由马兰戈尼不稳定引起的集体运动在表面张力自发振荡中的自发振荡
Yohko Yano1, Ryo Kubota1, Wolfgang Voegeli2
1Department of Physics, Kindai University, 3-4-1 Kowakae, Higashiosaka City, Osaka 577-8502, Japan.
Langmuir : the ACS journal of surfaces and colloids
|February 27, 2025
概括
表面张力自发振荡 (SOS) 是由于表面活性剂分子的周期性马兰戈尼流而发生的. 分子洞察力揭示这些振荡源于表面活性剂单层压力波动和分子方向变化.
科学领域:
- 物理化学 物理化学
- 表面科学是一门学科.
- 流体动力学 流体动力学
背景情况:
- 表面张力自发振荡 (SOS) 是一种在液体界面上观察到的微溶性表面活性剂的现象.
- 这种行为与短暂的马兰戈尼流动有关,由表面活性剂分子驱动.
研究的目的:
- 阐明了表面张力自发振荡背后的分子机制.
- 确定控制SOS特征的关键表面活性剂和单层性质.
主要方法:
- 在水面上对表面活性剂行为进行分子级观测.
- 对表面压力波动和分子方向的分析.
- 调查表面活性剂的扩散,可溶性,弹性和粘度的影响.
主要成果:
- SOS源于表面活性剂单层表面压力的周期性波动,这是由于分子方向的变化造成的.
- 通过增加表面活性剂的扩散和可溶性,可以实现更短的振荡周期.
- 振荡幅度通过放大马兰戈尼流动动量来增强,并受到单层弹性的影响.
结论:
- 这项研究为表面张力现象的自发振荡提供了分子层面的见解.
- 表面活性剂的扩散,可溶性,单层弹性和粘度是控制SOS的关键参数.
- 这些发现对理解由马兰戈尼效应驱动的复杂系统,包括细胞动力学,有意义.
相关概念视频
Surface Tension of Fluid
206
Surface tension is a fundamental property of fluids, occurring at the boundary between a liquid and a gas or between two immiscible liquids. This phenomenon arises from the cohesive forces between molecules at the fluid's surface, creating an effect similar to a stretched elastic membrane. Inside each fluid, molecules are equally attracted in all directions by neighboring molecules, but surface molecules experience a net inward force, resulting in surface tension.
Surface tension varies...
Surface tension varies...
206
Surface Tension and Surface Energy
1.3K
When a paint brush is immersed in water, the bristles wave freely inside the water. When it is taken out, the bristles stick together. The reason behind this effect is surface tension.
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
1.3K
Surface Tension, Capillary Action, and Viscosity
27.4K
Surface Tension
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
27.4K
Hydrostatic Pressure Force on a Curved Surface
1.2K
Hydrostatic pressure on curved surfaces is a fundamental concept in fluid mechanics with broad applications in the civil engineering field. When fluid is in contact with a curved surface, as in a reservoir, dam, or storage tank, it exerts pressure that varies in magnitude and direction along the curved surface. To assess the total hydrostatic force exerted by the fluid on a curved structure, engineers typically isolate the fluid volume adjacent to the surface and analyze the forces acting on...
1.2K
Navier–Stokes Equations
370
For incompressible Newtonian fluids, where density remains constant, stresses show a linear relationship with the deformation rate, defined by normal and shear stresses. Normal stresses depend on the pressure exerted on the fluid and the rate of deformation in specific directions, which determines how fluid flows under varying pressures. Shear stresses, on the other hand, act tangentially across fluid layers. They explain how adjacent fluid layers slide relative to one another, connecting...
370
Hydrostatic Pressure Force on a Plane Surface
236
When a plane surface is submerged in a fluid, hydrostatic forces develop on the surface due to the fluid's pressure. For horizontal surfaces, the pressure exerted by the fluid is uniform because the depth remains constant. The resultant force is determined by the pressure at the given depth multiplied by the area of the surface, and it acts through the centroid of the surface. For vertical surfaces, the pressure varies with depth, increasing as the distance from the fluid's free surface...
236


