The first part of this quarterly progress report details reactor theory and design, discussing the aircraft reactor experiment, experimental reactor engineering, reactor physics, and critical experiments. The second part of this report is not included. The third part of this quarterly progress report details materials research, discussing corrosion research, physical properties and heat-transfer research, metallurgy and ceramics, chemistry of high-temperature liquids, and radiation damage. The fourth part of this quarterly progress report details alternate systems, discussing a supercritical water reactor, circulating-moderator-coolant reactors. The fifth part of this quarterly progress report includes appendixes.

Two methods were developed for the determination of uranium metal in UF3 with other fluoride compounds. A simplified method of determination which has a relatively high degree of precision (coefficient of variation 2 per cent) is carried out by decomposing the hydride in an atmosphere of carbon dioxide and subsequently measuring the hydrogen over an aqueous solution of potassium hydroxide. The ignition of the hydride in an atmosphere of oxygen and volumetric measurement of the water at reduced pressures provide a more sensitive method of determination. The coefficient of variation of the latter procedure is 7 per cent. The yield of gas from the reaction of the hydride with ammonia and gaseous hydrogen chloride was found to be neither stoichiometric nor reproducible.

Technical report outlining the investigation of corrosion on MTR type fuel elements for the Shielding Reactor in filtered water. Report includes two basic types of protection: element pretreatment by either anodizing or alodizing, and solution control using nitric acid to maintain a pH of 5.5 to 6.5 or the addition of 60 ppm sodium chromate as an inhibitor. [From Abstract]

Technical report covering the technology of hot-pressed beryllium production and its rapid advancement toward the end of 1949. Part I is devoted to corrosion studies made on hot-pressed and vacuum cast extruded metal which was considered representative of production. Part II is concerned with the results of tests made on special cast and hot-pressed beryllium which contained added impurities. [From Introduction]

Technical report outlining the fabrication of twenty-five fuel assemblies and three shim-safety rod fuel sections for use in the Materials Resting Reactor Mock-Up Critical Experiments. Results show that two of the assemblies exceeded tolerance in a few of the key dimensions, but were considered acceptable and as a consequence, production was carried out with no rejects. [From Abstract]

Technical report focusing on the Homogeneous Reactor Experiment (HRE) construction, completed 60% as of August 15, 1951. Report also includes alternate systems studies and long range studies of the Homogeneous Reactor Experiment. Technical report is organized in three parts. [From Summary]