86. Smirnov, N. S. PeOfuan Ur ih INFLUENCE OF AN ATCMIC EXPLOSION ON THE STATE OF THE ATMOSPHERE. ‘ Ser,Geofiz, Now20, Loeves. jeas He Aarestiias The author reviews trie‘iy various American, Western European and Japaneze studies deaing with the effect of atomic explosicns upcn the state of atmosphere. He then considers the possitie changes in the radiation radioactive properties cf the atmosphere that can be caused by the explosion of one atomic bomb, how the increase in radioactivity can influence the radiation balance of the earth, the effect of atomic explosions upon the dust, ion and aeryvsc!] content of the atmosphere and the meteorolcgicas effects of atomic explosions such as the occurrence of fogs, etc. 87. Terentiuk. F. MEASUREMENT OF ARTIFICIAL RADIOACTIVITY IN THE ATMOSPHERE AT OTTAWA, CANADA. 139 (1958). CanadianJournalofPhysics 36, 136= In recent years there has been considerable interest in the artificial radioactivity in the atmosphere originating from atomic and thermonuclear explcsions. For the past year da:liy measurenent2 of radioactivity have been made at Ottawa. The samp.ing times corresponded to air volumes of %2° cubic metric and 2,000 cubic meters, respectively. Filters were kept for a period of 3 days before measurements were made in order to permit Maturai activity resulting from daughter products of radon and thoron tc de.ay tc a negligible vaiue. Measurements of the gross beta activity from the filters were made directriy end -window Geiger tubes. Fiiters shewing con71asrable initial radioactivity were measured at intervals cf a few days in orcar to obtain the rate of decay of the acilyity, ‘+ wae hoped that the data obtained would make °° possitis to fix the date of the explosion responsit’« fcr he f1.%¢r activity but the fixing cf dates was tery cuncertair.

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