Nuclear physics and radiochemistry · 1905–1989
Emilio Segrè
Segrè trained in Rome under Fermi, worked on slow-neutron reactions, and moved to Berkeley, where the cyclotron produced irradiated materials that nobody had yet examined chemically. He was stripped of his Palermo position by Italy’s racial laws in 1938 and stayed in the United States, later leading a group at Los Alamos. He shared the 1959 Nobel Prize in Physics with Chamberlain for the discovery of the antiproton.
Explore the supporting references at the foot of this article.
Contribution & context
With Perrier he identified technetium in 1937 in a molybdenum foil sent from the Berkeley cyclotron, filling the table’s longest-standing gap; with Corson and Mackenzie he produced astatine in 1940 by bombardment of bismuth; and with Kennedy, Seaborg and Wahl he took part in the identification of plutonium.
LANL Periodic Table — TechnetiumNIST — TechnetiumRSC Periodic Table — Technetiumnature.com — TechnetiumUSGS — Technetium
Discoveries in context
Filling the gaps the table left open ↗
Mendeleev left blank places and stated what should occupy them; the elements that arrived turned an arrangement into a predictive instrument, and the last two gaps had to be manufactured.
Sources & further reading
- LANL Periodic Table — Technetium ↗Los Alamos National LaboratoryReference explanation · Source checked
- NIST — Technetium ↗National Institute of Standards and TechnologyReference explanation · Source checked
- RSC Periodic Table — Technetium ↗Royal Society of ChemistryReference explanation · Source checked
- nature.com — Technetium ↗nature.comReference explanation · Source checked
- USGS — Technetium ↗United States Geological SurveyReference explanation · Source checked
Sources and further reading. What the review labels mean