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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.
71

Ion Chromatographic Determination of Haloacetates in Environmental Samples

Wang, F January 2004 (has links) (PDF)
A method is reported for the sensitive, simultaneous determination of mono-, di-, and trifluoroacetates by ion chromatography. These species were separated using a Dionex AS17 anion-exchange column employed with a potassium hydroxide gradient (via a Dionex EG40 Eluent Generator) and suppressed conductivity detection. The fluoroacetates were successfully separated from a range of inorganic and organic species likely to be present in environmental samples, in a total analysis time of 35 min (including re-equilibration of the column). Detection limits for mono-, di- and trifluoroacetate were 21, 38 and 36 micrograms/L, respectively, determined using a signal to noise ratio of 3, and were obtained using a sample injection volume of 50 microlitres. Precision was less than 0.83% relative standard deviation for replicate injections performed over a period of 30 days. The method was applied to the determination of MFA, DFA and TFA in river water, carrot baits, urine samples and different kinds of plant material including Bilobum, Calvcinum and Spinosum, and found the concentration range of mono-(MFA), di-(DFA), tri-fluoroacetate (TFA) to be 11-788, 3.5-17 and 0.22-1.2 ppm in wet weight plant samples respectively. Further research was carried out using the Dionex equipment specified above. A comparative study was made of the chromatographic behaviour of nine haloacetic acids mono-(MFA), di-(DFA), tri-fluoroacetate (TFA); mono-(MCA), di-(DCA), trichloroacetate (TCA) and mono-(MBA), di-(DBA), tri-bromoacetate (TBA). The techniques included anion-exchange chromatography with suppressed conductivity and UV detection. All nine haloacetic acids were completely separated under the optimised gradient elution conditions. Using selective detection methods or by pretreating samples with a OnGuard II Ag cartridge, eliminated some interference. The procedure for the simultaneous determination of the nine haloacetic acids was simple and fast. The method detection limits for MFA, DFA, TFA, MCA, DCA, TCA, MBA, DBA, and TBA were 21, 40, 40, 48, 28, 86, 67, 55, and 160 ppb respectively, determined using a signal to noise ratio of 3. Applications of these methods for the determination of haloacetic acids in real soil samples are shown.
72

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).
73

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).
74

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.
75

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.
76

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.
77

Image charge detection and image charge detection mass spectrometry

Zilch, Lloyd W. January 2008 (has links)
Thesis (Ph. D.)--Indiana University, Dept. of Chemistry, 2008. / Title from home page (viewed Oct. 8, 2009). Source: Dissertation Abstracts International, Volume: 70-02, Section: B, page: 0994. Adviser: Martin F. Jarrold.
78

Development of a hybrid tandem mass spectrometer for ultraviolet photodissociation of biomolecules

Kim, Tae-Young. January 2009 (has links)
Thesis (Ph.D.)--Indiana University, Dept. of Chemistry, 2009. / Title from PDF t.p. (viewed on Jul 22, 2010). Source: Dissertation Abstracts International, Volume: 70-12, Section: B, page: 7531. Adviser: James P. Reilly.
79

Uncovering the biosynthesis of natural products using Fourier-Transform mass spectrometry /

Thomas, Paul Martin, January 2009 (has links)
Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2009. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3482. Adviser: Neil L. Kelleher. Includes bibliographical references. Available on microfilm from Pro Quest Information and Learning.
80

Separation of combinatorial library isomers using ion mobility/mass spectrometry techniques

Hilderbrand, Amy E. Unknown Date (has links)
Thesis (Ph. D.)--Indiana University, Dept. of Chemistry, 2005. / Source: Dissertation Abstracts International, Volume: 66-12, Section: B, page: 6578. Adviser: David E. Clemmer. Title from dissertation home page (viewed Oct. 11, 2006).

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