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Applications of small computers for systems control on the Tandem Mirror Experiment-Upgrade

Description: Desktop computers operating into a CAMAC-based interface are used to control and monitor the operation of the various subsystems on the Tandem Mirror Experiment-Upgrade (TMX-U) at Lawrence Livermore National Laboratory (LLNL). These systems include: shot sequencer/master timing, neutral beam control (four consoles), magnet power system control, ion-cyclotron resonant heating (ICRH) control, thermocouple monitoring, getter system control, gas fueling system control, and electron-cyclotron resona… more
Date: November 29, 1983
Creator: Bork, R. G.; Kane, R. J. & Moore, T. L.
Partner: UNT Libraries Government Documents Department
open access

High energy negative deuterium beams using double charge-exchange or surface production

Description: Experimental and theoretical research on production of negative ion beams is described. Results from a double charge-exchange experiment include 10 ms pulses of 100 ma of D/sup -/ accelerated to 60 kV. Equilibrium fractions of D/sup -/ in several metal vapors are presented. Mechanisms and measurements of D/sup -/ on surfaces are described, and a scheme is shown for producing high current, high energy beams originating on surfaces.
Date: November 29, 1977
Creator: Hooper, E. B. Jr.; Anderson, O. A.; Orzechowski, T. & Poulsen, P.
Partner: UNT Libraries Government Documents Department
open access

Mirror research: status and prospects

Description: The tandem mirror program has evolved considerably in the last decade. Of significance is the viable reactor concept embodied in the MARS design. An aggressive experimental program culminating in the operation of MFTF-B in late 1986, will provide a firm basis for refining the MARS design as necessary for constructing a reactor prototype in the 1990s.
Date: November 29, 1983
Creator: Baldwin, D.E.
Partner: UNT Libraries Government Documents Department
open access

TREATABILITY TEST FOR REMOVING TECHNETIUM-99 FROM 200-ZP-1 GROUNDWATER HANFORD SITE

Description: The 200-ZP-1 Groundwater Operable Unit (OU) is one of two groundwater OUs located within the 200 West groundwater aggregate area of the Hanford Site. The primary risk-driving contaminants within the 200-ZP-1 OU include carbon tetrachloride and technetium-99 (Tc-99). A pump-and-treat system for this OU was initially installed in 1995 to control the 0.002 kg/m{sup 3} (2000 {micro}g/L) contour of the carbon tetrachloride plume. Carbon tetrachloride is removed from groundwater with the assistance o… more
Date: November 29, 2007
Creator: SW, PETERSEN; AC, TORTOSO; WS, ELLIOTT & ME, BYRNES
Partner: UNT Libraries Government Documents Department
open access

Chemical reaction rates using the semiclassical Van-Vleck initialvalue representation

Description: A semiclassical IVR formulation using the Van-Vleck propagator has been used to calculate the flux correlation function and thereby reaction rate constants. This Van-Vleck formulation of the flux-flux correlation function is computationally as simple as the classical Wigner model. However unlike the latter, it has the ability to capture quantum interference/coherence effects. Classical trajectories are evolved starting from the dividing surface that separates reactants and products, and are evo… more
Date: November 29, 2006
Creator: Venkataraman, Charulatha & Miller, William H.
Partner: UNT Libraries Government Documents Department
open access

Evidence for Merging or Disruption of Red Galaxies from the Evolution of Their Clustering

Description: The formation and evolution of massive red galaxies form a crucial test of theories of galaxy formation based on hierarchical assembly. In this Letter we use observations of the clustering of luminous red galaxies from the Boötes field and N-body simulations to argue that about of the most luminous satellite galaxies appear to undergo merging or disruption within massive halos between and 0.5.
Date: November 29, 2006
Creator: White, Martin; White, Martin; Zheng, Zheng; Brown, Michael J. I.; Dey, Arjun & Jannuzi, Buell T.
Partner: UNT Libraries Government Documents Department
open access

SALT CORE SAMPLING EVOLUTION AT THE SAVANNAH RIVER SITE

Description: The Savannah River Site (SRS), a Department of Energy (DOE) facility, has over 30 million gallons of legacy waste from its many years of processing nuclear materials. The majority of waste is stored in 49 buried tanks. Available underground piping is the primary and desired pathway to transfer waste from one tank to another until the waste is delivered to the glass plant, DWPF, or the grout plant, Saltstone. Prior to moving the material, the tank contents need to be evaluated to ensure the corr… more
Date: November 29, 2007
Creator: Nance, T; Daniel Krementz, D & William Cheng, W
Partner: UNT Libraries Government Documents Department
open access

Comparison of kinetic and equilibrium reaction models insimulating gas hydrate behavior in porous media

Description: In this study we compare the use of kinetic and equilibriumreaction models in the simulation of gas (methane) hydrate behavior inporous media. Our objective is to evaluate through numerical simulationthe importance of employing kinetic versus equilibrium reaction modelsfor predicting the response of hydrate-bearing systems to externalstimuli, such as changes in pressure and temperature. Specifically, we(1) analyze and compare the responses simulated using both reactionmodels for natural gas pro… more
Date: November 29, 2006
Creator: Kowalsky, Michael B. & Moridis, George J.
Partner: UNT Libraries Government Documents Department
open access

Extreme Ultraviolet Imaging of Electron Heated Targets in Petawatt Laser Experiments

Description: The study of the transport of electrons, and the flow of energy into a solid target or dense plasma, is instrumental in the development of fast ignition inertial confinement fusion. An extreme ultraviolet (XUV) imaging diagnostic at 256 eV and 68 eV provides information about heating and energy deposition within petawatt laser-irradiated targets. XUV images of several irradiated solid targets are presented.
Date: November 29, 2007
Creator: Ma, T.; MacPhee, A.; Key, M.; Akli, K.; Mackinnon, A.; Chen, C. et al.
Partner: UNT Libraries Government Documents Department
open access

Two-photon Photo-emission of Ultrathin Film PTCDA Morphologies on Ag(111)

Description: Morphology- and layer-dependent electronic structure and dynamics at the PTCDA/Ag(111) interface have been studied with angle-resolved two-photon photoemission. In Stranski-Krastanov growth modes, the exposed wetting layer inhibited the evolution of the vacuum level and valence band to bulk values. For layer-by-layer growth, we observed the transition of electron structure from monolayer to bulk values within eight monolayers. Effective masses and lifetimes of the conduction band and the n=1 im… more
Date: November 29, 2007
Creator: Yang, Aram; Yang, Aram; Shipman, Steven T.; Garrett-Roe, Sean; Johns, James; Strader, Matt et al.
Partner: UNT Libraries Government Documents Department
open access

TREATABILITY TEST PLAN FOR DEEP VADOSE ZONE REMEDIATION AT THE HANFORD SITE CENTRAL PLATEAU

Description: A treatability test plan has been prepared to address options for remediating portions of the deep vadose zone beneath a portion of the U.S. Department of Energy's (DOE's) Hanford Site. The vadose zone is the region of the subsurface that extends from the ground surface to the water table. The overriding objective of the treatability test plan is to recommend specific remediation technologies and laboratory and field tests to support the Comprehensive Environmental Response, Compensation, and L… more
Date: November 29, 2007
Creator: SW, PETERSEN; JG, MORSE; MJ, TRUEX & GV, LAST
Partner: UNT Libraries Government Documents Department
open access

Inertial Fusion Energy's Role in Developing the Market for High Power Laser Diodes

Description: Production-cost models for high-power laser-diodes indicate systems of 10GW peak power coupled with facilitization of semi-conductor manufacturing capacity could yield costs below $0.02/Watt. This is sufficient to make IFE competitive with other nuclear power technologies.
Date: November 29, 2007
Creator: Ladran, A. L.; Ault, E. R.; Beach, R. J.; Campbell, J. H.; Erlandson, A. C.; Felker, A. J. et al.
Partner: UNT Libraries Government Documents Department
open access

Keck Observations of the 2002-2003 Jovian Ring Plane Crossing

Description: We present new observations of Jupiter's ring system at a wavelength of 2.2 {micro}m obtained with the 10-m W. M. Keck telescopes on three nights during a ring plane crossing: UT 19 December 2002, and 22 and 26 January 2003. We used conventional imaging, plus adaptive optics on the last night. Here we present detailed radial profiles of the main ring, halo and gossamer rings, and interpret the data together with information extracted from radio observations of Jupiter's synchrotron radiation. T… more
Date: November 29, 2007
Creator: de Pater, I.; Showalter, M. R. & Macintosh, B. A.
Partner: UNT Libraries Government Documents Department
open access

Comparison of kinetic and equilibrium reaction models insimulating the behavior of porous media

Description: In this study we compare the use of kinetic and equilibriumreaction models in the simulation of gas (methane) hydrate behavior inporous media. Our objective is to evaluate through numerical simulationthe importance of employing kinetic versus equilibrium reaction modelsfor predicting the response of hydrate-bearing systems to externalstimuli, such as changes in pressure and temperature. Specifically, we(1) analyze and compare the responses simulated using both reactionmodels for natural gas pro… more
Date: November 29, 2006
Creator: Kowalsky, Michael B. & Moridis, George J.
Partner: UNT Libraries Government Documents Department
open access

Advanced design and modeling concepts for recombination x-ray lasers

Description: Geometric, kinetic, and trapping issues, in short and ultrashort recombination x-ray lasers, are discussed. The design of a composite target consisting of a lasant strip on a plastic backing is described. Examples of modeling showing the effect of photon trapping and uncertainties in other physical processes on calculated gain coefficients are given. A simple and accurate expression for photon trapping in cylindrical geometry is presented. Recombination lasers that have the ground state as the … more
Date: November 29, 1990
Creator: Eder, D.C.; Rosen, M.D.; Shephard, R.; Staffin, R.; Nash, J.K. & Keane, C.J.
Partner: UNT Libraries Government Documents Department
open access

Improved ground-penetrating radar, bridge decks

Description: Inspection of high-value structures, like bridges and buildings, using Ground Penetrating Radar (GPR) is an application of a technology that is growing in importance. In a typical inspection application, inspectors use GPR to locate structural components, like embedded reinforcing bars, to avoid weakening the structure while collecting core samples for detailed inspection. Advanced GPR, integrated with imaging technologies for use as an NDE tool, can provide the capability to quickly locate and… more
Date: November 29, 1993
Creator: Warhus, J. P.; Mast, J. E.; Johansson, E. M. & Nelson, S. D.
Partner: UNT Libraries Government Documents Department
open access

Elastic spin observables and proton wave function normalization at large t

Description: We summarize the role of spin observables in testing the foundations of exclusive QCD at large t. Polarized elastic scattering experiments can shed light on fundamental properties of protons, such as helicity conservation, normalization of the wave function and structure. Specific QCD motivated predictions for the spin observables are presented, which can be tested at polarized proton beam facilities. In this paper, two kinematic regions are considered: 90{degrees} c.m. at large {vert_bar} t {v… more
Date: November 29, 1993
Creator: Ramsey, G. P.
Partner: UNT Libraries Government Documents Department
open access

A Sequential Fluid-mechanic Chemical-kinetic Model of Propane HCCI Combustion

Description: We have developed a methodology for predicting combustion and emissions in a Homogeneous Charge Compression Ignition (HCCI) Engine. This methodology combines a detailed fluid mechanics code with a detailed chemical kinetics code. Instead of directly linking the two codes, which would require an extremely long computational time, the methodology consists of first running the fluid mechanics code to obtain temperature profiles as a function of time. These temperature profiles are then used as inp… more
Date: November 29, 2000
Creator: Aceves, S M; Flowers, D L; Martinez-Frias, J; Smith, J R; Westbrook, C; Pitz, W et al.
Partner: UNT Libraries Government Documents Department
open access

StralSV: assessment of sequence variability within similar 3D structures and application to polio RNA-dependent RNA polymerase

Description: Most of the currently used methods for protein function prediction rely on sequence-based comparisons between a query protein and those for which a functional annotation is provided. A serious limitation of sequence similarity-based approaches for identifying residue conservation among proteins is the low confidence in assigning residue-residue correspondences among proteins when the level of sequence identity between the compared proteins is poor. Multiple sequence alignment methods are more s… more
Date: November 29, 2010
Creator: Zemla, A; Lang, D; Kostova, T; Andino, R & Zhou, C
Partner: UNT Libraries Government Documents Department
open access

A Test of HTS Power Cable in a Sweeping Magnetic Field

Description: Short sample HTS power cable composed of multiple 344C-2G strands and designed to energize a fast-cycling dipole magnet was exposed to a sweeping magnetic field in the (2-20) T/s ramping rate. The B-field orientation toward the HTS strands wide surface was varied from 0{sup 0} to 10{sup 0}, in steps of 1{sup 0}. The test arrangement allowed measurement of the combined hysteresis and eddy current power losses. For the validity of these measurements, the power losses of a short sample cable compo… more
Date: November 29, 2011
Creator: Piekarz, H.; Hays, S.; Blowers, J. & Shiltsev, V.
Partner: UNT Libraries Government Documents Department
open access

Simulation of Prompt Emission from GRBs with a Photospheric Component and its Detectability By GLAST

Description: The prompt emission from gamma-ray bursts (GRBs) still requires a physical explanation. Studies of time-resolved GRB spectra, observed in the keV-MeV range, show that a hybrid model consisting of two components, a photospheric and a non-thermal component, in many cases fits bright, single-pulsed bursts as well as, and in some instances even better than, the Band function. With an energy coverage from 8 keV up to 300 GeV, GLAST will give us an unprecedented opportunity to further investigate the… more
Date: November 29, 2011
Creator: Battelino, Milan; Ryde, Felix; Observ., /Stockholm; Omodei, Nicola; /INFN, Pisa; Longo, Francesco et al.
Partner: UNT Libraries Government Documents Department
open access

Massive Stars in Colliding Wind Systems: the GLAST Perspective

Description: Colliding winds of massive stars in binary systems are considered as candidate sites of high-energy non-thermal photon emission. They are already among the suggested counterparts for a few individual unidentified EGRET sources, but may constitute a detectable source population for the GLAST observatory. The present work investigates such population study of massive colliding wind systems at high-energy gamma-rays. Based on the recent detailed model (Reimer et al. 2006) for non-thermal photon pr… more
Date: November 29, 2011
Creator: Reimer, Anita; Reimer, Olaf & /Stanford U., HEPL /KIPAC, Menlo Park
Partner: UNT Libraries Government Documents Department
open access

Calibration of the GLAST Burst Monitor Detectors

Description: The GLAST Burst Monitor (GBM) will augment the capabilities of GLAST for the detection of cosmic gamma-ray bursts by extending the energy range (20 MeV to > 300 GeV) of the Large Area Telescope (LAT) towards lower energies by 2 BGO-detectors (150 keV to 30 MeV) and 12 NaI(Tl) detectors (10 keV to 1 MeV). The physical detector response of the GBM instrument for GRBs is determined with the help of Monte Carlo simulations, which are supported and verified by on-ground calibration measurements, … more
Date: November 29, 2011
Creator: von Kienlin, Andreas; Bissaldi, Elisabetta; Lichti, Giselher G.; Steinle, Helmut; Krumrey, Michael; Gerlach, Martin et al.
Partner: UNT Libraries Government Documents Department
open access

Analysis Efforts Supporting NSTX Upgrades

Description: The National Spherical Torus Experiment (NSTX) is a low aspect ratio, spherical torus (ST) configuration device which is located at Princeton Plasma Physics Laboratory (PPPL) This device is presently being updated to enhance its physics by doubling the TF field to 1 Tesla and increasing the plasma current to 2 Mega-amperes. The upgrades include a replacement of the centerstack and addition of a second neutral beam. The upgrade analyses have two missions. The first is to support design of new co… more
Date: November 29, 2010
Creator: H.Zhang, P. Titus, P. Rogoff, A.Zolfaghari, D. Mangra, M. Smith
Partner: UNT Libraries Government Documents Department
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