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An Analytical Study of the Feasibility of Irradiating U233/Th232 Metal Fuel Experiments in EBR-II

Description: Recent concerns about the proliferation and diversion of plutonium have lead to reconsideration of Uranium-233/Thorium-232 fuel cycles. Although thorium fuels have been studied earlier, much of that work is incomplete; consequently, additional irradiation studies will be necessary.
Date: 1979?
Creator: Foltman, A. J. & Meneghetti, D.
Partner: UNT Libraries Government Documents Department

Estimation of Particle Flux and Remineralization Rate from Radioactive Disequilibrium

Description: Reactive radionuclides, such as the thorium isotopes, show measurable deficiencies in the oceanic water column because of their removal by chemical scavenging due to the particle flux. Measurement of the deficiency, coupled with measurement of the radionuclide concentration in particles, allows a determination of the effective particle sinking velocity. Results to date suggest that the effective particle sinking velocity is remarkably invariant with depth. This leads to the tentative suggestion that POC concentration profiles may, to a good approximation, be used directly to determine length scales for the remineralization of sinking organic matter. Further measurements are in progress to test this idea and to evaluate its limitations. Knowledge of the remineralization length scale is essential to an evaluation of the efficiency of the biological pump as a means for deep sequestering of carbon in the ocean.
Date: May 24, 2004
Creator: Bacon, Michael P. & Francois, Roger
Partner: UNT Libraries Government Documents Department

Selection of Actinide Chemical Analogues for WIPP Tests: Potential Nonradioactive Sorbing and Nonsorbing Tracers for Study of Ion Transport in the Environment

Description: Chemical characteristics of the actinides (Th, U, Np, Pu, Am) have been studied relative to nonradioactive chemical elements that have similar characteristics in an attempt to identify a group of actinide chemical analogues that are nonradioactive. In general, the chemistries of the actinides, especially U, Np, Pu, and Am, are very complex and attempts to identify a single chemical analogue for each oxidation state were not successful. However, the rationale for selecting a group of chemical analogues that would mimic the actinides as a group is provided. The categorization of possible chemical analogues (tracers) with similar chemical properties was based on the following criteria. Categorization was studied according.
Date: August 1, 1998
Creator: Spall, Dale & Villarreal, Robert
Partner: UNT Libraries Government Documents Department

Final Report for the Light Water Breeder Reactor Proof-of-Breeding Analytical Support Project

Description: The technology of breeding uranium-233 from thorium-232 in a light water reactor is being developed and evaluated by the Westinghouse Bettis Atomic Power Laboratory (BAPL) through operation and examination of the Shippingport Light Water Breeder Reactor (LWBR). Bettis is determining the end-of-life (EOL) inventory of fissile uranium in the LWBR core by nondestructive assay of a statistical sample comprising approximately 500 EOL fuel rods. This determination is being made with an irradiated-fuel assay gauge based on neutron interrogation and detection of delayed neutrons from each rod. The EOL fissile inventory will be compared with the beginning-of-life fissile loading of the LWBR to determine the extent of breeding. In support of the BAPL proof-of-breeding (POB) effort, Argonne National Laboratory (ANL) carried out destructive physical, chemical, and radiometric analyses on 17 EOL LWBR fuel rods that were previously assayed with the nondestructive gauge. The ANL work included measurements on the intact rods; shearing of the rods into pre-designated contiguous segments; separate dissolution of each of the more than 150 segments; and analysis of the dissolver solutions to determine each segment's uranium content, uranium isotopic composition, and loading of selected fission products. This report describes the facilities in which this work was carried out, details operations involved in processing each rod, and presents a comprehensive discussion of uncertainties associated with each result of the ANL measurements.
Date: May 1987
Creator: Graczyk, D. G.; Hoh, J. C.; Martino, F. J.; Nelson, R. E.; Osudar, John & Levitz, Norman M.
Partner: UNT Libraries Government Documents Department

Potential radiological doses associated with the disposal of petroleum industry NORM via landspreading. Final report, September 1998

Description: As a result of oil and gas production and processing operations, naturally occurring radioactive materials (NORM) sometimes accumulate at elevated concentrations in by-product waste streams. The primary radionuclides of concern in NORM wastes are radium-226 of the uranium-238 decay series, and radium-228, of the thorium-232 decay series. The production waste streams most likely to be contaminated by elevated radium concentrations include produced water, scale, and sludge. Scales and sludges removed from production equipment often are disposed of by landspreading, a method in which wastes are spread over the soil surface to allow the hydrocarbon component of the wastes to degrade. In this study, the disposal of NORM-contaminated wastes by landspreading was modeled to evaluate potential radiological doses and resultant health risks to workers and the general public. A variety of future land use scenarios--including residential, industrial, recreational, and agricultural scenarios--were considered. The waste streams considered included scales and sludges containing NORM above background levels. The objectives of this study were to (1) estimate potential radiological doses to workers and the general public resulting from the disposal of NORM wastes by noncommercial landspreading activities and (2) analyze the effect of different land use scenarios on potential doses.
Date: December 1, 1998
Creator: Smith, K.P.; Blunt, D.L. & Arnish, J.J.
Partner: UNT Libraries Government Documents Department

Transformation rates and fate of dissolved, colloidal and particulate forms of organic carbon in ocean margins. Final report, May 1, 1992--April 3, 1995

Description: The goal of this proposal was to develop new sampling and analytical techniques which could be used to understand the transformation rates and mechanisms of exchange between dissolved, colloidal, small particle and large particle size classes of organic carbon in ocean margins. To meet this goal, the authors focused on the development of cross-flow filtration (CFF) for the isolation of colloidal material from the dissolved phase in seawater. In addition, they tested and optimized high sensitivity techniques for the measurement of thorium isotopes using thermal ionization mass spectrometry (TIMS) and carbon isotopes using accelerator mass spectrometry (AMS) and stable C mass spectrometric techniques. In this final report, they highlight some of these new sampling and analytical developments as well as preliminary results from the first DOE cruise this past April. The report is broken down into 4 sections, namely (1) colloidal sampling strategies, (2) TIMS analytical developments, (3) carbon isotopic measurements and (4) results from the R/V Columbus Iselin cruise. For more detailed discussion of the findings, they have included as an appendix to this final report manuscripts which have been published or will be submitted during this funding cycle.
Date: November 1, 1998
Creator: Buesseler, K.O.; Moran, S.B.; Bauer, J.E. & Druffel, E.R.M.
Partner: UNT Libraries Government Documents Department

Weldon Spring Site environmental report for calendar year 1997

Description: This report describes the environmental monitoring programs at the Weldon Spring Site Remedial Action Project (WSSRAP). The objectives of these programs are to assess actual or potential exposure to contaminant effluents from the project area by providing public use scenarios and dose estimates, to demonstrate compliance with Federal and State permitted levels and regulations, and to summarize trends and/or changes in contaminant concentrations identified through environmental monitoring. Comprehensive monitoring indicated that emissions of radiological compounds in airborne and surface water discharges from the Weldon Spring site consisted primarily of Rn-220 gas, isotopes of thorium and radium, and natural uranium. Airborne Rn-220 emissions were estimated to be 42 Ci (1.6E12 Bq), while emissions from a combination of thorium, radium, and natural uranium isotopes to air and surface water were estimated to be 0.018 Ci (6.7E8 Bq), for a total of 25,000 g (25 kg). There was no measurable impact to any drinking water source.
Date: August 1, 1998
Partner: UNT Libraries Government Documents Department

The Determination Thorium Isotopic Ratios by Radiochemical Methods

Description: >A sensitive analytical method was needed to determine the total thorium content and the Th/sup 2//sup 3//sup 0/ isotopic abundance in a number of uranium ore and mill talling samples available in the United States. A procedure was developed using absolute alpha counting to determine Th/sup 2//sup 3//sup 0/ and neutron activation analysis to determine Th/sup 2//sup 3//sup 2/. The method is highly specific with a sensitivity on the order of 10/sup -//sup 1//sup 0/ grams for either isotope and was found to give reliable data for the various sample types of interest. (auth)
Date: January 1, 1960
Creator: Matsumoto, W. Y.
Partner: UNT Libraries Government Documents Department

Thorium resonance ionization mass spectrometry for geochronological and geochemical applications

Description: Resonance Ionization Mass Spectrometry (RIMS) is being developed to measure thorium isotopics from geological samples. These measurements, in conjunction with uranium measurements by thermal ionization, permit geochronological dating in the timescale of 10,000 to 350,000 years. 15 refs., 2 figs.
Date: January 1, 1990
Creator: Fearey, Bryan L.; Johnson, Stephen G.; Nogar, Nicholas; Murrell, Michael T. & Miller, Charles M.
Partner: UNT Libraries Government Documents Department

The role of a detailed aqueous phase source release model in the LANL Area G performance assessment

Description: The Performance Assessment for the LANL Low-Level Radioactive Waste (LLRW) Disposal Facility, Area G, is on-going. A detailed review of the inventory data base records and the existing models for source release led to the development of a new modeling capability to describe the liquid phase aqueous transport from the waste package volumes. Inventory is sorted into four release form categories and screened in a comparison of leachate concentrations to the drinking water limit. Percolation through the disposal unit is prescribed in an independent surface water balance model incorporating site rainfall statistics. Waste package types and the disposal unit matrix have independently specified solubility limits and solid-liquid phase partition coefficients, or Kd values. Analytic solutions for inventory limited release of each nuclide in each of the four different waste package release forms are computed. Isotopic contributions are summed over elements to limit the waste package liquid phase concentrations to the elemental solubility limits. Time dependent releases from the waste packages for each nuclide which may be inventory or solubility limited are specified as model output which is provided as the source term to the unsaturated transport model. The waste package efflux is distributed over the 2-D unsaturated zone model grid points corresponding to the cross-sections for 5 representative disposal units within the mesa top. Results show the Area G release is dominated by the inventory in the rapid release waste form (Kd = 0), which percolates from the waste packages over 5--100 years and from the disposal unit over 50--1,000 years. Nuclides in waste package categories with larger Kd values are released proportionately slower. U and Th are the main nuclides of concern released as solubility limited nuclides from the historical inventory at Area G.
Date: April 1, 1996
Creator: Vold, E.L.; Hollis, D.; Longmire, P.; Springer, E.; Birdsell, K. & Shuman, R.
Partner: UNT Libraries Government Documents Department

Derivation of guidelines for uranium residual radioactive material in soil at the New Brunswick Site, Middlesex County, New Jersey

Description: Residual radioactive material guidelines for uranium in soil were derived for the New Brunswick Site, located in Middlesex County, New Jersey. This site has been designated for remedial action under the Formerly Utilized Sites Remedial Action Program of the US Department of Energy (DOE). Residual radioactive material guidelines for individual radionuclides of concern and total uranium were derived on the basis of the requirement that the 50-year committed effective dose equivalent to a hypothetical individual who lives or works in the immediate vicinity of the New Brunswick Site should not exceed a dose of 30 mrem/yr following remedial action for the current-use and likely future-use scenarios or a dose of 100 mrem/yr for less likely future-use scenarios. The DOE residual radioactive material guideline computer code, RESRAD, was used in this evaluation; RESRAD implements the methodology described in the DOE manual for establishing residual radioactive material guidelines. The guidelines derived in this report are intended to apply to the remediation of these remaining residual radioactive materials at the site. The primary radionuclides of concern in these remaining materials are expected to be radium-226 and, to a lesser extent, natural uranium and thorium. The DOE has established generic cleanup guidelines for radium and thorium in soil; however, cleanup guidelines for other radionuclides must be derived on a site-specific basis.
Date: February 1, 1996
Creator: Dunning, D.; Kamboj, S.; Nimmagadda, M. & Yu, C.
Partner: UNT Libraries Government Documents Department

Characteristics of the samples in the FNG fission deposit collection

Description: Information concerning the samples in the Fast Neutron Generator (FNG) Group's fission deposit collection has been assembled. This includes the physical dimensions, isotopic analyses, half-lives, alpha emission rates specific activities and deposit weights. 10 refs., 9 figs., 5 tabs.
Date: December 1, 1990
Creator: Meadows, J.W.
Partner: UNT Libraries Government Documents Department

230Th-234U Age-Dating Uranium by Mass Spectrometry

Description: This is the standard operating procedure used by the Isotope Ratio Mass Spectrometry Group of the Chemical Sciences Division at LLNL for the preparation of a sample of uranium oxide or uranium metal for {sup 230}Th-{sup 234}U age-dating. The method described here includes the dissolution of a sample of uranium oxide or uranium metal, preparation of a secondary dilution, spiking of separate aliquots for uranium and thorium isotope dilution measurements, and purification of uranium and thorium aliquots for mass spectrometry. This SOP may be applied to uranium samples of unknown purity as in a nuclear forensic investigation, and also to well-characterized samples such as, for example, U{sub 3}O{sub 8} and U-metal certified reference materials. The sample of uranium is transferred to a quartz or PFA vial, concentrated nitric acid is added and the sample is heated on a hotplate at approximately 100 C for several hours until it dissolves. The sample solution is diluted with water to make the solution approximately 4 M HNO{sub 3} and hydrofluoric acid is added to make it 0.05 M HF. A secondary dilution of the primary uranium solution is prepared. Separate aliquots for uranium and thorium isotope dilution measurements are taken and spiked with {sup 233}U and {sup 229}Th, respectively. The spiked aliquot for uranium isotope dilution analysis is purified using EiChrom UTEVA resin. The spiked aliquot for thorium isotope dilution analysis is purified by, first, a 1.8 mL AG1x8 resin bed in 9 M HCl on which U adsorbs and Th passes through; second, adsorbing Th on a 1 mL AG1x8 resin bed in 8 M HNO{sub 3} and then eluting it with 9 M HCl followed by 0.1 M HCl + 0.005 M HF; and third, by passing the Th through a final 1.0 mL AG1x8 resin bed in 9 M HCl. ...
Date: April 18, 2012
Creator: Williams, R W & Gaffney, A M
Partner: UNT Libraries Government Documents Department

Evaluation and compilation of fission product yields 1993

Description: This document is the latest in a series of compilations of fission yield data. Fission yield measurements reported in the open literature and calculated charge distributions have been used to produce a recommended set of yields for the fission products. The original data with reference sources, and the recommended yields axe presented in tabular form. These include many nuclides which fission by neutrons at several energies. These energies include thermal energies (T), fission spectrum energies (F), 14 meV High Energy (H or HE), and spontaneous fission (S), in six sets of ten each. Set A includes U235T, U235F, U235HE, U238F, U238HE, Pu239T, Pu239F, Pu241T, U233T, Th232F. Set B includes U233F, U233HE, U236F, Pu239H, Pu240F, Pu241F, Pu242F, Th232H, Np237F, Cf252S. Set C includes U234F, U237F, Pu240H, U234HE, U236HE, Pu238F, Am241F, Am243F, Np238F, Cm242F. Set D includes Th227T, Th229T, Pa231F, Am241T, Am241H, Am242MT, Cm245T, Cf249T, Cf251T, Es254T. Set E includes Cf250S, Cm244S, Cm248S, Es253S, Fm254S, Fm255T, Fm256S, Np237H, U232T, U238S. Set F includes Cm243T, Cm246S, Cm243F, Cm244F, Cm246F, Cm248F, Pu242H, Np237T, Pu240T, and Pu242T to complete fission product yield evaluations for 60 fissioning systems in all. This report also serves as the primary documentation for the second evaluation of yields in ENDF/B-VI released in 1993.
Date: December 31, 1995
Creator: England, T. R. & Rider, B. F.
Partner: UNT Libraries Government Documents Department

Annual dose rate calculations for thermoluminescence dating

Description: Tabulations of decay data and dose rate calculations that are necessary for TL dating are presented. An effort has been made to collect the latest evaluated data and to catalog them in a form that is easily accessible, so that they may be updated as new revised values are reported. It is suggested that the largest error in thermoluminescence dating will come from sources other than the tabulated particle energies and branching ratios. These include: (a) the alpha to beta thermoluminescence efficiency determination; (b) concentration measurements of K, Rb, Th, and U; (c) all departures from secular equilibrium in the uranium and thorium decay chains; and (d) the imprecise calibration of laboratory radiation sources.
Date: January 1, 1978
Creator: Carriveau, G W & Troka, W
Partner: UNT Libraries Government Documents Department

Nuclear data review and compilation for ATW systems

Description: In order to solve the problem of nuclear power waste transmutation in neutron flux it is necessary to know the characteristics of neutron interaction for a great number of nuclei in the energy range from 0 to hundreds of MeV. The authors distinguished the most important aspect of this problem that one of nuclear data for actinides, (from Th to Cm isotopes) They have given the overview of evaluations of characteristic of interaction between neutrons and these nuclei leading to transformation from target-nucleus to neighboring actinide-nucleus or fission fragments in the limited energy range from 0 to 14 MeV. The review was carried out by comparison of mentioned characteristics from the modern versions of ENDL-82, JENDL-3, ENDF/B-6 and BROND-2 neutron evaluated data among themselves and with recommended data of previous publications and, in some cases, with the measurement results. ENDL-82 and ENDF/B-6 versions were made in USA laboratories, JENDL-3 was made in the laboratories of Japan and BROND-2 version was made in the laboratories of former USSR. The comparison of nuclear data from various libraries was carried out by the most economic method permitting, nevertheless, fully judge of available uncertainties in the knowledge of competitive nuclear data which are important from the point of view of problem of transmutation in various energies neutron flux. The following characteristics were considered: (a) fission and capture cross-sections at thermal point (E{sub n}=0.0253 eV); (b) infinitely dilute resonance integrals of fission and capture designated by I{sub f} and I{sub {gamma}} (c) averaged on {sup 252}Cf spontaneous fission neutron spectrum cross-sections of fission, capture and the (n,2n) reactions; (d) cross-sections of fission and the (n,2n), (n,3n) reactions at the point En = 14 MeV; (e) fission and capture resonance integrals for a interval of sets with the increasing upper (E {sub max}) and lower (E ...
Date: October 1, 1994
Creator: Guzhovskii, B.; Gorelov, V.; Il`in, V.; Farafontov, G. & Grebennikov, A.
Partner: UNT Libraries Government Documents Department

Minutes of Technical Division Steering Committee Meeting, September 13, 1955 -- Savannah River Laboratory

Description: The Steering Committee approved 8 studies related to separation processes, analytical chemistry, waste handling, and recycle development. Safety and security issues were discussed. Appendices detail the financial status of the Technical Division and estimated man months for development studies approved for the Purex Process, tritium separations, thorium recycle, U-235 separations, and 100-, 200-, and 300-Area studies in analytical chemistry development. The status of 25 other Technical Division studies are listed along with their budget.
Date: September 16, 1955
Creator: Evans, L. C.
Partner: UNT Libraries Government Documents Department

Determination of radionuclides in air

Description: The air in certain work areas at the Oak Ridge Gaseous Diffusion Plant is monitored for selected radionuclides to assure safety from toxic effects to personnel in the area. Some of the radionuclides that are determined are shown with their Radiation Protection Standard (RPS) values by means of a table. The RPS is the maximum average airborne contamination to which personnel may be exposed for one week without respiratory protection and is expressed as disintegrations per minute (dpm) per cubic meter (m/sup 3/) of air. It is desirable to make reliable measurements at a level which is 10% of the RPS to ensure that the detection limits are well below the RPS. Thorium, neptunium, plutonium, and uranium all have alpha emitting isotopes and it is their alpha activity which is measured. Results are tabulated.
Date: September 20, 1978
Creator: Rucker, Thomas L.
Partner: UNT Libraries Government Documents Department