DEVELOPMENT OF 750MHZ SUPERCONDUCTING PROBE

750MHZ超导探头的研制

• 批准号: 7369574
• 负责人: William W Brey
• 金额: $ 4.63万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-05-01 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7369574
• 关键词: DEVELOPMENT; 750MHZ; SUPERCONDUCTING; PROBE

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. Superconducting NMR probes contain cooled rf coils made of superconducting material that result in improved signal to noise for the experiment. These are commercially available at 500 and 600 MHZ and the goal in Core 3 is to construct improved probes at 750MHz in collaboration with colleagues at the NHMFL and Bruker Instruments. In the spring of 2003, we changed our goal to a 600 MHz 1 mm HCN probe with a single-axis pulsed field gradient. Withers has already built the mounting hardware and 13C and 2H coils. They are now building the 1H and 15N coils, and their initial attempt lead to a 1H coil which resonated ~5% in frequency than expected. The batch of coils they tested all had unusually low Q values, and they now are convinced that coils were made from a bad batch of YBCO superconducting film. More superconducting wafers will be coming soon, and with the help of Saikat Saha, a postdoctoral associate at the NHMFL, we are also making real progress in modeling and better understanding the behavior of the HTS resonators. It appears that with this improved understanding we can improve our ability to design for new frequency and size requirements, but we may also be able to improve the current handling and RF homogeneity of the resonators. Dr. Saha has been using a method of moments (MoM) simulation package (IE3D from Zeland Software) to model resonance frequency and current distribution in HTS coil designs. The MoM approach is faster and more practical for planar coils, which must be subdivided into hundreds of quasi-2D cells. It handles only planar dielectrics, but it is possible to include the cylindrical shield used in the cryoprobe. We anticipate testing a working probe during this next year. If this works, this 1 mm HTS probe will have the highest per volume S/N in any probe built to date.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子弹和调查员（PI）可能已经从其他NIH来源获得了主要资金，因此可以在其他清晰的条目中代表。列出的机构适用于该中心，这不一定是调查员的机构。超导NMR探针包含由超导材料制成的冷却的RF线圈，从而改善了实验信号的信号。这些以500和600 MHz的价格在市售中可用，Core 3的目标是与NHMFL和Bruker Instruments的同事合作构建750MHz的改进探针。 在2003年春季，我们将目标更改为具有单轴脉冲场梯度的600 MM HCN探针。 Withers已经建造了安装硬件以及13C和2H线圈。他们现在正在构建1H和15N线圈，最初的尝试导致1H线圈的频率比预期的频率约为5％。他们测试的一批线圈都具有异常较低的Q值，现在他们坚信线圈是由一批不良的YBCO超导膜制成的。 更多的超导晶片将很快到来，在NHMFL的博士后助理Saikat Saha的帮助下，我们在建模和更好地理解HTS谐振器的行为方面也取得了真正的进步。似乎有了这种改善的理解，我们可以提高设计新频率和尺寸要求的能力，但是我们也可以改善谐振器的当前处理和RF均质性。 Saha博士一直在使用一种矩（MOM）模拟软件包（来自Zeland软件的IE3D）的方法来模拟HTS线圈设计中的共振频率和电流分布。对于平面线圈，妈妈的方法更快，更实用，必须将其细分为数百个准2D细胞。它仅处理平面电介质，但可以包括冷冻探针中使用的圆柱形盾。 我们预计明年将测试工作调查。如果有效，则该1 mM HTS探针在迄今为止构建的任何探针中的每卷S/N最高。