Resource Type

Low Frequency Fishbone Mode Induced by Circulating Particles in Spherical Tori (open access)

Low Frequency Fishbone Mode Induced by Circulating Particles in Spherical Tori

It is found that high beta in low-aspect-ratio tori tends to stabilize the fishbone instability in a plasma with energetic circulating ions. The stabilization results from enhancement of the toroidal drift motion by large Shafranov shift, which makes it difficult to reconcile the condition of considerable energy exchange between the ions and the internal kink perturbation with the condition of the resonant wave-particle interaction.
Date: February 2, 2001
Creator: Kolesnichenko, Ya. I.; Marchenko, V. S. & White, R. B.
System: The UNT Digital Library
Local Physics Basis of Confinement Degradation in JET ELMy H-Mode Plasmas and Implications for Tokamak Reactors (open access)

Local Physics Basis of Confinement Degradation in JET ELMy H-Mode Plasmas and Implications for Tokamak Reactors

First results of gyrokinetic analysis of JET [Joint European Torus] ELMy [Edge Localized Modes] H-mode [high-confinement modes] plasmas are presented. ELMy H-mode plasmas form the basis of conservative performance predictions for tokamak reactors of the size of ITER [International Thermonuclear Experimental Reactor]. Relatively high performance for long duration has been achieved and the scaling appears to be favorable. It will be necessary to sustain low Z(subscript eff) and high density for high fusion yield. This paper studies the degradation in confinement and increase in the anomalous heat transport observed in two JET plasmas: one with an intense gas puff and the other with a spontaneous transition between Type I to III ELMs at the heating power threshold. Linear gyrokinetic analysis gives the growth rate, gamma(subscript lin) of the fastest growing modes. The flow-shearing rate omega(subscript ExB) and gamma(subscript lin) are large near the top of the pedestal. Their ratio decreases approximately when the confinement degrades and the transport increases. This suggests that tokamak reactors may require intense toroidal or poloidal torque input to maintain sufficiently high |gamma(subscript ExB)|/gamma(subscript lin) near the top of the pedestal for high confinement.
Date: February 2, 2001
Creator: Budny, R. V.; Alper, B.; Borba, D.; Cordey, J. G.; Ernst, D. R. & Gowers, C.
System: The UNT Digital Library
VENUS-2 MOX Core Benchmark: Results of ORNL Calculations Using HELIOS-1.4 (open access)

VENUS-2 MOX Core Benchmark: Results of ORNL Calculations Using HELIOS-1.4

The Task Force on Reactor-Based Plutonium Disposition, now an Expert Group, was set up through the Organization for Economic Cooperation and Development/Nuclear Energy Agency to facilitate technical assessments of burning weapons-grade plutonium mixed-oxide (MOX) fuel in U.S. pressurized-water reactors and Russian VVER nuclear reactors. More than ten countries participated to advance the work of the Task Force in a major initiative, which was a blind benchmark study to compare code benchmark calculations against experimental data for the VENUS-2 MOX core at SCK-CEN in Mol, Belgium. At the Oak Ridge National Laboratory, the HELIOS-1.4 code was used to perform a comprehensive study of pin-cell and core calculations for the VENUS-2 benchmark.
Date: February 2, 2001
Creator: Ellis, RJ
System: The UNT Digital Library
Irradiation Effects for the Pulsed Fast Neutron Analysis (PFNA) Cargo Interrogation System (open access)

Irradiation Effects for the Pulsed Fast Neutron Analysis (PFNA) Cargo Interrogation System

At the request of Safety and Ecology Corporation of Tennessee, radiation effects of the proposed Pulsed Fast Neutron Analysis (PFNA) Cargo Interrogation System have been examined. First, fissile cargo were examined to determine if a significant neutron signal would be observable during interrogation. Results indicated that ample multiplication would be seen for near critical bare targets. The water-reflected sphere showed relatively little multiplication. By implication, a fissile target shielded by hydrogenous cargo might not be detectable by neutron interrogation, particularly if reliance is placed on the neutron signal. The cargo may be detectable if use can be made of the ample increase in the photon signal. Second, dose rates were calculated at various locations within and just outside the facility building. These results showed that some dose rates may be higher than the target dose rate of 0.05 mrem/h. However, with limited exposure time, the total dose may be well below the allowed total dose. Lastly, estimates were made of the activation of structures and typical cargo. Most cargo will not be exposed long enough to be activated to levels of concern. On the other hand, portions of the structure may experience buildup of some radionuclides to levels of concern.
Date: February 2, 2001
Creator: Slater, C. O.
System: The UNT Digital Library
Performance of small CST column gas generation test in radiation field (open access)

Performance of small CST column gas generation test in radiation field

The purpose of this position paper is to describe the circumstances leading to the decision to delete the dynamic CST small column radiolytic gas generation test from the current phase of tests and the impact of that decision on the Decision Phase.
Date: February 2, 2000
Creator: Jacobs, R. A.; Rueter, K. J. & Carter, J. T.
System: The UNT Digital Library
The Utilization of the Microflora Indigenous to and Present in Oil-Bearing Formations to Selectively Plug the More Porous Zones Thereby Increasing Oil Recovery During Waterflooding, Class 1 (open access)

The Utilization of the Microflora Indigenous to and Present in Oil-Bearing Formations to Selectively Plug the More Porous Zones Thereby Increasing Oil Recovery During Waterflooding, Class 1

The objectives of this project were (1) to demonstrate the in situ microbial population in a fluvial dominated deltaic reservoir could be induced to proliferate to such an extent that they will selectively restrict flow in the more porous zones in the reservoir thereby forcing injection water to flow through previously unswept areas thus improving the sweep efficiency of the waterflood and (2) to obtain scientific validation that microorganisms are indeed responsible for the increased oil recovery. One expected outcome of this new technology was the prolongation of economical life of the reservoir, i.e. economical oil recovery should continue for much longer periods in areas of the reservoir subjected to the MPPM technology than it would if it followed its historic trend.
Date: February 2, 2000
Creator: Stephens, James O.; Brown, Lewis R. & Vadie, Alex A.
System: The UNT Digital Library
Novel CO{sub 2}-thickeners for improved mobility control (open access)

Novel CO{sub 2}-thickeners for improved mobility control

The objective of this study was to design, synthesize, and characterize thickening agents for dense carbon dioxide and to evaluate their solubility and viscosity-enhancing potential in CO{sub 2}. Previously, fluoroacrylate homopolymers and fluorinated telechelic ionomers were shown to increase the viscosity of carbon dioxide by a factor of 3--4 at concentrations of 2--3 at concentrations of 4--5 wt%. This report details the findings for several new types of carbon dioxide thickening candidates. Hydrocarbon-fluorocarbon random copolymers, sulfonated hydrocarbon-fluorocarbon random copolymers, semifluorinated trialkyltin fluorides and small hydrogen-bounding compounds were evaluated.
Date: February 2, 2000
Creator: Enick, Dr. Robert M.; Beckman, Dr. Eric J. & Hamilton, Dr. Andrew
System: The UNT Digital Library
Computed Tomography (CT) Standards (open access)

Computed Tomography (CT) Standards

There is currently no standardized method to check the measurement capabilities of computed tomography (CT) systems within industry. The current method to determine the functionality of CT systems is by use of a test phantom to represent the actual part to be tested. A standard method to check the software algorithms when measuring such parameters as density of a material and the size of an object is not readily available. Many different materials are evaluated by CT systems. A set of standards necessitates the inclusion of materials that cover the gambit of materials encountered. The Federal Manufacturing and Technologies (FM and T) CT standards are designed to accommodate a variety of materials and several different sizes. This provides a method to check the CT system for size measurement capabilities and material density measurement as well as aid in optimizing the geometric parameters of the machine configuration.
Date: February 2, 2000
Creator: Hubert, R. R. & Beach, J. M.
System: The UNT Digital Library
Practical superconductor development for electrical power applications: Quarterly report for the period ending December 31, 1999 (open access)

Practical superconductor development for electrical power applications: Quarterly report for the period ending December 31, 1999

This is a multiyear experimental research program focused on improving relevant material properties of high-T{sub c} superconductors (HTSS) and on development of fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of the Argonne (ANL) program. Recent results on substrate deposition for coated conductors, vortex studies, development of hardened Ag-alloy sheaths for powder-in-tube conductors, and sol-gel processing of NdBa{sub 2}Cu{sub 3}O{sub x} (Nd-123) are presented.
Date: February 2, 2000
Creator: unknown
System: The UNT Digital Library
Novel CO{sub 2}-thickeners for improved mobility control (open access)

Novel CO{sub 2}-thickeners for improved mobility control

The objective of this study was to incorporate carbon dioxide-philic functionalities into the structure of a telechelic ionomers in an attempt to design a carbon dioxide-thickener. Alkyl analogs of these end-functionalized polymers have been successfully employed in dilute concentration to increase the viscosity of organic liquids or to induce gelation. The ionic end-groups associated in solution, establishing a viscosity enhancing macromolecular structure. More dramatic viscosity changes have been attained at very dilute concentrations with low MW associating compounds than with ultra-high MW polymers. The apparent molecular weight of the associative network greatly exceeds the MW of the covalently-bounded polymer in solution, yet the relatively low molecular weight of the compound favors its solubilization.
Date: February 2, 2000
Creator: Enick, Dr. Robert M.; Beckman, Dr. Eric J. & Hamilton, Dr. Andrew
System: The UNT Digital Library
Novel CO{sub 2}-thickeners for improved mobility control (open access)

Novel CO{sub 2}-thickeners for improved mobility control

The objective of this study was to design, synthesize, and characterize thickening agents for dense carbon dioxide and to evaluate their solubility and viscosity-enhancing potential in CO{sub 2}. Previously, hydrocarbon-fluorocarbon random copolymers, sulfated hydrocarbon-fluorocarbon random copolymers, semifluorinated trialkyltin fluorides and small hydrogen-bonding compounds were evaluated. Random copolymers of styrene and heptadecafluorodecyl acrylate yielded substantial increases in viscosity. The amount of styrene varied between 22--40 mole% in the copolymer. Falling cylinder viscometry results indicated that the 29% styrene--71% fluoroacrylate copolymer induced (at 295K and 34.5 Mpa) increases of 10, 60 and 250 at copolymer concentrations of 1, 3 and 5wt%, respectively.
Date: February 2, 2000
Creator: Enick, Dr. Robert M.; Beckman, Dr. Eric J. & Hamilton, Dr. Andrew
System: The UNT Digital Library
Precision Cleaning Titanium Components (open access)

Precision Cleaning Titanium Components

Clean bond surfaces are critical to the operation of diffusion bonded titanium engine components. These components can be contaminated with machining coolant, shop dirt, and fingerprints during normal processing and handling. These contaminants must be removed to achieve acceptable bond quality. As environmental concerns become more important in manufacturing, elimination of the use of hazardous materials is desired. For this reason, another process (not using nitric-hydrofluoric acid solution) to clean titanium parts before bonding was sought. Initial cleaning trials were conducted at Honeywell to screen potential cleaning techniques and chemistries. During the initial cleaning process screening phase, Pratt and Whitney provided Honeywell with machined 3 inch x 3 inch x 1 inch titanium test blocks. These test blocks were machined with a water-based machining coolant and exposed to a normal shop environment and handling. (Honeywell sectioned one of these blocks into smaller samples to be used for additional cleanliness verification analyses.) The sample test blocks were ultrasonically cleaned in alkaline solutions and AUGER analysis was used by Honeywell FM and T to validate their cleanliness. This information enabled selection of final cleaning techniques and solutions to be used for the bonding trials. To validate Honeywell's AUGER data and to verify …
Date: February 2, 2000
Creator: Hand, T.E. & Bohnert, G.W.
System: The UNT Digital Library
The Autocatalytic Behavior of Trimethylindium During Thermal Decomposition (open access)

The Autocatalytic Behavior of Trimethylindium During Thermal Decomposition

Pyrolysis of trimethylindium (TMIn) in a hot-wall flow-tube reactor has been investigated at temperatures between 573 and 723 K using a modulated molecular-beam mass-sampling technique and detailed numerical modeling. The TMIn was exposed to various mixtures of carrier gases: He, H{sub 2}, D{sub 2}, and C{sub 2}H{sub 4}, in an effort to elucidate the behavior exhibited by this compound in different chemical environments. The decomposition of TMIn is a heterogeneous, autocatalytic process with an induction period that is carrier-gas dependent and lasts on the order of minutes. After activation of the tube wall, the thermolysis exhibits a steady-state behavior that is surface mediated. This result is contrary to prior literature reports, which state that decomposition occurs in the gas phase via successive loss of the CH{sub 3} ligands. This finding also suggests that the bond dissociation energy for the (CH{sub 3}){sub 2}In-CH{sub 3} bond derived from flow-tube investigations is erroneous and should be reevaluated.
Date: February 2, 2000
Creator: McDaniel, Anthony H. & Allendorf, M. D.
System: The UNT Digital Library
Novel CO{sub 2}-thickeners for improved mobility control (open access)

Novel CO{sub 2}-thickeners for improved mobility control

The objective of this study was to design, synthesize, and characterize thickening agents for dense carbon dioxide and to evaluate their solubility and viscosity-enhancing potential in CO{sub 2}. Hydrocarbon-fluorocarbon random copolymers, sulfated hydrocarbon-fluorocarbon random copolymers, semifluorinated trialkyltin fluorides and small hydrogen-bonding compounds were evaluated. Random copolymers of styrene and heptadecafluorodecyl acrylate were characterized by high solubility ion dense carbon dioxide and the most substantial increases in solution viscosity. Falling cylinder viscometry results indicated that the 29%styrene--71%fluoroacylate bulk-polymerized copolymer induced 2--250 fold increases in viscosity at copolymer concentrations of 0.2--5.0wt%.
Date: February 2, 2000
Creator: Enick, Robert M.; Beckman, Eric J. & Hamilton, Andrew
System: The UNT Digital Library
Novel CO{sub 2}-thickeners for improved mobility control (open access)

Novel CO{sub 2}-thickeners for improved mobility control

The objective of this study was to design, synthesize, and characterize thickening agents for dense carbon dioxide and to evaluate their solubility and viscosity-enhancing potential in CO{sub 2}. Hydrocarbon-fluorocarbon random copolymers, sulfonated hydrocarbon-fluorocarbon random copolymers, semifluorinated trialkyltin fluorides and small hydrogen-bonding compounds have been evaluated. Random copolymers of styrene and heptadecafluorodecyl acrylate yielded substantial increases in viscosity. Falling cylinder viscometry results indicated that the 29%styrene--71%fluoroacrylate bulk-polymerized copolymer induced very significant viscosity increases at copolymer concentrations of 0.1--5.0wt%.
Date: February 2, 2000
Creator: Enick, Dr. Robert M.; Beckman, Dr. Eric J. & Hamilton, Dr. Andrew
System: The UNT Digital Library
The Iran Sanctions Act (ISA) (open access)

The Iran Sanctions Act (ISA)

This report discusses the increasing international pressure on Iran to curb its nuclear program and how that pressure discourages foreign firms from investing in Iran's energy sector, hindering Iran's efforts to expand oil production. It also discusses the history and progress of the formal U.S. effort to curb energy investment in Iran, which began with the Iran Sanctions Act (ISA) in 1996
Date: February 2, 2009
Creator: Katzman, Kenneth
System: The UNT Digital Library
Family Law: Congress's Authority to Legislate on Domestic Relations Questions (open access)

Family Law: Congress's Authority to Legislate on Domestic Relations Questions

This report discusses the extent to which Congress is constitutionally authorized to legislate on family law questions, and includes examples of present laws utilizing the various approaches available in this area.
Date: February 2, 2009
Creator: Smith, Alison M.
System: The UNT Digital Library
War Powers Resolution: Presidential Compliance (open access)

War Powers Resolution: Presidential Compliance

This report gives a summary of the usage of the War Powers Resolution (WPR) and various issues related to proposals to modify or repeal the resolution. The report summarizes most recent developments and background, and gives an overview of United Nations actions, and WPR activities in former Yugoslavia/Bosnia, Kosovo, Iraq (post-1991), Haiti, and Somalia. It also includes commentary on the instances formally reported under the WPR, consultation with Congress, and the current issues which Congress is considering.
Date: February 2, 2009
Creator: Grimmett, Richard F.
System: The UNT Digital Library
Proposed Funding for Workforce Development in the American Recovery and Reinvestment Act (ARRA) of 2009 (open access)

Proposed Funding for Workforce Development in the American Recovery and Reinvestment Act (ARRA) of 2009

This report provides a brief overview of the key provisions related to workforce development programs administered by the U.S. Department of Labor (DOL) that were included in the House and Senate versions of the American Recovery and Reinvestment Act of 2009 (ARRA). It also provides estimates of state grants for programs for which these estimates are relevant and for which data needed to produce the estimates are available. The estimates are shown in appendix tables that present state-by-state allocations for adult, youth, and dislocated worker programs.
Date: February 2, 2009
Creator: Bradley, David H. & Lordeman, Ann
System: The UNT Digital Library
Homeland Security: Management of First Responder Grant Programs Has Improved, but Challenges Remain (open access)

Homeland Security: Management of First Responder Grant Programs Has Improved, but Challenges Remain

A letter report issued by the Government Accountability Office with an abstract that begins "The Office for Domestic Preparedness (ODP)--originally established in 1998 within the Department of Justice to help state and local first responders acquire specialized training and equipment needed to respond to terrorist incidents--was transferred to the Department of Homeland Security upon its creation in March 2003. After September 11, 2001, the scope and size of ODP's grant programs expanded. For example, from fiscal year 2001 through fiscal year 2003, ODP grants awarded to states and some urban areas grew from about $91 million to about $2.7 billion. This growth raised questions about the ability of ODP and states to ensure that the domestic preparedness grant programs--including statewide and urban area grants--are managed effectively and efficiently. GAO addressed (1) how statewide and urban area grants were administered in fiscal years 2002 and 2003 so that ODP could ensure that grant funds were spent in accordance with grant guidance and state preparedness planning and (2) what time frames Congress and ODP established for awarding and distributing grants, and how time frames affected the grant cycle."
Date: February 2, 2005
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
International Taxation: Information on Federal Contractors With Offshore Subsidiaries (open access)

International Taxation: Information on Federal Contractors With Offshore Subsidiaries

A letter report issued by the General Accounting Office with an abstract that begins "Every year, U.S.-based multinational corporations transfer hundreds of billions of dollars of goods and services between their affiliates in the United States and their foreign subsidiaries. Such transactions may be a part of normal business operations for corporations with foreign subsidiaries. However, it is generally recognized that given the variation in corporate tax rates across countries, an incentive exists for corporations with foreign subsidiaries to reduce their overall tax burden by maximizing the income they report in countries with low income tax rates, and minimizing the income they report in or repatriate to countries with high income tax rates. Various studies have suggested that U.S.-based multinational corporations appear to engage in transactions such as these that shift income from their affiliates in high-tax countries to subsidiaries in low-tax countries to take advantage of the differences in tax rates in foreign countries. In 2002, GAO reported that 4 of the 100 largest publicly traded federal contractors are incorporated in a "tax haven" country that either does not tax corporate income or taxes the income at a low rate. As a follow-up to the report, Congress asked us …
Date: February 2, 2004
Creator: United States. General Accounting Office.
System: The UNT Digital Library
National Nuclear Security Administration: Contractors' Strategies to Recruit and Retain a Critically Skilled Workforce Are Generally Effective (open access)

National Nuclear Security Administration: Contractors' Strategies to Recruit and Retain a Critically Skilled Workforce Are Generally Effective

A letter report issued by the Government Accountability Office with an abstract that begins "Responsibility for ensuring the safety and reliability of the nuclear weapons stockpile rests upon a cadre of workers at eight contractor-operated National Nuclear Security Administration (NNSA) weapons facilities. Many of these workers--including scientists, engineers, and technicians--have "critical" skills needed to maintain the stockpile. About 37 percent of these workers are at or near retirement age, raising concern about whether these specialists will have time to pass on their knowledge and expertise to new recruits. In this context, Congress asked us to (1) describe the approaches that NNSA, its contractors, and organizations with similar workforces are using to recruit and retain critically skilled workers; (2) assess the extent to which these approaches have been effective; and (3) describe any remaining challenges, strategies to mitigate these challenges, and the similarity of these challenges and strategies to those of organizations with comparable workforces."
Date: February 2, 2005
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
Clean Air Act: Key Stakeholders' Views on Revisions to the New Source Review Program (open access)

Clean Air Act: Key Stakeholders' Views on Revisions to the New Source Review Program

A letter report issued by the General Accounting Office with an abstract that begins "Environmental Protection Agency (EPA) revisions to the New Source Review (NSR) program to control industrial emissions have drawn attention from state and local agencies that implement the program, as well as industry and environmental and health groups. Under the revisions, companies may not have to install pollution controls when making some facility changes. GAO was asked to obtain the opinions of state air quality officials and other stakeholders on the impact of both the final and proposed revisions EPA issued in December 2002. GAO obtained survey responses from NSR program managers in 44 states and certain localities and contacted six environmental and health groups, and eight industry groups active in the NSR debate. Survey details are available in GAO-04-337SP."
Date: February 2, 2004
Creator: United States. General Accounting Office.
System: The UNT Digital Library
State Department: State Has Initiated a More Systematic Approach for Managing Its Aviation Fleet (open access)

State Department: State Has Initiated a More Systematic Approach for Managing Its Aviation Fleet

A letter report issued by the Government Accountability Office with an abstract that begins "The Department of State's (State) Bureau of International Narcotics and Law Enforcement Affairs (INL) owns 357 helicopters and fixed-wing aircraft (valued at over $340 million) primarily to help carry out its counternarcotics efforts, such as aerial eradication of drug crops in Colombia. INL relies on contractor support to help maintain and operate its aircraft. In 2004, GAO analysis showed that INL lagged behind other agencies in implementing Office of Management and Budget (OMB) and General Services Administration (GSA) aviation fleet management principles. GAO was mandated to review INL's management and oversight of this fleet. GAO specifically examined (1) the extent INL has complied with OMB and GSA aviation fleet management guidance and (2) how INL has overseen its aviation support contracts. Since INL has undertaken initiatives to address the weaknesses GAO observed, GAO makes no recommendations. GAO will follow up to ensure that these initiatives are completed, as planned. In comments on this report, State highlighted reforms under way. State also indicated that INL conducted analyses to justify most aviation investments. GAO notes, however, that the documentation provided did not reflect the key analyses called for …
Date: February 2, 2007
Creator: United States. Government Accountability Office.
System: The UNT Digital Library