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Technical Risk Rating of DOE Environmental Projects - 9153

Description: The U.S. Department of Energy's Office of Environmental Management (DOE-EM) was established to achieve the safe and compliant disposition of legacy wastes and facilities from defense nuclear applications. The scope of work is diverse, with projects ranging from single acquisitions to collections of projects and operations that span several decades and costs from hundreds of millions to billions US$. The need to be able to manage and understand the technical risks from the project to senior mana… more
Date: February 11, 2009
Creator: Cercy, Michael; Fayfich, Ronald & Schneider, Steven
Partner: UNT Libraries Government Documents Department
open access

Loss Factor of the PEP-II Rings

Description: An RF power balance method is used to measure the synchrotron radiation losses and the wake field losses. We present the history of the losses in the Low Energy Ring (LER) and the High Energy Ring (HER) during the last several runs of PEP-II.
Date: July 11, 2008
Creator: Novokhatski, A. & Sullivan, M.
Partner: UNT Libraries Government Documents Department
open access

Multiple Valley Couplings in Nanometer Si MOSFETs

Description: We investigate the couplings between different energy band valleys in a MOSFET device using self-consistent calculations of million-atom Schroedinger-Poisson Equations. Atomistic empirical pseudopotentials are used to describe the device Hamiltonian and the underlying bulk band structure. The MOSFET device is under nonequilibrium condition with a source-drain bias up to 2V, and a gate potential close to the threshold potential. We find that all the intervalley couplings are small, with the coup… more
Date: July 11, 2008
Creator: Wang, Lin-Wang; Deng, Hui-Xiong; Jiang, Xiang-Wei; Luo, Jun-Wei; Li, Shu-Shen; Xia, Jian-Bai et al.
Partner: UNT Libraries Government Documents Department
open access

Pathway confirmation and flux analysis of central metabolicpathways in Desulfovibrio vulgaris Hildenborough using gaschromatography-mass spectrometry and fourier transform-ion cyclotronresonance mass spectrometry

Description: It has been proposed that during growth under anaerobic oroxygen-limited conditions Shewanella oneidensis MR-1 uses theserine-isocitrate lyase pathway common to many methylotrophic anaerobes,in which formaldehyde produced from pyruvate is condensed with glycine toform serine. The serine is then transformed through hydroxypyruvate andglycerate to enter central metabolism at phosphoglycerate. To examine itsuse of the serine-isocitrate lyase pathway under anaerobic conditions, wegrew S. oneidensis… more
Date: July 11, 2006
Creator: Tang, Yinjie; Pingitore, Francesco; Mukhopadhyay, Aindrila; Phan,Richard; Hazen, Terry C. & Keasling, Jay D.
Partner: UNT Libraries Government Documents Department
open access

MODEL-BASED HYDROACOUSTIC BLOCKAGE ASSESSMENT AND DEVELOPMENT OF AN EXPLOSIVE SOURCE DATABASE

Description: We are continuing the development of the Hydroacoustic Blockage Assessment Tool (HABAT) which is designed for use by analysts to predict which hydroacoustic monitoring stations can be used in discrimination analysis for any particular event. The research involves two approaches (1) model-based assessment of blockage, and (2) ground-truth data-based assessment of blockage. The tool presents the analyst with a map of the world, and plots raypath blockages from stations to sources. The analyst inp… more
Date: July 11, 2005
Creator: Matzel, E; Ramirez, A & Harben, P
Partner: UNT Libraries Government Documents Department
open access

The Surface Wave Magnitude for the 9 October 2006 North Korean Nuclear Explosion

Description: Surface waves were generated by the North Korean nuclear explosion of 9 October 2006 and recorded at epicentral distances up to 34 degrees, from which we estimated a surface wave magnitude (M{sub s}) of 2.94 with an interstation standard deviation of 0.17 magnitude units. The International Data Centre estimated a body wave magnitude (m{sub b}) of 4.1. This is the only explosion we have analyzed that was not easily screened as an explosion based on the differences between the M{sub s} and m{sub … more
Date: March 11, 2008
Creator: Bonner, J; Herrmann, R; Harkrider, D & Pasyanos, M
Partner: UNT Libraries Government Documents Department
open access

Electronic structure of multiferroic BiFeO3 by resonant soft-x-ray emission spectroscopy

Description: The electronic structure of multiferroic BiFeO{sub 3} has been studied using soft-X-ray emission spectroscopy. The fluorescence spectra exhibit that the valence band is mainly composed of O 2p state hybridized with Fe 3d state. The band gap corresponding to the energy separation between the top of the O 2p valence band and the bottom of the Fe 3d conduction band is 1.3 eV. The soft-X-ray Raman scattering reflects the features due to charge transfer transition from O 2p valence band to Fe 3d con… more
Date: July 11, 2008
Creator: Higuchi, Tohru; Higuchi, T.; Liu, Y.-S.; Yao, P.; Glans, P.-A.; Guo, Jinghua et al.
Partner: UNT Libraries Government Documents Department
open access

SUSY Without Prejudice at Linear Colliders

Description: We explore the physics of the general CP-conserving MSSM with Minimal Flavor Violation, the pMSSM. The 19 soft SUSY breaking parameters are chosen so to satisfy all existing experimental and theoretical constraints assuming that the WIMP is the lightest neutralino. We scan this parameter space twice using both flat and log priors and compare the results which yield similar conclusions. Constraints from both LEP and the Tevatron play an important role in obtaining our final model samples. Implic… more
Date: December 11, 2008
Creator: Rizzo, Thomas G.
Partner: UNT Libraries Government Documents Department
open access

CLOMP: Accurately Characterizing OpenMP Application Overheads

Description: Despite its ease of use, OpenMP has failed to gain widespread use on large scale systems, largely due to its failure to deliver sufficient performance. Our experience indicates that the cost of initiating OpenMP regions is simply too high for the desired OpenMP usage scenario of many applications. In this paper, we introduce CLOMP, a new benchmark to characterize this aspect of OpenMP implementations accurately. CLOMP complements the existing EPCC benchmark suite to provide simple, easy to unde… more
Date: February 11, 2008
Creator: Bronevetsky, G; Gyllenhaal, J & de Supinski, B
Partner: UNT Libraries Government Documents Department
open access

The influence of projectile neutron number in the 208Pb(48Ti, n)255Rf and 208Pb(50Ti, n)257Rf reactions

Description: Four isotopes of rutherfordium,254-257Rf, were produced by the 208Pb(48Ti, xn)256-xRf and 208Pb(50Ti, xn)258-xRf reactions (x = 1, 2) at the Lawrence Berkeley National Laboratory 88-Inch Cyclotron. Excitation functions were measured for the 1n and 2n exit channels. A maximum likelihood technique, which correctly accounts for the changing cross section at all energies subtended by the targets, was used to fit the 1n data to allow a more direct comparison between excitation functions obtained und… more
Date: July 11, 2008
Creator: Dragojevic, Irena; Dragojevic, I.; Gregorich, K. E.; Dullmann, Ch. E.; Garcia, M. A.; Gates, J. M. et al.
Partner: UNT Libraries Government Documents Department
open access

On the Suitability of Lanthanides as Actinide Analogs

Description: With the current level of actinide materials used in civilian power generation and the need for safe and efficient methods for the chemical separation of these species from their daughter products and for long-term storage requirements, a detailed understanding of actinide chemistry is of great importance. Due to the unique bonding properties of the f-elements, the lanthanides are commonly used as structural and chemical models for the actinides, but differences in the bonding between these 4f … more
Date: April 11, 2008
Creator: Szigethy, Geza & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department
open access

Fluidized Bed Steam Reforming Mineralization for High Organic and Nitrate Waste Streams for the Global Nuclear Energy Partnership

Description: Waste streams that may be generated by the Global Nuclear Energy Partnership (GNEP) Advanced Energy Initiative may contain significant quantities of organics (0-53 wt%) and/or nitrates (0-56 wt%). Decomposition of high nitrate streams requires reducing conditions, e.g. organic additives such as sugar or coal, to reduce the NO{sub x} in the off-gas to N{sub 2} to meet the Clean Air Act (CAA) standards during processing. Thus, organics will be present during waste form stabilization regardless of… more
Date: January 11, 2008
Creator: Jantzen, Carol M. & Williams, M. R.
Partner: UNT Libraries Government Documents Department
open access

Syntheses, Structure, Magnetism, and Optical Properties of the Interlanthanide Sulfides delta-Ln2-xLuxS3 (Ln = Ce, Pr, Nd)

Description: {delta}-Ln{sub 2-x}LuxS{sub 3} (Ln = Ce, Pr, Nd; x = 0.67-0.71) compounds have been synthesized through the reaction of elemental rare earth metals and S using Sb{sub 2}S{sub 3} flux at 1000 C. These compounds are isotypic with CeTmS{sub 3}, which has a complex three-dimensional structure. It includes four larger Ln{sup 3+} sites in eight- and nine-coordinate environments, two disordered seven-coordinate Ln{sup 3+}/Lu{sup 3+} positions, and two six-coordinate Lu{sup 3+} ions. The structure is c… more
Date: January 11, 2008
Creator: Booth, Corwin H; Jin, Geng Bang; Choi, Eun Sang; Guertin, Robert P.; Brooks, James S.; Bray, Travis H. et al.
Partner: UNT Libraries Government Documents Department
open access

Hadronic B decays at BaBar and Belle

Description: The authors review recent results of the BABAR and Belle Collaborations on the {alpha} and {gamma} angles of the unitarity triangle, on the B {yields} K{pi}{pi} Dalitz-plot analyses, and on the searches for baryonic B decays and for B {yields} D{bar D} decays.
Date: August 11, 2008
Creator: Lombardo, Vincenzo
Partner: UNT Libraries Government Documents Department
open access

Requirements for Reactor Physics Design

Description: It has been recognized that there is a need for requirements and guidance for design and operation of nuclear power plants. This is becoming more important as more reactors are being proposed to be built. In parallel with activities in individual countries are norms established by international organizations. This paper discusses requirements/guidance for neutronic design and operation as promulgated by the U.S. Nuclear Regulatory Commission (NRC). As an example, details are given for one react… more
Date: April 11, 2008
Creator: Diamond, D. J.
Partner: UNT Libraries Government Documents Department
open access

ON THE IMPACT OF SUPER RESOLUTION WSR-88D DOPPLER RADAR DATA ASSIMILATION ON HIGH RESOLUTION NUMERICAL MODEL FORECASTS

Description: Assimilation of radar velocity and precipitation fields into high-resolution model simulations can improve precipitation forecasts with decreased 'spin-up' time and improve short-term simulation of boundary layer winds (Benjamin, 2004 & 2007; Xiao, 2008) which is critical to improving plume transport forecasts. Accurate description of wind and turbulence fields is essential to useful atmospheric transport and dispersion results, and any improvement in the accuracy of these fields will make cons… more
Date: January 11, 2009
Creator: Chiswell, S
Partner: UNT Libraries Government Documents Department
open access

Discretizing gravity in warped spacetime

Description: We investigate the discretized version of the compact Randall-Sundrum model. By studying the mass eigenstates of the lattice theory, we demonstrate that for warped space, unlike for flat space, the strong coupling scale does not depend on the IR scale and lattice size. However, strong coupling does prevent us from taking the continuum limit of the lattice theory. Nonetheless, the lattice theory works in the manifestly holographic regime and successfully reproduces the most significant features … more
Date: July 11, 2005
Creator: Schwartz, Matthew; Randall, Lisa; Schwartz, Matthew D. & Thambyahpillai, Shiyamala
Partner: UNT Libraries Government Documents Department
open access

Demonstartion of density dependence of x-ray flux in a laser-driven hohlraum

Description: Experiments have been conducted using laser-driven cylindrical hohlraums whose walls are machined from Ta{sub 2}O{sub 5} foams of 100 mg/cc and 4 g/cc densities. Measurements of the radiation temperature demonstrate that the lower density walls produce higher radiation temperatures than the high density walls. This is the first experimental demonstration of the prediction that this would occur [M. D. Rosen and J. H. Hammer, Phys. Rev. E 72, 056403 (2005)]. For high density walls, the radiation … more
Date: February 11, 2008
Creator: Young, P E; Rosen, M D; Hammer, J H; Hsing, W S; Glendinning, S G; Turner, R E et al.
Partner: UNT Libraries Government Documents Department
open access

Time-resolved soft-x-ray spectroscopy of a magnetic octupole transition in nickel-like xenon, cesium, and barium ions

Description: A microcalorimeter with event mode capability for time-resolved soft-x-ray spectroscopy, and a high-resolution flat-field EUV spectrometer have been employed at the Livermore EBIT-I electron beam ion trap for observations and wavelength measurements of M1, E2, and M3 decays of long-lived levels in the Ni-like ions Xe{sup 26+}, Cs{sup 27+}, and Ba{sup 28+}. Of particular interest is the lowest excited level, 3d{sup 9}4s {sup 3}D{sub 3}, which can only decay via a magnetic octupole (M3) transitio… more
Date: November 11, 2005
Creator: Trabert, E; Beiersdorfer, P; Brown, G V; Boyce, K; Kelley, R L; Kilbourne, C A et al.
Partner: UNT Libraries Government Documents Department
open access

Global paths of time-periodic solutions of the Benjamin-Ono equation connecting arbitrary traveling waves

Description: We classify all bifurcations from traveling waves to non-trivial time-periodic solutions of the Benjamin-Ono equation that are predicted by linearization. We use a spectrally accurate numerical continuation method to study several paths of non-trivial solutions beyond the realm of linear theory. These paths are found to either re-connect with a different traveling wave or to blow up. In the latter case, as the bifurcation parameter approaches a critical value, the amplitude of the initial condi… more
Date: December 11, 2008
Creator: Ambrose, David M. & Wilkening, Jon
Partner: UNT Libraries Government Documents Department
open access

Hybrid MOSFET/Driver for Ultra-Fast Switching

Description: The ultra-fast switching of power MOSFETs, in {approx}1ns, is very challenging. This is largely due to the parasitic inductance that is intrinsic to commercial packages used for both MOSFETs and drivers. Parasitic gate and source inductance not only limit the voltage rise time on the MOSFET internal gate structure but can also cause the gate voltage to oscillate. This paper describes a hybrid approach that substantially reduces the parasitic inductance between the driver and MOSFET gate as well… more
Date: July 11, 2008
Creator: Tang, T. & Burkhart, C.
Partner: UNT Libraries Government Documents Department
open access

HYDROGEN EFFECTS ON STRAIN-INDUCED MARTENSITE FORMATION IN TYPE 304L STAINLESS STEEL

Description: Unstable austenitic stainless steels undergo a strain-induced martensite transformation. The effect of hydrogen on this transformation is not well understood. Some researchers believe that hydrogen makes the transformation to martensite more difficult because hydrogen is an austenite stabilizer. Others believe that hydrogen has little or no effect at all on the transformation and claim that the transformation is simply a function of strain and temperature. Still other researchers believe that h… more
Date: December 11, 2008
Creator: Morgan, M & Ps Lam, P
Partner: UNT Libraries Government Documents Department
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