演讲嘉宾:
Emeritus Prof Leonid M. Pismen
Fellow of American Physical Society
Editor of the European Physical Journal- Special Topics
Department of Chemical Engineering
Technion-Israel Institute of Technology
时间:2019年1月4日 上午10:00-12:00
地址:be365体育平台 木兰楼A1006
主持人:龚晓波 副教授
演讲摘要:
Liquid crystal elastomers, made of cross-linked polymeric chains with embedded mesogenic structures, combine orientational properties of liquid crystals with shear strength of solids. Their flexibility and sensitivity to chemical and physical signals comes close to that of biological tissues. Reshaping of nemato-elastic sheets or shells opens ways of creating a variety of forms that can be manipulated by imprinting a pattern, boundary anchoring, positioning of defects, and doping. Reversible local phase transitions causing repeated reshaping can be used to construct soft crawling and swimming robots with the gait and speed dependent on flexural rigidity and substrate friction. Still more flexible shape transformations unimpeded by area or volume conservation are possible in textiles actuated by of Janus fibers that combine stimuli-responsive and passive materials. Under certain conditions, alternative equilibrium states, one absolutely stable and the others metastable coexist, and their relative energy may flip its sign as the system parameters, such as the extension upon actuation, change.
演讲嘉宾简介:
Prof Leonid M. Pismen is an Emeritus Professor of the Department of Chemical Engineering, Technion-Israel Institute of Technology in Israel, Haifa. He got his Doctor Degree of Science of Physical Chemistry in the Karpov Physico-Chemical Institute, Moscow in 1963, and became Senior Research Associate, Institute of Electrochemistry of the USSR Academy of Sciences, Moscow, Theoretical Department, 1967-1973, and Department of Fuel Cells, 1973-1975. He was assigned as full professor in 1975 in the Department of Chemical Engineering, Technion-Israel Institute of Technology, J. & B. Naiman Professor of Fluid Mechanics since 1993, and Emeritus Professor since 2005. His researches focused in theory of transport processes and dynamics o nonlinear non- equilibrium systems, especially in physico-chemical and biological applications. He is the current editor of the European Physical Journal- Special Topics. He served as distinguished leading scientist in many Israel and Russian national projects. He has written 2 books with Springer and Oxford University Press respectively, and published over 100 journal papers in high impact journals.