Hashi Kenjiro, Ohki Shinobu, Matsumoto Shinji, Nishijima Gen, Goto Atsushi, Deguchi Kenzo, Yamada Kazuhiko, Noguchi Takashi, Sakai Shuji, Takahashi Masato, Yanagisawa Yoshinori, Iguchi Seiya, Yamazaki Toshio, Maeda Hideaki, Tanaka Ryoji, Nemoto Takahiro, Suematsu Hiroto, Miki Takashi, Saito Kazuyoshi, Shimizu Tadashi
National Institute for Materials Science, 3-13 Sakura, Tsukuba 305-0003, Japan.
National Institute for Materials Science, 3-13 Sakura, Tsukuba 305-0003, Japan.
J Magn Reson. 2015 Jul;256:30-33. doi: 10.1016/j.jmr.2015.04.009. Epub 2015 May 7.
We have successfully developed a 1020MHz (24.0T) NMR magnet, establishing the world's highest magnetic field in high resolution NMR superconducting magnets. The magnet is a series connection of LTS (low-Tc superconductors NbTi and Nb3Sn) outer coils and an HTS (high-Tc superconductor, Bi-2223) innermost coil, being operated at superfluid liquid helium temperature such as around 1.8K and in a driven-mode by an external DC power supply. The drift of the magnetic field was initially ±0.8ppm/10h without the (2)H lock operation; it was then stabilized to be less than 1ppb/10h by using an NMR internal lock operation. The full-width at half maximum of a (1)H spectrum taken for 1% CHCl3 in acetone-d6 was as low as 0.7Hz (0.7ppb), which was sufficient for solution NMR. On the contrary, the temporal field stability under the external lock operation for solid-state NMR was 170ppb/10h, sufficient for NMR measurements for quadrupolar nuclei such as (17)O; a (17)O NMR measurement for labeled tri-peptide clearly demonstrated the effect of high magnetic field on solid-state NMR spectra.
我们成功开发了一台1020MHz（24.0T）的核磁共振磁体，创造了高分辨率核磁共振超导磁体的世界最高磁场。该磁体由低温超导（LTS，低临界温度超导体NbTi和Nb3Sn）外线圈与高温超导（HTS，高临界温度超导体Bi-2223）最内线圈串联组成，在超流液氦温度（如1.8K左右）下运行，并由外部直流电源以驱动模式运行。在未进行（2）H锁定操作时，磁场漂移最初为±0.8ppm/10小时；通过使用核磁共振内部锁定操作，磁场漂移随后稳定至小于1ppb/10小时。在氘代丙酮中1% CHCl3的（1）H谱半高宽低至0.7Hz（0.7ppb），这对于溶液核磁共振来说已足够。相反，在外部锁定操作下固态核磁共振的时间场稳定性为170ppb/10小时，这对于诸如（17）O等四极核的核磁共振测量来说已足够；对标记三肽的（17）O核磁共振测量清楚地展示了高磁场对固态核磁共振谱的影响。
