First-Cut Design of a Benchtop Cryogen-Free 23.5-T/25-mm Magnet for 1-GHz Microcoil NMR.
First-Cut Design of a Benchtop Cryogen-Free 23.5-T/25-mm Magnet for 1-GHz Microcoil NMR.
复制标题
用于 1 GHz 微线圈 NMR 的台式无冷冻剂 23.5-T/25-mm 磁体的首次设计。
DOI：
10.1109/tasc.2023.3252487
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发表时间：
2023
期刊：
影响因子：
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通讯作者：
Iwasa,Yukikazu
中科院分区：
文献类型：
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作者：
Park,Dongkeun;Dong,Fangliang;Lee,Wooseung;Bascuñán,Juan;Iwasa,Yukikazu
作为初步工作，我们已经完成了一个12.5 mm冷膛高温超导（HTS） REBCO磁体原型，并成功地将其在10 K下运行到25 T，仅通过制冷机冷却，没有液氦。在这篇文章中，我们展示了一个无低温的全rebco 23.5 t / 25mm暖孔磁铁的首次切割设计，在1厘米直径的球形体积上具有<0.1 ppm的高均匀性，用于台式1 ghz微线圈核磁共振波谱。我们还研究了将5高斯条纹场半径减小到≤1.5 m的屏蔽设计。这款台式磁体将整合所有经过原型磁体验证的创新设计和操作概念：1)全hts组成和在4.2 K以上的操作；2)无绝缘绕组技术，带有额外的分流，使这种高场REBCO磁铁紧凑，机械坚固，并具有自我保护功能；3)与传统的多嵌套高场核磁共振磁体相比，单线圈形成导致更简单和更经济的制造工艺；4)操作温控屏蔽电流减小方法，可减小REBCO线圈内的峰值应力和现场误差；5)传导冷却操作的低温设计。
As a preliminary work, we have completed a 12.5-mm-cold-bore high-temperature superconducting (HTS) REBCO magnet prototype and successfully operated it up to 25 T at 10 K cooled by a cryocooler only, without liquid helium. In this article we present the first-cut design of a cryogen-free all-REBCO 23.5-T/25-mm-warm-bore magnet having a high homogeneity of <0.1 ppm over a 1-cm diameter of spherical volume for a benchtop 1-GHz microcoil NMR spectroscopy. We also investigate a shielding design to reduce a 5-gauss fringe field radius to ≤1.5 m. This benchtop magnet will incorporate all the innovative design and operation concepts validated by the prototype magnet: 1) all-HTS composition and operation at above 4.2 K; 2) no-insulation winding technique with an extra shunting that makes this high-field REBCO magnet compact, mechanically robust, and self-protecting; 3) a single coil formation that leads, compared with the traditional multi-nested high-field NMR magnet, to simpler and more affordable manufacturing processes; 4) operational temperature-controlled screening-current reduction method which reduces peak stresses within the REBCO coil and field errors; and 5) cryogenic design for conduction-cooling operation.