MRI: Acquisition of a Cold-Room Equipped Micro CT

0821056Baker该MRI奖支持收购一台配备冷室的微型CT装置，用于研究冰、冻土和雪/雪中的结构。这项工作的学术价值在于，它将为一些环境问题提供重要的见解，例如气候变化对极地地区的影响。该装置将实现基于X射线吸收的三维微结构的非破坏性重建。将使用冷适应微型CT仪器进行的研究包括了解积雪变质以模拟积雪的影响，表征降雪的微观结构，特别是降雪的孔隙率、渗透率和微观化学，这可以提供有关气候变化的关键信息，以及研究冰中脆性压缩破坏的三维特征，以提供关于北冰洋冰盖破裂的新知识，并对地球破裂-S地壳-提供新的见解。拟议活动的更广泛影响涉及对与气候变化有关的问题的理解和对学生的培训。预计许多研究生将在他们的研究中使用该仪器，本科生将被鼓励从事研究并了解这种仪器。该仪器将纳入国际和平研究所每年讲授的题为《材料表征方法》的课程的实验室部分。预计该仪器的寿命约为10年，将向达特茅斯和外部用户提供该仪器，供他们进行研究。研究结果将被广泛传播。

0821056BakerThis MRI award supports the acquisition of a cold-room equipped micro CT unit for the study of structures in ice, frozen soil and snow/firn. The intellectual merit of the work is that it will provide important insights on a number of environmental questions, such as the effects of climate change on the Polar Regions. The unit will enable non-destructive reconstruction of three dimensional micro-structure based on x-ray absorption. Examples of studies for which the cold-adapted micro-CT instrument will be used include understanding snow metamorphism in order to model the effects of snow-pack, characterizing the microstructure, particularly the porosity, permeability and micro-chemistry of firn, which can yield critical information on climate change, and examining the 3-D character of brittle compressive failure in ice to provide new knowledge about not only the fracture of the ice cover on the Arctic Ocean but also new insights into rupture of the Earth?s crust. The broader impacts of the proposed activity relate to both understanding issues to do with climate change and the training of students. It is expected that many graduate students will use the instrument in their research and undergraduate students will be encouraged to engage in research and learn about instrumentation of this kind. The instrument will be incorporated into the laboratory component of a course taught by the PI every year entitled Methods of Materials Characterization. It is expected that the lifetime of this instrument will be on the order of 10 years and the instrument will be made available to both Dartmouth and outside users for their research. Results of the research will be widely disseminated.