MICRODIFFRACTION 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。 我们继续对去年安装并投入使用的200毫米长的KB镜系统(芝加哥大学设计)的性能感到满意。 使用这些反射镜可以从低分辨率转换到高分辨率，只需最少的人员干预和时间使用即可完成。这一功能大大增加了仪器的通用性。最近的其他变化包括新的可调飞行管(80、150和200毫米长)，比以前使用的更坚固、更容易调整。再加上更大的探测器(重建的MAR 165)的可用性，这使得仪器能够进行中、小角度的衍射/散射(最常见的配置范围为134 3.5？，最大相机长度为~300？dmin)。我们还重新布置了定位工作台，以便用户更容易进入样品区域。最后，特定于微衍射装置的组件现在被安装在专用面包板上，因此从微探针切换到微衍射只需要几个小时。在屏蔽寄生散射方面有了进一步的改进，现在可以非常迅速地可视化微弱的衍射特性。为了充分利用这一进展，我们最近集中精力改进冷冻保存技术，迄今取得了一些可观的成功。

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. We continue to be pleased with the performance of the 200 mm long KB mirror system (University of Chicago design) that was installed and commissioned last year. Changing from low resolution to high resolution with these mirrors can be performed on-thefly with minimum staff intervention and time usage. This feature greatly increases the versatility of the instrument. Other recent changes include new adjustable flight tubes (80, 150 and 200mm lengths) that are much more robust and easier to adjust than the ones used previously. Combined with the availability of a larger detector (the rebuilt MAR 165) this allows the instrument to be capable of both medium and small angle diffraction/scattering (range 134  3.5 ¿ in the most common configuration, ~ 300 ¿ dmin at maximum camera length) We have also rearranged the positioning stages to allow easier access to the sample area by the users. Finally, the components specific to the micro-diffraction setup are now mounted on a dedicated breadboard so that switching from microprobe to microdiffraction only takes a few hours. Further improvements have been made towards shielding parasitic scattering which now enables weak diffraction characteristics to be visualized very rapidly. In order to take full advantage of this progress, we have more recently concentrated on improving cryo-preservation techniques with some appreciable success to date.