Time-Dependent Material Response of Plant Cell Walls and its Importance for Measurements and Modeling

Plant cell walls are complex, fiber-reinforced biocomposites that change during the growth process. One very important aspect for growth is the time-dependent (viscoelastic) nature of the cell wall that allows the wall to relax and expand. In this presentation, the role of viscoelasticity and its impact on measurement interpretation and modeling are discussed. In particular, the computational modeling of cell wall behavior must include an appropriate time-dependent component in order for force-displacement responses to have physical relevance. In addition, model inputs are often derived from scanning probe microscope experiments (e.g., nanoindenter, atomic force microscope) that are now being applied to plants. However, data analysis is often made under the assumption of a quasi-static material response for which the loading rate is presumed unimportant. Here, the impact of such assumptions is discussed and quantified using several examples. Prospects for modeling of plant cell clusters will also be examined.

Brief Biography

Joseph A. Turner is currently the Robert W. Brightfelt Professor of Mechanical and Materials Engineering at the University of Nebraska-Lincoln (UNL). He received his B.S. (Eng. Sci.) and M.Engr. (Eng. Sci. Mech.) degrees from Iowa State University in 1988 and his Ph.D. (Theoretical and Appl. Mech.) from the University of Illinois at Urbana-Champaign (UIUC) in 1994. After a postdoctoral experience at UIUC, he served as an Alexander von Humboldt Postdoctoral Fellow at the Fraunhofer Institute for Nondestructive Testing (IZFP) in Saarbrücken, Germany before joining UNL in 1997. He is a Fellow of the Acoustical Society of America and recipient of the Wilhelm Bessel Forschungspreis from the Alexander von Humboldt Foundation (2014). His research interests are associated with characterization of a variety of materials and their microstructures using ultrasound/acoustics, nanoindentation, and atomic force microscopy with analytical, numerical and experimental components.

 

Joseph A. Turner

Robert W. Brightfelt Professor of MME

Mechanical and Materials Engineering

University of Nebraska-Lincoln, Lincoln, NE 68502

jaturner@unl.edu

Event Quick Information

Date
23 Jan, 2018
Time
01:00 PM - 02:00 PM