VACUUM TEMPERATURE INSERT FOR 95 GHZ SPECTROMETRY

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子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./脉冲分光计该磁体的宽孔为89 mm，允许使用大样本真空温度插入件（VTI），该插入件可以容纳我们现有的和预期的未来准光学谐振器结构。对于当前的应用，我们选择了一种改进的Janis Research非光学SuperTran-VP（STVP-200）低温恒温器，该低温恒温器设计用于NMR光谱学。 这款连续流低温恒温器最大化了内部样品空间，同时最小化了低温恒温器的外径，提供了一个2.5”的大样品空间，同时适合我们的89 mm孔磁体。使用此插件可达到1.4 K至325 K的温度范围。 STVP-200 VTI的安装目前正在进行中，最初将采用以前的95 GHz频谱仪桥接支持表进行调整。由于无冷冻剂磁体包括产生显著振动的往复泵，因此VTI必须与磁体物理隔离。这将首先通过将其支撑板悬挂在改进的光谱仪桥底架上来实现，该底架具有刚性三角形侧板，并且在2008年夏季晚些时候将取代它的铝支撑结构中，从连接到主框架构件的交叉支撑支柱上悬挂。 VTI样品空间的温度调节将使用目前的95 GHz光谱仪系统的Lakeshore 331型低温温度控制器来维持。

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.