图宾根大学（德国）张发军博士学术报告

主题    Kinetics and dynamics of arrested phase transition in          protein solution studied by USAXS-XPCS

活动时间   2019年09月19日 16:00-17:00

活动地址   南校区十友堂300室

主讲人     张发军博士，图宾根大学（德国）

主持人      张鹏 副教授

报告摘要：

      In protein and colloidal solutions, the interplay between liquid-liquid phase separation (LLPS) and glass formation can lead to a dynamic arrested state. While the kinetics of this process has been advanced in recent studies, little is known about the dynamics of domains approaching and in the arrested state. Here we report a study using X-ray photon correlation spectroscopy (XPCS) in USAXS mode with a tunable delay time. We use a mixture of bovine gamma-globulin (IgG) and polyethylene glycol (PEG) as a model system which features a LLPS upon quenching. By recording the two-time correlation functions in different time periods, we are able to follow the dynamics of domains (micrometer length scale) during coarsening and under arrest. The relaxation time as a function of aging time shows clearly two stages with an exponential increase in the early stage and a much slower power increase in the later stage, in good agreement with dynamics of aging and gelation process.

报告人简介：

       1997年毕业于南开大学化学系高分子物理专业。2002年于中科院长春应化所获博士学位。2002到2003期间在比利时鲁汶大学做博士后研究，之后在达姆施塔特工业大学从事为期两年的研究工作，获德国洪堡奖学金。2005年至今于德国图宾根大学应用物理研究所担任课题组长，2016年获得法国劳厄-朗之万研究所委员会成员资格。主要从事蛋白质结晶成核途径和生长动力学，抗蛋白质的静态和动态特性，功能化纳米粒子与蛋白质的相互作用等研究。目前的研究兴趣包括蛋白质、纳米粒子、胶体及薄膜的结构和相行为，小角散射在软物质物理的应用等。迄今在国际主流学术期刊发表学术论文80余篇（引用率超过2400次，H指数27），开展学术讲座84余次，担任J. Am. Chem. Soc.，ACS-nano等多个国际主流学术期刊审稿人。

欢迎广大师生踊跃参加！