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分子スケールの液体の濡れや流れのシミュレーションによる解析で先端的な研究をされている Donatas Surblys氏（理化学研究所） Laurent Joly氏（フランス，Lyon大学） のお二人をお招きして，下記2件のセミナーを開催いたします．皆様のご参加をお待ち致しております． ----------講演1---------- 講師: Donatas Surblys 氏 (Postdoctoral Researcher, 理化学研究所) 題目: Molecular dynamics study of the effect of surface polarity on wettability 日時: 2016年8月31日(水) 13:30～15:00(予定) 場所: M1棟3階 311講義室 概要: The behavior of liquid, and especially droplets, on a solid surface has long been a topic of interest both as basic science and in various engineering fields. Wettability, the ability of a liquid to spread over a solid surface, is of particular interest due to its considerable practical importance in industries such as high resolution printing and semiconductor production. The work of solid-liquid adhesion is one of the fundamental properties that determines surface wettability, but has long been difficult to obtain both experimentally and by computer simulation. In this talk I will present a molecular dynamics method based on thermodynamic integration which allows to easily calculate the work of adhesion even when there are long-range Coulomb forces acting between solid and liquid regions, which were traditionally difficult to treat. This method is applied to various water-silica systems to gauge the effect of surface polarity on wettability and a generic relation between solid-liquid energy and work of adhesion is demonstrated. ----------講演2---------- 講師: Laurent Joly 氏 (Assistant professor, Institut Lumière Matière, Université Lyon, France) 題目: Energy conversion in nanofluidic devices: the crucial role of interfacial hydrodynamics 日時: 2016年9月1日(木)，9:30～11:00(予定) 場所: M1棟3階 311講義室（予定，確定次第HPで告知） 概要: Water desalination and sustainable energy harvesting are among the greatest challenges of our society, and nanofluidics offers promising solutions to address them. Nanofluidic energy conversion systems rely on electrokinetic (EK) effects, which couple different types of transport (hydrodynamic, electric, ionic, thermal...) at interfaces. EK effects are sensitive to the molecular detail of interfaces, and should thus depend on their physical chemistry. In particular, it has recently been put forward that EK effects are highly sensitive to interfacial hydrodynamics, and can for instance be amplified by liquid/solid slip [1]. In this talk I will discuss some of our recent work in which we have been using molecular dynamics simulations to better understand how the nanoscale dynamics of interfaces affects EK effects. This will include work focused on anomalous EK effects at liquid/vapor interfaces covered with ionic surfactants [2,3], electro-osmotic flows induced by biological lipidic membranes [4], and diffusio-osmotic flows in aqueous solutions of neutral solutes such as ethanol [5]. Finally, I will discuss how EK effects can be further controlled through interfacial reactivity [6], paving the way toward efficient nanofluidic energy conversion devices. [1] L. Joly, C. Ybert, E. Trizac, L. Bocquet: “Hydrodynamics within the electric double layer on slipping surfaces”, Phys. Rev. Lett. 93, 257805 (2004) [2] L. Joly, F. Detcheverry, A.-L. Biance: “Anomalous zeta potential in foam films”, Phys. Rev. Lett. 113, 088301 (2014) [3] A. Barbosa de Lima, L. Joly: “Molecular modeling of electro-osmosis at the liquid-vapor interface”, in preparation [4] S. Vilov, L. Joly, C. Loison: “Electrokinetics nearby a neutral lipidic membrane: comparison of continuum hydrodynamic models with molecular dynamics simulations”, in preparation [5] C. Lee, C. Cottin-Bizonne, R. Fulcrand, L. Joly, C. Ybert: “Nano-scale dynamics vs surface interactions: what dictates osmotic transport?”, submitted [6] L. Joly, G. Tocci, S. Merabia, A. Michaelides: “Strong coupling between nanofluidic transport and interfacial chemistry: how defect reactivity controls liquid-solid friction through hydrogen bonding”, J. Phys. Chem. Lett. 7, 1381 (2016)