Periodic Table (IMAGE) Johannes Gutenberg Universitaet Mainz Caption Actinides are radioactive metals with atomic numbers 89 to 103 in the periodic table of elements. Credit ill./©: GSI Usage Restrictions This image may only be used in connection with the press release "Mainz U & GSI involved in EU network of PhD students for research on radioactive elements", issued by Johannes Gutenberg University Mainz on November 3, 2020. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.