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Cause of pitting in beryllium

Description: Light microscopy, bare-film radiography, secondary ion mass spectroscopy, electron microprobe and physical testing were used to examine beryllium specimens exhibiting a stratified, pitted, pattern after chemical milling. The objective was to find the cause of this pattern. Specimens were found to have voids in excess of density specification allowances. These voids are attributed, at least in part, to the sublimation of beryllium fluoride during the vacuum hot pressing operation. The origin of … more
Date: April 16, 1982
Creator: Kershaw, R. P.
Partner: UNT Libraries Government Documents Department
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Bumps and poles in the S-matrix: A systematic study of 0 sup ++ and 2 sup ++ mesons plus a molecule approach to the E(1420) in the K K. pi. system

Description: The goal of Hadron Spectroscopy is to find the spectrum of states formed by color singlet arrangements of quarks and gluons. Ideally these spectral states are associated with poles of the scattering matrix of hadrons which are the decay channels of the states. For example the {rho} meson is the lowest q{bar q} s-wave, spin one color singlet state and decays into {pi}{sup +}{pi}{sup -}. Since the {rho}decays in a relative p-wave, one finds the {rho} pole in the I = 1 p-wave {pi}{pi} phase shifts… more
Date: November 16, 1989
Creator: Longacre, R. S.
Partner: UNT Libraries Government Documents Department
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Introduction to albedo neutron dosimeters

Description: The design, operation, calibration, and performance of albedo neutron dosimeters are discussed. An albedo neutron dosimeter is designed to measure the flux of thermal neutrons which leave the body when a person is exposed to fast energy neutrons. The fast neutrons are scattered and moderated in the body, and many have lost most of their initial energy and emerge as thermal neutrons. The albedo neutron dosimeter is designed to detect this flux of thermal neutrons by using a thermal neutron detec… more
Date: January 16, 1978
Creator: Hankins, D.E.
Partner: UNT Libraries Government Documents Department
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Universal formula for the quasistatic second-order density perturbation by a cold magnetoplasma wave

Description: Using the general expression for the ponderomotive Hamiltonian, the quasi-static quasi-neutral density change caused by the ponderomotive force of a cold magnetoplasma wave of arbitrary frequency and polarization is obtained. This formula agrees with and extends previous results for unmagnetized and magnetized plasma.
Date: December 16, 1977
Creator: Kaufman, A. N.; Cary, J. R. & Pereira, N. R.
Partner: UNT Libraries Government Documents Department
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RODCON: a finite difference heat conduction computer code in cylindrical coordinates

Description: RODCON, a finite difference computer code, was developed to calculate the internal temperature distribution of the fuel rod simulator (FRS) for the Core Flow Test Loop (CFTL). RODCON solves the implicit, time-dependent forward-differencing heat transfer equation in 2-dimensional (Rtheta) cylindrical coordinates at an axial plane with user specified radial material zones and surface conditions at the FRS periphery. Symmetry of the boundary conditions of coolant bulk temperatures and film coeffic… more
Date: September 16, 1980
Creator: Conklin, J. C.
Partner: UNT Libraries Government Documents Department
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Probing the possibility of a /sup 12/C/sup 13/C abundance gradient from observations of interstellar CH/sup +/

Description: I have performed high signal-to-noise (SN /equals/ 300 to 500) observations of interstellar CH/sup /plus// at Lick Observatory and at CTIO of the reddened, early-type stars HD 183143, HD 24432, and HD 157038 in an effort to probe the existence of a /sup 12/C/sup 13/C abundance gradient in our Galaxy.
Date: September 16, 1987
Creator: Hawkins, I.
Partner: UNT Libraries Government Documents Department
open access

Small Angle Physics at CDF: A Progress Report

Description: In 1989 CDF collected data in special high beta runs with a trigger selecting elastic and inelastic events in order to measure the total cross section ({sigma}{sub tot}) and the differential elastic cross section (d{sigma}{sub el}/dt). Data were taken at cms energies of 300, 540, 1000 and 1800 GeV. A double arm magnetic spectrometer located along the beam pipe tags the particles scattered at very small angles and tracking detectors surrounding the interaction point reveal particles produced at … more
Date: December 16, 1989
Creator: Paoletti, Riccardo
Partner: UNT Libraries Government Documents Department
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Hydrogenation of CO and CO/sub 2/ on clean rhodium and iron foils. Correlations of reactivities and surface compositions

Description: An experimental arrangement consisting of an ultrahigh vacuum bell jar equipped with an internal sample isolation cell was used to investigate the hydrogenation of CO over Fe and Rh surfaces. This apparatus permitted both UHV surface characterization (Auger electron spectroscopy, low-energy electron diffraction) and high pressure (1-20 atm) catalytic reactions to be carried out. Small surface area (approximately 1 cm/sup 2/) metal samples, both single crystals and polycrystalline foils, were us… more
Date: December 16, 1977
Creator: Dwyer, D.; Yoshida, K. & Somorjai, G.A.
Partner: UNT Libraries Government Documents Department
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Secondary recovery of plutonium and americium from process waste streams by solvent extraction

Description: A solvent extraction process is being evaluated for the secondary recovery of plutonium and americium from Rocky Flats waste streams. The bidentate organophosphorus compounds dihexyl-N,N-diethylcarbamylmethylene phosphonate and its dibutyl analogue have been shown to be selective extractants for the actinides from solutions of nitric acid. The results from laboratory test runs in which the organophosphorus extractants were used for processing secondary waste solutions will be presented. Solvent… more
Date: January 16, 1978
Creator: Hagan, P. G. & Navratil, J. D.
Partner: UNT Libraries Government Documents Department
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Comparative analysis of internal fuel motion in annular fuel designs

Description: In this paper, the whole-core reactivity consequences of internal fuel motion in three annular fuel designs during a hypothetical 3 dollars/s transient overpower (TOP) accident are compared to determine the effect of geometric design variations. The PINEX-2 and PINEX-3 experiments were performed in the TREAT reactor using annular fuel pins irradiated in GETR. This paper investigates three combinations of solid and annular axial blankets and fission gas plena: top annular blanket and plenum, bot… more
Date: September 16, 1983
Creator: Smith, D. E.
Partner: UNT Libraries Government Documents Department
open access

An IFE development strategy

Description: The development of inertial fusion as a power source will require achieving four principal milestones: ignition and propagating burn; high gain at low drive energy for the reactor driver; pulse repetition rates of a few Hz; and long-term reliability and economics of a reactor. To keep development time and costs to a minimum, these should be accomplished with as few major facilities as possible. A viable scenario for the Inertial Fusion Energy (IFE) Program would include establishing the first m… more
Date: July 16, 1991
Creator: Hogan, W.J.; Storm, E. & Lindl, J.D.
Partner: UNT Libraries Government Documents Department
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New concept for a high-power beam dump

Description: A new concept for a dump for the ion and neutral beams used in the controlled nuclear fusion program uses thin sheets of a refractory metal such as tungsten formed into troughs having semi-circular cross sections. High-velocity water flowing circumferentially removes heat by subcooled nucleate boiling. Possible advantages are modular construction, lower water-pumping power, and a lower pressure drop than in conventional beam dumps. An example design calculation is shown for a dump capable of ab… more
Date: April 16, 1980
Creator: Moir, R.W. & Taylor, C.E.
Partner: UNT Libraries Government Documents Department
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Magnetic shielding tests for MFTF-B neutral beamlines

Description: A test program to determine the effectiveness of various magnetic shielding designs for MFTF-B beamlines was established at Lawrence Livermore National Laboratory (LLNL). The proposed one-tenth-scale shielding-design models were tested in a uniform field produced by a Helmholtz coil pair. A similar technique was used for the MFTF source-injector assemblies, and the model test results were confirmed during the Technology Demonstration in 1982. The results of these tests on shielding designs for … more
Date: November 16, 1983
Creator: Kerns, J.; Fabyan, J.; Wood, R. & Koger, P.
Partner: UNT Libraries Government Documents Department
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Etiology of contaminated wounds

Description: The US Department of Energy reports of events that occurred in the chemical processing 200 Areas of the Hanford Site during the period from 1972 through 1986 were reviewed to identify the causes of contaminated wounds. Contaminated wounds were reported in 19 events involving 20 workers. The causal agents (high risk operations) and the root causes were characterized. Emergency actions taken and their efficacy were noted. The 19 wound events were compared with 17 events with the potential for inh… more
Date: January 16, 1992
Creator: Sudmann, R.H.
Partner: UNT Libraries Government Documents Department
open access

Richtmyer-Meshkov instabilities in stratified fluids

Description: We present an analytic theory of Richtmyer-Meshkov instabilities in an arbitrary number N of stratified fluids subjected to a shock. Following our earlier work on Rayleigh-Taylor instabilities, the theory assumes incompressible flow in which a shock is treated an impulsive acceleration, g = ..delta.. v delta(tau/sub s), ..delta..v being the jump velocity induced in the system by a shock at time tau/sub s/. We discuss the special cases N = 2 and N = 3, and illustrate both Rayleigh-Taylor and Ric… more
Date: December 16, 1983
Creator: Mikaelian, K.O.
Partner: UNT Libraries Government Documents Department
open access

Acceleration of compact torus plasma rings in a coaxial rail-gun

Description: We discuss here theoretical studies of magnetic acceleration of Compact Torus plasma rings in a coaxial, rail-gun accelerator. The rings are formed using a magnetized coaxial plasma gun and are accelerated by injection of B/sub theta/ flux from an accelerator bank. After acceleration, the rings enter a focusing cone where the ring is decelerated and reduced in radius. As the ring radius decreases, the ring magnetic energy increases until it equals the entering kinetic energy and the ring stagna… more
Date: May 16, 1985
Creator: Hartman, C. W.; Hammer, J. H. & Eddleman, J.
Partner: UNT Libraries Government Documents Department
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Management of solid waste

Description: Compliance with the latest regulatory requirements addressing disposal of radioactive, hazardous, and sanitary solid waste requires the application of numerous qualitative and quantitative criteria in the selection, design, and operation of solid waste management facilities. Due to the state of flux of these regulatory requirements from EPA and NRC, several waste management options were identified as being applicable to the management of the various types of solid waste. This paper highlights t… more
Date: April 16, 1980
Creator: Thompson, W.T. & Stinton, L.H.
Partner: UNT Libraries Government Documents Department
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Inspection methods for safeguards systems at nuclear facilities

Description: A project team at Lawrence Livermore National Laboratory has been developing inspection procedures and training materials for the NRC inspectors of safeguards systems at licensed nuclear facilities. This paper describes (1) procedures developed for inspecting for compliance with the Code of Federal Regulations, (2) training materials for safeguards inspectors on technical topics related to safeguards systems, such as computer surety, alarm systems, sampling techniques, and power supplies, and (… more
Date: October 16, 1981
Creator: Minichino, C. & Richard, E.W.
Partner: UNT Libraries Government Documents Department
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Three wavelength optical alignment of the Nova laser

Description: The Nova laser, presently under construction at Lawrence Livermore National Laboratory, will be capable of delivering more than 100 kJ of focused energy to an Inertial Confinement Fusion (ICF) target. Operation at the fundamental wavelength of the laser (1.05 ..mu..m) and at the second and third harmonic will be possible. This paper will discuss the optical alignment systems and techniques being implemented to align the laser output to the target at these wavelengths prior to each target irradi… more
Date: November 16, 1983
Creator: Swift, C. D.; Bliss, E. S.; Jones, W. A. & Seppala, L. G.
Partner: UNT Libraries Government Documents Department
open access

Implicit methods in particle simulation

Description: This paper surveys recent advances in the application of implicit integration schemes to particle simulation of plasmas. The use of implicit integration schemes is motivated by the goal of efficiently studying low-frequency plasma phenomena using a large timestep, while retaining accuracy and kinetics. Implicit schemes achieve numerical stability and provide selective damping of unwanted high-frequency waves. This paper reviews the implicit moment and direct implicit methods. Lastly, the mergin… more
Date: March 16, 1982
Creator: Cohen, B.I.
Partner: UNT Libraries Government Documents Department
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Electroweak symmetry breaking: Higgs/whatever

Description: In the first of these two lectures the Higgs mechanism is reviewed in its most general form, which does not necessarily require the existence of Higgs bosons. The general consequences of the hypothesis that electroweak symmetry breaking is due to the Higgs mechanism are deduced just from gauge invariance and unitarity. In the second lecture the general properties are illustrated with three specific models: the Weinberg-Salam model, its minimal supersymmetric extension, and technicolor. The seco… more
Date: October 16, 1989
Creator: Chanowitz, Michael S.
Partner: UNT Libraries Government Documents Department
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Risk assessment and radioactive waste management

Description: Problems associated with radioactive waste management, both technological and administrative, have become a serious constraint in the development of nuclear power. An approach toward understanding these problems consists of placing them in a perspective where the risks of radioactive waste management might be evaluated in relation to similar problems facing society so that consistent judgments can be made.
Date: August 16, 1977
Creator: Cohen, J.J.
Partner: UNT Libraries Government Documents Department
open access

First-principles analysis of electron-phonon interactions in graphene

Description: Article on first-principles analysis of electron-phonon interactions in graphene.
Date: March 16, 2010
Creator: Borysenko, Kostyantyn M.; Mullen, Jeffrey T.; Barry, E. A.; Paul, S.; Semenov, Yuriy G.; Zavada, J. M. et al.
Partner: UNT College of Arts and Sciences
open access

Projections of transport scaling laws for small toroidal reactors

Description: Transport in present day Spheromaks is dominated by impurity radiation. Fortunately, this is largely from oxygen and carbon, not metal vapor from the walls of the vessel on plasma guns and it is expected this loss can be eliminated by improved technique. The formation and gross MHD stability properties of these plasmas are quite well understood and so the reactor predictions depend on estimates of the energy loss rates from the plasma. In the absence of significant experimental data one is driv… more
Date: November 16, 1981
Creator: McNamara, B.
Partner: UNT Libraries Government Documents Department
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