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Afterheat calculations for the HTGR

Description: Afterheat rates were calculated for the HTGR utilizing new input information. The new afterheat results are a few percent higher than the HTGR afterheat results previously obtained in the 100-to 10,000-sec time range and are 11 to 15% higher than the previous results in the one-day to ten-days time range. The uncertainties were studied in the time region from 100 sec to ten days. The new results were also compared with calculations at other laboratories. The gamma-ray spectra were computed at s… more
Date: November 1, 1973
Creator: Sund, R.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alpha and spontaneous fission half-lives of /sup 242/Pu

Description: The alpha and spontaneous fission half-lives of /sup 242/Pu are measured relative to the alpha half-life of /sup 239/Pu. If the alpha half-life of /sup 239/Pu is 24290 +- 70 y, the /sup 242/Pu alpha half-life is (3.736 +- .029) x 10/sup 5/ y and the spontaneous fission half-life is (6.79 +- .04) x 10/sup 10/ y.
Date: December 1, 1977
Creator: Meadows, J. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Alpha-decay studies in the lead region

Description: Alpha particle emission was observed for the new isotopes /sup 184/ /sup 185/Tl as well as for the previously known nuclides /sup 186/ /sup 187/Tl. Also determined were the alpha decay half-lives for lead isotopes with A less than or equal to 192. 8 references. (JFP)
Date: January 1, 1979
Creator: Toth, K.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analytical methods for fissionable material determinations in the nuclear fuel cycle. Progress report, October 1, 1976--September 30, 1977

Description: Development of dissolution techniques for difficult-to-dissolve nuclear materials, development of methods and automated instruments for plutonium and uranium determinations, preparation of plutonium-containing materials for the Safeguards Analytical Laboratory Evaluation (SALE) program, analysis of SALE uranium materials, preparation of certified reference material plutonium metal, measurement of longer plutonium isotope half-lives, and study of ion exchange behavior of elements in various medi… more
Date: January 1, 1978
Creator: Waterbury, G.R. (comp.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analytical methods for fissionable materials in the nuclear fuel cycle. Progress report, July 1, 1975--September 30, 1976

Description: Progress continued on development of dissolution techniques for difficult-to-dissolve nuclear materials, development of methods and automated instruments for determinations of plutonium and uranium, preparation of plutonium-containing materials for the Safeguards Analytical Laboratory Evaluation (SALE) program, analysis of SALE uranium materials, and measurement of plutonium isotope half-lives. Gas-solid reactions at elevated temperatures using reactive gases such as chlorine continue to show p… more
Date: December 1, 1976
Creator: Waterbury, G. R. (comp.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Beta decays of /sup 126/Cd and /sup 126/In to levels in /sup 126/In and /sup 126/Sn. [J,. pi. ]

Description: A study of the beta decays of /sup 126/Cd and /sup 126/In using the TRISTAN on-line isotope separator facility is reported. Gamma-ray singles measurements were made for both decays usng Ge(Li) and LEPS (low energy photon spectrometer) detectors. In addition, gamma--gamma coincidence measurements and gamma multiscale measurements were made for both decays using Ge(Li) detectors. The half-life for /sup 126/Cd was determined to be 0.506 +- 0.015 sec., and the half-lives for the low- and high-spin … more
Date: January 1, 1979
Creator: Gartner, M.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparison of rats and dogs exposed to /sup 239/PuO/sub 2/

Description: Rats and dogs inhaled aerosols of /sup 239/PuO/sub 2/ at comparable ages relative to their lifespan. Both received a single exposure. The estimated lung doses at death in dogs were between 1100 and 11,000 rad. From two inhalation experiments, rats receiving doses in this range were chosen from the high-level exposed animals for comparison. Based on this data base, several comparisons were investigated. Metabolism of the material was compared for all animals and for animals which developed lung … more
Date: January 1, 1979
Creator: Mahaffey, J. A.; Sanders, C. L.; Park, J. F. & Dagle, G. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Critical concentrations of cadmium in human liver and kidney measured by prompt-gamma neutron activation

Description: Few data exist on Cd metabolism in human beings. In particular, data are needed on the role of parameters such as age, sex, weight, diet, smoking habits, and state of health. Prompt-gamma neutron activation analysis (PGNAA) provides the only currently available means for measuring in vivo levels of liver and kidney Cd. The method employs an 85 Ci, /sup 235/Pu,Be neutron source and a gamma ray detection system consisting of two Ge(Li) detector. The dose delivered to the liver and left kidney is … more
Date: January 1, 1979
Creator: Cohn, S.H.; Vartsky, D.; Yasumura, S.; Zanzi, I. & Ellis, K.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Decay Scheme Information for Analysis of Radiochemistry Foil Measurements

Description: For the radioactivities that are to be observed in the foils in these packets, the available decay scheme literature has been reviewed. Values are presented for the half-lives and the gamma-rays energies and absolute intensities for from one to three prominent transitions from each isotope. The uncertainties (1 δ value) are given for each quantity.
Date: June 1, 1972
Creator: Helmer, R. G.; Greenwood, R. C. & McElroy, W. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Decay studies of a long lived high spin isomer of /sup 210/Bi

Description: A source of approximately 30 ..mu..g of pure (> 90%) /sup 210m/Bi (J..pi.. = 9-) was prepared by irradiating /sup 209/Bi in a nuclear reactor. After chemical separations to remove /sup 210/Po from the irradiated bismuth sample were completed, the /sup 210/Bi was electromagnetically separated from the /sup 209/Bi by a series of two isotope separations to create the source mentioned above. This source was then used to conduct alpha, conversion electron, gamma, gamma-gamma coincidence, and alpha-g… more
Date: August 1, 1976
Creator: Tuggle, D. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Delayed neutron emission from mass-separated fission products

Description: Thesis. Delayed neutron characteristics of six fission product nuclides were determined using a mass separator operated on-line with a nuclear reactor. Beta-decay half-lives were- measured using neutron multiscaling techniques for the precursors /sup 88/Br, /sup 89/Br, /sup 98/Kr, /sup 93/Kr, /sup 137/I, and / sup 138/I. The observed half-lives were 16.52 plus or minus .17 seconds, respectively.. Energy spectra were measured for delayed neutrons emitted in the beta-decays of /sup 17/N, /sup 137… more
Date: February 1, 1974
Creator: Norman, J.H.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Discovery of a 7. 6-hour high-spin isomer of einsteinium-256

Description: A 7.6-hour, beta-emitting isomer of /sup 256/Es has been produced via the (t,p) reaction by bombarding /sup 254g/Es with 16-MeV tritons. No evidence for an alpha branch was found. A number of gamma rays were observed, on the basis of which a partial decay scheme is proposed. It is concluded that the isomer has spin 7 or 8.
Date: January 1, 1976
Creator: Hoffman, D. C.; Daniels, W. R.; Wilhelmy, J. B.; Bunker, M. E.; Starner, J. W.; Jackson, S. V. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Discovery of fermium-259. [Half life, cross sections]

Description: A 1.5-sec spontaneous fission activity was produced by irradiation of /sup 257/Fm with 16-MeV tritons at the Los Alamos Tandem Van de Graaff Facility. On the basis of cross section and fission systematics, this 1.5-sec activity was attributed to /sup 259/Fm formed by the reaction, /sup 257/Fm(t,p)/sup 259/Fm. /sup 259/Fm is the heaviest known isotope of fermium and has more neutrons than any other isotope so far identified. The mass distribution of the /sup 259/Fm is highly symmetric and the av… more
Date: January 1, 1976
Creator: Hoffman, D. C.; Weber, J.; Wilhelmy, J. B.; Hulet, E. K.; Landrum, J. H.; Lougheed, R. W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effect of physico-chemical properties on metabolism of transuranium oxide aerosols inhaled by beagle dogs

Description: The oxides of four transuranium isotopes ($sup 238$Pu, $sup 239$Pu, $sup 241$Am, and $sup 244$Cm), prepared by identical methods of calcining the oxalate at 750$sup 0$C for two hours, had different physico-chemical properties. For all four oxides the density ranges from 9.8 to 11.4 g cm$sup -3$ and initial ultrafilterability (suspended fraction of activity less than 24 A) varied from 0.002 percent for $sup 239$PuO$sub 2$ to 2.24 percent for $sup 238$PuO$sub 2$. Dogs were exposed by nose-only te… more
Date: January 1, 1975
Creator: Craig, D. K.; Park, J. F. & Ryan, J. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

ENDF/B-IV fission-product files: summary of major nuclide data

Description: The major fission-product parameters [sigma/sub th/, RI, tau/sub 1/2/, E- bar/sub $beta$/, E-bar/sub $gamma$/, E-bar/sub $alpha$/, decay and (n,$gamma$) branching, Q, and AWR] abstracted from ENDF/B-IV files for 824 nuclides are summarized. These data are most often requested by users concerned with reactor design, reactor safety, dose, and other sundry studies. The few known file errors are corrected to date. Tabular data are listed by increasing mass number. (auth)
Date: September 1, 1975
Creator: England, T. R. & Schenter, R. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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