A research program is being conducted to obtain experimental data in the irradiation of plutonium-enriched fuel to confirm a theoretical model for predicting isotopic composition and reactivity changes in plutonium-enriched, light-water-moderated reactors. All program efforts have been temporarily deferred except for those associated with the irradiation of the program fuel element in the VBWR. The program fuel element was exposed to a burnup of 465 MWD/T during the quarter which brings the total to 2334 MWD/T. On the basis of the computed isotopic composition, the burnup obtained was 1450 MWD/T.

Summary: The scope and intent of this report is to demonstrate the feasibility of a nuclear powered tanker for service in the United States Maritime Fleet.

Purex process which utilizes solvent extraction to separate and purify uranium and plutonium from each other and from fission products contained in irradiated uranium fuel elements.

The question has arisen of how the beam in A-12 as a long resonant cavity might effect the frequency of operation and the field distribution. This study is published to make available the calculation of the direct beam effect as an illustration of general methods of attacking perturbing effects in resonant cavities.

The following report describes data on the provided phase equilibrium systems that show the general nature of the diagrams and the compounds and solid solutions which occur.

Abstract: "Preliminary data have been taken to evaluate X-ray absorption at the L III edge of uranium as a method of detection of uranium in solution. Uranium concentrations in water from 150 ppm to 30,000 ppm have been investigated. The effect of copper as a typical contaminant in the range of 737 ppm of copper to 36,850 ppm of copper has been investigated for a representative uranium solution. Instrumentation has been constantly improved and suggestions for further improvements in amplifying and counting equipment are included. Comparison of experimental data with theory indicates that the derived equations are adequate."

Summary of progress on various research projects conducted during January, 1952.

Abstract: Mice of different ages ranging from 1.5 to 12 months have been exposed to gamma rays in an effort to determine the change in radiosensitivity with age. The dose necessary to cause 50% killing was determined for each age group and sex. No change in sensitivity with age was observed with either sex, although the experimental error in the case of the males was quite large. The females were found to be more resistant than the males.