Report issued by the Bureau of Mines over studies of the processes used in oil-shale assay methods. Updated methods are provided from a previous report on the same topic. This report includes tables, graphs, and illustrations.

Report issued by the Bureau of Mines over petroleum-engineering studies conducted at the Atlanta oil field. The methods used for the study are presented and discussed. This report includes tables, maps, illustrations, and photographs.

Report issued by the Bureau of Mines over studies conducted on vanadium deposits in Lincoln County. As noted in the introduction, "the following report covers the history of the district, outlines the physical features and communications, mentions the property, and notes the ownership. The deposits and ore are described, and work performed by the Bureau of Mines is explained in detail" (p. 1). This report includes tables, and maps.

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.

Abstract: "The sensitivity to fast neutrons of a CP Meter ionization chamber of the type used for health physics beta and gamma survey measurements has been investigated."

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."

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 discussing the results of research conducted by the Hanford Works Analytical Research Group during the period from March 1949 to April 1949.

Preface: The existence of adequate experimental equipment, in particular the two operating cyclotrons of the Radiation Laboratory and the large 184-inch unit under construction, together with a nucleus of trained personnel, made it inevitable that work in connection with the war effort would be prosecuted vigorously at the University of California.

Preface: The existence of adequate experimental equipment, in particular the two operating cyclotrons of the Radiation Laboratory and the large 184-inch unit under construction, together with a nucleus of trained personnel, made it inevitable that work in connection with the war effort would be prosecuted vigorously at the University of California.

Introduction: The general project of correlating soil properties with geologic information, one phase of which is described in this report, consists in comparing soil properties with soil types and with their geologic history and environment in order to determine what correlations are possible.

Final report describing the development and usage of an automatic decade scaler which operates for a fixed number of counts, developed for use with a Geiger tube.

From Summary: "Despite the development of relatively ice-free fuel-metering systems, the widespread use of alternate and heated-air intakes, and the use of alcohol for emergency de-icing, icing of aircraft-engine induction systems is a serious problem. Investigations have been made to study and to combat all phases of this icing problem. From these investigations, criterions for safe operation and for design of new induction systems have been established. The results were obtained from laboratory investigations of carburetor-supercharger combinations, wind-tunnel investigations of air scoops, multicylinder-engine studies, and flight investigations. Characteristics of three forms of ice, impact, throttling, and fuel evaporation were studied."

A method introduced by Munk is extended to prove that the light-curve slope of thin wings in either subsonic flow or supersonic flow is the same when the direction of flight of the wing is reversed. It is also shown that the wing reversal does not change the thickness drag, damping-in-roll parameter or the damping-in-pitch parameter.

Report presenting an analysis of the measurements of drag-angle oscillation of a helicopter rotor made with the helicopter apparatus to determine both the natural frequencies and the damping required to prevent excessive drag-angle-oscillation response to various throttle and control movements. Results regarding symmetrical oscillations, unsymmetrical oscillations, blade damping, and general discussion are provided.

"Results are presented of calculations for the elastic buckling load of a simply supported flat rectangular plate of uniform thickness subjected to unequal compressive stresses at two opposite edges, with a linear variation of stress between the two edges. The difference between the compressive stresses at the two loaded edges is equilibrated by shear stresses along the other two edges. The results show that a plate with a linear stress gradient will buckle at an average stress that is lower, but at a maximum stress that may be appreciably higher, than the uniform compressive buckling stress of the same plate" (p. 1).

Report presenting a wind-tunnel investigation to determine the boundary-layer and stalling characteristics of the NACA 63-009 airfoil section. Pressure distributions, tuft studies, and boundary-layer measurements were obtained. A localized region of flow separation was found to develop on the upper surface of the airfoil near the leading edge.

"This report is the result of the first part of a broad program to analyze the transient motions of a helicopter, which occur in the various phases of flight following power failure" (p. 1).

"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).

Note presenting an investigation of the use of measured static pressures in a vaneless-diffuser passage for determining centrifugal-compressor performance. The general effects of diffuser-wall-surface friction were studied to locate the regions in the vaneless-diffuser passage where the most valid evaluation can be made by the static-pressure method.

From Introduction: "Although the aerodynamic characteristics of the components of such configurations may be well known, the mutual interference resulting from combining the wings, as well as the wings and body, may be so great that is desirable to study the aerodynamic properties of the complete configurations. Two methods of handling this problem are presented in this report. The first method is essentially an extension of the theory for slender wing-body combinations of reference 1 to determine the load distribution, forces, and moments exerted on slender cruciform-wing and body combinations inclined simultaneously at small angles in pitch and yaw. "

Note presenting meteorological data from flight observations in icing conditions during the first 5 months of 1948. A total of 335 measurements of liquid-water content and mean-effective drop diameter were obtained by the multicylinder method in the course of 40 flights in icing conditions covering most of the northern United States. Information regarding the discontinuous character of icing clouds, variation of average liquid-water content with extent of icing conditions, and variation of drop diameter from year to year and with geographic location are provided.

Report presenting the results of a preliminary investigation of a scale model of a convertible-type airplane in the full-scale tunnel. The maximum lift and stalling characteristics of several configurations, the longitudinal stability characteristics, and the effectiveness of the control surfaces with the propellers removed are provided. Results regarding the propulsive characteristics, and effect of propeller operation on the lift and static thrust of the model propellers are also provided.

Report presenting an investigation using a 4600 pound-thrust turbojet engine as part of a program to determine the comparative performance of fuels conforming to specifications AN-F-58 and AN-F-32. Results regarding the altitude performance, altitude low-speed blow-out limits, idling limits of fuel-metering control, altitude windmilling starts, carbon-deposition rates, and iron oxide contamination are provided.