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Compatibility testing of vitrified waste forms (open access)

Compatibility testing of vitrified waste forms

An experimental program to evaluate candidate metals for use in the fabrication of canisters for long-term storage of vitrified radioactive wastes is described. The long-term compatibility of the candidate metal both with the contained vitrified radioactive waste and with the external environments expected in possible final storage locations will be determined. These tests involve heating combinations of waste forms and canister metals in intimate contact for up to 50,000 hr to accelerate any reactions that occur.
Date: March 6, 1978
Creator: Rankin, W.N.
System: The UNT Digital Library
Optimization of a VISAR for measuring flyer-plate velocities (open access)

Optimization of a VISAR for measuring flyer-plate velocities

VISAR (Velocity Interferometer System for Any Reflector) is commonly used for measuring flyer-plate velocities up to 6 km/s. Flyer plates can travel as much as 1 mm, which is large compared to usual depth-of-focus requirements for VISARs. Flyer plates are explosively driven, or driven by some other very energetic means; as such, they must be tested in a chamber, which will contain the explosion. Routing the laser beam to the chamber and the signal beam to the VISAR can be done safely and easily in multi-mode optical fibers. We have optimized a fiber-coupled VISAR system for measuring flyer-plate velocities. This system given constant signal levels over the full travel of the flyer plate. Furthermore, the signal-collection efficiency is maximized, which allows use of a moderately sized laser. We also have optimized the VISAR cavity so it does not limit the system efficiency while giving a velocity sensitivity of about 1 km/s per fringe. 5 refs.
Date: May 6, 1992
Creator: Sweatt, W. C.; Crump, O. B., Jr. & Brigham, W. P.
System: The UNT Digital Library
Beryllium usage in fusion blankets and beryllium data needs. [None] (open access)

Beryllium usage in fusion blankets and beryllium data needs. [None]

Increasing numbers of designers are choosing beryllium for fusion reactor blankets because it, among all nonfissile materials, produces the highest number (2.5 neutron in an infinite media) of neutrons per 14-MeV incident neutron. In amounts of about 20 cm of equivalent solid density, it can be used to produce fissile material, to breed all the tritium consumed in ITER from outboard blankets only, and in designs to produce Co-60. The problem is that predictions of neutron multiplication in beryllium are off by some 10 to 20% and appear to be on the high side, which means that better multiplication measurements and numerical methods are needed. The n,2n reactions result in two helium atoms, which cause radiation damage in the form of hardening at low temperatures (<300/degree/C) and swelling at high temperatures (>300/degree/C). The usual way beryllium parts are made is by hot pressing the powder. A lower cost method is to cold press and then sinter. There is no radiation damage data on this form of beryllium. The issues of corrosion, safety relative to the release of the tritium built-up inside beryllium, and recycle of used beryllium are also discussed. 10 figs.
Date: April 6, 1988
Creator: Moir, Ralph W.
System: The UNT Digital Library
High-temperature borate liquids: physical properties of glass-forming compositions (open access)

High-temperature borate liquids: physical properties of glass-forming compositions

Several experimental routes can be used to develop a better understanding of the polymeric constitution (polyanionic and/or polyhedral distribution) of borate, germanate, and silicate glasses. Spectral, chemical, physical-chemical, and mechanical property information can be determined directly for the glass compositions of interest. Generally, only physical-chemical information is readily accessible for the corresponding high temperature liquids. It will be shown that information on each state of matter has its own particular merits. Most of the evidence thus far published suggests an excellent agreement between polyhedral distributions in an oxide glass and its corresponding high temperature liquid state. There is no well known oxide glass forming system for which such a state of affairs does not exist. In spite of this, occasional efforts are put forth which ignore some of what is known for oxide liquids, glasses, and crystals. Such attempts therefore invariably imply, if only indirectly, that significant changes occur in the polyhedral distributions close to the glass transition temperature region. Specific examples to be discussed will include efforts that avoid well known coordination change equilibria such as BO/sub 3/ reversible BO/sub 4/ and GeO/sub 4/ reversible GeO/sub 6/.
Date: May 6, 1977
Creator: Riebling, E.F.
System: The UNT Digital Library
Sources of hot electrons in laser-plasma interaction with emphasis on Raman and turbulence absorption (open access)

Sources of hot electrons in laser-plasma interaction with emphasis on Raman and turbulence absorption

Heating targets with high power lasers results in a sizable fraction of the absorbed energy going into electrons of temperature much greater than thermal which can pre-heat the pellet core and accelerate fast ion blowoff which results in poor momentum transfer and hence poor compression efficiency. The present emphasis is to build lasers of higher frequency, ..omega../sub 0/, which at the same W/cm/sup 2/ results in more absorption into cooler electrons. Two physical reasons are that the laser can propagate to a higher electron density, n, infinity..omega../sub 0//sup 2/ resulting in more collisional inverse bremsstrahlung absorption proportional to n, and because the hot temperatures from some plasma absorption processes increase as the oscillatory velocity of an electron in the laser electric field v/sub 0//c = eE/(m/sub e/..omega../sub 0/). The heated electron temperatures from other plasma processes (Raman for example approx.(m/sub e//2)v/sup 2//sub phase/ and the higher laser frequency helps by increasing the competing collisional absorption and decreasing the Raman gain.
Date: April 6, 1982
Creator: Estabrook, K.; Kruer, W. L.; Phillion, D. W.; Turner, R. E. & Campbell, E. M.
System: The UNT Digital Library
Mechanical structure of the Mirror Hybrid Reactor Power Plant (open access)

Mechanical structure of the Mirror Hybrid Reactor Power Plant

The mechanical structure of the LLL/GA Mirror Hybrid Reactor vessel is briefly discussed. Functional requirements and over-all design considerations leading to selection of a post-tensioned concrete reactor vessel and a modular blanket approach are indicated. Module design life of four years, module replacement, capability and remote fueling are provided by the chosen structural design. (RME)
Date: June 6, 1977
Creator: Culver, D.W. & Neef, W.S.
System: The UNT Digital Library
Workshop on core and sample curation for the National Continental Scientific Drilling Program (open access)

Workshop on core and sample curation for the National Continental Scientific Drilling Program

The Workshop on Core and Sample Curation was held to discuss the best means of handling, distributing, and advertising samples and data collected during a Continental Scientific Drilling Program (CSDP) and to establish better communication between sample curators regarding common problems. It was geneerally agreed that CSDP samples should be handled, on a regional basis, by existing data systems and sample repositories judged to have adequate staff and support. Repository design, sample handling procedures, and sample accounting systems were discussed. Across North America, support for curation of geological samples was varied, but it was strongest within states or regions with well-established energy and mineral industries. A well-supported repository pays for itself through the circulation and preservation of samples and stratigraphic information. A national CSDP must have a well-established curatorial policy and system of regional repositories to circulate information and samples throughout the scientific community. Well-curated samples and data are a national resource with considerable benefits for industry and academia. Attendees agreed to form a Society of Geoscience Curators to maintain communication between curators from private, government, and university repositories and core research laboratories.
Date: May 6, 1981
Creator: Goff, S. & Heiken, G. (eds.)
System: The UNT Digital Library
Nuclear reaction uncertainties in standard and non-standard cosmologies (open access)

Nuclear reaction uncertainties in standard and non-standard cosmologies

We discuss here the uncertainties in the nuclear input data relevant for calculations of standard and non-standard primordial nucleosynthesis. We show how these uncertainties can affect the predictive power of such calculations, and we identify those key nuclear reactions for which improved experimental data on the associated reaction rates is most needed. Such experimental data can lead to more accurate discriminatory tests between the differing primordial nucleosynthesis scenarios. 34 refs., 3 tabs.
Date: October 6, 1989
Creator: Malaney, R.A.
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
Harmonically excited orbital variations (open access)

Harmonically excited orbital variations

Rephrasing the equations of motion for orbital maneuvers in terms of Lagrangian generalized coordinates instead of Newtonian rectangular cartesian coordinates can make certain harmonic terms in the orbital angular momentum vector more readily apparent. In this formulation the equations of motion adopt the form of a damped harmonic oscillator when torques are applied to the orbit in a variationally prescribed manner. The frequencies of the oscillator equation are in some ways unexpected but can nonetheless be exploited through resonant forcing functions to achieve large secular variations in the orbital elements. Two cases are discussed using a circular orbit as the control case: (1) large changes in orbital inclination achieved by harmonic excitation rather than one impulsive velocity change, and (2) periodic and secular changes to the longitude of the ascending node using both stable and unstable excitation strategies. The implications of these equations are also discussed for both artificial satellites and natural satellites. For the former, two utilitarian orbits are suggested, each exploiting a form of harmonic excitation. 5 refs.
Date: August 6, 1985
Creator: Morgan, T.
System: The UNT Digital Library
Mechanical design criteria for continuously operating neutral beams (open access)

Mechanical design criteria for continuously operating neutral beams

Mechanical design criteria for high-energy neutral beam injectors capable of prolonged operation are examined. The generalized structural, heat transfer, and hydraulics equations are presented for convectively cooled grids. The effectiveness of helium, liquid sodium, and subcooled water for cooling a 2-mm-diameter, 8-m-long grid tube is shown. Cooling effectiveness is determined as a function of the number of tubes in series vs heat flux, where the number of tubes in series ranges from 1 to 100 and the heat flux ranges from 100 to 10,000 W/cm/sup 2/. The stress analysis of the grid tube walls is presented, enabling data to be added to the heat transfer graphs and giving an upper flux limit for some grid materials. Sputtering is found to be a possible limiting factor for the grid lifetimes. In injectors designed for continuous use, long-term operation without excessive maintenance is required and sputtering must be minimized. To accomplish this, several procedures are proposed.
Date: October 6, 1977
Creator: Vosen, S. R.; Bender, D. J.; Fink, J. H. & Lee, J. D.
System: The UNT Digital Library
Proceedings of the Conference on technology-based confidence building: Energy and environment (open access)

Proceedings of the Conference on technology-based confidence building: Energy and environment

This document contains excerpts from the proceedings of the conference on Technology-based Confidence Building: Energy and the Environment.'' It contains the agenda for the conference and a document on Global Warming and Energy Use;'' a presentation on from Militarism to Environmentalism: a New Focus of US-Soviet Relations;'' a workshop on environmental challenges; a summary address on Science, Technology, and World Affairs;'' an address entitled Energy: the Coin of International Understanding;'' and concluding remarks.
Date: November 6, 1989
Creator: unknown
System: The UNT Digital Library
A universal, fault-tolerant, non-linear analytic network for modeling and fault detection (open access)

A universal, fault-tolerant, non-linear analytic network for modeling and fault detection

The similarities and differences of a universal network to normal neural networks are outlined. The description and application of a universal network is discussed by showing how a simple linear system is modeled by normal techniques and by universal network techniques. A full implementation of the universal network as universal process modeling software on a dedicated computer system at EBR-II is described and example results are presented. It is concluded that the universal network provides different feature recognition capabilities than a neural network and that the universal network can provide extremely fast, accurate, and fault-tolerant estimation, validation, and replacement of signals in a real system.
Date: March 6, 1992
Creator: Mott, J. E. (Advanced Modeling Techniques Corp., Idaho Falls, ID (United States)); King, R. W.; Monson, L. R.; Olson, D. L. & Staffon, J. D. (Argonne National Lab., Idaho Falls, ID (United States))
System: The UNT Digital Library
Trends in laser-plasma-instability experiments for laser fusion (open access)

Trends in laser-plasma-instability experiments for laser fusion

Laser-plasma instability experiments for laser fusion have followed three developments. These are advances in the technology and design of experiments, advances in diagnostics, and evolution of the design of high-gain targets. This paper traces the history of these three topics and discusses their present state. Today one is substantially able to produce controlled plasma conditions and to diagnose specific instabilities within such plasmas. Experiments today address issues that will matter for future laser facilities. Such facilities will irradiate targets with {approx}1 MJ of visible or UV light pulses that are tens of nanoseconds in duration, very likely with a high degree of spatial and temporal incoherence. 58 refs., 4 figs.
Date: June 6, 1991
Creator: Drake, R.P. (California Univ., Davis, CA (United States) Lawrence Livermore National Lab., CA (United States))
System: The UNT Digital Library
Beam-storage studies in the Fermilab main ring (open access)

Beam-storage studies in the Fermilab main ring

Bunched beams of 100 and 150 GeV have been stored in the Fermilab Main Ring for periods of up to one hour. The observations of beam current and beam profiles are analyzed for the effects of gas scattering, chromaticity and non-linear magnetic field.
Date: May 6, 1982
Creator: MacLachlan, J.A.
System: The UNT Digital Library
Small power plant reverse trade mission (open access)

Small power plant reverse trade mission

This draft report was prepared as required by Task No. 2 of the US Department of Energy, Grant No. FG07-89ID12850 Reverse Trade Mission to Acquaint International Representatives with US Power Plant and Drilling Technology'' (mission). As described in the grant proposal, this report covers the reactions of attendees toward US technology, its possible use in their countries, and an evaluation of the mission by the staff leaders. Note this is the draft report of one of two missions carried out under the same contract number. Because of the diversity of the mission subjects and the different attendees at each, a separate report for each mission has been prepared. This draft report has been sent to all mission attendees, specific persons in the US Department of Energy and Los Alamos National Lab., the California Energy Commission (CEC), and various other governmental agencies.
Date: September 6, 1989
Creator: unknown
System: The UNT Digital Library
Fueling with neutral beams (open access)

Fueling with neutral beams

Neutral beams, which effectively heat and fuel mirror reactors, provide high-energy particles that readily cross magnetic fields to penetrate, heat, and fuel confined plasmas. The potential reliability, efficiency, and cost of large neutral-beam injectors make them desirable components of an operating mirror reactor. Because neutral beams are a poor source of low-energy particles, some other means of fueling large Tokamaks is needed.
Date: October 6, 1977
Creator: Fink, J.H.
System: The UNT Digital Library
Effects of high beam rates on TPC's (open access)

Effects of high beam rates on TPC's

The TPC's (Time Projection Chamber) used in E-810 at the AGS (Alternating Gradient Synchroton) were exposed to silicon ion fluxes equivalent to more than 10{sup 7} minimum ionizing particles per second to measure the distortion of the electric field caused by positive ions in the drift region. Results of these tests are presented and the consequences for the TPC based experiment at RHIC (Relativistic Heavy Ion Collider) are discussed.
Date: February 6, 1992
Creator: Etkin, A.; Eiseman, S. E.; Foley, K. J.; Hackenburg, R. W.; Longacre, R. S.; Love, W. A. et al.
System: The UNT Digital Library
BWR containment failure analysis during degraded-core accidents (open access)

BWR containment failure analysis during degraded-core accidents

This paper presents a containment failure mode analysis during a spectrum of postulated degraded core accident sequences in a typical 1000-MW(e) boiling water reactor (BWR) with a Mark-I wetwell containment. Overtemperature failure of containment electric penetration assemblies (CEPAs) has been found to be the major failure mode during such accidents.
Date: June 6, 1982
Creator: Yue, D.D.
System: The UNT Digital Library
Erratum: First-Principles Theory of Correlated Transport through Nanojunctions [Phys. Rev. Lett. 94, 116802 (2005)] (open access)

Erratum: First-Principles Theory of Correlated Transport through Nanojunctions [Phys. Rev. Lett. 94, 116802 (2005)]

This article provides the correction of an equation that was misprinted in Physical Review Letters 94, 116802 (2005).
Date: May 6, 2005
Creator: Ferretti, A.; Calzolari, Arrigo; Di Felice, Rosa; Manghi, Franca; Caldas, Marilia J.; Buongiorno Nardelli, Marco et al.
System: The UNT Digital Library
Zebrafish May Help Solve Ringing in Vets' Ears (open access)

Zebrafish May Help Solve Ringing in Vets' Ears

Article discussing research by Dr. Ernest J. Moore, professor of molecular pharmacology and audiology. This article discusses his research on tinnitus in zebrafish.
Date: May 6, 2008
Creator: Paul, Marla & Moore, Ernest J.
System: The UNT Digital Library
Comparisons of hydrodynamic beam models with kinetic treatments (open access)

Comparisons of hydrodynamic beam models with kinetic treatments

Hydrodynamic models have been derived by Mark and Yu and by others to describe energetic self-pinched beams, such as those used in ion-beam fusion. The closure of the Mark-Yu model is obtained with adiabatic assumptions mathematically analogous to those of Chew, Goldberger, and Low for MHD. The other models treated here use an ideal gas closure and a closure by Newcomb based on an expansion in V/sub th//V/sub z/. Features of these hydrodynamic beam models are compared with a kinetic treatment.
Date: October 6, 1983
Creator: Boyd, J. K.; Mark, J. W.; Sharp, W. M. & Yu, S. S.
System: The UNT Digital Library
Physics at the Planck scale (open access)

Physics at the Planck scale

Effective supergravity theories suggested by superstrings can be explored to determine their potential for successfully describing both observed physics at zero temperature and an inflationary cosmology. An important ingredient in this study is the dynamics of gaugino condensation, which has been the subject of recent activity. 33 refs., 2 figs.
Date: December 6, 1990
Creator: Gaillard, M.K. (Lawrence Berkeley Lab., CA (USA) California Univ., Berkeley, CA (USA). Dept. of Physics)
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