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Prof. Xiang-Jun Xing
Institute of Natural Sciences and Department of Physics
Shanghai Jiao Tong University |
Abstract: Recent experiments on vesicles formed from block copolymers with liquid-crystalline side-chains reveal a rich variety of vesicle morphologies. The additional internal order (\structure") developed by these self-assembled block copolymer vesicles can lead to signicantly deformed vesicles as a result of the delicate interplay between two-dimensional ordering and vesicle shape. The inevitable topological defects in structured vesicles of spherical topology also play an essential role in controlling the final vesicle morphology. Here we develop a minimal theoretical model for the morphology of the membrane structure with internal nematic/smectic order. Using both analytic and numerical approaches, we show that the possible low free energy morphologies include nano-size cylindrical micelles (nano-fibers), faceted tetrahedral vesicles, and ellipsoidal vesicles, as well as cylindrical vesicles. The tetrahedral vesicle is a particularly fascinating example of a faceted liquid-crystalline membrane. Faceted liquid vesicles may lead to the design of supra-molecular structures with tetrahedral symmetry and new classes of nano-carriers.
报告人简介:邢向军,上海交通大学理学院(物理系)研究员。1993年毕业于南京大学数学系,获学士学位;1996年获南京大学物理学硕士学位。2003年获美国科罗拉多大学(University of Colorado at Boulder)物理博士学位。2003年至2005年在伊利诺大学(UIUC)做博士后研究工作。2005年至2010年在美国雪城大学(Syracuse University) 物理系任助理教授职位。2010年起在上海交大物理系和自然科学研究员任特聘教授。研究方向为软凝聚态理论,统计物理。具体包括聚合物,胶体,液晶,橡胶类材料以及膜的弹性理论,以及随机堆积系统的统计性质等。
Date&Time: December 28, 2012 (Friday), 15:30–16:30
Location: 606 Conference Room