Technical report with short reports from the (1) Physics Section I; (2) Physics Section II ; and (3) Physics Section III.

Abstract. Measurements were made to determine the effect of thermal cycling on heat transfer from slug to jack using a slug with a sand blasted surface. The value of the transfer coefficient h decreased from initial values ranging from 10 to [formula], to values and [formula] after 1700 cycles, and to a range of 0.15 to 0.45 [formula] after 3200 cycles. Comparisons are made with the results found for slugs with different surfaces.

"This work is a continuation of an investigation begun in January, 1945, on a laboratory study of various methods for the chlorination of TO3. The work carried out this month deals entirely with gas phase chlorination, the liquid phase chlorination of TO3 having been turned over to Miss Hubbard. Gas phase chlorination of TO3 by means of CCl4, S2Cl2, SOCl2, SO2Cl2, and Cl2 have been carried out under varying conditions in the several different types of reactors."

"In an effort to prolong the life of certain equipment, an investigation has been made of the applicability of several high temperature ceramic coatings prepared by the National Bureau of Standards Laboratories."

Summary. The effect of the conduction electrons on the stopping power of metals has been considered from two essentially different points of view. No numerical calculations have been carried out, because we have found no completely satisfactory was of computing Z'e, the effective charge on the moving ion. A rather crude estimate made on the basis of the Thomas-Fermi atomic model indicates that Z'2/E is roughly constant. Using this relation one finds that the stopping power of the conduction electrons is of the same order of magnitude as the stopping power due to bound electron excitation, and is important for the greater part of the range of the particle.