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Polk County Enterprise (Livingston, Tex.), Vol. 121, No. 2, Ed. 1 Sunday, January 5, 2003 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 121, No. 2, Ed. 1 Sunday, January 5, 2003

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: January 5, 2003
Creator: White, Barbara
Object Type: Newspaper
System: The Portal to Texas History
Archer County News (Archer City, Tex.), No. 23, Ed. 1 Thursday, June 5, 2003 (open access)

Archer County News (Archer City, Tex.), No. 23, Ed. 1 Thursday, June 5, 2003

Weekly newspaper from Archer City, Texas that includes local, state, and national news along with advertising.
Date: June 5, 2003
Creator: Lewis, Shelley
Object Type: Newspaper
System: The Portal to Texas History
ALS user meeting features 10th anniversary celebration (open access)

ALS user meeting features 10th anniversary celebration

The Advanced Light Source (ALS) saw first light on October 5, 1993, not quite to the day but close to 10 years before the 2003 ALS Users Association meeting, held October 6-8. Fittingly, the proceedings included retrospectives from two of the key players in the early history of the ALS, David Attwood and Jay Marx, and a display of photographs chronicling its construction and commissioning. Science highlights, highlights from young researchers, and posters constituted the meat of the program on Monday and Tuesday morning, while workshops took over Tuesday afternoon and all day Wednesday.
Date: December 5, 2003
Creator: Robinson, Art
Object Type: Article
System: The UNT Digital Library
Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf San Andres Reservoir. Annual Report: August 3, 2000--August 2, 2001 (open access)

Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf San Andres Reservoir. Annual Report: August 3, 2000--August 2, 2001

The OXY-operated Class 2 Project at West Welch is designed to demonstrate how the use of advanced technology can improve the economics of miscible CO{sub 2} injection projects in lower quality Shallow Shelf Carbonate reservoirs. The research and design phase (Budget Period 1) primarily involved advanced reservoir characterization. The current demonstration phase (Budget Period 2) is the implementation of the reservoir management plan for an optimum miscible CO{sub 2} flood design based on the reservoir characterization. Although Budget Period 1 for the Project officially ended 12/31/96, reservoir characterization and simulation work continued during the Budget Period 2. During the seventh annual reporting period (8/3/00-8/2/01) covered by this report, work continued on interpretation of the interwell seismic data to create porosity and permeability profiles which were distributed into the reservoir geostatistically. The initial interwell seismic CO{sub 2} monitor survey was conducted and the acquired data processed and interpretation started. Only limited well work and facility construction were conducted in the project area. The CO{sub 2} injection initiated in October 1997 was continued, although the operator had to modify the operating plan in response to low injection rates, well performance and changes in CO{sub 2} supply. CO{sub 2} injection was focused in …
Date: May 5, 2003
Creator: Beebe, Tom
Object Type: Report
System: The UNT Digital Library
Studies of the N=90 region: The decay of 154Eu to 154Gd (open access)

Studies of the N=90 region: The decay of 154Eu to 154Gd

The decay of {sup 154}Eu {yields} {sup 154}Gd has been studied by {gamma}-ray singles and {gamma}-{gamma} coincidence spectroscopy using an array of 20 Compton-suppressed Ge detectors. The primary goal of the work was to confirm or refute a large number of questionable features in the decay scheme: the outcome is the removal of 8 levels from the previously adopted scheme, with the result that a new type of collective band is revealed. Many weak decay branches for the decay are clarified. These results are critical for understanding the structure of {sup 154}Gd and the N = 90 isotones; and the improved completeness of the decay scheme contributes to the use of {sup 154}Eu as a metrological standard.
Date: December 5, 2003
Creator: Kulp, W. D.; Wood, J. L.; Krane, K. S.; Loats, J.; Schmelzenbach, P.; Stapels, C. J. et al.
Object Type: Article
System: The UNT Digital Library
Foaming and Antifoaming in Radioactive Waste Pretreatment and Immobilization Processes (open access)

Foaming and Antifoaming in Radioactive Waste Pretreatment and Immobilization Processes

The objective of this research is to develop a fundamental understanding of the physico-chemical mechanisms that cause foaminess in the DOE High Level (HLW) and Low Activity radioactive waste separation processes and to develop and test advanced antifoam/defoaming agents. Antifoams developed for this research will be tested using simulated defense HLW radioactive wastes obtained from the Hanford and Savannah River sites.
Date: June 5, 2003
Creator: Wasan, Darsh T.; Nikolov, Alex; Lambert, Dan & Calloway, T. Bond, Jr.
Object Type: Report
System: The UNT Digital Library
Atomic resolution of lithium ions in LiCoO{sub 2} (open access)

Atomic resolution of lithium ions in LiCoO{sub 2}

LiCoO{sub 2} is the most common lithium storage material used as positive electrode in lithium rechargeable batteries. Ordering of lithium and vacancies has a profound effect on the physical properties of Li{sub x}CoO{sub 2} and the electrochemical performances of lithium batteries. An exit surface wave (ESW) phase image reconstructed from experimental images obtained on the LBNL One-Angstrom Microscope (OAM) shows all three types of atoms in LiCoO{sub 2}.
Date: June 5, 2003
Creator: Shao-Horn, Yang; Croguennec, Laurence; Delmas, Claude; Nelson, E. Chris & O'Keefe, Michael A.
Object Type: Article
System: The UNT Digital Library
Miscoding properties of 1,N{sup 6}-ethanoadenine, a DNA adduct derived from reaction with antitumor agent 1,3-bis(2-chloroethyl)-1-nitrosourea (open access)

Miscoding properties of 1,N{sup 6}-ethanoadenine, a DNA adduct derived from reaction with antitumor agent 1,3-bis(2-chloroethyl)-1-nitrosourea

1,N{sup 6}-Ethanoadenine (EA) is an exocyclic adduct formed from DNA reaction with the antitumor agent, 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). To understand the role of this adduct in the mechanism of mutagenicity or carcinogenicity by BCNU, an oligonucleotide with a site-specific EA was synthesized using phosphoramidite chemistry. We now report the in vitro miscoding properties of EA in translesion DNA synthesis catalyzed by mammalian DNA polymerases (pols) {alpha}, {beta}, {eta} and {iota}. These data were also compared with those obtained for the structurally related exocyclic adduct, 1,N{sup 6}-ethenoadenine ({var_epsilon}A). Using a primer extension assay, both pols {alpha} and {beta} were primarily blocked by EA or {var_epsilon}A with very minor extension. Pol {eta} a member of the Y family of polymerases, was capable of catalyzing a significant amount of bypass across both adducts. Pol {eta} incorporated all four nucleotides opposite EA and {var_epsilon}A, but with differential preferences and mainly in an error-prone manner. Human pol {iota}, a paralog of human pol {eta}, was blocked by both adducts with a very small amount of synthesis past {var_epsilon}A. It incorporated C and, to a much lesser extent, T, opposite either adduct. In addition, the presence of an A adduct, e.g. {var_epsilon}A, could affect the specificity of …
Date: March 5, 2003
Creator: Hang, Bo; Guliaev, Anton B.; Chenna, Ahmed & Singer, B.
Object Type: Article
System: The UNT Digital Library
Efficient airflow design for cleanrooms improves business bottom lines (open access)

Efficient airflow design for cleanrooms improves business bottom lines

Based on a review of airflow design factors and in-situ energy measurements in ISO Cleanliness Class-5 cleanrooms, this paper addresses the importance of energy efficiency in airflow design and opportunities of cost savings in cleanroom practices. The paper discusses design factors that can long lastingly affect cleanroom system performance, and demonstrates benefits of energy efficient cleanroom design from viewpoints of environmental control and business operations. The paper suggests that a high performance cleanroom should not only be effective in contamination control, but also be efficient in energy and environmental performance. The paper also suggests that energy efficient design practice stands to bring in immediate capital cost savings and operation cost savings, and should be regarded by management as a strategy to improve business bottom lines.
Date: January 5, 2003
Creator: Xu, Tengfang
Object Type: Article
System: The UNT Digital Library
DEVELOPMENT PRACTICES FOR OPTIMIZED MEOR IN SHALLOW HEAVY OIL RESERVOIRS (open access)

DEVELOPMENT PRACTICES FOR OPTIMIZED MEOR IN SHALLOW HEAVY OIL RESERVOIRS

The objective of this research project is to demonstrate an economically viable and sustainable method of producing shallow heavy oil reserves in western Missouri and southeastern Kansas, using an integrated approach including surface geochemical surveys, conventional MEOR treatments, horizontal fracturing in vertical wells, electrical resistivity tomography (ERT), and reservoir simulation to optimize the recovery process. The objective also includes transferring the knowledge gained from the project to other local landowners, to demonstrate how they may identify and develop their own heavy oil resources with minimal capital investment. Tasks completed in the first six-month period include soil sampling, geochemical analysis, construction of ERT arrays, collection of background ERT surveys, and analysis of core samples to develop a geomechanical model for designing the hydraulic fracturing treatment. Five wells were to be drilled in phase I. However, weather and funding delays resulted in drilling shifting to the second phase of the project. Work performed to date demonstrates that surface geochemical methods can be used to differentiate between productive and non-productive areas of the Warner Sand and that ERT can be used to successfully image through the Warner Sand.
Date: September 5, 2003
Creator: Dunn-Norman, Shari
Object Type: Report
System: The UNT Digital Library
Improved Miscible Nitrogen Flood Performance Utilizing Advanced Reservoir Characterization and Horizontal Laterals in a Class I Reservoir - East Binger (Marchand) Unit Quarterly Report (open access)

Improved Miscible Nitrogen Flood Performance Utilizing Advanced Reservoir Characterization and Horizontal Laterals in a Class I Reservoir - East Binger (Marchand) Unit Quarterly Report

Implementation of the work program of Budget Period 2 of the East Binger Unit (''EBU'') DOE Project is progressing and nearing completion. EBU 63-2H has been drilled, completed, and brought on line. This is the second of three horizontal wells planned for this Budget Period, but based on the costs and performances to date of all new wells, could be the last. It will take some time to evaluate their impact on sweep and ultimate recovery. In addition to the drilling of new wells, the project also includes conversions of five wells from producers to injectors. Three wells were previously converted, and a fourth, EBU 37-3H, was prepared for conversion at the end of this reporting period. The fifth will require an expensive workover and will be re-evaluated. Project response to the various projects continues to be very favorable. Gas injection into the pilot area has increased from 4.0 MMscf/d prior to development to an average 7.3 MMscf/d in this reporting period, while gas production has actually decreased from 4.1 MMscf/d to 3.9 MMscf/d. The nitrogen content of produced gas has dropped from 58% to 52%. This has reduced the nitrogen recycle within the pilot area from 60% to 27%. …
Date: November 5, 2003
Creator: Sinner, Joe
Object Type: Report
System: The UNT Digital Library
CALIBRATION OF ONLINE ANALYZERS USING NEURAL NETWORKS (open access)

CALIBRATION OF ONLINE ANALYZERS USING NEURAL NETWORKS

Neural networks were used to calibrate an online ash analyzer at the Usibelli Coal Mine, Healy, Alaska, by relating the Americium and Cesium counts to the ash content. A total of 104 samples were collected from the mine, with 47 being from screened coal, and the rest being from unscreened coal. Each sample corresponded to 20 seconds of coal on the running conveyor belt. Neural network modeling used the quick stop training procedure. Therefore, the samples were split into training, calibration and prediction subsets. Special techniques, using genetic algorithms, were developed to representatively split the sample into the three subsets. Two separate approaches were tried. In one approach, the screened and unscreened coal was modeled separately. In another, a single model was developed for the entire dataset. No advantage was seen from modeling the two subsets separately. The neural network method performed very well on average but not individually, i.e. though each prediction was unreliable, the average of a few predictions was close to the true average. Thus, the method demonstrated that the analyzers were accurate at 2-3 minutes intervals (average of 6-9 samples), but not at 20 seconds (each prediction).
Date: December 5, 2003
Creator: Ganguli, Rajive; Walsh, Daniel E. & Yu, Shaohai
Object Type: Report
System: The UNT Digital Library
Phenomenological aspects of heterotic orbifold models at one loop (open access)

Phenomenological aspects of heterotic orbifold models at one loop

We provide a detailed study of the phenomenology of orbifold compactifications of the heterotic string within the context of supergravity effective theories. Our investigation focuses on those models where the soft Lagrangian is dominated by loop contributions to the various soft supersymmetry breaking parameters. Such models typically predict non-universal soft masses and are thus significantly different from minimal supergravity and other universal models. We consider the pattern of masses that are governed by these soft terms and investigate the implications of certain indirect constraints on supersymmetric models, such as flavor-changing neutral currents, the anomalous magnetic moment of the muon and the density of thermal relic neutralinos. These string-motivated models show novel behavior that interpolates between the phenomenology of unified supergravity models and models dominated by the superconformal anomaly.
Date: August 5, 2003
Creator: Birkedal-Hansen, A.; Binetruy, P.; Mambrini, Y. & Nelson, B.
Object Type: Report
System: The UNT Digital Library
Aperture studies for the AP2 anti-proton Line at Fermilab (open access)

Aperture studies for the AP2 anti-proton Line at Fermilab

The AP2 beamline transports anti-protons from the production target to the Debuncher ring. For many years the observed aperture has been smaller than that estimated from linear, on-energy optics. We have investigated possible reasons for the aperture restriction and have identified several possible sources, including residual vertical dispersion from alignment errors and chromatic effects due to very large chromatic lattice functions. We discuss the possible sources, suggest some remedies, and propose specific studies, where needed, to evaluate suspected problems.
Date: December 5, 2003
Creator: Reichel, Ina; Zisman, Michael & Placidi, Massimo
Object Type: Report
System: The UNT Digital Library
Manipulating and Visualizing Proteins (open access)

Manipulating and Visualizing Proteins

ProteinShop Gives Researchers a Hands-On Tool for Manipulating, Visualizing Protein Structures. The Human Genome Project and other biological research efforts are creating an avalanche of new data about the chemical makeup and genetic codes of living organisms. But in order to make sense of this raw data, researchers need software tools which let them explore and model data in a more intuitive fashion. With this in mind, researchers at Lawrence Berkeley National Laboratory and the University of California, Davis, have developed ProteinShop, a visualization and modeling program which allows researchers to manipulate protein structures with pinpoint control, guided in large part by their own biological and experimental instincts. Biologists have spent the last half century trying to unravel the ''protein folding problem,'' which refers to the way chains of amino acids physically fold themselves into three-dimensional proteins. This final shape, which resembles a crumpled ribbon or piece of origami, is what determines how the protein functions and translates genetic information. Understanding and modeling this geometrically complex formation is no easy matter. ProteinShop takes a given sequence of amino acids and uses visualization guides to help generate predictions about the secondary structures, identifying alpha helices and flat beta strands, and the …
Date: December 5, 2003
Creator: Simon, Horst D.
Object Type: Report
System: The UNT Digital Library
Quantum dynamics via Planck-scale-stepped action-carrying 'Graph Paths' (open access)

Quantum dynamics via Planck-scale-stepped action-carrying 'Graph Paths'

A divergence-free, parameter-free, path-based discrete-time quantum dynamics is designed to not only enlarge the achievements of general relativity and the standard particle model, by approximations at spacetime scales far above Planck scale while far below Hubble scale, but to allow tackling of hitherto inaccessible questions. ''Path space'' is larger than and precursor to Hilbert-space basis. The wave-function-propagating paths are action-carrying structured graphs-cubic and quartic structured vertices connected by structured ''fermionic'' or ''bosonic'' ''particle'' and ''nonparticle'' arcs. A Planck-scale path step determines the gravitational constant while controlling all graph structure. The basis of the theory's (zero-rest-mass) elementary-particle Hilbert space (which includes neither gravitons nor scalar bosons) resides in particle arcs. Nonparticle arcs within a path are responsible for energy and rest mass.
Date: May 5, 2003
Creator: Chew, Geoffrey F.
Object Type: Report
System: The UNT Digital Library
Mechanistic Study of Oxygen Atom Transfer Catalyzed by Rhenium Compounds (open access)

Mechanistic Study of Oxygen Atom Transfer Catalyzed by Rhenium Compounds

Two ionic and one neutral methyl(oxo)rhenium(V) compounds were synthesized and structurally characterized. They were compared in reactivity towards the ligands triphenylphosphane, pyridines, pyridine N-oxides. Assistance from Broensted bases was found on ligand displacement of ionic rhenium compounds as well as nucleophile assistance on oxidation of all compounds. From the kinetic data, crystal structures, and an analysis of the intermediates, a structural formula of PicH{sup +}3{sup -} and mechanisms of ligand displacement and oxidation were proposed.
Date: August 5, 2003
Creator: Shan, Xiaopeng
Object Type: Thesis or Dissertation
System: The UNT Digital Library
LARGE AREA FILTERED ARC DEPOSITION OF CARBON AND BORON BASED HARD COATINGS (open access)

LARGE AREA FILTERED ARC DEPOSITION OF CARBON AND BORON BASED HARD COATINGS

This document is a final report covering work performed under Contract No. DE-FG02-99ER82911 from the Department of Energy under a SBIR Phase II Program. Wear resistant, hard coatings can play a vital role in many engineering applications. The primary goal of this project was to develop coatings containing boron and carbon with hardness greater than 30 GPa and evaluate these coatings for machining applications. UES has developed a number of carbon and boron containing coatings with hardness in the range of 34 to 65 GPa using a combination of filtered cathodic arc and magnetron sputtering. The boron containing coatings were based on TiB2, TiBN, and TiBCN, while the carbon containing coatings ere TiC+C and hydrogen free diamond-like-carbon. Machining tests were performed with single and multilayer coated tools. The turning and milling tests were run at TechSolve Inc., under a subcontract at Ohio State University. Significant increases in tool lives were realized in end milling of H-13 die steel (8X) and titanium alloy (80%) using the TiBN coating. A multilayer TiBN/TiN performed the best in end-milling of highly abrasive Al-Si alloys. A 40% increase in life over the TiAlN benchmark coating was found. Further evaluations of these coatings with commercialization partners …
Date: December 5, 2003
Creator: Bhattacharya, Rabi S.
Object Type: Report
System: The UNT Digital Library
Mechanical Behavior and Fractography of 304 Stainless Steel with High Hydrogen Concentration (open access)

Mechanical Behavior and Fractography of 304 Stainless Steel with High Hydrogen Concentration

Hydrogen embrittlement of 304 stainless steel with different hydrogen concentrations has been investigated. An electrochemical technique was used to effectively charge the high level of hydrogen into 304 stainless steel in a short period of time. At 25 ppm of hydrogen, 304 stainless steel loses 10 percent of its original mechanical strength and 20 percent plasticity. Although the ductile feature dominates the fractography, the brittle crown area near the outer surface shows the intergranular rupture effected by hydrogen. At 60 ppm of hydrogen, 304 stainless steel loses 23 percent of its strength and 38 percent plasticity, where the brittle mode dominates the fracture of the materials. Experimental results show that hydrogen damage to the performance of 304 stainless steel is significant even at very low levels. The fractograph analysis indicates the high penetration ability of hydrogen in 304 stainless steel. This work also demonstrates the advantages of the electrochemical charging technique in the study of hydrogen embrittlement.
Date: February 5, 2003
Creator: Au, M.
Object Type: Article
System: The UNT Digital Library
High Frequency Electromagnetic Impedance Imaging for Vadose Zone and Groundwater Characterization (open access)

High Frequency Electromagnetic Impedance Imaging for Vadose Zone and Groundwater Characterization

A geophysical experiment is described for characterizing the clastic dike systems, which are ubiquitous within the vadose zone at the Hanford Nuclear Reservation. because the dikes possess a significant electrical contrast from the insulating host medium, we have applied controlled source audio magnetotelluric (CSAMT) measurements to map their geometric extent and to further clarify if the dike complex acts as a conduit for contaminant transport within the vadose zone. Because of cost and weak natural field signal levels, we employed controlled field sourcing using the STRATGEM acquisition system. Use of artificial fields often goes with the assumption that the data required in the far-field of the transmitter.
Date: June 5, 2003
Creator: Newman, Greory A.; Alumbaugh, David L.; Hoversten, Michael & Nichols, Edward
Object Type: Report
System: The UNT Digital Library
Edge Recycling and Heat Fluxes in L- and H-mode NSTX Plasmas (open access)

Edge Recycling and Heat Fluxes in L- and H-mode NSTX Plasmas

Introduction Edge characterization experiments have been conducted in NSTX to provide an initial survey of the edge particle and heat fluxes and their scaling with input power and electron density. The experiments also provided a database of conditions for the analyses of the NSTX global particle sources, core fueling, and divertor operating regimes.
Date: August 5, 2003
Creator: Soukhanovskii, V. A.; Maingi, R.; Raman, R.; Kugel, H.; LeBlanc, B.; Roquemore, A. L. et al.
Object Type: Report
System: The UNT Digital Library
Development of high Sensitivity Materials for Applications in Magneto-Mechanical Torque Sensor (open access)

Development of high Sensitivity Materials for Applications in Magneto-Mechanical Torque Sensor

The Matteucci effect, which mainly manifests itself as the change of magnetization of a material with torsional stress, is currently of great technological interest because of the search for magnetic torque sensors. Magnetic torque sensors are important to future improvements of automobiles and industrial robots. It is well known that the magnetic state of a material depends on both the external magnetic field and external stress which causes strain and change in magnetization of the material. The former phenomenon has been well understood in both theory and application. However, the magnetic state dependence of stress is not adequately understood and the experimental data is of limited extent. In this project, the Matteucci effect in iron, cobalt, nickel and permalloy rods has been documented when they were in magnetic remanence status along the axis and nickel ring when they were in remanence status along the circumference. The effect of annealing on the magnetomechanical effect in nickel and the temperature dependence of the magnetomechanical sensitivity has also been examined. Factors related to the sensitivity at equilibrium condition have been theoretically developed. it is found in the experiments that the mechanism of magnetic domain wall movement plays an important role rather than the …
Date: August 5, 2003
Creator: Shen, Yuping
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Generalized Portable SHMEM Library for High Performance Computing (open access)

Generalized Portable SHMEM Library for High Performance Computing

This dissertation describes the efforts to design and implement the Generalized Portable SHMEM library, GPSHMEM, as well as supplementary tools. There are two major components of the GPSHMEM project: the GPSHMEM library itself and the Fortran 77 source-to-source translator. The rest of this thesis is divided into two parts. Part I introduces the shared memory model and the distributed shared memory model. It explains the motivation behind GPSHMEM and presents its functionality and performance results. Part II is entirely devoted to the Fortran 77 translator call fgpp. The need for such a tool is demonstrated, functionality goals are stated, and the design issues are presented along with the development of the solutions.
Date: August 5, 2003
Creator: Parzyszek, Krzysztof
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Device Optimization and Transient Electroluminescence Studies of Organic light Emitting Devices (open access)

Device Optimization and Transient Electroluminescence Studies of Organic light Emitting Devices

Organic light emitting devices (OLEDs) are among the most promising for flat panel display technologies. They are light, bright, flexible, and cost effective. And while they are emerging in commercial product, their low power efficiency and long-term degradation are still challenging. The aim of this work was to investigate their device physics and improve their performance. Violet and blue OLEDs were studied. The devices were prepared by thermal vapor deposition in high vacuum. The combinatorial method was employed in device preparation. Both continuous wave and transient electroluminescence (EL) were studied. A new efficient and intense UV-violet light emitting device was developed. At a current density of 10 mA/cm{sup 2}, the optimal radiance R could reach 0.38 mW/cm{sup 2}, and the quantum efficiency was 1.25%. using the delayed EL technique, electron mobilities in DPVBi and CBP were determined to be {approx} 10{sup -5} cm{sup 2}/Vs and {approx} 10{sup -4} cm{sup 2}/Vs, respectively. Overshoot effects in the transient El of blue light emitting devices were also observed and studied. This effect was attributed to the charge accumulation at the organic/organic and organic/cathode interfaces.
Date: August 5, 2003
Creator: Zou, Lijuan
Object Type: Thesis or Dissertation
System: The UNT Digital Library