Thesis (Ph. D.)--Florida State University, 2006. / Advisor: Richard Bertram, Florida State University, College of Arts and Sciences, Program in Molecular Biophysics. Title and description from dissertation home page (Sept 18, 2006). Document formatted into pages; contains xii, 225 pages. Includes bibliographical references.

Thesis (Ph.D.)--University of Delaware, 2007. / Principal faculty advisor: Tatyana Polenova, Dept. of Chemistry & Biochemistry. Includes bibliographical references.

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 218-233).

Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 197-209).

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2008. / Title from title screen (site viewed Feb. 17, 2009). PDF text: 182 p. : ill. (chiefly col.) ; 5 Mb. UMI publication number: AAT 3328255. Includes bibliographical references. Also available in microfilm and microfiche formats.

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A systematic and efficient route to [e]-annelated derivatives of 2,7-di-t- butyl-trans-10b, 10c-dimethyl-10b,10c-dihydropyrene 34 has been achieved which provides access to the benzo, naphtho, and anthro derivatives of 34, by means of a Diels - Alder reaction of an aryne with a furan. Reaction of the annulyne derived from bromide 50 with furan gave adduct 52 which could be both deoxygenated to benzo derivative 53 and reacted with tetrazine 54 to yield the annuleno furan 55 which subsequently with benzyne and 2,3-naphthalyne yielded adducts which were deoxygenated to naphtho and anthro derivatives 57 and 59. Reaction of the furan 55 with the benzoannulyne derived from 65 gave the cyclophane fused pyrene 68, while reaction of the annulyne derived from 50 with the bisfuran 62 gave the chrysene bis pyrene 60. These fused dihydropyrene derivatives are all photochromic, and the photoisomerizations were studied In each case. Dihydropyrenes 53, 57, 59, and 65 are simple photoswitches, while 60 and 68 are more complex multiple state switches. In each case the kinetics of the MOD to DMDHP reaction was followed to obtain the activation energy, enthalpy, and entropy. It was found that the activation enthalpies and energies decreased through the series, from the benzo to the naphtho to the anthro system. This suggested that the transition states for the MCD to DMDHP reactions were stabilized by resonance with the respective annelated fragments. Detailed analysis of the NMR data of all compounds yielded an experimental aromaticity scale in which δ(Me) or δ(H4) could yield information to obtain the relative resonance energy of the annelating fragment. Correlations between methyl and H4 protons were obtained and compared to related systems. / Graduate

The diffusion of small molecules into glassy polymers is often observed to be of the anomalous Case II type. This thesis describes the first comprehensive study of acetone vapour penetrating into PVC. It has been shown that this diffusion process is of the Case II type. The initial stages of the diffusion process have been studied using ion beam nuclear reaction analysis (NRA) whilst long range diffusion has been studied using broadline nuclear magnetic resonance (NMR) imaging techniques. This is the first time that short and long term behaviour has been studied in the same system and has permitted a test of the Thomas and Windle theory covering both regimes. It is also the first time that broadline NMR imaging has been used to study Case II diffusion and this has permitted a study of the polymer as well as the penetrant. A new NMR technique has been developed for this. Characteristic parameters of the diffusion process have been determined. The velocity of the diffusion front advance is typically 0.042 mmhr-1 and the diffusion coefficient is 7 x10-11 cm2s-1 at room temperature. The effects of variation of exposure temperature and the activity of the vapour on the diffusion dynamics have been investigated. The NMR profiles have shown an unexpectedly long Fickian precursor extending into the inner glassy core of the samples. To complement the NMR imaging results, the NMR spin spin relaxation times of samples have been measured, and high resolution 13C NMR spectroscopy has been performed on the samples. Evidence has been found for continued disentanglement of the polymer chains long after mass equilibration of the region of the PVC swollen by acetone vapour. This disentanglement has been shown to be strongly dependent on the exposure temperature.

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