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A Social History of Baytown, Texas, 1912-1956 (open access)

A Social History of Baytown, Texas, 1912-1956

Thesis discussing various aspects of the history of Baytown, Texas, based on recollections of community citizens and other primary sources.
Date: January 1958
Creator: Haenel, Olga Bernice Miller
System: The Portal to Texas History
[DGPC to DGA name change document] (open access)

[DGPC to DGA name change document]

A note from January 26, 1981 on the name change from the DGPC to the Dallas Gay Alliance.
Date: January 26, 1981
Creator: Dallas Gay Political Caucus
System: The UNT Digital Library
Separated-pair independent particle model and the generalized Brillouin theorem: ab initio calculations on the dissociation of polyatomic molecules (open access)

Separated-pair independent particle model and the generalized Brillouin theorem: ab initio calculations on the dissociation of polyatomic molecules

A method is developed to optimize the separated-pair independent particle (SPIP) wave function; it is a special case of the separated-pair theory obtained by using two-term natural expansions of the geminals. The orbitals are optimized by a theory based on the generalized Brillouin theorem and iterative configuration interaction (CI) calculations in the space of the SPIP function and its single excitations. The geminal expansion coefficients are optimized by serial 2 x 2 CI calculations. Formulas are derived for the matrix elements. An algorithm to implement the method is presented, and the work needed to evaluate the molecular integrals is discussed. (auth)
Date: January 1, 1976
Creator: Sundberg, K. R.
System: The UNT Digital Library
The Cryogenic Dark Matter Search and Background Rejection with Event Position Information (open access)

The Cryogenic Dark Matter Search and Background Rejection with Event Position Information

Evidence from observational cosmology and astrophysics indicates that about one third of the universe is matter, but that the known baryonic matter only contributes to the universe at 4%. A large fraction of the universe is cold and non-baryonic matter, which has important role in the universe structure formation and its evolution. The leading candidate for the non-baryonic dark matter is Weakly Interacting Massive Particles (WIMPs), which naturally occurs in the supersymmetry theory in particle physics. The Cryogenic Dark Matter Search (CDMS) experiment is searching for evidence of a WIMP interaction off an atomic nucleus in crystals of Ge and Si by measuring simultaneously the phonon energy and ionization energy of the interaction in the CDMS detectors. The WIMP interaction energy is from a few keV to tens of keV with a rate less than 0.1 events/kg/day. To reach the goal of WIMP detection, the CDMS experiment has been conducted in the Soudan mine with an active muon veto and multistage passive background shields. The CDMS detectors have a low energy threshold and background rejection capabilities based on ionization yield. However, betas from contamination and other radioactive sources produce surface interactions, which have low ionization yield, comparable to that of …
Date: January 1, 2005
Creator: Wang, Gen-sheng & U., /Case Western Reserve
System: The UNT Digital Library
Measurements of the Top Quark Pair Production Cross Section in Lepton + Jets Final States using a Topological Multivariate Technique as well as Lifetime b-Tagging in Proton - Anti-proton Collisions at s**(1/2)=1.96 TeV with the D0 Detector at the Tevatron (open access)

Measurements of the Top Quark Pair Production Cross Section in Lepton + Jets Final States using a Topological Multivariate Technique as well as Lifetime b-Tagging in Proton - Anti-proton Collisions at s**(1/2)=1.96 TeV with the D0 Detector at the Tevatron

Two alternative measurements of the t{bar t} production cross section at {radical}s = 1.96 TeV in proton-antiproton collisions in the lepton+jets channel are presented. The t{bar t} production cross section is extracted by combining the kinematic event information in a multivariate discriminant. The measurement yields {sigma}{sub p{bar p} {yields} t{bar t} + x} = 5.13{sub -1.57}{sup +1.76}(stat){sub -1.10}{sup +0.96}(syst) {+-} 0.33 (lumi) pb in the muon+jets channel, using 229.1 pb{sup -1}, and in the combination with the electron+jets channel 226.3 pb{sup -1} {sigma}{sub p{bar p} {yields} t{bar t} + x} = 6.60{sub -1.28}{sup +1.37}(stat){sub -1.11}{sup +1.25}(syst) {+-} 0.43 (lumi) pb. The second measurement presented reconstructs explicitly secondary vertices to d lifetime b-tagging. The measurement combines the muon+jets and the electron+jets channel, using 158.4 pb{sup -1} and 168.8 pb{sup -1}, respectively: {sigma}{sub p{bar p} {yields} t{bar t} + x} = 8.24{sub -1.25}{sup +1.34}(stat){sub -1.63}{sup +1.89}(syst) {+-} 0.54 (lumi) pb.
Date: January 1, 2005
Creator: Golling, Tobias F.
System: The UNT Digital Library
First measurement of the ratio of branching fractions BR(Lambda(b) to Lambda(c) mu nu)/BR(Lambda(b) to Lambda(c) pi) at CDF II (open access)

First measurement of the ratio of branching fractions BR(Lambda(b) to Lambda(c) mu nu)/BR(Lambda(b) to Lambda(c) pi) at CDF II

In this dissertation, we measure the properties of the lowest-mass beauty baryon, {Lambda}{sub b}. Baryons are the bound states of three quarks. Protons and neutrons, constituents of atomic nuclei, are the most common baryons. Other types of baryons can be produced and studied in the high-energy collider environment. Three-body dynamics makes baryons composed of low mass quarks difficult to study. On the other hand, baryons with one heavy quark simplify the theoretical treatment of baryon structure, since the heavy quark can be treated the same way as the nucleus in the atom. The {Lambda}{sub b} is composed of u, d, and b quarks, where the b quark is much heavier than the other two. Although, it is accessible, little is known about {Lambda}{sub b}. In 1991, UA1 [1] reconstructed 9 {+-} 1 {Lambda}{sub b} {yields} J/{Psi}{Lambda} candidates. In 1996, ALEPH and DELPHI reconstructed the decay {Lambda}{sub b} {yields} {Lambda}{sub c}{sup +}{pi}{sup -} and found only 3-4 candidates [2, 3]. ALEPH measured a {Lambda}{sub b} mass of 5614 {+-} 21 MeV/c{sup 2}, while DELPHI measured 5668 {+-} 18 MeV/c{sup 2}, about 2 {sigma} higher. Subsequently, CDF-I observed 20 {Lambda}{sub b} {yields} J/{Psi}{Lambda} events [4], confirmed the existence of {Lambda}{sub b} unambiguously …
Date: January 1, 2005
Creator: Yu, Shin-shan
System: The UNT Digital Library
A Measurement of Z Boson Production and Rapidity Distribution in p - anti-p Collisions at s**(1/2) = 1.96-TeV (open access)

A Measurement of Z Boson Production and Rapidity Distribution in p - anti-p Collisions at s**(1/2) = 1.96-TeV

High-precision measurements are made of Z boson production in proton-antiproton collisions at {radical}s = 1.96 TeV recorded by the Collider Detector at Fermilab, using the electron decay channel. The cross-section times branching ratio is measured to be {sigma}{sub Z} {center_dot} Br(Z {yields} e{sup +}e{sup -}) = (255.7 {+-} 2.4{sub stat} {+-} 5.2{sub sys} {+-} 15.2{sub lum})pb in a dataset of 194 pb{sup -1} collected between March 2002 and June 2003. This agrees well with theoretical predictions. The cross-section for W boson production in the electron channel has also been measured in the subset of this dataset of 72 pb{sup -1} collected up until January 2003. Using this smaller dataset the ratio of cross-sections is determined to be R {equivalent_to} {sigma}{sub W} {center_dot} Br(W {yields} e{nu})/{sigma}{sub Z} {center_dot} Br(Z {yields} ee) = 10.82 {+-} 0.18{sub stat} {+-} 0.16{sub sys}. Combining these results with measurements made in the muon channel gives R = 10.92 {+-} 0.15{sub stat} {+-} 0.14{sub sys} (e + {mu} channels), from which the branching ratio of the W to electrons and muons, and the total width of the W, have been extracted: Br(W {yields} {ell}{nu}) = 0.1089 {+-} 0.0022 ({ell} = e,{mu}); {Lambda}(W) = 2078.8 {+-} 41.4 MeV, …
Date: January 1, 2005
Creator: Robson, Aidan & U., /Oxford
System: The UNT Digital Library
Modelling the Shallow Water Equations in Curvilinear Coordinates with Physical Application (open access)

Modelling the Shallow Water Equations in Curvilinear Coordinates with Physical Application

The goal of this project is to provide the capability for simulating fluid flow on complicated geometries, such as in the Bahia de Todos Santos. The Bahia de Todos Santos is a bay situated in the northwest corner of Mexico, off the coast of Ensenada and south of San Diego, California, USA. Figure 1.1 shows the Bahia de Todos Santos. It is part of an image taken from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors on the Aqua and Terra satellites in late June and early July 2003 [8]. Roughly 200 square kilometers in size, the bay also contains two islands off the peninsula of Punta Banda. Characteristics of flow in this bay are driven by the moon tide (M2) and wind forcing [9].
Date: January 12, 2005
Creator: Wingenter, S
System: The UNT Digital Library
A search for anomalous heavy - flavor quark production in association with W bosons (open access)

A search for anomalous heavy - flavor quark production in association with W bosons

None
Date: January 1, 2005
Creator: Fisher, Wade Cameron
System: The UNT Digital Library
A Measurement of the mass of the Top Quark in the di-lepton channels using the D0 Detector at Fermilab (open access)

A Measurement of the mass of the Top Quark in the di-lepton channels using the D0 Detector at Fermilab

This dissertation describes a measurement of the mass of the top quark using events consistent with the hypothesis t{bar t} {yields} bW{sup +} {bar b}W{sup -} {yields} bl{sup +}{nu}{bar b}l{sup -}{bar {nu}}, where (l=e,{mu}). The events are obtained from nearly 230 pb{sup -1} of p{bar p} collision data collected by the D0 experiment between 2002 and 2004 during Run II. In this decay channel two neutrinos remain undetected. Extraction of the mass of the top quark by kinematic reconstruction is not possible because the event is under-constrained. Therefore, a dynamical likelihood method is developed to obtain the mass of the top quark. The mass of top quark obtained from the candidate events selected in the di-electron channel and the e{mu} channel is: 154.1 {sup +14.2}{sub -12.8}(stat.) {+-}6.6 (syst.) GeV.
Date: January 1, 2005
Creator: Fatakia, Sarosh Noshir & U., /Boston
System: The UNT Digital Library
Study of the doubly and singly Cabibbo suppressed decays D+ --> K+ pi- pi+ and D(s)+ --> K+ pi- pi+ in the FOCUS experiment (open access)

Study of the doubly and singly Cabibbo suppressed decays D+ --> K+ pi- pi+ and D(s)+ --> K+ pi- pi+ in the FOCUS experiment

This thesis illustrates a complete study of the doubly and singly Cabibbo suppressed decays D{sup +} and D{sub s}{sup +} {yields} K{sup +} {pi}{sup -}{pi}{sup +}. Data for this analysis have been collected by the fixed-target high-energy photoproduction experiment FOCUS at Fermilab. The authors have selected the D{sup +} and D{sub s}{sup +} samples with cuts to obtain a sufficiently high statistics, a good signal to noise ratio and, at the same time, eliminate possible contaminations from the more copious and favored decays. The D{sup +} yield consists of 189 {+-} 24 events, with a signal to noise ratio {approx} 1; the D{sub s}{sup +} yield is 567 {+-} 31 and the signal to noise ratio is {approx} 2.5. The authors have measured {Lambda}(D{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +})/{Lambda}(D{sup +} {yields} K{sup -}{pi}{sup +}{pi}{sup +}) = 0.0065 {+-} 0.0008 {+-} 0.004 and {Lambda}(D{sub s}{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +})/{Lambda}(D{sub s}{sup +} {yields} K{sup +}K{sup -}{pi}{sup +}) = 0.127 {+-} 0.007 {+-} 0.014, improving the previous determinations of a factor of 2 and 5, respectively. The author has also performed a Dalitz plot analysis for both decays. The amplitude analysis for D{sub s}{sup +} {yields} K{sup +}{pi}{sup -}{pi}{sup +} …
Date: January 1, 2005
Creator: Edera, Laura & U., /Milan
System: The UNT Digital Library
Calculation of transport coefficients in an axisymmetric plasma (open access)

Calculation of transport coefficients in an axisymmetric plasma

A method of calculating the transport coefficient in an axisymmetric toroidal plasma is presented. This method is useful in calculating the transport coefficients in a Tokamak plasma confinement device. The particle density and temperature are shown to be a constant on a magnetic flux surface. Transport equations are given for the total particle flux and total energy flux crossing a closed toroidal surface. Also transport equations are given for the toroidal magnetic flux. A computer code was written to calculate the transport coefficients for a three species plasma, electrons and two species of ions. This is useful for calculating the transport coefficients of a plasma which contains impurities. It was found that the particle and energy transport coefficients are increased by a large amount, and the transport coefficients for the toroidal magnetic field are reduced by a small amount.
Date: January 1977
Creator: Shumaker, Dana E.
System: The UNT Digital Library
Cubic Spline Collocation Method for the Simulation of Turbulent Thermal Convection in Compressible Fluids (open access)

Cubic Spline Collocation Method for the Simulation of Turbulent Thermal Convection in Compressible Fluids

A collocation method using cubic splines is developed and applied to simulate steady and time-dependent, including turbulent, thermally convecting flows for two-dimensional compressible fluids. The state variables and the fluxes of the conserved quantities are approximated by cubic splines in both space direction. This method is shown to be numerically conservative and to have a local truncation error proportional to the fourth power of the grid spacing. A ''dual-staggered'' Cartesian grid, where energy and momentum are updated on one grid and mass density on the other, is used to discretize the flux form of the compressible Navier-Stokes equations. Each grid-line is staggered so that the fluxes, in each direction, are calculated at the grid midpoints. This numerical method is validated by simulating thermally convecting flows, from steady to turbulent, reproducing known results. Once validated, the method is used to investigate many aspects of thermal convection with high numerical accuracy. Simulations demonstrate that multiple steady solutions can coexist at the same Rayleigh number for compressible convection. As a system is driven further from equilibrium, a drop in the time-averaged dimensionless heat flux (and the dimensionless internal entropy production rate) occurs at the transition from laminar-periodic to chaotic flow. This observation is …
Date: January 12, 2005
Creator: Castillo, V M
System: The UNT Digital Library
Photoproduction of the K+ K0-(1750) (open access)

Photoproduction of the K+ K0-(1750)

While photoproduction has often been advertised as an important environment in which to study light meson spectroscopy, solid experimental results are sparse. In fact, beyond the relatively straightforward photoproduction of the {rho}, {omega}, and {phi} mesons, the few results of exclusive photoproduction that do exist are poorly understood, and several, perhaps, have even been misinterpreted. After extensively reviewing the sometimes tenuous history of the exclusive photoproduction of the ''{rho}{sup 1}(1600)'', the ''{omega}{pi}{sup 0}(1250)'', the ''{omega}(1650)'', and the ''K{sup +}K{sup -}(1750)'', new results from the E831/FOCUS photoproduction experiment at Fermilab are presented which address the interpretation of the K{sup +}K{sup -}(1750). This enhancement in low-p{sub T} K{sup +}K{sup -} pairs at a mass near 1750 MeV/c{sup 2} has been observed by several previous photoproduction experiments, but, despite several apparent inconsistencies, it has always been interpreted as the J{sup PC} = 1{sup --} {phi}(1680) meson. With nearly two orders of magnitude more events than any previous observation of the K{sup +}K{sup -}(1750), and based on precise measurements of its mass and width, and its absence from the K*K final state, the FOCUS data can finally render this interpretation implausible. In addition, several steps have been taken towards establishing a new interpretation. Based …
Date: January 1, 2003
Creator: Mitchell, Ryan Edward & U., /Tennessee
System: The UNT Digital Library
Extending the Sensitivity to the Detection of WIMP Dark Matter with an Improved Understanding of the Limiting Neutron Backgrounds (open access)

Extending the Sensitivity to the Detection of WIMP Dark Matter with an Improved Understanding of the Limiting Neutron Backgrounds

The Cryogenic Dark Matter Search (CDMS) uses position-sensitive Germanium and Silicon crystals in the direct detection of Weakly Interacting Massive Particles (WIMPs) believed to constitute most of the dark matter in the Universe. WIMP interactions with matter being rare, identifying and eliminating known backgrounds is critical for detection. Event-by-event discrimination by the detectors rejects the predominant gamma and beta backgrounds while Monte Carlo simulations help estimate, and subtract, the contribution from the neutrons. This thesis describes the effort to understand neutron backgrounds as seen in the two stages of the CDMS search for WIMPs. The first stage of the experiment was at a shallow site at the Stanford Underground Facility where the limiting background came from high-energy neutrons produced by cosmic-ray muon interactions in the rock surrounding the cavern. Simulations of this background helped inform the analysis of data from an experimental run at this site and served as input for the background reduction techniques necessary to set new exclusion limits on the WIMP-nucleon cross-section, excluding new parameter space for WIMPs of masses 8-20 GeV/c{sup 2}. This thesis considers the simulation methods used as well as how various event populations in the data served as checks on the simulations to …
Date: January 1, 2005
Creator: Kamat, Sharmila & U., /Case Western Reserve
System: The UNT Digital Library
Comparison between phase shift derived and exactly calculated nucleon--nucleon interaction matrix elements. [Tables] (open access)

Comparison between phase shift derived and exactly calculated nucleon--nucleon interaction matrix elements. [Tables]

A comparison is made between matrix elements calculated using the uncoupled channel Sussex approach to second order in DWBA and matrix elements calculated using a square well potential. The square well potential illustrated the problem of the determining parameter independence balanced with the concept of phase shift difference. The supersoft core potential was used to discuss the systematics of the Sussex approach as a function of angular momentum as well as the relation between Sussex generated and effective interaction matrix elements. In the uncoupled channels the original Sussex method of extracting effective interaction matrix elements was found to be satisfactory. In the coupled channels emphasis was placed upon the /sup 3/S/sub 1/-/sup 3/D/sub 1/ coupled channel matrix elements. Comparison is made between exactly calculated matrix elements, and matrix elements derived using an extended formulation of the coupled channel Sussex method. For simplicity the potential used is a nonseparable cut-off oscillator. The eigenphases of this potential can be made to approximate the realistic nucleon-nucleon phase shifts at low energies. By using the cut-off oscillator test potential, the original coupled channel Sussex method of determining parameter independence was shown to be incapable of accurately reproducing the exact cut-off oscillator matrix elements. The …
Date: January 1, 1975
Creator: Gregersen, A. W.
System: The UNT Digital Library
Large-Eddy Simulation of the Evolving Stable Boundary Layer Over Flat Terrain (open access)

Large-Eddy Simulation of the Evolving Stable Boundary Layer Over Flat Terrain

The stable boundary layer (SBL) in the atmosphere is of considerable interest because it is often the worse case scenario for air pollution studies and health effect assessments associated with the accidental release of toxic material. Traditional modeling approaches used in such studies do not simulate the non-steady character of the velocity field, and hence often overpredict concentrations while underpredicting spatial coverage of potentially harmful concentrations of airborne material. The challenge for LES is to be able to resolve the rather small energy-containing eddies of the SBL while still maintaining an adequate domain size. This requires that the subgrid-scale (SGS) parameterization of turbulence incorporate an adequate representation of turbulent energy transfer. Recent studies have shown that both upscale and downscale energy transfer can occur simultaneously, but that overall the net transfer is downscale. Including the upscale transfer of turbulent energy (energy backscatter) is particularly important near the ground and under stably-stratified conditions. The goal of this research is to improve the ability to realistically simulate the SBL. The large-eddy simulation (LES) approach with its subgrid-scale (SGS) turbulence model does a better job of capturing the temporally and spatially varying features of the SBL than do Reynolds-averaging models. The scientific objectives …
Date: January 2, 2002
Creator: Townsend, Richard Townsend
System: The UNT Digital Library
Effect of Atmospher on Interfacial Reactions and Wetting Behavior of Glass-Metal Systems (open access)

Effect of Atmospher on Interfacial Reactions and Wetting Behavior of Glass-Metal Systems

None
Date: January 1, 1971
Creator: Hoge, Carl E
System: The UNT Digital Library
Low frequency ultrasonic nondestructive inspection of aluminum/adhesive fuselage lap splices (open access)

Low frequency ultrasonic nondestructive inspection of aluminum/adhesive fuselage lap splices

This thesis is a collection of research efforts in ultrasonics, conducted at the Center for Aviation Systems Reliability located at Iowa State University, as part of the Federal Aviation Administration`s ``Aging Aircraft Program.`` The research was directed toward the development of an ultrasonic prototype to inspect the aluminum/adhesive fuselage lap splices found on 1970`s vintage Boeing passenger aircraft. The ultrasonic prototype consists of a normal incidence, low frequency inspection technique, and a scanning adapter that allows focused immersion transducers to be operated in a direct contact manner in any inspection orientation, including upside-down. The inspection technique uses a computer-controlled data acquisition system to produce a C-scan image of a radio frequency (RF) waveform created by a low frequency, broadband, focused beam transducer, driven with a spike voltage pulser. C-scans produced by this technique are color representations of the received signal`s peak-to-peak amplitude (voltage) taken over an (x, y) grid. Low frequency, in this context, refers to a wavelength that is greater than the lap splice`s layer thicknesses. With the low frequency technique, interface echoes of the lap splice are not resolved and gating of the signal is unnecessary; this in itself makes the technique simple to implement and saves considerable …
Date: January 4, 1994
Creator: Patton, T.
System: The UNT Digital Library
Isotopic tracer studies of Fischer-Tropsch Synthesis over Ru/TiO{sub 2} catalysts (open access)

Isotopic tracer studies of Fischer-Tropsch Synthesis over Ru/TiO{sub 2} catalysts

Fischer-Tropsch synthesis is a process in which CO and H{sub 2} react to give predominantly liquid hydrocarbons. The reaction can be considered a special type of polymerization in which the monomer is produced in situ, and chain growth occurs by a sequence of independently repeated additions of the monomer to the growing chain. A investigation has been conducted to study the CO hydrogenation reaction in order to better understand catalyst deactivation and the elementary surface processes involved in chain growth. Isotopic tracers are used in conjunction with transient-response techniques in this study of Fischer-Tropsch synthesis over Ru/TiO{sub 2} catalysts. Experiments are conducted at a total pressure of 1 atmosphere, reaction temperatures of 453--498 K and D{sub 2}/CO (or H{sub 2}/CO) ratios of 2--5. Synthesis products are analyzed by gas chromatography or isotope-ratio gas chromatography-mass spectrometry. Rate constants for chain initiation, propagation and termination are evaluated under steady-state reaction conditions by using transients in isotopic composition. The activation energy for chain termination is much higher than that for propagation, accounting for the observed decrease in the chain growth parameter are also estimated. Coverages by reaction intermediates are also estimated. When small amounts of {sup 12}C-labelled ethylene are added to {sup 13}CO/H{sub …
Date: January 1, 1992
Creator: Krishna, K. R.
System: The UNT Digital Library
Sequence modelling and an extensible data model for genomic database (open access)

Sequence modelling and an extensible data model for genomic database

The Human Genome Project (HGP) plans to sequence the human genome by the beginning of the next century. It will generate DNA sequences of more than 10 billion bases and complex marker sequences (maps) of more than 100 million markers. All of these information will be stored in database management systems (DBMSs). However, existing data models do not have the abstraction mechanism for modelling sequences and existing DBMS`s do not have operations for complex sequences. This work addresses the problem of sequence modelling in the context of the HGP and the more general problem of an extensible object data model that can incorporate the sequence model as well as existing and future data constructs and operators. First, we proposed a general sequence model that is application and implementation independent. This model is used to capture the sequence information found in the HGP at the conceptual level. In addition, abstract and biological sequence operators are defined for manipulating the modelled sequences. Second, we combined many features of semantic and object oriented data models into an extensible framework, which we called the ``Extensible Object Model``, to address the need of a modelling framework for incorporating the sequence data model with other types …
Date: January 1, 1992
Creator: Li, Peter Wei-Der
System: The UNT Digital Library
Perturbation theory in light-cone quantization (open access)

Perturbation theory in light-cone quantization

A thorough investigation of light-cone properties which are characteristic for higher dimensions is very important. The easiest way of addressing these issues is by analyzing the perturbative structure of light-cone field theories first. Perturbative studies cannot be substituted for an analysis of problems related to a nonperturbative approach. However, in order to lay down groundwork for upcoming nonperturbative studies, it is indispensable to validate the renormalization methods at the perturbative level, i.e., to gain control over the perturbative treatment first. A clear understanding of divergences in perturbation theory, as well as their numerical treatment, is a necessary first step towards formulating such a program. The first objective of this dissertation is to clarify this issue, at least in second and fourth-order in perturbation theory. The work in this dissertation can provide guidance for the choice of counterterms in Discrete Light-Cone Quantization or the Tamm-Dancoff approach. A second objective of this work is the study of light-cone perturbation theory as a competitive tool for conducting perturbative Feynman diagram calculations. Feynman perturbation theory has become the most practical tool for computing cross sections in high energy physics and other physical properties of field theory. Although this standard covariant method has been applied …
Date: January 1, 1992
Creator: Langnau, A.
System: The UNT Digital Library
Encapsulation of Hazardous Wastes Into Agglomerates (open access)

Encapsulation of Hazardous Wastes Into Agglomerates

The objective of this study was to investigate the feasibility of using the cementitious properties and agglomeration characteristics of coal conversion byproducts to encapsulate and immobilize hazardous waste materials. The intention was to establish an economical way of co-utilization and co-disposal of wastes. In addition, it may aid in the eradication of air pollution problems associated with the fine-powdery nature of fly ash. Encapsulation into agglomerates is a novel approach of treating toxic waste. Although encapsulation itself is not a new concept, existing methods employ high-cost resins that render them economically unfeasible. In this investigation, the toxic waste was contained in a concrete-like matrix whereby fly ash and other cementitious waste materials were utilized. The method incorporates the principles of solidification, stabilization and agglomeration. Another aspect of the study is the evaluation of the agglomeration as possible lightweight aggregates. Since fly ash is commercially used as an aggregate, it would be interesting to study the effect of incorporating toxic wastes in the strength development of the granules. In the investigation, the fly ash self-cementation process was applied to electroplating sludges as the toxic waste. The process hoped to provide a basis for delisting of the waste as hazardous and, thereby …
Date: January 28, 1992
Creator: Guloy, Aida
System: The UNT Digital Library
A comparative evaluation of conceptual models for the Snake River Plain aquifer at the Idaho Chemical Processing Plant, INEL (open access)

A comparative evaluation of conceptual models for the Snake River Plain aquifer at the Idaho Chemical Processing Plant, INEL

Geologic and hydrologic data collected by the United States Geological Survey (USGS) are used to evaluate the existing ground water monitoring well network completed in the upper portion of the Snake River Plain aquifer (SRPA) beneath the Idaho Chemical Processing Plant (ICPP). The USGS data analyzed and compared in this study include: (a) lithologic, geophysical, and stratigraphic information, including the conceptual geologic models intrawell, ground water flow measurement (Tracejector tests) and (c) dedicated, submersible, sampling group elevations. Qualitative evaluation of these data indicate that the upper portion of the SRPA is both heterogeneous and anisotropic at the scale of the ICPP monitoring well network. Tracejector test results indicate that the hydraulic interconnection and spatial configuration of water-producing zones is extremely complex within the upper portion of the SRPA. The majority of ICPP monitoring wells currently are equipped to sample ground water only the upper lithostratigraphic intervals of the SRPA, primarily basalt flow groups E, EF, and F. Depth-specific hydrogeochemical sampling and analysis are necessary to determine if ground water quality varies significantly between the various lithostratigraphic units adjacent to individual sampling pumps.
Date: January 1, 1992
Creator: Prahl, C. J.
System: The UNT Digital Library