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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
321

Aryl halides and metabolites : new approaches to quantitation

Paleologou, Michael January 1990 (has links)
A novel reaction for the dehalogenation of aryl halides is discussed in terms of its stoichiometry, mechanism, yields and potential for analytical purposes. The active dehalogenation reagent can be prepared through the reaction of molten potassium with polyethylene glycols (MW $>$ 200), in the absence of oxygen, to form the corresponding potassium glycolate, a powerful nucleophilic agent. This reaction is applied to the determination of PCBs in waste oils. Following dechlorination, the reaction sample is analyzed for chloride using a flow-injection analysis system employing a novel thin-layer amperometric detector with a silver working electrode. / The liquid chromatographic retention behaviour, separation and detection (UV and electrochemical) of nineteen monoaromatic chlorophenols was investigated on a $ beta$-cyclo-dextrin bonded-phase column with respect to mobile phase composition, pH, temperature and ionic strength; this behaviour was compared with other reversed phase columns. The same methodology was also applied to the study of the retention behaviour and gradient elution separation of fourteen diaromatic chlorophenols (PCB metabolic analogues).
322

The separation of lipoproteins and the determination of cholesterol in human serum /

Carpenter, Alexis Anne January 1991 (has links)
A flow-injection system is described which employs immobilized cholesterol esterase and cholesterol oxidase for the determination of total serum cholesterol. Hydrogen peroxide generated by the enzymatic reaction is measured directly at a home-made amperometric thin-layer flow-cell held at +600 mV vs Ag/AgCl. Serum samples are passed through an anion exchange resin to remove possible interferences prior to detection. The accuracy and precision of the system were evaluated with the use of certified reference materials for serum cholesterol and were found to conform to the recommended guidelines of the Laboratory Standardization Panel at the National Institutes of Health. / The use of sulfated polysaccharides as an affinity medium for the separation of the major classes of lipoproteins with subsequent determination of their cholesterol content was investigated. Several immobilization procedures for the covalent attachment of heparin to controlled-pore glass (CPG) were attempted. Separation of $ alpha$- (high-density) and $ beta$- (low- and very-low-density) lipoproteins was achieved on one of the heparin-CPG preparations and incorporation of this material into a chromatographic system with on-line determination of cholesterol was investigated. / Separation of $ alpha$- and $ beta$-lipoproteins was also achieved using sulfated dextran beads. A simple two-step procedure separates these two fractions in 10 minutes, and the cholesterol content is determined using the flow-injection system described above.
323

Vibrational spectroscopic studies of orientationally-disordered organic cage molecules

Kawai, Nancy T. January 1991 (has links)
The phase behaviour of six orientationally-disordered organic cage molecules, norbornane, norbornylene, norbornadiene, quadricyclane, bicyclooctene, and fluoroadamantane, has been characterized by differential scanning calorimetry, and variable-temperature and -pressure infrared and Raman spectroscopy. All of these compounds undergo one or more solid-solid phase transitions on cooling from disordered phases to ordered, crystalline structures, except for fluoroadamantane, which forms a glass. The phases of all these solids under high pressure have been shown to be the same as those formed at low temperatures. / A method of using pressure dependences of vibrational modes to aid in making spectral assignments is proposed, which proved to be very useful in classifying C-H stretching vibrations and modes which have large contributions from skeletal stretching motions. A semiquantitative analysis of the effect of pressure on different types of stretching vibrations is described.
324

Biochemical applications of microcolumn separation techniques

Starkey, Jason A. January 2007 (has links)
Thesis (Ph. D.)--Indiana University, Dept. of Chemistry, 2007. / Source: Dissertation Abstracts International, Volume: 68-09, Section: B, page: 5919. Adviser: Milos V. Novotny. Title from dissertation home page (viewed May 9, 2008).
325

Proteome measurements for developing hypotheses about the biology of Drosophila

Sowell, Rena A. January 2007 (has links)
Thesis (Ph. D.)--Indiana University, Dept. of Chemistry, 2007. / Source: Dissertation Abstracts International, Volume: 68-09, Section: B, page: 5918. Adviser: David E. Clemmer. Title from dissertation home page (viewed May 12, 2008).
326

Investigation of toxic organic chemicals in the environment

Venier, Marta. January 2008 (has links)
Thesis (Ph. D.)--Indiana University, School of Public and Environmental Science Affairs, 2008. / Title from PDF t.p. (viewed May 13, 2009). Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4637. Adviser: Ronald A. Hites.
327

Applications of 157 nm light photofragmentation for the structural characterization of isomeric glycans and lipids

Devakumar, ArugaDoss. January 2008 (has links)
Thesis (Ph. D.)--Indiana University, Dept. of Chemistry, 2008. / Title from PDF t.p. (viewed May 13, 2009). Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4721. Adviser: James P. Reilly.
328

Sampling, detection, and characterization of endogenous peptides /

Richmond, Timothy Alan. January 2007 (has links)
Thesis (Ph. D.)--University of Illinois at Urbana-Champaign, 2007. / Source: Dissertation Abstracts International, Volume: 68-07, Section: B, page: 4441. Adviser: Jonathan V. Sweedler. Includes bibliographical references. Available on microfilm from Pro Quest Information and Learning.
329

Profiling and imaging the nervous system with mass spectrometry /

Monroe, Eric Britain. January 2008 (has links)
Thesis (Ph. D.)--University of Illinois at Urbana-Champaign, 2008. / Source: Dissertation Abstracts International, Volume: 69-05, Section: B, page: 2965. Adviser: Jonathan v. Sweedler. Includes bibliographical references. Available on microfilm from Pro Quest Information and Learning.
330

Solid-state nuclear magnetic resonance spectroscopy of alpha-synuclein fibrils /

Kloepper, Kathryn D. January 2008 (has links)
Thesis (Ph. D.)--University of Illinois at Urbana-Champaign, 2008. / Source: Dissertation Abstracts International, Volume: 69-11, Section: B, page: 6759. Adviser: Chad M. Rienstra. Includes bibliographical references. Available on microfilm from Pro Quest Information and Learning.

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