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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.
31

Investigation of spontaneous combustion phenomenology of bagasse and calcium hypochlorite / Spontaneous combustion of bagasse and calcium hypochlorite

Halliburton, Brendan William January 2002 (has links)
Thesis (PhD)--Macquarie University, Division of Environmental and Life Sciences, Department of Chemistry, 2002. / Bibliography: leaves 234-240. / Introduction, theoretical descriptions of spontaneous combustion phenomena and aims of this thesis -- Laboratory measurements of the self-heating phenomenology of bagasse -- Field experiments investigating the self-heating behaviour of large scale stockpiles of low symmetry -- Self-heating and thermal ignition of calcium hypochlorite -- Experimental methods and procedures used for the critical ambient temperature of HCH -- Results of critical ambient temperature measurements upon single containers of hydrated high strength HCH -- Experiments on the interaction of self-heating drums -- Conclusions. / The hazard of spontaneous combustion is a problem that confronts any industry that transports or stores a reactive material. Bagasse is a reactive material that presents an expensive spontaneous combustion hazard for the sugar industry since this material is the principal fuel used at sugar mills. Calcium Hypochlorite is another such material presenting a significant industrial spontaneous combustion hazard for the transport and insurance industry as it has been linked to a number of expensive maritime conflagrations. The investigation of fundamental self-heating phenomenon is critical for the understanding, control and prevention of spontaneous ignition with these materials. -- By way of isothermal calorimetry techniques and fundamental thermal ignition measurements, this study has provided improved understanding into the oxidative self-heating phenomenology of bagasse and thermal ignition phenomenology of calcium hypochlorite. Both substances have been shown to possess unusual and previously unknown self-heating behaviour at temperatures below 100°C, with water being a principal component of each mechanism. -- The outcomes of this study have provided a platform which has enabled current mathematical models to predict large scale self-heating phenomena for industrially stored quantities of these materials. / Mode of access: World Wide Web. / 240 leaves, bound ill
32

Spontaneous abortion risk in women textile workers in Shanghai, China /

Wong, Eva Y. January 2007 (has links)
Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 88-98).
33

Study of heat production and transfer in shredded tires /

Sellassie, Kassahun G., January 2004 (has links)
Thesis (Ph. D.)--Lehigh University, 2005. / Includes vita. Includes bibliographical references (leaves 232-245).
34

The application of numerical modelling to the assessment of the potential for, and the detection of, spontaneous combustion in underground coal mines /

Humphreys, D. R. January 2004 (has links) (PDF)
Thesis (Ph.D.) - University of Queensland, 2004. / Includes bibliography.
35

Understanding pneumothorax : epidemiology, physiology and predicting outcome

Hallifax, Robert January 2018 (has links)
Contrary to traditional teaching, patients with Primary Spontaneous Pneumothorax (PSP) do not have normal lungs. Emphysema-like change (ELC) and inflammation are common. However, the natural history of ELC and its significance in terms of future disease is not known. Current management of pneumothorax is generic and not personalised. This thesis updates the UK epidemiology of pneumothorax, describes the use of two novel methods to examine the lungs, a method of predicting early treatment failure, the association of CT findings and recurrence, and a systematic review of chemical pleurodesis to reduce recurrence. Analysis of fifty years' data on ~150,000 admissions demonstrated that the incidence of pneumothorax is increasing, and established a method to identify primary from secondary pneumothoraces and their relative risk of recurrence. Reduced ventilation of hyperpolarised Xenon on enhanced-Magnetic Resonance Imaging (MRI) was seen in those PSP patients with greater low attenuation areas on Computed Tomography (CT) and with reduced pulmonary function. A model of lung inhomogeneity found that metrics of lung ventilation distinguished pneumothorax patients from healthy volunteers and Chronic Obstructive Pulmonary Disease (COPD) patients. This may represent subtle or mild disease, not identified on standard testing, which may be exacerbated by smoking. CT scanning found that mild emphysema and cystic airspaces were common in PSP patients. Ex- or current smokers had more (and larger) cysts. Emphysema was more common in smokers and patients with a history of previous pneumothorax: who were at higher risk of recurrence. However, variation in number and size of cysts were seen in both those patients with and without recurrence. As such, no single algorithm to predict recurrence was identified. Airflow measurement early in the patient pathway has the potential to identify those likely to fail treatment, potentially allowing early triage to surgery. The addition of talc or minocycline as an adjunct to surgery provides the lowest recurrence rates, but physician-led talc poudrage may be similarly effective. Those in whom surgery is not suitable, chemical pleurodesis could be offered via chest drain. Data presented in this thesis thus provides insights into the underlying abnormalities in PSP and lays the groundwork for strategies to fundamentally alter the management paradigm.
36

Alternative Memorials: Death and Memory in Contemporary America / Death and Memory in Contemporary America

Dobler, Robert, 1980- 09 1900 (has links)
x, 89 p. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Alternative forms of memorialization offer a sense of empowerment to the mourner, bringing the act of grieving into the personal sphere and away from the clinical or official realm of funeral homes and cemeteries. Constructing a spontaneous shrine allows a mourner to create a meaningful narrative of the deceased's life, giving structure and significance to a loss that may seem chaotic or meaningless in the immediate aftermath. These vernacular memorials also function as focal points for continued communication with the departed and interaction with a community of mourners that blurs distinctions between public and private spheres. I focus my analysis on MySpace pages that are transformed into spontaneous memorials in the wake of a user's death, the creation of "ghost bikes" at the sites of fatal bicycle-automobile collisions, and memorial tattooing, exploring the ways in which these practices are socially constructed innovations on the traditional material forms of mourning culture. / Committee in Charge: Dr. Daniel Wojcik, Folklore, Chair; Dr. Philip Scher, Anthropology; Dr. Doug Blandy, Arts and Administration / 2016-05-28
37

Comparação entre a ventilação com pressão positiva intermitente ou pressão controlada em equinos anestesiados com isofluorano

Bechara, Juliana Noda [UNESP] 14 February 2003 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-02-14Bitstream added on 2014-06-13T21:02:17Z : No. of bitstreams: 1 bechara_jn_dr_jabo.pdf: 522049 bytes, checksum: 69aeded0d4620c6c2721ab82f9614fd2 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os principais fatores a serem considerados durante a anestesia em eqüinos são a depressão cardiovascular e ventilatória e suas implicações hemodinâmicas. O objetivo do presente estudo foi o de avaliar duas modalidades ventilatórias na espécie eqüina e as repercussões destes modos de ventilação nos parâmetros ventilatórios, hemodinâmicos e mecânica respiratória. Foram utilizados 19 eqüinos clinicamente sadios, em decúbito lateral, aleatoriamente divididos em dois grupos, sendo que no Grupo I foi realizada a ventilação com pressão positiva intermitente e, no Grupo II com pressão controlada. O experimento foi dividido em duas fases, sendo que na primeira foram avaliados os parâmetros ventilatórios e de mecânica respiratória e, na segunda fase, além desses, também foram avaliados os parâmetros hemodinâmicos. Observou-se melhora dos parâmetros de ventilação em relação aos momentos de ventilação espontânea, quando empregou-se a ventilação controlada. Não foram observadas alterações hemodinâmicas e de oxigenação quando comparados os diferentes momentos num mesmo grupo, porém os valores da pressão venosa central e da pressão da artéria pulmonar foram superiores no grupo da ventilação com pressão positiva intermitente. Concluiu-se que não há diferença entre a ventilação com pressão positiva intermitente e a ventilação com pressão controlada em eqüinos clinicamente saudáveis. / The most important factors to be considered in equine anesthesia are the cardiovascular and ventilatory depressions and further hemodynamic failure. The purpose of the present study was to evaluate two modes of mechanical ventilation in horses and their repercussion on ventilatory and hemodynamic parameters and respiratory mechanics also. Nineteen healthy horses in lateral recumbency, were randomly assigned into two groups. In Group I, intermittent positive pressure ventilation was used and, in Group II, pressure controlled ventilation. The experiment was divided into two phases, in the first ventilatory parameters and respiratory mechanics were evaluated and in the second phase, hemodynamic parameters were also measured. A significant improvement was observed in ventilatory parameters when compared controlled to spontaneous ventilation. No changes in hemodynamic and oxygenation parameters were observed, but central venous pressure and pulmonary arterial pressure were higher with intermittent positive pressure ventilation. In conclusion, there is no difference between intermittent positive pressure ventilation and pressure controlled ventilation in healthy horses.
38

Norm evolution without the state : an examination of the unique nature of commercial law

Druzin, Bryan Howard 11 1900 (has links)
The discussion examines the idea that because of its relatively unique nature, commercial law has the distinct ability to evolve and function in the absence of a central coercive authority. While law of a non-commercial nature generally requires the backing of a state through which to derive its efficacy, a great deal of commercial law as it exists today evolves often in the absence of a single coercive authority, shaped largely by market forces outside the purview of any one state power. To this end, we look primarily at transnational commercial law, specifically at what is commonly understood as the new law merchant. It is the central contention of this paper that commercial law stands apart from other forms of law in that it is uniquely equipped to generate norms in situations where a single legislative power is notably not present, as it is largely impacted by the choices and behaviour of individual economic actors. We examine the notion that the manner of interaction implied by commercial intercourse involves a higher degree of overall engagement. This we term ‘high engagement’, which we divide into two elements: repetition and game creation, which with reciprocity, works in tandem to produce identifiable legal norms and the subsequent compliance with them. In Part I, after presenting a brief overview of the idea of reciprocity and spontaneous law theory, a more detailed explanation of the notion of engagement is offered. In Part II, we set out exactly how high engagement facilitates the development of and compliance with legal norms. Finally, the conclusion this paper reaches is that this element of high engagement, a salient characteristic of commercial interaction, plays a decisive role in the ability of commercial law to evolve and function in the vacuum of a central legislative authority. / Law, Faculty of / Graduate
39

The Recombination Mechanism and True Green Amplified Spontaneous Emission in CH3NH3PbBr3 Perovskite

Priante, Davide 08 1900 (has links)
True-green wavelength emitters at 555 nm are currently dominated by III-V semiconductor-based inorganic materials. Nevertheless, due to high lattice- and thermal-mismatch, the overall power efficiency in this range tends to decline for high current density showing the so-called efficiency droop in the green region (“green gap”). In order to fill the research green gap, this thesis examines the low cost solution-processability of organometal halide perovskites, which presents a unique opportunity for light-emitting devices in the green-yellow region owing to their superior photophysic properties such as high photoluminescence quantum efficiency, small capture cross section of defect states as well as optical bandgap tunability across the visible light regime. Specifically, the mechanisms of radiative recombination in a CH3NH3PbBr3 hybrid perovskite material were investigated using low-temperature, power-dependent (77 K), temperature-dependent photoluminescence (PL) measurements. We noted three recombination peaks at 77K, one of which originated from bulk defect states, and other two from surface defect states. The latter were identified as bound-excitonic (BE) radiative transitions related to particle size inhomogeneity or grain size induced surface state in the sample. Both transitions led to PL spectra broadening as a result of concurrent blue- and red-shifts of these excitonic peaks. The blue-shift is most likely due to the Burstein-Moss (band filling) effect. Interestingly, the red-shift of the second excitonic peak becomes pronounced with increasing temperature leading to a true-green wavelength of 553 nm for CH3NH3PbBr3. On the other hand, red-shifted peak originates from the strong absorption in the second excitonic peak owed to the high density of surface states and carrier filling of these states due to the excitation from the first excitonic recombination. We also achieved amplified spontaneous emission around excitation threshold energy of 350 μJ/cm2 when optically pumped using 475 nm laser pulses, thus supporting the assignment of carrier absorption and re-excitation mentioned above. This dissertation work led to the following article: D. Priante, I. Dursun, M. S. Alias, D. Shi, V. A. Melnikov, T. K. Ng, O. F. Mohammed, O. M. Bakr, and B. S. Ooi, "The recombination mechanisms leading to amplified spontaneous emission at the true-green wavelength in CH3NH3PbBr3 perovskites", Applied Physics Letters, 106, 081902, 2015. DOI: 10.1063/1.4913463
40

Aggregative Growth of Colloidal Semiconducting Nanocrystals for Nanoshell Quantum Dots and Quantum Dot Molecules

Cassidy, James 13 May 2022 (has links)
No description available.

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