Cu(In,Ga)Se2 (CIGS) is one of the most promising semiconductor compounds for large-scale production of efficient, low-cost thin film solar cells, and several research institutes have announced their plans for CIGS production lines. But for the CIGS technology to become a commercial success, a number of issues concerning manufacturability, product definition, and long-term stability require further attention. Several studies indicate that CIGS-based modules are stable over many years in field operation. At the same time, it is shown in the present work that they may have difficulties in passing standard accelerated lifetime test procedures like the IEC 1646 damp heat test. In particular, CIGS modules are sensitive to humidity penetrating through the module encapsulation, which will increase the resistive losses in the front contact and cause severe corrosion of the back contact. It is also shown that cells experience degradation in both voltage and fill factor, and the causes of these effects are addressed. By concentrating the light falling onto a solar cell, the device will deliver a higher power output per illuminated absorber area, which can lower the electricity production costs. For CIGS-based solar cells, low-concentrated illumination could be an economically viable approach. In this work it is shown that the yearly performance of a photovoltaic system with CIGS modules can be significantly improved at a moderate cost by using parabolic aluminum mirrors as concentrating elements. However, in order to avoid detrimental power losses due to high temperatures and current densities, the modules need to be designed for the higher light intensity and to be sufficiently cooled during operation. A design where the front contact of the module is assisted by a metal grid has shown promising results, not only for concentrated illumination but also for normal operation. The benefits are enhanced window processing tolerance and throughput, as well as improved degrees of freedom of the module geometry.

The diesel engine is growing in popularity due to its energy efficiency and solving the emissions issues associated with diesel engine exhaust would clear the way for further growth. The key pollutants are NOx, particulate matter and unburned hydrocarbons. Selective catalytic reduction (SCR) catalysis is likely the best choice for NOx control. In SCR, NH3 selectively reacts with NOx to form N2 – the selectivity refers to NH3 reacting with NOx instead of the abundant O2. Urea is used as the NH3 source, being injected into the exhaust as an aqueous solution where the urea decomposes and NH3 is generated. Spatial resolution characterization techniques have been gaining attention in the catalysis field because of the higher level of information provided. In this thesis, a new spatial resolution technique, called SpaciFTIR (spatially-resolved, capillary-inlet Fourier transform infra-red spectroscopy), was developed, which overcomes the interference of water in the detection of NH3 in an earlier developed technique, SpaciMS (spatially-resolved, capillary-inlet mass spectrometry). With the new test method, three SCR topics were addressed. First, the three key SCR reactions were spatially resolved. These are the standard SCR reaction (2NO + 2NH3 + 1/2O2 = 2N2 + 3H2O), the fast SCR reaction (NO + NO2 + 2NH3 = 2N2 + 3H2O), and NO2-SCR, (6NO2 + 8NH3 = 7N2 + 12H2O). Results show that in the presence of NO2, but at a NO2/NOx ratio < 0.5, the fast SCR reaction proceeds followed by the standard SCR reaction, i.e. in series. If the NO2/NOx ratio exceeds 0.5, the NO2-SCR and fast SCR reactions occur in parallel. Compared to the standard integral test method, this spatial resolution technique clearly showed such trends. Secondly, the spatial resolution technique was used to characterize the effects of thermal aging on catalyst performance. It was found that for a highly aged catalyst, there was a radial activity profile due to an inhomogeneous temperature distribution in the process of aging. Aging effects on various key SCR reactions, i.e. NO oxidation, NH3 oxidation, and the reduction reactions, were studied. Last but not least, for the purpose of passive SCR system development, transient NH3 storage profiles along the monolith channel were measured with SpaciFTIR. Passive SCR is a system where the NH3 is generated on an upstream catalyst, such as a three-way catalyst or lean-NOx trap, instead of via urea injection. In such a system, NH3 is therefore not constantly being fed to the SCR catalyst, but “arrives” in pulses. Factors such temperature, NH3 concentration, pulsing time, flow rate and thermal aging were investigated. For the first time, NH3 migration was observed and its effect on SCR reactions along the length of catalyst was studied.

Les alliages aluminium-cuivre, et en particulier l'alliage 2024 (4% de Cu) sont utilisés dans l'industrie aéronautique pour leur faible densité alliée à de très bonnes propriétés mécaniques. Néanmoins, ces alliages sont très sensibles à la corrosion. Ainsi dans le cas de l'alliage 2024, la présence de précipités riches en cuivre, noyés dans une matrice d'aluminium, soumet cet alliage à un risque de corrosion galvanique. Dans une solution en plein bain contenant un électrolyte aéré de pH neutre, le couplage galvanique entre les deux métaux se produit comme prévu : la dissolution d'aluminium est la réaction anodique et la réduction de l'oxygène est la réaction cathodique à la surface du cuivre. La formation d'une crevasse à l'interface Al / Cu, avec re-déposition de cuivre dans le voisinage de l'interface a souvent été observée, mais n'a jamais été clairement expliquée. Ainsi, le but de ce travail est de mettre en évidence le mécanisme de dissolution du cuivre et de voir l'influence du confinement sur ce comportement. Un montage en couche mince a été mis au point au laboratoire, permettant d'obtenir une couche d'électrolyte (d'épaisseur inférieure à quelques centaines de micromètres) entre deux plans parallèles contenant respectivement des électrodes en cuivre pur et en aluminium pur. Le courant et le potentiel galvaniques ont été suivis en fonction du temps, de la distance entre les deux métaux, ainsi que du rapport des surfaces variant entre 10 et 0,1 entre le cuivre et l'aluminium. Après le remplacement de l'électrode supérieure par une paroi isolante, le comportement de l'électrode de cuivre a été suivi en présence d'ions Al3+ dans la couche mince. Enfin, le mécanisme de couplage galvanique est discuté en tenant compte de la modification du pH au sein de la couche mince d'électrolyte.

The West Ansil deposit was the first Cu discovery in 25 years in the Noranda Central Camp. It has a combined indicated and inferred resource of ~1.2 Mt. Grades for the indicated resource are 3.4% Cu, 0.4% Zn, 1.4 g/t Au and 9.2 g/t Ag. The bulk of the resource is located in three massive sulphide lenses (Upper, Middle and Lower) that are entirely within the Rusty Ridge Formation above the Lewis exhalite. The mineralization in all three ore lenses consists of massive pyrrhotite + chalcopyrite + magnetite. Semi-massive sphalerite is restricted to the upper and lower parts of the Middle lens. Massive magnetite occurs at the center of the Upper and Middle lenses, where it replaces massive pyrrhotite. A striking feature of West Ansil is the presence of abundant colloform and nodular pyrite (+marcasite) in the massive sulphides. Late-stage replacement of massive pyrrhotite by colloform pyrite and marcasite, occurs mostly along the upper and lower contacts of the lenses.

Nuclear-based hydrogen production via thermochemical water decomposition using a copper-chlorine cycle consists of a series of chemical reactions that split water into hydrogen and oxygen. This is accomplished through reactions involving intermediate copper and chlorine compounds, which act as catalysts that are recycled in the process. In this thesis, analytical and numerical solutions are developed to predict the behaviour of aqueous cupric chloride droplets in a solution undergoing spray-drying in the Cu-Cl cycle. The aqueous CuCl2 is present as a slurry within the cycle, which will later generate oxygen and hydrogen as a net result. The efficiency of the cycle can be increased by utilizing low-grade waste heat from any industrial source or nuclear power plant to assist in the drying process. There are many different methods employed in industry for drying of solutions. Each method has its own advantages and disadvantages, depending on the application and conditions. In this thesis, analytical correlations of heat and mass transfer are developed for the aqueous solution, subject to various drying conditions. The analysis is performed for moist air in contact with a sprayed aqueous solution of CuCl2(2H2O). Validation of the model is performed by comparisons with experimental results obtained from a Niro-spray dryer for CuCl2 and previous experimental and theoretical data for different fluids, on the basis of non-dimensional analysis. / UOIT

The use of communication networks in digital control systems introduces stability and reliability concerns. Standard reliability and safety assessment methods need further modification to accommodate the issue in the reliability assessment of networked control systems. In this thesis, it is demonstrated that the Dynamic Flowgraph Methodology (DFM) can be extended to model networked control systems. The modelling of the communication network influence on the performance of the control system is presented. The areas that can affect the reliability of the control system are identified using the methodology. The thesis also presents the application of the DFM to a nuclear-based thermochemical water splitting process for hydrogen production, the Copper-Chlorine (Cu-Cl) cycle. The architecture of a networked control system and configuration of instrumentation and control systems for the hydrogen production plant are proposed in the thesis. / UOIT

Two methods for refining metallurgical grade silicon to solar grade silicon have been investigated. The first method involved the reduction of impurities from metallurgical grade silicon by high temperature vacuum refining. The concentrations of analyzed elements were reduced several times. The main steps in the second refining method include alloying with copper, solidification, grinding and heavy media separation. A metallographic study of the Si-Cu alloy showed the presence of only two microconstituents, mainly pure silicon dendrites and the Cu3Si intermetallic. SEM analysis showed a distinct boundary between the silicon and the Cu3Si phases, with a large concentration of microcracks along the boundary, which allowed for efficient separation. After alloying and grinding, a heavy media liquid was used to separate the light silicon phase from the heavier Cu3Si phase. Cu3Si residues together with the remaining impurities were found to be located at the surface of the pure silicon particles, and should be efficiently removed by acid leaching. Thirty elements were analyzed by the Inductively Coupled Plasma Mass Spectrometry (ICP) chemical analysis technique. ICP revealed a several times higher impurity level in the Cu3Si intermetallic than in the pure silicon; furthermore, the amounts of 22 elements in the refined silicon were reduced below the detection limit where the concentrations of 7 elements were below 1ppmw and 6 elements were below 2ppmw. The results showed that the suggested method is efficient in removing impurities from metallurgical grade silicon with great potential for further development.

Two methods for refining metallurgical grade silicon to solar grade silicon have been investigated. The first method involved the reduction of impurities from metallurgical grade silicon by high temperature vacuum refining. The concentrations of analyzed elements were reduced several times. The main steps in the second refining method include alloying with copper, solidification, grinding and heavy media separation. A metallographic study of the Si-Cu alloy showed the presence of only two microconstituents, mainly pure silicon dendrites and the Cu3Si intermetallic. SEM analysis showed a distinct boundary between the silicon and the Cu3Si phases, with a large concentration of microcracks along the boundary, which allowed for efficient separation. After alloying and grinding, a heavy media liquid was used to separate the light silicon phase from the heavier Cu3Si phase. Cu3Si residues together with the remaining impurities were found to be located at the surface of the pure silicon particles, and should be efficiently removed by acid leaching. Thirty elements were analyzed by the Inductively Coupled Plasma Mass Spectrometry (ICP) chemical analysis technique. ICP revealed a several times higher impurity level in the Cu3Si intermetallic than in the pure silicon; furthermore, the amounts of 22 elements in the refined silicon were reduced below the detection limit where the concentrations of 7 elements were below 1ppmw and 6 elements were below 2ppmw. The results showed that the suggested method is efficient in removing impurities from metallurgical grade silicon with great potential for further development.

The West Ansil deposit was the first Cu discovery in 25 years in the Noranda Central Camp. It has a combined indicated and inferred resource of ~1.2 Mt. Grades for the indicated resource are 3.4% Cu, 0.4% Zn, 1.4 g/t Au and 9.2 g/t Ag. The bulk of the resource is located in three massive sulphide lenses (Upper, Middle and Lower) that are entirely within the Rusty Ridge Formation above the Lewis exhalite. The mineralization in all three ore lenses consists of massive pyrrhotite + chalcopyrite + magnetite. Semi-massive sphalerite is restricted to the upper and lower parts of the Middle lens. Massive magnetite occurs at the center of the Upper and Middle lenses, where it replaces massive pyrrhotite. A striking feature of West Ansil is the presence of abundant colloform and nodular pyrite (+marcasite) in the massive sulphides. Late-stage replacement of massive pyrrhotite by colloform pyrite and marcasite, occurs mostly along the upper and lower contacts of the lenses.

The Bird River sill (BRS) is composed of layered mafic-ultramafic intrusive bodies which intruded the Bird River greenstone belt in southeastern Manitoba. Layered intrusions, such as those that collectively make-up the BRS, are important hosts to base and precious metal deposits. This study was initiated to examine and develop an emplacement model for the western half of the BRS and to establish the controls on Cr-Ni-Cu-PGE mineralization. The BRS intrusions were emplaced through multiple-magmatic injections into different stratigraphic levels in the Lamprey Falls Formation. It is interpreted that the central BRS intrusions are connected and represent a single conduit system. The BRS and the Lamprey Falls Formation are overlain by the metasedimentary rocks of the Peterson Creek Formation and are overturned. The stratigraphy of the BRS is divided into four series which are from the base upwards: 1) marginal mafic series, 2) ultramafic series, 3) transition series, and 4) mafic series. All significant concentrations of Cr-Ni-Cu-PGE are contained in the ultramafic series. Mineralization is magmatic in origin with significant Ni-Cu and PGE remobilization associated with late felsic magmatism. Ni-Cu remobilization is also associated with mineralized shear zones that cross-cut the BRS and Lamprey Falls Formation. The sulphur source could not be determined unambiguously based on sulphur isotopes alone but the δ34S values of the BRS intrusions suggests that the sulphur in the BRS is magmatic in origin and that two of the BRS bodies may have assimilated external sulphur. The findings of this investigation have considerable economic implications. The model that each BRS body is an individual intrusion implies each body may contain its own style of mineralization. Secondly, the Page body of the BRS is interpreted to represent a turbulent magmatic environment and to be the first intrusion to form at the lowest stratigraphic level. The magmas that formed the stratigraphically higher BRS intrusions are believed to have passed through the Page intrusion. Therefore, the Page body is an excellent exploration target as it represents a turbulent environment in which significant amounts of primitive magma have passed through which are two key factors in the formation of Ni-Cu-PGE deposits.