Collaborative Research: Reversible and Triggerable Self-Assembly of Photoresponsive Catanionic Vesicles

当一种液体在固体表面上取代另一种液体时，它与固体的夹角称为动态接触角。它提供了对固体上的力的测量，并用于了解工艺可行性的限制。当被置换的流体被夹带时，这个极限就出现了。这些特征在涂布流动中可以观察到，例如在照相胶片的制作中，在用另一种流体取代原油的过程中，在用另一种流体取代原油的过程中，以及在液体池或连续形式的液体从一个区域移动到另一个区域的微电子设备中。知识价值。在这里提出的建模研究中，P.I.将近似于接触线区域，即该动态接触角的液体楔块取代了先前成功模型中的第二种流体。将动量平衡方程精确地求解到Re、雷诺数的阶，并计算整个系统的粘性耗散。这等于完成地面功的速率，再次遵循早期成功的模型。最终解决方案将以角作为Ca，（毛细管数）和Re的函数的形式出现。新的特征是(a)将建立大角度的相关性，(b)将建立液-液系统的相关性，(c)夹带的开始角度= 180°（或0°），以及它可能因系统几何形状而异的原因将建立。后退接触线夹带的一个较简单的问题也将在另一种表述下单独研究。私家侦探还将进行实验，以获得上述系统和操作范围的实验数据。更广泛的影响。这些结果将允许人们设置操作窗口，其中涂层工艺是可行的，假设该工艺在夹带时失败。动态接触角还提供了系统中力平衡的估计。因此，上述相关性为处于新兴技术前沿的系统中的合理过程设计提供了非常好的基础。基本理论是直截了当的，所取得的进展也可以被纳入到界面现象或传输的教学中，这两门课程都是由pi以技术选修课的形式教授的。本实验室将招收本科生和研究生。

CBET-0829209 LeeWhen a liquid displaces another fluid on a solid surface, the angle that it subtends with the solid is called the dynamic contact angle. It provides a measure of the force on the solid and is used to understand the limits of the feasibility of the process. This limit arises when the displaced fluid gets entrained. These features are observed in coating flows as in making of photographic films, in displacement of one fluid by another in a pore which is of importance in the recovery of crude petroleum oil by displacement with another fluid, and in microelectronic devices where pools of liquid or liquid in a continuous form is moved from one region to another. Intellectual Merit. In the modeling studies proposed here, the P.I. will approximate the contact line region a liquid wedge of this dynamic contact angle displacing a second fluid following earlier successful models. The momentum balance equations will be solved correct to order of Re,(Reynolds number) and viscous dissipation will be calculated for the whole system. This is equated to the rate of surface work done, again following earlier successful model. Final solution will be in the form of the angle as a function of Ca, (capillary number) and Re. The novel features are (a) correlations at large the angle will be established, (b) correlations for liquid-liquid system will be established (c) the onset of entrainment at the angle = 180° (or at 0°), and the reasons why it may vary from one system geometry to another will be established. A simpler problem of entrainment in a receding contact line will also be studied separately under a different formulation. The P.I. will also perform experiments to obtain experimental data for the above systems and ranges of operation. Broader Impact. These results would allow one to set windows of operation where a coating process is feasible, assuming that the process fails at entrainment. Dynamic contact angles also provide estimates of force balances in the systems. Consequently, the above correlations provide a very good basis for sound process design in systems that are in the cutting edge in emerging technologies. The basic theory is straightforward and the progress that would be made can also be incorporated into teaching either in a course on interfacial phenomena or transport, both of which are taught by the P.I. in form of technical electives. Both undergraduates and graduate students will be employed in the laboratory.