Assertion: plutonium | /r/HasProperty | synthesized by seaborg
Facets:
value: in 1940
type: TEMPORAL
Source sentences:
text: Plutonium was synthesized by Seaborg, McMillan, Kennedy and Wahl in 1940 by deuteron bombardment of uranium in a cyclotron (a device used to accelerate atomic particles) at Berkeley, California, USA.