A 1.5-T superconducting solenoid-dipole magnet for a magic-angle spinning field

用于魔角旋转场的 1.5T 超导螺线管偶极磁体

• 批准号: 8534118
• 负责人: Yukikazu Iwasa
• 金额: $ 61.79万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-19 至 2015-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8534118
• 关键词: Adopted; Bathing; Data; Detection; Devices; Diagnosis; Disease; Drug toxicity; Ensure; France; Frequencies; Head; Health; Helium; Housing; Human; Laboratories; Liquid substance; Lung; Magic; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Magnetism; Measures; Mechanics; Methods; Mission; Monitor; Nitrogen; Pacific Northwest; Phase; Predisposition; Public Health; Research; Research Personnel; Rotation; Science; Solid; Source; Staging; System; Temperature; Testing; Therapy Evaluation; Time; Tissues; Work; cold temperature; cryogenics; cryostat; design; disorder prevention; improved; innovation; metabolic abnormality assessment; novel; operation; programs; tool; vector

Phase 1 of this 2-phase program has two specific aims: 1) successful completion of a magic-angle-field (MAF) magnet of a significant field strength with an NMR-quality field homogeneity for slow MAS (magic-angle-spinning) MRI/NMR; and 2) application and demonstration with the proposed system of an innovative cryogenic system suitable for a superconducting magnet spinning in Phase 1 slowly (~0.1 Hz) and in Phase 2 at 6 Hz. Unlike a conventional NMR or MRI magnet that has a field vector of NMR quality directed only in one axis, an MAF vector may be decomposed into two field vectors, one directed in one axis and the other in the direction normal to the first axis. The best, and perhaps the easiest, way to ensure an NMR-quality field directed at an angle of 54.74o from the magnet axis (also the rotation axis) is to ensure independently an NMR-quality field generated by each of the coils comprising an MAF magnet. This is the crux of our innovative design concept to build a successful superconducting MAF magnet: a combination of an axial z-field solenoid coil and an x-axis field dipole coil, each generating an NMR-quality field of a specific strength. By adjusting each coil's field strength, we will be able to achieve with this Phase 1 magnet both requirements of field strength (here 1.5 T) and angle (54.74o). With this magnet, for the very first time, MAS NMR/MRI sciences will have a superconducting MAF magnet that generates an NMR- quality field of significant strength, e.g., 1.5 T >> 36 gauss (the previous high by the UC Berkeley group), operated in persistent mode. Another notable significance is an innovative cryogenics design applied to this magnet (also to used in Phase 2). Instead of operated in a bath of liquid helium (LHe), the magnet will be immersed in solid nitrogen (SN2). (In phase 2,the magnet will be housed in a cryostat which will rotate at 6 Hz.) This all-solid cold body ameliorates thermo-fluid issues associated with LHe under rotation. Also, the presence of SN2 in the cold body not only ensures a more uniform temperature throughout the windings but also provides a large thermal mass, enabling the magnet to maintain its operating field over a time period even when the primarily cooling source (LHe in Phase 1) is shut off. In summary, the successful completion of this 2-phase program will open new opportunities in MAS NMR/MRI sciences, which in turn will open new avenues to modern instrumental analysis, ultimately leading to novel non-invasive biomedical tools for analysis, diagnosis, and disease prevention.

这个两阶段计划的第一阶段有两个具体目标：1) 成功完成 具有 NMR 质量磁场的显着场强的魔角场 (MAF) 磁铁 慢速 MAS（魔角旋转）MRI/NMR 的均匀性； 2）申请和 用所提议的系统演示适用于的创新低温系统 超导磁体在第 1 阶段缓慢旋转（~0.1 Hz），在第 2 阶段以 6 Hz 旋转。 与具有 NMR 质量场矢量的传统 NMR 或 MRI 磁体不同 仅在一个轴上定向，MAF矢量可以分解为两个场矢量，一个 沿一个轴方向，另一个轴沿垂直于第一轴的方向。最好的，以及 也许是确保 NMR 质量场指向 54.74o 角度的最简单方法 距磁体轴（也是旋转轴）的距离是为了独立确保 NMR 质量 由包含MAF磁体的每个线圈产生的磁场。这是我们的关键 构建成功的超导 MAF 磁体的创新设计理念： 轴向 z 轴场螺线管线圈和 x 轴场偶极子线圈的组合，每个 产生特定强度的 NMR 质量场。通过调整每个线圈的磁场 强度，我们将能够使用第一阶段磁铁实现磁场的两个要求 强度（此处为 1.5 T）和角度（54.74o）。借助这块磁铁，MAS 首次 NMR/MRI 科学将拥有超导 MAF 磁体，可产生 NMR- 具有显着强度的质量场，例如 1.5 T >> 36 高斯（UC 的先前最高值） 伯克利集团），以持久模式运行。另一个值得注意的意义是 创新的低温设计应用于该磁体（也用于第二阶段）。反而 在液氦 (LHe) 浴中操作时，磁体将浸入固体中 氮气 (SN2)。 （在第 2 阶段，磁铁将被安置在低温恒温器中，该低温恒温器将以 6 Hz.）这种全固体冷体改善了与 LHe 相关的热流体问题 旋转。而且，冷体中SN2的存在不仅保证了更均匀的 整个绕组的温度，而且还提供了大的热质量，使 即使主要磁体在一段时间内保持其工作磁场 冷却源（第一阶段的 LHe）关闭。综上所述，顺利完成了 这个两阶段计划将为 MAS NMR/MRI 科学带来新的机遇， 将为现代仪器分析开辟新途径，最终带来新颖的结果 用于分析、诊断和疾病预防的非侵入性生物医学工具。

项目成果

Magic-Angle-Spinning NMR Magnet Development: Field Analysis and Prototypes.

魔角旋转核磁共振磁体开发：现场分析和原型。

• DOI: 10.1109/tasc.2013.2245934
• 发表时间: 2013
• 期刊: IEEE transactions on applied superconductivity : a publication of the IEEE Superconductivity Committee
• 作者: Voccio,John;Hahn,Seungyong;Park,DongKeun;Ling,Jiayin;Kim,Youngjae;Bascuñán,Juan;Iwasa,Yukikazu
• 通讯作者: Iwasa,Yukikazu

A 1.5-T Magic-Angle Spinning NMR Magnet: 4.2-K Performance and Field Mapping Test Results.

1.5-T 魔角旋转 NMR 磁体：4.2-K 性能和场映射测试结果。

• DOI: 10.1109/tasc.2014.2375892
• 发表时间: 2015
• 期刊: IEEE transactions on applied superconductivity : a publication of the IEEE Superconductivity Committee
• 作者: Voccio,John;Hahn,Seungyong;Kim,Youngjae;Song,Jungbin;Kajikawa,Kazuhiro;Noguchi,So;Bascuñán,Juan;Iwasa,Yukikazu
• 通讯作者: Iwasa,Yukikazu