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Polycyclic Aromatic Hydrocarbon Solute Probes: Effect of Solvent Polarity on the Ovalene and Benzo[ghi]perylene Fluorescence Emission Fine Structures

Description: Article on polycyclic aromatic hydrocarbon solute probes and the effect of solvent polarity on the ovalene and benzo[ghi]perylene fluorescence emission fine structures.
Date: 1988
Creator: Waris, Riaz; Rembert, Michael A.; Sellers, David M.; Acree, William E. (William Eugene); Street, Kenneth W.; Poole, Colin F. et al.
Partner: UNT College of Arts and Sciences

Polycyclic-Aromatic-Hydrocarbon-Induced Alterations in the Physio-Chemical Characteristics of Escherechia Coli Dexyribonucleic Acid

Description: Prior to 1965 the interactions of polycyclic aromatic hydrocarbons with DNA (Deoxyribonucleic acid) had been but moderately studied. It was concluded that, although a controversy existed, an apparent interaction occurred between DNA and certain aromatic hydrocarbon molecules and that the interaction was not an artifact of the reaction system.
Date: August 1969
Creator: Chapel, J. Frederick (James Frederick)
Partner: UNT Libraries

Polycyclic Aromatic Hydrocarbon Solute Probes. Part 6: Effect of Dissolved Oxygen and Halogenated Solvents on the Emission Spectra of Select Probe Molecules

Description: Article on polycyclic aromatic hydrocarbon solute probes and the effect of dissolved oxygen and halogenated solvents on the emission spectra of select probe molecules.
Date: 1990
Creator: Tucker, Sheryl A. (Sheryl Ann); Cretella, Lisa E.; Waris, Riaz; Street, Kenneth W.; Acree, William E. (William Eugene) & Fetzer, John Charles, 1953-
Partner: UNT College of Arts and Sciences

Spectrofluorometric and Solubility Studies of Polycyclic Aromatic Hydrocarbons in Hydrogen Bonded Binary Solvent Mixtures

Description: The purpose of this dissertation is to investigate the behavior of polycyclic aromatic hydrocarbons (PAHs) in binary solvent systems and determine and/or develop predictive mathematical expressions for describing solutions in which hydrogen-bonding occurs.
Date: May 1997
Creator: Powell, Joyce R., 1968-
Partner: UNT Libraries

Novel transcriptome assembly and comparative toxicity pathway analysis in mahi-mahi (Coryphaena hippurus) embryos and larvae exposed to Deepwater Horizon oil

Description: This article establishes the de novo transcriptomic database from the embryos and larvae of mahi-mahi exposed to water accommodated fractions (HEWAFs) of two Deepwater Horizon oil types (weathered and source oil) in an effort to advance understanding of the molecular aspects involved during specific toxicity responses.
Date: March 15, 2017
Creator: Xu, Elvis Genbo; Mager, Edward M.; Grosell, Martin; Hazard, E. Starr; Hardiman, Gary & Schlenk, Daniel
Partner: UNT College of Arts and Sciences

Selective Fluorescence Quenching to Discriminate Between Alternant and Non-alternant Polycyclic Aromatic Hydrocarbons: Acephenanthrylene Derivatives as Exceptions to the Nitromethane Quenching Rule

Description: Article on selective fluorescence quenching to discriminate between alternant and non-alternant polycyclic aromatic hydrocarbons and acephenanthrylene derivatives as exceptions to the nitromethane quenching rule.
Date: September 1, 1994
Creator: Tucker, Sheryl A. (Sheryl Ann); Griffin, Jason M.; Acree, William E. (William Eugene); Mulder, Patrick P. J.; Lugtenburg, Johan & Cornelisse, Jan
Partner: UNT College of Arts and Sciences

Polycyclic Aromatic Hydrocarbon Solute Probes. Part 11: Unusual Solvent-Modulated Fluorescence Emission Behavior of 1-Methylcoronene and Select Dimethylcoronenes in Nonelectrolyte Solvents

Description: Article on polycyclic aromatic hydrocarbon solute probes and an unusual solvent-modulated fluorescence emission behavior of 1-methylcoronene and select dimethylcoronenes in nonelectrolyte solvents.
Date: 1995
Creator: Tucker, Sheryl A. (Sheryl Ann); Acree, William E. (William Eugene) & Fetzer, John Charles, 1953-
Partner: UNT College of Arts and Sciences

A Quenchofluorometric Study of Polycyclic Aromatic Hydrocarbons in Molecularly Organized Media

Description: Detection, identification and separation of polycyclic aromatic compounds in environmental samples are of extreme importance since many of these compounds are well known for their potential carcinogenic and/or mutagenic activities. Selective quenching of molecular fluorescence can be utilized effectively to analyze mixtures containing different polycyclic aromatic hydrocarbons. Molecularly organized assemblies are used widely in detection and separation of these compounds mainly because of less toxicity and enhanced solubilization capabilities associated with these media. Feasibility of using nitromethane and the alkylpyridinium cation as selective fluorescence quenching agents for discriminating between alternant versus nonalternant polycyclic aromatic hydrocarbons (PAHs) is critically examined in several molecularly organized micellar solvent media. Fluorescence quenching is used to probe the structural features in mixed micelles containing the various combinations of anionic, cationic, nonionic and zwitterionic surfactants. Experimental results provide valuable information regarding molecular interactions between the dissimilar surfactants.
Date: May 1998
Creator: Pandey, Siddharth
Partner: UNT Libraries

Selective Fluorescence Quenching to Discriminate Between Alternant and Non-alternant Polycyclic Aromatic Hydrocarbons: Acephenanthrylene Derivatives as Exceptions to the Nitromethane Quenching Rule

Description: Article on selective fluorescence quenching to discriminate between alternant and non-alternant polycyclic aromatic hydrocarbons and acephenanthrylene derivatives as exceptions to the nitromethane quenching rule.
Date: September 1994
Creator: Tucker, Sheryl A. (Sheryl Ann); Griffin, Jason M.; Acree, William E. (William Eugene); Mulder, Patrick P. J.; Lugtenburg, Johan & Cornelisse, Jan
Partner: UNT College of Arts and Sciences

Spectrochemical Investigations of Preferential Solvation. Fluorescence Emission Behavior of Select Polycyclic Aromatic Hydrocarbon Solute Probes Dissolved in Mixed Solvents

Description: Article discussing spectrochemical investigations of preferential solvation and fluorescence emission behavior of select polycyclic aromatic hydrocarbon solute probes dissolved in mixed solvents.
Date: October 1993
Creator: Acree, William E. (William Eugene); Tucker, Sheryl A. (Sheryl Ann) & Wilkins, Denise C.
Partner: UNT College of Arts and Sciences

Preparation of flat dendrimers and polycyclic aromatic hydrocarbons connected via 1,3,5-triethynylbenzene core.

Description: Flat dendrimers, consisting of a hexavalent aromatic core and rigid ethynyl units locked in place by ether connections were developed based upon the divergent synthetic method. Alternating functional groups were adopted on each site of the hexa-substituted benzene, in order to avoid undesired cyclization pathways. The flat structures of conjugated dendrimers would allow investigation on the discotic liquid crystal properties. In addition, these ethylnyl dendrimers are expected to show directed energy and electron transfer with a highly conjugated system, and thus are effective in the preparation of photoreactive materials such as electronic sensors or light harvesting materials. Conjugated polycyclic aromatic hydrocarbons, consisting of naphthalene, anthracene, pyrene, and phenanthrene groups connected via 1,3,5-triethynylbenzene cores, were synthesized. These molecules exhibited luminescence properties and the π-complexation with a mercury trifunctional lewis acid are expected to enhance the phosphorescence in the presence of the heavy metal due to the spin-orbit coupling. Besides, owing to the presence of heavy metal atom in the Au (I) complexes linked by s-bonded triethynyltriphenylene luminophore, the phosphorescence occurs from a metal-centered emission. The conjugated organic luminophores have been developed to produce excellent quantum efficiencies, brightness, and long lifetimes.
Date: December 2008
Creator: Jung, Jiyoung
Partner: UNT Libraries

Detecting exposure to environmental organic toxins in individual cells: towards development of a micro-fabricated device

Description: A new method is being developed to quickly screen for the human exposure potential to polycyclic aromatic hydrocarbons (PAHs) and organochlorines (OCs). The development involves two key elements: identifying suitable signals that represent intracellular changes that are specific to PAH and OC exposure, and constructing a device to guide the biological cell growth so that signals from individual cells are consistent and reproducible. We are completing the identification of suitable signals by using synchrotron radiation-based (SR) Fourier-transform infrared (FTIR) spectromicroscopy in the mid-infrared region (4000-400 cm-1). Distinct changes have been observed in the IR spectra after treatment of human cells in culture medium with PAHs and OCs. The potential use of this method for detecting exposure to PAHs and OCs has been tested and compared to a reverse transcription polymerase chain reaction (RT-PCR) assay that quantifies increased expression of the CYP1A1 gene in response to exposu re to PAHs or OCs.
Date: January 10, 1999
Creator: Holman, Hoi-Ying N.; Zhang, Miqin; Goth-Goldstein, Regine; Martin, Michael C.; Russell, Marion; McKinney, Wayne R. et al.
Partner: UNT Libraries Government Documents Department

Gas and Particulate Sampling of Airborne Polycyclic Aromatic Compounds

Description: The denuder surfaces of the gas and particle (GAP) sampler (developed at the Atmospheric Environment Service of Environment Canada) have been modified by coating with XAD-4 resin, using techniques developed at Lawrence Berkeley National Laboratory (LBNL) for the lower capacity integrated organic vapor/particle sampler (IOVPS). The resulting high capacity integrated organic gas and particle sampler (IOGAPS) has been operated in ambient air at 16.7 L min{sup -1} for a 24-hour period in Berkeley, California, USA. Simultaneous measurements were made at the same collection rate with a conventional sampler that used a filter followed by two sorbent beds. Gas and particle partition measurements were determined for 13 polycyclic aromatic hydrocarbons (PAH) ranging from 2-ring to 6-ring species. The IOGAPS indicated a higher particle fraction of these compounds than did the conventional sampler, suggesting that the conventional sampler suffered from 'blow-off' losses from the particles collected on the filter.
Date: October 1, 1995
Creator: Lane, D.A. & Gundel, L.A.
Partner: UNT Libraries Government Documents Department