Resource Type

EBW PHYSICS OF ECE IN NSTX (open access)

EBW PHYSICS OF ECE IN NSTX

Topics covered include: ray tracing and Fokker-Planck coupling; relativistic and electromagnetic effects in EBW damping (ray-tracing); O-X-EBW mode conversion efficiency limit due to finite beam divergence; general prospects for electron Bernstein wave heating and current drive in spherical tokamaks; sensitivity of EBW H&CD; collisional effects on EBW coupling; and EBW propagation in a high-temperature plasma.
Date: June 26, 2012
Creator: Vahala, Linda
System: The UNT Digital Library
Categorization of Radioxenon (open access)

Categorization of Radioxenon

This report summarizes a study into some false positive issues in the use of radioxenon as a method to verify a clandestine nuclear weapons explosion. False positives arise due to similarities between the radioxenon signature generated in medical isotope production and that generated in a nuclear weapon explosion. This report also discusses how to categorize the radioxenon by levels of urgency for manual analysis and interpretation and recommends applying machine learning and time series analysis techniques in the automation of radioxenon characterization. The literature indicates that medical isotope production is a major contributor to atmospheric radioxenon and is the main source of confusion in determining the source of radioxenon. While radioxenon emissions from nuclear power plants can be distinguished from that from nuclear weapon explosions, emissions from medical isotope production generate signatures similar to certain nuclide ratios found in nuclear weapons explosions. Different techniques for analyzing nuclide concentrations and ratios as well as including other sensing modalities via sensor fusion are discussed.
Date: April 26, 2012
Creator: Keller, Paul E.
System: The UNT Digital Library
PLUTONIUM LOADING CAPACITY OF REILLEX HPQ ANION EXCHANGE COLUMN - AFS-2 PLUTONIUM FLOWSHEET FOR MOX (open access)

PLUTONIUM LOADING CAPACITY OF REILLEX HPQ ANION EXCHANGE COLUMN - AFS-2 PLUTONIUM FLOWSHEET FOR MOX

Radioactive plutonium (Pu) anion exchange column experiments using scaled HB-Line designs were performed to investigate the dependence of column loading performance on the feed composition in the H-Canyon dissolution process for plutonium oxide (PuO{sub 2}) product shipped to the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). These loading experiments show that a representative feed solution containing {approx}5 g Pu/L can be loaded onto Reillex{trademark} HPQ resin from solutions containing 8 M total nitrate and 0.1 M KF provided that the F is complexed with Al to an [Al]/[F] molar ratio range of 1.5-2.0. Lower concentrations of total nitrate and [Al]/[F] molar ratios may still have acceptable performance but were not tested in this study. Loading and washing Pu losses should be relatively low (<1%) for resin loading of up to 60 g Pu/L. Loading above 60 g Pu/L resin is possible, but Pu wash losses will increase such that 10-20% of the additional Pu fed may not be retained by the resin as the resin loading approaches 80 g Pu/L resin.
Date: July 26, 2012
Creator: Kyser, E.; King, W. & O'Rourke, P.
System: The UNT Digital Library
Annual Report of Monitoring at Barnes, Kansas, in 2011. (open access)

Annual Report of Monitoring at Barnes, Kansas, in 2011.

Barnes, Kansas, is a small rural community (population approximately 150) located in Washington County, in north-central Kansas (Figure 1.1). The city lies in a transition zone between the Flint Hills and the glaciated region. The area's topography consists of gently sloping hills of Pleistocene loess (< 20 ft) overlying a shale unit and interbedded shale, limestone, and siltstone of the Permian Chase Group. Groundwater for the public water supply is obtained from wells PWS2 and PWS3 at reported depths of 155 ft and 160 ft, respectively, located in the northwestern portion of the city. The water is produced from the bedrock aquifer of the Chase Group. Section 2 summarizes of the hydrogeologic conceptual site model. The findings of the monitoring events at Barnes in 2011 continued to support the following previous conclusions: (1) Measurements of groundwater levels obtained manually and through the use of automatic recorders have consistently indicated that the flow direction is strongly influenced by pumping of the public water supply wells. The results have demonstrated an apparent groundwater flow direction to the northeast when the public wells are not pumping and a northwesterly groundwater flow trend when the public wells are pumping. (2) Evaluation of manual water …
Date: July 26, 2012
Creator: LaFreniere, L. M.
System: The UNT Digital Library
Tidal Energy System for On-Shore Power Generation (open access)

Tidal Energy System for On-Shore Power Generation

Addressing the urgent need to develop LCOE competitive renewable energy solutions for US energy security and to replace fossil-fuel generation with the associated benefits to environment impacts including a reduction in CO2 emissions, this Project focused on the advantages of using hydraulic energy transfer (HET) in large-scale Marine Hydrokinetic (MHK) systems for harvesting off-shore tidal energy in US waters. A recent DOE resource assessment, identifies water power resources have a potential to meet 15% of the US electric supply by 2030, with MHK technologies being a major component. The work covered a TRL-4 laboratory proof-in-concept demonstration plus modeling of a 15MW full scale system based on an approach patented by NASA-JPL, in which submerged high-ratio gearboxes and electrical generators in conventional MHK turbine systems are replaced by a submerged hydraulic radial pump coupled to on-shore hydraulic motors driving a generator. The advantages are; first, the mean-time-between-failure (MTBF), or maintenance, can be extended from approximately 1 to 5 years and second, the range of tidal flow speeds which can be efficiently harvested can be extended beyond that of a conventional submerged generator. The approach uses scalable, commercial-off-the-shelf (COTS) components, facilitating scale-up and commercialization. All the objectives of the Project have been …
Date: June 26, 2012
Creator: Bruce, Allan J
System: The UNT Digital Library
Geothermal Exploration in Hot Springs, Montana (open access)

Geothermal Exploration in Hot Springs, Montana

The project involves drilling deeper in the Camp Aqua well dri lled in June 1982 as part of an effort to develop an ethanol plant. The purpose of the current drill ing effort is to determine if water at or above 165°F exists for the use in low temperature resource power generation. Previous geothermal resource study efforts in and around Hot Springs , MT and the Camp Aqua area (NE of Hot Springs) have been conducted through the years. A confined gravel aquifer exists in deep alluvium overlain by approximately 250’ of si lt and c lay deposits from Glacial Lake Missoula. This gravel aquifer overlies a deeper bedrock aquifer. In the Camp Aqua area several wel l s exist in the gravel aquifer which receives hot water f rom bedrock fractures beneath the area. Prior to this exploration, one known well in the Camp Aqua area penetrated into the bedrock without success in intersecting fractures transporting hot geothermal water. The exploration associated with this project adds to the physical knowledge database of the Camp Aqua area. The dri l l ing effort provides additional subsurface information that can be used to gain a better understanding of the bedrock formation …
Date: September 26, 2012
Creator: Toby McIntosh, Jackola Engineering
System: The UNT Digital Library
Wind Turbine Manufacturing Process Monitoring (open access)

Wind Turbine Manufacturing Process Monitoring

To develop a practical inline inspection that could be used in combination with automated composite material placement equipment to economically manufacture high performance and reliable carbon composite wind turbine blade spar caps. The approach technical feasibility and cost benefit will be assessed to provide a solid basis for further development and implementation in the wind turbine industry. The program is focused on the following technology development: (1) Develop in-line monitoring methods, using optical metrology and ultrasound inspection, and perform a demonstration in the lab. This includes development of the approach and performing appropriate demonstration in the lab; (2) Develop methods to predict composite strength reduction due to defects; and (3) Develop process models to predict defects from leading indicators found in the uncured composites.
Date: April 26, 2012
Creator: Faidi, Waseem; Nafis, Chris; Sinha, Shatil; Yerramalli, Chandra; Waas, Anthony; Advani, Suresh et al.
System: The UNT Digital Library
Effects and Mechanisms of Mechanical Activation on Hydrogen Sorption/ Desorption of Nanoscale Lithium Nitrides (open access)

Effects and Mechanisms of Mechanical Activation on Hydrogen Sorption/ Desorption of Nanoscale Lithium Nitrides

The objective of this project is to investigate and develop novel, mechanically activated, nanoscale Li3N-based and LiBH4-based materials that are able to store and release {approx}10 wt% hydrogen at temperatures near 100 C with a plateau hydrogen pressure of less than 10 bar. Four (4) material systems have been investigated in the course of this project in order to achieve the project objective. These 4 systems are (i) LiNH2+LiH, (ii) LiNH2+MgH2, (iii) LiBH4, and (iv) LiBH4+MgH2. The key findings we have obtained from these 4 systems are summarized below. *The thermodynamic driving forces for LiNH2+LiH and LiBH4 systems are not adequate to enable H2 release at temperatures < 100 C. *Hydrogen release in the solid state for all of the four systems is controlled by diffusion, and thus is a slow process. *LiNH2+MgH2 and LiBH4+MgH2 systems, although possessing proper thermodynamic driving forces to allow for H2 release at temperatures < 100 C, have sluggish reaction kinetics because of their diffusion-controlled rate-limiting steps. *Reducing particles to the nanometer length scale (< 50 nm) can improve the thermodynamic driving force to enable H2 release at near ambient temperature, while simultaneously enhancing the reaction kinetics as well as changing the diffusion-controlled rate-limiting step …
Date: April 26, 2012
Creator: Shaw, Leon, L.; Yang, Gary, Z.; Crosby, Kyle; Wwan, Xufei. Zhong, Yang; Markmaitree, Tippawan; Osborn, William et al.
System: The UNT Digital Library
Plasma Synthesized Doped Boron Nanopowder for MgB2 Superconductors (open access)

Plasma Synthesized Doped Boron Nanopowder for MgB2 Superconductors

Under this program, a process to synthesize nano-sized doped boron powder by a plasma synthesis process was developed and scaled up from 20 gram batches at program start to over 200 grams by program end. Over 75 batches of boron nanopowder were made by RF plasma synthesis. Particle sizes were typically in the 20-200 nm range. The powder was synthesized by the reductive pyrolysis of BCl{sub 3} in hydrogen in an RF plasma. A wide range of process parameters were investigated including plasma power, torch geometry, gas flow rates, and process pressure. The powder-in-tube technique was used to make monofilament and multifilament superconducting wires. MgB{sub 2} wire made with Specialty Materials plasma synthesized boron nanopowder exhibited superconducting properties that significantly exceeded the program goals. Superconducting critical currents, J{sub c}, in excess of 10{sup 5} A cm{sup -2} at magnetic fields of 8 tesla were reproducibly achieved. The upper critical magnetic field in wires fabricated with program boron powder were H{sub c2}(0) = 37 tesla, demonstrating the potential of these materials for high field magnet applications. T{sub c} in carbon-doped MgB{sub 2} powder showed a systematic decrease with increasing carbon precursor gas flows, indicating the plasma synthesis process can give precise …
Date: March 26, 2012
Creator: Marzik, James V.
System: The UNT Digital Library
ANALYSIS OF THE SALT FEED TANK CORE SAMPLE (open access)

ANALYSIS OF THE SALT FEED TANK CORE SAMPLE

The Saltstone Production Facility (SPF) immobilizes and disposes of low-level radioactive and hazardous liquid waste (salt solution) remaining from the processing of radioactive material at the Savannah River Site (SRS). Low-level waste (LLW) streams from processes at SRS are stored in Tank 50 until the LLW can be transferred to the SPF for treatment and disposal. The Salt Feed Tank (SFT) at the Saltstone Production Facility (SPF) holds approximately 6500 gallons of low level waste from Tank 50 as well as drain water returned from the Saltstone Disposal Facility (SDF) vaults. Over the past several years, Saltstone Engineering has noted the accumulation of solids in the SFT. The solids are causing issues with pump performance, agitator performance, density/level monitoring, as well as taking up volume in the tank. The tank has been sounded at the same location multiple times to determine the level of the solids. The readings have been 12, 25 and 15 inches. The SFT is 8.5 feet high and 12 feet in diameter, therefore the solids account for approximately 10 % of the tank volume. Saltstone Engineering has unsuccessfully attempted to obtain scrape samples of the solids for analysis. As a result, Savannah River National Laboratory (SRNL) …
Date: January 26, 2012
Creator: Reigel, M. & Cheng, W.
System: The UNT Digital Library
Heritable Genetic Changes in Cells Recovered From Irradiated 3D Tissue Constructs (open access)

Heritable Genetic Changes in Cells Recovered From Irradiated 3D Tissue Constructs

Combining contemporary cytogenetic methods with DNA CGH microarray technology and chromosome flow-sorting increases substantially the ability to resolve exchange breakpoints associated with interstitial deletions and translocations, allowing the consequences of radiation damage to be directly measured at low doses, while also providing valuable insights into molecular mechanisms of misrepair processes that, in turn, identify appropriate biophysical models of risk at low doses. Specific aims apply to cells recovered from 3D tissue constructs of human skin and, for the purpose of comparison, the same cells irradiated in traditional 2D cultures. The project includes research complementary to NASA/HRP space radiation project.
Date: March 26, 2012
Creator: Cornforth, Michael
System: The UNT Digital Library
Technoeconomic Evaluation of MEA versus Mixed Amines for CO2 Removal at Near-Commercial Scale at Duke Energy Gibson 3 Plant (open access)

Technoeconomic Evaluation of MEA versus Mixed Amines for CO2 Removal at Near-Commercial Scale at Duke Energy Gibson 3 Plant

None
Date: November 26, 2012
Creator: Jones, D. A.; McVey, T. F. & Friedmann, S. J.
System: The UNT Digital Library
Preparing Algebraic Multigrid for Exascale (open access)

Preparing Algebraic Multigrid for Exascale

None
Date: February 26, 2012
Creator: Baker, A H; Falgout, R D; Gahvari, H; Gamblin, T; Gropp, W; Kolev, T V et al.
System: The UNT Digital Library
SEPARATIONS AND WASTE FORMS CAMPAIGN IMPLEMENTATION PLAN (open access)

SEPARATIONS AND WASTE FORMS CAMPAIGN IMPLEMENTATION PLAN

This Separations and Waste Forms Campaign Implementation Plan provides summary level detail describing how the Campaign will achieve the objectives set-forth by the Fuel Cycle Reasearch and Development (FCRD) Program. This implementation plan will be maintained as a living document and will be updated as needed in response to changes or progress in separations and waste forms research and the FCRD Program priorities.
Date: November 26, 2012
Creator: Vienna, John D.; Todd, Terry A. & Peterson, Mary E.
System: The UNT Digital Library
Reauthorization of the Export-Import Bank: Issues and Policy Options for Congress (open access)

Reauthorization of the Export-Import Bank: Issues and Policy Options for Congress

None
Date: April 26, 2012
Creator: unknown
System: The UNT Digital Library
Requiring Parental Involvement in a Pregnant Minor’s Abortion Decision: State Laws and Recent Developments (open access)

Requiring Parental Involvement in a Pregnant Minor’s Abortion Decision: State Laws and Recent Developments

None
Date: April 26, 2012
Creator: unknown
System: The UNT Digital Library
Child Welfare: Social Security and Supplemental Security Income (SSI) Benefits for Children in Foster Care (open access)

Child Welfare: Social Security and Supplemental Security Income (SSI) Benefits for Children in Foster Care

This report begins with a discussion of the foster care system and the Social Security benefits available to eligible children, including those in foster care. It then describes the role of representative payees and their responsibilities. The report provides data on the use of Social Security benefits to reimburse states for child welfare, and includes a discussion of the Keffeler decision. Finally, the report concludes with proposals supported by some advocates to change the current practice of using SSI and other Social Security benefits to fund foster care.
Date: September 26, 2012
Creator: Moulta-Ali, Umar
System: The UNT Digital Library
Iran’s Nuclear Program: Status (open access)

Iran’s Nuclear Program: Status

None
Date: September 26, 2012
Creator: unknown
System: The UNT Digital Library
Dispute Settlement in the World Trade Organization (WTO): An Overview (open access)

Dispute Settlement in the World Trade Organization (WTO): An Overview

This report provides an overview about the Dispute Settlement in the World Trade Organization (WTO).
Date: November 26, 2012
Creator: Grimmett, Jeanne J.
System: The UNT Digital Library
Controlling Air Emissions from Outer Continental Shelf Sources: A Comparison of Two Programs—EPA and DOI (open access)

Controlling Air Emissions from Outer Continental Shelf Sources: A Comparison of Two Programs—EPA and DOI

This report contains a list of difference and its components between the Department of Interior (DOI) and the Environmental Protection Agency (EPA) in controlling air emissions from outer continental shelf sources.
Date: November 26, 2012
Creator: Ramseur, Jonathan L.
System: The UNT Digital Library
Gangs in Central America. November 2012 (open access)

Gangs in Central America. November 2012

This report describes the gang problem in Central America, discusses country and regional approaches to deal with the gangs, and analyzes U.S. policy with respect to gangs in Central America.
Date: November 26, 2012
Creator: Seelke, Clare Ribando
System: The UNT Digital Library
Entitlements and Appropriated Entitlements in the Federal Budget Process (open access)

Entitlements and Appropriated Entitlements in the Federal Budget Process

This report provides a brief explanation of spending for entitlements, including so-called appropriated entitlements, and discusses the procedural and statutory constraints on legislation affecting such entitlement spending.
Date: November 26, 2012
Creator: Heniff, Bill, Jr.
System: The UNT Digital Library
Federal Labor Relations Statutes: An Overview (open access)

Federal Labor Relations Statutes: An Overview

This report provides a brief history and overview of the aims of each of these statues. It also discusses key statutory provisions for each statute.
Date: November 26, 2012
Creator: Hegji, Alexandra
System: The UNT Digital Library
Child Welfare: A Detailed Overview of Program Eligibility and Funding for Foster Care, Adoption Assistance and Kinship Guardianship Assistance under Title IV-E of the Social Security Act (open access)

Child Welfare: A Detailed Overview of Program Eligibility and Funding for Foster Care, Adoption Assistance and Kinship Guardianship Assistance under Title IV-E of the Social Security Act

This report discusses the topic why do children enter foster care? It also discusses Title IV-E program Basics and Title IV-E Foster Care.
Date: October 26, 2012
Creator: Stoltzfus, Emilie
System: The UNT Digital Library