States

Strange quarks in nuclei (open access)

Strange quarks in nuclei

We survey the field of strange particle nuclear physics, starting with the spectroscopy of strangeness S = {minus}1 {Lambda} hypernuclei, proceeding to an interpretation of recent data on S = {minus}2 {Lambda}{Lambda} hypernuclear production and decay, and finishing with some speculations on the production of multi-strange nuclear composites (hypernuclei or strangelets'') in relativistic heavy ion collisions. 41 refs., 5 figs.
Date: June 1, 1991
Creator: Dover, C. B.
Object Type: Article
System: The UNT Digital Library
Full scale field test of the in situ air stripping process at the Savannah River integrated demonstration test site (open access)

Full scale field test of the in situ air stripping process at the Savannah River integrated demonstration test site

Under sponsorship from the US Department of Energy, technical personnel from the Savannah River Laboratory (SRL) and other DOE laboratories, universities and private industry have completed a full scale demonstration of environmental remediation using horizontal wells. This demonstration was performed as Phase I of an Integrated Demonstration Project designed to evaluate innovative remediation technologies for environmental restoration of sites contaminated with organic contaminants. The demonstration utilized two directionally drilled horizontal wells to deliver gases and extract contaminants from the subsurface. The resulting in situ air stripping process was designed to remediate soils and sediments above and below the water table as well as groundwater contaminated with volatile organic contaminants. The 139 day long test successfully removed volatile chlorinated solvents from the subsurface using the two horizontal wells. One well, approximately 300 ft (90m) long and 165 ft (50m) deep drilled below a contaminant plume in the groundwater, was used to inject air and strip the contaminants from the groundwater. A second horizontal well, approximately 175 ft (53m) long and 75 ft (23m) deep in the vadose zone, was used to extract residual contamination in the vadose zone along with the material purged from the groundwater. Pretest and posttest characterization data …
Date: June 29, 1991
Creator: Looney, B. B.; Hazen, T. C.; Kaback, D. S. & Eddy, C. A.
Object Type: Report
System: The UNT Digital Library
Estimation of fracture toughness of cast stainless steels during thermal aging in LWR systems (open access)

Estimation of fracture toughness of cast stainless steels during thermal aging in LWR systems

A procedure and correlations are presented for predicting the change in fracture toughness of cast stainless steel components due to thermal aging during service in light water rectors (LWRs) at 280--330{degrees}C (535--625{degrees}F). The fracture toughness J-R curve and Charpy-impact energy of aged cast stainless steels are estimated from known mineral in formation. Fracture toughness of a specific cast stainless steel is estimated from the extent and kinetics of thermal embrittlement. The extent of thermal embrittlement is characterized by the room-temperature normalized'' Charpy-impact energy. A correlation for the extent of embrittlement at saturation,'' i.e., the minimum impact energy that would be achieved for the material after long-term aging, is given in terms of a material parameter, {Phi}, which is determined from the chemical composition. The fracture toughness J-R curve for the material is then obtained from correlations between room-temperature Charpy-impact energy and fracture toughness parameters. Fracture toughness as a function of time and temperature of reactor service is estimated from the kinetics of thermal embrittlement, which is determined from chemical composition. A common lower-bound'' J-R curve for cast stainless steels with unknown chemical composition is also defined for a given material specification, ferrite content, and temperature. Examples for estimating impact strength …
Date: June 1, 1991
Creator: Chopra, O.K. (Argonne National Lab., IL (USA))
Object Type: Report
System: The UNT Digital Library
Scanning tunneling microscopy studies of the surfaces of a-Si:H and a-SiGe:H films (open access)

Scanning tunneling microscopy studies of the surfaces of a-Si:H and a-SiGe:H films

The report contains a detailed description of the experimental complexities encountered in developing scanning tunneling microscope (STM) probing of atomic structure on the surface of freshly-grown hydrogenated-amorphous semiconductors. It also contains a speculative microscopic film-growth model that explains differences between the disorder in CVD grown a-Ge:H versus a-Si:H films. This model is derived from prior results obtained in the chemical analysis of GeH{sub 4} plasmas, combined with surface reaction and thermodynamic considerations. The neutral radical fragments of silane, disilane and germane dissociation in discharges, which dominate the vapor and film-growth reactions, have been deduced from detailed analysis of prior data and are reported. 4 refs., 7 figs.
Date: June 1, 1991
Creator: Gallagher, A.; Ostrom, R. & Tannenbaum, D. (National Inst. of Standards and Technology, Boulder, CO (USA))
Object Type: Report
System: The UNT Digital Library
Plasma injection and atomic physics models for use in particle simulation codes (open access)

Plasma injection and atomic physics models for use in particle simulation codes

Models of plasma injection (creation) and charged/neutral atomic physics which are suitable for incorporation into particle simulation codes are described. Both planar and distributed source injection models are considered. Results obtained from planar injection into a collisionless plasma-sheath region are presented. The atomic physics package simulates the charge exchange and impact ionization interactions which occur between charged particles and neutral atoms in a partially-ionized plasma. These models are applicable to a wide range of problems, from plasma processing of materials to transport in the edge region of a tokamak plasma. 18 refs., 6 figs.
Date: June 12, 1991
Creator: Procassini, R.J. (Lawrence Livermore National Lab., CA (USA) California Univ., Berkeley, CA (USA). Electronics Research Lab.)
Object Type: Report
System: The UNT Digital Library
Single-shell tank constituent rankings for use in preparing waste characterization plans (open access)

Single-shell tank constituent rankings for use in preparing waste characterization plans

Waste characterization efforts for underground single-shell tanks (SSTs) containing chemical and radioactive mixed wastes at the US Department of Energy's (DOE) Hanford Site are currently under way. As a component of this effort, an analysis was conducted to give a preliminary ranking of possible constituents in the SST waste and provide data for establishing detection limit requirements for the SST characterization effort. These SST constituent rankings were based on a relative comparison using potential human health impacts modeled using a hypothetical exposure scenario. This modeling effort used preliminary estimates of the SST inventories, simplified estimates of constituent release rates and environmental transport, a hypothetical usage location, and a standard Hanford exposure scenario. The results of this evaluation are SST constitutents for each of six groups of SSTs ranked according to their relative potential for impacts. The relative rankings for different recharge rates at the tank farms were nearly equivalent. Sensitivity tests demonstrated that the rankings are influenced by changes in recharge and transport parameters. 45 refs., 18 figs., 2 tabs.
Date: June 1, 1991
Creator: Droppo Jr., J. G.; Buck, J. W.; Wilbur, J. S.; Strenge, D. L. & Freshley, M. D.
Object Type: Report
System: The UNT Digital Library
Measurements of magnetization multipoles in four centimeter quadrupoles for the SSC (open access)

Measurements of magnetization multipoles in four centimeter quadrupoles for the SSC

Higher multipoles due to magnetization of the superconductor in superconducting dipole and quadrupole magnets has been observed in over twenty years. This report presents measurements of the 12 pole and 20 pole multipoles in a model one-meter long four-centimeter bore SSC type quadrupole built at the Lawrence Berkeley Laboratory (LBL). The measurements were compared with calculations of the field structure using magnetization theory. Good agreement was observed between the measured multipoles and the calculated multipoles. Under conditions equivalent to injection into the SSC at an energy of 2 TeV, about 1.0 unit of 12 pole was observed and 0.05 units of 20 pole was observed. (One unit of field error is a field error of one part in ten thousand). Magnetization multipole measurements were also done on the first full length (5 meter) SSC quadrupole prototype. Measurements of flux creep decay were made on three one meter quadrupoles and the first five meter long quadrupole. 7 refs., 9 figs.
Date: June 1, 1991
Creator: Green, M. A.; Barale, P. J.; Benjegerdes, R. W.; Gilbert, W. S.; Green, M. I.; Scanlan, R. M. et al.
Object Type: Article
System: The UNT Digital Library
Development of Alaskan Gas Hydrate Resources (open access)

Development of Alaskan Gas Hydrate Resources

The research undertaken in this project pertains to study of various techniques for production of natural gas from Alaskan gas hydrates such as, depressurization, injection of hot water, steam, brine, methanol and ethylene glycol solutions through experimental investigation of decomposition characteristics of hydrate cores. An experimental study has been conducted to measure the effective gas permeability changes as hydrates form in the sandpack and the results have been used to determine the reduction in the effective gas permeability of the sandpack as a function of hydrate saturation. A user friendly, interactive, menu-driven, numerical difference simulator has been developed to model the dissociation of natural gas hydrates in porous media with variable thermal properties. A numerical, finite element simulator has been developed to model the dissociation of hydrates during hot water injection process.
Date: June 1, 1991
Creator: Kamath, V. A.; Sharma, G. D. & Patil, S. L.
Object Type: Report
System: The UNT Digital Library
Chasing the x sub f dependence of J/. Psi. production (open access)

Chasing the x sub f dependence of J/. Psi. production

We discuss the combined effects of hard scattering processes and intrinsic heavy-quark components in the hadron wavefunction on the x{sub f} dependence of J/{psi} production. The A dependence arises from nuclear absorption, comover interactions, shadowing of parton distributions, and intrinsic heavy quarks. 9 refs., 1 fig.
Date: June 10, 1991
Creator: Vogt, R.
Object Type: Article
System: The UNT Digital Library
An idealized transient model for melt dispersal from reactor cavities during pressurized melt ejection accident scenarios (open access)

An idealized transient model for melt dispersal from reactor cavities during pressurized melt ejection accident scenarios

The direct Containment Heating (DCH) calculations require that the transient rate at which the melt is ejected from the reactor cavity during hypothetical pressurized melt ejection accident scenarios be calculated. However, at present no models, that are able to predict the available melt dispersal data from small scale reactor cavity models, are available. In this report, a simple idealized model of the melt dispersal process within a reactor cavity during a pressurized melt ejection accident scenario is presented. The predictions from the model agree reasonably well with the integral data obtained from the melt dispersal experiments using a small scale model of the Surry reactor cavity. 17 refs., 15 figs.
Date: June 1, 1991
Creator: Tutu, N.K.
Object Type: Report
System: The UNT Digital Library
An evaluation of some innovative fragmentation systems for oil shale (open access)

An evaluation of some innovative fragmentation systems for oil shale

This report describes a large-scale underground mining method, large-hole stoping, using some innovative fragmentation systems (buffer blasting, continuous loading/hauling, and mechanical miners for development). This study includes a literature review and an experimental study of one of the key design factors--buffer blasting. The purpose of the buffer-blasting experiments is to examine the swell that is necessary to achieve satisfactory fragmentation results. The study also includes a technical and economic evaluation of the new mining method compared with conventional room and pillar mining. The purpose of this study is to examine innovative methods that exist today and may provide a more efficient mining system than that currently used. Note that this is a conceptual study, and that the mining for the two mine designs were compared using a daily production rate of 75,000 tones per day. This amount was chosen because it is the maximum amount possible for a rubber-tired room and pillar operation with only a one-shaft complex.
Date: June 1991
Creator: Hieta, M. & Hustrulid, W.A. (Western Research Inst., Laramie, WY (United States))
Object Type: Report
System: The UNT Digital Library
Towards a realistic plasma simulation code (open access)

Towards a realistic plasma simulation code

Several new developments in the technology of simulating plasmas, both in particle and fluid models, now allow a stage of synthesis in which many of these advances can be combined into one simulation model. Accuracy and efficiency are the criteria to be satisfied in this quest. We want to build on the following research: 1. the development of the {delta}f method of Barnes. 2. The moving node Galerkin model of Glasser, Miller and Carlson. 3. Particle moving schemes on unstructured grids by Ambrosiano and Bradon. 4. Particle simulations using sorted particles Anderson and Shumaker. Rather than being competing developments,these presumably can be combined into one computational model. We begin by summarizing the physics model for the plasma. The Vlasov equation can be solved as an initial value problem by integrating the plasma distribution function forward in time. 5 refs.
Date: June 1, 1991
Creator: Anderson, D.V.
Object Type: Article
System: The UNT Digital Library
An exponential model for HPGe detector efficiencies (open access)

An exponential model for HPGe detector efficiencies

Interest in reducing the labor-intensive requirements for calibrating HPGe detectors has resulted in various efficiency models. The present study examines a method for predicting the efficiencies over ranges of sample geometries, whereby only a few measurements are required. The method has been appraised against extensive HPGe calibrations, and has been used for a nondestructive'' calibration for samples from a NASA satellite.
Date: June 11, 1991
Creator: Winn, Willard G.
Object Type: Article
System: The UNT Digital Library
First turn around strategy for RHIC (open access)

First turn around strategy for RHIC

We present a strategy for achieving the so-called first turn around in RHIC. The strategy is based on the same method we had proposed to correct a distorted closed orbit in RHIC, i.e., on a generalization of the local three-bump method. We found out that the method is very effective in passing the beam through a non-ideal, insufficiently known, machine. We tested that software on ten different Gaussian distributions of dominant orbit distorting lattice imperfections. The perturbed lattice was generated by the code PATRIS, which was also adapted to control the newly developed software. In all of the ten distributions the software was capable of passing the beam through in 2--3 injection attempts, at full sextupole strength. It was also determined that once the beam makes the first turn around and all the correctors are energized, it stays in the machine for at least several hundred turns that we had checked. The quality of the orbit, that was established in this way, was also found to be very good, i.e., the residual distortions at the places of large beta function were much less than one millimeter. With one or two monitors/correctors broken, the software established a first turn around without …
Date: June 1, 1991
Creator: Milutinovic, J. & Ruggiero, A. G.
Object Type: Report
System: The UNT Digital Library
Cellular energy metabolism (open access)

Cellular energy metabolism

Studies have been carried out on adenylate kinase which is an important enzyme in determining the concentrations of the adenine nucleotides. An efficient method has been developed to clone mutant adenylate kinase genes in E. coli. Site-specific mutagenesis of the wild type gene also has been used to obtain forms of adenylate kinase with altered amino acids. The wild type and mutant forms of adenylate kinase have been overexpressed and large quantities were readily isolated. The kinetic and fluorescence properties of the different forms of adenylate kinase were characterized. This has led to a new model for the location of the AMP and ATP bindings sites on the enzyme and a proposal for the mechanism of substrate inhibition. Crystals of the wild type enzyme were obtained that diffract to at least 2.3 {angstrom} resolution. Experiments were also initiated to determine the function of adenylate kinase in vivo. In one set of experiments, E. coli strains with mutations in adenylate kinase showed large changes in cellular nucleotides after reaching the stationary phase in a low phosphate medium. This was caused by selective proteolytic degradation of the mutant adenylate kinase caused by phosphate starvation.
Date: June 1, 1991
Creator: Glaser, M.
Object Type: Report
System: The UNT Digital Library
Research on stable, high-efficiency, large-area, amorphous-silicon-based submodules (open access)

Research on stable, high-efficiency, large-area, amorphous-silicon-based submodules

The primary objective of this subcontract is to develop the technology for same bandgap, amorphous silicon tandem junction photovoltaic modules having an area of at least 900 cm{sup 2} with the goal of achieving an aperture area efficiency of 9%. A further objective is to demonstrate modules that retain 95% of their under standard light soaking conditions. Our approach to the attainment of these objective is based on the following distinctive technologies: (a) in-house deposition of SiO{sub 2}/SnO{sub 2}:F onto soda lime glass by APCVD to provide a textured, transparent electrode, (b) single chamber r.f. flow discharge deposition of the a-Si:H layers onto vertical substrates contained with high package density in a box carrier'' to which the discharge is confined (c) sputter deposition of highly reflecting, ZnO-based back contacts, and (d) laser scribing of the a-Si:H and electrodes with real-time scribe tracking to minimize area loss. Continued development of single junction amorphous silicon was aggressively pursued as proving ground for various optical enhancement schemes, new p-layers, and i-layers quality. We have rigorously demonstrated that the introduction of a transitional i-layer does not impair stability and that the initial gain in performance is retained. We have demonstrated a small improvement in …
Date: June 1, 1991
Creator: Delahoy, A.E.; Tonon, T. & Macneil, J. (Chronar Corp., Princeton, NJ (USA))
Object Type: Report
System: The UNT Digital Library
Adolescent Health, Volume 3: Crosscutting Issues in the Delivery of Health and Related Services (open access)

Adolescent Health, Volume 3: Crosscutting Issues in the Delivery of Health and Related Services

OTA’s report responds to the request of numerous Members of Congress to review the physical, emotional, and behavioral health status of contemporary American adolescents, including adolescents in groups who might be more likely to be in special need of health-related interventions: adolescents living in poverty, adolescents from racial and ethnic minority groups, Native American adolescents, and adolescents in rural areas.
Date: June 1991
Creator: United States. Congress. Office of Technology Assessment.
Object Type: Report
System: The UNT Digital Library
Agricultural Commodities as Industrial Raw Materials (open access)

Agricultural Commodities as Industrial Raw Materials

This report examines potential new crops and traditional crops for industrial uses including replacements for petroleum and imported strategic materials; replacements for imported newsprint, wood rosins, rubbers, and oils; and degradable plastics. This report finds that, in the absence of additional and more comprehensive policies, developing industrial uses for agricultural commodities alone is unlikely to revitalize rural economies and solve the problems of American agriculture.
Date: June 1991
Creator: United States. Congress. Office of Technology Assessment.
Object Type: Report
System: The UNT Digital Library
Moving Ahead: 1991 Surface Transportation Legislation (open access)

Moving Ahead: 1991 Surface Transportation Legislation

This report discusses the major issues surrounding the reauthorization of highway and transit legislation is laid out and four illustrative types of surface transportation programs are presented in chapters 1 and 2. Chapter 3 is devoted to the discussion of motor carrier programs, with special attention to issues related to longer combination trucks.
Date: June 1991
Creator: United States. Congress. Office of Technology Assessment.
Object Type: Report
System: The UNT Digital Library
Deflagration studies on waste Tank 101-SY: Test plan (open access)

Deflagration studies on waste Tank 101-SY: Test plan

This report discusses test procedures and calibration of equipment to study the flammability and deflagration of hydrogen, nitrous oxide, and air in waste tanks. (JL)
Date: June 1, 1991
Creator: Cashdollar, K. L.; Zlochower, I. A. & Hertzberg, M.
Object Type: Report
System: The UNT Digital Library
Analytical Methods for Malachite Green : Completion Report : Malachite Green Analysis in Water. (open access)

Analytical Methods for Malachite Green : Completion Report : Malachite Green Analysis in Water.

Malachite green is a known teratogen and therefore its use is limited to nonfood fish under an Investigational New Animal Drug permit (INAD), number 2573. Although a charcoal adsorption column was developed to remove malachite green from hatchery water, INAD compliance requires that the malachite green residue concentrations in any effluent from hatcheries using the chemical be quantified. Therefore, we developed a method for the analysis of malachite green residues in water. Enrichment of the residues of malachite green in water on a diol column followed by High Performance Liquid Chromatographic (HPLC) analysis gives a minimum sensitivity of less than 10 ppb for the chemical. When combined with post-column oxidation using a lead oxide post-column reactor, the procedure can be used for the simultaneous analysis of malachite green in its leuco form, a decomposition product of the dye, as well as its chromatic form. Recovery of the leuco form is pH dependent and water samples should be adjusted to pH 6 to optimize recovery of this form. Water samples spiked with malachite green were concentrated on a diol column followed by elution with 0.05 M p-toluene sulfonic acid in methanol. The methanol elutes were analyzed by HPLC. Pond water samples …
Date: June 1, 1991
Creator: Allen, John L.; Gofus, Jane E. & Meinertz, Jeffery R.
Object Type: Report
System: The UNT Digital Library
Organizational Cultural Assessment of the Idaho National Engineering Laboratory (open access)

Organizational Cultural Assessment of the Idaho National Engineering Laboratory

An Organizational Cultural Assessment (OCA) was performed at the Idaho National Engineering Laboratory (INEL) by administering an Organizational Culture Survey (OCS) that queried employees on the subjects of organizational culture, various aspects of communications, employee commitment, work group cohesion, coordination of work, environmental concerns, hazardous nature of work, safety and overall job satisfaction. Many of these subjects are assessed in the OCS through highly developed and validated scales that have been administered in many different types of organizations. The purpose of the OCS is to measure in a quantitative and objective way the notion of culture;'' that is, the values, attitudes, and beliefs of the individuals working within the organization. In addition, through the OCS, a broad sample of individuals can be reached that would probably not be interviewed or observed during the course of a typical assessment. The OCS also provides a descriptive profile of the organization at one point in time that can then be compared to a profile taken at a different point in time to assess changes in the culture of the organization. The OCS administration at the INEL was the sixth to occur at a Department of Energy (DOE) facility. The INEL Organization is somewhat …
Date: June 1, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The International Coal Statistics Data Base user's guide (open access)

The International Coal Statistics Data Base user's guide

The ICSD is a microcomputer-based system which presents four types of data: (1) the quantity of coal traded between importers and exporters, (2) the price of particular ranks of coal and the cost of shipping it in world trade, (3) a detailed look at coal shipments entering and leaving the United States, and (4) the context for world coal trade in the form of data on how coal and other primary energy sources are used now and are projected to be used in the future, especially by major industrial economies. The ICSD consists of more than 140 files organized into a rapid query system for coal data. It can operate on any IBM-compatible microcomputer with 640 kilobytes memory and a hard disk drive with at least 8 megabytes of available space. The ICSD is: 1. A menu-driven, interactive data base using Dbase 3+ and Lotus 1-2-3. 2. Inputs include official and commercial statistics on international coal trade volumes and consumption. 3. Outputs include dozens of reports and color graphic displays. Output report type include Lotus worksheets, dBase data bases, ASCII text files, screen displays, and printed reports. 4. Flexible design permits user to follow structured query system or design his …
Date: June 1, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Technology transfer from the space exploration initiative (open access)

Technology transfer from the space exploration initiative

Space exploration has demonstrated that it stimulates the national economy by creating new and improved products, increased employment, and provides a stimulus to education. The exploration of the Moon and Mars under the Space Exploration Initiative has the potential of accelerating this stimulates to the economy. It is difficult to identify all of the concrete ways this will be accomplished. However, many areas can be identified. The space exploration building blocks of power, propulsion, spacecraft, robotics, rovers, mining and manufacturing, communications, navigation, habitats, life support and infrastructures are reviewed to identify possible technology areas. For example, better means for working in hazardous areas and handling hazardous waste are potential outcomes of this initiative. Methods to produce higher quality goods and improve America's competitiveness in manufacturing will undoubtedly evolve from the need to produce products that must last many years in the harsh environments of space and planetary surfaces. Some ideas for technology transfer are covered in this paper.
Date: June 14, 1991
Creator: Buden, D.
Object Type: Article
System: The UNT Digital Library