ADVANCED ARRAY DETECTOR FOR XRAY SPECTROSCOPY

用于 X 射线光谱学的先进阵列探测器

• 批准号: 2766829
• 负责人: MARK R CHANCE
• 金额: $ 19.2万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-04 至 2000-01-03
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2766829
• 关键词: X ray spectrometry; biomedical equipment; biomedical equipment purchase; synchrotrons

X-ray absorption spectroscopy (XAS) is a valuable technique for studying a variety of metal sites in biological systems. The technique measures the transition of core electronic states of the metal to excited electronic states or continuum states. Spectral analysis near the electronic transition (x-ray absorption near-edge structure or XANES) provides information on the metal's charge state and geometry. Spectral analysis above the absorption edge (from the edge to 10-15 percent above the edge in energy), so called Extended X-ray Absorption Fine Structure or EXAFS, provides complementary structural information like, numbers, types, and distances of ligands or neighboring atoms. The Albert Einstein Center for Synchrotron Biosciences, an NIH Resource Center at the National Synchrotron Light Source, operates a beamline (X9B) and provides comprehensive user support that has provided access to x-ray spectroscopy experiments for NIH funded investigators for over 10 years. This proposal requests an Advanced Array Detector for X-ray spectroscopy that can count 3 times faster than our existing detector. Recent improvements in beamline X9B make current XAS experiments inefficient. The 4 fold increased x-ray flux now available for XAS experiments cannot be adequately handled by the antiquated electronics of the existing XAS detector. XAS is a major component of the NIH funded programs of each of the 7 major users listed in the proposal. These users have 13 NIH grants that will benefit from this instrument. These users also have over 60 XAS publications in the last three years using the facilities and current detector of the Resource Center. In addition, these major users identify 18 NIH funded collaborators (with 20 additional NIH grant programs pertinent to the proposal) who will benefit from the acquisition of this instrument. The available beamtime for XAS on the X9B beamline is 2-fold oversubscribed. These NIH funded users and their collaborators have few alternatives for completing their experimental programs. Increasing throughput by a factor of three using the new instrument would be an extraordinary benefit to this productive and well-funded user community.

X射线吸收光谱(XAS)是研究生物系统中各种金属位置的一种有价值的技术。这项技术测量了金属的核心电子态到激发电子态或连续态的转变。电子跃迁附近的光谱分析(x射线吸收近边结构或XANES)提供了有关金属电荷状态和几何形状的信息。吸收边以上的光谱分析(从能量上的边缘到边缘以上10%-15%)，即所谓的扩展X射线吸收精细结构或EXAFS，提供了补充结构信息，如配体或邻近原子的数量、类型和距离。阿尔伯特·爱因斯坦同步加速器生物科学中心是国家同步加速器光源的NIH资源中心，运营着一条光束线(X9B)，并提供全面的用户支持，为NIH资助的研究人员提供了10多年的X射线光谱分析实验。这项提议需要一种先进的X射线光谱学阵列探测器，它的计数速度比我们现有的探测器快3倍。光束线X9B的最新改进使目前的XAS实验效率低下。现有XAS探测器陈旧的电子设备无法充分处理现在XAS实验中可用的4倍增加的X射线通量。XAS是NIH资助的计划的一个主要组成部分，该计划列出了该提案中的7个主要用户。这些用户拥有13笔NIH补助金，将从这一工具中受益。这些用户还在过去三年中使用资源中心的设施和当前探测器拥有60多份XAS出版物。此外，这些主要用户确定了18个由NIH资助的合作者(还有20个与该计划相关的NIH赠款项目)，他们将从这一工具的收购中受益。X9B波束线上XAS的可用波束时间超额认购了2倍。这些由NIH资助的用户和他们的合作者几乎没有完成他们的实验计划的选择。使用新工具将吞吐量提高到原来的三倍，对这个多产且资金充足的用户群体来说将是一个非同寻常的好处。