This quarterly progress report details ongoing work at the Oak Ridge National Laboratory as part of the Aircraft Nuclear Propulsion Project. Topics of discussion include reactor theory and design, shielding research, materials research, appendixes with information on ongoing analytical chemical studies.

From summary: "The hazards due to possible chemical explosion and detonation of the dissociation gases in homogeneous-reactor systems have been considered."

"This symposium is concerned with the basic aspects of radiation effects. When we turn to the genetic effects of radiation in mammals, there are so few aspects on which there is any information that the problem of sorting out the fundamental findings has hardly arisen. In this paper it will, therefore, be possible to survey most of what is known and pass on to a consideration of what is needed next. Since one of the purposes of this symposium is an interchange of views between investigators in different fields, an attempt will be made to avoid technical details. Among the practical needs in mammalian radiation genetics is a pressing one for more data on which to base estimates of the genetic hazards of radiation in man. The present paper will be concerned largely with this problem. Our own work is directed primarily in this direction, our objective being to uncover some of the basic facts in at least one mammal-the mouse. Before discussing the experimental work, however, it seems desirable to consider some of the general features of the genetic hazard of radiation."

From summary: "The influence of the structure of phosphate esters on the distribution coefficient of uranium between solutions of these esters in carbon tetrachloride and aqueous nitrate solutions has been studied. Esters of secondary alcohols showed higher distribution coefficients than primary alcohols. Phenyl esters extracted less uranium than alkyl esters, and the presence of other negative groups also resulted in less extraction. Compounds containing carbon to phosphorus bonds gave higher distribution coefficients than the corresponding esters, and the distribution coefficients increased with the number of such carbon to phosphorus bonds. Tributyl phosphine oxide (with three carbon to phosphorus bonds) showed high distribution coefficients with many salts, including uranyl nitrate, uranyl sulfate, uranyl chloride, thorium nitrate, plutonium (IV) nitrate and some of the fission products in nitrate solution. It is planned to study these and similar compounds further."

This quarterly progress details the ongoing work of the Protective Equipment Evaluation Program at the Oak Ridge National Laboratory. Topics discussed include aerosol generation, penetration studies, particle size measurement, and an appendix with analytical methods.

From introduction: "The tube arrangement covered in this report was proposed in June, 1950, as a means of halving the weight and volume required for the heat exchanger. Ideally, the pressure drop across this arrangement should be little more than that required to overcome the skin friction on the tube surfaces. If the pressure drop across the tube spacers and in the cross-flow regions can be kept low, this ideal can be approached. much of the test work covered in this report was devoted to this phase of the problem."

From abstract: "This report presents the laboratory development of the MTR-RaLa Process for the production of barium140 from Materials Testing Reactor assemblies." The laboratory studied four possible chemical schemes with the final process being chosen "on the basis of chemical yield and purity of product, ease of recovery of uranium235, simplicty of equipment, and overall time required for processing" (from introduction).

In certain phases uranium processing it is poss!ble for operating personnel to acquire internal deposits of uranium. This body burden can be acquired by injection, as in contamination of a wound, by ingestion, of by inhalation. In order to estimate internal exposures, some means of determining the location and extent of these internal deposits is essential.

Nitrate contained in raffinates from Canadian Blind River mills interferes seriously with thorium extraction by secondary amines. With primary amines, however, the effect is negligible and these compounds are the preferred process extractants.

The method of calculation of various quantities relating the temperature and the rate of heat removal of UO2 test elements is presented. Graphs of the appropriate quantities as a function of the rate of heat removal are included.

This memorandum summarizes the results of an analysis to determine the extent of displacement of the EOCR core due to blowdown in case of several postulated hot main gas coolant pipe failures. Results show that the core will be damaged for any hot pipe double-ended failure. Excepting the improbable case of no coolant flow existing proper to the break, the core will be damaged for any hot pipe fracture exposing a total flow area to the atmosphere equal to that of one pipe. Smaller breaks will probably be safe in this respect.

Many elements exhibit anisotropic scattering at energies of interest in reactor calculations. A method is presented for the calculation of transport cross sections including the observed anisotropy.

Preliminary measurements of the corrosion of titanium were made in 13 M HNO3-0.05 M fluoride using 0.1 M H3BO3 as a liquid and vapor phase complexing agent. Titanium Ax-55 was attacked at average rates of 0.58 and 0.33 mils/month in the liquid and vapor. In dissolver solutions containing 0.5 and 1.0 M titanium, all rates were less than 0.1 mils/month.

An improved heat sink for space vehicles was proposed in ORNL-CF-59-1-21. Subsequent work on the problem has indicated that there is a substantial probability of a puncture of such a radiator by meteors. To meet this problem a modified geometry has been evolved for which the probability of a meteor puncture should be reduced by a factor of at least 100 relative to the radiator of the original proposal at the expense of an increase in radiator weight of possibly 30%. This memorandum outlines the approach to the problem and a series of similar promising solutions.

An investigation of the materials for use in the water-moderated and cooled Aray Package Power Reactor (APPR) operating at about 500°F was made. The available literature was analyzed, and the results of the different investigators were compared and averaged. Twenty different materials, including stainless steels, nickel alloys, Stellites and others, were investigated from the point of view of physical properties, susceptibility to radiation damage, and corrosion resistance. Corrosion rates were established for all the materials under various conditions, such as irradiation, flow weld, stress, and various water conditions. Type-304 stainless steel was selected as the basic structural material. Operating conditions, to maintain minimum corrosion, were established also.

A fifth in-pile loop experiment, L-4-8, was completed. The loop operated in-pile for a total of 1637 hr, during which time the LITR energy output was 4377 Mwhr. The average fission power in the loop based o cesium analyses was 622 w when the LITR was at full power (3 Mw). Based on oxygen data, the generalized corrosion rate for the first 300 hr was 4.0 mpy; the rate for the remaining 1357 hr was 0.7 mpy. The nickel data gave parallel results. The corrosion of the type 347 stainless steel, Zircaloy-2, and Ti-55AX [unintelligible] exposed in the core and in in-line holders was generally consistent with that observed in previous in-pile loop experiments. Some differences with steel were attributed to the fact that this was the first loop containing steel specimens operated with 0.04 m H2SO4 present in the uranyl sulfate charge solution (0.17 m UO2SO4, 0.03 m CuSO4). Stress specimens, made from the alloys Zircaloy-2, type 17-4 PH stainless steel, and Ti-C-130-AM, were exposed in care, in-line, and pressurizer locations. Microscopic examination and average weight loss gave no indication of effects attributable to the stressed condition of the specimens.

Several potential hazards that have been recognized and anticipated in the design and fabrication of the pressure vessel in the Homogeneous Reactor Test are discussed. These hazards results from the high operating pressure and temperature of the reactor, the exposure of the reactor vessel material to potential embrittlement and other affects of fast-neutron irradiation, and the need for containment of corrosive flowing liquids. The steps taken in recognition of these hazards are also discussed. The applicability of present codes to the reactor vessel fabrication is considered. Additional fields are suggested where recommended practices developed by code writing bodies could assist in development-type reactor design and fabrication.

This quarterly progress report describes the ongoing research at the Metallurgy Division at the Oak Ridge National Laboratory. In particular, this report discusses the thorium research program, the slug problem, the preferred orientation and anisotropy in metals, fundamental studies of alloying, and the ANP program.

The purpose of this study was to investigate mathematically the concentration decrease due to particle deposition phenomena in highly concentrated monodispersed aerosols (mean particle size less than 1.0 mu) flowing through ventilation ducts. It was found that, from the standpoint of removal, the decrease in concentration due to deposition on duct walls was insignificant; but, when considering contamination on duct walls, the amount deposited, even though small when compared with the amount in the bulk stream, should not be overlooked.

A partial bibliography of reports on the Fluorox moving-bed for producing UO3, UF4, and UF6 is given.

An investigation of the materials for use in the water-moderated and cooled Aray Package Power Reactor (APPR) operating at about 500°F was made. The available literature was analyzed, and the results of the different investigators were compared and averaged. Twenty different materials, including stainless steels, nickel alloys, Stellites and others, were investigated from the point of view of physical properties, susceptibility to radiation damage, and corrosion resistance. Corrosion rates were established for all the materials under various conditions, such as irradiation, flow, weld, stress, and various water conditions. Type-304 stainless steel was selected as the basic structural material. Operating conditions, to maintain minimum corrosion, were established also.

The first step in a proposed processing method for recovery of uranium from graphite-uranium fuels consists of oxidation of the fuel by oxygen to volatilize the carbon. Residue ash from the combustion step can be treated in a variety of ways to recover and purify the uranium. The combustion step may be caried out by contacting the solid fuel in a fixed or moving bed with a stream of oxygen-bearing gas in a tubular or annular reactor. Oxidizing gas may be introduced to the reactor at several points up the reactor and there may be continuous or intermittent addition of fresh fuel and removal of residue ash.

The thermophysical properties of Armco iron such as thermal conductivity, electrical resistivity, and Seebeck coefficient have been extensively investigated and reviewed up to 1000 degrees C. Few investigations of such properties have been made on high purity iron. If such a study is made using the same apparatus to determine the properties of two purity levels of iron, then several significant intercomparisons can be made which add meaning to data on a single material. The systemic errors for a single apparatus are the same, therefore comparison of a property of two similar materials is more significant. A comparison of the property changes with temperature and purity can show the effects of impurities on the mechanisms contributing to a property and allows prediction of the properties of iron as a function of purity. For these reasons a study was initiated on the high-purity iron for comparison to Armco iron.

The experimental details, mathematical models, and typical data for a rapid comparative method for thermal conductivity measurements are presented. The method consists of measuring the temperature change of a small silver sphere after it is brought in contact with a small disk-shaped specimen which was initially at ta higher temperature. This temperature change was calibrated in the range of 50 to 400 degrees C by making measurements on samples of know thermal conductivity. The accuracy of this technique was shown to be between than +-10% with a reproducibility of at least +-2.5%. Using known transport mechanisms for heat conduction in solids and the temperature dependency of the electrical conductivity, a means to judiciously extrapolate thermal conductivity data obtained between 50 and 400 degree C to high temperature is presented.