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Developing optical traps for ultra-sensitive analysis

Description: The authors describe the coupling of a magneto-optical trap to a mass separator for the ultra-sensitive detection of selected radioactive species. As a proof of principle test, they have demonstrated the trapping of {approximately} 6 million {sup 82} Rb (t{sub 1/2} = 75 s) atoms using an ion implantation and heated foil release method for introducing the sample into a trapping cell with minimal gas loading. Gamma-ray counting techniques were used to determine the efficiencies of each step in th… more
Date: September 1, 1998
Creator: Zhao, X.; Vieira, D.J.; Guckert, R. & Crane, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Preliminary integrated calculation of radionuclide cation and anion transport at Yucca Mountain using a geochemical model

Description: This paper presents preliminary transport calculations for radionuclide movement at Yucca Mountain using preliminary data for mineral distributions, retardation parameter distributions, and hypothetical recharge scenarios. These calculations are not performance assessments, but are used to study the effectiveness of the geochemical barriers at the site at mechanistic level. The preliminary calculations presented have many shortcomings and should be viewed only as a demonstration of the modeling… more
Date: November 1, 1989
Creator: Birdsell, K. H.; Campbell, K.; Eggert, K. G. & Travis, B. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A repository released-dose model for the evaluation of long-lived fission product transmutation effectiveness

Description: A methodology has been developed to quantify the total integrated dose due to a radionuclide species i emplaced in a geologic repository; the focus is on the seven long-lived fission products (LLFPs). The methodology assumes continuous exposure water contaminated with species i at the accessible environment (i.e., just beyond the geologic barrier afforded by the geologic repository). The dose integration is performed out to a reference post-release time. The integrated dose is a function of the… more
Date: July 1, 1995
Creator: Davidson, J. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Simulation of radionuclide retardation at Yucca Mountain using a stochastic mineralogical/geochemical model

Description: This paper presents preliminary transport calculations for radionuclide movement at Yucca Mountain. Several different realizations of spatially distributed sorption coefficients are used to study the sensitivity of radionuclide migration. These sorption coefficients are assumed to be functions of the mineralogic assemblages of the underlying rock. The simulations were run with TRACRN{sup 1}, a finite-difference porous flow and radionuclide transport code developed for the Yucca Mountain Project… more
Date: February 1, 1990
Creator: Birdsell, K. H.; Campbell, K.; Eggert, K. & Travis, B. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High-value use of weapons-plutonium by burning in molten salt accelerator-driven subcritical systems or reactors

Description: The application of thermal-spectrum molten-salt reactors and accelerator-driven subcritical systems to the destruction of weapons-return plutonium is considered from the perspective of deriving the maximum societal benefit. The enhancement of electric power production from burning the fertile fuel {sup 232}Th with the plutonium is evaluated. Also the enhancement of destruction of the accumulated waste from commercial nuclear reactors is considered using the neutron-rich weapons plutonium. Most … more
Date: November 1, 1993
Creator: Bowman, C. D. & Venneri, F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Supernate source term analysis: Revision 1

Description: The HM Process (modified PUREX) has been used in the H-Canyon since 1959 to recover uranium and byproduct neptunium. The PUREX process has been used in the Separation facilities in F and H-Area. This report analyzes both the inhalation and ingestion radionuclide dose impact of the HM and PUREX process soluble portion of their waste streams. The spent fuel assemblies analyzed are the Mark 16B, Mar 22 for the HM process, and the Mark 31A, Mark 31B for the PUREX process. The results from this anal… more
Date: October 13, 1994
Creator: Aponte, C. I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A summary of the fission product metabolism studies up to March 1944

Description: The metabolic properties of the carrier free long lived fission products in the adult rat have been investigated at different intervals ranging from one to sixty-eight days following administration of the radioactive material. The radio elements studied include the most important long lived fission products, namely, Sr, Y, Zr, Cb, Ra, I, Xe, Cs, Ba, La, Ce, Pr, Np, and the unseparated uranium free fission mixture. The routes of administration included intraperitoneal, intramuscular, oral and in… more
Date: March 30, 1944
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiochemical analyses of several spent fuel Approved Testing Materials

Description: Radiochemical characterization data are described for UO{sub 2} and UO{sub 2} plus 3 wt% Gd{sub 2}O{sub 3} commercial spent nuclear fuel taken from a series of Approved Testing Materials (ATMs). These full-length nuclear fuel rods include MLA091 of ATM-103, MKP070 of ATM-104, NBD095 and NBD131 of ATM-106, and ADN0206 of ATM-108. ATMs 103, 104, and 106 were all irradiated in the Calvert Cliffs Nuclear Power Plant (Reactor No.1), a pressurized-water reactor that used fuel fabricated by Combustion… more
Date: September 1, 1994
Creator: Guenther, R. J.; Blahnik, D. E. & Wildung, N. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mass transfer of soluble species into backfill and rock

Description: This report describes a mathematical model that estimates the rate that cesium and iodine isotopes would migrate from spent fuel rods after emplacement in a geologic repository that is subsequently flooded with ground water. 4 refs., 2 figs. (TEM)
Date: July 1, 1986
Creator: Chambre, P. L.; Kang, C. H.; Lee, W. W. L. & Pigford, T. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

UCB-NE-107 user's manual

Description: The purpose of this manual is to provide users of UCB-NE-107 with the information necessary to use UCB-NE-107 effectively. UCB-NE-107 is a computer code for calculating the fractional rate of readily soluble radionuclides that are released from nuclear waste emplaced in water-saturated porous media. Waste placed in such environments will gradually dissolve. For many species such as actinides and rare earths, the process of dissolution is governed by the exterior flow field, and the chemical rea… more
Date: March 1, 1989
Creator: Lee, W. W. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Numerical simulation of cesium and strontium migration through sodium bentonite altered by cation exchange with groundwater components

Description: Numerical simulations have been used to investigate how spatial and temporal changes in the ion exchange properties of bentonite affect the migration of cationic fission products from high-level waste. Simulations in which fission products compete for exchange sites with ions present in groundwater diffusing into the bentonite are compared to simulations in which the exchange properties of bentonite are constant. 12 refs., 3 figs., 2 tabs.
Date: October 1, 1988
Creator: Jacobsen, J.S. & Carnahan, C.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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End of life fission product distributions in F-1 experiment fuel rods

Description: Fission product migration and end-of-life distributions were examined in the F-1 (X094) series of sealed, mixed-oxide fuel rods irradiated in the fast flux of EBR-II. Cesium, rubidium, iodine, and strontium data obtained from axial gamma scanning, mass spectrometry, and radiochemical analyses are presented. The results show significant migration of cesium, probably as both a volatile species and as the noble gas precursor. Cesium metal species leaving the fuel region accumulate predominately at… more
Date: May 1, 1980
Creator: Goodin, D. T.; Langer, S. & Bell, W. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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UO sub 2 matrix dissolution rates and grain boundary inventories of Cs, Sr, and Tc in spent LWR fuel

Description: Experimental methods have been developed for measuring the grain-boundary inventories of radionuclides and for determining whether the UO{sub 2} matrix of spent light-water reactor fuel into individual grains. With the grain boundaries thus exposed, the associated inventories of radionuclides can be completely dissolved and measured. The determine whether the UO{sub 2} matrix of spent fuels dissolves congruently, the fuel grains were placed in a flow-through column and water was pumped through … more
Date: November 1, 1990
Creator: Gray, W.J. & Strachan, D.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Isotope correlation studies relative to high enrichment test reactor fuels

Description: Several correlations of fission product isotopic ratios with atom percent fission and neutron flux, for highly enriched /sup 235/U fuel irradiated in two different water moderated thermal reactors, have been evaluated. In general, excellent correlations were indicated for samples irradiated in the same neutron spectrum; however, significant differences in the correlations were noted with the change in neutron spectrum. For highly enriched /sup 235/U fuel, the correlation of the isotopic ratio /… more
Date: June 1, 1978
Creator: Maeck, W. J.; Tromp, R. L.; Duce, F. A. & Emel, W. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Cumulative releases of radionuclides from uncontained waste packages

Description: This report describes mathematical predictions for the migration of radionuclides from an emplaced radioactive waste container. The model assumes a spherical-equivalent waste solid surrounded by backfill but neglects the effect of decay heat. 7 refs., 2 tabs. (TEM)
Date: July 1, 1986
Creator: Lee, W. W. L.; Kim, C. L.; Chambre, P. L. & Pigford, T. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Basalt-radionuclide distribution coefficient determinations. FY-1979 annual report

Description: Experimental radionuclide distribution coefficients (Kd') were determined for Pomona, Flow E, Umtanum basalts, and secondary mineralization associated with Pomona basalt at 23/sup 0/, 60/sup 0/ and 150/sup 0/C. Radionuclides used were /sup 75/Se, /sup 85/Sr, /sup 99/Tc, /sup 125/I, /sup 135/Cs, /sup 226/Ra, /sup 237/Np, /sup 238/U, /sup 241/Am, and /sup 241/Pu. Solution oxygen contents were controlled by the basalt/groundwater system (Eh = 600 to 700 mV), and were high (8.2 to 8.4 mg/l) at 23/s… more
Date: September 1, 1980
Creator: Ames, L.L. & McGarrah, J.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Assay of long-lived radionuclides in low-level wastes from power reactors

Description: The 10 CFR Part 61 waste classification system includes several nuclides which are difficult to assay without expensive radiochemical methods. In order for waste generators to classify wastes practically, NRC Staff has recommended the use of correlation factors to scale the difficult-to-measure nuclides with nuclides which can be measured more easily (i.e., gamma emitters such as /sup 60/Co or /sup 137/Cs). In this study, Science Applications International Corporation (SAIC) performed complete … more
Date: April 1, 1985
Creator: Cline, J.E.; Noyce, J.R.; Coe, L.J. & Wright, K.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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