About the Author ITZHAK THOMAS PLATZNER is chief chemist and head of the mass spectrometry laboratory at the Nuclear Research Center-Negev (NRCN), Israel. He received his PhD from the Weizmann Institute of Science, Israel in 1966 in photochemistry and spectroscopy of phosphorus compounds, for which he gained his first experience in isotope ratio mass spectrometry (IRMS). Since he established the mass spectrometry laboratory at NRCN in 1967, he has worked extensively in isotope ration analysis. His curren research interests include IRMS of solids and gases and applications of ICP-MS to IRMS...