SPECTROMETER FOR TIME-RESOLVED 2D-FT ESR

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 一种能够捕捉纳秒时间尺度上的瞬变事件并同时记录较慢的脉冲傅立叶变换电子顺磁共振光谱仪 在微秒到毫秒的时间尺度上，动力学在其他地方还没有实现。ACERT的一系列技术发展使这种光谱仪得以实现。这样的光谱仪需要非常短的死区时间、高脉冲序列重复率、能够在每次发射时(几微秒内)更新所有脉冲序列参数的独特计时系统，以及以如此高的速率捕获和处理瞬变信号。此外，在较高的工作频率下可以获得最短的死区时间和最高的灵敏度。所有这些组件都是在Acert开发的，并正在集成到一个独特的光谱仪中。Acert最近收购了Bruker E500 CW ESR光谱仪，为该项目提供了一个12英寸的电阻电磁铁，从而在一定程度上消除了在几个可用电磁铁周围安排几个基本上不兼容的脉冲ESR项目的不便。从X波段到Ku波段的2D-Eldor实验将围绕这块磁铁进行。现有的电磁电源允许这种新的光谱仪工作到Ku波段，在那里展示了高质量的2D-Eldor。目前运营仅限于X波段(基于8kW峰值功率行波管)，但也计划在Ku波段运营。Ka波段的运行也在计划中，但必须与PDS光谱仪结合使用。该光谱仪将与闭环流系统一起用于研究脉冲激光照射下的光过程，并将与快速混合系统一起用于研究蛋白质折叠。宽带8-18 GHz(五个频段)微波桥，建于2000年初，S，将用于现代改进型。时间分辨操作将完全基于具有实时控制的专用多功能脉冲编程器，ACERT-BN2或其后继者。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. A pulse FT ESR spectrometer capable of capturing transient events on nanosecond time scales and simultaneously recording slower Kinetics on microsecond to millisecond time scale has not been realized elsewhere. A series of technical developments at ACERT have enabled implementation of such a spectrometer. Such a spectrometer requires very short dead-times, high pulse-sequence repetition rates, a unique timing system capable of updating all pulse sequence parameters on every shot (in a few microseconds), and capturing and processing transient signals at such high rates. Also, the shortest dead-times and the highest sensitivity can be achieved at a higher working frequency. All these components have been developed at ACERT and are being integrated into a unique spectrometer. Recent acquisition by ACERT of a Bruker E500 CW ESR spectrometer made available a 12-inch resistive electromagnet for this project, thereby relieving to some extent the inconvenience of arranging several largely incompatible pulse ESR projects around a few available electromagnets. 2D-ELDOR experiments from X to Ku band will be built around this magnet. The existing electromagnet power supply allows this new spectrometer operation up to Ku band, where high quality 2D-ELDOR was demonstrated. Currently the operation is limited to X-band (based on 8 kW peak power TWTA), but operation at Ku band is also planned. Operation at Ka band is also planned, but has to be combined with PDS spectrometer. The spectrometer will be used with closed-loop flow system to study photo processes under pulse laser illumination and with rapid mixing system to study protein folding. Broadband 8-18 GHz (in five bands) microwave bridge, built in early 2000's, will be used in a modern modified version. Time-resolved operation will be entirely based on a dedicated versatile pulse-programmer with real-time control, ACERT-BN2 or its successor.