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Static magnetic fields: A summary of biological interactions, potential health effects, and exposure guidelines (open access)

Static magnetic fields: A summary of biological interactions, potential health effects, and exposure guidelines

Interest in the mechanisms of interaction and the biological effects of static magnetic fields has increased significantly during the past two decades as a result of the growing number of applications of these fields in research, industry and medicine. A major stimulus for research on the bioeffects of static magnetic fields has been the effort to develop new technologies for energy production and storage that utilize intense magnetic fields (e.g., thermonuclear fusion reactors and superconducting magnet energy storage devices). Interest in the possible biological interactions and health effects of static magnetic fields has also been increased as a result of recent developments in magnetic levitation as a mode of public transportation. In addition, the rapid emergence of magnetic resonance imaging as a new clinical diagnostic procedure has, in recent years, provided a strong rationale for defining the possible biological effects of magnetic fields with high flux densities. In this review, the principal interaction mechanisms of static magnetic fields will be described, and a summary will be given of the present state of knowledge of the biological, environmental, and human health effects of these fields.
Date: May 1, 1992
Creator: Tenforde, T.S.
Object Type: Article
System: The UNT Digital Library
International research into chlorofluorocarbon (CFC) alternatives (open access)

International research into chlorofluorocarbon (CFC) alternatives

Selected researchers from 21 countries were queried through questionnaires about their current and planned research activities. The results of the survey show that the majority of research being conducted by the respondents is devoted to investigating the hydrogenated fluorocarbon HFC-134a as a replacement for CFC-12 in refrigeration applications. The main issue with this alternative is identifying compatible lubricants that do not reduce its effectiveness.
Date: May 1, 1992
Creator: Marseille, T. J.; Shankle, D. L. & Thurman, A. G.
Object Type: Report
System: The UNT Digital Library
(Experimental physics at Yale University: Research proposal and budget Proposal, 1 January 1992--31 December 1996) (open access)

(Experimental physics at Yale University: Research proposal and budget Proposal, 1 January 1992--31 December 1996)

This report reviews the following topics: nuclear and quark matter; correlated pairs from heavy ion collisions-search for new low mass resonances coupled to electron-positron collisions; proposed light ion research program; experimental nuclear astrophysics (explosive nucleosynthesis); search for rare decay modes and rare processes in nuclei; and nuclear spectroscopy at the extremes of spin, isospin, and temperature. (LSP).
Date: January 1, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Frequency-domain stress prediction algorithm for the LIFE2 fatigue analysis code (open access)

Frequency-domain stress prediction algorithm for the LIFE2 fatigue analysis code

The LIFE2 computer code is a fatigue/fracture analysis code that is specialized to the analysis of wind turbine components. The numerical formulation of the code uses a series of cycle mount matrices to describe the cyclic stress states imposed upon the turbine. However, many structural analysis techniques yield frequency-domain stress spectra and a large body of experimental loads (stress) data is reported in the frequency domain. To permit the analysis of this class of data, a Fourier analysis module has been added to the code. The module transforms the frequency spectrum to an equivalent time series suitable for rainflow counting by other modules in the code. This paper describes the algorithms incorporated into the code and uses experimental data to illustrate their use. 10 refs., 11 figs.
Date: January 1, 1992
Creator: Sutherland, H. J.
Object Type: Article
System: The UNT Digital Library
Impact of Nonequilibrium Particle Temperature Considerations on Seeded Coal Combustion Plasma Properties (open access)

Impact of Nonequilibrium Particle Temperature Considerations on Seeded Coal Combustion Plasma Properties

The first of the three tasks of this research activity is to develop a model that represents steady, nonequilibrium energy interactions between post-combustion entrained particles and carrier gases, under typical coal-fired MHD operating conditions. The second task is to use the developed model to evaluate, for both the MHD linear channel and disk configurations. the impact of nonequilibrium particle temperatures on predicted gasdynamic and electrical property values that depend, at times critically, on plasma temperatures, and on which the overall MHD system performance depends. The third task is to evaluate the relative impact of gas-particle temperature differences on generator slag phenomena and consequently on MHD channel performance.
Date: January 1, 1992
Creator: Oni, A. A.
Object Type: Report
System: The UNT Digital Library
Superconducting final focus for the SLAC Linear Collider (open access)

Superconducting final focus for the SLAC Linear Collider

Triplets composed of superconducting quadrupoles have been built and installed as the final focusing element for the high-energy positron and electron beams of the SLAC Linear Collider. Special features include independent alignment to 100-micron tolerance inside a common cryostat; non-magnetic materials to allow operation inside the detector's solenoid field; a continuous-flow helium-only system using 50-meter-long flexible transfer lines; and complete operation of the system before installation. The mechanical design and cryogenic operation experience are presented.
Date: May 1, 1992
Creator: Ash, W.W.; Barrera, F.; Burgess, W.; Cook, K.; Cutler, H.; Ferrie, J. et al.
Object Type: Article
System: The UNT Digital Library
Radioactive waste management in the former USSR (open access)

Radioactive waste management in the former USSR

Radioactive waste materials--and the methods being used to treat, process, store, transport, and dispose of them--have come under increased scrutiny over last decade, both nationally and internationally. Nuclear waste practices in the former Soviet Union, arguably the world's largest nuclear waste management system, are of obvious interest and may affect practices in other countries. In addition, poor waste management practices are causing increasing technical, political, and economic problems for the Soviet Union, and this will undoubtedly influence future strategies. this report was prepared as part of a continuing effort to gain a better understanding of the radioactive waste management program in the former Soviet Union. the scope of this study covers all publicly known radioactive waste management activities in the former Soviet Union as of April 1992, and is based on a review of a wide variety of literature sources, including documents, meeting presentations, and data base searches of worldwide press releases. The study focuses primarily on nuclear waste management activities in the former Soviet Union, but relevant background information on nuclear reactors is also provided in appendixes.
Date: June 1, 1992
Creator: Bradley, D.J.
Object Type: Report
System: The UNT Digital Library
Defense waste processing facility startup progress report (open access)

Defense waste processing facility startup progress report

The Savannah River Site (SRS) has been operating a nuclear fuel cycle since the 1950's to produce nuclear materials in support of the national defense effort. About 83 million gallons of high level waste produced since operation began have been consolidated into 33 million gallons by evaporation at the waste tank farm. The Department of Energy has authorized the construction of the Defense Waste Processing Facility (DWPF) to immobilize the waste as a durable borosilicate glass contained in stainless steel canisters, prior to emplacement in a federal repository. The DWPF is now mechanically complete and undergoing commissioning and run-in activities. Cold startup testing using simulated non-radioactive feeds is scheduled to begin in November 1992 with radioactive operation scheduled to begin in May 1994. While technical issues have been identified which can potentially affect DWPF operation, they are not expected to negatively impact the start of non-radioactive startup testing.
Date: January 1, 1992
Creator: Iverson, D.C. & Elder, H.H.
Object Type: Article
System: The UNT Digital Library
Sandia software guidelines, Volume 4: Configuration management (open access)

Sandia software guidelines, Volume 4: Configuration management

This volume is one in a series of Sandia Software Guidelines for use in producing quality software within Sandia National Laboratories. This volume is based on the IEEE standard and guide for software configuration management. The basic concepts and detailed guidance on implementation of these concepts are discussed for several software project types. Example planning documents for both projects and organizations are included.
Date: June 1, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Krakow Clean Fossil Fuels and Energy Efficiency Project (open access)

Krakow Clean Fossil Fuels and Energy Efficiency Project

In Karkow, Poland almost half of the energy used for heating is supplied by local, solid-fuel-fired boilerhouses and home stoves. These facilities are referred to as the low emission sources'' and are primary contributors of particulates and hydrocarbon air pollution in the city and secondary contributors of sulfur dioxide and carbon monoxide. The Support of Eastern European Democracy Act of 1989 directed the US Department of Energy to undertake an equipment assessment project aimed at developing the capability within Poland to manufacture or modify industrial-scale combustion equipment to utilize fossil fuels cleanly. The Project is being conducted in a manner that can be generalized to all of Poland and uito the rest of Eastern Europe. The project plan includes three phases which have been developed around five specific subprojects. In Phase 1, technical and economic assessments will be made of pollution reduction options for the five subprojects. Phase 2 plans call for public meetings in the US and Poland for companies interested in forming joint ventures. Information will be available in these meetings to enable companies to identify markets and select potential partners that meet with their capabilities and interests. In Phase 3, DOE will issue a solicitation for Polish/American …
Date: May 1, 1992
Creator: Butcher, T.A.; Pierce, B.; Krajewski, R.; LaMontagne, J. & Kirchstetter, T.
Object Type: Article
System: The UNT Digital Library
Acceleration of electrons using an inverse free electron laser auto- accelerator (open access)

Acceleration of electrons using an inverse free electron laser auto- accelerator

We present data from our study of a device known as the inverse free electron laser. First, numerical simulations were performed to optimize the design parameters for an experiment that accelerates electrons in the presence of an undulator by stimulated absorption of radiation. The Columbia free electron laser (FEL) was configured as an auto-accelerator (IFELA) system; high power (MW's) FEL radiation at {approximately}1.65 mm is developed along the first section of an undulator inside a quasi-optical resonator. The electron beam then traverses a second section of undulator where a fraction of the electrons is accelerated by stimulated absorption of the 1.65 mm wavelength power developed in the first undulator section. The second undulator section has very low gain and does not generate power on its own. We have found that as much as 60% of the power generated in the first section can be absorbed in the second section, providing that the initial electron energy is chosen correctly with respect to the parameters chosen for the first and second undulators. An electron momentum spectrometer is used to monitor the distribution of electron energies as the electrons exit the IFELA. We have found; using our experimental parameters, that roughly 10% of …
Date: July 1, 1992
Creator: Wernick, I.K. & Marshall, T.C.
Object Type: Report
System: The UNT Digital Library
Validation issues in aging risk evaluations (open access)

Validation issues in aging risk evaluations

Validation issues in aging risk evaluations are examined by considering how variabilities and uncertainties due to sparse component aging data, modeling assumptions, and risk quantification approaches may affect aging risk evaluation results and inferences. Sensitivity studies using a NUREG-1150 PWR evaluated the effect of component aging data uncertainties and variations in test and maintenance frequencies on aging prioritizations. Preliminary results indicate that while individual component rankings may be sensitive to aging data uncertainties, the top contributors as a group are not easily affected. Aging prioritizations seem to be quite sensitive to component test and maintenance frequencies. The results of the sensitivity study will help identify prioritization schemes which are robust and meaningful for applications.
Date: January 1, 1992
Creator: Hassan, M.; Samanta, P. (Brookhaven National Lab., Upton, NY (United States)) & Vesely, W. (Science Applications International Corp., San Diego, CA (United States))
Object Type: Article
System: The UNT Digital Library
Electric-utility DSM programs: 1990 data and forecasts to 2000 (open access)

Electric-utility DSM programs: 1990 data and forecasts to 2000

In April 1992, the Energy Information Administration (EIA) released data on 1989 and 1990 electric-utility demand-site management (DMS) programs. These data represent a census of US utility DSM programs, with reports of utility expenditures, energy savings, and load reductions caused by these programs. In addition, EIA published utility estimates of the costs and effects of these programs from 1991 to 2000. These data provide the first comprehensive picture of what utilities are spending and accomplishing by utility, state, and region. This report presents, summarizes, and interprets the 1990 data and the utility forecasts of their DSM-program expenditures and impacts to the year 2000. Only utilities with annual sales greater than 120 GWh were required to report data on their DSM programs to EIA. Of the 1194 such utilities, 363 reported having a DSM program that year. These 363 electric utilities spent $1.2 billion on their DSM programs in 1990, up from $0.9 billion in 1989. Estimates of energy savings (17,100 GWh in 1990 and 14,800 GWh in 1989) and potential reductions in peak demand (24,400 MW in 1990 and about 19,400 MW in 1989) also showed substantial increases. Overall, utility DSM expenditures accounted for 0.7% of total US electric revenues, …
Date: June 1, 1992
Creator: Hirst, E.
Object Type: Report
System: The UNT Digital Library
Optimization of a VISAR for measuring flyer-plate velocities (open access)

Optimization of a VISAR for measuring flyer-plate velocities

VISAR (Velocity Interferometer System for Any Reflector) is commonly used for measuring flyer-plate velocities up to 6 km/s. Flyer plates can travel as much as 1 mm, which is large compared to usual depth-of-focus requirements for VISARs. Flyer plates are explosively driven, or driven by some other very energetic means; as such, they must be tested in a chamber, which will contain the explosion. Routing the laser beam to the chamber and the signal beam to the VISAR can be done safely and easily in multi-mode optical fibers. We have optimized a fiber-coupled VISAR system for measuring flyer-plate velocities. This system given constant signal levels over the full travel of the flyer plate. Furthermore, the signal-collection efficiency is maximized, which allows use of a moderately sized laser. We also have optimized the VISAR cavity so it does not limit the system efficiency while giving a velocity sensitivity of about 1 km/s per fringe. 5 refs.
Date: May 6, 1992
Creator: Sweatt, W. C.; Crump, O. B., Jr. & Brigham, W. P.
Object Type: Article
System: The UNT Digital Library
Reviewing the impact of advanced control room technology (open access)

Reviewing the impact of advanced control room technology

Progress to date on assessing the nature of the expected changes in human performance and risk associated with the introduction of digital control, instrumentation, and display systems is presented. Expected changes include the shift toward more supervisory tasks, development of intervention strategies, and reallocation of function between human and machine. Results are reported in terms of the scope of new technology, human performance issues, and crews experience with digital control systems in a variety of industries petrochemical and aerospace. Plans to conduct a limited Probabilistic Risk Assessment/Human Reliability Assessment (PRA/HRA) comparison between a conventional NUREG-1150 series plant and that same plant retrofit with distributed control and advanced instrumentation and display are also presented. Changes needed to supplement existing HRA modeling methods and quantification techniques are discussed.
Date: January 1, 1992
Creator: Wilhelmsen, C. A.; Gertman, D. I.; Ostrom, L. T.; Nelson, W. R.; Galyean, W. J. & Byers, J. C.
Object Type: Article
System: The UNT Digital Library
A review of proposed Glen Canyon Dam interim operating criteria (open access)

A review of proposed Glen Canyon Dam interim operating criteria

Three sets of interim operating criteria for Glen Canyon Dam on the Colorado River have been proposed for the period of November 1991, to the completion of the record of decision for the Glen Canyon Dam environmental impact statement (about 1993). These criteria set specific limits on dam releases, including maximum and minimum flows, up-ramp and down-ramp rates, and maximum daily fluctuation. Under the proposed interim criteria, all of these parameters would be reduced relative to historical operating criteria to protect downstream natural resources, including sediment deposits, threatened and endangered fishes, trout, the aquatic food base, and riparian plant communities. The scientific bases of the three sets of proposed operating criteria are evaluated in the present report:(1) criteria proposed by the Research/Scientific Group, associated with the Glen Canyon Environmental Studies (GCES); (2) criteria proposed state and federal officials charged with managing downstream resources; and (3) test criteria imposed from July 1991, to November 1991. Data from Phase 1 of the GCES and other sources established that the targeted natural resources are affected by dam operations, but the specific interim criteria chosen were not supported by any existing studies. It is unlikely that irreversible changes to any of the resources would …
Date: April 1, 1992
Creator: LaGory, K.; Hlohowskyj, I.; Tomasko, D.; Hayse, J. & Durham, L.
Object Type: Report
System: The UNT Digital Library
Research on elementary particle physics: Task P, Studies in theory and phenomenology of elementary particles (open access)

Research on elementary particle physics: Task P, Studies in theory and phenomenology of elementary particles

Over the last year, work has focused on two areas: the phenomenology of quark-gluon differentiation in jets, and theoretical studies involving Dirac-like equations for various systems. Substantive progress has been made in both areas. A paper comparing details of the Lund and Herwig simulations for quark and gluon jets has been written and accepted by Physical Review D. A paper describing a new type of Dirac equation for the relativistic harmonic oscillator, and finding solutions thereof, has been written and submitted for publication.
Date: May 1, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Tandems as injectors for synchrotrons (open access)

Tandems as injectors for synchrotrons

This is a review on the use of Tandem electrostatic accelerators for injection and filling of synchrotrons to accelerate intense beams of heavy-ions to relativistic energies. The paper emphasizes the need of operating the Tandems in pulsed mode for this application. It has been experimentally demonstrated that at the present this type of accelerators still provides the most reliable and best performance.
Date: January 1, 1992
Creator: Ruggiero, Alessandro G.
Object Type: Article
System: The UNT Digital Library
Electronic and structural properties of metallic microclusters (open access)

Electronic and structural properties of metallic microclusters

The first part of this thesis presents a first-order pseudopotential calculation at T=O of the total energy of small sodium clusters of size N<800. The calculation is based on a local-pseudopotential scheme and local-density correlation and exchange. A temperature-size (T-N) phase-diagram is then derived using the T=O results and Lindemann's criterion for melting. The phase-diagram contains three regions of stability: (1) a liquid (jellium) phase at temperatures above the melting line T{sub M}(N) where cluster-stability occurs at electronic magic numbers: (2) a phase related to complete geometrical shells of body-centered-cubic structure at temperatures below the melting line; and (3) a close-packed structure at very low temperatures and sufficiently large N. The melting line drops to T{sub M}(N)=O for N<65, where electronic magic numbers are stable even at T=O. The phase diagram reduces asymptotically to the known phases of sodium as N{yields}{infinity}, including the known martensitic transformation at T{approximately}5 K. The second and the last part of this thesis consists of a study of small-cluster many-body systems by means of an on-site local'' chemical potential which allows the continuous variation of local electron-density. This method yields a criterion to distinguish particular features of a small cluster that are likely to survive …
Date: April 1, 1992
Creator: Maiti, A.
Object Type: Report
System: The UNT Digital Library
(Gamma scattering in condensed matter with high intensity Moessbauer radiation) (open access)

(Gamma scattering in condensed matter with high intensity Moessbauer radiation)

This report discusses: quasielastic scattering studies on glycerol; gamma-ray scattering from alkali halides; lattice dynamics in metals; Moessbauer neutron scattering, x-ray diffraction, and macroscopic studies of high {Tc} superconductors containing tungsten; NiAl scattering studies; and atomic interference factors and nuclear Casimir effect.
Date: January 1, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Particulate behavior in a controlled-profile pulverized coal-fired reactor: A study of coupled turbulent particle dispersion and thermal radiation transport (open access)

Particulate behavior in a controlled-profile pulverized coal-fired reactor: A study of coupled turbulent particle dispersion and thermal radiation transport

This report describes recent progress in a fundamental, three-year investigation of the coupled problem of turbulent particle dispersion and thermal radiation transport. The project's objective is to make measurements of particle size, velocity, number density, temperature and wall radiant heat flux in a parametrically-controlled reactor presently existent at Brigham Young University (BYU). Although the study proposed here is primarily designed to provide experimental data not currently available for the evaluation of turbulent particle dispersion and radiation models, comparisons of analytical predictions and the experimental data obtained will be performed, using appropriate submodels integral to comprehensive pulverized-coal combustion codes existent at BYU.
Date: January 1, 1992
Creator: Queiroz, M. & Webb, B.W.
Object Type: Report
System: The UNT Digital Library
On-line chemical composition analyzer development (open access)

On-line chemical composition analyzer development

The energy consumed in distillation processes in the United States represents nearly three percent of the total national energy consumption. If effective control of distillation columns can be accomplished, it has been estimated that it would result in a reduction in the national energy consumption of 0.3%. Real-time control based on mixture composition could achieve these savings. However, the major distillation processes represent diverse applications and at present there does not exist a proven on-line chemical composition sensor technology which can be used to control these diverse processes in real-time. This report presents a summary of the findings of the second phase of a three phase effort undertaken to develop an on-line real-time measurement and control system utilizing Raman spectroscopy. A prototype instrument system has been constructed utilizing a Perkin Elmer 1700 Spectrometer, a diode pumped YAG laser, two three axis positioning systems, a process sample cell land a personal computer. This system has been successfully tested using industrially supplied process samples to establish its performance. Also, continued application development was undertaken during this Phase of the program using both the spontaneous Raman and Surface-enhanced Raman modes of operation. The study was performed for the US Department of Energy, Office …
Date: February 1, 1992
Creator: Roberts, M.J.; Garrison, A.A.; Muly, E.C. & Moore, C.F.
Object Type: Report
System: The UNT Digital Library
CGVIEW: A program to generate isometric and perspective views of combinatorial geometries (open access)

CGVIEW: A program to generate isometric and perspective views of combinatorial geometries

The prototype of a graphical debugger for combinatorial geometry (CG) is described. The prototype debugger consists of two parts: a FORTRAN-based view'' generator and a Microsoft Windows application for displaying the geometry. This document describes the code CGVIEW, which comprises the first part of the system. User-specified options permit the selection of an arbitrary viewpoint in space and the generation of either an isometric or perspective view. Additionally, any combination of zones, materials, or regions can be flagged as invisible to facilitate the inspection of internal details of the geometry. In the same manner, an arbitrary body can be cut away from the geometry to facilitate inspection and debugging. Examples illustrating the various options are described.
Date: July 1, 1992
Creator: Burns, T.J.
Object Type: Report
System: The UNT Digital Library
Fossil Energy Advanced Research and Technology Development (AR TD) Materials Program semiannual progress report for the period ending September 30, 1991 (open access)

Fossil Energy Advanced Research and Technology Development (AR TD) Materials Program semiannual progress report for the period ending September 30, 1991

The objective of the Fossil Energy Advanced Research and Technology Development Materials Program is to conduct research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The Program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. Research is outlined in four areas: Ceramics, New Alloys, Corrosion and Erosion Research, and Technology Development and Transfer. (VC)
Date: April 1, 1992
Creator: Judkins, R.R. & Cole, N.C. (comps.)
Object Type: Report
System: The UNT Digital Library