Graduate Theses & Dissertations

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Mitigating Cold Flow Problems of Biodiesel
The present thesis explores the cold flow properties of biodiesel and the effect of vegetable oil derived compounds on the crystallization path as well as the mechanisms at play at different stages and length scales. Model systems including triacylglycerol (TAG) oils and their derivatives, and a polymer were tested with biodiesel. The goal was to acquire the fundamental knowledge that would help design cold flow improver (CFI) additives that would address effectively and simultaneously the flow problems of biodiesel, particularly the cloud point (CP) and pour point (PP). The compounds were revealed to be fundamentally vegetable oil crystallization modifiers (VOCM) and the polymer was confirmed to be a pour point depressant (PPD). The results obtained with the VOCMs indicate that two cis-unsaturated moieties combined with a trans-/saturated fatty acid is a critical structural architecture for depressing the crystallization onset by a mechanism wherein while the straight chain promotes a first packing with the linear saturated FAMEs, the kinked moieties prevent further crystallization. The study of model binary systems made of a VOCM and a saturated FAME with DSC, XRD and PLM provided a complete phase diagram including the thermal transformation lines, crystal structure and microstructure that impact the phase composition along the different crystallization stages, and elicited the competing effects of molecular mass, chain length mismatch and isomerism. The liquid-solid boundary is discussed in light of a simple thermodynamic model based on the Hildebrand equation and pair interactions. In order to test for synergies, the PP and CP of a biodiesel (Soy1500) supplemented with several VOCM and PLMA binary cocktails were measured using a specially designed method inspired by ASTM standards. The results were impressive, the combination of additives depressed CP and PP better than any single additive. The PLM and DSC results suggest that the cocktail additives are most effective when the right molecular structure and optimal concentration are provided. The cocktail mixture achieves then tiny crystals that are prevented from aggregating for an extended temperature range. The results of the study can be directly used for the design of functional and economical CFI from vegetable oils and their derivatives. Author Keywords: Biodiesel, Microstructure, Polymorphism, Pour point depressants, Triacylglycerol, Vegetable Oil Based Crystal Modifier
Rights, Resources, and Resistance
The development of pan-Indigenous political organizations in northeastern Alberta in the context of oil and gas development during the 1970s created disparate effects on Indigenous communities in the region. Resistance to assimilation policies led the Indian Association of Alberta to transform itself into a unified voice that represented Aboriginal and treaty rights in the late 1960s; however, the organization lost legitimacy following the divergence of goals between influential Indigenous leaders, Harold Cardinal and Joseph Dion. Tripartite agreements began to unfold between the federal and provincial governments, the oil and gas industry, and individual local leadership; environmental degradation spread throughout the landscape. Some communities benefitted financially whereas other communities, like Lubicon Lake Nation, received little compensation and felt the full force of industrial contamination of their traditional territories. Without the support of pan-Indigenous political organizations, Lubicon Lake developed an individual response that was successful in gaining international attention to their conditions. Author Keywords: 1970s, Indigenous politics, Lubicon Lake Nation, northern Alberta, political economy, tar sands
Exploring and Evaluating Personal, Cultural and Social Food Needs and the Role of a Community Freezer among Inuit in Hopedale, Nunatsiavut
This thesis sought to explore and evaluate perceptions of food needs and the role of a community freezer in addressing those needs, among Inuit in Hopedale, Nunatsiavut (Northern Labrador). Research was carried out through an exploratory sequential mixed-methods design. Phase 1 employed qualitative interviews with community members in Hopedale to explore the perceptions of food needs from an Inuit perspective. Results from Phase 1 identified a series personal, physical, cultural, and social food needs that informed the development of a series of questions that were integrated into a community-wide survey that was implemented in Phase 2. Results from Phase 2 identified a series of cultural, household and individual characteristics that significantly impact perceived ability to meet needs among community members in Hopedale. Findings from this research contribute to our understanding of food needs, and may potentially influence estimates of levels of needs that are protected in Inuit land claims, and inform the development or improvement of community methods for food support. Author Keywords: Food Needs, Food Programs, Food Security, Indigenous, Inuit, Mixed-Methods
Tłı̨chǫ, Co-management and the Bathurst Caribou Herd, 2009-2011
Since time immemorial caribou have been and remain central to Tłı̨chǫ life and culture. As early as the late 19th century, Canada began to implement wildlife management policies in the NWT in response to concern over the health and future of caribou populations. However, the 2005 Tłı̨chǫ Land Claims and Self-Government Agreement (Tłı̨chǫ Agreement) signed by the Tłı̨chǫ, the Government of the Northwest Territories and the Canadian Government outlines that Tłı̨chǫ will have a say in wildlife management on Tłı̨chǫ Lands. Co-management is the power-sharing model used in an effort to ensure that the Tłı̨chǫ voice is heard in these decisions. My thesis centres on the 2009-2011 co-management process and the resulting final management decisions regarding monitoring and management actions to promote the stabilization and recovery of the Bathurst Caribou herd. I focus my analysis on the Tłı̨chǫ perspective as expressed during this co-management process. I conclude that while Tłı̨chǫ perspectives were presented in the hearings and related processes, they were not well represented in the final management actions. This omission speaks to the wider issue of how aboriginal people are treated and understood in Canada. Author Keywords: Canada, Caribou, Co-management, Northwest Territories, Tłı̨chǫ
Witches and Bawds as Elderly Women in England, 1680-1730
Many print sources from 1680 to 1730 depicted bawds and witches as figures of transgressive elderly femininity. They were often described as having roughly the same anti-social behaviour, age, and gender. Both witches and bawds were seen as seducing innocents into a life of sin, associating with the devil, and acting lustful and unmotherly. Furthermore, they were connected with Catholicism and were thought to unite sinners against English Protestant society. The physical descriptions of the witch and procuress also bore significant patterns in presenting deformity, disfigurement, smelliness, rottenness, and death, traits generally connected with elderly women. Though historians have recognized the tendency of the witch or bawd to be characterized as an old woman, none have conducted a systematic comparison of the two stereotypes. Such an analysis can offer insight about the social anxieties around aging femininity in this period. Author Keywords: bawd, cheap print, elderly women, old age, witch, witchcraft
Alone in Power
The thesis uses three case studies of President Nixon’s foreign policy in South-east Asia to analyze presidential domestic-making. The theoretical concept of personality politics is used to analyze the Nixon administration and foreign policy. Nixon’s secretive nature combined with his mistrust of the press and bureaucracy to create an office structure that restricted the involvement and notification of others of his foreign policy. This thesis also takes into account the domestic climate that Nixon was operating within, including significant antiwar opposition, an adversarial media, and an ideologically opposed bureaucracy. Nixon’s foreign policy was ultimately the result of a perfect storm of factors. The president’s natural penchant for secrecy, along with his mistrust of the press and bureaucracy, combined with the American political environment that was in many instances ideologically set against him, also helped shape his foreign policy. Author Keywords: American Presidency, China, National Security Council, Richard Nixon, US Foreign Policy, 1969-1973, Vietnam War
Investigating Ecological Niche Differentiation Among Wild Candids Experiencing Hybridization in Eastern North America
Currently there are large areas of the North American landscape that are occupied by Canis spp. hybrids of several varieties, leading to the logical question as to the genetic structure and ecological function of Canis populations across the continent, and to what extent hybrids reflect contemporary landscapes. This study illustrated patterns of niche differentiation between parental canid species and their hybrids using individual high quality genetic profile and species distribution models to support the intermediate phenotype hypothesis. In general, hybrids demonstrated an intermediate habitat suitability compared to its parental species, across most environmental variables used. A similar trend was observed in the niche metric analysis, where we found that hybrids exhibit intermediate niche breadth, with eastern coyotes and eastern wolves exhibiting the broader and narrower niche, respectively. Our results demonstrate that the intermediate phenotype hypothesis is supported even at a large scale and when involving highly mobile large mammal species. Author Keywords: canid, ecological niche modelling, hybridization, intermediate phenotype, microsatellite genotype, niche differentiation
Situating Copper Bells in Prehispanic Southwest Societies
This thesis examines the spatial, temporal, and contextual distribution of copper bells in the Greater Southwest region and how they are situated in archaeological literature. To date, 672 copper bells have been found in at least 113 different Southwestern sites dating from ca. A.D. 900-1450, though there is no archaeological evidence for metallurgical activities in the area at this time. The origin of copper bells has been assumed to be West Mexico, a region known for its metallurgical traditions and whose inhabitants produced copious amounts of similar bells. Various lists of copper bells discovered have been compiled over the years, but little consideration has been given to the role these artifacts may have played in Southwestern societies. Copper bells are frequently labelled as prestige goods in archaeological literature, a term which fails to account for their significant depositional variation. By updating the database of known Southwestern copper bells, it becomes possible to examine these contextual distributions in greater detail. It is concluded that the prestige goods model is not suitable for Southwestern copper bells in many cases, and that alternative frameworks such as inalienable possessions are a better fit for these artifacts. Author Keywords: Archaeology, copper bells, inalienable possesions, interaction, U.S. Southwest
Cemeteries and Hunter-Gatherer Land-Use Patterns
The principle aim of this thesis is to evaluate the applicability of the Goldstein/Kelly hypothesis, which proposes that hunter-gatherer cemeteries emerge as a product of resource competition, and function to confirm and maintain ancestral ties to critical resources. My evaluation centres on a case study of the earliest known cemeteries of the middle Trent Valley, Ontario. To determine whether these predictions are true, I investigated the ecological context of local wetland-based foraging, and undertook a locational analysis to determine if the placement of cemeteries correlates with environmental characteristics that reflect the presence of valuable resources that are unique to these locations. The analysis reveals that ancient cemeteries in the middle Trent Valley were located near seasonal riparian wetlands, possibly to secure wild rice and the variety of fauna it attracts. Through the integration of paleoecological, archaeological, and ethnographic information for the region, this research finds support for the Goldstein/Kelly hypothesis. Author Keywords: Cemeteries, Hunter-Gatherers, Landscape Archaeology, Late Archaic, Middle Woodland, Ontario

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Format: 2024/05/06