Combinatorial Multiscale Modeling and Simulation of DNA/Surface Interactions for Improved Microarray Design

CBET-0828433 Knotts知识产权。 这项工作的主要目标是开发一个改进的基本了解多孔陶瓷质子交换膜（PEM）的传输机制。几种类型的燃料电池的性能受到PEM性能的限制，这导致了大量的努力来开发新型的高性能PEM材料。目前用于这种应用的标准材料是磺化全氟化碳聚合物，例如Nafion®，其最大的缺点包括它们在高温（_80°C）下和/或当没有很好地水合时的差的性能。无机固体酸，包括一些纳米多孔陶瓷材料，是文献中报道的新型膜材料之一，并已在PI的实验室中证明，与Nafion®相比，具有更高的质子传导率和降低的燃料交叉通量。预计在这样的材料中的质子传输通过孔中的本体机制和沿着孔表面的表面机制进行，其中每一个的相对重要性强烈地依赖于膜性质，例如表面积和表面酸度以及环境参数，例如pH和温度。本文将系统地研究改性多孔氧化铝制备的PEMS中输运行为对这些关键变量的依赖性。膜的物理和化学表征将为基于分子动力学的模拟提供输入文件。这些模拟的结果将与传输行为的实验测量相结合，主要是从阻抗谱，以开发连续和等效电路模型，并确定相关的传输参数，如扩散率。更广泛的影响。 拟议的工作将培养研究生在两个领域的接口跨学科研究被广泛认为是至关重要的美国：燃料电池和纳米技术。虽然这项工作的直接应用是开发PEM燃料电池，用于从便携式电子产品的电池替代品到汽车发动机的应用，但它也将影响依赖于离子传导膜的各种传感器技术。该项目还将涉及路易斯安那理工大学和格兰布林州立大学（GSU）的本科生，通过两所大学联合任命的PI之一。在路易斯安那理工大学和GSU，一个HBCU的非裔美国学生的高比例（约15%的入学率），加上协调一致的外展工作，确保这个项目将对工程和科学中代表性不足的少数群体产生重大影响，除了加强路易斯安那理工大学和格兰布林之间的伙伴关系。此外，将本科生纳入研究活动将鼓励这些学生进入研究生院。这项工作将在EPSCOR州路易斯安那州进行，影响科学研究的地理多样性。PI与参与的研究生和本科生沿着将在国家会议上展示该项目的结果，此外还将参加路易斯安那理工大学正在进行的纳米技术研讨会系列。这些活动将有助于向广大受众传播成果，同时也为学生提供极其宝贵的学习经验和接触，特别是对本科生。

CBET-0828433KnottsIntellectual Merit. The primary goal of this work is to develop an improved fundamental understanding of the transport mechanisms in porous ceramic based proton exchange membranes (PEMs). The performance of several types of fuel cells is limited by PEM performance, which has lead to a plethora of efforts to develop novel, high performance PEM materials. Standard materials used for such applications today are sulfonated perfluorcarbon polymers such as Nafion® whose greatest drawbacks include their poor performance at high temperatures (_80°C) and/or when not well hydrated. Inorganic solid acids, including some nanoporous ceramic materials, are among the novel membrane materials reported in the literature and have been demonstrated in the PI's lab to have greater proton conductivity and reduced fuel crossover flux as compared to Nafion®. It is expected that proton transport in such materials proceeds through both a bulk mechanism in the pores and a surface mechanism along the pore surfaces, with the relative importance of each dependent strongly on membrane properties such as surface area and surface acidity as well as environmental parameters such as pH and temperature. This work will systematically investigate the dependence of transport behavior in PEMS fabricated from modified porous alumina on such key variables. Physical and chemical characterization of the membranes will inform input files for molecular dynamics based simulations. Results of these simulations will be coupled with experimental measurements of transport behavior, primarily from impedance spectroscopy, to develop continuum and equivalent circuit models and determine relevant transport parameters such as diffusivities. Broader Impacts. The proposed work will train graduate students in interdisciplinary research at the interface of two areas widely identified to be of critical importance to the United States: fuel cells and nanotechnology. While the immediate application of this work is to the development of PEM fuel cells for applications ranging from battery replacements for portable electronics to automotive engines, it will also impact a variety of sensor technologies which rely on ion conducting membranes. This project will also involve undergraduate students from both Louisiana Tech University and Grambling State University (GSU) through one of the PIs who has a joint appointment between the two universities. The a high percentage of African-American students for a non-HBCU (~15% of enrollment) at Louisiana Tech and at GSU, an HBCU, combined with concerted outreach efforts ensure that this project will have a significant impact on underrepresented minority groups in engineering and science in addition to enhancing partnerships between Louisiana Tech and Grambling. Additionally, the inclusion of undergraduate students in research activities will encourage these students to attend graduate school. This work will be performed in Louisiana, an EPSCOR state, impacting geographic diversity in scientific research. The PIs along with participating graduate and undergraduate students will present results from this project at national conferences in addition to participating in an ongoing nanotechnology seminar series at Louisiana Tech. These activities will serve both to disseminate results to a wide audience while also providing the students extremely valuable learning experiences and exposure, particularly for undergraduate students.