The design of the present time of light mass spectrograph is similar to that of the isotron devised some time ago for isotope separation. The spectrograph will employ the time of flight principle only for the isotopic analysis of small samples.

A systematic set of thermodynamic data for most of the known compounds of plutonium is presented. From earlier data present, it is now possible to extend the tabulation of data for the compounds of plutonium to include PuF(4), PuF(5), and PuF(6).

Report discussing protactinium, including the element's history and the results of various experiments.

Report discussing the progress made on the Experimental Breeder Project during the period from March 1, 1949 to January 31, 1950.

Report discussing a procedure for the preparation of anhydrous vanadium trifluoride. From abstract: "By selecting proper operating conditions and equipment, a method of preparation was devised such that anhydrous vanadium trifluoride of high purity was produced reliably in five pound batches." The method of preparation involves manipulating the starting material, vanadium pentoxide.

Abstract: A tungsten tipped electrode has been used in the continuous casting arc furnace for a 25 minute period during which a 12 inch length of ingot was made. Thermocouple junctions within the mold wall have been improved to give mold zone temperature. A total of 10 iodide dissociation runs have been conducted using feed rates of .62-22.7 lbs ZrI₄ per hour with attendant conversion efficiencies of 97.7-16.4% and zirconium yields of 255-41.2 grams per hour. A curve expressing these data for an arbitrarily selected set of conditions is presented.