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Computation of self-consistent 2-D MHD with neutral-beam and bootstrap currents in elongated plasmas

Description: The observation of substantial current drive from neutral beam injection (NBI) in TFTR, JET and DIII-D has led to renewed interest in a steady state, non-inductively driven tokamak. The discovery of apparently considerable neoclassical (bootstrap) current in TFTR, makes a steady state device even more attractive since the bootstrap portion of the current could be obtained without additional power input. Motivated by these results, we have developed a code, ACCOME, which self-consistently comput… more
Date: April 5, 1983
Creator: Devoto, R. S.; Tani, K. & Azumi, M.
Partner: UNT Libraries Government Documents Department
open access

Formation of H/sup -/ by charge transfer in alkaline-earth vapors

Description: Progress since the last symposium on the study of H/sup -/ formation by charge transfer in alkaline-earth vapors is reported. High yields are obtained at low energies, in agreement with theoretical predictions.
Date: December 5, 1983
Creator: Schlachter, A.S. & Morgan, T.J.
Partner: UNT Libraries Government Documents Department
open access

Shiva automatic pinhole alignment

Description: This paper describes a computer controlled closed loop alignment subsystem for Shiva, which represents the first use of video sensors for large laser alignment at LLNL. The techniques used on this now operational subsystem are serving as the basis for all closed loop alignment on Nova, the 200 terawatt successor to Shiva.
Date: September 5, 1980
Creator: Suski, G.J.
Partner: UNT Libraries Government Documents Department
open access

Time resolution performance studies of contemporary high speed photomultipliers

Description: The time resolution capabilities of prototype microchannel plate and static crossed-field photomultipliers have been investigated. Measurements were made of electron transit time, rise time, time response, single photoelectron time spread and multiphotoelectron time spread for LEP HR350 proximity focused high gain curved microchannel plate and VPM-154A/1.6L static crossed-field photomultipliers. The experimental data have been compared with results obtained with conventionally designed RCS 8850… more
Date: October 5, 1977
Creator: Leskovar, B. & Lo, C.C.
Partner: UNT Libraries Government Documents Department
open access

Three-dimensional thermal analysis of a baseline spent fuel repository

Description: A three-dimensional thermal analysis has been performed using finite difference techniques to determine the near-field response of a baseline spent fuel repository in a deep geologic salt medium. A baseline design incorporates previous thermal modeling experience and OWI recommendations for areal thermal loading in specifying the waste form properties, package details, and emplacement configuration. The base case in this thermal analysis considers one 10-year old PWR spent fuel assembly emplace… more
Date: June 5, 1980
Creator: Altenbach, T.J. & Lowry, W.E.
Partner: UNT Libraries Government Documents Department
open access

Axicell MFTF-B superconducting-magnet system

Description: The Axicell MFTF-B magnet system will provide the field environment necessary for tandem mirror plasma physics investigation with thermal barriers. The performance of the device will stimulate DT to achieve energy break-even plasma conditions. Operation will be with deuterium only. There will be 24 superconducting coils consisting of 2 sets of yin-yang pairs, 14 central-cell solenoids, 2 sets of axicell mirror-coil pairs, and 2 transition coils between the axicell mirror coil-pairs and the yin-… more
Date: May 5, 1982
Creator: Wang, S. T.; Bulmer, R.; Hanson, C.; Hinkle, R.; Kozman, T.; Shimer, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Chemiluminescence from the reaction of Ba /sup 3/D with nitric oxide

Description: The reaction of laser excited Ba*(/sup 3/D) states with nitric oxide is presented. BaO product is not detected, although the channel is thermodynamically open, and instead chemiluminescence is observed. Experiments which suggest that radiative recombination, Ba + NO ..-->.. BaNO* ..-->.. BaNO, is the observed reaction channel will also be presented.
Date: January 5, 1977
Creator: Johnson, S. A.; Solarz, R. W.; Dubrin, J. W. & Brotzmann, R.
Partner: UNT Libraries Government Documents Department
open access

Inertial fusion research at Lawrence Livermore National Laboratory: program status and future applications

Description: The objectives of the Lawrence Livermore National Laboratory (LLNL) Laser Fusion Program are to understand and develop the science and technology required to utilize inertial confinement fusion (ICF) for both military and commercial applications. The results of recent experiments are described. We point out the progress in our laser studies, where we continue to develop and test the concepts, components, and materials for present and future laser systems. While there are many potential commerci… more
Date: June 5, 1986
Creator: Meier, W. R. & Hogan, W. J.
Partner: UNT Libraries Government Documents Department
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Holographic and acoustic emission evaluation of pressure vessels

Description: Optical holographic interfereometry and acoustic emission monitoring were simultaneously used to evaluate two small, high pressure vessels during pressurization. The techniques provide pressure vessel designers with both quantitative information such as displacement/strain measurements and qualitative information such as flaw detection. The data from the holographic interferograms were analyzed for strain profiles. The acoustic emission signals were monitored for crack growth and vessel quality. more
Date: March 5, 1980
Creator: Boyd, D.M.
Partner: UNT Libraries Government Documents Department
open access

Cryopumping system for TFTR neutral beam injectors

Description: The cryocondensation pumping system for the TFTR neutral beam injectors is described. Topics include hardware design, differential pumping and beam loss, operational modes, and response to massive vacuum breaks.
Date: October 5, 1977
Creator: Valby, L.E.
Partner: UNT Libraries Government Documents Department
open access

Application of digital image analysis techniques to the Geyser's data and topography

Description: This paper describes the results of digital image analysis and techniques applied to acoustic sounder data and topographic relief in the Geyser's region. The two dimensional fast Fourier transform (2DFFT) represents the spacial variability of a photographic image. The spacial variability of topography in complex terrain can be represented in this way and insight into degree of complexity and dominating spacial wavelengths can be gained. This was performed for a 16 km square digitized topographi… more
Date: May 5, 1980
Creator: Porch, W.M.
Partner: UNT Libraries Government Documents Department
open access

Mechanisms of defect production and atomic mixing in high energy displacement cascades: A molecular dynamics study

Description: We have performed molecular dynamics computer simulation studies of displacement cascades in Cu at low temperature. For 25 keV recoils we observe the splitting of a cascade into subcascades and show that cascades in Cu may lead to the formation of vacancy and interstitial dislocation loops. We discuss a new mechanism of defect production based on the observation of interstitial prismatic dislocation loop punching from cascades at 10 K. We also show that below the subcascade threshold, atomic mi… more
Date: June 5, 1991
Creator: Diaz de la Rubia, T. & Guinan, M.W.
Partner: UNT Libraries Government Documents Department
open access

Development of an x-ray framing camera

Description: We are presently developing an ultrafast x-ray framing camera, to be used in laser fusion experiments on the NOVA facility at LLNL. The framing camera will provide high-fidelity images with frame durations of less than 100 ps. The first prototype camera will generate a single image approximately one square centimeter in area, with a spatial resolution of approx.30 microns at the image plane. Coupling the framing camera to a 22 x Wolter x-ray microscope will provide resolution at the target of a… more
Date: March 5, 1986
Creator: Stearns, D.G.; Wiedwald, J.; Cook, B.M. & Hanks, R.
Partner: UNT Libraries Government Documents Department
open access

Recent developments in nuclear reaction theories and calculations

Description: A brief review is given of some recent developments in the fields of optical model potentials; level densities; and statistical model, precompound, and direct reaction codes and calculations. Significant developments have occurred in all of these fields since the 1977 Conference on Neutron Cross Sections, which will greatly enhance the ability to calculate high-energy neutron-induced reaction cross sections in the next few years. 11 figures, 3 tables.
Date: May 5, 1980
Creator: Gardner, D. G.
Partner: UNT Libraries Government Documents Department
open access

Low-temperature hydrothermal resource evaluation

Description: The objectives of testing low-temperature hydrothermal wells are to characterize well response to production (injection), determine resource characteristics and project reservoir longevity. Testing procedures and analysis techniques differ in some respects from proven procedures in the oil and gas and ground water fields. Some basic definitions and standard techniques necessary for the evaluation of a fluid resource in an intergranular permeable reservoir are presented. Problems particular to a… more
Date: May 5, 1980
Creator: Goldman, D.
Partner: UNT Libraries Government Documents Department
open access

Nickel--chromium strain gages for cryogenic stress analysis of superconducting structures in high magnetic fields

Description: Evaluation and calibration measurements were performed on commercial nickel-chromium metal-foil strain gages in a high-magnetic-field (12 T), liquid-helium (4.2 K) environment. The purpose was to fully characterize strain gages for use at cryogenic temperatures in high magnetic fields. In this study, the magnetoresistance of a number of strain gages was measured in three orthogonal directions at mechanical strain levels to 8900 ..mu..m/m. As a result, a unique calibration curve was defined for … more
Date: October 5, 1977
Creator: Freynik, H.S. Jr.; Roach, D.R.; Deis, D.W. & Hirzel, D.G.
Partner: UNT Libraries Government Documents Department
open access

Testing of the MFTF magnets

Description: This paper describes the cooldown and testing of the first yin-yang magnet for the Mirror Fusion Test Facility. The introduction describes the superconducting magnet; the rest of the paper explains the tests prior to and including magnet cooldown and final acceptance testing. The MFTF (originally MX) was proposed in 1976 and the project was funded for construction start in October 1977. Construction of the first large superconducting magnet set was completed in May 1981 and testing started shor… more
Date: May 5, 1982
Creator: Kozman, T.A.; Chang, Y. & Dalder, E.N.C.
Partner: UNT Libraries Government Documents Department
open access

Technology development for high-salinity geothermal resources

Description: An impulse turbine for Total Flow utilization of geothermal fluids was tested. Performance measurements verify the calculational model. The research goal of 70% engine efficiency remains credible. Addition of acid to the brine prevents scaling and precipitation at moderate costs. Corrosion and erosion of turbine materials for the Total Flow Process are not severe. (JB)
Date: August 5, 1977
Creator: Lundberg, A.W.
Partner: UNT Libraries Government Documents Department
open access

National Science Foundation Grants; Young Scholars Projects for High Ability and High Potential Secondary School Students; Guidelines for Proposal Submission

Description: Article in the Federal Register, concerning Young Scholars projects, including project development, project environment, project design, activities, the selection of participants, participant costs, project staff, projects site, eligible organizations, budget, proposal preparation and submission, evaluation and selection of proposals, awards, grant administrations, inquiries, program assessment activities, and SST projects.
Date: July 5, 1987
Partner: Texas Academy of Mathematics and Science
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Effects of doping on hybridization gapped materials

Description: Doping studies are presented on three materials exhibiting hybridization gaps: Ce{sub 3}Bi{sub 4}Pt{sub 3}, U{sub 3}Sb{sub 4}Pt{sub 3}, and CeRhSb. In the case of trivalent La, Y, or Lu substituting for Ce or U, there is a suppression of the low temperature gap and an increase in the electronic specific heat, {gamma}. In the case of tetravalent Th substitutions for U there is no change in {gamma} and in the case of tetravalent Zr substitution for Ce in CeRhSb, there is an enhanced semiconductor… more
Date: June 5, 1991
Creator: Canfield, P. C.; Thompson, J. D.; Hundley, M. F.; Lacerda, A. & Fisk, Z.
Partner: UNT Libraries Government Documents Department
open access

Strain-critical current data for large multifilament Nb/sub 3/Sn conductors

Description: Strain-critical current measurements of monolithic, multifilament Nb/sub 3/Sn conductors are extended to larger conductors carrying approximately 3.5 kA at 12 T. Measurements were made under pure tension up to 0.9 percent strain and under combined tensile (up to 0.36 percent) and bending (+-0.53 percent) strain. Our results came close to those obtained previously on smaller (1 to 2 kA) conductors. These latest data served as our basis to design a prototype 5-kA, 12-T conductor for a 40-cm-bore … more
Date: October 5, 1977
Creator: Deis, D.W.; Cornish, D.N.; Hirzel, D.G. & Rosdahl, A.R.
Partner: UNT Libraries Government Documents Department
open access

New Evidence From Soudan 1 for Underground Muons Associated With Cygnus X-3

Description: The Soudan 1 experiment has obtained additional evidence for underground muons associated with the x-ray pulsar Cygnus X-3. We report the preliminary analysis of data recorded during the October 1985 radio outburst of Cygnus X-3, which show a significant excess of muons for a narrow range of Cygnus X-3 phases.
Date: June 5, 1986
Creator: Ayres, D. S.
Partner: UNT Libraries Government Documents Department
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