95 GHZ SPECTROMETER CRYO-FREE 9T MAGNET UPGRADE

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。 如上所述和我们第一年赠款续期支出中规定的拨款，我们为Acert 95 GHz光谱仪系统购买了一台9T无制冷剂类型的宽孔磁体。该装置从英国低温有限公司购买，于2008年4月中旬安装，不仅具有足够宽的孔径以容纳大型核磁共振式真空温度插入器(VTI)的优点，而且重要的是，显著节省了制冷剂成本。磁铁系统最初预计在2007年秋季到达，但由于主线圈可靠性改进和进一步测试，交付被推迟了大约6个月。虽然Acert的安装正常进行，成功地提升到9T，但随后的主磁铁电源可靠性问题推迟了磁铁系统的最终调试。然而，由于光谱仪本身目前正在进行改造和升级，磁体电源维修/更换停机应该不会造成任何额外的实验计划延迟。 光谱仪的设计和配置的几个方面受到了向新的9T磁体过渡的影响，目前正在解决这些问题。从机械上讲，电桥、谐振器和真空插件需要一种全新的支撑结构，这种支撑结构在物理上也与磁铁外壳隔绝。为了满足这一要求，已经设计了基于重型挤压铝支柱的刚性框架，并将于2008年夏末制造和安装。对于场扫描控制，将创建一个软件模块并将其合并到光谱仪控制集合中，以便与扫描电源进行通信。由分光计控制系统记录的临界磁体温度和场斜率分布将可选地在以后实施。

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. As described and an allocation provided for in our first year grant renewal expenditures, we have acquired a 9T wide-bore magnet of the cryogen-free type for the ACERT 95 GHz spectrometer system. This unit, purchased from Cryogenic, Ltd., U.K., was installed in mid-April, 2008 and offers the benefits of both a sufficiently wide bore to accommodate a large NMR-style vacuum temperature insert (VTI) and, importantly, significant cryogen cost savings. The magnet system was initially expected to arrive in the fall season of 2007 but its delivery was delayed approximately 6 months for main coil reliability modifications and further testing. Although ACERT installation proceeded normally, with successful ramping to 9T, subsequent reliability issues with the main magnet power supply have delayed final commissioning of the magnet system. However, because the spectrometer itself is presently being rebuilt and upgraded, the magnet power supply repair/replacement downtime should not cause any additional experimental program delay. Several aspects of the spectrometer's design and configuration are affected by the transition to the new 9T magnet, and these are presently being addressed. Mechanically, the bridge, resonator and vacuum insert require an entirely new support structure that is also physically isolated from the magnet containment. To meet this requirement, a rigid framework based on heavy-duty extruded aluminum struts has been designed and will be fabricated and installed in late summer 2008. For field sweep control, a software module will be created and incorporated into the spectrometer control ensemble in order to communicate with the sweep power supply. Logging of critical magnet temperatures and field ramp profile by the spectrometer control system will be optionally implemented at a later date.