Characterization of Hydrodynamics and Behavior of Viscoelasticity at the Nanoscale

纳米尺度的流体动力学和粘弹性行为表征

基本信息

批准号：
1660448
负责人：
Ryan Tung
金额：
$ 33.22万
依托单位：
Board of Regents, NSHE, obo University of Nevada, Reno
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2017
资助国家：
美国
起止时间：
2017-07-01 至 2021-06-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1660448&HistoricalAwards=false
关键词：
Characterization Hydrodynamics Behavior Viscoelasticity Nanoscale

项目摘要

The ability to measure physical properties of materials at very small scales is key to advancing scientific research and technological progress. Measurements that occur at the nanoscale, where the physical dimensions involved are on the order of one billionth of a meter, are of particular importance. The atomic force microscope (AFM) is one of the primary tools for making quantitative measurements of material properties at the nanoscale. However, there exist many physical phenomena at the nanoscale that prevent accurate quantitative measurements from being made, especially in liquid environments. This project aims to understand and fully characterize two such phenomena: fluid forces that arise at the nanoscale when the AFM is operated in liquid environments (hydrodynamics) and the underlying principles that govern the behavior of the material being interrogated (viscoelasticity). This project will enable quantitative measurements of material properties at the nanoscale in liquid environments on a variety of inorganic and biological materials. This will enable new and cutting-edge research in areas such as medicine, biology, and materials engineering. In addition, the project's educational plan will develop a hands-on, interactive, and portable learning platform that will expose K-12, undergraduate, and graduate students to AFM and the scientific principles used in its operation. The educational plan will engender further interest and retention in the STEM fields. The primary objective of this project is to understand the effect that complex sample viscoelasticity and hydrodynamic forces at the nanoscale have on the resonant behavior of measurement systems by developing mathematical and numerical models that capture and quantify these phenomena. These effects can be addressed through the lens of contact resonance (CR) spectroscopy AFM. The CR spectroscopy system is an ideal measurement platform to understand these phenomena because it is well understood in the absence of these effects and has the ability to interrogate both the hydrodynamic and viscoelastic parameter spaces of interest. The focus of this project is on accurately predicting the three-dimensional fluid-structure interactions present in CR spectroscopy systems, establishing material models for CR spectroscopy to account for biological and non-classical viscoelastic materials, and experimentally validating the fluid-structure interaction and viscoelastic models. The success of the project will enable accurate contact resonance based quantitative nanomechanical characterization of biological materials in liquid environments, which in turn will facilitate research in several key areas such as study of biomaterials and bio-polymers with applications to the medical community, study of nanomechanical structural changes in osteoarthritic bones, and study of dentin and tooth enamel.

在极小尺度上测量材料物理特性的能力是推进科学研究和技术进步的关键。在纳米尺度上进行的测量尤其重要，其中涉及的物理尺寸约为十亿分之一米。原子力显微镜（AFM）是在纳米尺度上定量测量材料特性的主要工具之一。然而，纳米尺度上存在许多物理现象，阻碍了精确的定量测量，特别是在液体环境中。该项目旨在理解并充分表征两种这样的现象：当原子力显微镜在液体环境中运行时在纳米尺度上产生的流体力（流体动力学）以及控制被研究材料行为的基本原理（粘弹性）。该项目将能够在液体环境中对各种无机和生物材料进行纳米级材料特性的定量测量。这将使医学、生物学和材料工程等领域的新的尖端研究成为可能。此外，该项目的教育计划将开发一个动手、互动和便携式学习平台，让 K-12、本科生和研究生接触 AFM 及其操作中使用的科学原理。该教育计划将进一步激发人们对 STEM 领域的兴趣和保留率。该项目的主要目标是通过开发捕获和量化这些现象的数学和数值模型，了解纳米级复杂样品粘弹性和流体动力对测量系统共振行为的影响。这些影响可以通过接触共振 (CR) 光谱 AFM 的透镜来解决。 CR 光谱系统是理解这些现象的理想测量平台，因为它在没有这些效应的情况下可以很好地理解，并且能够询问感兴趣的流体动力学和粘弹性参数空间。该项目的重点是准确预测 CR 光谱系统中存在的三维流固相互作用，建立 CR 光谱的材料模型以解释生物和非经典粘弹性材料，并通过实验验证流固相互作用和粘弹性模型。该项目的成功将使液体环境中生物材料基于接触共振的精确定量纳米力学表征成为可能，这反过来又将促进几个关键领域的研究，例如生物材料和生物聚合物的研究及其在医学界的应用、纳米力学的研究骨关节炎骨骼的结构变化以及牙本质和牙釉质的研究。