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Ultimate strength of carbon nanotubes: A theoretical study (open access)

Ultimate strength of carbon nanotubes: A theoretical study

Article on a theoretical study of the ultimate strength of carbon nanotubes.
Date: March 27, 2002
Creator: Zhao, Qingzhong; Buongiorno Nardelli, Marco & Bernholc, Jerry
System: The UNT Digital Library
New Pulsed Power Technology for High Current Accelerators (open access)

New Pulsed Power Technology for High Current Accelerators

Recent advances in solid-state modulators now permit the design of a new class of high current accelerators. These new accelerators will be able to operate in burst mode at frequencies of several MHz with unprecedented flexibility and precision in pulse format. These new modulators can drive accelerators to high average powers that far exceed those of any other technology and can be used to enable precision beam manipulations. New insulator technology combined with novel pulse forming lines and switching may enable the construction of a new type of high gradient, high current accelerator. Recent developments in these areas will be reviewed.
Date: June 27, 2002
Creator: Caporaso, G J
System: The UNT Digital Library
The Godunov-Inverse Iteration: A Fast and Accurate Solution to the Symmetric Tridiagonal Eigenvalue Problem. (open access)

The Godunov-Inverse Iteration: A Fast and Accurate Solution to the Symmetric Tridiagonal Eigenvalue Problem.

We present a new hybrid algorithm based on Godunov's method for computing eigenvectors of symmetric tridiagonal matrices and Inverse Iteration, which we call the Godunov-Inverse Iteration Algorithm. We use eigenvectors computed according to Godunov's method as starting vectors in the Inverse Iteration, replacing any nonnumeric elements of the Godunov eigenvectors with random uniform numbers. We use the right-hand bounds of the Ritz intervals found by the bisection method as Inverse Iteration shifts, while staying within guaranteed error bounds. In most test cases convergence is reached after only one step of the iteration, producing error estimates that are as good as or superior to those produced by standard Inverse Iteration implementations.
Date: November 27, 2002
Creator: Matsekh, Anna M.
System: The UNT Digital Library
Molecular Foundry Workshop draws overflow crowd to BerkeleyLab (open access)

Molecular Foundry Workshop draws overflow crowd to BerkeleyLab

Nanoscale science and technology is now one of the top research priorities in the United States. With this background, it is no surprise that an overflow crowd or more than 350 registrants filled two auditoriums to hear about and contribute ideas for the new Molecular Foundry during a two-day workshop at the Lawrence Berkeley National Laboratory (Berkeley Lab). Scheduled to open for business at Berkeley Labin early 2006, the Molecular Foundry is one of three Nanoscale Science Research Centers (NSRCs) put forward for funding by the DOE's Office of Basic Energy Sciences (BES).
Date: November 27, 2002
Creator: Robinson, Art
System: The UNT Digital Library
Beta4 integrin-dependent formation of polarized three-dimensionalarchitecture confers resistance to apoptosis in normal and malignantmammary epithelium (open access)

Beta4 integrin-dependent formation of polarized three-dimensionalarchitecture confers resistance to apoptosis in normal and malignantmammary epithelium

Tumor cells can evade chemotherapy by acquiring resistanceto apoptosis. We investigated the molecular mechanism whereby malignantand nonmalignant mammary epithelial cells become insensitive toapoptosis. We show that regardless of growth status formation ofpolarized, three-dimensional structures driven by basement membraneconfers protection to apoptosis in both nonmalignant and malignantmammary epithelial cells. By contrast, irrespective of their malignantstatus, nonpolarized structures are sensitive to induction of apoptosis.Resistance to apoptosis requires ligation of beta4 integrins, whichregulates tissue polarity, hemidesmosome formation and NFkB activation.Expression of beta4 integrin that lacks the hemidesmosome targetingdomain interferes with tissue polarity and NFkB activation and permitsapoptosis. These results indicate that integrin-induced polarity maydrive tumor cell resistance to apoptosis-inducing agents via effects onNFkB.
Date: August 27, 2002
Creator: Weaver, Valerie M.; Lelievre, Sophie; Lakins, Johnathon N.; Chrenek, Micah A.; Jones, Jonathan C.R.; Giancotti, Filippo et al.
System: The UNT Digital Library
Fission barrier properties, resonance fluctuations and isomer fission cross-sections. (open access)

Fission barrier properties, resonance fluctuations and isomer fission cross-sections.

Although the main picture of fission bamer physics was established some time ago many of the details still have to be settled. Consequently, the application to evaluation of crosssections of unmeasurable or exotic nuclides and their excited states is still in its early stages. In this paper I consider some of these details and explore the possibility of quantitative estimation of fission cross-sections
Date: November 27, 2002
Creator: Lynn, J. E. (J. Eric) & Hayes, A. C. (Anna C.)
System: The UNT Digital Library
The USNRC's Final Regulations for Disposal of High-Level Radioactive Wastes in a Potential Geologic Repository at Yucca Mountain (open access)

The USNRC's Final Regulations for Disposal of High-Level Radioactive Wastes in a Potential Geologic Repository at Yucca Mountain

On February 22, 1999, the U.S. Nuclear Regulatory Commission (NRC) proposed licensing criteria in a new, separate part of its regulations, at 10 CFR Part 63 (hereafter referred to as Part 63), for disposal of high-level radioactive waste (HLW) in a potential geologic repository at Yucca Mountain, Nevada (1). After publication of the proposed Part 63, the staff provided members of the public and other stakeholders multiple opportunities to discuss the proposed requirements. On June 13, 2001, the U.S. Environmental Protection Agency (EPA) issued final environmental standards for a potential geologic repository at Yucca Mountain, Nevada at 40 CFR Part 197 (2), as mandated by the Energy Policy Act of 1992 (EnPA)(3). The NRC has prepared its final regulations based on careful review and consideration of the public comments received on its proposed rule and the statutory direction for NRC to adopt technical criteria consistent with final EPA standards.
Date: February 27, 2002
Creator: McCartin, T.; Kotra, J.; Pohle, J. & Wittmeyer, G.
System: The UNT Digital Library
Integrated Management of all Historical, Operational and Future Decomissioning Solid ILW at Dounreay (open access)

Integrated Management of all Historical, Operational and Future Decomissioning Solid ILW at Dounreay

This paper describes major components of the Dounreay Site Restoration Plan, DSRP to deal with the site's solid intermediate level waste, ILW legacy. Historic solid ILW exists in the Shaft (disposals between 1959 and 1977), the Wet Silo (operated between 1973 and 1998), and in operating engineered drummed storage. Significant further arisings are expected from future operations, post-operations clean out and decommissioning through to the completion of site restoration, expected to be complete by about 2060. The raw waste is in many solid forms and also incorporates sludge, some fissile material and hazardous chemical components. The aim of the Solid ILW Project is to treat and condition all this waste to make it passively safe and in a form which can be stored for a substantial period, and then transported to the planned U.K. national deep repository for ILW disposal. The Solid ILW Project involves the construction of head works for waste retrieval operations at the Shaft and Wet Silo, a Waste Treatment Plant and a Conditioned Waste Store to hold the conditioned waste until the disposal facilities become available. In addition, there are infrastructure activities to enable the new construction: contaminated ground remediation, existing building demolition, underground and overground …
Date: February 27, 2002
Creator: Graham, D.
System: The UNT Digital Library
Progress Towards International Repositories (open access)

Progress Towards International Repositories

The nuclear fuel cycle is designed to be very international, with some specialist activities (e.g. fuel fabrication, reprocessing, etc.) being confined to a few countries. Nevertheless, political and public opposition has in the past been faced by proposals to internationalise the back-end of the cycle, in particular waste disposal. Attitudes, however, have been changing recently and there is now more acceptance of the general concept of shared repositories and of specific proposals such as that of Pangea. However, as for national facilities, progress towards implementation of shared repositories will be gradual. Moreover, the best vehicle for promoting the concept may not be a commercial type of organization. Consequently the Pangea project team are currently establishing a widely based Association for this purpose.
Date: February 27, 2002
Creator: McCombie, C. & Chapman, N.
System: The UNT Digital Library
Presentation of the ERFB Bitumenized Waste Drum Retrieval Facility (open access)

Presentation of the ERFB Bitumenized Waste Drum Retrieval Facility

The bitumenized waste drum facility (ERFB) is built on the Marcoule site and is intended to handle the historic bitumenized waste of the site, that were conditioned in metallic drums. The purpose of the facility is to retrieve the drums stored in pits, condition them in stainless steel overpacks and produce packages ready to be shipped to the multipurpose interim storage (EIP) facility. The ERBF includes a mobile frame structure capable to shift from one pit to another. It is used to recover drums and characterizes them (weight, radiological properties, etc.) and to repack them according to their state. The first operation results are provided.
Date: February 27, 2002
Creator: Cauquil, G.; Mistral, J. P.; Themines, R.; Fulleringer, D. & Hauss, S.
System: The UNT Digital Library
Recent Developments in Nuclear Waste Management in Canada (open access)

Recent Developments in Nuclear Waste Management in Canada

This paper describes recent developments in the field of nuclear waste management in Canada with a focus on management of nuclear fuel waste. Of particular significance is the April 2001 tabling in the Canadian House of Commons of Bill C-27, An Act respecting the long-term management of nuclear fuel waste. At the time of finalizing this paper (January 15, 2002), Bill C-27 is in Third Reading in the House of Commons and is expected to move to the Senate in February. The Nuclear Fuel Waste Act is expected to come into force later in 2002. This Act requires the three nuclear utilities in Canada owning nuclear fuel waste to form a waste management organization and deposit funds into a segregated fund for nuclear fuel waste long-term management. The waste management organization is then required to perform a study of long-term management approaches for nuclear fuel waste and submit the study to the federal government within three years. The federal government will select an approach for implementation by the waste management organization. The paper discusses the activities that the nuclear fuel waste owners currently have underway to prepare for the formation of the waste management organization. As background, the paper reviews …
Date: February 27, 2002
Creator: King, F.
System: The UNT Digital Library
Subsurface Contaminants Focus Area (SCFA) Lead Laboratory Providing Technical Assistance to the DOE Weapons Complex in Subsurface Contamination (open access)

Subsurface Contaminants Focus Area (SCFA) Lead Laboratory Providing Technical Assistance to the DOE Weapons Complex in Subsurface Contamination

The Subsurface Contaminants Focus Area (SCFA), a DOE-HQ EM-50 organization, is hosted and managed at the Savannah River Site in Aiken, South Carolina. SCFA is an integrated program chartered to find technology and scientific solutions to address DOE subsurface environmental restoration problems throughout the DOE Weapons Complex. Since its inception in 1989, the SCFA program has resulted in a total of 269 deployments of 83 innovative technologies. Until recently, the primary thrust of the program has been to develop, demonstrate, and deploy those remediation technology alternatives that are solutions to technology needs identified by the DOE Sites. Over the last several years, the DOE Sites began to express a need not only for innovative technologies, but also for technical assistance. In response to this need, DOE-HQ EM-50, in collaboration with and in support of a Strategic Lab Council recommendation directed each of its Focus Areas to implement a Lead Laboratory Concept to enhance their technical capabilities. Because each Focus Area is unique as defined by the contrast in either the type of contaminants involved or the environments in which they are found, the Focus Areas were given latitude in how they set up and implemented the Lead Lab Concept. The …
Date: February 27, 2002
Creator: Wright, J. A. Jr. & Corey, J. C.
System: The UNT Digital Library
Development of a Fuel Containing Material Removal and Waste Management Strategy for the Chernobyl Unit 4 Shelter (open access)

Development of a Fuel Containing Material Removal and Waste Management Strategy for the Chernobyl Unit 4 Shelter

A study was performed to develop a strategy for the removal of fuel-containing material (FCM) from the Chernobyl Unit 4 Shelter and for the related waste management. This study was performed during Phase 1 of the Shelter Implementation Plan (SIP) and was funded by the Chernobyl Shelter Fund. The main objective for Phase 2 of the SIP is to stabilize the Shelter and to construct a New Confinement (NC) by the year 2007. In addition, the SIP includes studies on the strategy and on the conceptual design implications of the removal of FCM from the Shelter. This is considered essential for the ultimate goal, the transformation of the Shelter into an environmentally safe system.
Date: February 27, 2002
Creator: Tokarevsky, V. V.; Shibetsky, Y. A.; Leister, P.; Davison, W. R.; Follin, J. F.; McNair, J. et al.
System: The UNT Digital Library
Mixed Waste Treatment Cost Analysis for a Range of GeoMelt Vitrification Process Configurations (open access)

Mixed Waste Treatment Cost Analysis for a Range of GeoMelt Vitrification Process Configurations

GeoMelt is a batch vitrification process used for contaminated site remediation and waste treatment. GeoMelt can be applied in several different configurations ranging from deep subsurface in situ treatment to aboveground batch plants. The process has been successfully used to treat a wide range of contaminated wastes and debris including: mixed low-level radioactive wastes; mixed transuranic wastes; polychlorinated biphenyls; pesticides; dioxins; and a range of heavy metals. Hypothetical cost estimates for the treatment of mixed low-level radioactive waste were prepared for the GeoMelt subsurface planar and in-container vitrification methods. The subsurface planar method involves in situ treatment and the in-container vitrification method involves treatment in an aboveground batch plant. The projected costs for the subsurface planar method range from $355-$461 per ton. These costs equate to 18-20 cents per pound. The projected cost for the in-container method is $1585 per ton. This cost equates to 80 cents per pound. These treatment costs are ten or more times lower than the treatment costs for alternative mixed waste treatment technologies according to a 1996 study by the US Department of Energy.
Date: February 27, 2002
Creator: Thompson, L. E.
System: The UNT Digital Library
United States Department of Energy Nuclear Materials Stewardship (open access)

United States Department of Energy Nuclear Materials Stewardship

The Department of Energy launched the Nuclear Materials Stewardship Initiative in January 2000 to accelerate the work of achieving integration and cutting long-term costs associated with the management of the Department's nuclear materials, with the principal focus on excess materials. Management of nuclear materials is a fundamental and enduring responsibility that is essential to meeting the Department's national security, nonproliferation, energy, science, and environmental missions into the distant future. The effective management of nuclear materials is important for a set of reasons: (1) some materials are vital to our national defense; (2) the materials pose physical and security risks; (3) managing them is costly; and (4) costs are likely to extend well into the future. The Department currently manages nuclear materials under eight programs, with offices in 36 different locations. Through the Nuclear Materials Stewardship Initiative, progress was during calendar year 20 00 in achieving better coordination and integration of nuclear materials management responsibilities and in evaluating opportunities to further coordinate and integrate cross-program responsibilities for the treatment, storage, and disposition of excess nuclear materials. During CY 2001 the Departmental approach to nuclear materials stewardship changed consistent with the business processes followed by the new administration. This paper reports on …
Date: February 27, 2002
Creator: Newton, J. W.
System: The UNT Digital Library
High Level Waste Tank Closure Project at the Idaho National Engineering and Environmental Laboratory (open access)

High Level Waste Tank Closure Project at the Idaho National Engineering and Environmental Laboratory

The Department of Energy, Idaho Operations Office (DOE-ID) is making preparations to close two underground high-level waste (HLW) storage tanks at the Idaho National Engineering and Environmental Laboratory (INEEL) to meet Resource Conservation and Recovery Act (RCRA) regulations and Department of Energy orders. Closure of these two tanks is scheduled for 2004 as the first phase in closure of the eleven 300,000 gallon tanks currently in service at the Idaho Nuclear Technology and Engineering Center (INTEC). The INTEC Tank Farm Facility (TFF) Closure sequence consists of multiple steps to be accomplished through the existing tank riser access points. Currently, the tank risers contain steam and process waste lines associated with the steam jets, corrosion coupons, and liquid level indicators. As necessary, this equipment will be removed from the risers to allow adequate space for closure equipment and activities.
Date: February 27, 2002
Creator: Wessman, D. L. & Quigley, K. D.
System: The UNT Digital Library
More modular invariant anomalous U(1) breaking (open access)

More modular invariant anomalous U(1) breaking

We consider the case of several scalar fields, charged under a number of U(1) factors, acquiring vacuum expectation values due to anomalous U(1). We demonstrate how to make redefinitions at the superfield level in order to account for tree-level exchange of vector supermultiplets in the effective supergravity theory of the light fields in the supersymmetric vacuum phase. Our approach builds up on previous results that we obtained in a more elementary case. We find that the modular weights of light fields are typically shifted from their original values, allowing an interpretation in terms of the preservation of modular invariance in the effective theory. We address various subtleties in defining unitary gauge that are associated with the noncanonical Kahler potential of modular invariant supergravity, the vacuum degeneracy, and the role of the dilaton field. We discuss the effective superpotential for the light fields and note how proton decay operators may be obtained when the heavy fields are integrated out of the theory at the tree-level. We also address how our formalism may be extended to describe the generalized Green-Schwarz mechanism for multiple anomalous U(1)'s that occur in four-dimensional Type I and Type IIB string constructions.
Date: June 27, 2002
Creator: Gaillard, Mary K. & Giedt, Joel
System: The UNT Digital Library
The Decommissioning of the Trino Nuclear Power Plant (open access)

The Decommissioning of the Trino Nuclear Power Plant

Following a referendum in Italy in 1987, the four Nuclear Power Plants (NPPs) owned and operated by the state utility ENEL were closed. After closing the NPPs, ENEL selected a ''safestore'' decommissioning strategy; anticipating a safestore period of some 40-50 years. This approach was consistent with the funds collected during plant operation, and was reinforced by the lack of both a waste repository and a set of national free release limits for contaminated materials in Italy. During 1999, twin decisions were made to privatize ENEL and to transform the nuclear division into a separate subsidiary of the ENEL group. This group was renamed Sogin and during the following year, ownership of the company was transferred to the Italian Treasury. On formation, Sogin was asked by the Italian government to review the national decommissioning strategy. The objective of the review was to move from a safestore strategy to a prompt decommissioning strategy, with the target of releasing all of the nuclear sites by 2020. It was recognized that this target was conditional upon the availability of a national LLW repository together with interim stores for both spent fuel and HLW by 2009. The government also agreed that additional costs caused by …
Date: February 27, 2002
Creator: Brusa, L.; DeSantis, R.; Nurden, P. L.; Walkden, P. & Watson, B.
System: The UNT Digital Library
Current Status of the United Kingdom Programme for Long-Term Radioactive Waste Management (open access)

Current Status of the United Kingdom Programme for Long-Term Radioactive Waste Management

In 1997, the UK programme for the deep disposal of radioactive waste was ''stopped dead in its tracks'' with the refusal by the Secretary of State for the Environment to allow Nirex to go ahead with its plans for an underground Rock Characterisation Facility at Sellafield in north-west England. Since that time a House of Lords' Select Committee has held an inquiry into what went wrong and what the way ahead should be. In addition, Nirex and the nuclear industry players have also been analyzing the past with a view to learning from the experience in taking things forward. In Nirex's view this is essentially an ethical issue; the waste exists and we should deal with it in this generation. Three areas need to be better addressed if a successful program of management of the nation's radioactive waste is to be achieved: the process of how policy development and implementation can be achieved; the structure of the nuclear industry and its relationship to the waste management organization; and the behavior of the players in their interaction with stakeholders. All three are underpinned by the need for transparency. In recognition that developing a policy for managing radioactive waste has to be …
Date: February 27, 2002
Creator: Murray, C. H.; Hooper, A. J. & Mathieson, J.
System: The UNT Digital Library
In-Situ Grouting Treatability Study for the Idaho National Engineering and Environmental Laboratory Subsurface Disposal Area-Transuranic Pits and Trenches (open access)

In-Situ Grouting Treatability Study for the Idaho National Engineering and Environmental Laboratory Subsurface Disposal Area-Transuranic Pits and Trenches

At the Idaho National Engineering and Environmental Laboratory (INEEL), a Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) treatability study is being performed to examine the technology of in situ grouting for final in situ disposal of buried mixed transuranic (TRU) waste. At the INEEL, there is over 56,000 cubic meters of waste commingled with a similar amount of soil in a shallow (3-5 m) land burial referred to as Waste Area Group 7-13/14. Since this buried waste has been declared on the National Priorities List under CERCLA, it is being managed as a superfund site. Under CERCLA, options for this waste include capping and continued monitoring, retrieval and ex situ management of the retrieved waste, in situ stabilization by vitrification or grouting, in situ thermal dissorption, or some combination of these options. In situ grouting involves injecting grout at high pressures (400 bars) directly into the waste to create a solid monolith. The in situ grouting process is expected to both stabilize the waste against subsidence and provide containment against migration of waste to the Snake River Plain Aquifer lying 150-200 m below the waste. The treatability study involves bench testing, implementability testing, and field testing. The bench testing …
Date: February 27, 2002
Creator: Loomis, G. G.; Jessmore, J. J.; Sehn, A. L. & Miller, C. M.
System: The UNT Digital Library
U.S. Department of Energy's Siting Guidelines at 10 CFR 963 (open access)

U.S. Department of Energy's Siting Guidelines at 10 CFR 963

The U.S. Department of Energy (DOE) has amended the policies under the Nuclear Waste Policy Act of 1982 for evaluating the suitability of Yucca Mountain, Nevada, as a site for development of a nuclear waste repository. The final rule at Title 10, Part 963 of the Code of Federal Regulations (10 CFR Part 963) focuses on the criteria and methodology to be used for evaluating relevant geological and other related aspects of the Yucca Mountain site. Consistent with the long standing policy to conform the DOE suitability guidelines for its nuclear waste repository program to licensing regulations of the U.S. Nuclear Regulatory Commission (NRC), the DOE's criteria and methodology are consistent with the NRC's recently final regulations for licensing a nuclear waste repository at Yucca Mountain.
Date: February 27, 2002
Creator: Kouts, C. A.; Murray, R. C.; Voegele, M. D. & Boyle, W. L.
System: The UNT Digital Library
Tube-wave suppression in single-well seismic acquisition (open access)

Tube-wave suppression in single-well seismic acquisition

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Date: February 27, 2002
Creator: Daley, Thomas M.; Gritto, Roland; Majer, Ernest L. & West, Phillip
System: The UNT Digital Library
Rancho Seco-Planning for Large Components (open access)

Rancho Seco-Planning for Large Components

The Rancho Seco Nuclear Generating Station ceased operation in June of 1989 and entered an extended period of Safestor to allow funds to accumulate for dismantlement. Incremental dismantlement was begun in 1997 of steam systems and based on the successful work to date, the Sacramento Municipal Utility District (SMUD) board of directors approved full decommissioning in July 1999. A schedule has been developed for completion of decommissioning by 2008, allowing decommissioning funds to accumulate until they are needed. Systems removal began in the Auxiliary Building in October of 1999 and in the Reactor Building in January of 2000. Systems dismantlement continues in the Reactor Building and the Auxiliary Building and should be completed by mid 2003. The Spent Fuel is currently being moved to dry storage in an onsite ISFSI, with completion scheduled for late 2002. The personnel resources on site are currently assigned to support both the dry fuel project and the dismantlement of the facility. Once fuel movement is complete more resources will be provided for dismantlement. Characterization of major components other than the vessel is complete and planning for their removal is in progress with various cut-up and/or shipping options being evaluated. Planning for the vessel and …
Date: February 27, 2002
Creator: Gardiner, Dennis E.; Newey, Joel M & Snyder, Michael W.
System: The UNT Digital Library
St. Louis FUSRAP-A Strategy for Success (open access)

St. Louis FUSRAP-A Strategy for Success

In October 1997, Congress transferred the Formerly Utilized Sites Remedial Action Program (FUSRAP) from the Department of Energy (DOE) to the United States Army Corps of Engineers (USACE). FUSRAP addresses contamination generated by activities of the Manhattan Engineering District and the Atomic Energy Commission during the 1940's and 50's in support of the nation's nuclear weapons development program. The USACE Operation Order for FUSRAP gave responsibility for remediation of five sites in Missouri and Illinois to the USACESt. Louis District. The principal site is the St. Louis Airport Site (SLAPS), which involves the removal, transportation, disposal, and restoration of approximately 28 acres and 245,000 bank cubic yards (bcy) of contaminated soils. This paper will focus on the progress and achievements in removal action efficiencies of the SLAPS team. This team consists primarily of the USACE and Stone & Webster, Incorporated.
Date: February 27, 2002
Creator: Lyerla, M.; Fox, B.; Chinnock, J.; Haase, A.; Wojinski, S.; Bretz, M. et al.
System: The UNT Digital Library