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Surface Treatment of a Lithium Limiter for Spherical Torus Plasma Experiments (open access)

Surface Treatment of a Lithium Limiter for Spherical Torus Plasma Experiments

The concept of a flowing lithium first wall for a fusion reactor may lead to a significant advance in reactor design, since it could virtually eliminate the concerns with power density and erosion, tritium retention, and cooling associated with solid walls. As part of investigations to determine the feasibility of this approach, plasma interaction questions in a toroidal plasma geometry are being addressed in the Current Drive eXperiment-Upgrade (CDX-U) spherical torus (ST). The first experiments involved a toroidally local lithium limiter (L3). Measurements of pumpout rates indicated that deuterium pumping was greater for the L3 compared to conventional boron carbide limiters. The difference in the pumpout rates between the two limiter types decreased with plasma exposure, but argon glow discharge cleaning was able to restore the pumping effectiveness of the L3. At no point, however, was the extremely low recycling regime reported in previous lithium experiments achieved. This may be due to the much larger lithium surfaces that were exposed to the plasma in the earlier work. The possibility will be studied in the next set of CDX-U experiments, which are to be conducted with a large area, fully toroidal lithium limiter.
Date: March 20, 2001
Creator: Kaita, R.; Majeski, R.; Doerner, R.; Antar, G.; Timberlake, J.; Spaleta, J. et al.
System: The UNT Digital Library
Analysis of mineral trapping for CO{sub 2} disposal in deep aquifers (open access)

Analysis of mineral trapping for CO{sub 2} disposal in deep aquifers

CO{sub 2} disposal into deep aquifers has been suggested as a potential means whereby atmospheric emissions of greenhouse gases may be reduced. However, our knowledge of the geohydrology, geochemistry, geophysics, and geomechanics of CO{sub 2} disposal must be refined if this technology is to be implemented safely, efficiently, and predictably. As a prelude to a fully coupled treatment of physical and chemical effects of CO{sub 2} injection, we have analyzed the impact of CO{sub 2} immobilization through carbonate precipitation. A survey of all major classes of rock-forming minerals, whose alteration would lead to carbonate precipitation, indicated that very few minerals are present in sufficient quantities in aquifer host rocks to permit significant sequestration of CO{sub 2}. We performed batch reaction modeling of the geochemical evolution of three different aquifer mineralogies in the presence of CO{sub 2} at high pressure. Our modeling considered (1) redox processes that could be important in deep subsurface environments, (2) the presence of organic matter, (3) the kinetics of chemical interactions between the host rock minerals and the aqueous phase, and (4) CO{sub 2} solubility dependence on pressure, temperature and salinity of the system. The geochemical evolution under both natural background and CO{sub 2} injection conditions …
Date: July 20, 2001
Creator: Xu, Tianfu; Apps, John A. & Pruess, Karsten
System: The UNT Digital Library
The Status of Radiation Damage Experiments (open access)

The Status of Radiation Damage Experiments

Experiments have been on-going for about two years to determine the effects that radiation damage have on the physical and chemical properties of candidate titanate ceramics for the immobilization of plutonium. We summarize the results of these experiments in this document.
Date: November 20, 2001
Creator: Strachan, Denis M; Scheele, Randall D; Icenhower, Jonathan P; Kozelisky, Anne E; Sell, Richard L; Legore, Virginia L et al.
System: The UNT Digital Library
Coupling of MASH-MORSE Adjoint Leakages with Space- and Time-Dependent Plume Radiation Sources (open access)

Coupling of MASH-MORSE Adjoint Leakages with Space- and Time-Dependent Plume Radiation Sources

In the past, forward-adjoint coupling procedures in air-over-ground geometry have typically involved forward fluences arising from a point source a great distance from a target or vehicle system. Various processing codes were used to create localized forward fluence files that could be used to couple with the MASH-MORSE adjoint leakages. In recent years, radiation plumes that result from reactor accidents or similar incidents have been modeled by others, and the source space and energy distributions as a function of time have been calculated. Additionally, with the point kernel method, they were able to calculate in relatively quick fashion free-field radiation doses for targets moving within the fluence field or for stationary targets within the field, the time dependence for the latter case coming from the changes in position, shape, source strength, and spectra of the plume with time. The work described herein applies the plume source to the MASH-MORSE coupling procedure. The plume source replaces the point source for generating the forward fluences that are folded with MASH-MORSE adjoint leakages. Two types of source calculations are described. The first is a ''rigorous'' calculation using the TORT code and a spatially large air-over-ground geometry. For each time step desired, directional fluences …
Date: April 20, 2001
Creator: Slater, C. O.
System: The UNT Digital Library
Vadose Zone Remediation Assessment: M-Area Process Sewer Soil Vapor Extraction Units 782-5M, 782-7M, and 782-8M (open access)

Vadose Zone Remediation Assessment: M-Area Process Sewer Soil Vapor Extraction Units 782-5M, 782-7M, and 782-8M

This study focuses on the status of the vadose zone remediation along 1600 ft of the process sewer line between the M-Area security fence and the M-Area settling basin. Three soil vapor extraction (SVE) units 782-5M, 782-7M, and 782-8M, connected to 4 vertical wells and 3 horizontal wells have been addressing the vadose zone volatile organic contamination (VOC) since 1995. The specific objectives of this study were to obtain soil gas and sediment samples, evaluate SVE units and vadose zone remediation, and make recommendations to address further remediation needs.
Date: April 20, 2001
Creator: Riha, B. D.
System: The UNT Digital Library
Instream Biological Assessment of NPDES Point Source Discharges at the Savannah River Site, 2000 (open access)

Instream Biological Assessment of NPDES Point Source Discharges at the Savannah River Site, 2000

The Savannah River Site (SRS) currently has 31 NPDES outfalls that have been permitted by the South Carolina Department of Health and Environmental Control (SCDHEC) to discharge to SRS streams and the Savannah River. In order to determine the cumulative impacts of these discharges to the receiving streams, a study plan was developed to perform in-stream assessments of the fish assemblages, macroinvertebrate assemblages, and habitats of the receiving streams. These studies were designed to detect biological impacts due to point source discharges. Sampling was initially conducted between November 1997 and July 1998 and was repeated in the summer and fall of 2000. A total of 18 locations were sampled (Table 1, Figure 1). Sampling locations for fish and macroinvertebrates were generally the same. However, different locations were sampled for fish (Road A-2) and macroinvertebrates (Road C) in the lower portion of Upper Three Runs, to avoid interference with ongoing fisheries studies at Road C. Also, fish were sampled in Fourmile Branch at Road 4 rather than at Road F because the stream at Road F was too narrow and shallow to support many fish. Sampling locations and parameters are detailed in Sections 2 and 3 of this report. In general, …
Date: June 20, 2001
Creator: Specht, Winona L.
System: The UNT Digital Library
Test Results for Implementation of Hydrogen Getter in the DDF-1 Shipping Package (open access)

Test Results for Implementation of Hydrogen Getter in the DDF-1 Shipping Package

Implementation of a hydrogen getter for transportation of radioactive materials in the DDF-1 shipping package will support onsite transfers of radioactive materials without extensive characterization or moisture analysis.
Date: June 20, 2001
Creator: Livingston, R.R.
System: The UNT Digital Library
Betatron tune shifts and Laslett image coefficients (open access)

Betatron tune shifts and Laslett image coefficients

The complicated expressions of betatron tune shifts in terms of Laslett image coefficients are explained. The expressions of image coefficients for a centered or off-centered beam inside an elliptical or rectangular vacuum chamber are gathered. Typos in earlier literature are corrected.
Date: July 20, 2001
Creator: Ng, K. Y.
System: The UNT Digital Library
OPTIMIZATION OF COAL PARTICLE FLOW PATTERNS IN LOW NOX BURNERS (open access)

OPTIMIZATION OF COAL PARTICLE FLOW PATTERNS IN LOW NOX BURNERS

The proposed research is directed at evaluating the effect of flame aerodynamics on NO{sub x} emissions from coal fired burners in a systematic manner. This fundamental research includes both experimental and modeling efforts being performed at the University of Arizona in collaboration with Purdue University. The objective of this effort is to develop rational design tools for optimizing low NO{sub x} burners to the kinetic emissions limit (below 0.2 lb./MMBTU). Experimental studies include both cold and hot flow evaluations of the following parameters: flame holder geometry, secondary air swirl, primary and secondary inlet air velocity, coal concentration in the primary air and coal particle size distribution. Hot flow experiments will also evaluate the effect of wall temperature on burner performance. Cold flow studies will be conducted with surrogate particles as well as pulverized coal. The cold flow furnace will be similar in size and geometry to the hot-flow furnace but will be designed to use a laser Doppler velocimeter/phase Doppler particle size analyzer. The results of these studies will be used to predict particle trajectories in the hot-flow furnace as well as to estimate the effect of flame holder geometry on furnace flow field. The hot-flow experiments will be conducted …
Date: August 20, 2001
Creator: Wendt, Jost O.L.; Ogden, Gregory E.; Sinclair, Jennifer & Yurteri, Caner
System: The UNT Digital Library
Beam tube vacuum in a Very Large Hadron Collider; Stage 1 VLHC (open access)

Beam tube vacuum in a Very Large Hadron Collider; Stage 1 VLHC

Synchrotron radiation induced photodesorption in particle accelerators may lead to pressure rise and to beam-gas scattering losses, finally affecting the beam lifetime. We discuss the beam tube vacuum in the low field Stage 1 Very Large Hadron Collider VLHC. Since VLHC Stage 1 has a room temperature beam tube, a non-evaporable getter (NEG St101 strip) pumping system located inside a pumping antechamber, supplemented by lumped ion pumps for pumping methane is considered. A possible beam conditioning scenario is presented for reaching design intensity. The most important results are summarized in this paper. More detailed reports of the calculations will be presented at the PAC2001 Conference, Chicago, IL to be held in June 2001, and at the Snowmass Conference, CO, to be held on July 2001.
Date: April 20, 2001
Creator: Pivi, M. & Turner, W.C.
System: The UNT Digital Library
OPTIMIZATION OF COAL PARTICLE FLOW PATTERNS IN LOW NOX BURNERS (open access)

OPTIMIZATION OF COAL PARTICLE FLOW PATTERNS IN LOW NOX BURNERS

The proposed research is directed at evaluating the effect of flame aerodynamics on NO{sub x} emissions from coal fired burners in a systematic manner. This fundamental research includes both experimental and modeling efforts being performed at the University of Arizona in collaboration with Purdue University. The objective of this effort is to develop rational design tools for optimizing low NO{sub x} burners to the kinetic emissions limit (below 0.2 lb./MMBTU). Experimental studies include both cold and hot flow evaluations of the following parameters: flame holder geometry, secondary air swirl, primary and secondary inlet air velocity, coal concentration in the primary air and coal particle size distribution. Hot flow experiments will also evaluate the effect of wall temperature on burner performance. Cold flow studies will be conducted with surrogate particles as well as pulverized coal. The cold flow furnace will be similar in size and geometry to the hot-flow furnace but will be designed to use a laser Doppler velocimeter/phase Doppler particle size analyzer. The results of these studies will be used to predict particle trajectories in the hot-flow furnace as well as to estimate the effect of flame holder geometry on furnace flow field. The hot-flow experiments will be conducted …
Date: August 20, 2001
Creator: Wendt, Jost O.L.; Ogden, Gregory E.; Sinclair, Jennifer & Budilarto, Stephanus
System: The UNT Digital Library
Bonneville Second Powerhouse Tailrace and High Flow Outfall: ADCP and drogue release field study (open access)

Bonneville Second Powerhouse Tailrace and High Flow Outfall: ADCP and drogue release field study

The Bonneville Project is one of four US Army Corps of Engineers operated dams along the Lower Columbia River. Each year thousands of smelt pass through this Project on their way to the Pacific Ocean. High flow outfalls, if specifically designed for fish passage, are thought to have as good or better smelt survival rates as spillways. To better understand the hydrodynamic flow field around an operating outfall, the Corps of Engineers commissioned measurement of water velocities in the tailrace of the Second Powerhouse. These data also are necessary for proper calibration and verification of three-dimensional numerical models currently under development at PNNL. Hydrodynamic characterization of the tailrace with and without the outfall operating was accomplished through use of a surface drogue and acoustic Doppler current profiler (ADCP). Both the ADCP and drogue were linked to a GPS (global positioning system); locating the data in both space and time. Measurements focused on the area nearest to the high flow outfall, however several ADCP transects and drogue releases were performed away from the outfall to document ambient flow field conditions when the outfall was not operating.
Date: March 20, 2001
Creator: Cook, Chris B; Richmond, Marshall C & Guensch, Greg
System: The UNT Digital Library
Radionuclide Transport Models Under Ambient Conditions (open access)

Radionuclide Transport Models Under Ambient Conditions

The purpose of Revision 00 of this Analysis/Model Report (AMR) is to evaluate (by means of 2-D semianalytical and 3-D numerical models) the transport of radioactive solutes and colloids in the unsaturated zone (UZ) under ambient conditions from the potential repository horizon to the water table at Yucca Mountain (YM), Nevada.
Date: December 20, 2001
Creator: Moridis, G. & Hu, Q.
System: The UNT Digital Library
PRODUCTION OF NEW BIOMASS/WASTE-CONTAINING SOLID FUELS (open access)

PRODUCTION OF NEW BIOMASS/WASTE-CONTAINING SOLID FUELS

CQ Inc. and its team members (ALSTOM Power Inc., Bliss Industries, McFadden Machine Company, and industry advisors from coal-burning utilities, equipment manufacturers, and the pellet fuels industry) addressed the objectives of the Department of Energy and industry to produce economical, new solid fuels from coal, biomass, and waste materials that reduce emissions from coal-fired boilers. This project builds on the team's commercial experience in composite fuels for energy production. The electric utility industry is interested in the use of biomass and wastes as fuel to reduce both emissions and fuel costs. In addition to these benefits, utilities also recognize the business advantage of consuming the waste byproducts of customers both to retain customers and to improve the public image of the industry. Unfortunately, biomass and waste byproducts can be troublesome fuels because of low bulk density, high moisture content, variable composition, handling and feeding problems, and inadequate information about combustion and emissions characteristics. Current methods of co-firing biomass and wastes either use a separate fuel receiving, storage, and boiler feed system, or mass burn the biomass by simply mixing it with coal on the storage pile. For biomass or biomass-containing composite fuels to be extensively used in the U.S., especially …
Date: April 20, 2001
Creator: Akers, David J.; Shirey, Glenn A.; Zitron, Zalman & Maney, Charles Q.
System: The UNT Digital Library
OZONE TREATMENT OF SOLUBLE ORGANICS IN PRODUCED WATER (FEAC307) (open access)

OZONE TREATMENT OF SOLUBLE ORGANICS IN PRODUCED WATER (FEAC307)

Oil production is shifting from ''shallow'' wells (0-650 ft water depth) to off-shore, deep-water operations (>2,600 ft.). Production from these operations is now approaching 20%. By 2007, it is projected that as much as 70% of the U.S. oil production will be from deep-water operations. The crude oil from these deep wells is more polar, thus increasing the amount of dissolved hydrocarbons in the produced water. Early data from Gulf of Mexico (GOM) wells indicate that the problem with soluble organics will increase significantly as deep-water production increases. Existing physical/chemical treatment technologies used to remove dispersed oil from produced water will not remove dissolved organics. GOM operations are rapidly moving toward design of high-capacity platforms that will require compact, low-cost, efficient treatment processes to comply with current and future water quality regulations. This project is an extension of previous research to improve the applicability of ozonation and will help address the petroleum industry-wide problem of treating water containing soluble organics. The goal of this project is to maximize oxidation of water-soluble organics during a single-pass operation. The project investigates: (1) oxidant production by electrochemical and sonochemical methods, (2) increasing the mass transfer rate in the reactor by forming microbubbles during …
Date: March 20, 2001
Creator: Klasson, KT
System: The UNT Digital Library
Vertical Distribution of Calcite at Yucca Mountain, Nevada, as an Indicator of Flow Through a Thick Unsaturated Zone (open access)

Vertical Distribution of Calcite at Yucca Mountain, Nevada, as an Indicator of Flow Through a Thick Unsaturated Zone

Meteoric water percolating through 500 to 700 m of hydrologically unsaturated felsic tuffs provides a mechanism for release and transport of radionuclides from a potential high-level radioactive waste repository at Yucca Mountain, Nevada. Modern flow through the unsaturated zone (UZ) is low (probably <20 mm/year) and has not been observed directly. However, calcite formed from water percolating through fracture and lithophysal cavities over the last 12.8 million years provides, in part, a time-integrated record of UZ flow. Calcite concentration profiles were determined in dry-drilled boreholes USW WT-24 and USW SD-6 by acidifying samples of powdered rock cuttings collected over 5-foot intervals and measuring the evolved CO{sub 2} using gas chromatography. Resulting CO{sub 2}-derived calcite concentrations ranged from 30,800 to less than 20 ppm. Aliquots of the same powders also were analyzed for Ca, Ti, and Zr by energy-dispersive X-ray fluorescence. Concentrations of Ti and Zr in the crystal-poor, high-silica rhyolite parts of the Topopah Spring Tuff are uniform (standard deviations of 3 to 4%); however, Ca scatters widely (standard deviations of 21 and 32%). Concentrations of Ca are positively correlated to CO{sub 2}-derived calcite concentrations and regressions for samples of the two major rhyolitic tuffs yielded r{sup 2} values >0.9, …
Date: July 20, 2001
Creator: Paces, J. B. & Peterman, Z. E.
System: The UNT Digital Library
Individuals with Disabilities Education Act (IDEA): Identification and Misidentification of Children with Disabilities (open access)

Individuals with Disabilities Education Act (IDEA): Identification and Misidentification of Children with Disabilities

This report discusses issues related to the identification and misidentification of children with disabilities.
Date: November 20, 2001
Creator: Apling, Richard N.
System: The UNT Digital Library
Voting in the Senate: Forms and Requirements (open access)

Voting in the Senate: Forms and Requirements

This report contains the different forms and requirements to vote in the Senate.
Date: February 20, 2001
Creator: Oleszek, Walter J.
System: The UNT Digital Library
Decay Heat of Major Radionuclides for PWR Spent Fuels to 10,000 Years (open access)

Decay Heat of Major Radionuclides for PWR Spent Fuels to 10,000 Years

The objective of this calculation is to determine decay heat of a pressurized-water reactor (PWR) spent nuclear fuel (SNF) assembly with four different initial-enrichment and burnup characteristics. The major contributing radionuclides to the decay heat are also identified and graphically presented. The scope of this calculation is limited to the time period of the first 10,000 years after discharge from reactors. The results of this calculation will be used to evaluate the effects of the projected commercial spent nuclear fuel (CSNF) inventory on the repository design based on revised nuclear energy forecasts. This calculation was performed in accordance with the ''Technical Work Plan for: Waste Package Design Description for LA'' (BSC (Bechtel SAIC Company) 2001). AP-3.12Q, Calculations, is used to perform the calculation and develop the document. This calculation is associated with the repository design activity.
Date: December 20, 2001
Creator: Tang, Jabo S.
System: The UNT Digital Library
Building and measuring a high performance network architecture (open access)

Building and measuring a high performance network architecture

Once a year, the SC conferences present a unique opportunity to create and build one of the most complex and highest performance networks in the world. At SC2000, large-scale and complex local and wide area networking connections were demonstrated, including large-scale distributed applications running on different architectures. This project was designed to use the unique opportunity presented at SC2000 to create a testbed network environment and then use that network to demonstrate and evaluate high performance computational and communication applications. This testbed was designed to incorporate many interoperable systems and services and was designed for measurement from the very beginning. The end results were key insights into how to use novel, high performance networking technologies and to accumulate measurements that will give insights into the networks of the future.
Date: April 20, 2001
Creator: Kramer, William T.C.; Toole, Timothy; Fisher, Chuck; Dugan, Jon; Wheeler, David; Wing, William R et al.
System: The UNT Digital Library
Supplemental Appropriations for FY2002: Defense Readiness and Other Programs (open access)

Supplemental Appropriations for FY2002: Defense Readiness and Other Programs

None
Date: July 20, 2001
Creator: Daggett, Stephen
System: The UNT Digital Library
Jordan: U.S. Relations and Bilateral Issues (open access)

Jordan: U.S. Relations and Bilateral Issues

None
Date: November 20, 2001
Creator: Prados, Alfred B.
System: The UNT Digital Library
Iraq-U.S. Confrontation (open access)

Iraq-U.S. Confrontation

None
Date: November 20, 2001
Creator: Prados, Alfred B. & Katzman, Kenneth
System: The UNT Digital Library
Cuba: Issues for Congress (open access)

Cuba: Issues for Congress

This report examines the economic and political situation in Cuba, including the human rights situation, and U.S. policy toward Cuba. The report also analyzes a number of issues facing Congress in U.S. policy toward Cuba, including: the overall direction of U.S. policy; challenges to U.S. policy in the World Trade Organization; restrictions on commercial food and medical exports; restrictions on travel; bilateral drug trafficking cooperation; Cuba and terrorism; funding for U.S.-government sponsored radio and television broadcasting to Cuba; the Russian signals intelligence facility in Cuba; migration issues; and compensation to the families of those Americans killed in 1996 when Cuba shot down two U.S. civilian planes. The report cites legislation that was passed in the 106th Congress, and also tracks legislative action on these various issues in U.S. policy toward Cuba in the 107th Congress.
Date: November 20, 2001
Creator: Sullivan, Mark P. & Taft-Morales, Maureen
System: The UNT Digital Library