 569  538. Electrical conductivity was not only markedly affected by the pressure but the effect in the two similar semiconductors was opposite. Conductivity in the two materials differed by a factor of 1012. Conductivity of the germanium semiconductor containing arsenic impurities increased 10'4 times with the application of pressure. In the antimony-doped germanium semiconductor, conductivity decreased by a factor of 108. Impurities in semiconductors have been assumed to enhance conductivity because they add free electrons to the crystal. However this theory does not explain the opposite results obtained with the two different impurities added to germanium crystals. 539. That intoxication with meat occasionally may be produced in animals without Eck's fistulas suggests that similar toxic products may be formed even in normal animals and be destroyed by the liver. Results of excessive feeding of meat should be compared after various alterations of the portal and inferior vena caval circulation in relationship to Eck's fistula. Such information would determine whether intestinal function is altered so that more toxic material is formed or whether the altered circulation to the liver is a factor in the destruction of such substances. 540. Robert S. Bell, company president, says the technique would increase communications efficiency by eliminating redundant data prior to transmission, thereby allowing more information to be transmitted over existing facilities. «It is similar to dehydration». Bell explains. «Data is compressed during transmission and expanded to its original form at the receiving end». Bell says the technique was conceived to reduce cost and weight in satellite and telemetry applications, but that it could be used for television. 541. The banding ratio was defined as the ratio of free ferrite path in the rolling direction to that in the thickness direction. Care was taken to compute a value only after sufficient counting that the percentage of ferrite (or pearlite) was the same (within 0.5%) in both directions. With this procedure the ferrite and pearlite banding ratios are identical. From Fig. 1 the banding ratio is seen to vary in an essentially inverse way with grain size, banding being more pronounced in the steel of finer grain size, irrespective of rolling process. 542. Solid solutions were being formed between the green tertiary phosphate and one or more acid components. Solid solutions have been classified by Roozeboom and by Ricci as being of six types readily distinguishable by the use of the Roozeboom diagram, in which the percentage of A in the liquid is plotted against that in the solid in contact (the water content being ignored), i. e., 100 A/(A + B)%, where A and B are the two salts concerned. Several possibilities for A and B were tried but in no case could the present system be described as being one of the six types. 569 |
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