CAREER: Nuclear Magnetic Resonance Microscopy Studies of Microfluidic and Porous Media Transport

职业：微流体和多孔介质传输的核磁共振显微镜研究

• 批准号: 0348076
• 负责人: Joseph Seymour
• 金额: $ 40万
• 依托单位: Montana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-04-01 至 2010-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0348076&HistoricalAwards=false
• 关键词: CAREER; Nuclear; Magnetic; Resonance; Microscopy

AbstractCTS-0348076J. Seymour, Montana State UniversityThe modeling of colloidal suspension transport in small channels is relevant to mixing in microfluidic devices for sensor technology, to the sorption of microbial bacteria in medical implant infections and earth formation bioremediation and to filtration devices and other porous media used for separations. Improved models of such systems could have a broad impact to society through design of medical sensors and filtration devices and environmental bioremediation strategies. The hypothesis of the research is that the nonequilibrium microstructure and dynamics of colloid suspension flows in micro-channels, capillary networks and porous media can be characterized using NMR microscopy. Dynamics of colloidal particles in channels of the order of 100 micrometers are relevant to microfluidic applications such as biosensors and 'lab on a chip' systems and are the basis of colloid transport in the network of pore spaces in porous media. NMR microscopy methods allow noninvasive measurement of time and length scale dependent displacements within opaque systems such as colloidal suspensions and provide unique data for testing of conceptual and numerical models. The research will begin with rectilinear flows of model spherical colloidal particles in a Couette geometry and progress to single capillaries, capillary bifurcations, capillary networks and porous media. Cellular suspensions of blood and microbial bacteria will be studied in these same flow systems to test the relevance of hard sphere colloid models to transport of natural systems.The objectives of the research are:1) To test computer models of colloid rheology by measurement of the microstructure, velocity distribution and diffusion tensor of model and cellular suspensions in Couette flows using NMR microscopy methods2) To measure the concentration distribution, velocity and hydrodynamic dispersion tensor of model and cellular colloid suspension flows in straight capillary microchannels, capillary microchannel bifurcations and networks in order to model mixing processes relevant to microfluidic and physiological flows and incorporate rheological data from objective 1) into such models3) To provide the first non-invasive measurements of concentration distribution, velocity and hydrodynamic dispersion in model and cellular colloidal suspension flows through porous media in order to incorporate microhydrodynamics into models for colloid deposition and transport in porous media4) To integrate multiphase transport in microfluidic devices and porous media into the undergraduate and graduate curricula using NMR microscopy flow visualization.These objectives will provide quantification of the microscale hydrodynamics influencing colloidrheology, mixing in microfluidic flows and colloid transport and deposition in porous media. The significance of this work lies in the potential for new insight into existing theory and experiments by providing data on opaque colloidal dispersion dynamics not available by other techniques.The prevalence of colloid transport issues in industrial, biomedical and environmental applications and the computer and digitizer upgrades of the campus NMR facility DRX250 that will benefit all users, gives the project broader impacts to society.The exploration of the lower resolution limits of NMR microscopy for measurement ofnonequilibrium transport coefficients in microfluidic transport, where these methods have yet to be applied, will provide a key link between prior data on macroscopic system behavior andmicroscale dynamics, lending insight into issues of scale down engineering in microfluidics. The flow visualization aspects of NMR microscopy will be used to integrate concepts from colloidrheology with mixing in microfluidics and deposition in porous media into the undergraduate curricula, providing a connection between core concepts in transport phenomena like Taylor-Aris dispersion and advanced concepts such as non deterministic chaotic mixing.

摘要CTS-0348076 J。Seymour，Montana State University小通道中胶体悬浮液运输的建模与传感器技术的微流体装置中的混合、医学植入感染和地球形成生物修复中微生物细菌的吸附以及用于分离的过滤装置和其他多孔介质有关。这种系统的改进模型可以通过设计医疗传感器和过滤装置以及环境生物修复战略对社会产生广泛的影响。研究假设：胶体悬浮液在微通道、毛细网络和多孔介质中流动的非平衡微观结构和动力学可以用核磁共振显微镜表征。胶体颗粒在100微米量级的通道中的动力学与微流体应用如生物传感器和“芯片实验室”系统相关，并且是多孔介质中孔隙空间网络中胶体传输的基础。NMR显微镜方法允许非侵入性测量的时间和长度尺度相关的位移不透明的系统，如胶体悬浮液，并提供独特的数据测试的概念和数值模型。研究将开始与Couette几何形状的模型球形胶体颗粒的直线流动，并进展到单毛细管，毛细管分叉，毛细管网络和多孔介质。将在这些相同的流动系统中研究血液和微生物细菌的细胞悬浮液，以测试硬球胶体模型与自然系统传输的相关性。研究的目的是：1）通过使用NMR显微镜方法测量Couette流中模型和细胞悬浮液的微观结构、速度分布和扩散张量来测试胶体流变学的计算机模型2）测量直毛细管微通道中模型和细胞胶体悬浮液流的浓度分布、速度和流体动力学扩散张量，毛细管微通道分叉和网络，以便对与微流体和生理流动相关的混合过程建模，并将来自目标1）的流变学数据结合到这样的模型中3）为了提供浓度分布的第一次非侵入性测量，速度和流体动力学分散在模型和细胞胶体悬浮液流经多孔介质，以纳入微流体力学，多孔介质中胶体沉积和输运模型4）将微流体装置和多孔介质中的多相输运结合到利用NMR显微流动可视化的本科和研究生课程中，这些目标将提供影响胶体流变学、微流体流动中的混合以及多孔介质中胶体输运和沉积的微尺度流体动力学的量化。这项工作的意义在于通过提供其他技术无法获得的不透明胶体分散动力学数据，对现有理论和实验进行新的洞察。胶体传输问题在工业、生物医学和环境应用中的普遍性，以及校园NMR设备DRX 250的计算机和数字化仪升级，这将使所有用户受益，为该项目带来了更广泛的社会影响。探索核磁共振显微镜测量微流体传输中非平衡传输系数的分辨率下限，这些方法尚未应用，将提供宏观系统行为和微尺度动力学的先前数据之间的关键联系，从而深入了解微流体中的按比例缩小工程问题。NMR显微镜的流动可视化方面将用于将胶体流变学的概念与微流体中的混合和多孔介质中的沉积整合到本科课程中，提供了传输现象中的核心概念之间的连接，如泰勒-阿里斯分散和先进的概念，如非确定性混沌混合。