A Comprehensive Study of Surface Chemistry for Application to Engine NOx Aftertreatment (open access)

A Comprehensive Study of Surface Chemistry for Application to Engine NOx Aftertreatment

This work focuses on developing a scientific understanding of the processes associated with NO{sub x} trap operation. NO{sub x} traps are the most advanced technology for achieving future emissions standards with diesel engines. Successful development of NO{sub x} traps will allow widespread use of diesel engines in light-duty vehicles, reducing oil imports by as much as 60%. Diesel engines have a high efficiency and low maintenance that makes them the ideal choice for transportation applications. Use of diesel engines in all light-duty vehicles would reduce oil consumption in the USA by 30% and oil imports by 60%, considerably improving our energy security. For heavy trucks, there is no viable alternative to diesel engines. Only diesel engines can provide the necessary high efficiency and long life. These benefits are offset by high emission of pollutants. Diesel engines have high emissions of NO{sub x} and particulate matter. Over the last 20 years, EPA has been reducing allowable emissions from diesel engines, and NO{sub x} emissions are scheduled to be cut by a factor of 10 over the next 7 years. The target NO{sub x} emissions for year 2010 is 0.20 g/hp-hr. This value is well below 1 g/hp-hr, which has been identified …
Date: February 19, 2004
Creator: Aceves, S M; Piggot, T; Pitz, W; Mundy, C; Kuo, W & Havstad, M
Object Type: Report
System: The UNT Digital Library
Results of the Excreta Bioassay Quality Control Program For April 1, 2006 Through March 31, 2007 (open access)

Results of the Excreta Bioassay Quality Control Program For April 1, 2006 Through March 31, 2007

A total of 66 urine samples, 6 blank fecal and 6 spiked artificial fecal samples were submitted during the report period (April 1, 2006 through March 31, 2007) to General Engineering Laboratories, South Carolina by the Hanford Internal Dosimetry Program (IDP) to check the accuracy, precision, and detection levels of their analyses. Urine analyses for tritium, Sr, 238Pu, 239Pu, 241Am, 243Am 235U, 238U, elemental uranium and fecal analyses for 241Am, 238Pu and 239Pu were tested this year. The number of QC urine samples submitted during the report period represented 1.7% of the total samples submitted. In addition to the samples provided by IDP, GEL was also required to conduct their own QC program, and submit the results of analyses to IDP. About 36% of the analyses processed by GEL during the second year of this contract were quality control samples. GEL tested the performance of 16 radioisotopes, all of which met or exceeded the specifications in the Statement of Work. IDP concluded that GEL was performing well for all analyses tested, and concerns identified earlier were satisfactorily resolved.
Date: February 19, 2008
Creator: Antonio, Cheryl L.
Object Type: Report
System: The UNT Digital Library
An Innovative Ceramic Corrosion Protection System for Zircaloy Cladding (open access)

An Innovative Ceramic Corrosion Protection System for Zircaloy Cladding

Light Water reactor (LWR) fuel performance is currently limited by thermal, chemical and mechanical constraints associated with the design, fabrication, and operation of the fuel in incore operation. Corrosion of the zirconium based (Zircaloy-4) alloy cladding of the fuel is a primary limiting factor. Recent success at the University of Florida in developing thin ceramic films with great adhesive properties for metal substrates offers an innovative breakthrough for eliminating a major weakness of the Zircaloy clad. ?The University of Florida proposes to coat the existing Zircaloy clad tubes with a ceramic coating for corrosion protection. An added bonus of this approach would be the implementation of a boron-containing burnable poison outer layer will also be demonstrated as part of the ceramic coating development. In this proposed effort, emphasis will be on the ceramic coating with only demonstration of feasibility on the burnable outer coating approach. This proposed program i s expected to give a step change (approximately a doubling) in clad lifetime before failure due to corrosion. In the development of ceramic coatings for Zircaloy-4 clad, silicon carbide and zirconium carbide coatings will first be applied to Zircaloy-4 coupons and cladding samples by thermal assisted chemical vapor deposition, plasma assisted …
Date: February 19, 2003
Creator: Baney, Ronald H.; Tulenko, James S.; Butt, D.; Demkowicz, P.; Fuchs, G.; Schoessow, G. et al.
Object Type: Report
System: The UNT Digital Library
Effects of lattice disorder in the UCu(5-x)Pd(x) system (open access)

Effects of lattice disorder in the UCu(5-x)Pd(x) system

The UCu5-x Pdx system exhibits non-Fermi liquid (NFL) behavior in thermodynamic and transport properties at low temperatures for Pd concentrations 0.9 less than or approximately x less than or approximately 1.5. The local structure around the U, Cu, and Pd atoms has been measured for
Date: February 19, 2002
Creator: Bauer, E. D.; Booth, C. H.; Kwei, G. H.; Chau, R. & Maple, M. B.
Object Type: Article
System: The UNT Digital Library
Evaluation of Mass Transfer Performance for Caustic-Side Solvent Extraction of Cesium in a Conventional 5-cm Centrifugal Contactor (open access)

Evaluation of Mass Transfer Performance for Caustic-Side Solvent Extraction of Cesium in a Conventional 5-cm Centrifugal Contactor

Tests have been conducted to determine if satisfactory mass transfer performance is achieved using a fully pumping 5-cm centrifugal contactor under conditions present in the Caustic-Side Solvent Extraction (CSSX) process. Tests utilized a commercially available contactor that had been modified by installation of a rotor housing bottom that had straight radial vanes on the process side. As received from the vendor, the housing bottom was equipped with curved (impeller-type) vanes that were intended to promote phase separation by minimizing mixing of influent solutions. Stage efficiencies exceeding 85% were obtained under conditions, present in the extraction section of the CSSX flowsheet. Under CSSX stripping conditions the stage efficiency exceeded 90%. In both cases, the efficiencies obtained exceed the minimum requirement for acceptable transfer of cesium in the CSSX process.
Date: February 19, 2002
Creator: Birdwell, Jr. J.F.
Object Type: Report
System: The UNT Digital Library
The Dictyostelium discoideum cellulose synthase: Structure/function analysis and identification of interacting proteins (open access)

The Dictyostelium discoideum cellulose synthase: Structure/function analysis and identification of interacting proteins

OAK-B135 The major accomplishments of this project were: (1) the initial characterization of dcsA, the gene for the putative catalytic subunit of cellulose synthase in the cellular slime mold Dictyostelium discoideum; (2) the detection of a developmentally regulated event (unidentified, but perhaps a protein modification or association with a protein partner) that is required for cellulose synthase activity (i.e., the dcsA product is necessary, but not sufficient for cellulose synthesis); (3) the continued exploration of the developmental context of cellulose synthesis and DcsA; (4) the isolation of a GFP-DcsA-expressing strain (work in progress); and (5) the identification of Dictyostelium homologues for plant genes whose products play roles in cellulose biosynthesis. Although our progress was slow and many of our results negative, we did develop a number of promising avenues of investigation that can serve as the foundation for future projects.
Date: February 19, 2004
Creator: Blanton, Richard L.
Object Type: Report
System: The UNT Digital Library
Rheology Modifiers for Radioactive Waste Slurries (open access)

Rheology Modifiers for Radioactive Waste Slurries

The goals of this study were to determine if trace levels of chemical additives could be used to reduce the rheological characteristics of radioactive waste slurries, identify potential chemical additives for this work and future testing, test a limited set of chemical additive candidates on simulated radioactive wastes, and develop advanced techniques to visualize the internal slurry structure and particle-particle interaction within the slurry.
Date: February 19, 2003
Creator: Calloway, T.B. Jr.
Object Type: Article
System: The UNT Digital Library
A Report on the use of Weak-Shock Wave Profiles and 3-D Dislocation Dynamics Simulations for Validation of Dislocation Multiplication and Mobility in the Phonon Drag Regime (open access)

A Report on the use of Weak-Shock Wave Profiles and 3-D Dislocation Dynamics Simulations for Validation of Dislocation Multiplication and Mobility in the Phonon Drag Regime

Dynamically loaded gas gun experiments were performed to validate the predictive capabilities of 3-D dislocation dynamics (DD) code simulations at very high strain rates and dislocation velocities where the phonon drag mechanism will be dominant. Experiments were performed in the weak-shock regime on high-purity Mo single crystals with [001] compression axes. We have also performed shock-recovery experiments and are in the process of analyzing the dislocation structure generated by the weak-shock using transmission electron microscopy (TEM), which will also be used to validate the dislocation structure predicted by the DD simulations. The DD simulations being performed at Washington State University by Prof. H. Zbib and co-workers will be compared to the experimentally measured wave profiles, thereby validating mechanisms of dislocation generation and motion. Some DD simulation results are presented to demonstrate the feasibility of using a combined experimental/simulation effort for the validation of dislocation generation and mobility physics issues in the phonon drag regime.
Date: February 19, 2004
Creator: Cazamias, J; Lassila, D; Shehadeh, M & Zbib, H
Object Type: Report
System: The UNT Digital Library
A High-Wavenumber Viscosity for High-Resolution Numerical Methods (open access)

A High-Wavenumber Viscosity for High-Resolution Numerical Methods

Numerical simulations of compressible flows are commonly based on the Euler equations when effects of viscosity are thought to be negligible. These equations admit singular solutions, even in cases where the initial and boundary conditions are smooth. So-called ''Euler solvers'' rely on numerical dissipation, explicitly or implicitly present in the scheme, to regularize the problem, such that physical solutions are selected.
Date: February 19, 2003
Creator: Cook, A & Cabot, W H
Object Type: Report
System: The UNT Digital Library
Technical Status Report for US Wind Farmers Network (open access)

Technical Status Report for US Wind Farmers Network

The theme of the work in this quarter was community-based wind and locally owned wind projects. The work Windustry has done is just beginning to touch the heart of the matter for a hugely interested audience of rural landowners and rural communities. We revised and published a Windustry Newsletter on two farmer owned wind projects called Minwind I and Minwind II. This article was largely researched and written last quarter but the principal individuals that organized the wind projects didn't want any more farmers calling them up than they already had, so they urged us to put a hold on the article or not publish it. This presented a unique problem for Windustry. Up to this point, we had not dealt with generating too much attention for a wind energy project. The story of a group of farmers and individuals pooling their resources for two locally owned commercial-scale wind projects is very compelling and the organizers of the projects were getting a great deal of attention from other farmers that want more details on the project. However, the organizers committed a large amount of their own resources toward the set up of this project which took many hours with their …
Date: February 19, 2003
Creator: Daniels, Lisa
Object Type: Report
System: The UNT Digital Library
Structural Analysis of Shipping Casks, Vol. 9. Energy Absorption Capabilities of Plastically Deformed Struts Under Specified Impact Loading Conditions (open access)

Structural Analysis of Shipping Casks, Vol. 9. Energy Absorption Capabilities of Plastically Deformed Struts Under Specified Impact Loading Conditions

The purpose of this investigation was to determine the energy absorption characteristics of plastically deformed inclined struts under impact loading. This information is needed to provide a usable method by which designers and analysts of shipping casks for radioactive or fissile materials can determine the energy absorption capabilities of external longitudinal fins on cylindrical casks under specified impact conditions. A survey of technical literature related to experimental determination of the dynamic plastic behavior of struts revealed no information directly applicable to the immediate problem, especially in the impact velocity ranges desired, and an experimental program was conducted to obtain the needed data. Mild-steel struts with rectangular cross sections were impacted by free-falling weights dropped from known heights. These struts or fin specimens were inclined at five different angles to simulate different angles of impact that fins on a shipping cask could experience under certain accident conditions. The resisting force of the deforming strut was measured and recorded as a function of time by using load cells instrumented with resistance strain gage bridges, signal conditioning equipment, an oscilloscope, and a Polaroid camera. The acceleration of the impacting weight was measured and recorded as a function of time during the latter portion …
Date: February 19, 2001
Creator: Davis, F. C.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
NWChem Meeting on Science Driven Petascale Computing and Capability Development at EMSL (open access)

NWChem Meeting on Science Driven Petascale Computing and Capability Development at EMSL

On January 25, and 26, 2007, an NWChem meeting was held that was attended by 65 scientists from 29 institutions including 22 universities and 5 national laboratories. The goals of the meeting were to look at major scientific challenges that could be addressed by computational modeling in environmental molecular sciences, and to identify the associated capability development needs. In addition, insights were sought into petascale computing developments in computational chemistry. During the meeting common themes were identified that will drive the need for the development of new or improved capabilities in NWChem. Crucial areas of development that the developer's team will be focusing on are (1) modeling of dynamics and kinetics in chemical transformations, (2) modeling of chemistry at interfaces and in the condensed phase, and (3) spanning longer time scales in biological processes modeled with molecular dynamics. Various computational chemistry methodologies were discussed during the meeting, which will provide the basis for the capability developments in the near or long term future of NWChem.
Date: February 19, 2007
Creator: De Jong, Wibe A.
Object Type: Report
System: The UNT Digital Library
Fabrication and applications of large aperture diffractive optics (open access)

Fabrication and applications of large aperture diffractive optics

Large aperture diffractive optics are needed in high power laser applications to protect against laser damage during operation and in space applications to increase the light gathering power and consequently the signal to noise. We describe the facilities we have built for fabricating meter scale diffractive optics and discuss several examples of these.
Date: February 19, 2002
Creator: Dixit, S; Britten, J B; Hyde, R; Rushford, M; Summers, L & Toeppen, J
Object Type: Article
System: The UNT Digital Library
Effect of surface carbon structure on the electrochemical performance of LiFePO{sub 4} (open access)

Effect of surface carbon structure on the electrochemical performance of LiFePO{sub 4}

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Date: February 19, 2003
Creator: Doeff, Marca M.; Hu, Yaoqin; McLarnon, Frank & Kostecki, Robert
Object Type: Article
System: The UNT Digital Library
Armored Enzyme Nanoparticles for Remediation of Subsurface Contaminants (open access)

Armored Enzyme Nanoparticles for Remediation of Subsurface Contaminants

The remediation of subsurface contaminants is a critical problem for the Department of Energy, other government agencies, and our nation. Severe contamination of soil and groundwater exists at several DOE sites due to various methods of intentional and unintentional release. Given the difficulties involved in conventional removal or separation processes, it is vital to develop methods to transform contaminants and contaminated earth/water to reduce risks to human health and the environment. Transformation of the contaminants themselves may involve conversion to other immobile species that do not migrate into well water or surface waters, as is proposed for metals and radionuclides; or degradation to harmless molecules, as is desired for organic contaminants. Transformation of contaminated earth (as opposed to the contaminants themselves) may entail reductions in volume or release of bound contaminants for remediation. Research at Rensselaer focused on the development of haloalkane dehalogenase as a critical enzyme in the dehalogenation of contaminated materials (ultimately trichloroethylene and related pollutants). A combination of bioinformatic investigation and experimental work was performed. The bioinformatics was focused on identifying a range of dehalogenase enzymes that could be obtained from the known proteomes of major microorganisms. This work identified several candidate enzymes that could be obtained …
Date: February 19, 2007
Creator: Dordick, Jonathan S.; Grate, Jay & Kim, Jungbae
Object Type: Report
System: The UNT Digital Library
LLE Review, Quarterly Report: Volume 120, July-September 2009 (open access)

LLE Review, Quarterly Report: Volume 120, July-September 2009

This issue has the following articles: (1) The Omega Laser Facility Users Group Workshop; (2) The Effect of Condensates and Inner Coatings on the Performance of Vacuum Hohlraum Targets; (3) Zirconia-Coated-Carbonyl-Iron-Particle-Based Magnetorheological Fluid for Polishing Optical Glasses and Ceramics; (4) All-Fiber Optical Magnetic Field Sensor Based on Faraday Rotation in Highly Terbium Doped Fiber; (5) Femtosecond Optical Pump-Probe Characterization of High-Pressure-Grown Al{sub 0.86}Ga{sub 0.14}N Single Crystals; (6) LLE's Summer High School Research Program; (7) Laser Facility Report; and (8) National Laser Users Facility and External Users Programs.
Date: February 19, 2001
Creator: Edgell, Dana H.
Object Type: Text
System: The UNT Digital Library
A user manual for GINGER and its post-processor XPLOTGIN (open access)

A user manual for GINGER and its post-processor XPLOTGIN

This is Version 1.3 of the manual for the free-electron laser simulation code GINGER and its post-processor.
Date: February 19, 2002
Creator: Fawley, William M.
Object Type: Report
System: The UNT Digital Library
The Use of Kruskal-Newton Diagrams for Differential Equations (open access)

The Use of Kruskal-Newton Diagrams for Differential Equations

The method of Kruskal-Newton diagrams for the solution of differential equations with boundary layers is shown to provide rapid intuitive understanding of layer scaling and can result in the conceptual simplification of some problems. The method is illustrated using equations arising in the theory of pattern formation and in plasma physics.
Date: February 19, 2008
Creator: Fishaleck, T. & White, R. B.
Object Type: Report
System: The UNT Digital Library
Brood Year 2004: Johnson Creek Chinook Salmon Supplementation Report, June 2004 through March 2006. (open access)

Brood Year 2004: Johnson Creek Chinook Salmon Supplementation Report, June 2004 through March 2006.

The Nez Perce Tribe, through funding provided by the Bonneville Power Administration, has implemented a small scale chinook salmon supplementation program on Johnson Creek, a tributary in the South Fork of the Salmon River, Idaho. The Johnson Creek Artificial Propagation Enhancement project was established to enhance the number of threatened Snake River spring/summer chinook salmon (Oncorhynchus tshawytscha) returning to Johnson Creek to spawn through artificial propagation. This was the sixth season of adult chinook broodstock collection in Johnson Creek following collections in 1998, 2000, 2001, 2002, and 2003. Weir installation was completed on June 21, 2004 with the first chinook captured on June 22, 2004 and the last fish captured on September 6, 2004. The weir was removed on September 18, 2004. A total of 338 adult chinook, including jacks, were captured during the season. Of these, 211 were of natural origin, 111 were hatchery origin Johnson Creek supplementation fish, and 16 were adipose fin clipped fish from other hatchery operations and therefore strays into Johnson Creek. Over the course of the run, 57 natural origin Johnson Creek adult chinook were retained for broodstock, transported to the South Fork Salmon River adult holding and spawning facility and held until spawned. …
Date: February 19, 2009
Creator: Gebhards, John S.; Hill, Robert & Daniel, Mitch
Object Type: Report
System: The UNT Digital Library
Continuum simulation of dislocation dynamics: Predictions for internal friction response (open access)

Continuum simulation of dislocation dynamics: Predictions for internal friction response

The amplitude dependent mechanical loss due to bosing of an idealized Frank-Read Source is studied using both simulation and analytical techniques. Dislocations are modeled within isotropic elasticity theory, and are assumed to be in the over-damped limit.
Date: February 19, 2002
Creator: Greaney, P. Alex; Friedman, Lawrence H. & Chrzan, D.C.
Object Type: Article
System: The UNT Digital Library
Measurement of Gas and Liquid Velocities in an Air-Water Two-Phase Flow using Cross-Correlation of Signals from a Double Senor Hot-Film Probe (open access)

Measurement of Gas and Liquid Velocities in an Air-Water Two-Phase Flow using Cross-Correlation of Signals from a Double Senor Hot-Film Probe

Local gas and liquid velocities are measured by cross-correlating signals from a double sensor hot-film anemometer probe in pure water flow and air water two-phase flow. The gas phase velocity measured in two-phase flow agrees with velocity data obtained using high-speed video to within +/-5%. A turbulent structure, present in the liquid phase, allows a correlation to be taken, which is consistent with the expected velocity profiles in pure liquid flow. This turbulent structure is also present in the liquid phase of a two-phase flow system. Therefore, a similar technique can be applied to measure the local liquid velocity in a two-phase system, when conditions permit.
Date: February 19, 2002
Creator: Gurau, B.; Vassalo, P. & Keller, K.
Object Type: Report
System: The UNT Digital Library
Modeling of the Savannah River Site High Level Waste Evaporator Systems (open access)

Modeling of the Savannah River Site High Level Waste Evaporator Systems

Three evaporators are used to reduce the volume of waste in the waste tank farm at the Savannah River Site (SRS). Evaporators are crucial operation in the SRS waste processing and management system. Using the Aspen Custom Modeler(TM) (ACM) software package marketed by Aspen Technology, Inc., the evaporator dynamic flowsheet models have been constructed to simulate the behavior of the evaporator systems. The evaporator models are used to assist operations and planning. The models account for the basic arrangement and flowpath for the evaporators: (1) Feed system, (2) Concentrate system, (3) Overheads system, and (4) Steam system. This paper provides a detailed description of the model development and presents the result of a typical simulation scenario.
Date: February 19, 2003
Creator: Hang, T.
Object Type: Article
System: The UNT Digital Library
Development of an Initial Simulant for the Idaho Tank Farm Solids (open access)

Development of an Initial Simulant for the Idaho Tank Farm Solids

The goal of this task was to develop the methodology for producing a suitable simulant for waste solids and the fabrication of an initial simulant for use in the demonstrations and testing performed as part of the down-select process for disposition of INTEC tank waste. The analytical results from WM-182 and WM-183 tank samples were used as the basis for this work.
Date: February 19, 2003
Creator: Harbour, J.R.
Object Type: Report
System: The UNT Digital Library
Application of Monte Carlo Methods in Molecular Targeted Radionuclide Therapy (open access)

Application of Monte Carlo Methods in Molecular Targeted Radionuclide Therapy

Targeted radionuclide therapy promises to expand the role of radiation beyond the treatment of localized tumors. This novel form of therapy targets metastatic cancers by combining radioactive isotopes with tumor-seeking molecules such as monoclonal antibodies and custom-designed synthetic agents. Ultimately, like conventional radiotherapy, the effectiveness of targeted radionuclide therapy is limited by the maximum dose that can be given to a critical, normal tissue, such as bone marrow, kidneys, and lungs. Because radionuclide therapy relies on biological delivery of radiation, its optimization and characterization are necessarily different than for conventional radiation therapy. We have initiated the development of a new, Monte Carlo transport-based treatment planning system for molecular targeted radiation therapy as part of the MINERVA treatment planning system. This system calculates patient-specific radiation dose estimates using a set of computed tomography scans to describe the 3D patient anatomy, combined with 2D (planar image) and 3D (SPECT, or single photon emission computed tomography) to describe the time-dependent radiation source. The accuracy of such a dose calculation is limited primarily by the accuracy of the initial radiation source distribution, overlaid on the patient's anatomy. This presentation provides an overview of MINERVA functionality for molecular targeted radiation therapy, and describes early validation …
Date: February 19, 2002
Creator: Hartmann Siantar, C; Descalle, M-A; DeNardo, G L & Nigg, D W
Object Type: Article
System: The UNT Digital Library