Abstract: The velocity of sound at the time of 100-ton shot at Trinity was measured to be 1116.1 ft/sec. Values of blast pressure computed from the excess velocity are given, but are not considered as reliable.

From Introduction: "Thrust augmentation of an axial-flow-type turbojet engine by burning fuel in the tail pipe is discussed in references 1 to 3. Thrust augmentation of the same turbojet engine by water injection at the compressor inlet is reported in reference 4."

Technical report. Areas covered are properties of uranium halides, properties of uranium nitrides, and hydride formation at high pressure.

The following report covers the results of a general program that was conducted at the Oak Ridge National Laboratory to investigate the effects on plastic materials of exposure to radiation in the pile. In the investigation, several plastics were irradiated, and on removal from the pile, their rates of decay were determined by measurement of gamma activity in an ionization chamber.

"This report is the second phase of a broad program of study of the transient motions of helicopters in autorotative flight. The first phase (reference 1) dealt with the steady-state condition of autorotative vertical descent. This report is concerned with the the transition from the steady condition of hovering to the steady autorotative descent" (p. 1).

From Introduction: "In the present paper, the variation of effective gust velocity in convective-type clouds with altitude is investigated. Data obtained during 1941 and 1942 at altitudes up to 34,000 feet and data obtained more recently from the Thunderstorm Project (reference 5) at altitudes up to 26,000 feet are utilized for this purpose. Consideration is given in analyzing the results both to data for the range

Abstract. Methods for determination of both uranium and nickel in solutions of these metals are described. Alloys can be dissolved in nitric acid treated with citric acid to complex the uranium, and the nickel precipitated as nicked dimethylglyoxime. The uranium is reduced and titrated with standard ceric sulfate. These methods are for the determination of macro amounts of uranium and nickel with errors on the order of 0.1%.

Abstract: The erroneously high values for uranium content of salvage solutions as determined by the ether extraction-ascorbic acid procedure have been demonstrated to be due to the presence of colored organic materials in these solutions. Evaporation of such solutions to fumes of HC104 before extraction has been shown to be completely successful in preventing such interference while pretreatment with activated carbon is sufficiently successful for application in Control laboratories. Complete procedures for application of either protreatment and results of such application to composite salvage solutions received over a six-month period are included.

The following document describes the process of rare beryllium extrusion using graphite introductory cones with the purpose of finding a lubricant which would decrease excessive friction between the billet and prose parts.

Report issued by the U.S. Bureau of Mines on the sampling of chrome ore deposits in the western United States. Physical properties of the samples collected are presented. This report includes tables.

Abstract: A TEC regulator amplifier driving an Eaterline-Angus recording meter was used to record magnet current variations. Tests were made to determine magnet current variations. Tests were made to determine magnet current stability for currents from 500 amperes to 4000 amperes. Changes were necessary in both the TEC and GE regulators before currents below 2500 amperes could be regulated. Regulation to 0.025 percent for and hour was obtained for currents of 1000 to 4000 amperes with the TEC and GE regulators, and regulation to 0.05 percent for 500 ampere currents.

From cover page: This document has been assigned the above MDDC (Manhattan District Declassification) number, as given in the List of Declassified Documents issued semi-monthly by the Research Division, Manhattan District. In the case of Los Alapnos reports, LADC (Los Alamos Declassification) numbers are listed on the title page if known. This declassified document may differ materially from the original classified document by reason of deletions necessary to accomplish declassification. Hence, this copy of a declassified document does not constitute authority for declassification of classified copies of a similar document which may bear the same title and authors. Reference is made to District Circular Letter (Research Control 47-3) dated 31 October 1946, subject: "Instructions for Use of List of Declassified Documents," which outlines the procedure by means of which declassification of classified copies may be effected. Every effort has been made to reproduce with accuracy of detail the declassified document as certified for declassification. No corrections or changes have been made in the content of the document.

Report issued by the Bureau of Mines over briquetting of coal for development of more effective fuel. Materials, equipment, and processes are discussed. This report includes tables, illustrations, and photographs.

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.

The following report describes tests made for the purpose of determining the accuracy and permanency of various types of high resistance bleeders, and their resistance variation during use over a period of approximately six months.

Technical report on the studies that have been made on the composition and thermal decomposition of uranyl peroxide. The conditions of precipitation and drying have been found to have no appreciable effect on the composition of the compound, but do affect the physical appearance of the precipitate and the rate of thermal decomposition. The UO4 + 2H2O appears to be thermodynamically unstable with respect to UO3 at 25 degrees C and atmospheric pressure, although the rate of conversion is extremely slow. The UO4 + 2H2O is completely converted to UO3 on standing at 150 degrees C and atmospheric pressure for two weeks. Partially decomposed uranyl peroxide samples contain extra oxygen which is released on immersing the sample in water.

The following sources of contamination in cooling water of the P-9 plant are considered: (1) Fission recoils, (2) Corrosion of metal, (3) Recoil from aluminum, (4) Induced activity in the water. It is found that for a P-9 plant of 3.5 x 10(4) KW contamination of the river at "X" should not exceed the .1 r criterion unless coating failure occurs. Tables of the amount of coating failure permissible are given as a function of holdup time.

Bulletin discussing

Abstract: "A new method of determining 8-hydroxyquinoline by titration with electrolytucally-generated bromine has been developed. Results show good precision in the range 0.4 mg. to 1.6 mg. total 8-hydroxyquinoline, with 99% confidence limits of less than +/- 2%. An electronically-regulated constant current source, required by the method, is described. A new indicator system with high sensitivity to free bromine is discussed."

Report from the U.S. Bureau of Mines over the studies conducted on the Daisy mine and the Hillside mine in Hardin County, Illinois. Properties of the mines, and the types of mineral deposits found in each are presented. This report includes maps, and illustrations.

Abstract: "A method has been established for the estimation of volatile organic acids in aqueous process solutions containing UNH, nitric acid, ANN, sodium dichromate and small amounts of hexone. The practice is to distill a 400 ul or 500 ul sample in the presence of an excess of phosphoric acid and ferrous sulfate under a high vacuum; a special apparatus utilizing a receiver cooled with a dry ice-isopropanol mixture is employed. The distillate is taken up in isopropanol and then titrated potentiometrically with standard potassium hydroxide solution. Since nitric acid and organic acids are present, two end points are observed. The potassium hydroxide added between these end points is equivalent to the organic acids. In the titration, CO2 from the atmosphere or in the potassium hydroxide is a source of error. The former was avoided and correction was made for the latter."

Report issued by the Bureau of Mines on exploration by diamond drilling in Pend Oreille County. Results of the exploration are presented. This report includes tables, maps, illustrations, and photographs.

The change in the simple [formula] distribution of neutrons in a spherical lump of uranium caused by the distribution in velocities of thermal neutrons is calculated. If the calculated curve is fitted as well as possible by a simple [formula] curve, it is shown that the value of [formula] obtained in this way is a function of [formula], the radius of the sphere. For small radii the [formula] obtained in this manner will be as much as 25% greater than the [formula] corresponding to average velocity neutrons. The change in the thermal utilization caused by the distribution in velocities is discussed. The flux of neutrons into a sphere is calculated taking into account the velocity distribution and this is compared with the usual theory.

This report studies the effect of x irradiation on the maturation of the circulating reticulocytes, using samples of rabbit blood with and without phenylhydresine- or bleeding-induced anemia and comparing them to the blood of human subjects under similar circumstances.