Molecular and Hybrid Simulations of Nanobubble Stability

纳米气泡稳定性的分子和混合模拟

• 批准号: 1403259
• 负责人: M Scott Shell
• 金额: $ 34.59万
• 依托单位: University of California-Santa Barbara
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1403259&HistoricalAwards=false
• 关键词: Molecular; Hybrid; Simulations; Nanobubble; Stability

PI: Shell, M. Scott Proposal Number: 1403259 Institution: University of California-Santa Barbara Title: Molecular and Hybrid Simulations of Nanobubble Stability This proposal addresses one of the foremost challenges in interfacial science, the critical issue of long-lived nanobubble stability on hydrophobic surfaces. A successful attack on this problem will have a significant impact on a range of emerging technologies that rely on the ability of stable nanobubbles to dramatically modify the properties of solid surfaces, including anti-fouling and surface cleaning techniques, transport in microfluidic devices, delivery of medical therapeutics, chemical processes involving biological or gas-liquid reactions, surface-induced crystallization, and catalysis. The PIs will also build on their record of involving students at multiple levels, including those from underrepresented groups (e.g., The Shell group has hosted two minority students from HBCU schools as summer research interns through UCSB's GRIP and SABRE programs), through different programs at UCSB (summer research opportunities for undergraduates and high school students, giving talks in events from minority associations and professional associations at UCSB). In particular, the PIs and graduate students will be involved with the SIMS summer program that involves top high school graduates. The main thrust of this proposal is to critically address several hypotheses for nanobubble stability, using state-of-the-art molecular and hybrid molecular continuum simulation methods that provide a complement to current experiments. The goal is to develop a thermodynamic picture of nanobubble stability because there is some evidence that the nanobubble may actually be thermodynamically stable. To that end, the PI will use molecular simulations to compute free energies of nanobubble formation as a function of bubble size, shape, composition, and solution conditions. The results will quantify the stabilities of the bubbles, and clarify whether and when they are associated with global or local (metastable) free energy minima. These free energies will also be compared with the macroscopic expectation (e.g., based on bulk surface tensions and solubilities) to assess the possible breakdown such arguments at the nanoscale. To achieve these goals, the proposal provides clearly formulated hypotheses, including both thermodynamic and dynamic transport mechanisms, that will be addressed.

PI：壳牌，M.Scott提案编号：1403259机构：加州大学圣巴巴拉分校标题：纳米气泡稳定性的分子和混合模拟这一提案解决了界面科学中最重要的挑战之一，即疏水表面上长寿命纳米气泡稳定性的关键问题。对这一问题的成功解决将对一系列新兴技术产生重大影响，这些技术依赖于稳定的纳米气泡的能力来显著改变固体表面的性质，包括防污染和表面清洁技术、微流控设备中的传输、医疗疗法的提供、涉及生物或气液反应的化学过程、表面诱导结晶和催化。PIs还将在其多层次学生参与的记录基础上再接再厉，包括那些来自代表性不足群体的学生(例如，壳牌集团通过UCSB的GRIP和SABRE项目接待了两名来自HBCU学校的少数族裔学生作为暑期研究实习生)，通过UCSB的不同项目(为本科生和高中生提供暑期研究机会，在UCSB少数族裔协会和专业协会的活动中发表演讲)。特别是，PI和研究生将参与SIMS暑期项目，该项目涉及顶尖高中毕业生。这项建议的主旨是使用最先进的分子和混合分子连续介质模拟方法来批判性地解决纳米气泡稳定性的几个假设，这些方法提供了对当前实验的补充。我们的目标是绘制纳米气泡稳定性的热力学图景，因为有一些证据表明，纳米气泡实际上可能是热力学稳定的。为此，PI将使用分子模拟来计算作为气泡大小、形状、组成和溶液条件的函数的纳米气泡形成的自由能。结果将量化气泡的稳定性，并澄清它们是否以及何时与全局或局部(亚稳态)自由能极小值有关。这些自由能也将与宏观预期(例如，基于整体表面张力和溶解度)进行比较，以评估这些论点在纳米尺度上可能崩溃的可能性。为了实现这些目标，该提案提供了明确表述的假设，包括热力学和动力学传输机制，这些假设将得到解决。