WELDING AND BRAZING OF HIGH-TEMPERATURE RADIATORS AND HEAT EXCHANGERS (open access)

WELDING AND BRAZING OF HIGH-TEMPERATURE RADIATORS AND HEAT EXCHANGERS

Procedures were developed for fabricating highperformance radiators and heat exchangers for the Aircraft Nuclear Propulsion (ANP) Program. These components, which contain multitudes of tube-to-tube sheet and tube-to-fin joints, are similar in design to those under consideration for a variety of space vehicle applications. In order to ensure reliability of the tube-to-tube sheet joints, techniques producing welds of extremely high quality were used and back brazing of the welds with a suitable alloy was incorporated. High-temperature brazing was also incorporated to attach high-conductivity fins to Inconel tubes in the radiators. The selection of a suitable brazing alloy for these applications was dependent upon several factors, including corrosion and oxidation resistance, flow point, and mechanical properties. A Ni- Si-B alloy was found to be adequate from all these considerations. Special brazing procedures were developed to obtain satisfactory flowability of this brazing alloy on tube-to-fin joints. The suitability of these fabrication procedures for the very stringent service conditions to which the radiators and heat exchangers were subjected was demonstrated by testing full-size components under operating conditions. (auth)
Date: February 20, 1962
Creator: Slaughter, G.M. & Patriarca, P.
Object Type: Report
System: The UNT Digital Library
Near Term Hybrid Passenger Vehicle Development Program. Phase I, Final report. Appendix A: mission analysis and performance specification studies. Volume I (open access)

Near Term Hybrid Passenger Vehicle Development Program. Phase I, Final report. Appendix A: mission analysis and performance specification studies. Volume I

Studies are described which were performed for the Near Term Hybrid Vehicle program to determine passenger car usage patterns and to correlate these trip mission characteristics with vehicle design and performance specifications. (LCL)
Date: April 20, 1979
Creator: Traversi, M. & Barbarek, L.A.C.
Object Type: Report
System: The UNT Digital Library
Mixing and Evaporation in a Packed Vessel (open access)

Mixing and Evaporation in a Packed Vessel

In connection with an evaluation of the operability of a 36-inch diameter remote evaporator at the Idaho Chemical Processing Plant that was to be packed with a corrosionresistant neutron-poison packing for criticality control, an investigation in a 30-inch diameter vessel proved that air sparging effectively mixes solutions. The data showed that at similar spar;e rates the presence of the packing caused an increase in the time needed for complete mixing. The investigation showed that solutions are readily evaporated in spite of the presence of packing in the tank. (auth)
Date: September 20, 1961
Creator: Cederberg, C. K. & Buckham, J. A.
Object Type: Report
System: The UNT Digital Library
Repair Welding of Fusion Reactor Components (open access)

Repair Welding of Fusion Reactor Components

Recent experimental investigations indicate that the repair welding of irradiated materials containing greater than 1 to 2.5 appm helium leads to catastrophic cracking in the heat affected zone of the weld. The high temperatures and cooling tensile stresses which occur during the welding process lead to enhanced helium bubble growth in the heat affected zone region, resulting in catastrophic cracking upon cooling. An investigation is proposed which seeks to determine the effect of stress state on the helium bubble growth process and develop engineering modifications to the welding process based upon this understanding in an attempt to alleviate or eliminate the weld cracking problem in type 316 stainless steel materials.
Date: May 20, 1992
Creator: Chin, Bryan A.
Object Type: Report
System: The UNT Digital Library
Effect of Heat Flux on the Corrosion of Aluminum by Water. Part Iii. Final Report on Tests Relative to the High-Flux Isotope Reactor (open access)

Effect of Heat Flux on the Corrosion of Aluminum by Water. Part Iii. Final Report on Tests Relative to the High-Flux Isotope Reactor

The effect of very high heat fluxes on the corrosion of 1100 and 6061 aluminum alloys by water was investigated. The test conditions generally simulated those expected to exist during operation of the High-Flux lsotope Reactor. At heat fluxes between 1 and 2 x l0/sup 6/ Btu/hr-ft/sup 2/ and with coolant temperatures and velocities in the ranges of 13l to 250 deg F and 3l to 51 fps, respectively, a layer of boehmite ( alpha Al/sub 2/O/sub 3/- H/sub 2/0), which has low thermal conductivity, formed on the water-cooled aluminum surfaces during test. When only relatively thin films formed, the boehmite adhered tightly to the aluminum, but in those cases where relatively thick films formed, some boehmite spontaneously spalled from the surface. The rate at which the boehmite formed on the surface (and consequently the rate at which the aluminum temperature increased) was a function of the temperature at the specimen-water interface and the pH of the coolant. The lower the temperature and the lower the pH (in the range of 5.0 to 6.5 with HNO/sub 3/), the lower the rate of corrosion- product formation. Within the ranges investigated, pressure and flow rate were without effect, and the same results …
Date: December 20, 1961
Creator: Griess, J. C.; Savage, H. C.; Rainwater, J. G.; Mauney, T. H. & English, J. L.
Object Type: Report
System: The UNT Digital Library
Tellurium interference in /sup 129/I activation analysis (open access)

Tellurium interference in /sup 129/I activation analysis

Measurement of /sup 129/I at low levels is required for effluent control, environmental assessment and tracer studies in the natural environment. Low level /sup 129/I analysis has also been used for measurement of natural-fission-produced /sup 129/I in minerals and ores as well as meteorites. The most sensitive method for /sup 129/I measurements is neutron activation analysis of iodine separated from a suitable sample. Minimum sample processing prior to neutron activation is desirable in order to reduce chances of sample contamination with uranium or /sup 129/I. A potential interference in the activation analysis method is the production of /sup 129/I (/sup 130/I) from Te impurities in the irradiated ampoule. Procedures have been developed and applied to measurement of the magnitude of the potential Te interference. One-tenth of a microgram of Te in the irradiated ampoule is sufficient to produce interference in the analysis. This is detectable by either radiochemical Te measurements or by /sup 131/I detection in the iodine fraction from the irradiated ampoule. This paper discusses the procedures and results of Te interference studies in /sup 129/I activation analysis. The interference was found to be insignificant for most analyses. 5 tables.
Date: September 20, 1979
Creator: Kaye, J. H.; Brauer, F. P. & Strebin, Jr., R. S.
Object Type: Article
System: The UNT Digital Library
Cross Sections for X-Ray Photoelectron-Induced Desorption of Hydrogen Ions From Metal Surfaces (open access)

Cross Sections for X-Ray Photoelectron-Induced Desorption of Hydrogen Ions From Metal Surfaces

We have measured the cross sections for x-ray photoelectron-induced desorption of hydrogen ions from beryllium, carbon, aluminum, tantalum, and gold surfaces. This report describes the results of the cross-section measurements, and discusses a time-of-flight technique that allows the determination of ionic-desorption cross sections as small as 10/sup -25/ cm/sup 2/ per photoelectron. 19 refs., 7 figs.
Date: September 20, 1985
Creator: Kinney, J. H.; Siekhaus, W. J. & Anderson, R. A.
Object Type: Report
System: The UNT Digital Library
Development of passive electronic components for instrumentation of improved geothermal logging tools and components. Annual progress report (open access)

Development of passive electronic components for instrumentation of improved geothermal logging tools and components. Annual progress report

Short term objectives for well-logging instrumentation are circuits which can operate at temperatures in the range 275/sup 0/C to 350/sup 0/C; the medium term goal is operation up to 500/sup 0/C, and the long term goal is to achieve operation at 1000/sup 0/C. It is apparent that useful electronic circuits will require the combination of both passive components and active devices. In order to meet the compatibility requirements, the basic technology which has been selected in this project is the chemical vapor deposition of metal interconnections, resistor material, dielectric material and passivating material. It is to be emphasized that this is a thin-film, not thick-film, technology which is compatible with the processing methods used in fabricating either semiconductor or integrated thermionic devices, and produces components which are electrically compatible with those devices. The investigation in this project is primarily directed toward tungsten metallization, tungsten-silicon resistors, and silicon nitride dielectric and passivation.
Date: October 20, 1977
Creator: Raymond, L.S.; Hamilton, D.J. & Kerwin, W.J.
Object Type: Report
System: The UNT Digital Library
In Vivo Gamma Lung Measurements--a Mathematical Model (open access)

In Vivo Gamma Lung Measurements--a Mathematical Model

A low-background facility is described for rneasuring lung burdens of U, Th, and other nuclides in vivo. Problems associated with this method of radiation measurement are discussed. A mathennatical, computer-oriented simulation was devised to gain insight into the relation of the net observed radiation spectrum to the burden of radioactivity in the body or its organs. Chest cavities for persons of three sizes were synthesized in a three-coordinate space comprised of one-inch cubes and including a 9-in.-diameter crystal detector. Data, describing the tissue composition of each cube in the body and the characteristic radiation attenuation for each tissue-type, were coded for use with a program on a high-speed digital computer. Efficiencies for measuring radiation emitted by numerous point sources of enriched uranium were calculated. Data on in vivo measurement efficiency were obtained assuming uniform distribution of radioactive material throughout the lungs and also for nonuniform deposits. The effects of individual size and geometry, and of detector position on the measurement efficiency were determined for these twvo categories and radiation flux distributions on the detector face were computed in some cases. Data are appended and a flow diagram of the computer program is included. (C.H.)
Date: October 20, 1961
Creator: Ammann, P. R.; Wilson, C. W. & Mohr, C. M.
Object Type: Report
System: The UNT Digital Library
Computed and experimental interactions between eddy structure and dispersed particles in developing free shear layers (open access)

Computed and experimental interactions between eddy structure and dispersed particles in developing free shear layers

We are investigating the interactive process between turbulent flow and dispersed phase particles. We are focusing on the mechanisms that appear to result in a reduction of local turbulent intensity and a corresponding reduction in wall heat transfer and subsequent wall erosion in turbulent solid propellant combustion flow. We apply computational simulations and physical experiments specialized to a developing free shear layer over a rearward facing step and over a parallel splitter plate. The flow configuration evolves in a two-dimensional, steady, combustion and non-combustion turbulent free shear mixing region, with and without particle additives. The computational simulations combine three basic components: gas phase Navier-Stokes solutions, Lagrange particle field solutions and a Monte Carlo technique for the random encounters, forces and accelerations between the two fields. We concentrate here on relatively large sized additive particles (of the order of tens of microns to 100 microns mean diameter). We examine their apparent influence in breaking up the larger, energy bearing eddy structures into smaller structures which are more readily dissipated.
Date: May 20, 1982
Creator: Buckingham, A. C.; Siekhaus, W. J.; Keller, J. O.; Ellzey, J.; Hubbard, G. & Daily, J. W.
Object Type: Article
System: The UNT Digital Library
Exact calculations of nuclear-recoil energies from prompt gamma decays resulting from neutron capture (open access)

Exact calculations of nuclear-recoil energies from prompt gamma decays resulting from neutron capture

The results of an accurate determination of the recoil spectrum from (n, ..gamma..) reactions in molybdenum are presented. The recoil spectrum has been calculated from nuclear level structure data and measured branching ratios. Angular correlations between successive gammas have been accounted for using the standard theoretical techniques of Racah algebra and the density matrix formalism.
Date: July 20, 1981
Creator: Kinney, J.H.
Object Type: Report
System: The UNT Digital Library
Coal fracture measurements using in situ electrical methods: preliminary results (open access)

Coal fracture measurements using in situ electrical methods: preliminary results

None
Date: November 20, 1974
Creator: Lytle, R.J.; Laine, E.F. & Lager, D.L.
Object Type: Report
System: The UNT Digital Library
SEPARATION OF TRANSPLUTONIUMS FROM LANTHANIDES BY TERTIARY AMINE EXTRACTION (open access)

SEPARATION OF TRANSPLUTONIUMS FROM LANTHANIDES BY TERTIARY AMINE EXTRACTION

None
Date: December 20, 1961
Creator: Baybarz, R.D. & Weaver, B.
Object Type: Report
System: The UNT Digital Library
Noise Considerations in Nuclear Pulse Amplifiers (open access)

Noise Considerations in Nuclear Pulse Amplifiers

The effects of certain pulse-shaping networks on the signal-to-noise ratio of a nuclear pulse amplifier were considered. The shaping networks discussed are: equal RC-integrating and RC-differentiating time constant, single- delay-line clipper and RC integrator, and doubledelay-line clipper and RC integrator. The effects of these networks on the signal, when high count rates and overload pulses are present, were also considered. Equations and curves were developed for the energy resolution (signal-tonoise ratio) and resolving time (related to the ability to operate at high counting rates) of the networks. Experimental results are shown for the energy resolution of the types of pulse- shaping networks considered. (auth)
Date: December 20, 1961
Creator: Landis, D. A.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Internal dosimetry technical basis manual (open access)

Internal dosimetry technical basis manual

The internal dosimetry program at the Savannah River Site (SRS) consists of radiation protection programs and activities used to detect and evaluate intakes of radioactive material by radiation workers. Examples of such programs are: air monitoring; surface contamination monitoring; personal contamination surveys; radiobioassay; and dose assessment. The objectives of the internal dosimetry program are to demonstrate that the workplace is under control and that workers are not being exposed to radioactive material, and to detect and assess inadvertent intakes in the workplace. The Savannah River Site Internal Dosimetry Technical Basis Manual (TBM) is intended to provide a technical and philosophical discussion of the radiobioassay and dose assessment aspects of the internal dosimetry program. Detailed information on air, surface, and personal contamination surveillance programs is not given in this manual except for how these programs interface with routine and special bioassay programs.
Date: December 20, 1990
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Facile reaction/extraction of coal with supercritical fluids. Quarterly technical progress report, January 1-March 31, 1984 (open access)

Facile reaction/extraction of coal with supercritical fluids. Quarterly technical progress report, January 1-March 31, 1984

Arylmethyl phenyl ethers undergo competing reactions when treated with Lewis acids in benzene solvent. Apparently, benzene is insufficiently reactive to compete with intramolecular (intrapolymer) nucleophiles and, consequently, no increase in solubility accompanies the cleavages of ether links upon addition of benzene. When better nucleophiles, naphthalene and phenanthene, are provided, carbonium ions generated from ether cleavages are capped and the product is lower in molecular weight and more soluble. It is worth noting that the naphthalene (k/sub rel/ = 300) is nearly as good a trap as the phenol (k/sub rel/ = 450). Since hydroxylic solvents will level the acid strength of BF/sub 3/ to that of ROBF/sub 3//sup -/H/sup +/ and hydrocarbons would not, the acid-catalyzed bond cleavages necessary for unlinking coal may in fact be faster in BF/sub 3/-arene than in BF/sub 3/-phenol. While we have not yet extended these results to coals, we believe that the combination of a relatively mild Lewis acid catalyst, BF/sub 3/, with a good carbonium ion trap, naphthalene, will allow selective cleavage and capping of aryl alkyl ether bonds. 3 references, 2 figures, 3 tables.
Date: April 20, 1984
Creator: Venier, C. G. & Squires, T. G.
Object Type: Report
System: The UNT Digital Library
MHD compressor---expander conversion system integrated with GCR inside a deployable reflector (open access)

MHD compressor---expander conversion system integrated with GCR inside a deployable reflector

This work originates from the proposal MHD Compressor-Expander Conversion System Integrated with a GCR Inside a Deployable Reflector''. The proposal concerned an innovative concept of nuclear, closed-cycle MHD converter for power generation on space-based systems in the multi-megawatt range. The basic element of this converter is the Power Conversion Unit (PCU) consisting of a gas core reactor directly coupled to an MHD expansion channel. Integrated with the PCU, a deployable reflector provides reactivity control. The working fluid could be either uranium hexafluoride or a mixture of uranium hexafluoride and helium, added to enhance the heat transfer properties. The original Statement of Work, which concerned the whole conversion system, was subsequently redirected and focused on the basic mechanisms of neutronics, reactivity control, ionization and electrical conductivity in the PCU. Furthermore, the study was required to be inherently generic such that the study was required to be inherently generic such that the analysis an results can be applied to various nuclear reactor and/or MHD channel designs''.
Date: April 20, 1989
Creator: Tuninetti, G. (Ansaldo S.p.A., Genoa (Italy). Research Div.); Botta, E.; Criscuolo, C.; Riscossa, P. (Ansaldo S.p.A., Genoa (Italy). Nuclear Div.); Giammanco, F. (Pisa Univ. (Italy). Dipt. di Fisica) & Rosa-Clot, M. (Florence Univ. (Italy). Dipt. di Fisica)
Object Type: Report
System: The UNT Digital Library
Energy Exchange Within Ecosystems Annual Report: 1976 (open access)

Energy Exchange Within Ecosystems Annual Report: 1976

None
Date: September 20, 1975
Creator: Gates, David M.
Object Type: Report
System: The UNT Digital Library
Administration of ORNL Research Reactors (open access)

Administration of ORNL Research Reactors

Organization of the ORNL Operations division for administration of the Oak Ridge Research Reactor, the Low Intensity Testing Reactor, and the Oak Ridge Graphite Reactor is described. (J.R.D.)
Date: August 20, 1962
Creator: Casto, W. R.
Object Type: Report
System: The UNT Digital Library
Leaching study of PNL 76-68 glass beads using the LLNL continuous-flow method and the PNL-modified IAEA method. Final report (open access)

Leaching study of PNL 76-68 glass beads using the LLNL continuous-flow method and the PNL-modified IAEA method. Final report

Lawrence Livermore National Laboratory (LLNL) has conducted a long-term single-pass continuous-flow (SPCF) leaching test of the glass waste form PNL 76-68. Leaching rates of Np, Pu, and various stable elements were measured at 25/sup 0/ and 75/sup 0/C with three different solutions and three different flow rates. The purposes of the study were: (1) to compare SPCF leaching results with the results of a modified IAEA leach test performed by Pacific Northwest Laboratories (PNL); (2) to establish elemental leach rates and their variation with temperature, flow rate and solution composition; and (3) to gain insight into the leaching mechanisms. The LLNL and PNL leach tests yielded results which appear to agree within experimental uncertainties. The magnitude of the leach rates determined for Np and the glass matrix elements is 10/sup -5/ grams of glass/cm/sup 2/ geometric solid surface area/day. The rates increase with temperature and with solution flow rate, and are similar in brine and distilled water but higher in a bicarbonate solution. Other cations exhibit somewhat different behavior, and Pu in particular yields a much lower apparent leach rate, probably because of sorption or precipitation effects after release from the glass matrix. After the initial few days, most elements …
Date: August 20, 1982
Creator: Buddemeier, R. W.; Coles, D. G.; Mensing, R. W.; Rego, J. & Weed, H. C.
Object Type: Report
System: The UNT Digital Library
Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite (open access)

Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite

An equation of state previously used by the author is developed further and applied to geologic media. The equation is of the same form as the Murnaghan equation of state, but with the elastic constant terms replaced by the cohesive energy density (internal pressure), and the exponential term given as a sum of the Gruneisen parameter and the gaseous adiabatic exponent. Data for shock compression of silica, basalt, and dolomite are analyzed according to the equation.
Date: December 20, 1965
Creator: Rogers, L.A.
Object Type: Article
System: The UNT Digital Library
Summary data for U. S. commercial nuclear power plants in the United States (open access)

Summary data for U. S. commercial nuclear power plants in the United States

A compilation of data is presented for all United States commercial nuclear power plants for which a construction permit application was made through the Nuclear Regulatory Commission. The data are compiled in four separate tables with cross-referencing indexes: Table 1--General Data; Table 2--Reactor Data; Table 3--Site Data, and Table 4--Circulating-Water System Data. The power plants are listed in numerical order by docket number in all four tables.
Date: March 20, 1978
Creator: Heddleson, F.A.
Object Type: Report
System: The UNT Digital Library
THE HEAT CAPACITY OF BERYLLIUM CARBIDE POWDER IN STAINLESS STEEL CAPSULES AS A FUNCTION OF TEMPERATURE (400-1800 F) (open access)

THE HEAT CAPACITY OF BERYLLIUM CARBIDE POWDER IN STAINLESS STEEL CAPSULES AS A FUNCTION OF TEMPERATURE (400-1800 F)

The mean heat capacity of a sample of powdered beryllium carbide, a possible moderator material for a nuclear reactor, was determined as a function of temperature. A thin-walled stainless steel capsule containing the material was heated in an electric furnace and dropped into a water calorimeter. The following linear equation for mean heat capacity over the temperature range 50 f C-T f C as a function of temperature, T, was derived from the data by the method of least squares: C/sub p/ = 0.299 + 2.16 x 10/sup -4/ T f C el temperatures 0.005 cal gm/sup -1/( f C)/sup -1/. The numerical value of C/sub p/ expressed by this equation is also equal to the mean heat capacity in Btu lb/sup -1/( f F)/sup -1/. (auth)
Date: April 20, 1949
Creator: Powers, H.; Kostigen, T. & Trice, J.B.
Object Type: Report
System: The UNT Digital Library
REPORT ON GLOVE BOXES AND CONTAINMENT ENCLOSURES (open access)

REPORT ON GLOVE BOXES AND CONTAINMENT ENCLOSURES

Criteria and guide lines are presented for the design, construction, and operation of safe, economical, and efficient glove boxes and associated facilities based upon present conditions and anticipated changes. Comprehensive discussion of glove box materials and components, safety and fire prevention methods, health physics problems, operational considerations, and brief descriptions of AEC installations are included. (39 references) (C.H.)
Date: June 20, 1962
Creator: Garden, N.B. ed.
Object Type: Report
System: The UNT Digital Library