A tale of openness and secrecy: The Philadelphia Story
A now little-known manuscript prepared by nine young physicists as a statement about the futility of scientific secrecy quickly became a test of the limits of free discourse in the nuclear age.
Atomic Energy for Military Purposes
IN Nature of December 29, 1945, p. 768, an article by Prof. N. Feather surveyed and discussed the official American report on the development of the atomic bomb which was issued under the title “Atomic Energy for Military Purposes” and was quickly to be known as the Smyth Report, after its author. The report was re-issued in Great Britain by H.M. Stationery Office. Now the Princeton University Press has published the pamphlet in book form “as a public service in accordance with its purpose as a non-profit organisation seeking to disseminate the results of scholarly and scientific research”. No royalty or other compensation is being paid to the author.Atomic Energy for Military PurposesThe Official Report on the Development of the Atomic Bomb under the auspices of the United States Government, 1940–1945. By Henry DeWolf Smyth. Pp. viii + 308 + 8 plates (Princeton, N.J.: Princeton University Press; London: Oxford University Press, 1946.) 12s 6d net.
Effects of Equipment Dimensions on Liquid Mixing Time of Bubble Column with Draft Tube
The liquid mixing time of a bubble column with a draft tube is experimentally studied. The diameter and height of the column, the diameter and length of the draft tube, and the mode of sparging gas were changed and the liquid mixing time was measured.The lengths of bottom and top clearances have significant effects on the liquid mixing time. The liquid mixing time increases with increasing column aspect ratio of height to diameter. The liquid mixing time of the bubble column with a draft tube is longer than that of a standard bubble column when the column aspect ratio is relatively high. The liquid mixing time has a minimum when the diameter ratio of draft tube to column is 0.5 to 0.6. These effects of equipment dimensions are expressed by an equation. In the experiment using different solutions, the liquid mixing time becomes shorter with increasing liquid surface tension, or with increasing liquid viscosity.