论文标题
部分可观测时空混沌系统的无模型预测
Sedimentation and Levitation of Catalytic Active Colloids
论文作者
论文摘要
通过将固体微粒的密度与周围的流体匹配，可以轻松地关闭胶体悬浮液的重力效应。通过研究具有可调浮力重量的催化微晶状体的运动，我们表明该策略不能用于主动胶体悬浮液。如果平均浮力重量减小，则由于与重力场的游泳速度对齐，观察到样品电池顶壁的明显积累。即使颗粒到达平壁时，重力扭矩仍然确定准二维活动运动的性质。我们的结果突出了重力在活动系统中的微妙作用。
Gravitational effects in colloidal suspensions can be easily turned off by matching the density of the solid microparticles with the one of the surrounding fluid. By studying the motion of catalytic microswimmers with tunable buoyant weight, we show that this strategy cannot be adopted for active colloidal suspensions. If the average buoyant weight decreases, pronounced accumulation at the top wall of a sample cell is observed due to a counter-alignment of the swimming velocity with the gravitational field. Even when the particles reach a flat wall, gravitational torques still determine the properties of the quasi two-dimensional active motion. Our results highlight the subtle role of gravity in active systems.
