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BRUTE

Description: BRUTE is an algorithm to derive the implied boundary of a piecepart from the part's wireframe representation. BRUTE's input is an IGES file. The geometry is extracted and used to derive the edge-vertex (EV) topology. BRUTE then uses a divide-and-conquer method to derive all reasonable face-edge-vertex (FEV) topologies from the EV topology. The final step is to determine the geometry of each face by using the geometry of its edges. Any FEV topology that contains a face that is not a valid surfac… more
Date: May 1, 1982
Creator: Christensen, N.C.
Partner: UNT Libraries Government Documents Department
open access

Preparation of thorium-uranium gel spheres

Description: Ceramic oxide spheres with diameters of 15 to 1500 ..mu..m are being evaluated for fabrication of power reactor fuel rods. (Th,U)O/sub 2/ spheres can be prepared by internal or external chemical gelation of nitrate solutions or oxide sols. Two established external gelation techniques were tested but proved to be unsatisfactory for the intended application. Established internal gelation techniques for UO/sub 2/ spheres were applied with minor modifications to make 75% ThO/sub 2/-25% UO/sub 2/ sp… more
Date: January 1, 1980
Creator: Spence, R.D. & Haas, P.A.
Partner: UNT Libraries Government Documents Department
open access

Surface topography measurements over the 1 meter to 10 micrometer spatial period bandwidth

Description: A recently-developed long-trace surface profiling instrument (LTP) is now in operation in our laboratory measuring surface profiles on grazing incidence aspheres and also conventional optical surface. The LTP characterizes surface height profiles in a non-contact manner over spatial periods ranging from 1 meter (the maximum scan length) to 2 mm (the Nyquist period for 1 mm sampling period) and complements the range of our WYKO NCP-1000 2.5X surface roughness profiler (5 mm to 9.8 {mu}m). Using … more
Date: September 1, 1989
Creator: Takacs, P. Z.; Furenlid, K.; DeBiasse, R. A.; Church, E. L. (Brookhaven National Lab., Upton, NY (USA) & Army Research and Development Command, Dover, NJ (USA))
Partner: UNT Libraries Government Documents Department
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Review of some past and present powder metallurgy programs at the Los Alamos Scientific Laboratory

Description: Powder metallurgy programs at LASL are reviewed. Topics covered include: KlWl reactor fuel elements; Phoebus reactor fuel elements, criticality control and poison plate material, structural composites for fuel element supports, and heat shields for fuel element supports; thermionic emitter reactor uranium carbide--zirconium carbide fuel pins, and molybdenum--uranium oxide fuel pins; laser and electron beam fusion targets; and current work in MHD components. (GHT)
Date: January 1, 1977
Creator: Sheinberg, H.
Partner: UNT Libraries Government Documents Department
open access

Application of MOOT to scattering of elastic waves from compound inclusions

Description: It is shown how MOOT (method of optimal truncation, a convergent T-matrix scheme) can be used to calculate elastic wave scattering from compound inclusions, i.e., inclusions which themselves contain flaws - inclusions, voids, or cracks. The general equations are derived, and they are solved for a particular axially-symmetric case - a cracked spherical inclusion immersed in fluid. The crack edge is a circle on the equatorial plane; the crack can extend either inward to the center or outward to t… more
Date: January 1, 1980
Creator: Visscher, W.M.
Partner: UNT Libraries Government Documents Department
open access

Image processing applications in NDE

Description: Nondestructive examination (NDE) can be defined as a technique or collection of techniques that permits one to determine some property of a material or object without damaging the object. There are a large number of such techniques and most of them use visual imaging in one form or another. They vary from holographic interferometry where displacements under stress are measured to the visual inspection of an objects surface to detect cracks after penetrant has been applied. The use of image proc… more
Date: January 1, 1980
Creator: Morris, R.A.
Partner: UNT Libraries Government Documents Department
open access

Weld evaluation on spherical pressure vessels using holographic interferometry

Description: Waist welds on spherical experimental pressure vessels have been evaluated under pressure using holographic interferometry. A coincident viewing and illumination optical configuration coupled with a parabolic mirror was used so that the entire weld region could be examined with a single hologram. Positioning the pressure vessel at the focal point of the parabolic mirror provides a relatively undistorted 360 degree view of the waist weld. Double exposure and real time holography were used to obt… more
Date: May 14, 1980
Creator: Boyd, D.M. & Wilcox, W.W.
Partner: UNT Libraries Government Documents Department
open access

Computer modeling of gas flow and gas loading of rock in a bench blasting environment

Description: Numerical modeling can contribute greatly to an understanding of the physics involved in the blasting process. This paper will describe the latest enhancements to the blast modeling code DMC (Distinct Motion Code) (Taylor and Preece, 1989) and will demonstrate the ability of DMC to model gas flow and rock motion in a bench blasting environment. DMC has been used previously to model rock motion associated with blasting in a cratering environment (Preece and Taylor, 1990) and in confined volume b… more
Date: January 1, 1991
Creator: Preece, D.S.; Baer, M.R. (Sandia National Labs., Albuquerque, NM (United States)) & Knudsen, S.D. (RE/SPEC, Inc., Albuquerque, NM (United States))
Partner: UNT Libraries Government Documents Department
open access

Characterization of spherical surfaces

Description: The surface geometry of a spherical object is often incompletely evaluated because of limitations inherent in the techniques used to measure it. If several techniques measuring different aspects of the surface are combined, a more complete description can be optained.
Date: January 1, 1982
Creator: Gauler, A. L.
Partner: UNT Libraries Government Documents Department
open access

Analysis of laser ultrasonic measurements of surface waves on elastic spheres

Description: In conventional ultrasonic nondestructive evaluation studies, piezoelectric transducers are used to generate sound waves in solids via a couplant that transmits the mechanical motions. In recent years, a different method of generating sound in solids, pulsed laser heating, was introduced by White. This method is noncontacting, requires no coupling medium, and operates directly on the surface of the specimen. Noncontacting ultrasonic detection using laser interferometers of several types has als… more
Date: January 1, 1991
Creator: Koo, L.S. & Telschow, K.L.
Partner: UNT Libraries Government Documents Department
open access

Morphology of rubber modified epoxy encapsulants

Description: Examination of rubber modified epoxy, cured with diethanol amine, via the transmission electron microscope has shown that a broad distribution of rubber particle sizes exists. The average particle size for particles greater than .1 ..mu..m was found to be .8 ..mu..m. A significant population of particles was found whose diameters are less than .1 ..mu..m. Examination of the particle interface showed that the interface between the dispersed phase and the epoxy matrix was sharp within the accurac… more
Date: January 1, 1979
Creator: Sayre, J.A.
Partner: UNT Libraries Government Documents Department
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Angular momentum and the collective modes excited in deep-inelastic processes and in fission. [288 MeV]

Description: The angular momentum effects in deep inelastic processes and fission were studied in the limit of statistical equilibrium. The model consists of two touching liquid drop spheres. Angular momentum fractionation was found to occur along the mass asymmetry coordinate. Thermal excitation of fragment spin is predicted to occur in the degrees of freedom which can bear angular momentum, like wriggling, tilting, bending, and twisting. 17 references.
Date: May 1, 1979
Creator: Moretto, Luciano G.
Partner: UNT Libraries Government Documents Department
open access

What Has Happened to the Survivors of the Early Los Alamos Nuclear Accidents?

Description: Abstract: Two nuclear accidents involving a plutonium sphere just subcritical in size occurred at the Los Alamos Laboratory, LA-1 in 1945 and LA-2 in 1946. Because remote control devices were deemed unreliable at the time, the tamper material (tungsten carbide bricks in LA-1 and beryllium hemispheres in LA-2) was added by hand with the operator standing next to the assembly. In each case the critical size of the assembly was accidentally exceeded and the resultant exponentially increasing chain… more
Date: 1979
Creator: Hempelman, Louis Henry; Lushbaugh, Clarence C. & Voelz, George L.
Partner: UNT Libraries Government Documents Department
open access

Solution to workshop problem 6 (hollow sphere) in the shell approximation with EDDYNET-2D

Description: The problem of the hollow sphere in a sinusoidal field has been solved in the single shell approximation with the code EDDYNET. Solutions with three different meshes are compared among themselves and with axisymmetric solutions obtained by 2-D codes. Agreement is good for total current and for field at points outside the sphere. Agreement is fair for field at interior points, where the field results from near cancellation of applied and induced fields. Agreement is poor for power dissipation an… more
Date: November 1, 1986
Creator: Turner, L. R.
Partner: UNT Libraries Government Documents Department
open access

Selected advances in materials research

Description: Several findings emanating from materials research that should have a beneficial impact on technological advancement in the future are described. The report deals with the GRAPHNOL, a new class of high-temperature brazing alloy for joining refractory components, gel-sphere-pac process for manufacture of nuclear fuel, and noble-metal fuel cladding for service in radioisotope thermoelectric generators designed to provide auxiliary power aboard spacecraft for planetary exploration.
Date: January 1, 1979
Creator: Cunningham, J. E.
Partner: UNT Libraries Government Documents Department
open access

Accelerated thermal aging of rubber modified epoxy encapsulants

Description: A program is outlined to enable prediction of physical properties of rubber modified epoxy encapsulants over the life time of the extended life neutron generators. Preliminary results show that the chief aging phenomenon occurring is increased crosslink density of the epoxy matrix. No changes in the rubber phase have been detected. The effect of increased epoxy crosslink density has been higher volume resistivity at 66/sup 0/C, increased tensile strength, and decreased ultimate elongation.
Date: January 1, 1979
Creator: Sayre, J. A.
Partner: UNT Libraries Government Documents Department
open access

Search for a new force

Description: Horizontal motions of a well-balanced hollow copper sphere floating and almost totally submerged in a well insulated and shielded tank filled with water at 4/sup 0/C were measured in the vicinity of a large cliff. A motion was observed in a direction nearly perpendicular to, and directed away from, the face of the cliff. Conventional explanations for this effect have not been found. The observation is consistent with the existence of a weak, non-Newtonian, substance dependent, medium range forc… more
Date: January 1, 1987
Creator: Thieberger, P.
Partner: UNT Libraries Government Documents Department
open access

Measuring sphericity on a roundness gage

Description: The three-dimensional geometry of a spherical object may be determined by evaluation of a number of two-dimensional roundness measurements which have a known orientation with respect to one another. A suitable set of orientations appears to be one in which the plane of each roundness measurement coincides with every other such plane along a single diameter of the sphere. A device for producing the required set of orientations, adaptable to spheres of varying diameters and designed to avoid dama… more
Date: January 1, 1980
Creator: Gauler, A. L.
Partner: UNT Libraries Government Documents Department
open access

Progress on sol-gel sphere-pac development

Description: The ORNL sol-gel program is reviewed briefly. Advantages of the sol-gel sphere-pac are listed. Three sizes of microspheres are being used; the two largest sized fractions are blended and then loaded into the fuel rod, followed by packing of the smallest microspheres into void spaces using a low-energy vibrator. Sol-gel sphere-pac also appears attractive for breeder reactor fuel fabrication. (DLC)
Date: January 1, 1978
Creator: Suchomel, R R
Partner: UNT Libraries Government Documents Department
open access

The thermal conductivity of beds of spheres

Description: The thermal conductivities (k) of beds of solid and hollow microspheres were measured using two radial heat flow techniques. One technique provided k-data at 300 K for beds with the void spaces between particles filled with argon, nitrogen, or helium from 5 kPa to 30 MPa. The other technique provided k-data with air at atmospheric pressure from 300 to 1000 K. The 300 K technique was used to study bed systems with high k-values that can be varied by changing the gas type and gas pressure. Such s… more
Date: January 1, 1987
Creator: McElroy, D. L.; Weaver, F. J.; Shapiro, M.; Longest, A. W. & Yarbrough, D. W.
Partner: UNT Libraries Government Documents Department
open access

Debris collection from implosion of microballoons

Description: Recovery of krypton from implosion of glass microballoons has been studied in the development of a radiochemical diagnostic for determination of <rho r> /sub fuel/. Collection onto metal surfaces following implosions performed on the OMEGA laser with 1-3 TW (1-2 kJ) of 0.35 ..mu..m light is consistent with an ion implantation mechanism. The dependence of the intrinsic collection efficiency on the energy fluence to the collector surface and its variation in implosions carried out under the same … more
Date: March 28, 1986
Creator: Prussin, S.G.; Lane, S.M.; Richardson, M.C. & Noyes, S.G.
Partner: UNT Libraries Government Documents Department
open access

Hydrogen transport and storage in engineered glass microspheres

Description: New, high-strength, hollow, glass microspheres filled with pressurized hydrogen exhibit storage densities which make them attractive for bulk hydrogen storage and transport. The hoop stress at failure of our engineered glass microspheres is about 150,000 psi, permitting a three-fold increase in pressure limit and storage capacity above commercial microspheres, which fail at wall stresses of 50,000 psi. For this project, microsphere material and structure will be optimized for storage capacity a… more
Date: April 20, 1994
Creator: Rambach, G. D.
Partner: UNT Libraries Government Documents Department
open access

Advanced in Macrostatistical Hydrodynamics

Description: An overview is presented of research that focuses on slow flows of suspensions in which colloidal and inertial effects are negligibly small (Macrostatistical Hydrodynamics). First, we describe nuclear magnetic resonance imaging experiments to quantitatively measure particle migration occurring in concentrated suspensions undergoing a flow with a nonuniform shear rate. These experiments address the issue of how the flow field affects the microstructure of suspensions. In order to understand the … more
Date: August 1, 1993
Creator: Graham, A. L.; Tetlow, N.; Abbott, J. R.; Mondy, L. S. & Brenner, H.
Partner: UNT Libraries Government Documents Department
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