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Start Over Year 1999 Day 3rd

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Oral History Interview with Leslie W. Bray, Jr., March 3, 1999

Access: Use of this item is restricted to the UNT Community

Interview with Army Air Forces veteran Leslie W. Bray, Jr. The interview includes Bray's personal experiences about the China-Burma-India Theater during World War II, youth during the Great Depression, flight training, being designated as the commander of the 16th Combat Cargo Squadron, stationing at Sylhet, India as part of his assignment to the CBI Theater, supplying the British 14th Army in Burma, flying difficulties due to weather conditions, various transfers, and flying "The Hump." Bray also talks about his early aspirations to become an aviator, initial failures to pass the Air Forces physical examination, his assignment to Troop Carrier Command, flying C-47s with the 1st Troop Carrier Group, his appointment as assistant group operations officer for the 10th Troop Carrier Group, Air Force School of Applied Tactics, the training of replacement units at various Air Force installations, the deactivation of the 16th Combat Cargo Squadron, and his postwar Air Force career and retirement as a general officer.

Date: March 3, 1999

Creator: Alexander, William J. & Bray, Leslie W., Jr.

Object Type: Book

System: The UNT Digital Library

(open access)

Aqueous biphasic systems for metal separations : a microcalorimetric analysis of polymer/salt interactions.

Certain radionuclide ions (e.g., TcO{sub 4}{sup 16}) exhibit unusually strong Affinities toward the polymer-rich phase in aqueous biphase systems generated by combinations of salt solutions with polymers such as poly(ethylene glycol) (PEG) and poly(propylene glycol) (PPG). Thus, aqueous polymer phases could potentially be used to selectively extract these ions during pretreatment of radioactive tank wastes at Hanford. To help develop a fundamental understanding of the interactions between various ions and polymers in aqueous solution, interaction enthalpies between sodium perrhenate and a random copolymer of PEG and PPG (UCON-50) were measured by microcalorimetric titration. An entropy compensation effect was observed in this system in which changes in enthalpic interactions were balanced by entropy changes such that the interaction free energy remained constant and approximately equal to zero.

Date: May 3, 1999

Creator: Chaiko, D. J.; Hatton, T. A. & Zaslavsky, B.

Object Type: Article

System: The UNT Digital Library

(open access)

Characteristics of ICF Relevant Hohlraums Driven by X-Rays from a Z-Pinch

Radiation environments characteristic of those encountered during the low-temperature foot pulse and subsequent higher-temperature early-step pulses (without the foot pulse) required for indirect-drive ICF ignition on the National ignition Facility have been produced in hohlraums driven by x-rays from a z-pinch. These environments provide a platform to better understand the dynamics of full-scale NIF hohlraums, ablator material, and capsules prior to NIF completion. Radiation temperature, plasma fill, and wall motion of these hohlraums are discussed.

Date: November 3, 1999

Creator: Bowers, R. L.; Chandler, Gordon A.; Hebron, David E.; Leeper, Ramon J.; Matuska, W.; Mock, Raymond Cecil et al.

Object Type: Article

System: The UNT Digital Library

(open access)

Scale up issues involved with the ceramic waste form : ceramic-container interactions and ceramic cracking quantification.

Argonne National Laboratory is developing a process for the conditioning of spent nuclear fuel to prepare the material for final disposal. Two waste streams will result from the treatment process, a stainless steel based form and a ceramic based form. The ceramic waste form will be enclosed in a stainless steel container. In order to assess the performance of the ceramic waste form in a repository two factors must be examined, the surface area increases caused by waste form cracking and any ceramic/canister interactions that may release toxic material. The results indicate that the surface area increases are less than the High Level Waste glass and any toxic releases are below regulatory limits.

Date: May 3, 1999

Creator: Bateman, K. J.; DiSanto, T.; Goff, K. M.; Johnson, S. G.; O'Holleran, T. & Riley, W. P., Jr.

Object Type: Article

System: The UNT Digital Library

(open access)

An Improved Direct Measurement of Leptonic Coupling Asymmetries with Polarized Z{sup 0}'s

We report new direct measurements of the Z{sup 0}-lepton coupling asymmetry parameters A{sub e}, A{sub {mu}} and A{sub r}, with polarized Z{sup 0}'s collected by the SLD detector at the SLAC Linear Collider. The parameters are extracted from the measurement of the left-right-forward-backward asymmetries for each lepton species. The 1996, 1997 and 1998 SLD runs are included in this analysis and combined with published data from the 1993-95 runs. Preliminary results are A{sub e} = 0.1558 {+-} 0.0064, A{sub {mu}} = 0.137 {+-} 0.016 and A{sub {tau}} = 0.142 {+-} 0.016. If lepton universality is assumed, a combined asymmetry parameter A{sub l} = 0.1523 {+-} 0.0057 results. This translates into an effective weak mixing angle sin{sup 2} {theta}{sub W}{sup eff} = 0.23085 {+-} 0.00073 at the Z{sup 0} resonance.

Date: August 3, 1999

Creator: Abe, Toshinori

Object Type: Report

System: The UNT Digital Library

(open access)

Shock-recovery experiments of sandstone under dry and water-saturated conditions

Shock-recovery experiments have been performed on Berea Sandstone under dry and water-saturated conditions using a single-stage light-gas gun. Stress levels in the range between 3.1 and 9.8 GPa were achieved by impacting projectiles in a recovery fixture. The microstructural damage of the shocked samples were analyzed with scanning electron microscopy (SEM), laser particle analysis and X-ray computed micro tomography (XCMT). The dry samples show strongly and irregularly fragmented quartz grains with an considerably reduced porosity. In contrast, the water-saturated specimens have less grain damage and higher porosity. The water in the pores distributes the stresses which reduce the contact force between the grains during the shock compression. The dynamic fragmentation of the grain-grain interactions was modeled by explicitly treating the grain-pore structure using the Smooth Particle Hydrodynamic (SPH) computational method. This is a continuum Lagrangian gridless approach that features particles.

Date: September 3, 1999

Creator: Hiltl, M; Nellis, W J; Swift, R P; Hagelberg, C R & Carney, T C

Object Type: Article

System: The UNT Digital Library

(open access)

West Hackberry Tertiary Project

The West Hackberry Tertiary Project is a field test of the concept that air injection can generate tertiary oil recovery through the Double Displacement Process. The Double Displacement Process is the gas displacement of a water invaded oil column for the purpose of recovering tertiary oil through gravity drainage. The novel aspect of this project is the use of air as the injection fluid. In Gulf Coast oil reservoirs with pronounced bed dip, reservoir performance has shown that gravity drainage recoveries average 80% to 90% of the original oil in place while water drive recoveries average 50% to 60% of the original oil in place. The target for tertiary oil recovery with the Double Displacement Process is the incremental oil between the 50% to 60% water drive recoveries and the 80% to 90% gravity drainage recoveries. The use of air injection in this process combines the benefits of air's low cost and universal accessibility with the potential for improved oil recovery resulting from spontaneous in situ combustion. If successful, this project will demonstrate that utilizing air injection in the Double Displacement Process will result in an economically viable tertiary process in many Gulf Coast oil reservoirs where other tertiary processes …

Date: November 3, 1999

Creator: Gillham, Travis & Yannimaras, Demetrios

Object Type: Report

System: The UNT Digital Library

(open access)

Faulty assumptions for repository requirements

Long term performance requirements for a geologic repository for spent nuclear fuel and high-level waste are based on assumptions concerning water use and subsequent deaths from cancer due to ingesting water contaminated with radio isotopes ten thousand years in the future. This paper argues that the assumptions underlying these requirements are faulty for a number of reasons. First, in light of the inevitable technological progress, including efficient desalination of water, over the next ten thousand years, it is inconceivable that a future society would drill for water near a repository. Second, even today we would not use water without testing its purity. Third, today many types of cancer are curable, and with the rapid progress in medical technology in general, and the prevention and treatment of cancer in particular, it is improbable that cancer caused by ingesting contaminated water will be a sign&ant killer in the far future. This paper reviews the performance requirements for geological repositories and comments on the difficulties in proving compliance in the face of inherent uncertainties. The already tiny long-term risk posed by a geologic repository is presented and contrasted with contemporary every day risks. A number of examples of technological progress, including cancer treatments, …

Date: June 3, 1999

Creator: Sutcliffe, W G

Object Type: Article

System: The UNT Digital Library

(open access)

Summary of experimental electroweak physics.

Progress continues on many fronts of experimental testing of electroweak symmetry breaking. Updates were presented on LEP, SLC, Brookhaven g-2 ring, Tevatron Collider, HERA, CESR and Tevatron neutrino experiments. Perhaps most exciting is the Higgs search at LEP2, complementing the indirect constraints. However, the standard model with one Higgs doublet remains viable.

Date: May 3, 1999

Creator: Nodulman, L.

Object Type: Article

System: The UNT Digital Library

(open access)

Formalizing the concept of sound.

The notion of formalized music implies that a musical composition can be described in mathematical terms. In this article we explore some formal aspects of music and propose a framework for an abstract approach.

Date: August 3, 1999

Creator: Kaper, H. G. & Tipei, S.

Object Type: Article

System: The UNT Digital Library

(open access)

Status of the new muon (g - 2) experiment.

The new muon (g - 2) experiment is now fully operational The goal of the experiment is to obtain a relative error on (g - 2) of {+-}O.35 ppm to measure the electroweak contribution for the first time, and to observe, or place stringent limits on physics beyond the standard model which can contribute to (g - 2). A brief status report is presented.

Date: May 3, 1999

Creator: Carey, R. M.; Earle, W.; Efstathiadis, E.; Hare, M. F.; Collaboration, MUON (g - 2); Nodulman, L. et al.

Object Type: Article

System: The UNT Digital Library

(open access)

Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

The eighteen 10-acre infill wells which were drilled as part of the field demonstration portion of the project are all currently in service with no operational problems. These wells consist of fourteen producing wells and four injection wells. The producing wells are currently producing a total of approximately 376 bopd, down from a peak rate of 900 bopd. The four injection wells are currently injecting a total of 140 bwipd. Unit production is currently averaging approximately 2,600 bopd, 12,000 bwpd and 18,000 bwipd.

Date: November 3, 1999

Creator: Company, Fina Oil and Chemical

Object Type: Report

System: The UNT Digital Library

(open access)

Cost-Effective Remediation of Depleted Uranium (DU) at Environmental Restoration Sites

Numerous sites in the United States and around the world are contaminated with depleted uranium (DU) in various forms. A prevalent form is fragmented DU originating from various scientific tests involving high explosives and DU during weapon-development programs, at firing practice ranges, or in war theaters where DU was used in armor-piercing projectiles. The contamination at these sites is typically very heterogeneous, with discrete, visually identifiable DU fragments mixed with native soil. The bulk-averaged DU activity is quite low, whereas DU fragments, which are distinct from the soil matrix, have much higher specific activity. DU is best known as a dark metal that is nearly twice as dense as lead, but DU in the environment readily weathers (oxidizes) to a distinctive bright yellow color that is quite visible. While the specific activity (amount of radioactivity per mass of soil) of DU is relatively low and presents only a minor radiological hazard, the fact that DU is radioactive and visually identifiable makes it desirable to remove the DU ''contamination'' from the environment. The typical approach to conducting this DU remediation is to use radiation-detection instruments to identify the contaminant and then to separate it from the adjacent soil, packaging it for …

Date: November 3, 1999

Creator: Miller, Mark; Galloway, Robert B.; Vanderpoel, Glenn; Johnson, E. D.; Copland, John & Salazar, Michael

Object Type: Article

System: The UNT Digital Library

(open access)

Toward a fourth-generation light source.

Historically, x-ray research has been propelled by the existence of urgent and compelling scientific questions and the push of powerful and exquisite source technology. These two factors have gone hand in hand since Rontgen discovered x-rays. Here we review the progress being made with existing third-generation synchrotron-radiation light sources and the prospects for a fourth-generation light source with dramatically improved laser-like beam characteristics. The central technology for high-brilliance x-ray beams is the x-ray undulator, a series of alternating-pole magnets situated above and below the particle beam. When the particle beam is oscillated by the alternating magnetic fields, a set of. interacting and interfering wave fronts is produced, which leads to an x-ray beam with extraordinary properties. Third-generation sources of light in the hard x-ray range have been constructed at three principal facilities: the European Synchrotrons Radiation Facility (ESRF) in France; the Super Photon Ring 8-GeV (or Spring-8) in Japan; and the Advanced Photon Source (APS) in the US. Undulator technology is also used on a number of low-energy machines for radiation in the ultraviolet and soft x-ray regimes. At the APS, these devices exceed all of our original expectations for beam brilliance, tunability, spectral range, and operational flexibility. Shown in …

Date: May 3, 1999

Creator: Moncton, D. E.

Object Type: Article

System: The UNT Digital Library

(open access)

Stiffness and Strength Properties for Basic Sandwich Material Core Types

Three basic core material types for sandwich structure applications are studied. The three two-dimensional pattern types are: honeycomb, triangular cells, and a new configuration involving star type cells. The specific critical properties of stiffness and strength type are identified and studied, both theoretically and experimentally.

Date: August 3, 1999

Creator: Kim, B. & Christensen, R. M.

Object Type: Article

System: The UNT Digital Library

(open access)

Improved Oil Recovery in Fluvial Dominated Deltaic Reservoirs of Kansas - Near-Term

The objective of this project is to address waterflood problems of the type found in Morrow sandstone reservoirs in southwestern Kansas and in Cherokee Group reservoirs in southeastern Kansas. Two demonstration sites operated by different independent oil operators are involved in this project. The Stewart Field is located in Finney County, Kansas and is operated by PetroSantander, Inc. Te Nelson Lease is located in Allen County, Kansas, in the N.E. Savonburg Field and is operated by James E. Russell Petroleum, Inc. General topics to be addressed are (1) reservoir management and performance evaluation, (2) waterflood optimization, and (3) the demonstration of recovery processes involving off-the-shelf technologies which can be used to enhance waterflood recovery, increase reserves, and reduce the abandonment rate of these reservoir types. In the Stewart Project, the reservoir management portion of the project conducted during Budget Period 1 involved performance evaluation. This included (1) reservoir characterization and the development of a reservoir database, (2) volumetric analysis to evaluate production performance, (3) reservoir modeling, (4) laboratory work, (5) identification of operational problems, (6) identification of unrecovered mobile oil and estimation of recovery factors, and (7) Identification of the most efficient and economical recovery process. To accomplish these objectives …

Date: November 3, 1999

Creator: Green, Don W.; McCune, A. D.; Michnick, M.; Reynolds, R.; Walton, A.; Watney, L. et al.

Object Type: Report

System: The UNT Digital Library

(open access)

ITER structural design criteria and their extension to advanced fusion reactor blankets.

Application of the new low-temperature-design rules of the ITER Structural Design Criteria (ISDC) is illustrated by considering copper alloys that, according to recent data, are particularly prone to irradiation embrittlement at relatively low fluences at certain temperatures, Allowable stresses are derived and the impact of the embrittlement on allowable surface heat flux of a simple first-wall/limiter design is demonstrated. High-temperature-design rules of ISDC are applied to EVOLVE (Evaporation Of Lithium and Vapor Extraction), a blanket design concept currently being investigated under the U.S. APEX (Advanced Power Extraction) program. One version of this concept envisions the use of a series of parallel tungsten tubes (first-wall) that are cooled internally by lithium vapor, typically. at 1200 C. A single tungsten first-wall tube is considered for thermal and stress analyses by finite-element method.

Date: September 3, 1999

Creator: Kalnin, G. & Majumdar, S.

Object Type: Article

System: The UNT Digital Library

(open access)

Sandia National Laboratories: The First Fifty Years

On Nov. 1, 1999, Sandia National Laboratories celebrates its 50th birthday. Although Sandia has its roots in the World War II-era Manhattan Project, Sandia began operating as a separate nuclear weapons engineering laboratory under the management of AT&T on Nov. 1, 1949. Today the lab employs more than 7,000 people at its two sites in Albuquerque and Livermore, California, and has research and development missions in national security, energy and environmental technologies, and U.S. economic competitiveness. Lockheed Martin Corporation operates Sandia for the US. Department of Energy.

Date: November 3, 1999

Creator: MORA,CARL J.

Object Type: Article

System: The UNT Digital Library

(open access)

Portable data acquisition system

Lawrence Livermore National Laboratory (LLNL) has developed a Portable Data Acquisition (DAQ) System that is basically a laboratory-scale of Program Logic Control (PLC). This DAQ system can obtain signals from numerous sensors (e.g., pH, level, pressure, flow meters), open and close valves, and turn on and off pumps. The data can then be saved on a spreadsheet or displayed as a graph/indicator in real-time on a computer screen. The whole DAQ system was designed to be portable so that it could sit on a bench top during laboratory-scale treatability studies, or moved out into the field during larger studies. This DAQ system is also fairly simple to use. All that is required is some working knowledge of LabVIEW 4.1, and how to properly wire the process equipment. The DAQ system has been used during treatability studies on cesium precipitation, controlled hydrolysis of water- reactive wastes, and other waste treatment studies that enable LLNL to comply with the Federal Facility Compliance Act (FFCAct). Improved data acquisition allows the study to be better monitored, and therefore better controlled, and can be used to determine the results of the treatment study more effectively. This also contributes to the design of larger treatment processes.

Date: May 3, 1999

Creator: Bowers, J & Rogers, H

Object Type: Article

System: The UNT Digital Library

(open access)

Critical comparison of 3D imaging approaches

Currently three imaging spectrometer architectures, tunable filter, dispersive, and Fourier transform, are viable for imaging the universe in three dimensions. There are domains of greatest utility for each of these architectures. The optimum choice among the various alternative architectures is dependent on the nature of the desired observations, the maturity of the relevant technology, and the character of the backgrounds. The domain appropriate for each of the alternatives is delineated; both for instruments having ideal performance as well as for instrumentation based on currently available technology. The environment and science objectives for the Next Generation Space Telescope will be used as a specific representative case to provide a basis for comparison of the various alternatives.

Date: June 3, 1999

Creator: Bennett, C L

Object Type: Article

System: The UNT Digital Library

(open access)

InGaAsN/AlGaAs Pnp Heterojunction Bipolar Transistor

The authors have demonstrated a functional Pnp heterojunction bipolar transistor (HBT) using InGaAsN. The metalorganic vapor phase epitaxy (MOCVD) grown Al{sub 0.3}Ga{sub 0.7}As/In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01} HBT takes advantage of the narrower bandgap energy (E{sub g} = 1.25eV) of In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01}, which is lattice matched to GaAs. Compared with the Al{sub 0.3}Ga{sub 0.7}As/GaAs material system, the Al{sub 0.3}Ga{sub 0.7}As/In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01} material system has a larger conduction band offset, while the valence band offset remains comparable. This characteristic band alignment is very suitable for Pnp HBT applications. The device's peak current gain is 23 and it has a turn on voltage of 0.77V, which is 0.25V lower than in a comparable Pnp Al{sub 0.3}Ga{sub 0.7}As/GaAs HBT.

Date: November 3, 1999

Creator: Baca, Albert G.; Chang, Ping-Chih; Hou, H. Q.; Laroche, J. R.; Li, N. Y.; Ren, F. et al.

Object Type: Article

System: The UNT Digital Library

(open access)

Shock Compressed Solids on the Nova Laser

Experiments are being developed to shock compress metal foils in the solid state to study the material strength under high compression. The x-ray drive has been characterized and hydrodynamics experiments performed to study growth of the Rayleigh-Taylor (RT) instability in Al foils at a peak pressure of about 1.8 Mbar. Pre-imposed modulations with an initial wavelength of lo-50 pm, and amplitude of 0.5 pm show growth. Variation in the growth factors may be a result of shot-shot variation in preheating of the Al sample due to emission from the plasma in the hohlraum target

Date: August 3, 1999

Creator: Colvin, J. D.; Gold, D. M.; Kalantar, D. H.; Mikaelian, K. O.; Remington, B. A.; Weber, S. V. et al.

Object Type: Article

System: The UNT Digital Library