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.

Abstract: Since the viscosity-temperature relationships of fluorocarbons are somewhat unusual, when compared to hydrocarbons, for example, it was decided to measure the viscosities, at several temperatures, of various fluorolube oils. The calculation of the viscosity of a blend of oils is at best an uncertain operation, varying considerably with the method used. A comparison of various methods was indicated, in order that reasonably accurate values might be assumed for theoretical composites. The densities were measured at corresponding temperatures for use in converting viscosities, and for their value, per se.

From introduction: "These data were taken on a 1/16th scale model of the magnet shown on sketch no. FS-2. The object of these measurements was to get information that would determine the final design of the full scale magnet. The one main point to be settled was whether a tapered or a cylindrical pole piece would give the largest value of Hρ for a given power input into the magnet (the cylindrical pole piece is shown in dotted lines in sketch FS-2)."

From abstract: "Comparison of the activity produced by fast neutrons on lead with other activations corroborates the assignment of the 3.2 hr. activity as Pb209, and the assignment of the reaction as capture of fast neutrons. Two different measurements show that the neutrons captured have energies greater than 100 KEV. This average capture cross section for primary neutrons from 7.5 MEV deuterons on a thick target of beryllium is measured as 10[^]-27 ca[^]2."

From introduction: "This article gives an account of the determination of the complete crystal structures of the normal orthophosphates of barium and strontium."

Description of a velocity analyzer (with diagrams) is given. It is a device for measuring the velocities of charged particles which comprises pairs of spaced electrodes, a collector for charged particles, and means for propelling charged particles in a direction so as to pass between the pairs of electrodes. The pairs of electrodes and the collector are so arranged to permit passage of the charged particles between them to the collector plate. Means are provided for applying an alternating substantially square wave potential of known frequency to the pairs of electrodes so that adjacent pairs are opposite in phase and so that one half-cycle of the wave appears as zero potential between the pairs of electrodes.

Abstract: The output signal of a linear accelerator may have a rise time of 1-2 x 10[minus]7 seconds. Therefore, the output of a pulse height selector operating on this signal has a variation of delay from the original signal of about this amount. In the instrument to be described in this technical report this difficulty is largely resolved.

From introduction: "The fact that tetravalent uranium either in the form of solutions of its salts or, in some cases, in the dry state is readily oxidized by gaseous oxygen, has been observed by various investigators. A quantitative study of this reaction appeared to be desirable as a means of learning more about the nature of the ionic species present in uranous solutions. It was also of potential value in determining the importance of autoxidation as an undesirable side reaction involved in the handling of uranous solutions, and, if necessary, in developing procedures for minimizing the reaction."