应我室低维物理与化学研究部曾长淦教授的邀请，3月15日，美国Brookhaven National Laboratory的Dr. Wei Kang前来我室进行学术交流与访问，并为我室师生做“Nanoscale Hydrodynamics and Its Application to Generation and Control of Nanojets: An Atomic View from Molecular Dynamics Simulations”的学术报告。
　　The dynamics of liquid structures is of fundamental interest in both theoretical investigations and industrial applications. The size of liquid structures in present-day applications is rapidly decreasing, even to the scale where macroscopic hydrodynamical equations may break down. Issues pertaining to the dynamics of nanoscale liquid systems, such as nanojets and nanobridges, are explored using both extensive molecular dynamics simulations and theoretical analyses. These investigations aim at extending hydrodynamic formulations to the nanoscale regime. As an application of the microscopic hydrodynamics, a heated-nozzle technique to generate and control nanojets is proposed. Both simulations and microscopic hydrodynamic modeling reveal the formation of a “virtual convergent nozzle”, which consists of a narrowing convergent liquid core within a growing evaporating sheath, by the nanojet itself inside the real nozzle. The diameter of the resulting ejected nanojet is much smaller than the diameter of the nozzle. By adjusting the temperature distribution of the real nozzle, the size and shape of the virtual nozzle are changed, which in turn changes the diameter and the direction of the ejected nanojet.