Activities in a program to develop techniques in the use of pulsed neutron sources to measure shutdown parameters related to large thermal power reactors are reported. The experimental work centers around aspects of detecting neutrons in the presence of 10/sup 7/ r/hr gamma fields. Boric acid experiments and Humboldt Bay experiments are reported.

Report presenting an investigation of a pylon-mounted-store airplane configuration in the supersonic pressure tunnel at a Mach number of 1.61. Forces and moments of a complete wing-fuselage-store-pylon combination was measured for a variety of pylon-mounted store locations below the wing. Results regarding the effect of store position on the aerodynamic characteristics in pitch, effect of store position on the aerodynamic characteristics in sideslip, store fins and store tail cone, double-store installation, effect of pylon location, and relative contribution of store-pylon forces toward total force are provided.

Memorandum presenting an experimental investigation of the pressure-recovery performance of a fixed-geometry, two-cone, two-drag inlet at Mach number 2.95. Low drag was achieved by use of an internally cylindrical cowl with rapid flow turning that was within 4 degrees of the wedge angle for shock detachment. Results regarding the inlet performance and evaluation of inlet performance are provided.

Report presenting aerodynamic forces for an external-store installation on the Douglas D-558-II research airplane. Store-pylon, pylon-alone, and fin loads were determined during angle-of-attack and angle-of-sideslip maneuvers over a range of Mach numbers. Results regarding the side-force coefficients, normal-force coefficients, external-store-load parameters, external-store fin loads, and wing-panel aerodynamic loads are provided.

Report presenting preliminary flight surveys of noise inside fuselages and in the fuselage boundary layer, which were obtained in order to determine the magnitude of the noise and relative importance of engine noise and noise due to the boundary layer. Results indicated that the sound-pressure level continued to increase with airspeed to the highest airspeed obtained, although the rate of increase at supersonic speeds was less than at subsonic speeds. Testing occurred on the B-47A and D-558-II airplanes.

Report presenting the results of an investigation of the static longitudinal stability and control characteristics of a canard airplane configuration without analysis over a range of Mach numbers. Data are presented for various combinations of the body, canard, wings, and vertical tail at 0 and 5 degrees of sideslip over a range of angles of attack and canard deflection angles.

The following report describes studies of thermodynamic equilibria of vanadium in aqueous systems as applied to the interpretation of the Colorado Plateau ore deposits.

Memorandum presenting a study of the performance of swirl-can combustor elements for an experimental short-length turbojet combustor utilizing hydrogen fuel at high-altitude operating conditions. Fuel was injected into each element through a tangential, sonic orifice that created a swirling fuel-air mixture within each element. Results regarding combustor blowout, combustion efficiency, outlet temperature distribution, and preliminary performance of multielement combustor are provided.

Report presenting a study of the performance of "swirl-can" combustor elements for an experimental short-length turbojet combustor utilizing hydrogen fuel at high-altitude operating conditions. Fuel was injected into each element through a tangential , sonic orifice that created a swirling fuel-air mixture within the element. Results regarding combustor blowout, combustion efficiency, outlet temperature distribution, and preliminary performance of the multielement performance of multielement combustor are provided.

Bench scale studies have been made of the recovery of uranium from acid leach liquors (and slurries) by solvent extracting with di (2-ethylhexyl) phosphoric acid in an organic diluent. Uranium may be stripped from the organic solvent by either alkaline or acidic reagents, the former having been studied in greater detail. On the basis of these tests, a recovery process may be considered which shows promise both from the standpoint of operation and chemical costs. Under proper conditions, vanadium can also be extracted by the di (2-ethylhexyl) phosphoric acid and stripping again may be accomplished with either acidic or alkaline reagents. Preliminary studies have been made of these possibilities. In addition to di (2-ethylhexyl) phosphoric acid, some other organophosphorus acids, have been cursorily examined in respect to their extraction and/or stripping performance.

Introduction: "The uranium-5 w/o chromium alloy has been intensively investigated for use in a power reactor in the as-cast condition. However, when cast sample fuel elements were subjected to irradiation, their stability was found to be unsatisfactory. In order to improve the behavior of the alloy, a program of grain refinement by heat treatment was begun. The effect of chill casting on the heat-treated grain size was also investigated."

From Introduction: "In reference 1, in which the performance of conical supersonic scoop inlets on circular fuselages is reported, the drag of the bottom-inlet configuration was considerably higher than for the top inlet."

"The performance of liquid fluorine and liquid ammonia as a propellant combination was evaluated in 1000-pound-thrust rocket engines operated at a chamber pressure of 600 pounds per square inch absolute. Values of specific impulse, characteristic velocity, thrust coefficient, and heat rejection were obtained as functions of propellant mixture ratio for each of four injectors: a triplet, a showerhead, and two like-on-like types" (p. 1).

Memorandum presenting a study of the ignition of ammonia and mixed oxides of nitrogen at 160 degrees Fahrenheit made with and without fuel additives utilizing small-scale rocket engines of approximately 200 pounds thrust. All experiments were conducted at sea-level pressures except two at a range of pressure altitudes. Results regarding the use of lithium as a catalyst, calcium as a catalyst, and no apparent catalyst are provided.

Report presenting a study of four short annular diffusers with different diffuser passage area variations and with various combinations of straightening vanes, vortex generators, splitters, and boundary layer suction for flow control. Results regarding turbine discharge whirl, diffuser passage modification, and boundary layer control are provided.

Report presenting an experimental investigation to determine the effect of several wedge-type boundary-layer diverters on drag and inlet pressure recovery in the 8- by 6-foot supersonic wind tunnel at Mach numbers of 1.5, 1.8, and 2.0. The model consisted of two rectangular ramp-type inlets mounted on the NACA RM-10 body of revolution. Results regarding variation of inlet pressure recovery and configuration drag with inlet mass-flow ratio, changes in the shock pattern off the inlet ramp, pressure-recovery-mass-flow characteristics, and drag coefficients are provided.

Report presenting an exploratory investigation of three aluminum disoaps of C(sub 8) acids to determine the gelling properties and stabilizing ability in slurries of 50 percent magnesium power and JP-4 fuel. All of the soaps were found to gel the slurries satisfactorily and to exhibit adequate reproducibility of gel properties. Results regarding the soap behaviors, effects of temperature, viscosity, and formation of the gel structures are provided.

"Preliminary results of approximately 350 maneuvers of all types performed by a Lockheed F-94B jet interceptor airplane during normal operational training are presented in time-history form and are summarized as maximum load factors, control rates, angular accelerations, and sideslip angles plotted against indicated airspeed. The results were obtained from approximately 350 maneuvers performed by a Lockheed F-94B jet interceptor airplane during squadron operational training" (p. 1).

This report discusses a proposed method for treating the effect of increasing critical mass of plutonium solutions, which occurs when hydrogen density is reduced by dilution with heavier nuclei.

Report discussing the progress made on a research project for the preparation of ductile zirconium during April 1949.

The following report describes procedures taken to utilize the photelometer to procure the most rapid and reliable determinations, but the goal of the tests presented was to create satisfactory dispersions of particles to analyze.

The effects on dynamic lateral stability and controllability of some of the important aerodynamic and mass characteristics are discussed and methods are presented for estimating the various stability parameters to be used in the calculation of the dynamic lateral stability of airplanes with swept and low-aspect-ratio wings.

This report describes the use of pile control over atomic power, including the different methods of control.

Technical report includes three reports of research progress: 1)Meson Mass Determination by Grain Counting, W. H. Barkas; 2) The Magnetic Beta Ray Lens Spectrograph, A. C. Helmholz; 3) Anthracene Counters, E. Martinelli.