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Comment on a Generalized Corresponding-States Method for the Prediction of Surface Tension of Pure Liquids and Liquid Mixtures (open access)

Comment on a Generalized Corresponding-States Method for the Prediction of Surface Tension of Pure Liquids and Liquid Mixtures

This article provides comments on "Generalized corresponding-states method for the prediction of surface tension of pure liquids and liquid mixtures," published in the 'Journal of Colloid and Interface Science' in 1982.
Date: September 1, 1983
Creator: Acree, William E. (William Eugene)
System: The UNT Digital Library
Gordon Conference on Nuclear Research (open access)

Gordon Conference on Nuclear Research

Session topics were: quarks and nuclear physics; anomalons and anti-protons; the independent particle structure of nuclei; relativistic descriptions of nuclear structure and scattering; nuclear structure at high excitation; advances in nuclear astrophysics; properties of nuclear material; the earliest moments of the universe; and pions and spin excitations in nuclei.
Date: September 1983
Creator: Austin, S. M.
System: The UNT Digital Library
Thermal problems on high flux beam lines (open access)

Thermal problems on high flux beam lines

Wiggler and undulator magnets can provide very intense photon flux densities to beam line components. This paper addresses some thermal/materials consequences due to such impingement. The LBL/Exxon/SSRL hybrid-wiggler Beam Line VI now nearing operation will be able to provide up to approx. 7 kW of total photon power at planned SPEAR operating conditions. The first masks are located at 6.5 meters from the source and may receive a peak power density (transverse to the beam) exceeding 20 kW/cm/sup 2/. Significantly, this heat transfer rate exceeds that radiated from the sun's surface (7 kW/cm/sup 2/) and is comparable to that of welding torches. Clearing, cooling and configuration are of critical importance. Configurations for the first fixed mask, the movable mask, and the pivot mask on this beam line are presented together with considerations of thermal stress fatigue and of heat transfer by conduction to water-cooling circuits. Some preliminary information on heating of crystals and mirrors is also presented.
Date: September 1, 1983
Creator: Avery, R.T.
System: The UNT Digital Library
Sensitivity and uncertainty investigations for Hiroshima dose estimates and the applicability of the Little Boy mockup measurements (open access)

Sensitivity and uncertainty investigations for Hiroshima dose estimates and the applicability of the Little Boy mockup measurements

This paper describes sources of uncertainty in the data used for calculating dose estimates for the Hiroshima explosion and details a methodology for systematically obtaining best estimates and reduced uncertainties for the radiation doses received. (ACR)
Date: September 13, 1983
Creator: Bartine, D. E. & Cacuci, D. G.
System: The UNT Digital Library
Angle-Resolved Photoemission Extended Fine Structure (open access)

Angle-Resolved Photoemission Extended Fine Structure

Core level angle-resolved photoemission intensity oscillates sinusoidally with increasing photoelectron momentum. Interference between direct and scattered photo-emission causes this angle-resolved photoemission extended fine structure (ARPEFS). We will discuss an analytic single-scattering theory which quantitatively describes the oscillations. The procedures for extracting surface geometry information from photoemission measurements will be illustrated with S(1s) ARPEFS from S on Ni(100) and Cu(100) obtained with the soft X-ray double crystal monochromator at the Stanford Synchrotron Radiation Laboratory. Building on the surface sensitivity and chemical selectivity of photoemission, ARPEFS analysis provides direct geometrical information from the oscillation frequencies (derived with auto-regressive Fourier analysis), from intensity changes with polarization and analyzer position, and from analysis of scattering phase-shift zero-crossings.
Date: September 1983
Creator: Barton, J. J.; Bahr, C. C.; Hussain, Z.; Robey, S. W.; Klebanoff, L. E. & Shirley, D. A.
System: The UNT Digital Library
Evaluation of Nuclear Facility Decommissioning Projects program (open access)

Evaluation of Nuclear Facility Decommissioning Projects program

The objective of the Evaluation of Nuclear Facility Decommissioning Projects (ENFDP) program is to provide the NRC licensing staff with data which will allow an assessment of radiation exposure during decommissioning and the implementation of ALARA techniques. The data will also provide information to determine the funding level necessary to ensure timely and safe decommissioning operations. Actual decommissioning costs, methods and radiation exposures are compared with those estimated by the Battelle-PNL and ORNL NUREGs on decommissioning. Exposure reduction techniques applied to decommissioning activities to meet ALARA objectives are described. The lessons learned concerning various decommissioning methods are evaluated.
Date: September 9, 1983
Creator: Baumann, B. L.
System: The UNT Digital Library
Factorization and other novel effects in QCD (open access)

Factorization and other novel effects in QCD

Recent progress in proving the validity of factorization for inclusive reactions in QCD is reviewed. A new necessary condition involving the target length is emphasized. We also discuss a number of novel effects in gauge theory including null zone phenomena, color transparency, formation zone conditions, and possible heavy quark Fock states components in ordinary hadrons. 36 references.
Date: September 1, 1983
Creator: Brodsky, Stanley J.
System: The UNT Digital Library
Beam dynamics in the Advanced Test Accelerator (ATA) (open access)

Beam dynamics in the Advanced Test Accelerator (ATA)

We will review the performance of the Advanced Test Accelerator, a 50 MeV, 10 KA induction linac. The discussion will cover the operation of the plasma cathode electron source, beam transport throughout the accelerator, and transverse instabilities. Particular emphasis will be placed on the beam breakup instability and on the methods used to minimize it. These include a program of design changes that lead to an order of magnitude reduction in the Q's of the accelerator cavity modes and optimization of the transport tune.
Date: September 28, 1983
Creator: Caporaso, G. J.; Barletta, W. A.; Birx, D. L.; Briggs, R. J.; Chong, Y. P.; Cole, A. G. et al.
System: The UNT Digital Library
Problems in astrophysical radiation hydrodynamics (open access)

Problems in astrophysical radiation hydrodynamics

The basic equations of radiation hydrodynamics are discussed in the regime that the radiation is dynamically as well as thermally important. Particular attention is paid to the question of what constitutes an acceptable approximate non-relativistic system of dynamical equations for matter and radiation in this regime. Further discussion is devoted to two classes of application of these ideas. The first class consists of problems dominated by line radiation, which is sensitive to the velocity field through the Doppler effect. The second class is of problems in which the advection of radiation by moving matter dominates radiation diffusion.
Date: September 14, 1983
Creator: Castor, John I.
System: The UNT Digital Library
Calculation of polarization effects (open access)

Calculation of polarization effects

Basically there are two areas of accelerator applications that involve beam polarization. One is the acceleration of a polarized beam (most likely a proton beam) in a synchrotron. Another concerns polarized beams in an electron storage ring. In both areas, numerical techniques have been very useful.
Date: September 1, 1983
Creator: Chao, A.W.
System: The UNT Digital Library
Time-resolved beam-profile measurements on the Experimental Test Accelerator (ETA) (open access)

Time-resolved beam-profile measurements on the Experimental Test Accelerator (ETA)

Examples are given of time-resolved beam profiles measured on ETA using several techniques. One method uses a Faraday cup that is remotely movable in two-transverse dimensions (x, y). In another method a small diameter wire or pellet target is moved across the beam and the bremsstrahlung x-ray intensity is plotted. Data for these methods are recorded using a Tektronix 7912 digitizer at 16 equally spaced times during 50 ns. Three other methods use a time gated (4 ns) microchannel plate television camera to record a two-dimensional image of the beam intensity on a single pulse. The light sources used for imaging are: Cherenkov light from a Kapton foil, prompt visible light from a titanium foil and radiated light from gas molecules excited by the beam. We are also testing an x-ray pinhole camera using K/sub ..cap alpha../ x-rays from tungsten.
Date: September 22, 1983
Creator: Chong, Y. P.; Lauer, E. J.; Clark, J. C.; Slaughter, D. R. & Fessenden, T. J.
System: The UNT Digital Library
Influence of a flowing-lithium environment on the fatigue and tensile properties of Type 316 stainless steel (open access)

Influence of a flowing-lithium environment on the fatigue and tensile properties of Type 316 stainless steel

Low-cycle fatigue and tensile data have been obtained on Type 316 stainless steel in a flowing lithium environment of controlled purity. The results show that the fatigue life of the steel in flowing lithium at 755 K is greater than in air. Preexposure of the material to lithium reduces fatigue life. The reduction in fatigue life may be attributed to the formation of a weak ferrite layer after lithium exposure. Tensile data for cold-worked Type 316 stainless steel indicate that at temperatures between 476 and 755 K, a flowing lithium environment has little or no effect on the tensile properties of the steel.
Date: September 1, 1983
Creator: Chopra, O. K. & Smith, D. L.
System: The UNT Digital Library
TMX-U diagnostic system (open access)

TMX-U diagnostic system

Using data from the TMX-U diagnostic system, the production of sloshing ions has already been verified and the formation of electron thermal barriers is presently being investigated on the Tandem Mirror Experiment-Upgrade (TMX-U) at Lawrence Livermore National Laboratory. The TMX-U diagnostics are made up of the earlier TMX complement of diagnostics that determine confinement, microstability, and low-frequency stability, plus diagnostic instrumentation that measures electron parameters associated with mirror-confined electrons. This paper describes the three subsystems within the TMX-U diagnostic system: (1) the diagnostic facility (shot leader console, data cable system, and diagnostic timing system); (2) the individual diagnostic instruments that measure plasma and machine parameters; and (3) the data-acquisition and -analysis computer.
Date: September 2, 1983
Creator: Correll, D.L.
System: The UNT Digital Library
Issues in radioactivity for fusion energy: remote maintenance rating (open access)

Issues in radioactivity for fusion energy: remote maintenance rating

Recent technical progress in fusion research has been sufficient to encourage the development of conceptual designs for fusion power systems. These design efforts suggest that more attention should be paid to the safety and environmental effects of the radioactivity induced in the structural materials by the fusion neutrons. In particular, radioactivity from neutron activation of the structural components of a fusion power system will be a concern for occupational exposure of personnel. Careful choice of structural materials can significantly reduce this exposure. We propose the Remote Maintenance Rating (RMR) as a numerical means of comparing materials and machine designs with respect to occupational exposures. The RMR is defined as the dose rate at the surface of a uniformly activated, thick, infinite slab with the same composition and density as the machine component. We used the RMR rating system to evaluate the suitability of several different iron-based alloys. The specific fusion power system design used in our evaluation was a conceptual design from the Mirror Advanced Reactor Study (MARS). We determined that HT-9 is significantly better in terms of radiological dose rates at early times than the other iron-based alloys (by a factor of 3 to 7). We also calculated the …
Date: September 14, 1983
Creator: Dorn, D.W. & Maninger, R.C.
System: The UNT Digital Library
Applying process-control techniques to a research environment: on-line controls and instrumentation for Doublet III fusion project (open access)

Applying process-control techniques to a research environment: on-line controls and instrumentation for Doublet III fusion project

The system design is given in terms of the following: (1) conventional aspects, (2) architecture, (3) electronic interfaces, (4) operator interfaces, (5) unconventional aspects, (6) electrical energy, (7) electrical noise, (8) operating flexibility, and (9) command procedure development. (MOW)
Date: September 1, 1983
Creator: Drobnis, D. D.
System: The UNT Digital Library
First results from MARK III at SPEAR. MARK III collaboration (open access)

First results from MARK III at SPEAR. MARK III collaboration

The MARK III detector, operating at SPEAR, has collected approx. 2.7 x 10/sup 6/ phi decays and 4500 nb/sup -1/ of phi'' decays. Preliminary results from the full phi samples are presented.
Date: September 1, 1983
Creator: Einsweiler, K.F.
System: The UNT Digital Library
Power-amplification of a heavy-ion beam in an induction linac (open access)

Power-amplification of a heavy-ion beam in an induction linac

In contrast to an rf linac - a constant-current device in which the beam power is increased solely by the addition of kinetic energy, qV, - the induction linac (I.L.) can amplify the beam power at a much more rapid rate. Proper programming of the switching of the modules and the shape of their voltage waveforms, in the early stages of acceleration, can result in a beam current that rises at a rate between V/sup 1/2/ and V and, consequently, a beam power that varies in the range V/sup 3/2/ to V/sup 2/. The current is limited by the transport lens system, which must overcome the beam defocusing force due to space charge.
Date: September 1, 1983
Creator: Faltens, A. & Keefe, D.
System: The UNT Digital Library
Power-Amplification of a Heavy-Ion Beam in an InductionLinac (open access)

Power-Amplification of a Heavy-Ion Beam in an InductionLinac

In contrast to an rf linac - a constant-current device in which the beam power is increased solely by the addition of kinetic energy, qV, - the induction linac (I.L.) can amplify the beam power at a much more rapid rate. Proper programming of the switching of the modules and the shape of their voltage waveforms, in the early stages o f acceleration, can result in a beam current that rises at a rate between v{sup 1/2} and V and, consequently, a beam power that varies in the range v{sup 3/2} to v{sup 2}. The current is limited by the transport lens system, which must overcome the beam defocusing force due to space charge.
Date: September 1, 1983
Creator: Faltens, A. & Keefe, D.
System: The UNT Digital Library
Simulation of a high-gain tapered-wiggler free-electron laser (open access)

Simulation of a high-gain tapered-wiggler free-electron laser

We present results from a numerical model of a high-gain (electron-beam power > input laser beam power) FEL amplifier.
Date: September 27, 1983
Creator: Fawley, W. M.; Scharlemann, E. T. & Prosnitz, D.
System: The UNT Digital Library
Vectorizing and machine-spanning techniques (open access)

Vectorizing and machine-spanning techniques

Techniques for vectorizing complex logic are shown using a decoupled sliding-surface calculation that is part of a two-dimensional Lagrangian simulation model. The same source coding can be run on many vector, parallel, and multiprocessor computers with very little or no alteration. The vectorizing techniques have been used for a wide range of problems.
Date: September 22, 1983
Creator: Giroux, E D
System: The UNT Digital Library
Magnetic mirror fusion power systems (open access)

Magnetic mirror fusion power systems

None
Date: September 15, 1983
Creator: Gordon, J. D. & Logan, B. G.
System: The UNT Digital Library
Neutron and gamma-ray measurements on the LANL Little Boy Comet Assembly (open access)

Neutron and gamma-ray measurements on the LANL Little Boy Comet Assembly

We measured the neutron and gamma-ray dose rates at various distances from the Little Boy Comet Assembly at Los Alamos National Laboratory (LANL), Los Alamos, New Mexico on April 28 and 29, 1983. The distances selected varied from 350 ft to 1860 ft from the assembly, with the latter point being located at the edge of the mesa overlooking Pajarito Canyon. We varied the power levels for the various runs but we have normalized all of them to a single power-level. We also made corrections for the variations in the power-level indicators of the assembly using data provided by LANL.
Date: September 1, 1983
Creator: Hankins, D.E.
System: The UNT Digital Library
Transients - abnormal and otherwise (open access)

Transients - abnormal and otherwise

Information is presented concerning transients in research reactors and nuclear power plants.
Date: September 27, 1983
Creator: Hendrie, J. M.
System: The UNT Digital Library
Analytical studies of advanced high-field designs: 20-tesla large-bore superconducting magnets (open access)

Analytical studies of advanced high-field designs: 20-tesla large-bore superconducting magnets

Several emerging technologies have been combined in a conceptual design study demonstrating the feasibility of producing ultrahigh magnetic fields from large-bore superconducting solenoid magnets. Several designs have been produced that approach peak fields of 20-T in 2.0-m diameter inner bores. The analytical expressions comprising the main features of CONDUCTOR and ADVMAGNET, the two computer programs used in the design of these advanced magnets, are also discussed. These magnets and design techniques will make a paramount contribution to the national mirror-fusion endeavor and to the newly emerging field of nuclear magnetic resonance (NMR) whole-body scanners.
Date: September 30, 1983
Creator: Hoard, R. W.; Cornish, D. N.; Scanlan, R. M.; Zbasnik, J. P.; Leber, R. L.; Hickman, R. B. et al.
System: The UNT Digital Library