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Implications of the 17 keV neutrino (open access)

Implications of the 17 keV neutrino

Constraints on the theoretical interpretation of the 17 keV neutrino are reviewed. A simple understanding of the 17 keV neutrino is provided by flavon models, which involve the spontaneous breaking of Abelian lepton symmetries and have only the usual three light neutrino species. Signatures for this class of models include neutrino oscillations, tau decay to an electron and a flavon, and invisible decay modes of the Higgs boson to two flavons.
Date: June 1, 1991
Creator: Hall, L. J.
System: The UNT Digital Library
A computer-based building design support environment (open access)

A computer-based building design support environment

Continuously decreasing cost has brought computers into most architectural and engineering offices, most commonly for activities such as drafting, accounting and word processing. Computers are used less often to predict the performance of design solutions. However, most performance simulation software packages are simplified versions of main-frame analytical tools, originally developed for research. Such software packages focus on specific design issues according to the research needs. Also, the data input requirements are complicated and incompatible with each other, and the output data are usually specialized and difficult to interpret. It is yet to be seen how the increasing memory and processing speed of computers, the two main advantages that computers have over the human brain, can be used to assist designers throughout the design process, allowing them to organize design projects electronically. We describe the design and initial implementation of a computer-based Building Design Support Environment whose structure and operation are derived from a detailed theoretical analysis of the design process, into the iterative and interactive activities that contribute towards the formulation of design criteria, the generation of potential solutions, and their evaluation. The identified design activities are characterized with respect to the nature of knowledge requirements and the degree to …
Date: June 1, 1991
Creator: Papamichael, K. & Selkowitz, S. E.
System: The UNT Digital Library
Criticality safety and facility design considerations (open access)

Criticality safety and facility design considerations

Operations with fissile material introduce the risk of a criticality accident that may be lethal to nearby personnel. In addition, concerns over criticality safety can result in substantial delays and shutdown of facility operations. For these reasons, it is clear that the prevention of a nuclear criticality accident should play a major role in the design of a nuclear facility. The emphasis of this report will be placed on engineering design considerations in the prevention of criticality. The discussion will not include other important aspects, such as the physics of calculating limits nor criticality alarm systems.
Date: June 1, 1991
Creator: Waltz, W. R.
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, W. G.
System: The UNT Digital Library
Minorities and air quality non-attainment areas: A preliminary geo-demographic analysis (open access)

Minorities and air quality non-attainment areas: A preliminary geo-demographic analysis

A major section of the Clean Air Act Amendments (CAAA) focuses on reducing air pollution through extending and modifying the provisions for states and localities with US Environmental Protection Agency (EPA)-designated non-attainment areas. Specifically, Title 1 of the CAAA is concerned with non-attainment areas, as defined relative to the National Ambient Air Quality Standards for atmospheric ozone, carbon monoxide, and particulate matter; Title 2 is concerned with mobile sources or air pollution, which produce carbon monoxide, contribute to ozone concentrations, and in the past have been a major source of airborne lead; and Title 4 is concerned with acid deposition, mainly due to sulfur dioxide emissions. This paper has its origin in the question of the potential benefits for minorities--relative to the majority non-Black, non-Hispanic population--of reductions in air pollution that may result from these amendments. It is part of a larger effort to identify and assess the costs and benefits of the CAAA for minorities, relative to the majority population. The focus of this paper centers on comparing Black and Hispanic populations to White, non-Hispanic populations living in EPA-designated non-attainment area counties in the contiguous United States, which excludes Alaska and Hawaii. Subsequent comparisons of majority populations with Native …
Date: June 1, 1991
Creator: Wernette, D. & Nieves, L.
System: The UNT Digital Library
Hanford Tank Safety Project: Minutes of the Tank Waste Science Panel meeting, February 7--8, 1991 (open access)

Hanford Tank Safety Project: Minutes of the Tank Waste Science Panel meeting, February 7--8, 1991

The Tank Waste Science Panel met February 7--8, 1991, to review the latest data from the analyses of the October 24, 1990, gas release from Tank 241-SY-101 (101-SY) at Hanford; discuss the results of work being performed in support of the Hanford Tank Safety Project; and be briefed on the ferrocyanide issues included in the expanded scope of the Science Panel. The shapes of the gas release curves from the past three events are similar and correlate well with changes in waste level, but the correlation between the released volume of gas and the waste height is not as good. An analysis of the kinetics of gas generation from waste height measurements in Tank 101-SY suggests that the reaction giving rise to the gases in the tank is independent of the gas pressure and independent of the physical processes that give rise to the episodic release of the gases. Tank waste height data were also used to suggest that a floating crust formed early in the history of the tank and that the current crust is being made thicker in the eastern sector of the tank by repeated upheaval of waste slurry onto the surface. The correlation between the N{sub …
Date: June 1, 1991
Creator: Strachan, D. M.
System: The UNT Digital Library
Thin-film forces in pseudoemulsion films (open access)

Thin-film forces in pseudoemulsion films

Use of foam for enhanced oil recovery (EOR) has shown recent success in steam-flooding field applications. Foam can also provide an effective barrier against gas coning in thin oil zones. Both of these applications stem from the unique mobility-control properties a stable foam possesses when it exists in porous media. Unfortunately, oil has a major destabilizing effect on foam. Therefore, it is important for EOR applications to understand how oil destroys foam. Studies all indicate that stabilization of the pseudoemulsion film is critical to maintain foam stability in the presence of oil. Hence, to aid in design of surfactant formulations for foam insensitivity to oil the authors pursue direct measurement of the thin-film or disjoining forces that stabilize pseudoemulsion films. Experimental procedures and preliminary results are described.
Date: June 1, 1991
Creator: Bergeron, V. & Radke, C. J.
System: The UNT Digital Library
Summary of the presentations at the international workshop on reducing carbon dioxide emissions from the developing world: Assessment of benefits, costs and barriers (open access)

Summary of the presentations at the international workshop on reducing carbon dioxide emissions from the developing world: Assessment of benefits, costs and barriers

The ``International Workshop on Reducing Carbon Dioxide Emissions from the Developing World: Assessment of Benefits, Costs and Barriers`` was the second workshop held as part of a project being conducted by the International Energy Studies Group of Lawrence Berkeley Laboratory, in collaboration with experts from leading institutions across the developing world. The goal of the project is to analyze long-range energy consumption in developing countries and its potential contribution to global climate change. The US Environmental Protection Agency (EPA) is supporting this work, the results of which already have made a key contribution to the technical analysis being used as the basis for discussion by the Energy and Industry Sub-group of the Intergovernmental Panel on Climate Change (IPCC). The main purpose of this workshop was two-fold: (1) to discuss the feasibility of implementing the efficiency improvements and fuel switching measures incorporated into the long-term energy scenarios created for 17 developing countries and (2) to examine the costs and benefits of reducing energy-related carbon dioxide emissions generated by developing countries.
Date: June 1, 1991
Creator: Sathaye, J. & Goldman, N.
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.
System: The UNT Digital Library
What controls phytoplankton production in nutrient-rich areas of the open sea? (open access)

What controls phytoplankton production in nutrient-rich areas of the open sea?

The oceans play a critical role in regulating the global carbon cycle. Deep-ocean waters are roughly 200% supersaturated with CO{sub 2} compared to surface waters, which are in contact with the atmosphere. This difference is due to the flux of photosynthetically derived organic material from surface to deep waters and its subsequent remineralization, i.e. the ``biological pump``. The pump is a complex phytoplankton-based ecosystem. the paradoxical nature of ocean regions containing high nutrients and low phytoplankton populations has intrigued biological oceanographers for many years. Hypotheses to explain the paradox include the regulation of productivity by light, temperature, zooplankton grazing, and trace metal limitation and/or toxicity. To date, none of the hypotheses, or combinations thereof, has emerged as a widely accepted explanation for why the nitrogen and phosphorus are not depleted in these regions of the oceans. Recently, new evidence has emerged which supports the hypothesis that iron limitation regulates primary production in these areas. This has stimulated discussions of the feasibility of fertilizing parts the Southern Ocean with iron, and thus sequestering additional atmospheric CO{sub 2} in the deep oceans, where it would remain over the next few centuries. The economic, social, and ethical concerns surrounding such a proposition, along …
Date: June 25, 1991
Creator: Weiler, C. S.
System: The UNT Digital Library
Commercial applications of perfluorocarbon tracer (PFT) technology. Revision (open access)

Commercial applications of perfluorocarbon tracer (PFT) technology. Revision

Tracer technology can be successfully applied to many leak-checking and monitoring evaluations of operating systems (e.g., building HVACs), manufacturing processes and products (e.g., air conditioners), and subsurface components and systems (e.g., underground storage tanks). Perfluorocarbon tracer (PFT) technology is the most sensitive of all tracer technologies because the ambient background levels of the five (5) routinely-used PFTs are in the range of parts per 10{sup 15} parts of air (i.e., parts per quadrillion-ppq) and this technology`s instrumentation can measure down to those levels. The effectiveness of this technology is achieved both in terms of cost (very little PFT need to be used) and detectability; for example, very small leaks can be rapidly detected. The PFT compounds, which are environmentally and biologically safe to use, are commercially available as are the sampling and analysis instrumentation. This presentation concerns (1) the steps being taken to commercialize this technology, (2) new applications of processes currently under study, and (3) applications in areas of use that will be particularly beneficial to the environment. 21 refs., 2 figs., 2 tabs.
Date: June 1, 1991
Creator: Dietz, R. N.
System: The UNT Digital Library
A Computer-Based Building Design Support Environment (open access)

A Computer-Based Building Design Support Environment

Continuously decreasing cost has brought computers into most architectural and engineering offices, most commonly for activities such as drafting, accounting and word processing. Computers are used less often to predict the performance of design solutions. However, most performance simulation software packages are simplified versions of main-frame analytical tools, originally developed for research. Such software packages focus on specific design issues according to the research needs. Also, the data input requirements are complicated and incompatible with each other, and the output data are usually specialized and difficult to interpret. It is yet to be seen how the increasing memory and processing speed of computers, the two main advantages that computers have over the human brain, can be used to assist designers throughout the design process, allowing them to organize design projects electronically. We describe the design and initial implementation of a computer-based Building Design Support Environment whose structure and operation are derived from a detailed theoretical analysis of the design process, into the iterative and interactive activities that contribute towards the formulation of design criteria, the generation of potential solutions, and their evaluation. The identified design activities are characterized with respect to the nature of knowledge requirements and the degree to …
Date: June 1, 1991
Creator: Papamichael, K. & Selkowitz, S. E.
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.
System: The UNT Digital Library
Proceedings of the third annual fuel cells contractors review meeting (open access)

Proceedings of the third annual fuel cells contractors review meeting

The overall objective of this program is to develop the essential technology for private sector characterization of the various fuel cell electrical generation systems. These systems promise high fuel to electricity efficiencies (40 to 60 percent), distinct possibilities for cogeneration applications, modularity of design, possibilities of urban siting, and environmentally benign emissions. The purpose of this meeting was to provide the research and development (R D) participants in the DOE/Fossil Energy-sponsored Fuel Cells Program with the opportunity to present key results of their research and to establish closer business contacts. Major emphasis was on phosphoric acid, molten carbonate, and solid oxide technology efforts. Research results of the coal gasification and gas stream cleanup R D activities pertinent to the Fuel Cells Program were also highlighted. Two hundred seventeen attendees from industry, utilities, academia, and Government participated in this 2-day meeting. Twenty-three papers were given in three formal sessions: molten carbonate fuel cells R D (9 papers), solid oxide fuel cells (8 papers), phosphoric acid fuel cells R D (6 papers). In addition to the papers and presentations, these proceedings also include comments on the Fuel Cells Program from the viewpoint of DOE/METC Fuel Cell Overview by Rita A. Bajura, DOE/METC …
Date: June 1, 1991
Creator: Huber, W.J. (ed.)
System: The UNT Digital Library
Modulator considerations for beam chopping in the low energy beam transport at the SSC Laboratory (open access)

Modulator considerations for beam chopping in the low energy beam transport at the SSC Laboratory

Beam chopping in the low energy transport line at the Superconducting Super Collider Laboratory is accomplished using an electrostatic deflection system. LINAC requirements dictate the design of two modulators operating at 10 Hz with rise and fall times (as measured from approximately 10--99%) of {approximately}100 ns. Design of the first pulser, normally at 10 kV and pulsed to ground potential, utilizes a transformer-coupled diode-clamped solid state circuit to achieve the 2--35 {mu}s pulse width range required. The second pulser, which pulses from ground to approximately 7 kV, relies on a series vacuum tube circuit. The current designs, as well as recent test results and other circuit topologies considered, will be presented. 6 refs.
Date: June 1, 1991
Creator: Anderson, D. & Pappas, G.
System: The UNT Digital Library
Laboratory Performance of a Dynamic Ice Storage System (open access)

Laboratory Performance of a Dynamic Ice Storage System

The performance of a commercial 30-ton dynamic ice storage system was measured in a dedicated laboratory test facility and the results analyzed. The ice storage system was tested over a wide range of operating conditions to characterize the ice generating performance as a function of condensing conditions, ice build time, and defrost time. The overall efficiency of ice production was determined and the effect of refrigeration system component performance on the overall system efficiency was evaluated. The ability of the charged system -- a tank of ice slush -- to meet a simulated cooling load over was also evaluated. 18 refs., 9 figs.
Date: June 1, 1991
Creator: Stovall, T. K. & Tomlinson, J. J.
System: The UNT Digital Library
A. C. losses in the SSC high energy booster dipole magnets (open access)

A. C. losses in the SSC high energy booster dipole magnets

The baseline design for the SSC High Energy Booster (HEB) has dipole bending magnets with a 50 mm aperture. An analysis of the cryogenic heat load due to A.C. losses generated in the HEB ramp cycle are reported for this magnet. Included in this analysis are losses from superconductor hysteresis, yoke hysteresis, strand eddy currents, and cable eddy currents. The A.C. loss impact of 2.5 {mu}m vs. 6 {mu}m filament conductor is presented. A 60 mm aperture design is also investigated. 8 refs., 3 tabs.
Date: June 1, 1991
Creator: Jayakumar, R.; Kovachev, V.; Snitchler, G. & Orrell, D.
System: The UNT Digital Library
Abstracts and research accomplishments of university coal research projects (open access)

Abstracts and research accomplishments of university coal research projects

The Principal Investigators of the grants supported by the University Coal Research Program were requested to submit abstracts and highlight accomplishments of their projects in time for distribution at a grantees conference. This book is a compilation of the material received in response to the request. Abstracts discuss the following area: coal science, coal surface science, reaction chemistry, advanced process concepts, engineering fundamentals and thermodynamics, environmental science.
Date: June 1, 1991
Creator: unknown
System: The UNT Digital Library
Comparative yield estimation via shock hydrodynamic methods (open access)

Comparative yield estimation via shock hydrodynamic methods

Shock TOA (CORRTEX) from recent underground nuclear explosions in saturated tuff were used to estimate yield via the simulated explosion-scaling method. The sensitivity of the derived yield to uncertainties in the measured shock Hugoniot, release adiabats, and gas porosity is the main focus of this paper. In this method for determining yield, we assume a point-source explosion in an infinite homogeneous material. The rock is formulated using laboratory experiments on core samples, taken prior to the explosion. Results show that increasing gas porosity from 0% to 2% causes a 15% increase in yield per ms/kt{sup 1/3}. 6 refs., 4 figs.
Date: June 1, 1991
Creator: Attia, A. V.; Moran, B. & Glenn, L. A.
System: The UNT Digital Library
Versatile high current metal ion implantation facility (open access)

Versatile high current metal ion implantation facility

A metal ion implantation facility has been developed with which high current beams of practically all the solid metals of the periodic table can be produced. A multi-cathode, broad beam, metal vapor vacuum arc ion source is used to produce repetitively pulsed metal ion beams at an extraction voltage of up to 100 kV, corresponding to an ion energy of up to several hundred keV because of the ion-charge state multiplicity, and with a beam current of up to several amperes peak pulsed and several tens of mA time averaged delivered onto a downstream target. Implantation is done in a broad-beam mode, with a direct line-of-sight from ion source to target. Here we summarize some of the features of the ion source and the implantation facility that has been built up around it. 28 refs., 5 figs.
Date: June 1, 1991
Creator: Brown, I.G.; Dickinson, M.R.; Galvin, J.E.; Godechot, X. & MacGill, R.A.
System: The UNT Digital Library
Commercial applications of perfluorocarbon tracer (PFT) technology (open access)

Commercial applications of perfluorocarbon tracer (PFT) technology

Tracer technology can be successfully applied to many leak-checking and monitoring evaluations of operating systems (e.g., building HVACs), manufacturing processes and products (e.g., air conditioners), and subsurface components and systems (e.g., underground storage tanks). Perfluorocarbon tracer (PFT) technology is the most sensitive of all tracer technologies because the ambient background levels of the five (5) routinely-used PFTs are in the range of parts per 10{sup 15} parts of air (i.e., parts per quadrillion-ppq) and this technology's instrumentation can measure down to those levels. The effectiveness of this technology is achieved both in terms of cost (very little PFT need to be used) and detectability; for example, very small leaks can be rapidly detected. The PFT compounds, which are environmentally and biologically safe to use, are commercially available as are the sampling and analysis instrumentation. This presentation concerns (1) the steps being taken to commercialize this technology, (2) new applications of processes currently under study, and (3) applications in areas of use that will be particularly beneficial to the environment. 21 refs., 2 figs., 2 tabs.
Date: June 1, 1991
Creator: Dietz, R. N.
System: The UNT Digital Library
Summary of the presentations at the international workshop on reducing carbon dioxide emissions from the developing world: Assessment of benefits, costs and barriers (open access)

Summary of the presentations at the international workshop on reducing carbon dioxide emissions from the developing world: Assessment of benefits, costs and barriers

The International Workshop on Reducing Carbon Dioxide Emissions from the Developing World: Assessment of Benefits, Costs and Barriers'' was the second workshop held as part of a project being conducted by the International Energy Studies Group of Lawrence Berkeley Laboratory, in collaboration with experts from leading institutions across the developing world. The goal of the project is to analyze long-range energy consumption in developing countries and its potential contribution to global climate change. The US Environmental Protection Agency (EPA) is supporting this work, the results of which already have made a key contribution to the technical analysis being used as the basis for discussion by the Energy and Industry Sub-group of the Intergovernmental Panel on Climate Change (IPCC). The main purpose of this workshop was two-fold: (1) to discuss the feasibility of implementing the efficiency improvements and fuel switching measures incorporated into the long-term energy scenarios created for 17 developing countries and (2) to examine the costs and benefits of reducing energy-related carbon dioxide emissions generated by developing countries.
Date: June 1, 1991
Creator: Sathaye, J. & Goldman, N.
System: The UNT Digital Library
Connections between magnetism and superconductivity in UBe13 doped with thorium or boron (open access)

Connections between magnetism and superconductivity in UBe13 doped with thorium or boron

Magnetism and superconductivity appear to be intimately connected in the heavy electron (HE) superconductors. For example, it has been conjectured but not proven that the exchange of antiferromagnetic spin fluctuations are responsible for pairing in HE superconductors. In this paper we review recent results in U{sub 1-x}Th{sub x}Be{sub 13}, where specific heat, lower critical field and zero-field {mu}SR measurements reveal another second-order phase transition to a state which possesses small-moment magnetic correlations for 0.019 {le} {times} {le} 0.043. We present a new phase diagram for (U,Th)Be{sub 13} which indicates that the superconducting and magnetic order parameters are closely coupled. A discussion of the nature of the lower phase is presented, including the consideration of a possible magnetic superconducting state. When UBe{sub 13} is doped with B (UBe{sub 12.97}B{sub 0.03}) the Kondo temperature is decreased and the specific heat jump at the superconducting transition temperature is significantly enhanced. However, {mu}SR measurements reveal no magnetic signature in UBe{sub 12.97}B{sub 0.03}, unlike the case for Th doping. The correlation between changes in the Kondo temperature and changes in the superconducting properties induced by B doping provide evidence for the importance of magnetic excitations in the superconducting pairing interaction in UBe{sub 13}.
Date: June 1, 1991
Creator: Heffner, R.H.; Ott, H.R.; Schenck, A.; Mydosh, J.A. & MacLaughlin, D.E. (Los Alamos National Lab., NM (USA))
System: The UNT Digital Library
Investigation of a hamiltonian with two sources of anisotropy: The dzyaloshinskii-moriya and single-size interactions (open access)

Investigation of a hamiltonian with two sources of anisotropy: The dzyaloshinskii-moriya and single-size interactions

La{sub 2}CuO{sub 4} is an S = 1/2 system with almost tetragonal symmetry so that there is no single site interaction term giving rise to anisotropy and the magnetic anisotropy of the system can be explained in terms of the Dzyaloshinskii-Moriya interaction. The Dzyaloshinskii-Moriya interaction can lead to weak ferromagnetism even in a system with predominantly antiferromagnetic interactions. However the closely related compounds, La{sub 2}NiO{sub 4} and La{sub 2}CoO{sub 4} are S = 1 and S = 3/2 systems respectively so that a single-site interaction term is present and it is of interest to see how this interaction changes the magnetic properties of these compounds. Here the classical magnetic ground states are calculated for model Hamiltonians, appropriate to the different low temperature structural phases of the compounds, containing both interactions. 15 refs., 3 figs.
Date: June 1, 1991
Creator: Coffey, D.
System: The UNT Digital Library