No description available.

No description available.

A study of the quenching abilities of a series of compounds containing heavy atoms was undertaken to ascertain whether or not 0₂(¹Σ⁺[formula omitted]) quenching is subject to heavy atom enhancement. Presence of a heavy atom effect would suggest significant quenching via the 0₂(¹Σ⁺[formula omitted] → ³Σˉ[formula omitted]) transition. The fact that no such effect is observed supports the generally assumed quenching mode: 0₂(¹Σ⁺[formula omitted] → ¹Δ[formula omitted]). A systematic investigation of the use of overlap of absorption spectrum of quencher with emission spectrum of 0₂(¹Σ⁺[formula omitted]) to obtain calculated quenching rate constants was undertaken. The correlation between calculated and experimental rate constants are examined and shortcomings of the method are presented. / Science, Faculty of / Chemistry, Department of / Graduate

M.Sc. (Physics) / The differential cross-section for p(e, e¡ä¦Ø)p has been studied at Q2 ¡« 5.5 (GeV/c)2. Here Q2 represents the four momentum squared of the virtual photon in the excitation of baryonic resonances by an electron projectile. The excitation cross-section for the baryonic resonances and their de-excitation rates and channels provides information on the underlying structure of QCD. The selection of the ¦Ø decay channel constrains the particular baryonic resonances that contribute to the measured cross-section. A significant aspect of the data presented from W = 1.72 GeV to W = 1.92 GeV is that the Q2 falls in the region where the transition from non-pertubative processes characterised by constituent quarks dominate to the regime where the hard processes are expected to play an increasing important role. This is therefore an interesting region to acquire further data. In order to extract the ¦Ø-meson differential cross section from the JLAB data, the data was compared to a full Monte Carlo simulation of the detector based on events generated for omega production in a way that the production cross section was varied to achieve a match to the data. The binning selected for this procedure takes into account the measure of robustness of the stripping of the ¦Ø peak from the multi-pion background as well as the statistics in the measured data and the Monte Carlo simulation of the signal and background physics [1]. An error estimation technique for the cross section was based on determining the dependence via the Monte Carlo simulation of the extracted cross section parameters on the experimental set-up (including parameters for the spectrometer, target beam geometries and performance). We compare our results with a Regge-based model for hadronic content in the t-channel exchange of a photon in Q2 region of overlap. There is an extension of this data into a completely new region, which is the highest yet measured. The result from the study of baryonic excitation via the ¦Ø channel gives a good correlation between theory and experiment in the overlapped kinematic regime of the used theoretical simulation.

No description available.

No description available.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Les machines électriques classiques comme les machines asynchrones et les machines à aimant permanent sont largement utilisées dans ces applications de traction, et surtout en traction ferroviaire. Cette thèse évalue la contribution d'un autre type de machines, appelé machines synchrones à double excitation dans cette même application. Le terme double excitation signifie que le flux de la machine est créé par deux sources : le bobinage d'excitation et les aimants permanents. Le degré de liberté fourni par le bobinage d'excitation permet d’atteindre l’objectif d’amélioration de l’efficacité. Ce travail a pour but d’identifier les avantages des machines à double excitation sur un cycle de conduite spécifique. Il définira également les cas dans lesquels cette machine fournira de meilleures performances que celles des machines classiques.Les études récentes considèrent uniquement l’optimisation des systèmes en optimisant chaque composant du système séparément. Cependant, avoir les meilleurs performances dans chacun de ces composants ne signifie pas avoir un meilleur système. Afin d'atteindre des résultats plus réalistes, un modèle multi-physique prenant en compte la non linéarité des matériaux sera développé. Ce modèle intègre également les différents aspects comme l’électromagnétisme, la thermique, la mécanique et l’électronique de puissance. / Classical electrical machines such as asynchronous and permanent magnet synchronous machines have been widely applied in traction applications and particularly in railway traction. This thesis, however, evaluate the contribution of a special class of synchronous machine called textbf{D}ouble textbf{E}xcitation textbf{S}ynchronous textbf{M}achine (DESM) for the railway traction. Double excitation term indicates that the field flux of the machine is created by two sources: excitation windings and permanent magnets. The degree of freedom provided by the excitation windings provides the opportunity to work on the energy efficiency improvement target. This thesis will try to answer the question whether DESM is more advantageous over classical machines in a specific driving cycle and in addition, in which cases a DESM performs better.Recent studies have merely optimized the individual components, the major drawback of this approach is that the combination of the best individuals does not necessarily form a best system. In order to achieve more realistic results, a multi-physic models taking into account nonlinear characteristic and various disciplines such as electromagnetic, thermal, mechanical and power electronics will be developed.

No description available.

The purpose of this investigation was to analyze the gamma rays resulting from excitation of Cs133 by the inelastic scattering of 14 MeV neutrons and to determine the relative intensity of each gamma ray.