An extension of the concepts advanced by Langmuir regarding the nature of the platinum catalyzed oxidation of hydrogen and the application of the resulting theory to the experimental data observed by Ranschoff and Spiewak for an HRE type recombiner indicates that their data are corrected by the dimensionless equation (see report) equally well, with a mean deviation of 3.8 percent. This expression is recommended as a basis for the design of catalytic recombiners. The catalytic combinations is pictured as consisting of two surface chemical mechanisms, one of which is oxygen diffusion controlled, the other hydrogen diffusion regulated, the mechanism "change-over" occurring at that point in the recombiner where the components are arriving at the catalyst surface by diffusion in stoichiometric proportions. The catalyst volume requirements for three two portions of the bed are shown to be (see report). The hydrogen mole fraction at the mechanism "change-over" point is (see report). And the relationship between the two mass transfer coefficients is (see report). Methods for evaluating the necessary transport properties of the ternary system steam-hydrogen-oxygen for carrying out design calculations are summarized, and the new significant parameters are tabulated and plotted to facilitate these calculations. The question of non-uniform velocity profiles …

The conversion of UNH to UF4 and UF6, utilizing moving-bed techniques, is being studied; sufficient progress has been made that an evaluation of the process is warranted. The procedures under study, the Fluorox Process, have three major advantages: (1) substitution of HF for high-cost fluorine, (2) considerable reduction in HF requirements, and (3) marked reduction in plant-size and mechanical complexity.

The hydrogen evolution method for the determination of uranium trifluoride which was developed by Manning, Miller and Rowan has been used for the determination of trivalent uranium in this laboratory for the past three years. The method has been applied to many different sample types supposedly pure UF3, mixtures of UF3 and UF4 and the large variety of mixtures of fluoride salts that have been investigated as possible nuclear fuels. These mixtures contained alkali metal, beryllium and zirconium fluorides. Several modifications have been made that have substantially improved the performance and ease of operation of the method. These improvements include the use of (1) an inexpensive, long-lasting source of pure carbon dioxide, (2) vacuum to assist in purging the system of gases that are insoluble in potassium hydroxide solution, (3) deaerated acid that has an extremely low quantity of non-absorbable gases, (4) slower flow rates of purging gas, (5) a sampling technique to minimize contamination, and (6) more dilute absorber solution to reduce film error. It is the purpose of this report to show the effect of these modifications and the applicability of the method various sample types that contain uranium trifluoride.

All tissues included in this report were received from Dallas, Texas and were collected, ashed and analyzed according to the methods described in ORNL-CF-57-2-2. The average value of the concentration for each element in a tissue is the average of the concentrations in only those samples of the tissue which contained the element. For example, if, of 25 lives analyzed, only 10 contained lead, the average for lead in liver is the average of those 10 values. For those tissues in which an element does not appear in every sample, the lowest value is reported as less than the limit of sensitivity of the method for that element in that tissue. For the elements, lithium and rubidium, the ash was a composited ash sample for each particular tissue. As an example, in lieu of analyzing 20 individual aortas, only on composited aorta as was analyzed.

A study has been made of the radioactive nuclides present in the cooling water of the Low Intensity Test Reactor. Prominent nuclides which have been identified include Np239 and certain fission products. The experimental evidence points to the probability that there could be adequate U235 contamination on the fuel plates to quantitatively account for the fission products identified in the LITR cooling water. inasmuch as new aluminum does not contain uranium, it must be assumed that the contamination occurs during the fabrication of the fuel elements.

Increasing temperature in an aqueous liquid system results in a decrease in liquid density and an increase in vapor density. When level is measured by the differential pressure method, temperature increase results in a decrease in the effective span f the instrument and a shift in zero. When the instrument reference leg is uncompensated, both zero and span shifts occur with the effects being most pronounced at the high levels. When the reference leg is compensated, zero shifts are eliminated (instrument zero is at 100% level for this type installation). For control purposes at levels above 50% of full level, the compensated reference leg installation will give the best results. For measurement of levels below 50%, the uncompensated installation is best. As errors in level indications will be produced, in either type installation, by temperature, pressure and steam withdrawal (power) effects, the placement of taps should be such as to place the normal or control level in the region of 50% indicated level.

Analytical expressions were obtained for the time behavior of fuel concentrations and fuel-feed rates in single-region, spherical, UO3-ThO2-D2O reactors.

Results of four experiemental runs in the Fluorox fluidized bed reactor system are reported. The engineering feasibility of UF6 production from UF4 by use of dry air of O2, 2UF4 + O2 = UF6 + UO2F2, in an Inconel fluidized bed reactor at 800-850°C was demonstrated in two experimental tests in which greater than 90% of the theoretical amount of UF6 was collected or measured. Two runs made with crude UF4 (produced from unpurified mill concentrate) as the feed material, showed that UF6 could be produced at 700-725°C but corrosion on Inconel was prohibitive.

At the present time, plants in the 100-500Mv size range are more numerous and carry the greatest portion (over 50%) of the total steam-electric plant load in the U.S. utilities industry. The contribution of plants of over 1,000-Mv capacity is increasing more rapidly than any other size clarification and at present represents about 10% of the total capacity. By 1962 the TVA will have six plants with capacities of over 1,000-Mv. The largest steam-electric plant in the U.S. is the TVA plant at Kingston, Tenn., with a nameplate capacity of 1,440-Mv. Turbine-generator units are also following a trend of ever-increasing size. In present construction, the 150-200 Mv size range for units is the most common and represents the greatest contribution to capacity. Two units of 500-Mv nameplate rating each, the largest in the U.S., are on order by the TVA, and an 800 Mv unit is contemplated.

This memorandum presents a description of several additional miscellaneous HRT core maintenance tools, not in an earlier report (1). These tools were used in the removal of the cut up diffuser plates, probing the core wall, gauging the size of the holes, and other simple tasks. Function, design, and operation are described for the following items.

A program has been coded for the ORACLE which will solve, using Monte Carlo technique, the transport problem for monodirectional, monoenergetic gamma radiation incident at an angle Θ, upon an infinite laminated slab of finite thickness. Each of the laminations (or regions) is itself an infinite, homogeneous slab of finite thickness. The code is designed to give estimates of energy deposition, energy flux, tissue dose rate, reflected and transmitted energy current, and the angular and energy distribution of the reflected and transmitted energy current. All the answers except for energy deposition and reflected and transmitted energy current are optional.