VACUUM TEMPERATURE INSERT FOR 95 GHZ SPECTROMETRY

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。 如本节其他部分所述，我们最近为Acert 95 GHz C.W./PULSE光谱仪安装了9T无低温超导磁体。这种磁铁的宽孔为89 mm，允许使用大样本真空温度插件(VTI)，它可以适应我们现有的和预期的未来准光学谐振器结构。对于即时应用，我们选择了为核磁共振波谱设计的改进型Janis Research非光学SuperTran-VP(STVP-200)低温恒温器。这种连续流动低温恒温器在最小化低温恒温器外径的同时最大化了内部样品空间，提供了较大的2.5英寸样品空间，同时可以安装在我们的89 mm口径磁铁中。该插件可实现1.4K至325K的温度范围。 STVP-200VTI的安装目前正在进行中，将首先对以前的95 GHz光谱仪电桥支撑台进行调整。由于无制冷剂磁体包括一个能产生显著振动的往复泵，因此VTI必须与磁体物理隔离。这首先将通过将其支撑板悬挂在带有僵硬三角形侧板的改进型光谱仪桥架起落架上，并在2008年夏季晚些时候将其替换的铝制支撑结构中，从连接到主框架构件的横向支撑支柱上悬挂。 VTI样品空间的温度调节将使用目前95 GHz光谱仪系统的Lakeshor331低温温度控制器来保持。

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 elsewhere in this section, we have recently installed a 9T cryogen-free superconducting magnet for the ACERT 95GHz c.w./pulse spectrometer. The wide bore of this magnet, 89 mm, permits the use of a large-sample vacuum temperature insert (VTI) which can accommodate our existing and contemplated future quasioptical resonator structures. For the instant application, we have chosen a modified Janis Research non-optical SuperTran-VP (STVP-200) cryostat designed for NMR spectroscopy. This continuous flow cryostat maximizes the internal sample space while still minimizing the cryostat outside diameter, providing a large 2.5" sample space while fitting within our 89 mm bore magnet. A temperature range of 1.4 K to 325 K is accessible with this insert. Installation of the STVP-200 VTI is currently in progress and will be initially implemented with an adaptation of the previous 95GHz spectrometer bridge support table. Because the cryogen-free magnet includes a reciprocating pump which generates significant vibrations, the VTI must be physically isolated from the magnet. This will initially be accomplished by suspending its support plate from the modified spectrometer bridge undercarriage frame with stiff triangular sideplates, and, in the aluminum strutwork configuration that will replace it later in summer 2008, from cross-support struts attached to the main frame members. Temperature regulation of the VTI sample space will be maintained using the present 95GHz spectrometer system's Lakeshore model 331Cryogenic Temperature Controller.