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Alumni J-TAC, Spring 1994 (open access)

Alumni J-TAC, Spring 1994

Alumni magazine of Tarleton State University providing information on events at the school and news about university students, staff, and alumni.
Date: Spring 1994
Creator: Tarleton State University
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Sensor for measuring the atomic fraction in highly dissociated hydrogen (open access)

Sensor for measuring the atomic fraction in highly dissociated hydrogen

Atomic hydrogen is a very important constituent for processes ranging from cleaning oxide from GaAs and annealing amorphous silicon to the deposition of diamond. Because the usual techniques for measuring atomic fraction are either expensive and cumbersome to use, or unsuitable for application to highly dissociated hydrogen, a specially designed sensor was developed. Sensor design is based on a diffusion tube with noncatalytic walls, having one end open to the atom source and a catalytic closure at the other end. The sensor is simple and inexpensive to fabricate, and determining atom density is straightforward. Sensor design also inhibits thermal runaway, which occurs when atom density is high enough to impart enough recombination energy to the non-catalytic surface to substantially raise its temperature. While recombination coefficients for such surfaces are very low near room temperature, they increase nearly exponentially with temperature unless actively cooled. With the use of a straightforward calibration scheme to determine the variation in species fraction along the diffusion tube, the atomic fraction at the tube opening is determined. Design strategy, implementation considerations, and calibration method are presented. In addition, data obtained from an atomic hydrogen source are compared to relevant published data.
Date: December 31, 1994
Creator: Gardner, W.L.
Object Type: Report
System: The UNT Digital Library
Alumni J-TAC, Homecoming 1994 (open access)

Alumni J-TAC, Homecoming 1994

Homecoming edition of the Tarleton State University alumni magazine describing related events and other news about university students, staff, and alumni.
Date: Autumn 1994
Creator: Tarleton State University
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
The J-TAC (Stephenville, Tex.), Vol. 148, No. 3, Ed. 1 Thursday, September 22, 1994 (open access)

The J-TAC (Stephenville, Tex.), Vol. 148, No. 3, Ed. 1 Thursday, September 22, 1994

Weekly student newspaper from Tarleton State University in Stephenville, Texas that includes local, state and campus news along with advertising.
Date: September 22, 1994
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Micromechanical modeling of damage and inelasticity of composite materials in macroscopic structural analysis (open access)

Micromechanical modeling of damage and inelasticity of composite materials in macroscopic structural analysis

The method of cells has been extended to include damage or debonding between all adjacent subcells using a finite element formulation for the original cells assembly. Damage is implemented by placing a nonlinear three-dimensional spring between adjacent subcells. With this arrangement the damage is inherently anisotropic. The ``nonlinear substructure`` cells finite element model is incorporated as a user defined material routine in a general purpose finite element code. The primary motivation for casting the method of cells as a finite element assemblage is to provide a composite constitutive model that facilitates the incorporation of various constituent material models, as well as any level of detail desired in the microstructure geometry. At present, the constituent material models may be anisotropic elastic or isotropic viscoelastic-plastic, while damage evolution is based on the macroscopic strain. The capability of the model is demonstrated through analyses of some simple structures loaded to failure.
Date: December 1, 1994
Creator: Macek, R. W.; Gardner, J. P. & Hackett, R. M.
Object Type: Article
System: The UNT Digital Library
Three-dimensional radiation transport hydrodynamics (open access)

Three-dimensional radiation transport hydrodynamics

None
Date: July 1, 1994
Creator: Fyfc, D. E.; Dahlburg, J. P.; Gardner, J. H. & Haan, S. W.
Object Type: Report
System: The UNT Digital Library
Optical assessment of large marine particles: development of an imaging and analysis sytem for quantifying large particle distributions and fluxes. Annual report, 1992-1993 (open access)

Optical assessment of large marine particles: development of an imaging and analysis sytem for quantifying large particle distributions and fluxes. Annual report, 1992-1993

The central goal of DOE`s Ocean Margin Program (OMP) is to determine whether continental shelves are quantitatively significant in removing carbon dioxide from the atmosphere and isolating it via burial in sediments or exporting it to the open ocean (Program Announcement, 1991). A major component of the OMP will be to measure carbon flux on the shelf and across the shelf to the slope and open ocean. We are developing a video and optical instrument package (LAPS: Large Aggregate Profiling System) and the analytical techniques to precisely measure a wide spectrum of the large aggregate population of particles in the shelf/slope environment. This particle population, encompassing the ``marine snow`` size particles (diameters > 0.5 mm), is thought to be the major pathway of material flux in the ocean (McCave, 1975; Asper, 1987; Walsh and Gardner, 1992). Our goal is to use aggregate abundance and size spectrum data along with the CTD, beam attenuation and fluorescence data collected with our instrument package to collect data rapidly, repeatedly and accurately such that it is both linkable to carbon flux and usable in biophysical models. Additionally, measurements of particle flux will be made with sediment traps deployed on the continental slope in conjunction …
Date: May 1, 1994
Creator: Walsh, I. D. & Gardner, W. D.
Object Type: Report
System: The UNT Digital Library
Scientific drilling in the Valles caldera magma-hydrothermal system, New Mexico (open access)

Scientific drilling in the Valles caldera magma-hydrothermal system, New Mexico

None
Date: April 1, 1994
Creator: Goff, F.; Gardner, J. N.; Heiken, G. & Hulen, J. B.
Object Type: Report
System: The UNT Digital Library
Analysis of resonance-driving imperfections in the AGS Booster (open access)

Analysis of resonance-driving imperfections in the AGS Booster

At the design intensity of 1.5 {times} 10{sup 13} ppp, the space charge tune shift in the AGS Booster at injection has been estimated to be about 0.35. The beam tunes are therefore spread over many lower order resonance lines and the associated stopbands must be corrected in order to minimize the amplitude growth due to resonance excitation. This requires proper compensation of the resonance-driving harmonics which result from random magnetic field errors. The observation and correction of second and third order resonance stopbands in the AGS Booster is reviewed, and an analysis of magnetic field imperfections based on the required corrections is given.
Date: August 1, 1994
Creator: Gardner, C.; Shoji, Y.; Danby, G.; Glenn, J. W.; Jackson, G. J.; Soukas, A. et al.
Object Type: Article
System: The UNT Digital Library
Contamination surveys for release of material (open access)

Contamination surveys for release of material

This report describes, and presents the technical basis for, a methodology for performing instrument surveys to release material from radiological control, including release to controlled areas and release from radiological control. The methodology is based on a fast scan survey, a large-area wipe survey, and a series of statistical, fixed measurements. The methodology meets the requirements of the US Department of Energy Radiological Control Manual (RadCon Manual) (DOE 1994) and DOE Order 5400.5 (DOE 1990) for release of material in less time than is required by a conventional scan survey. Implementation of the proposed methodology with a confidence interval of 67% will meet the material release requirements. The material evaluation process will allow material that has not been exposed to contamination to be released from radiological control without a survey. For potential radioactive contaminants that are not reserved in DOE Order 5400.5, the methodology will allow material to be released from radiological control. For other radionuclides, with the exception of some difficult-to-detect radionuclides, material may be released for controlled use. Compared with current techniques, the proposed methodology will reduce the amount of time required to perform surveys.
Date: May 1, 1994
Creator: Durham, J. S.; Johnson, M. L. & Gardner, D. L.
Object Type: Report
System: The UNT Digital Library
Lower active metals loading for hydrotreating catalysts (open access)

Lower active metals loading for hydrotreating catalysts

Hydrous Metal Oxides (HMOs) are chemically synthesized materials which contain a homogeneous distribution of ion exchangeable alkali cations that provide charge compensation to the metal-oxygen framework. Both the presence of these alkali cations and the resulting high cation exchange capacities (4-5 meq/g) clearly set these HMO materials apart from conventional precipitated hydrous oxides. For catalyst applications, the HMO material serves as an ion exchangeable support which facilitates the uniform incorporation of catalyst precursor species. Following catalyst precursor incorporation, an activation step is required to convert the catalyst precursor to the desired active phase. Considerable process development activities at Sandia National Laboratories related to HMO materials have resulted in bulk silica-doped hydrous titanium oxide (HTO:Si)-supported NiMo catalysts that are more active in model compound reactions than commercial NiMo catalysts. These reactions, e.g. pyrene hydrogenation, simulate direct coal liquefaction. However, extension of this process to produce NiMo/HTO:Si catalyst coatings on commercial supports is of interest for liquefaction applications since overall catalyst cost can be reduced and bulk HTO:Si mechanical limitations can be circumvented. In the present effort, NiMo/HTO:Si has been evaluated for hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) of coal derived liquids. NiMo/HTO:Si catalysts have been evaluated in both bulk (unsupported) form and …
Date: September 1, 1994
Creator: Lott, S. E.; Gardner, T. J.; McLaughlin, L. I. & Oelfke, J. B.
Object Type: Article
System: The UNT Digital Library
Comparison of nickel molybdenum hydrous metal oxides with commercial catalysts for HDS/HDN of coal liquids (open access)

Comparison of nickel molybdenum hydrous metal oxides with commercial catalysts for HDS/HDN of coal liquids

Improved efficiency in direct coal liquefaction processes can be obtained by developing catalysts with better activity, selectivity, and life. In previous exploratory research at Sandia National Laboratories, catalysts prepared via hydrous metal oxide (HMO) ion exchangers have been shown to have potential for application to a number of reactions associated with the conversion of coal to liquid fuels. In the present effort, one member of this class of catalysts, hydrous titanium oxide (HTO), has been used to develop catalysts for hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) of coal liquids. For HYD of pyrone, unsupported NiMoHTO catalysts performed better than commercial benchmark catalysts on either a catalyst weight or active metals basis. In a side-by-side comparison of supported NiMoHTO catalysts with commercial counterparts, the supported NiMoHTO catalysts outperformed the Shell 324 and Amocat 1C catalysts for HYD of pyrene. For HDS/HDN of coal liquids, the supported and bulk forms of the NiMoHTO catalysts equaled the performance of the commercial catalysts at 500, 1000, and 1500 psig while containing less active metals. Possible reasons for the high activity of the NiMoHTO catalysts are a high dispersion of the active MoS{sub 2} phase and a high acidity of the bulk NiMoHTO.
Date: June 1, 1994
Creator: Lott, S. E.; Gardner, T. J.; McLaughlin, L. I. & Oelfke, J. B.
Object Type: Article
System: The UNT Digital Library
Development of a process control sensor for the glass industry. Phase 2: Prototype design, development and demonstration (open access)

Development of a process control sensor for the glass industry. Phase 2: Prototype design, development and demonstration

This report describes an advanced multichannel, on-line optical system for the non-contact measurement of forehearth glass melt temperatures at depth. The analyzer employs multiple narrow infrared (IR) band measurements of glass radiation to reconstruct the glass temperature profiles at depth. The TAS replaces expensive Tri-plex thermocouples, which frequently have service lives as short as 6 months to 1 years. By using passive non-contact sensor heads and fiber optic cables, temperature sensitive electronic components can be located at a safe distance from the hostile process environment. This provides significantly better reliability of the vulnerable electro-optic components and ready access for maintenance.
Date: June 1, 1994
Creator: Gardner, M.; Candee, A. & Koppang, R.
Object Type: Report
System: The UNT Digital Library
Geohydrologic study of the Michigan Basin for the applicability of Jack W. McIntyre`s patented process for simultaneous gas recovery and water disposal in production wells (open access)

Geohydrologic study of the Michigan Basin for the applicability of Jack W. McIntyre`s patented process for simultaneous gas recovery and water disposal in production wells

Geraghty & Miller, Inc. of Midland, Texas conducted a geohydrologic study of the Michigan Basin to evaluate the applicability of Jack McIntyre`s patented process for gas recovery and water disposal in production wells. A review of available publications was conducted to identify, (1) natural gas reservoirs which generate large quantities of gas and water, and (2) underground injection zones for produced water. Research efforts were focused on unconventional natural gas formations. The Antrim Shale is a Devonian gas shale which produces gas and large quantities of water. Total 1992 production from 2,626 wells was 74,209,916 Mcf of gas and 25,795,334 bbl of water. The Middle Devonian Dundee Limestone is a major injection zone for produced water. ``Waterless completion`` wells have been completed in the Antrim Shale for gas recovery and in the Dundee Limestone for water disposal. Jack McIntyre`s patented process has potential application for the recovery of gas from the Antrim Shale and simultaneous injection of produced water into the Dundee Limestone.
Date: March 1, 1994
Creator: Maryn, S.
Object Type: Report
System: The UNT Digital Library
High intensity proton operation at the Brookhaven AGS accelerator complex (open access)

High intensity proton operation at the Brookhaven AGS accelerator complex

With the completion of the AGS rf upgrade, and the implementation of a transition {open_quotes}jump{close_quotes}, all of accelerator systems were in place in 1994 to allow acceleration of the proton intensity available from the AGS Booster injector to AGS extraction energy and delivery to the high energy users. Beam commissioning results with these new systems are presented. Progress in identifying and overcoming other obstacles to higher intensity are given. These include a careful exploration of the stopband strengths present on the AGS injection magnetic porch, and implementation of the AGS single bunch transverse dampers throughout the acceleration cycle.
Date: August 1, 1994
Creator: Ahrens, L. A.; Blaskiewicz, M.; Bleser, E.; Brennan, J. M.; Gardner, C.; Glenn, J. W. et al.
Object Type: Article
System: The UNT Digital Library
Performance issues for engineering analysis on MIMD parallel computers (open access)

Performance issues for engineering analysis on MIMD parallel computers

We discuss how engineering analysts can obtain greater computational resolution in a more timely manner from applications codes running on MIMD parallel computers. Both processor speed and memory capacity are important to achieving better performance than a serial vector supercomputer. To obtain good performance, a parallel applications code must be scalable. In addition, the aspect ratios of the subdomains in the decomposition of the simulation domain onto the parallel computer should be of order 1. We demonstrate these conclusions using simulations conducted with the PCTH shock wave physics code running on a Cray Y-MP, a 1024-node nCUBE 2, and an 1840-node Paragon.
Date: August 1, 1994
Creator: Fang, H. E.; Vaughan, C. T. & Gardner, D. R.
Object Type: Article
System: The UNT Digital Library
Summary of the working group on tests of QCD (open access)

Summary of the working group on tests of QCD

The working group discussed several topics related to charm production that can provide important input for our understanding of QCD. It was recognized that studies of both open and hidden charm in a high-statistics experiment will be essential in order to understand the production mechanisms. Nuclear effects were also discussed and a connection was made to similar effects observed in other reactions.
Date: September 1, 1994
Creator: Papavassiliou, V.
Object Type: Article
System: The UNT Digital Library
Groundwater maps of the Hanford Site, June 1994 (open access)

Groundwater maps of the Hanford Site, June 1994

This report is a continuation of reports (Kasza et al., 1994) that document the configuration of the uppermost unconfined aquifer beneath the Hanford Site. This series presents the results of the semiannual water level measurement program and the water table maps generated from these measurements. The reports document the changes in the groundwater level at the Hanford Site during the transition from nuclear material production to environmental restoration and remediation. In addition, these reports provide water level data to support the various site characterization and ground water monitoring programs currently in progress on the Hanford Site. This report highlights the three major operations areas (the 100, 200, and 300/1100 Areas) where wastes were discharged to the soil. Each area includes a summary discussion of the data, a well index map, and a contoured map of the water table surface.
Date: December 1, 1994
Creator: Serkowski, J. A.; Jordan, W. A. & Hartman, M. J.
Object Type: Report
System: The UNT Digital Library
Occupational dose reduction at Department of Energy contractor facilities: Bibliography of selected readings in radiation protection and ALARA; Volume 5 (open access)

Occupational dose reduction at Department of Energy contractor facilities: Bibliography of selected readings in radiation protection and ALARA; Volume 5

Promoting the exchange of information related to implementation of the As Low as Reasonably Achievable (ALARA) philosophy is a continuing objective for the Department of Energy (DOE). This report was prepared by the Brookhaven National Laboratory (BNL) ALARA Center for the DOE Office of Health. It contains the fifth in a series of bibliographies on dose reduction at DOE facilities. The BNL ALARA Center was originally established in 1983 under the sponsorship of the Nuclear Regulatory Commission to monitor dose-reduction research and ALARA activities at nuclear power plants. This effort was expanded in 1988 by the DOE`s Office of Environment, Safety and Health, to include DOE nuclear facilities. This bibliography contains abstracts relating to various aspects of ALARA program implementation and dose-reduction activities, with a specific focus on DOE facilities. Abstracts included in this bibliography were selected from proceedings of technical meetings, journals, research reports, searches of the DOE Energy, Science and Technology Database (in general, the citation and abstract information is presented as obtained from this database), and reprints of published articles provided by the authors. Facility types and activities covered in the scope of this report include: radioactive waste, uranium enrichment, fuel fabrication, spent fuel storage and reprocessing, …
Date: January 1, 1994
Creator: Dionne, B. J.; Sullivan, S. G. & Baum, J. W.
Object Type: Report
System: The UNT Digital Library
Prototype explosives-detection system based on nuclear-resonance absorption in nitrogen (open access)

Prototype explosives-detection system based on nuclear-resonance absorption in nitrogen

A prototype explosives-detection system (EDS) that was developed for experimental evaluation of a nuclear-resonance absorption technique is described. The major subsystems are a proton accelerator and beam transport, high-temperature proton target, an airline-luggage tomographic inspection station, and an image-processing/detection-alarm subsystem. The detection system performance, based on a limited experimental test, is reported.
Date: June 1, 1994
Creator: Morgado, R. E.; Arnone, G.; Cappiello, C. C.; Gardner, S. D.; Hollas, C. L.; Ussery, L. E. et al.
Object Type: Report
System: The UNT Digital Library
Nineteenth workshop on geothermal reservoir engineering: Proceedings (open access)

Nineteenth workshop on geothermal reservoir engineering: Proceedings

PREFACE The Nineteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 18-20, 1994. This workshop opened on a sad note because of the death of Prof. Henry J. Ramey, Jr. on November 19, 1993. Hank had been fighting leukemia for a long time and finally lost the battle. Many of the workshop participants were present for the celebration of his life on January 21 at Stanford's Memorial Church. Hank was one of the founders of the Stanford Geothermal Program and the Geothermal Reservoir Engineering Workshop. His energy, kindness, quick wit, and knowledge will long be missed at future workshops. Following the Preface we have included a copy of the Memorial Resolution passed by the Stanford University Senate. There were one hundred and four registered participants. Participants were from ten foreign countries: Costa Rica, England, Iceland, Italy, Japan, Kenya, Mexico, New Zealand, Philippines and Turkey. Workshop papers described the performance of fourteen geothermal fields outside the United States. Roland N. Home opened the meeting and welcomed the visitors to the campus. The key note speaker was J.E. ''Ted'' Mock who gave a presentation about the future of geothermal development. The banquet speaker was Jesus Rivera and he …
Date: January 20, 1994
Creator: Ramey, H.J. Jr.; Horne, R.J.; Kruger, P.; Miller, F.G.; Brigham, W.E. & Cook, J.W.
Object Type: Article
System: The UNT Digital Library
Large-area, triple-junction a-Si alloy production scale-up. Semiannual subcontract report, 17 March 1993--18 September 1993 (open access)

Large-area, triple-junction a-Si alloy production scale-up. Semiannual subcontract report, 17 March 1993--18 September 1993

This report describes work to improve the efficiency of large-area, multi-junction amorphous silicon (a-Si) alloy modules. Equipment capable of producing modules up to 0.74 m{sup 2} in area is on line and process development has begun. Preliminary cost analysis/reduction has begun to ensure that these development efforts will result in a commercialization of the large-area technology. The approach was to transfer the high-efficiency multi-junction technology from R&D into the manufacturing environment by using three different substrate sizes. Initial attempts to transfer the multijunction silicon process were made using a 0.1-m{sup 2} substrate (approximately 1 ft{sup 2}). These efforts resulted in a module with a measured aperture area efficiency of 10.32%. Simultaneous with the transfer of the silicon technology, the most complicated aspect of the technology transfer, Solarex began process development techniques on large-area modules by using the 0.37-m{sup 2} substrates. These efforts resulted in modules with a total area efficiency of 7%. Finally, initial runs on substrates 0.74 m{sup 2} were made to debug the large-area equipment in preparation of transferring the knowledge gained in the processing of the smaller substrates.
Date: March 1, 1994
Creator: Oswald, R.; O`Dowd, J. & Ashenfelter, W.
Object Type: Report
System: The UNT Digital Library
Potential applications of fusion neutral beam facilities for advanced material processing (open access)

Potential applications of fusion neutral beam facilities for advanced material processing

Surface processing techniques involving high energy ion implantation have achieved commercial success for semiconductors and biomaterials. However, wider use has been limited in good part by economic factors, some of which are related to the line-of-sight nature of the beam implantation process. Plasma source ion implantation is intended to remove some of the limitations imposed by directionality of beam systems and also to help provide economies of scale. The present paper will outline relevant technologies and areas of expertise that exist at Oak Ridge National Laboratory in relation to possible future needs in materials processing. Experience in generation of plasmas, control of ionization states, pulsed extraction, and sheath physics exists. Contributions to future technology can be made either for the immersion mode or for the extracted beam mode. Existing facilities include the High Power Test Facility, which could conservatively operate at 1 A of continuous current at 100 kV delivered to areas of about 1 m{sup 2}. Higher instantaneous voltages and currents are available with a reduced duty cycle. Another facility, the High Heat Flux Facility can supply a maximum of 60 kV and currents of up to 60 A for 2 s on a 10% duty cycle. Plasmas may …
Date: January 1, 1994
Creator: Williams, J. M.; Tsai, C. C.; Stirling, W. L. & Whealton, J. H.
Object Type: Article
System: The UNT Digital Library
Groundwater maps of the Hanford Site, December 1993 (open access)

Groundwater maps of the Hanford Site, December 1993

This report is an update to the series of reports that document the configuration of the uppermost unconfined aquifer beneath the Hanford Site. This series presents the latest results of the semiannual water level measurement program and the water table maps generated from these measurements. The reports document the changes in the groundwater level at the Hanford Site during the transition from nuclear material production to environmental restoration and remediation. In addition, these reports provide water level data to support the various site characterization and groundwater monitoring programs currently in progress on the Hanford Site. The three major operations areas (the 100, 200 and 300/1100 Areas) where wastes were discharged to the soil are covered in this update. The water level measurements from the wells in these areas are portrayed on a set of maps to illustrate the hydrologic conditions and are also tabulated in an appendix. A summary discussion of the data is included with the well index map, the depth to water map, and the contoured map of the water table surface for each of the three areas.
Date: July 1, 1994
Creator: Kasza, G. L.; Hartman, M. J.; Jordan, W. A. & Borghese, J. V.
Object Type: Report
System: The UNT Digital Library