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A high-resolution 1.3-GHz LTS/HTS NMR magnet (1.3G)

高分辨率 1.3 GHz LTS/HTS NMR 磁体 (1.3G)

基本信息

批准号：
10675082
负责人：
Yukikazu Iwasa
金额：
$ 55.91万
依托单位：
MASSACHUSETTS INSTITUTE OF TECHNOLOGY
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-01 至 2024-07-30
项目状态：
已结题

项目摘要

In the simplest view of NMR, the advantages of higher field (B0) are improved sensitivity and resolution. For NMR spectroscopy, sensitivity and resolution depend, respectively, on amplitude and frequency of measurement. Sensitivity per unit time in signal averaging experiments and resolution for 3D experiments both ideally improve as ω3 and, hence, B03. Thus, increased proton frequency, for example, from 900 MHz, currently the highest frequency at the MIT-Harvard Magnetic Resonance Center, to 1.3 GHz, increases sensitivity and resolution by a factor of 3. This benefit of higher frequency was the basis of our initiative in 2000 to propose a long march towards a 1-GHz NMR magnet by combining low- and high-temperature superconducting magnets, LTS and HTS; in 2007 the proposed frequency was increased to 1.3 GHz. HTS is mandatory at frequencies above 1-GHz, thus, our 1.3-GHz LTS/HTS NMR magnet (1.3G) combines a 500-MHz LTS NMR magnet (L500) with an 800-MHz HTS insert (H800). HTS conductors are used in this 4K application not for their high- temperature capabilities, but rather for their ability to achieve significantly higher magnetic field than can be reached by LTS alone. Despite the best efforts in design and construction, the homogeneity of an “as-wound” NMR magnet in reality will be more than two orders of magnitude away from required specifications. For field shimming, another critical activity in this Revised Phase 3BZ is field mapping, requiring exact probe positioning along optimized path and accurate measurement, from which to derive the target field gradients that in turn guide the design of appropriate shim coils, in our case, of HTS and room-temperature (RT), both to be designed and built in this Revised Phase 3BZ. Because HTS insert is notorious as a source of “large” non- uniform field, field shimming our 1.3G will be challenging and laborious, requiring innovative ideas. The specific aims (SA) of the last phase of this MIT 1.3-GHz LTS/HTS NMR magnet that began in 2000 are to achieve two vital requirements for NMR. In the first two years, we will: 1) replace the H800 damaged in March 2018 test with a new 800-MHz HTS insert (H800N) and 2) combine L500 and H800N to complete a new non-NMR 30.5- T L500/H800N magnet; and in the last two years we will 3) convert the non-NMR 30.5-T field to realize a high- resolution 1.3 GHz NMR magnet (1.3G). To achieve SA3, we will apply two innovative techniques: 1) HTS Z1 and Z2 shim coils, installed in the bore of H800N; and 2) current-sweep-reversal and field-shaking to mitigate the screening-current field (SCF), a non-uniform diamagnetic field, superposed on the main field that severely degrades the spatial field quality particularly for HTS magnets like our H800N. We will also deploy ferro- magnetic passive shimming and RT active shimming, both of our design. We believe that our 1.3G will become a vital force in high-field NMR as well as for drug discovery and development; it will serve the entire U.S. NMR community for decades to come and have a worldwide impact on biomedical sciences. We also believe that our 1.3G will become a model for high-resolution >1-GHz NMR magnets that must incorporate HTS inserts.

在NMR的最简单的观点中，更高场（B 0）的优点是提高灵敏度和分辨率。为核磁共振波谱，灵敏度和分辨率分别取决于振幅和频率，测量.信号平均实验中的单位时间灵敏度和3D实验的分辨率理想地改进为ω3且因此改进为B 03。因此，增加的质子频率，例如，从目前的900 MHz，麻省理工-哈佛磁共振中心的最高频率为1.3 GHz，提高了灵敏度，分辨率为3倍。我们在2000年提出了一项倡议，通过结合低温和高温超导磁体，向1-GHz NMR磁体的长征， LTS和HTS; 2007年，提议的频率增加到1.3 GHz。HTS是强制性的频率因此，我们的1.3 GHz LTS/HTS NMR磁体（1.3G）结合了500 MHz LTS NMR磁体（L500）与800-MHz HTS插入物（H800）。HTS导体用于这种4K应用中，不是因为它们的高- 温度能力，而是它们实现比可以实现的磁场显著更高的磁场的能力。仅限于LTS。尽管在设计和构造上尽了最大的努力，核磁共振磁铁在现实中将超过两个数量级远离所需的规格。主管外勤匀场，此修订的第3BZ阶段中的另一项关键活动是场标测，需要精确的探头定位沿着优化的路径和精确的测量，从中推导出目标场梯度，指导设计适当的匀场线圈，在我们的情况下，高温超导和室温（RT），都是设计和建造于此修订的3BZ期。因为HTS插入物作为“大”非- 统一的领域，场匀场我们的1.3G将是具有挑战性的和艰苦的，需要创新的想法。具体 2000年开始的麻省理工学院1.3 GHz LTS/HTS NMR磁体的最后阶段的目标（SA）是实现两个对NMR的重要要求。在前两年，我们将：1）更换在2018年3月测试中损坏的H800 使用新的800-MHz HTS插入物（H800 N）和2）联合收割机L500和H800 N以完成新的非NMR 30.5- T L500/H800 N磁体;在过去的两年中，我们将3）转换非NMR 30.5-T场，以实现高- 分辨率1.3 GHz NMR磁体（1.3G）。为了实现SA 3，我们将应用两种创新技术：1）HTS Z1 和Z2匀场线圈，安装在H800 N的孔中;和2）电流扫描反向和场震动，以减轻屏蔽电流场（SCF）是一种非均匀抗磁场，叠加在主磁场上，降低了空间磁场质量，特别是对于像我们的H800 N这样的高温超导磁体。我们还将部署铁- 磁被动匀场和RT主动匀场，我们的设计。我们相信我们的1.3G将会成为高场NMR以及药物发现和开发的重要力量;它将服务于整个美国NMR 在未来几十年里，它将对生物医学科学产生全球影响。我们也相信我们的1.3G将成为高分辨率>1 GHz NMR磁体的典范，这些磁体必须包含HTS插入物。

项目成果

期刊论文数量（43）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Prototype REBCO Z1 and Z2 shim coils for ultra high-field.

用于超高场的 REBCO Z1 和 Z2 匀场线圈原型。

DOI：
10.1038/s41598-020-78644-0
发表时间：
2020-12-15
期刊：
Scientific reports
影响因子：
4.6
作者：
Park D;Lee J;Bascuñán J;Li Z;Iwasa Y
通讯作者：
Iwasa Y

Partial-Insulation HTS Magnet for Reduction of Quench-Induced Peak Currents.

部分绝缘高温超导磁体，用于减少淬火引起的峰值电流。

DOI：
10.1109/tasc.2022.3156064
发表时间：
2022
期刊：
IEEE transactions on applied superconductivity : a publication of the IEEE Superconductivity Committee
影响因子：
0
作者：
Lee,Wooseung;Park,Dongkeun;Bascuñán,Juan;Iwasa,Yukikazu
通讯作者：
Iwasa,Yukikazu

Self-Protection Characteristic Comparison between No-Insulation, Metal-as-Insulation, and Surface-Shunted-Metal-as-Insulation REBCO coils.

无绝缘、金属绝缘和表面分流金属绝缘 REBCO 线圈的自保护特性比较。

DOI：
10.1109/tasc.2023.3267727
发表时间：
2023
期刊：
IEEE transactions on applied superconductivity : a publication of the IEEE Superconductivity Committee
影响因子：
0
作者：
Kim,Junseong;Park,Dongkeun;Dong,Fangliang;Lanzrath,Andrew;Lee,Wooseung;Bascuñán,Juan;Iwasa,Yukikazu
通讯作者：
Iwasa,Yukikazu

Experimental and Numerical Studies on a Method to Mitigate Screening Current-Induced Field for No-Insulation REBCO Coils.

针对无绝缘 REBCO 线圈减轻屏蔽电流感应场的方法的实验和数值研究。

DOI：
10.1109/tasc.2019.2906221
发表时间：
2019
期刊：
IEEE transactions on applied superconductivity : a publication of the IEEE Superconductivity Committee
影响因子：
0
作者：
Lee,Jiho;Park,Dongkeun;Li,Yi;Choi,YoonHyuck;Michael,PhilipC;Bascuñân,Juan;Iwasa,Yukikazu
通讯作者：
Iwasa,Yukikazu

Persistent-current switch for pancake coils of rare earth-barium-copper-oxide high-temperature superconductor: Design and test results of a double-pancake coil operated in liquid nitrogen (77-65 K) and in solid nitrogen (60-57 K).