MRI: Acquisition of Environmental Scanning Electron Microscope (ESEM)

传统的电子显微镜是在高真空下操作的，所以如果不将生物材料或精细的无机材料（如凝胶）干燥，从而改变它们的结构，就不可能检查它们。相比之下，ESEM允许在潮湿条件下和在很宽的温度范围内对材料进行高分辨率成像。普林斯顿大学7个院系的研究人员计划进行的研究包括：(1)多孔材料中盐晶体的生长（与建筑材料的劣化有关）；(2)暴露于碳酸中的水泥的腐蚀（与二氧化碳的地质封存有关）；(3)氧化物夹杂物对燃料电池膜结构的影响；(4)模拟火星表面条件下细菌与矿物质的相互作用；(5)疲劳裂纹扩展；(6)神经元突触DNA共享。除了研究之外，该仪器还将用于本科课程和各种K-12外展项目。其中包括教师研究经验（针对当地公立学校教师），普林斯顿大学材料学院（针对来自特伦顿和周边地区的代表性不足的高中生）和材料科学日（代表性不足的学生花一天时间在我们的实验室进行实践活动）。

Conventional electron microscopes operate under high vacuum, so it is not possible to examine biological materials, or delicate inorganic materials (such as gels), without drying them and thereby altering their structure. In contrast, an ESEM permits high resolution imaging of materials under moist conditions, and over a wide range of temperature. Researchers from 7 academic departments at Princeton plan studies including: (1) growth of salt crystals in porous materials (relevant to deterioration of building materials), (2) corrosion of cement exposed to carbonic acid (pertinent to geosequestration of CO2); (3) effects of oxide inclusions on the struc-ture of membranes used in fuel cells; (4) interaction of bacteria with minerals under conditions simulating the surface of Mars; (5) growth of fatigue cracks and (6) DNA sharing at neuron syn-apses. In addition to research, the instrument will be used in undergraduate courses and in a wide variety of K-12 outreach projects. These include Research Experience for Teachers (for local public school teachers), the Princeton University Materials Academy (for under-represented high school students from Trenton and surrounding districts), and Materials Science Days (where un-der-represented students spend the day in hands-on activities in our labs).