Computer program SCAP-BR for gamma-ray streaming through multi-legged ducts (open access)

Computer program SCAP-BR for gamma-ray streaming through multi-legged ducts

A computer program, SCAP-BR, has been developed at Burns and Roe for the gamma-ray streaming analysis through multi-legged ducts. SCAP-BR is a modified version of the single scattering code, SCAP, incorporating capabilities of handling multiple scattering and volumetric source geometries. It utilizes the point kernel integration method to calculate both the line-of-sight and scattered gamma dose rates by employing the ray tracing technique through complex shield geometries. The multiple scattering is handled by a repeated process of the single scatter method through each successive scatter region and collapsed pseudo source meshes constructed on the relative coordinate systems. The SCAP-BR results have been compared with experimental data for a Z-type (three-legged) concrete duct with a Co-60 source placed at the duct entrance point. The SCAP-BR dose rate predictions along the duct axis demonstrate an excellent agreement with the measured values.
Date: December 8, 1977
Creator: Byoun, T. Y.; Babel, P. J. & Dajani, A. T.
System: The UNT Digital Library
Effects of energy constraints on transportation systems. [Twenty-six papers] (open access)

Effects of energy constraints on transportation systems. [Twenty-six papers]

Twenty-six papers are presented on a variety of topics including: energy and transportaton facts and figures; long-range planning under energy constraints; technology assessment of alternative fuels; energy efficiency of intercity passenger and freight movement; energy efficiency of intracity passenger movement; federal role; electrification of railroads; energy impact of the electric car in an urban enviroment; research needs and projects in progress--federal viewpoint; research needs in transportation energy conservation--data needs; and energy intensity of various transportation modes--an overview. A separate abstract was prepared for each of the papers for inclusion in Energy Research Abstracts (ERA) and in Energy Abstracts for Policy Analysis (EAPA).
Date: December 1, 1977
Creator: Mittal, R. K.
System: The UNT Digital Library
Universal formula for the quasistatic second-order density perturbation by a cold magnetoplasma wave (open access)

Universal formula for the quasistatic second-order density perturbation by a cold magnetoplasma wave

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.
System: The UNT Digital Library
Explosion potential of neutral-beam source cryopumps for TFTR (open access)

Explosion potential of neutral-beam source cryopumps for TFTR

The explosion potential of the test cryopump became a paramount issue in the safety analysis required for the reactor experiment. The administrative limit for loading of the cryopump with normal hydrogen or deuterium is that amount of gas which will produce a partial pressure of 13 torr at a total pressure of 1 atmosphere, i.e., a 1.7% mixture by volume. At atmospheric pressure, combustion can occur for mixtures in the range 4.0 to 75%. It is important to know whether, in a leak-up-to-air accident, when the partial pressure will range from 100% to 1.7%, an explosion can occur. For the test cryopump (250l), loaded to the administrative limit, the energy of combustion would amount to 9.21 x 10/sup 5/ J, or 21.9 g of T.N.T. equivalent. However, for a TFTR beamline (73,000l), the corresponding numbers are 2.69 x 10/sup 7/ J, or 6.39 x 10/sup 3/ g of T.N.T. equivalent.
Date: December 1, 1977
Creator: Graham, W. G.; Lim, T. H. & Ruby, L.
System: The UNT Digital Library
Linear magnetic fusion: summary of Seattle workshop (open access)

Linear magnetic fusion: summary of Seattle workshop

The linear-geometry magnetic confinement concept is among the oldest used in the study of high-temperature plasmas. However, it has generally been discounted as a suitable approach for demonstrating controlled thermonuclear fusion because rapid losses from the plasma column ends necessitate very long devices. Further, the losses and how to overcome them have not yet received parametric experimental study, nor do facilities exist with which such definitive experiments could be performed. Nonetheless, the important positive attribute, simplicity, together with the appearance of several ideas for reducing end losses have provided motivation for continued research on linear magnetic fusion (LMF). These motivations led to the LMF workshop, held in Seattle, March 9--11, 1977, which explored the potential of LMF as an alternate approach to fusion. A broad range of LMF aspects were addressed, including radial and axial losses, stability and equilibrium, heating, technology, and reactor considerations. The conclusions drawn at the workshop are summarized.
Date: December 1, 1977
Creator: unknown
System: The UNT Digital Library
Hydrogenation of CO and CO/sub 2/ on clean rhodium and iron foils. Correlations of reactivities and surface compositions (open access)

Hydrogenation of CO and CO/sub 2/ on clean rhodium and iron foils. Correlations of reactivities and surface compositions

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 used to catalyze the H/sub 2//CO reaction at high pressures (1-6 atm). Reaction products were monitored with a gas chromatograph equipped with a flame ionization detector. The surface compositions of the metal samples were determined before and after the reaction and the results correlated with the observed product distributions and reaction rates. In addition, the influence of various surface additives (carbon, oxygen, potassium) was also investigated. Iron was the more reactive of the two metals studied and was found to produce C/sub 1/-C/sub 5/ straight chain hydrocarbons but it poisoned rapidly. The catalytically active surface of both metals was covered with a carbonaceous monolayer. The carbonaceous monolayer was stable on the rhodium surface and produced C/sub 1/-C/sub 4/ hydrocarbons at a steady rate even after several hours of reaction. The …
Date: December 16, 1977
Creator: Dwyer, D.; Yoshida, K. & Somorjai, G.A.
System: The UNT Digital Library
Design of the core support and restraint structures for FFTF and CRBRP (open access)

Design of the core support and restraint structures for FFTF and CRBRP

This paper presents and compares the design and fabrication of the FFTF and CRBRP reactor structures which support and restrain the reactor core assemblies. The fabrication of the core support structure (CSS) for the FFTF reactor was completed October 1972 and this paper discusses how the fabrication problems encountered with the FFTF were avoided in the subsequent design of the CRBR CSS. The radial core restraint structure of the FFTF was designed and fabricated such that an active system could replace the present passive system which is segmented and relies on the CSS core barrel for total structure integrity to maintain core geometry. The CRBR core restraint structure is designed for passive restraint only, and this paper discusses how the combined strengths of the restraint structure former rings and the CSS core barrel are utilized to maintain core geometry. Whereas the CSS for the FFTF interfaces directly with the reactor core assemblies, the CRBR CSS does not. A comparison is made on how intermediate structures in CRBR (inlet modules) provide the necessary design interfaces for supporting and providing flow distribution to the reactor core assemblies. A discussion is given on how the CRBR CSS satisfied the design requirements of the …
Date: December 1, 1977
Creator: Sutton, H.G. & Rylatt, J.A.
System: The UNT Digital Library
Effects of a hypothetical loss-of-coolant accident on a Mark I Boiling Water Reactor pressure-suppression system (open access)

Effects of a hypothetical loss-of-coolant accident on a Mark I Boiling Water Reactor pressure-suppression system

A loss-of-coolant accident (LOCA) in a boiling-water-reactor (BWR) power plant has never occurred. However, because this type of accident could be particularly severe, it is used as a principal theoretical basis for design. A series of consistent, versatile, and accurate air-water tests that simulate LOCA conditions has been completed on a /sup 1///sub 5/-scale Mark I BWR pressure-suppression system. Results from these tests are used to quantify the vertical-loading function and to study the associated fluid dynamics phenomena. Detailed histories of vertical loads on the wetwell are shown. In particular, variation of hydrodynamic-generated vertical loads with changes in drywell-pressurization rate, downcomer submergence, and the vent-line loss coefficient are established. Initial drywell overpressure, which partially preclears the downcomers of water, substantially reduces the peak vertical loads. Scaling relationships, developed from dimensional analysis and verified by bench-top experiments, allow the /sup 1///sub 5/-scale results to be applied to a full-scale BWR power plant. This analysis leads to dimensionless groupings that are invariant. These groupings show that, if water is used as the working fluid, the magnitude of the forces in a scaled facility is reduced by the cube of the scale factor and occurs in a time reduced by the square root …
Date: December 22, 1977
Creator: Pitts, J.H. & McCauley, E.W.
System: The UNT Digital Library
Liquid metal requirements for inertial confinement fusion (open access)

Liquid metal requirements for inertial confinement fusion

The lithium waterfall reactor is described as a concept in which liquid lithium serves as the coolant, tritium breeder, and 1st-wall and blanket structure protector. This reactor has emerged as a promising concept that alleviates the major problems associated with inertial confinement fusion systems. It eliminates the first wall problems resulting from x-rays and pellet debris, and minimizes cyclical thermal stresses. Also, the thick falling region of lithium attenuates neutrons to the point where the blanket structure could survive for the lifetime of the power plant at high power densities.
Date: December 1, 1977
Creator: Meier, W. R. & Maniscalco, J. A.
System: The UNT Digital Library
Comparison of methods for the production of neutral beams (open access)

Comparison of methods for the production of neutral beams

The fusion reactor neutral beam program consists principally of development and application of positive ion based systems in the energy range of less than or equal to 120 keV. Reactor studies for both mirrors and tokamaks, and even studies of tokamak research devices beyond TFTR, indicate a need for higher energies and also higher efficiencies than can be obtained by extrapolating positive ion based systems. The relative merits of systems based on positive ions, positive ions with energy recovery, negative ions and negative ions with energy recovery are reviewed. Then the neutral beam system parameters called for by mirror and tokamak design studies are reviewed. It is found that although certain types of reactors require more efficiency than others, increased emphasis on the development of negative ions and direct recovery is prudent in any case, and that there should be a test of ripple assisted injection into a tokamak.
Date: December 1, 1977
Creator: Stewart, L. D.
System: The UNT Digital Library
Waste management strategy for nuclear fusion power systems from a regulatory perspective (open access)

Waste management strategy for nuclear fusion power systems from a regulatory perspective

A waste management strategy for future nuclear fusion power systems is developed using existing regulatory methodology. The first step is the development of a reference fuel cycle. Next, the waste streams from such a facility are identified. Then a waste management system is defined to safely handle and dispose of these wastes. The future regulator must identify the decisions necessary to establish waste management performance criteria. The data base and methodologies necessary to make these decisions must then be developed. Safe management of nuclear fusion wastes is not only a technological challenge, but encompasses significant social, political, and ethical questions as well.
Date: December 6, 1977
Creator: Heckman, R.A.
System: The UNT Digital Library
Fossil energy research meeting (open access)

Fossil energy research meeting

U.S. ERDA's research programs in fossil energy are reviewed with brief descriptions, budgets, etc. Of general interest are discussions related to the capabilities for such research of national laboratories, universities, energy centers, etc. Of necessity many items are treated briefly, but a general overview of the whole program is provided. (LTN)
Date: December 1, 1977
Creator: Kropschot, R. H. & Phillips, G. C.
System: The UNT Digital Library
Materials testing using laser energy deposition (open access)

Materials testing using laser energy deposition

A convenient method for determining the elastic constants of materials has been devised using the energy from a Q-switched neodymium-glass laser. Stress waves are induced in materials having circular rod or rectangular bar geometries by the absorption of energy from the laser. The wave transit times through the material are recorded with a piezoelectric transducer. Both dilatation and shear wave velocities are determined in a single test using an ultrasonic technique and these velocities are used to calculate the elastic constants of the material. A comparison of the constants determined for ten common engineering materials using this method is made with constants derived using the conventional ultrasonic pulse technique and agreement is shown to be about one percent in most cases. Effects of material geometry are discussed and surface damage to the material caused by laser energy absorption is shown.
Date: December 20, 1977
Creator: Wilcox, W.W. & Calder, C.A.
System: The UNT Digital Library
Neutral beam requirements for mirror reactors (open access)

Neutral beam requirements for mirror reactors

The neutral beam requirements for mirror reactors as presently envisioned are 200 keV for the Field Reversed Mirror (FRM) and 1200 keV for the Tandem Mirror (TMR). The hybrid version of the Standard Mirror, FRM and TMR require 100 to 120 keV. Due to the energy dependence of atomic processes, negative ions should produce neutrals more efficiently than positive ions above some energy and below this energy, positive ions are probably more efficient. This energy is probably somewhere between 100 and 150 keV for D/sup 0/, and 150 and 225 for T/sup 0/. Thus we conclude that hybrid reactors can use D/sup +/ ions but all of the fusion reactor designs call for D/sup -/ ions to make the neutral beams. Trends in the energy requirements are discussed. The hardening of neutral beams against neutron and gamma radiation is discussed.
Date: December 1, 1977
Creator: Moir, Ralph W.
System: The UNT Digital Library
Fundamental study of crack initiation and propagation. [Computer model of ductile fracture] (open access)

Fundamental study of crack initiation and propagation. [Computer model of ductile fracture]

Objective is to determine the fracture toughness of A533B-1 steel by computer modeling Charpy V-notch tests. A computer model of ductile fracture was developed that predicts fracture initiation. The model contains a set of material-dependent parameters obtained by computer simulations of small specimen tests. The computer calculations give detailed stress and strain histories up to the time of fracture, which are used to determine the model parameter values. The calibrated fracture model, that correctly predicts fracture initiation (and initiation energy) in the Charpy specimen, may then be used to simulate tests of accepted fracture-toughness specimens and hence obtain fracture toughness. The model parameters were calibrated to predict fracture in four different test specimens: two different notched-tension specimens, a simple tension specimen, and a precracked compact-tension specimen. The model was then used in a computer simulation of the Charpy V-notch specimen to initiate and advance a flat fracture. Results were compared with interrupted Charpy tests. Calibration of the model for two additional heat treatments of A533B-1 steel is in progress.
Date: December 21, 1977
Creator: Norris, D.M. Jr.; Reaugh, J.E.; Moran, B.; Quinones, D.F. & Wilkins, M.L.
System: The UNT Digital Library
Directions for possible upgrades of the Mirror Fusion Test Facility (MFTF) (open access)

Directions for possible upgrades of the Mirror Fusion Test Facility (MFTF)

The Mirror Fusion Test Facility (MFTF) may be upgraded by extending the time of plasma sustenance in an approach to steady-state operation and/or by increasing the neutral-beam injection energy. Some parameter bounds for these upgrades are discussed as they relate to a definition of the required neutral-beam development.
Date: December 20, 1977
Creator: Damm, C. C.; Coensgen, F. H.; Devoto, R. S.; Molvik, A. W.; Porter, G. D.; Shearer, J. W. et al.
System: The UNT Digital Library
Some illustrations of stochasticity (open access)

Some illustrations of stochasticity

A complex, and apparently stochastic, character frequently can be seen to occur in the solutions to simple Hamiltonian problems. Such behavior is of interest, and potentially of importance, to designers of particle accelerators--as well as to workers in other fields of physics and related disciplines. Even a slow development of disorder in the motion of particles in a circular accelerator or storage ring could be troublesome, because a practical design requires the beam particles to remain confined in an orderly manner within a narrow beam tube for literally tens of billions of revolutions. The material presented is primarily the result of computer calculations made to investigate the occurrence of ''stochasticity,'' and is organized in a manner similar to that adopted for presentation at a 1974 accelerator conference.
Date: December 27, 1977
Creator: Laslett, L.J.
System: The UNT Digital Library
Absolute instrumental neutron activation analysis at Lawrence Livermore Laboratory (open access)

Absolute instrumental neutron activation analysis at Lawrence Livermore Laboratory

The Environmental Science Division at Lawrence Livermore Laboratory has in use a system of absolute Instrumental Neutron Activation Analysis (INAA). Basically, absolute INAA is dependent upon the absolute measurement of the disintegration rates of the nuclides produced by neutron capture. From such disintegration rate data, the amount of the target element present in the irradiated sample is calculated by dividing the observed disintegration rate for each nuclide by the expected value for the disintegration rate per microgram of the target element that produced the nuclide. In absolute INAA, the expected value for disintegration rate per microgram is calculated from nuclear parameters and from measured values of both thermal and epithermal neutron fluxes which were present during irradiation. Absolute INAA does not depend on the concurrent irradiation of elemental standards but does depend on the values for thermal and epithermal neutron capture cross-sections for the target nuclides. A description of the analytical method is presented.
Date: December 21, 1977
Creator: Heft, R.E.
System: The UNT Digital Library
Damage history of Argus, a 4TW Nd-glass system (open access)

Damage history of Argus, a 4TW Nd-glass system

Argus is a twin beam, 20 cm output aperture, Nd:glass laser system that has delivered 4TW to a laser fusion target. This performance is based on the concepts that multiple spatial filtering can prevent beam fill factors. Damage to optics due to self focusing and filamentation does not occur on Argus. The only form of damage is induced by broadband radiation from xenon flashlamps interacting with contaminants on or in the Nd:glass. The severity of damage is measured by the fraction of the beam obscured by the damage sites. This averages 0.1% per surface or 0.75% per arm. The amount of damage does not appear to be strongly related to the number of amplifier firings and generally occurs during the first few firings.
Date: December 6, 1977
Creator: Stowers, I.F. & Patton, H.G.
System: The UNT Digital Library
Effect of transport in distribution of radioions and radiolabeled metabolites (open access)

Effect of transport in distribution of radioions and radiolabeled metabolites

The following topics are discussed: route of administration; carrier effects and complexed or ionic tracers; membrane permeability, extracellular and intracellular concentrations; enzyme and hormonal stimulation or depression and the metabolic state; neoplasia and transport; and carrier for radiopharmaceutical binding to membrane or protein sites. Some radioisotopes considered are /sup 99m/Tc, /sup 65/Zn, /sup 62/Zn, /sup 14/C and /sup 111/In. (HLW)
Date: December 22, 1977
Creator: Yano, Y.
System: The UNT Digital Library
Recent results for /sup 58/Ni and /sup 56/Fe at ORELA. [Widths, J,. pi. ]. EVEL WIDTHS; LEVEL WIDTHS; PARITY; SPIN; ANGULAR DISTRIBUTION; FAST NEUTRONS; KEV RANGE 100-1000; MEV RANGE 01-10 (open access)

Recent results for /sup 58/Ni and /sup 56/Fe at ORELA. [Widths, J,. pi. ]. EVEL WIDTHS; LEVEL WIDTHS; PARITY; SPIN; ANGULAR DISTRIBUTION; FAST NEUTRONS; KEV RANGE 100-1000; MEV RANGE 01-10

Transmission and capture data from /sup 58/Ni were analyzed up to 120 keV and are reported. High-resolution scattering measurements for Fe are discussed, and the determination of the J/sup ..pi../ value for most resonances seen in transmission data up to 400 keV is given, including an attempt at evaluation of the resonances of /sup 56/Fe on the basis of recently published data. 4 figures, 3 tables.
Date: December 1, 1977
Creator: Perey, F.G.; Chapman, G.T.; Kinney, W.E. & Perey, C.M.
System: The UNT Digital Library
Positive ion systems: state of the art and ultimate potential (open access)

Positive ion systems: state of the art and ultimate potential

The PLT or ISX-B ion source has been operated at 40-keV, 60-A, and 0.3-sec pulses with H(D) neutral injected power of 750 kW (approximately 1000 kW) on the PLT device. This report gives a brief description of this system and some future plans. (MOW)
Date: December 6, 1977
Creator: Haselton, H.H.
System: The UNT Digital Library
Brain plasticity, memory, and aging: a discussion (open access)

Brain plasticity, memory, and aging: a discussion

It is generally assumed that memory faculties decline with age. A discussion of the relationship of memory and aging and the possibility of retarding the potential decline is hampered by the fact that no satisfactory explanation of memory is available in either molecular or anatomical terms. However, this lack of description of memory does not mean that there is a lack of suggested mechanisms for long-term memory storage. Present theories of memory usually include first, neurophysiological or electrical events, followed by a series of chemical events which ultimately lead to long-lasting anatomical changes in the brain. Evidence is increasing for the biochemical and anatomical plasticity of the nervous system and its importance in the normal functioning of the brain. Modification of this plasticity may be an important factor in senescence. This discussion reports experiments which indicate that protein synthesis and anatomical changes may be involved in long-term memory storage. Environmental influences can produce quantitative differences in brain anatomy and in behavior. In experimental animals, enriched environments lead to more complex anatomical patterns than do colony or impoverished environments. This raises fundamental questions about the adequacy of the isolated animal which is frequently being used as a model for aging research. …
Date: December 1, 1977
Creator: Bennett, E. L. & Rosenzweig, M. R.
System: The UNT Digital Library
Application of proton radiography to medical imaging (open access)

Application of proton radiography to medical imaging

The use of charged particles for radiographic applications has been considered for some time, but progress has been impeded by the cost and availability of suitable accelerators. However, recent developments in technology could overcome these problems. A review is presented of the physical principles leading to an improvement in mass resolution per unit of absorbed dose for charged particle radiography relative to x-ray radiography. The quantitative comparisons between x-ray and proton radiographs presented here confirm this advantage. The implications of proton radiography on cancer detection, as well as future plans for developing a proton tomographic system, are discussed.
Date: December 1, 1977
Creator: Kramer, S. L.; Martin, R. L.; Moffett, D. R. & Colton, E.
System: The UNT Digital Library