618-10 Burial Ground VPU Nonintrusive Characterization Process and Data Collection Workshop (open access)

618-10 Burial Ground VPU Nonintrusive Characterization Process and Data Collection Workshop

This report presents the nonintrusive characterization measurement results for the 618-10 Burial Ground and provides a general assessment of the estimated dose, isotopic concentrations, and bounding transuranic radionuclide inventories for the 618-10 vertical pipe units and trenches, based on interpretation of data from a system of in situ radiological multi-detector probes.
Date: December 21, 2010
Creator: Khabir, S.
Object Type: Report
System: The UNT Digital Library
Advantages of a soft protective layer for good signal-to-noise ratio proton radiographs in high debris environments (open access)

Advantages of a soft protective layer for good signal-to-noise ratio proton radiographs in high debris environments

None
Date: December 21, 2010
Creator: Le Galloudec, N. R.; Cobble, J.; Nelson, S. L.; Merwin, A.; Paudel, Y.; Shrestha, I. et al.
Object Type: Article
System: The UNT Digital Library
Analysis of Radioactive Releases During Proposed Demolition Activities for the 224-U and 224-UA Buildings - Addendum (open access)

Analysis of Radioactive Releases During Proposed Demolition Activities for the 224-U and 224-UA Buildings - Addendum

A post-demolition modeling analysis is conducted that compares during-demolition atmospheric concentration monitoring results with modeling results based on the actual meteorological conditions during the demolition activities. The 224-U and 224-UA Buildings that were located in the U-Plant UO3 complex in the 200 West Area of the Hanford Site were demolished during the summer of 2010. These facilities converted uranyl nitrate hexahydrate (UNH), a product of Hanford’s Plutonium-Uranium Extraction (PUREX) Plant, into uranium trioxide (UO3). This report is an addendum to a pre-demolition emission analysis and air dispersion modeling effort that was conducted for proposed demolition activities for these structures.
Date: December 21, 2010
Creator: Napier, Bruce A.; Rishel, Jeremy P.; Droppo, James G.; Joyce, Kevin E. & Strom, Daniel J.
Object Type: Report
System: The UNT Digital Library
CHARACTERIZATION OF MODIFIED MONOSODIUM TITANATE - AN IMPROVED SORBENT FOR STRONTIUM AND ACTINIDE SEPARATIONS (open access)

CHARACTERIZATION OF MODIFIED MONOSODIUM TITANATE - AN IMPROVED SORBENT FOR STRONTIUM AND ACTINIDE SEPARATIONS

High-level nuclear waste produced from fuel reprocessing operations at the Savannah River Site (SRS) requires pretreatment to remove {sup 134,137}Cs, {sup 90}Sr, and alpha-emitting radionuclides (i.e., actinides) prior to disposal onsite as low level waste. An inorganic sorbent, monosodium titanate (MST), is currently used to remove {sup 90}Sr and alpha-emitting radionuclides, while a caustic-side solvent extraction process is used for removing {sup 134,137}Cs. A new peroxotitanate material, modified MST, or mMST, has recently been developed and has shown increased removal kinetics and capacity for {sup 90}Sr and alpha-emitting radionuclides compared to the current baseline material, MST. This paper describes recent results focused on further characterization of this material.
Date: December 21, 2010
Creator: Hobbs, D.; Taylor-Pashow, K. & Missimer, D.
Object Type: Article
System: The UNT Digital Library
Compliance Monitoring of Juvenile Subyearling Chinook Salmon Survival and Passage at The Dalles Dam, Summer 2010 (open access)

Compliance Monitoring of Juvenile Subyearling Chinook Salmon Survival and Passage at The Dalles Dam, Summer 2010

The purpose of this compliance study was to estimate dam passage survival of subyearling Chinook salmon smolts at The Dalles Dam during summer 2010. Under the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp), dam passage survival should be greater than or equal to 0.93 and estimated with a standard error (SE) less than or equal 0.015. The study also estimated smolt passage survival from the forebay 2 km upstream of the dam to the tailrace 2 km below the dam The forebay-to-tailrace survival estimate satisfies the “BRZ-to-BRZ” survival estimate called for in the Fish Accords. , as well as the forebay residence time, tailrace egress time, and spill passage efficiency, as required in the Columbia Basin Fish Accords. The estimate of dam survival for subyearling Chinook salmon at The Dalles in 2010 was 0.9404 with an associated standard error of 0.0091.
Date: December 21, 2010
Creator: Johnson, Gary E.; Carlson, Thomas J. & Skalski, John R.
Object Type: Report
System: The UNT Digital Library
Direct observation of imprinted antiferromagnetic vortex state in CoO/Fe/Ag(001) disks (open access)

Direct observation of imprinted antiferromagnetic vortex state in CoO/Fe/Ag(001) disks

In magnetic thin films, a magnetic vortex is a state in which the magnetization vector curls around the center of a confined structure. A vortex state in a thin film disk, for example, is a topological object characterized by the vortex polarity and the winding number. In ferromagnetic (FM) disks, these parameters govern many fundamental properties of the vortex such as its gyroscopic rotation, polarity reversal, core motion, and vortex pair excitation. However, in antiferromagnetic (AFM) disks, though there has been indirect evidence of the vortex state through observations of the induced FM-ordered spins in the AFM disk, they have never been observed directly in experiment. By fabricating single crystalline NiO/Fe/Ag(001) and CoO/Fe/Ag(001) disks and using X-ray Magnetic Linear Dichroism (XMLD), we show direct observation of the vortex state in an AFM disk of AFM/FM bilayer system. We observe that there are two types of AFM vortices, one of which has no analog in FM structures. Finally, we show that a frozen AFM vortex can bias a FM vortex at low temperature.
Date: December 21, 2010
Creator: Wu, J.; Carlton, D.; Park, J. S.; Meng, Y.; Arenholz, E.; Doran, A. et al.
Object Type: Article
System: The UNT Digital Library
Energy Audit Practices in China: National and Local Experiences and Issues (open access)

Energy Audit Practices in China: National and Local Experiences and Issues

China has set an ambitious goal of reducing its energy use per unit of GDP by 20% between 2006 and 2010. Since the industrial sector consumes about two-thirds of China's primary energy, many of the country's efforts are focused on improving the energy efficiency of this sector. Industrial energy audits have become an important part of China's efforts to improve its energy intensity. In China, industrial energy audits have been employed to help enterprises indentify energy-efficiency improvement opportunities for achieving the energy-saving targets. These audits also serve as a mean to collect critical energy-consuming information necessary for governments at different levels to supervise enterprises energy use and evaluate their energy performance. To better understand how energy audits are carried out in China as well as their impacts on achieving China's energy-saving target, researchers at the Lawrence Berkeley National Laboratory (LBNL) conducted an in-depth study that combines a review of China's national policies and guidelines on energy auditing and a series of discussions with a variety of Chinese institutions involved in energy audits. This report consists of four parts. First, it provides a historical overview of energy auditing in China over the past decades, describing how and why energy audits have …
Date: December 21, 2010
Creator: Shen, Bo; Price, Lynn & Lu, Hongyou
Object Type: Report
System: The UNT Digital Library
Optimization of Rhodium-Based Catalysts for Mixed Alcohol Synthesis -- 2009 Progress Report (open access)

Optimization of Rhodium-Based Catalysts for Mixed Alcohol Synthesis -- 2009 Progress Report

Pacific Northwest National Laboratory (PNNL) has been conducting research for the United States Department of Energy, Energy Efficiency Renewable Energy, Biomass Program to investigate the feasibility of producing mixed alcohols from biomass-derived synthesis gas (syngas). This research has involved the screening of potential catalysts, and optimization of the more promising ones, using laboratory scale reactors. During 2009, the main goal of the testing program focused on optimizing selected supported catalysts containing rhodium (Rh) and manganese (Mn). Optimization involved examining different total concentrations and atomic ratios of Rh and Mn as well as that of the more promising promoters (Ir and Li) identified in the earlier screening studies. Evaluation of catalyst performance focused on attaining improvements with respect to the space-time-yield and converted carbon selectivity to C2+ oxygenates, with additional consideration given to the fraction of the oxygenates that were C2+ alcohols.
Date: December 21, 2010
Creator: Gerber, Mark A.; Gray, Michel J.; Stevens, Don J.; White, J. F. & Rummel, Becky L.
Object Type: Report
System: The UNT Digital Library
Quarkonia as a multi-purpose tool (open access)

Quarkonia as a multi-purpose tool

Quarkonia can be a very useful tool for understanding the medium in which they are produced and pass through. However, their usefulness as a tool depends on how well certain aspects of their behavior in cold matter are understood.
Date: December 21, 2010
Creator: Vogt, R
Object Type: Article
System: The UNT Digital Library
The status of open heavy flavor production at RHIC (open access)

The status of open heavy flavor production at RHIC

We discuss the calculation of open heavy flavor cross sections at RHIC and describe how the semileptonic decays of charm and bottom quarks can be separated.
Date: December 21, 2010
Creator: Vogt, R
Object Type: Article
System: The UNT Digital Library
Development of tools and techniques for momentum compression of fast rare isotopes (open access)

Development of tools and techniques for momentum compression of fast rare isotopes

As part of our past research and development work, we have created and developed the LISE++ simulation code [Tar04, Tar08]. The LISE++ package was significantly extended with the addition of a Monte Carlo option that includes an option for calculating ion trajectories using a Taylor-series expansion up to fifth order, and implementation of the MOTER Monte Carlo code [Kow87] for ray tracing of the ions into the suite of LISE++ codes. The MOTER code was rewritten from FORTRAN into C++ and transported to the MS-Windows operating system. Extensive work went into the creation of a user-friendly interface for the code. An example of the graphical user interface created for the MOTER code is shown in the left panel of Figure 1 and the results of a typical calculation for the trajectories of particles that pass through the A1900 fragment separator are shown in the right panel. The MOTER code is presently included as part of the LISE++ package for downloading without restriction by the worldwide community. The LISE++ was extensively developed and generalized to apply to any projectile fragment separator during the early phase of this grant. In addition to the inclusion of the MOTER code, other important additions to …
Date: November 21, 2010
Creator: Morrissey, David J.; Sherrill, Bradley M. & Tarasov, Oleg
Object Type: Report
System: The UNT Digital Library
An Assessment of Molecular Dynamic Force Fields for Silica for Use in Simulating Laser Damage Mitigation (open access)

An Assessment of Molecular Dynamic Force Fields for Silica for Use in Simulating Laser Damage Mitigation

We compare force fields (FF's) that have been used in molecular dynamic (MD) simulations of silica in order to assess their applicability for use in simulating IR-laser damage mitigation. Although pairwise FF?s obtained by fitting quantum mechanical calculations such as the BKS and CHIK potentials have been shown to reproduce many of the properties of silica including the stability of silica polymorphs and the densification of the liquid, we show that melting temperatures and fictive temperatures are much too high. Softer empirical force fields give liquid and glass properties at experimental temperatures but may not predict all properties important to laser mitigation experiments.
Date: October 21, 2010
Creator: Soules, T F; Gilmer, G H; Matthews, M J; Stolken, J S & Feit, M D
Object Type: Article
System: The UNT Digital Library
Atmospheric Modeling in Support of a Roadway Accident (open access)

Atmospheric Modeling in Support of a Roadway Accident

The United States Forest Service-Savannah River (USFS) routinely performs prescribed fires at the Savannah River Site (SRS), a Department of Energy (DOE) facility located in southwest South Carolina. This facility covers {approx}800 square kilometers and is mainly wooded except for scattered industrial areas containing facilities used in managing nuclear materials for national defense and waste processing. Prescribed fires of forest undergrowth are necessary to reduce the risk of inadvertent wild fires which have the potential to destroy large areas and threaten nuclear facility operations. This paper discusses meteorological observations and numerical model simulations from a period in early 2002 of an incident involving an early-morning multicar accident caused by poor visibility along a major roadway on the northern border of the SRS. At the time of the accident, it was not clear if the limited visibility was due solely to fog or whether smoke from a prescribed burn conducted the previous day just to the northwest of the crash site had contributed to the visibility. Through use of available meteorological information and detailed modeling, it was determined that the primary reason for the low visibility on this night was fog induced by meteorological conditions.
Date: October 21, 2010
Creator: Buckley, R. & Hunter, C.
Object Type: Article
System: The UNT Digital Library
Bimetallic Lithium Borohydrides Toward Reversible Hydrogen Storage (open access)

Bimetallic Lithium Borohydrides Toward Reversible Hydrogen Storage

Borohydrides such as LiBH{sub 4} have been studied as candidates for hydrogen storage because of their high hydrogen contents (18.4 wt% for LiBH{sub 4}). Limited success has been made in reducing the dehydrogenation temperature by adding reactants such as metals, metal oxides and metal halides. However, full rehydrogenation has not been realized because of multi-step decomposition processes and the stable intermediate species produced. It is suggested that adding second cation in LiBH{sub 4} may reduce the binding energy of B-H. The second cation may also provide the pathway for full rehydrogenation. In this work, several bimetallic borohydrides were synthesized using wet chemistry, high pressure reactive ball milling and sintering processes. The investigation found that the thermodynamic stability was reduced, but the full rehydrogenation is still a challenge. Although our experiments show the partial reversibility of the bimetallic borohydrides, it was not sustainable during dehydriding-rehydriding cycles because of the accumulation of hydrogen inert species.
Date: October 21, 2010
Creator: Au, M.
Object Type: Article
System: The UNT Digital Library
Comparing the use of 4.6 um lasers versus 10.6 um lasers for mitigating damage site growth on fused silica surfaces (open access)

Comparing the use of 4.6 um lasers versus 10.6 um lasers for mitigating damage site growth on fused silica surfaces

The advantage of using mid-infrared (IR) 4.6 {micro}m lasers, versus far-infrared 10.6 {micro}m lasers, for mitigating damage growth on fused silica is investigated. In contrast to fused silica's high absorption at 10.6 {micro}m, silica absorption at 4.6 {micro}m is two orders of magnitude less. The much reduced absorption at 4.6 {micro}m enables deep heat penetration into fused silica when it is heated using the mid-IR laser, which in turn leads to more effective mitigation of damage sites with deep cracks. The advantage of using mid-IR versus far-IR laser for damage growth mitigation under non-evaporative condition is quantified by defining a figure of merit (FOM) that relates the crack healing depth to laser power required. Based on our FOM, we show that for damage cracks up to at least 500 {micro}m in depth, mitigation using a 4.6 {micro}m mid-IR laser is more efficient than mitigation using a 10.6 {micro}m far-IR laser.
Date: October 21, 2010
Creator: Yang, S T; Matthews, M J; Elhadj, S; Cooke, D; Guss, G M; Draggoo, V G et al.
Object Type: Article
System: The UNT Digital Library
Densification and residual stress induced by CO2 laser-based mitigation of SiO2 surfaces (open access)

Densification and residual stress induced by CO2 laser-based mitigation of SiO2 surfaces

Knowing the ultimate surface morphology resulting from CO{sub 2} laser mitigation of induced laser damage is important both for determining adequate treatment protocols, and for preventing deleterious intensification upon subsequent illumination of downstream optics. Physical effects such as evaporation, viscous flow and densification can strongly affect the final morphology of the treated site. Evaporation is a strong function of temperature and will play a leading role in determining pit shapes when the evaporation rate is large, both because of material loss and redeposition. Viscous motion of the hot molten material during heating and cooling can redistribute material due to surface tension gradients (Marangoni effect) and vapor recoil pressure effects. Less well known, perhaps, is that silica can densify as a result of structural relaxation, to a degree depending on the local thermal history. The specific volume shrinkage due to structural relaxation can be mistaken for material loss due to evaporation. Unlike evaporation, however, local density change can be reversed by post annealing. All of these effects must be taken into account to adequately describe the final morphology and optical properties of single and multiple-pass mitigation protocols. We have investigated, experimentally and theoretically, the significance of such densification on residual stress …
Date: October 21, 2010
Creator: Feit, M D; Matthews, M J; Soules, T F & Stolken, J S
Object Type: Article
System: The UNT Digital Library

Durability of Poly (Methyl Methacrylate) Lenses Used in Concentrating Photovoltaics

This presentation reports the findings of NREL's screen test to characterize the durability of poly (methyl methacrylate) lenses used in concentrated photovoltaics.
Date: October 21, 2010
Creator: Miller, D.; Gedvilas, L.; To, B.; Kennedy, C. & Kurtz, S.
Object Type: Presentation
System: The UNT Digital Library
Energy Efficiency Improvement and Cost Saving Opportunities for the U.S. Iron and Steel Industry An ENERGY STAR(R) Guide for Energy and Plant Managers (open access)

Energy Efficiency Improvement and Cost Saving Opportunities for the U.S. Iron and Steel Industry An ENERGY STAR(R) Guide for Energy and Plant Managers

Energy is an important cost factor in the U.S iron and steel industry. Energy efficiency improvement is an important way to reduce these costs and to increase predictable earnings, especially in times of high energy price volatility. There are a variety of opportunities available at individual plants in the U.S. iron and steel industry to reduce energy consumption in a cost-effective manner. This Energy Guide discusses energy efficiency practices and energy-efficient technologies that can be implemented at the component, process, facility, and organizational levels. A discussion of the structure, production trends, energy consumption, and greenhouse gas emissions of the iron and steel industry is provided along with a description of the major process technologies used within the industry. Next, a wide variety of energy efficiency measures are described. Many measure descriptions include expected savings in energy and energy-related costs, based on case study data from real-world applications in the steel and related industries worldwide. Typical measure payback periods and references to further information in the technical literature are also provided, when available. The information in this Energy Guide is intended to help energy and plant managers in the U.S. iron and steel industry reduce energy consumption and greenhouse gas emissions …
Date: October 21, 2010
Creator: Worrell, Ernst; Blinde, Paul; Neelis, Maarten; Blomen, Eliane & Masanet, Eric
Object Type: Report
System: The UNT Digital Library
Energy Efficiency Services Sector: Workforce Size and Expectations for Growth (open access)

Energy Efficiency Services Sector: Workforce Size and Expectations for Growth

None
Date: October 21, 2010
Creator: Goldman, Charles; Fuller, Merrian C.; Stuart, Elizabeth; Peters, Jane S.; McRae, Marjorie; Albers, Nathaniel et al.
Object Type: Report
System: The UNT Digital Library
An Improved Method of Mitigating Laser Induced Surface Damage Growth in Fused Silica Using a Rastered, Pulsed CO2 Laser (open access)

An Improved Method of Mitigating Laser Induced Surface Damage Growth in Fused Silica Using a Rastered, Pulsed CO2 Laser

A new method of mitigating (arresting) the growth of large (>200 m diameter and depth) laser induced surface damage on fused silica has been developed that successfully addresses several issues encountered with our previously-reported large site mitigation technique. As in the previous work, a tightly-focused 10.6 {micro}m CO{sub 2} laser spot is scanned over the damage site by galvanometer steering mirrors. In contrast to the previous work, the laser is pulsed instead of CW, with the pulse length and repetition frequency chosen to allow substantial cooling between pulses. This cooling has the important effect of reducing the heat-affected zone capable of supporting thermo-capillary flow from scale lengths on the order of the overall scan pattern to scale lengths on the order of the focused laser spot, thus preventing the formation of a raised rim around the final mitigation site and its consequent down-stream intensification. Other advantages of the new method include lower residual stresses, and improved damage threshold associated with reduced amounts of redeposited material. The raster patterns can be designed to produce specific shapes of the mitigation pit including cones and pyramids. Details of the new technique and its comparison with the previous technique will be presented.
Date: October 21, 2010
Creator: Bass, I L; Guss, G M; Nostrand, M J & Wegner, P L
Object Type: Article
System: The UNT Digital Library
Memory-bit selection and recording by rotating fields in vortex-core cross-point architecture (open access)

Memory-bit selection and recording by rotating fields in vortex-core cross-point architecture

In one of our earlier studies [Appl. Phys. Lett. 92, 022509 (2008)], we proposed a concept of robust information storage, recording and readout, which can be implementaed in nonvolatile magnetic random-access memories and is based on the energetically degenerated twofold ground states of vortex-core magnetizations. In the present study, we experimentally demonstrate reliable memory-bit selection and information recording in vortex-core cross-point architecture, specifically using a two-by-two vortex-state disk array. In order to efficiently switch a vortex core positioned at the intersection of crossed electrodes, two orthogonal addressing electrodes are selected, and then two Gaussian pulse currents of optimal pulse width and time delay are applied. Such tailored pulse-type rotating magnetic fields which occurs only at the selected intersection is prerequisite for a reliable memory-bit selection and low-power-consumption recording of information in the existing cross-point architecture.
Date: October 21, 2010
Creator: Yu, Young-Sang; Jung, Hyunsung; Lee, Ki-Suk; Fischer, Peter & Kim, Sang-Koog
Object Type: Article
System: The UNT Digital Library

U.S. Fuel Cell Electric Vehicle Demonstration Project 2010 Status Update

This presentation summarizes U.S. Fuel Cell Electric Vehicle Demonstration Project 2010 Status Update.
Date: October 21, 2010
Creator: Wipke, K.; Sprik, S.; Kurtz, J. & Ramsden, T.
Object Type: Presentation
System: The UNT Digital Library
Data Quality Assessment Report for the Remedial Investigation of Hanford Site Releases to the Columbia River, Hanford Site, Washington (open access)

Data Quality Assessment Report for the Remedial Investigation of Hanford Site Releases to the Columbia River, Hanford Site, Washington

This report summarizes the results of the data quality assessment that was performed on the analytical data generated in connection with the 2008/2009 surface water, sediment, and soil data collection; groundwater upwelling investigation sample collection; and fish tissue sample collection.
Date: September 21, 2010
Creator: Hulstrom, L. C.
Object Type: Report
System: The UNT Digital Library
Effects of Hyperbolic Rotation in Minkowski Space on the Modeling of Plasma Accelerators in a Lorentz Boosted Frame (open access)

Effects of Hyperbolic Rotation in Minkowski Space on the Modeling of Plasma Accelerators in a Lorentz Boosted Frame

Laser driven plasma accelerators promise much shorter particle accelerators but their development requires detailed simulations that challenge or exceed current capabilities. We report the first direct simulations of stages up to 1 TeV from simulations using a Lorentz boosted calculation frame resulting in a million times speedup, thanks to a frame boost as high as gamma = 1300. Effects of the hyperbolic rotation in Minkowski space resulting from the frame boost on the laser propagation in the plasma is shown to be key in the mitigation of a numerical instability that was limiting previous attempts.
Date: September 21, 2010
Creator: Vay, J. L.; Geddes, C. G. R.; Cormier-Michel, E. & Grote, D. P.
Object Type: Article
System: The UNT Digital Library