The feasibility of improving swelling resistance in metallic uranium by increasing the dislocation density is under investigation. Increasing the density of dislocations is expected to increase the number of sites at which fission product gas atoms are "pinned," increase the number of gas bubble nuclei, and increase mechanical strength. Dislocations are introduced by a treatment which involves deformation of metastable beta or gamma phase in uranium-rich alloys, followed by transformation. Activity has been concerned primarily with selection of uraniurnbase alloys for initial evaluation, procurement of materials, installation of specialized equipment, and development of techniques. A number of small ingots were produced, and screening tests were carried out on several analyses. These preliminary experiments were designed to show the deformation characteristics of the alloys in the metastable state as a function of rolling temperature and time. Initial results on gamma-stabilized binary alloys containing 2, 3.5, 5, and 7 wt. % Mo showed that large reductions are possible in 5 and 7 wt. % Mo alloys at450 deg C. The more dilute alloys are relatively difficult to roll, although small reductions were achieved. Aging experiments on deformed and undeformed 5 wt. % Mo alloys indicate that deformation accelerates the aging process and …

The net multiplication effect of beryllium oxide, which is due to the (n,2n) reaction, was calculated using an essentially exact calculation of the neutron spectrum as a function of energy. The upper limit of the (n,2n) cross section curve gives the unpoisoned value epsilon /sup +/ = 1.047 and the lower limit gives epsilon /sup -/ = 1,027. The behavior of the Li/sup 6/poisoned fast multiplication effect as a function of the number of collisions was studied for both beryllium and beryllium oxide. (auth)

"Abstract: Data on analog magnetic tape characteristics are presented along with results from conventional and modulator playback system operational tests. Theoretical considerations imply that the modulator head should be loss sensitive to short term variations in record and playback tape speed. It is also pointed out that although a tape recorder operating at 7.5 in./sec has only 12 kcs bandwidth for sinusoidal wave forms. the record and play-back amplifiers for pulse recording can operate with other bandwidths. These amplifiers must be capable of passing a square wave with a frequency of 1.5 kcs. A square wave of such frequency represents the condition of 350 microsecond pulses with a 700 microsecond period. (J.R.D)."

Data on analog magnetic tape charactcristics are presented along with results from conventional and modulator playback system operational tests. Theoretical considerations imply that the modulator head should be loss sensitive to short term variations in record and playback tape speed. It is also pointed out that although a tape recorder operating at 7.5 in./sec has only 12 kcs bandwidth for sinusoidal wave forms. the record and play-back amplifiers for pulse recording can operate with other bandwidths. These amplifiers must be capable of passing a square wave with a frequency of 1.5 kcs. A square wave of such frequency represents the condition of 350 microsecond pulses with a 700 microsecond period. (J.R.D)

The purpose of the test was to insure satisfactory operation of the turbine after overhaul of the turbine which was completed February 1, 1959. The operation of the turbine during this start-up was satisfactory.