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Seasonal variation of Polycyclic Aromatic Hydrocarbons in the Atmosphere in Kaohsiung CoastZeng, Kun-Yan 27 August 2008 (has links)
A high-volume air sampler (PS-1) was used to measure the
concentrations of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere
of Kaohsiung coast, PAHs diagnostic ratios,Hierarchical Cluster Analysis (HCA)
and Principal Component Analysis (PCA) were employed to determine the
potential sources of PAHs.
The results show that the lowest concentrations of PAHs occurred in May
(2.62 ngm-3), while the highest occurred in December (36.4 ngm-3). The
nighttime concentrations of PAHs are higher than daytime with average night /
day ratio of 1.65. The PAHs was more distributed in gas phase with
proportions between 64.1 to 93.7 %. The 2, 3-Ring PAHs were mostly present
in the gaseous phase (96.2 and 96.5 % respectively), 4-Ring also present
dominantly in the gaseous phase (73.0 %), 5-Ring present mostly in the
particle phase (80.2 %), 6, 7-Ring PAHs were mostly present in particulate
phase (97.4 and 97.7 % respectively). During the Ghost Festiva and Asian
dust storm events, atmospheric concentrations of PAHs and PAHs/TSP ratios
were both found increased.
It is found that gaseous and particulate PAHs correlate negatively with
ambient temperature(r=-0.62, -0.57).
Results from analyses of diagnostic ratios, HCA and PCA, the major
sources of pollution include gasoline, diesel exhaust and industrial emission.
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Synthesis of polycyclic aromatics having unusual molecular architectures via cascade cyclization reactions of enyne-allenesWang, Yu-Hsuan, January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xiv, 240 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 95-104).
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Polycyclic aromatic hydrocarbons (PAHs) : degradation and fungal biomass (ergosterol) in sediment with added nitrogen /Osama, Mohammad. January 2009 (has links)
Thesis (M.S.)--Youngstown State University, 2009. / Includes bibliographical references (leaves 63-68). Also available via the World Wide Web in PDF format.
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Effect of Pleurotus ostreatus on bioremediation of PAH contaminated river sediment /Gacura, Matthew D. January 2009 (has links)
Thesis (M.S.)--Youngstown State University, 2009. / Includes bibliographical references (leaves 38-42). Also available via the World Wide Web in PDF format.
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Spectroscopic and chromatographic study of selective fluorescence quenchers of polycylcic aromatic hydrocarbons (PAHS)Mao, Chunfeng, January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 101-107). Also available on the Internet.
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Spectroscopic and chromatographic study of selective fluorescence quenchers of polycylcic aromatic hydrocarbons (PAHS) /Mao, Chunfeng, January 2003 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 101-107). Also available on the Internet.
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Polycyclic aromatic hydrocarbon desorption mechanisms from manufactured gas plant site samplesPoppendieck, Dustin Glen 28 August 2008 (has links)
Not available / text
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Aromatic Hydrocarbon Sampling and Extraction From Flames Using Temperature-swing Adsorption/Desorption ProcessesChan, Hei Ka Tim 23 August 2011 (has links)
The measurement of Polycyclic Aromatic Hydrocarbons (PAHs) in flames is essential for the understanding of soot formation. In comparison to conventional aromatics-sampling techniques, a new technique was proposed that involves fewer manual operations and no hazardous extraction solvents. Apparatus and experimental procedures of the newly proposed adsorptive-sampling and desorptive-extraction technique for aromatic-hydrocarbon measurements were established in this study. The capabilities and limitations of this new technique were assessed in terms of limits of detection, sampling locations and data repeatability.
The accuracy of this technique was also evaluated. Aromatic-hydrocarbon species concentrations were measured in laminar co-flow diffusion flames of ethylene (C2H4) and synthetic paraffinic kerosene (SPK). The results obtained from the ethylene flame were compared to its numerical simulation, with the goal of achieving agreement within an order of magnitude. The differences between simulated values and experimental measurements, along with the limitations of the technique, were used as an indication of the accuracy of the technique.
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Aromatic Hydrocarbon Sampling and Extraction From Flames Using Temperature-swing Adsorption/Desorption ProcessesChan, Hei Ka Tim 23 August 2011 (has links)
The measurement of Polycyclic Aromatic Hydrocarbons (PAHs) in flames is essential for the understanding of soot formation. In comparison to conventional aromatics-sampling techniques, a new technique was proposed that involves fewer manual operations and no hazardous extraction solvents. Apparatus and experimental procedures of the newly proposed adsorptive-sampling and desorptive-extraction technique for aromatic-hydrocarbon measurements were established in this study. The capabilities and limitations of this new technique were assessed in terms of limits of detection, sampling locations and data repeatability.
The accuracy of this technique was also evaluated. Aromatic-hydrocarbon species concentrations were measured in laminar co-flow diffusion flames of ethylene (C2H4) and synthetic paraffinic kerosene (SPK). The results obtained from the ethylene flame were compared to its numerical simulation, with the goal of achieving agreement within an order of magnitude. The differences between simulated values and experimental measurements, along with the limitations of the technique, were used as an indication of the accuracy of the technique.
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Effects-Driven Fractionation of Heavy Fuel Oil to Isolate Compounds Toxic to Trout EmbryosBornstein, Jason 09 August 2012 (has links)
Heavy Fuel Oil (HFO) is a petroleum product and emerging contaminant used as fuel by cargo ships, cruise liners, and oil tankers. As a high-frequency, low volume commodity shipped by pipeline, train, truck, and ship, it is at high risk for small-scale spills in terrestrial, aquatic, and marine environments. There are few reports characterizing HFOs and quantifying the contaminants therein, but previous studies have shown that the most toxic classes of compounds in petroleum products are polycyclic aromatic hydrocarbons (PAHs). This project seeks to address that by analyzing HFO 7102, the specific HFO spilled in Wabamun Lake, Alberta in August 2005.
Through an Effects-Driven Fractionation and Analysis, HFO 7102 was successively fractionated by physical and chemical means. First, a low-temperature vacuum distillation separated the oil into three fractions by volatility. The most toxic of these (lowest median toxic concentration, or LC50), F3, underwent a series of solvent extractions to remove asphaltenes and waxes. The remaining PAH-rich extract (F3-1) was further separated using open column chromatography into non-polar, mid-polar, and polar fractions with groupings approximately by number of aromatic rings. At each stage, fractions and sub-fractions were characterized by GC-MS for compositional analysis and bioassays were conducted with rainbow trout embryos. In this fashion, toxicity thresholds were developed for all fractions and the components of HFO 7102 associated with toxicity were identified and quantified.
The F3 fraction was six times more toxic than the whole oil. While the wax fraction (F3-2) was shown to be non-toxic, the remaining PAH-rich extract (F3-1) accounted for all of the toxicity in F3. Future work may be done to determine the relative toxicity of the last fractions generated and identify a range of PAH responsible for fish toxicity. It is expected that the F3-1-2 fraction will be most toxic, as it contains nearly all of the three-ring and most of the four-ring PAH. These size classes of PAH have been associated with chronic toxicity to fish embryos in studies of crude oil. Further separations may be attempted to identify a more specific range of toxic compounds, such as by degree of alkylation. / Thesis (Master, Chemistry) -- Queen's University, 2012-07-31 11:31:15.238
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