CT Scans of NASA BSTRA Balls 5f5, f2, f3, sr2c, nb2a, hb2b (open access)

CT Scans of NASA BSTRA Balls 5f5, f2, f3, sr2c, nb2a, hb2b

At the request of Jose Hernandez we performed some feasibility DR/CT scanning of BSTRA Balls of different sizes. To this point we have scanned all the specimens on a single system, HECAT. This particular system employs a 9 meV LINAC as the x-ray source and a THALES 12 x 16 inch 14-bit Amorphous Silicon panel as the detector. In this report we describe the system, detail some of its properties, describe the scans performed and present the data. Figure 1 contains a couple of images of the system as fielded in the 9 MeV bay. The LINAC is in the right portion of the picture. The black panels in the blue frame constitute the High Energy collimator developed specifically for High Energy DR/CT scanning (known here as Stonehenge II). The holes in the collimator panels are beveled to match the distribution of the x-rays from the LINAC, and are sized to just subtend the active area of the THALES Amorphous Silicon panel. Consequently the source to detector distance is restricted to a few positions. Nominally our source to detector distance is 6 meters. The part manipulator, part holder fixturing consists of a translate-rotate assembly on a NEWPORT air bearing table. …
Date: January 29, 2004
Creator: Gross, J; Thompson, R; Perry, R & Schneberk, D
Object Type: Report
System: The UNT Digital Library
FIELD TEST PROGRAM FOR LONG-TERM OPERATION OF A COHPAC SYSTEM FOR REMOVING MERCURY FROM COAL-FIRED FLUE GAS (open access)

FIELD TEST PROGRAM FOR LONG-TERM OPERATION OF A COHPAC SYSTEM FOR REMOVING MERCURY FROM COAL-FIRED FLUE GAS

With the Nation's coal-burning utilities facing the possibility of tighter controls on mercury pollutants, the U.S. Department of Energy is funding projects that could offer power plant operators better ways to reduce these emissions at much lower costs. Sorbent injection technology represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. It involves injecting a solid material such as powdered activated carbon into the flue gas. The gas-phase mercury in the flue gas contacts the sorbent and attaches to its surface. The sorbent with the mercury attached is then collected by the existing particle control device along with the other solid material, primarily fly ash. During 2001, ADA Environmental Solutions (ADA-ES) conducted a full-scale demonstration of sorbent-based mercury control technology at the Alabama Power E.C. Gaston Station (Wilsonville, AL). This unit burns a low-sulfur bituminous coal and uses a hot-side electrostatic precipitator (ESP) in combination with a Compact Hybrid Particulate Collector (COHPAC{trademark}) baghouse to collect fly ash. The majority of the fly ash is collected in the ESP with the residual being collected in the COHPAC{trademark} baghouse. Activated carbon was injected between the ESP and COHPAC{trademark} units to collect the mercury. Short-term mercury removal …
Date: January 29, 2004
Creator: Bustard, Jean; Lindsey, Charles; Brignac, Paul; Starns, Travis; Sjostrom, Sharon; Taylor, Trent et al.
Object Type: Report
System: The UNT Digital Library
GaInAsSb/AlGaAsSb/GaSb Thermophotovoltaic Devices (open access)

GaInAsSb/AlGaAsSb/GaSb Thermophotovoltaic Devices

None
Date: January 29, 2004
Creator: Wang, C. A.
Object Type: Report
System: The UNT Digital Library
IMPROVED IRON CATALYSTS FOR SLURRY PHASE FISCHER-TROPSCH SYNTHESIS (open access)

IMPROVED IRON CATALYSTS FOR SLURRY PHASE FISCHER-TROPSCH SYNTHESIS

None
Date: January 29, 2004
Creator: Bukur, Dragomir B.; Carreto-Vazquez, Victor & Ma, Wen-Ping
Object Type: Report
System: The UNT Digital Library
In situ freeze-capturing of fracture water using cryogenic coring (open access)

In situ freeze-capturing of fracture water using cryogenic coring

Current methods do not allow for sampling of in situ water from unsaturated fractures in low-moisture environments. A novel cryogenic coring technique based on the method developed by Simon and Cooper (1996) is used to collect in situ water in unsaturated fractures. This method uses liquid nitrogen as the drilling fluid, which can freeze the fracture water in place while coring. Laboratory experiments are conducted to demonstrate that water in an unsaturated fracture can be frozen and collected using cryogenic coring.
Date: January 29, 2004
Creator: Su, Grace W.; Wang, Joseph S.Y. & Zacny, Kris
Object Type: Article
System: The UNT Digital Library
Modification to the Monte N-Particle (MCNP) Visual Editor (MCNPVised) to read in Computer Aided Design (CAD) files (open access)

Modification to the Monte N-Particle (MCNP) Visual Editor (MCNPVised) to read in Computer Aided Design (CAD) files

Monte Carlo N-Particle Transport Code (MCNP) (Reference 1) is the code of choice for doing complex neutron/photon/electron transport calculations for the nuclear industry and research institutions. The Visual Editor for Monte Carlo N-Particle (References 2 to 11) is recognized internationally as the best code for visually creating and graphically displaying input files for MCNP. The work performed in this grant enhanced the capabilities of the MCNP Visual Editor to allow it to read in a 2D Computer Aided Design (CAD) file, allowing the user to modify and view the 2D CAD file and then electronically generate a valid MCNP input geometry with a user specified axial extent.
Date: January 29, 2004
Creator: Schwarz, Randy A. Carter, Leeland L.
Object Type: Report
System: The UNT Digital Library
Mono and Multivalency In Tethered Protein-Carbohydrate Bonds (open access)

Mono and Multivalency In Tethered Protein-Carbohydrate Bonds

Molecular recognition in biological systems typically involves large numbers of interactions simultaneously. By using a multivalent approach, weak interactions with fairly low specificity can become strong highly specific interactions. Additionally, this allows an organism to control the strength and specificity of an interaction simply by controlling the number of binding molecules (or binding sites), which in turn can be controlled through transcriptional regulation.
Date: January 29, 2004
Creator: Ratto, T V; Langry, K C; Rudd, R E; Balhorn, R L & McElfresh, M W
Object Type: Article
System: The UNT Digital Library
Paul Trap Simulator Experiment to Model Intense Beam Propagation in Alternating-gradient Transport Systems (open access)

Paul Trap Simulator Experiment to Model Intense Beam Propagation in Alternating-gradient Transport Systems

The results presented here demonstrate that the Paul Trap Simulator Experiment (PTSX) simulates the propagation of intense charged particle beams over distances of many kilometers through magnetic alternating-gradient (AG) transport systems by making use of the similarity between the transverse dynamics of particles in the two systems. Plasmas have been trapped that correspond to normalized intensity parameters s = wp2 (0)/2wq2 * 0.8, where wp(r) is the plasmas frequency and wq is the average transverse focusing frequency in the smooth-focusing approximation. The measured root-mean-squared (RMS) radius of the beam is consistent with a model, equally applicable to both PTSX and AG systems that balances the average inward confining force against the outward pressure-gradient and space-charge forces. The PTSX device confines one-component cesium ion plasmas for hundreds of milliseconds, which is equivalent to over 10 km of beam propagation.
Date: January 29, 2004
Creator: Gilson, Erik P.; Davidson, Ronald C.; Efthimion, Philip C. & Majeski, Richard
Object Type: Report
System: The UNT Digital Library
Progress Report FY04 Quarter 1 (open access)

Progress Report FY04 Quarter 1

In this quarter, a simulation has been carried out to validate the FEM model for a production facility mill configuration, focusing on the shape change evolution of the slab. Results of ingot shape evolution for a 13 pass rolling simulation are given in Figure 1. It was observed that the rollover of the slab is strongly dependent on friction. More studies on friction laws may be necessary for more accurate prediction. Another important feature is the mesh dependence of the result. More frequent remeshing may be necessary to be able to capture the deformation behavior more accurately. These issues are currently being investigated. Also, we expect that ATC will provide the refined fracture model to LLNL shortly. Once available, appropriate modifications will be made in the FEM subroutines, and the validation process for slab fracture will continue.
Date: January 29, 2004
Creator: Couch, R G & Wang, P
Object Type: Report
System: The UNT Digital Library
RP-5 Renewable Energy Efficiency Project (open access)

RP-5 Renewable Energy Efficiency Project

This is the sixth quarterly technical report for the RP-5 Renewable Energy Efficiency Project. The report summarizes the work progress, effort and activities that took place during the period from October 1, 2003 through December 31, 2003. The report has been prepared in accordance with the Department of Energy (DOE) Guidelines. In coordination with the DOE, IEUA has revised the original Cooperative Agreement to reflect the actual and current project scope of work. The original Agreement statement of work (SOW) included conceptual and preliminary equipment and systems, which were further evaluated for feasibility and suitability for the project. As a result, some of the equipment was taken out of the project scope. In response to questions from the DOE, IEUA has submitted a summary report on the Organic Rankine Cycle (ORC) secondary power generation units for availability and suitability for this project and associated safety concerns pointed out by the DOE. IEUA has awarded the consulting engineering contract to Parsons Water and Infrastructure, Inc. to provide the project's design and construction services. The project's pre-design kickoff meeting was held at IEUA's headquarters on December 11, 2003. IEUA has submitted a proposal for a grant offered by California Energy Commission (CEC) …
Date: January 29, 2004
Creator: Clifton, Neil; Whitman, Eliza Jane & Zughbi, Jamal A.
Object Type: Report
System: The UNT Digital Library
Subextensive Scaling in the Athermal, Quasistatic Limit of Amorphous Matter in Plastic Shear Flow (open access)

Subextensive Scaling in the Athermal, Quasistatic Limit of Amorphous Matter in Plastic Shear Flow

We present the results of numerical simulations of an atomistic system undergoing plastic shear flow in the athermal, quasistatic limit. The system is shown to undergo cascades of local re-arrangements, associated with quadrupolar energy fluctuations, which induce system-spanning events organized into lines of slip oriented along the Bravais axes of the simulation cell. A finite size scaling analysis reveals subextensive scaling of the energy drops and participation numbers, linear in the length of the simulation cell, in good agreement with the real-space structure of plastic events
Date: January 29, 2004
Creator: Maloney, C & Lemaitre, A
Object Type: Article
System: The UNT Digital Library
Oleds for General Lighting (open access)

Oleds for General Lighting

The goal of this program was to reduce the long term technical risks that were keeping the lighting industry from embracing and developing organic light-emitting diode (OLED) technology for general illumination. The specific goal was to develop OLEDs for lighting to the point where it was possible to demonstrate a large area white light panel with brightness and light quality comparable to a fluorescence source and with an efficacy comparable to that of an incandescent source. it was recognized that achieving this would require significant advances in three area: (1) the improvement of white light quality for illumination, (2) the improvement of OLED energy efficiency at high brightness, and (3) the development of cost-effective large area fabrication techniques. The program was organized such that, each year, a ''deliverable'' device would be fabricated which demonstrated progress in one or more of the three critical research areas. In the first year (2001), effort concentrated on developing an OLED capable of generating high illumination-quality white light. Ultimately, a down-conversion method where a blue OLED was coupled with various down-conversion layers was chosen. Various color and scattering models were developed to aid in material development and device optimization. The first year utilized this approach …
Date: February 29, 2004
Creator: Duggal, Anil; Foust, Don; Heller, Chris; Nealon, Bill; Turner, Larry; Shiang, Joe et al.
Object Type: Report
System: The UNT Digital Library
Radon Reduction Experience at a Former Uranium Processing Facility (open access)

Radon Reduction Experience at a Former Uranium Processing Facility

Approximately 6,200 cubic meters of waste containing about 2.0E8 MBq of radium-226 are stored in two large silos at the Fernald Site in southwest Ohio. The material is scheduled for retrieval, packaging, off site shipment and disposal by burial. Air in the silos above the stored material contained radon-222 at a concentration of 7.4 E5 Bq/L. Short-lived daughters formed by decay in these headspaces generated dose rates at contact with the top of the silos up to 1.05 mSv/hr and there complicate the process of retrieval. A Radon Control System (RCS) employing carbon adsorption beds has been designed under contract with the Fluor Fernald to remove most of the radon in the headspaces and maintain lower concentrations during periods when work on or above the domes is needed. Removing the radon also removes the short-lived daughters and reduces the dose rate near the domes to 20 to 30 {mu}Sv/hr. Failing to remove the radon would be costly, in the exposure of personnel needed to work extended periods at these moderate dose rates, or in dollars for the application of remote retrieval techniques. In addition, the RCS minimizes the potential for environmental releases. This paper describes the RCS, its mode of …
Date: February 29, 2004
Creator: Eger, K. J.; Rutherford, L.; Rickett, K.; Fellman, R. & Hungate, S.
Object Type: Article
System: The UNT Digital Library
Toxicological Evaluation of Realistic Emissions of Source Aerosols (TERESA): Application to Power Plant-Derived PM2.5 (open access)

Toxicological Evaluation of Realistic Emissions of Source Aerosols (TERESA): Application to Power Plant-Derived PM2.5

This report documents progress made on the subject project during the period of September 1, 2003 through February 28, 2004. The TERESA Study is designed to investigate the role played by specific emissions sources and components in the induction of adverse health effects by examining the relative toxicity of coal combustion and mobile source (gasoline and/or diesel engine) emissions and their oxidative products. The study involves on-site sampling, dilution, and aging of coal combustion emissions at three coal-fired power plants, as well as mobile source emissions, followed by animal exposures incorporating a number of toxicological endpoints. The DOE-EPRI Cooperative Agreement (henceforth referred to as ''the Agreement'') for which this technical progress report has been prepared covers the analysis and interpretation of the field data collected at the first power plant (located in the Upper Midwest), followed by the performance and analysis of similar field experiments at two additional coal-fired power plants utilizing different coal types and with different plant configurations. Modifications to the original study design, which will improve the atmospheric aging component of the project and ensure that emissions are as realistic as possible, have resulted in project delays, and, at the time of report preparation, fieldwork at the …
Date: February 29, 2004
Creator: Rohr, Annette
Object Type: Report
System: The UNT Digital Library
661L Pre Shot Report (open access)

661L Pre Shot Report

None
Date: March 29, 2004
Creator: Bosson, S. T.
Object Type: Report
System: The UNT Digital Library
ADMP Mixing of Tank 18F: History, Modeling, Testing, and Results (open access)

ADMP Mixing of Tank 18F: History, Modeling, Testing, and Results

Residual radioactive waste was removed from Tank 18F in the F-Area Tank Farm at Savannah River Site (SRS), using the advanced design mixer pump (ADMP). Known as a slurry pump, the ADMP is a 55 foot long pump with an upper motor mounted to a steel super structure, which spans the top of the waste tank. The motor is connected by a long vertical drive shaft to a centrifugal pump, which is submerged in waste near the tank bottom. The pump mixes, or slurries, the waste within the tank so that it may be transferred out of the tank. Tank 18F is a 1.3 million gallon, 85 foot diameter underground waste storage tank, which has no internal components such as cooling coils or structural supports. The tank contained a residual 47,000 gallons of nuclear waste, consisting of a gelatinous radioactive waste known as sludge and particulate zeolite. The prediction of the ADMP success was based on nearly twenty five years of research and the application of that research to slurry pump technology. Many personnel at SRS and Pacific Northwest National Laboratories (PNNL) have significantly contributed to these efforts. This report summarizes that research which is pertinent to the ADMP performance …
Date: March 29, 2004
Creator: LEISHEAR, ROBERTA
Object Type: Article
System: The UNT Digital Library
BuildingPI: A future tool for building life cycle analysis (open access)

BuildingPI: A future tool for building life cycle analysis

Traditionally building simulation models are used at the design phase of a building project. These models are used to optimize various design alternatives, reduce energy consumption and cost. Building performance assessment for the operational phase of a buildings life cycle is sporadic, typically working from historical metered data and focusing on bulk energy assessment. Building Management Systems (BMS) do not explicitly incorporate feedback to the design phase or account for any changes, which have been made to building layout or fabric during construction. This paper discusses a proposal to develop an Industry Foundation Classes (IFC) compliant data visualization tool Building Performance Indicator (BuildingPI) for performance metric and performance effectiveness ratio evaluation.
Date: March 29, 2004
Creator: O'Donnell, James; Morrissey, Elmer; Keane, Marcus & Bazjanac,Vladimir
Object Type: Article
System: The UNT Digital Library
Coupled Vadose Zone and Atmospheric Surface-Layer Transport of CO2 from Geologic Carbon Sequestration Sites (open access)

Coupled Vadose Zone and Atmospheric Surface-Layer Transport of CO2 from Geologic Carbon Sequestration Sites

Geologic carbon dioxide (CO{sub 2}) sequestration is being considered as a way to offset fossil-fuel-related CO{sub 2} emissions to reduce the rate of increase of atmospheric CO{sub 2} concentrations. The accumulation of vast quantities of injected carbon dioxide (CO{sub 2}) in geologic sequestration sites may entail health and environmental risks from potential leakage and seepage of CO{sub 2} into the near-surface environment. We are developing and applying a coupled subsurface and atmospheric surface-layer modeling capability built within the framework of the integral finite difference reservoir simulator TOUGH2. The overall purpose of modeling studies is to predict CO{sub 2} concentration distributions under a variety of seepage scenarios and geologic, hydrologic, and atmospheric conditions. These concentration distributions will provide the basis for determining above-ground and near-surface instrumentation needs for carbon sequestration monitoring and verification, as well as for assessing health, safety, and environmental risks. A key feature of CO{sub 2} is its large density ({rho} = 1.8 kg m{sup -3}) relative to air ({rho} = 1.2 kg m{sup -3}), a property that may allow small leaks to cause concentrations in air above the occupational exposure limit of 4 percent in low-lying and enclosed areas such as valleys and basements where dilution rates …
Date: March 29, 2004
Creator: Oldenburg, Curtis M. & Unger, Andre J. A.
Object Type: Article
System: The UNT Digital Library
Design and Implementation of the Control System for a 2 kHz Rotary Fast Tool Servo (open access)

Design and Implementation of the Control System for a 2 kHz Rotary Fast Tool Servo

This paper presents a summary of the performance of our 2 kHz rotary fast tool servo and an overview of its control systems. We also discuss the loop shaping techniques used to design the power amplifier current control loop and the implementation of that controller in an op-amp circuit. The design and development of the control system involved a long list of items including: current compensation; tool position compensation; notch filter design and phase stabilizing with an additional pole for a plant with an undamped resonance; adding viscous damping to the fast tool servo; voltage budget for driving real and reactive loads; dealing with unwanted oscillators; ground loops; digital-to-analog converter glitches; electrical noise from the spindle motor switching power supply; and filtering the spindle encoder signal to generate smooth tool tip trajectories. Eventually, all of these topics will be discussed in detail in a Ph.D. thesis that will include this work. For the purposes of this paper, rather than present a diluted discussion that attempts to touch on all of these topics, we will focus on the first item with sufficient detail for providing insight into the design process.
Date: March 29, 2004
Creator: Montesanti, R C & Trumper, D L
Object Type: Article
System: The UNT Digital Library
Direct Experimental Evidence of Back-Surface Acceleration from Laser-Irradiated Foils (open access)

Direct Experimental Evidence of Back-Surface Acceleration from Laser-Irradiated Foils

Au foils were irradiated with a 100-TW, 100-fs laser at intensities greater than 10{sup 20} W/cm{sup 2} producing proton beams with a total yield of {approx} 10{sup 11} and maximum proton energy of > 9 MeV. Removing contamination from the back surface of Au foils with an Ar-ion sputter gun reduced the total yield of accelerated protons to less than 1% of the yield observed without removing contamination. Removing contamination the front surface (laser-interaction side) of the target had no observable effect on the proton beam. We present a one-dimensional particle-in-cell simulation that models the experiment. Both experimental and simulation results are consistent with the back-surface acceleration mechanism described in the text.
Date: March 29, 2004
Creator: Allen, Matthew; Patel, Pravesh K.; Mackinnon, Andrew; Price, Dwight; Wilks, Scott & Morse, Edward
Object Type: Article
System: The UNT Digital Library
Disposition of Tank 48H Organics By Fluidized Bed Steam Reforming (FBSR) (U) (open access)

Disposition of Tank 48H Organics By Fluidized Bed Steam Reforming (FBSR) (U)

An In Tank Processing (ITP) technology was developed at the Savannah River Site to remove Cs-137 from high-level waste supernates. During the ITP process monosodium titanate and sodium tetraphenylborate (NaTPB) were added to the salt supernate to adsorb Sr-90/Pu-238 and precipitate Cs-137 as CsTPB, respectively. This process was demonstrated at the SRS in 1983. The demonstration produced 53,000 gallons of 2.5 weight per cent Cs rich precipitate containing TPB, which was later washed and diluted to 250,000 gallons. This material is currently stored in SRS tanks. The washed precipitate was to ultimately be disposed in borosilicate glass in the Defense Waste Processing Facility. Due to safety concerns the ITP process was abandoned in 1998, and new technologies are being researched for Cs-137 removal. In order to make space in the SRS Tank farm, the tank waste must be removed. Therefore, the tank waste must be processed to reduce or eliminate levels of nitrates, nitrites, and sodium tetra phenylborate (NaTPB) in order to reduce impacts of these species before it is vitrified at the DWPF. Fluidized Bed Steam Reforming (FBSR) is being considered as a candidate technology for destroying the nitrates and the NaTPB prior to melting. The purposes of the …
Date: March 29, 2004
Creator: JANTZEN, CAROLM.
Object Type: Report
System: The UNT Digital Library
Elastic Face, An Anatomy-Based Biometrics Beyond Visible Cue (open access)

Elastic Face, An Anatomy-Based Biometrics Beyond Visible Cue

This paper describes a face recognition method that is designed based on the consideration of anatomical and biomechanical characteristics of facial tissues. Elastic strain pattern inferred from face expression can reveal an individual's biometric signature associated with the underlying anatomical structure, and thus has the potential for face recognition. A method based on the continuum mechanics in finite element formulation is employed to compute the strain pattern. Experiments show very promising results. The proposed method is quite different from other face recognition methods and both its advantages and limitations, as well as future research for improvement are discussed.
Date: March 29, 2004
Creator: Tsap, L V; Zhang, Y; Kundu, S J; Goldgof, D B & Sarkar, S
Object Type: Article
System: The UNT Digital Library
Electron-Cloud Effects on Heavy-Ion Beams (open access)

Electron-Cloud Effects on Heavy-Ion Beams

Stray electrons can be introduced in positive-charge accelerators for heavy ion fusion (or other applications) as a result of ionization of ambient gas or gas released from walls due to halo-ion impact, or as a result of secondary-electron emission. We are developing a capability for self-consistent simulation of ion beams with the electron clouds they produce. We report on an ingredient in this capability, the effect of specified electron cloud distributions on the dynamics of a coasting ion beam. We consider here electron distributions with axially varying density, centroid location, or radial shape, and examine both random and sinusoidally varying perturbations. We find that amplitude variations are most effective in spoiling ion beam quality, though for sinusoidal variations which match the natural ion beam centroid oscillation or breathing mode frequencies, the centroid and shape perturbations can also be effective. We identify a possible instability associated with resonance with the beam-envelope ''breathing'' mode. One conclusion from this study is that heavy-ion beams are surprisingly robust to electron clouds, compared to a priori expectations.
Date: March 29, 2004
Creator: Azevedo, T; Friedman, A; Cohen, R & Vay, J
Object Type: Report
System: The UNT Digital Library
Field-Scale Migration of 99Tc and 129I at the Nevada Test Site (open access)

Field-Scale Migration of 99Tc and 129I at the Nevada Test Site

The groundwater at the Nevada Test Site (NTS) contains many long-lived radionuclides, including {sup 99}Tc (technetium) and {sup 129}I (iodine), as a result of 828 underground nuclear weapons tests conducted between 1951 and 1992. We synthesized a body of data collected on the distribution of {sup 99}Tc and {sup 129}I in groundwater to assess their migration at NTS, at field scales over distances of hundreds of meters and for durations up to forty years and under hydrogeologic conditions very similar to the proposed geological repository at Yucca Mountain. The results of our study show that Tc does not necessarily exist as a mobile and conservative species TcO{sub 4}{sup -}, as has been commonly assumed. This conclusion is corroborated by recent in situ redox potential measurements, which show that groundwaters at multiple locations of the NTS are not oxidizing, and mobility of reduced Tc species (TcO{sub 2} {center_dot} nH{sub 2}O) is greatly decreased. Speciation of iodine and its associated reactivity is also complex in the groundwater at the NTS, and its effect on the mobility of iodine should be the subject of future studies.
Date: March 29, 2004
Creator: Hu, Q & Smith, D K
Object Type: Article
System: The UNT Digital Library