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Photon burst mass spectrometry--ultrasensitive detection of rare isotopes

Description: Progress is reported on the development of a new technique for measurement of trace levels of radioisotopes which is based on fluorescence detection of output from a mass spectrometer. Significant achievements include the observation of fluorescence and burst signals from Kr isotopes, including enriched samples of {sup 85}Kr with a 4-collector system. An abundance sensitivity is demonstrated with {sup 83}Kr and {sup 85}Kr.
Date: February 1, 1995
Creator: Hansen, C.S.; Pan, X.J.; Fairbank, W.M. Jr.; Oona, H.; Chamberlin, E.P.; Nogar, N.S. et al.
Partner: UNT Libraries Government Documents Department

Photon burst mass spectrometry for the measurement of {sup 85}Kr at ambient levels

Description: Photon Burst Mass Spectrometry has been used to measure {sup 85}Kr in a sample with an abundance of 6 x 10{sup {minus}9}. Improvements in detection efficiency by the use of avalanche photodiodes cooled to liquid nitrogen temperature are reported, which should make possible measurement of {sup 85}Kr at the ambient atmospheric abundance of 10{sup {minus}11}. Potential applications include nuclear monitoring, atmospheric transport, and dating young ground water up to 40 years.
Date: December 1, 1998
Creator: Fairbank, W.M. Jr.; LaBelle, R.D. & Hansen, C.S.
Partner: UNT Libraries Government Documents Department

TREATMENT OF GASEOUS EFFLUENTS ISSUED FROM RECYCLING – A REVIEW OF THE CURRENT PRACTICES AND PROSPECTIVE IMPROVEMENTS

Description: The objectives of gaseous waste management for the recycling of nuclear used fuel is to reduce by best practical means (ALARA) and below regulatory limits, the quantity of activity discharged to the environment. The industrial PUREX process recovers the fissile material U(VI) and Pu(IV) to re-use them for the fabrication of new fuel elements e.g. recycling plutonium as a Mixed Oxide (MOX) fuel or recycling uranium for new enrichment for Pressurized Water Reactor (PWR). Meanwhile the separation of the waste (activation and fission product) is performed as a function of their pollution in order to store and avoid any potential danger and release towards the biosphere. Raffinate, that remains after the extraction step and which contains mostly all fission products and minor actinides is vitrified, the glass package being stored temporarily at the recycling plant site. Hulls and end pieces coming from PWR recycled fuel are compacted by means of a press leading to a volume reduced to 1/5th of initial volume. An organic waste treatment step will recycle the solvent, mainly tri-butyl phosphate (TBP) and some of its hydrolysis and radiolytic degradation products such as dibutyl phosphate (HDPB) and monobutyl phosphate (H2MBP). Although most scientific and technological development work focused on high level waste streams, a considerable effort is still under way in the area of intermediate and low level waste management. Current industrial practices for the treatment of gaseous effluents focusing essentially on Iodine-129 and Krypton-85 will be reviewed along with the development of novel technologies to extract, condition, and store these fission products. As an example, the current industrial practice is to discharge Kr-85, a radioactive gas, entirely to the atmosphere after dilution, but for the large recycling facilities envisioned in the near future, several techniques such as 1) cryogenic distillation and selective absorption in solvents, 2) ...
Date: November 1, 2010
Creator: Paviet-Hartmann, Patricia; Kerlin, William & Bakhtiar, Steven
Partner: UNT Libraries Government Documents Department

Final deactivation report on the Radioactive Gas Processing Facility, Building 3033, and the Actinide Fabrication Facility, Building 3033A, at Oak Ridge National Laboratory, Oak Ridge, Tennessee

Description: The purpose of this report is to document the condition of Buildings 3033 and 3033A, after completion of deactivation activities as outlined by the Department of Energy Office of Nuclear Materials and Facility Stabilization Program (EM-60) guidance documentation. This report outlines the activities conducted to place the facility in a safe and environmentally sound condition for transfer to the Department of Energy Office of Environmental Restoration Program (EM-40). This report provides a history and profile of Buildings 3033 and 3033A prior to commencing deactivation activities and a profile of the building after completion of deactivation activities. Turnover items, such as the Post-Deactivation Surveillance and Maintenance Plan, remaining hazardous materials, radiological controls, Safeguards and Security, quality assurance, facility operations, and supporting documentation provided in the Office of Nuclear Materials and Facility Stabilization Program (EM-60) Turnover package are discussed. Buildings 3033 and 3033A will require access to facilitate required S and M activities to maintain the building safety envelope. Buildings 3033 and 3033A were stabilized during deactivation so that when transferred to the EM-40 program, only a minimal S and M effort would be required to maintain the building safety envelope. Other than the minimal S and M activities the building will be unoccupied and the exterior doors locked to prevent unauthorized access. The building will be entered only to perform the required S and M. All materials have been removed from the building, and all utility systems, piping, and alarms have been deactivated.
Date: September 1, 1997
Partner: UNT Libraries Government Documents Department

The radioactivity of atmospheric krypton in 1949--1950

Description: The chemical element, krypton, whose principal source is the atmosphere, had a long-lived radioactive content, in the mid 1940s, of less than 5 dis. per min. per liter of krypton. In the late 1940s this had risen to values in the range of a hundred dis. per min. per liter. It is now some hundred times higher than the late 1940 values. This radioactivity is the result of the dissolving of nuclear fuel for military and civilian purposes, and the release thereby of the fission product krypton-85 (half-life 10.73 years, fission yield about 0.2%). The present largest emitter of krypton-85 is the French reprocessing plant at Cap-de-la Hague.
Date: August 1, 1997
Creator: Turkevich, A.; Winsberg, L.; Flotow, H. & Adams, R.M.
Partner: UNT Libraries Government Documents Department

Subsurface novel gas transport at the Nevada Test Site

Description: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The objective of our research was to explain the results of a groundwater pumping test done from 1975 to 1991 at the location of the nuclear test {open_quotes}Cambric{close_quotes} on the Nevada Test Site. The elution data from the pumped well indicated that krypton was delayed relative to tritium in the eluate and that less than half of the calculated Kr-85 source term was removed (though over 92% of the tritium was removed). We postulated an explanation for these observations and tested it with a mathematical model that simulated the movement of tritium and krypton at this site. The model showed that the hypothesis was consistent with the observed behavior; but the model was very sensitive to assumptions about initial radionuclide distributions and to hydrologic parameters. 1 ref.
Date: December 31, 1998
Creator: Thompson, J.L.; Guell, M.A. & Hunt, J.R.
Partner: UNT Libraries Government Documents Department

Atom trap trace analysis of krypton isotopes

Description: A new method of ultrasensitive isotope trace analysis has been developed. This method, based on the technique of laser manipulation of neutral atoms, has been used to count individual {sup 85}Kr and {sup 81}Kr atoms present in a natural krypton gas sample with isotopic abundances in the range of 10{sup {minus}11} and 10{sup {minus}13}, respectively. This method is free of contamination from other isotopes and elements and can be applied to several different isotope tracers for a wide range of applications. The demonstrated detection efficiency is 1 x 10{sup {minus}7}. System improvements could increase the efficiency by many orders of magnitude.
Date: November 17, 1999
Creator: Bailey, K.; Chen, C. Y.; Du, X.; Li, Y. M.; Lu, Z.-T.; O'Connor, T. P. et al.
Partner: UNT Libraries Government Documents Department

Atom trap trace analysis

Description: A new method of ultrasensitive trace-isotope analysis has been developed based upon the technique of laser manipulation of neutral atoms. It has been used to count individual {sup 85}Kr and {sup 81}Kr atoms present in a natural krypton sample with isotopic abundances in the range of 10{sup {minus}11} and 10{sup {minus}13}, respectively. The atom counts are free of contamination from other isotopes, elements,or molecules. The method is applicable to other trace-isotopes that can be efficiently captured with a magneto-optical trap, and has a broad range of potential applications.
Date: May 25, 2000
Creator: Lu, Z.-T.; Bailey, K.; Chen, C.-Y.; Du, X.; Li, Y.-M.; O'Connor, T. P. et al.
Partner: UNT Libraries Government Documents Department

Capability of environmental sampling to detect undeclared cask openings

Description: The goal of this study is to determine the signatures that would allow monitors to detect diversion of nuclear fuel (by a diverter) from a storage area such as a geological repository. Due to the complexity of operations surrounding disposal of spent nuclear fuel in a geologic repository, there are several places that a diversion of fuel could take place. After the canister that contains the fuel rods is breached, the diverter would require a hot cell to process or repackage the fuel. A reference repository and possible diversion scenarios are discussed. When a canister is breached, or during reprocessing to extract nuclear weapons material (primarily Pu), several important isotopes or signatures including tritium, {sup 85}Kr, and {sup 129}I are released to the surrounding environment and have the potential for analysis. Estimates of release concentrations of the key signatures from the repository under a hypothetical diversion scenario are presented and discussed. Gas analysis data collected from above-ground storage casks at Idaho National Engineering and Environmental Laboratory (INEEL) Test Area North (TAN) are included and discussed in the report. In addition, LANL participated in gas sampling of one TAN cask, the Castor V/21, in July 1997. Results of xenon analysis from the cask gas sample are presented and discussed. The importance of global fallout and recent commercial reprocessing activities and their effects on repository monitoring are discussed. Monitoring and instrumental equipment for analysis of the key signature isotopes are discussed along with limits of detection. A key factor in determining if diversion activities are in progress at a repository is the timeliness of detection and analysis of the signatures. Once a clandestine operation is suspected, analytical data should be collected as quickly as possible to support any evidence of diversion.
Date: December 1, 1997
Creator: Beckstead, L.W.; Efurd, D.W.; Hemberger, P.H.; Abhold, M.E. & Eccleston, G.W.
Partner: UNT Libraries Government Documents Department

Partitioning of krypton-85 in liquid scintillation cocktail

Description: Krypton is one of the noble gases. As such, it forms compounds only with exceptionally strong oxidizing agents. The concentration of krypton in air is 1.139 parts per million by volume. In general, its behavior is best described as that of an ideal gas. Krypton-85 is the longest lived of the common radioactive noble gases with a half life of 10.72 years. Gamma radiation at 513.990 keV has an intensity of only 0.434%. Most decay is {beta}{sup -} emission with a maximum energy of 687.0 keV and an average energy of 251.4 keV. The analytical chemistry of krypton-85 is driven by these factors. High concentrations may be gamma counted directly. Low levels are typically determined by more sensitive techniques such as liquid scintillation counting (LSC) where detection limits on the order of 1 picocurie (pCi) are routinely achieved. For a 5 standard cubic centimeter (scc) sample, this represents a concentration of 0.2 pCi/scc, well below the DOE Air Immersion Derived Concentration Guideline (G) of 3 pCi/scc. As a gas, krypton in a sealed LSC vial distributes itself between the liquid phase and the gas phase. Some past work has used gamma counting at levels many orders of magnitude greater than those now achievable by LSC to study the distribution of krypton. This effect is of interest in the analytical chemistry of krypton-85 because geometrical considerations influence how much of the material in the gas phase decays generating particles which then impact the liquid phase where they may be counted.
Date: December 1, 1994
Creator: Hohorst, F. A. & Sherlock, M. A.
Partner: UNT Libraries Government Documents Department

THE DIFFUSION OF KRYPTON-85 FROM URANIUM DIOXIDE POWDER

Description: The diffusion of Kr/sup 85/ in two UO/sub 2/ powders was studied by performing a series of post-irradiation anneals on the powders. The emanation data were analyzed by considering the effect of sintering as well as the effect of a distribution of particle sizes within the sample. Measurements were made at 900 to 1500 deg C. The time at a temperature was between 8 and 24 hours. The diffusion coefficients for Kr/sup 85/ in the two powders are represented by the equations: D = 2.65 x 10/sup -4/ exp - 65,500/RT for UO/sub 2/ prepared from crushed UO/sub 2/ pellets and, for a chemically prepared UO/sub 2/ powder, D = 4.9 x 10/sup -4/ exp - 73,800/RT. (auth)
Date: February 1, 1960
Creator: Auskern, A.B.
Partner: UNT Libraries Government Documents Department

Final Report on the Pinot Experiment

Description: The Pinot Project was designed to provide some indication of the extent to which gases from a confined underground explosion in oil shale would migrate parallel to the bedding planes. At 0800 on Aug. 2, 1960, 946 lb of nitromethane was fired in shot hole No. 1. There was no visible damage to the mine adit or to any structure associated with cation of the extent to which gases from a confined underground explosion in oil shale would migrate parallel to the bedding planes. At 0800 on Aug. 2, 1960, 946 lb of nitromethane was fired in shot hole No. 1. There was no visible damage to the mine adit or to any stnucture associated with the workings. Gas samples collected from sampling holes near the shot hole were analyzed for Kr/sup 85/, which had been included with the nitromethane as a tracer. It appeared that the Kr/sup 85/ concentration in the samples out to 50 ft was more or less independent of space and time between +2 and +50 hr. Relativsly little Kr/sup 85/ was detected at 125 ft and none beyond. About (20 plus or minus 10)% of the Kr/sup 85/ escaped into ths adit. The results of the Pinot experiment cannot be extrapolated quantitatively to the case of a nuclear explosion in oil shale. Even if the structure at the Pinot site is typical of oil shale, the generation of a smaller quantity of noncondensible gases per unit energy in a nuclear explosion (as compared with a chemical explosion), the shonter time scale of the ensrgy release and the higher temperatares and pressures encountered will all have a definite influence on the effective containment distance. One can conclude, however, that, if the medium at the site of a potential nuclear experiment is similar to that at Pinot, ...
Date: December 27, 1960
Creator: Adelman, F. L.; Bacigalupi, C. M. & Momyer, F. F.
Partner: UNT Libraries Government Documents Department

Mound Laboratory Progress Report for May 1963

Description: Progress is reported on research directed toward. the development of adhesives, which are compatible with explosives; the measurement of nuclear properties of polonium isotopes; residue adsorption; separation and purification of isotopes; thermal diffusion theory analyses; emission strength analyses for neutron sources; and krypton-85 counting methods development. (B.O.G.)
Date: May 31, 1963
Creator: Eichelberger, J. F.; Grove, G. R.; Jones, L. V. & Rembold, E. A.
Partner: UNT Libraries Government Documents Department

Light water reactor fuel reprocessing: dissolution studies of voloxidized and nonvoloxidized fuel

Description: Small-scale tests with irradiated Zircaloy-clad fuels from Robinson, Oconee, Saxton, and Point Beach reactors with burnups from about 200 to 28,000 MWD/MTHM have been made to determine the dissolution behavior of both voloxidized (U{sub 3}O{sub 8}) and nonvoloxidized (UO{sub 2}) fuel. No significant technical problems were encountered in batch-dissolving of either form. Dissolution rates were well-controlled in all tests. Significant characteristics of U{sub 3}O{sub 8} dissolution that differed from UO{sub 2} dissolution included: (1) reduced tritium and ruthenium ({sup 106}Ru) concentrations in product solutions, (2) increased insoluble noble metal fission product residue (about 2.2X greater), and (3) increased insoluble plutonium in the fission product residue. The insoluble plutonium is easily leached from the residue by 10M HNO{sub 3}. The weight of the fission product residue collected from both U{sub 3}O{sub 8} and UO{sub 2} fuels increased aproximately linearly with fuel burnup. A major fraction (>83%) of the {sup 85}Kr was evolved from U{sub 3}O{sub 8} fuel during dissolution rather than voloxidation. The {sup 85}Kr evolution rate was an appropriate monitor of fuel dissolution rate. Virtually all of the {sup 129}I was evolved by air sparging of the dissolver solution during dissolution. 30 tables, 18 figures.
Date: April 1, 1980
Creator: Johnson, D. R. & Stone, J. A.
Partner: UNT Libraries Government Documents Department

Radionuclide air emissions. Annual report for calendar year 1997

Description: A description is provided of radioactive effluent releases from the Pinellas Plant. The DOE sold the Pinellas Plant in March 1995. A portion of the plant was backed by DOE until September 1997 to facilitate a safe transition to commercial ventures.The plant`s radiological processing equipment was cleaned from past DOE operations. Emissions from the cleanup activity were monitored.
Date: August 1, 1997
Partner: UNT Libraries Government Documents Department

Head-end reprocessing studies of H.B. Robinson-2 fuel: II. Parametric voloxidation studies

Description: A series of hot-cell tests was conducted with UO{sub 2} that had been irradiated to an average of 28,000 MWd/t in the H.B. Robinson-2 reactor of the Carolina Power and Light Company. The tests examined the effects of temperature and of the rate of oxygen supply on the release of gaseous and semivolatile fission products, while the fuel fragments were tumbled at 12 rpm during voloxidation - the high-temperature oxidation of UO{sub 2} to U{sub 3}O{sub 8}. The experiments showed that >99.9% of the tritium in the irradiated UO{sub 2} was released to the off-gas stream at temperatures of 480 and 550{sup 0}C and at oxygen feed rates ranging from 0.1 to 1.2 mol/h. The release of {sup 85}Kr varied from 2 to 7% of the fuel inventory. The U{sub 3}O{sub 8} product ({similar_to}99% smaller than 44 {mu}m) was easily dissolved in 7 M HNO{sub 3}. One 2-h leach in 7 M HNO{sub 3} dissolved {similar_to}99.5% of the heavy metals; a second 2-h leach in 7 M HNO{sub 3} brought the total to >99.98%. Voloxidation did not affect the final solubility of the uranium and plutonium but did increase the weight of the insoluble fission product residue from 0.18% of the irradiated UO{sub 2} to {similar_to}0.62%.
Date: May 1, 1980
Creator: Goode, J.H.; Stacy, R.G. & Vaughen, V.C.A.
Partner: UNT Libraries Government Documents Department