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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.
1

Impact of flare destruction efficiencies on ozone concentrations: a case study for Houston, Texas

Alfadhli, Fahad Mohammed 25 October 2010 (has links)
Industrial flaring can result in atmospheric emissions that have significant impact on regional air quality. This study investigates the impact on one-hour average ozone concentrations due to industrial flaring, using the region around Houston, Texas as a case study. Specifically, this study examined the impact on ozone formation of different flare destruction efficiencies. There are some concerns about whether flare destruction efficiency is reduced from design conditions (98 to 99% destruction) at low flare flow rates. Some studies have reported very low flares destruction efficiencies under low flow, so it is possible that ozone precursor emissions may be underestimated by an order of magnitude or more at low flow conditions. In this thesis, 100 different destruction efficiency scenarios have been constructed where destruction efficiency depends on the ratio of flare flow rate to the maximum flow rate (turndown ratio). The scenarios differ in the assumed destruction efficiency at near zero flow and the turndown ratio at which destruction efficiency returns to the design value. These destruction scenarios are applied to hourly mass flow data for twenty-five flares in Houston, Texas. The scenarios have very different impacts on air quality. The air quality implications of these results for possible modifications to flare operation are explored. / text
2

Investigations into high latitude stratospheric chemistry

Lutman, Emma Rachel January 1995 (has links)
No description available.
3

Numerical model studies of the chemistry of the northern hemisphere lower stratosphere

Kettleborough, James Anthony January 1995 (has links)
No description available.
4

Moral cathedrals : war damage and Franco-German cultural propaganda on the Western Front 1870-1938

Lambourne, Nicola January 1997 (has links)
No description available.
5

The effects of forest fragmentation on leaf-litter invertebrates in Central Amazonia

Didham, Raphael K. January 1996 (has links)
No description available.
6

Bluffing with a pair of deuces the downside of successful deception

Sharpe, Richard R. 06 1900 (has links)
This thesis examines two examples of strategic deception campaigns - interwar Germany and modern Iraq - to determine the necessity for a clear framework, to decide how deception campaigns might meet overall national strategic goals. With the mindset of a pending overhaul in the way that the Department of Defense conducts business, understanding the importance of deception will become increasingly vital as the military becomes lighter and leaner. With such a change in the makeup of the force, old conventions of warfare, requiring a numerical advantage, may have to be forsaken in favor of techniques traditionally considered unconventional. By developing such a doctrine now, the challenge can be met before it actually arises. The key to doing so is examining past successes and failures and learning from history's mistakes. Using the DoD framework as a basis, it is possible to use the analysis of these case studies to develop a planning method to mitigate many of the hurdles experienced in these campaigns, from planning and execution to termination. / US Air Force (USAF) author.
7

Operationalizing dissuasion

Rushton, James A. 06 1900 (has links)
Dissuasion is a strategy for persuading adversaries to seek acceptable alternatives to building threatening capabilities or adopting hostile intentions towards the United States. Dissuasion is a framework for organizing strategy directed at dealing with future threats. As such, it compliments other traditional national strategies (such as deterrence or coercion), and uses deterrence, coercion, and even appeasement, to meet overall policy goals. Dissuasion as a strategy was not formally articulated until it appeared in the 2001 Quadrennial Defense Review. Despite dissuasionâ s comparatively recent recognition, its historical use by states attempting to influence geopolitical rivals has been frequent. Dissuasion is stated as a primary strategy in the capstone national security documents of the United States, but clear guidelines on how dissuasion can be implemented are lacking. This study expands the understanding of dissuasion as a strategy, examining three historical instances where it was used by states seeking to influence the behavior or military force structure building of other states, bringing dissuasion out of the realm of theory and into the real-world. Tools and procedures are described in order to â operationalizeâ dissuasion, the role of naval forces in dissuasion is scrutinized, and the vital intersection of strategic culture and dissuasion is examined. / US Navy (USN) author.
8

NATO's Weapons of Mass Destruction Initiative : achievements and challenges

Bravo, Iliana P. 09 1900 (has links)
Approved for public release; distribution is unlimited / This thesis analyzes the Weapons of Mass Destruction Initiative (WMDI) taken by the North Atlantic Treaty Organization (NATO) in April 1999. The analysis considers the achievements of the WMDI as well as the obstacles and challenges the Alliance faces in countering WMD threats. For over a decade, the Alliance has been concerned about the threats posed by biological, chemical, nuclear, and radiological weapons. In 1994, NATO established the Senior Political-Military Group on Proliferation and the Senior Defense Group on Proliferation to implement alliance policy on WMD proliferation. Through the WMDI, NATO enhanced its efforts to address these threats through the establishment of a WMD Center at NATO Headquarters in Brussels to facilitate dialogue and coordination relating to threat assessment, and to develop responses to such threats. At the Prague Summit in November 2002 the Allies made firmer commitments to develop capabilities to respond to WMD threats. The new measures include the Prague Capabilities Commitment and the NATO Response Force. / Civilian, Department of the Navy
9

Functionalization and modification of nanoparticles and their biomedical application / Fonctionnalisation et transformation de nanoparticules et leur application biomédicale

Turcheniuk, Volodymyr 03 October 2016 (has links)
L’objectif primordial a été le développement de stratégies de fonctionnalisation de surface polyvalente pour différentes nanoparticules notamment de nanoparticules de diamant, les nanostructures en or et ses nanocomposites. Un objectif particulier a été l'utilisation du graphène oxide réduite et des nanostructures en or pour l'ablation photo-thermique ou photo-dynamique des pathogènes.Incorporation de la vertéporfine, un photo-sensibiliteur cliniquement approuvé, sur des nanostructures en a permis une éradication efficace d'une souche virulente de E. coli associé à une infection des voies urinaires. L’utilisation du graphène oxide reduite,lorsqu'il est éclairé avec un laser infrarouge proche, a permis une destruction photothermique de la même souche de E. coli.En parallèle, l'intérêt d'utiliser des nanoparticules de diamant (NDs) modifié avec le menthol ainsi que différents sucres comme agent antibactérien contre les bactéries Gram-positif (Staphylococcus aureus) et Gram négatif (Escherichia coli) a été montré. Une stratégie pour l’intégration covalente des sucres, en tirant profit de la photochimie de arylazides, a été développée en parallèle. Le nitrène, une intermédiaire très réactif, est censé interagir avec des glycanes en créant des liaisons covalentes très robustes. Les glyco- NDs ainsi formés ont maintenu leur affinité envers des lectines. Grâce à un test d'agglutination à la base de fluorescence nous avons montré que les particules mannan-NDs montrent un effet d’agglutination des E. coli à des concentrations de ≈10 pg ml - 1, étant beaucoup plus faible que le mannan libre et mannose-NDs. / The primal focus of the research work was the development of versatile surface functionalization strategies for different nanoparticles ranging from diamond nanostructures to gold nanorods and nanocomposites. One particular aim was the use of reduced grpahene oxide (rGO) and silica coated gold nanorods for the photothermal and photodynamic ablation of pathogens. Embedding of verteporfin, a clinically approved photosensitizer, into silica-coated gold nanorods allowed an efficient eradicaiton of a virulent strain of E. coli associated with urinary tract infection. The great heating effect of graphene-coated gold nanorods when illuminated with a near-infrared laser allowed for a photothermal destruction of the same pathogenic strain. In parallel, we have shown the interest of using diamond nanoparticles (NDs) modified with menthol as well as different sugars as antibacterial agent against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia Coli) bacteria. We developed a strategy for the covalent attachment of sugars by taking advantage of the photochemistry of arylazides, which upon light activation convert to reactive nitrenes. The highly reactive nitrene intermediate formed is believed to interact with glycans through C-H and N-H insertion reactions, creating highly robust covalent linkages. The resulting glyco-NDs maintained their expected binging affinity and specificity towards their partner lectins. Through a fluorescent based agglutination assay, we showed that mannan-NDs display E. coli agglutination at concentrations of ≈10 µg mL-1, being much lower than free mannan and mannose-NDs.
10

The Evolution of the Built Environment of Heritage Communities: Comparative Case Study of St. Jacobs and Creemore, Ontario

Randle, Kathryn 26 March 2012 (has links)
Many rural communities utilize heritage resources as a tourism strategy to attract urban residents who desire the amenities found in historic communities. Current research finds that increased investment and popularity may cause these places to evolve through three phases (town-scape, heritage-scape and leisure-scape); a process referred to as creative destruction (Mitchell 1998). The purpose of this study is to determine if changes to the built form accompany this evolutionary sequence. A comparative analysis of two small Ontario communities at different stages of development (St. Jacobs and Creemore) is undertaken. Three objectives guide the research. The first objective is to assess the changes that have occurred to built form in a heritage-scape (Creemore) and leisure-scape (St. Jacobs) setting. To meet the first objective, three research methods, townscape assessment, individual building evaluation, and business survey are used. This study found that today, significantly more buildings have heritage value in Creemore, a heritage-scape, than in St. Jacobs, a leisure-scape. More new development that is not sensitive to the heritage character of the area has taken place in St. Jacobs than in Creemore. Therefore, heritage buildings are compromised as villages move through the stages of creative destruction and experience the conditions associated with the landscapes of heritage-scape and leisure-scape. During the landscape of heritage-scape, community members are aware of the heritage character and the importance of the historical built environment. Here, most business owners take initiatives to maintain and even enhance the built environment. The second objective is to understand the factors responsible for the identified heritage structure in each village. The role of the private sector, public and civic sectors is assessed to meet this objective. The study found that community involvement is integral to retaining the heritage character of the area and had tremendous impact on the conservation of heritage resources and the enhancement of the small town Ontario character. As important are the County and Township policies which define how and where the community will grow. Both the County and Township policies guiding land use in Creemore are more detailed and focused on heritage protection than are those pertaining to St. Jacobs. Both of these factors were stronger in Creemore, a heritage-scape than St. Jacobs, a leisure-scape. The final objective is to provide recommendations for future development on the assumption that both towns will continue to face growth pressures. The research offers five recommendations: strengthen policy and enhance its implementation, devise design guidelines and ensure documentation of resources, educate community members on heritage resources and ways to protect them, strengthen community ties to foster greater appreciation for heritage resources and the streetscape, and devise a balanced tourism strategy to maintain the resources that ultimately draw tourists to the villages.

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