A process hns been developed for impregnating graphite with U/sub 3/O/ sub 8/ in connection with the proposed use of such material for fuel rod elements in the Daniels' High Temperature Pile. The process as developed consists of five steps: Fabrication of the graphite in the desired shape; Pretreatment of the graphite by boiling in water and then firing in helium at 800 deg C; Impregnating the graphite by first evacuating the pretreated material and then admitting an aqueous uranyl nitrate solution whose concentration is etermined by the final uranium content desired in the raphite; Drying the impregnated graphite slowly under quilibrium conditions; and Conversion of the uranyl itrate to U/sub 3/O/sub 8/ by firing in helium at 800 deg C. By this process fuel rod elements have been made which contain as much as 19% U/sub 3/O/sub 8/ distributed uniformly throughout the graphite. The considerations leading to the choice of this process are discussed in this report, together with the alternate procedures which were investigated. (auth)

It has been suggested in the past that special numbers of neutrons or protons in the nucleus form a particularly stable configuration.{sup1} The complete evidence for this has never been summarized, nor is it generally recognized how convincing this evidence is. That 20 neutrons or protons (Ca{sup40}) form a closed shell is predicted by the Hartree model. A number of calculations support this fact.{sup2} These considerations will not be repeated here. In this paper, the experimental facts indicating a particular stability of shells of 50 and 82 protons and of 50, 82, and 126 neutrons will be listed.

This is a monthly progress report on the following programs: (1) 184-inch Cyclotron; (2) 60-inch Cyclotron; (3) Synchrotron; (4) Linear Accelerator; (5) Experimental Physics; (6) Theoretical Physics; (7) Isotope Research; (8) Chemistry; (9) Medical Physics; and (10) Health Physics and Chemistry.