ESR MICROSCOPE MKII MAGNETIC FIELD STABILIZTION SYSTEM

ESR 显微镜 MKII 磁场稳定系统

• 批准号: 8172220
• 负责人: CURT R DUNNAM
• 金额: $ 0.89万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8172220
• 关键词: Communication; Computer Retrieval of Information on Scientific Projects Database; Computer software; Development; Electronics; Face; Feedback; Frequencies; Funding; Grant; Hybrids; Institution; Microscope; Modeling; Output; Power Sources; Published Comment; Regulation; Research; Research Personnel; Resolution; Resources; Source; System; United States National Institutes of Health; Work; computerized data processing; design; instrument; magnetic field; virtual

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. Our current Ku-band ESR microimaging system includes a large (15 inch pole face) resistive magnet that provides good working space for ESR microimaging (ESRM) development purposes but is powered by an older Varian V-2500 linear regulated power source to which we have attached a patchwork of several discrete feedback systems for the purpose of accurate field regulation. Currently the feedback systems include a Hall-input Field Dial console, a Lakeshore model 475 Hall field controller and a modified Varian V-4542 field/frequency lock (FFL) system consisting of EPR probe and signal processing electronics. Although this system has performed in a generally satisfactory manner to date, its reliability is marginal, particularly when operating in (Hall-stabilized) field regulation mode for setup purposes, and its use, from an operational viewpoint, is unnecessarily complicated. During the course of upgrading to the new 15KW Gensys magnet power supply (Subproject 0218), we propose replacing the existing regulation system with a newly-designed hybrid system incorporating the present Lakeshore 475 Hall field controller and Varian V-4542 field/frequency lock probe, adding the necessary mode control electronics and communication channel to the Gensys power source. This highly integrated regulation system will also include the programmable precision reference required for offsetting the relatively low resolution (16bit) Lakeshore controller output to achieve ca 20b/10 mG resolution to 1.0T. An option for input dithering can also be included as may be required. Provision is included in current design specification for full remote control of programmable field regulation parameters and functional modes so that the system can operate compatibly with the ESRM LabView VI (virtual instrument) software. We plan to employ essentially the same design in the construction of a second hybrid regulation system to provide Hall/FFL magnetic field control for our proposed 35 GHz ESR microscope (Subproject 0138).

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 我们当前的 Ku 波段 ESR 微成像系统包括一个大型（15 英寸极面）电阻磁体，为 ESR 微成像 (ESRM) 开发目的提供良好的工作空间，但由较旧的 Varian V-2500 线性调节电源供电，我们在该电源上连接了多个离散反馈系统的拼凑而成，以实现精确的场调节。目前，反馈系统包括霍尔输入现场拨号控制台、Lakeshore 475 型霍尔现场控制器和改进的 Varian V-4542 场/频率锁定 (FFL) 系统，该系统由 EPR 探头和信号处理电子设备组成。尽管该系统迄今为止的表现总体令人满意，但其可靠性很有限，特别是当出于设置目的而在（霍尔稳定）场调节模式下运行时，并且从操作角度来看，其使用不必要地复杂。 在升级到新的 15KW Gensys 磁体电源（子项目 0218）的过程中，我们建议用新设计的混合系统替换现有的调节系统，该系统包含现有的 Lakeshore 475 霍尔场控制器和 Varian V-4542 场/频率锁定探头，为 Gensys 电源添加必要的模式控制电子设备和通信通道。该高度集成的调节系统还将包括抵消相对较低分辨率（16 位）Lakeshore 控制器输出所需的可编程精密基准，以实现约 20b/10 mG 分辨率至 1.0T。根据需要，还可以包括输入抖动选项。当前的设计规范中包含对可编程现场调节参数和功能模式进行完全远程控制的规定，以便系统可以与 ESRM LabView VI（虚拟仪器）软件兼容运行。 我们计划在构建第二个混合调节系统时采用基本相同的设计，为我们提出的 35 GHz ESR 显微镜（子项目 0138）提供霍尔/FFL 磁场控制。