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

此分两个阶段的计划的第一阶段有两个具体目标：1)成功完成 磁场强度显著的魔角场(MAF)磁体，具有核磁共振质量场 慢速MAS(魔角旋转)磁共振/核磁共振的均匀性；以及2)应用和 用建议的系统演示一种适用于 一种超导磁体，在第一阶段缓慢旋转(约0.1赫兹)，在第二阶段以6赫兹旋转。 与传统的核磁共振或核磁共振磁体不同的是，磁体具有核磁共振质量的场矢量 MAF向量只指向一个轴，可以分解成两个场向量，一个 指向一个轴，另一个指向垂直于第一个轴的方向。最好的，而且 也许最简单的方法是确保以54.74度的角度定向的核磁共振质量场 从磁体轴(也就是旋转轴)来独立保证核磁共振质量 由构成MAF磁铁的每个线圈产生的磁场。这是我们的关键所在 成功建造超导磁铁的创新设计理念：A 轴向z-场螺线管线圈和x轴场偶极线圈的组合，每个 产生特定强度的核磁共振质量场。通过调整每个线圈的磁场 实力，我们将能够达到这一阶段磁铁的两个领域的要求 强度(这里是1.5T)和角度(54.74o)。有了这块磁铁，MAS第一次 核磁共振/核磁共振科学将有一个超导磁铁来产生核磁共振- 具有显著实力的质量领域，例如1.5 T&>&36 Gauss(UC之前的最高值 伯克利集团)，以持续模式运行。另一个值得注意的意义是 创新的低温设计应用于这种磁铁(也用于第二阶段)。取而代之的是 如果在液氦(LHe)浴中操作，磁体就会浸入固体中 氮素(SN2)。(在第二阶段，磁铁将被安置在低温恒温器中，该恒温器将以6 赫兹。)这种全固态冷体改善了与LHe有关的热流体问题 旋转。此外，SN2在冷体中的存在不仅确保了更均匀的 整个绕组的温度也提供了很大的热量，使得 磁体在一段时间内保持其作业场，即使在主要 关闭冷却源(一期LHe)。总而言之，圆满完成 这一分两个阶段的计划将在MAS核磁共振/核磁共振科学领域开辟新的机遇，在 TURN将为现代工具分析开辟新的途径，最终导致小说 用于分析、诊断和疾病预防的非侵入性生物医学工具。

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.