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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.
Partner: UNT Libraries Government Documents Department

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 techniques to aerosols generated by nebulizing water suspensions of the oxides. The dogs were sacrificed at intervals from one week to about a year postexposure. The rate of translocation of material from lung to other tissues increased from $sup 239$Pu to $sup 238$Pu to $sup 241$Am to $sup 244$Cm, possibly reflecting the decrease in mean particle size from an MMD of 0.7 $mu$m to $sup 239$PuO$sub 2$ to 0.6 $mu$m for $sup 238$PuO$sub 2$ to 0.4 $mu$m for $sup 241$AmO$sub 2$ to 0.1 $mu$m for $sup 244$CmO/sub x/. Accumulation of the isotopes in the liver and skeleton as a percentage of final body burden was 1 percent $sup 239$Pu and 7 to 23 percent for $sup 238$Pu at about a year postexposure, while at 270 days postexposure, values were 40 percent for $sup 241$Am and 40 to 30 percent for $sup 244$Cm. (auth)
Date: January 1, 1975
Creator: Craig, D.K.; Park, J.F. & Ryan, J.L.
Partner: UNT Libraries Government Documents Department

Tabulation of dose equivalent per microcurie-day for source and target organs of an adult for various radionuclides

Description: Data are tabulated on the radiation dose equivalent per microcurie-day for source and target organs of a human adult for 100 radionuclides. These are listed at the end of the volume. Included are several radionuclides where the parent has a daughter radionuclide of physical half-life less than five minutes. In such cases separate S tables are given for the parent and for the daughter as well as a composite table which contains S values for the parent plus S values for the daughter weighted according to the percent decay via the daughter. (CH)
Date: November 1, 1975
Creator: Snyder, W.S.; Ford, M.R.; Warner, G.G. & Watson, S.B.
Partner: UNT Libraries Government Documents Department

Nuclear decay data for selected radionuclides

Description: Contained in this report are tabulations of the atomic and nuclear radiations emitted by 194 radioactive nuclides. The nuclei included comprise most of those currently of interest in medical practice or research, health physics, industry, nuclear power, environmental impact studies, and as reference standards. Listed in tabular form are recommended values for half-lives, energies, intensities (probabilities per decay), and equilibrium absorbed-dose constants for each of the atomic and nuclear radiations emitted by these radioactive atoms. (auth)
Date: March 1, 1976
Creator: Martin, M.J. (ed.)
Partner: UNT Libraries Government Documents Department

Fallout strontium-90 and cesium-137 in northern Alaskan ecosystems during 1959--1970

Description: Thesis. Cycling routes, rates of transport, and resultant concentrations of the fallout radionuclides /sup 90/Sr and /sup 137/Cs in northern Alaskan ecosystems were defined during the period 1959 to 1970. Radiochemical analysis of extensive samples of biota and whole-body counting of / sup 137/Cs in Eskimo and Indian ethnic groups were related to ecological principles, especially the concept of trophic niche, which elucidated the observed patterns of radionuclide concentrations. Experiments involving Sr and Cs radioisotopes applied to natural Cladonia-- Cetraria lichen carpets yielded effective half-times of 1.O to 1.6 years for Sr and more than 10 years for Cs. Direct and indirect estimates of /sup 131/Cs half-times in Eskimos on a caribou meat diet were made by dietary manipulation and by relating dietary /sup 137/Cs intake and resultant change between periodic whole body counts. Effective half- times of 70 days for adults (more than 21 years old) and minors (14 to 20 years old) and of 45 days for children (less than 14 years old) were found. Suitable mathematical models were used to compute lichen forage ingestion rates of free- ranging adult caribou (4.5 to 5.0 kg dry weight per day), caribou meat ingestion rates of Anaktuvuk Pass residents (up to 2 kg wet weight per day for men), and / sup 90/Sr body burdens of Anaktuvuk Pass residents during the period 1952 to 1968 (maximum value of 8 nCi in adult males during late 1966 to early 1967). Special emphasis was made of cultural influences upon the food-gathering patterns of the native peoples studied. Culture change, especially in the form of food stamps, welfare payments, acquisition of snowmobiles, and improved housing was documented throughout the study and noticeably reduced the radionuclide accumulations. Total radiation dose rates to the Anaktuvuk Pass adult population were estimated to be about 100 mrad/year ...
Date: May 1, 1973
Creator: Hanson, W.C.
Partner: UNT Libraries Government Documents Department

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/I, /sup 93/Kr , and /sup 93/Rb. The spectra of neutron emissions in the mass 93 parentdaughter decay chain were observed using a moving tape collector to effect isobaric separation. Two different types of /sup 3/He- filled neutron spectrometer were used to determine the spectra; a proportional counter with risetime discrimination electronics, and a high resolution ionization chamber. The measured delayed, neutron spectra using both detector types are presented, and the results compared, where possible, with other reported measurements. (auth)
Date: February 1, 1974
Creator: Norman, J.H.
Partner: UNT Libraries Government Documents Department

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 several shutdown times for future applications in shielding studies. Previous afterheat calculations for the HTGR are completely replaced and updated. (auth)
Date: November 1, 1973
Creator: Sund, R.E.
Partner: UNT Libraries Government Documents Department