ABRAHAM M. LENHOFF
University of Delalaware
Hougen Visiting Professor
Abraham M. Lenhoff was born and raised in South Africa, where he earned a Bachelor's degree in chemical engineering from the University of Cape Town. After receiving Master's and Ph.D. degrees in chemical engineering from the University of Wisconsin-Madison, he joined the faculty at the University of Delaware in 1984, where he is now the Allan P. Colburn Professor of Chemical Engineering. Professor Lenhoff is also director of the NIH-funded Center of Biomedical Research Excellence on Membrane Protein Production and Characterization at the University of Delaware. His research is focused primarily on application of principles of thermodynamics, transport phenomena, biophysics, and colloid science to protein separations and phase behavior, especially chromatography and crystallization. Professor Lenhoff has been a visiting professor at the University of Cape Town, South Africa, and a visiting research fellow at the University of Melbourne, Australia. He received the 2009 ACS Award in Separations Science and Technology and the 2009 Alan S. Michaels Award in the Recovery of Biological Products from the ACS Division of Biochemical Technology. He is a fellow of the American Association for the Advancement of Science and the American Institute for Medical and Biological Engineering.
Hougen Lectures, Fall 2010
MOLECULES, PARTICLE, OR SOMETHING ELSE: PROTEINS AND THEIR SOLUTION THERMODYNAMICS
Tuesday, September 21, at 4:00 p.m. (refreshments at 3:30 p.m.)
Room 1800 Engineering Hall
The thermodynamics and phase behavior of protein solutions are exploited in numerous applications, such as precipitation and crystallization in protein separations, crystallization in structural biology and gelation in food processing. However, the relation of these operations to the solution properties and the phase diagram is not always clearly defined and detailed phase diagrams have been measured only sparingly, so the phase diagram per se has found only limited use in seeking optimal process conditions. This presentation will discuss efforts to measure protein interactions efficiently and to relate them on the one hand to protein structural information, and on the other to the thermodynamic fundamentals and protein phase behavior. Molecular mechanics simulations are used to explore the mechanistic basis for sometimes counterintuitive trends in interaction measurements, while the phase diagram for short-ranged colloidal interactions is used to organize measurements of phase behavior. A key feature is the distinctive and complex nature of protein solution behavior, which gives rise to a rich variety of physicochemical phenomena and ultimately makes life possible, but remains beyond the capabilities of current simulation methods.
THE COLBURN PAPERS
Tuesday, November 2, at 4:00 p.m. (refreshments at 3:45p.m.)
Room 1800 Engineering Hall
Allan P. Colburn was Olaf A. Hougen's first graduate student at the University of Wisconsin, and distinguished himself in his post-Wisconsin career at the DuPont Company and at the University of Delaware despite his death at a relatively young age. The University of Delaware Library has a collection of Colburn's early papers, including a recently acquired extensive set of class notes from his UW classes in the 1920s. This presentation will use the window provided by these documents to explore characteristics of chemical engineering education and research in the 1920s and 1930s, including some of the early steps in transport phenomena.