MRI: Acquisition of an Environmental Scanning Electron Microscope to Enable Cross-Disciplinary Research and Education

加州大学戴维斯分校几所学院的研究人员使用环境扫描电子显微镜来可视化和研究材料随时间的变化，从纳米到整个设备或系统的大小。测量是在材料的工作环境中进行的，例如，从水蒸气到受控类型和压力的气体。显微镜位于加州大学戴维斯分校主校区材料科学系的一个广泛共享的设施中，为来自校园、医疗中心、当地社区大学、行业以及加利福尼亚州中央山谷的高中教师和学生提供服务。该团队以“在科学中看到”为总主题，吸引和增加校园内外少数族裔学生的参与。环境扫描电子显微镜使研究小组能够在多个长度尺度上演示各种样品在其自然环境中或接近其自然环境的成像，而最不需要事先进行样品处理和准备。获得环境扫描电子显微镜后，主要研究人员只需进行少量修改，即可在高温、施加机械应力和受控大气下对材料和复杂系统进行现场表征。在高达4000帕斯卡的适当气体或蒸汽环境下运行，可以成像绝缘的、电子束敏感的和水合的材料和系统，如陶瓷、聚合物和植物组织。使用该显微镜进行的研究促进了我们在跨学科研究课题中的基础科学知识，包括金属薄膜的团聚动力学，纳米级加工过程中陶瓷微结构的演变，纳米结构的三维组装，骨的断裂力学，与食品安全有关的植物-微生物相互作用，眼镜片的结构-功能关系，以及高性能电子设备的失效机制。在调查过程中，研究人员还确定了实现不同成像模式、学科和数据源之间的数据关联的方法。相关表征使得在整个器件结构和整个生物体中实现结构-形态-功能关系成为可能。

Researchers in several colleges at the University of California, Davis use an environmental scanning electron microscope to visualize and study changes in materials with time, from nanometer to the size of a whole device or system. The measurements are carried out in the working environment of materials, e.g., from water vapor to controlled type and pressure of gases. The microscopy is located at a broadly shared facility in the materials science department on the UC Davis main campus, serving users from campus, the medical center, local community colleges, industry and with high-school teachers and students in the Central Valley, California. The team uses a general theme of "Seeing in Science" to attract and increase participation from underrepresented minority students on and off campus. The environmental scanning electron microscope allows the team to demonstrate imaging of various samples on multiple length-scales at or close to their native environments with minimal need of prior sample treatment and preparation.Acquisition of an environmental scanning electron microscopy, with a small modification by the principal investigators, enables in-situ characterization of materials and complex systems under high temperatures, applied mechanical stress, and controlled atmospheres. Operation under appropriate gas or vapor environments up to 4000 Pascals makes it possible to image insulating, electron beam-sensitive and hydrated materials and systems, such as ceramics, polymers and plant tissue. Research conducted using this microscope advances our fundamental scientific knowledge in interdisciplinary research topics, including the agglomeration kinetics of thin metal films, ceramics microstructure evolution during nanoscale processing, 3-dimensional assembly of nanostructures, fracture mechanics of bone, plant-microbe interaction for food safety, structure-functionality relationships of ocular lenses, and failure mechanisms of high-powered electronics. During the course of investigation, the researchers also identify approaches to enable data correlation between different imaging modes, disciplines, and data sources. Correlative characterization makes it possible to achieve structure-morphology-functionality relationships in entire device structures and whole organisms.