The following report describes work that was udertaken to determine whether a homogeneous breeder reactor using an alkili metal hydroxide solution is capable of breeding.

It is well known that for many years x-rays have been used in the dental profession as a potent diagnostic tool. Deprived of this means of exploration, the dentist and patient alike would be at a great disadvantage. In spite of the necessity of x-rays in the dental field, little has been done, however, to protect the patient and the dentist from unnecessary exposure. X-rays cannot immediately be felt or seen, and therein lies the hazard attending their use. What cannot be sensed is often ignored, and through unconcern and neglect an exposure resulting in biological impairment or damage may result. It was felt therefore, that the potential hazard occurring during oral roentgenography should be investigated and that the results of the investigation would be of interest to the dental profession. Radiation survey results are shown for six dentists' offices in the San Francisco Bay area.

Abstract: An airborne radiometric survey of parts of the east flank of the Big Horn Mountains was begun on June 23, and completed on August 27, 1952. An area of approximately 250 square miles was covered, and only two anomalies were found in the entire area. Flight lines were arranged in accordance with the geology of the area, particular attention being given to formations the stratigraphic equivalents of which are known to be uranium bearing in other areas. Two additional zones of radioactivity were found by ground investigation, but assays from both the ground and the airborne discoveries showed no economic uranium deposits.

During the preliminary operaton of a volatilization apparatus it became apparent that a large stopcock in the high vacuum side of the oil diffusion pump was quite unsatisfactory. Since it was necessary to mount the stopcock in a relatively inaccessible location, the difficulty of turning the plug and the consequent necessity of regreasing the valve approximately every week were real problems. Also, it became apparent that an increased pumping speed through the valve would be required. Since a larger stopcock was out of the question, a type of valve reported by Stern was modified in design and was bulit into the apparatus.

None

None

The commutation relations of an arbitrary angular momentum vector can be reduced to those of the harmonic oscillator. This provides a powerful method for constructing and developing the properties of angular momentum eigenvectors. In this paper many known theorems are derived in this way, and some new results obtained. Among the topics treated are the properties of the rotation matrices; the addition of two, three, and four angular momenta; and the theory of tensor operators.

Memorandum presenting the tail-pipe fuel ratio, mass flow of combustion gas, and radial fuel flow distribution on cooling requirements of tail-pipe burner with annular cooling-air passage.

Memorandum presenting an empirical cooling correlation for an experimental high-performance afterburner. The correlation relates the average combustion-chamber wall temperature at a station near the combustion-chamber outlet to the temperatures of the cooling air and combustion gas, and to the mass flows of the cooling air and combustion gas.

Report presenting a wind-tunnel investigation of two full-span and two semispan models with 45 degrees of sweepback, an aspect ratio of 5.5, and a taper ratio of 0.53. The lift and drag data obtained from tests of the semispan agreed well with data obtained on the full-span model. Results regarding a comparison of the data for the full-span and semispan models, full-span model data, and effect of surface roughness are provided.

Report presenting a theoretical investigation of the longitudinal dynamic characteristics of an automatically stabilized supersonic canard missile configuration with a target seeker sensitive to changes in pitch altitude. Variables explored include seeker gain, time delay, and non-linearities, including dead spots in the seeker.

Report presenting tests to evaluate the usefulness of available theory for the calculation of lift-curve slope and center of pressure of low-aspect-ratio, triangular, and rectangular cruciform wings in combination with a long slender body. Tests were made over a range of Mach and Reynolds numbers based on model length.

Report presenting an investigation of a swept, rectangular, supersonic scoop inlet designed to have low external drag at the design Mach number of 2.7. The inlet was tested with two simulated fuselages with circular and rectangular cross sections. Results regarding shadow photographs, pressure recovery, wedge effects, drag, boundary-layer control, Mach number distribution in diffuser, wedge loads, aspect-ratio effects, and applicability of results are provided.

Report presenting an empirical cooling correlation for an experimental high-performance afterburner. The correlation equation is useful for shortening the experimental investigation of afterburner cooling characteristics inasmuch as it provides a method for interpolating the critical wall temperatures for other combinations of operating variables.

Memorandum presenting an investigation at transonic speeds in the high-speed 7- by 10-foot tunnel to determine the hinge-moment and other aerodynamic characteristics of an inboard plug-type spoiler on a 45 degree sweptback wing of aspect ratio 3. The results indicated that the spoiler would be overbalanced at low projections through the speed range investigated and the for the same rolling moment, the spoiler hinge moments would be small in comparison with those of a plain-flap-type control.

Report presenting pressure-distribution tests on an ogive-cylinder configuration with and without longitudinal spoilers at Mach number 4.04. Spoilers were not found to cause any noticeable change in the body pressures in regions that contribute the largest amount of normal body force. Results regarding a comparison of experimentation and theory, flow separation, and cross-flow effects are also provided.

From Introduction: "During previous investigations of afterburning conducted at the NACA Lewis laboratory (references 1 to 4, for example), the objective of obtaining high exhaust-gas temperatures and, consequently, maximum thrust augmentation was compromised to some extent in order to alleviate the problem of afterburner shell cooling. The primary objective of the investigation reported herein was therefore the attainment of maximum exhaust-gas temperature imposed by the cooling techniques previously used, a secondary flow of cooling air was provided around the afterburner shell."

Report presenting an investigation in the high-speed tunnel on a 45.58 degree sweptback wing to determine the effects of a paddle balance on the control characteristics of a full-span flap-type control. The wing had an aspect ratio of 3, a taper ratio of 0.5, and an NACA 64A010 airfoil section measured in a plane at 45 degrees to the plane of symmetry. Results regarding the hinge-moment characteristics, lift characteristics, and rolling moment-characteristics are provided.

Report presenting tests at low speeds in the low turbulence pressure tunnel and the stability tunnel in order to determine the extent of any resulting oscillations of a model mounted with freedom in yaw and to demonstrate the extent to which directional fluctuations in an air stream can be responsible for the oscillations.

Memorandum presenting the effective downwash characteristics of a wing-body configuration and the body alone determined from lift measurements of a horizontal tail located 0.333 and 0.479 wing semispan above the body center line. The wing had a sweepback angle of 47 degrees, an aspect ratio of 3.5, a taper ratio of 0.2, and a thickness ratio of 0.06.

The effects of tail-pipe fuel-air ratio (exhaust-gas temperatures from approximately 3060 degrees to 3825 degrees R), radial distribution of tail-pipe fuel flow, and mass flow of combustion gas and the inside wall were determined for an experimental tail-pipe burner cooled by air flowing through and insulated cooling-air to combustion gas mass flow from 0.066 to 0.192 were also determined. Results regarding the reproducibility of combustion-gas temperature profiles, effect of variables on average longitudinal profiles of combustion-gas temperature, variation of gas temperatures near the wall with cooling-air flow and temperature, and effects of variables on transverse gas temperatures are provided.

Report presenting an investigation in the low-turbulence pressure tunnel to determine the lift, drag, and pitching-moment characteristics of a 45 degree sweptback wing with a 6-percent-thick symmetrical airfoil section designed for maximum lift at low speeds. Results regarding low-speed testing and high-speed testing are provided. Testing indicated that the new airfoil sections provided substantial improvements at low speeds without compromising performance at high speeds.

An arbitrary weak spatial distribution of vorticity can be represented in terms of plane sinusoidal shear waves of all orientations and wave lengths (Fourier integral). The analysis treats the passage of a single representative weak shear wave through a plane shock and shows refraction and modification of the shear wave with simultaneous generation of an acoustically intense sound wave. Applications to turbulence and to noise in supersonic wind tunnels are indicated.

None