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Solid Deuterium-Tritium Surface Roughness In A Beryllium Inertial Confinement Fusion Shell (open access)

Solid Deuterium-Tritium Surface Roughness In A Beryllium Inertial Confinement Fusion Shell

Solid deuterium-tritium (D-T) fuel layers for inertial confinement fusion experiments were formed inside of a 2 mm diameter beryllium shell and were characterized using phase-contrast enhanced x-ray imaging. The solid D-T surface roughness is found to be 0.4 {micro}m for modes 7-128 at 1.5 K below the melting temperature. The layer roughness is found to increase with decreasing temperature, in agreement with previous visible light characterization studies. However, phase-contrast enhanced x-ray imaging provides a more robust surface roughness measurement than visible light methods. The new x-ray imaging results demonstrate clearly that the surface roughness decreases with time for solid D-T layers held at 1.5 K below the melting temperature.
Date: April 19, 2006
Creator: Kozioziemski, B J; Sater, J D; Moody, J D; Montgomery, D S & Gautier, C
Object Type: Article
System: The UNT Digital Library
Phase II Calderon Process to Produce Direct Reduced Iron Research and Development Project Quarterly Report: January-March 2006 (open access)

Phase II Calderon Process to Produce Direct Reduced Iron Research and Development Project Quarterly Report: January-March 2006

This project was initially targeted to the making of coke for blast furnaces by using proprietary technology of Calderon in a phased approach, and Phase I was successfully completed. The project was then re-directed to the making of iron units. In 2000, U.S. Steel teamed up with Calderon for a joint effort to produce directly reduced iron with the potential of converting it into molten iron or steel consistent with the Roadmap recommendations of 1998 prepared by the Steel Industry in cooperation with the Department of Energy by using iron ore concentrate and coal as raw materials, both materials being appreciably lower in cost than using iron pellets, briquettes, sinter and coke.
Date: April 19, 2006
Creator: Calderon, Albert
Object Type: Report
System: The UNT Digital Library
Modeling the impact of sea-spray on particle concentrations in a coastal city (open access)

Modeling the impact of sea-spray on particle concentrations in a coastal city

An atmospheric chemistry-transport model is used to assess the impacts of sea-spray chemistry on the particle composition in and downwind of a coastal city--Vancouver, British Columbia. Reactions in/on sea-spray affect the entire particle ensemble and particularly the size distribution of particle nitrate. Urban air quality, and particularly airborne particles, is a major concern in terms of human health impacts. Sea-spray is known to be a major component of the particle ensemble at coastal sites yet relatively few air quality models include the interaction of gases with sea-spray and the fate of the particles produced. Sea-spray is not an inert addition to the particle ensemble because heterogeneous chemistry in/on sea-spray droplets changes the droplets composition and the particle size distribution, which impacts deposition and the ion balance in different particle size fractions. It is shown that the ISOPART model is capable of simulating gas and particle concentrations in the coastal metropolis of Vancouver and the surrounding valley. It is also demonstrated that to accurately simulate ambient concentrations of particles and reactive/soluble gases in a coastal valley it is absolutely critical to include heterogeneous chemistry in/on sea-spray. Partitioning of total particle-NO{sub 3}{sup -} between sea-spray and NH{sub 4}NO{sub 3} is highly sensitive …
Date: April 19, 2006
Creator: Pryor, S C; Barthelmie, R J; Schoof, J T; Binkowski, F S; Monache, L D & Stull, R B
Object Type: Article
System: The UNT Digital Library
Dynamic Data-Driven Event Reconstruction for Atmospheric Releases (open access)

Dynamic Data-Driven Event Reconstruction for Atmospheric Releases

The role of an event reconstruction capability in a case of an atmospheric release is to characterize the source by answering the critical questions--How much material was released? When? Where? and What are the potential consequences? Accurate estimation of the source term is essential to accurately predict plume dispersion, effectively manage the emergency response, and mitigate consequences in a case of an atmospheric release of hazardous material. We are developing a capability that seamlessly integrates observational data streams with predictive models in order to provide probabilistic estimates of unknown source term parameters consistent with both data and model predictions. Our approach utilizes Bayesian inference with stochastic sampling using Markov Chain and Sequential Monte Carlo methodology. The inverse dispersion problem is reformulated into a solution based on efficient sampling of an ensemble of predictive simulations, guided by statistical comparisons with data. We are developing a flexible and adaptable data-driven event-reconstruction capability for atmospheric releases that provides (1) quantitative probabilistic estimates of the principal source-term parameters (e.g., the time-varying release rate and location); (2) predictions of increasing fidelity as an event progresses and additional data become available; and (3) analysis tools for sensor network design and uncertainty studies. Our computational framework incorporates …
Date: April 19, 2006
Creator: Mirin, A. A. & Kosovic, B.
Object Type: Report
System: The UNT Digital Library
Laser Plasma instability reduction by coherence disruption (open access)

Laser Plasma instability reduction by coherence disruption

The saturation levels of stimulated scattering of intense laser light in plasmas and techniques to reduce these levels are of great interest. A simple model is used to highlight the dependence of the reflectivity on the coherence length for the density fluctuations producing the scattering. Sometimes the coherence lengths can be determined nonlinearly. For NIF hohlraum plasmas, a reduction in the coherence lengths might be engineered in several ways. Finally, electron trapping in ion sound waves is briefly examined as a potentially important effect for the saturation of stimulated Brillouin scattering.
Date: April 19, 2006
Creator: Kruer, W. l.; Amendt, P. A.; Meezan, N. & Suter, L. J.
Object Type: Report
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 37, No. 126, Ed. 1 Wednesday, April 19, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 126, Ed. 1 Wednesday, April 19, 2006

Free weekly newspaper that includes business and classified advertising.
Date: April 19, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
[Email from Catherine A. Murphy to Friends, April 19, 2006] (open access)

[Email from Catherine A. Murphy to Friends, April 19, 2006]

Email from Catherine A. Murphy to her friends advising them of her new contact information.
Date: April 19, 2006
Creator: Murphy, Catherine A.
Object Type: Letter
System: The Portal to Texas History
Mannford Eagle (Mannford, Okla.), Vol. 24, No. 52, Ed. 1 Wednesday, April 19, 2006 (open access)

Mannford Eagle (Mannford, Okla.), Vol. 24, No. 52, Ed. 1 Wednesday, April 19, 2006

Weekly newspaper from Mannford, Oklahoma that includes local, state, and national news along with advertising.
Date: April 19, 2006
Creator: Farley, Tim
Object Type: Newspaper
System: The Gateway to Oklahoma History
Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 9, Ed. 1 Wednesday, April 19, 2006 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 9, Ed. 1 Wednesday, April 19, 2006

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: April 19, 2006
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 90, No. 104, Ed. 1 Wednesday, April 19, 2006 (open access)

North Texas Daily (Denton, Tex.), Vol. 90, No. 104, Ed. 1 Wednesday, April 19, 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 19, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Social Security Disability Insurance (SSDI) and Supplemental Security Income (SSI): The Disability Determination and Appeals Process (open access)

Social Security Disability Insurance (SSDI) and Supplemental Security Income (SSI): The Disability Determination and Appeals Process

None
Date: April 19, 2006
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The Greensheet (Dallas, Tex.), Vol. 30, No. 8, Ed. 1 Wednesday, April 19, 2006 (open access)

The Greensheet (Dallas, Tex.), Vol. 30, No. 8, Ed. 1 Wednesday, April 19, 2006

Free weekly newspaper that includes business and classified advertising.
Date: April 19, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 37, No. 125, Ed. 1 Wednesday, April 19, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 125, Ed. 1 Wednesday, April 19, 2006

Free weekly newspaper that includes business and classified advertising.
Date: April 19, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
U.S. National Science Foundation: An Overview (open access)

U.S. National Science Foundation: An Overview

This report discuses the National Science Foundation (NSF), which provides support for investigator-initiated, merit-reviewed, competitively selected awards, state-of-the-art tools, and instrumentation and facilities. The majority of the research supported by the NSF is conducted at U.S. colleges and universities.
Date: April 19, 2006
Creator: Matthews, Christine M.
Object Type: Report
System: The UNT Digital Library
What product might a renewal of Heavy IonFusion development offerthat competes with methane microbes and hydrogen HTGRs (open access)

What product might a renewal of Heavy IonFusion development offerthat competes with methane microbes and hydrogen HTGRs

In 1994 a Fusion Technology journal publication by Logan, Moir and Hoffman described how exploiting unusually-strong economy-of-scale for large (8 GWe-scale) multi-unit HIF plants sharing a driver and target factory among several low cost molten salt fusion chambers {at} < $40M per 2.4 GW fusion each (Fig. 1), could produce electricity below 3 cts/kWehr, even lower than similar multi-unit fission plants. The fusion electric plant could cost $12.5 B for 7.5 GWe and produce hydrogen fuel by electrolysis at prices competitive with gasoline-powered hybrids getting fuel from oil at $20$/bbl. At $60/bbl oil, the fusion plant can cost $35B and compete {at} 10% APR financing. Given massive and still-increasing world demand for transportation fuel even with oil climbing above $60/bbl, large HIF plants producing both low cost electricity and hydrogen could be more relevant to motivate new R&D funding for HIF development in the next few years. Three major challenges to get there: (1) NIF ignition in indirect drive geometry for liquid chambers, (2) a modular accelerator to enable a one-module IRE < $100 M, (3) compatible HIF target, driver and chamber allowing a small driver {at}< $500 M cost for a >100MWe net power DEMO. This scoping study, at …
Date: April 19, 2006
Creator: Logan, Grant; Lee, Ed; Yu, Simon; Briggs, Dick; Barnard, John; Friedman, Alex et al.
Object Type: Report
System: The UNT Digital Library
Design and Implementation of Ceph: A Scalable Distributed File System (open access)

Design and Implementation of Ceph: A Scalable Distributed File System

File system designers continue to look to new architectures to improve scalability. Object-based storage diverges from server-based (e.g. NFS) and SAN-based storage systems by coupling processors and memory with disk drives, delegating low-level allocation to object storage devices (OSDs) and decoupling I/O (read/write) from metadata (file open/close) operations. Even recent object-based systems inherit decades-old architectural choices going back to early UNIX file systems, however, limiting their ability to effectively scale to hundreds of petabytes. We present Ceph, a distributed file system that provides excellent performance and reliability with unprecedented scalability. Ceph maximizes the separation between data and metadata management by replacing allocation tables with a pseudo-random data distribution function (CRUSH) designed for heterogeneous and dynamic clusters of unreliable OSDs. We leverage OSD intelligence to distribute data replication, failure detection and recovery with semi-autonomous OSDs running a specialized local object storage file system (EBOFS). Finally, Ceph is built around a dynamic distributed metadata management cluster that provides extremely efficient metadata management that seamlessly adapts to a wide range of general purpose and scientific computing file system workloads. We present performance measurements under a variety of workloads that show superior I/O performance and scalable metadata management (more than a quarter million metadata …
Date: April 19, 2006
Creator: Weil, S A; Brandt, S A; Miller, E L; Long, D E & Maltzahn, C
Object Type: Article
System: The UNT Digital Library
Annual Site Environmental Report, 2004 (open access)

Annual Site Environmental Report, 2004

This report provides information about environmental programs during 2004 at the Stanford Linear Accelerator Center (SLAC). Seasonal activities that span calendar years are also included. Production of an annual site environmental report (ASER) is a requirement established by the United States Department of Energy (DOE) for all management and operating (M&O) contractors throughout the DOE complex. SLAC is a federally-funded, research and development center with Stanford University as the M&O contractor. The most noteworthy information in this report is summarized in this section. This summary demonstrates the effective application of SLAC environmental management in meeting the site's integrated safety management system (ISMS) goals. For normal daily activities, all SLAC managers and supervisors are responsible for ensuring that proper procedures are followed so that worker safety and health are protected; the environment is protected; and compliance is ensured. Throughout 2004, SLAC focused on these activities through the SLAC management systems (described in Chapter 3). These systems were also the way SLAC approached implementing ''greening of the government'' initiatives such as Executive Order 13148. The management systems at SLAC are effective, supporting compliance with all relevant statutory and regulatory requirements. There were no reportable releases to the environment from SLAC operations during …
Date: April 19, 2006
Creator: Nuckolls, H.
Object Type: Report
System: The UNT Digital Library
Final Technical Report for the Period September 2002 through September 2005; H2-MHR Pre-Conceptual Design Report: SI-Based Plant; H2-MHR Pre-Conceptual Design Report: HTE-Based Plant (open access)

Final Technical Report for the Period September 2002 through September 2005; H2-MHR Pre-Conceptual Design Report: SI-Based Plant; H2-MHR Pre-Conceptual Design Report: HTE-Based Plant

For electricity and hydrogen production, an advanced reactor technology receiving considerable international interest is a modular, passively-safe version of the high-temperature, gas-cooled reactor, known in the U.S. as the Modular Helium Reactor (MHR), which operates at a power level of 600 MW(t). For electricity production, the MHR operates with an outlet helium temperature of 850 C to drive a direct, Brayton-cycle power-conversion system with a thermal-to-electrical conversion efficiency of 48 percent. This concept is referred to as the Gas Turbine MHR (GT-MHR). For hydrogen production, both electricity and process heat from the MHR are used to produce hydrogen. This concept is referred to as the H2-MHR. This report provides pre-conceptual design descriptions of full-scale, nth-of-a-kind H2 MHR plants based on thermochemical water splitting using the Sulfur-Iodine process and High-Temperature Electrolysis.
Date: April 19, 2006
Creator: Richards, M.; Shenoy, A.; Brown, L.; Buckingham, R.; Harvego, E.; Peddicord, K. et al.
Object Type: Report
System: The UNT Digital Library
DE-FG02-01ER83269 Final Report (open access)

DE-FG02-01ER83269 Final Report

Current and next generation experiments in nuclear and elementary particle physics require detectors with high spatial resolution, fast response, and accurate energy information. Such detectors are required for spectroscopy, and imaging of optical and high-energy photons, charged particles, and neutrons, and are of interest not only in nuclear and high-energy physics, but also in other areas such as medical imaging, diffraction, astronomy, nuclear treaty verification, non-destructive evaluation, and geological exploration.
Date: April 19, 2006
Creator: Shah, Kania
Object Type: Report
System: The UNT Digital Library
Wakefields of Sub-Picosecond Electron Bunches (open access)

Wakefields of Sub-Picosecond Electron Bunches

We discuss wakefields excited by short bunches in accelerators. In particular, we review some of what has been learned in recent years concerning diffraction wakes, roughness impedance, coherent synchrotron radiation wakes, and the resistive wall wake, focusing on analytical solutions where possible. As examples, we apply formulas for these wakes to various parts of the Linac Coherent Light Source (LCLS) project. The longitudinal accelerator structure wake of the SLAC linac is an important ingredient in the LCLS bunch compression process. Of the wakes in the undulator region, the dominant one is the resistive wall wake of the beam pipe.
Date: April 19, 2006
Creator: Bane, Karl L. F.
Object Type: Article
System: The UNT Digital Library
Cooperative Research and Development for Advanced Materials in Advanced Industrial Gas Turbines Final Technical Report (open access)

Cooperative Research and Development for Advanced Materials in Advanced Industrial Gas Turbines Final Technical Report

Evaluation of the performance of innovative thermal barrier coating systems for applications at high temperatures in advanced industrical gas turbines.
Date: April 19, 2006
Creator: Subramanian, Ramesh
Object Type: Report
System: The UNT Digital Library
Attenuation of VHE Gamma Rays by the Milky Way Interstellar Radiation Field (open access)

Attenuation of VHE Gamma Rays by the Milky Way Interstellar Radiation Field

The attenuation of very high energy gamma rays by pair production on the Galactic interstellar radiation field has long been thought of as negligible. However, a new calculation of the interstellar radiation field consistent with multi-wavelength observations by DIRBE and FIRAS indicates that the energy density of the Galactic interstellar radiation field is higher, particularly in the Galactic center, than previously thought. We have made a calculation of the attenuation of very high energy gamma rays in the Galaxy using this new interstellar radiation field which takes into account its nonuniform spatial and angular distributions. We find that the maximum attenuation occurs around 100 TeV at the level of about 25% for sources located at the Galactic center, and is important for both Galactic and extragalactic sources.
Date: April 19, 2006
Creator: Moskalenko, Igor V.; /Stanford U., HEPL; Porter, Troy A.; U., /Louisiana State; Strong, Andrew W. & /Garching, Max Planck Inst., MPE
Object Type: Article
System: The UNT Digital Library
Observation of Decays $B^0\to D_s^{(*)+}\pi^-$ and$B^0\to D_s^{(*)-}K^+$ (open access)

Observation of Decays $B^0\to D_s^{(*)+}\pi^-$ and$B^0\to D_s^{(*)-}K^+$

The authors report the observation of decays B{sup 0} {yields} D{sub s}{sup (*)+} {pi}{sup -} and B{sup 0} {yields} D{sub s}{sup (*)-} K{sup +} in a sample of 230 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} events recorded with the BABAR detector at the PEP-II asymmetric-energy e{sup +}e{sup -} storage ring. They measure the branching fractions {Beta}(B{sup 0} {yields} D{sub s}{sup +}{pi}{sup -}) = (1.3 {+-} 0.3(stat) {+-} 0.2(syst)) x 10{sup -5}, {Beta}(B{sup 0} {yields} D{sub s}{sup -}K{sup +}) = (2.5 {+-} 0.4(stat) {+-} 0.4(syst)) x 10{sup -5}, {Beta}(B{sup 0} {yields} D*{sub s}{sup +} {pi}{sup -}) = (2.8 {+-} 0.6(stat) {+-} 0.5 (syst)) x 10{sup -5}, and {Beta}(B{sup 0} {yields} D*{sub s}{sup -} K{sup +}) = (2.0 {+-} 0.5(stat) {+-} 0.4(syst)) x 10{sup -5}. The significance of the measurements to differ from zero are 5, 9, 6, and 5 standard deviations, respectively.
Date: April 19, 2006
Creator: Aubert, B.
Object Type: Report
System: The UNT Digital Library
Studies of D/sJ(*) Production in B Decays and e+ e- ---> c anti-c Events (open access)

Studies of D/sJ(*) Production in B Decays and e+ e- ---> c anti-c Events

The authors report a study of D*{sub sJ}(2317){sup +} and D{sub sJ}(2460){sup +} meson production in B decays. They observe and measure branching fractions for the decays B{sup +} {yields} D{sub sJ}{sup (*)+} {bar D}{sup (*)0} and B{sup 0} {yields} D{sub sJ}{sup (*)+} {bar D}{sup (*)-} with the subsequent decays D*{sub sJ}(2317){sup +} {yields} D{sub s}{sup +} {pi}{sup 0}, D{sub sJ}(2460){sup +} {yields} D*{sub s}{sup +}{pi}{sup 0}, and D{sub sJ}(2460){sup +} {yields} D{sub s}{sup +}{gamma}. In addition, they perform an angular analysis of D{sub sJ}(2460){sup +} {yields} D{sub s}{sup +}{gamma} decays to test the different D{sub sJ}(2460){sup +} spin hypotheses.
Date: April 19, 2006
Creator: Poireau, V.
Object Type: Article
System: The UNT Digital Library