| 释义 |
thoron Chem. and Physics.|ˈθɔərɒn|
[a. G. thoron (C. Schmidt 1918, in Zeitschr. f. anorg. Chem. CIII. 114), f. thorium + -on2.
Quot. 1920 represents an independent coinage.]
A radioactive isotope of radon, atomic weight 220, that is a gaseous decay product of thorium, being formed by the decay of radium 224; thorium emanation.
1918Jrnl. Chem. Soc. CXIV. ii. 306 A rational system of nomenclature for the radioactive elements and their degradation products is suggested. Radium emanation is given the name Radon, Ro... The other emanations become Thoron, To, and Acton, Ao. 1920E. Q. Adams in Jrnl. Amer. Chem. Soc. XLII. 2206 The names ‘radium emanation’, ‘actinium emanation’ and ‘thorium emanation’ have been shortened, respectively, to ‘radon’, ‘actinon’ and ‘thoron’, names which suggest that the element in question is an inert gas. 1938R. W. Lawson tr. Hevesy & Paneth's Man. Radioactivity (ed. 2) xi. 132 The emanation of thorium (thoron) decays with a half⁓value period of 55 seconds. 1961New Scientist 2 Nov. 290/3 The filter is placed in a lead cask and, after allowing four days for the decay of the ‘daughter’ products of natural radon and thoron, the total beta-activity of the sample is recorded. 1981Indian Jrnl. Earth Sci. VIII. 1 (heading) On the behaviour and measurement of thoron (Rn220) in soil. 1983Canad. Mining Jrnl. Mar. 34/1 Measurements were carried out to estimate the radon and thoron daughter levels. |