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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.
211

Dynamics of perturbed exothermic bluff-body flow-fields.

Shanbhogue, Santosh Janardhan. January 2008 (has links)
Thesis (Ph.D.)--Aerospace Engineering, Georgia Institute of Technology, 2009. / Committee Chair: Lieuwen, Tim; Committee Member: Gaeta, Rick; Committee Member: Menon, Suresh; Committee Member: Seitzman, Jerry; Committee Member: Zinn, Ben.
212

Laser induced fluorescence imaging of counterflow diffusion flames

Tecu, Kirk S., January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Wanting leaf 133. Typescript. Vita. Includes bibliographical references (leaves 132-142). Also available on the Internet.
213

Soot emissions from turbulent diffusion flames burning simple alkane fuels /

Canteenwalla, Pervez M., January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2007. / Includes bibliographical references (p. 133-137). Also available in electronic format on the Internet.
214

Prediction of fire growth on furniture using CFD.

Pehrson, Richard. January 1999 (has links)
Thesis (Ph. D.)--Worcester Polytechnic Institute. / UMI no.: 99-37530. Includes bibliographical references (leaves 221-238).
215

Room/Corner fire calibration data marine composite screening specimens

Alston, Jarrod John. January 2004 (has links)
Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: heat fluxes; fire testing; composites; instrumentation; material properties. Includes bibliographical references.
216

One-dimensional computer modeling of electrical conductivity through methane and synthesis gas flames

Lilly, Jonathan Patrick. January 2006 (has links)
Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xvi, 291 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 289-291).
217

A computational fluid dynamics simulation model for flare analysis and control

Castiñeira Areas, David, January 1900 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.
218

Mammalian carnivores as bioindicators to evaluate the exposure and bioaccumulation of organic contaminants in terrestrial ecosystems

Boyles, Esmarie 01 May 2017 (has links)
To address my first objective, I opportunistically collected road-killed bobcats (n=44) throughout Illinois during 2013-2014, and analyzed their liver tissue for the presence of PCBs, PBDEs, and various other alternative halogenated flame retardants. Concentrations of ∑PCBs ranged from 76.4 ng/g lw to 3782 ng/g lw (median 562.97 ng/g lw). Male bobcats had significantly higher concentrations of PCBs than females (p = 0.04). Concentrations of ∑PBDEs (including all detectable PBDE congeners) ranged from 8.3 to 1920 ng/g lipid weight (median: 50.3 ng/g lw). Among the alternative flame retardants screened, Dechloranes (including anti- and syn-Dechlorane Plus and Dechlorane-602, 603, and 604), tetrabromo-o-chlorotoluene (TBCT), and hexabromocyclododecane (HBCD) were also detected frequently, with median concentrations of 28.7, 5.2, and 11.8 ng/g lw, respectively. Dechlorane analogue compositions in bobcats were different from that reported in other studies, suggesting species- or analogue-dependent bioaccumulation, biomagnification, or metabolism of Dechlorane chemicals in different food webs. My findings, along with previously reported food web models, suggest Dechloranes may possess substantial bioaccumulation and biomagnification potencies in terrestrial mammalian food webs. Thus, attention should be given to these highly bioavailable flame retardants in future environmental biomonitoring and risk assessments in a post-PBDE era. To address my second objective I collected raccoons (n=32) from various sites across Illinois and Missouri during 2013-2015. Liver tissues were analyzed for the presence of PBDEs and Dechloranes. ∑PBDE concentrations ranged from 19.1 ng/g lw to 2124 ng/g lw (median = 98.0 ng/g lw) and did not differ between gender or age of raccoon. Although nonsignificant (p=0.06), adult raccoons appeared to have greater PBDE concentration loads compared to juveniles. These nonsignificant differences are likely due to large variation in contaminant concentrations, possibly reflecting differences in individual raccoon diet and behavior. This is the first study reporting bioaccumulation of halogenated flame retardants in a wild felid in North America, and also the first report of PBDE accumulation in North American raccoons. The wide detection of Dechloranes, HBCD and TBCT in bobcats suggests a broad exposure of these alternative flame retardants in terrestrial apex predators in terrestrial ecosystems. The comparatively high levels of PBDEs in raccoons also suggest that biota in terrestrial habitats are still widely exposed to and susceptible to the bioaccumulation of these flame retardants.
219

Distribution of Polybrominated Diphenyl Ethers Among Demographic Categories

Merilis, Giorvanni 07 July 2017 (has links)
Polybrominated Diphenyl Ethers (PBDEs) are flame retardants widely used within the United States in various products such as plastics, electronics, textiles and furniture. With an increase in production and usage, PBDEs have recently emerged as a contaminant of concern. Due to their chemical structure, PBDEs have the propensity to bioaccumulate in mammals. In fact, elevated PBDE concentrations have been recorded in human breast milk. Due to the potential widespread exposure to PBDEs, this study investigates human blood concentrations of PBDEs generated through the 2003-2004 National Health and Nutrition Examination Survey. Through the use of statistical modeling, a comparison of mean PBDE concentrations in ng/g lipid is conducted based on age, gender and ethnicity. From a sample of 2337 individuals, the average blood concentration of PBDEs was approximately 81 ng/g lipid. The average PBDE concentration of males was significantly higher than females, using a 95% confidence level. In addition, PBDEs detected in human blood ranged approximately from 0.05 to 3676 ng/g lipid, with the highest concentrations found in black males. Also, a logistic regression analysis is conducted to determine whether an increase in background PBDE concentrations is a risk factor for obesity. Furthermore, the analyses of PBDEs are repeated for phthalates and polychlorinated Biphenyls for comparison. Finally, the measured concentrations of PBDEs are also compared to health outcome data known to show potential risk.
220

Soot Measurements in Steady and Pulsed Ethylene/Air Diffusion Flames Using Laser-Induced Incandescence

Sapmaz, Hayri Serhat 29 March 2006 (has links)
Combustion-generated carbon black nano particles, or soot, have both positive and negative effects depending on the application. From a positive point of view, it is used as a reinforcing agent in tires, black pigment in inks, and surface coatings. From a negative point of view, it affects performance and durability of many combustion systems, it is a major contributor of global warming, and it is linked to respiratory illness and cancer. Laser-Induced Incandescence (LII) was used in this study to measure soot volume fractions in four steady and twenty-eight pulsed ethylene diffusion flames burning at atmospheric pressure. A laminar coflow diffusion burner combined with a very-high-speed solenoid valve and control circuit provided unsteady flows by forcing the fuel flow with frequencies between 10 Hz and 200 Hz. Periodic flame oscillations were captured by two-dimensional phase-locked LII images and broadband luminosity images for eight phases (0°- 360°) covering each period. A comparison between the steady and pulsed flames and the effect of the pulsation frequency on soot volume fraction in the flame region and the post flame region are presented. The most significant effect of pulsing frequency was observed at 10 Hz. At this frequency, the flame with the lowest mean flow rate had 1.77 times enhancement in peak soot volume fraction and 1.2 times enhancement in total soot volume fraction; whereas the flame with the highest mean flow rate had no significant change in the peak soot volume fraction and 1.4 times reduction in the total soot volume fraction. A correlation (ƒv Reˉ1 = a+b· Str) for the total soot volume fraction in the flame region for the unsteady laminar ethylene flames was obtained for the pulsation frequency between 10 Hz and 200 Hz, and the Reynolds number between 37 and 55. The soot primary particle size in steady and unsteady flames was measured using the Time-Resolved Laser-Induced Incandescence (TIRE-LII) and the double-exponential fit method. At maximum frequency (200 Hz), the soot particles were smaller in size by 15% compared to the steady case in the flame with the highest mean flow rate.

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