Johanna Levelt Sengers
L'OREAL-UNESCO For Women in Science Laureate 2003 for North-America
National Institute of Standards and Technology (NIST), Gaithersburg, Maryland
Scientist Emeritus, Thermophysical Properties
As a research physicist, Levelt Sengers and her collaborators worked on critical phenomena in fluids and fluid mixtures, from theory to experiment and databases for practical application. They developed critical-region scaling concepts for fluids and fluid mixtures, and for solubility behavior near a solvent's critical point. They also performed measurements of density, phase behavior and other properties of industrially important fluids such as carbon dioxide, ethylene, water and geothermal fluids. As a NIST group leader (1978-87), Levelt Sengers oversaw projects related to alternative refrigerants, ionic fluids criticality, and supercritical fluids. She co-organized the first NATO Summer School on Supercritical Fluids in Kemer, Turkey, in 1993. She has published extensively in the archival literature, and contributed 14 book chapters. Since her retirement from NIST in 1994, she has written on the history of her field of thermodynamics, including a book titled How Fluids Unmix in 2002. Very recently, as the co-chair of a panel of the InterAcademy Council, she co-authored a report "Women for Science" to advise the world's science and engineering academies on how to attract, retain and promote more women in science and technology worldwide. Levelt Sengers is a fellow of ASME, the American Physical Society and the American Association for the Advancement of Science, and an Honorary Fellow of the IAPWS. She was elected to the National Academy of Engineering and the National academy of Sciences, and is a correspondent of the Royal Netherlands Academy of Arts and Sciences and a member of the Royal Holland Society of Sciences and Humanities.