法拉第波在阴性液晶上,以及它与马兰戈尼对流的合,关于热相过渡的热相过渡
O Vázquez-Rodriguez1, M Hernández-Contreras2
1Facultad de Ciencias en Física y Matemáticas Universidad Autónoma de Chiapas, 29050 Tuxtla Gutierrez, Chiapas, México.
Physical review. E
|December 20, 2023
概括
法拉第波在液晶中使用水力动力学理论证明了法拉第波. 马兰戈尼对流会在相位过渡温度下导致波特征的突然变化.
科学领域:
- 流体动力学 流体动力学
- 液晶物理学 液晶物理
- 非线性现象是一种非线性现象.
背景情况:
- 法拉第波是由垂直振荡的流体形成的静止波.
- 液晶表现出独特的特性,由于它们的异构分子结构.
- 马兰戈尼对流是由表面张力梯度引起的,通常是温度引起的.
研究的目的:
- 从理论上证明法拉第波在液晶流体中的存在.
- 为了研究马兰戈尼对流动对液晶中法拉第波的影响.
- 用实验材料参数验证理论预测.
主要方法:
- 线性水力动力学理论应用于液晶系统.
- 使用已知的N-(4-甲基乙烯) -4-丁林的材料参数.
- 在不稳定性开始时分析临界波数和驱动加速.
主要成果:
- 理论证实了液晶中法拉第波的产生.
- 确定不稳定性开始的关键参数.
- 观察到波特征的突然变化,这是由于在等离子体-水体相位过渡时的马兰戈尼对流.
- 马兰戈尼数与过渡附近的温度有明显的变化.
结论:
- 线性水力动力学理论准确地预测了液晶中的法拉第波.
- 马兰戈尼对流显著影响法拉第波特征在相位过渡附近.
- 这项研究为了解液晶中的流体动力学提供了一个框架.
相关概念视频
Phase Transitions: Vaporization and Condensation
17.6K
The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize (convert into vapor). The process is called vaporization—a surface phenomenon. Vaporization occurs when the thermal motion of the molecules overcome the intermolecular forces, and the molecules (at the surface) escape into the gaseous state. When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase...
17.6K
Phase Transitions: Melting and Freezing
12.4K
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...
12.4K
Magnetic Field due to Moving Charges
8.7K
A stationary charge creates and interacts with the electric field, while a moving charge creates a magnetic field.
Consider a point charge moving with a constant velocity. Like the electric field, the magnetic field at any point is directly proportional to the magnitude of the charge and inversely proportional to the square of the distance between the source point and the field point. However, unlike the electric field, the magnetic field is always perpendicular to the plane containing the line...
Consider a point charge moving with a constant velocity. Like the electric field, the magnetic field at any point is directly proportional to the magnitude of the charge and inversely proportional to the square of the distance between the source point and the field point. However, unlike the electric field, the magnetic field is always perpendicular to the plane containing the line...
8.7K
Dielectric Polarization in a Capacitor
4.7K
The presence of a dielectric medium in a capacitor not only changes the voltage and capacitance but also affects the electric field. In general, dielectrics can be of two types: polar and nonpolar. In a polar dielectric, the positive and negative charges in the molecules are separated by a distance and hence have a permanent dipole moment. In contrast, no such charge separation exists in a nonpolar dielectric, however the nonpolar molecules get polarized in the presence of an external electric...
4.7K
Phase Transitions
19.1K
Whether solid, liquid, or gas, a substance's state depends on the order and arrangement of its particles (atoms, molecules, or ions). Particles in the solid pack closely together, generally in a pattern. The particles vibrate about their fixed positions but do not move or squeeze past their neighbors. In liquids, although the particles are closely spaced, they are randomly arranged. The position of the particles are not fixed—that is, they are free to move past their neighbors to...
19.1K
Standing Waves in a Cavity
931
A household microwave and lasers are examples of standing electromagnetic waves in a cavity. When two conducting metal plates are placed parallel at the nodal planes, it creates a cavity where standing waves are formed. The cavity between the two planes is analogous to a stretched string held at the points x = 0 and x = L. Here, the distance 'L' between the two planes must be an integer multiple of half of the wavelength. The wavelengths that satisfy this condition are given by:
931


