366 Matching Results

Search Results

Results: 1 - 24 next
open access

Synthesis of organosilicon compounds

Description: Silicon-containing polymers have been a focus of synthesis and study in Dr. Barton`s group because of their chemistry and properties which are not offered by other systems or materials. For example, the polymer -[-SiMe{sub 2}C{triple_bond}C-]{sub n}-can be easily processed to films or fibers from melt or solution, and thermally converted to a SiC-containing ceramic in high yield at high temperature. In recent years, carbosilane dendritic polymers have been of great interests in many research gr… more
Date: December 31, 1996
Creator: Zhao, G.
Partner: UNT Libraries Government Documents Department
open access

The Utilization of Folk Song Elements in Selected Works by Ralph Vaughan Williams and Percy Grainger with Subsequent Treatment Exemplified in the Wind Band music of David Stanhope

Description: An examination of the utilization of folk song elements in the wind band music of Australian composer David Stanhope, represented in two movements ("Lovely Joan" and "Rufford Park Poachers") from his Folk Songs for Band. Sets 1 and 2. Included is an historical overview of English folk music, emphasizing the theoretical properties of the English folk song and the events surrounding the modern renaissance of British folk music. Background information related to the musical development of Vaughan … more
Date: May 1996
Creator: Birdwell, John Cody
Partner: UNT Libraries
open access

Photodissociation of ketene: CH{sub 2}CO {yields} CH{sub 2}(a{sup 1}A{sub 1}) + CO(v=1) rates and dynamics

Description: The rotational energy release in the dissociation of ketene (CH{sub 2}CO) along its singlet potential energy surface is observed and compared with several statistical and dynamical theories. Rotational distributions for the product, CO(X{sup 1}{Sigma}+)(v=1), are measured from the threshold for production of CH{sub 2}(a {sup 1}A{sub 1}) (0,0,0) + CO(X{sup 1}{Sigma}+)(v=1) to 1720 cm{sup -1} above. Near threshold (E{le} 200 cm{sup -1} over threshold), phase space theory (PST) matches the observe… more
Date: December 1, 1996
Creator: Wade, E.A.
Partner: UNT Libraries Government Documents Department
open access

The Waste Package Project. Final report, July 1, 1995--February 27, 1996: Volume 1, The structural performance of the shell and fuel rods of a high level nuclear waste container

Description: This dissertation proposal covers research work that started in the spring of 1992. The aim of the research has been to study the structural performance and stability of proposed nuclear waste containers and the enclosed fuel rods to be used in the long term storage of High Level Nuclear Waste (HLNW). This research is in two phases, computational and experimental. The computational phase deals with the linear and nonlinear Finite Element Analysis of the different containers due to various loadi… more
Date: June 1, 1996
Creator: Ladkany, S.G. & Rajagopalan, R.
Partner: UNT Libraries Government Documents Department
open access

Part 1. Investigation of Aluminum Amino Acid Complexes; Part 2. Structural Studies of Aluminum Chalcogen Bonds

Description: Five different complexes of aluminum and amino acids have been synthesized and characterized. Reaction between aluminum halides and amino acids that do not contain either a carboxylate or a hydroxy group in the side chain produce complexes of the general formula, [Al(amino acid)_n(halide)_3-n]_m. The most prevalent form of this form of complex is where n = 2, and an example of this in which the halide is replaced by hydroxide ligand has been structurally characterized. The complex for which n =… more
Date: May 1996
Creator: Gravelle, Philip W. (Philip Wyn)
Partner: UNT Libraries
open access

Measurement of the Angular Distribution of the Electron From W {r_arrow} E = {Nu} decay, in P{Anti P} at {Radical}S = 1.8 Tev, as Function of P{Sub T}{Sup W}; Medida De La Distribucion Angular Del Electron De W en E + Neutrino en P{Anti P} a 1.8 Tev

Description: The goal of this work was to study the behavior of the angular distribution of the electron form the decay of the W boson in a specific rest-frame of the W, the Collins-Soper frame. This thesis consists of four major divisions, each dealing with closely related themes: (a) Physics Background, (b) Description of the Hardware and General Software Tools, (c) Description of the Analysis and Specific Tools, and (d) Results and Conclusions. Each division is comprised of one or more chapters and each … more
Date: October 7, 1996
Creator: Ramos, M. I. M.
Partner: UNT Libraries Government Documents Department
open access

Determination of the feasibility of using open path FTIR to monitor levels of 3-methylfuran and 1-octen-3-ol for the purpose of detecting microbial contamination in indoor environments

Description: Studies have shown that the presence of microbial growth correlates with health complaints associated with sick building syndrome. Microbial growth may be found in damp places within a building, and may be dispersed to other areas if present in the HVAC system. Certain individuals may be especially sensitive to the presence of these microorganisms, and may experience adverse reactions at extremely low concentrations. Unfortunately, the source of the problem may not be discovered because many ti… more
Date: March 1, 1996
Creator: Olive, B.
Partner: UNT Libraries Government Documents Department
open access

[The Waste Package Project. Final report, July 1, 1995--February 27, 1996]: Volume 2, Experimental verification of structural response of a flexible three-link hydraulic steel robot

Description: This report presents experimental techniques for determining the static and dynamic response, in three dimensional space, of a flexible three-link hydraulic steel robot. The flexible robot was originally built under a grant from the Army Research Office (ARO) and has been the subject of a six year research project involving 12 graduate students and four faculty members. The research was continued under grant from the U.S. Department of Energy which is considering the use of robot in remote hand… more
Date: June 1, 1996
Creator: Ladkany, S.G. & Channarayapatna, S.S.
Partner: UNT Libraries Government Documents Department
open access

[The Waste Package Project. Final report, July 1, 1995--February 27, 1996]: Volume 3, Stress study in faulted tunnel models by combined photoelastic measurements and finite element analysis

Description: The aim of this part of the Nuclear Waste Package Project research at UNLV is to investigate the stresses in a model of a faulted mountain and the effect of the fault on the stability of drifts in a proposed High Level Nuclear Waste Repository. An investigation was performed to develop a proper technique for analyzing the stresses in and around three adjacent scaled tunnel models, along with the stress concentration factors resulting from the existence of a fault that penetrates two of the thre… more
Date: June 1, 1996
Creator: Ladkany, S. G. & Huang, Yuping
Partner: UNT Libraries Government Documents Department
open access

Decomposition of chlorinated ethylenes and ethanes in an electron beam generated plasma reactor

Description: An electron beam generated plasma reactor (EBGPR) is used to determine the plasma chemistry kinetics, energetics and decomposition pathways of six chlorinated ethylenes and ethanes: 1,1,1-trichloroethane, 1,1-dichloroethane, ethyl chloride, trichloroethylene, 1,1-dichloroethylene, and vinyl chloride. A traditional chemical kinetic and chemical engineering analysis of the data from the EBGPR is performed, and the following hypothesis was verified: The specific energy required for chlorinated VOC… more
Date: February 1, 1996
Creator: Vitale, S.A.
Partner: UNT Libraries Government Documents Department
open access

Structural and dynamic characterization of eukaryotic gene regulatory protein domains in solution

Description: Solution NMR was primarily used to characterize structure and dynamics in two different eukaryotic protein systems: the {delta}-Al-{var_epsilon} activation domain from c-jun and the Drosophila RNA-binding protein Sex-lethal. The second system is the Drosophila Sex-lethal (Sxl) protein, an RNA-binding protein which is the ``master switch`` in sex determination. Sxl contains two adjacent RNA-binding domains (RBDs) of the RNP consensus-type. The NMR spectrum of the second RBD (Sxl-RBD2) was assign… more
Date: May 1, 1996
Creator: Lee, A.L.
Partner: UNT Libraries Government Documents Department
open access

Kinetic Studies of the Reactions of Alkyl and Silyl Hydrides

Description: The Kinetics of the reactions involving alkyl and silyl hydrides were studied by the flash photolysis / resonance fluorescence technique. The reactions of alkyl radicals (R = C₂H₅, i-C₃H₇, t-C₄H₉) with HBr have been studied at room temperature and the rate constants obtained (units are in cm³ s^-1 ) are: k₃.₃ = (7.01 ± 0.15) x 10^-12, k₃.₂ = (1.25 ± 0.06) x 10^-11, k₃.₁ = (2.67 ± 0.13) x 10^-11 These results, combined with previously determined reverse rate constants and other kinetic informati… more
Date: August 1996
Creator: Yuan, Jessie (Jessie Win-Jae)
Partner: UNT Libraries
open access

The Effect of Psychometric Parallelism among Predictors on the Efficiency of Equal Weights and Least Squares Weights in Multiple Regression

Description: There are several conditions for applying equal weights as an alternative to least squares weights. Psychometric parallelism, one of the conditions, has been suggested as a necessary and sufficient condition for equal-weights aggregation. The purpose of this study is to investigate the effect of psychometric parallelism among predictors on the efficiency of equal weights and least squares weights. Target correlation matrices with 10,000 cases were simulated so that the matrices had varying degr… more
Date: May 1996
Creator: Zhang, Desheng
Partner: UNT Libraries
open access

A Simplified Spherical Harmonic Method for Coupled Electron-Photon Transport Calculations

Description: In this thesis we have developed a simplified spherical harmonic method (SP{sub N} method) and associated efficient solution techniques for 2-D multigroup electron-photon transport calculations. The SP{sub N} method has never before been applied to charged-particle transport. We have performed a first time Fourier analysis of the source iteration scheme and the P{sub 1} diffusion synthetic acceleration (DSA) scheme applied to the 2-D SP{sub N} equations. Our theoretical analyses indicate that t… more
Date: December 1, 1996
Creator: Josef, John A.
Partner: UNT Libraries Government Documents Department
open access

Generalized Function Solutions to Nonlinear Wave Equations with Distribution Initial Data

Description: In this study, we consider the generalized function solutions to nonlinear wave equation with distribution initial data. J. F. Colombeau shows that the initial value problem u_tt - Δu = F(u); m(x,0) = U_0; u_t (x,0) = i_1 where the initial data u_0 and u_1 are generalized functions, has a unique generalized function solution u. Here we take a specific F and specific distributions u_0, u_1 then inspect the generalized function representatives for the initial value problem solution to see if the … more
Date: August 1996
Creator: Kim, Jongchul
Partner: UNT Libraries
open access

Rare earth chalcogenides for use as high temperature thermoelectric materials

Description: In the first part of the thesis, the electric resistivity, Seebeck coefficient, and Hall effect were measured in X{sub y}(Y{sub 2}S{sub 3}){sub 1-y} (X = Cu, B, or Al), for y = 0.05 (Cu, B) or 0.025-0.075 for Al, in order to determine their potential as high- temperature (HT)(300-1000 C) thermoelectrics. Results indicate that Cu, B, Al- doped Y{sub 2}S{sub 3} are not useful as HT thermoelectrics. In the second part, phase stability of {gamma}-cubic LaSe{sub 1.47-1.48} and NdSe{sub 1.47} was mea… more
Date: January 2, 1996
Creator: Michiels, J.
Partner: UNT Libraries Government Documents Department
open access

Assessing Maternal Functioning in Families of Children with Autism

Description: Mothers and siblings of children with autism incur stressors that impact their well-being more adversely than mothers of children with ADHD or normally developing children. In Study 1, twenty-six mothers of children with autism (Group 1) were compared to 24 mothers of children with ADHD (Group 2) and 24 mothers with normally developing children (Group 3). All families included a normally developing child (ages 4 to 12). Measures to delineate levels of maternal functioning were administered. Re… more
Date: August 1996
Creator: Oizumi, Joelle J. (Joelle Julienne)
Partner: UNT Libraries
open access

The photosynthetic acclimation of Lolium perenne in response to three years growth in a free-air CO{sub 2} enrichment (FACE) system

Description: Pure stands of Ryegrass were in their third year of growth in the field, exposed to either ambient (355 {mu}mol mol{sup -1}), or elevated (600 {mu}mol mol{sup -1}) atmospheric CO{sub 2} concentration. A Free-Air CO{sub 2} Enrichment (FACE) system was used to maintain the elevated CO{sub 2} concentration whilst limiting experimental constraints on the field conditions. The theoretically predicted increase in the net rates of CO{sub 2} uptake per unit leaf area (A {mu}mol mol{sup -1}) as a conseq… more
Date: August 1, 1996
Creator: Hymus, G.J.
Partner: UNT Libraries Government Documents Department
open access

High-resolution spectroscopy using synchrotron radiation for surface structure determination and the study of correlated electron systems

Description: The surface structure of three molecular adsorbate systems on transition metal surfaces, ({radical}3 x {radical}3)R30{degrees} and (1.5 x 1.5)R18{degrees} CO adsorbed on Cu(111), and c(2x2) N2/Ni(100), have been determined using Angle-Resolved Photoemission Extended Fine Structure (ARPEFS). The adsorption site and bond lengths are reported for the adsorbate-metal bond and the first two substrate layers. The ARPEFS diffraction pattern of the shake-up peak for c(2x2) N2/Ni(100) is also discussed.… more
Date: May 1, 1996
Creator: Moler, E.J. Jr.
Partner: UNT Libraries Government Documents Department
open access

Practical Parallel Processing

Description: The physical limitations of uniprocessors and the real-time requirements of numerous practical applications have made parallel processing an essential technology in military, industry and scientific research. In this dissertation, we investigate parallelizations of three practical applications using three parallel machine models. The algorithms are: Finitely inductive (FI) sequence processing is a pattern recognition technique used in many fields. We first propose four parallel FI algorithms o… more
Date: August 1996
Creator: Zhang, Hua, 1954-
Partner: UNT Libraries
open access

Development of a high-resolution soft x-ray (30--1500 eV) beamline at the Advanced Light Source and its use for the study of angle-resolved photoemission extended fine structure

Description: ALS Bending magnet beamline 9.3.2 is for high resolution spectroscopy, with circularly polarized light. Fixed included-angle SGM uses three gratings for 30--1500 eV photons; circular polarization is produced by an aperture for selecting the beam above or below the horizontal plane. Photocurrent from upper and lower jaws of entrance slit sets a piezoelectric drive feedback loop on the vertically deflecting mirror for stable beam. End station has a movable platform. With photomeission data from S… more
Date: February 1, 1996
Creator: Huff, W. R. A.
Partner: UNT Libraries Government Documents Department
open access

NMR studies of DNA oligomers and their interactions with minor groove binding ligands

Description: The cationic peptide ligands distamycin and netropsin bind noncovalently to the minor groove of DNA. The binding site, orientation, stoichiometry, and qualitative affinity of distamycin binding to several short DNA oligomers were investigated by NMR spectroscopy. The oligomers studied contain A,T-rich or I,C-rich binding sites, where I = 2-desaminodeoxyguanosine. I{center_dot}C base pairs are functional analogs of A{center_dot}T base pairs in the minor groove. The different behaviors exhibited … more
Date: May 1, 1996
Creator: Fagan, P.A.
Partner: UNT Libraries Government Documents Department
open access

Simulation of a field scale tritium tracer experiment in a fractured, weathered shale using discrete-fracture/matrix-diffusion and equivalent porous medium models

Description: Simulations of a tritium tracer experiment in fractured shale saprolite, conducted at the Oak Ridge National Laboratory, were performed using 1D and 2D equivalent porous medium (EPM) and discrete-fracture/matrix-diffusion (DFMD) models. The models successfully reproduced the general shape of the breakthrough curves in down-gradient monitoring wells which are characterized by rapid first arrival, a slow-moving center of mass, and a persistent ``tail`` of low concentration. In plan view, the plum… more
Date: May 1, 1996
Creator: Stafford, Paige L.
Partner: UNT Libraries Government Documents Department
open access

Charge State Dependence of L-Shell X-Ray Production Cross Sections of ₂₈Ni, ₂₉Cu, ₃₀Zn, ₃₁Ga, and ₃₂Ge by Energetic Oxygen Ions

Description: Charge state dependence of L-shell x-ray production cross sections have been measured for 4-14 MeV ¹⁶O^q (q=3⁺-8⁺) ions incident on ultra-clean, ultra-thin copper, and for 12 MeV ¹⁶O^q (q=3⁺-8⁺) on nickel, zinc, gallium and germanium solid foils. L-shell x-ray production cross section were measured using target foils of thickness ≤0.6 μg/cm² evaporated onto 5 μg/cm² carbon backings. Oxygen ions at MeV energies and charge state q were produced using a 3MV 9SDH-2 National Electrostatics Corporati… more
Date: August 1996
Creator: Azordegan, Amir R. (Amir Reza)
Partner: UNT Libraries
Back to Top of Screen