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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.
21

The Investigation of Mysterious Marine Oil Spills on the West Coast of Canada

Szeto, Andrew 03 August 2012 (has links)
The Government of Canada’s National Aerial Surveillance Program (NASP) is responsible for the monitoring of ship based oil pollution in Canada’s three oceans. In many of these spills, the source of pollution is unknown as there are often no vessels found in the vicinity at the time of detection. In this work, the oil spills found in 2010 on the West Coast of Canada, alongside the collated vessel traffic data captured by the Canadian Coast Guard are investigated to determine the vessels most likely responsible for these spills. In terms of tools and techniques applied, oil spills are firstly hindcasted using the General NOAA Operational Modeling Environment (GNOME) to determine the location of their source. ArcGIS is used to geospatially reference and combine various data sets, and lastly the Analytical Hierarchy Process (AHP) is used to rank possible polluters found in the area of the spill.
22

Fingerprinting simulated marine oil spills with gasoline-range compound specific isotope correlation

Kory, Michael David 01 May 2012 (has links)
Environmental liability cases involving spilled or released petroleum products into ocean ecosystems require oil identification techniques that are unambiguous and conclusive, even in situations where oils have been subjected to secondary environmental processes, such as, evaporation and dissolution. The ability and functionality of the Compound Specific Isotope Correlation (CSIC) technique is tested to determine its reliability to characterize released petroleum using the carbon isotope ratios (13C/12C) of the individual gasoline-range compounds (C5-C9). In particular, this thesis studies the potential of CSIC as a robust diagnostic tool, to identify and correlate marine releases of oil with their sources, especially those having undergone evaporative weathering. Three crude oils (Alberta Sweet Mixed Blend, Lacula and Louisiana) added to synthetic seawater were exposed to mechanically simulated wave energy and controlled evaporative weathering at 10 oC. Time-series sampling of the gasoline-range vapour fractions from the headspace employed Solid Phase Micro Extraction (SPME). SPME-Continuous Flow-Isotope Ratio Mass Spectrometry (SPME-CF-IRMS) determined the molecular abundances and stable carbon isotope ratios (δ13C) of the gasoline-range compounds of the original and weathered oils. Evaporation rates over the maximum 20 hour period varied for the 3 study oils. Most (74%) of the individual compounds measured in the oils display a δ13C enrichment with progressive evaporation with approximately half of the compounds in all 3 oils showing fractionation of the carbon isotopes ≤ 0.5‰ within measurement precision. The magnitude of carbon isotope shift observed in compounds pre-vs. post-weathering ranges from 0 to 2.8 ±0.6‰. There is no clear relationship identified between the degree of 13C enrichment in the oils and groupings such as chemical class, structure or carbon number. The overall weighted average 13C enrichment for all compounds in the 3 oils is approximately 1‰. Toluene was the only compound consistently exhibiting comparatively high 13C enrichment (1.6‰, 1.8‰ and 2.8‰) in all 3 oils after evaporative weathering. Hierarchical Cluster Analysis (HCA) treatment of the CSIC data set can reliably discriminate between the 3 oils despite evaporative weathering and δ13C changes. HCA is also able to unambiguously relate the three weathered oils back to their respective original unweathered oil. Diagnostic shifts in δ13C of individual compounds in an oil may potentially be used to trace weathered oils back to the source, and possibly give a estimation of time since release. However the typically rapid rate of evaporation for the gasoline-range fractions limits the time that an oil can be successfully identified by CSIC. / Graduate
23

Eine Analyse des Kaufverhaltens bei Co-Brand-Produkten und der durch Co-Brand-Produkte inszenierten Rückwirkungseffekte auf die konstituierenden Marken /

Huber, Jan-Alexander. January 2004 (has links) (PDF)
Diss. Univ. Freiburg/Schweiz, 2004.
24

Akquisition neuer Zielgruppen : Integriertes Management von Akquisitions- und Spill-Over-Potentialen /

Koch, Markus. January 2006 (has links)
Thesis (doctoral)--Universität St. Gallen, 2006.
25

The multinational enterprise foreign market entry, transfer of technology and technology spillovers /

Müller, Thomas. Unknown Date (has links) (PDF)
University, Diss., 2003--München.
26

Targeted Delivery of Surfactants to the Oil-Water Interface Via Halloysite Nanotubes for Oil Spill Remediation

January 2020 (has links)
archives@tulane.edu / 1 / Azeem Farinmade
27

Evaluation of the Impact of the Deepwater Horizon Oil Spill and Hurricanes on Wildfires in Southeast Louisiana

Carley, Richard 11 May 2013 (has links)
Remotely sensed MODIS fire detections were used to examine wildfire variability from 2003-2011 in southeast Louisiana, and to determine if the Deepwater Horizon oil spill and hurricanes may have impacted fire frequency and intensity. Despite low wildfire detection rates, around 60% for fires at least 1 km2 or greater, the MODIS fire product provided a consistent and reliable source of wildfire data. As a result of Hurricane Katrina, wildfire detection frequencies doubled their average numbers during the fall of 2005 in inland areas and during the spring of 2006 in inland and coastal marsh areas. Strangely enough, the oil spill may have contributed to lower fire frequencies in the summer of 2010 and spring of 2011 inland. Neither hurricane Katrina nor the oil spill were found to have an effect on fire intensity, and the spatial distribution of wildfires remained relatively constant over the study area after both disasters.
28

Oil spill: are we doing enough to avoid it?

Pu, Jaan H. 19 April 2017 (has links)
Yes / This paper reviews the recent studies on the identification and cleaning methods, as well as the consequences of oil spill. The future progression on oil spill prevention studies are also projected here.
29

Water is More Important than Gold: Local Impacts and Perceptions of the 1995 Omai Cyanide Spill, Essequibo River, Guyana

Ramessar, Candice Rowena 21 August 2003 (has links)
Improved technologies, increases in global demand for metals, and lax environmental policies and regulations are causing a shift of large-scale mining activities to the tropics. This shift of mining to the tropics has the potential to modify natural ecosystems and disrupt the social structures of rural and indigenous peoples in some of the most remote areas of the planet. This thesis encompasses research done in two villages of Guyana's Essequibo River basin after the 1995 Omai cyanide spill, and illustrates the local social consequences of a large-scale gold mining operation in the tropics. It documents not only the degradation of the local river ecology, but also the changes in local people's perceptions of their environment. That environment, once viewed as pristine, is now viewed as unsafe, leading to disrupted livelihoods and lifestyles. The finding of this study points to a direct link between international economic liberalization policies (which emphasize privatization, foreign direct investment, and economic growth) and the creation of disaster circumstances in developing countries. This thesis research is the result of a total of ten weeks of participant observer research in the area of the Essequibo River, Guyana. It utilizes the methodology of taped interviews of head-of-households. Interviews were conducted with approximately 85 percent of heads-of household of the villages of Rockstone and Riversview. Additionally, interviews were conducted with national and regional governmental officials, regional health officials, local and indigenous leaders, personnel of the Guyana Geology and Mines Commission, and the Environmental Protection Agency in Guyana. Interviews were supplemented with archival research. The findings of this thesis research closely mirror those of other researchers who contend that the social impacts of technological disasters are long-term and more severe than those related to natural disasters. Seven years after the cyanide spill, disruptions in livelihood activities, diet, and household behaviors continued to be evident in the two villages. There is little indication that the high negative perceptions of the villagers as a result of the disaster will change in the near future. The research found that macroeconomic policies, crafted by national governments and overseen by international financial institutions without the involvement of local citizenry, disproportionately affected the poor and rural populations through the degradation of local ecosystems. The thesis also illustrates the usefulness of ethnographic research-in particular, interviews in disaster studies of developing countries. / Master of Science
30

The Role and Function of the Private Oil Spill Response Company:--Case Studies and Establishment of Framework for Taiwan--

Lin, Shih-Chang 03 September 2003 (has links)
none

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