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- Title
- A 2009 MOBILE SOURCE EMISSIONS INVENTORY OF THE UNIVERSITY OF CENTRAL FLORIDA.
- Creator
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Clifford, Johanna, Cooper, David, University of Central Florida
- Abstract / Description
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This thesis reports on the results of a mobile source emissions inventory for the University of Central Florida (UCF). For a large urban university, the majority of volatile organic compounds (VOC), oxides of nitrogen (NOx), and carbon dioxide (CO2) emissions come from on-road sources: personal vehicles and campus shuttles carrying students, faculty, staff, and administrators to and from the university, as well as university business trips. In addition to emissions from daily commutes, non...
Show moreThis thesis reports on the results of a mobile source emissions inventory for the University of Central Florida (UCF). For a large urban university, the majority of volatile organic compounds (VOC), oxides of nitrogen (NOx), and carbon dioxide (CO2) emissions come from on-road sources: personal vehicles and campus shuttles carrying students, faculty, staff, and administrators to and from the university, as well as university business trips. In addition to emissions from daily commutes, non-road equipment such as lawnmowers, leaf blowers, small maintenance vehicles, and other such equipment utilized on campus contributes to a significant portion to the total emissions from the university. UCF has recently become the second largest university in the nation (with over 56,000 students enrolled in the fall 2010 semester), and contributes significantly to VOC, NOx, and CO2 emissions in Central Florida area. In this project, students, faculty, staff, and administrators were first surveyed to determine their commuting distances and frequencies. Information was also gathered on vehicle type, and age distribution of the personal vehicles of students, faculty, administration, and staff as well as their bus, car-pool, and alternate transportation usage. The EPA approved mobile source emissions model, Motor Vehicle Emissions Simulator (MOVES2010a), was used to calculate the emissions from on-road vehicles, and UCF fleet gasoline consumption records were used to calculate the emissions from non-road equipment and on campus UCF fleet vehicles. The results of the UCF mobile source emissions inventory are reported and compared to a recently completed emissions inventory for the entire three-county area in Central Florida.
Show less - Date Issued
- 2011
- Identifier
- CFE0003923, ucf:48704
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003923
- Title
- Trace Contaminant Control: An In-Depth Study of a Silica-Titania Composite for Photocatalytic Remediation of Closed-Environment Habitat Air.
- Creator
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Coutts, Janelle, Yestrebsky, Cherie, Clausen, Christian, Sigman, Michael, Elsheimer, Seth, Wheeler, Raymond, University of Central Florida
- Abstract / Description
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This collection of studies focuses on a photocatalytic oxidation (PCO) system for the oxidation of a model compound, ethanol (EtOH), using an adsorption-enhanced silica-titania composite (STC) as the photocatalyst. Studies are aimed at addressing the optimization of various parameters including light source, humidity, temperature, and possible poisoning events for use as part of a system for gaseous trace contaminant control in closed-environment habitats.The first goal was to distinguish the...
Show moreThis collection of studies focuses on a photocatalytic oxidation (PCO) system for the oxidation of a model compound, ethanol (EtOH), using an adsorption-enhanced silica-titania composite (STC) as the photocatalyst. Studies are aimed at addressing the optimization of various parameters including light source, humidity, temperature, and possible poisoning events for use as part of a system for gaseous trace contaminant control in closed-environment habitats.The first goal was to distinguish the effect of photon flux (i.e., photons per unit time reaching a surface) from that of photon energy (i.e., wavelength) of a photon source on the PCO of ethanol. Experiments were conducted in a bench-scale annular reactor packed with STC pellets and irradiated with either a UV-A fluorescent black light blue lamp (?peak = 365 nm) at its maximum light intensity or a UV-C germicidal lamp (?peak = 254 nm) at three levels of light intensity. The STC-catalyzed oxidation of ethanol was found to follow zero-order kinetics with respect to CO2 production, regardless of the photon source. Increased photon flux led to increased EtOH removal, mineralization, and oxidation rate accompanied by lower intermediate concentration in the effluent. The oxidation rate was higher in the reactor irradiated by UV-C than by UV-A (38.4 vs. 31.9 nM s-1) at the same photon flux, with similar trends for mineralization (53.9 vs. 43.4%) and photonic efficiency (63.3 vs. 50.1 nmol CO2 (&)#181;mol photons-1). UV-C irradiation also led to decreased intermediate concentration in the effluent compared to UV-A irradiation. These results demonstrated that STC-catalyzed oxidation is enhanced by both increased photon flux and photon energy.The effect of temperature and relative humidity on the STC-catalyzed degradation of ethanol was also determined using the UV-A light source at its maximum intensity. Increasing temperature from 25(&)deg;C to 65(&)deg;C caused a significant decrease in ethanol adsorption (47.1% loss in adsorption capacity); minimal changes in EtOH removal; and a dramatic increase in mineralization (37.3 vs. 74.8%), PCO rate (25.8 vs. 53.2 nM s-1), and photonic efficiency (42.7 vs. 82.5 nmol CO2 (&)#181;mol photons-1); as well as a decrease in intermediate acetaldehyde (ACD) evolution in the effluent. By elevating the reactor temperature to 45(&)deg;C, an ~32% increase in photonic efficiency was obtained over the use of UV-C irradiation at room temperature. Increasing the reactor temperature also allowed for increased energy usage efficiency by utilizing both the light and heat energy of the UV-A light source. Higher relative humidity (RH) also caused a significant decrease (16.8 vs. 6.0 mg EtOH g STC-1) in ethanol adsorption and dark adsorption 95% breakthrough times (48.5 vs.16.8 hours). Trends developed for ethanol adsorption correlated well with studies using methanol as the target VOC on a molar basis. At higher RH, ethanol removal and ACD evolution were increased while mineralization, PCO rate, and photonic efficiency were decreased. These studies allowed for the development of empirical formulas to approximate EtOH removal, PCO rate, mineralization, and ACD evolution based on the parameters (light intensity, temperature, and RH) assessed.Poisoning events included long-term exposure to low-VOC laboratory air and episodic spikes of either Freon 218 or hexamethylcyclotrisiloxane. To date, all poisoning studies have shown minimal (0-6%) decreases in PCO rates, mineralization, and minimal increases in ACD evolution, with little change in EtOH removal. These results show great promise for this technology as part of a trace contaminant control system for niche applications such as air processing onboard the ISS or other new spacecrafts.
Show less - Date Issued
- 2013
- Identifier
- CFE0005092, ucf:50741
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005092
- Title
- Novel Fuel-producing Fungi and Methodologies for Increasing Fuel Production.
- Creator
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Wang, Yuemin, Harper, James, Bridge, Candice, Frazer, Andrew, Beazley, Melanie, Blair, Richard, University of Central Florida
- Abstract / Description
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An endophytic fungus Hypoxylon sp. (BS15) has recently been isolated and found to produce volatile organic compounds (VOCs) that have potential relevance as hydrocarbon fuels. In the work described here, the traditional refined carbohydrate (e.g., sucrose) diet source was replaced by simple sugars produced using a solvent free green chemistry mechanocatalytic method involving ball milling in the solid. BS15 is able to grow on this degraded cellulose as well as the more traditional potato...
Show moreAn endophytic fungus Hypoxylon sp. (BS15) has recently been isolated and found to produce volatile organic compounds (VOCs) that have potential relevance as hydrocarbon fuels. In the work described here, the traditional refined carbohydrate (e.g., sucrose) diet source was replaced by simple sugars produced using a solvent free green chemistry mechanocatalytic method involving ball milling in the solid. BS15 is able to grow on this degraded cellulose as well as the more traditional potato dextrose broth. The volatile compounds produced from both media were largely the same. Unfortunately, it is observed that long term in vitro growth of BS15 results in diminished VOC production. The VOC production was partially restored by cultivating BS15 in growth media containing finely ground woody tissue from the original host plant (Taxodium distichum). Extracts from this woody tissue were made by sequentially extracting with dichloromethane, methanol, and water with a goal of isolating VOC production modulators. Both the dichloromethane and water extracts place on bio-mimicking filter paper were found to modulate VOC production, while the methanol extract had no significant impact. Surprisingly, the woody tissue remaining after exhaustive extraction also acted as a VOC production modulator when combined with the growth media, with noticeable changes in the production of four compounds. This woody tissue also induced production of two compounds not observed in the original BS15 extract, and their changes are inheritable. Remarkably filter paper had the same modulating effect as exhaustively extracted woody tissue, suggesting the modulation was partially due to cellulose degradation products. Extraction of the maximum amounts of VOCs is desirable and here a comparison of solid phase extraction (SPE) and solid phase micro-extraction (SPME) techniques is made. This comparison involves two endophytes, BS15C and Streptomyces ambofaciens (SA 40053). The SPE technique is more effective in retaining compounds having lower vapor pressures and higher boiling points with nearly three to five times more VOC mass obtained versus SPME.
Show less - Date Issued
- 2019
- Identifier
- CFE0007552, ucf:52598
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007552