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Selected Isotopes for Optimized Fuel Assembly Tags (open access)

Selected Isotopes for Optimized Fuel Assembly Tags

In support of our ongoing signatures project we present information on 3 isotopes selected for possible application in optimized tags that could be applied to fuel assemblies to provide an objective measure of burnup. 1. Important factors for an optimized tag are compatibility with the reactor environment (corrosion resistance), low radioactive activation, at least 2 stable isotopes, moderate neutron absorption cross-section, which gives significant changes in isotope ratios over typical fuel assembly irradiation levels, and ease of measurement in the SIMS machine 2. From the candidate isotopes presented in the 3rd FY 08 Quarterly Report, the most promising appear to be Titanium, Hafnium, and Platinum. The other candidate isotopes (Iron, Tungsten, exhibited inadequate corrosion resistance and/or had neutron capture cross-sections either too high or too low for the burnup range of interest.
Date: October 1, 2008
Creator: Gerlach, David C.; Mitchell, Mark R.; Reid, Bruce D.; Gesh, Christopher J. & Hurley, David E.
Object Type: Report
System: The UNT Digital Library
Finite Size Effects on the Real-Space Pair Distribution Function of Nanoparticles (open access)

Finite Size Effects on the Real-Space Pair Distribution Function of Nanoparticles

The pair distribution function (PDF) method is a powerful approach for the analysis of the structure of nanoparticles. An important approximation used in nanoparticle PDF simulations is the incorporation of a form factor describing nanoparticle size and shape. The precise effect of the form factor on the PDF is determined by both particle shape and structure if these characteristics are both anisotropic and correlated. The correct incorporation of finite size effects is important for distinguishing and quantifying the structural consequences of small particle size in nanomaterials.
Date: October 1, 2008
Creator: Gilbert, Benjamin
Object Type: Article
System: The UNT Digital Library
Building America Best Practices Series: Guide to Determining Climate Regions by County (open access)

Building America Best Practices Series: Guide to Determining Climate Regions by County

This document describes the eight climate region designations used by the US Department of Energy Building America Program. In addition to describing the climate zones, the document includes a complete list of every county in the United States and their climate region designations. The county lists are grouped by state. The doucment is intended to assist builders to easily identify what climate region they are building in and therefore which climate-specific Building America best practices guide would be most appropriate for them.
Date: October 1, 2008
Creator: Gilbride, Theresa L.
Object Type: Report
System: The UNT Digital Library
Probing mSUGRA with a Search for Chargino-Neutralino Production using Trileptons (open access)

Probing mSUGRA with a Search for Chargino-Neutralino Production using Trileptons

This thesis describes the CDF II 2 fb{sup -1} search for supersymmetric chargino-neutralino production in {radical}s = 1.96TeV p{bar p} collisions using the 'golden' channel with three leptons and missing transverse energy in the final state and the application of the results to obtain a limit on the parameter space of the supersymmetric model mSUGRA. Electrons and muons are reconstructed directly; isolated tracks are used as a proxy for {tau} leptons. Several analysis channels with different signal purity are defined and evaluated independently. Based on 7 observed and 6.4 expected background events this analysis was able set the first direct limits on chargino-neutralino production in mSUGRA since LEP. Based on mSUGRA phenomenology the sensitivity of this analysis is investigated; the mSUGRA parameter space is split into different phenomenology classes. Experimental results from previous searches in this channel by CDF and D0 have been presented for specific parameter values of a given model. A more model-independent approach is proposed and, by splitting the results of this analysis into channels based on {tau} content, the results of the analysis are generalized.
Date: October 1, 2008
Creator: Glatzer, Julian
Object Type: Report
System: The UNT Digital Library
Bootstrapping a Sustainable North American PEM Fuel Cell Industry: Could a Federal Acquisition Program Make a Difference? (open access)

Bootstrapping a Sustainable North American PEM Fuel Cell Industry: Could a Federal Acquisition Program Make a Difference?

The North American Proton Exchange Membrane (PEM) fuel cell industry may be at a critical juncture. A large-scale market for automotive fuel cells appears to be several years away and in any case will require a long-term, coordinated commitment by government and industry to insure the co-evolution of hydrogen infrastructure and fuel cell vehicles (Greene et al., 2008). The market for non-automotive PEM fuel cells, on the other hand, may be much closer to commercial viability (Stone, 2006). Cost targets are less demanding and manufacturers appear to be close, perhaps within a factor of two, of meeting them. Hydrogen supply is a significant obstacle to market acceptance but may not be as great a barrier as it is for hydrogen-powered vehicles due to the smaller quantities of hydrogen required. PEM fuel cells appear to be potentially competitive in two markets: (1) Backup power (BuP) supply, and (2) electrically-powered MHE (Mahadevan et al., 2007a, 2007b). There are several Original Equipment Manufacturers (OEMs) of PEM fuel cell systems for these applications but production levels have been quite low (on the order of 100-200 per year) and cumulative production experience is also limited (on the order of 1,000 units to date). As a …
Date: October 1, 2008
Creator: Greene, David L & Duleep, Dr. K. G.
Object Type: Report
System: The UNT Digital Library
Irradiation of the First Advanced Gas Reactor Fuel Development and Qualification Experiment in the Advanced Test Reactor (open access)

Irradiation of the First Advanced Gas Reactor Fuel Development and Qualification Experiment in the Advanced Test Reactor

The United States Department of Energy’s Advanced Gas Reactor (AGR) Fuel Development and Qualification Program will be irradiating eight separate tri-isotopic (TRISO) particle fuel (in compact form) experiments in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). These irradiations and fuel development are being accomplished to support development of the next generation reactors in the United States. The ATR has a long history of irradiation testing in support of reactor development and the INL has been designated as the United States Department of Energy’s lead laboratory for nuclear energy development. These AGR fuel experiments will be irradiated over the next ten years to demonstrate and qualify new particle fuel for use in high temperature gas reactors. The experiments, which will each consist of six separate capsules, will be irradiated in an inert sweep gas atmosphere with individual on-line temperature monitoring and control for each capsule. The swept gas will also have on-line fission product monitoring to track performance of the fuel in each individual capsule during irradiation. The design of the first experiment (designated AGR-1) was completed in 2005, and the fabrication and assembly of the test train as well as the support systems and fission …
Date: October 1, 2008
Creator: Grover, S. Blaine & Petti, David A.
Object Type: Article
System: The UNT Digital Library
A User Driven Dynamic Circuit Network Implementation (open access)

A User Driven Dynamic Circuit Network Implementation

The requirements for network predictability are becoming increasingly critical to the DoE science community where resources are widely distributed and collaborations are world-wide. To accommodate these emerging requirements, the Energy Sciences Network has established a Science Data Network to provide user driven guaranteed bandwidth allocations. In this paper we outline the design, implementation, and secure coordinated use of such a network, as well as some lessons learned.
Date: October 1, 2008
Creator: Guok, Chin; Robertson, David; Chaniotakis, Evangelos; Thompson, Mary; Johnston, William & Tierney, Brian
Object Type: Article
System: The UNT Digital Library
Peer review of the National Transportation Safety Board structural analysis of the I-35W bridge collapse. (open access)

Peer review of the National Transportation Safety Board structural analysis of the I-35W bridge collapse.

The Engineering Sciences Center at Sandia National Laboratories provided an independent peer review of the structural analysis supporting the National Transportation Safety Board investigation of the August 1, 2007 collapse of the I-35W Bridge in Minneapolis. The purpose of the review was to provide an impartial critique of the analysis approach, assumptions, solution techniques, and conclusions. Subsequent to reviewing numerous supporting documents, a SNL team of staff and management visited NTSB to participate in analysis briefings, discussions with investigators, and examination of critical elements of the bridge wreckage. This report summarizes the opinion of the review team that the NTSB analysis effort was appropriate and provides compelling supporting evidence for the NTSB probable cause conclusion.
Date: October 1, 2008
Creator: Gwinn, Kenneth West; Redmond, James Michael & Wellman, Gerald William
Object Type: Report
System: The UNT Digital Library
Ferrite HOM Absorber for the RHIC ERL (open access)

Ferrite HOM Absorber for the RHIC ERL

N/A
Date: October 1, 2008
Creator: H., Hahn; Choi, E. M. & Hammons, L.
Object Type: Report
System: The UNT Digital Library
Matrix solution to longitudinal impedance of multi-layer circular structures (open access)

Matrix solution to longitudinal impedance of multi-layer circular structures

A matrix method in which radial wave propagation is treated in analogy to longitudinal transmission lines is presented and applied to finding the longitudinal coupling impedance of axially symmetric multi-layer beam tubes. The method is demonstrated in the case of a Higher Order Mode ferrite absorber with an inserted coated ceramic beam tube. The screening of the ferrite damping properties by the dielectric beam tube is discussed.
Date: October 1, 2008
Creator: Hahn,H.
Object Type: Report
System: The UNT Digital Library
Ferrite HOM Absorber for the RHIC ERL (open access)

Ferrite HOM Absorber for the RHIC ERL

A superconducting Energy Recovery Linac is under construction at Brookhaven National Laboratory to serve as test bed for RHIC upgrades. The damping of higher-order modes in the superconducting five-cell cavity for the Energy-Recovery linac at RHIC is performed exclusively by two ferrite absorbers. The ferrite properties have been measured in ferrite-loaded pill box cavities resulting in the permeability values given by a first-order Debye model for the tiled absorber structure and an equivalent permeability value for computer simulations with solid ring dampers. Measured and simulated results for the higher-order modes in the prototype copper cavity are discussed. First room-temperature measurements of the finished niobium cavity are presented which confirm the effective damping of higher-order modes in the ERL. by the ferrite absorbers.
Date: October 1, 2008
Creator: Hahn,H.; Choi, E.M. & Hammons, L.
Object Type: Report
System: The UNT Digital Library
Project X and its connection to neutrino physics (open access)

Project X and its connection to neutrino physics

Project X is a new high intensity proton source that is being planned at Fermilab to usher in a new era of high intensity physics. The high intensity frontier can provide a wealth of new measurements--the most voracious consumer of protons is the long baseline neutrino program, but with the proton source upgrades being planned there are even more protons available than current neutrino targets can withstand. Those protons can provide a rich program on their own of muon physics and neutrino scattering physics that is complimentary to the long baseline program. In this article we discuss the physics motivation for Project X that comes from these short baseline experiments, and also the status of the design of this new source and what it will take to move forward on that design.
Date: October 1, 2008
Creator: Harris, Deborah & Jansson, Andreas
Object Type: Article
System: The UNT Digital Library
3D CFD Electrochemical and Heat Transfer Model of an Integrated-Planar Solid Oxide Electrolysis Cells (open access)

3D CFD Electrochemical and Heat Transfer Model of an Integrated-Planar Solid Oxide Electrolysis Cells

A three-dimensional computational fluid dynamics (CFD) electrochemical model has been created to model high-temperature electrolysis cell performance and steam electrolysis in a new novel integrated planar porous-tube supported solid oxide electrolysis cell (SOEC). The model is of several integrated planar cells attached to a ceramic support tube. This design is being evaluated with modeling at the Idaho National Laboratory. Mass, momentum, energy, and species conservation and transport are provided via the core features of the commercial CFD code FLUENT. A solid-oxide fuel cell (SOFC) model adds the electrochemical reactions and loss mechanisms and computation of the electric field throughout the cell. The FLUENT SOFC user-defined subroutine was modified for this work to allow for operation in the SOEC mode. Model results provide detailed profiles of temperature, Nernst potential, operating potential, activation over-potential, anode-side gas composition, cathode-side gas composition, current density and hydrogen production over a range of stack operating conditions. Mean per-cell area-specific-resistance (ASR) values decrease with increasing current density. Predicted mean outlet hydrogen and steam concentrations vary linearly with current density, as expected. Effects of variations in operating temperature, gas flow rate, cathode and anode exchange current density, and contact resistance from the base case are presented. Contour plots …
Date: October 1, 2008
Creator: Hawkes, Grant & O'Brien, James E.
Object Type: Article
System: The UNT Digital Library
Benefits and technological challenges in the implementation of TiO2-based ultraviolet photocatalytic oxidation (UVPCO) air cleaners (open access)

Benefits and technological challenges in the implementation of TiO2-based ultraviolet photocatalytic oxidation (UVPCO) air cleaners

Heating, ventilating, and cooling classrooms in California consume substantial electrical energy. Indoor air quality (IAQ) in classrooms affects student health and performance. In addition to airborne pollutants that are emitted directly by indoor sources and those generated outdoors, secondary pollutants can be formed indoors by chemical reaction of ozone with other chemicals and materials. Filters are used in nearly all classroom heating, ventilation and air-conditioning (HVAC) systems to maintain energy-efficient HVAC performance and improve indoor air quality; however, recent evidence indicates that ozone reactions with filters may, in fact, be a source of secondary pollutants. This project quantitatively evaluated ozone deposition in HVAC filters and byproduct formation, and provided a preliminary assessment of the extent to which filter systems are degrading indoor air quality. The preliminary information obtained will contribute to the design of subsequent research efforts and the identification of energy efficient solutions that improve indoor air quality in classrooms and the health and performance of students.
Date: October 1, 2008
Creator: Hodgson, Al; Destaillats, Hugo; Hotchi, Toshifumi & Fisk, William J.
Object Type: Report
System: The UNT Digital Library
The Haitian Economy and the HOPE Act (open access)

The Haitian Economy and the HOPE Act

This report discusses the HOPE Act as it relates to the Haitian economy and U.S. trade policy. In providing preferential access to Haitian apparel imports, the HOPE Act, as amended, gives Haitian firms a competitive (price) advantage over other foreign producers who must pay U.S. duties on apparel exports made from yarns and fabrics supplied by non-regional (e.g., Asian) producers.
Date: October 1, 2008
Creator: Hornbeck, J. F.
Object Type: Report
System: The UNT Digital Library
Novel High Efficiency Photovoltaic Devices Based on the III-N Material System: Final Technical Report, 7 December 2005 - 29 August 2008 (open access)

Novel High Efficiency Photovoltaic Devices Based on the III-N Material System: Final Technical Report, 7 December 2005 - 29 August 2008

The research shows that InGaN material system can be used to realize high-efficiency solar cells, making contributions to growth, modeling, understanding of loss mechanisms, and process optimization.
Date: October 1, 2008
Creator: Hornsberg, C.; Doolittle, W. A. & Ferguson, I.
Object Type: Report
System: The UNT Digital Library
Characterising and modelling the excavation damaged zone (EDZ) in crystalline rock in the context of radioactive waste disposal (open access)

Characterising and modelling the excavation damaged zone (EDZ) in crystalline rock in the context of radioactive waste disposal

This paper describes current knowledge about the nature of and potential for thermo-hydro-mechanical-chemical modelling of the Excavation Damaged Zone (EDZ) around the excavations for an underground radioactive waste repository. In the first part of the paper, the disturbances associated with excavation are explained, together with reviews of Workshops that have been held on the subject. In the second part of the paper, the results of a DECOVALEX research programme on modelling the EDZ are presented. Four research teams used four different models to simulate the complete stress-strain curve for Avro granite from the Swedish Aespoe Hard Rock Laboratory. Subsequent research extended the work to computer simulation of the evolution of the repository using a 'wall block model' and a 'near-field model'. This included assessing the evolution of stress, failure and permeability and time dependent effects during repository evolution. As discussed, all the computer models are well suited to sensitivity studies for evaluating the influence of their respective supporting parameters on the complete stress-strain curve for rock and for modelling the EDZ.
Date: October 1, 2008
Creator: Hudson, J. A.; Backstrom, A.; Rutqvist, J.; Jing, L.; Backers, T.; Chijimatsu, M. et al.
Object Type: Article
System: The UNT Digital Library
Mannford Eagle (Mannford, Okla.), Vol. 25, No. 127, Ed. 1 Wednesday, October 1, 2008 (open access)

Mannford Eagle (Mannford, Okla.), Vol. 25, No. 127, Ed. 1 Wednesday, October 1, 2008

Weekly newspaper from Mannford, Oklahoma that includes local, state, and national news along with advertising.
Date: October 1, 2008
Creator: Hughes, Dustin
Object Type: Newspaper
System: The Gateway to Oklahoma History
Data Compilation for AGR-3/4 Designed-to-Fail (DTF) Fuel Particle Batch LEU04-02DTF (open access)

Data Compilation for AGR-3/4 Designed-to-Fail (DTF) Fuel Particle Batch LEU04-02DTF

This document is a compilation of coating and characterization data for the AGR-3/4 designed-to-fail (DTF) particles. The DTF coating is a high density, high anisotropy pyrocarbon coating of nominal 20 {micro}m thickness that is deposited directly on the kernel. The purpose of this coating is to fail early in the irradiation, resulting in a controlled release of fission products which can be analyzed to provide data on fission product transport. A small number of DTF particles will be included with standard TRISO driver fuel particles in the AGR-3 and AGR-4 compacts. The ORNL Coated Particle Fuel Development Laboratory 50-mm diameter fluidized bed coater was used to coat the DTF particles. The coatings were produced using procedures and process parameters that were developed in an earlier phase of the project as documented in 'Summary Report on the Development of Procedures for the Fabrication of AGR-3/4 Design-to-Fail Particles', ORNL/TM-2008/161. Two coating runs were conducted using the approved coating parameters. NUCO425-06DTF was a final process qualification batch using natural enrichment uranium carbide/uranium oxide (UCO) kernels. After the qualification run, LEU04-02DTF was produced using low enriched UCO kernels. Both runs were inspected and determined to meet the specifications for DTF particles in section 5 …
Date: October 1, 2008
Creator: Hunn, John D & Miller, James Henry
Object Type: Report
System: The UNT Digital Library
.China’s Policies and Actions for Addressing Climate Change (open access)

.China’s Policies and Actions for Addressing Climate Change

.China has formulated and implemented its national climate change programme, and adopted a series of policies and measures in this regard. China addresses climate change in the context of implementing sustainable development strategy, combined with its accelerated steps to build a resource-conserving and environmental-friendly society and an innovation-oriented country.
Date: October 1, 2008
Creator: Information Office of the State Council of the People’s Republic of China
Object Type: Text
System: The UNT Digital Library
Very Large System Dynamics Models - Lessons Learned (open access)

Very Large System Dynamics Models - Lessons Learned

This paper provides lessons learned from developing several large system dynamics (SD) models. System dynamics modeling practice emphasize the need to keep models small so that they are manageable and understandable. This practice is generally reasonable and prudent; however, there are times that large SD models are necessary. This paper outlines two large SD projects that were done at two Department of Energy National Laboratories, the Idaho National Laboratory and Sandia National Laboratories. This paper summarizes the models and then discusses some of the valuable lessons learned during these two modeling efforts.
Date: October 1, 2008
Creator: Jacobson, Jacob J. & Malczynski, Leonard
Object Type: Article
System: The UNT Digital Library
MI Gap Clearing Kicker Magnet Design Review (open access)

MI Gap Clearing Kicker Magnet Design Review

The kicker system requirements were originally conceived for the NOvA project. NOvA is a neutrino experiment located in Minnesota. To achieve the desired neutrino flux several upgrades are required to the accelerator complex. The Recycler will be used as a proton pre-injector for the Main Injector (MI). As the Recycler is the same size as the MI, it is possible to do a single turn fill ({approx}11 {micro}sec), minimizing the proton injection time in the MI cycle and maximizing the protons on target. The Recycler can then be filled with beam while the MI is ramping to extract beam to the target. To do this requires two new transfer lines. The existing Recycler injection line was designed for 10{pi} pbar beams, not the 20{pi} proton beams we anticipate from the Booster. The existing Recycler extraction line allows for proton injection through the MI, while we want direct injection from the Booster. These two lines will be decommissioned. The new injection line from the MI8 line into the Recycler will start at 848 and end with injection kickers at RR104. The new extraction line in the RR30 straight section will start with a new extraction kicker at RR232 and end with …
Date: October 1, 2008
Creator: Jensen, Chris
Object Type: Report
System: The UNT Digital Library
Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2007 (open access)

Evaluating Cumulative Ecosystem Response to Restoration Projects in the Columbia River Estuary, Annual Report 2007

The goal of this multi-year study (2004-2010) is to develop a methodology to evaluate the cumulative effects of multiple habitat restoration projects intended to benefit ecosystems supporting juvenile salmonids in the lower Columbia River and estuary. Literature review in 2004 revealed no existing methods for such an evaluation and suggested that cumulative effects could be additive or synergistic. Field research in 2005, 2006, and 2007 involved intensive, comparative studies paired by habitat type (tidal swamp vs. marsh), trajectory (restoration vs. reference site), and restoration action (tide gate vs. culvert vs. dike breach). The field work established two kinds of monitoring indicators for eventual cumulative effects analysis: core and higher-order indicators. Management implications of limitations and applications of site-specific effectiveness monitoring and cumulative effects analysis were identified.
Date: October 1, 2008
Creator: Johnson, Gary E.; Diefenderfer, Heida L.; Borde, Amy B.; Dawley, Earl M.; Ebberts, Blaine D.; Putman, Douglas A. et al.
Object Type: Report
System: The UNT Digital Library
Analysis and Measurement of Bubble Dynamics and Associated Flow Field in Subcooled Nucleate Boiling Flows (open access)

Analysis and Measurement of Bubble Dynamics and Associated Flow Field in Subcooled Nucleate Boiling Flows

In recent years, subooled nucleate boiling (SNB) has attrcted expanding research interest owing to the emergence of axial offset anomaly (AOA) or crud-induced power shigt (CIPS) in many operating US PWRs, which is an unexpected deviation in the core axial power distribution from the predicted power curves. Research indicates that the formation of the crud, which directly leads to AOA phenomena, results from the presence of the subcooled nucleate boiling, and is especially realted to bubble motion occurring in the core region.
Date: October 1, 2008
Creator: Jones, Barclay G.
Object Type: Report
System: The UNT Digital Library