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Trace Elemental Analysis of Ashes in the Combustion of the Binder Enhanced d-RDF by Inductively Coupled Plasma Atomic Emission Spectroscopy

Description: Incineration is an attractive solution to the problems of disposing of municipal solid wastes and supplying energy. Because up to 25 percent of the waste in refuse-derived-fuel systems is ash, the physical and chemical characteristics of ash become more and more important for its potential impacts and methods suitable for their disposal. Trace elements concentration in ash is of great interest because of its relationship to regulatory criteria under the Resource Conservation and Recovery Act (R… more
Date: November 1988
Creator: Tai, Chia-Hui
Partner: UNT Libraries
open access

NMR Studies of Liquid Crystals and Molecules Dissolved in Liquid Crystal Solvents

Description: This thesis describes several studies in which nuclear magnetic resonance (nmr) spectroscopy has been used to probe the structure, orientation and dynamics of liquid crystal mesogens and molecules dissolved in liquid crystalline phases. In addition, a modern high field nmr spectrometer is described which has been used to perform such nmr studies. Chapter 1 introduces the quantum mechanical formalisms used throughout this thesis and briefly reviews the fundamentals of nuclear spin physics and pu… more
Date: November 1, 1982
Creator: Drobny, G. P.
Partner: UNT Libraries Government Documents Department
open access

Multiple-Quantum NMR in Solids

Description: Time domain multiple-quantum (MQ) nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for spectral simplification and for providing new information on molecular dynamics. In this thesis, applications of MQ NMR are presented and show distinctly the advantages of this method over the conventional single-quantum NMR. Chapter 1 introduces the spin Hamiltonians, the density matrix formalism and some basic concepts of MQ NMR spectroscopy. In chapter 2, {sup 14}N double-quantum coherence … more
Date: November 1, 1982
Creator: Yen, Y-S.
Partner: UNT Libraries Government Documents Department
open access

The Indiana Fine Arts Diagnostic Achievement Tests

Description: A document on the Indiana Fine Arts Diagnostic Achievement Tests, The Getty Center for Education in the Arts Student Assessment Meeting. The Indiana Fine Arts Diagnostic Achievement Testing program began in 1987 as a means to provide art teachers with new tools from which to measure student achievement in visual arts, music, theatre/creative drama and dance/creative movement. The purpose of the testing program is also to create / develop new tools to diagnose student and class strengths or need… more
Date: [1989-11-04,1989-11-06]
Creator: Patchen, Jeffrey H.
Partner: UNT Libraries Special Collections
open access

Transient and temperature-dependent phenomena in Ge:Be and Ge:Zn far infrared photoconductors

Description: An experimental study of the transient and temperature-dependent behavior of Ge:Be and Ge:Zn photoconductors has been performed under the low background photon flux conditions (p dot approx. = 10/sup 8/ photons/second) typical of astronomy and astrophysics applications. The responsivity of Ge:Be and Ge:Zn detectors is strongly temperature-dependent in closely compensated material, and the effect of compensation on free carrier lifetime in Ge:Be has been measured using the photo-Hall effect tech… more
Date: November 1985
Creator: Haegel, Nancy Marie
Partner: UNT Libraries Government Documents Department
open access

Time-domain multiple-quantum NMR

Description: The development of time-domain multiple-quantum nuclear magnetic resonance is reviewed through mid 1982 and some prospects for future development are indicated. Particular attention is given to the problem of obtaining resolved, interpretable, many-quantum spectra for anisotropic magnetically isolated systems of coupled spins. New results are presented on a number of topics including the optimization of multiple-quantum-line intensities, analysis of noise in two-dimensional spectroscopy, and th… more
Date: November 1, 1982
Creator: Weitekamp, D.P.
Partner: UNT Libraries Government Documents Department
open access

A Comparison of Meansort and Quicksort

Description: The main purpose of this project is to compare a new sorting method- Meansort with its preceding sorting method- Quicksort. Meansort uses the mean value for each key to determine the partition of the file, but Quicksort selects at random. Experiments proved that in some ways Meansort is superior to Quicksort but is still not perfect since it always needs a mean value for each key. This project implements these two methods and determines the situations under which each of these methods outperfor… more
Date: November 1985
Creator: Tsang, Pey Betty
Partner: UNT Libraries
open access

The Data Structure of a KSAM Key Directory

Description: The purpose of this project is to explore the alternate data structures for a disk file which is currently a preorder binary tree. specifically, the file is the key directory for an implementation of Keyed Sequential Access Method (KSAM) in a mini-computer operating system. A new data structure will be chosen, with the reasons for that choice given, and it will be incorporated into the existing system.
Date: November 1980
Creator: Kirchoff, Deanna T.
Partner: UNT Libraries
open access

Selectivity in multiple quantum nuclear magnetic resonance

Description: The observation of multiple-quantum nuclear magnetic resonance transitions in isotropic or anisotropic liquids is shown to give readily interpretable information on molecular configurations, rates of motional processes, and intramolecular interactions. However, the observed intensity of high multiple-quantum transitions falls off dramatically as the number of coupled spins increases. The theory of multiple-quantum NMR is developed through the density matrix formalism, and exact intensities are … more
Date: November 1, 1980
Creator: Warren, W. S.
Partner: UNT Libraries Government Documents Department
open access

Vibrational state-resolved differential cross sections for the D + H sub 2 yields DH + H reaction

Description: In this thesis, crossed-molecular-beams studies of the reaction D + H{sub 2} {yields} DH + H at collision energies of 0.53 and 1.01 eV are reported. Chapter 1 provides a survey of important experimental and theoretical studies on the dynamics of the hydrogen exchange reaction. Chapter 2 discusses the development of the excimer-laser photolysis D atom beam source that was used in these studies and preliminary experiments on the D + H{sub 2} reaction. In Chapter 3, the differential cross section … more
Date: November 1, 1989
Creator: Continetti, Robert Elliot
Partner: UNT Libraries Government Documents Department
open access

A small low energy cyclotron for radioisotope measurements

Description: Direct detection of {sup 14}C by accelerator mass spectrometry has proved to be a much more sensitive method for radiocarbon dating than the decay counting method invented earlier by Libby. A small cyclotron (the cyclotrino'') was proposed for direct detection of radiocarbon in 1980. This combined the suppression of background through the use of negative ions, which had been used effectively in tandem accelerators, with the high intrinsic mass resolution of a cyclotron. Development of a small e… more
Date: November 1, 1989
Creator: Bertsche, Kirk Joseph
Partner: UNT Libraries Government Documents Department
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