MRI: Acquisition of a High-resolution X-ray Microscope for Nondestructive 2D, 3D and 4D Characterization of Microstructures in Cross-Disciplinary Research

x射线计算机断层扫描（CT）是一种基于从大量视角拍摄的一系列二维x射线图像重建物体外部和内部特征的三维（3D）图像的物体无损检测方法。医学CT成像通常被用作诊断工具，使用更高x射线强度的类似方法可以为非活体样本提供非常详细的成像，用于许多科学和工程领域的广泛研究应用。该主要研究仪器（MRI）奖支持获得高分辨率的3D x射线显微镜，该显微镜能够产生三维分辨率小于1微米（约比人类头发宽度小100倍）的图像。该系统将位于斯坦福纳米共享设施，这是一个核心设施，为斯坦福大学和附近机构的研究人员提供最先进的样品表征和分析仪器。该仪器将推动来自斯坦福大学地球能源与环境科学、工程、人文科学和医学等多个学科的研究人员以及圣何塞州立大学和加州科学院（位于旧金山的博物馆、教育中心和研究机构）的研究人员的创新研究。高分辨率x射线显微镜将填补斯坦福大学目前没有设备能够产生无损3D断层扫描图像的长度范围（0.4至40微米）的空白，从而提高斯坦福大学在材料科学、地球科学和生命科学方面进行前沿研究的能力。它将支持材料科学、地球科学和生命科学领域的前沿基础研究。研究人员将使用该仪器分析页岩的微观结构，页岩中包含各种大小的孔隙和其他特征，从而可以研究更有效地提取石油和封存人为二氧化碳。在长工作距离下以高分辨率成像大样本的能力将被用于研究涂有自修复聚合物的硅微粒阳极，以优化设计更持久的电池。该仪器将用于从小鼠到人类的哺乳动物的内耳骨和鼓膜的高分辨率成像，以帮助更详细地模拟听力机制和开发用于纠正听力异常的新型设备。改进微机电系统（MEMS）器件制造的研究人员将使用显微镜对器件的内部结构进行无损检查，以尽量减少或消除疲劳（重复加载）故障，从而大大延长器件和传感器的使用寿命，用于广泛的应用。双能量成像能力将允许在一次扫描中同时收集软骨、骨骼和脉管系统的高分辨率图像，为骨骼发育和愈合过程提供新的见解。加州科学院的研究人员将利用该仪器的高分辨率、相对比成像能力，对组织界面进行详细检查，作为进化小型化的解剖和生理影响研究的一部分。通过这些和许多其他项目，该仪器将成为斯坦福大学研究基础设施的关键部分，并扩大科学和工程学科研究的范围和影响。

X-ray computed tomography (CT) is an approach to nondestructive examination of objects based on reconstructing three-dimensional (3D) images of the external and internal features of an object from a series of two-dimensional X-ray images taken at a large number of viewing angles. Medical CT imaging is commonly used as a diagnostic tool, and similar approaches using higher X-ray intensities can allow very detailed imaging of non-living samples for a wide range of research applications across many fields of science and engineering. This Major Research Instrumentation (MRI) award supports the acquisition of a high-resolution, 3D X-ray microscope capable of producing images with three-dimensional resolution smaller than 1µm (about 100 times smaller than the width of a human hair). This system will be located in the Stanford Nano Shared Facilities, a core facility providing researchers across Stanford University and from nearby institutions with state-of-the-art instruments for specimen characterization and analysis. This instrument will advance innovative research by investigators from multiple disciplines across Stanford's Schools of Earth Energy & Environmental Sciences, Engineering, Humanities & Sciences, and Medicine, as well as investigators from San Jose State University and the California Academy of Sciences, a museum, educational center and research facility in San Francisco.The high-resolution X-ray microscope will improve Stanford's ability to conduct leading-edge research in materials science, earth science, and life science by filling the gap in length scale (0.4 to 40 µm) within which no equipment currently at Stanford can generate non-destructive 3D tomography images. It will support leading-edge basic research in materials science, earth science, and life science. Researchers will use the instrument to analyze the microstructure of shale rock, which contains pores and other features at a range of sizes, enabling studies on more efficient extraction of petroleum and sequestration of anthropogenic carbon dioxide. The ability to image large samples with high resolution at a long working distance will be exploited to study silicon microparticle anodes coated with self-healing polymers for optimal design of longer-lasting batteries. The instrument will be used for high-resolution imaging of inner-ear bones and the tympanic membrane of mammals ranging from mice to humans to aid in more detailed modeling of the mechanics of hearing and development of novel devices for correcting hearing abnormalities. Researchers on improved fabrication of micro-electro-mechanical systems (MEMS) devices will use the microscope to nondestructively examine the internal structure of devices designed to minimize or eliminate fatigue (repeated loading) failure, dramatically extending the useful life of devices and sensors for a wide range of applications. The dual-energy imaging capacity will allow simultaneous collection of high-resolution images of cartilage, bone and vasculature in a single scan, providing new insights into the processes of skeletal development and healing. Researchers at the California Academy of Sciences will take advantage of the instrument's high-resolution, phase contrast imaging capabilities for detailed examination of tissue interfaces as part of studies on the anatomical and physiological effects of evolutionary miniaturization. Through these and many other projects, this instrument will become a key part of Stanford University's research infrastructure and enhance the scope and impact of research across a wide range of science and engineering disciplines.