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。想想一只小鸡从蛋里孵出来，和一张鸡蛋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对各种环境和刺激的反应。在过去，我们通过制作许多重复样本并在几个时间点停止转换来研究材料的过渡，以拍摄基本上静止的照片，然后尝试将这些时间点之间的点连接起来。这种方法既乏味又缓慢，更不要说还充满了遗漏信息的不确定性。这种新仪器使研究人员能够同时刺激材料并记录它们的反应。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。对于设计新材料的特殊性能来说，重要的刺激因素包括暴露在液体和气体中、温度控制、电场和机械变形。所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、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组成的区域设施，向所有学术，工业和政府科学家和工程师开放。技术摘要：新型扫描电子显微镜配备了一系列独特的配件，可以将高分辨率成像和纳米级操作相结合，用于涉及受控刺激和相关反应的强大原位实验。现场能力包括纳米级的标本操作和暴露在流体、气体、电场、光、机械变形和温度下。该仪器实现的原位方法不仅比涉及多个仪器和暴露在空气中的“进出”过程更清洁、更高效，而且还使理解纳米级基本过程的全新举措成为可能，尽管风险很高。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基本成分纳入其中。我们还将购置一台带有数码成像/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”，以告知并确保SEM的最佳使用。来自7个院系的17位教职员工代表了各个级别，他们在纳米尺度科学的四个主题领域中设想并计划了这种新仪器的非凡实验：电响应材料（包括燃料电池膜、柔性电子器件和纳米电路）、相变（包括超晶格、相分离和图像化）、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）。用户群将为发起新的合作、互动和培训/教育活动提供一个焦点。该仪器将被纳入我们非常成功的专业人员组成的区域设施，该设施向学术，工业和政府科学家和工程师开放。为了鼓励当地文理学院的充分参与，特别是选拔性很强的女子学院布林莫尔学院，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.