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Management of radioactive waste gases from the nuclear fuel cycle. Volume I. Comparison of alternatives

Description: Alternatives were compared for collection and fixation of radioactive waste gases released during normal operation of the nuclear fuel cycle, and for transportation and storage/disposal of the resulting waste forms. The study used a numerical rating scheme to evaluate and compare the alternatives for krypton-85, iodine-129, and carbon-14; whereas a subjective evaluation, based on published reports and engineering judgement, was made for transportation and storage/disposal options. Based on thes… more
Date: December 1, 1980
Creator: Evans, A. G.; Prout, W. E.; Buckner, J. T. & Buckner, M. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Experiments with a lime slurry in a stirred tank for the fixation of carbon-14-contaminated CO/sub 2/ from simulated HTGR fuel reprocessing off-gas

Description: The fixation of CO/sub 2/ with a lime slurry in a stirred tank reactor appears to be feasible. The rate of reaction is fast, and virtually complete removal of CO/sub 2/ can be attained. At a gas residence time of <1 min, the decontamination factor (DF) is >100 in a single stage reactor for CO/sub 2/ concentrations ranging from 5 to 100%. It has been determined that two-stage contacting sequences which result in a cumulative DF > 10/sup 4/ are feasible. The reaction rate is constant up … more
Date: March 1, 1978
Creator: Holladay, D. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Size distribution of autotrophy and microheterotrophy in reservoirs: implications for foodweb structure

Description: Particle size is a primary determinant of resources available to consumers and of the efficiency of energy transfer through planktonic food chains. Dual radioisotopic labeling (with /sup 14/C-bicarbonate and /sup 3/H-acetate) and size fractionation of naturally-occurring phytoplankton-bacterioplankton assemblages were employed to examine the particle size distributions of planktonic autotrophy and microheterotrophy in four limnologically-dissimilar US reservoirs (Lake Mead, Arizona-Nevada, olig… more
Date: January 1, 1981
Creator: Kimmel, B. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Excision repair of bulky lesions in the DNA of mammalian cells

Description: The report examines the process of excision repair of pyrimidine dimers from uv-irradiated and chemically challenged human cells. It is shown by means of a sensitive endonuclease assay that the amount of excision observed depends upon the isotope used to label cells, and that XP heterozygotes are between normals and XPs. (ACR)
Date: January 1, 1980
Creator: Setlow, R B & Grist, E
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Voloxidation studies with UO/sub 2/ reactor fuels

Description: Voloxidation was studied experimentally in small-scale laboratory tests with irradiated UO/sub 2/ reactor fuels. The present study developed new data on the effects on the voloxidation reaction of hull length, oxygen concentration, temperature, agitation, fuel density, and fuel type and burnup. The reaction was studied by measuring weight gains, yields of U/sub 3/O/sub 8/, product densities and particle-size distributions, reaction rates, tritium release, and behavior of other off-gases (/sup 1… more
Date: January 1, 1980
Creator: Stone, J A
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of Lime-Slurry Stirred Tank Carbonation Reactor

Description: Gas residence time distributions were determined for a stirred tank carbonation reactor. Empirical correlations for the first and second moments of the residence time distribution (RTD) curves as functions of flow rates and impeller speeds were obtained. Decontamination factors for /sup 85/Kr were measured.
Date: September 23, 1977
Creator: McAleese, J. P.; Belt, B. A.; Datesh, J. R. & Shaeffer, M. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Calibration and testing or models of the global carbon cycle

Description: A ten-compartment model of the global biogeochemical cycle of carbon is presented. The two less-abundant isotopes of carbon, /sup 13/C and /sup 14/C, as well as total carbon, are considered. The cycling of carbon in the ocean is represented by two well-mixed compartments and in the world's terrestrial ecosystems by seven compartments, five which are dynamic and two with instantaneous transfer. An internally consistent procedure for calibrating this model against an assumed initial steady state … more
Date: January 1, 1980
Creator: Emanuel, W.R.; Killough, G.G. & Shugart, H.H. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Gamow-Teller sum rules and the /sup 14/C(/sup 6/Li,/sup 6/He)/sup 14/N reaction. [62 MeV]

Description: A correlation between the (/sup 6/Li,/sup 6/He) cross sections and the Gamow-Teller strength observed previously for other targets persists in the /sup 14/C(/sup 6/Li,/sup 6/He) reaction. The total G.T. strength up to 12 MeV excitation is measured, and sum rules for the G.T. strength that depend on the LS configurations of the target state are derived. The extracted LS configuration of the /sup 14/C ground state is in serious disagreement with shell model calculations. There are several inconsi… more
Date: January 1, 1977
Creator: Wharton, W. R.; Goodman, C. D. & Hensley, D. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Long-lived light mass element half-lives (A < 125)

Description: Reported values of half-lives of light and intermediate mass elements are evaluated. The evaluation analysis estimates the systematic error and the resulting standard deviation. Recommended values are then presented for tritium, /sup 10/Be, /sup 14/C, /sup 26/Al, /sup 39/Ar, /sup 40/K, /sup 50/V, /sup 53/Mn, /sup 76/Ge, /sup 87/Rb, /sup 92/Nb, /sup 107/Pd, /sup 113/Cd, /sup 115/In, and /sup 123/Te. 106 refs., 15 tabs. (WRF)
Date: January 1, 1985
Creator: Holden, Norman E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Light mass elements total half-lives for selected long-lived nuclides

Description: In the past, many compilations and evaluations of half-lives have been made which have uncritically accepted authors' values and uncertainties. They have merely recommended weight-averaged reported results. This evaluation attempts to reanalyze each experiment in the literature including an estimate of the standard deviation utilizing, where possible, an estimate of the systematic error. This paper constitutes a preliminary step in the process of recommending values. The long-lived nuclides of … more
Date: January 1, 1985
Creator: Holden, Norman E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Establishing release limits for /sup 3/H, /sup 14/C, /sup 85/Kr, and /sup 129/I

Description: Tritium (/sup 3/H), /sup 14/C, /sup 85/Kr, and /sup 129/I are the most important globally dispersed radionuclides released from the nuclear fuel cycle. In this paper, we investigate whether global transport of these radionuclides could also be important in assessing doses to individuals in critical groups of the population.
Date: January 1, 1983
Creator: Kocher, D. C. & Killough, G. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of barium hydroxide and calcium hydroxide slurry carbonation reactors

Description: The removal of CO/sub 2/ from air was investigated by using a continuous-agitated-slurry carbonation reactor containing either barium hydroxide (Ba(OH)/sub 2/) or calcium hydroxide (Ca(OH)/sub 2/). Such a process would be applied to scrub /sup 14/CO/sub 2/ from stack gases at nuclear-fuel reprocessing plants. Decontamination factors were characterized for reactor conditions which could alter hydrodynamic behavior. An attempt was made to characterize reactor performance with models assuming both… more
Date: May 1, 1980
Creator: Patch, K.D.; Hart, R.P. & Schumacher, W.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Energy and technology review, May--June 1991

Description: This issue of Energy and Technology Review describes two powerful analytical tools that use ion-beam techniques to make contributions to an astonishing range of fundamental problems. We characterize these techniques -- accelerator mass spectrometry (AMS) and ion microbeam analysis -- under the common rubric of accelerator microanalysis. Each of these tools is used in disciplines ranging from anthropology to zoology. The rich diversity of applications is reason enough to dedicate an entire issue… more
Date: January 1, 1991
Creator: Johnson, K.C.; de Vore, L.; Gleason, K.; Highstone, H.; Kroopnick, H.; Sanford, N.M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Evaluation of oxidation techniques for preparing bioassay and environmental samples for liquid scintillation counting

Description: In environmental and biological monitoring for carbon-14 and tritium, the presence of color and chemical quenching agents in the samples can degrade the efficiency of liquid scintillation counting. A series of experiments was performed to evaluate the usefulness, under routine conditions, of first oxidizing the samples to improve the counting by removing the color and quenching agents. The scintillation counter was calibrated for the effects of quenching agents on its counting efficiency. Oxidi… more
Date: October 1, 1979
Creator: Miller, H.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analytical methods for predicting contaminant transport

Description: This paper summarizes some of the previous and recent work at the University of California on analytical solutions for predicting contaminate transport in porous and fractured geologic media. Emphasis is given here to the theories for predicting near-field transport, needed to derive the time-dependent source term for predicting far-field transport and overall repository performance. New theories summarized include solubility-limited release rate with flow backfill in rock, near-field transport… more
Date: September 1, 1989
Creator: Pigford, T.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The impact of changing land use, nitrate deposition and CO sub 2 fertilization on soil carbon storage

Description: This research strives to assess the impact of changing land use, nitrate deposition and CO{sub 2} fertilization on soil carbon storage. Our motivation is that this reservoir is the most likely candidate for the so-called missing carbon sink. We are working on several aspects of this problem by measuring carbon content, nitrogen content and radiocarbon ratios in paired soil samples from neighboring sites, to determine the impact of land use on soil carbon inventories and turnover times. We are a… more
Date: May 21, 1992
Creator: Harrison, K. & Broecker, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gas flow in and out of a nuclear waste container

Description: We analyze the flow of gases out of and into a high-level-waste container in the unsaturated tuff of Yucca Mountain. Containers are expected to fail eventually by localized cracks and penetrations. Even though the penetrations may be small, argon gas initially in the hot container can leak out. As the waste package cools, the pressure inside the container can become less than atmospheric, and air can leak in. {sup 14}C released from the hot fuel-cladding surface can leak out of penetrations, an… more
Date: May 1, 1989
Creator: Zwahlen, E. D.; Pigford, T. H.; Chambre, P. L. & Lee, W. W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear waste management quarterly progress report, April--June 1977

Description: Progress is reported in sections on decontamination and densification of chop-leach cladding residues, monitoring methods for effluents from waste solidification, TRU waste fixation studies, krypton solidification, /sup 14/C and /sup 129/I fixation, waste management system studies, waste isolation assessment, stored waste migration monitoring, properties of fission product organic complexes, and decontamination of metals. (JRD)
Date: November 1, 1977
Creator: Platt, A.M. (comp.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Use of the small gas proportional counters for the carbon-14 measurement of very small samples

Description: Two recent developments are: the first is the mass-spectrometric separation of /sup 14/C and /sup 12/C ions, followed by counting of the /sup 14/C, while the second is the extension of conventional proportional counter operation, using CO/sub 2/ as counting gas, to very small counters and samples. Although the second method is slow (months of counting time are required for 10 mg of carbon) it does not require operator intervention and many samples may be counted simultaneously. Also, it costs o… more
Date: January 1, 1981
Creator: Sayre, E.V.; Harbottle, G.; Stoenner, R.W.; Otlet, R.L. & Evans, G.V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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