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Probability based load criteria for the design of nuclear structures: a critical review of the state-of-the-art (open access)

Probability based load criteria for the design of nuclear structures: a critical review of the state-of-the-art

Structures for nuclear power plant facilities must be designed to withstand safely and effectively all kinds of loads and load combinations that may be expected to occur during their lifetime. The traditional methods of structural design attempt to account for the inevitable variability in the loads, material strengths, in-service environments, and fabrication process, etc., through the use of safety factor, allowable stresses or load and resistance factors. These approaches may result in an unknown and nonuniform reliability because of the subjective manner in which the safety factors have been determined. The stochastic nature loads and the uncertainties in material properties dictate a probabilistic approach for a rational assessment of structural safety and performance. This report presents: an in-depth review of the state-of-the-art pertaining to probability-based analysis and design of civil engineering structures; basis for extending existing probability-based methods to seismic category I nuclear structures; and the availability of the pertinent data required to perform probabilistic analysis for seismic category I nuclear structures.
Date: April 1, 1981
Creator: Shinozuka, M.; Ellingwood, B.R.; Wang, P.C.; Meyer, C.; Wen, Y.K.; Kao, S. et al.
Object Type: Report
System: The UNT Digital Library
Neutron-detection apparatus (open access)

Neutron-detection apparatus

An atomic fission counting apparatus used for neutron detection is provided with spirally curved electrode plates uniformly spaced apart in a circular array and coated with fissile material.
Date: April 24, 1981
Creator: Kopp, M.K. & Valentine, K.H.
Object Type: Patent
System: The UNT Digital Library
System for producing a uniform rubble bed for in-situ processes (open access)

System for producing a uniform rubble bed for in-situ processes

A method and a cutter are disclosed for producing a large cavity filled with a uniform bed of rubblized oil shale or other material, for in-situ processing. A raise drill head has a hollow body with a generally circular base and sloping upper surface. A hollow shaft extends from the hollow body. Cutter teeth are mounted on the upper surface of the body and relatively small holes are formed in the body between the cutter teeth. Relatively large peripheral flutes around the body allow material to drop below the drill head. A pilot hole is drilled into the oil shale deposit. The pilot hole is reamed into a large diameter hole by means of a large diameter raise drill head or cutter to produce a cavity filled with rubble. A flushing fluid, such as air, is circulated through the pilot hole during the reaming operation to remove fines through the raise drill, thereby removing sufficient material to create sufficient void space, and allowing the larger particles to fill the cavity and provide a uniform bed of rubblized oil shale.
Date: April 10, 1981
Creator: Galloway, Terry R.
Object Type: Patent
System: The UNT Digital Library
Method for producing nuclear fuel (open access)

Method for producing nuclear fuel

Nuclear fuel is made by contacting an aqueous solution containing an actinide salt with an aqueous solution containing ammonium hydroxide, ammonium oxalate, or oxalic acid in an amount that will react with a fraction of the actinide salt to form a precipitate consisting of the hydroxide or oxalate of the actinide. A slurry consisting of the precipitate and solution containing the unreacted actinide salt is formed into drops which are gelled, calcined, and pressed to form pellets.
Date: April 24, 1981
Creator: Haas, P.A.
Object Type: Patent
System: The UNT Digital Library
Analytical and experimental system studies of combined photovoltaic/thermal systems. Technical status report No. 12, February-March 1981 (open access)

Analytical and experimental system studies of combined photovoltaic/thermal systems. Technical status report No. 12, February-March 1981

Progress in the photovoltaic/thermal (PV/T) research program is indicated on a Milestone Chart, and a monthly history of the funds expended is graphed. Technical progress includes computer simulation of crude oil dewatering process, a simplified technique for predicting long term collector performance, PV/T concentrator collector testing, and participation in national standards development. Appended are a paper describing the collector performance calculation technique, a description of the PV/T concentrator, and a report for testing PV/T collectors. (LEW)
Date: 1981-04~
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Americium purification by a combined anion exchange and bidentate organophosphorus solvent extraction process. [Patent application] (open access)

Americium purification by a combined anion exchange and bidentate organophosphorus solvent extraction process. [Patent application]

Americium is separated from mixtures containing plutonium, other actinides, and other non-lanthamide impurities, by a combined process of anion exchange resin sorption to remove plutonium, and a bidentate organophosphorus solvent extraction of americium of the anion exchange resin effluent. Dihexyl-N,N-diethylcarbamylmethylenephosphonate is a preferred solvent. The initial mixture may be subjected to a cation exchange operation to remove monovalent impurities. The process is especially effective when aluminum, zinc, lead, and copper are present in significant quantities in the original mixture.
Date: April 10, 1981
Creator: Navratil, J.D. & Martella, L.L.
Object Type: Patent
System: The UNT Digital Library
Dust-Feed Mechanism (open access)

Dust-Feed Mechanism

The invention is a dust feed device for delivery of a uniform supply of dust for long periods of time to an aerosolizing means for production of a dust suspension. The device utilizes at least two tandem containers having spiral brushes within the containers which transport the dust from a supply to the aerosolizer means.
Date: April 6, 1981
Creator: Milliman, Edward M.
Object Type: Patent
System: The UNT Digital Library
Polarized negative ions (open access)

Polarized negative ions

This paper presents a survey of methods, commonly in use or under development, to produce beams of polarized negative ions for injection into accelerators. A short summary recalls how the hyperfine interaction is used to obtain nuclear polarization in beams of atoms. Atomic-beam sources for light ions are discussed. If the best presently known techniques are incorporated in all stages of the source, polarized H/sup -/ and D/sup -/ beams in excess of 10 ..mu..A can probably be achieved. Production of polarized ions from fast (keV) beams of polarized atoms is treated separately for atoms in the H(25) excited state (Lamb-Shift source) and atoms in the H(1S) ground state. The negative ion beam from Lamb-Shift sources has reached a plateau just above 1 ..mu..A, but this beam current is adequate for many applications and the somewhat lower beam current is compensated by other desirable characteristics. Sources using fast polarized ground state atoms are in a stage of intense development. The next sections summarize production of polarized heavy ions by the atomic beam method, which is well established, and by optical pumping, which has recently been demonstrated to yield very large nuclear polarization. A short discussion of proposed ion sources for …
Date: April 1, 1981
Creator: Haeberli, W.
Object Type: Article
System: The UNT Digital Library
Separator assembly for use in spent-nuclear-fuel shipping cask. [Patent application] (open access)

Separator assembly for use in spent-nuclear-fuel shipping cask. [Patent application]

A separator assembly for use in a spent-nuclear-fuel shipping cask has a honeycomb-type wall structure defining parallel cavities for holding nuclear fuel assemblies. Tubes formed of an effective neutron-absorbing material are embedded in the wall structure around each of the cavities and provide neutron flux traps when filled with water.
Date: April 24, 1981
Creator: Bucholz, J.A.
Object Type: Patent
System: The UNT Digital Library
In support of Heber Ethanol Fuel Facility, Imperial Valley, California. Quarterly report No. 1, December 1980-February 1981 (open access)

In support of Heber Ethanol Fuel Facility, Imperial Valley, California. Quarterly report No. 1, December 1980-February 1981

Progress is reported on the following tasks and issues: geothermal resource evaluation, process engineering, marketing, environmental concerns, and permit processing and legal issues. (MHR)
Date: April 1, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Fracture and hydrology data from field studies at Stripa, Sweden (open access)

Fracture and hydrology data from field studies at Stripa, Sweden

The purpose of this report is to present the basic fracture and hydrology data collected as part of the joint LBL-KBS fracture hydrology program at Stripa, Sweden. A detailed description of the fracture-core logging and hydrology borehole testing procedures is included as well as a description of how the fracture and hydrology data were coded and organized. Based on this coding a series of computer data files for the fracture and hydrology borehole data have been constructed and these are described in detail. The fracture data file for one borehole is presented as an example in an appendix along with all of the raw and some partially processed and analyzed fracture hydrology data files. A detailed description of how this data will be analyzed to develop a thorough understanding of the fracture system and hydrogeologic characteristics of the Stripa site is presented.
Date: April 1, 1981
Creator: Gale, J.E.
Object Type: Report
System: The UNT Digital Library
Thermoelectric Materials Evaluation Program. Annual technical report for fiscal years 1980/1981 (open access)

Thermoelectric Materials Evaluation Program. Annual technical report for fiscal years 1980/1981

During this contract period, all major contract milestones were accomplished. This included the fabrication and test of two N-legs, three single-couple assemblies, and three six-couple modules. The BOL performance objective was met and the degradation rate of 0.3%/1000 hours was nearly met for elements, couples, and modules. Considerable effort was spent in understanding the ratcheting phenomenon on the P-leg (cycle resistance changes at the hot end). A designed series of experiments was performed to identify the effect of contact pressure and hot junction temperature on P-leg degradation (time to onset of ratcheting, etc.). At the end of the fiscal year the results of this experimentation indicated that the theoretical estimate of an acceleration factor of twenty-one for module tests (915/150/sup 0/C, 14.0 amperes) is valid.
Date: April 1981
Creator: Hinderman, J.D.
Object Type: Report
System: The UNT Digital Library
Cermets and method for making same (open access)

Cermets and method for making same

The present invention is directed to a method for making a wide variety of general-purpose cermets and for radioactive waste disposal from ceramic powders prepared from urea-dispersed solutions containing various metal values. The powders are formed into a compact and subjected to a rapid temperature increase in a reducing atmosphere. During this reduction, one or more of the more readily reducible oxides in the compact is reduced to a selected substoichiometric state at a temperature below the eutectic phase for that particular oxide or oxides and then raised to a temperature greater than the eutectic temperature to provide a liquid phase in the compact prior to the reduction of the liquid phase forming oxide to solid metal. This liquid phase forms at a temperature below the melting temperature of the metal and bonds together the remaining particulates in the cermet to form a solid polycrystalline cermet.
Date: April 1, 1981
Creator: Aaron, W. S.; Kinser, D. L. & Quinby, T. C.
Object Type: Patent
System: The UNT Digital Library
Solar coal-gasification reactor with pyrolysis-gas recycle. [Patent application] (open access)

Solar coal-gasification reactor with pyrolysis-gas recycle. [Patent application]

Coal (or other carbonaceous matter, such as biomass) is converted into a product gas that is substantially free from hydrocarbons. The coal is fed into a solar reactor, and solar energy is directed into the reactor onto coal char, creating a gasification front and a pyrolysis front. A gasification zone is produced well above the coal level within the reactor. A pyrolysis zone is produced immediately above the coal level. Steam, injected into the reactor adjacent to the gasification zone, reacts with char to generate product gases. Solar energy supplies the energy for the endothermic steam-char reaction. The hot product gases flow from the gasification zone to the pyrolysis zone to generate hot char. Gases are withdrawn from the pyrolysis zone and reinjected into the region of the reactor adjacent the gasification zone. This eliminates hydrocarbons in the gas by steam reformation on the hot char. The product gas is withdrawn from a region of the reactor between the gasification zone and the pyrolysis zone. The product gas will be free of tar and other hydrocarbons, and thus be suitable for use in many processes.
Date: April 6, 1981
Creator: Aiman, W.R. & Gregg, D.W.
Object Type: Patent
System: The UNT Digital Library
Method of recovery of alkali-metal constituents from coal-conversion residues. [Patent application] (open access)

Method of recovery of alkali-metal constituents from coal-conversion residues. [Patent application]

A coal gasification operation or similar conversion process is carried out in the presence of an alkali metal-containing catalyst producing char particles containing alkali metal residues. Alkali metal constituents are recovered from the particles by burning the particles to increase their size and density and then leaching the particles of increased size and density with water, to extract the water-soluble alkali metal constituents.
Date: April 22, 1981
Creator: unknown
Object Type: Patent
System: The UNT Digital Library
Small scale hydroelectric power potential in Nevada: a preliminary reconnaissance survey (open access)

Small scale hydroelectric power potential in Nevada: a preliminary reconnaissance survey

This preliminary reconnaissance survey is intended to: develop a first estimate as to the potential number, location and characteristics of small-scale (50 kW to 15 MW) hydroelectric sites in Nevada; provide a compilation of various Federal and state laws and regulations, including tax and financing regulations, that affect small-scale hydroelectric development and provide information on sources of small-scale hydroelectric generation hardware and consultants/ contractors who do small scale hydroelectric work. The entire survey has been conducted in the office working with various available data bases. The site survey and site evaluation methods used are described, and data are tabulated on the flow, power potential, predicted capital expenditures required, etc. for 61 potential sites with measured flows and for 77 sites with derived flows. A map showing potential site locations is included. (LCL)
Date: April 1, 1981
Creator: Cochran, G.F.; Fordham, J.W.; Richard, K. & Loux, R.
Object Type: Report
System: The UNT Digital Library
Environmental assessment for Kelley Hot Spring geothermal project: Kelley Hot Spring Agricultural Center (open access)

Environmental assessment for Kelley Hot Spring geothermal project: Kelley Hot Spring Agricultural Center

The environmental impacts of an integrated swine production unit are analyzed together with necessary ancillary operations deriving its primary energy from a known geothermal reservoir in accordance with policies established by the National Energy Conservation Act. This environmental assessment covers 6 areas designated as potentially feasible project sites, using as the basic criteria for selection ground, surface and geothermal water supplies. The six areas, comprising +- 150 acres each, are within a 2 mile radius of Kelley Hot Springs, a known geothermal resource of many centuries standing, located 16 miles west of Alturas, the county seat of Modoc County, California. The project consists of the construction and operation of a 1360 sow confined pork production complex expandable to 5440 sows. The farrow to finish system for 1360 sows consists of 2 breeding barns, 2 gestation barns, 1 farrowing and 1 nursery barn, 3 growing and 3 finishing barns, a feed mill, a methane generator for waste disposal and water storage ponds. Supporting this are one geothermal well and 1 or 2 cold water wells, all occupying approximately 12 acres. Environmental reconnaissance involving geology, hydrology, soils, vegetation, fauna, air and water quality, socioeconomic, archaelogical and historical, and land use aspects were …
Date: April 1, 1981
Creator: Neilson, J.A.
Object Type: Report
System: The UNT Digital Library
RTNS-II targets: cooling channel collapse under simulated bonding conditions (open access)

RTNS-II targets: cooling channel collapse under simulated bonding conditions

We experimentally determined the pressure limits that can be used to autoclave-bond RTNS-II targets without crushing the internal cooling channels. The maximum pressures are 40 to 55 MPa (6 to 8 ksi) in the 300-to-450/sup 0/C temperature regime.
Date: April 2, 1981
Creator: Ludemann, W.D.; Brady, R.L. & Schumacher, B.J.
Object Type: Report
System: The UNT Digital Library
Transposable elements and genetic instabilities in crop plants (open access)

Transposable elements and genetic instabilities in crop plants

Transposable elements have long been associated with certain unstable loci in maize and have been intensively studied by McClintock and others. It is known that a transposable element can control the expression of the structural genes at the locus where it resides. These controlling elements in maize are now beginning to be studied at the molecular level. Using recombinant molecular probes we have been able to describe the changes induced by the controlling element Ds at the shrunken locus. Ds elements appear to be large and dissimilar insertions into the wild-type locus - two elements actually map within the transcribed region of the gene. Genetic instabilities have been described in other economically important plants but the bases for these phenomena have not been understood. We believe that it is likely that some of these instabilities are the result of transposable element activity much as in the case of maize.
Date: April 10, 1981
Creator: Burr, B. & Burr, F.
Object Type: Article
System: The UNT Digital Library
Raft River condenser-tube examination (open access)

Raft River condenser-tube examination

In the program of development of a water treatment for the 5 MW Raft River power plants' carbon steel heat rejection system, four carbon steel tubes were analyzed in this batch. The results of visual and scanning electron microscope examination of the tubes are presented. (MHR)
Date: April 3, 1981
Creator: Suciu, D. F.
Object Type: Report
System: The UNT Digital Library
New Jersey State Briefing Book for low-level radioactive waste management (open access)

New Jersey State Briefing Book for low-level radioactive waste management

The New Jersey state Briefing Book is one of a series of State briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in New Jersey. The profile is the result of a survey of NRC licensees in New Jersey. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may impact waste management practices in New Jersey.
Date: April 1, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
ac-resistance-measuring instrument (open access)

ac-resistance-measuring instrument

An auto-ranging ac resistance measuring instrument for remote measurement of the resistance of an electrical device or circuit connected to the instrument includes a signal generator which generates an ac excitation signal for application to a load, including the device and the transmission line, a monitoring circuit which provides a digitally encoded signal representing the voltage across the load, and a microprocessor which operates under program control to provide an auto-ranging function by which range resistance is connected in circuit with the load to limit the load voltage to an acceptable range for the instrument, and an auto-compensating function by which compensating capacitance is connected in shunt with the range resistance to compensate for the effects of line capacitance.
Date: April 22, 1981
Creator: Hof, P. J.
Object Type: Patent
System: The UNT Digital Library
Pennsylvania State Briefing Book for low-level radioactive waste management (open access)

Pennsylvania State Briefing Book for low-level radioactive waste management

The Pennsylvania State Briefing Book is one of a series of state briefing books on low-level radioactive waste management practices. It has been prepared to assist state and federal agency officials in planning for safe low-level radioactive waste disposal. The report contains a profile of low-level radioactive waste generators in Pennsylvania. The profile is the result of a survey of NRC licensees in Pennsylvania. The briefing book also contains a comprehensive assessment of low-level radioactive waste management issues and concerns as defined by all major interested parties including industry, government, the media, and interest groups. The assessment was developed through personal communications with representatives of interested parties, and through a review of media sources. Lastly, the briefing book provides demographic and socioeconomic data and a discussion of relevant government agencies and activities, all of which may impact waste management practices in Pennsylvania.
Date: April 1, 1981
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Nuclear reactor control apparatus. [FBR] (open access)

Nuclear reactor control apparatus. [FBR]

Nuclear reactor safety rod release apparatus comprises a ring which carries detents normally positioned in an annular recess in outer side of the rod, the ring being held against the lower end of a drive shaft by magnetic force exerted by a solenoid carried by the drive shaft. When the solenoid is de-energized, the detent-carrying ring drops until the detents contact a cam surface associated with the lower end of the drive shaft, at which point the detents are cammed out of the recess in the safety rod to release the rod from the drive shaft. In preferred embodiments of the invention, an additional latch is provided to release a lower portion of a safety rod under conditions that may interfere with movement of the entire rod.
Date: April 16, 1981
Creator: Sridhar, B.N.
Object Type: Patent
System: The UNT Digital Library