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- Research in Radiobiology. Annual Report of Work in Progress on the Chronic Toxicity Program
- No Description Available.
- The Effect of Chronic Gamma Irradiation on Apical Dominance of Trees
- Cherry and apple trees subjected to low doses of gamma irradiation (average of 16 and 34 r/day) for 10 years produced atypical branch development and reversal of dominance which could be attributed to the decrease or inactivation of auxin resulting from the irradiation. (auth)
- Radiation Chemistry of Thymine in Aqueous Alkaline Solution
- Gamma radiolysis of thymine solutions was investigated over a wide pH range using ultraviolet absorption spectra and two-dimensional paper chromatography combined with radioautography. The results show that as the pH is increased, the spectrum change for a given dose decreases, G(H/sub 2/O/sub 2/) increases, and G(organic peroxides) decreases. Sevrral compounds were isolated from irradiated neutral or acidic solutions of thymine, while in strongly alkaline solutions, only hydroxymethyl uracil was found in appreciable amounts. It is concluded that radiolysis of un-ionized thymine (in acidic solution) proceeds by addition to the double bond, while in ionized thymine (in alkaline solution), the methyl hydrogens are more reactive. (D.L.C.)
- Reduction of Uranium Hexafluoride Retention on Beds of Magnesium Fluoride Used for Removal of Technetium Hexafluoride
- The excessive loss of uranium incurred when discarding magnesium fluoride, (the adsorber used to selectively remove technetium hexafluoride from uranium hexafluoride streams) is a problem common to all volatility processes for recovering enriched uranium fuels. As a result of the work described, two schemes for the release of the uranium hexafluoride from the magnesium fluoride and its separation from the technetium hexafluoride are proposed. One scheme depends on preferential thermal desorption of the uranium hexafluoride at 350 deg C and the other on selective adsorption of the uranium hexafluoride on sodium fluoride pellets following the codesorption of the two hexafluorides with fluorine at 500 deg C from the magnesium fluoride pellets. These proposals are aimed at reducing the amount of retained uranium to less than 1 g per 1000 g of discardable magnesium fluoride. In the work reported, the deposition of uranium on magnesium fluoride as a function of heating, fluorination, and hydrogen fluoride pretreatment of the magnesium fluoride pellets prior to exposure to uranium hexafluoride was characterized in a series of gasometric studies. The dependence of the quantity of uranium hexafluoride adsorbed on pressure and temperature was also determined. The data show that physical adsorption is the mechanism for the deposition of most of the uranium hexafluoride on well- stabilized magnesium fluoride pellets. More than 90% of the adsorbate can be removed by heating to 350 deg C. Chemisorption (formation of a double salt) is probably not involved because of the small (<0.05) mole ratio of UF/sub 6//MgF/ sub 2/ observed. (auth)
- ISOTOPIC POWER SOURCES COUPLED WITH THERMOELECTRIC CONVERTERS
- No Description Available.
- A Summary of Industrial Accidents in Usaec Facilities, 1961-1962
- Information is presented on accidents andd incidents occurring during 1961 and 1962 in plants owned and operated by the AEC. Revised reporting requirements established by the AEC in April 1962 are outlined. Data are summarized on radiation exposure of AEC contractor personnel, accidents involving radioactive materials, andd accidents involving fatalities. (C.H.)
- PROCEEDINGS OF AEROSPACE NUCLEAR SAFETY, OCTOBER 1-4, 1963, ALBUQUERQUE, NEW MEXICO
- Separate abstracts were prepared for 18 of the 28 papers presented; 8 were previously abstracted in NSA. Topics covered include safety programs and philosophy, nuclear safety aspects of SNAP desigu and of propulsion reactor design, environmental factors, and re-entry and postmission disposal. (R.E.U.)
- THERMONUCLEAR DIVISION SEMIANNUAL PROGRESS REPORT FOR PERIOD ENDING OCTOBER 31, 1963
- No Description Available.
- PROCEEDINGS OF THE THIRD PLOWSHARE SYMPOSIUM ENGINEERING WITH NUCLEAR EXPLOSIVES, APRIL 21-23, 1964
- No Description Available.