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Effect of Solvent Polarity and Acidity on Fluorescence Emission Fine Structures of Select Aza-Polynuclear Aromatics and Dibenzo[b,n]perylene Hetero-Atom Derivatives

Description: Article on the effect of solvent polarity and acidity on fluorescence emission fine structures of select aza-polynuclear aromatics and dibenzo[b,n]perylene hetero-atom derivatives.
Date: 1991
Creator: Tucker, Sheryl A. (Sheryl Ann); Acree, William E. (William Eugene); Tanga, Mary J.; Fetzer, John Charles, 1953-; Tokita, Sumio; Hiruta, Kimihiro et al.
Partner: UNT College of Arts and Sciences

Polycyclic Aromatic Nitrogen Heterocycles. Part 2: Effect of Solvent Polarity on the Fluorescence Emission Fine Structure of Three Azapyrene Compounds

Description: Article on polycyclic aromatic nitrogen heterocycles and the effect of solvent polarity on the fluorescence emission fine structure of three azapyrene compounds.
Date: 1991
Creator: Tucker, Sheryl A. (Sheryl Ann); Acree, William E. (William Eugene) & Tanga, Mary J.
Partner: UNT College of Arts and Sciences

Spectroscopic Properties of Polycyclic Aromatic Compounds: Examination of Nitromethane as a Selective Fluorescence Quenching Agent for Alternate Polycyclic Aromatic Nitrogen Hetero-Atom Derivatives

Description: Article on the spectroscopic properties of polycyclic aromatic compounds and an examination of nitromethane as a selective fluorescence quenching agent for alternant polycyclic aromatic nitrogen hetero-atom derivatives.
Date: 1992
Creator: Tucker, Sheryl A. (Sheryl Ann); Acree, William E. (William Eugene); Tanga, Mary J.; Tokita, Sumio; Hiruta, Kimihiro & Langhals, Heinz
Partner: UNT College of Arts and Sciences

Polycyclic Aromatic Hydrocarbon Solute Probes. Part 8: Evaluation of Additional Naphthacene and Perylene Derivatives as Possible Solvent Polarity Probe Molecules

Description: Article on polycyclic aromatic hydrocarbon solute probes and an evaluation of additional naphthacene and perylene derivatives as possible solvent polarity probe molecules.
Date: 1991
Creator: Tucker, Sheryl A. (Sheryl Ann); Teng, I.-Lih; Acree, William E. (William Eugene) & Fetzer, John Charles, 1953-
Partner: UNT College of Arts and Sciences

Spectroscopic Properties of Polycyclic Aromatic Hydrocarbons: Effect of Solvent Polarity on the Fluorescence Emission Behavior of Select Fluoranthene, Fluorenochrysene, Indenochrysene, and Indenopyrene Derivatives

Description: Article on the spectroscopic properties of polycyclic aromatic hydrocarbons and the effect of solvent polarity on the fluorescence emission behavior of select fluoranthene, fluorenochrysene, indenochrysene, and indenopyrene derivatives.
Date: 1991
Creator: Tucker, Sheryl A. (Sheryl Ann); Acree, William E. (William Eugene); Cho, Bongsup P.; Harvey, Ronald G. & Fetzer, John Charles, 1953-
Partner: UNT College of Arts and Sciences

Polycyclic Aromatic Hydrocarbon Solute Probes. Part 3: Fluorescence Emission Spectra of Pyrene, Ovalene, Benzo[ghi]perylene, and Coronene Dissolved in Liquid Tetrabutylammonium Sulfonate Salts

Description: Article on polycyclic aromatic hydrocarbon solute probes and fluorescence emission spectra of pyrene, ovalene, benzo[ghi]perylene, and coronene dissolved in liquid tetrabutylammonium sulfonate salts.
Date: 1989
Creator: Tucker, Sheryl A. (Sheryl Ann); Acree, William E. (William Eugene); Street, Kenneth W. & Fetzer, John Charles, 1953-
Partner: UNT College of Arts and Sciences

Polycyclic Aromatic Hydrocarbon Solute Probes. Part 7: Evaluation of Additional Coronene Derivatives as Possible Solvent Polarity Probe Molecules

Description: Article on polycyclic aromatic hydrocarbon solute probes and the evaluation of additional coronene derivatives as possible solvent polarity probe molecules.
Date: 1990
Creator: Acree, William E. (William Eugene); Tucker, Sheryl A. (Sheryl Ann); Zvaigzne, Anita I.; Street, Kenneth W.; Fetzer, John Charles, 1953- & Grützmacher, Hans-Friedrich
Partner: UNT College of Arts and Sciences

Polycyclic Aromatic Hydrocarbon Solute Probes. Part 5: Fluorescence Spectra of Pyrene, Ovalene, Coronene, and Benzo[ghi]perylene Dissolved in Liquid Alkylammonium Thiocyanate Organic Salts

Description: Article on polycyclic aromatic hydrocarbon solute probes and fluorescence spectra of pyrene, ovalene, coronene, and benzo[ghi]perylene dissolved in liquid alkylammonium thiocyanate organic salts.
Date: February 24, 1989
Creator: Street, Kenneth W.; Acree, William E. (William Eugene); Fetzer, John Charles, 1953-; Shetty, Prabhakara H. & Poole, Colin F.
Partner: UNT College of Arts and Sciences

Polycyclic Aromatic Hydrocarbon Solute Probes. Part 4: Effect of Solvent Polarity on the Fluorescence Emission Fine Structures of Select Pyrene and Pentaphene Derivatives

Description: Article on polycyclic aromatic hydrocarbon solute probes and the effect of solvent polarity on the fluorescence emission fine structures of select pyrene and pentaphene derivatives.
Date: January 1989
Creator: Waris, Riaz; Street, Kenneth W.; Acree, William E. (William Eugene) & Fetzer, John Charles, 1953-
Partner: UNT College of Arts and Sciences

Spectroscopic Properties of Polycyclic Aromatic Compounds. Part 3: Fluorescence Emission and Quenching Behavior of Periodic Table Group 16 Hetero-Atom Derivatives

Description: Article on the spectroscopic properties of polycyclic aromatic compounds and the fluorescence emission and quenching behavior of periodic table group 16 hetero-atom derivatives.
Date: 1993
Creator: Tucker, Sheryl A. (Sheryl Ann); Acree, William E. (William Eugene); Zander, Maximilian; Demerseman, Pierre & Buisson, Jean-Pierre
Partner: UNT College of Arts and Sciences

Polycyclic Aromatic Nitrogen Heterocycles. Part 3: Effect of Solvent Polarity and Solvent Acidity on the Fluorescence Emission Behavior of Select Azapyrenes and Phenanthroisoquinolines

Description: Article on polycyclic aromatic nitrogen heterocycles and the effect of solvent polarity and solvent acidity on the fluorescence emission behavior of select azapyrenes and phenanthroisoquinolines.
Date: 1991
Creator: Tucker, Sheryl A. (Sheryl Ann); Acree, William E. (William Eugene) & Tanga, Mary J.
Partner: UNT College of Arts and Sciences

Determination of Uranium by Fluorescence

Description: Abstract: "The uranium content of badly contaminated uranium solutions may be determined quickly using visual comparison methods to an accuracy of [...]. This accuracy may be considerably improved by employing the fluorimeter herein described. Interfering ions and their removal using liquid-liquid extractions are considered."
Date: May 28, 1948
Creator: Grimes, W. R. & Clark, F. E.
Partner: UNT Libraries Government Documents Department

A Fluorimetric Study of the Thorium-Morin System

Description: The following report evaluates the fluorescent system of the reaction between morin and thorium in weakly acid solutions in order to form a stable yellow complex which fluoresces yellow-green when its solutions are irradiated with ultraviolet light. The system is evaluated as a basis for the quantitative determination of trace amounts of thorium, and some of the theoretical and mathematical relationships between fluorescence and light absorption are also included.
Date: April 1956
Creator: Milkey, Robert G. & Fletcher, Mary H.
Partner: UNT Libraries Government Documents Department

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

Microwave-Assisted Synthesis and Photophysical Properties of Poly-Imine Ambipolar Ligands and Their Rhenium(I) Carbonyl Complexes

Description: The phenomenon luminescence rigidochromism has been reported since the 1970s in tricarbonyldiimine complexes with a general formula [R(CO)3LX] using conventional unipolar diimine ligands such as 2,2;-bipyridine or 1,10-phenanthroline as L, and halogens or simple solvents as X. As a major part of this dissertation, microwave-assisted synthesis, purification, characterization and detailed photoluminescence studies of the complex fac-[ReCl(CO)3L], 1, where L = 4-[4,6-bis(3,5-dimethyl-1H-pyrazol-1-yl]-N,N-diethylbenzenamine are reported. The employment of microwaves in the preparation of 1 decreased the reaction time from 48 to 2 hours compared to the conventional reflux method. Stoichiometry variations allows for selective preparation of either a mononuclear, 1, or binuclear, fac-[Re2Cl2(CO)6], 2, complex. The photophysical properties of 1 were analyzed finding that it possesses significant luminescence rigidochromism. The steady state photoluminescence emission spectra of 1 in solution shift from 550 nm in frozen media to 610 nm when the matrix becomes fluid. Moreover, a very sensitive emission spectral analysis of 0.1 K temperatures steps shows a smooth transition through the glass transition temperature of the solvent host. Furthermore, synthetic modifications to L have attained a family of ambipolar compounds that have tunable photophysical, thermophysical and other material properties that render them promising candidates for potential applications in organic electronics and/or sensors - either as is or for their future complexes with various transition metals and lanthanides.
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Date: August 2017
Creator: Salazar Garza, Gustavo Adolfo
Partner: UNT Libraries