement of identity between the expressed proposition and an alternative. Instead, it indicates that the proposition it occurs in is similar to or compatible with a presupposed alternative proposition.

Approximately 80% of pharmaceutical products and the ingredients required for their manufacture are in powder form. The solid dosage form (tablets and capsules) is manufactured by either dry-blending of fine powder ingredients or combining the ingredients in a wet granulation step, followed by drying. Arching, ratholing, caking, segregation and flooding are some of the commonly encountered flow problems in the handling of fine powders. These problems lead to losses worth thousands of dollars at production scale. Poor powder flowability is a consequence of the combined effects of many variables, including improper equipment design, particle size, size distribution, shape, moisture content and surface texture. In the present work, a systematic study has been performed to determine the relationship between the flowability of fine powders and their physical properties of mean size and size distribution, density and shape.<p> Flowability studies were done on six different powders: the NutraSweet® Brand sweetener (aspartame), Respitose ML001, Alpha-D-Lactose monohydrate, the pharmaceutical binder Methocel (R) F50 Premium Hydroxypropyl methylcellulose- HPMC, a placebo pharmaceutical granulate, and common pastry flour. Scanning electron microscopy (SEM) and stereomicroscopy were used for particle shape and size analysis. Particle size distribution was determined using the laser light scattering technique. Powder flowability was measured using shear strength, angle of repose, and tapped-to-bulk density measurements. A novel method of measuring the dynamic angle of repose using electrical capacitance tomography (ECT) was developed. <p> Analysis of the images from microscopy revealed that the particles of aspartame and HPMC powders were elongated, the particles of ML001, pastry flour and lactose monohydrate powders were irregular, and the particles of placebo granulate were nearly spherical. Particle size was found to be the most reliable indicator of powder flowability, with decreasing particle size corresponding to lower flowability; however other parameters such as particle elongation and irregularity, were also found to have an influence on powder flowability. Although HPMC and pastry flour had similar particle sizes, they exhibited differences in flowability. This can be explained by the greater irregularity of the flour particles. Particle irregularity may cause mechanical interlocking between the particles, thus reducing powder flowability. ECT was found to be a promising non-intrusive tool for the measurement of the dynamic angle of repose. Unlike other methods for the measurement of dynamic angle of repose, the results obtained from ECT were not influenced by the effect of end caps. The present technique could be used by pharmaceutical industries in process analytical technology (PAT) for the detection and elimination of potential flow problems early in the manufacturing process.

Approximately 80% of pharmaceutical products and the ingredients required for their manufacture are in powder form. The solid dosage form (tablets and capsules) is manufactured by either dry-blending of fine powder ingredients or combining the ingredients in a wet granulation step, followed by drying. Arching, ratholing, caking, segregation and flooding are some of the commonly encountered flow problems in the handling of fine powders. These problems lead to losses worth thousands of dollars at production scale. Poor powder flowability is a consequence of the combined effects of many variables, including improper equipment design, particle size, size distribution, shape, moisture content and surface texture. In the present work, a systematic study has been performed to determine the relationship between the flowability of fine powders and their physical properties of mean size and size distribution, density and shape.<p> Flowability studies were done on six different powders: the NutraSweet® Brand sweetener (aspartame), Respitose ML001, Alpha-D-Lactose monohydrate, the pharmaceutical binder Methocel (R) F50 Premium Hydroxypropyl methylcellulose- HPMC, a placebo pharmaceutical granulate, and common pastry flour. Scanning electron microscopy (SEM) and stereomicroscopy were used for particle shape and size analysis. Particle size distribution was determined using the laser light scattering technique. Powder flowability was measured using shear strength, angle of repose, and tapped-to-bulk density measurements. A novel method of measuring the dynamic angle of repose using electrical capacitance tomography (ECT) was developed. <p> Analysis of the images from microscopy revealed that the particles of aspartame and HPMC powders were elongated, the particles of ML001, pastry flour and lactose monohydrate powders were irregular, and the particles of placebo granulate were nearly spherical. Particle size was found to be the most reliable indicator of powder flowability, with decreasing particle size corresponding to lower flowability; however other parameters such as particle elongation and irregularity, were also found to have an influence on powder flowability. Although HPMC and pastry flour had similar particle sizes, they exhibited differences in flowability. This can be explained by the greater irregularity of the flour particles. Particle irregularity may cause mechanical interlocking between the particles, thus reducing powder flowability. ECT was found to be a promising non-intrusive tool for the measurement of the dynamic angle of repose. Unlike other methods for the measurement of dynamic angle of repose, the results obtained from ECT were not influenced by the effect of end caps. The present technique could be used by pharmaceutical industries in process analytical technology (PAT) for the detection and elimination of potential flow problems early in the manufacturing process.

Particle size distribution (PSD) of gypseous soils is important in the soil science community. When gypsum constitutes a major portion of the soil, its removal prior to PSD analysis distorts the results and may lead to textures that do not relate to conditions in the field. In order to understand the true characterization of the soil and the gypsum particles, the entire soil sample should be analyzed. Four different approaches to the BaCl2 method presented in the literature (Hesse, 1976, Matar and Douleimy, 1978, Viellefon, 1979) were used to evaluate the use of BaCl2 solution to reduce the solubility of gypsum by forming a protective coating of BaSO4 around gypsum particles. Results showed that the BaCl2 method was unsatisfactory, as dispersion of clays was not sufficient to allow particle size analysis using the pipette method. A procedure using a laser diffraction particle size analyzer (LPSA) was also evaluated. As gypsum is insoluble in methanol, methanol was selected as a possible solution, but it caused flocculation of clays and could not be used to analyze samples containing silicate clays. Gypsum saturated water containing Na hexametaphosphate was evaluated as a solution. First, 20 non-gypseous samples were analyzed on a sand-free basis using saturated gypsum water with Na hexametaphosphate. Results were used to establish a relationship comparing LPSA results and pipette results. An equation y = 1.37x + 2.03 was established relating LPSA clay percent by volume (x) to the pipette clay percent by weight (y). The equation had a R2 value of 0.84 and was significant at the 1% level. From this equation a comparison of 21 gypseous samples was made, between clay percentages of the pipette method and the LPSA method. Results indicate that LPSA can be used to give a satisfactory particle size distribution of gypseous soils when coupled with sand analysis by sieving.

Submarine canyons are common features on continental margins worldwide. They are important natural conduits for transfer of terrigenous sediments to the deep sea, and thus, preferential pathways for shelf-slope exchange. The purpose of this study is to understand the biogenic particle transport in the seasons according two sediment trap moorings deployed in the Gaoping submarine canyon. The T6KP mooring was deployed in dry season while the T7KP mooring was deployed in wet season. Two typhoons, Kalmaegi and Fung Wong, invaded Taiwan during 16-18 and 26-29 July within the deployment of T7KP. We discussed the influence of rainfall and river discharge on biogenic particle transport based on results of the two sediment traps. The foraminiferal abundance in sediment traps in comparison with plankton tows was discussed regarding the particle transport mechanism of the water column in the Gaoping submarine canyon. The biogenic particle transport was a tide-dominated situation and displayed a periodic variation in dry season. In wet season, fine grain fraction (less than 63 micro meter) was dominant in the particle size and sedimentary condition was flood-dominated. The sedimentary condition was back to the tide-dominated state approximately 15 days after Kalmaegi typhoon (16-18, July). The activities of 210Pb and 234Th in the lower trap of T7KP mooring were an order less than that in T6KP mooring, indicating particles scavenge nuclides of the water column less effectively in wet season than in dry season. The absolute abundances of foraminifera in the canyon revealed that the biogenic particle was influenced by the terrigenous input and was different between dry and wet seasons. Seasonal variations of total flux and relative abundance of living foraminifera were evident in the upper 200 m water column near the Gaoping submarine canyon. Therefore, the seasonal variations of living foraminifera might be reflected on the biogenic particle transport in different seasons in the Gaoping submarine canyon.

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 111-116).

The physico-chemical characteristics of soymilk particles and the gelation properties of soymilk were investigated as a function of soymilk protein concentration, by preparing soymilk samples from different water-to-bean ratios. Particles from different soymilk protein concentrations showed similar protein composition and surface hydrophobicity, but different -potential, size and protein content. The particle voluminosity was derived using a relation between the effective refractive index of soymilk and the turbidity parameter determined experimentally. For the first time, experimental data was compared to theoretical models, drawing general conclusions about colloidal properties of soymilk particles. Protein concentration and the rate of acidification did not have a significant effect on the acid-induced gelation of soymilk. Results demonstrated that decreased charge is a prerequisite for particle aggregation, which is driven by hydrogen bridging. This thesis provides soymilk processors with general principles on the colloidal behaviour of soymilk, valuable information for new product development and better process design. / Soybean Growers of Ontario, Natural Sciences and Engineering Research Council of Canada

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