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0.351 micron Laser Beam propagation in High-temperature Plasmas (open access)

0.351 micron Laser Beam propagation in High-temperature Plasmas

A study of the laser-plasma interaction processes have been performed in plasmas that are created to emulate the plasma conditions in indirect drive inertial confinement fusion targets. The plasma emulator is produced in a gas-filled hohlraum; a blue 351-nm laser beam propagates along the axis of the hohlraum interacting with a high-temperature (T{sub e} = 3.5 keV), dense (n{sub e} = 5 x 10{sup 20}cm{sup -3}), long-scale length (L {approx} 2 mm) plasma. Experiments at these conditions have demonstrated that the interaction beam produces less than 1% total backscatter resulting in transmission greater than 90% for laser intensities less than I < 2 x 10{sup 15} W-cm{sup -2}. The bulk plasma conditions have been independently characterized using Thomson scattering where the peak electron temperatures are shown to scale with the hohlraum heater beam energy in the range from 2 keV to 3.5 keV. This feature has allowed us to determine the thresholds for both backscattering and filamentation instabilities; the former measured with absolutely calibrated full aperture backscatter and near backscatter diagnostics and the latter with a transmitted beam diagnostics. A plasma length scaling is also investigated extending our measurements to 4-mm long high-temperature plasmas. At intensities I < 5 x …
Date: December 10, 2007
Creator: Froula, D.; Divol, L.; Meezan, N.; Ross, J.; Berger, R. L.; Michel, P. et al.
Object Type: Report
System: The UNT Digital Library
900-24 Mock Tensile Tests (open access)

900-24 Mock Tensile Tests

None
Date: December 10, 2007
Creator: Cunningham, B J & Gagliardi, F J
Object Type: Report
System: The UNT Digital Library
2008 Brookhaven National Laboratory Annual Illness and Injury Surveillance Report (open access)

2008 Brookhaven National Laboratory Annual Illness and Injury Surveillance Report

The U.S. Department of Energy’s (DOE) commitment to assuring the health and safety of its workers includes the conduct of epidemiologic surveillance activities that provide an early warning system for health problems among workers. The Illness and Injury Surveillance Program monitors illnesses and health conditions that result in an absence of workdays, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: December 10, 2009
Creator: United States. Department of Energy. Office of Illness and Injury Prevention Programs.
Object Type: Report
System: The UNT Digital Library
81891 - A New Class of Solvents for TRU Dissolution and Separation: Ionic Liquids (open access)

81891 - A New Class of Solvents for TRU Dissolution and Separation: Ionic Liquids

Through the current EMSP funding, solvent extraction technologies based on liquid-liquid partitioning of TRU to an Ionic Liquid phase containing conventional complexants has been shown to be viable. The growing understanding of the role that the different components of an ionic liquid can have on the partitioning mechanism, and on the nature of the subsequent dissolved species indicates strongly that ionic liquids are not necessarily direct replacements for volatile or otherwise hazardous organic solvents. Separations and partitioning can be exceptionally complex with competing solvent extraction, cation, anion and sacrificial ion exchange mechanisms are all important, depending on the selection of components for formation of the ionic liquid phase, and that control of these competing mechanisms can be utilized to provide new, alternative separations schemes.
Date: December 10, 2004
Creator: Rogers, Robin D.
Object Type: Report
System: The UNT Digital Library
Abandoned Mine Waste Working Group report (open access)

Abandoned Mine Waste Working Group report

The Mine Waste Working Group discussed the nature and possible contributions to the solution of this class of waste problem at length. There was a consensus that the mine waste problem presented some fundamental differences from the other classes of waste addresses by the Develop On-Site Innovative Technologies (DOIT) working groups. Contents of this report are: executive summary; stakeholders address the problems; the mine waste program; current technology development programs; problems and issues that need to be addressed; demonstration projects to test solutions; conclusion-next steps; and appendices.
Date: December 10, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Absolute Calibration of Image Plate for electrons at energy between 100 keV and 4 MeV (open access)

Absolute Calibration of Image Plate for electrons at energy between 100 keV and 4 MeV

The authors measured the absolute response of image plate (Fuji BAS SR2040) for electrons at energies between 100 keV to 4 MeV using an electron spectrometer. The electron source was produced from a short pulse laser irradiated on the solid density targets. This paper presents the calibration results of image plate Photon Stimulated Luminescence PSL per electrons at this energy range. The Monte Carlo radiation transport code MCNPX results are also presented for three representative incident angles onto the image plates and corresponding electron energies depositions at these angles. These provide a complete set of tools that allows extraction of the absolute calibration to other spectrometer setting at this electron energy range.
Date: December 10, 2007
Creator: Chen, H; Back, N L; Eder, D C; Ping, Y; Song, P M & Throop, A
Object Type: Article
System: The UNT Digital Library
Achieving high sustained performance in an unstructured mesh CFD application (open access)

Achieving high sustained performance in an unstructured mesh CFD application

This paper highlights a three-year project by an interdisciplinary team on a legacy F77 computational fluid dynamics code, with the aim of demonstrating that implicit unstructured grid simulations can execute at rates not far from those of explicit structured grid codes, provided attention is paid to data motion complexity and the reuse of data positioned at the levels of the memory hierarchy closest to the processor, in addition to traditional operation count complexity. The demonstration code is from NASA and the enabling parallel hardware and (freely available) software toolkit are from DOE, but the resulting methodology should be broadly applicable, and the hardware limitations exposed should allow programmers and vendors of parallel platforms to focus with greater encouragement on sparse codes with indirect addressing. This snapshot of ongoing work shows a performance of 15 microseconds per degree of freedom to steady-state convergence of Euler flow on a mesh with 2.8 million vertices using 3072 dual-processor nodes of ASCI Red, corresponding to a sustained floating-point rate of 0.227 Tflop/s.
Date: December 10, 1999
Creator: Keyes, D E; Anderson, W K; Gropp, W D; Kaushik, D K & Smith, B F
Object Type: Article
System: The UNT Digital Library
ADVANCED WAVEFORM SIMULATION FOR SEISMIC MONITORING EVENTS (open access)

ADVANCED WAVEFORM SIMULATION FOR SEISMIC MONITORING EVENTS

We conduct a detailed test of a recently developed technique, CAPloc, in recovering source parameters from a few stations against results from a large broadband network. The method uses a library of 1D Green’s functions which are broken into segments and matched to waveform observations with adjustable timing shifts. These shifts can be established by calibration against a distribution of well-located earthquake and assembled in tomographic images for predicting various phase-delays. Synthetics generated from 2D cross-sections through these models indicates that 1D synthetic waveforms are sufficient in modeling but simply shifted in time for hard-rock sites. This simplification allows the source inversion for both mechanism and location to be easily obtained by grid search. We test one-station mechanisms for 160 events against the array for both PAS and GSC which have data since 1960. While one station solutions work well (about 90%), joint solutions produce more reliable and defensible results. Inverting for both mechanism and location also works well except for certain difficult paths that cross deep basins or propagate along mountain ridges.
Date: December 10, 2007
Creator: Helmberger, Donald V.; Tromp, Jeroen & Rodgers, Arthur J.
Object Type: Report
System: The UNT Digital Library
ALS superbend magnet performance (open access)

ALS superbend magnet performance

The Lawrence Berkeley National Laboratory has been engaged in the design, construction and testing of four superconducting dipoles (Superbends) that are installed in three arcs of the Advanced Light Source (ALS), with the fourth magnet as a spare. This represents a major upgrade to the ALS providing an enhanced flux and brightness at photon energies above 10 keV. In preparation for installation, an extensive set of tests and measurements have been conducted to characterize the magnetic and cryogenic performance of the Superbends and to fiducialize them for accurate placement in the ALS storage ring. The magnets are currently installed, and the storage ring is undergoing final commissioning. This paper will present the results of magnetic and cryogenic testing.
Date: December 10, 2001
Creator: Marks, Steve; Zbasnik, John; Byrne, Warren; Calais, Dennis; Chin, Michael; DeMarco, Richard et al.
Object Type: Article
System: The UNT Digital Library
Analysis of the Department of Energy's Clinch River Breeder Reactor cost estimate (open access)

Analysis of the Department of Energy's Clinch River Breeder Reactor cost estimate

Much of the current congressional debate about the Clinch River Breeder Reactor (CRBR) centers around the estimated cost of designing, constructing, and operating it for a 5-year demonstration period. The Department of Energy (DOE) recently linked the revenue-generating potential of the CRBR beyond the demonstration period to the justification for continued funding. GAO presents information that points out many uncertainties in DOE's estimates of revenue and cost. GAO believes that because these estimates are based on numerous assumptions and calculations concerning events as far as 37 years in the future, they should be viewed with caution. Changes in the underlying assumptions could produce wide variance in the cost estimates. Further, GAO points out that CRBR is a research and development project and that judging its merits solely on cost and revenue estimates projected far into the future may not be appropriate.
Date: December 10, 1982
Creator: Bowsher, C.A.
Object Type: Report
System: The UNT Digital Library
ARAC system (open access)

ARAC system

In spite of the remarkable safety record of the nuclear industry as a whole, recent public concern over the potential impact of the industry's accelerated growth has prompted ERDA to expand its emergency response procedures. The Atmospheric Release Advisory Capability, ARAC, is a computer communications system designed to enhance the existing emergency response capability of ERDA nuclear facilities. ARAC will add at least two new functions to this capability: centralized, real-time data acquisition and storage, and simulation of the long range atmospheric transport of hazardous materials. To perform these functions, ARAC employs four major sub-systems or facilities: the site facility, the central facility, the global weather center and the regional model. The system has been under development for the past two years at the Lawrence Livermore Laboratory of the University of California. (auth)
Date: December 10, 1975
Creator: Kelly, M.F. & Wyman, R.H.
Object Type: Article
System: The UNT Digital Library
Argonne National Laboratory, Laboratory Directed Research and Development FY 1992 program activities. Annual report (open access)

Argonne National Laboratory, Laboratory Directed Research and Development FY 1992 program activities. Annual report

None
Date: December 10, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Assessment of Aging of Cork and TISAF Materials in the SAFKEG 3940A Package in KAMS (open access)

Assessment of Aging of Cork and TISAF Materials in the SAFKEG 3940A Package in KAMS

This report provides an assessment of the potential for aging and degradation of the resin-bonded cork and the Thermal-Insulating, Shock-Absorbing Foam materials that are components of the SAFKEG 3940A package. This package may be used for interim storage of plutonium materials in the Savannah River Site K-Area Materials Storage.
Date: December 10, 2003
Creator: Vormelker, P.R.
Object Type: Report
System: The UNT Digital Library
Assessment of the safety of US nuclear weapons and related nuclear test requirements: A post-Bush Initiative update (open access)

Assessment of the safety of US nuclear weapons and related nuclear test requirements: A post-Bush Initiative update

The Nuclear Weapons Reduction Initiative announced by President Bush on September 27, 1991, is described herein as set forth in Defense Secretary Cheney`s Nuclear Arsenal Reduction Order issued September 28, 1991. The implications of the Bush Initiative for improved nuclear weapons safety are assessed in response to a request by US Senators Harkin, Kennedy, and Wirth to the Lawrence Livermore National Laboratory that the author prepare such an assessment. The author provides an estimate of the number of nuclear tests needed to accomplish a variety of specified warhead safety upgrades, then uses the results of this estimate to answer three questions posed by the Senators. These questions concern pit reuse and the number of nuclear tests needed for specified safety upgrades of those ballistic missiles not scheduled for retirement, namely the Minuteman III, C4, and D5 missiles.
Date: December 10, 1991
Creator: Kidder, R. E.
Object Type: Report
System: The UNT Digital Library
Atmospheric sciences transfer between research advances and energy-policy assessments (ASTRAEA). Final report, 1 April 1996--31 December 1997 (open access)

Atmospheric sciences transfer between research advances and energy-policy assessments (ASTRAEA). Final report, 1 April 1996--31 December 1997

Consistent with the prime goal of the ASTRAEA project, as given in its peer-reviewed proposal, this final report is an informal report to DOE managers about a perceived DOE management problem, specifically, lack of vision in DOE`s Atmospheric Chemistry Program (ACP). After presenting a review of relevant, current literature, the author suggests a framework for conceiving new visions for ACP, namely, multidisciplinary research for energy policy, tackling tough (e.g., nonlinear) problems as a team, ahead of political curves. Two example visions for ACP are then described, called herein the CITIES Project (the Comprehensive Inventory of Trace Inhalants from Energy Sources Project) and the OCEAN Project (the Ocean-Circulation Energy-Aerosol Nonlinearities Project). Finally, the author suggests methods for DOE to provide ACP with needed vision.
Date: December 10, 1997
Creator: Slinn, W.G.N.
Object Type: Report
System: The UNT Digital Library
Audit of the Department of Energy`s contracts with Envirocare of Utah, Inc (open access)

Audit of the Department of Energy`s contracts with Envirocare of Utah, Inc

The Department of Energy (Department) is responsible for protecting human health and the environment by providing an effective and efficient system that treats, stores, and disposes of Departmental waste. The Department disposes of some of its waste at Envirocare of Utah, Inc., (Envirocare) a commercial treatment and disposal facility in Clive, Utah. The audit objective was to determine whether the Department and its contractors were using the most favorable rates available for the disposal of waste at Envirocare. We found that the Department`s contractors did not always use the most favorable rates available. Although volume discounts were available under Departmentwide contracts, two of the Department`s contractors awarded subcontracts to Envirocare with rates that were higher than the Departmentwide rates. This occurred because the Department did not require contractors to use the most favorable rates available. As a result, the Department has incurred unnecessary costs to dispose of contaminated waste. During the audit, one of the contractors reopened negotiations with Envirocare and obtained a lower rate, thereby saving the Department about $3.2 million over the next 3 years. We recommended that the Deputy Assistant Secretary for Environmental Restoration distribute a list of available Departmentwide contracts and rates and direct field activities …
Date: December 10, 1997
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Auger and Reaction Studies of Poisoning by Sulfur and Regeneration of Metal Synthesis Gas Catalysts. Progress Report, December 8, 1975--December 8, 1976 (open access)

Auger and Reaction Studies of Poisoning by Sulfur and Regeneration of Metal Synthesis Gas Catalysts. Progress Report, December 8, 1975--December 8, 1976

CO methanantion rates have been measured in the all-glass internal recycle reactor developed for this work. The methanation rate over the cylinder Ni film catalyst at 400/sup 0/C is 3.9 sec/sup -1/ initially, and the catalyst undergoes deactivation to a value of 1.8 sec/sup -1/, comparable with a reported value of 2.5 sec/sup -1/. The activation energy for Ni film on alumina is 24 kcal/mole, that for Ni film on silica is 17.8 kcal/mole comparable to values for Ni on these supports. The kinetics suggest that CO dissociation is rate limiting; carbon on the Ni is easily hydrogenated off. H/sub 2/S causes severe deactivation and regeneration after sulfur poisoning is not easily achieved by oxidation in the reactor. However, sulfur is easily removed from Ni by oxygen from a molecular leak in the high-vacuum chamber of the Auger electron spectrometer. Atmospheric pressure studies using an ante-chamber connected to the spectrometer chamber show that sulfur cannot be removed from Ni under conditions similar to those in the reactor because of rapid oxide growth which buries the sulfur preventing removal. Standards allowing determination of concentration as well as chemical state for Ni, O, S, and C have been developed.
Date: December 10, 1976
Creator: Katzer, James R.
Object Type: Report
System: The UNT Digital Library
Automated Eukaryotic Gene Structure Annotation Using EVidenceModeler and the Program to Assemble Spliced Alignments (open access)

Automated Eukaryotic Gene Structure Annotation Using EVidenceModeler and the Program to Assemble Spliced Alignments

EVidenceModeler (EVM) is presented as an automated eukaryotic gene structure annotation tool that reports eukaryotic gene structures as a weighted consensus of all available evidence. EVM, when combined with the Program to Assemble Spliced Alignments (PASA), yields a comprehensive, configurable annotation system that predicts protein-coding genes and alternatively spliced isoforms. Our experiments on both rice and human genome sequences demonstrate that EVM produces automated gene structure annotation approaching the quality of manual curation.
Date: December 10, 2007
Creator: Haas, B. J.; Salzberg, S. L.; Zhu, W; Pertea, M.; Allen, J. E.; Orvis, J. et al.
Object Type: Article
System: The UNT Digital Library
B-physics at CDF (open access)

B-physics at CDF

During the 1988/1989 run at the Fermilab Tevatron, the CDF detector collected {approx equal}4.1 pb{sup {minus}1} of p{bar p} data at {radical}s = 1.8 TeV. The main goals of this run being physics at high p{sub t}, the CDF trigger was tuned'' for maximizing signals from Z{sup 0}s, Ws, t-quarks, etc. As such, compared to the high p{sub t} physics, the b-physics program was of secondary importance other than that which would be used for background calculations. Also, CDF had no vertex chamber capability for seeing displaced vertices. However, significant b-quark, physics results are evident in two data samples; inclusive electrons and inclusive J/{psi} where J/{psi} {yields} {mu}{sup +}{mu}{sup {minus}}. We can then ask ourselves, given all this, why is it that CDF is able to do b-quark physics The answer is that nature has been kind enough to provide b-quarks at an extremely high rate at the Tevatron. The production cross-section for b{bar b} production is quite large. In the rest of this paper, I will try to specify the goals for b-physics using the inclusive electrons and J/{psi} signals for the 1988/1989 data set. I will then provide a brief look at the data, and will finish with …
Date: December 10, 1990
Creator: Baden, A.R. (Harvard Univ., Cambridge, MA (USA))
Object Type: Article
System: The UNT Digital Library
A balancing domain decomposition method by constraints for advection-diffusion problems (open access)

A balancing domain decomposition method by constraints for advection-diffusion problems

The balancing domain decomposition methods by constraints are extended to solving nonsymmetric, positive definite linear systems resulting from the finite element discretization of advection-diffusion equations. A pre-conditioned GMRES iteration is used to solve a Schur complement system of equations for the subdomain interface variables. In the preconditioning step of each iteration, a partially sub-assembled finite element problem is solved. A convergence rate estimate for the GMRES iteration is established, under the condition that the diameters of subdomains are small enough. It is independent of the number of subdomains and grows only slowly with the subdomain problem size. Numerical experiments for several two-dimensional advection-diffusion problems illustrate the fast convergence of the proposed algorithm.
Date: December 10, 2008
Creator: Tu, Xuemin & Li, Jing
Object Type: Article
System: The UNT Digital Library
Band Structure Asymmetry of Bilayer Graphene Revealed by Infrared Spectroscopy (open access)

Band Structure Asymmetry of Bilayer Graphene Revealed by Infrared Spectroscopy

We report on infrared spectroscopy of bilayer graphene integrated in gated structures. We observe a significant asymmetry in the optical conductivity upon electrostatic doping of electrons and holes. We show that this finding arises from a marked asymmetry between the valence and conduction bands, which is mainly due to the inequivalence of the two sublattices within the graphene layer and the next-nearest-neighbor interlayer coupling. From the conductivity data, the energy difference of the two sublattices and the interlayer coupling energy are directly determined.
Date: December 10, 2008
Creator: Li, Z. Q.; Henriksen, E. A.; Jiang, Z.; Hao, Zhao; Martin, Michael C.; Kim, P. et al.
Object Type: Article
System: The UNT Digital Library
BASIC PRINCIPLES OF SCINTILLATION COUNTING (open access)

BASIC PRINCIPLES OF SCINTILLATION COUNTING

The basic principles of scintillation counting are reviewed. The design, performance, and operation of a placed on instruments ior medical uses. (C.H.)
Date: December 10, 1959
Creator: Harris, C.C.; Hamblen, D.P. & Francis, J.E.
Object Type: Report
System: The UNT Digital Library
BDDC for nonsymmetric positive definite and symmetric indefinite problems (open access)

BDDC for nonsymmetric positive definite and symmetric indefinite problems

The balancing domain decomposition methods by constraints are extended to solving both nonsymmetric, positive definite and symmetric, indefinite linear systems. In both cases, certain nonstandard primal constraints are included in the coarse problems of BDDC algorithms to accelerate the convergence. Under the assumption that the subdomain size is small enough, a convergence rate estimate for the GMRES iteration is established that the rate is independent of the number of subdomains and depends only slightly on the subdomain problem size. Numerical experiments for several two-dimensional examples illustrate the fast convergence of the proposed algorithms.
Date: December 10, 2008
Creator: Tu, Xuemin & Li, Jing
Object Type: Article
System: The UNT Digital Library
Beam rounders for circular colliders (open access)

Beam rounders for circular colliders

By means of linear optics, an arbitrary uncoupled beam can be locally transformed into a round (rotation-invariant) state and then back. This provides an efficient way to round beams in the interaction region of circular colliders.
Date: December 10, 2002
Creator: Nagaitsev, A. Burov and S.
Object Type: Article
System: The UNT Digital Library