A report which deals with the Redox IA Column studies made in small-scale columns packed with 3/16-in. Fenske helices and using NH4NO3 salting agent.

Introduction: Static, total immersion corrosion tests were carried out at room temperatures with Carboloy grades 44-A, 78, 907, X-3119-A and X-3119-B in Redox process solutions (ANL, June 1, 1949 Flowsheet) 1AX, 1AF, and 1AS.

Abstract: "The critical mass both of an untamped and water-tamped sphere with parabolic radial variation of the intrinsic buckling is calculated by a perturbation method. The result is applied to finding the minimum critical mass of plutonium in water suspension with infinite water temper; the calculations show that the minimum critical mass at constant concentration may be reduced by an amount of the order of 7.6% when the concentration of plutonium is permitted to vary throughout the suspension."

Abstract: Mice of different ages ranging from 1.5 to 12 months have been exposed to gamma rays in an effort to determine the change in radiosensitivity with age. The dose necessary to cause 50% killing was determined for each age group and sex. No change in sensitivity with age was observed with either sex, although the experimental error in the case of the males was quite large. The females were found to be more resistant than the males.

The present report is concerned with the electronic relay which, upon the reaching of a pre-determined value of ionization current in the associated chamber, actuates the safety rod release mechanism. The are here proposed two independent suggestions: (1) An improved trip circuit of such sensitivity and stability as to allow it to be actuated by a signal directly from the chamber without the necessity of interposing intermediate amplifier stages. The value of chamber current at which tripping occurs is stable to +- 0.4%. (2) A triple-wound relay to prevent shut-downs of the pile which would otherwise be caused by development of defects in the safety circuits.

The resonance absorption of a lump is described in terms of three components. Calculations of resonance absorption are carried out using the model for the resonance spectrum of uranium recently derived; calculations are also made with variations of this model which involve local fluctuations in level strengths. For metal and oxide lumps the agreement with observation is satisfactory. For dilute mixtures, whose resonance activation was measured by Mitchell, computed values fall 20% to 30% above measured ones.

Abstract. Measurements were made to determine the effect of thermal cycling on heat transfer from slug to jack using a slug with a sand blasted surface. The value of the transfer coefficient h decreased from initial values ranging from 10 to [formula], to values and [formula] after 1700 cycles, and to a range of 0.15 to 0.45 [formula] after 3200 cycles. Comparisons are made with the results found for slugs with different surfaces.

Abstract. Irradiated Whiting graphite possesses a small negative or a positive Hall constant, depending upon the dosage. Annealing at 500 degrees C for 1 hour in helium results in a Hall constant which is large in magnitude and negative in sign. The properties of the annealed graphite are presumably close to those of the original unirradiated material. Unirradiated AGOT-K graphite has a large, negative Hall constant. A mechanism is suggested which accounts for the change in sign of the Hall constant as a result of neutron bombardment.

The following report describes the results from studies based on the toxicity and metabolism of radioactive substances derived from uranium fission. Rats and mice were administered radioactive sodium and reactions and changes were studied.

Report discussing equipment that can be used to perform chemical and mechanical operations involving radioactive materials safely. Illustrations of the equipment are provided.

Abstract: The distillation and residue extraction recovery procedures developed for the recovery of uranium from Kinney and diffusion pump oil, were applied to contaminated precipitron oil. The effectiveness and advisability of using the method, in whole or in part, is discussed, and various recommendations for processing this particular type of oil are presented. Additional contaminating substances present in this type of oil added to the complexity of the problem but a satisfactory recovery procedure was, nevertheless, successfully developed.

Abstract: "Tests have been developed for both the qualitative detection and quantitative determination of fluorine in chlorine. The qualitative test is made by passing the gas through manganous chloride. If the pink solid tubes brown there is greater than 0.5 percent of fluorine in the gas. The quantitative test is a modification of the Steiger and Marvin Test with oxidized titanium solution."

Abstract: "The definitions of the fundamental measures of calutron operation including enhancement, current ratio, and process efficiency are set forth with derivations of the relationships between them. An analysis of the plant process is carried out for both the tanks limited and the charge limited case. Equations are derived for plant X output and plant X utilization efficiency. Effective production is defined and the value of increment to a mass of product material in terms of effective production is determined. An equation giving the X concentration below which product material should be reprocessed is derived."

The following report briefly covers broad general features of the chemical studies to be used by the Atomic Energy Commission in considering future work on the chemical studies of phosphate rock and shale.

Summary: A method is presented for the precipitation of tuballoy, apparently as a tubanyl ammonium sulfite, from gunk solutions containing the contaminants encountered in the recovery cycle. The impurities are not precipitated under the conditions employed, and their amounts in the product are reduced to values which can be attributed to occlusion. The recovery of tuballoy on one precipitation ranges from 99.5% to 99.9%.

This report records analyses on the fluorescence procedure of uranyl salts.

Quarterly report discussing the progress made with various projects at Argonne National Laboratory during the period from January to March 1948.

"This work is a continuation of an investigation begun in January, 1945, on a laboratory study of various methods for the chlorination of TO3. The work carried out this month deals entirely with gas phase chlorination, the liquid phase chlorination of TO3 having been turned over to Miss Hubbard. Gas phase chlorination of TO3 by means of CCl4, S2Cl2, SOCl2, SO2Cl2, and Cl2 have been carried out under varying conditions in the several different types of reactors."

Abstract: Exceedingly pure uranium tetrachloride was prepared for use in determining the physical constants of the compound. Measurements were obtained of the melting point and boiling point at pressures ranging from the triple point pressure to atmospheric pressure. Calculations were made of the vapor pressure equation for the liquid, the heat of evaporation, molar boiling point elevation, the vapor pressure equation for the solid, and the critical temperature.

The following report discusses ohmic characteristics in resistors, including methods for determining the polarization characteristics of high megohm resistors that may determine the suitability of these resistors for spectrometric measurements.

Abstract: A procedure for the preparation of the nitrides and carbides of several metals and the preparation of the refractory bodies from them is described. The investigation shows that reasonably strong and dense bodies can be prepared from these materials as well as from UO₂. Evidence showing the tendency toward instability at high temperatures of Be₃N₂, TaN, and ThN is presented. Evidence is also given indicating that the hexagonal structure reported by others for TaN is actually that for Ta₂N. A lattice for Th₂N₃ is proposed. The melting points of ThN, UN, and UC are determined to be 2630 ± 50°C,2650 ± 100°C, and 2590 ± 50°C respectively.

The following report was written to replace previous directions submitted in the February 6, 1943 report on the preparation of the solution X(OC₂H₅)₅.

Report discussing a general introduction to heavy element chemistry.

Abstract: "This report suggests using methyl acetate extraction of charge material as a means of determining the non-volatile residue. It is shown that the volatile constituents of charge material are all extremely soluble in methyl acetate whereas the non-volatile materials are quite insoluble. Percent NVH on several samples of charge material by this method are reported and discussed."