Technical report outlining various experiments that took place in the Oak Ridge Area Critical Mass Laboratory until August 31, 1950. Experiments took place in categories of critical experiments, experimental engineering, heat transfer, radiation damage, nuclear measurements, reactor physics, ARE reactor design, circulating fuel reactors, and circulating moderator reactors. [From Summary]

Technical report surveying radio-chemical analyses by ORNL's Analytical Chemistry Division and Health-Physics Division of large volumes of rainwater for plutonium, uranium, and fission products. Overall, carrying efficiencies for Al(OH)3 scavenging of rainwater were determined for these elements, as well as for Pu and U. [From Abstract, Introduction]

Technical report outlining the physical operability of 30% tributyl phosphate in a hydrocarbon dilutent for the extraction of uranium from more feed slurries. Operability had been satisfactorily demonstrated in jet mixing columns at the pilot plant of the Mallinckrodt Chemical Works. [From Abstract]

Technical report issued as one of a series of reports concerned with corrosion studies for the Materials Resting Reactor, created to both determine the effect of various practices for fuel plate fabrication on corrosion resistance and to determine the extent of penetration of the fuel plates by localized corrosion attack. [From Introduction]

From abstract: "Neutron-irradiated uranium was electromagnetically separated to provide enrichment of the isotope of mass 236. The final isotopic abundance of U 236 was determined to be 95% in 1800 milligrams of uranium. Useful by-products of the program were 22 grams of 25% U 236 and 1100 grams of 99.7% U 235. These enriched materials have been made available for use on Atomic Energy Commission projects. Possible application of this separation process to recovery of the fuel from the MTR reactor is described."

From abstract: "Neutron-irradiated uranium was electromagnetically separated to provide enrichment of the isotope of mass 236. The final isotopic abundance of U 236 was determined to be 95% in 1800 milligrams of uranium. Useful by-products of the program were 22 grams of 25% U 236 and 1100 grams of 99.7% U 235. These enriched materials have been made available for use on Atomic Energy Commission projects. Possible application of this separation process to recovery of the fuel from the MTR reactor is described."

Technical report containing a comprehensive study of the physical metallurgy of thorium and some of its alloys containing additions of Be, Si, Zr, Ti, Al, Nb, Cr, Mn, and Ce. Melting range, fabricating characteristics, and tensile properties were studied. [From Abstract]

Technical report detailing kinetic equations that have been developed for a boiling-type reactor and inherent reactor stability studies that have been made on the basis of these equations. Presents features of the proposed reactor, comparisons of circulating types, investigations of bubble-rise velocities, effects of transient conditions of vapor mass in steam chest, and bubble time delay functions yield favorable results. [From Abstract]

From abstract: "The rate of hydrolysis of TBP and the effect of the hydrolysis products in the Purex Process have been studied. Hydrolytic conditions may be encountered in the process which would lead to formation of dibutyl phosphoric acid, causing significant losses of tetravalent plutonium in stripping. This situation may be easily alleviated by reducing and stripping the plutonium in the trivalent state."

Technical report investigating the corrosion resistance of thorium and thorium alloys containing from 2 to 6% chromium, columbinium (niobium), titanium, zirconium and titanium-zirconium in distilled water at 95ºC. The true effects of the various alloy additions could not be determined because of the more marked effect of cold working. [From Abstract]

From introduction: "The ORNL-ANP liquid-to-liquid heat exchanger design and development effort has been based on an exceptionally high performance matrix of closely-spaced small diameter tubes that permits practically pure counter-flow operation. In the course of full-scale aircraft power plant design work a number of charts for this type of heat exchanger has been prepared. These charts were intended in part to show the effects of the various parameters in a readily understandable form, and in part to simplify and to reduce markedly the chore of making detailed design calculations. These charts have proved so helpful it seemed very worthwhile to assemble them into a report along with brief explanations and sample calculations."

From introduction: "This report covers work performed in the Solid State Division for the quarter ending May 10, 1952." Topics covered include radiation metallurgy, engineering properties, solid state reactions, crystal physics, and special projects.

Results of tracer studies suggest that, in tributyl phosphate extraction processes designed to recover and purify fissionable material, minimum ruthenium extraction should be obtained from feeds at least 2 M in nitric acid or at least 1 M acid-deficient. Ruthenium decontamination was decreased by preheating the feed and increased by pretreatment with reducing agents. A pretreatment using 0.06 M ferrous ion and 0.5 M urea with 1 hr simmering at 85°C should increase ruthenium decontamination about 10-fold in the 25 process. If other process considerations dictate the use of a low-acid feed, decontamination from ruthenium may be improved by using 3 M nitric acid as the scrubbing solution. Apparently, the scrubbing process is quite time-dependent; a solvent holdup time of about 15 min may be needed in the scrub section for maximum decontamination.

An evaluation of the relative health hazards of radioisotopes produced in nuclear reactors is reported. The most important hazards were indicated to be I131, the Sr90 - Y90 chain, the Ce144 -Pr144 chain, Sr 89, the Ba140-La40 chain, Y91, the Zr95-Nb95 chain, Pr143, La140 , and Pa233. The most critical body organs affected by air-borne contamination are the thyroid gland, the bone marrow, the lungs, and the gastrointestinal tract. Where possible, continuous daily removal of gaseous and solid fission products from the reactor environment can be shown to permit very significant reductions in the total hazards. Homogeneous reactors, such as the Thermal Breeder Reactor and the Homogeneous Plutonium Producer Reactor, specifically studied in this report, are designed with daily removal cycles and may be considered potentially safer than heterogeneous reactors.

Progress report of the Oak Ridge National Laboratory Biology Division providing updates on various projects, experiments, and other work. This report includes a summary of scholarly output from the division and departmental activities in: cytology and genetics, microbial protection and recovery, mammalian recovery, mammalian genetics and development, pathology and physiology, microbiology, biochemistry, enzymology and photosynthesis, plant biochemistry, general physiology, and biophysics.

Experience in handling and purifying rubidium metal, prior to high-temperature corrosion testing, has been obtained. Some of the physical and chemical properties of this metal are listed. Distillation and filtration experiences are described, and the analysis of samples following such purification procedures are given. Stripping procedures following corrosion testing are discussed briefly. Results of preliminary corrosion experiments indicate that Inconel in a satisfactory container material for boiling rubidium at temperatures up to 1520°F.

The development of ionic methods for the determination of corrosive products in the highly radioactive Homogeneous Reactor (HR) fuels has been of major interest in the work of the Ionic Analyses Laboratory. Methods for the spectrophotometric determination of aluminum and for the polarographic determination of iron in HR fuels have been developed. The polarographic determination of molybdenum in uranyl sulfate solutions was studied. A polarographic method for the determination of zinc was developed. A fluorometric method for the determination of microgram amounts of fluoride was studied. Three organic reagents were investigated as precipitants for microgram quantities of zirconium in HR fuel. The automatic photometric titration technique was applied to the determination of thorium and of sulfate. A method was developed for the ion-exchange separation and potentiometric titration of cobalt. The ultraviolet absorption spectra of technetium and rhenium were studied.

Calculated data and graphs describing the effects of batch thermal-neutron irradiation of thorium, the usual method of operation of heterogeneous reactors, are presented. The buildup and decay of U233, Pa233, other heavy isotopes, and fission products are considered on the basis of best available cross-section and fission-yield data. The effects of these irradiation products on the Thorex chemical separation process are indicated briefly.

Report issued by the Oak Ridge National Laboratory discussing semiannual progress made by the Solid State Division during 1956. Descriptions of progress and studies made are presented. This report includes tables, illustrations, and photographs.

From introduction: "The purpose of the report is to set forth the development philosophy, objectives and expected results of the AEC-GE Nuclear Superheat Project."