NIRT: Nanoparticle-Environment Interfaces: Interactions in Natural Systems

0403732贝克尔最近的发展，表面分析，计算机模拟使用量子力学和经验的方法，并在电子显微镜先进的技术，现在允许准确的表征和建模之间的纳米粒子和他们的直接原子尺度的环境界面特性。 这些性质包括两个阶段之间的结构关系，在各自的主机，化学和附近的界面，电子转移机制在界面上，纳米粒子的磁有序，以及在近界面区域的主机矩阵的纳米材料的稳定性。 这些界面性质对纳米颗粒的反应性和环境行为有着重要的影响。 因此，如果只考虑其大小和结构，就无法理解它们在环境中的命运。 我们建议将这种新开发的实验和理论能力的组合应用于各种研究课题，这些研究课题共同关注纳米颗粒界面在自然系统中的重要作用，例如硫化物和氧化物表面上金属颗粒的形成及其并入散装，大气颗粒和地下水胶体中含金属纳米颗粒的运输，以及生物矿化过程。更广泛的影响：密歇根大学的这一新举措也得到了新的研究生和本科生课程开发的支持，以激发学生对这一领域的兴趣。我们正在开发环境地球化学，环境矿物学，矿物表面科学，计算方法，核材料和放射性废物管理的新课程。 来自不同学科的一些本科生和研究生，如矿物学，地质学，应用物理学，化学，核工程，材料科学和化学工程，预计将参与拟议的项目。 此外，我们计划在密歇根大学自然历史博物馆举办一个关于纳米粒子的公开展览。 该展览将强调纳米地质科学对公众感兴趣的不同领域的广泛适用性，例如医学（骨骼和牙齿生长），仿生材料的开发，金属开采和矿物加工的新方法，以及对环境有害的材料的释放和运输。 该博物馆定期参观，不仅是大学生，也是当地初中和高中的学生，以及公众。

0403732BeckerRecent developments in surface analysis, computer simulations using quantum mechanical and empirical methods, and advanced techniques in electron microscopy now allow the accurate characterization and modeling of interface properties between nanoparticles and their immediate atomic-scale environment. These properties encompass the structural relationships between both phases, the stability of nanomaterials in their respective hosts, the chemistry in and near the interface, electron transfer mechanisms across the interface, and magnetic ordering in the nanoparticle, as well as in the near-interface region of the host matrix. These interface properties have a critical influence on the reactivity and the environmental behavior of nanoparticles. Therefore, their fate in the environment cannot be understood if only size and structure are considered. We propose to apply this combination of newly-developed experimental and theoretical capabilities to a variety of research topics that collectively focus on the important role of nanoparticle interfaces in natural systems, such as the formation of metal particles on sulfide and oxide surfaces and their incorporation into the bulk, transport of metal-bearing nanoparticles in atmospheric particulates and groundwater colloids, and to biomineralization processes. Broader impact: This new initiative at the University of Michigan is also supported by the development of new graduate and undergraduate courses to stimulate student interest in this field. We are in the process of developing new courses in environmental geochemistry, environmental mineralogy, mineral surface science, computational methods, nuclear materials, and radioactive waste management. A number of undergraduate and graduate students from different disciplines, such as mineralogy, geology, applied physics, chemistry, nuclear engineering, materials science, and chemical engineering are expected to be involved in the projects proposed. In addition, we plan to develop a public exhibition on nanoparticles in the Museum of Natural History at the University of Michigan. The exhibit will emphasize the broad applicability of nanogeoscience to diverse areas of great public interest, such as medicine (bone and tooth growth), development of geomimetic materials, new methods for metal exploitation and mineral processing, and release and transport of environmentally hazardous materials. The museum is regularly visited, not only by university students, but also by students from the local middle and high schools, and by the general public.