MRI: Acquisition of a Scanning Electron Microscope with In Situ Capabilities

摄影记录的是一个瞬间，而电影捕捉的是从一个瞬间到下一个瞬间的转变。 考虑一只小鸡从蛋中孵化出来，与一张蛋的照片和另一张小鸡的照片相比，一部电影的信息量要大得多。 在材料的研究中，我们感兴趣的是固体如何对各种环境和刺激做出反应。 在过去，我们通过制作许多重复的样品并在几个时间点停止变换来研究材料中的转变，以拍摄基本上静止的照片，然后试图将这些时间点之间的点连接起来。 这种方法既繁琐又缓慢，更不用说充满了关于遗漏信息的不确定性。 新仪器使研究人员能够刺激材料并同时记录它们的反应。 我们的成像方法检测的化学和拓扑特征比人类头发的厚度小500倍，并且还允许在这个长度尺度上进行样品操作。 对于设计新材料的非凡性能非常重要的刺激包括暴露于液体和气体，温度控制，电场和机械变形。 待研究的材料具有广泛的应用，包括燃料电池膜、高灵敏度化学传感器、柔性电子器件、工程涂层、组织工程结构表面和高效太阳能电池。 该仪器将被纳入我们非常成功的，专业人员配备的区域设施，向所有学术，工业和政府科学家和工程师开放。 新的扫描电子显微镜配备了一个独特的广泛的配件阵列，使高分辨率成像和纳米级操作的强大的原位实验，涉及控制刺激和相关的反应相结合。 原位能力包括样品的纳米级操作和暴露于流体、气体、电场、光、机械变形和温度。 该仪器实现的原位方法不仅比涉及多个仪器和暴露于空气的“进出”程序更清洁和更有效，而且还使理解纳米级基本过程的全新（尽管风险很高）举措成为可能。 要进行的实验远远超出了结构成像，同时将这一基本特征作为一个重要组成部分。 我们还将购买一台带数字成像/记录功能的光学显微镜;这将作为样品筛选和初步测量的“前端”，以确保SEM的最佳使用。 与七个部门相关的十七名教职员工代表了所有等级，他们在纳米科学的四个主题领域内为这种新仪器设想并计划了显着的实验：电响应材料（包括燃料电池膜，柔性电子和纳米电路），相变（包括超晶格，相分离和图案化），表面现象（包括润湿、细胞响应、气体吸附和自组装）和机械响应材料（包括硬材料、蛋白质和流体）。 用户群将成为发起新的合作、互动和培训/教育举措的协调中心。 该仪器将被纳入我们非常成功的，专业人员配备的区域设施，该设施向学术，工业和政府科学家和工程师开放。 为了鼓励地方文理学院，特别是高度选择性的女子学院布林莫尔学院的充分参与，我们将向这些机构的研究人员提供技术援助和机器使用。

Non-Technical AbstractPhotography records a moment in time, but movies capture the transformations that occur from one moment to the next. Consider a chick hatching from an egg and how much more informative a movie is as compared to one photograph of the egg and another of the chick. In the study of materials, we are interested in how solids respond to various environments and stimuli. In the past we have studied transitions in materials by making many duplicate samples and stopping the transformation at a few time points to take essentially still photographs and then attempting to connect the dots between these time points. This approach is tedious and slow, not to mention riddled with uncertainties about missed information. The new instrument enables researchers to stimulate materials and record their response at the same time. Our imaging method detects chemical and topological features 500 times smaller than the thickness of a human hair, and also allows for sample manipulation on this length scale. Stimuli that are important for designing extraordinary properties into a new material include exposure to liquids and gases, temperature control, electric fields, and mechanical deformation. The materials to be studied have a wide variety of applications including membranes for fuel cells, highly sensitive chemical sensors, flexible electronics, engineered coatings, structured surfaces for tissue engineering, and high-efficiency solar cells. The instrument will be incorporated into our highly successful, professionally staffed regional facility that is open to all academic, industrial, and governmental scientists and engineers. Technical AbstractThe new scanning electron microscope is equipped with a uniquely broad array of accessories to enable the combination of high-resolution imaging and nanoscale manipulation for powerful in situ experiments involving controlled stimuli and correlated response. In situ capabilities include nanoscale manipulation of specimens and exposure to fluids, gases, electrical fields, light, mechanical deformation, and temperature. The in situ approach enabled by this instrument is not only cleaner and more efficient than "in-and-out" procedures involving multiple instruments and exposure to air, it also makes possible entirely new, albeit high risk, initiatives to understand fundamental processes at the nanoscale. The experiments to be conducted go far beyond structural imaging, while incorporating this basic feature as an essential ingredient. We will also acquire an optical microscope with digital imaging/recording; this will serve as a "front end" for sample screening and preliminary measurements to inform and ensure the optimum use of the SEM. Seventeen faculty members associated with seven departments and representing all ranks have envisioned and planned remarkable experiments for this new instrument within four topical areas of nanoscale science: electrically responsive materials (including fuel cell membranes, flexible electronics, and nano circuitry), phase transitions (including superlattices, phase separation, and patterning), surface phenomena (including wetting, cell response, gas adsorption, and self-assembly), and mechanically responsive materials (including hard materials, proteins, and fluids). The user base will provide a focal point for initiating new collaborations, interactions and training/education initiatives. The instrument will be incorporated into our highly successful, professionally staffed regional facility that is open to academic, industrial, and governmental scientists and engineers. To encourage the full participation of local liberal arts colleges, particularly the highly selective women's college Bryn Mawr College, we will provide technical assistance and machine use to researchers from these institutions.