Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Thesis (Ph.D.)--Drexel University, 2009. / Includes abstract and vita. Includes bibliographical references (leaves 204).

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002. / Includes bibliographical references. Also available in electronic version. Access restricted to campus users.

Thesis (Ph. D.)--Brigham Young University. Dept. of Chemistry and Biochemistry, 2004. / Includes bibliographical references.

Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.

A high resolution speedy delivery time domain reflectometer (SD/TDR) has been developed in the Electrical Engineering department at The University of Texas at Austin. The SD/TDR uses a novel non-sinusoidal signal that does not undergo dispersion during transmission in a lossy media. SD/TDR is used to estimate the length and detect the location of faults in the transmission lines. Time of flight (TOF) is one of the critical parameters of SD/TDR and a function of several temperature dependent factors. Given the TOF and length of a transmission line, signal delay can be computed. This research presents an empirical study of the effect of temperature on the TOF in a plenum grade coaxial cable for temperatures ranging from -3 °C to 60 °C. We also study the effect of temperature on characteristic impedance of the coaxial cable. Finally, a SD double exponential waveform is used to estimate TOF for calibrated short and open terminations. / text

Polyyne molecules were produced as a result of the femtosecond laser irradiation of liquid acetone (CH3)2CO and alkane molecules hexane C6H14 and octane C8H18 using 800 nm, 100 fs duration pulses. These polyynes have been detected as a Raman band in irradiated liquid from 1800 to 2200 cm−1. Polyyne molecules generally detected as a Raman band in SERS experiment are C8H2, C10H2, C12H2 and C14H2. Two well established experimental techniques, time of flight mass spectrometry and surface enhanced Raman spectrometry were used to identify positively polyyne formation as a result of femtosecond laser irradiation of acetone and alkane liquids. Small polyynes C2H2, C4H2, and C6H2 were positively detected in the time of flight mass spectrometer TFMS, while longer polyynes from C6H2, C8H2, C10H2, C12H2 and C14H2 were detected by surface enhanced Raman spectroscopy SERS. Intensity capping occurs in a liquid due to filamentation, and the resulting intensity in a liquid is s 1013 W/cm2 during irradiation. This results in main process of ionization in the larger part of the laser focus as multiphoton ionization MPI. Focal volume increase in a liquid provides a larger volume where ions C+, C+2 and C2+are produced to initiate chemical reactions outside the laser focus. The current work established positively, that the longer polyyne formation does not occur by dehydrogenation of alkane molecules by only breaking the C-H bonds as was previously anticipated. It is proposed in this work that lengthening of polyyne chains occurs due to addition reaction of species of C+, C+2 and C2+ to double bonded species themselves produced as a result of the breaking down of the parent molecules in the laser focus. The carbon addition reactions occur outside the laser focus due to the close proximity of molecules in the liquid phase.

No description available.