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Radio chemistry as a diagnostic in laser fusion experiments

Description: Nuclear chemistry techniques have been employed in an attempt to measure the density of high compression laser fusion targets. Radioactive /sup 28/Al atoms formed in the /sup 28/Si(n,p)/sup 28/Al reaction arising from the interaction of the 14 MeV neutrons with the silicon atoms in the glass microsphere have been counted at Lawrence Livermore Laboratory using a ..beta..-..gamma.. coincidence method. The detection system that is employed allows activities corresponding to 100 aluminum atoms to b… more
Date: November 1, 1977
Creator: Campbell, E.M.; Hicks, H.G.; Mead, W.C.; Glaros, S.S.; Coleman, L.W. & Laird, W.B.
Partner: UNT Libraries Government Documents Department
open access

Anaerobic fermentation of simulated in-situ oil shale retort water

Description: The feasibility of removing soluble organics from oil shale retort water by anaerobic digestion with methane production was experimentally investigated. The following conclusions were made. The retort water studied had to be pretreated to remove toxic and add deficient constituents before it could be successfully treated with the anaerobic fermentation process. Pretreatment included pH adjustment to 7, ammonia reduction, and nutrient addition. A digested sludge from a conventional municipal sew… more
Date: November 1, 1977
Creator: Ossio, E. A.; Fox, J. P.; Thomas, J. F. & Poulson, R. E.
Partner: UNT Libraries Government Documents Department
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Simple scaling model for exploding pusher targets

Description: A simple model has been developed which when normalized by experiment or Lasnex calculations can be used to scale neutron yields for variations in laser input power and pulse length and target radius and wall thickness. The model also illucidates some of the physical processes occurring in this regime of laser fusion experiments. Within certain limitations on incident intensity and target geometry, the model scales with experiments and calculations to within a factor of two over six decades in … more
Date: November 4, 1977
Creator: Storm, E. K.; Larsen, J. T.; Nuckolls, J. H.; Ahlstrom, H. G. & Manes, K. R.
Partner: UNT Libraries Government Documents Department
open access

Numerical methods for laser fusion

Description: The LASNEX computer code was developed to study the many interrelated physical processes important in the effort to achieve laser initiated fusion. It has been used to calculate the results of numerous laser plasma experiments and to design targets and determine desirable laser pulse characteristics for future experiments. Some processes, such as hydrodynamics, are well formulated in fundamental equations and can be solved with high accuracy by sophisticated numerical methods. Other processes, … more
Date: November 3, 1977
Creator: Zimmerman, G.B.
Partner: UNT Libraries Government Documents Department
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Estimates of post-acceleration longitudinal bunch compression

Description: A simple analytic method is developed, based on physical approximations, for treating transient implosive longitudinal compression of bunches of heavy ions in an accelerator system for ignition of inertial-confinement fusion pellet targets. Parametric dependences of attainable compressions and of beam path lengths and times during compression are indicated for ramped pulsed-gap lines, rf systems in storage and accumulator rings, and composite systems, including sections of free drift. It appear… more
Date: November 25, 1977
Creator: Judd, D.L.
Partner: UNT Libraries Government Documents Department
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Heavy ion reactions in the transition region

Description: Evidence is given for a serious and systematic failure of the DWBA to predict the cross sections for single nucleon transfers induced by heavy ions above about 10 MeV/Nucleon beam energies. This is perhaps related to a coherent coupling to an increasing cross section to the quasi-elastic continuum, which also shows an anomalous energy dependence at about the same energy.
Date: November 1, 1977
Creator: Hendrie, D. L.
Partner: UNT Libraries Government Documents Department
open access

Engineering problems of future neutral beam injectors

Description: Because there is no limit to the energy or power that can be delivered by a neutral-beam injector, its use will be restricted by either its cost, size, or reliability. Studies show that these factors can be improved by the injector design, and several examples, taken from mirror reactor studies, are given.
Date: November 23, 1977
Creator: Fink, J.
Partner: UNT Libraries Government Documents Department
open access

Limits to Ductility Set by Plastic Flow Localization

Description: The theory of strain localization is reviewed with reference both to local necking in sheet metal forming processes and to more general three dimensional shear band localizations that sometimes mark the onset of ductile rupture. Both bifurcation behavior and the growth of initial imperfections are considered. In addition to analyses based on classical Mises-like constitutive laws, approaches to localization based on constitutive models that may more accurately model processes of slip and progre… more
Date: November 1, 1977
Creator: Needleman, A. & Rice, J. R.
Partner: UNT Libraries Government Documents Department
open access

Auger study of surface carbon and oxygen on thorium following ion bombardment

Description: The composition of a thorium metal surface has been monitored using Auger electron spectroscopy following Ar/sup +/ bombardment at different temperatures. After extended Ar/sup +/ bombardment, enough contaminated overlayers were removed to expose a surface region containing only thorium, bulk impurities, and imbedded argon. The main impurities, carbon and oxygen, differed in their behavior when the sample was annealed following bombardment. The amount of surface carbon either increased or remai… more
Date: November 17, 1977
Creator: Bastasz, R. & Colmenares, C.
Partner: UNT Libraries Government Documents Department
open access

Charged particle fusion targets. [Energy requirements for inertial confinement fusion]

Description: The power, voltage, energy and other requirements of electron and ion beam fusion targets are reviewed. Single shell, multiple shell and magnetically insulated target designs are discussed. Questions of stability are also considered. In particular, it is shown that ion beam targets are stabilized by an energy spread in the ion beam.
Date: November 9, 1977
Creator: Bangerter, R.O. & Meeker, D.J.
Partner: UNT Libraries Government Documents Department
open access

Cladding creepdown under compression. [BWR; PWR]

Description: Light-water power reactors use Zircaloy tubing as cladding to contain the UO/sub 2/ fuel pellets. In-service operating conditions impose an external hydrostatic force on the cladding, causing it to creep down into eventual contact with the fuel. Knowledge of the rate of such creepdown is of great importance to modelers of fuel element performance. An experimental system was devised for studying creepdown that meets several severe requirements by providing (1) correct stress state, (2) multiple … more
Date: November 9, 1977
Creator: Hobson, D.O.
Partner: UNT Libraries Government Documents Department
open access

Long pulse microsphere experiments at 3 TW

Description: Previous 1.06 ..mu..m laser implosion experiments have explored the parameter space associated with microsphere targets of typically less than 100 psec. Exploding pusher experiments have now been performed using long pulses (100 to 200 psec FWHM), and large diameter (100 to 150 ..mu..m) targets on the 3 TW Argus laser facility. Absorption, transport, implosion and neutron and ..cap alpha.. yield characteristics are discussed and compared with earlier short pulse results. The observed neutron yi… more
Date: November 1, 1977
Creator: Boyle, M. J.; Attwood, D. T. & Brooks, K. M.
Partner: UNT Libraries Government Documents Department
open access

Valve Applications at the SYNTHANE Plant in Mixed Phase Erosive Service

Description: Three different control valves used for depressuring abrasive, high-pressure process streams containing coal fines have been improved by upgrading their trim materials. Original trims were of ceramic or of stainless steel coated with stellite; upgraded trims are tungsten carbide. The new materials have significantly improved valve life. These valves are in operation at the SYNTHANE Pilot Plant, a high BTU coal gasification facility operated for the Department of Energy by the Lummus Company. Th… more
Date: November 1, 1977
Creator: Bailey, Desmond M.; Massa, Adolph W.; Runnels, Oran D.; Strebinger, Peter C. & Lummus, C. E.
Partner: UNT Libraries Government Documents Department
open access

Uranium nitride: a cubic antiferromagnet with anisotropic critical behavior

Description: Highly anisotropic critical scattering associated with the transition at T/sub N/ = 49.5 K to the type-I antiferromagnetic structure has been observed in uranium nitride. The transverse susceptibility is found to be unobservably small. The longitudinal susceptibility diverges at T/sub N/ and its anisotropy shows that the spins within the (001) ferromagnetic sheets of the (001) domain are much more highly correlated than they are with the spins lying in adjacent (001) sheets. The correlation ran… more
Date: November 1, 1977
Creator: Buyers, W. J. L.; Holden, T. M.; Svensson, E. C. & Lander, G. H.
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

High energy electron spectra from 1. 06. mu. m laser produced plasmas

Description: An electron spectrometer has been modified to measure 1.06 ..mu.. laser produced electrons in the 0.2 to 1.0 MeV range and has been used extensively at the LLL Argus laser facility. We observe a strong correlation between laser pulse width and the amplitude of electron spectral emission from imploded D-T filled microspheres.
Date: November 1, 1977
Creator: Tirsell, K.G. & Catron, H.C.
Partner: UNT Libraries Government Documents Department
open access

Neutron diagnostics for laser fusion experiments

Description: Three different neutron diagnostic instruments are used at our laboratory to acquire data for judging the performance of D-T filled laser-fusion targets. Large scintillation detectors and a neutron activation system are used to measure the number of 14-MeV reaction neutrons emitted from a target, and a 45-meter neutron time-of-flight spectrometer is used to determine the fuel ion temperature. At our facilities, the scintillation detectors are used for neutron yields above 10/sup 4/ per shot, an… more
Date: November 1, 1977
Creator: Lerche, R.A.; Coleman, L.W.; Houghton, J.W. & Tirsell, K.G.
Partner: UNT Libraries Government Documents Department
open access

Propagation of a heavy ion beam in gas-filled reactor

Description: A heavy ion beam traversing a gas-filled reactor is stripped of its electrons along its path. The propagation of the stripping beam with possible associated instabilities has been investigated.
Date: November 3, 1977
Creator: Yu, S. S.; Buchanan, H. L.; Chambers, F. W. & Lee, E. P.
Partner: UNT Libraries Government Documents Department
open access

Avalanche localization and its effects in proportional counters

Description: Avalanche development around the anode wire in a gas proportional counter is investigated. In the region of proportional gas amplification, the avalanche is found to be well localized on one side of the anode wire, where the electrons arrive along the field lines from the point of primary ionization. Induced signals on electrodes surrounding the anode wire are used to measure the azimuthal position of the avalanche on the anode wire. Practical applications of the phenomena such as left-right as… more
Date: November 1, 1977
Creator: Fischer, J.; Okuno, H. & Walenta, A.H.
Partner: UNT Libraries Government Documents Department
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Tests and development of duoplasmatron and mutli-aperture heavy ion sources for an RF linac

Description: The goal of the program of ion source development for an rf linac has been to produce currents of up to 100 mA of the heavier gaseous ions such as argon and xenon, of good emittance (.02 ..pi.. cm mr, normalized) and charge state 1/sup +/. Existing facilities and hardware utilized included the 470 kV Bevatron injector, the 750 kV injector for the 50 MeV ESCAR linac, the 80 kV Bevatron test stand, a 20 kV LLL test stand and existing duoplasmatron and CTR sources. A summary of test results is sho… more
Date: November 1, 1977
Creator: Clark, D. J.; Richter, R. M.; Zajec, E.; Brokloff, R. & Osher, J. E.
Partner: UNT Libraries Government Documents Department
open access

Pinhole imaging of laser-produced thermonuclear alpha particles

Description: Results of pinhole images of thermonuclear alpha particles generated by exploding pusher targets in the Argus laser facility are reviewed. Recorded images indicate that the reactions occur within a 25 to 30 micron region with twelve micron resolution for ten micron pinholes and thirty micron resolution for twenty-five micron pinholes. These results are in good agreement with LASNEX computer predictions and are confirmed by Zone Plate imaging of the burn conducted by Natale M. Ceglio at LLL. Pla… more
Date: November 1, 1977
Creator: Brooks, K. M.; Ceglio, N. M.; Slivinsky, V. W.; Ahlstrom, H. G.; Storm, E. K.; Kornblum, H. N. et al.
Partner: UNT Libraries Government Documents Department
open access

Diagnostic tests determining the thermal response of a house

Description: Two different approaches to the determination of the thermal response of buildings are possible: deterministic models and methods based on equivalent thermal parameters (ETP's) of a building. While the former are computer applications of heat transfer theory, the latter consist of data oriented techniques that infer the ETP's of a particular building by multiple correlation of indoor temperature and weather. The ETP method is convenient to provide a rank ordering of different houses by their th… more
Date: November 1, 1977
Creator: Sonderegger, R.
Partner: UNT Libraries Government Documents Department
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