Abstract: "The critical mass both of an untamped and water-tamped sphere with parabolic radial variation of the intrinsic buckling is calculated by a perturbation method. The result is applied to finding the minimum critical mass of plutonium in water suspension with infinite water temper; the calculations show that the minimum critical mass at constant concentration may be reduced by an amount of the order of 7.6% when the concentration of plutonium is permitted to vary throughout the suspension."

Report describing the temperature in the Brookhaven concrete shield proposed for the X reactor. The report details the methods and equations used to find the values that determined that the effect of the gun barrel assembly in cooling the concrete is negligible.

Measurements were taken to provide experimental evidence for determining the feasibility of a proposed method for converting Pu240 to 241 by exposing shielded plutonium to selectively transmitted pile neutrons.

As part of an investigation of solvent stability, a direct analysis of recycled Uranium Recovery Plant solvent* has been made to determine the type, source, and properties of the impurities which have been generated in the solvent and are present in the solvent after it has been in use for some time. This work has been directed towards the separation and identification of the impurities by compound class, and the conclusions are set forth in this report. Another purpose of this report is to present the separation scheme employed, which will likely find similar application.

Eight zirconium and eight Zircaloy-2 process tube samples were irradiated in the "H" test loop, Tube 0961-H, so that the corrosion tendencies of the material might be evaluated when exposed to radiation. The samples were delivered to the Radio-metallurgy Building in January, 1955, and examined as requested by C. D. Wilson of the Pile Development Unit, Pile Technology Section.

Calcination of liquid radioactive wastes, the process of converting metal nitrates and sulfates to oxides by heat, is under development at Hanford as a means of reducing these liquids to a dry powder or solid which can be stored safely. Radiant-heat spray calcination, one of the methods under study, was first investigated at the Oak Ridge K-25 Plant (1) as a possible method of calcining uranyl nitrate to uranium trioxide. The process has also been under extensive development at the Pulp and Paper Research Institute of Canada (2) and is designated by them as the Atomized Suspension Technique.

Pressurized water nuclear reactors may be designed based upon either of two concepts: (1) pressure vessel, wherein the entire core is placed in a large, high strength fuel channels within a low pressure container. The Plutonium Recycle Test Reactor is a pressure tube type reactor. Selection of this basic type of pressurized water reactor depended to an appreciable extent upon the availability of suitable pressure tubing.