Collaborative Research: ISS: Microgravity enabled studies of particle adsorption dynamics at fluid interfaces

合作研究：国际空间站：微重力支持流体界面颗粒吸附动力学的研究

• 批准号: 2224413
• 负责人: Michael Bevan
• 金额: $ 27万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-15 至 2026-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2224413&HistoricalAwards=false
• 关键词: Collaborative; Research; ISS; Microgravity; enabled

Particle-laden droplets have received attention for their applications in emulsions, catalysis, sensing, optical materials, as well as environmental remediation. An important step in creating particle-laden fluid interfaces is the transport and attachment (adsorption) of the particles to a fluid droplet. Unfortunately, it is challenging to study directly the attachment process on Earth with the competing effects of sedimentation (gravitational settling) of the particles dispersed in the bulk of the fluid. In other words, there is competition between particles attaching to a fluid interface and settling because of gravity. To alleviate the effect of gravity, this award aims to study adsorption of particles to fluid interfaces under microgravity in the international space station. The project will elucidate the critical steps of how particles attach to droplets in the absence of sedimentation. Findings from this award will lead to engineering strategies to optimize the design of materials that rely on particle-laden interfaces. From a technological standpoint, the knowledge gained will be directly applicable to emerging technologies in additive manufacturing and optical materials to impact life on Earth. The stability of particle-stabilized emulsions strongly depends on the particle coverage at the interface. Kinetic limitations during particle adsorption limit Pickering emulsions from reaching their full technological potential. This award aims to advance our understanding of particle adsorption at interfaces by developing: 1) fundamental knowledge in structure-property (surface pressure-area fraction) relationships at fluid interfaces, 2) an understanding of the transition from fluid to glassy (sluggish) dynamics at fluid interfaces, and 3) a validated model describing diffusion-limited adsorption. This award aims at understanding the mechanisms limiting the adsorption of particles to fluid interface by conducting experiments in microgravity. Microgravity experiments are necessary and allow to investigate adsorption dynamic in the absence of sedimentation. The time scale for gradient diffusion to a fluid interface can be of order of hours, making parabolic flights not a realistic option to avoid gravitational effects. While key experiments will be conducted under microgravity, the scientific and technological impacts of the work will benefit life on Earth. Findings will benefit any processes involving particles adsorption to fluid interfaces including in manufacturing, consumer products, flotation, oil recovery, and environmental remediation.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

充满颗粒的液滴因其在乳液，催化，传感，光学材料以及环境补救中的应用而受到关注。创建载有颗粒的流体界面的重要步骤是颗粒到流体液滴的传输和附着（吸附）。不幸的是，直接研究地球上的依恋过程与分散在大部分液体中的颗粒的竞争作用（重力沉降）的竞争作用是一项挑战。换句话说，由于重力，附着在流体界面上的颗粒与沉降之间存在竞争。为了减轻重力的影响，该奖项旨在研究国际空间站微重力下的流体接口的吸附。该项目将阐明在没有沉积物的情况下颗粒附着在液滴上的关键步骤。该奖项的发现将导致工程策略，以优化依赖含有颗粒界面的材料的设计。从技术的角度来看，获得的知识将直接适用于添加剂制造和光学材料中的新兴技术，以影响地球上的生命。粒度乳液的稳定性在很大程度上取决于界面处的粒子覆盖范围。颗粒吸附限制乳液的动力学限制无法达到其全部技术潜力。该奖项旨在通过开发：1）在流体界面上的结构 - 特性（表面压力面积分数）关系的基本知识来促进我们对界面上粒子吸附的理解，2）对从流体到玻璃（Sluggish）流体界面的过渡（Sluggish）在流体界面上的过渡，以及3）一个有验证的模型描述扩散量的ADSORPERTIPT ADSORPTIENT。该奖项旨在了解通过进行微重力实验来限制颗粒吸附到流体界面的机制。微重力实验是必要的，并允许在没有沉降的情况下研究吸附动态。梯度扩散到流体界面的时间尺度可能是小时的阶数，这使抛物线飞行不是避免重力效应的现实选择。尽管将在微重力下进行关键实验，但工作的科学和技术影响将使地球上的生命受益。调查结果将使涉及颗粒吸附到流体界面的过程中受益，包括制造业，消费产品，浮选，石油回收和环境补救。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛的审查标准通过评估来通过评估来获得支持的。