Three new americium activities (Am{sup 238}?, Am{sup 243}, and Am{sup 244?}, the latter two formed by n,{gamma} reactions) are described and some additional information is given on previously reported americium isotopes.

Neutron density at the end of the slug is increased appreciably and therefore the heat production in the end of the slug is also increased. The end result is increased heat flow into the cap with correspondingly higher temperatures. The combined results and conclusions of documents CP-1580, CP-1989, and CP-2871 afford a means of calculating the aluminum end cap temperatures with consideration being give to the above mentioned {open_quotes}Wilkins effect,{close_quotes} i.e., that the heat production near the end of a slug with an aluminum end cap is greater than the heat production at the middle (axially) of a slug. The maximum temperature in the aluminum end cap is calculated to be about 278{degrees}F. for the {open_quotes}G{close_quotes} Pile. This temperature occurs at the center of the maximum performance process tube.

The present liquid third safety is considered undesirable for the piles at their present power levels. Any increase in power level and graphite temperature makes the need for an alternative third safety increasingly imperative. The use of the third safety is envisioned under conditions where the supply of cooling water to an operating pile is interrupted and concurrently the safety rods full to enter the pile because of slight shifting of the top shield or larger shifting of the winches, relative to the pile proper. Under these conditions, undesirable properties of a liquid third safety are present and are discussed in this memorandum.

This report consists of an outline for a program for testing the air-supplied face masks currently being used as protection against P-10 atmospheres at HAPO. The test procedures which follow are intended to determine circumstances under which the mask ceases to offer protection to the wearer. To keep the scope of the test program to a minimum and also to facilitate interpretation of the findings in the light of P-10 atmospheres, the test conditions chosen were those which would be most unfavorable for the mask from a protection standpoint.

Research on polonium chemistry and physics is being continued on a reduced scale. Those problems which have direct bearing on the preparation of the metal and those which will lead to a better understanding of any phenomenon encountered are being continued. Data from the calorimetric measurements of polonium on Calorimeters 39 and 46 were treated by the method of least squares to give a grand mean half life of polonium equal to 138.3993 {+-} 0.0093 days (1-13). New apparatus has been constructed for the measurement of the vapor pressure of polonium and its compounds in the low and the high temperature ranges. Technical difficulties have delayed the actual collection of data (1-22). The constant current magnet to be used for the measurement of the Hall effect of polonium has been tested and found satisfactory. A device utilizing nuclear magnetic resonance absorption for determining field strength has been constructed on a preliminary basis (1-24). A total of 208 lines in the ultraviolet region between 3200 A and 1900 A have been measured with an error of less than {+-}0.02 A (1-28). Studies on the X-ray and spark spectra of polonium and its compounds have been conducted. A preliminary study by X-ray …

Pre-operation safety studies for the Homogeneous Reactor Experiment are discussed. (C.H.)

Report presenting an investigation of a model of the Bumblebee XPM missile to determine the causes of booster-fin failures for a range of Mach numbers and Reynolds numbers. The cause of fin failure was determined to be the launching shoes that caused the missiles to trim at increasingly negative angles of attack. Additional testing with wing spoilers and alternate booster fins was also conducted.

"An analysis was made at flight Mach number of 0.9 to estimate performance of nuclear-energy-powered turbojet engine and optimum engine operating conditions and to determine gross weight and load-carrying capacity of airplane powered by such an engine. The size of airplane required to carry disposable load of 20,000 pounds was found to vary from approximately 300,000 to 900,000 pounds depending on assumptions. For a reactor tube-wall mean temperature of 2500 degrees R, turbine-inlet temperature of 2000 degrees R, reactor-free-flow-area ratio of 0.33, reactor-shielding-material specific gravity of 6.0, shielding thickness of 3.0 feet, and altitude of 30,000 feet, the airplane gross weight required to carry a 20,000 payload is 545,000 pounds" (p. 1).

From Introduction: "Data are presented to show the effects of tail-pipe fuel-air ratio, altitude, and flight Mach number on tail-pipe-burner performance at rated engine speed and approximately constant turbine-outlet temperature. Operational characteristics of the tail-pipe burner and variable-area exhaust nozzle are also reported."

An equation for average heat transfer of a surface was derived when the boundary layer changed from laminar to turbulent. Influences on the heat transfer through a laminar boundary layer of Mach number, temperature ratio (gas temperature divided by wall temperature), and exponents of gas-property temperature relations were shown to be relatively small for air with Mach numbers less than 2 and temperature ratios between 1 and 4. Good agreement was obtained with experimental results from cylinders, an airfoil, and turbine blades.

The effect of fuel volatility on altitude starting limits of an axial-flow-compressor-type turbojet engine was investigated using fuels with Reid vapor pressures of 1.1 and 5.4 pounds per square inch. At flight Mach numbers from 0.40 to 0.85, the AN-F-58 fuel allowed consistent windmilling at altitudes 2000 to 8000 feet higher than was obtained with the 1.1-pound Reid vapor pressure fuel. At a flight Mach number of 0.25, ignition could not be established at any altitude with the lower-volatility fuel.

Memorandum presenting flight tests made on the Bell X-1 airplane with the 10-percent-thick wing and the 8-percent-thick tail to evaluate the effects of fixing the rudder and changing the inclination of the principal axes of inertia. The data were obtained during power-off glides at altitudes between 32,000 and 16,000 feet.

Analytical methods are presented for the determination of local values of outside and inside heat-transfer coefficients and effective gas temperatures by use of turbine-blade-temperature measurements. The methods are derived for a number of configurations that can be applied to typical cooled-turbine-blade shapes as well as to other types of heat-transfer apparatus.

Report presenting flight measurements of aerodynamic tail loads made on the Douglas D-558-II from which the variation with Mach number of the wing-fuselage aerodynamic center, static-longitudinal-stability parameter, the tail load per g, and the zero-lift wing-fuselage pitching-moment coefficient determined up to Mach number 0.87.

Report presenting results from a preliminary flight investigation on a swept-wing airplane of the lateral-control characteristics and wing-dropping tendency encountered at high Mach numbers. Measurements of aileron and rudder-control effectiveness are presented and used with estimated damping-in-roll characteristics and data from steady sideslips to approximate the variation of effective dihedral with Mach number.

Report presenting flight measurements of the dynamic longitudinal-stability characteristics of a 35 degree swept-wing airplane. The results indicated that a sharp reduction in damping at a Mach number of 0.92 with maximum damping occurred at Mach number of 0.88 and 0.94. Results regarding oscillation periods, damping coefficients, scatter, and number of cycles required for oscillations to damp to a certain amplitude are provided.

Report presenting the results of an investigation of a model of the Bumblebee XPM missile to determine the causes of booster-fin failures on full-scale missiles. Results indicated that failures of the fins were due to launching shoes which caused the missile to try at increasingly negative angles of attack as the Mach number increased.

"An analytic method for the design of automatic controls is developed that starts from certain arbitrary criterions on the behavior of the controlled system and gives those physically realizable equations that the control system can follow in order to realize this behavior. The criterions used are developed in the form of certain time integrals. General results are shown for systems of second order and of any number of degrees of freedom. Detailed examples for several cases in the control of a turbojet engine are presented" (p. 207).

The metabolism of C{sup 14} labeled glycolic acid by Scenedesmus has been studied using radiochromatographic techniques for the separation and identification of products. When the pH of the medium was 2.8, appreciable assimilation occurred. The products were identical to those observed in C{sup 14}O{sub 2} photosynthesis. A major reaction anaerobically in the dark resulted in incorporation of C{sup 14} in almost equal amounts in the glycine and serine reservoirs. When the algae were illuminated, a diminution in the amount of glycine was observed.

Report presenting results of a study regarding the critical masses and nuclear properties of plutonium as well as the use and effects of various tampers.

Criteria are presented for a horizontal cocurrent spray nozzle scrubbing system designed to remove fluorine and hydrogen fluoride from the 3000 cfm of ventilation air passing through the Volatility Pilot Plant. A reduction of fluorine concentration from 1520 to <2 ppm during a total release of 68 lbs, and a reduction of hydrogen fluoride concentration from 4090 to <1 ppm during a total release of 200 lbs, will adequately protect the Fiberglas media filters. Six scrubbing states each containing four nozzle-throat spray units are needed with a 5 to 10% aqueous caustic potash recycle system pumping at a maximum rate of approximately 180 gal/min, with a range per nozzle from 3 to 7 gal/min. The scrubber will be 4 ft x 4 ft x approximately 25 ft, containing a deentrainment section of baffles and demister. The associated ventilation system hardware, services, and instrumentation requirements are given. (auth)

Summary: The Regnault Method as applied to tritium purity determinations is described. The operating difficulties, such as temperature and humidity changes, static charges, excessive vibrations, contamination with air and helium, etc., and the methods currently in use for minimizing such difficulties, are discussed. A discussion of ion-chamber calibrations, and the correlation of ion-chamber results with Regnault Method results, are included. A precision of ±1% has been obtained, but the accuracy is not yet known.

The purpose of this note is to recalculate the semi-empirical curve of neutron yield vs. deuteron energy originally obtained by H. York in order to predict, using it and the best available data, what yields may be expected for deuterons on uranium in the extrapolated energy region.

Performance and boundary-layer data were taken in a 12 degree 10-inch inlet-diameter conical diffuser of 2:1 exit- to inlet-area ratio. These data were taken for two inlet-boundary-layer conditions. The first condition was that of a thinner inlet boundary later (boundary-layer displacement thickness, delta* approximately equal to 0.034) produced by an inlet section approximately 1 inlet diameter in length between the entrance bell and the diffuser. The second condition was a thicker inlet boundary layer (delta* approximately equal to 0.120) produced by an additional inlet section length of approximately 6 diameters. Longitudinal static-pressure distributions were measured fro wall static orifices. Transverse total- and static-pressure surveys were made at the inlet and exit stations. Boundary-layer velocity distributions were measured at seven stations between the inlet and exit. These data were obtained for a Reynolds number (based on inlet diameter) range of 1 x 10(exp 6) to 3.9 x 10(exp 6). The corresponding Mach number range was from M = 0.2 to choking. At the maximum-power-available condition supersonic flow was obtained as far as 4.5 inches downstream from the diffuser inlet with a maximum Mach number of M approximately equal to 1.5. The total-pressure loss through the diffuser in percentage of inlet dynamic …