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Robert Gregory Downing (Assoc)

Research Chemist

Greg develops and applies nuclear methods to solve problems of a metrological nature. Since his career began at NIST, the improvement and application of the neutron depth profiling (NDP) technique and low-background gamma-ray spectrometry have figured prominently in his activities. He applies NDP for the study of semiconductors, batteries, fusion wall material, glasses, optical wave guides, wear studies and more. In addition, he studies lithium and boron using a variety of techniques for SRM development and studies in nutrition, toxicology, botanical and biological matter, minerals, water, etc. A portion of his career has included the development and application of neutron optics and high spatial resolution neutron and particle detectors.  For this work he holds several patents. He has consulted and taught for the International Atomic Energy Agency. Greg continues to mentor students of all academic levels. He has presented over 100 professional talks throughout the world and has published extensively. He also serves on a number of NIST safety committees.

Membership and Professional Activities:

  • International Union of Pure and Applied Chemists (IUPAC)
    • Fellow (1998- present)
    • Committee membership (1992-1997)
  • Sigma Xi, The Research Society - member (1979 – 2016)
  • American Chemical Society - member (1982 – present)
  • American Nuclear Society (ANS) (2005-present)
    • Isotope and Radiation Division, Chair (2008-2009)         
    • Isotope and Radiation Division, Co-Chair (2007-2008)
    • Isotope and Radiation Division, Executive Board
    • Biology and Medicine Division, Co-Chair (2016-2017)
    • Biology and Medicine Division, Executive Board (2016- present)
  • Journal of Radioanalytical and Nuclear Chemistry, Associate Editor (past) 
  • The Foundation for Chemical Research, Inc., University of Missouri, Rolla, MO
    • Advisory Board Member (2002-2007)
  • NIST Committees
    • NCNR Safety Evaluation Committee, Chair (2010-2016)
    • NIST Isotopes and Radiation Safety Committee (alternate)


  • Distinguished Alumni Award (2007) – Missouri Western State University, St. Joseph, Missouri
  • "R&D 100" award (1995) shared by X-Ray Optical Systems, National Institute of Standards and Technology, and University at Albany - SUNY
  • U.S. Department of Commerce Bronze Medal, December, (1994) (National Institute of Standards and Technology Award) - Neutron Focusing
  • U.S. Department of Commerce Bronze Medal, December (1990) (National Institute of Standards and Technology Award) – Neutron Depth Profiling
  • National Bureau of Standards Applied Research Award (1986) – Neutron Depth Profiling


Created October 9, 2019, Updated June 15, 2021