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Health and Safety Laboratory Environmental Quarterly Report: October 1, 1977, Appendix

Description: Report that presents information regarding chemical and radioactive pollution in the world. This appendix includes a quarterly report of the deposition of strontium-90 and measurements of radionuclides and lead in surface air, milk, and tapwater. Includes a table of radionuclides.
Date: October 1, 1977
Creator: HASL (New York, N.Y.)
Partner: UNT Libraries Government Documents Department

Fluorimetric Determination of Uranium in Shales, Lignites, and Monazites After Alkali Carbonate Separation

Description: Abstract: "Comparative data are presented on separations of microgram amounts of uranium from milligram amounts of various metal ions with Na2Co3-K2CO3, Na2CO3-K2CO3-H2O2, and Na2CO3-NaClO. The Na2CO3-K2CO3 separation procedure is applied to the analysis of shales, lignites, and monazites. This method will determine as little as 0.001 percent uranium in shales and lignites and 0.01 percent uranium in monazites."
Date: October 1951
Creator: Grimaldi, F. S. & Guttag, Norma S.
Partner: UNT Libraries Government Documents Department

Calculated Burnups and Fluences for Experimental Fuel Elements Irradiated in EBR-II Runs 5-55B

Description: A procedure is described for calculation of burnups and fluences at any point in a subassembly in EBR-II runs 5-55B. The calculations are performed by the BRN program package and require data generated for any element in the highly inhomogeneous fueled experimental subassemblies is the most important application of the pointwise capability. Tables allow calculation of burnup and fluences for any element in such a subassembly.
Date: October 1976
Creator: Kucera, D. A. & Meneghetti, D.
Partner: UNT Libraries Government Documents Department

One-Dimensional Drift-Flux Model and Constitutive Equations for Relative Motion Between Phases in Various Two-Phase Flow Regimes

Description: In view of the practical importance of the drift-flux model for two-phase flow analysis in general and in the analysis of nuclear-reactor transients and accidents in particular, the kinematic constitutive equation for the drift velocity has been studied for various two-phase flow regimes. The constitutive equation that specifies the relative motion between phases in the drift-flux model has been derived by taking into account the interfacial geometry, the body-force field, shear stresses, and the interfacial momentum transfer, since these macroscopic effects govern the relative velocity between phases. A comparison of the model with various experimental data over various flow regimes and a wide range of flow parameters shows a satisfactory agreement.
Date: October 1977
Creator: Ishii, M.
Partner: UNT Libraries Government Documents Department

Cracking and Healing Behavior of UO2 as Related to Pellet-Cladding Mechanical Interaction : Interim Report, July 1976

Description: A direct-electrical-heating apparatus has been designed and fabricated to investigate those nuclear-fuel-related phenomena involved in the gap closure-bridging annulus formation mechanism that can be reproduced in an out-of-reactor environment. Prototypic light-water-reactor uranium dioxide fuel-pellet temperature profiles have been generated utilizing high flow rates (approximately 700 liters/min) of helium coolant gas, and a re-circulating system has been fabricated to permit tests of up to 1000 h. Simulated light-water-reactor single- and multiple-thermal-cycle experiments will be conducted on both unclad and ceramic (fused silica) clad uranium dioxide pellet stacks. A laser dilatometer is used to measure pellet dimensional increase continuously during thermal cycling. Acoustic emissions from thermal-gradient cracking have been detected and correlated with crack length and crack area. The acoustic emissions are monitored continuously to provide instantaneous information about thermal-gradient cracking. Post-test metallography and fracture-mechanics measurements are utilized to characterize cracking and crack healing.
Date: October 1976
Creator: Kennedy, C. R.; Yaggee, F. L.; Voglewede, J. C.; Kupperman, D. S.; Wrona, B. J.; Ellingson, W. A. et al.
Partner: UNT Libraries Government Documents Department

Fission-Product Releases to the Primary System of EBR-II, January 1974-March 1975

Description: Seven releases of fission products occurred in EBR-II from January 1974 to March 1975 - - five from mixed-oxide elements and two from sodium-bonded driver-fuel elements. Four releases were from elements that contained a xenon tag, which aided considerably in locating three of the elements; data from the fourth element allowed estimation of changes of tag composition with reactor exposure. Rapid release of fission from two breached mixed-oxide elements caused the reactor to trip because of increased delayed-neutron activity, the first time such behavior has been observed. Identification of a subassembly of Mark-1A driver-fuel elements was complicated by multiple failure of its untagged elements during the diagnosis period. Several of these elements had some exposed fuel in the core, which was the likely cause of increasing delayed-neutron signals from the subassembly.
Date: October 1976
Creator: So, B. Y. C.; Lambert, J. D. B.; Johnson, D. L.; Ebersole, E. R. & Brunson, G. S.
Partner: UNT Libraries Government Documents Department

An Analysis of the High-Temperature Particulate Collection Problem

Description: Particulate agglomeration and separation at high temperatures and pressures are examined, with particular emphasis on the unique features of the direct-cycle application of fluidized-bed combustion. The basic long-range mechanisms of aerosol separation are examined, and the effects of high temperature and high pressure on usable collection techniques are assessed. Primary emphasis is placed on those avenues that are not currently attracting widespread research. The high-temperature, particulate-collection problem is surveyed, together with the peculiar requirements associated with operation of turbines with particulate-bearing gas streams.
Date: October 1977
Creator: Razgaitis, Richard
Partner: UNT Libraries Government Documents Department

A Survey of Numerical Methods for Hydraulic Transients

Description: The finite difference methods of Lax, Lax-Wendroff (two-step), donor cell type and finite-element method using Galerkin procedure with B-splines as approximating functions are compared with the method of characteristics for the solution of water-hammer transients as typified by valve closure problems. From the point of view of accuracy, the two-step Lax-Wendroff method and the method of characteristics are comparable and produce the best results. The Lax methods fair worst. The donor cell type and the Galerkin procedure with quadratic B-spline basis as approximating functions display roughly the same accuracy. From the comparison presented, it appears that Galerkin technique offers no substantial advantage over the other finite-difference methods except that of ease in handling boundary conditions as compared to finite-difference methods.
Date: October 1977
Creator: Leaf, G. K. & Chawla, T. C.
Partner: UNT Libraries Government Documents Department

Computation of the Weight Function from a Stress Intensity Factor

Description: A simple representation for the crack-face displacement is employed to compute a weight function solely from stress intensity factors for a reference loading configuration. Crack face displacements given by the representation are shown to be in good agreement with analytical results for cracked tensile strips, and stress intensity factors computed from the weight function agree well with those for edge cracks in half planes, radial cracks from circular holes, and radially cracked rings. The technique involves only simple quadrature and its efficacy is demonstrated by the example computations. The weight function for a corner crack in an LMFBR hexagonal sub-assembly duct is constructed from stress-intensity-factor results for the uniformly over-pressurized case, and it is shown how this may be used to determine the stress intensity factors.
Date: October 1977
Creator: Petroski, H. J. & Achenbach, J. D.
Partner: UNT Libraries Government Documents Department

Materials Technology for Coal-Conversion Processes Quarterly Report: April-June 1980

Description: Quarterly report on the activities of the Argonne National Laboratory Materials Science Division regarding studies on ceramic (refractory) and metallic materials presently being used or intended for use in coal-conversion processes. The program entails research in the fields of nondestructive testing and failure analysis, together with studies of erosive wear, corrosion, and refractory degradation.
Date: October 1980
Creator: Ellingson, W. A.
Partner: UNT Libraries Government Documents Department

Autoradiographic Technique for Rapid Inventory of Plutonium-Containing Fast Critical Assembly Fuel

Description: A nondestructive autoradiographic technique is described which can provide a verification of the piece count and the plutonium content of plutonium-containing fuel elements. This technique uses the spontaneously emitted gamma rays from plutonium to form images of fuel elements on photographic film. Autoradiography has the advantage of providing an inventory verification without the opening of containers or the handling of fuel elements. Missing fuel elements, substitution of nonradioactive material, and substitution of elements of different size are detectable. Results are presented for fuel elements in various storage configurations and for fuel elements contained in a fast critical assembly.
Date: October 1977
Creator: Brumbach, S. B. & Perry, R. B.
Partner: UNT Libraries Government Documents Department

Reactor Safety Study: An Assessment of Accident Risks in U.S. Commercial Nuclear Power Plants, Appendix 1

Description: From introduction: In conventional safety analyses, a suitable design basis, including redundancy, is specified to assure a minimum level of operability of ESFs, and the likelihood or consequences of total failure of ESFs are not considered further. In this study all failures are considered possible, but appropriate probabilities are assigned to them. Thus, many potential accident sequences are described in the following discussions as if they will surely occur, with no reservations expressed as to their likelihood or significance. However, most of these sequences have such low probability that they do not contribute to the overall risk from reactor accidents. In fact, in order to make an overall risk assessment, a major task of this study was to identify the sequences that are the dominant contributors to risk. In this study the initial failures or initiating events that could lead to significant consequences were examined to varying degrees. Those that seemed to contribute significantly to potential risks were analyzed in considerable detail; those that did not, received less detailed consideration. This is discussed more fully in section 3 of this appendix.
Date: October 1975
Creator: U.S. Nuclear Regulatory Commission
Partner: UNT Libraries Government Documents Department

Reactor Safety Study: An Assessment of Accident Risks in U.S. Commercial Nuclear Power Plants, Appendices 3 and 4

Description: From section 1: In the quantitative system probability estimates performed in this study, component behavior data in the form of failure rates and repair times are required as inputs to the system models. Since the goal of this study is risk assessment, as opposed to reliability analysis, larger errors (e.g. order of magnitude type accuracy) can be tolerated in the quantified results. This has important implications on the treatment of available data. In standard reliability analysis, point values (i.e., "best-estimates") are generally used for both data and results in quantifying the system model. In risk assessment, since results accurate to about an order of magnitude are sufficient, data and results using random variable and probabilistic approaches, can be usefully employed. The base of applicable failure rate data is thus significantly broadened since data with large error spreads and uncertainties can now be utilized. The data and associated material that were assembled for use in this study and that are presented here are to be used in the random variable framework (which will be described). The data and the accompanying framework are deemed sufficient for the study's needs. Care must be taken, however, since this data may not be sufficiently detailed, or accurate enough for use in general quantitative reliability models.
Date: October 1975
Creator: U.S. Nuclear Regulatory Commission
Partner: UNT Libraries Government Documents Department

Three-Dimensional Thermal-Neutron Radiography

Description: Three-dimensional radiographic methods provide a means of determining the depth of defect indications and minimizing the confusion that results from overlapping images of structures at various depths in an object. One method of obtaining and displaying three-dimensional radiographic images is multiple-film laminagraphy, i.e., a series of radiographic films taken at different orientations can be viewed superimposed to present a sharply focused image of any desired object plane. Methods that use multiple-film laminagraphy for three-dimensional thermal-neutron images will be described.
Date: October 1976
Creator: Berger, H. & Reimann, K. J.
Partner: UNT Libraries Government Documents Department

Foundation Grouting Practices at Corps of Engineers Dams

Description: The purpose of the assessment is to provide background information on the Corps' practices, identify shortcomings in specifications, estimates, grout placement techniques, and, in general, to determine the effectiveness of the Corps' grouting programs. The report reviews past grouting projects and describes the planning, execution, and performance evaluation of the programs.
Date: October 1984
Creator: Albritton, John; Jackson, Lawson & Bangert, Robert
Partner: UNT Libraries Government Documents Department

Plane-Strain Stress Intensity Factors for Cracked Hexagonal Subassembly Ducts

Description: Plane-strain stress intensity factors for a pressurized hexagonal subassembly duct with a crack in a corner or midflat are presented in convenient graphical form for representative LMFBR hexcan dimensions. Corner-crack calibrations based on several different models of the round hexcan corner are determined first in order to bound the stress intensity factor. A subsequent finite-element analysis of a uniformly pressurized hexcan with a corner crack gives accurate data for the stress intensity factor from which a weight function for this geometry may be constructed. The effects of different numbers of cracks, different locations for cracks, and different loading modes are discussed briefly, and some comments are made on the application of linear elastic fracture mechanics to cracked hexagonal ducts that have suffered a high degree of irradiation embrittlement.
Date: October 1977
Creator: Petroski, H. J.; Glazik, J. L. & Achenbach, J. D.
Partner: UNT Libraries Government Documents Department