MRI: Development of a Compact Instrument for Measurements of Retention forces in a Controlled Environment

PI: Tadmor， RafaelProposal: 1428398MRI：一种用于在受控环境中测量保持力的紧凑型仪器的开发意义本提案的主要目标是开发一种新的离心粘附平衡（CAB）模型，该模型包括温度和湿度控制在一个紧凑型单元中，以便评估它们对液滴保持力的影响，并允许从CAB测量中系统地研究表面稳健性。这将使CAB适用于新系统，并大大提高其他研究人员的使用。液滴在表面的问题具有广泛的工业意义，涉及隐形眼镜、眼药水、吸入性药物和化妆品行业，以及可变形颗粒和纳米技术等现象。粗糙度在自然界许多表面的润湿性中起着至关重要的作用，可以用来控制表面的润湿性。在某些应用中，将液滴保留在表面上是有用的，例如在水基除草剂的情况下，或在热交换器表面，或试图保留泄漏物时。在其他应用中，希望液滴从表面上滑落，如从多孔岩石和自清洁表面中采油。对自清洁表面的兴趣是由制造卫星天线、太阳能板、光伏、外部建筑玻璃和温室的这种表面的愿望驱动的。技术描述：由Shanahan和de-Gennes提出并使用CAB实验证实的理论表明，与法向力和侧向力相关的中心参数是与固体表面最外层对应的剪切模量，这里称为界面模量。该特性描述了其表面弹性，使其最外层与与之接触的液滴一致，并且预计是温度和相对湿度的强烈函数。新的CAB将实现温度和湿度控制，从而允许测量，从而了解这些参数对不同系统的影响。科学也缺乏对纳米结构表面的物理学的理解，以及它与这种固体结构与上面的液体相适应的能力的关系。这些系统对湿度和温度特别敏感。生物表面对温度和湿度也极为敏感。拟议的文书将能够系统地研究这些系统。

PI: Tadmor, RafaelProposal: 1428398MRI: Development of a Compact Instrument for Measurements of Retention forces in a Controlled EnvironmentSignificance The main goal of this proposal is to develop a new Centrifugal Adhesion Balance (CAB) model that includes temperature and humidity controls in one compact unit to enable evaluating their effect on drop retention force, and allow a systematic study of surface robustness from CAB measurements. This will make the CAB applicable to new systems, and significantly enhance its use by other researchers. The problem of drops on surfaces has wide industrial implications related to contact lenses, eye drops, inhalation drugs, and cosmetic industry as well as implication in phenomena like deformable particles and nanotechnology. Roughness plays a crucial role in wetting properties of many surfaces in nature, and can be used to control the wettability of a surface. In some applications, it is useful to retain the drops on the surfaces, for example in the case of water-based herbicides, or in heat exchanger surface, or when trying to retain a spill. In other applications, it is desired that the drops slide off the surfaces as in oil extraction from porous rock and self-cleaning surfaces. The interest in self-cleaning surfaces is being driven by the desire to fabricate such surfaces for satellite dishes, solar energy panels, photovoltaics, exterior architectural glass, and green houses.Technical DescriptionTheories initiated by Shanahan and de-Gennes and confirmed experimentally using the CAB show that a central parameter in relating normal to lateral forces is a shear modulus that corresponds just to the outmost layer of the solid surface, termed here interfacial modulus, . This property describes the surface resilience to conform its outmost layer to a liquid drop in contact with it, and is expected to be a strong function of the temperature and relative humidity. The new CAB will enable temperature and humidity controls and thereby allow measurements that lead to understanding of the influence of these parameters on for different systems. Science is also lacking in understanding of the physics related to nano-structured surfaces, and its relation to the ability of such solid structures to conform to the liquid above them. These systems are particularly sensitive to humidity and temperature. Biological surfaces are also extremely sensitive to temperature and humidity. The proposed instrument will enable systematic study of these systems.