Thesis (M.S.)--University of Wisconsin--Madison, 1961. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 120-130).

Inaug.--diss.--Upsala. / "Literaturverzeichnis": p. 88.

Thesis--Catholic Univ. of America. / Includes bibliographical references.

Thesis (Ph. D.)--University of Hawaii at Manoa, 2001. / Includes bibliographical references (leaves 69-74). Also available by subscription via World Wide Web.

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A constant temperature room has been constructed in which the thermoregulator is controlled by a temperature-sensitive resistance. A thermostat has been constructed in which the 0 temperature is controlled to within 0.001°C. A precision conductance bridge has been built in a very convenient form. Improvements include the replacement of the telephone as null detector by a cathode ray oscilloscope, and the use of a resistance-capacity phase-shift oscillator, which gives a good wave-form. An automatic recycling conductance water still has been built which regularly gives water with a conductivity less than 0.09 micromhos per cm. The conductivities of dilute KCl solutions have been measured, taking special care to prevent errors due to the adsorption of KCl on the surface of glass. Two cells were used for these measurements : a modified Jones cell, and a special conductimetric titration cell. The modified Jones cell has given results in good agreement with the generally-accepted values. The results of the conductimetric titration cell do not agree well with the generally-accepted values; the greatest difference (for the most dilute solution) is 0.4%. The reason for this is not known.

The luminescent decay of pure potassium iodide has been measured under various conditions of temperature, annealing and x-irradiation time. The decay curves are found to be approximately of the form I(t) = [formula omitted] where I(t) is the luminescent intensity at the time t. Using a method that has been developed for the analysis of decay curves, numerical values for the decay constants, λi , and the trap populations Pi, have been estimated. The decay constants are found to be simple temperature functions of the form λi = [formula omitted] with the activation energies, Ei, lying between 0.4 and 0.8 ev and escape probabilities, Si, between 10⁴ and 10⁸ sec.⁻¹. The temperature dependence of the Pi is complicated and indicates that radiationless transitions strongly contribute to the emptying of traps at high temperatures. An irreversible increase in luminescent output produced by repeated x-irradiation without intermediate annealing is discovered; it points to considerable deviation from a first order decay mechanism in the case of slowly decaying traps. The mechanism of the irreversible effect is discussed on a semi-quantitative basis. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

Measurements and calculations of the far-infrared optical properties of K ³⁹I at 300, 77, and 12*K are presented. The measurements are mainly those of absorption in crystals of various thicknesses. The calculation assumed cubic anharmonicity only, with nearest-neighbour coupling, and the input lattice-dynamlcal data were obtained from a shell-model program. These data were generated with a wave vector density of 32000 points per zone, which, was sufficient to give 2-3 cm⁻¹ resolution. The over-all agreement between experiment and theory, in both: the intensity and structure of the spectra, is good. The magnitude of certain calculated features is, however, too large, indicating a need to consider next-nearest-neighbour interactions. Evidence was also found for three-phonon damping, both beyond the two-phonon limit at all temperatures and at J[sub o] by 300°K. From these measurements it was possible to calculate portions of the three-phonon damping spectra, which were found to be reasonable. The higher-phonon effects at 300°K did not seem to be noticeably more pronounced than those found in the much harder LiF, and arguments are presented to understand this. Finally, the isotope-induced one-phonon processes which occur in natural KI were calculated. These are shown to be small away from the resonance frequency v, and not to be the major damping mechanism at V[sub e] at low, temperatures^ in contrast to Lif. / Science, Faculty of / Physics and Astronomy, Department of / Graduate

Thesis (Ph. D.)--University of Virginia, 2001. / Includes bibliographical references (leaves 144-167). Also available online through Digital Dissertations.

published_or_final_version / Medical Sciences / Master / Master of Medical Sciences