The following report supplements a previous report by E.R. Saunders and M. C. Carosella and a report by A. J. Gailey and E. O. Brimm based around the same subject. This report describes a number of tests in which leaching temperatures of 115 and 125 C were tried for the extractions of uranium from western ores.

Abstract: "The leakage of neutrons from a heterogenous pile with finite aides is calculated developing the method used in CP-992. The change in the fraction of neutrons absorbed by the moderator is obtained using the results of the calculation of the leakage."

Abstract. Chemical analytical studies of graphite raw materials have revealed new sources of petroleum cokes and pitches of greater purity than those previously used in the manufacture of project graphite. The use of these raw materials of exceptional purity has resulted in an improvement in k of the order of one per cent as compared with the AGOT-AGNT graphite typical of the previous production. A study of the graphitizing process has shown that no dangerous impurities are introduced in the graphite in manufacture; rather, the process actually purifies. furthermore, impurities are distributed homogeneously within the furnace charge; thus the AGOT-AGNT distinction is no longer necessary. A comparison of the methods of graphite testing has demonstrated excellent correlations between chemical analytical data, the results of the function test at Argonne, and the sigma pile experiments. It may therefore be inferred that chemical testing should be an adequate control of the graphite purity. Methods are described for the analysis of ash, B, V, TI, FE, and Ca in petroleum coke, pitch, and graphite.

Abstract: Measurements are reported of the solubility of uranyl sulfate in water at several temperatures, of the density of uranyl sulfate solutions as a function of concentration, of the variation of density of uranyl sulfate solutions of three different concentrations over a temperature range from 0[degree]C. to about 93[degree]C., and of the pH of uranyl sulfate solutions as a function of concentration as well as of temperature. The pH measurements were taken on uranyl sulfate samples prepared in several different ways and some conclusions are drawn as to the purity of theses samples.

Purpose: "The purpose of the following experiments was to obtain data on the selective extraction of uranium over vanadiur from samples of vanadium ores by leaching with sodium carbonate or sodium bicarbonate solutions, with the object of establishing the time, temperature, and concentration conditions necessary for satisfactory extractions."

This report was written to replace the directions submitted on April 12, 1943 with improved directions for the preparation of chemical solution X(OC₂H₅)₅.

The following memorandum discusses experiments and methods to recover uranium from Colorado-Utah sandstone and leaving the vanadium in the tails, improving filterability.

From abstract: "Frequently it has been desirable to prepare pure anhydrous metal fluorides. Several general methods have proved satisfactory depending on the type of fluoride to be prepared."

This technical report consists of day by day experimental data reported in Engineer's Log book, Electro-Chemistry Department, supporting Report No. EC-11 dated November 15, 1944, by W. L. Grube, Research Laboratories Division, General Motors Corporation.

From abstract: "Using the method of induced radioactivity, the capture cross section of Pb[^]208 for C neutrons is found to be .00045 ± .00015 x 10[^]-24 cm[^]2. This is definitely lower than the value of .001 x 10[^]-24 reported by Maurer and Ramm."

Technical report: The apparatus for the low pressure combustion method of determining carbon in iron and steel has be redesigned to increase the speed of manipulation. It has been tested by running several thousand determinations and found to yield results in good agreement with Wooten's form of the apparatus. A detailed description of the equipment and its manipulation is given together with an account of experimental studies on the method. Results are also shown for the carbon content of copper.

Technical report listing the errata for pages 2, 4, 5, 6, 7, and 8 for report CC-918.

From introduction: The general distribution of known deposits of vanadium-bearing sandstone, which also contain some uranium and radium, is shown in figure 1 1/ and Exhibit A, plate 53. 2/ During 1939-41 the Geological Survey made detailed geological studies of these deposits in the Uravan district, Montrose County, Colorado, as well as preliminary examinations in other parts of the Colorado Plateau vanadium region. In 1942 detailed geological studies were made o the deposits in the Egnar-Slick Rock district, San Miguel Co., Colo.; 3/ the Carrizo Moungains district, Navajo Indian Reservation, Arizona and New Mexico; 4/ the Placerville district, San Miguel County, Colo. 5/ and the Monticello district, San Juan Co., Utah. 6/ Since May 3, 1943, the Gelogical Survey has guided the Bureau of Mines program of prospecting these deposits in parts of Colorado and Utah.

Abstract: "An accurate calculation is given for the quantity which corresponds to the diffusion length in the theory of the pile. The procedure is to establish a relationship between the diffusion length and the change in thermal utilization from a pile with infinite sides to one with sides of a finite length. The calculation of this change in the thermal utilization is then carried through. Approximation to the answer and numerically exact calculations are given in the report. The results show that for radif very near the optimum values the exact diffusion length is slightly larger than the one obtained from the usual formula...However, over most of the range of radii the exact diffusion length is smaller than the approximate one."

The following report discusses measurements for slow and fast neutrons from cadmium coated ionization chambers.

A report on the SOM-vanadium occurrences of the Huerfano Park District.

Summary: "Water containing 1.8% D2O was distributed between the two liquid phases formed with triethylamine at 20 and 35 C. The triethylamine was removed from each phase by aseotropic distillation with benzene before analyzing the water by determining its density with a quartz float. The ratios of the concentrations of the D2O in the water layer to that in the amino layer were 1.007 and 1.004 at 20 and 35, respectfully. The differences from unity are about the same as the errors of analysis."

Abstract: "Samples of dust are collected from the atmosphere with a Mine Safety Appliance Co. electrostatic precipitator and analyzed for uranium by means of a dropping mercury electrode apparatus. Two to three micrograms of uranium can be detected in a cell solution volume of 1 ml. Iron, nickel and chromium present in shop dusts do not interfere. Copper may interfere if present in excess but may be removed by a sulfide precipitation. Directions for preparation of cell solution and operation of the Polarograph are given. The polarographic method described may be used for determination of uranium in samples other than atmospheric dusts."

This report follows research done at the Purdue Research Foundation and Department of Chemistry on fluorocarbons done by the Office of Scientific Research and Development.

A report discussing a possible new volatile compound of uranium, its probable properties, and attempts to synthesize it. Though the possible new compound was not successfully synthesized, the author provides suggestions for future work.

From abstract: "This paper gives a method for determining Uranium using sodium cresotate as a colorimetric reagent. A precision is obtained of better than 2%. In carrying out analyses for Uranium in corrosion products by existing methods such as ignition to the oxide, silver reductor, or titration with ceric sulfate, it became apparent that a rapid, fairly accurate method for determining uranyl ion would be of great value. Such a method is described in this paper. The most logical color to use is that given by the ferrocyanide complex, but upon studying this, it proved to be unsatisfactory. Sodium salycilate also gives a color which has been used with some success, but its color appears to fade and is not very sensitive. A similar compound, sodium cresotate, was found to give an orange-red color and is the reagent used in the method to be described."

Abstract. The precipitation of Pa233 with MnO2 from a solution of thorium nitrate has been studied in some detail and seems quite satisfactory up to 36 gm Th(HO3)4 4H2O per 100 cc solution. The concentration of Pa233 with respect to the manganese dioxide carrier and the thorium precipitated with the carrier appears to be accomplished quite well by either a series of MnO2 cycles or thorium iodate cycles. Volatility methods for both the separation of Pa233 from the original thorium and for its separation from MnO2 are now under investigation. It has been decided that thorium carbonate will the the thorium compound used in the pile at Site X.

"In this report are presented three figures which show how the relative activities (expressed as percentages of total activity) of the individual fission elements (produced by neutron bombardment of uranyl nitrate) vary with cooling time."

The following report provides data taken from investigations on radiation and the different biologic effects on it.