Volume 3, Issue 4, 01 October 1932
Index of content:
3(1932); http://dx.doi.org/10.1063/1.1745095View Description Hide Description
The inner structure of Dowmetal fabricated by various processes, such as forging, rolling, extruding and drawing, has been studied by means of x‐ray diffraction. The x‐ray diffraction patterns are identified by comparing them with computed fiber patterns for the close‐packed hexagonal system, c/a=1.62. Three distinct structures are obtained—a  fiber structure at ordinary temperatures and a  fiber structure at temperatures higher than about 450°C with the fiber axis, in both cases, in the direction of extrusion or drawing, and a  fiber structure with the fiber axis in the direction of forging. The difference in the structure of metal extruded at low and high temperatures is discussed in terms of the glide systems of magnesium.
3(1932); http://dx.doi.org/10.1063/1.1745096View Description Hide Description
It is shown by x‐ray diffraction methods that electrodeposits from copper acetate solutions consist principally of a mixture of crystals of copper and cuprous oxide and that the proportion of cuprous oxide deposited with the copper increases when the bath is made less acid.Rectification or photoelectric properties such as are exhibited by cuprous oxide prepared on the surface of copper were not observed for the electrodeposits.
3(1932); http://dx.doi.org/10.1063/1.1745097View Description Hide Description
3(1932); http://dx.doi.org/10.1063/1.1745098View Description Hide Description
3(1932); http://dx.doi.org/10.1063/1.1745099View Description Hide Description
The general problem of elimination of sand, cuttings, and gas from aqueous dispersions of clay, commonly used in the rotary method of drilling oil wells, with reclamation of the colloidal content of the drilling fluid, is considered. Various mechanical devices for this purpose are briefly described and available data compared with laboratory findings on the rates of settling of particles from clay drilling fluids after chemical treatment. The colloid physics underlying the efficiency of chemical treatment is discussed. Graphs are given showing the superiority of chemical treatment of drilling fluids as compared with mechanical methods for reclaiming spent fluids. Treatment by chemical reagents has the great advantage of requiring no new equipment or expensive installation, and individual wells may be treated economically. Certain recommendations are made for maximum efficiency of the chemical method for field practice.
3(1932); http://dx.doi.org/10.1063/1.1745100View Description Hide Description
A gaseous discharge lamp in combination with a special electrical circuit is described with which a high‐efficiency conversion of 60‐cycle a.c. power into 1000‐cycle pulsating light is obtained. The efficiency of this device is 17 lumens per watt as compared to 6 lumens per watt for an incandescent lamp with a mechanical shutter. As the modulated light is designed for the use in beacons and for the detection by means of a photoelectric tube and tuned amplifier, the component of fundamental frequency is the only important one. In a mathematical analysis of different wave shapes, the fundamental component is calculated as a function of the average light output; also the efficiency of a modulated neon discharge.