MICRODIFFRACTION AT BEAMLINES X25 AND X29

光束线 X25 和 X29 处的微衍射

• 批准号: 8170688
• 负责人: HOWARD T ROBINSON
• 金额: $ 21.95万
• 依托单位: BROOKHAVEN SCIENCE ASSOC-BROOKHAVEN LAB
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2011-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8170688
• 关键词: Accounting; Amplifiers; Behavior; Burn injury; Cacodylic Acid; Chronic; Collaborations; Complement; Computer Retrieval of Information on Scientific Projects Database; Crystallography; Data; Data Set; Development; Devices; Diagnostic; Diamond; Environment; Exposure to; Fluorescence; Funding; Glare; Glycerol; Grant; Harvest; Image; Imagery; Institution; Metals; Monitor; Mothers; Motor; Oceans; Optics; Positioning Attribute; Procedures; Process; Research; Research Personnel; Resources; Sampling; Scanning; Scientist; Side; Solutions; Source; Technology; Thinking; United States National Institutes of Health; Universities; Work; base; beamline; detector; digital; distilled alcoholic beverage; improved; instrumentation; repaired; research study; software development; tool

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. Microdiffraction at beamlines X25 and X29 H¿roux, Robinson Objectives  Both X25 and X29 are benefitting from improved capability to collect diffraction data routinely from smaller crystals. We have coordinated improvements between the two undulator beamlines to provide the users with a more consistent environment. We are pursuing the development of better ways to find small crystals with both conventional optics and with a grid search using x-rays. We continue implementing better control of the divergence to the users via CBASS. We want to implement more diagnostic tools to monitor the stability of the x-ray beam delivered by the NSLS. We are also deploying an automounter at X25 similar to that at X29. Results  Users are routinely collecting data with a 50x50 ¿m2 beam by slitting the apertures in the hutch to the desired size, and restricting the beam size upstream to control beam divergence. Macros to calibrate the slits have been implemented at both beamlines. Micro-crystal experiments by Soares using a beam size of approximately 10x10 ¿m2 did not require any special assistance from the beamline scientist. A very useful procedure to visualize the size of the beam at the sample (apertures + divergence) possible by the "burning" of a solution of glycerol containing cacodylic acid. This procedure takes only a few seconds of exposure to the x-rays and has a dual purpose of establishing the beam size and confirming alignment of the spindle with the beam. A chronic problem in crystallography is to localize the crystal in an ocean of mother liquor. Optical visualization is a problem since there is glare on the mother liquor, there is optical distortion, and one direction is not visible (through the side of the loop). Better digital cameras have been implemented at both beamlines. We have also implemented x-ray grid searches to supplement the optical technology (see software development by Skinner). We installed a beam-position monitor just downstream from the monochromator. This device enables us to record the position of the beam as well as the intensity for each image. The users now have plots of the behavior of the beam at the end of the html log for every dataset taken at X25. We will complement this work by the addition of a white-beam position monitor. Repair of the focusing-mirror motors has enabled us to improve the optimization of the vertical size of the beam (set at 70-90 ¿m) with a horizontal focus of 260 ¿m. We purchased an amplifier / multichannel-analyzer for a new x-ray fluorescence emission detector. This is a mobile unit which can be brought to any of our beamlines at the user's request. Within seconds, the users can scan the sample and determine what metals are present. The Q315 detector was upgraded last summer. Plans  We will install an automounter at X25 soon. We are in the process of acquiring a white-beam position monitor. This work is done in collaboration with the NSLS-II experimental facilities division (J. Kiester), BNL instrumentation group (J. Smedley) and Case Western University (J. Bohon). This new monitor will be positioned where a previous wBPM was installed at X25 years ago. This wBPM consists of two synthetic diamond crystals mounted in a cooled chamber. The photocurrent will be harvested and will give us information about the quality and stability of the white beam. Significance  Having a very good understanding of the beam quality and stability is fundamental when thinking about mini to micro beams. Developing a user base for this type of setup is important in order to prepare for new experiments done at NSLS-II. Any development has to take into account the users and their need. This is done by combining the efforts of X29 and X25 together.

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 光束线X25和X29处的微衍射 罗宾逊？赫鲁 目标  X25和X29都受益于从较小晶体常规收集衍射数据的改进能力。我们已经协调了两个波荡器光束线之间的改进，为用户提供更一致的环境。我们正在寻求开发更好的方法，通过传统光学和使用X射线的网格搜索来寻找小晶体。我们继续通过CBASS对用户实施更好的分歧控制。我们希望使用更多的诊断工具来监测NSLS提供的X射线束的稳定性。我们还在X25部署了一个类似于X29的自动挂载器。 结果  用户通常通过将箱中的孔径切割成所需尺寸，并限制上游的光束尺寸以控制光束发散度，从而使用50 × 50 <$m2的光束收集数据。在两条光束线上都实现了校准狭缝的宏。Soares使用大约10x10 <$m2的光束尺寸进行的微晶实验不需要光束线科学家的任何特殊帮助。一个非常有用的程序来可视化光束的大小在样品（孔径+发散）可能通过"燃烧"的甘油溶液中含有cacodylic酸。该过程仅需几秒钟的X射线曝光时间，具有确定光束尺寸和确认主轴与光束对准的双重目的。结晶学中的一个长期问题是将晶体定位在母液的海洋中。光学可视化是一个问题，因为母液上有眩光，有光学失真，一个方向是不可见的（通过环的侧面）。 更好的数码相机已实施在两个光束线。我们还实施了X射线网格搜索，以补充光学技术（参见Skinner的软件开发）。 我们在单色仪的下游安装了一个光束位置监视器。这个设备使我们能够记录光束的位置以及每个图像的强度。用户现在可以在html日志的末尾为X25处采集的每个数据集绘制梁的行为图。我们将通过增加一个白光位置监视器来补充这项工作。 对聚焦镜电机的修复使我们能够优化光束的垂直尺寸（设置为70 - 90 <$m），水平焦点为260 <$m。 我们为新的X射线荧光发射检测器购买了放大器/多通道分析仪。这是一个移动的单元，可根据用户的要求将其带到我们的任何光束线上。在几秒钟内，用户可以扫描样品并确定存在哪些金属。 Q315探测器在去年夏天进行了升级。 计划  我们很快会在X25上安装一个自动装载机。我们正在获取一个白光位置监视器。这项工作是与NSLS-II实验设施部门（J.Kiester），BNL仪器组（J.Smedley）和Case Western大学（J.Bohon）合作完成的。 这个新的监视器将定位在X25年前安装的wBPM上。这种wBPM由安装在冷却室中的两个合成金刚石晶体组成。 光电流将被收集，并将为我们提供有关白色光束质量和稳定性的信息。 意义  在考虑小型到微型光束时，对光束质量和稳定性有很好的了解是至关重要的。为这种类型的设置建立用户基础是重要的，以便为在NSLS-II进行的新实验做好准备。任何开发都必须考虑用户及其需求。这是通过将X29和X25的努力结合在一起来完成的。