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Systematic approach to remote maintenance in the fuels and materials examination facility (open access)

Systematic approach to remote maintenance in the fuels and materials examination facility

The Fuels and Materials Examination Facility (FMEF) is systematically analyzed from a remote maintenance standpoint using functional analysis methods. From the analysis the remote maintainability of equipment is ascertained, required tooling lists are formed, and maintenance downtimes are established. These techniques identify deficiencies or inefficiencies in the early design stage where changes have a minimum impact on cost. Special tooling and fixture requirements are minimized by standardizing remote maintenance design features.
Date: November 11, 1979
Creator: Frandsen, G. B.; Nash, C. R.; Divona, C. J. & May, R. F.
System: The UNT Digital Library
Design of a fiber optic multi-tapped computer bus for a pulsed power control system application (open access)

Design of a fiber optic multi-tapped computer bus for a pulsed power control system application

Control system techniques developed and proven on the Shiva laser have been extended to incorporate new electronic and electo-optic devices as well as conform to unique operational requirements of the 300 terawatt Nova laser system. This paper describes one segment of the control system being designed for the Nova laser currently under design/construction at Lawrence Livermore Laboratory. The specific segment covered is the control system bus structure responsible for power conditioning and real-time control functions.
Date: October 11, 1979
Creator: Gritton, D.G.; Berkbigler, L.W. & Oicles, J.A.
System: The UNT Digital Library
Diagnostic measurements related to laser driven inertial confinement fusion (open access)

Diagnostic measurements related to laser driven inertial confinement fusion

Scientists at the Lawrence Livermore Laboratory have been conducting laser driven inertial confinement fusion experiments for over five years. The first proof of the thermonuclear burn came at the Janus target irradiation facility in the spring of 1975. Since that time three succeedingly higher energy facilities have been constructed at Livermore, Cyclops, Argus and Shiva, where increased fusion efficiency has been demonstrated. A new facility, called Nova, is now in the construction phase and we are hopeful that scientific break even (energy released compared to incident laser energy on target) will be demonstrated here in early 1980's. Projected progress of the Livermore program is shown.
Date: September 11, 1979
Creator: Campbell, D.E.
System: The UNT Digital Library
Preferential acceleration in collisionless supernova shocks (open access)

Preferential acceleration in collisionless supernova shocks

The preferential acceleration and resulting cosmic ray abundance enhancements of heavy elements (relative to protons) are calculated in the collisionless supernova shock acceleration model described by Eichler in earlier work. Rapidly increasing enhancements up to several tens times solar ratios are obtained as a function of atomic weight over charge at the time of acceleration. For material typical of hot phase interstellar medium, good agreement is obtained with the observed abundance enhancements.
Date: September 11, 1979
Creator: Hainebach, K.; Eichler, D. & Schramm, D.
System: The UNT Digital Library
Progress in mirror machine research (open access)

Progress in mirror machine research

The Mirror Fusion Program in the US is now focused on two concepts that can obtain high values of the power gain factor Q. These are the tandem mirror and field reversed mirror concepts. A new facility called TMX has been constructed to test the principles of the tandem mirror. A further attempt to create field reversal is being carried out in the 2XIIB facility (renamed Beta II) with neutral beam injection into a reversed-field target plasma to be created by a magnetized coaxial gun. During the next 5 years, the main mirror facilities in the US will be the TMX, Beta II, and a large mirror device called MFTF scheduled to operate by 1982. The program based on these facilities will be outlined and initial experimental results from TMX will be discussed.
Date: September 11, 1979
Creator: Fowler, T. K. & Coensgen, F. H.
System: The UNT Digital Library
Elastic and plastic properties of uranium dioxide from 5 to 330 GPa (open access)

Elastic and plastic properties of uranium dioxide from 5 to 330 GPa

We have measured the shock-compression parameters for UO/sub 2/ to 330 GPa. The Hugoniot elastic limit was found to be 5.7 GPa. Evidence for a shock-induced phase transition was observed at about 54 GPa.
Date: July 11, 1979
Creator: Gust, W.H.
System: The UNT Digital Library
Surface Analytical Problems in the Laser Fusion Energy Program at Lawrence Livermore Laboratory (open access)

Surface Analytical Problems in the Laser Fusion Energy Program at Lawrence Livermore Laboratory

The Lawrence Livermore Laboratory is involved in a program to produce energy by the laser-induced fusion of microtargets. These laser systems have become very large and powerful. In Shiva, the amplifier rods common to smaller systems have been replaced with an array of large elliptical amplifier discs with major axes as large as 42 cm. Under the high power levels of these devices it is imperative that the optical surfaces remain scrupulously clean. All units are therefore cleaned, assembled, and operated under clean room conditions. In spite of such precautions, persistent problems arise. These can be grouped into three categories: (1) the appearance of unknown contaminants from unknown sources, (2) the transfer of material from one part of the assembly to another, and (3) laser beam damage to the optical surfaces. Theses problems and their resolution by surface analytical methods are discussed. In addition some unique problems associated with the very large sample sizes are described.
Date: July 11, 1979
Creator: Meisenheimer, R.G. & Fischer, J.W.
System: The UNT Digital Library
Tools for assessing and designing material control processing monitors (open access)

Tools for assessing and designing material control processing monitors

This paper reviews some of the computational tools for the assessment and design of Material Control and Accounting (MC and A) process monitoring components and illustrates their application to a Pu evaporator/concentrator unit operation. The codes include: (1) a general-purpose dynamic simulator for modeling the physical phenomenology of various chemical unit operations and their associated measurement systems, (2) an estimation code for simulating the operation of some modern signal processing algorithms (Kalman filter formulation), and (3) a set of detection algorithms for simulating on-line material loss detection algorithms for simulating on-line material loss detection. These codes can be used to address the issues of on-line material accounting and diversion detection for safeguarding SNM, and specifically with respect to arriving at meaningful performance measures. They can be used to compare state-of-the-art with state-of-the-practice and to study cost benefit tradeoffs. They are capable of treating stochastic models with nonlinear process and measurement dynamics and as a result should provide means for better designs of MC and A process monitoring components.
Date: July 11, 1979
Creator: Dunn, D.R.; Candy, J.V. & Rozsa, R.B.
System: The UNT Digital Library
Sintering kinetics of pure and doped boron carbide (open access)

Sintering kinetics of pure and doped boron carbide

The sintering of pure and doped boron carbide was investigated over the temperature range 1898 to 2380/sup 0/K and at additive levels ranging from 0.75 to 10.0%. The addition of 0.75 and 3.8 wt% of AlF/sub 3/, Ni, Fe, and Cu deactivated the sintering of B/sub 4/C at all temperatures. In contrast, the addition of 10.0 wt% these additives resulted in enhanced shrinkage in B/sub 4/C for the temperatures 1898 and 2133/sup 0/K. At the highest temperature, 2380/sup 0/K, the addition of 10.0 wt% AlF/sub 3/ was the only case where enhanced shrinkage was observed. In this case, x-ray analysis showed the formation of a B/sub 12/C/sub 2/Al compound and the release of fluorine. These results are interpreted in terms of a grain-boundary diffusion process for pure and doped B/sub 4/C.
Date: June 11, 1979
Creator: Lange, R. G.; Munir, Z. A. & Holt, J. B.
System: The UNT Digital Library
Thermal-stress analysis of rock formations for nuclear fuel and waste storage (open access)

Thermal-stress analysis of rock formations for nuclear fuel and waste storage

ADINA and ADINAT in partnership have provided a unique tool for analysis of heat flow, temperature distribution, and underground stresses and deformations due to excavation and storage of nuclear fuel and/or waste cannisters in hard rock formations. During this work we have determined successful and unsuccessful combinations of elements and properties for both the thermal and the stress analyses. In addition, we have determined a need for thermal radiation transport between portions of the model, as contrasted to radiation between the model and its surroundings. This latter need has been met in the interim by use of nonlinear bar conductors, and it will be satisfied in the future by a special user subroutine at ADINAT. The geological modeling was preceeded by a period of code testing and verification during which it was found that at least one material model did not produce correct thermal stresses even though the thermal deformations were correct. We also found that thermal stresses were likely to be in apparent error due to differences in the way in which ADINA interpolates the temperature and strain fields within each element. Solutions to this problem are discussed.
Date: June 11, 1979
Creator: Greenlaw, R.C. & Gerhard, M.A.
System: The UNT Digital Library
ATOMLLL: atoms with shading and highlights (open access)

ATOMLLL: atoms with shading and highlights

The ATOMS program, written at Bell Telephone Laboratory, is capable of determining the visible portions of a scene consisting of interpenetrating spheres and cylinders, put together to represent space-filling or ball-and-stick molecular models. The Lawrence Livermore Laboratory version contains enhancements to add shading and highlights, and to render the spheres on film as ellipses, so they will appear round when projected in various wide-screen formats. The visible parts of each sphere or cylinder are shaded by a minicomputer controlling the film recorder, thus releasing the main computer from transferring the millions of intensity values for each frame. The minicomputer is microprogrammed with an efficient algorithm for the intensities, which uses the color look-up tables in the film recorder to store the reflectance as a function of angle of incidence. 8 references.
Date: May 11, 1979
Creator: Max, N.L.
System: The UNT Digital Library
Fabrication of glass sphere laser fusion targets (open access)

Fabrication of glass sphere laser fusion targets

We have developed processes at LLL for mass producing the high quality glass microspheres required for current laser fusion targets. Here we describe the methods and the materials used in our liquid-droplet and dried-gel systems. Glass microspheres ranging from 70 to 600 microns O.D., with walls from 0.5 to 18 microns thick and which satisfy the exacting surface and symmetry specifications of targets for high density experiments are now produced routinely.
Date: May 11, 1979
Creator: Hendricks, C. D.; Rosencwaig, A.; Woerner, R. L.; Koo, J. C.; Dressler, J. L.; Sherohman, J. W. et al.
System: The UNT Digital Library
Characteristics of thick non-planar SiO/sub 2/ coatings (open access)

Characteristics of thick non-planar SiO/sub 2/ coatings

We have successfully developed a new process for making strong, smooth, thick SiO/sub 2/ films on hemispherical Kovar mandrels of various sizes designed for multishell Laser Fusion Targets. The surface finish obtainable with a 13 ..mu..m thick SiO/sub 3/ coating on a 260 ..mu..m dia. mandrel is approximately 30 nm peak-to-peak, with a few defects of roughly 0.3 ..mu..m deep. The rf magnetron sputtered SiO/sub 2/ films were dense and crystalline.
Date: April 11, 1979
Creator: Meyer, S. F. & Hsieh, E. J.
System: The UNT Digital Library
Experimental Evaluation of Phase Change Material Building Walls Using Small Passive Test Boxes (open access)

Experimental Evaluation of Phase Change Material Building Walls Using Small Passive Test Boxes

Macroencapsulated PCM cemented within masonry building blocks can markedly increase the effectiveness of an equivalent volume of concrete for use as a mass wall for passive solar applications. Various hydrocarbons and hydrated salts were tested. The test procedure and results are presented and discussed. Of the PCM's tested, the most promising candidate material is calcium chloride hexahydrate. The best performing PCM blocks performed on a par with a massive masonry design. (WHK)
Date: January 11, 1979
Creator: Collier, R. Kirk & Grimmer, Derrick P.
System: The UNT Digital Library
Signatures of the various regions of the outer magnetosphere in the pitch angle distributions of energetic particles (open access)

Signatures of the various regions of the outer magnetosphere in the pitch angle distributions of energetic particles

An account is given of the obervations of the pitch angle distributions of energetic particles in the near equatorial regions of the Earth's magnetosphere. The emphasis is on relating the observed distributions to the field configuration responsible for the observed effects. The observed effects relate to drift-shell splitting, to the breakdown of adiabatic guiding center motion in regions of sharp field curvature relative to partial gyro radii, to wave-particle interactions, and to moving field configurations. 39 references.
Date: December 11, 1978
Creator: West, H. I., Jr.
System: The UNT Digital Library
The Status of Information for Consumers of Small Wind Energy Systems. (open access)

The Status of Information for Consumers of Small Wind Energy Systems.

None
Date: December 11, 1978
Creator: Weis, P.
System: The UNT Digital Library
Mirror hybrid reactors (open access)

Mirror hybrid reactors

The fusion-fission hybrid is a combination of the fusion and fission processes, having features which are complementary. Fission energy is running out of readily available fuel, and fusion has extra neutrons which can be used to breed that fission fuel. Fusion would have to take on an extra burden of radioactivity, but this early application would give fusion, which does not work well enough now to make power, practical experience which may accelerate development of pure fusion.
Date: September 11, 1978
Creator: Moir, Ralph W.
System: The UNT Digital Library
Statistical analysis of absorptive laser damage in dielectric thin films (open access)

Statistical analysis of absorptive laser damage in dielectric thin films

The Weibull distribution arises as an example of the theory of extreme events. It is commonly used to fit statistical data arising in the failure analysis of electrical components and in DC breakdown of materials. This distribution is employed to analyze time-to-damage and intensity-to-damage statistics obtained when irradiating thin film coated samples of SiO/sub 2/, ZrO/sub 2/, and Al/sub 2/O/sub 3/ with tightly focused laser beams. The data used is furnished by Milam. The fit to the data is excellent; and least squared correlation coefficients greater than 0.9 are often obtained.
Date: September 11, 1978
Creator: Budgor, A. B. & Luria-Budgor, K. F.
System: The UNT Digital Library
Spectral decomposition in advection-diffusion analysis by finite element methods (open access)

Spectral decomposition in advection-diffusion analysis by finite element methods

In a recent study of the convergence properties of finite element methods in nonlinear fluid mechanics, an indirect approach was taken. A two-dimensional example with a known exact solution was chosen as the vehicle for the study, and various mesh refinements were tested in an attempt to extract information on the effect of the local Reynolds number. However, more direct approaches are usually preferred. In this study one such direct approach is followed, based upon the spectral decomposition of the solution operator. Spectral decomposition is widely employed as a solution technique for linear structural dynamics problems and can be applied readily to linear, transient heat transfer analysis; in this case, the extension to nonlinear problems is of interest. It was shown previously that spectral techniques were applicable to stiff systems of rate equations, while recent studies of geometrically and materially nonlinear structural dynamics have demonstrated the increased information content of the numerical results. The use of spectral decomposition in nonlinear problems of heat and mass transfer would be expected to yield equally increased flow of information to the analyst, and this information could include a quantitative comparison of various solution strategies, meshes, and element hierarchies.
Date: August 11, 1978
Creator: Nickell, R.E.; Gartling, D.K. & Strang, G.
System: The UNT Digital Library
The ORNL Residential Use Model (open access)

The ORNL Residential Use Model

None
Date: February 11, 1978
Creator: Hirst, E.
System: The UNT Digital Library
Technique for full surface examination of small spheres in the scanning electron microscope (open access)

Technique for full surface examination of small spheres in the scanning electron microscope

In response to the increasing severity of target surface finish requirements for laser fusion experiments, it has become necessary to examine spherical targets in the Scanning Electron Microscope prior to laser irradiation on an orderly nondestructive basis. A new sample manipulation technique has been developed which rolls a thin wall sphere through 4..pi.. steradians without damage and allows easy recovery by placing the sphere between two parallel plane surfaces formed in silicone rubber on the ends of two 0.9 mm capillaries. Mechanical slides, actuated by normal stage controls, cause the capillaries in contact with the sphere to translate laterally and roll the ball. Using theta Z and theta Y motions, the entire surface of the sphere can be brought into a position for examination. With the capillaries oriented for best secondary electron collection and conductively coated, resolutions comparable with traditional mounting techniques are attained. A side looking tilted crystal Si(Li) detector has been incorporated to increase the utility of the system and allow simultaneous EDX microanalysis.
Date: January 11, 1978
Creator: Ward, C.M.; Hendricks, C.D. & Weinstein, B.W.
System: The UNT Digital Library
New Developments in Ultrasonic Imaging of the Chest and Other Body Organs. [Personnel Monitoring for Pu Deposited in Lungs] (open access)

New Developments in Ultrasonic Imaging of the Chest and Other Body Organs. [Personnel Monitoring for Pu Deposited in Lungs]

The accurate measurement of transuranic elements deposited in the lung is a complex task. One of the problems is measuring uranium-L x-rays associated with plutonium passing through the chest of an accidentally exposed subject. Because the normal human chest-wall thickness varies from about 1 to 4.5 cm, it is important that an accurate determination be made for every person counted for plutonium or for other heavy elements with similar emissions. An ultrasonic B-scanning system (brightness modulated time-base) was developed for defining the structure within the body. Computer programs were written to determine the distance between the lung and chest-wall interface and the outer surface of the chest wall at several points on each scan. These points are exponentially averaged to obtain an average chest-wall thickness that is used, with other information, to derive a calibration factor for plutonium in the subject. It is also combined with the counting data to obtain the plutonium lung burden. Since photon transmission characteristics differ in fat and soft tissue, assessing the fat content is important and can provide a correction factor for counter sensitivity when viewing various organs. The main advantage of the B-scanning and three-dimensional systems are discussed.
Date: November 11, 1977
Creator: Campbell, G. W. & Anderson, A. L.
System: The UNT Digital Library
Energy planning and management in developing countries: thoughts concerning a conceptual framework (open access)

Energy planning and management in developing countries: thoughts concerning a conceptual framework

The unique characteristics of the energy situation in developing countries imposes a unique set of requirements on analytical techniques used for energy planning. The urgency of the situation requires the rapid development and use of simplified models which make maximum use of available data but which can reflect the international energy context. Those techniques must also be able to deal with central energy/development issues such as energy equity or the energy implication of social equity policies, centralized vs. decentralized development, and urbanization.
Date: October 11, 1977
Creator: Nathans, R. & Palmedo, P.F.
System: The UNT Digital Library
Fusion devices (open access)

Fusion devices

Three types of thermonuclear fusion devices currently under development are reviewed for an electric utilities management audience. Overall design features of laser fusion, tokamak, and magnetic mirror type reactors are described and illustrated. Thrusts and trends in current research on these devices that promise to improve performance are briefly reviewed. Twenty photographs and drawings are included. (RME)
Date: October 11, 1977
Creator: Fowler, T.K.
System: The UNT Digital Library