For his innovation in the production and application of medical isotopes; for advancing the separation and purification of actinides and heavy elements; and for his leadership in the use of alpha emitters to save the lives of cancer patients.
For his broad scientific contributions and international reputation in aqueous chemistry and geochemistry; for his research into the structure, dynamics, and reactions at fluid–solid interfaces; and for his leadership and service to ORNL and the international scientific community.
For distinguished research on the air/surface exchange of atmospheric trace gases and particles and their interactions with the Earth's biogeochemical cycles, and for pioneering developments in atmospheric sampling methodologies with special emphasis on the global mercury cycle.
For advances in neutron and gamma-ray dosimetry, the transport of electricity through gases, and the development of laser-based one-atom detection with applications in nuclear physics, solar neutrino research, and oceanic, geologic, and environmental research
For research on the processes involved in the induction of mutations, elucidating the roles and sequences of DNA repair and replication in converting radiation or chemical damage into mutations, and for contributions to the understanding of biological control mechanisms at the cellular level