24 Matching Results

Search Results

Advanced search parameters have been applied.

Development of a diagnostic model for inhaled promethium-147 oxide: animal studies

Description: Rats and beagle dogs were exposed by inhalation to an aerosol containing stable Sm$sub 2$O$sub 3$ tagged with $sup 145$Sm$sub 2$O$sub 3$ and $sup 143$Pm$sub 2$O$sub 3$. The animals were sacrificed at 0, 14 and 30 days post- exposure to compare the kinetics and translocation of $sup 145$Sm and $sup 143$Pm. Quantitative analysis for $sup 145$Sm and $sup 143$Pm in several tissues and excreta indicate that the two rare earth elements were mobilized and distributed similarly by the rats and dogs. Results indicate that within the error of the measurement technique, samarium acts as a carrier for promethium. The data also indicate that activities measured in fecal samples could be used to predict lung burdens of $sup 147$Pm. At activity levels and sintering temperatures employed in the rat exposures, there was sufficient activity in urine samples to permit its use as an indicator of lung burdens of $sup 147$Pm. At activity levels and sintering temperatures employed in the dog exposures, this was not the case. (auth)
Date: January 1, 1975
Creator: Shipler, D.B.; Ballou, J.E.; Griffin, B.I. & Nelson, I.C.
Partner: UNT Libraries Government Documents Department


Description: 7 = 9 9 9 9 7 7 7 = 9 9 9 95 : > @ 9 ; 5 8 @ = K : . ighpurity Nb deformed by impact or slow compression at - 196 deg C. An apparent phase transformation was detected in high- purity Ga deformed at 4.2 deg K. The specific heat of the group IV-A metals and alloys of Zr-In and Zr-Sn were measured from 1.2 to 4.5 deg K. In the Zr-rich portion of the Zr-Ga phase diagram, the alpha / beta phase boundaries of Zr are depressed by additions of Ga and the beta phase decomposes by a eutectoid reaction. The Cd pressures of alpha - and beta - Zr alloys containing 1 to 11% Cd were measured between 1090 and 1325 deg K. Crystal structures of several unreported transition-metal fluorides, rare-earth hydrides and nitrides were determined. Progress in the study of phase transitions in beta -quenched Zr-Nb alloys aged below the eutectoid temperature is reported. A high-temperature investigation of the order-disorder phase transition of a Cu31 at.% Au alloy has revealed an intermediate periodic antiphase condition. A previously described x- raydiffraction technique for the measurement of the thickness and strain of thin oxide films was applied to a series of five Cu/sub 2/O films grown on Cu single crystals. A new x-raydiffraction method for measuring film thickness, based on the integrated intensities of the Bragg maxima, is shown to agree very well with the thickness as determined from the line-shape analysis. A determination was made of the influence which electrostatic interactions with neighboring ions have on the energy n yields pi transition in the nitrate ion. Some information on the behavior of solute species in dilute solutions of Bi in BiCl/sub 3/ was obtained from absorption spectra. Studies of the gaseous ...
Date: December 16, 1959
Partner: UNT Libraries Government Documents Department


Description: The radiation intensities from shielded and unshielded sources fabricated from seventeen isotopes that show promise for use in isotopic power or radiation applications were calculated. Source sizes in the range of 100 to 20,000 thermal watts were evaluated. All shielded sources were assumed to be attenuated by Fe, Pb, and U; and in those cases where the source also emitted neutrons, neutron and gamma attenuation through water was determined. The isotopes studied and their physical form are as follows: /sup 60/Co (metal), /sup 85/Kr (liquefied gas), /sup 90/Sr (oxide and titanate), Zr-/sup 95/Nb (oxide), / sup 106/Ru (metal), /sup 137/Cs (glass), /sup 144/Ce (ox ide), /sup 147/Pm (oxide), /sup 170/Tm and /sup 171/Tm (both as oxides), /sup 204/Tl (metal), /sup 210/Po (metal matrix with void space for gas collection), /sup 232/U (oxide), /sup 228/Th (oxide matrix with void space for gas collection), /sup 238/Pu (oxide), /sup 242/Cm (oxide matrix with void space for gas collection), and / sup 244/Cm (oxide). The use of the graphical results to calculate separation distance, shield thickness, and shield weight is demonstrated. (auth)
Date: April 1, 1964
Creator: Arnold, E.D.
Partner: UNT Libraries Government Documents Department