Fluorescence Rise Time Measurements for High Temperature Fluorescence-Based Thermometry (open access)

Fluorescence Rise Time Measurements for High Temperature Fluorescence-Based Thermometry

Certain ceramic-like phosphor materials exhibit bright fluorescence with a pronounced temperature dependence over a range which spans the cryogenic to 1700 C, depending on the specific phosphor. To measure temperature, a surface, for instance a turbine blade, is coated with the material. An optical system, sometimes including optical fibers, conveys stimulating light and collects the emission for analysis. Either emission intensity or decay time may indicate temperature. Previously fielded tests have involved surfaces such as blades, vanes, pistons, in-take valves, sheets of galvanneal steel, etc. The fluorescent coatings may be applied to small parts via sputtering methods or to large areas by mixture with inorganic binders. Presented here are results characterizing fluorescence rise times as a means of determining temperature from ambient to 700 C for Y{sub 2}O{sub 3}:Eu.
Date: March 24, 2005
Creator: Allison, S.W.
Object Type: Report
System: The UNT Digital Library
TRANSPORTATION CASK RECEIPT AND RETURN FACILITY WORKER DOSE ASSESSMENT (open access)

TRANSPORTATION CASK RECEIPT AND RETURN FACILITY WORKER DOSE ASSESSMENT

The purpose of this design calculation is to estimate radiation doses received by personnel working in the Transportation Cask Receipt and Return Facility (TCRRF) of the repository including the personnel at the security gate and cask staging areas. This calculation is required to support the preclosure safety analysis (PCSA) to ensure that the predicted doses are within the regulatory limits prescribed by the U.S. Nuclear Regulatory Commission (NRC). The Cask Receipt and Return Facility receives NRC licensed transportation casks loaded with spent nuclear fuel (SNF) and high-level radioactive waste (HLW). The TCRRF operation starts with the receipt, inspection, and survey of the casks at the security gate and the staging areas, and proceeds to the process facilities. The transportation casks arrive at the site via rail cars or trucks under the guidance of the national transportation system. This calculation was developed by the Environmental and Nuclear Engineering organization and is intended solely for the use of Design and Engineering in work regarding facility design. Environmental and Nuclear Engineering personnel should be consulted before using this calculation for purposes other than those stated herein or for use by individuals other than authorized personnel in the Environmental and Nuclear Engineering organization.
Date: February 24, 2005
Creator: Arakali, V.
Object Type: Report
System: The UNT Digital Library
Measurement of CP Asymmetries in B0->Ks Pi0 Pi0 Decays (open access)

Measurement of CP Asymmetries in B0->Ks Pi0 Pi0 Decays

The authors present a preliminary measurement of the time-dependent CP asymmetry for the neutral B-meson decay into the CP = +1 final state K{sub S}{sup 0}{pi}{sup 0}{pi}{sup 0}, with K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -} and {pi}{sup 0} {yields} {gamma}{gamma}. They use a sample of approximately 227 million B-meson pairs recorded at the {Upsilon}(4S) resonance by the BABAR detector at the PEP-II B-Factory at SLAC. From a maximum likelihood fit they extract the mixing-induced CP-violation parameter S{sub K{sub S}{sup 0}{pi}{sup 0}{pi}{sup 0}} = 0.84 {+-} 0.71(stat) {+-} 0.08(syst) and the direct CP-violation parameter C{sub K{sub S}{sup 0}}{pi}{sup 0}{pi}{sup 0} = 0.27 {+-} 0.52(stat) {+-} 0.13(syst), where the first uncertainty is statistical and the second systematic.
Date: August 24, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of Time-Dependent CP Asymmetries in B0 to D(*)D Decays (open access)

Measurement of Time-Dependent CP Asymmetries in B0 to D(*)D Decays

The authors present a first measurement of CP asymmetries in neutral B decays to D{sup +}D{sup -}, and updated CP asymmetry measurements in decays to D*{sup +}D{sup -} and D*{sup -}D{sup +}. They use fully-reconstructed decays collected in a data sample of (232 {+-} 3) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} events in the BABAR detector at the PEp-II asymmetric-energy B Factory at SLAC. they determine the time-dependent asymmetry parameters to be S{sub D*{sup +}D{sup -}} = -0.54 {+-} 0.35 {+-} 0.07, C{sub D*{sup +}D{sup -}} = 0.09 {+-} 0.25 {+-} 0.06, S{sub D*{sup -}D{sup +}} = -0.29 {+-} 0.33 {+-} 0.07, C{sub D*{sup -}D{sup +}} = 0.17 {+-} 0.24 {+-} 0.04, S{sub D{sup +}D{sup -}} = -0.29 {+-} 0.63 {+-} 0.06, and C{sub D{sup +}D{sup -}} = 0.11 {+-} 0.35 {+-} 0.06, where in each case the first error is statistical and the second error is systematic.
Date: June 24, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of Time-dependent CP-Violating Asymmetries in B0 --> KsKsKs Decays (open access)

Measurement of Time-dependent CP-Violating Asymmetries in B0 --> KsKsKs Decays

The authors present preliminary measurements of the CP asymmetry parameters in B{sup 0} {yields} K{sub S}{sup 0}K{sub S}{sup 0}K{sub S}{sup 0} decays, reconstructing two of the K{sub S}{sup 0} into {pi}{sup +}{pi}{sup -} and one into {pi}{sup 0}{pi}{sup 0}. In a sample of 227 M B{bar B} pairs collected by the BABAR detector at the PEP-II B Factory at SLAC, they find the CP parameters to be S = -0.25{sub -0.61}{sup +0.68}(stat) {+-} 0.05(syst) and C = 0.56{sub -0.43}{sup +0.34}(stat) {+-} 004(syst). Combining this result with the previous BABAR measurement, obtained from events with three K{sub S}{sup 0} decaying into {pi}{sup +}{pi}{sup -}, they get S = -0.63{sub -0.28}{sup +0.32}(stat) {+-} 0.04(syst); C = -0.10 {+-} 0.25(stat) {+-} 0.05, (syst).
Date: August 24, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
Object Type: Article
System: The UNT Digital Library
Graph-based Techniques for Orbit Classification: Early Results (open access)

Graph-based Techniques for Orbit Classification: Early Results

None
Date: September 24, 2005
Creator: Bagherjeiran, A. & Kamath, C.
Object Type: Report
System: The UNT Digital Library
Fractional-Slot Surface Mounted PM Motors with Concentrated Windings for HEV Traction Drives (open access)

Fractional-Slot Surface Mounted PM Motors with Concentrated Windings for HEV Traction Drives

High-power density and efficiency resulting from elimination of rotor windings and reduced magnetic-flux losses have made the rare earth permanent magnet (PM) motor a leading candidate for the Department of Energy's Office of FreedomCAR and Vehicle Technologies (FCVTs) traction drive motor. These traction drives are generally powered by radial-gap motors, having the magnets on or embedded in a rotating cylinder separated from the inside surface of a slotted cylindrical stator by an annular gap. The two main types of radial-gap PM rotors are those with magnets mounted on the surface of a supporting back iron, called PM surface mounted (PMSM) motors, and those with magnets mounted in slots in the rotor, called interior PM (IPM) motors. Most early PM motor research was on the PMSM motor, which was thought to have an inherently low stator inductance. A low stator inductance can lead to currents dangerously exceeding rated current as the back-emf across the inductance increases with speed; consequently, part of the attempted solution has been to increase the stator inductance to reduce the rate of current rise. Although analysis suggested that there should be no problem designing sufficiently high stator inductance into PMSMs, attempts to do so were often not …
Date: October 24, 2005
Creator: Bailey, J. M. & McKeever, J. W.
Object Type: Report
System: The UNT Digital Library
DNA Sliding Clamps: Just the Right Twist to Load onto DNA (open access)

DNA Sliding Clamps: Just the Right Twist to Load onto DNA

Two recent papers illuminate a long sought step in DNA sliding clamp loading. One paper reveals the structure of the PCNA clamp wrapped around DNA--still open from being loaded--while a second paper discovers that the clamp may assist this process by forming a right-handed helix upon opening.
Date: October 24, 2005
Creator: Barsky, D & Venclovas, C
Object Type: Article
System: The UNT Digital Library
Actinic inspection of multilayer defects on EUV masks (open access)

Actinic inspection of multilayer defects on EUV masks

The production of defect-free mask blanks, and the development of techniques for inspecting and qualifying EUV mask blanks, remains a key challenge for EUV lithography. In order to ensure a reliable supply of defect-free mask blanks, it is necessary to develop techniques to reliably and accurately detect defects on un-patterned mask blanks. These inspection tools must be able to accurately detect all critical defects whilst simultaneously having the minimum possible false-positive detection rate. There continues to be improvement in high-speed non-actinic mask blank inspection tools, and it is anticipated that these tools can and will be used by industry to qualify EUV mask blanks. However, the outstanding question remains one of validating that non-actinic inspection techniques are capable of detecting all printable EUV defects. To qualify the performance of non-actinic inspection tools, a unique dual-mode EUV mask inspection system has been installed at the Advanced Light Source (ALS) synchrotron at Lawrence Berkeley National Laboratory. In high-speed inspection mode, whole mask blanks are scanned for defects using 13.5-nm wavelength light to identify and map all locations on the mask that scatter a significant amount of EUV light. In imaging, or defect review mode, a zone plate is placed in the reflected …
Date: March 24, 2005
Creator: Barty, A.; Liu, Y.; Gullikson, E.; Taylor, J. S. & Wood, O.
Object Type: Article
System: The UNT Digital Library
Measurement of cross sections for the Cu-63(alpha,gamma)Ga-67 reaction from 5.9-8.7 MeV (open access)

Measurement of cross sections for the Cu-63(alpha,gamma)Ga-67 reaction from 5.9-8.7 MeV

None
Date: February 24, 2005
Creator: Basunia, M. S.; Norman, E. B.; Shugart, H. A.; Smith, A. R.; Dolinski, M. J. & Quiter, B. J.
Object Type: Article
System: The UNT Digital Library
The Cooling of a Liquid Absorber using a Small Cooler (open access)

The Cooling of a Liquid Absorber using a Small Cooler

This report discusses the use of small cryogenic coolers for cooling the Muon Ionization Cooling Experiment (MICE) liquid cryogen absorbers. Since the absorber must be able contain liquid helium as well liquid hydrogen, the characteristics of the available 4.2 K coolers are used here. The issues associated with connecting two-stage coolers to liquid absorbers are discussed. The projected heat flows into an absorber and the cool-down of the absorbers using the cooler are presented. The warm-up of the absorber is discussed. Special hydrogen safety issues that may result from the use of a cooler on the absorbers are also discussed.
Date: August 24, 2005
Creator: Baynham, D. E.; Bradshaw, T. W.; Green, M. A.; Ishimoto, S. & Liggins, N.
Object Type: Article
System: The UNT Digital Library
Super symmetry Parameter Analysis with Fittino (open access)

Super symmetry Parameter Analysis with Fittino

We present the results of a realistic global fit of the Lagrangian parameters of the Minimal Supersymmetric Standard Model to simulated data from ILC and LHC with realistic estimates of the observable uncertainties. Higher order radiative corrections are accounted for where ever possible to date. Results are obtained for a modified SPS1a MSSM benchmark scenario but they were checked not to depend critically on this assumption. Exploiting a simulated annealing algorithm, a stable result is obtained without any a priori assumptions on the fit parameters. Most of the Lagrangian parameters can be extracted at the percent level or better if theoretical uncertainties are neglected. Neither LHC nor ILC measurements alone will be sufficient to obtain a stable result. The effects of theoretical uncertainties arising from unknown higher-order corrections and parametric uncertainties are examined qualitatively. They appear to be relevant and the result motivates further precision calculations.
Date: June 24, 2005
Creator: Bechtle, Philip; Desch, Klaus & Wienemann, Peter
Object Type: Article
System: The UNT Digital Library
Estimates and Rigorous Bounds on Pore-Fluid Enhanced Shear Modulus in Poroelastic Media with Hard and Soft Anisotropy (open access)

Estimates and Rigorous Bounds on Pore-Fluid Enhanced Shear Modulus in Poroelastic Media with Hard and Soft Anisotropy

A general analysis of poroelasticity for hexagonal, tetragonal, and cubic symmetry shows that four eigenvectors are pure shear modes with no coupling to the pore-fluid mechanics. The remaining two eigenvectors are linear combinations of pure compression and uniaxial shear, both of which are coupled to the fluid mechanics. The analysis proceeds by first reducing the problem to a 2 x 2 system. The poroelastic system including both anisotropy in the solid elastic frame (i.e., with ''hard anisotropy''), and also anisotropy of the poroelastic coefficients (''soft anisotropy'') is then studied in some detail. In the presence of anisotropy and spatial heterogeneity, mechanics of the pore fluid produces shear dependence on fluid bulk modulus in the overall poroelastic system. This effect is always present (though sometimes small in magnitude) in the systems studied, and can be comparatively large (up to a maximum increase of about 20 per cent) in some porous media--including porous glass and Schuler-Cotton Valley sandstone. General conclusions about poroelastic shear behavior are also related to some recently derived product formulas that determine overall shear response of these systems. Another method is also introduced based on rigorous Hashin-Shtrikman-style bounds for nonporous random polycrystals, followed by related self-consistent estimates of mineral …
Date: January 24, 2005
Creator: Berger, E. L.
Object Type: Article
System: The UNT Digital Library
Fuel Transformer Solid Oxide Fuel Cell Progress Report (open access)

Fuel Transformer Solid Oxide Fuel Cell Progress Report

The following report documents the technical approach and conclusions made by Acumentrics Corporation during latest budget period toward the development of a low cost 10kW tubular SOFC power system. The present program, guided under direction from the National Energy Technology Laboratory of the US DOE, is a nine-year cost shared Cooperative Agreement totaling close to $74M funded both by the US DOE as well as Acumentrics Corporation and its partners. The latest budget period ran from July of 2004 through January 2004. Work was focused on cell technology enhancements as well as BOP and power electronics improvements and overall system design. Significant progress was made in increasing cell power enhancements as well as decreasing material cost in a drive to meet the SECA cost targets. The following report documents these accomplishments in detail as well as the lay out plans for further progress in next budget period.
Date: March 24, 2005
Creator: Bessette, Norman; Schmidt, Douglas S.; Rawson, Jolyon; Allfather, Lars & Litka, Anthony
Object Type: Report
System: The UNT Digital Library
Analyzing Nuclear Fuel Cycles from Isotopic Ratios of Waste Products Applicable to Measurement by Accelerator Mass Spectrometry (open access)

Analyzing Nuclear Fuel Cycles from Isotopic Ratios of Waste Products Applicable to Measurement by Accelerator Mass Spectrometry

An extensive study was conducted to determine isotopic ratios of nuclides in spent fuel that may be utilized to reveal historical characteristics of a nuclear reactor cycle. This forensic information is important to determine the origin of unknown nuclear waste. The distribution of isotopes in waste products provides information about a nuclear fuel cycle, even when the isotopes of uranium and plutonium are removed through chemical processing. Several different reactor cycles of the PWR, BWR, CANDU, and LMFBR were simulated for this work with the ORIGEN-ARP and ORIGEN 2.2 codes. The spent fuel nuclide concentrations of these reactors were analyzed to find the most informative isotopic ratios indicative of irradiation cycle length and reactor design. Special focus was given to long-lived and stable fission products that would be present many years after their creation. For such nuclides, mass spectrometry analysis methods often have better detection limits than classic gamma-ray spectroscopy. The isotopic ratios {sup 151}Sm/{sup 146}Sm, {sup 149}Sm/{sup 146}Sm, and {sup 244}Cm/{sup 246}Cm were found to be good indicators of fuel cycle length and are well suited for analysis by accelerator mass spectroscopy.
Date: August 24, 2005
Creator: Biegalski, S R; Whitney, S M & Buchholz, B
Object Type: Article
System: The UNT Digital Library
The development of a ductility-based aging model for low temperature aged U-6Nb alloy (open access)

The development of a ductility-based aging model for low temperature aged U-6Nb alloy

This study focuses on the ductility evaluation of low-temperature (100 and 200 C) aged U-6Nb alloy. The objective is to develop a ductility-based aging model to improve lifetime prediction for weapon components in the stockpile environment. Literature review shows that the work hardening n-value and the strain-rate hardening mvalue are the two most important metallurgical factors for the uniform and the post-uniform (necking) ductility control, respectively. Unfortunately, both n and m values of the U-6Nb alloy are lacking. The study shows that the total ductility of U-6Nb is dominated by the uniform ductility, which deteriorates in both 100 C and 200 C aging. Further analysis shows that the uniform ductility correlates well with the work hardening n-value of the later stage deformation in which dislocation-slip is the mechanism. The kinetics of the loss of uniform ductility and the associated reduction in work-hardening n-value in low temperature aging will be used for the development of a ductility-based aging model. The necking ductility appears to be a minor but significant factor in the total ductility of U-6Nb. It does not show a clear trend due to large data scatter. The uncertain nature of necking failure may always hinder a reliable measurement of …
Date: March 24, 2005
Creator: Bridges, B
Object Type: Article
System: The UNT Digital Library
Energy-dependent excitation cross section measurements of the diagnostic lines of Fe XVII (open access)

Energy-dependent excitation cross section measurements of the diagnostic lines of Fe XVII

By implementing a large-area, gain-stabilized microcalorimeter array on an electron beam ion trap, the electron-impact excitation cross sections for the dominant x-ray lines in the Fe XVII spectrum have been measured as a function of electron energy up to greater than three times the threshold energy, establishing a benchmark for atomic calculations. The results reveal a consistent overestimation by recent calculations of the excitation cross section of the resonance transition, which is shown to be at the root of several long-standing problems associated with modeling solar and astrophysical Fe XVII spectra. The data do not show strong contributions from resonance excitation contrary to recent statements in the literature.
Date: January 24, 2005
Creator: Brown, G V; Beiersdorfer, P; Chen, H; Scofield, J H; Boyce, K R; Kelley, R L et al.
Object Type: Article
System: The UNT Digital Library
Detailed Numerical Simulation of the Graniteville Train Collision (open access)

Detailed Numerical Simulation of the Graniteville Train Collision

An unfortunate accident occurred in Graniteville, South Carolina on 6 January, 2005 when a train carrying a variety of hazardous chemicals collided with a stationary train parked on a siding rail (spur). The Savannah River National Laboratory (SRNL) runs prognostic atmospheric simulations of the Central Savannah River Area (CSRA) on an operational basis in the event of such airborne releases. Although forecast information was provided at 2-km horizontal grid spacing during the accident response, a higher-resolution simulation was later performed to examine influences of local topography on plume migration. The Regional Atmospheric Modeling System (RAMS, version 4.3.0) was used to simulate meteorology using multiple grids with an innermost grid spacing of 125 meters. This report discusses comparisons of simulated meteorology with local observations and applications using two separate transport models. Results from the simulations are shown to generally agree with meteorological observations at the time. Use of a dense gas model to simulate localized effects indicates agreement with fatalities in the immediate area and visible damage to vegetation.
Date: October 24, 2005
Creator: Buckley, R. L.
Object Type: Article
System: The UNT Digital Library
Savannah River National Laboratory Involvement in the European ENSEMBLE Program (open access)

Savannah River National Laboratory Involvement in the European ENSEMBLE Program

Many atmospheric transport and dispersion models now exist to provide consequence assessment during emergency response to near-field releases. One way of estimating the uncertainty for a given forecast is to statistically analyze an ensemble of results from several models. ENSEMBLE is a European Union program that utilizes an internet-based system to ingest transport results from numerous modeling agencies. This paper addresses the involvement of the Savannah River National Laboratory (SRNL) in ENSEMBLE, and the resulting improvements in SRNL modeling capabilities. SRNL, the only United States agency involved in the ENSEMBLE program, uses a prognostic atmospheric numerical model (the Regional Atmospheric Modeling System, RAMS) to provide three-dimensional and time-varying meteorology as input to a stochastic Lagrangian particle mode . The model design used by SRNL is discussed, including recent upgrades to the system using parallel processing which allows for finer grid resolution in the generation of the meteorology.
Date: October 24, 2005
Creator: Buckley, R. L. & Addies, Robert P.
Object Type: Article
System: The UNT Digital Library
Recent Improvements to an Advanced Atmospheric Transport Modeling System (open access)

Recent Improvements to an Advanced Atmospheric Transport Modeling System

The Atmospheric Technologies Group (ATG) has developed an advanced atmospheric modeling capability using the Regional Atmospheric Modeling System (RAMS) and a stochastic Lagrangian particle dispersion model (LPDM) for operational use at the Savannah River Site (SRS). For local simulations concerning releases from the Central Savannah River Area (CSRA), RAMS is run in a nested grid configuration with horizontal grid spacing of 8 and 2 km for each grid, with 6-hr forecasts updated every 3 hours. An interface to allow for easy user access to LPDM had been generated, complete with post-processing results depicting surface concentration, deposition, and a variety of dose quantities. A prior weakness in this approach was that observations from the SRS tower network were only incorporated into the three-dimensional modeling effort during the initialization process. Thus, if the forecasted wind fields were in error, the resulting plume predictions would also be erroneous. To overcome this shortcoming, the procedure for generating RAMS wind fields and reading them into LPDM has been modified such that SRS wind measurements are blended with the predicted three-dimensional wind fields from RAMS using the Barnes technique. In particular, the horizontal components in RAMS are replaced with the observed values at a series of …
Date: October 24, 2005
Creator: Buckley, R. L. & Hunter, C. H.
Object Type: Article
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, Alabama). 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{reg_sign}) baghouse to collect fly ash. The majority of the fly ash is collected in the ESP with the residual being collected in the COHPAC{reg_sign} baghouse. Activated carbon was injected between the ESP and COHPAC{reg_sign} units to collect the mercury. Short-term mercury removal …
Date: October 24, 2005
Creator: Bustard, Jean; Lindsey, Charles; Brignac, Paul; Starns, Travis; Sjostrom, Sharon & Larson, Cindy
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, Alabama). 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{reg_sign}) baghouse to collect fly ash. The majority of the fly ash is collected in the ESP with the residual being collected in the COHPAC{reg_sign} baghouse. Activated carbon was injected between the ESP and COHPAC{reg_sign} units to collect the mercury. Short-term mercury removal …
Date: January 24, 2005
Creator: Bustard, Jean; Lindsey, Charles; Brignac, Paul; Starns, Travis; Sjostrom, Sharon; Taylor, Trent et al.
Object Type: Report
System: The UNT Digital Library
REVIEW OF FAST FLUX TEST FACILITY (FFTF) FUEL EXPERIMENTS FOR STORAGE IN INTERIM STORAGE CASKS (ISC) (open access)

REVIEW OF FAST FLUX TEST FACILITY (FFTF) FUEL EXPERIMENTS FOR STORAGE IN INTERIM STORAGE CASKS (ISC)

Appendix H, Section H.3.3.10.11 of the Final Safety Analysis Report (FSAR), provides the limits to be observed for fueled components authorized for storage in the Fast Flux Test Facility (FFTF) spent fuel storage system. Currently, the authorization basis allows standard driver fuel assemblies (DFA), as described in the FSAR Chapter 17, Section 17.5.3.1, to be stored provided decay power per assembly is {le} 250 watts, post-irradiation time is four years minimum, average assembly burn-up is 150,000 MWD/MTHM maximum and the pre-irradiation enrichment is 29.3% maximum (per H.3.3.10.11). In addition, driver evaluation (DE), core characterizer assemblies (CCA), and run-to-cladding-breach (RTCB) assemblies are included based on their similarities to a standard DFA. Ident-69 pin containers with fuel pins from these DFAs can also be stored. Section H.3.3.10.11 states that fuel types outside the specification criteria above will be addressed on a case-by-case basis. There are many different types of fuel and blanket experiments that were irradiated in the FFTF which now require offload to the spent fuel storage system. Two reviews were completed for a portion of these special type fuel components to determine if placement into the Core Component Container (CCC)/Interim Storage Cask (ISC) would require any special considerations or changes …
Date: October 24, 2005
Creator: CHASTAIN, S.A.
Object Type: Report
System: The UNT Digital Library
The Limits of Quintessence (open access)

The Limits of Quintessence

We present evidence that the simplest particle-physics scalar-field models of dynamical dark energy can be separated into distinct behaviors based on the acceleration or deceleration of the field as it evolves down its potential towards a zero minimum. We show that these models occupy narrow regions in the phase-plane of w and w', the dark energy equation-of-state and its time-derivative in units of the Hubble time. Restricting an energy scale of the dark energy microphysics limits how closely a scalar field can resemble a cosmological constant. These results, indicating a desired measurement resolution of order \sigma(w')\approx (1+w), define firm targets for observational tests of the physics of dark energy.
Date: May 24, 2005
Creator: Caldwell, R.R. & Linder, Eric V.
Object Type: Article
System: The UNT Digital Library