Dynamics of a camphoric acid boat at the air-water interface
Dynamics of a camphoric acid boat at the air-water interface
复制标题
DOI：
10.1016/j.physleta.2018.02.026
复制
发表时间：
2018-05-03
影响因子：
2.6
通讯作者：
Bandi, M. M.
中科院分区：
文献类型：
--
作者：
Akella, V. S.;Singh, Dhiraj K.;Bandi, M. M.
我们报道了一种琼脂糖凝胶片负载樟脑酸（c-boat）的实验，该凝胶片在水面表面张力梯度的作用下自发运动。我们观察到c-boat运动的三种不同模式：谐波模式（c-boat速度随时间呈正弦振荡），稳定模式（c-boat保持恒定速度）和间歇模式（c-boat在速度突然跳跃之间保持接近零的速度）。虽然这三种模式之前已经在不同的系统中分别报道过，但从琼脂糖凝胶基质中控制释放樟脑酸（CA）允许在同一系统中观察到所有三种模式。这三种模式是驱动（表面张力梯度）和作用在c-boat上的阻力之间竞争的结果。此外，我们认为存在两个时间尺度对应于CA的扩散和船的运动，这两个时间尺度的不匹配导致了船运动的三种模式。我们用十二烷基硫酸钠（SDS）改变空气-水界面张力，重现了所有的运动模式。(C) 2018 Elsevier B.V.版权所有
We report experiments on an agarose gel tablet loaded with camphoric acid (c-boat) spontaneously set into motion by surface tension gradients on the water surface. We observe three distinct modes of c-boat motion: harmonic mode where the c-boat speed oscillates sinusoidally in time, a steady mode where the c-boat maintains constant speed, and an intermittent mode where the c-boat maintains near-zero speed between sudden jumps in speed. Whereas all three modes have been separately reported before in different systems, controlled release of Camphoric Acid (CA) from the agarose gel matrix allowed the observation of all the three modes in the same system. These three modes are a result of a competition between the driving (surface tension gradients) and drag forces acting on the c-boat. Moreover we suggest that there exist two time scales corresponding to spreading of CA and boat motion and the mismatch of these two time scales give rise to the three modes in boat motion. We reproduced all the modes of motion by varying the air-water interfacial tension using Sodium Dodecyl Sulfate (SDS). (C) 2018 Elsevier B.V. All rights reserved.