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Pilot study risk assessment for selected problems at the Nevada Test Site (NTS) (open access)

Pilot study risk assessment for selected problems at the Nevada Test Site (NTS)

The Nevada Test Site (NTS) is located in southwestern Nevada, about 105 km (65 mi) northwest of the city of Las Vegas. A series of tests was conducted in the late 1950s and early 1960s at or near the NTS to study issues involving plutonium-bearing devices. These tests resulted in the dispersal of about 5 TBq of [sup 239,24O]Pu on the surficial soils at the test locations. Additionally, underground tests of nuclear weapons devices have been conducted at the NTS since late 1962; ground water beneath the NTS has been contaminated with radionuclides produced by these tests. These two important problems have been selected for assessment. Regarding the plutonium contamination, because the residual [sup 239]Pu decays slowly (half-life of 24,110 y), these sites could represent a long-term hazard if they are not remediated and if institutional controls are lost. To investigate the magnitude of the potential health risks for this no-remediation case, three basic exposure scenarios were defined that could bring individuals in contact with [sup 239,24O]Pu at the sites: (1) a resident living in a subdivision, (2) a resident farmer, and (3) a worker at a commercial facility -- all located at a test site. The predicted cancer risks …
Date: June 1, 1993
Creator: Daniels, J.I. (ed.)
Object Type: Report
System: The UNT Digital Library
Determination of the energy of suprathermal electrons during lower hybrid current drive on PBX-M (open access)

Determination of the energy of suprathermal electrons during lower hybrid current drive on PBX-M

Suprathermal electrons are diagnosed by a hard x-ray pinhole camera during lower hybrid current drive on PBX-M. The experimental hard x-ray images are compared with simulated images, which result from an integration of the relativistic bremsstrahlung along lines-of-sight through the bean-shaped plasma. Images with centrally peaked and radially hollow radiation profiles are easily distinguished. The energy distribution of the suprathermal electrons is analyzed by comparing images taken with different absorber foils. An effective photon temperature is derived from the experimental images, and a comparison with simulated photon temperatures yields the energy of the suprathermal electrons. The analysis indicates that the energy of the suprathermal electrons in the hollow discharges is in the 50 to 100 key range in the center of the discharge. There seems to exist a very small higher energy component close to the plasma edge.
Date: June 1, 1993
Creator: Von Goeler, S.; Bernabei, S.; Davis, W.; Ignat, D.; Kaita, R.; Roney, P. et al.
Object Type: Article
System: The UNT Digital Library
Recovery and purification of nickel-63 from HFIR-irradiated targets (open access)

Recovery and purification of nickel-63 from HFIR-irradiated targets

The production of large quantities of high-specific-activity [sup 63]Ni (>10 Ci/g) requires both a highly enriched [sup 62]Ni target and a long irradiation period at high neutron flux. Trace impurities in the nickel and associated target materials are also activated and account for a significant fraction of the discharged activity and essentially all of the gamma activity. While most of these undesirable activation products can be removed as chloride complexes during anion exchange, chromium, present at [sup 51]Cr, and scandium, present as [sup 46]Sc, are exceptions and require additional processing to achieve the desired purity. Optimized flowsheets are discussed based upon the current development and production experience.
Date: June 1, 1993
Creator: Williams, D. F.; O'Kelley, G. D.; Knauer, J. B.; Porter, C. E. & Wiggins, J. T.
Object Type: Report
System: The UNT Digital Library
Pacific Northwest Laboratory Annual Report for 1992 to the DOE Office of Energy Research (open access)

Pacific Northwest Laboratory Annual Report for 1992 to the DOE Office of Energy Research

This report summarizes progress in OHER biological research and general life sciences research programs conducted at PNL in FY 1992. The research develops the knowledge and fundamental principles necessary to identify, understand, and anticipate the long-term health consequences of energy-related radiation and chemicals. Our continuing emphasis is to decrease the uncertainty of health risk estimates from energy-related technologies through an increase understanding of the ways in which radiation and chemicals cause biological damage. Descriptors of individual research projects as detailed in this report one separately abstracted and indexed for the database.
Date: June 1, 1993
Creator: Kreml, S. A. (ed.) & Park, J. F.
Object Type: Report
System: The UNT Digital Library
Computation and graphics in mathematical research (open access)

Computation and graphics in mathematical research

Current research is described on: grain boundaries and dislocations in compound polymers, boundary value problems for hypersurfaces constant Gaussian curvature, and discrete computational geometry. 19 refs, 4 figs.
Date: June 1, 1993
Creator: Hoffman, D.A. & Spruck, J.
Object Type: Report
System: The UNT Digital Library
Conical geometry for sagittal focusing as applied to X rays from synchrotrons (open access)

Conical geometry for sagittal focusing as applied to X rays from synchrotrons

The authors describe a method for simultaneously focusing and monochromatization of X rays from a fan of radiation having up to 15 mrad divergence in one dimension. This geometry is well suited to synchrotron radiation sources at magnifications of one-fifth to two and is efficient for X-ray energies between 3 and 40 keV (0.48 and 6.4 fJ). The method uses crystals bent to part of a cone for sagittal focusing and allows for the collection of a larger divergence with less mixing of the horizontal into the vertical divergence than is possible with X-ray mirrors. They describe the geometry required to achieve the highest efficiency when a conical crystal follows a flat crystal in a nondispersive two-crystal monochromator. At a magnification of one-third, the geometry is identical to a cylindrical focusing design described previously. A simple theoretical calculation is shown to agree well with ray-tracing results. Minimum aberrations are observed at magnifications near one. Applications of the conical focusing geometry to existing and future synchrotron radiation facilities are discussed.
Date: June 1, 1993
Creator: Ice, G. E. & Sparks, C. J.
Object Type: Report
System: The UNT Digital Library
Dynamic impact and pressure analysis of the insensitive munitions container PA103 with modified design features (open access)

Dynamic impact and pressure analysis of the insensitive munitions container PA103 with modified design features

This report presents analytical analyses of the insensitive munitions container PA103, with modified design features for a static internal pressure of 500 psi and for a dynamic impact resulting from a 7-ft free fall onto a rigid surface. The modified design features addressed by the analyses were the inclusion of a score pattern on the container cylindrical body and a plastic plate (fuse) sandwiched between metal flanges on the container end. The objectives of both the pressure and impact analyses were to determine if the induced stresses at the score patterns in the cylindrical body of the container were sufficient to induce failure. Analytical responses of the container to the imposed loads were obtained with finite element analysis methodology. The computer codes ABAQUS and VEC/DYNA3D were used to obtain the results. Results of the pressure analysis indicate that failure of the container body would be expected to occur at the score pattern for a static internal pressure of 500 psi. Also, results from three impact orientations for a 7-ft drop indicate that membrane stresses in the vicinity of the score pattern are above critical crack growth stress magnitudes, especially at low ([minus]60[degrees]F) temperatures.
Date: June 1, 1993
Creator: Handy, K.D.
Object Type: Report
System: The UNT Digital Library
NREL Solar Radiation Resource Assessment Project: Status and Outlook, FY 1992 Annual Progress Report (open access)

NREL Solar Radiation Resource Assessment Project: Status and Outlook, FY 1992 Annual Progress Report

This annual report summaries the activities and accomplishments of the Solar Radiation Resource Assessment Project during fiscal year 1992 (1 October to 30 September 1992). Managed by the Analytic Studies Division of the National Renewable Energy Laboratory, this project is the major activity of the US Department of Energy's Resource Assessment Program.
Date: June 1, 1993
Creator: Renne, D.; Maxwell, E.; Stoffel, T.; Marion, B.; Rymes, M.; Wilcox, S. et al.
Object Type: Report
System: The UNT Digital Library
Performance of production SRF cavities for CEBAF (open access)

Performance of production SRF cavities for CEBAF

Construction of the Continuous Electron Beam Accelerator Facility recirculating linac represents the largest scale application of superconducting rf (SRF) technology to date. Over 250 of the eventual 338 SRF 1497 MHz cavities have been assembled into hermetic pairs and completed rf testing at 2.0 K. Although the rf performance characteristics well exceed the CEBAF baseline requirements of Q[sub 0] = 2.4[times]10[sup 9] at 5 MV/m, the usual limiting phenomena are encountered field emission, quenching, Q-switching, will occasional multipacting. An analysis of the occurrence conditions and severity of these phenomena during production cavity testing is presented. The frequency with which performance is limited by quenching suggests that additional material advances may be required for applications which require the reliable achievement of accelerating gradients of more than 15 MV/m. The distributions of frequency and Q for a higher-order mode are also presented.
Date: June 1, 1993
Creator: Reece, C.; Benesch, J.; Kneisel, P.; Kushnick, P.; Mammosser, J. & Powers, T.
Object Type: Article
System: The UNT Digital Library
Macro material flow modeling for analyzing solid waste management options (open access)

Macro material flow modeling for analyzing solid waste management options

A Macro Material Flow Modeling (MMFM) concept and approach are being adopted to develop a predictive modeling capability. This capability is intended to provide part of the basis for evaluating potential impacts from various solid waste management system configurations and operating scenarios, as well as evaluating the impacts of various policies on solid waste quantities and compositions. The MMFM capability, as part of a broader Solid Waste Initiative at Pacific Northwest Laboratory, is intended to provide an increased understanding of solid waste as a disposal, energy, and resource problem on a national and global scale, particularly over the long term. This model is a macro-level simulation of the flows of the various materials through the solid waste management system, and also through the associated materials production and use system. Inclusion of materials production and use within the modeling context allows a systems approach to be used, providing a much more complete understanding of the origins of the solid waste materials and also of possible options for materials recovery and reuse than if a more traditional end-of-pipe'' view of solid waste is adopted. The MMFM is expected to be useful in evaluating longer-term, broader-ranging solid waste impacts than are traditionally evaluated …
Date: June 1, 1993
Creator: Holter, G. M.; Pennock, K. A. & Shaver, S. R.
Object Type: Article
System: The UNT Digital Library
Characterization of nanoscale oxide and oxyhydroxide powders using EXAFS spectroscopy (open access)

Characterization of nanoscale oxide and oxyhydroxide powders using EXAFS spectroscopy

Extended x-ray absorption fine structure (EXAFS) spectroscopy has been used to determine the structural environment local to iron(HI) and zircorium(IV) cations in respectively, nanoscale iron oxyhydroxide and nanoscale zirconium oxide powders. The iron oxyhydroxide powder, produced by the modified reverse micelle (MRM) technology, was found to have a short-range structure most similar to that of goethite ([alpha]-FeOOH). The short-range structure of the zirconium oxide powder, produced using the rapid thermal decomposition of solutes (RTDS) technology, was found to be a mixture of monoclinic zirconia and cubic zirconia environments.
Date: June 1, 1993
Creator: Darab, J.G.; Linehan, J.C.; Matson, D.W. (Pacific Northwest Lab., Richland, WA (United States)) & Ma, Y. (Washington Univ., Seattle, WA (United States). Dept. of Physics)
Object Type: Article
System: The UNT Digital Library
Evolution of microstructure in face centered cubic metals during irradiation: A review (open access)

Evolution of microstructure in face centered cubic metals during irradiation: A review

When fcc metals and alloys are irradiated at elevated temperatures, they tend to evolve toward saturation microstructures that are independent of the starting state of the metal and the early details of irradiation history. This leads to property changes and rates of dimensional change that also eventually become independent of the starting state. The evolution of microstructure in complex alloys, especially during the transient regime, is usually determined by the complex interaction of many microstructural and microchemical processes. The more complex the alloy, the more difficult it is to-identify and define the separate influence of each participating mechanism. The use of irradiation studies conducted on simple metals or model alloys assists in understanding the behavior of alloys of engineering relevance. A review of such studies shows that a number of prevailing perceptions of radiation-induced microstructural evolution are not universally correct.
Date: June 1, 1993
Creator: Garner, F.A.
Object Type: Article
System: The UNT Digital Library
Evaluation of potential runaway generation in large-tokamak disruptions (open access)

Evaluation of potential runaway generation in large-tokamak disruptions

A detailed evaluation of various potential mechanisms for the generation of strong runaway beams during disruptions of largetokamak devices, including TFTR, JET, DIIID and ITER, is performed based on typical operating parameters of these devices and the presently accepted disruption model. The main results include: (1) In the existing devices, the evaporative preicer'' process by itself can lead to sizable runaway beams in disruptions of high-current-medium-to-low-ne discharges. In ITER, such runaways are expected mainly for discharges with ne values sizably smaller than the projected typical ones. (2) Runaway generation also may occur during post-thermal-quench period through the untrapping of trapped hot-thermal electrons remaining from the pre-thermal-quench plasma; this process may be directly important in particular in disruptions of high-T[sub e] discharges with details depending on the time required for reclosure of the magnetic surfaces. Both processes (1) and (2) will occur and be completed mostly during the initial few 100 [mu]sec after the thermal quench. (3) Subsequently, close collisions of runaways with cold plasma electrons generally will lead to an exponential growth ( avalanching'') of runaway populations generated by processes (1) and/or (2) and/or others; this process will be effective in particular during the current quench phase and will continue …
Date: June 1, 1993
Creator: Fleischmann, H. H. & Zweben, S. J.
Object Type: Report
System: The UNT Digital Library
A comparison group analysis of DOE's Energy-Related Inventions Program (open access)

A comparison group analysis of DOE's Energy-Related Inventions Program

Over the past decade, Oak Ridge National Laboratory has conducted four evaluations of the economic impacts of the US DOE's Energy-Related Inventions Program (ERIP). None of these evaluations has involved the use of a comparison group. Instead, statistics on the innovation process have been compiled from a review of the literature. Unfortunately, the types of technologies and inventors documents by previous studies do not match those supported by the Energy-Related Inventions Program. ERIP-supported technologies are diverse in both application and technical complexity. ERIP-supported inventors are a particular subset of inventors: the Program targets inventors who are either independently employed or are employees of a small business. The purpose of this task is to identify and characterize a matched comparison group of inventors whose progress can be compared with the progress of ERIP inventors. With this comparison group, we will be able to assess more accurately the impact of the ERIP support and thereby strengthen the program's impact evaluations. This report is divided into six sections. As background to understanding the comparison group design and the results provided in this report, section 1.3 provides an overview of the Energy-Related Inventions Program. Section 2 describes the research design used to define and …
Date: June 1, 1993
Creator: Brown, M. A.; Curlee, T. R.; Elliott, S. R. & Franchuk, C. A.
Object Type: Report
System: The UNT Digital Library
The study of structure-processing-property relations in copper oxide based high [Tc] superconductors (open access)

The study of structure-processing-property relations in copper oxide based high [Tc] superconductors

Objective is investigation of critical current limiting processes in bulk superconductors. Since the grain boundaries play a key role here, we focus on the electrical characterization of single grain boundaries. Electrical contact to thin polished sections is established with thermosonic wire bonding. Laser cutting is used to isolate a single grain boundary. Results on YBa[sub 2]Cu[sub 3]O[sub x] showed that two different types of grain boundaries are present. Most grain boundaries showed current voltage characteristics typical for flux pinning effect and no or little change in low magnetic fields. However, Josephson effect could also be found in some grain boundaries exhibiting a remarkable decrease of I[sub c] in low magnetic fields. Both types could be found in the same sample. Additionally we are working on Bi[sub 2]Sr[sub 2]CaCu[sub 2]O[sub x] thick films grown on silver foil or MgO substrates. The films showed metallic behaviour and [Tc]=80K. Preliminary results showed that the grain boundaries are of the flux pinning type.
Date: June 1, 1993
Creator: Kingon, A. I.
Object Type: Report
System: The UNT Digital Library
Consolidated Research Program, United States Gulf Coast Geopressured- Geothermal Program (open access)

Consolidated Research Program, United States Gulf Coast Geopressured- Geothermal Program

Water influx calculations for the Gladys McCall reservoir were conducted based on three commonly applied water influx models. Results are shown graphically. Work on geologic studies was summarized. (MHR)
Date: June 1, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Marketing the Klamath Falls Geothermal District Heating system (open access)

Marketing the Klamath Falls Geothermal District Heating system

The new marketing strategy for the Klamath Falls system has concentrated on offering the customer an attractive and easy to understand rate structure, reduced retrofit cost and complexity for his building along with an attractive package of financing and tax credits. Initial retrofit costs and life-cycle cost analysis have been conducted on 22 buildings to date. For some, the retrofit costs are simply too high for the conversion to make sense at current geothermal rates. For many, however, the prospects are good. At this writing, two new customers are now connected and operating with 5 to 8 more buildings committed to connect this construction season after line extensions are completed. This represents nearly a 60% increase in the number of buildings connected to the system and a 40% increase in system revenue.
Date: June 1, 1993
Creator: Rafferty, K.
Object Type: Report
System: The UNT Digital Library
National Institute for Petroleum and Energy Research quarterly technical report, January 1--March 31, 1993 (open access)

National Institute for Petroleum and Energy Research quarterly technical report, January 1--March 31, 1993

Accomplishments for the past quarter are briefly described for the following tasks: chemical flooding -- supporting research; gas displacement -- supporting research; thermal recovery -- supporting research; geoscience technology; resource assessment technology; and microbial technology. Chemical flooding covers: surfactant flooding methods; development of improved alkaline flooding methods; mobility control and sweep improvement in chemical flooding; and surfactant-enhanced alkaline flooding field project. Gas displacement covers: gas flooding performance prediction improvement; and mobility control, profile modification and sweep improvement in gas flooding. Thermal recovery includes: thermal processes for light oil recovery; thermal processes for heavy oil recovery; and feasibility study of heavy oil recovery in the mid-continent region -- Oklahoma, Kansas, and Missouri; simulation analysis of steam-foam projects; and field application of foams for oil production symposium. Geoscience technology covers: three-phase relative permeability; and imaging techniques applied to the study of fluids in porous media. Resource assessment technology includes: reservoir assessment and characterization; TORIS research support; upgrade the BPO crude oil analysis data base; and compilation and analysis of outcrop data from the Muddy and Almond Formations. Microbial technology covers development of improved microbial flooding methods; and microbial-enhanced waterflooding field project.
Date: June 1, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
1990 Nationwide Truck Activity and Commodity Survey selected tabulations (open access)

1990 Nationwide Truck Activity and Commodity Survey selected tabulations

The Nationwide Truck Activity and Commodity Survey (NTACS) provides detailed activity data for a sample of trucks covered in the 1987 Truck Inventory and Use Survey (TIUS) for days selected at random over a 12-month period ending in 1990. The NTACS was conducted by the US Bureau of the Census for the US Department of Transportation (DOT). A Public Use File for the NTACS was developed by Oak Ridge National Laboratory (ORNL) under a reimbursable agreement with the DOT. The content of the Public Use File and the detailed design of the NTACS are described in the ORNL Report [open quotes]Technical Documentation for the 1990 Nationwide Truck Activity and Commodity Survey Public Use File[close quotes]. (1992). ORNL Technical Report No. TM-12188, Oak Ridge National Laboratory, Oak Ridge, TN 37831. The main purpose of this summary report is to provide selected tables based on the public use file.
Date: June 1, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Modeling of RHIC insulating vacuum for system pumpdown characteristics (open access)

Modeling of RHIC insulating vacuum for system pumpdown characteristics

This paper presents a model for predicting the pumpdown characteristics of a 480 m RHIC (Relativistic Heavy Ion Collider) vacuum cryostat. The longitudinal and transverse conductances of a typical cryostat were calculated. A voltage analogue of these conductances was constructed for room temperature conditions. The total longitudinal conductance of a room temperature cryostat was thereby achieved. This conductance was then used to calculate the diameter of an equivalent long outgassing tube, having more convenient analytical expressions for pressure profiles when pumped. The equivalent of a unit outgassing rate for this tube was obtained using previously published MLI (multi-layer insulation) outgassing data. With this model one is then able to predict a cryostat pumpdown rate as a function of the location and size of roughing pumps.
Date: June 1, 1993
Creator: Todd, R.J.; Pate, D.J. & Welch, K.M.
Object Type: Report
System: The UNT Digital Library
Sequestering carbon dioxide in industrial polymers: Building materials for the 21st century (open access)

Sequestering carbon dioxide in industrial polymers: Building materials for the 21st century

This study was undertaken to determine the possibility of developing beneficial uses for carbon dioxide as a key component for a large-volume building product. Such a use may provide an alternative to storing the gas in oceanic sinks or clathrates as a way to slow the rate of global warming. The authors investigated the concept that carbon dioxide might be used with other chemicals to make carbon-dioxide-based polymers which would be lightweight, strong, and economical alternatives to some types of wood and silica-based building materials. As a construction-grade material, carbon dioxide would be fixed in a solid, useful form where it would not contribute to global warming. With the probable imposition of a fuel carbon tax in industrialized countries, this alternative would allow beneficial use of the carbon dioxide and could remove it from the tax basis if legislation were structured appropriately. Hence, there would be an economic driver towards the use of carbon-dioxide-based polymers which would enhance their future applications. Information was obtained through literature searches and personal contacts on carbon dioxide polymers which showed that the concept (1) is technically feasible, (2) is economically defensible, and (3) has an existing industrial infrastructure which could logically develop it. The …
Date: June 1, 1993
Creator: Molton, P. M. & Nelson, D. A.
Object Type: Report
System: The UNT Digital Library
A simplified model of aerosol removal by containment sprays (open access)

A simplified model of aerosol removal by containment sprays

Spray systems in nuclear reactor containments are described. The scrubbing of aerosols from containment atmospheres by spray droplets is discussed. Uncertainties are identified in the prediction of spray performance when the sprays are used as a means for decontaminating containment atmospheres. A mechanistic model based on current knowledge of the physical phenomena involved in spray performance is developed. With this model, a quantitative uncertainty analysis of spray performance is conducted using a Monte Carlo method to sample 20 uncertain quantities related to phenomena of spray droplet behavior as well as the initial and boundary conditions expected to be associated with severe reactor accidents. Results of the uncertainty analysis are used to construct simplified expressions for spray decontamination coefficients. Two variables that affect aerosol capture by water droplets are not treated as uncertain; they are (1) [open quote]Q[close quote], spray water flux into the containment, and (2) [open quote]H[close quote], the total fall distance of spray droplets. The choice of values of these variables is left to the user since they are plant and accident specific. Also, they can usually be ascertained with some degree of certainty. The spray decontamination coefficients are found to be sufficiently dependent on the extent of …
Date: June 1, 1993
Creator: Powers, D.A. (Sandia National Labs., Albuquerque, NM (United States)) & Burson, S.B. (Nuclear Regulatory Commission, Washington, DC (United States). Div. of Safety Issue Resolution)
Object Type: Report
System: The UNT Digital Library
Colorado State University Program for Developing, Testing, Evaluating and Optimizing Solar Heating and Cooling Systems (open access)

Colorado State University Program for Developing, Testing, Evaluating and Optimizing Solar Heating and Cooling Systems

Results of heat loss tests for the Integral Collector Storage unit are shown. Work on unique solar system components is summarized briefly. (MHR)
Date: June 1, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
National Institute for Petroleum and Energy Research monthly progress report, May 1993 (open access)

National Institute for Petroleum and Energy Research monthly progress report, May 1993

Accomplishments for the month of May are described briefly under tasks for: Energy Production Research; Fuels Research; and Supplemental Government Program. Energy Production Research includes: reservoir assessment and characterization; TORIS research support; development of improved microbial flooding methods; development of improved chemical flooding methods; development of improved alkaline flooding methods; mobility control and sweep improvement in chemical flooding; gas flood performance prediction improvement; mobility control, profile modification, and sweep improvement in gas flooding; three-phase relative permeability research; thermal processes for light oil recovery; thermal processes for heavy oil recovery; and imaging techniques applied to the study of fluids in porous media. Fuels Research covers: development of analytical methodology for analysis of heavy crudes; and thermochemistry and thermophysical properties of organic nitrogen- and diheteratom-containing compounds. Supplemental Government Program covers: microbial-enhanced waterflooding field project; feasibility study of heavy oil recovery in the midcontinent region--Oklahoma, Kansas, and Missouri; surfactant-enhanced alkaline flooding field project; process-engineering property measurements on heavy petroleum components; development and application of petroleum production technologies; upgrade BPO crude oil data base; simulation analysis of steam-foam projects; DOE education initiative project; field application of foams for oil production symposium; technology transfer to independent producers; compilation and analysis of outcrop data from the …
Date: June 1, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library