North American petroleum refineries use landfarming to dispose of hydrocarbon-containing wastes for bioremediation by indigenous soil microorganisms. In this study, we isolated PAH-degrading bacteria from landfarm soil by enrichment with hydrocarbon-containing effluent. One isolate, Arthrobacter sp. UG50, was capable of using phenanthrene and anthracene as sole carbon sources. The strain degraded phenanthrene (200 mg/L) within 24 h in pure culture at high cell density (10e8 cells/mL). Anthracene (50 mg/L) was slowly degraded, with 29% degraded within 21 days. The strain could not use naphthalene, pyrene, chrysene or benzo(a)pyrene as sole carbon sources, but could degrade pyrene (50 mg/L) cometabolically when phenanthrene was provided. Anthracene degradation (50 mg/L) was enhanced by phenanthrene, with 100% degraded within 6 days. The addition of strain UG50 to petroleum sludge in baffled flasks increased total hydrocarbon degradation and degradation of low concentrations of fluorene, phenanthrene, pyrene and chrysene compared to flasks with limited aeration or containing sludge alone. / NOVA Chemicals and the Ontario Centres of Excellence

The accumulation of persistent contaminants is a significant issue for the health of aquatic environments. This study aims to determine the effects of polycyclic aromatic hydrocarbons (PAH) on the stress response of fish by monitoring plasma cortisol levels and the expression of key hypothalamic-pituitary-interrenal (HPI) stress axis regulators. Injection of benzo(a)pyrene (BaP), a ubiquitous PAH, induced a differential dose- and time-dependentcortisol response in rainbow trout and brown bullhead. BaP exposure also elicited a species-specific transcriptional response at all levelsof the HPI axis.Similarly, the HPI axis response to a standardized emersionstressor revealed species-specific differences. In the field, exposure of different brown bullhead populations to sediment with complex PAH mixtures did not consistently affect cortisol levels and providedno evidence of genetic adaptation of the stress response. Thus, future studies are needed to bridge the gap in our understanding between the laboratory and field effects of PAHs on the stress response of fish.

The field of organic electronics has received much attention over the last few years, and engineering of organic crystals to grow with pi-electron systems arranged in a face-to-face motif has been shown to be beneficial in electronic devices. The effects of combining aromatic and perfluorinated aromatic derivatives have shown that the intramolecular stacking pattern can be changed from an edge-to-face arrangement to that of a face-to-face motif. Before the work described herein, there were no reported studies of the supramolecular behavior of fused polycyclic aromatic compounds with partial peripheral fluorination, inducing the desired face-to-face behavior. This is the main focus of the thesis. Furthermore, by exploiting the interactions between the fluorinated and non-fluorinated faces of the molecule, columnar liquid crystalline behavior can be achieved through variations of the alkyl substituents on the molecule.

The long-term fate of hydrocarbons in the Gulf of Mexico (GOMx) following the 2010 Deepwater Horizon oil spill has yet to be fully characterized. Elemental (% C and % N), stable isotopes (δ13Corganic), and polycyclic aromatic hydrocarbon (PAH) molecular signatures were investigated in shelf and slope sediments collected in October 2010 and 2011 to gain insight into processes affecting the distribution and fate of spilled Macondo oil. Particulate organic carbon (POC) ranged between 1.55 and 2.22 wt. % in 2010 and 0.55 and 2.06 % in 2011 while the corresponding δ13Corganic ranges were from -23.37 to -20.77 ‰ (vs. PDB) in 2010, and -22.68 to -20.75 ‰ (vs. PDB) in 2011. Ranges of total polycyclic aromatic hydrocarbon (TPAH) concentrations were from 72.57 to 7,543.53 ng/g in 2010 and 25.55 to 16,582.77 ng/g in 2011. The range of measured values represented significant deviations from previous background measurements. This provided the basis for concluding that the Macondo spill altered the “background” organic carbon and hydrocarbon signature, that Macondo oil has weathered and/or biodegraded in the year following the spill, and that a significant spatial trend of hydrocarbons extended from the Macondo well across the northern GOMx in October 2010 and 2011.

Graphene is a two-dimensional sp2 hybridized carbon lattice that is also the fundamental building block of graphite. Graphene has attracted significant interest recently due to its distinctive electrical, optical and mechanical properties. These properties have spurred research directed at modifying graphene for use in a variety of electronic, optoelectronic, and sensor technologies. However, before graphene can be used in products, it is necessary to find methods to tune, modify, grow and integrate graphene features while substantially boosting device performance and maintaining current processing compatibility and ease of integration with existing manufacturing infrastructure. This dissertation focuses on developing techniques for controllably doping the graphene layer through scalable, industry friendly and simple chemical doping; using self-assembled monolayer compounds, photo-acid and photo-base generators, polymers and metal-organic species. We have, in fact, demonstrated simple p-n junctions fabricated in this manner. Characteristic I-V curves indicate the superposition of two separate Dirac points from the p and n regions, confirming an energy separation of neutrality points within the complementary regions; Raman studies of these methods have shown that these processes result in extremely low defect levels in the graphene. Our simple methods for producing patterned doping profiles in graphene films and devices open up a variety of new possibilities for forming complex doping profiles in a simple manner in graphene. This work can enable rapid testing, such as controlled work function tuning, complex doping profiles and simple post-fabrication tuning, of concepts for graphene that may be useful in both interconnect and transparent conductor applications. In addition to graphene doping, we also investigated approaches to the synthesis of few-layer graphene flakes, since current techniques still produce inferior materials. Exfoliation of Graphene Sheets by an Electron Donor Surfactant was demonstrated to generate few-layers graphene flakes that rival the electrical quality of reduce graphene-oxide (rGO) flakes. Last but not least, Diels-Alder adducts on silica were explored as a controllable carbon precursor for pristine graphene; these allow for a rational direct-growth-of-graphene-on-surface reaction mediated by copper catalyst, without the use of flammable precursors, such as methane, that are used in current methods of chemical vapor deposition synthesis of graphene.

In der vorliegenden Arbeit wurde die elektronische Struktur verschiedener undotierter und mit Alkalimetallen beziehungsweise 2,3,5,6-Tetrafluoro-7,7,8,8-tetracyanoquinodimethan (F 4 TCNQ) dotierter, polyzyklischer aromatischer Kohlenwasserstoffe (PAK) untersucht. Diese Untersuchungen waren motiviert durch verschiedene Veröffentlichungen in denen supraleitendes Verhalten an unterschiedlichen alkalimetalldotierten PAK beschrieben wurde. Erste Studien erfolgten an undotiertem 1,2:8,9-Dibenzopentacen (DBP) und Pentacen unter Nutzung von Photoelektronenspektroskopie (PES), Elektronenenergieverlustspektroskopie (EELS) und Dichtefunktionaltheorie (DFT). Die spektroskopischen Methoden zeigten für beide Materialien eine große Ähnlichkeit der elektronischen Zustände, vor allem im niederenergetischen Bereich, welche durch die theoretischen Ergebnisse bestätigt wurde. Die elektronische Ähnlichkeit beider Materialien ist im starken Gegensatz zu dem in der Literatur bei Dotierung beobachteten Verhalten, bei dem Pentacen zum Mott-Isolator wird, während DBP Supraleitung zeigt. Weitere Untersuchungen erfolgten an Picen und Coronen. Bandstrukturrechnungen zeigten, dass Picen vermutlich ein stark korreliertes Elektronensystem besitzt. Neben dem mit PES ermittelten Ionisationspotential und der Austrittsarbeit waren auch die mit EELS gemessenen optischen Bandlücken der beiden Materialien sehr ähnlich. Unterschiede zeigten sich hingegen vor allem in der Dichte der gemessenen Zustände von Picen und Coronen am Ferminiveau. Bei der Untersuchung der elektronischen Eigenschaften von mit Kalium-dotierten Picen und Coronen wurde trotz der erfolgreichen Dotierung in keinem der untersuchten Filme eine Zustandsdichte am Ferminiveau beobachtet somit wurde auch keiner der untersuchten Filme metallisch. Dasselbe Verhalten konnte auch für Natrium-dotierte Filme beobachtet werden. Eine Diskussion dieses Ergebnisses, welches im Gegensatz zu der von anderen Gruppen in dotierten Molekülen beobachteten Supraleitung steht, erfolgte im Hinblick auf die Bildung unterschiedlich dotierter Phasen, Elektron-Phonon-Kopplung, der Formierung von Bi-Polaronen und Korrelationseffekten. Für ein weitergehendes Verständnis der dotierungsinduzierten elektronischen Eigenschaften in den untersuchten Molekülen wurden diese nicht nur mit Alkalimetallen, sondern teilweise auch mit elektronenziehenden Molekülen wie F 4 TCNQ interkaliert. Dabei entstanden Kristalle verschiedener Ladungstransfersalze. Eine ausführliche Charakterisierung erfolgte für Picen/F 4 TCNQ-Kristalle, welche im Rahmen dieser Arbeit zum ersten Mal hergestellt und untersucht wurden. Dabei wurde zunächst deren Kristallstruktur mit Röntgendiffraktometrie (XRD) bestimmt. Eine Abschätzung der Größe des Ladungstransfers innerhalb der Molekülpaare aus Picen/ F 4 TCNQ erfolgte über Infrarot- und Bindungslängendaten, die auf diese Weise gefunden Werte wurden zusätzlich durch DFT-Rechnungen untermauert. Transportmessungen zeigten außerdem, dass die hergestellten Kristalle entlang ihrer Hauptwachstumsrichtung Isolatoren sind. Die Untersuchung der elektronischen Eigenschaften wurde mit EELS und PES an Picen/ F 4 TCNQ -Dünnfilmen durchgeführt, welche durch die Verdampfung der Einkristalle hergestellt wurden. Die Molekülpaare zeigen einen Ladungstransfer, der neue elektronische Anregungen im Niederenergiebereich der mit EELS gemessenen Verlustfunktion hervorruft. Im weiteren Verlauf der Arbeit erfolgte eine Diskussion bezüglich des Charakters und der Lokalisierung dieser neuen Anregungen. Bei den PES-Messungen zeigte sich der Ladungstransfer durch energetische Verschiebungen in den gemessen Rumpfniveauspektren sowie durch im Vergleich zu den reinen Materialien deutlich veränderte Ionisationspotentiale. Trotz des erfolgreichen Ladungstransfers und der damit verbundenen Füllung von unbesetzten Zuständen mit Elektronen in F 4 TCNQ wurde jedoch in den Valenzbandspektren keine Emission am Ferminiveau beobachtet. DFT-Rechnungen ermöglichten schließlich Aussagen über den Charakter des Ladunstransfers und die daraus resultierende, fehlende Zustandsdichte am Ferminiveau.

Non-competitive adsorption of polycyclic aromatic hydrocarbons (PAHs) from water onto activated carbon was studied alongside the performance of CO2-activated petroleum coke as a low-cost adsorbent. PAH adsorption was a two-stage process: a short, fast initial period followed by a long, slow period corresponding to the intra-particle diffusion of PAH molecules in macropores and micropores. The adsorption capacity was determined by total surface area accessible to PAH and the availability of active surface chemical groups. The positive dependence of adsorption capacity on surface oxygen groups and temperature was observed, suggesting a chemical nature of PAH adsorption. The interaction between PAH-activated carbon was however, weak and energetically similar to that of hydrogen bonds. Overall, PAH adsorption was an exothermic process that combined physisorption and chemisorption. CO2-activated petroleum coke had a greater SSA-normalized capacity than coal-derived commercial activated carbon (0.26 vs. 0.19 mg/m2). The capacity was significantly increased by post-oxidation to 0.62 mg/m2.

Non-competitive adsorption of polycyclic aromatic hydrocarbons (PAHs) from water onto activated carbon was studied alongside the performance of CO2-activated petroleum coke as a low-cost adsorbent. PAH adsorption was a two-stage process: a short, fast initial period followed by a long, slow period corresponding to the intra-particle diffusion of PAH molecules in macropores and micropores. The adsorption capacity was determined by total surface area accessible to PAH and the availability of active surface chemical groups. The positive dependence of adsorption capacity on surface oxygen groups and temperature was observed, suggesting a chemical nature of PAH adsorption. The interaction between PAH-activated carbon was however, weak and energetically similar to that of hydrogen bonds. Overall, PAH adsorption was an exothermic process that combined physisorption and chemisorption. CO2-activated petroleum coke had a greater SSA-normalized capacity than coal-derived commercial activated carbon (0.26 vs. 0.19 mg/m2). The capacity was significantly increased by post-oxidation to 0.62 mg/m2.

Sites contaminated with polyaromatic hydrocarbons (PAHs) pose serious health and safety risks to the surrounding environment due to their toxicity, persistence and accumulation in the environment. Because certain members of this class have been demonstrated to be both carcinogenic and mutagenic, PAHs are considered as environmental priority pollutants (US EPA). The studies in this thesis provide an efficient, economical and environmentally benign technique for the remediation of PAH contaminated soil/sediment by means of PAH mobilization with surfactant followed with a catalytic hydrogenation in supercritical carbon dioxide (scCO2). / Catalytic hydrogenation of naphthalene, acenaphthylene, ancenaphthene, anthracene, phenanthrene, chrysene and benzo[a]pyrene over alumina supported palladium (5% Pd0/gammaAl2O3) commercial catalyst were investigated in either a batch reaction mode or a continuous reaction system in H2-scCO2 (∼5% v/v). The hydrocarbon compounds were efficiently reduced to their corresponding fully saturated polycyclic hydrocarbon homologs with mild conditions of temperature (90°C) and pressure (60 psi H2 or 3000 psi H2-scCO2). The bacterial reverse mutation assay demonstrated that both the fully and partially hydrogenated products of chrysene and benzo[a]pyrene were devoid of mutagenic activity. / A laboratory study was conducted on the surfactant-assisted mobilization of PAH compounds combined with reagent regeneration and detoxification steps to generate innocuous products. Five minutes of ultrasonication of field contaminated soil with a 3% (w/v) surfactant suspension mobilized appreciable quantities of all PAH compounds. Formulating the Brij 98 surfactant in 0.1 M phosphate buffer (pH 8.0) mobilized the largest quantities of PAH compounds and the recovery of surfactant (>90%) but soil residues exceeded permissible maxima for five- and six-ring analytes. Five successive washes were required to reduce the residual fraction to permissible levels. The mobilized PAH compounds were then detoxified at line by catalytic hydrogenation in a 5% H2-scCO2 (v/v) atmosphere. / New palladium hydrogenation catalysts were fabricated in the laboratory with specific processes on various supports. The hydrogenation of phenanthrene and benzo[a]pyrene in a fixed bed micro reactor demonstrated that the catalyst that was fabricated from organosoluble precursor loaded on aluminum oxide (2.5% Pd0/gammaAl2O3) was four times more efficient than the commercial catalyst that was used for PAH hydrogenations.

Hydramycin is an antitumor antibiotic isolated from Streptomyces violaceus. It is a pyranoanthraquinone-type antitumor agent that has shown broad-spectrum activity against a variety of human-derived cancer cell lines. Among tumors evaluated at the National Cancer Institute (lung, colon, melanoma, breast and prostate), GI50s were <10−10 M in the NCI's 60-cell-line panel. We embarked on the synthesis and evaluation of a simplified congener 2-(1-hydroxy-1-(oxiran-2-yl)ethyl)-4H-naphtho[2,3-h]chromene-4,7,12-trione(17), which would facilitate synthesis while retaining the potent activity. Hydramycin has two chiral centers, and our goal is to design and synthesize all the possible enantiomers (four in total) for the congener of hydramycin 17 in order to ascertain which of the enantiomers is responsible for the observed antitumor activity. The use of enantiospecific techniques such as the Sharpless epoxidation was initially tried to introduce the chiral centers at a later stage during the multi-step synthesis and obtain the required pure enantiomers. Due to some limitations observed with this technique and many other asymmetric epoxidation techniques which utilize very substrate-specific ligands, we then modified the synthetic scheme to use another procedure, the Sharpless asymmetric dihydroxylation in order to obtain two of the pure enantiomers of this congener of hydramycin. The other two enantiomers are selectively obtained using the Sharpless asymmetric dihydroxylation procedure via cyclic sulfate intermediates, followed by a modified irreversible Payne rearrangement procedure. These routes then allowed us to obtain separately all four stereoisomers, each having more than 90% ee as determined on chiral columns with HPLC. The four stereoisomers have been fully characterized and will then be tested separately to ascertain which of the isomers is responsible for the observed antitumor activity.