8 Matching Results

Search Results

Results: 1 - 8
open access

Evaluation of the {sup 4}I{sub 11/2} terminal level lifetime for several neodymium-doped laser crystals and glasses

Description: All models of lasing action require knowledge of the physical parameters involved, of which many can be measured or estimated. The value of the terminal level lifetime is an important parameter in modeling many high power laser systems since the terminal level lifetime can have a substantial impact on the extraction efficiency of the system. However, the values of the terminal level lifetimes for a number of important laser materials such as ND:YAG and ND:YLF are not well known. The terminal le… more
Date: April 25, 1995
Creator: Bibeau, C.
Partner: UNT Libraries Government Documents Department
open access

Development of radiation detectors based on hydrogenated amorphous silicon and its alloys

Description: Hydrogenated amorphous silicon and related materials have been applied to radiation detectors, utilizing their good radiation resistance and the feasibility of making deposits over a large area at low cost. Effects of deposition parameters on various material properties of a-Si:H have been studied to produce a material satisfying the requirements for specific detection application. Thick(-{approximately}50 {mu}m), device quality a-Si:H p-i-n diodes for direct detection of minimum ionizing parti… more
Date: April 1, 1995
Creator: Hong, Wan-Shick
Partner: UNT Libraries Government Documents Department
open access

Photofragment translational spectroscopy of three body dissociations and free radicals

Description: This dissertation describes several three-body dissociations and the photodissociation of methyl radicals studied using photofragment translational spectroscopy. The first chapter provides an introduction to three body dissociation, examines current experimental methodology, and includes a discussion on the treatment of photofragment translational spectroscopy data arising from three-body fragmentation. The ultraviolet photodissociation of azomethane into two methyl radicals and nitrogen is dis… more
Date: April 1, 1995
Creator: North, S.W.
Partner: UNT Libraries Government Documents Department
open access

Nonlinear optical spectroscopy of diamond surfaces

Description: Second harmonic generation (SHG) and infrared-visible sum frequency generation (SFG) spectroscopies have been shown to be powerful and versatile for studying surfaces with submonolayer sensitivity. They have been used in this work to study bare diamond surfaces and molecular adsorption on them. In particular, infrared-visible SFG as a surface vibrational spectroscopic technique has been employed to identify and monitor in-situ surface bonds and species on the diamond (111) surface. The CH stret… more
Date: April 1, 1995
Creator: Chin, R.P.
Partner: UNT Libraries Government Documents Department
open access

Dynamics of inelastic and reactive gas-surface collisions

Description: The dynamics of inelastic and reactive collisions in atomic beam-surface scattering are presented. The inelastic scattering of hyperthermal rare gaseous atoms from three alkali halide surfaces (LiF, NaCl, GI)was studied to understand mechanical energy transfer in unreactive systems. The dynamics of the chemical reaction in the scattering of H(D) atoms from the surfaces of LIF(001) and the basal plane of graphite were also studied.
Date: April 1, 1995
Creator: Smoliar, L.A.
Partner: UNT Libraries Government Documents Department
open access

Solution based temperature of Perovskite-type oxide films and powders

Description: Conventional solid state reactions are diffusion limited processes that require high temperatures and long reaction times to reach completion. In this work, several solution based methods were utilized to circumvent this diffusion limited reaction and achieve product formation at lower temperatures. The solution methods studied all have the common goal of trapping the homogeneity inherent in a solution and transferring this homogeneity to the solid state, thereby creating a solid atomic mixture… more
Date: April 1, 1995
Creator: McHale, J.M. Jr.
Partner: UNT Libraries Government Documents Department
open access

Quantum Monte Carlo for electronic structure: Recent developments and applications

Description: Quantum Monte Carlo (QMC) methods have been found to give excellent results when applied to chemical systems. The main goal of the present work is to use QMC to perform electronic structure calculations. In QMC, a Monte Carlo simulation is used to solve the Schroedinger equation, taking advantage of its analogy to a classical diffusion process with branching. In the present work the author focuses on how to extend the usefulness of QMC to more meaningful molecular systems. This study is aimed a… more
Date: April 1, 1995
Creator: Rodriguez, M.M.S.
Partner: UNT Libraries Government Documents Department
open access

Slag recycling of irradiated vanadium

Description: An experimental inductoslag apparatus to recycle irradiated vanadium was fabricated and tested. An experimental electroslag apparatus was also used to test possible slags. The testing was carried out with slag materials that were fabricated along with impurity bearing vanadium samples. Results obtained include computer simulated thermochemical calculations and experimentally determined removal efficiencies of the transmutation impurities. Analyses of the samples before and after testing were ca… more
Date: April 5, 1995
Creator: Gorman, P.K.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen