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Properties of Molecular Rydberg States

Description: Many of the bands in the vapor-phase far-ultraviolet absorption spectra of simple molecules can often be fit to mathematical progressions referred to as molecular Rydberg series. The name Rydberg arises from the similarity between the Rydberg formula for the atomic hydrogen spectrum and the formulae for the progressions found in molecular spectra. The theories of molecular Rydberg transitions and states are discussed in terms of the inferences that have been made in the past from the available … more
Date: December 1974
Creator: Scott, John Delmoth
Partner: UNT Libraries
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Organelle- and Organ-Specific Isozymes of Euglena Gracilis and Catfish

Description: Two distinct compartmentalized isozymes of aldolase and triosephosphate isomerase were examined in the photoautotrophically and heterotrophically grown green alga Euglena gracilis. A comparison of the chemical and physical properties of the isozymes was carried out. Isozymes of phosphoglucose isomerase were isolated in homogeneous form from liver and muscle tissue of the fresh water catfish. The two organ-specific isozymes were essentially identical with respect to their molecular weights but e… more
Date: December 1974
Creator: Mo, Yeh-Chun
Partner: UNT Libraries
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The Vacuum Ultraviolet Spectra of Cyclohexane, Cyclohexene, 1,4-Cyclohexadiene, Isotetralin, and Several Methyl Substituted Analogs

Description: A paucity of literature exists on the Independent System analysis of adjacent, parallel transition dipoles. Applying this theory and certain spectral information semiemperical calculations were made to predict absorption profiles and band intensities. To aid in the assignment of the 7*+7 absorption bands it was necessary to obtain the vacuum ultraviolet spectra of cyclohexane and cyclohexene. Because the spectra of these molecules contained sharp, atomic-like absorption bands a Rydberg series c… more
Date: December 1974
Creator: Tidwell, Edgar Rhea
Partner: UNT Libraries
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Inhibitors of Dihydrofolate Reductase, 8-Oxapteridines

Description: The biological activities of some homeosterically related analogs of dihydrofolic acid have been examined involving pyrimido[4,5-b][l,4]oxazine (8-oxapteridine) derivatives. It is anticipated that these compounds might interfere with the essential intermediary metabolic functions of the vitamin and thus serve as potential chemotherapeutic agents. Preliminary toxicity studies in microbial assay systems were disappointing; however, inhibitory effects were demonstrated in cell free enzyme systems… more
Date: December 1974
Creator: Lin, Shwu-Ching H.
Partner: UNT Libraries
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Long-Range Carbon-13--Carbon-13 Spin-Spin Coupling Constants

Description: The study consists of three major areas of research. First, the dihedral angle dependence of vicinal carbon-carbon coupling constants is determined for aliphatic and alicyclic carboxylic acids wherein the formal hybridization and substituents are held constant. Second, the magnitudes and relative signs of long-range carbon-carbon coupling constants in a. triple- 13 C-labeled system are determined and compared with carbon-proton and/or proton-proton coupling constants in geometrically similar co… more
Date: December 1974
Creator: Miller, Denis E.
Partner: UNT Libraries
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Structure-Activity Studies of Halopyrethroids

Description: The structures of the new pyrethroids were elucidated utilizing nuclear magnetic spectroscopy and elemental analysis. The biological activity of the pyrethroids has been evaluated for houseflies and yellow fever mosquitoes. A correlation of increase in rapid knockdown and toxicity with decrease in size of halogen has been made. The most effective compound, the difluorovinyl ester, has a toxicity of 123 times greater than pyrethrins. This degree of toxicity has not previously been reported for a… more
Date: December 1974
Creator: Brown, Dale Gordon
Partner: UNT Libraries
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