SAXS DEVELOPMENT

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 SAXS的开发时间用于当前赠款周期的核心项目活动，并收集初步数据，为下一个赠款周期做准备。研制了一台新型的WAXS仪器，并进行了测试。由于背景散射大大减少，新的WAXS设置提供了比旧WAXS仪器更好的数据质量。自那以后，新的WAXS仪器已被用于许多用户项目。另一项主要活动是时间分辨SAXS模式的探测器测试和评估。我们能够证明，Aviex CCD的条纹相机模式可以为许多时间分辨率的SAXS应用提供足够好的数据。与RMD公司合作的基于EMCCD技术的原型探测器的测试表明，该概念对于时间分辨SAXS应用也是可行的。计划进行进一步的测试，以使这种检测器与停流装置同步。我们还与ANL的简·赫斯勒合作，评估了一种能够进行4微秒成帧的新型探测器。我们确定，在目前的开发阶段，这种探测器的噪声水平太高，不适用于生物样本。我们已经确定了在未来这种类型的探测器中降低噪声的途径。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. SAXS development time was devoted to core project activities in the current grant cycle and to gathering preliminary data in preparation for the next. A new WAXS instrument was built and tested. The new WAXS setup offers much better data quality than the old WAXS instrument, due to much reduced background scattering. The new WAXS instrument has since been used in many user projects. Another major activity was detector testing and evaluation for time resolved SAXS modes. We were able to demonstrate that the streak camera mode of Aviex CCD can produce good enough data for many time resolved SAXS applications. Test of a prototype detector based on EMCCD technology in collaboration with RMD Inc. showed that this concept is also viable for time resolved SAXS applications. Further testing is planned for synchronizing such detectors with the stopped flow device. We also evaluated a new detector type capable of 4 microsecond time framing in collaboration with Jan Hessler of ANL. We determined that this detector, at its present stage of development has too high a noise level to be useful with biological samples. We have identified paths to reducing noise in future detectors of this type.