LIGNITE FUEL ENHANCEMENT (open access)

LIGNITE FUEL ENHANCEMENT

This 4th quarterly Technical Progress Report for the Lignite Fuel Enhancement Project summarizes activities from April 1st through June 30th of 2005. It also summarizes the subsequent purchasing activity and dryer/process construction.
Date: July 7, 2005
Creator: Bullinger, Charles
Object Type: Report
System: The UNT Digital Library
THE EFFECT OF IONIZING RADIATION ON U6+ -PHASES (open access)

THE EFFECT OF IONIZING RADIATION ON U6+ -PHASES

U{sup 6+}-minerals commonly form during the alteration of uraninite and spent nuclear fuel under oxidizing conditions. By the incorporation of actinides and fissiogenic elements into their structures, U{sup 6+}-minerals may be important in retarding the migration of radionuclides released during corrosion of spent nuclear fuel. Thus, the stability and the structural transformation of the U{sup 6+}-minerals in radiation fields are of great interest.
Date: July 7, 2005
Creator: Utsunomiya, S. & Ewing, R. C.
Object Type: Report
System: The UNT Digital Library
Testing the dynamics of B ->pi pi and constraints onalpha (open access)

Testing the dynamics of B ->pi pi and constraints onalpha

In charmless nonleptonic B decays to {pi}{pi} or {rho}{rho}, the ''color allowed'' and ''color suppressed'' tree amplitudes can be studied in a systematic expansion in {alpha}{sub s}(m{sub b}) and {Lambda}{sub QCD}/m{sub b}. At leading order in this expansion their relative strong phase vanishes. The implications of this prediction are obscured by penguin contributions. They propose to use this prediction to test the relative importance of the various penguin amplitudes using experimental data. The present B {yields} {pi}{pi} data suggest that there are large corrections to the heavy quark limit, which can be due to power corrections to the tree amplitudes, large up-penguin amplitude, or enhanced weak annihilation. Because the penguin contributions are smaller, the heavy quark limit is more consistent with the B {yields} {rho}{rho} data, and its implications may become important for the extraction of {alpha} from this mode in the future.
Date: July 7, 2005
Creator: Grossman, Yuval; Hocker, Andreas; Ligeti, Zoltan & Pirjol, Dan
Object Type: Article
System: The UNT Digital Library
Age Dependency Ratios and Social Security Solvency (open access)

Age Dependency Ratios and Social Security Solvency

As highlighted by the Social Security Administration (SSA), the aging of the (United States) population, hastened by the impending retirement of the huge baby-boom generation, has caused policy-makers to question whether the U.S. Social Security system can meet the demands for retirement benefits in the future. Because the current system largely pays benefits through taxes paid by current workers, the financial health of the system is sensitive to the ratio of dependents to workers—sometimes called the age dependency ratio or support ratio. Trends and projections of dependency ratios, including the relationship between both older (years 65 and older) and younger (under age 20) dependents to the working-age population in the United States are considered in the first section of this demographic report. Next, the United States is compared to nine other nations, including the seven other members of the G8. In the final section, policy implications of the changing dependent-to-worker ratios are considered in the context of pay-as-you-go (paygo) social security systems.
Date: July 7, 2005
Creator: Shrestha, Laura B.
Object Type: Report
System: The UNT Digital Library
CFTC Reauthorization in 2005 (open access)

CFTC Reauthorization in 2005

None
Date: July 7, 2005
Creator: Jickling, Mark
Object Type: Report
System: The UNT Digital Library
Legal Services and Noncustodial Parents Who Owe Child Support (open access)

Legal Services and Noncustodial Parents Who Owe Child Support

This report describes some of the child support issues faced by noncustodial parents and discusses areas in which legal services providers funded by the Legal Services Corporation (LSC) are authorized to support poor noncustodial parents.
Date: July 7, 2005
Creator: Solomon-Fears, Carmen
Object Type: Report
System: The UNT Digital Library
Fabrication Of Graded Germanium-Doped CH Shells (open access)

Fabrication Of Graded Germanium-Doped CH Shells

One of the current capsule designs for achieving ignition on the National Ignition Facility (NIF) is a 2 mm diameter graded Ge-doped CH shell that has a 160 {micro}m thick wall. The Ge doping is not uniform, but rather is in radial steps. This graded Ge-doped design allows rougher surface finish than the original undoped CH design thus has a less stringent new surface standard. We selected quality mandrel mandrels by coating dozens of mandrel batches to {approx}70 {micro}m thickness to amplify sub-micrometer defects on the mandrels and successively removed inferior batches. The Ge-doping layers are made by introducing (CH{sub 3}){sub 4}Ge to the gas stream. The doping concentrations were determined by performing tryout runs and characterized by X-ray fluorescence analyses and quantitative radiograph calculations, with good agreement between the methods being demonstrated. The precise layer thickness and Ge concentrations were determined by a non-destructive quantitative contact radiograph. The as-coated shell has an inner 10 {micro}m undoped CH layer, followed by a 48 {micro}m thick 0.83 at.% Ge-doped CH, 10 {micro}m thick 0.38 at.% Ge-doped CH and then 90 {micro}m of undoped CH. The shell meets nearly all the NIF design thickness specifications and Ge concentrations. The atomic force microscope …
Date: July 7, 2005
Creator: Chen, K. C.; Huang, H.; Nikroo, A.; Letts, S. A. & Cook, R. C.
Object Type: Article
System: The UNT Digital Library
Unreviewed Disposal Question Evaluation: Disposal of 0.2 Curie/gallon MAVRC Project Equipment in Vault 1 (open access)

Unreviewed Disposal Question Evaluation: Disposal of 0.2 Curie/gallon MAVRC Project Equipment in Vault 1

The Saltstone Facility 0.2 Curie/gallon MAVRC (Mixer At Vault Roof Concept) Project will utilize various pieces of process equipment that have not been analyzed from a Performance Assessment perspective for future disposal. The proposed activity will involve the disposal of Saltstone process equipment in an empty Vault 1 cell and encasing the equipment in clean (nonradioactive) grout. An examination of this activity indicates that the disposal of up to 20 pieces of each specified component should not affect the assumptions, results, and conclusions of the approved Performance Assessment (PA) and Special Analyses (SA) for Saltstone, and that the activity is within the bounds of the Disposal Authorization Statement (DAS).
Date: July 7, 2005
Creator: Millings, Margaret R.
Object Type: Report
System: The UNT Digital Library
Fast sparse matrix-vector multiplication by exploiting variable block structure (open access)

Fast sparse matrix-vector multiplication by exploiting variable block structure

We improve the performance of sparse matrix-vector multiply (SpMV) on modern cache-based superscalar machines when the matrix structure consists of multiple, irregularly aligned rectangular blocks. Matrices from finite element modeling applications often have this kind of structure. Our technique splits the matrix, A, into a sum, A{sub 1} + A{sub 2} + ... + A{sub s}, where each term is stored in a new data structure, unaligned block compressed sparse row (UBCSR) format . The classical alternative approach of storing A in a block compressed sparse row (BCSR) format yields limited performance gains because it imposes a particular alignment of the matrix non-zero structure, leading to extra work from explicitly padded zeros. Combining splitting and UBCSR reduces this extra work while retaining the generally lower memory bandwidth requirements and register-level tiling opportunities of BCSR. Using application test matrices, we show empirically that speedups can be as high as 2.1x over not blocking at all, and as high as 1.8x over the standard BCSR implementation used in prior work. When performance does not improve, split UBCSR can still significantly reduce matrix storage. Through extensive experiments, we further show that the empirically optimal number of splittings s and the block size for …
Date: July 7, 2005
Creator: Vuduc, R W & Moon, H
Object Type: Report
System: The UNT Digital Library
U.S. Government Capabilities to Support Analysis of Gamma Ray Data Submitted by Field Elements (open access)

U.S. Government Capabilities to Support Analysis of Gamma Ray Data Submitted by Field Elements

As radiation detection in the interest of national security becomes increasingly commonplace, inevitable questions arise concerning the interpretation of data from handheld radioisotope identifiers (RIIDs). Field elements typically require fast answers to provide an effective defense and to minimize the impact on legitimate movement of people and goods. To support this need, on-call experts at Sandia, Los Alamos, and Lawrence Livermore national laboratories cooperate in resolving radiation alarms rapidly and accurately. We present an overview, describe the work in progress to improve capabilities, and report on some of the lessons learned.
Date: July 7, 2005
Creator: Mercer, D J; Blackadar, J M; Dietrich, D D; Smith, D K; Lasche, G P & Waymire, D R
Object Type: Article
System: The UNT Digital Library
Advanced 0.3-NA EUV lithography capabilities at the ALS (open access)

Advanced 0.3-NA EUV lithography capabilities at the ALS

For volume nanoelectronics production using Extreme ultraviolet (EUV) lithography [1] to become a reality around the year 2011, advanced EUV research tools are required today. Microfield exposure tools have played a vital role in the early development of EUV lithography [2-4] concentrating on numerical apertures (NA) of 0.2 and smaller. Expected to enter production at the 32-nm node with NAs of 0.25, EUV can no longer rely on these early research tools to provide relevant learning. To overcome this problem, a new generation of microfield exposure tools, operating at an NA of 0.3 have been developed [5-8]. Like their predecessors, these tools trade off field size and speed for greatly reduced complexity. One of these tools is implemented at Lawrence Berkeley National Laboratory's Advanced Light Source synchrotron radiation facility. This tool gets around the problem of the intrinsically high coherence of the synchrotron source [9,10] by using an active illuminator scheme [11]. Here we describe recent printing results obtained from the Berkeley EUV exposure tool. Limited by the availability of ultra-high resolution chemically amplified resists, present resolution limits are approximately 32 nm for equal lines and spaces and 27 nm for semi-isolated lines.
Date: July 7, 2005
Creator: Naulleau, Patrick; Anderson, Erik; Dean, Kim; Denham, Paul; Goldberg, Kenneth A.; Hoef, Brian et al.
Object Type: Article
System: The UNT Digital Library
MULTISCALE THERMOHYDROLOGIC MODEL (open access)

MULTISCALE THERMOHYDROLOGIC MODEL

The intended purpose of the multiscale thermohydrologic model (MSTHM) is to predict the possible range of thermal-hydrologic conditions, resulting from uncertainty and variability, in the repository emplacement drifts, including the invert, and in the adjoining host rock for the repository at Yucca Mountain. The goal of the MSTHM is to predict a reasonable range of possible thermal-hydrologic conditions within the emplacement drift. To be reasonable, this range includes the influence of waste-package-to-waste-package heat output variability relevant to the license application design, as well as the influence of uncertainty and variability in the geologic and hydrologic conditions relevant to predicting the thermal-hydrologic response in emplacement drifts. This goal is quite different from the goal of a model to predict a single expected thermal-hydrologic response. As a result, the development and validation of the MSTHM and the associated analyses using this model are focused on the goal of predicting a reasonable range of thermal-hydrologic conditions resulting from parametric uncertainty and waste-package-to-waste-package heat-output variability. Thermal-hydrologic conditions within emplacement drifts depend primarily on thermal-hydrologic conditions in the host rock at the drift wall and on the temperature difference between the drift wall and the drip-shield and waste-package surfaces. Thus, the ability to predict a …
Date: July 7, 2005
Creator: Buscheck, T.
Object Type: Report
System: The UNT Digital Library
Combining a thermal-imaging diagnostic with an existing imaging VISAR diagnostic at the National Ignition Facility (NIF) (open access)

Combining a thermal-imaging diagnostic with an existing imaging VISAR diagnostic at the National Ignition Facility (NIF)

Optical diagnostics are currently being designed to analyze high-energy density physics experiments at the National Ignition Facility (NIF). Two independent line-imaging Velocity Interferometer System for Any Reflector (VISAR) interferometers have been fielded to measure shock velocities, breakout times, and emission of targets having sizes of 1-5 mm. An 8-inch-diameter, fused silica triplet lens collects light at f/3 inside the 30-foot-diameter NIF vacuum chamber. VISAR recordings use a 659.5-nm probe laser. By adding a specially coated beam splitter to the interferometer table, light at wavelengths from 540 to 645 nm is spilt into a thermal-imaging diagnostic. Because fused silica lenses are used in the first triplet relay, the intermediate image planes for different wavelengths separate by considerable distances. A corrector lens on the interferometer table reunites these separated wavelength planes to provide a good image. Thermal imaging collects light at f/5 from a 2-mm object placed at Target Chamber Center (TCC). Streak cameras perform VISAR and thermal-imaging recording. All optical lenses are on kinematic mounts so that pointing accuracy of the optical axis may be checked. Counter-propagating laser beams (orange and red) are used to align both diagnostics. The red alignment laser is selected to be at the 50 percent reflection …
Date: July 7, 2005
Creator: Malone, R.; Celeste, J.; Celliers, P.; Frogget, B.; Guyton, R. L.; Kaufman, M. et al.
Object Type: Article
System: The UNT Digital Library