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 pioneering research in ecosystem theory, ecological modeling, error analysis, hierarchy theory, and landscape ecology and for the development of basic applications in risk assessment and regional environmental analysis.
For distinguished research in the field of risk assessment, including pharmacokinetic and pharmacodynamic models, interspecies extrapolation, and human exposure to dioxin and other background contaminants, and for significant contributions to environmental policy through pioneering investigations of the effectiveness of remediation technologies and through service on national and international advisory panels and boards
For basic studies in the fracture of and toughening mechanisms in ceramics and ceramic composites, in the establishment of the relationships between microstructure and composition and mechanical behavior, and in the development of advanced ceramic materials.
For ideas and techniques which have opened new frontiers in chemical research and now play major roles in the study, understanding, and use of photoionization and photoelectron spectroscopy in studies of "hot atom" chemistry and work with multiply charged molecular ions.