From summary: This report contains data collected during a geochemical survey for uranium in the Torrington National Topographic Map Series (NTMS) quadrangle of east-central Wyoming (Fig. 1) by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

Report of uranium findings from a reconnaissance of the Gallup NTMS quadrangle through water, sediment, and water samples collected from streams, springs, and wells.

From summary: This report contains data collected during a geochemical survey for uranium in the Billings National Topographic Map Series (NTMS) quadrangle of south-central Montana (Fig. 1) by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

This report provides uranium and other elemental data resulting from the Hydrogeochemical and Stream Sediment Reconnaissance (HSSR) of the Dillon quadrangle, Montana/Idaho.

By use of small magnetic probes inserted into the discharge, the magnetic field distributions in the interior of a high-power pinched discharge have been measured as a function of time. From these data the current distributions can be deduced. By applying a static pressure calculation, in the cases when the radical pinch accelerations are small, the plasma pressure nkT in the pinch has been determined, with superimposed axial magnetic fields, and for stable and unstable configurations.

The production yields of hydrazine by various ionization methods are compared. The maximum value of M/N (number of molecules reacting per ion pairs) for electric discharge was 0.25 and for beta particles on liquid ammonia, M/N = 0.31. A 1-Mev reactor could produce 1.6 kg of hydrazine per hour if M/N = 0.04 as determined by alpha particles on liquid ammonia. About 300 ev of energy were needed to form a hydrazine molecule. (C.J.G.)

The results of a series of neutron diffusion calculations relating to an untamped Orally sphere are presented in detail in this report. The three-velocity neutron transport theory was taken as the basis for the analytical work preceding the computations. This particular theory, also known as the transport approximation, is defined in LA-1271 and known to be quite accurate for assemblies primarily involving materials of large atomic weight. For a sphere of uniform density and atomic composition the transport theory has another advantage. It can readily be formulated in terms of simultaneous integral equations (in our case three), relatively simple in form, involving the collision densities [formula] and a set of parameter values describing the materials. Nb(r) is , as indicated, a function of the radial distance [formula] and the velocity index g, g - 1, 2, 3. The parameters, fifteen in number for the three-velocity theory, are comprised of the velocities, the inverse mean free paths, and the transfer coefficients.

Certain types of neutron diffusion calculations were considerably simplified when the Serber.Wilson Method was introduced about eight years ago. This method, semi-empirical In nature and named after its co-discoverers, was first formulated for the one-velocity isotropic theory and applied to spherical geometries. Within these limits it has in general proved to be a fairly accurate method. If restricted source-free case it has, in addition, turned out to be quite manageable both analytically and numerically.

This technical report summarizes the apparent hematological changes in 10 individuals, exposed to total-body gamma radiation in near tolerance amounts, over a period of four and one-half years. Two control groups, in addition to the exposed group, were used for comparative purposes. Control group I received essentially no gamma or beta radiations. Control group II received exposures at least a factor of 10 below those of the exposed group. The average total leukocyte count, absolute neutrophil value, and absolute lymphocyte value, were determined for each individual and for all groups. Analysis of data indicates a significant depression of the absolute lymphocyte value of the exposed group as compared with those of the control groups.

Abstract: "This report describes work done to improve the casting characteristics of methyl methacrylete resin under CMR-6-18 authorization. The experimental program was initiated with the objectives of decreasing casting time, bubble formation and shrinkage. It has been found that by use of a common solvent for monomer and polymer concentration in monomer can be attained greater than any previously reported in preparation of a methacrylate casting resign. Incorporation of this greater amount of polymer has produced the desired effects. A bibliography of relevant literature is included to which reference is made in the text."

Notes Based on a set of five lectures given by R. Serber during the first two weeks of April 1943, as an "indoctrination course" in connection with the starting of the Los Alamos project.

Part 1. The neutron fission cross section of U237 has been measured in a thermal neutron spectrum and in a somewhat degraded fission spectrum. The fission cross section for thermal neutrons is found to be <2 barns; the ratio of the fission cross section of U237 to that of U235 in the degraded fission spectrum is found to be 0.476 +- 15% which corresponds to [formula] in this spectrum equal to 0.66 +- 0.10 barns. Part 2. The average neutron fission cross section of U237 has been measured in a neutron energy range extending from approximately 100 ev to fission spectrum. the average fission cross section in this spectrum is found to be 0.70 +- 0.07 barns. Part 3. The low thermal fission cross section for U237 (<2 barns) indicated that the excitation function for fission probably shows an effective threshold. If the excitation function is like all other heavy element (Z > 90) neutron fission excitation functions, it will exhibit a region of approximate constancy starting at a neutron energy of 0.5 to 1 Mev above its effective threshold and extending to a neutron energy in the neighborhood of 5.5 Mev. A hypothetical excitation function for neutron fission of …

From introduction: This report describes work done in the Durango National Topographic Map Series (NTMS) quadrangle, Colorado, by the Los Alamos Scientific Laboratory (LASL) as part of the nationwide Hydrogeochemical and Stream Sediment Reconnaissance (HSSR).

Uranium can be rolled from cast metal or forged ingot to sheet satisfactory for cupping, deep drawing, and similar fabrication procedures by a combination of hot breakdown in the neighborhood of 600 deg C and warm finishing at 225 to 325 deg C. Sheet may also be obtained by hot rolling alone and by warm rolling alone. However, it is difficult to secure a uniform, controlled grain size by hot rolling only and warm rolling is time consuming because of the limited reduction per pass obtainable. The combination of hot and warm rolling afforded best and most practical method to secure good quality sheet in the quantity required. The percent reduction by hot working does not appear to be critical, but at least 60% warm reduction is desirable to obtain complete and controlled grain size by recrystallization with high ductility and strength properties. Except for research investigation, rolling of uranium below 225 deg C is not recommended. In the temperature range considered (below 225 deg C), reduction is difficult and must be limited to one to two percent if edge cracking is to be avoided. Hot rolling of unplated uranium from the as-cast or as-forged surface is recommended, using a …

Abstract: This document is a survey analysis of soil samples from Los Alamos, Pueblo, Bayo, and Mortandad canyons to determine the presence and activities of radioactive contaminants. Also included are the results of analyses of a few samples of grass and of surface water. This survey covers the period from spring 1953 to spring 1955.

A method of numerical solution is developed for calculating the Lapre coolant pressure drop and power output with variable coolant inlet pressure, flow rate, and reactor solution temperature. The results of a series of calculations are presented that show excessive pressure drops and sonic exit flow as the flow rate is increased and the inlet pressure is decreased. Both supercritical and subcritical coolant flow regions are investigated. Reactor power is shown to be strongly dependent on the solution temperature in the region of 70O-75O degree F. At the design flow of 12 gal/min, excessive coolant pressure drops are encountered at inlet pressures of 2000 lb/in. and below.

A method is presented for determining heat transfer rates and thermal stresses from the gamma-ray energy absorption of nuclear reactor shells for plane, cylindrical, and spherical geometries. Criteria for minimizing thermal stresses are developed, along with the corresponding external cooling rates necessary to minimize the thermal stress. Design charts are presented for rapid determination of approximate thermal stresses and heat transfer rates, along with a numerical example illustrating the use of the charts..

The coefficient of linear expansion of alpha plutonium has been determined for the range -180 to +100 degree C by the silicon-tube and dial-indicator method. The value of the expansion coefficient is reported as [formula]. Included are a detailed description of the apparatus and a discussion of the method.

The coefficient of linear expansion of alpha plutonium has been determined for the range -180 to +100 degree C by the silicon-tube and dial-indicator method. The value of the expansion coefficient is reported as [formula]. Included are a detailed description of the apparatus and a discussion of the method.

This report brings together an extensive accumulation of material replacement (danger coefficient) data for the various oralloy critical assemblies at Pajarito. Corresponding values of effective absorption and transport cross sections are derived. In certain favorable cases, inelastic scattering contributions to the effective absorption cross sections are estimated. Special applications of material replacement data include computation of the relationship between oralloy critical mass and concentration of a diluent and hydrogen isotopic analysis of heavy water and heavy polythene.

This report describes the optical analogue that contains an optical filtering system which controls the intensity of light according to the assumed initial distribution of activity over height and particle size and according to the assumed decay rate, a size control system which depends on the lateral dimensions of the cloud of debris and adjusts the size of the light beam accordingly, and a position control system which moves the beam to the correct position on the plate as determined by the wind structure and the time of fall of the particles.

The bibliography provided investigates the following sources: Chemical Abstracts 1947-1950., Metallurgical Abstracts Vols. 1-18., ASM Review of Metals Literature Vols. 1-6., J. Institute of Metals Vols. 78-80 (No. 7)., Physics Abstracts 1937-1950.

Radiochemically determined mass-yield curves are given for the fission of U235 and U236 by 14.7-Mev neutrons.

The effects of certain process variables on the production of uranium tetrafluoride from U3O8 on the 250 g. (uranium) scale, and smaller scales in a few cases, have been studied. It was found that the initial step (reduction of U3O8 to UO2 by hydrogen) is essentially complete in 15 minutes at 700 degree C. The rate of conversion was shown to be temperature dependent, the greatest increase in rate of conversion occurring in the vicinity of 500 degree C. In the conversion of UO2 to UF4 by hydrogen fluoride, the optimum temperature was found to be abut 600 degree C. For a reaction time of 5-1/2 hours, both higher and lower temperatures yielded less completely converted products. An increase in rate of conversion, both in reduction and hydro-fluorination, resulted when smaller quantities of material were used. Changes resulting from the present study and yielding an increased efficiency in the production process are described.