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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Portable science: podcasting as an outreach tool for a large academic science and engineering library

Barsky, Eugene, Greenwood, Aleteia, Lindstrom, Kevin 02 July 2009 (has links)
INTRODUCTION While the concept is widely defined and interpreted, all Web 2.0 tools have certain characteristics in common; they are collaborative in nature, interactive, and dynamic. The Science and Engineering librarians at the University of British Columbia are collaborating with their liaison departments to record science and engineering podcasts, host them and share them with a wider audience. OBJECTIVES In this session, we discuss the use of podcasting as an outreach tool that connects a large academic science and engineering library with its users and raises users’ awareness of additional library services. Functionality, usability and practical applications of podcasting tools are reviewed. OUTCOMES At the end of this session, we will have demonstrated: 1) Overall usability of podcasting academic science and engineering content; tips and tricks when creating and tailoring podcasts to your community needs; 2) Use of podcasting as an outreach and community engagement tool in academic libraries and as a supplement for the traditional academic information resources. DISCUSSION The strength of podcasting, to allow content to be created by the users for the users, makes it an appealing addition to the academic librarians’ toolbox. Podcasting is a service that many of our users might not expect from their library, which makes it a unique and attractive offering. It requires few resources, and the end result might exceed librarians’ expectations. We found podcasting to be a robust outreach tool and a service that raises the profile of the library and as such creates an opportunity for users to find additional library resources. Nevertheless, it is necessary for academic librarians to critically evaluate the continuous innovations of Web 2.0 technologies on an ongoing basis so that they are best prepared to put them into the appropriate context amongst other relevant and important information.
72

Altération et minéralisation d'uranium à Shea Creek (Ouest Athabasca, Saskatchewan, Canada) : vers un nouveau modèle génétique de gisement / Clay alteration and uranium mineralization in the Shea Creek area in the Athabasca basin, Saskatchewan, Canada : toward a new model of genesis of unconformity related uranium deposits

Uri, Freddy 13 December 2012 (has links)
Shea Creek est un gisement d'uranium liée à la discordance entre un socle métamorphique et des roches sédimentaires d'origine fluviatile, d'âge Paléo-protérozoïque et situé dans la partie ouest du bassin d'Athabasca. Ce gisement majeur est le plus profond connu actuellement dans le bassin (entre 680 m et 1000 m de profondeur). Il rassemble en un même lieu tous les types de minéralisation associés à une discordance connus de par le monde. Cette étude s'appuie sur l'analyse de plus de 1200 échantillons du halo d'altération qui entoure le gisement et sur l'utilisation des données d'exploration minière. L'objectif est double. Il s'agit d'une part de déterminer des guides sédimentologiques, pétrographiques, minéralogiques et géochimiques pour la prospection des corps minéralisés en zone profonde et d'autre part d'utiliser ces critères pour construire une représentation tridimensionnelle simplifiée (minéralisation et halo d'altération) permettant de préciser le modèle génétique de ce gisement profond. La localisation des différentes zones minéralisées dépend non seulement des phénomènes d'altération liés aux circulations hydrothermales contrôlées par la tectonique, mais aussi de la nature du remplissage sédimentaire et de son évolution diagénétique. L'architecture de la zone minéralisée de Shea Creek montre que les corps minéralisés sont localisés dans des structures en grabben remplies par des alternances de grès propres et de grès argileux souvent préservés de la compaction et de l'altération. La signature minéralogique et géochimique de ces grès suggère un apport provenant de l'érosion de paléo-altérites continentales (régolithe). La très forte concentration en défauts d'ir / Shea Creek is an unconformity-type uranium deposit located in the west part of Atabaska basin. It is related to an unconformity between a metamorphic basement and sedimentary rocks of fluvial origin, of paleoproterozoic age. Shea Creek's particularity is to be the deepest ore deposit ever known in the basin (between 680 m and 1000 m deep). It gathers all types of unconformity hosted mineralization known. More than 1200 samples, taken from halo alteration around the deposit, were analyzed and mining exploration data were used for this study. First, the aim was to determine the markers for prospection of mineral elements in deep area: sedimentological, petrographical, geochemical and mineralogical types. Then, it was to build a simple three-dimensional model (mineralization and alteration halo) using these criteria in order to precise the genetic pattern of this deep deposit. The location of mineralized areas depends on tectonic deformation, on sedimentary filling and diagenetic development. The morphology of Shea Creek’s ore deposit shows clearly that mineralization is located in the grabbens composed by clean sandstones and clay sandstones, often preserved from compaction and alteration phenomena. The mineralogical and geochemical signature of these clay sandstones suggests a contribution from the erosion of continental paleo-alterite (regolith). Beside, the great concentration of radiation induced defects suggests the presence in abundance of uranium in the grabbens from sedimentary state.
73

Toxicokinetics and Bioaccumulation of Polycyclic Aromatic Compounds in Wood Frog Tadpoles (Lithobates sylvaticus) Exposed to Athabasca Oil Sands Sediment

Bilodeau, Julie January 2017 (has links)
Many polycyclic aromatic compounds (PACs) are toxic, carcinogenic, and mutagenic. As a result, their effects on aquatic biota and ecosystems are of great concern. Research on PACs in aquatic biota often overlooks the role of amphibians, alkylated PACs, and sediment as an uptake route. In order to study the accumulation and toxicokinetics of PACs following sediment and aqueous exposure, and to compare the bioaccumulation potentials of parent and alkyl PACs, two accumulation-elimination experiments using wood frog tadpoles (Lithobates sylvaticus) of Gosner stage 28-32 were conducted (one evaluating exposure to contaminated sediment and water, and the other to contaminated water alone). A complementary field study was then conducted near Fort McMurray, Alberta to assess PAC body burdens in field-collected amphibian larvae, and to determine whether PAC body burdens are related to exposure to sediment and/or water in the field. The results of our studies showed that PAC concentrations and uptake rates in wood frog tadpoles were highest when they were exposed to PAC-contaminated sediment. Consequently, we determined that the dominant route of exposure of wood frog tadpoles to PACs is sediment rather than water. This finding supports other studies that have shown dietary uptake to be an important route of PAC exposure in other aquatic organisms. In both the laboratory and field study, alkyl PAC concentrations exceeded those of parent PACs in wood frog tadpoles, which also demonstrated petrogenic PAC profiles. Interestingly, parent PACs seemed to have greater bioaccumulation potential than alkyl PACs in the laboratory-exposed wood frog tadpoles (in relation to sediment), possibly due to greater bioavailability or lower metabolism of parent PACs or alternatively, due to a saturation in uptake of alkyl PACs. Nevertheless, only a few compounds, including anthracene, fluoranthene, retene, and C1-benzofluoranthenes/benzopyrenes, were found to have higher bioaccumulation potentials. Lithobates sylvaticus tadpoles seemed to be efficient at eliminating and metabolizing both parent and alkyl PACs. However, the elimination of some compounds, such as C4-naphthalenes, was not as efficient. Furthermore, C3-fluorenes and C2-dibenzothiophenes were isolated as potential markers of amphibian larvae exposure to PAC-contaminated sediment due to their positive correlation with the wetland sediment concentrations. Additional field collections in the Athabasca oil sands are warranted to verify the utility of these markers in the natural environment. Evidently, this thesis highlights the importance of including sediment exposure and alkylated PACs in toxicological and field studies of benthic and epibenthic organisms. The results of this study are the largest, most comprehensive set of toxicokinetic and bioaccumulation information of PACs (52 analytes) in the amphibian larvae Lithobates sylvaticus obtained to date.
74

Geovisualization of boreal peatland architecture in a three dimensional hydrogeological framework using ground penetrating radar and LiDAR at Mariana Lakes, Alberta, Canada

Shulba, William Paul 07 June 2021 (has links)
Communicating science in three-dimensional (3D) multimedia is an immersive and interactive way to explore scientific processes (Signals and Communication Technology, 2019). Geovisualization is an emerging 3D multimedia method for visual analysis, synthesis, and presentation of geospatial, geologic, and geophysical data (MacEachren & Kraak, 2001). There is an identified need to develop scientific communication tools to further understand boreal peatland evolution, hydrogeology, ecology, and geochemistry (Bubier et al., 2003) since the International Union of Conservation of Nature asserts that peatlands are among the most valuable ecosystems on Earth, critical for preserving global biodiversity, providing drinking water, minimising flood risk, preventing wildfire, and mitigating climate change (Hama et al., 2000). The intention of this thesis is to communicate a novel approach to geovisualize boreal peatland architecture using Light Detection and Ranging (LiDAR) and Ground Penetrating Radar (GPR). GPR and LiDAR have been used to create 3D subsurface geovisualizations for archaeology (Kenady et al., 2018; Schultz & Martin, 2011) and resource geology (Corradini et al., 2020; Koyan & Tronicke, 2020) although application to peatland hydrogeology is uncommon. Point-source hydrogeological and geochemical data were integrated with 3D geological models to estimate carbon and nitrogen storage in an archetypal boreal peatland near Mariana Lakes, Alberta. Peatland geometry resembled a shallow lake basin with depths greatest in fens (>10 m) and thinnest in bogs (<2 m). Hydraulic conductivity was only a few meters per year and vertical groundwater movement was limited. Sequestered carbon and nutrients increased with depth. The average concentration of dissolved ammonium was 3 grams per cubic metre of peat (g/m3), 5g/m3of Total Kjeldahl Nitrogen, 60g/m3 of dissolved organic carbon and 200g/m3 of dissolved inorganic carbon. Tritium detection from atmospheric atomic weapons radionuclide fallout revealed that in deeper anaerobic peat (catotelm), tritium was absent, signifying groundwater was older than 50 years and not mixed with meteoric waters. Fen catotelm channels are likely acting as gravity-driven hydraulic traps (Tóth, 1999). / Graduate
75

Udržitelný rozvoj v Kanadě ve vztahu k těžbě ropných písků / Sustainable Development in Canada in Relation to Oil Sands Developments

Podhola, Adam January 2013 (has links)
The aim of this thesis is to evaluate to what extent Canada and Alberta have been fulfilling the principles of sustainable development as they have adopted in the 1990s from the essential U.N. documents - the Brundtland Report and the Rio Declaration- and to what extent both governments failed in providing and enforcing efficient environmental law protection as it is the basic premise for achieving sustainability. I assessed this level of sustainability in Canada and Alberta on the basis of a stronger and weaker sustainability theoretical framework. Author's presumption was that Canada, as it defined sustainable development in its legislation, acted according to stronger sustainability, which emphasizes stronger protective environmental measures. Given a very large scope of environmental impacts of oil extraction on different ecosystems, the sector of water resources was selected to serve as a case study to compare and analyze government and alternative reports assessing the sustainability of water management. Thus, the author follows how the oil industry in Alberta affects the water resources and how both governments of Canada and Alberta provide environmental protection to the water resources. In this respect the author illustrates how the government is reluctant towards the implementation of...
76

Integration and Simulation of a Bitumen Upgrading Facility and an IGCC Process with Carbon Capture

El Gemayel, Gemayel 19 September 2012 (has links)
Hydrocracking and hydrotreating are bitumen upgrading technologies designed to enhance fuel quality by decreasing its density, viscosity, boiling point and heteroatom content via hydrogen addition. The aim of this thesis is to model and simulate an upgrading and integrated gasification combined cycle then to evaluate the feasibility of integrating slurry hydrocracking, trickle-bed hydrotreating and residue gasification using the Aspen HYSYS® simulation software. The close-coupling of the bitumen upgrading facilities with gasification should lead to a hydrogen, steam and power self-sufficient upgrading facility with CO2 capture. Hydrocracker residue is first withdrawn from a 100,000 BPD Athabasca bitumen upgrading facility, characterized via ultimate analysis and then fed to a gasification unit where it produces hydrogen that is partially recycled to the hydrocracker and hydrotreaters and partially burned for power production in a high hydrogen combined cycle unit. The integrated design is simulated for a base case of 90% carbon capture utilizing a monoethanolamine (MEA) solvent, and compared to 65% and no carbon capture scenarios. The hydrogen production of the gasification process is evaluated in terms of hydrocracker residue and auxiliary petroleum coke feeds. The power production is determined for various carbon capture cases and for an optimal hydrocracking operation. Hence, the feasibility of the integration of the upgrading process and the IGCC resides in meeting the hydrogen demand of the upgrading facility while producing enough steam and electricity for a power and energy self-sufficient operation, regardless of the extent of carbon capture.
77

Integration and Simulation of a Bitumen Upgrading Facility and an IGCC Process with Carbon Capture

El Gemayel, Gemayel 19 September 2012 (has links)
Hydrocracking and hydrotreating are bitumen upgrading technologies designed to enhance fuel quality by decreasing its density, viscosity, boiling point and heteroatom content via hydrogen addition. The aim of this thesis is to model and simulate an upgrading and integrated gasification combined cycle then to evaluate the feasibility of integrating slurry hydrocracking, trickle-bed hydrotreating and residue gasification using the Aspen HYSYS® simulation software. The close-coupling of the bitumen upgrading facilities with gasification should lead to a hydrogen, steam and power self-sufficient upgrading facility with CO2 capture. Hydrocracker residue is first withdrawn from a 100,000 BPD Athabasca bitumen upgrading facility, characterized via ultimate analysis and then fed to a gasification unit where it produces hydrogen that is partially recycled to the hydrocracker and hydrotreaters and partially burned for power production in a high hydrogen combined cycle unit. The integrated design is simulated for a base case of 90% carbon capture utilizing a monoethanolamine (MEA) solvent, and compared to 65% and no carbon capture scenarios. The hydrogen production of the gasification process is evaluated in terms of hydrocracker residue and auxiliary petroleum coke feeds. The power production is determined for various carbon capture cases and for an optimal hydrocracking operation. Hence, the feasibility of the integration of the upgrading process and the IGCC resides in meeting the hydrogen demand of the upgrading facility while producing enough steam and electricity for a power and energy self-sufficient operation, regardless of the extent of carbon capture.
78

Shear-enhanced permeability and poroelastic deformation in unconsolidated sands

Hamza, Syed Muhammad Farrukh 06 November 2012 (has links)
Heavy oil production depends on the understanding of mechanical and flow properties of unconsolidated or weakly consolidated sands under different loading paths and boundary conditions. Reconstituted bitumen-free Athabasca oil-sands samples were used to investigate the geomechanics of a steam injection process such as the Steam Assisted Gravity Drainage (SAGD). Four stress paths have been studied in this work: triaxial compression, radial extension, pore pressure increase and isotropic compression. Absolute permeability, end-point relative permeability to oil & water (kro and krw), initial water saturation and residual oil saturation were measured while the samples deformed. Triaxial compression is a stress path of increasing mean stress while radial extension and pore pressure increase lead to decreasing mean stress. Pore pressure increase experiments were carried out for three initial states: equal axial and confining stresses, axial stress greater than confining stress and confining stress greater than axial stress. Pore pressure was increased under four boundary conditions: 1) constant axial and confining stress; 2) constant axial stress and zero radial strain; 3) zero axial strain and constant confining stress; and 4) zero axial and radial strain. These experiments were designed to mimic geologic conditions where vertical stress was either S1 or S3, the lateral boundary conditions were either zero strain or constant stress, and the vertical boundary conditions were either zero strain or constant stress. Triaxial compression caused a decrease in permeability as the sample compacted, followed by appreciable permeability enhancement during sample dilation. Radial extension led to sample dilation, shear failure and permeability increase from the beginning. The krw and kro increased by 40% and 15% post-compaction respectively for the samples corresponding to lower depths during triaxial compression. For these samples, residual oil saturation decreased by as much as 40%. For radial extension, the permeability enhancement decreased with depth and ranged from 20% to 50% while the residual oil saturation decreased by up to 55%. For both stress paths, more shear-enhanced permeability was observed for samples tested at lower pressures, implying that permeability enhancement is higher for shallower sands. The pore pressure increase experiments showed an increase of only 0-10% in absolute permeability except when the effective stress became close to zero. This could possibly have occurred due to steady state flow not being reached during absolute permeability measurement. The krw curves generally increased as the pore pressure was increased from 0 psi. The increase ranged from 5% to 44% for the different boundary conditions and differential stresses. The kro curves also showed an increasing trend for most of the cases. The residual oil saturation decreased by 40-60% for samples corresponding to shallow depths while it increased by 0-10% for samples corresponding to greater depths. The reservoirs with high differential stress are more conducive to favorable changes in permeability and residual oil saturation. These results suggested that a decreasing mean stress path is more beneficial for production increase than an increasing mean stress path. The unconsolidated sands are over-consolidated because of previous ice loading which makes the sand matrix stiffer. In this work, it was found that over-consolidation, as expected, decreased the porosity and permeability (40-50%) and increased the Young’s and bulk moduli of the sand. The result is sand which failed at higher than expected stress during triaxial compression. Overall, results show that lab experiments support increased permeability due to steam injection operations in heavy oil, and more importantly, the observed reduction in residual oil saturation implies SAGD induced deformation should improve recovery factors. / text
79

Integration and Simulation of a Bitumen Upgrading Facility and an IGCC Process with Carbon Capture

El Gemayel, Gemayel January 2012 (has links)
Hydrocracking and hydrotreating are bitumen upgrading technologies designed to enhance fuel quality by decreasing its density, viscosity, boiling point and heteroatom content via hydrogen addition. The aim of this thesis is to model and simulate an upgrading and integrated gasification combined cycle then to evaluate the feasibility of integrating slurry hydrocracking, trickle-bed hydrotreating and residue gasification using the Aspen HYSYS® simulation software. The close-coupling of the bitumen upgrading facilities with gasification should lead to a hydrogen, steam and power self-sufficient upgrading facility with CO2 capture. Hydrocracker residue is first withdrawn from a 100,000 BPD Athabasca bitumen upgrading facility, characterized via ultimate analysis and then fed to a gasification unit where it produces hydrogen that is partially recycled to the hydrocracker and hydrotreaters and partially burned for power production in a high hydrogen combined cycle unit. The integrated design is simulated for a base case of 90% carbon capture utilizing a monoethanolamine (MEA) solvent, and compared to 65% and no carbon capture scenarios. The hydrogen production of the gasification process is evaluated in terms of hydrocracker residue and auxiliary petroleum coke feeds. The power production is determined for various carbon capture cases and for an optimal hydrocracking operation. Hence, the feasibility of the integration of the upgrading process and the IGCC resides in meeting the hydrogen demand of the upgrading facility while producing enough steam and electricity for a power and energy self-sufficient operation, regardless of the extent of carbon capture.

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