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IRS Offers in Compromise: Performance Has Been Mixed; Better Management Information and Simplification Could Improve the Program (open access)

IRS Offers in Compromise: Performance Has Been Mixed; Better Management Information and Simplification Could Improve the Program

A letter report issued by the Government Accountability Office with an abstract that begins "Taxpayers unable to fully pay their tax liabilities may apply for an offer in compromise (OIC), an agreement with IRS to pay what they can afford. IRS writes off the rest of the liability. In 2005, IRS accepted over 14,000 offers. Because of concerns about program performance and a new category of offers based on exceptional circumstances, GAO was asked to (1) describe the trends in program's performance and their causes and (2) determine whether IRS's regulations for exceptional circumstance offers are consistent with statute. GAO examined five program objectives: timeliness, quality, accessibility, compliance, and cost."
Date: April 20, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Climate Modeling using High-Performance Computing (open access)

Climate Modeling using High-Performance Computing

The Center for Applied Scientific Computing (CASC) and the LLNL Climate and Carbon Science Group of Energy and Environment (E&E) are working together to improve predictions of future climate by applying the best available computational methods and computer resources to this problem. Over the last decade, researchers at the Lawrence Livermore National Laboratory (LLNL) have developed a number of climate models that provide state-of-the-art simulations on a wide variety of massively parallel computers. We are now developing and applying a second generation of high-performance climate models.
Date: April 20, 2006
Creator: Mirin, A. A. & Wickett, M.
Object Type: Report
System: The UNT Digital Library
Structures in Molecular Clouds: Modeling (open access)

Structures in Molecular Clouds: Modeling

We attempt to predict the observed morphology, column density and velocity gradient of Pillar II of the Eagle Nebula, using Rayleigh Taylor (RT) models in which growth is seeded by an initial perturbation in density or in shape of the illuminated surface, and cometary models in which structure is arises from a initially spherical cloud with a dense core. Attempting to mitigate suppression of RT growth by recombination, we use a large cylindrical model volume containing the illuminating source and the self-consistently evolving ablated outflow and the photon flux field, and use initial clouds with finite lateral extent. An RT model shows no growth, while a cometary model appears to be more successful at reproducing observations.
Date: April 20, 2006
Creator: Kane, J. O.; Mizuta, A.; Pound, M. W.; Remington, B. A. & Ryutov, D. D.
Object Type: Article
System: The UNT Digital Library
Formation of Pillars at the Boundaries between HII Regions and Molecular Clouds (open access)

Formation of Pillars at the Boundaries between HII Regions and Molecular Clouds

We investigate numerically the hydrodynamic instability of an ionization front (IF) accelerating into a molecular cloud, with imposed initial perturbations of different amplitudes. When the initial amplitude is small, the imposed perturbation is completely stabilized and does not grow. When the initial perturbation amplitude is large enough, roughly the ratio of the initial amplitude to wavelength is greater than 0.02, portions of the IF temporarily separate from the molecular cloud surface, locally decreasing the ablation pressure. This causes the appearance of a large, warm HI region and triggers nonlinear dynamics of the IF. The local difference of the ablation pressure and acceleration enhances the appearance and growth of a multimode perturbation. The stabilization usually seen at the IF in the linear regimes does not work due to the mismatch of the modes of the perturbations at the cloud surface and in density in HII region above the cloud surface. Molecular pillars are observed in the late stages of the large amplitude perturbation case. The velocity gradient in the pillars is in reasonably good agreement with that observed in the Eagle Nebula. The initial perturbation is imposed in three different ways: in density, in incident photon number flux, and in the …
Date: April 20, 2006
Creator: Mizuta, A.; Kane, J. O.; Pound, M. W.; Remington, B. A.; Ryutov, D. D. & Takabe, H.
Object Type: Article
System: The UNT Digital Library
Numerical Simulation of a Laboratory-Scale Turbulent SlotFlame (open access)

Numerical Simulation of a Laboratory-Scale Turbulent SlotFlame

We present three-dimensional, time-dependent simulations ofthe flowfield of a laboratory-scale slot burner. The simulations areperformed using an adaptive time-dependent low Mach number combustionalgorithm based on a second-order projection formulation that conservesboth species mass and total enthalpy. The methodology incorporatesdetailed chemical kinetics and a mixture model for differential speciesdiffusion. Methane chemistry and transport are modeled using the DRM-19mechanism along with its associated thermodynamics and transportdatabases. Adaptive mesh refinementdynamically resolves the flame andturbulent structures. Detailedcomparisons with experimental measurementsshow that the computational results provide a good prediction of theflame height, the shape of the time-averaged parabolic flame surfacearea, and the global consumption speed (the volume per second ofreactants consumed divided by the area of the time-averaged flame). Thethickness of the computed flamebrush increases in the streamwisedirection, and the flamesurface density profiles display the same generalshapes as the experiment. The structure of the simulated flame alsomatches the experiment; reaction layers are thin (typically thinner than1 mm) and the wavelengths of large wrinkles are 5--10 mm. Wrinklesamplify to become long fingers of reactants which burn through at a neckregion, forming isolated pockets of reactants. Thus both the simulatedflame and the experiment are in the "corrugated flameletregime."
Date: April 20, 2006
Creator: Bell, John B.; Day, Marcus S.; Grcar, Joseph F.; Lijewski,Michael J.; Driscoll, James F. & Filatyev, Sergei A.
Object Type: Article
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 37, No. 128, Ed. 1 Thursday, April 20, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 128, Ed. 1 Thursday, April 20, 2006

Free weekly newspaper that includes business and classified advertising.
Date: April 20, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 37, No. 129, Ed. 1 Thursday, April 20, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 129, Ed. 1 Thursday, April 20, 2006

Free weekly newspaper that includes business and classified advertising.
Date: April 20, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Port Aransas South Jetty (Port Aransas, Tex.), Vol. 36, No. 16, Ed. 1 Thursday, April 20, 2006 (open access)

Port Aransas South Jetty (Port Aransas, Tex.), Vol. 36, No. 16, Ed. 1 Thursday, April 20, 2006

Weekly newspaper from Port Aransas, Texas on Mustang Island that includes local, state and national news along with extensive advertising.
Date: April 20, 2006
Creator: Judson, Mary Henkel
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 90, No. 105, Ed. 1 Thursday, April 20, 2006 (open access)

North Texas Daily (Denton, Tex.), Vol. 90, No. 105, Ed. 1 Thursday, April 20, 2006

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: April 20, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Texas Jewish Post (Fort Worth, Tex.), Vol. 60, No. 16, Ed. 1 Thursday, April 20, 2006 (open access)

Texas Jewish Post (Fort Worth, Tex.), Vol. 60, No. 16, Ed. 1 Thursday, April 20, 2006

Weekly Jewish newspaper from Fort Worth, Texas that includes local, state and national news along with extensive advertising.
Date: April 20, 2006
Creator: Wisch, Rene
Object Type: Newspaper
System: The Portal to Texas History

[North view of the administration building]

Image of the Administration Building from the North. It is framed by clouds and darker clouds make up the backdrop. The pathway leading up to the building is also visible through the trees and students are walking along it. The Information Sciences Building, now Sycamore Hall, is to the left and Kerr Hall and Willis Library are visible behind the Administration Building.
Date: April 20, 2006
Creator: University of North Texas. University Relations, Communications and Marketing.
Object Type: Photograph
System: The UNT Digital Library
The Albany News (Albany, Tex.), Vol. 130, No. 47, Ed. 1 Thursday, April 20, 2006 (open access)

The Albany News (Albany, Tex.), Vol. 130, No. 47, Ed. 1 Thursday, April 20, 2006

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.
Date: April 20, 2006
Creator: Lucas, Melinda L.
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Arlington-Grand Prairie, Tex.), Vol. 30, No. 10, Ed. 1 Thursday, April 20, 2006 (open access)

The Greensheet (Arlington-Grand Prairie, Tex.), Vol. 30, No. 10, Ed. 1 Thursday, April 20, 2006

Free weekly newspaper that includes business and classified advertising.
Date: April 20, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
300 Area D4 Project 1st Quarter Fiscal Year 2006 Building Completion Report (open access)

300 Area D4 Project 1st Quarter Fiscal Year 2006 Building Completion Report

This report documents the deactivation, decontamination, decommissioning, and demolition of the MO-052, 3225, 334, 334A, and 334-TF Buildings in the 300 Area of the Hanford Site. The D4 of these facilities included characterization, engineering, removal of hazardous and radiologically contaminated materials, equipment removal, utility disconnection, deactivation, decontamination, demolition of the structure, and stabilization or removal of the remaining slab and foundation as appropriate.
Date: April 20, 2006
Creator: Smith, David S.
Object Type: Report
System: The UNT Digital Library
Implications of the measurement of the B0s Bbar0s massdifference (open access)

Implications of the measurement of the B0s Bbar0s massdifference

We analyze the significant new model independent constraints on extensions of the standard model (SM) that follow from the recent measurements of the B{sup 0}{sub s} {bar B}{sup 0}{sub s} mass difference. The time-dependent CP asymmetry in B{sub s} {yields} {psi}{phi}, S{sub {psi}{phi}}, will be measured with good precision in the first year of LHC data taking, which will further constrain the parameter space of many extensions of the SM, in particular, next-to-minimal flavor violation. The CP asymmetry in semileptonic B{sub s} decay, A{sup s}{sub SL}, is also important to constrain these frameworks, and could give further clues to our understanding the flavor sector in the LHC era. We point out a strong correlation between S{sub {psi}{phi}} and A{sup s}{sub SL} in a very broad class of new physics models.
Date: April 20, 2006
Creator: Ligeti, Zoltan; Papucci, Michele & Perez, Gilad
Object Type: Article
System: The UNT Digital Library
High Level Waste System Impacts from Acid Dissolution of Sludge (open access)

High Level Waste System Impacts from Acid Dissolution of Sludge

This research evaluates the ability of OLI{copyright} equilibrium based software to forecast Savannah River Site High Level Waste system impacts from oxalic acid dissolution of Tank 1-15 sludge heels. Without further laboratory and field testing, only the use of oxalic acid can be considered plausible to support sludge heel dissolution on multiple tanks. Using OLI{copyright} and available test results, a dissolution model is constructed and validated. Material and energy balances, coupled with the model, identify potential safety concerns. Overpressurization and overheating are shown to be unlikely. Corrosion induced hydrogen could, however, overwhelm the tank ventilation. While pH adjustment can restore the minimal hydrogen generation, resultant precipitates will notably increase the sludge volume. OLI{copyright} is used to develop a flowsheet such that additional sludge vitrification canisters and other negative system impacts are minimized. Sensitivity analyses are used to assess the processability impacts from variations in the sludge/quantities of acids.
Date: April 20, 2006
Creator: KETUSKY, EDWARD
Object Type: Report
System: The UNT Digital Library
The effect of solvent dynamics on the low frequency collectivemotions of DNA in solution and unoriented films (open access)

The effect of solvent dynamics on the low frequency collectivemotions of DNA in solution and unoriented films

Infrared spectroscopy is used to probe the dynamics of invitro samples of DNA prepared as solutions and as solid unoriented films.The lowest frequency DNA mode identified in the far-infrared spectra ofthe DNA samples is found to shift in frequency when the solvent influencein the hydration shell is altered. The lowest frequency mode also hascharacteristics that are similar to beta - relaxations identified inother glass forming polymers.
Date: April 20, 2006
Creator: Woods, K.N.; Lee, S.A.; Holman, H.-Y.N. & Wiedemann, H.
Object Type: Article
System: The UNT Digital Library
Mass-stripping analysis of an interstellar cloud by a supernova shock (open access)

Mass-stripping analysis of an interstellar cloud by a supernova shock

The interaction of supernova shocks and interstellar clouds is an important astrophysical phenomenon since it can result in stellar and planetary formation. Our experiments attempt to simulate this mass-loading as it occurs when a shock passes through interstellar clouds. We drive a strong shock using the Omega laser ({approx} 5 kJ) into a foam-filled cylinder with an embedded Al sphere (diameter D = 120 {micro}m) simulating an interstellar cloud. The density ratio between Al and foam is {approx}9. We have previously reported on the interaction between shock and cloud, the ensuing Kelvin-Helmholtz and Widnall instabilities, and the rapid stripping of all mass from the cloud. We now present a theory that explains the rapid mass-stripping. The theory combines (1) the integral momentum equations for a viscous boundary layer, (2) the equations for a potential flow past a sphere, (3) Spalding's law of the wall for turbulent boundary layers, and (4) the skin friction coefficient for a turbulent boundary layer on a flat plate. The theory gives as its final result the mass stripped from a sphere in a turbulent high Reynolds number flow, and it agrees very well with our experimental observations.
Date: April 20, 2006
Creator: Hansen, J. F.; Robey, H. F.; Miles, A. R.; Klein, R. I. & McKee, C. F.
Object Type: Article
System: The UNT Digital Library
Defining an end state for CO2 sequestration and EOR in North America (open access)

Defining an end state for CO2 sequestration and EOR in North America

CO{sub 2} capture and storage (CCS) presents a challenge to long-range planners, economic interests, regulators, law-makers, and other stakeholders and decision makers. To improve and optimize the use of limited resources and finances, it is important to define an end state for CCS. This ends state should be defined around desired goals and reasonable timelines for execution. While this definition may have substantial technology, policy or economic implications, it need not be prescriptive in terms of technology pathway, policy mechanism, or economic targets. To illustrate these concerns, this paper will present a credible vision of what an end state for North American might look like. From that, examples of key investment and planning decisions are provided to illustrate the value of end-state characterization.
Date: April 20, 2006
Creator: Friedmann, S J
Object Type: Article
System: The UNT Digital Library
Laboratory observation of secondary shock formation ahead of a strongly radiative blast wave (open access)

Laboratory observation of secondary shock formation ahead of a strongly radiative blast wave

We have previously reported the experimental discovery of a second shock forming ahead of a radiative shock propagating in Xe. The initial shock is spherical, radiative, with a high Mach number, and it sends a supersonic radiative heat far ahead of itself. The heat wave rapidly slows to a transonic regime and when its Mach number drops to two with respect to the downstream plasma, the heat wave drives a second shock ahead of itself to satisfy mass and momentum conservation in the heat wave reference frame. We now show experimental data from a range of mixtures of Xe and N{sub 2}, gradually changing the properties of the initial shock and the environment into which the shock moves and radiates (the radiative conductivity and the heat capacity). We have successfully observed second shock formation over the entire range from 100% Xe mass fraction to 100% N{sub 2}. The formation radius of the second shock as a function of Xe mass fraction is consistent with an analytical estimate.
Date: April 20, 2006
Creator: Hansen, J. F.; Edwards, M. J.; Froula, D. H.; Edens, A. D.; Gregori, G. & Ditmire, T. R.
Object Type: Article
System: The UNT Digital Library
High Temperature Membrane & Advanced Cathode Catalyst Development (open access)

High Temperature Membrane & Advanced Cathode Catalyst Development

Current project consisted of three main phases and eighteen milestones. Short description of each phase is given below. Table 1 lists program milestones. Phase 1--High Temperature Membrane and Advanced Catalyst Development. New polymers and advanced cathode catalysts were synthesized. The membranes and the catalysts were characterized and compared against specifications that are based on DOE program requirements. The best-in-class membranes and catalysts were downselected for phase 2. Phase 2--Catalyst Coated Membrane (CCM) Fabrication and Testing. Laboratory scale catalyst coated membranes (CCMs) were fabricated and tested using the down-selected membranes and catalysts. The catalysts and high temperature membrane CCMs were tested and optimized. Phase 3--Multi-cell stack fabrication. Full-size CCMs with the down-selected and optimized high temperature membrane and catalyst were fabricated. The catalyst membrane assemblies were tested in full size cells and multi-cell stack.
Date: April 20, 2006
Creator: Protsailo, Lesia
Object Type: Report
System: The UNT Digital Library
Boiler Materials for Ultrasupercritical Coal Power Plants (open access)

Boiler Materials for Ultrasupercritical Coal Power Plants

The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). A limiting factor in this can be the materials of construction. The project goal is to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi). This goal seems achievable based on a preliminary assessment of material capabilities. The project is further intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of …
Date: April 20, 2006
Creator: Viswanathan, R.; Coleman, K.; Shingledecker, J.; Sarver, J.; Stanko, G.; Borden, M. et al.
Object Type: Report
System: The UNT Digital Library
THRESHOLD RESUMMATION EFFECTS IN THE POLARIZED DRELL-YAN PROCESS AT GSI AND J-PARC. (open access)

THRESHOLD RESUMMATION EFFECTS IN THE POLARIZED DRELL-YAN PROCESS AT GSI AND J-PARC.

We present studies of QCD corrections to dilepton production in transversely polarized pp and {bar p}p scattering. In particular we briefly discuss the effects of NNLL threshold resummation on the rapidity distribution of the lepton pair.
Date: April 20, 2006
Creator: YOKOYA, H. & VOGELSANG, W.
Object Type: Article
System: The UNT Digital Library
Development of High Temperature Membranes and Improved Cathode Catalysts; Project Period January 1, 2002 - December 31, 2005 (open access)

Development of High Temperature Membranes and Improved Cathode Catalysts; Project Period January 1, 2002 - December 31, 2005

Polymer Electrolyte Membranes (PEMs) currently available for fuel cell development work are limited to the temperature range of 60-80°C. For mass commercialization in the transportation arena, three important disadvantages that are linked with the relatively low operating temperature range need to be addressed. These three disadvantages are: (a) sluggish cathode kinetics, (b) CO poisoning at the anode and (c) inefficient thermal characteristics. All three of the above mentioned disadvantages could be solved by increasing the operating temperature range to 100-120°C. To understand the issues associated with high temperature PEMFCs operation, UTCFC has teamed with leading research groups that possess competencies in the field of polymer chemistry. The subcontractors on the program were investigating modified Nafion® and new non-Nafion® based, reinforced and non-reinforced membrane systems. Nafion® based PEMs rely on using high temperature inorganic solid conductor fillers like phosphotungstic acid. Hydrocarbon membrane systems are based on poly (arylene ether sulfone) polymers, PEEK, PAN, etc.
Date: April 20, 2006
Creator: Protsailo, Lesia
Object Type: Report
System: The UNT Digital Library