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Fiber optics and microprocessors: a control-system solution for the laser-fusion environment

Description: The use of fiber optics and microprocessors in a distributed computer control system for a 100-kJ CO/sub 2/ laser fusion facility is described. Gas-laser control systems must operate in an environment in which megavolt Marx circuits generate megampere discharges in the laser amplifiers, with attendant high electromagnetic fields. By linking the distributed controls with fiber optics the adverse effect of these fields on the hard-wired controls is mimimized, and the additional advantage of groun… more
Date: January 1, 1978
Creator: Thuot, M.E.
Partner: UNT Libraries Government Documents Department
open access

Creep of whisker-reinforced ceramics

Description: The results of high-temperature creep of various ceramic composites will be reviewed. In particular, creep results for Al{sub 2}O{sub 3} and Si{sub 3}N{sub 4} matrices reinforced with SiC whiskers will be emphasized. For a given temperature, stress and grain size, the creep rate of the Al{sub 2}O{sub 3} composite is usually lower than that of the ceramic matrix. In general, creep at low stresses occurs by grain boundary sliding accommodated by diffusion, whereas higher stresses lead to damage a… more
Date: January 1, 1991
Creator: Routbort, J.L; Goretta, K.C. (Argonne National Lab., IL (United States)); Dominguez-Rodriguez, A. & de Arellano-Lopez, A.R. (Seville Univ. (Spain))
Partner: UNT Libraries Government Documents Department
open access

Optimization of a VISAR for measuring flyer-plate velocities

Description: 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… more
Date: May 6, 1992
Creator: Sweatt, W. C.; Crump, O. B., Jr. & Brigham, W. P.
Partner: UNT Libraries Government Documents Department
open access

Phased-array antenna control by a monolithic photonic integrated circuit, COMPASS

Description: Phased-array antenna systems are well known for rapid beam steering and their ability to bring high power to the target. Such systems are also quite complex and heavy, which have limited their usefulness. The issues of weight, size, power use, and complexity have been addressed through a system named COMPASS (Coherent Optical Monolithic Phased Array Steering System). All phased-array antenna systems need: (1) small size; (2) low power use; (3) high-speed beam steering; and (4) digitally-control… more
Date: January 1, 1991
Creator: Kravitz, S. H.; Hietala, V. M.; Vawter, G. A. & Meyer, W. J.
Partner: UNT Libraries Government Documents Department
open access

Fossil Energy Advanced Research and Technology Development (AR TD) Materials Program semiannual progress report for the period ending September 30, 1991

Description: The objective of the Fossil Energy Advanced Research and Technology Development Materials Program is to conduct research and development on materials for fossil energy applications with a focus on the longer-term and generic needs of the various fossil fuel technologies. The Program includes research aimed toward a better understanding of materials behavior in fossil energy environments and the development of new materials capable of substantial enhancement of plant operations and reliability. … more
Date: April 1, 1992
Creator: Judkins, R.R. & Cole, N.C. (comps.)
Partner: UNT Libraries Government Documents Department
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Thermal strains in titanium aluminide and nickel aluminide composites

Description: Neutron diffraction was used to measure residual thermal strains developed during postfabrication cooling in titanium aluminide and nickel aluminide intermetallic matrix composites. Silicon carbide /Ti 14Al-21Nb, tungsten and sapphire/NiAl, and sapphire and SiC-coated sapphire/NiAl{sub 25}Fe{sub 10} composites were investigated. The thermal expansion coefficient of the matrix is usually greater than that of the fibers. As such, during cooldown, compressive residual strains are generated in the … more
Date: January 1, 1992
Creator: Saigal, A. (Tufts Univ., Medford, MA (United States). Dept. of Mechanical Engineering) & Kupperman, D.S. (Argonne National Lab., IL (United States))
Partner: UNT Libraries Government Documents Department
open access

High temperature fuel cell research and development. Final technical status report, 1 March 1979-31 March 1980. [Molten carbonate fuel cells]

Description: The objective of the program has been to evaluate potential materials for their chemical and physical stability in molten carbonate fuel cell electrolyte. Eleven powdered candidate materials were selected based on previous physical and chemical stability tests at elevated temperatures on solid materials and/or their thermodynamic stability with respect to proposed degradation reactions. The eleven candidate materials, plus gamma lithium aluminate, were characterized prior to corrosion testing u… more
Date: May 1, 1980
Creator: Lessing, P.A.
Partner: UNT Libraries Government Documents Department
open access

Effect of water-bearing fiber in Kevlar 49-epoxy composites

Description: Water has been observed to be adsorbed, and possibly absorbed, by desiccated Kevlar 49 fiber to 6 percent of the fiber weight in 100 percent relative humidity. The effect of the water on the transverse flexural strength and elastic modulus of an aliphatic amine-cured epoxy, unidirectionally reinforced with saturated Kevlar 49, has been determined. Such composites are weaker than those made with fiber equilibrated to 0 percent relative humidity, and the effect persists after a 75/sup 0/C, 16-h p… more
Date: January 1, 1978
Creator: Moss, M.
Partner: UNT Libraries Government Documents Department
open access

Development and utilization of new diagnostics for dense-phase pneumatic transport

Description: Dense-phase pneumatic transport is an attractive means of conveying solids. Unfortunately, because of the high solid concentrations, this transport method is a difficult regime in which to carry out detailed measurements. Hence most details of the flow are unknown. In this context, the main objective of this work is to develop probes for local measurements of solid velocity and holdup in dense gas-solid flows. Because we anticipate the recent theories of rapid granular flows will bring insight … more
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department
open access

Composite-rim flywheel design

Description: The design of a flywheel which incorporates a circumferentially wound rim is described. The design required the selection of materials and configuration for rim and hub, and a means of attaching the rim to the hub. The method used to fabricate prototype flywheels of this design is discussed.
Date: January 1, 1977
Creator: Reedy, E.D. Jr.
Partner: UNT Libraries Government Documents Department
open access

E-Division semiannual report. Progress report, December 1, 1976--May 30, 1977. [LASL]

Description: Detector research and development are described first. Then, briefer reports are given on research on the following topics: electronic temperature monitoring and identification for livestock, electromagnetic probing (for fracture mapping), fiber optics for downhole instrumentation (for weapons testing), adaptive control applied to HVAC systems, energy environmental simulator, and high-temperature electronics. Engineering support (development projects, program support, instrumentation support) a… more
Date: November 1, 1977
Creator: Kelley, P.A. (comp.)
Partner: UNT Libraries Government Documents Department
open access

Improvement of the mechanical reliability of monolithic refractory linings for coal gasification process vessels. Final report

Description: Eighteen heat-up tests were run on nine standard and experimental dual component monolithic refractory concrete linings. These tests were run with a five foot diameter by 14-ft high Pressure Vessel/Test Furnace designed to accommodate a 12-inch thick by 5-ft high refractory lining, heat the hot face to 2000/sup 0/F and expose the lining to air or steam pressures up to 150 psig. Results obtained from standard type linings in the test facility indicated that lining degradation duplicated that obs… more
Date: September 1, 1981
Creator: Potter, R.A. (comp.)
Partner: UNT Libraries Government Documents Department
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Recent Developments in Microshell-Tipped Optical Fibers as High-Pressure Shock Detectors

Description: We describe ongoing development and characterization of Microshell-tipped optical fibers used as impact sensors. We observed a risetime of 15 ns when the probe is used to measure a detonation wave in PETN. We report successful development of two nondestructive tests, radiography and fluorescence, to check the integrity of the sensor. The sensor is now commercially available. 5 refs., 3 figs.
Date: January 1, 1985
Creator: Mayer, F. J.; Maynard, R. L.; Musinski, D. L.; Schmerberg, N. W.; Wixom, M. R. & Benjamin, R. F.
Partner: UNT Libraries Government Documents Department
open access

Probabilistic models of the stress-rupture of composite materials: Phase III. Progress report, June 15, 1978-June 14, 1980

Description: The development of static and time dependent models for the failure of composite materials has been pursued. These models are based on the chain-of-bundles probability model for composite failure wherein local load sharing among non-failed fiber elements in a bundle plays a key role. At the outset, it was believed that the static model was well developed in the literature by others, and that work on the time dependent versions could proceed. In these versions, the viscoelasticity of the matrix … more
Date: March 1, 1980
Creator: Phoenix, S.L.
Partner: UNT Libraries Government Documents Department
open access

VISAR: interferometer quadrature signal recording by electronic streak camera

Description: This short paper describes a demonstration to record the four quadrature signals from a push-pull VISAR velocity interferometer using an electronic streak camera. Optical fibers were used to transmit the interferometer outputs to the camera photocathode. Brightness variations of these signals were recorded on film during the experiment. Velocity information was later recovered from this record to give a continuous velocity history. Anticipated advantages over previous methods are increased time… more
Date: January 1, 1985
Creator: Hemsing, W.F.
Partner: UNT Libraries Government Documents Department
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Irradiation of Metal-Fiber-Reinforced Thoria-Urania. Final Report- Metallurgy Program 6.2.4

Description: Randomly oriented fibers of either molybdenum or niobium were incorporated into hot-pressed pellets of 10, 30, and 50 wt% UO/sub 2/ in ThO/sub 2/ to improve thermal conductivity and thermal shock resistance. Pellets, 9.5 mm in diameter and 9.5 mm in length, were irradiated in NaK capsules, both bare and jacketed with Zircaloy-2, with the annulus between pellet and jacket filled with lead or helium. They were irradiated to burnups ranging up to 34 500 Mwd/T (1 0 x 10/sup 21/ fiss/cc) at central … more
Date: December 1, 1961
Creator: Neimark, L. A.; Kittel, J. H. & Hoenig, C. L.
Partner: UNT Libraries Government Documents Department
open access

Fiber-optic time domain reflectometer

Description: An optical time domain reflectometer is described which combines in one instrument the basic capability to analyze several important fiber characteristics. The device uses the polarization properties of light to enable high sensitivity fault detection close to the fiber input end; its probe pulse temporal characteristics and high gain photodetector in combination provide excellent discontinuity location resolution in long lossy fibers, and give an indication of fiber dispersion at large bandwid… more
Date: January 1, 1978
Creator: Lyons, P. B.; Golob, J. E.; Looney, L. D.; Nelson, M. A. & Davies, T. J.
Partner: UNT Libraries Government Documents Department
open access

Development and utilization of new diagnostics for dense-phase pneumatic transport

Description: In 1988, we proposed a program to develop new diagnostics for dense gas-solid suspensions, with particular interest toward the dense pneumatic transport of cohesive solid plugs. This program included three main objectives, as follows: to develop probes for local measurements of (1) local particle volume fraction and (2) individual particle velocities in dense gas-solid flows; and (3) to construct a bench-scale setup for transporting dense cohesive solid plugs and to analyze data from the result… more
Date: March 2, 1992
Creator: Louge, M. & Jenkins, J.T.
Partner: UNT Libraries Government Documents Department
open access

Time-dependent properties of fiber composites for energy-storage flywheels

Description: Time-dependent deformation and time-dependent strength are being characterized for several candidate polymeric composites for flywheels. This presentation highlights the motivation and the philosophy of the characterization adopted by the authors in establishing the ongoing programs at LLL. This overview is intended to provide a basis for inferring the type of enginering data being generated for different aspects of flywheel design. The details of these data can be obtained from the published r… more
Date: October 25, 1977
Creator: Wu, E.M. & Penn, L.S.
Partner: UNT Libraries Government Documents Department
open access

/sup 1/H, /sup 19/F and /sup 11/B nuclear magnetic resonance characterization of BF/sub 3/:amine catalysts used in the cure of C fiber-epoxy prepregs

Description: The chemical composition of commercial BF/sub 3/:amine complexes are variable and contain BF/sub 4//sup -/ and BF/sub 3/(OH)/sup -/ salts together with other unidentified highly reactive species. The BF/sub 3/:amine complexes, which are susceptible to hydrolysis, also partially convert to the BF/sub 4//sup -/ salt (i.e. BF/sub 4//sup -/NH/sub 3//sup +/C/sub 2/H/sub 5/) upon heating. This salt formation is accelerated in dimethyl sulfoxide solution and in the presence of the epoxides that are pr… more
Date: December 1, 1983
Creator: Happe, J.A.; Morgan, R.J. & Walkup, C.M.
Partner: UNT Libraries Government Documents Department
open access

Industrial recovered-materials-utilization targets for the textile-mill-products industry

Description: The Congress, in the National Energy Conservation and Policy Act of 1978 (NECPA), directed the Department of Energy to establish materials recovery targets for the metals and metal products, paper and allied products, rubber, and textile-mill-products industries. The targets were developed to provide incentives for using energy-saving recorded materials and to provied a yardstick for measuring progress and improvement in this endeavor. The NECPA indicates that the targets should represent the m… more
Date: January 1, 1979
Partner: UNT Libraries Government Documents Department
open access

Termination of plastic-clad fiber. [Plastic-clad silica]

Description: Optical waveguides are ideal in a nuclear weapon environment because of their resistance to electromagnetic interference. Of the fibers on today's market, plastic-clad silica (PCS) is the most radiation resistant and therfore the best choice. Because terminating PCS is complex, this paper attemps to address the major problems associated with these terminations including selecting the proper connector and optimizing the terminating procedures. The sources of losses in the connectors are summariz… more
Date: March 1, 1982
Creator: Nance, W.R.
Partner: UNT Libraries Government Documents Department
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