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Computer simulation of LMFBR piping systems. [Accident conditions]

Description: Integrity of piping systems is one of the main concerns of the safety issues of Liquid Metal Fast Breeder Reactors (LMFBR). Hypothetical core disruptive accidents (HCDA) and water-sodium interaction are two examples of sources of high pressure pulses that endanger the integrity of the heat transport piping systems of LMFBRs. Although plastic wall deformation attenuates pressure peaks so that only pressures slightly higher than the pipe yield pressure propagate along the system, the interaction of these pulses with the different components of the system, such as elbows, valves, heat exchangers, etc.; and with one another produce a complex system of pressure pulses that cause more plastic deformation and perhaps damage to components. A generalized piping component and a tee branching model are described. An optional tube bundle and interior rigid wall simulation model makes such a generalized component model suited for modelling of valves, reducers, expansions, and heat exchangers. The generalized component and the tee branching junction models are combined with the pipe-elbow loop model so that a more general piping system can be analyzed both hydrodynamically and structurally under the effect of simultaneous pressure pulses.
Date: January 1, 1977
Creator: A-Moneim, M.T.; Chang, Y.W. & Fistedis, S.H.
Partner: UNT Libraries Government Documents Department

REPASSIVATION STUDIES OF ALUMINUM USING A ROTATING STRIP ELECTRODE

Description: In this work a technique was described to study the repassivation of bare metal surfaces. The advantage of this approach over other techniques is the ease with which multiple repassivation events can be studied. The repassivation rate of aluminum was found to depend on the anion in solution. Repassivation rates are higher for aluminum in phosphate and sulfate solutions compared to borate. It is possible that borate may interact more strongly than sulfate or phosphate on the bare aluminum surface blocking the diffusion of oxygen or changing the rate of repassivation.
Date: September 1, 1977
Creator: ALDYKIEWICZ,A.J.,JR. & ISAACS,H.S.
Partner: UNT Libraries Government Documents Department

BNL Archive and Dissemination System. [For accessing data files constructed at separate places and times]

Description: The Brookhaven National Laboratory Archive and Dissemination System (BNLADS) is designed to deal with the record keeping associated with archiving and disseminating sequential files through a computer network. This data base management system (DBMS) is implemented in a host language that is a subset of PL/I. The stored sequential files that can be dealt with by the BNLADS must be in character mode (ASCII, BCD, EBCDIC). The accessing of fields is specified by a format description which allows for forward processing of fields only. The structure of a case type statement allows for a data field determining a format sequence from a set of format sequences. A data description language (DDL) was devised to describe the accessing sequence of stored sequential files. A data model definition gives the user a view of the content of each stored sequential file. The DDL requires all field type references to contain the field name, so that the BNLADS can access all stored sequential files by logical field name and can write stored sequential files by stating the logical field name without the necessity of referring to formats. The BNLADS is architected in a stratified form in which the application programs are built on the accessing procedures. Below this level, the procedures become dependent upon the compiler implementation of the host language PL/I and the operating system. In this manner, BNLADS can be used on most manufacturer's hardware and exhibits the desired property of data independence. 5 figures.
Date: February 1, 1977
Creator: Abbey, S; Fuchel, K; Heller, J; Lin, K S & Osterer, L
Partner: UNT Libraries Government Documents Department

Important aspects of radiation shielding for fusion reactor tokamaks

Description: Radiation shielding is a key subsystem in tokamak reactors. Design of this shield must evolve from economic and technological trade-off studies that account for the strong interrelations among the various components of the reactor system. These trade-offs are examined for the bulk shield on the inner side of the torus and for the special shields of major penetrations. Results derived are applicable for a large class of tokamak-type reactors.
Date: April 30, 1977
Creator: Abdou, M. A.
Partner: UNT Libraries Government Documents Department

Radiation considerations for superconducting fusion magnets

Description: Radiation environment for the magnets is characterized for various conditions expected for tokamak power reactor operation. The radiation levels are translated into radiation effects using available experimental data. The impact of the tradeoffs in radiation shielding and the change in the properties of the superconducting magnets on reactor performance and economics is examined. It is shown that (1) superconducting magnets in fusion reactors will operate at much higher radiation level than was previously anticipated; (2) additional data on radiation damage is required to better accuracy than is presently available in order to accurately quantify the change in properties in the superconducting magnet components; and (3) there is a substantial penalty for increasing (or overestimating) the shielding requirements. A perspective of future tokamak power reactors is presented and questions relating to desirable magnetic field strength and selection of materials for superconducting magnets are briefly examined.
Date: January 1, 1977
Creator: Abdou, M. A.
Partner: UNT Libraries Government Documents Department

Impact of major design parameters on the economics of Tokamak power plants

Description: A parametric systems studies program is now in an active stage at Argonne National Laboratory. This paper presents a summary of results from this systems analysis effort. The impact of major design parameters on the economics of tokamak power plants is examined. The major parameters considered are: (1) the plant power rating; (2) toroidal-field strength; (3) plasma ..beta../sub t/; (4) aspect ratio; (5) plasma elongation; (6) inner blanket/shield thickness; and (7) neutron wall load. The performance characteristics and economics of tokamak power plants are also compared for two structural materials (stainless steel and a vanadium alloy).
Date: November 1, 1977
Creator: Abdou, M.A.; Ehst, D.; Maroni, V. & Stacey, W.M. Jr.
Partner: UNT Libraries Government Documents Department

Speciation studies of radionuclides in low level wastes and process waters from pressurized water reactor

Description: Physicochemical characterization studies of aqueous process streams at San Onofre Generating Station Unit No. 1 are providing important source term information concerning the forms of radionuclides being released into the marine environment. The primary coolant, secondary steam condensate, processed low level wastes and tertiary coolant were sampled at several different times in the nuclear fuel cycle. Rdionuclides were partitioned into particulate, cationic, anionic, and nonionic species in the reactor process streams, and into particulate and soluble species in the tertiary seawater coolant. Characterization of the particulate species has included a detailed size distribution. The purpose of this research was to provide information concerning chemical and physical forms of the radionuclides being released to the coastal zone from a nuclear generating station in order to facilitate design of radiobiological studies necessary for assessment of their environmental significance.
Date: October 1, 1977
Creator: Abel, K. H.; Robertson, D. E.; Crecelius, E. A. & Silker, W. B.
Partner: UNT Libraries Government Documents Department

Caging in high energy reactions. [Role of the cage effect in hot atom reactions]

Description: The concept of caging high energy reactions is considered. It is noted that there is no easy and unambiguous way, short of a complete and very tedious product and mechanistic analysis, which is feasible only for very few systems, to determine the contribution made by caging. It is emphasized that some products resulting from the hot reaction with a certain substrate may be formed via caging while others are not. In research on the mechanism of caging the results of Roots work on the reactions of hot /sup 18/F with the CF/sub 3/CH/sub 3/ system seem to provide evidence for caging, with /sup 18/F being the caged moiety, thus proceeding via a radical--radical recombination mechanism. Their work with H/sub 2/S additive also seems to indicate that scavenging via hydrogen abstraction from H/sub 2/S to form does not interfere with the radical--radical recombination consistent with Bunkers molecular approach to explain the cage effects. In other research a series of observations resulting from stereochemical and combined stereochemical density variation techniques seem to favor a caged-complex. It is clear that a more conclusive answer can only be reached by more systematic studies, utilizing the whole range of nuclear reactions such as (n,2n), (n,..gamma..) and E.C. processes in mechanistically well defined systems to elucidate the effect of variations in the recoil energies, by carrying out studies in different solvents or host substances to assess the effect of the physical parameters, such as molecule size and intermolecular interactions on the escape probability or caging efficiencies.
Date: January 1, 1977
Creator: Ache, H J
Partner: UNT Libraries Government Documents Department

Comparison of the thermodynamic properties and high temperature chemical behavior of lanthanide and actinide oxides

Description: The thermodynamic properties of the lanthanide and actinide oxides are examined, compared, and associated with a variety of high temperature chemical behavior. Trends are cited resulting from a number of thermodynamic and spectroscopic correlations involving solid phases, species in aqueous solution, and molecules and ions in the vapor phase. Inadequacies in the data and alternative approaches are discussed. The characterization of nonstoichiometric phases stable only at high temperatures is related to a network of heterogeneous and homogeneous equilibria. A broad perspective of similarity and dissimilarity between the lanthanides and actinides emerges and forms the basis of the projected needs for further study.
Date: January 1, 1977
Creator: Ackermann, R. J. & Rauh, E. G.
Partner: UNT Libraries Government Documents Department

Thermal conductivity of S. E. New Mexico rocksalt and anhydrite. [Saltcrete]

Description: The thermal conductivity of several rocksalt materials has been determined. Some of the materials were core samples from well AEC 8, Carlsbad, New Mexico. These samples ranged from nearly pure halite (NaCl) to nearly pure anhydrite (CaSO/sub 4/). Core sample crystallite size ranged from about 3 centimeters to essentially packed salt sand (approx. = 0.5mm). The samples exhibited thermal conductivities from approx. = 1.5 to 7.5 W/mK which depended upon purity and grain size. A one meter cube of rocksalt from the Mississippi Chemical Company's S.E. New Mexico potash mine was obtained for other experiments. The thermal conductivity of one sample from each of the orthogonal directions of the cube was measured. This material had a high conductivity of approx. = 8.5 W/mK and was very isotrophic. A core of rocksalt from the Morton Salt Company, Paynesville, Ohio had a thermal conductivity of 6 W/mK, which is in the upper band of the results on cores from well AEC 8. Finally, a concrete made with salt sand and rocksalt aggregate was determined to have a conductivity of approx. = 2 W/mK. A longitudinal heat flow apparatus was used to determine the thermal conductivity. An analysis of the experiment gave an accuracy within +- 15% on geological samples and within +- 10% on 304 stainless steel. 8 references, 5 figures, 2 tables.
Date: January 1, 1977
Creator: Acton, R.U.
Partner: UNT Libraries Government Documents Department

Dosimeter sample preparation, quality assurance, and materials development for the ILRR, FRMDC, and FFTF dosimetry programs

Description: Since the IRML dosimeter program began in 1971, approximately 1900 vanadium encapsulated dosimeters and approximately 100 aluminum encapsulated metal fission foils have been prepared to meet TLRR, FRMDC, and FFTF requirements. Development efforts have focused on cost reduction in fabrication as well as characterization of both pure and dilute materials to meet the desired accuracy goals of +-0.5 and +-1.0 percent (2 sigma), respectively. One important requirement of the dosimeter program is that the dosimeter materials be encapsulated in high purity vanadium. To meet this requirement over the next ten years, an adequate supply of vanadium must be maintained. Efforts were begun to locate and characterize batches of high purity vanadium to meet this requirement. In addition, efforts were initiated to obtain the necssary vanadium capsules, to be fabricated from ILRR material, on a competitive bid basis from a commercial supplier. Quality assurance procedures were established to maintain homogeneity among the various batches of dosimeters produced. Procedures developed for producing the 1.270-mm diameter capsules were adapted to the loading of the more recently required 0.889-mm diameter capsules. Vanadium capsules are to be used in neutron energy spectra, flux and fluence characterization studies during start-up and run phases of the FFTF.
Date: January 1, 1977
Creator: Adair, H. L.; Kobisk, E. H.; Setaro, J. A.; Quinby, T. C. & Dailey, J. M.
Partner: UNT Libraries Government Documents Department

Preparation and characterization of /sup 241/Am and /sup 3/H targets

Description: This paper describes actinide oxide deposits in support of reactor technology, high purity /sup 241/Am metal fabrication for material property studies and tritium target fabrication in support of materials research conducted at LLL.
Date: January 1, 1977
Creator: Adair, H.L.
Partner: UNT Libraries Government Documents Department

Current trends in methods for neutron diffusion calculations

Description: Current work and trends in the application of neutron diffusion theory to reactor design and analysis are reviewed. Specific topics covered include finite-difference methods, synthesis methods, nodal calculations, finite-elements and perturbation theory.
Date: January 1, 1977
Creator: Adams, C. H.
Partner: UNT Libraries Government Documents Department

Radiation hardened field oxide

Description: This paper describes the development of a radiation-tolerant field oxide compatible with both MOS and bipolar technologies. Data is presented which illustrates that nonguardbanded devices utilizing conventional field oxide structures cannot be expected to survive an ionizing radiation dose above approximately 5 x 10/sup 4/ rads (Si) due to inversion of p-type silicon surfaces under metallized areas. The radiation hardened oxide was evaluated with both aluminum and polycrystalline silicon gate MOS structures and they conclusively demonstrate that this oxide eliminates the field inversion problem for radiation levels in excess of 10/sup 6/ rads (Si).
Date: January 1, 1977
Creator: Adams, J. R.; Dawes, W. R. & Sanders, T. J.
Partner: UNT Libraries Government Documents Department

Considerations in the evaluation of the human element of a safeguards system

Description: By understanding the human system and its function, then a structure for evaluating the human system can be developed. This understanding must be available at the research and development levels, and must occur at the working level so that individuals who impact the system will have a common goal in mind. Then by appropriate coordination and review, a system can be developed which will function as designed with a high degree of assurance.
Date: January 1, 1977
Creator: Adams, K.G. & Trujillo, A.A.
Partner: UNT Libraries Government Documents Department

Energy calibration scheme for acoustic emission

Description: The calibration technique described is an attempt to determine the actual energy release from the events causing emission bursts in beryllium and to quantitatively evaluate the effects of specimen geometry on the apparent energy per burst. (GHT)
Date: September 13, 1977
Creator: Adams, R. O. & Heiple, C. R.
Partner: UNT Libraries Government Documents Department

Material control assessment procedure

Description: The material control system assessment procedure being developed by the Lawrence Livermore Laboratory for the U.S. Nuclear Regulatory Commission is reviewed. It consists of five major sections: Target Identification, Adversary Sequence and Simuli Generation, Material Control System Response Determination, Safeguard System Outcome Determination, and Safequard System Utility Determination. When adopted, this procedure will minimize safeguards licensing problems by providing compatibility with future performance based regulations, explicit evaluation rules and requirements, well-defined trade-off structures, and user-oriented and systematic evaluation and design tools.
Date: June 1, 1977
Creator: Adams, R. W. & Spogen, L. R.
Partner: UNT Libraries Government Documents Department

Material control assessment procedure

Description: The material control system assessment procedure being developed by the Lawrence Livermore Laboratory for the U.S. Nuclear Regulatory Commission is reviewed. It consists of five major sections: Target Identification, Adversary Sequence and Simuli Generation, Material Control System Response Determination, Safeguard System Outcome Determination, and Safeguard System Utility Determination. When adopted, this procedure will reduce safeguards licensing problems by providing compatibility with future performance based regulations, explicit evaluation rules and requirements, well-defined trade-off structures, and user-oriented and systematic evaluation and design tools.
Date: June 1, 1977
Creator: Adams, R. W. & Spogen, L. R.
Partner: UNT Libraries Government Documents Department

DAMAGE TO MITOCHONDRIAL ELECTRON TRANSPORT AND ENERGY COUPLING BY VISIBLE LIGHT

Description: Plutonium is one of the principal materials of both commercial and military nuclear power. It is produced primarily in fission reactors that contain uranium fuel, and its importance arises from the fact that a large portion of the plutonium produced is fissile: like uranium 235, the mass 239 and 241 isotopes of plutonium can be caused to fission by neutrons, including those with low energy. Because such fission events also release neutrons, substantial amounts of energy can be extracted from plutonium in a controlled or an explosive nuclear chain reaction. Now that commercial nuclear reactors provide a noticeable fraction of United States (and world) electrical energy, these reactors account for most plutonium production. For the most part, this material now remains in the irradiated fuel after removal from reactors, but should this fuel be reprocessed, the plutonium could be recycled to provide part and even most of the fissile content of fresh fuel. For the current generation of water-cooled reactors, the amount of plutonium to be recycled is substantial. In fast breeder reactors, designed to produce more fissile material than they destroy, considerably larger quantities of plutonium would be recycled. In other types of advanced reactors, particularly those which depend heavily on thorium as the material from which fissile material (primarily uranium 233) is produced, the amount of plutonium to be handled would be considerably reduced. Because plutonium is a highly toxic substance, great care is taken to contain it at the sites and facilities where it is stored or handled. In addition, it is necessary that devices be available to monitor any releases from these facilities into environmental media and to measure concentrations of plutonium in these media. The radiation protection standards are so strict for plutonium that only small releases and low concentrations can be tolerated. Such considerations, ...
Date: September 1, 1977
Creator: Aggarwal, B.B.; Quintanilha, A.T.; Cammack, R. & Packer, L.
Partner: UNT Libraries Government Documents Department

Characteristics of the ISABELLE vacuum system

Description: A discussion is given of the complete vacuum system of ISABELLE, emphasizing those design characteristics dictated by high vacuum, the avoidance of beam current loss, and the reduction of background. The experimental and theoretical justifications for the design are presented.
Date: January 1, 1977
Creator: Aggus, J R; Edwards, D Jr; Halama, H J & Herrera, J C
Partner: UNT Libraries Government Documents Department

Diagnostics of inertial confinement fusion experiments

Description: The requirements of plasma temperature and particle energies are effectively the same for inertial confinement fusion, ICF, and magnetic containment fusion, MCF. The n/tau product must also be similar; however, in ICF we increase the density to achieve efficient fuel burn up. Reactor gain pellets are expected to require densities of up to 10/sup 4/ x liquid density of DT. This corresponds to n approximately 10/sup 26/ cm-/sup 3/. The dimensions of the compressed core are of the order of microns. Thus, the diagnostics problems in ICF is to measure plasmas at approximately 10/sup 8/ K, n approximately 10/sup 26/ cm-/sup 3/, on scale lengths of microns with time scales of picoseconds. In this paper we discuss the extensive diagnostics which we have developed to measure the performance of our laser irradiated targets.
Date: August 1, 1977
Creator: Ahlstrom, H.G.
Partner: UNT Libraries Government Documents Department

Laser fusion implosion and plasma interaction experiments

Description: Results related to the propagation, absorption and scattering of laser light by both spherical and planar targets are described. The absorption measurements indicate that for intensities of interest, inverse bremsstrahlung is not the dominant absorption mechanism. The laser light scattered by the plasma is polarization dependent and provides evidence that Brillouin scattering and resonance absorption are operative. Special diagnostics have been designed and experiments have been performed to elucidate the nature of these two processes. Implosion results on glass microshell targets filled with DT gas are also summarized. These experiments are for targets intentionally operated in the portion of parameter space characteristic of exploding pusher events. Experiments have been performed over a yield range from 0 to 10/sup 9/ neutrons per event. It is shown how this data can be normalized with a simple scaling law.
Date: August 1, 1977
Creator: Ahlstrom, H.G.
Partner: UNT Libraries Government Documents Department

Laser fusion implosion and target interaction physics

Description: Laser plasma experiments at the Lawrence Livermore Laboratory have progressed very rapidly and have achieved new milestones in both the implosion and DT gain in laser fusion targets. New diagnostic methods were also developed for determining the state of the compressed fuel and the plasma processes which are occurring in the absorption and scattering of the laser light incident on the laser fusion pellets. A review of the program is given. (MOW)
Date: May 19, 1977
Creator: Ahlstrom, Harlow G. & Nuckolls, John H.
Partner: UNT Libraries Government Documents Department