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dc.contributor.authorStevenson, Steven A.en
dc.date.accessioned2014-03-14T21:46:12Zen
dc.date.available2014-03-14T21:46:12Zen
dc.date.issued1992-06-05en
dc.identifier.otheretd-09192009-040407en
dc.identifier.urihttp://hdl.handle.net/10919/44860en
dc.description.abstractThe primary difficulty for successful LC - ¹³C NMR (whether ¹H or ¹³C) is overcoming the relatively low sensitivity of NHR as a chromatographic detector. For the ¹H nuclide this is much less of a problem; the sensitivity ;s approximately 6000 times more sensitive than that of ¹³C nuclei. For this reason, much of the literature focuses on LC - ¹H NMR. To ever successfully realize LC - ¹³C NMR, it is mandatory that an augmentation of ¹³C signal intensity must be effectuated to overcome this sensitivity deficit (~ three orders of magnitude). To satisfy this requirement, our laboratory has utilized dynamic nuclear polarization (DNP) to ameliorate these otherwise weak or non-existent signals. For favorable molecules, sensitivity recoveries of up to two orders of magnitude have been developed. This improvement (relative to 'H) narrows the sensitivity gap between 'H and ¹³C NMR detection of chromatographically separated analytes. Despite the fact that relatively large injection volumes were required in most LC experiments, the wealth of structural information inherent to ¹³C NMR justifies any attempt to successfully couple nuclear magnetic resonance to liquid chromatography. In addition, DNP was utilized in a series of SLIT and LLIT experiments where a test mixture was recycled through a NMR spectrometer. Results indicate that ¹³C spectra were obtained with a significantly higher signal-to-noise ratio in a shorter amount of analysis time relative to experiments where DNP was not employed for signal enhancement.en
dc.format.extentxv, 147 leavesen
dc.format.mediumBTDen
dc.format.mimetypeapplication/pdfen
dc.language.isoenen
dc.publisherVirginia Techen
dc.relation.isformatofOCLC# 27690884en
dc.relation.haspartLD5655.V855_1992.S748.pdfen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subject.lccLD5655.V855 1992.S748en
dc.subject.lcshLiquid chromatographyen
dc.subject.lcshNuclear magnetic resonanceen
dc.subject.lcshPolarization (Nuclear physics)en
dc.titleLC - ¹³C NMR utilizing dynamic nuclear polarization (DNP) for signal enhancementen
dc.typeThesisen
dc.contributor.departmentAnalytical Chemistryen
dc.description.degreeMaster of Scienceen
thesis.degree.nameMaster of Scienceen
thesis.degree.levelmastersen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.disciplineAnalytical Chemistryen
dc.contributor.committeechairDorn, Harry C.en
dc.contributor.committeememberAnderson, Mark R.en
dc.contributor.committeememberTaylor, Larry T.en
dc.type.dcmitypeTexten
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-09192009-040407/en
dc.date.sdate2009-09-19en
dc.date.rdate2009-09-19en
dc.date.adate2009-09-19en


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