Algorithm for Rapid Tomography of Gas Concentrations (open access)

Algorithm for Rapid Tomography of Gas Concentrations

We present a new computed tomography method, the low third derivative (LTD) method, that is particularly suited for reconstructing the spatial distribution of gas concentrations from path-integral data for a small number of optical paths. The method finds a spatial distribution of gas concentrations that (1) has path integrals that agree with measured path integrals, and (2) has a low third spatial derivative in each direction, at every point. The trade-off between (1) and (2) is controlled by an adjustable parameter, which can be set based on analysis of the path-integral data. The method produces a set of linear equations, which can be solved with a single matrix multiplication if the constraint that all concentrations must be positive is ignored; the method is therefore extremely rapid. Analysis of experimental data from thousands of concentration distributions shows that the method works nearly as well as Smooth Basis Function Minimization (the best method previously available), yet is 100 times faster.
Date: June 27, 2000
Creator: Price, P. N.; Fischer, M. L.; Gadgil, A. J. & Sextro, R. G.
Object Type: Article
System: The UNT Digital Library
Using pseudo transient continuation and the finite element method to solve the nonlinear Poisson-Boltzmann equation (open access)

Using pseudo transient continuation and the finite element method to solve the nonlinear Poisson-Boltzmann equation

The nonlinear Poisson-Boltzmann (PB) equation is solved using Pseudo Transient Continuation. The PB solver is constructed by modifying the nonlinear diffusion module of a 3D, massively parallel, unstructured-grid, finite element, radiation-hydrodynamics code. The solver also computes the electrostatic energy and evaluates the force on a user-specified contour. Either Dirichlet or mixed boundary conditions are allowed. The latter specifies surface charges, approximates far-field conditions, or linearizes conditions ''regulating'' the surface charge. The code may be run in either Cartesian, cylindrical, or spherical coordinates. The potential and force due to a conical probe interacting with a flat plate is computed and the result compared with direct force measurements by chemical force microscopy.
Date: December 27, 2000
Creator: Shestakov, A I; Milovich, J L & Noy, A
Object Type: Article
System: The UNT Digital Library
Pulse height spectrum measurement experiment for code benchmarking: first results (open access)

Pulse height spectrum measurement experiment for code benchmarking: first results

The authors have completed a set of gamma-ray pulse height benchmark experiments using a high purity germanium detector to measure absolute counting rate spectra from {sup 60}Co, {sup 137}Cs and {sup 57}Co isotopic sources. The detector was carefully shielded and collimated so that the geometry of the system was completely known. The measured absolute pulse height spectrum counting rates as a function of detector position relative to the source are compared to energy deposit spectra calculated using the Monte Carlo radiation transport code COG. They present here a small subset of our results. The agreement between the calculated and measured spectra and known sources of discrepancies will be discussed.
Date: October 27, 2000
Creator: Sale, K E; Hall, J M & Brown, C M
Object Type: Article
System: The UNT Digital Library
Plutonium Immobilization Project Ceramic Prototype Test Facility Conceptual Design Layout (FY00 Milestone 6.2.5) (open access)

Plutonium Immobilization Project Ceramic Prototype Test Facility Conceptual Design Layout (FY00 Milestone 6.2.5)

None
Date: September 27, 2000
Creator: Marra, J. C. & Armantrout, G.
Object Type: Report
System: The UNT Digital Library
Guidelines - A Primer for Communicating Effectively with NABIR Stakeholders (open access)

Guidelines - A Primer for Communicating Effectively with NABIR Stakeholders

This primer is a tool to help prepare scientists for meetings with stakeholders. It was prepared for staff involved with the Natural and Accelerated Bioremediation Research (NABIR) program, sponsored by the U.S. Department of Energy. It discusses why some efforts in science communication may succeed while others fail, provides methods of approaching group interactions about science that may better orient expert participants, and summarizes experience drawn from observations of groups interacting about topics in bioremediation or the NABIR program. The primer also provides brief, useful models for interacting with either expert or non-expert groups. Finally, it identifies topical areas that may help scientists prepare for public meetings, based on the developers' ongoing research in science communication in public forums.
Date: September 27, 2000
Creator: Bilyard, Gordon R.; Word, Charlotte J.; Weber, James R. & Harding, Anna K.
Object Type: Report
System: The UNT Digital Library
Alternative TRUEX-Based Pretreatment Processing of INEEL Sodium Bearing Waste (open access)

Alternative TRUEX-Based Pretreatment Processing of INEEL Sodium Bearing Waste

The goals of this study were to demonstrate a selective complexant for separating mercury from the transuranic (TRU) elements in the transuranic extraction (TRUEX) process and to demonstrate alternative stripping methods to eliminate phosphorus-containing, actinide stripping agents during TRUEX processing. The work described in this report provides the basis for implementing an improved TRUEX-based flowsheet for processing INEEL sodium-bearing waste using only minor modifications to the current Idaho National Engineering and Environmental Laboratory (INEEL) flowsheet design.
Date: September 27, 2000
Creator: Rapko, Brian M.; Fiskum, Sandra K. & Lumetta, Gregg J.
Object Type: Report
System: The UNT Digital Library
Hanford Site Environmental Surveillance Master Sampling Schedule (open access)

Hanford Site Environmental Surveillance Master Sampling Schedule

This document contains the CY2000 schedules for the routine collection of samples for the Surface Environmental Surveillance Project (SESP) and Drinking Water Monitoring Project. Each section includes sampling locations, sample types, and analyses to be performed.
Date: January 27, 2000
Creator: Bisping, Lynn E.
Object Type: Report
System: The UNT Digital Library
User's Guide for MetView: A Meteorological Display and Assessment Tool (open access)

User's Guide for MetView: A Meteorological Display and Assessment Tool

MetView Version 2.0 is an easy-to-use model for accessing, viewing, and analyzing meteorological data. MetView provides both graphical and numerical displays of data. It can accommodate data from an extensive meteorological monitoring network that includes near-surface monitoring locations, instrumented towers, sodars, and meteorologist observations. MetView is used operationally for both routine, emergency response, and research applications at the U.S. Department of Energy's Hanford Site. At the Site's Emergency Operations Center, MetView aids in the access, visualization, and interpretation of real-time meteorological data. Historical data can also be accessed and displayed. Emergency response personnel at the Emergency Operations Center use MetView products in the formulation of protective action recommendations and other decisions. In the initial stage of an emergency, MetView can be operated using a very simple, five-step procedure. This first-responder procedure allows non-technical staff to rapidly generate meteorological products and disseminate key information. After first-responder information products are produced, the Emergency Operations Center's technical staff can conduct more sophisticated analyses using the model. This may include examining the vertical variation in winds, assessing recent changes in atmospheric conditions, evaluating atmospheric mixing rates, and forecasting changes in meteorological conditions. This user's guide provides easy-to-follow instructions for both first-responder and routine operation …
Date: September 27, 2000
Creator: Glantz, Clifford S.; Pelton, Mitchell A.; Allwine, K Jerry & Burk, Kenneth W.
Object Type: Report
System: The UNT Digital Library
Cooperative Research in C1 Chemistry (open access)

Cooperative Research in C1 Chemistry

None
Date: April 27, 2000
Creator: Huffman, Gerald P.
Object Type: Report
System: The UNT Digital Library
Cooperative Research in C1 Chemistry (open access)

Cooperative Research in C1 Chemistry

C1 chemistry refers to the conversion of simple carbon-containing materials that contain one carbon atom per molecule into valuable products. The feedstocks for C1 chemistry include natural gas, carbon dioxide, carbon monoxide, methanol and synthesis gas (a mixture of carbon monoxide and hydrogen). Synthesis gas, or syngas, is produced primarily by the reaction of natural gas, which is principally methane, with steam. It can also be produced by gasification of coal, petroleum coke, or biomass. The availability of syngas from coal gasification is expected to increase significantly in the future because of increasing development of integrated gasification combined cycle (IGCC) power generation. Because of the abundance of remote natural gas, the advent of IGCC, and environmental advantages, C1 chemistry is expected to become a major area of interest for the transportation fuel and chemical industries in the relatively near future. The CFFLS will therefore perform a valuable national service by providing science and engineering graduates that are trained in this important area. Syngas is the source of most hydrogen. Approximately 10 trillion standard cubic feet (SCF) of hydrogen are manufactured annually in the world. Most of this hydrogen is currently used for the production of ammonia and in a variety …
Date: October 27, 2000
Creator: Huffman, Gerald P.
Object Type: Report
System: The UNT Digital Library
Performance Confirmation Data Aquisition System (open access)

Performance Confirmation Data Aquisition System

The purpose of this analysis is to identify and analyze concepts for the acquisition of data in support of the Performance Confirmation (PC) program at the potential subsurface nuclear waste repository at Yucca Mountain. The scope and primary objectives of this analysis are to: (1) Review the criteria for design as presented in the Performance Confirmation Data Acquisition/Monitoring System Description Document, by way of the Input Transmittal, Performance Confirmation Input Criteria (CRWMS M&O 1999c). (2) Identify and describe existing and potential new trends in data acquisition system software and hardware that would support the PC plan. The data acquisition software and hardware will support the field instruments and equipment that will be installed for the observation and perimeter drift borehole monitoring, and in-situ monitoring within the emplacement drifts. The exhaust air monitoring requirements will be supported by a data communication network interface with the ventilation monitoring system database. (3) Identify the concepts and features that a data acquisition system should have in order to support the PC process and its activities. (4) Based on PC monitoring needs and available technologies, further develop concepts of a potential data acquisition system network in support of the PC program and the Site Recommendation …
Date: October 27, 2000
Creator: Markman, D. W.
Object Type: Report
System: The UNT Digital Library
Ultradense Quark Stars From Perturbative QCD. (open access)

Ultradense Quark Stars From Perturbative QCD.

None
Date: August 27, 2000
Creator: Fraga, E. S.
Object Type: Article
System: The UNT Digital Library
Small Neutrino Masses from Supersymmetry Breaking (open access)

Small Neutrino Masses from Supersymmetry Breaking

An alternative to the conventional see-saw mechanism is proposed to explain the origin of small neutrino masses in supersymmetric theories. The masses and couplings of the right-handed neutrino field are suppressed by supersymmetry breaking, in a way similar to the suppression of the Higgs doublet mass, $\mu$. New mechanisms for light Majorana, Dirac and sterile neutrinos arise, depending on the degree of suppression. Superpartner phenomenology is greatly altered by the presence of weak scale right-handed sneutrinos, which may have a coupling to a Higgs boson and a left-handed sneutrino. The sneutrino spectrum and couplings are quite unlike the conventional case - the lightest sneutrino can be the dark matter and predictions are given for event rates at upcoming halo dark matter direct detection experiments. Higgs decays and search strategies are changed. Copious Higgs production at hadron colliders can result from cascade decays of squarks and gluinos.
Date: June 27, 2000
Creator: Arkani-Hamed, Nima; Hall, Lawrence; Murayama, Hitoshi; Smith, David & Weiner, Neal
Object Type: Article
System: The UNT Digital Library
Selection rules in three-body B decay from factorization (open access)

Selection rules in three-body B decay from factorization

None
Date: July 27, 2000
Creator: Suzuki, M.
Object Type: Article
System: The UNT Digital Library
Isotope Geochemistry of Calcite Coatings and the Thermal History of the Unsaturated Zone at Yucca Mountain, Nevada (open access)

Isotope Geochemistry of Calcite Coatings and the Thermal History of the Unsaturated Zone at Yucca Mountain, Nevada

Calcite and opal coatings found on fracture footwalls and lithophysal cavity bottoms in the volcanic section at Yucca Mountain (exposed in a tunnel) contain a record of gradual chemical and isotopic changes that have occurred in the unsaturated zone. The thin (less than 6 cm) coatings are composed primarily of calcite, opal, chalcedony, and quartz. Fluid inclusions in calcite that homogenize at greater than ambient temperatures provide impetus for geochronologic studies in order to determine the thermal history. In the welded Topopah Spring Tuff (12.7 Ma), U-Pb ages of opal and chalcedony layers provide evidence of a long history of deposition throughout the past 10 m.y. However, these ages can constrain the ages of associated calcite layers only in samples with an easily interpretable microstratigraphy. Strontium isotope ratios in calcite increase with microstratigraphic position from the base up to the outermost surface of the coatings. The strontium incorporated in these coatings records the systematic change in pore-water isotopic composition due to water-rock interaction primarily in the overlying nonwelded tuffs. A one-dimensional advection-reaction model simulates strontium isotope ratios measured in pore water extracted from core in three vertical boreholes adjacent to the tunnel. By calculating the strontium isotope compositions of the …
Date: July 27, 2000
Creator: Marshall, B. D. & Whelan, J. F.
Object Type: Report
System: The UNT Digital Library
Comparing zonal and CFD models of air flows in large indoor spaces to experimental data (open access)

Comparing zonal and CFD models of air flows in large indoor spaces to experimental data

None
Date: October 27, 2000
Creator: Mora, Laurent; Gadgil, Ashok & Wurtz, Etienne
Object Type: Article
System: The UNT Digital Library
Integrated Site Model Process Report (open access)

Integrated Site Model Process Report

None
Date: January 27, 2000
Creator: Booth, T.
Object Type: Report
System: The UNT Digital Library
Disposal of Shippingport LWBR spent Nuclear Fuel in Yucca Mountain: Waste Package Internal Criticality Analysis (open access)

Disposal of Shippingport LWBR spent Nuclear Fuel in Yucca Mountain: Waste Package Internal Criticality Analysis

The paper presents the disposal criticality analysis for the Shippingport Light Water Breeder Reactor (LWBR) spent nuclear fuel (SNF) being considered for disposal at the potential Yucca Mountain repository. The methodology for disposal criticality analysis includes the evaluation of the potential configurations--intact through degraded--based on the supporting analyses of the physical and geochemical processes that degrade the fuel over time.
Date: September 27, 2000
Creator: Radulescu, H. R. & Davis, J. W.
Object Type: Report
System: The UNT Digital Library
The Rhode Island Nuclear Science Center conversion from HEU to LEU fuel (open access)

The Rhode Island Nuclear Science Center conversion from HEU to LEU fuel

The 2-MW Rhode Island Nuclear Science Center (RINSC) open pool reactor was converted from 93% UAL-High Enriched Uranium (HEU) fuel to 20% enrichment U3Si2-AL Low Enriched Uranium (LEU) fuel. The conversion included redesign of the core to a more compact size and the addition of beryllium reflectors and a beryllium flux trap. A significant increase in thermal flux level was achieved due to greater neutron leakage in the new compact core configuration. Following the conversion, a second cooling loop and an emergency core cooling system were installed to permit operation at 5 MW. After re-licensing at 2 MW, a power upgrade request will be submitted to the NRC.
Date: September 27, 2000
Creator: Tehan, Terry
Object Type: Report
System: The UNT Digital Library
Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf San Andres Reservoir. Quarterly Progress Report: July 1--September 30, 1999 (open access)

Application of Reservoir Characterization and Advanced Technology to Improve Recovery and Economics in a Lower Quality Shallow Shelf San Andres Reservoir. Quarterly Progress Report: July 1--September 30, 1999

The Class 2 Project at West Welch was designed to demonstrate the use of advanced technologies to enhance the economics of improved oil recovery (IOR) projects in lower quality Shallow Shelf Carbonate (SSC) reservoirs, resulting in recovery of additional oil that would otherwise be left in the reservoir at project abandonment. Accurate reservoir description is critical to the effective evaluation and efficient design of IOR projects in the heterogeneous SSC reservoirs. Therefore, the majority of Budget Period 1 was devoted to reservoir characterization. Technologies being demonstrated include: (1) Advanced petrophysics; (2) Three-dimensional (3-D) seismic; (3) Crosswell bore tomography; (4) Advanced reservoir simulation; (5) Carbon dioxide (CO{sub 2}) stimulation treatments; (6) Hydraulic fracturing design and monitoring; and (7) Mobility control agents.
Date: April 27, 2000
Creator: Kumar, Raj; Brown, Keith; Hickman, T. Scott & Justice, James J.
Object Type: Report
System: The UNT Digital Library
Fuel Retrieval System (FRS) Design Verification (open access)

Fuel Retrieval System (FRS) Design Verification

This document was prepared as part of an independent review to explain design verification activities already completed, and to define the remaining design verification actions for the Fuel Retrieval System. The Fuel Retrieval Subproject was established as part of the Spent Nuclear Fuel Project (SNF Project) to retrieve and repackage the SNF located in the K Basins. The Fuel Retrieval System (FRS) construction work is complete in the KW Basin, and start-up testing is underway Design modifications and construction planning are also underway for the KE Basin. An independent review of the design verification process as applied to the K Basin projects was initiated in support of preparation for the SNF Project operational readiness review (ORR).
Date: January 27, 2000
Creator: Yanocko, R. M.
Object Type: Report
System: The UNT Digital Library
Entanglement and Quantum Computation: An Overview (open access)

Entanglement and Quantum Computation: An Overview

This report presents a selective compilation of basic facts from the fields of particle entanglement and quantum information processing prepared for those non-experts in these fields that may have interest in an area of physics showing counterintuitive, ''spooky'' (Einstein's words) behavior. In fact, quantum information processing could, in the near future, provide a new technology to sustain the benefits to the U.S. economy due to advanced computer technology.
Date: June 27, 2000
Creator: Perez, R.B.
Object Type: Report
System: The UNT Digital Library
Tank Bump Accident Potential and Consequences During Waste Retrieval (open access)

Tank Bump Accident Potential and Consequences During Waste Retrieval

This report provides an evaluation of Hanford tank bump accident potential and consequences during waste retrieval operations. The purpose of this report is to consider the best available new information to support recommendations for safety controls. A new tank bump accident analysis for safe storage (Epstein et al. 2000) is extended for this purpose. A tank bump is a postulated event in which gases, consisting mostly of water vapor, are suddenly emitted from the waste and cause tank headspace pressurization. Tank bump scenarios, physical models, and frequency and consequence methods are fully described in Epstein et al. (2000). The analysis scope is waste retrieval from double-shell tanks (DSTs) including operation of equipment such as mixer pumps and air lift circulators. The analysis considers physical mechanisms for tank bump to formulate criteria for bump potential during retrieval, application of the criteria to the DSTs, evaluation of bump frequency, and consequence analysis of a bump. The result of the consequence analysis is the mass of waste released from tanks; radiological dose is calculated using standard methods (Cowley et al. 2000).
Date: September 27, 2000
Creator: BRATZEL, D.R.
Object Type: Report
System: The UNT Digital Library
Waste Transfer Leaks Control Decision Record (open access)

Waste Transfer Leaks Control Decision Record

Control decision meetings for Waste Transfer Leaks were held on April 24,25,26, and 27, 2000. The agenda for the control decision meetings is included in Appendix A, and attendee lists are included in Appendix B. The purpose of the control decision meetings was to review and revise previously selected controls for the prevention or mitigation of waste transfer leak accidents. Re-evaluation of the controls is warranted due to revisions in the hazard and accident analysis for these Tank Farm events. In particular, calculated radiological consequences are significantly reduced from those currently reported in the Final Safety Analysis Report (FSAR). Revised hazard and accident analysis and a revised control recommendation will be reflected in an Authorization Basis Amendment to be submitted at the Department of Energy, Office of River Protection's (ORP's) request by June 30, 2000 to satisfy ORP Performance Incentive (PI) 2.1.1, Revision 1, ''Authorization Basis Management Process Efficiency Improvement''. The scope of the control decision meetings was to address all waste transfer leak-related hazardous conditions identified in the Tank Farm hazard analysis database, excluding those associated with the use of the Replacement Cross-Site Transfer System (RCSTS) slurry line and sluicing of Tank 241-C-106, which is addressed in FSAR Addendum …
Date: June 27, 2000
Creator: RYAN, G.W.
Object Type: Report
System: The UNT Digital Library