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Radioactive Organic Bromo-Compounds


CONSIDERABLE attention has recently been focused on the use of artificially radioactive substances in biological work. The radioactive isotope 82Br has been chosen by us because it has a conveniently long half-life (34 hours), it is chemically reactive, it gives off gamma-rays which aid in its detection, and finally, it can be prepared from 81Br either by the action of slow neutrons or deuterons. Slow neutrons are easily available from the radon-beryllium reaction. Fast deuterons from the cyclotron or any other suitable high-energy source may be used either as projectiles themselves or for the production of slow neutrons as in the lithium reaction below. The relative abundance of 81Br in natural bromine is 49.3 per cent. Contamination of radioactive 82Br by other isotopes is of no consequence since bromine forms no non-bromine radioactive elements on bombardment by slow neutrons or deuterons1.


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  2. 2

    Szillard and Chalmers, NATURE, 134, 462 (1934).

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FRIEDMANN, E., SOLOMON, A. & WERTHESSEN, N. Radioactive Organic Bromo-Compounds. Nature 143, 472 (1939).

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