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Simulations of Laser Imprint for Nova Experiments and for Ignition Capsules. Revision 1 (open access)

Simulations of Laser Imprint for Nova Experiments and for Ignition Capsules. Revision 1

In direct drive ICF, nonuniformities in laser illumination seed ripples at the ablation front in a process called ``imprint``. These nonuniformities grow during the capsule implosion and, if initially large enough, can penetrate the capsule shell, impede ignition, or degrade burn. Imprint has been simulated for recent experiments performed on the Nova laser at LLNL examining a variety of beam smoothing conditions. Most used laser intensities similar to the early part of an ignition capsule pulse shape, 1 {approx_equal} 10{sup 13} W/cm{sup 2} . The simulations matched most of the measurements of imprint modulation. The effect of imprint upon National Ignition Facility (NIF) direct drive ignition capsules has also been simulated. Imprint is predicted to give modulation comparable to an intrinsic surface finish of {approximately}10 nm RMS. Modulation growth was examined using the Haan [Phys. Rev. A {bold 39}, 5812 (1989)] model, with linear growth factors as a function of spherical harmonic mode number obtained from an analytic dispersion relation. Ablation front amplitudes are predicted to become substantially nonlinear, so that saturation corrections are large. Direct numerical simulations of two-dimensional multimode growth were also performed. The capsule shell is predicted to remain intact, which gives a basis for believing that …
Date: December 1, 1996
Creator: Weber, S. V.; Glendinning, S. G.; Kalantar, D. H.; Key, M. H.; Remington, B. A.; Rothenberg, J. L. et al.
Object Type: Article
System: The UNT Digital Library
Literature review of environmental qualification of safety-related electric cables: Literature analysis and appendices. Volume 2 (open access)

Literature review of environmental qualification of safety-related electric cables: Literature analysis and appendices. Volume 2

In support of the US NRC Environmental Qualification (EQ) Research Program, a literature review was performed to identify past relevant work that could be used to help fully or partially resolve issues of interest related to the qualification of low-voltage electric cable. A summary of the literature reviewed is documented in Volume 1 of this report. In this, Volume 2 of the report, dossiers are presented which document the issues selected for investigation in this program, along with recommendations for future work to resolve the issues, when necessary. The dossiers are based on an analysis of the literature reviewed, as well as expert opinions. This analysis includes a critical review of the information available from past and ongoing work in thirteen specific areas related to EQ. The analysis for each area focuses on one or more questions which must be answered to consider a particular issue resolved. Results of the analysis are presented, along with recommendations for future work. The analysis is documented in the form of a dossier for each of the areas analyzed.
Date: April 1996
Creator: Lofaro, R.; Bowerman, B. & Carbonaro, J.
Object Type: Report
System: The UNT Digital Library
Multimedia Environmental Pollutant Assessment System (MEPAS{reg_sign}): Groundwater pathway formulations (open access)

Multimedia Environmental Pollutant Assessment System (MEPAS{reg_sign}): Groundwater pathway formulations

This report describes the mathematical formulations used for contaminant fate and transport in the groundwater pathway of the Multimedia Environmental Pollutant Assessment System (MEPAS). It is one in a series of reports that collectively describe the components of MEPAS. The groundwater component of the MEPAS methodology models solute transport through the groundwater environment (i.e., partially saturated and saturated zones). Specifically, this component provides estimates of groundwater contaminant fluxes at various transporting medium interfaces (e.g., water table or aquifer/river interface) and contaminant concentrations at withdrawal wells. Contaminant fluxes at transporting medium interfaces represent boundary conditions for the next medium in which contaminant migration and fate is to be simulated (e.g., groundwater contamination entering a surface-water environment). Contaminant concentrations at withdrawal wells provide contaminant levels for the exposure assessment component of MEPAS. A schematic diagram illustrating the groundwater environment is presented. The migration and fate of contaminants through the groundwater environment are described by the three-dimensional, advective-dispersive equation for solute transport. The results are based on semianalytical solutions (i.e., solutions that require numerical integration) that are well established in the scientific literature. To increase computational efficiency, limits of integration are also identified.
Date: June 1, 1996
Creator: Whelan, G.; McDonald, J.P. & Sato, C.
Object Type: Report
System: The UNT Digital Library
Approximate calculations of NO{sub x} formation in an oscillating flow field (open access)

Approximate calculations of NO{sub x} formation in an oscillating flow field

Chiefly for improved efficiency, the trend to increasing use of gas turbine engines in stationary powerplants has been firmly established. The requirement for minimum NOx production has motivated operation as close as practically possible near the lean flammability limit, to reduce formation of nitrogen oxides by the Zeldovich thermal mechanism. However, experience has shown that under these conditions, stability of the chamber is reduced, often leading to the presence of sustained oscillations in the combustor. That possibility raises the problem of the influence of oscillatory motions on the production of nitrogen oxides. The work represented in this paper covers the initial steps in constructing an analysis suitable for application to that problem in design and development of operational gas turbine combustors.
Date: June 1996
Creator: Swenson, G.; Pun, W. & Culick, F. E. C
Object Type: Article
System: The UNT Digital Library
Assessment of hydrologic transport of radionuclides from the Gnome underground nuclear test site, New Mexico (open access)

Assessment of hydrologic transport of radionuclides from the Gnome underground nuclear test site, New Mexico

The U.S. Department of Energy (DOE) is operating an environmental restoration program to characterize, remediate, and close non-Nevada Test Site locations that were used for nuclear testing. Evaluation of radionuclide transport by groundwater from these sites is an important part of the preliminary site risk analysis. These evaluations are undertaken to allow prioritization of the test areas in terms of risk, provide a quantitative basis for discussions with regulators and the public about future work at the sites, and provide a framework for assessing data needs to be filled by site characterization. The Gnome site in southeastern New Mexico was the location of an underground detonation of a 3.5-kiloton nuclear device in 1961, and a hydrologic tracer test using radionuclides in 1963. The tracer test involved the injection of tritium, {sup 90}Sr, and {sup 137}Cs directly into the Culebra Dolomite, a nine to ten-meter-thick aquifer located approximately 150 in below land surface. The Gnome nuclear test was carried out in the Salado Formation, a thick salt deposit located 200 in below the Culebra. Because salt behaves plastically, the cavity created by the explosion is expected to close, and although there is no evidence that migration has actually occurred, it is …
Date: September 1, 1996
Creator: Earman, S.; Chapman, J.; Pohlmann, K. & Andricevic, R.
Object Type: Report
System: The UNT Digital Library
Transient dynamics simulations: Parallel algorithms for contact detection and smoothed particle hydrodynamics (open access)

Transient dynamics simulations: Parallel algorithms for contact detection and smoothed particle hydrodynamics

Transient dynamics simulations are commonly used to model phenomena such as car crashes, underwater explosions, and the response of shipping containers to high-speed impacts. Physical objects in such a simulation are typically represented by Lagrangian meshes because the meshes can move and deform with the objects as they undergo stress. Fluids (gasoline, water) or fluid-like materials (earth) in the simulation can be modeled using the techniques of smoothed particle hydrodynamics. Implementing a hybrid mesh/particle model on a massively parallel computer poses several difficult challenges. One challenge is to simultaneously parallelize and load-balance both the mesh and particle portions of the computation. A second challenge is to efficiently detect the contacts that occur within the deforming mesh and between mesh elements and particles as the simulation proceeds. These contacts impart forces to the mesh elements and particles which must be computed at each timestep to accurately capture the physics of interest. In this paper we describe new parallel algorithms for smoothed particle hydrodynamics and contact detection which turn out to have several key features in common. Additionally, we describe how to join the new algorithms with traditional parallel finite element techniques to create an integrated particle/mesh transient dynamics simulation. Our approach …
Date: September 1, 1996
Creator: Hendrickson, B.; Plimpton, S.; Attaway, S. & Swegle, J.
Object Type: Article
System: The UNT Digital Library
German-Texan Heritage Society, The Journal, Volume 18, Number 2, Summer 1996 (open access)

German-Texan Heritage Society, The Journal, Volume 18, Number 2, Summer 1996

Quarterly publication of the German-Texan Heritage Society providing information about news and events related to the work of the organization as well as stories, articles, genealogical data and other information of interest to members collected from representatives across Texas.
Date: Summer 1996
Creator: German-Texan Heritage Society
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Nanoindentation of soft films on hard substrates: The importance of pile-up (open access)

Nanoindentation of soft films on hard substrates: The importance of pile-up

Nanoindentation is used for measuring mechanical properties of thin films. This paper addresses potential measurement errors caused by pile-up when soft films deposited on hard substrates are tested this way. Pile-up is exacerbated in soft film/hard substrate systems because of the constraint the substrate exerts on plastic deformation of the film. To examine pile-up effects, Al films 240 and 1700 nm thick were deposited on hard glass and tested by standard nanoindentation. In Al/glass, the film and substrate have similar elastic moduli; thus, any unusual behavior in nanoindentation results may be attributed to differences in plastic flow alone. SEM examination of nanoindentation hardness impressions in the film revealed that common methods for analyzing nanoindentation data underestimate the true contact areas by as much as 80%, which results in overestimations of the hardness and modulus by as much as 80 and 35%, respectively. Sources of these errors and their effect on measurement of hardness and elastic modulus are discussed, and a simple model for the composite hardness of the film/substrate system is developed. This model could prove useful when it is not possible to make indentations shallow enough to avoid substrate effects.
Date: May 1, 1996
Creator: Tsui, T. Y.; Pharr, G. M. & Oliver, W. C.
Object Type: Article
System: The UNT Digital Library
Aging management guideline for commercial nuclear power plants - tanks and pools (open access)

Aging management guideline for commercial nuclear power plants - tanks and pools

Continued operation of nuclear power plants for periods that extend beyond their original 40-year license period is a desirable option for many U.S. utilities. U.S. Nuclear Regulatory Commission (NRC) approval of operating license renewals is necessary before continued operation becomes a reality. Effective aging management for plant components is important to reliability and safety, regardless of current plant age or extended life expectations. However, the NRC requires that aging evaluations be performed and the effectiveness of aging management programs be demonstrated for components considered within the scope of license renewal before granting approval for operation beyond 40 years. Both the NRC and the utility want assurance that plant components will be highly reliable during both the current license term and throughout the extended operating period. In addition, effective aging management must be demonstrated to support Maintenance Rule (10 CFR 50.65) activities.
Date: February 1, 1996
Creator: Blocker, E.; Smith, S.; Philpot, L. & Conley, J.
Object Type: Report
System: The UNT Digital Library
Low-level liquid radioactive waste treatment at Murmansk, Russia: Technical design and review of facility upgrade and expansion (open access)

Low-level liquid radioactive waste treatment at Murmansk, Russia: Technical design and review of facility upgrade and expansion

The governments of Norway and the US have committed their mutual cooperation and support the Murmansk Shipping Company (MSCo) to expand and upgrade the Low-Level Liquid Radioactive Waste (LLRW) treatment system located at the facilities of the Russian company RTP Atomflot, in Murmansk, Russia. RTP Atomflot provides support services to the Russian icebreaker fleet operated by the MSCo. The objective is to enable Russia to permanently cease disposing of this waste in Arctic waters. The proposed modifications will increase the facility`s capacity from 1,200 m{sup 3} per year to 5,000 m{sup 3} per year, will permit the facility to process high-salt wastes from the Russian Navy`s Northern fleet, and will improve the stabilization and interim storage of the processed wastes. The three countries set up a cooperative review of the evolving design information, conducted by a joint US and Norwegian technical team from April through December, 1995. To ensure that US and Norwegian funds produce a final facility which will meet the objectives, this report documents the design as described by Atomflot and the Russian business organization, ASPECT, both in design documents and orally. During the detailed review process, many questions were generated, and many design details developed which are …
Date: July 1, 1996
Creator: Dyer, R. S.; Diamante, J. M. & Duffey, R. B.
Object Type: Report
System: The UNT Digital Library
The Witness, Yearbook of the Texas Academy of Mathematics and Science, 1996 (open access)

The Witness, Yearbook of the Texas Academy of Mathematics and Science, 1996

Yearbook for the Texas Academy of Mathematics and Science (TAMS) in Denton, Texas includes photographs of and information about the program, student body, classes, and organizations.
Date: 1996
Creator: Texas Academy of Mathematics and Science
Object Type: Yearbook
System: The UNT Digital Library
Advanced radiant combustion system. Final report, September 1989--September 1996 (open access)

Advanced radiant combustion system. Final report, September 1989--September 1996

Results of the Advanced Radiant Combustion System (ARCS) project are presented in this report. This work was performed by Alzeta Corporation as prime contractor under a contract to the U.S. Department of Energy Office of Industrial Technologies as part of a larger DOE program entitled Research Program for Advanced Combustion Systems. The goals of the Alzeta ARCS project were to (a) Improve the high temperature performance characteristics of porous surface ceramic fiber burners, (b) Develop an Advanced Radiant Combustion System (ARCS) that combines combustion controls with an advanced radiant burner, and (c) Demonstrate the advanced burner and controls in an industrial application. Prior to the start of this project, Alzeta had developed and commercialized a porous surface radiant burner, the Pyrocore{trademark} burner. The product had been commercially available for approximately 5 years and had achieved commercial success in a number of applications ranging from small burners for commercial cooking equipment to large burners for low temperature industrial fluid heating applications. The burner was not recommended for use in applications with process temperatures above 1000{degrees}F, which prevented the burner from being used in intermediate to high temperature processes in the chemical and petroleum refining industries. The interest in increasing the maximum …
Date: September 1, 1996
Creator: Sullivan, J.D.; Carswell, M.G. & Long, F.S.
Object Type: Report
System: The UNT Digital Library
Offsite environmental monitoring report: Radiation monitoring around United States nuclear test areas, calendar year 1993 (open access)

Offsite environmental monitoring report: Radiation monitoring around United States nuclear test areas, calendar year 1993

This report describes the Offsite Radiation Safety Program conducted during 1993 by the Environmental Protection Agency`s (EPA`s) Environmental Monitoring Systems Laboratory - Las Vegas (EMSL-LV). This laboratory operates an environmental radiation monitoring program in the region surrounding the Nevada Test Site (NTS) and at former test sites in Alaska, Colorado, Mississippi, Nevada, and New Mexico. The surveillance program is designed to measure levels and trends of radioactivity, if present, in the environment surrounding testing areas to ascertain whether current radiation levels and associated doses to the general public are in compliance with existing radiation protection standards. The surveillance program additionally has the responsibility to take action to protect the health and well being of the public in the event of any accidental release of radioactive contaminants. Offsite levels of radiation and radioactivity are assessed by sampling milk, water, and air; by deploying thermoluminescent dosimeters (TLDs) and using pressurized ionization chambers (PICs); by biological monitoring of foodstuffs including animal tissues and food crops; and by measurement of radioactive material deposited in humans.
Date: June 1, 1996
Creator: Chaloud, D. J; Daigler, D. M. & Davis, M.G.
Object Type: Report
System: The UNT Digital Library
The formation of metal/metal-matrix nano-composites by the ultrasonic dispersion of immiscible liquid metals (open access)

The formation of metal/metal-matrix nano-composites by the ultrasonic dispersion of immiscible liquid metals

Ultrasonic energy has been used to disperse one liquid metallic component in a second immiscible liquid metal, thereby producing a metallic emulsion. Upon lowering the temperature of this emulsion below the mp of the lowest-melting constituent, a metal/metal-matrix composite is formed. This composite consists of sub-micron-to-micron- sized particles of the minor metallic phase that are embedded in a matrix consisting of the major metallic phase. Zinc-bismuth was used as a model system, and ultrasonic dispersion of a minor Bi liquid phase was used to synthesize metal/metal-matrix composites. These materials were characterized using SEM and energy-dispersive x-ray analysis.
Date: December 1, 1996
Creator: Keppens, V. M.; Mandrus, D.; Boatner, L. A. & Rankin, J.
Object Type: Article
System: The UNT Digital Library
A field-scale demonstration of air sparging to remediate tritiated fluids (open access)

A field-scale demonstration of air sparging to remediate tritiated fluids

Two pilot field-scale studies were conducted during the period of May 24 to July 22, 1996, to evaluate the potential of air sparging to remediate tritiated fluids. Previous analytical solutions to the rate of tritium removal were evaluated and compared to the experimental results. The analytical solution of Craig and Gordon that describes isotopic fractionation of an evaporating body of water appears to most accurately describe the process, versus the more limited isotopic exchange equation of Slattery and Ingraham and the mass transfer equation of Wilson and Fordham, which are accurate only at moderate to high humidities and do not describe the tritium enrichment process that would occur at low humidities. The results of the two experiments demonstrated that air sparging of tritium is a viable process in the field. Tritium removal rates of 60 percent were reported during the first experiment and 66 percent for the second experiment. Comparison to previous laboratory work revealed that rates could have been improved by starting with higher concentrations, utilizing smaller bubbles, and longer bubble path lengths. Risks associated with the pilot study were greater the closer one worked to the experiment with a maximum increase in the Lifetime Excess Total Risk per …
Date: September 1, 1996
Creator: Russell, C. E.; Gillespie, D. R.; Hokett, S. L. & Donithan, J. D.
Object Type: Report
System: The UNT Digital Library
Winnetka deformation zone: Surface expression of coactive slip on a blind fault during the Northridge earthquake sequence, California. Evidence that coactive faulting occurred in the Canoga Park, Winnetka, and Northridge areas during the 17 January 1994, Northridge, California earthquake (open access)

Winnetka deformation zone: Surface expression of coactive slip on a blind fault during the Northridge earthquake sequence, California. Evidence that coactive faulting occurred in the Canoga Park, Winnetka, and Northridge areas during the 17 January 1994, Northridge, California earthquake

Measurements of normalized length changes of streets over an area of 9 km{sup 2} in San Fernando Valley of Los Angeles, California, define a distinctive strain pattern that may well reflect blind faulting during the 1994 Northridge earthquake. Strain magnitudes are about 3 {times} 10{sup {minus}4}, locally 10{sup {minus}3}. They define a deformation zone trending diagonally from near Canoga Park in the southwest, through Winnetka, to near Northridge in the northeast. The deformation zone is about 4.5 km long and 1 km wide. The northwestern two-thirds of the zone is a belt of extension of streets, and the southeastern one-third is a belt of shortening of streets. On the northwest and southeast sides of the deformation zone the magnitude of the strains is too small to measure, less than 10{sup {minus}4}. Complete states of strain measured in the northeastern half of the deformation zone show that the directions of principal strains are parallel and normal to the walls of the zone, so the zone is not a strike-slip zone. The magnitudes of strains measured in the northeastern part of the Winnetka area were large enough to fracture concrete and soils, and the area of larger strains correlates with the area …
Date: December 31, 1996
Creator: Cruikshank, K. M.; Johnson, A. M.; Fleming, R. W. & Jones, R. L.
Object Type: Report
System: The UNT Digital Library
Carbon dioxide, hydrographic, and chemical data obtained during the R/V Meteor Cruise 18/1 in the North Atlantic Ocean (WOCE Section A1E, September 1991) (open access)

Carbon dioxide, hydrographic, and chemical data obtained during the R/V Meteor Cruise 18/1 in the North Atlantic Ocean (WOCE Section A1E, September 1991)

The North Atlantic Ocean is characterized by an intense meridional circulation cell carrying near-surface waters of tropical and subtropical origin northward and deep waters of arctic and subarctic origin southward. The related {open_quotes}overturning{close_quotes} is driven by the sinking of water masses at high latitudes. The overturning rate and thus the intensity of the meridional transports of mass, heat, and salt, is an important control parameter for the modeling of the ocean`s role in climate. The Research Vessel (R/V) Meteor Cruise 18/1 was one in a series of cruises in the North Atlantic that started in March 1991 and continued until 1995. This data documentation discusses the procedures and methods used to measure total carbon dioxide (TCO{sub 2}) and total alkalinity (TALK) at hydrographic stations, as well as underway partial pressure of CO{sub 2} (pCO{sub 2}) measured during the RIV Meteor Cruise 18/1 in the North Atlantic Ocean (Section A1E). Conducted as part of the World Ocean Circulation Experiment (WOCE) and the German North Atlantic Overturning Rate Determination expedition, the cruise began in Reykjavik, Iceland, on September 2, 1991, and ended after 24 days at sea in Hamburg, Germany, on September 25, 1991. WOCE Zonal Section AlE began at 60{degrees}N and …
Date: July 1, 1996
Creator: Johnson, K.M.; Wallace, D.W.R.; Schneider, B.; Mintrop, L. & Kozyr, A.
Object Type: Report
System: The UNT Digital Library
Chronicles of Oklahoma, Volume 74, Number 2, Summer 1996 (open access)

Chronicles of Oklahoma, Volume 74, Number 2, Summer 1996

Quarterly publication containing articles, book reviews, photographs, illustrations, and other works documenting Oklahoma history and preservation.
Date: Summer 1996
Creator: Oklahoma Historical Society
Object Type: Journal/Magazine/Newsletter
System: The Gateway to Oklahoma History
Agriculture, land use, and commercial biomass energy (open access)

Agriculture, land use, and commercial biomass energy

In this paper we have considered commercial biomass energy in the context of overall agriculture and land-use change. We have described a model of energy, agriculture, and land-use and employed that model to examine the implications of commercial biomass energy or both energy sector and land-use change carbon emissions. In general we find that the introduction of biomass energy has a negative effect on the extent of unmanaged ecosystems. Commercial biomass introduces a major new land use which raises land rental rates, and provides an incentive to bring more land into production, increasing the rate of incursion into unmanaged ecosystems. But while the emergence of a commercial biomass industry may increase land-use change emissions, the overall effect is strongly to reduce total anthropogenic carbon emissions. Further, the higher the rate of commercial biomass energy productivity, the lower net emissions. Higher commercial biomass energy productivity, while leading to higher land-use change emissions, has a far stronger effect on fossil fuel carbon emissions. Highly productive and inexpensive commercial biomass energy technologies appear to have a substantial depressing effect on total anthropogenic carbon emissions, though their introduction raises the rental rate on land, providing incentives for greater rates of deforestation than in the …
Date: June 1, 1996
Creator: Edmonds, J. A.; Wise, M. A.; Sands, R. D.; Brown, R. A. & Kheshgi, H.
Object Type: Report
System: The UNT Digital Library
Midnite Mine Summary Report (open access)

Midnite Mine Summary Report

The Midni'e Mine is an inactive, hard-rock uranium mine in Stevens County, WA. Oxidation of sulfide-containing minerals in the ore body produces large quantities of acidic water. The U.S. Bureau of Mines was directed by Congress in Fiscal Year 1994 to perform technological research on the treatment of radioactive water and disposal of treatment residues at the Midnite Mine and en overall site reclamation. This Report of Investigations summarizes the studies that were completed on: 1) treatment alternatives for uranium contaminated acid mine drainage, and 2) overall site reclamation, including: ground water flowpaths in the bedrock, radiation, and waste rock reactivity. As an aid to site reclamation, a Geographic Information System database was also produced that contains available current and historic data and information on the Midnite Mine. This report explains the scope of the Bureau's study and summarizes the results of its investigations.
Date: 1996
Creator: Dean, N. E.; Boldt, C. M. K.; Schultze, L. E.; Nilsen, D. N.; Isaacson, A. E.; Williams, B. C. et al.
Object Type: Report
System: The UNT Digital Library
Hanford Site National Environmental Policy Act (NEPA) characterization. Revision 8 (open access)

Hanford Site National Environmental Policy Act (NEPA) characterization. Revision 8

This eighth revision of the Hanford Site National Environmental Policy Act (NEPA) Characterization presents current environmental data regarding the Hanford Site and its immediate environs. This information is intended for use in preparing Chapters 4 and 6 in Hanford Site-related NEPA documents. Chapter 4 (Affected Environment) includes information on climate and meteorology, geology, hydrology, ecology, historical, archaeological and cultural resources, socioeconomics, and noise. Chapter 6 (Statutory and Regulatory Requirements) provides the preparer with the federal and state regulations, DOE directives and permits, and environmental standards directly applicable to the NEPA documents on the Hanford Site. The following sections were updated in this revision: climate and meteorology; ecology (threatened and endangered species section only); historical; archaeological and cultural resources; and all of chapter 6. No conclusions or recommendations are given in this report. Rather, it is a compilation of information on the Hanford Site environment that can be used directly by Site contractors. This information can also be used by any interested individual seeking baseline data on the hanford Site and its past activities by which to evaluate projected activities and their impacts.
Date: August 1, 1996
Creator: Neitzel, D. A.; Bjornstad, B. N.; Fosmire, C. J. & Fowler, R. A.
Object Type: Report
System: The UNT Digital Library
Development of mercury and chloride monitors for coal gasifiers (open access)

Development of mercury and chloride monitors for coal gasifiers

Ames Laboratory will develop an integrated sampling and analysis system suitable for on-line monitoring of mercury (Hg) and hydrogen chloride (HCl) in advanced coal-based gasifiers. The objectives of this project are to (1) summarize current technology for monitoring Hg and HCl in gaseous effluents; (2) identify analytical techniques for such determinations in high-temperature, high-pressure gases from coal-based systems for producing electrical power; (3) evaluate promising analytical approaches, and (4) produce reliable on-line monitors which are adaptable to plant-scale diagnostics and process control. For HG, the techniques selected for further consideration were atomic absorption and atomic fluorescence. For HCl, non-dispersive infrared absorption, a dry colorimetric procedure, and ion mobility spectroscopy were selected for testing in the laboratory. Results to date are described.
Date: December 31, 1996
Creator: Buttermore, W. H.; Norton, G. A.; Chriswell, C. D.; Eckels, D. E. & Peters, R. E.
Object Type: Article
System: The UNT Digital Library
Performance measures for evaluating public participation activities in DOE`s Office of Environmental Management (open access)

Performance measures for evaluating public participation activities in DOE`s Office of Environmental Management

Public participation in decision-making in the United States has become a dominant theme throughout the public sector and is increasingly used in the private sector. Recent reports by the National Research Council and the Commission on Risk Assessment and Risk Management, set up jointly by the White House and Congress, conclude that risk decisions must increasingly be structured in such a manner as to involve stakeholders meaningfully in the processes and activities leading to decisions and, perhaps, through decision implementation. Both of these reports indicate that decisions may take longer but be better if officials: (1) bring all interested and affected parties to the table at the beginning of the risk-discussion process; (2) identify relevant concerns, losses, exposures and other information the parties have; (3) address significant concerns through appropriate research; and (4) present findings in an understandable, accessible way. This report is intended to facilitate subsequent evaluations of public participation activities and programs.
Date: August 1, 1996
Creator: Carnes, S. A.; Schweitzer, M.; Peelle, E. B.; Wolfe, A. K. & Munro, J. F.
Object Type: Report
System: The UNT Digital Library
MP Salsa: a finite element computer program for reacting flow problems. Part 1--theoretical development (open access)

MP Salsa: a finite element computer program for reacting flow problems. Part 1--theoretical development

The theoretical background for the finite element computer program, MPSalsa, is presented in detail. MPSalsa is designed to solve laminar, low Mach number, two- or three-dimensional incompressible and variable density reacting fluid flows on massively parallel computers, using a Petrov-Galerkin finite element formulation. The code has the capability to solve coupled fluid flow, heat transport, multicomponent species transport, and finite-rate chemical reactions, and to solver coupled multiple Poisson or advection-diffusion- reaction equations. The program employs the CHEMKIN library to provide a rigorous treatment of multicomponent ideal gas kinetics and transport. Chemical reactions occurring in the gas phase and on surfaces are treated by calls to CHEMKIN and SURFACE CHEMKIN, respectively. The code employs unstructured meshes, using the EXODUS II finite element data base suite of programs for its input and output files. MPSalsa solves both transient and steady flows by using fully implicit time integration, an inexact Newton method and iterative solvers based on preconditioned Krylov methods as implemented in the Aztec solver library.
Date: May 1, 1996
Creator: Shadid, J. N.; Moffat, H. K.; Hutchinson, S. A.; Hennigan, G. L.; Devine, K. D. & Salinger, A. G.
Object Type: Report
System: The UNT Digital Library