Thesis (Ph.D.)--University of Nebraska-Lincoln, 2006. / Title from title screen (site viewed on Feb 8, 2007). PDF text: 258 p. : ill. (some col.). UMI publication number: AAT 3218192. Includes bibliographical references. Also available in microfilm and microfiche format.

Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (leaves 186-192).

No description available.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2007. / Title from title screen (site viewed Dec. 4, 2007). PDF text: x, 362 p. : ill. ; 13 Mb. UMI publication number: AAT 3271933 . Includes bibliographical references. Also available in microfilm and microfiche formats.

Thesis (Ph.D.) -- McMaster University, 1998. / Includes bibliographical references. Also available via World Wide Web.

Controlled free radical polymerization facilitates the production of polymers with highly defined microstructures like traditional ionic polymerization; but in contrast allows for previously unattainable monomer combinations such as acrylic acid in its non-protected form. Incorporation of acrylic acid into styrene was done by random copolymerization of acrylic acid (directly and in its protected form as tert-butyl acrylate) with styrene. Styrene/tert-butyl acrylate (S/t-BuA) as well as styrene/acrylic acid (S/AA) mixtures were copolymerized to form tapered or gradient copolymers. Using an alkoxyamine unimolecular initiator, 2-[N- tert-butyl-2,2-(dimethylpropyl)aminooxy] propionic acid (BlocBuilder RTM), along with additional free nitroxide (SG1), the effect of acid protection on polymerization kinetics and copolymer composition was determined. Adding 4.5 mol% SG1/BlocBuilderRTM greatly improved the control of S/t-BuA copolymerization with low polydispersities (1.14-1.22) whereas the S/AA required higher levels of SG1 to produce polymers with low polydispersities that were comparatively still broader compared to the S/t-BuA system (polydispersities ∼ 1.3-1.4 at 9 mol% SG1/BlocBuilderRTM). S/AA copolymerization required higher SG1 concentrations to compensate for degradation of SG1 by attack from the acrylic acid monomer.

Thesis (M.S.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains ix, 80 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 51-52).

Thesis (M.S.)--Florida State University, 2005. / Advisor: Timothy Logan, Florida State University, College of Arts and Sciences, Dept. of Chemistry and Biochemistry. Title and description from dissertation home page (viewed Feb. 1, 2006). Document formatted into pages; contains viii, 37 pages. Includes bibliographical references.

No description available.

Two-photon absorption and upconverted fluorescence has been utilized in a variety of applications in pure science and engineering. Multiphoton-based techniques were used in this research in order to understand photophysical and chemical characteristics of several fluorescent dyes and to demonstrate some of their key applications. Two-photon fluorescence microscopy (2PFM) has become a powerful technique in bio-photonics for non-invasive imaging in the near-infrared (NIR) region (700~1000 nm) that often results in less photobleaching. In Chapter 1, there is a brief introduction to fluorescence, examples of fluorescence materials, and a discussion of the advantages of two-photon absorption. 2PFM imaging was utilized in Chapters 2 to 4 for various applications. In Chapter 2, a new squaraine dye is introduced and its linear and nonlinear photophysical properties are characterized. This compound has very high two-photon absorption (2PA) cross sections and high photostability both in an organic solvent and when encapsulated in micelles. Based on these properties, this dye was demonstrated as a near-infrared (NIR) probe in in vitro 2PFM imaging with excitation over 800 nm wavelength. In Chapter 3, new profluorescent nitroxides are introduced. Nitroxide radicals are utilized for electron paramagnetic resonance (EPR) spectroscopy and in biological systems as some are known, in some manner, to mimic the behavior of superoxide dismutase (SOD) that detoxifies or mitigates oxidative stress by trapping free radicals. Here, two profluorescent nitroxides investigated for use as a two-photon fluorescent oxidative stress indicator in in vitro two-photon fluorescence microscopy (2PFM) imaging. In Chapter 4, two-photon excited (2PE) fluorescence of a conjugated polyelectrolyte (CPE), PPESO3, was studied in methanol and in water. The results of CPE quenching studies were comparable under both one-photon excitation conditions and two-photon excitation. CPE coated silica nanoparticles were incubated in HeLa cells and 2PFM imaging was demonstrated for this new class of fluorescent probe. Supramolecular structures based on organized assemblies/aggregation of chromophores have attracted widespread interest as molecular devices with potential applications in molecular electronics, artificial light harvesting, and pharmacology. In Chapter 5, J-aggregate formation was investigated for two porphyrin-based dyes, 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS, 4) and an amino tris-sulfonate analog (5) in water via UV-vis, fluorescence, and lifetime decay studies. The effect of aggregation on two-photon absorption properties was also investigated. A functionalized norbornene-based homopolymer, synthesized by the ring opening metathesis polymerization technique was used as a J-aggregation enhancement template and had a role of polymer-templating to facilitate porphyrin aggregation and modulate 2PA. In Chapter 6, squaraine dye aggregates templated with single wall carbon nanotubes (SWCNTs) that were atomically clean were studied by using optical absorption spectroscopy, atomic force microscopy (AFM), and photoconductivity measurements. SWCNTs selectively promote the formation of squaraine dye aggregates with a head-to-head stacking arrangement, and these dye aggregates effectively photosensitize SWCNTs, demonstrating that this novel approach can yield highly photosensitized devices.