States

BEAR electrostatic analyzer: Flight results (open access)

BEAR electrostatic analyzer: Flight results

The Electrostatic Analyzer (ESA) measured the intensity of charged particles returning to the BEAR payload during flight on 13 July 1989. These particles form part or all of the current that returns to the payload to neutralize the charge ejected with the beam. By measuring the return flux with high time resolution, we can study the physics of charging processes. When the neutralizer was off, the payload emitted 10 mA negative and charged to several hundred volts with a maximum of{approximately}800V. With the neutralizer on (normal configuration) the payload emitted {approximately} 1mA negative and received electrons with energies up to a few hundred volts in some attitudes. This suggests charging to a few hundred volts. The charging rate of the payload is consistent with the rocket body capacitance with respect to a vacuum. 1 ref., 14 figs.
Date: January 3, 1990
Creator: Anderson, Hugh R.; Potter, Douglas W.; Morse, David L.; Olson, Joseph R.; Johnson, J. Lorraine & Pongratz, Morris
Object Type: Article
System: The UNT Digital Library
Background-reducing x-ray multilayer mirror (open access)

Background-reducing x-ray multilayer mirror

This invention is comprised of a background-reducing x-ray multilayer mirror. A multiple-layer ``wavetrap`` deposited over the surface of a layered synthetic microstructure soft x-ray mirror optimized for reflectivity at chosen wavelengths is disclosed for reducing the reflectivity of undesired, longer wavelength incident radiation incident thereon. In three separate mirror designs employing an alternating molybdenum and silicon layered mirrored structure overlaid by two layers of a molybdenum/silicon pair anti-reflection coating, reflectivities of near normal incidence 133, 171, and 186 {Angstrom} wavelengths have been optimized, while that at 304 {Angstrom} has been minimized. The optimization process involves the choice of materials, the composition of the layer/pairs as well as the number thereof, and the distance therebetween for the mirror, and the simultaneous choice of materials, the composition of the layer/pairs, their number and distance for the ``wavetrap.``
Date: August 3, 1990
Creator: Bloch, J. J.; Roussel-Dupre, D. & Smith, B. W.
Object Type: Patent
System: The UNT Digital Library
Fission decay in intermediate heavy ion reactions (open access)

Fission decay in intermediate heavy ion reactions

Results are presented on cross sections, parallel and perpendicular momentum transfers, charge loss and velocity systematics for fission following reactions of Fe and Nb projectiles at 50--100 MeV/A on targets of Ta, Au, and Th. The results at 100 MeV/A are compared to a detailed multistage deexcitation model. The initial collision is modeled with an intranuclear cascade. The resultant excited target residues then undergo a fast preequilibrium decay stage followed by a statistical decay involving nucleon evaporation and fission. Results from this modeling are in reasonable agreement with experimental data. 14 refs., 11 figs.
Date: October 3, 1990
Creator: Britt, Harold C.
Object Type: Article
System: The UNT Digital Library
Stochastic analysis of contaminant transport: One-dimensional non-reactive and reactive cases (open access)

Stochastic analysis of contaminant transport: One-dimensional non-reactive and reactive cases

A reliability approach for probabilistic modeling of one-dimensional non-reactive and reactive transport in porous media provides two important quantitative results: (1) an estimate of the probability that dimensionless concentration equals or exceeds some specified level and, (2) the sensitivity of the probabilistic outcome to likely changes in each uncertain variable. The reliability approach is particularly attractive because it can incorporate various marginal probability density functions (PDF) for any of the uncertain variables. In this work uncertain variables include: groundwater flow velocity, diffusion coefficient, dispersivity, distribution coefficient, porosity and bulk density. The primary objective is to examine how the probabilistic outcome is influenced by choice of marginal PDF, correlation and magnitude of uncertainty for the variables. Because little information exists concerning the statistical characteristics of these uncertain variables, the investigation assumes a wide range of PDF types and statistical values in order to identify and isolate the most critical issues for further study. Results indicate that, even for very slow mean velocity, the probability estimate for non-reactive transport is most sensitive to uncertain flow velocity. For practical analysis, it appears acceptable to treat dispersivity as a deterministic constant. For non-reactive transport, correlation between flow velocity and diffusion coefficient has a slight …
Date: December 3, 1990
Creator: Cawlfield, J.D. & Wu, Ming-Chee.
Object Type: Report
System: The UNT Digital Library
A lattice gas model for thermohydrodynamics (open access)

A lattice gas model for thermohydrodynamics

The FHP lattice gas model is extended to include a temperature variable in order to study thermohydrodynamics. The compressible Navier-Stokes equations are derived using a Chapman-Enskog expansion. Heat conduction and convention problems are investigated, including Benard convention. It is shown that the usual FHP rescaling procedure can be avoided by controlling the temperature. 20 refs., 12 figs.
Date: May 3, 1990
Creator: Chen, Shiyi; Chen, Hudong; Doolen, G. D.; Gutman, S. & Lee, M.
Object Type: Article
System: The UNT Digital Library
Tags and seals to strengthen arms control verification (open access)

Tags and seals to strengthen arms control verification

Tags and seals have long been recognized as important tools in arms control. The trend in control of armaments is to limit militarily significant equipment that is capable of being verified through direct and cooperative means, chiefly on-site inspection or monitoring. Although this paper will focus on the CFE treaty, the role of tags and seals for other treaties will also be addressed. Published technology and concepts will be reviewed, based on open sources. Arms control verification tags are defined as unique identifiers designed to be tamper-revealing; in that respect, seals are similar, being used as indicators of unauthorized access. Tamper-revealing tags are intended as single-point markers, seals for two-point couplings, and nets for volume containment. Seals usually bind two separate components, such as a hatch or flange that provides access to a secure compartment or a valve that controls fluid flow. A tamper-revealing net might be comprised of a coupled fiberoptic bundle wrapped around an object. Sometimes the term ``seal`` is used to denote the tamper-revealing feature of a tag that is attached to a surface, but in this paper the tamper-indicating connection is considered to be part of the tag concept itself.
Date: October 3, 1990
Creator: DeVolpi, A.
Object Type: Report
System: The UNT Digital Library
Dual output acoustic wave sensor for molecular identification (open access)

Dual output acoustic wave sensor for molecular identification

The invention comprises a method for the identification and quantification of sorbed chemical species onto a coating of a device capable of generating and receiving an acoustic wave, by measuring the changes in the velocity of the acoustic wave resulting from the sorption of the chemical species into the coating as the wave travels through the coating and by measuring the changes in the attenuation of an acoustic wave resulting from the sorption of the chemical species into the coating as the wave travels through the coating. The inventive method further correlates the magnitudes of the changes of velocity with respect to changes of the attenuation of the acoustic wave to identify the sorbed chemical species. The absolute magnitudes of the velocity changes or the absolute magnitude of the attenuation changes are used to determine the concentration of the identified chemical species.
Date: October 3, 1990
Creator: Frye, G. C. & Martin, S. J.
Object Type: Patent
System: The UNT Digital Library
Fermilab Library projects (open access)

Fermilab Library projects

Preprint database management as done at various centers -- the subject of this workshop -- is hard to separate from the overall activities of the particular center. We therefore present the wider context at the Fermilab Library into which preprint database management fits. The day-to-day activities of the Library aside, the dominant activity at present is that of the ongoing Fermilab Library Automation. A less dominant but relatively time-consuming activity is that of doing more online searches in commercial databases on behalf of laboratory staff and visitors. A related activity is that of exploring the benefits of end-user searching of similar sources as opposed to library staff searching of the same. The Library Automation Project, which began about two years ago, is about to go fully online.'' The rationale behind this project is described in the documents developed during the December 1988--February 1989 planning phase.
Date: May 3, 1990
Creator: Garrett, P. & Ritchie, D.
Object Type: Article
System: The UNT Digital Library
A study of tau decays of the W boson at CDF (Collider Detector at Fermilab) (open access)

A study of tau decays of the W boson at CDF (Collider Detector at Fermilab)

A report is given of a search for tau decays of the W boson in p{bar p} collisions at {radical}s = 1.8 TeV using the Collider Detector at Fermilab (CDF). A description of a hardware trigger specifically designed to enhance the number of events with tau decays is presented along with the results of a preliminary analysis of data taken during the 1988--89 run of CDF. 10 refs., 4 figs.
Date: January 3, 1990
Creator: Gladney, L. D.
Object Type: Article
System: The UNT Digital Library
MGA (Multi-Group Analysis): A Gamma-Ray Spectrum Analysis Code for Determining Plutonium Isotopic Abundances (open access)

MGA (Multi-Group Analysis): A Gamma-Ray Spectrum Analysis Code for Determining Plutonium Isotopic Abundances

Nondestructive measurements of x-ray and gamma-ray emissions can be used to analyze a sample for plutonium. This report describes the methods and algorithms we have developed for analyzing gamma-ray spectra obtained by using a germanium detector system to accurately determine the relative abundances of various actinide isotopes in a sample. Our methodology requires no calibrations and can be used to measure virtually any size and type of plutonium sample. Measurement times can be as short as a few minutes; measurements are frequently accurate to within 1%. Our methods have been programmed into a computerized analysis code called MGA (Multi-Group Analysis). Our current versions can be run on personal computers (IBM type) and on the DEC VAX microcomputer. Spectral analysis times are usually far less than a minute. 28 refs., 26 figs., 1 tab.
Date: April 3, 1990
Creator: Gunnink, R
Object Type: Report
System: The UNT Digital Library
The role of imaging in advanced document systems: Reviews of computing technology (open access)

The role of imaging in advanced document systems: Reviews of computing technology

This report discusses the following topics on imaging technology in advanced document systems: supporting technology; current state of image systems; and future directions of image systems.
Date: December 3, 1990
Creator: Hudson, B. J.
Object Type: Report
System: The UNT Digital Library
The role of imaging in advanced document systems: Reviews of computing technology (open access)

The role of imaging in advanced document systems: Reviews of computing technology

This report discusses the following topics on imaging technology in advanced document systems: supporting technology; current state of image systems; and future directions of image systems.
Date: December 3, 1990
Creator: Hudson, B.J.
Object Type: Report
System: The UNT Digital Library
(Coordinated research programs in nuclear medicine) (open access)

(Coordinated research programs in nuclear medicine)

The traveler visited the Clinic for Nuclear Medicine at the University of Bonn, West Germany, to review, organize, and plan collaborative studies. He also met with the editorial board of the journal NucCompact -- European/American Communications in Nuclear Medicine, on which he serves as US editor. He also visited colleagues at the Cyclotron Research Center (CRC) at the University of Liege, Belgium, to coordinate clinical applications of the ultrashort-lived iridium-191m radionuclide obtained from the osmium-190/iridium-191m generator system. The traveler planned and coordinated continuing collaboration with colleagues at the CRC for further applications of this generator system. He also visited the University of Metz, Metz, France, to organize a three-center project for the synthesis and evaluation of various receptor-specific cerebral imaging agents, involving the Oak Ridge National Laboratory (ORNL), CRC, and the University of Metz.
Date: October 3, 1990
Creator: Knapp, F. F. Jr.
Object Type: Report
System: The UNT Digital Library
Fluid dynamics of double diffusive systems (open access)

Fluid dynamics of double diffusive systems

The major accomplishments of our initial research period (August 1, 1987, to March 1, 1990) are as follows; we completed construction of the experimental facility. Originally, it had been our intent to modify an existing facility in our laboratory. When this became impractical we constructed a new stand-alone facility. Modified an existing three-dimensional numerical code developed in our laboratory, SEAFLOS1, by incorporating a salinity transport equation. Developed experimental and analytical techniques, and performed both physical and numerical experiments for a wide range of initial and boundary conditions. Focused our overall research effort to answer the following four questions pertaining to the formation of convective intrusions due to lateral temperature gradients established by sidewall heating. (1) What is the internal structure of the convective intrusions as a function of the initial stratification and sidewall heating rates (2) What is the correct scaling for the initial vertical dimension of the intrusions (3) How does the merging process vary as a function of initial stratification and sidewall heating rate (4) Is the sidewall heating critical for continued propagation of the intrusions, or is it merely a trigger which releases the internal instability in the fluid
Date: April 3, 1990
Creator: Koseff, J. R.
Object Type: Report
System: The UNT Digital Library
Extraction of Potential Pollutants From Ohio Coal by Synergistic Use of Supercritical Fluids. Final Report (open access)

Extraction of Potential Pollutants From Ohio Coal by Synergistic Use of Supercritical Fluids. Final Report

A synergistic supercritical extraction process was developed and its feasibility demonstrated using a semi-batch extraction process unit. The process was found to be effective in selectively cleaning organic sulfur from Ohio coals. Optimal case involved a mixture of CO{sub 2}, H{sub 2}O, and CH{sub 3}OH, and the removal of organic sulfur ranged from 35 to 55%. Combined with pyrite and mineral matter removal by gravity, the resulting coals would have 20--30% increased heating values and SO{sub 2} emissions would be down to 1.2--1.5 pounds per million Btu, thus meeting compliance requirements. Estimated cleaning cost including pyrite removal is $25 to 45 per ton. The most important cost factor is the operation at high pressures.
Date: August 3, 1990
Creator: Lee, S.
Object Type: Report
System: The UNT Digital Library
DAB, South Side, ODH Analysis (open access)

DAB, South Side, ODH Analysis

This report covers the ODH concerns of the south side of the D0 Assembly Building. from the bottom (el. 700-feet) to the top (774-feet 6-inches). volume by volume. Each volume is covered in its own section. with each section broken down into three parts. The first is a description of the volume. including its function. dimensions. and all relative ODH concerns; cryogenic piping and ventilation. Second. the actual ODH analysis of the volume is shown. Third. the provisions for the ODH condition of the volume are detailed. including securing the area and the posting of signs. The liquid argon dewar room is at an elevation of 701-feet 6-inch (38-feet underground), with the dewar surrounded by 7700 cubic feet of air. The area is accessible only through a single door. which has a small window and a lock (lock out only). There is small metal scaffolding in front of the dewar to facilitate maintenance and U-tube pulling and installation. The room is directly on top of the Pipe Chase Well and the Cryo Sump, and the bottom of the Stairway is just outside the door. The dewar is designed to be completely operated by remote computer control and the area will …
Date: January 3, 1990
Creator: Michael, J. & Mulholland, G. T.
Object Type: Report
System: The UNT Digital Library
A Fast Online Event Display for a High Intensity Fixed-Target Spectrometer (open access)

A Fast Online Event Display for a High Intensity Fixed-Target Spectrometer

A workstation-based event display program for the Fermilab Tagged Photon Spectrometer (TPS) is described. Fast displays are required to monitor detector elements, observe hit patterns and energy deposition, and to check track reconstruction. Design considerations, novel features, and performance are designed. 5 refs., 4 figs., 1 tab.
Date: May 3, 1990
Creator: Napier, Austin
Object Type: Article
System: The UNT Digital Library
Modeling the response of plants and ecosystems to global change. Progress report, September 1, 1989--August 31, 1990 (open access)

Modeling the response of plants and ecosystems to global change. Progress report, September 1, 1989--August 31, 1990

An initiated close collaboration with experimentalists at Kansas State University that will provide data necessary to models of response to global change. This collaboration also includes co-operative experimental work carried out by staff at SERG that expands the range of ecosystem level processes measured in the open top chambers at Manhatan, Kansas. Several factors suggest that close co-operation between our two groups will be especially advantageous for the realization of the broad goals of the DOE CO{sub 2} consortium: (1) The experimental effort is very extensive, chambers and smaller closed chambers are experiments will provide information at levels. (2) We have been in close contact with the Kansas State group for some time and are beginning a major addition to the open chamber studies this summer. Consequently, we will be present at the field site for much of the summer, working directly with the group. (3) Several members of our group have extensive experience working in grasslands and our ecosystem model is currently well structured to handle grassland simulations.
Date: May 3, 1990
Creator: Reynolds, J. F.; Harley, P.; Hilbert, D. W.; Kemp, P. R.; Cornelius, J. M. & Tenhunen, J. D.
Object Type: Report
System: The UNT Digital Library
End Cap Calorimeter Annular Space Pipe Cleaning Procedures (open access)

End Cap Calorimeter Annular Space Pipe Cleaning Procedures

None
Date: December 3, 1990
Creator: Rucinski, R.
Object Type: Report
System: The UNT Digital Library
San Antonio Monthly Reports: June 1990 [Part 2] (open access)

San Antonio Monthly Reports: June 1990 [Part 2]

Compilation of monthly reports from departments in the city of San Antonio, Texas providing statistics, project updates, and other information about services and activities.
Date: July 3, 1990
Creator: San Antonio (Tex.)
Object Type: Report
System: The Portal to Texas History
San Antonio Monthly Reports: March 1990 [Part 1] (open access)

San Antonio Monthly Reports: March 1990 [Part 1]

Compilation of monthly reports from departments in the city of San Antonio, Texas providing statistics, project updates, and other information about services and activities.
Date: March 3, 1990
Creator: San Antonio (Tex.)
Object Type: Report
System: The Portal to Texas History
San Antonio Monthly Reports: March 1990 [Part 2] (open access)

San Antonio Monthly Reports: March 1990 [Part 2]

Compilation of monthly reports from departments in the city of San Antonio, Texas providing statistics, project updates, and other information about services and activities.
Date: April 3, 1990
Creator: San Antonio (Tex.)
Object Type: Report
System: The Portal to Texas History
San Antonio Monthly Reports: November 1990 (open access)

San Antonio Monthly Reports: November 1990

Compilation of monthly reports from departments in the city of San Antonio, Texas providing statistics, project updates, and other information about services and activities.
Date: December 3, 1990
Creator: San Antonio (Tex.)
Object Type: Report
System: The Portal to Texas History
The Crystal Structures and Powder Diffraction Patterns of the Uranium Tellurides (open access)

The Crystal Structures and Powder Diffraction Patterns of the Uranium Tellurides

A critical review of all of the reported structures and powder diffraction patterns in the uranium telluride system has been undertaken. Structures that are correct: Cubic -- UTe: no experimental pattern exists. Retain calculated 15--865. Cubic --U{sub 3}Te{sub 4}: retain the poor quality 12--610 but adopt the pattern calculated here. Cubic U{sub 2}Te{sub 3}: no experimental pattern exists. Adopt pattern calculated here. Orthorhombic UTe{sub 2}: Adopt the new pattern of Boehme et al. Monoclinic {alpha}UTe{sub 3} Adopt the new pattern of Boehme et al. Monoclinic {alpha}UTe{sub 3} Adopt the new pattern of Boehme et al. Orthorhombic {beta}UTe{sub 3}: Adopt pattern calculated here. Orthorhombic UTe{sub 5}: Adopt the new pattern of Boehme et al. Structures in need of refinement: Orthorhombic U{sub 2}Te{sub 3}:Adopt pattern calculated here over 34--807. Hexagonal U{sub 7}Te{sub 12}: Adopt pattern calculated here but retain 24--1368. Orthorhombic UTe{sub 1.78}: Adopt pattern calculated here and retain our modified 21--1404 reported for U{sub 4}Te{sub 7}. Orthorhombic UTe{sub 2.5}: Adopt pattern calculated here. Orthorhombic UTe{sub 3.4}: Accept recent pattern of Boehme et al. Phases for which no structures or reliable patterns exist: Orthorhombic U{sub 3}Te{sub 4}: no published pattern. Tetragonal U{sub 3}Te{sub 5}: three patterns 21--1407, 34--766 and 34--896 exit but …
Date: October 3, 1990
Creator: Snyder, Robert L.; Nichols, Monte C. & Boehme, Dale R.
Object Type: Report
System: The UNT Digital Library