We are currently working on a program to complete a 1.5-T/75-mm RT (room temperature) bore MAS (magic-angle-spinning) NMR (nuclear magnetic resonance) magnet. The MAS magnet comprises a z-axis 0.866-T solenoid and an x-axis 1.225-T dipole coil. The combination of the fields creates a 1.5-T field pointed at 54.74 degrees (magic angle) from the rotation (z) axis. During the 2nd year of this 3-year Phase I program, both coils have been wound and testing has begun. Some preliminary field mapping has been performed, and the design of the MAS magnet assembly has been completed. During the final year, the magnet assembly will be integrated into the cryogenic structure and tested at ~ 5.5 K in a solid nitrogen environment. Each coil will be energized separately, and the magnetic field will be mapped accurately. We expect a bare magnet uniformity of 100 ppm over a 10-mm diameter, 20-mm-long cylindrical volume. Then, using the field data, the uniformity will be improved to 0.1.ppm with a combination of ferroshims and cryoshims. Final field measurement will be performed as the cryostat-magnet system is spun manually at ~0.1 Hz.

中文翻译：

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1.5-T/75-mm Magic-Angle-Spinning NMR Magnet

我们目前正在制定一项计划，以完成 1.5-T/75-mm RT（室温）内径 MAS（魔角旋转）NMR（核磁共振）磁体。MAS 磁体包括一个 z 轴 0.866-T 螺线管和一个 x 轴 1.225-T 偶极线圈。场的组合创建了一个 1.5-T 场，指向与旋转 (z) 轴成 54.74 度（魔角）。在这个为期 3 年的第一阶段计划的第 2 年期间，两个线圈都已绕好并开始测试。已经进行了一些初步的场映射，并完成了 MAS 磁体组件的设计。在最后一年，磁铁组件将集成到低温结构中，并在固态氮环境中以 ~ 5.5 K 进行测试。每个线圈将单独通电，并准确映射磁场。我们预计在 10 毫米直径、20 毫米长的圆柱形体积上的裸磁均匀性为 100 ppm。然后，使用现场数据，使用铁垫片和冷冻垫片的组合将均匀性提高到 0.1.ppm。当低温恒温器-磁铁系统以 ~0.1 Hz 手动旋转时，将执行最终场测量。