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Analysis of cracked core spray piping from the Quad Cities Unit 2 boiling water reactor (open access)

Analysis of cracked core spray piping from the Quad Cities Unit 2 boiling water reactor

The results of a metallurgical analysis of leaking cracks detected in the core spray injection piping of Commonwealth Edison Company's Quad Cities Unit 2 Boiling Water Reactor are described. The cracks were present in a welded 105/sup 0/ elbow assembly in the line, and were found to be caused by intergranular stress corrosion cracking associated with the probable presence of dissolved oxygen in the reactor cooling water and the presence of grain boundary sensitization and local residual stresses induced by welding. The failure is unusual in several respects, including the very large number of cracks (approximately 40) present in the failed component, the axial orientation of the cracks, and the fact that at least one crack completely penetrated a circumferential weld. Virtually all of the cracking occurred in forged material, and the microstructural evidence presented suggests that the orientation of the cracks was influenced by the presence of axially banded delta ferrite in the microstructure of the forged components.
Date: September 1, 1982
Creator: Diercks, D. R. & Gaitonde, S. M.
System: The UNT Digital Library
Thousand TeV in the center of mass: introduction to high-energy storage rings (open access)

Thousand TeV in the center of mass: introduction to high-energy storage rings

The lecture discusses, in a pedagogic way, a hypothetical 500 TeV proton storage ring accelerator. It gives machine parameters, discusses linear optics and betatron motions, surveys questions of errors, tolerances and nonlinear resonances, and discusses some of the demands on the detection apparatus, especially the apparent inevitability of multiple interactions per bunch crossing. (GHT)
Date: September 1, 1982
Creator: Bjorken, J. D.
System: The UNT Digital Library
Pyrochemical processing of plutonium. Technology review report (open access)

Pyrochemical processing of plutonium. Technology review report

Non-aqueous processes are now in routine use for direct conversion of plutonium oxide to metal, molten salt extraction of americium, and purification of impure metals by electrorefining. These processes are carried out at elevated temperatures in either refractory metal crucibles or magnesium-oxide ceramics in batch-mode operation. Direct oxide reduction is performed in units up to 700 gram PuO/sub 2/ batch size with molten calcium metal as the reductant and calcium chloride as the reaction flux. Americium metal is removed from plutonium metal by salt extraction with molten magnesium chloride. Electrorefining is used to isolate impurities from molten plutonium by molten salt ion transport in a controlled potential oxidation-reduction cell. Such cells can purify five or more kilograms of impure metal per 5-day electrorefining cycle. The product metal obtained is typically > 99.9% pure, starting from impure feeds. Metal scrap and crucible skulls are recovered by hydriding of the metallic residues and recovered either as impure metal or oxide feeds.
Date: September 8, 1982
Creator: Coops, M.S.; Knighton, J.B. & Mullins, L.J.
System: The UNT Digital Library
High-temperature oxidation of Zircaloy in hydrogen-steam mixtures. [PWR; BWR] (open access)

High-temperature oxidation of Zircaloy in hydrogen-steam mixtures. [PWR; BWR]

Oxidation rates of Zircaloy-4 cladding tubes have been measured in hydrogen-steam mixtures at 1200 to 1700/sup 0/C. For a given isothermal oxidation temperature, the oxide layer thicknesses have been measured as a function of time, steam supply rate, and hydrogen overpressure. The oxidation rates in the mixtures were compared with similar data obtained in pure steam and helium-steam environments under otherwise identical conditions. The rates in pure steam and helium-steam mixtures were equivalent and comparable to the parabolic rates obtained under steam-saturated conditions and reported in the literature. However, when the helium was replaced with hydrogen of equivalent partial pressure, a significantly smaller oxidation rate was observed. For high steam-supply rates, the oxidation kinetics in a hydrogen-steam mixture were parabolic, but the rate was smaller than for pure steam or helium-steam mixtures. Under otherwise identical conditions, the ratio of the parabolic rate for hydrogen-steam to that for pure steam decreased with increasing temperature and decreasing steam-supply rate.
Date: September 1, 1982
Creator: Chung, H. M. & Thomas, G. R.
System: The UNT Digital Library
Symposium on unsaturated flow and transport modeling (open access)

Symposium on unsaturated flow and transport modeling

This document records the proceedings of a symposium on flow and transport processes in partially saturated groundwater systems, conducted at the Battelle Seattle Research Center on March 22-24, 1982. The symposium was sponsored by the US Nuclear Regulatory Commission for the purpose of assessing the state-of-the-art of flow and transport modeling for use in licensing low-level nuclear waste repositories in partially saturated zones. The first day of the symposium centered around research in flow through partially saturated systems. Papers were presented with the opportunity for questions following each presentation. In addition, after all the talks, a formal panel discussion was held during which written questions were addressed to the panel of the days speakers. The second day of the Symposium was devoted to solute and contaminant transport in partially saturated media in an identical format. Individual papers are abstracted.
Date: September 1, 1982
Creator: Arnold, E. M.; Gee, G. W. & Nelson, R. W. (eds.)
System: The UNT Digital Library
Recent advances in yeast molecular biology: recombinant DNA. [Lead abstract] (open access)

Recent advances in yeast molecular biology: recombinant DNA. [Lead abstract]

Separate abstracts were prepared for the 25 papers presented at a workshop focusing on chromosomal structure, gene regulation, recombination, DNA repair, and cell type control, that have been obtained by experimental approaches incorporating the new technologies of yeast DNA transformation, molecular cloning, and DNA sequence analysis. (KRM)
Date: September 1, 1982
Creator: unknown
System: The UNT Digital Library
Infrared-emission spectroscopy of CO on Ni (open access)

Infrared-emission spectroscopy of CO on Ni

We report the first observation of thermally emitted infrared radiation from vibrational modes of molecules adsorbed on clean, single-crystal metal surfaces. The observation of emission from CO adsorbed on Ni demonstrates the surface sensitivity of a novel apparatus for infrared vibrational spectroscopy, with a resolution of 1 to 15 cm/sup -1/ over the frequency range from 330 to 3000 cm/sup -1/. A liquid-helium-cooled grating spectrometer measures the thermal radiation from a room-temperature, single-crystal sample, which is mounted in an ultrahigh-vacuum system. Measurements of frequencies and linewidths of CO on a single-crystal Ni sample, as a function of coverage, are discussed.
Date: September 1, 1982
Creator: Chiang, S.; Tobin, R.G. & Richards, P.L.
System: The UNT Digital Library
Survey of E-Division accelerators at the Lawrence Livermore National Laboratory (open access)

Survey of E-Division accelerators at the Lawrence Livermore National Laboratory

The Experimental Physics Division (E-Division) at the Lawrence Livermore National Laboratory conducts research in basic and applied nuclear and atomic physics and materials science. Most of the research within the Division utilizes one of three facilities: an intense 14-MeV neutron source, a 27-MeV cyclograaff (consisting of a 15-MeV cyclotron and a 6-MV tandem van de Graaff), and a 100-MeV electron linac. A brief description of each facility is presented with emphasis on the research capabilities presently available.
Date: September 30, 1982
Creator: Proctor, I.D.
System: The UNT Digital Library
Organics, soot, and ambient sulfate (open access)

Organics, soot, and ambient sulfate

Evidence is presented for significant local sulfate formation, the existence of a chemical link between ambient sulfate and organic particulate material is postulated, and a new SO/sub 2/ oxidation process by a reaction between organic products of incomplete combustion and SO/sub 2/ is described. Specifically, results of field studies on the relationship among sulfate, SO/sub 2/, and carbonaceous particles, speciation of sulfate and nitrogenous species, and laboratory results on certain aspects of SO/sub 2/ oxidation are presented. It is concluded that in highly polluted atmospheres, large concentrations of ambient sulfate can be produced by conversion of locally emitted SO/sub 2/ by a process that is largely independent of SO/sub 2/ but proportional to soot concentration. Ambient sulfate from many locations is found as anomalous ammonium sulfate where charged organic nitrogen complexes substitute for ammonium ions. Such sulfate is found when the aerosol is rich in organic constituents. The reaction between pyrolysis products of hydrocarbon fuels and SO/sub 2/ is an efficient mechanism for sulfate ion formation. This reaction is strongly dependent on combustion conditions.
Date: September 1, 1982
Creator: Novakov, T.
System: The UNT Digital Library
Dynamics of damped nuclear reactions (open access)

Dynamics of damped nuclear reactions

The nucleon-exchange model for damped nuclear reactions is briefly reviewed in the framework of macroscopic transport theory. Recent developments are discussed and some future directions indicated.
Date: September 1, 1982
Creator: Randrup, J.
System: The UNT Digital Library
ISAJET: a Monte Carlo event generator for pp and anti pp interactions. Version 3 (open access)

ISAJET: a Monte Carlo event generator for pp and anti pp interactions. Version 3

ISAJET is a Monte Carlo computer program which simulates pp and anti pp reactions at high energy. It can generate minimum bias events representative of the total inelastic cross section, high PT hadronic events, and Drell-Yan events with a virtual ..gamma.., W/sup + -/, or Z/sup 0/. It is based on perturbative QCD and phenomeno-logical models for jet fragmentation.
Date: September 1982
Creator: Paige, F. E. & Protopopescu, S. D.
System: The UNT Digital Library
Diagnostics in the Hostile Environments of a Prototype Fusion Reactor (open access)

Diagnostics in the Hostile Environments of a Prototype Fusion Reactor

The first lecture begins by reviewing the various facets of a thermonuclear-type plasma that will likely require special considerations or hardening of the applied diagnostic instrumentation. Several factors are necessary to adopt relatively standard plasma diagnostic techniques to function satisfactorily in the more hostile environment of a thermonuclear-type plasma. This lecture contains a listing of the various types of expected hardening requirements for a representative set of diagnostic instrumentation, including both on-line diagnostic instrumentation requirements for satisfactory operation and considerations to reduce integrated radiation damage sufficiently for a reasonable diagnostic lifetime. The second lecture in this series concerns several new diagnostics aimed specifically at measuring the plasma characteristics most appropriate to a thermonuclear-reactor-type plasma. This includes instrumentation needed to make quantitative energy-flow measurements during long-term operation with the expected high-input power sources, and locally very-high-wall power loadings. The second part of this lecture broadens diagnostics to include materials damage measurements needed for engineering design studies. This includes needed diagnostic instrumentation to assess first-wall damage, sputtering erosion at the walls (and high-power beam dumps), and radiation damage to components such as insulators.
Date: September 24, 1982
Creator: Osher, John E.
System: The UNT Digital Library
Modeled heating and surface erosion comparing motile (gas borne) and stationary (surface coating) inert particle additives (open access)

Modeled heating and surface erosion comparing motile (gas borne) and stationary (surface coating) inert particle additives

The unsteady, non-similar, chemically reactive, turbulent boundary layer equations are modified for gas plus dispersed solid particle mixtures, for gas phase turbulent combustion reactions and for heterogeneous gas-solid surface erosive reactions. The exterior (ballistic core) edge boundary conditions for the solutions are modified to include dispersed particle influences on core propellant combustion-generated turbulence levels, combustion reactants and products, and reaction-induced, non-isentropic mixture states. The wall surface (in this study it is always steel) is considered either bare or coated with a fixed particle coating which is conceptually non-reactive, insulative, and non-ablative. Two families of solutions are compared. These correspond to: (1) consideration of gas-borne, free-slip, almost spontaneously mobile (motile) solid particle additives which influence the turbulent heat transfer at the uncoated steel surface and, in contrast, (2) consideration of particle-free, gas phase turbulent heat transfer to the insulated surface coated by stationary particles. Significant differences in erosive heat transfer are found in comparing the two families of solutions over a substantial range of interior ballistic flow conditions. The most effective influences on reducing erosive heat transfer appear to favor mobile, gas-borne particle additives.
Date: September 27, 1982
Creator: Buckingham, A.C. & Siekhaus, W.J.
System: The UNT Digital Library
Database for nuclear-waste disposal for temperatures up to 300/sup 0/C (open access)

Database for nuclear-waste disposal for temperatures up to 300/sup 0/C

A computerized database is compiled of evaluated thermodynamic data for aqueous species associated with nuclear waste storage. The data are organized as hydrolysis and formation constants; solubilities of oxides and hydroxides; and, as Nernstian potentials. More emphasis is on stability constants. Coeffficients are given to calculate stability constants at various ionic strengths and to high temperatures. Results are presented as tables for selected species including uranium, amorphous silica and actinides.
Date: September 1, 1982
Creator: Phillips, S.L. & Silvester, L.F.
System: The UNT Digital Library
Effect of shape reactivity on the rod-ejection accident (open access)

Effect of shape reactivity on the rod-ejection accident

The shape reactivity has a significant influence on the rod ejection accident. After the control rod is fully ejected from the core, the neutron flux undergoes a large reduction at the ejected rod location. The corresponding effect on the control reactivity is comparable in magnitude to the Doppler reactivity, and makes a significant contribution to limiting the power excursion during the transient. The neglect of this effect in point kinetics and space time synthesis analyses of the rod ejection accident may account in part for the large degree of conservatism usually associated with these analyses.
Date: September 1, 1982
Creator: Neogy, P. & Carew, J.F.
System: The UNT Digital Library
SYNROC production using a fluid bed calciner (open access)

SYNROC production using a fluid bed calciner

SYNROC is a titanate-based ceramic developed for immobilization of high-level nuclear reactor wastes in solid form. Fluid-bed SYNROC production permits slurry drying, calcining and redox to be carried out in a single unit. We present results of studies from two fluid beds; the Idaho Exxon internally-heated unit and the externally-heated unit constructed at Lawrence Livermore National laboratory. Bed operation over a range of temperature, feed rate, fluidizing rate and redox conditions indicate that high density, uniform particle-size SYNROC powders are produced which facilitate the densification step and give HUP parts with dense, well-developed phases and good leaching characteristics. 3 figures, 3 tables.
Date: September 27, 1982
Creator: Ackerman, F. J.; Grens, J. Z.; Ryerson, F. J.; Hoenig, C. L.; Bazan, F. & Campbell, J. H.
System: The UNT Digital Library
Calculations of gas density in a closely-packed multi-channel electrostatic quadrupole (MESQ) array (open access)

Calculations of gas density in a closely-packed multi-channel electrostatic quadrupole (MESQ) array

As a part of our program for developing new accelerators for high-energy negative ion neutral beamlines, we have studied the pumping properties of a MESQ array such as might be interposed between the ion-source/pre-accelerator and a MESQ accelerator. The studies were performed using a two-and-a-half dimensional Monte Carlo code under the assumption of molecular flow, with pumping to be provided by cryopanels on either side of the array. The basic unit treated by the code was a unit cell which could be translated laterally or longitudinally to reproduce the full array. We have studied the behavior of the system as a function of electrode geometry, array size, and cryopanel position. It was found necessary to insert lateral baffles periodically to prevent downstream migration of the gas in the region between the outer edge of the MESQ array and the cryopanels.
Date: September 1, 1982
Creator: Burrell, C.F. & Goldberg, D.A.
System: The UNT Digital Library
EM study of the structure and composition of grain boundaries in (Mn,Zn)Fe/sub 2/O/sub 4/ (open access)

EM study of the structure and composition of grain boundaries in (Mn,Zn)Fe/sub 2/O/sub 4/

Electron diffraction and microscopy studies supplemented by electron spectroscopic techniques such as Auger electron spectroscopy and energy dispersive x-ray spectroscopy were used to characterize the nature of grain boundary segregation in commercial grade (Mn,Zn)Fe/sub 2/O/sub 4/ samples containing small quantities of CaO. Chemical analyses by AES and EDAX show an enrichment of Ca near the grain boundary region. Convergent beam electron diffraction experiments show that the crystal symmetry of the spinel structure is distorted in the vicinity of the grain boundary. In-situ heating experiments in HVEM show the existence of a disordered phase at the sintering temperature. Lorentz microscopy in TEM shows the interaction of magnetic domain wall motion with grain boundaries. These chemical and structural features are correlated with electrical resistivity and magnetic permeability of the ferrites. 4 figures.
Date: September 1, 1982
Creator: Lin, I.N.; Mishra, R.K. & Thomas, G.
System: The UNT Digital Library
Effect of capacitive stored energy on neutral-beam-accelerator performance (open access)

Effect of capacitive stored energy on neutral-beam-accelerator performance

The results of tests to determine the effects of capacitive stored energy (1/2 CV/sup 2/) on the performance of neutral-beam injectors are reported. Typical fault-current waveforms and methods to limit fault current are presented. Tests indicate that deterioration of performance is not only a function of peak stored energy but is also dependent on peak current and the characteristics of the breakdown.
Date: September 1, 1982
Creator: Owren, H. M.; Baker, W. R.; Berkner, K. H.; Hopkins, D. B. & Massoletti, D. J.
System: The UNT Digital Library
Nonisothermal effects during injection and falloff tests (open access)

Nonisothermal effects during injection and falloff tests

The results show that to correctly analyze pressure transients governed by a moving thermal front, the values used for the fluid properties must correspond to the temperature of the injected fluid. On the other hand, for pressure falloff tests and for injection tests conducted in a well cooled by previous injection or drilling, the physical properties of the in situ reservoir fluids must be used. It is also shown that the application of conventional isothermal methods for calculating skin values from injection and falloff data will give erroneous results. A new method is presented for calculating skin values from injection and falloff data that accurately corrects for nonisothermal effects. A number of detailed examples are given that illustrate the suggested method of analysis. The technique is applied to the analysis of injection test data from a well located in the East Mesa geothermal field in southern California.
Date: September 1, 1982
Creator: Benson, S.M. & Bodvarsson, G.S.
System: The UNT Digital Library
Testing quantum chromodynamics (open access)

Testing quantum chromodynamics

The difficulties in isolating specific QCD mechanisms which control hadronic phenomena, and the complications in obtaining quantitative tests of QCD are discussed. A number of novel QCD effects are reviewed, including heavy quark and higher twist phenomena, initial and final state interactions, direct processes, multiparticle collisions, color filtering, and nuclear target effects. The importance of understanding hadron production at the amplitude level is stressed.
Date: September 1, 1982
Creator: Brodsky, Stanley J.
System: The UNT Digital Library
Low-noise wide-band amplifiers for stochastic beam cooling experiments (open access)

Low-noise wide-band amplifiers for stochastic beam cooling experiments

Noise characteristics of the continuous-wave wide-band amplifier systems for stochastic beam cooling experiments are presented. Also, the noise performance, bandwidth capability and gain stability of components used in these amplifiers are summarized and compared in the 100 MHz to 40 GHz frequency range. This includes bipolar and field-effect transistors, parametric amplifier, Schottky diode mixer and maser. Measurements of the noise characteristics and scattering parameters of variety GaAs FETs as a function of ambient temperature are also given. Performance data and design information are presented on a broadband 150-500 MHz preamplifier having noise temperature of approximately 35/sup 0/K at ambient temperature of 20/sup 0/K. An analysis of preamplifier stability based on scattering parameters concept is included.
Date: September 5, 1982
Creator: Leskovar, B. & Lo, C.C.
System: The UNT Digital Library
Tests with Inconel 600 to obtain quantitative stress-corrosion cracking data for evaluating service performance. [PWR] (open access)

Tests with Inconel 600 to obtain quantitative stress-corrosion cracking data for evaluating service performance. [PWR]

Inconel 600 tubes in pressurized water reactor (PWR) steam generators form a pressure boundary between radioactive primary water and secondary water which is converted to steam and used for generating electricity. Under operating conditions the performance of alloy 600 has been good, but with some occasional small leaks resulting from stress corrosion cracking (SCC), related to the presence of unusually high residual or operating stresses. The suspected high stresses can result from either the deformation of tubes during manufacture, or distortion during abnormal conditions such as denting. The present experimental program addresses two specific conditions, i.e., (1) where deformation occurs but is no longer active, such as when denting is stopped and (2) where plastic deformation of the metal continues, as would occur during denting. Laboratory media consist of pure water as well as solutions to simulate environments that would apply in service; tubing from actual production is used in carrying out these tests. The environments include both normal and off chemistries for primary and secondary water. The results reported here were obtained in several different tests. The main ones are (1) split tube reverse U-bends, (2) constant extension rate tests (CERT), and (3) constant load. The temperature range covered …
Date: September 1, 1982
Creator: Bandy, R. & van Rooyen, D.
System: The UNT Digital Library
Review of plutonium process chemistry at Rocky Flats (open access)

Review of plutonium process chemistry at Rocky Flats

Plutonium metal scrap, oxide, and other residues are processed at Rocky Flats using both pyrochemical and aqueous methods. The pyrochemical processes currently in production include electrorefining, fluorination, hydriding, molten salt extraction (MSE), calcination, and reduction operations. Aqueous processing and waste-treatment methods involve nitric acid dissolution, ion exchange, solvent extraction, and precipitation techniques. An overview of the chemistry involved in these operations will be given. Research in progress to improve these operations, or develop new processes, will also be presented.
Date: September 1, 1982
Creator: Baldwin, C.E. & Navratil, J.D.
System: The UNT Digital Library