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Nondestructive evaluation of LWR spent fuel shipping casks (open access)

Nondestructive evaluation of LWR spent fuel shipping casks

An analysis of nondestructive testing (NDT) methods currently being used to evaluate the integrity of Light Water Reactor (LWR) spent fuel shipping casks is presented. An assessment of anticipated NDT needs related to breeder reactor cask requirements is included. Specific R and D approaches to probable NDT problem areas such as the evaluation of austenitic stainless steel weldments are outlined.
Date: February 1, 1978
Creator: Ballard, D. W.
System: The UNT Digital Library
Presence of UV-endonuclease sensitive sites in daughter DNA of UV-irradiated mammalian cells. [3H-thymidine tracer] (open access)

Presence of UV-endonuclease sensitive sites in daughter DNA of UV-irradiated mammalian cells. [3H-thymidine tracer]

Asynchronous Chinese hamster cells were irradiated with 10 Jm/sup -2/ uv radiation and 0.25 to 4 hours later pulse-labeled with (/sup 3/H)thymidine. Cells synchronized by shaking off mitotic and G/sub 1/ cells were irradiated in either the G/sub 1/-phase or S-phase of the cell cycle and pulse-labeled with (/sup 3/H)thymidine in the S-phase. After a 12 to 14 hour chase in unlabeled medium, the DNA was extracted, incubated with Micrococcus luteus uv-endonuclease and sedimented in alkaline sucrose. The number of endonuclease sensitive sites decreased as the time between uv irradiation and pulse-labeling of daughter DNA increased. Further, there were significantly less endonuclease sensitive sites in the daughter DNA from cells irradiated in the G/sub 1/-phase than in the S-phase. These data indicate that very few, if any, dimers are transferred from parental DNA to daughter DNA and that the dimers detected in daughter DNA may be due to the irradiation of replicating daughter DNA before labeling.
Date: February 1, 1978
Creator: D'Ambrosio, S. & Setlow, R.B.
System: The UNT Digital Library
Preconcentration of plutonium radionuclides from natural waters. [Pu in Eniwetok ground water, lagoon and open ocean waters] (open access)

Preconcentration of plutonium radionuclides from natural waters. [Pu in Eniwetok ground water, lagoon and open ocean waters]

A large volume water sampler using manganese dioxide impregnated cartridges for the in situ separation of plutonium in sea water and ground water was studied. Plutonium concentrations obtained by this technique are compared with a radiochemical coprecipitation method. Consistent results were obtained between the two methods for water samples from the Pacific Ocean and Enewetak lagoon. Different results were noted from samples collected in the Enewetak reef and ground water stations. Using this preconcentration technique and the coprecipitation method it was shown that the physical-chemical characteristics of Pu in Enewetak reef and ground water are different from the lagoon and open ocean.
Date: February 1, 1978
Creator: Wong, K. M.; Nioshkin, V. E. & Jokela, T. A.
System: The UNT Digital Library
Prediction of electron beam welding spiking tendency (open access)

Prediction of electron beam welding spiking tendency

On the basis of measured temperature distributions in electron beam welding cavities it is shown that the vapor pressure force dominates in the lower region and the surface tension in the upper region. The region where these two forces are approximately equal is unstable and the surface tension force causes inward flow of liquid metal which tends to form a projection. For a specific material this projection location was found to depend on cavity depth. By postulating that the formation of liquid metal projections at this location results in cavity instabilities, a physical model for predicting when spiking would occur was purposed. A procedure then developed for determining the spiking tendency for a specified material and set of weld parameters is described.
Date: February 1, 1978
Creator: Schauer, D. A. & Geidt, W. H.
System: The UNT Digital Library
Energy-averaged neutron cross sections of fast-reactor structural materials (open access)

Energy-averaged neutron cross sections of fast-reactor structural materials

The status of energy-averaged cross sections of fast-reactor structural materials is outlined with emphasis on U.S. data programs in the neutron-energy range 1-10 MeV. Areas of outstanding accomplishment and significant uncertainty are noted with recommendations for future efforts. Attention is primarily given to the main constituents of stainless steel (e.g., Fe, Ni, and Cr) and, secondarily, to alternate structural materials (e.g., V, Ti, Nb, Mo, Zr). Generally, the mass regions of interest are A approximately 50 to 60 and A approximately 90 to 100. Neutron total and elastic-scattering cross sections are discussed with the implication on the non-elastic-cross sections. Cross sections governing discrete-inelastic-neutron-energy transfers are examined in detail. Cross sections for the reactions (n;p), (n;n',p), (n;..cap alpha..), (n;n',..cap alpha..) and (n;2n') are reviewed in the context of fast-reactor performance and/or diagnostics. The primary orientation of the discussion is experimental with some additional attention to the applications of theory, the problems of evaluation and the data sensitivity of representative fast-reactor systems.
Date: February 1, 1978
Creator: Smith, A.; McKnight, R. & Smith, D.
System: The UNT Digital Library
Review of issues relevant to acceptable risk criteria for nuclear waste management (open access)

Review of issues relevant to acceptable risk criteria for nuclear waste management

Development of acceptable risk criteria for nuclear waste management requires the translation of publicly determined goals and objectives into definitive issues which, in turn, require resolution. Since these issues are largely of a subjective nature, they cannot be resolved by technological methods. Development of acceptable risk criteria might best be accomplished by application of a systematic methodology for the optimal implementation of subjective values. Multi-attribute decision analysis is well suited for this purpose.
Date: February 22, 1978
Creator: Cohen, J.J.
System: The UNT Digital Library
Diffusion welding multifilament superconductive composites (open access)

Diffusion welding multifilament superconductive composites

Diffusion welding is shown to be a feasible method for joining composites of niobium-titanium superconductor alloy filaments in a pure copper matrix. Good results were repeatedly obtained using 15/sup 0/ scarf joints welded with externally heated tooling and simple uniaxial compression loading in a conventional hydraulic press. Weld cycles of less than one hour total elapsed time were readily attainable. Through proper closed-die design, it was possible to increase welding pressure sufficiently to use relatively low temperatures to coincide with the optimum aging heat treatment of the superconductor alloy. This temperature limitation is important to retain optimal superconductor properties. Confirming measurements of critical current density of welded joints at 4.2/sup 0/K are in progress. In the welded joints made under optimum conditions, there is bonding of all constituents, including superconductor filaments. Weld tooling which effectively contains the relatively fluid matrix, and resists deformation during repeated weld cycles, is essential to the successful application of the diffusion welding process to these composites.
Date: February 27, 1978
Creator: Witherell, C.E.
System: The UNT Digital Library
Purex process operation and performance: 1970 thoria campaign (open access)

Purex process operation and performance: 1970 thoria campaign

The Hanford Purex Plant has demonstrated suitability for reprocessing irradiated thoria (ThO/sub 2/) target elements on a campaign basis. A 1965 process test and major production campaigns conducted in 1966 and 1970 recovered nitrate solution form products totaling approximately 565 tons of thorium and 820 kilograms of /sup 233/U. The overall recoveries for the 1970 campaign based on reactor input data were 94.9 percent for thorium and 95.2 percent for uranium. The primary function of the Hanford Purex Plant is reprocessing of irradiated uranium fuel elements to separate and purify uranium, plutonium and neptunium. Converting the plant to thoria reprocessing required major process development work and equipment modifications. The operation and performance of the Plant during the 1970 thoria reprocessing campaign is discussed in this report. The discussion includes background information on the process and equipment, problems encountered, and changes recommended for future campaigns.
Date: February 1, 1978
Creator: Walser, R.L.
System: The UNT Digital Library
Technical aspects of coal-oil mixture combustion (open access)

Technical aspects of coal-oil mixture combustion

Coal-oil mixture (COM) combustion technology is regarded by the Department of energy as near term, and potentially applicable to existing utility and industrial steam generators, and for injection into blast furnaces. From work done previously, it has been established that COM can be existing boilers and blast furnaces. Therefore, the issues being addressed by the current DOE program are: (1) determination of best available technology to achieve environmentally-acceptable long-term reliable operation, and (2) determination of applications for which COM can be utilized economically. Some of the technological options have begun to be determined by projects already under way. However, many projects are still in the early stages of development.
Date: February 1, 1978
Creator: Freedman, S. I.; Foster, C. B. & Jamgochian, E. M.
System: The UNT Digital Library
Hydrogen production using fusion energy and thermochemical cycles. [Fe/sub 3/O/sub 4/-FeO, CrCl/sub 3/-CrCl/sub 2/, and UCl/sub 4/-UCl/sub 3/] (open access)

Hydrogen production using fusion energy and thermochemical cycles. [Fe/sub 3/O/sub 4/-FeO, CrCl/sub 3/-CrCl/sub 2/, and UCl/sub 4/-UCl/sub 3/]

Thermochemical cycles for the production of synthetic fuels would be especially suited for operation in conjunction with controlled thermonuclear fusion reactors because of the very high temperature energy which such reactors could supply. Furthermore, fusion energy when developed is considered to be an inexhaustable supply of energy. Several high-temperature two-step thermochemical cycles for the production of hydrogen are examined. A thermodynamic analysis of the Fe/sub 3/O/sub 4/--FeO, CrCl/sub 3/--CrCl/sub 2/, and UCl/sub 4/--UCl/sub 3/ pairs reveals the feasibility of the process. A more detailed process analysis is given for the Fe/sub 3/O/sub 4/--FeO system using steam as the heat transfer medium for decomposing the higher valent metal oxide for oxygen production, and hydrolysing the lower oxide for hydrogen production. The steam could be heated to high temperatures by refractory materials absorbing the 14-MeV neutrons in the blanket region of a fusion reactor. Process heat transfer and recovery could be accomplished by regenerative reactors. Proposed operating conditions, the energy balance and the efficiency of the water decomposition process are presented. With a fusion blanket temperature of 2500/sup 0/K, thermal efficiencies for hydrogen production of 74.4% may be obtained.
Date: February 1, 1978
Creator: Steinberg, M. & Dang, V.D.
System: The UNT Digital Library
Gamma spectrometric methods for measuring plutonium (open access)

Gamma spectrometric methods for measuring plutonium

Nondestructive analyses of plutonium can be made by detecting and measuring the gamma rays emitted by a sample. Although qualitative and semiquantitative assays can be performed with relative ease, only recently have methods been developed, using computer analysis techniques, that provide quantitative results. This paper reviews some new techniques developed for measuring plutonium. The features of plutonium gamma-ray spectra are reviewed and some of the computer methods used for spectrum analysis are discussed. The discussion includes a description of a powerful computer method of unfolding complex peak multiplets that uses the standard linear least-squares techniques of data analysis. This computer method is based on the generation of response profiles for the isotopes composing a plutonium sample and requires a description of the peak positions, relative intensities, and line shapes. The principles that plutonium isotopic measurements are based on are also developed, followed by illustrations of the measurement procedures as applied to the quantitative analysis of plutonium liquid and solid samples.
Date: February 16, 1978
Creator: Gunnink, R.
System: The UNT Digital Library
De minimis levels of radioactivity in waste management (open access)

De minimis levels of radioactivity in waste management

The authors define and discuss several approaches to establishing de minimis levels, with examples. In order to avoid creating still another constraint on waste facilities or controls, they suggest the term de minimis be applied only when based on environmental radioactivity, dose, or health effect. They further suggest that such usage implies case-by-case numerical evaluation for application to release rates or effluent concentrations.
Date: February 1, 1978
Creator: Corley, J.P. & Schiager, K.J.
System: The UNT Digital Library
Development of nickel-free austenitic stainless steels for ambient and cryogenic applications (open access)

Development of nickel-free austenitic stainless steels for ambient and cryogenic applications

A series of alloys have been developed as possible replacements for some austenitic stainless steels. These alloys utilized a Mn substitution for Ni and a reduced Cr concentration from the 18% ordinarily found in the AISI 300 series stainless steels to a concentration of 13%. The base system studied was an alloy containing Fe-16%Mn-13%Cr while other elements added included small additions of N, Si and Mo. A range of microstructures was produced from the alloying additions. The base composition had a triplex (fcc, hcp, bcc) structure while the most highly modified compositions were fully austenitic. Mechanical testing included tensile testing and Charpy V-notch testing conducted at various temperatures between -196/sup 0/C to 23/sup 0/C. Excellent combinations of strength and ductility were obtained (40--65 ksi yield strength, 100--125 ksi ultimate strength, 45--75% elongation and 60--80% reduction of area) at room temperature. Upper shelf energies in Charpy V-notch testing were as high as 185 ft-lbs with a ductile-brittle transition temperature (DBTT) of -160/sup 0/C. Analysis of fracture surfaces determined that alloys without interstitials had no transition in the mode of failure between room temperature and liquid nitrogen temperature. Results of an ASTM sensitization corrosion test, where the experimental alloys were compared to …
Date: February 1, 1978
Creator: Haddick, G. T.; Thompson, L. D.; Parker, E. R. & Zackay, V. F.
System: The UNT Digital Library
Precision etching of thick-film circuits of aluminum and aluminum-0. 1 wt% copper (open access)

Precision etching of thick-film circuits of aluminum and aluminum-0. 1 wt% copper

In certain high-current applications the resistance of the aluminum conductors is an important design parameter. Such a case is the aluminum exploding-bridge used in some nuclear detonators. The resistance of the network must be accurately known so that the individual bridge will receive the proper firing current. Vapor-deposited, thick aluminum films (0.011 mm) are often used to produce the necessary circuitry. These films are suitably masked and etched to make the conductors. Conventional etching methods for aluminum or aluminum-0.1 wt percent copper do not yield conductors with a well-defined, reproducible cross section. This results in unacceptable variations in electrical resistance. For this application, we have developed a new etching solution that contains 25 to 50 vol percent polyphosphoric acid, 75 to 50 vol percent orthophosphoric acid, and 10 to 30 g/l ferric chloride. Etching may be done at 55 to 65/sup 0/C, but for precision etching the temperature should be controlled to +-1/sup 0/C. The solution is useful for dip etching of aluminum circuits. The paper describes some limited production experience with this etch.
Date: February 15, 1978
Creator: Wiesner, H.J.
System: The UNT Digital Library
Proceedings of the heavy ion fusion workshop held at Brookhaven National Laboratory, Upton, New York, 17 October 1977 (open access)

Proceedings of the heavy ion fusion workshop held at Brookhaven National Laboratory, Upton, New York, 17 October 1977

Separate abstracts were prepared for each of the 50 included papers. (MOW)
Date: February 1, 1978
Creator: Smith, L. W.
System: The UNT Digital Library
Electrochemical studies of MHD channel electrode materials in molten potassium salt and coal slags (open access)

Electrochemical studies of MHD channel electrode materials in molten potassium salt and coal slags

Laboratory tests were conducted on some potential MHD elecrode materials to evaluate their electrochemical reactions. Electrode materials 0.25Fe/sub 3/O/sub 4/ 0.75MgAl/sub 3/O/sub 4/ (FMAS), La/sub 0/ /sub 95/Mg/sub 0/ /sub 03/CrO/sub 3/ (LMC), and 0.10Tb/sub 4/O/sub 7/ 0.90HfO/sub 2/ (THF) were tested in both liquid ana vapor K/sub 2/CO/sub 2/ and K/sub 2/SO/sub 4/, as well as potassium seed. Tests have confirmed that electrochemical reactions are substantially accelerated in these materials when used as electrical conductors. Electrochemical effects are functions of electrolyte composition (especially Fe and K), temperature, and electric current density.
Date: February 1, 1978
Creator: Marchant, D. D.; Griffin, C. W. & Bates, J. L.
System: The UNT Digital Library
Noncontact material testing using laser energy deposition and interferometry (open access)

Noncontact material testing using laser energy deposition and interferometry

A technique is described for the noncontact testing of materials using laser deposition to generate a stress pulse and interferometry to record the transient surface displacement. The dilatational wave speed can be measured and, in the particular case of rod or plate specimens, sufficient information can be obtained to evaluate the two elastic constants of an isotropic material. Several applications illustrating the advantages of the approach are summarized.
Date: February 6, 1978
Creator: Calder, C.A. & Wilcox, W.W.
System: The UNT Digital Library
CTR electrical insulators (open access)

CTR electrical insulators

Separate abstracts have been entered into the data base for each included paper. (MOW)
Date: February 1, 1978
Creator: unknown
System: The UNT Digital Library
Second topical conference on high-temperature plasma diagnostics (open access)

Second topical conference on high-temperature plasma diagnostics

This report contains the program and abstracts of papers presented at the Second American Physical Society Topical Conference on High Temperature Plasma Diagnostics, March 1-3, 1978, Santa Fe, New Mexico.
Date: February 1, 1978
Creator: Jahoda, F.C. & Freese, K.B. (comps.)
System: The UNT Digital Library
Transport equation theory of electron backscattering and x-ray production. [30 keV] (open access)

Transport equation theory of electron backscattering and x-ray production. [30 keV]

A transport equation theory of electron backscattering and x ray production is derived and applied to energy dissipation of 30-KeV electrons for copper as a function of depth and to the energy distribution of backscattered electrons for copper, aluminum, and gold. These results are plotted and compared with experiment. Plots for variations of backscattering with atomic number and with angle of incidence, and polar plots of backscattering for 30-keV electrons at normal incidence are also presented. 10 references, seven figures. (JFP)
Date: February 1, 1978
Creator: Fathers, D.J. & Rez, P.
System: The UNT Digital Library
Pulsed ferrite core tests for 50-ns linear induction accelerator (open access)

Pulsed ferrite core tests for 50-ns linear induction accelerator

The Lawrence Livermore Laboratory undertook an investigation of the properties of ferrite materials to be used in a 5-MeV, 50-ns linear induction accelerator. The investigation, on a part-time basis, lasted about one year and had the cooperation and helpful suggestions of several manufacturers: TDK of Japan, Phillips of Holland, and Stackpole of the U.S.A. Ferrites have been widely used as tuning cavities for proton synchrotron accelerators at radio frequencies. In such an application, the ..mu..Qf factor is used in describing the figure of merit for ferrites where a high duty factor requires low loss ferrites. In a linear induction accelerator with an average reprate of 5-Hz, the ferrite losses are negligible and the concept of complex permeability in describing the losses will not be introduced, but a large signal ..delta..B/..delta..H will be used to describe their properties. The properties of interest in designing the accelerating cavity were (1) flux swing ..delta..B = B/sub r/ + B/sub m/ greater than 0.5T; (2) a residual flux density B/sub r/ greater than or = to 0.15T with a reset no greater than 2 Oer; (3) a relatively high incremental ..mu.. greater than 400 to keep the excitation current small in relation to the …
Date: February 28, 1978
Creator: Reginato, L.; Cook, E.; Dexter, W. & Schmidt, J.
System: The UNT Digital Library
Vent clearing during a simulated loss-of-coolant accident in Mark I boiling-water-reactor pressure-suppression system (open access)

Vent clearing during a simulated loss-of-coolant accident in Mark I boiling-water-reactor pressure-suppression system

The response of the pressure-suspension containment system of Mark I boiling-water reactors to a loss-of-coolant accident (LOCA) is being studied. This response is a design basis for light-water nuclear reactors. Part of the study is being carried out on a /sup 1///sub 5/-scale experimental facility that models the pressure-suppression containment system of the Peach Bottom 2 nuclear power plant. The test series reported here focused on the initial or air-clearing phase of a hypothetical LOCA. Measured forces, measured pressures, and the hydrodynamic phenomena (observed with high-speed cameras) show a logical interrelationship.
Date: February 14, 1978
Creator: Pitts, J.H. & McCauley, E.W.
System: The UNT Digital Library
Recent work on sodium-cooled reactor purification systems (open access)

Recent work on sodium-cooled reactor purification systems

Fast Flux Test Facility (FFTF) cold traps, including the Reactor Primary Cold Trap, the Reactor Secondary Cold Trap and the Closed Loop Cold Trap were fabricated and their thermal performances measured on sodium test systems. The cold traps all met reactor requirements after necessary economizer modifications. Mercury tests were performed to study the effect of woven wire packing on the flow of a liquid metal adjacent to a heated vertical wall as occurs in the cold trap crystallizer. The mesh was observed to alter the velocity distribution in the natural convection flow region. Cold trapping experiments have been done to determine the interaction of hydrogen and tritium isotopes during precipitation. It was determined that the hydrogen removal rate is of primary importance in tritium removal from sodium. Isotopic exchange plays a negligible role in cold trapping tritium. A one-dimensional computer model has been developed to predict hydride and oxide precipitation patterns. Experiments have been done using an essentially one-dimensional (long, thin) tube to compare results with the model.
Date: February 1, 1978
Creator: Bloom, G.R. & McPheeters, C.C.
System: The UNT Digital Library
Energy-related environmental computer graphics systems in the Department of Energy Laboratories (open access)

Energy-related environmental computer graphics systems in the Department of Energy Laboratories

Computerized graphics techniques available in the Department of Energy's national laboratories for use in the environmental aspects of energy such as land use planning (including siting), and regional studies, environmental impact assessment are discussed. Areas covered include: computer graphics; mapping/cartography; image processing; animation; computer movies; satellite graphics; surface representation; land use analysis; pattern recognition; demographics analysis; ecological analysis; and biomedical applications. Descriptions of each graphics system included should be sufficient for a potential user to determine its possible use to him. Further, information is available by writing or telephoning the indicated contact person.
Date: February 1, 1978
Creator: unknown
System: The UNT Digital Library