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The Concentration of (236)Pu Daughters in Plutonium for Application to MOX Production from Plutonium from Dismantled US Nuclear Weapons (open access)

The Concentration of (236)Pu Daughters in Plutonium for Application to MOX Production from Plutonium from Dismantled US Nuclear Weapons

The isotope {sup 236}Pu in the weapons-grade plutonium to be used in the US MOX (mixed-oxide) plant is of concern because the daughter products of {sup 236}Pu are sources of high-energy gamma rays. The {sup 208}Tl daughter of {sup 236}Pu emits intense, high-energy gamma rays that are important for radiation exposure calculations for plant design. It is generally thought that the concentrations of {sup 236}Pu and its daughters are well below 10{sup {minus}10}, but these concentrations are generally below the detection limits of most analytical techniques. One technique that can be used to determine the concentration {sup 208}Tl is the direct measurement of the intensity of the {sup 208}Tl gamma rays in the gamma-ray spectrum from plutonium. Thallium-208 will be in equilibrium with {sup 228}Th, and may very well be in equilibrium with {sup 232}U for most aged plutonium samples. We have used the FRAM isotopic analysis software to analyze dozens of archived high-resolution gamma ray spectra from various samples of US and foreign plutonium. We are able to quantify the ratio of minor isotopes with measurable gamma-ray emissions to the major isotope of plutonium and hence, through the measurement of the plutonium isotopic distribution of the sample, to elemental …
Date: May 1, 2001
Creator: Sampson, Thomas E. & Cremers, Teresa L.
Object Type: Report
System: The UNT Digital Library
Radiological Emissions and Environmental Monitoring for Brookhaven National Laboratory, 1947 - 1961. (open access)

Radiological Emissions and Environmental Monitoring for Brookhaven National Laboratory, 1947 - 1961.

Brookhaven National Laboratory (BNL) has monitored its releases to the environment since its inception in 1947. From 1962 to 1966 and from 1971 to the present, annual reports,were published that recorded the emissions and releases to the environment from Laboratory operations. In 1998, a report was written to summarize the environmental data for the years 1967 to 1970. One of the purposes of the current report is to complete BNL's environmental history by covering the period from 1948 through 1961. The activities in 1947 were primarily organizational and there is no information on the use of radiation at the Laboratory before 1948. An additional objective of this report is to provide environmental data to the Agency for Toxic Substances and Disease Registry (ATSDR). The report does not provide an estimate of the doses associated with BNL operations. The report is comprised of two parts. The first part is a summary of emissions, releases, and environmental monitoring information including a discussion of the uncertainties in these data. Part two contains the detailed information on the approach taken to estimate the releases from the fuel cartridge failures at the Brookhaven Graphite Research Reactor (BGRR). A series of appendices present more detailed information …
Date: May 30, 2001
Creator: Meinhold, C. B.; Meinhold, A. F. &
Object Type: Report
System: The UNT Digital Library
EFFECTS OF MINERALOGY, GRAIN SIZE, AND SOLUTION COMPOSITION ON LITHIUM SORPTION TO SATURATED ALLUVIUM SOUTH OF YUCCA MOUNTAIN, NEVADA (open access)

EFFECTS OF MINERALOGY, GRAIN SIZE, AND SOLUTION COMPOSITION ON LITHIUM SORPTION TO SATURATED ALLUVIUM SOUTH OF YUCCA MOUNTAIN, NEVADA

Lithium is used frequently as a surrogate for cationic radionuclides such as NpO{sub 2}{sup +} in field and laboratory settings. Current plans include the use of Li{sup +} as a reactive tracer in field tracer testing in the saturated alluvium south of Yucca Mountain, NV, site of a potential high-level nuclear waste. Characterization of the alluvial material for grain size, mineralogy, cation exchange capacity (CEC), and surface area yields data that is compared with lithium batch sorption as a first step in inferring radionuclide transport behavior. This research will be used to help assess performance of the potential repository.
Date: May 1, 2001
Creator: Sullivan, E. J.; Reimus, P. W. & Ding, M.
Object Type: Article
System: The UNT Digital Library
A Tritiated-Water Detector with U-232/Th-228 Source (open access)

A Tritiated-Water Detector with U-232/Th-228 Source

The detection capabilities of the new U-232/Th-228 source are comparable to those of the Na-24 source. The main benefit in using the new source is the ease of operation. Elimination of the neutron activation step required for Na-24 sources saves about 24 hours in planning, scheduling, and executing. With the new U-232/Th-228 source, the monitor can be put in operation in less than 15 minutes. The long half-life of the U-232/Th-228 source also eliminates the need to record calibration and measurement times, as required for decay corrections when using a Na-24 source.
Date: May 29, 2001
Creator: Baumann, N.P.
Object Type: Article
System: The UNT Digital Library
FULLY KINETIC SIMULATIONS OF SLOW-MODE SHOCKS (open access)

FULLY KINETIC SIMULATIONS OF SLOW-MODE SHOCKS

Much of the theoretical understanding concerning the structure and essential properties of the slow-mode shock has been obtained from extensive hybrid calculations in which a full kinetic description is retained for the ions while the electrons are approximated as a massless adiabatic fluid. Due to the relatively broad spatial and relatively slow temporal scales of the slow shock, one would expect this approximation to be well justified. However, implicit simulations with kinetic electrons have produced significant differences in comparison to standard hybrid results. In this work, we re-examine the importance of electron dynamics to the slow shock using one-dimensional fully kinetic simulations. We employ a simple explicit simulation technique and fully resolve all relevant spatial and temporal electron scales. The resulting shock structure and ion heating are in excellent agreement with hybrid simulations, indicating the total dissipation arising from kinetic electrons is relatively minor. However, the electron heating is somewhat larger than the corresponding hybrid simulation and clear non-Maxwellian features are observed. In the upstream region, back streaming electrons give rise to double peaked distributions while in the downstream region bi-Maxwellian distributions are observed with T{sub e{parallel}} > T{sub e{perpendicular}}.
Date: May 2001
Creator: Daughton, W.; Winske, D. & Yin, L.
Object Type: Article
System: The UNT Digital Library
The structural basis of damaged DNA recognition and endonucleolytic cleavage for Very Short Patch Repair endonuclease (open access)

The structural basis of damaged DNA recognition and endonucleolytic cleavage for Very Short Patch Repair endonuclease

None
Date: May 2, 2001
Creator: Tsutakawa, Susan E. & Morikawa, Kosuke
Object Type: Article
System: The UNT Digital Library
A Simple, Inexpensive in Situ Method for Assessing Acute Toxicity of Effluents to Fish (open access)

A Simple, Inexpensive in Situ Method for Assessing Acute Toxicity of Effluents to Fish

Test chambers for conducting in situ fish bioassays were constructed from 8L polyethylene bottles. Yearling fathead minnows (Pimephales promelas) and young-of-the-year bluegill (Lepomis macrochirus) demonstrated greater than 50 percent survival in the chambers after 65 days of exposure in a reservoir, river, and creek. Fathead minnow survival was substantially greater than that of bluegills. The chambers provide a simple, inexpensive, sensitive technique to screen effluents for toxicity.
Date: May 29, 2001
Creator: Wilde, E.W.
Object Type: Article
System: The UNT Digital Library
SOME CHEMICAL SAFETY ASPECTS AT LANL (open access)

SOME CHEMICAL SAFETY ASPECTS AT LANL

Recently, the Department of Energy (DOE) and its contractors have begun activities to improve the quality and consistency of chemical safety programs throughout the DOE Complex. Several working groups have been formed to assemble a framework for systematically identifying and quantifying chemical hazards and managing chemical risks. At LANL, chemical safety program is implemented through Laboratory Implementation Requirements (LIRs), which are part of the Integrated Safety Management (ISM) plan that includes Safe Work Practices, emphasizing five core functions; define work, identify and analyze hazards, develop and implement controls, perform work safely, and ensure performance. Work is authorized in medium, low and minimal risk areas and not in high risk. Some chemical safety aspects are discussed in terms of chemical hazards and identification, screening, facility hazard categorization--Category A (high), Category B (moderate), and Category C (low), and their requirements in format and content in Authorization Safety Basis documents.
Date: May 1, 2001
Creator: LAUL, J.
Object Type: Article
System: The UNT Digital Library
Linear Collider Physics Resource Book for Snowmass 2001 (open access)

Linear Collider Physics Resource Book for Snowmass 2001

The American particle physics community can look forward to a well-conceived and vital program of experimentation for the next ten years, using both colliders and fixed target beams to study a wide variety of pressing questions. Beyond 2010, these programs will be reaching the end of their expected lives. The CERN LHC will provide an experimental program of the first importance. But beyond the LHC, the American community needs a coherent plan. The Snowmass 2001 Workshop and the deliberations of the HEPAP subpanel offer a rare opportunity to engage the full community in planning our future for the next decade or more. A major accelerator project requires a decade from the beginning of an engineering design to the receipt of the first data. So it is now time to decide whether to begin a new accelerator project that will operate in the years soon after 2010. We believe that the world high-energy physics community needs such a project. With the great promise of discovery in physics at the next energy scale, and with the opportunity for the uncovering of profound insights, we cannot allow our field to contract to a single experimental program at a single laboratory in the world. …
Date: May 3, 2001
Creator: Abe, T.; Dawson, S.; Heinemeyer, S.; Marciano, W.; Paige, F.; Turcot, A. S. et al.
Object Type: Report
System: The UNT Digital Library
A NEW INTERPHASE FORCE IN TWO-PHASE FLUIDIZED BEDS (open access)

A NEW INTERPHASE FORCE IN TWO-PHASE FLUIDIZED BEDS

Mesoscale structures such as particle clusters have been observed both in experiments and in numerical simulations of circulating fluidized beds. In a numerical simulation, in order to account for the effects of such mesoscale structures, the computational grids have to be fine enough. The use of such fine grids is impractical in engineering applications due to excessive computational costs. To predict the macroscopic behavior of a fluidized bed with reasonable computation cost, they perform a second average over the averaged equations for two-phase flows. A mesoscale inter-phase exchange force is found to be the correlation of the particle volume fraction and the pressure gradient. This force is related to the mesoscale added mass of the two-phase flow. Typically, added mass for particle scale interactions is negligible in gas-solid flows since the gas density is small compared to density of solid particles. However, for a mesoscale structure, such as a bubble, the surrounding media is the mixture of gas and particles. The surrounding fluid density experienced by the mesoscale structure is the density of the surrounding mixture. Therefore, the added mass of a mesoscale structure, such as bubbles, cannot be neglected. The property of this new force is studied based on …
Date: May 1, 2001
Creator: ZHANG, D. & VANDERHEYDEN, W.
Object Type: Article
System: The UNT Digital Library
Superresolution and Synthetic Aperture Radar (open access)

Superresolution and Synthetic Aperture Radar

Superresolution concepts offer the potential of resolution beyond the classical limit. This great promise has not generally been realized. In this study we investigate the potential application of superresolution concepts to synthetic aperture radar. The analytical basis for superresolution theory is discussed. The application of the concept to synthetic aperture radar is investigated as an operator inversion problem. Generally, the operator inversion problem is ill posed. A criterion for judging superresolution processing of an image is presented.
Date: May 1, 2001
Creator: Dickey, Fred M.; Romero, Louis & Doerry, Armin W.
Object Type: Report
System: The UNT Digital Library
Comparison of Near-field and Far-field Air Monitoring of Plutonium-contaminated Soils from the Tonopah Test Range, Nevada (open access)

Comparison of Near-field and Far-field Air Monitoring of Plutonium-contaminated Soils from the Tonopah Test Range, Nevada

Operation Roller Coaster, a series of nuclear material dispersal experiments, resulted in three areas (Clean Slates 1, 2, and 3) of widespread surface soil plutonium (Pu) contamination on the Tonopah Test Range (TTR), located 225 miles northwest of Las Vegas, Nevada. The State's Division of Environmental Protection raised concerns that dispersal of airborne Pu particles from the sites could result in undetected deposition further downwind that the background monitoring stations. Air monitoring data from different distances from the Clean Slate sites but during the same period of time were compared. From the available data, there is no indication that airborne PM10 particles are being transported to the farther distance,however, the data are statistically insufficient to conclude whether there is a difference in transport of respirable Pu particles to the closer verses the farther sites from the Clean Slate sites.
Date: May 1, 2001
Creator: Bowen, John L. & Shafer, David S.
Object Type: Report
System: The UNT Digital Library
Hydrogen Generation Rate During Melter Feed Preparation of Tank 42 Sludge and CST in the Defense Waste Processing Facility (open access)

Hydrogen Generation Rate During Melter Feed Preparation of Tank 42 Sludge and CST in the Defense Waste Processing Facility

This document details the testing performed to determine the maximum hydrogen generation expected with a coupled flowsheet of sludge, CST, and frit.
Date: May 2, 2001
Creator: Lambert, D. P. & Monson, P. R.
Object Type: Report
System: The UNT Digital Library
Laboratory Directed Research and Development FY 2000 Annual Progress Report (open access)

Laboratory Directed Research and Development FY 2000 Annual Progress Report

This is the FY00 Annual Progress report for the Laboratory Directed Research and Development (LDRD) Program at Los Alamos National Laboratory. It gives an overview of the LDRD Program, summarizes progress on each project conducted during FY00, characterizes the projects according to their relevance to major funding sources, and provides an index to principal investigators. Project summaries are grouped by LDRD component: Directed Research and Exploratory Research. Within each component, they are further grouped into the ten technical categories: (1) atomic, molecular, optical, and plasma physics, fluids, and beams, (2) bioscience, (3) chemistry, (4) computer science and software engineering, (5) engineering science, (6) geoscience, space science, and astrophysics, (7) instrumentation and diagnostics, (8) materials science, (9) mathematics, simulation, and modeling, and (10) nuclear and particle physics.
Date: May 1, 2001
Creator: Laboratory, Los Alamos National
Object Type: Report
System: The UNT Digital Library
UNCERTAINTY, VALIDATION OF COMPUTER MODELS AND THE MYTH OF NUMERICAL PREDICTABILITY (open access)

UNCERTAINTY, VALIDATION OF COMPUTER MODELS AND THE MYTH OF NUMERICAL PREDICTABILITY

None
Date: May 1, 2001
Creator: HEMEZ, F. M.
Object Type: Article
System: The UNT Digital Library
LES SOFTWARE FOR THE DESIGN OF LOW EMISSION COMBUSTION SYSTEMS FOR VISION 21 PLANTS (open access)

LES SOFTWARE FOR THE DESIGN OF LOW EMISSION COMBUSTION SYSTEMS FOR VISION 21 PLANTS

Further development of a Large Eddy Simulation (LES) code for the design of advanced gaseous combustion systems is described in this second quarterly report. CFD Research Corporation (CFDRC) is developing the LES module within the parallel, unstructured solver included in the commercial CFD-ACE+ software. CFDRC has implemented and tested Smagorinsky and localized dynamic subgrid turbulence models on a 2.1 million cell DOE-NETL combustor case and a 400,000 cell nonreacting backstep case. Both cases showed good agreement between predicted and experimental results. The large DOE-NETL case results provided better agreement with the measured oscillation frequency than previous attempts because massive parallel computing (on a cluster of 24 pcs) allowed the entire computational domain, including the swirler vanes and fuel spokes, to be modeled. Subgrid chemistry models, including the conditional moment closure (CMC) and linear eddy model (LEM), are being tested and implemented. Reduced chemical mechanisms have been developed for emissions, ignition delay, extinction, and flame propagation using a computer automated reduction method (CARM). A 19-species natural gas mechanism, based on GRI2.11 and Miller-NO{sub x}, was shown to predict rich NO{sub x} emissions better than any previously published mechanisms. The ability to handle this mechanism in CFD-ACE+ was demonstrated by implementing operator …
Date: May 1, 2001
Creator: Cannon, Steve; Adumitroaie, Virgil; McDaniel, Keith & Smith, Cliff
Object Type: Report
System: The UNT Digital Library
Small fatigue cracks: mechanics, mechanisms and engineering applications (open access)

Small fatigue cracks: mechanics, mechanisms and engineering applications

Damage-tolerant design and life-prediction methodologies have been practiced for metallic structures for decades, although their application to brittle materials, such as ceramics, and intermetallic alloys, still poses particular problems, primarily because of their extreme flaw-sensitivity.
Date: May 1, 2001
Creator: Ritchie, R. O. & Peters, J. O.
Object Type: Article
System: The UNT Digital Library
WindPACT Turbine Design Scaling Studies Technical Area 3 -- Self-Erecting Tower and Nacelle Feasibility: March 2000--March 2001 (open access)

WindPACT Turbine Design Scaling Studies Technical Area 3 -- Self-Erecting Tower and Nacelle Feasibility: March 2000--March 2001

The United States Department of Energy (DOE), through the National Renewable Energy Laboratory (NREL), has implemented the Wind Partnerships for Advanced Component Technologies (WindPACT) program to explore advanced technologies for improving the reliability and cost-effectiveness of wind energy technology. Global Energy Concepts (GEC) prepared this report on self-erecting towers as part of the WindPACT program. The objectives of the work were to identify potential methods for erecting wind turbine towers without the use of large conventional cranes, establish the most promising methods, and compare the costs of the most promising methods to the costs of conventional cranes.
Date: May 31, 2001
Creator: Global Energy Concepts, LLC
Object Type: Report
System: The UNT Digital Library
STRUCTURAL HEALTH MONITORING OF WELDED CONNECTIONS (open access)

STRUCTURAL HEALTH MONITORING OF WELDED CONNECTIONS

Structural health monitoring is the implementation of a damage detection strategy for aerospace, civil and mechanical engineering infrastructure. Typical damage experienced by this infrastructure might be the development of fatigue cracks, degradation of structural connections, or bearing wear in rotating machinery. The goal of the research effort reported herein is to develop a robust and cost-effective monitoring system for welded beam-column connections in a moment resisting frame structure. The structural health monitoring solution for this application will integrate structural dynamics, wireless data acquisition, local actuation, micro-electromechanical systems (MEMs) technology, and statistical pattern recognition algorithms. This paper provides an example of the integrated approach to structural health monitoring being undertaken at Los Alamos National Laboratory and summarizes progress to date on various aspects of the technology development.
Date: May 1, 2001
Creator: SOHN, H.; FARRAR, C.; FUGATE, M. & CZARNECKI, J.
Object Type: Article
System: The UNT Digital Library
Field Verification Program for Small Wind Turbines, Quarterly Report: 3rd Quarter, Issue No.2, July-September 2000 (open access)

Field Verification Program for Small Wind Turbines, Quarterly Report: 3rd Quarter, Issue No.2, July-September 2000

This newsletter provides a brief overview of the Field Verification Program for Small Wind Turbines conducted out of the NWTC and a description of current activities. The newsletter also contains case studies of current projects.
Date: May 16, 2001
Creator: J., Cardinal. & Tu, P.
Object Type: Report
System: The UNT Digital Library
VITRIFICATION SYSTEM FOR THE TREATMENT OF PLUTONIUM-BEARING WASTE AT LOS ALAMOS NATIONAL LABORATORY (open access)

VITRIFICATION SYSTEM FOR THE TREATMENT OF PLUTONIUM-BEARING WASTE AT LOS ALAMOS NATIONAL LABORATORY

A glove box vitrification system is being fabricated to process aqueous evaporator bottom waste generated at the Plutonium Facility (TA-55) at Los Alamos National Laboratory (LANL). The system will be the first within the U.S. Department of Energy Complex to routinely convert Pu{sup 239}-bearing transuranic (TRU) waste to a glass matrix for eventual disposal at the Waste Isolation Pilot Plant (WIPP). Currently at LANL, this waste is solidified in Portland cement. Radionuclide loading in the cementation process is restricted by potential radiolytic degradation (expressed as a wattage limit), which has been imposed to prevent the accumulation of flammable concentrations of H{sub 2} within waste packages. Waste matrixes with a higher water content (e.g., cement) are assigned a lower permissible wattage limit to compensate for their potential higher generation of H{sub 2}. This significantly increases the number of waste packages that must be prepared and shipped, thus driving up the costs of waste handling and disposal. The glove box vitrification system that is under construction will address this limitation. Because the resultant glass matrix produced by the vitrification process is non-hydrogenous, no H{sub 2} can be radiolytically evolved, and drums could be loaded to the maximum allowable limit of 40 watts. …
Date: May 1, 2001
Creator: NAKAOKA, R.; VEAZEY, G. & AL, ET
Object Type: Article
System: The UNT Digital Library
Corn Stover for Bioethanol -- Your New Cash Crop? (open access)

Corn Stover for Bioethanol -- Your New Cash Crop?

Biomass ethanol technology is still developing and important questions need to be answered about corn stover removal, but prospects are excellent for you to someday be able to harvest and sell a substantial portion of your stover for fuel production--without hurting your soil or main corn grain operation.
Date: May 16, 2001
Creator: Brown, H.
Object Type: Book
System: The UNT Digital Library
Collisionless relaxation in beam-plasma systems (open access)

Collisionless relaxation in beam-plasma systems

This thesis reports the results from the theoretical investigations, both numerical and analytical, of collisionless relaxation phenomena in beam-plasma systems. Many results of this work can also be applied to other lossless systems of plasma physics, beam physics and astrophysics. Different aspects of the physics of collisionless relaxation and its modeling are addressed. A new theoretical framework, named Coupled Moment Equations (CME), is derived and used in numerical and analytical studies of the relaxation of second order moments such as beam size and emittance oscillations. This technique extends the well-known envelope equation formalism, and it can be applied to general systems with nonlinear forces. It is based on a systematic moment expansion of the Vlasov equation. In contrast to the envelope equation, which is derived assuming constant rms beam emittance, the CME model allows the emittance to vary through coupling to higher order moments. The CME model is implemented in slab geometry in the absence of return currents. The CME simulation yields rms beam sizes, velocity spreads and emittances that are in good agreement with particle-in-cell (PIC) simulations for a wide range of system parameters. The mechanism of relaxation is also considered within the framework of the CME system. It …
Date: May 1, 2001
Creator: Backhaus, Ekaterina Yu.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Critical Experiments With Aqueous Solutions of {sup 233}UO{sub 2}(NO{sub ;3}){sub 2} (open access)

Critical Experiments With Aqueous Solutions of {sup 233}UO{sub 2}(NO{sub ;3}){sub 2}

This report provides the critical experimenter's interpretations and descriptions of informal critical experiment logbook notes and associated information (e.g., experimental equipment designs/sketches, chemical and isotopic analyses, etc.) for the purpose of formally documenting the results of critical experiments performed in the late 1960s at the Oak Ridge Critical Experiments Facility. The experiments were conducted with aqueous solutions of 97.6 wt % {sup 233}U uranyl nitrate having uranium densities varying between about 346 g U/l and 45 g U/l. Criticality was achieved with single simple units (e.g., cylinders and spheres) and with spaced subcritical simple cylindrical units arranged in unreflected, water-reflected, and polyethylene reflected critical arrays.
Date: May 17, 2001
Creator: Thomas, J.T.
Object Type: Report
System: The UNT Digital Library