Speaker
Mr
Renzhong Piao
(Graduate School of Engineering, Chiba University)
Description
We have started a project to develop a high field compact NMR magnet using high-temperature superconducting (HTS) inner coils. As a first step towards such a magnet, a LTS/REBCO NMR magnet was developed and operated at 400 MHz (9.39 T) in a previous work [1]. However, a homogeneous magnetic field required for high-resolution NMR measurements could not be obtained using conventional field correction methods, due to an effect of a screening current induced in the inner REBCO coil. The REBCO coil had large field error harmonics; performance of a superconducting shim (SC) coils were remarkably reduced due to the diamagnetic effect of the REBCO coil, resulting in a residual field error harmonics.
In the present work, we operated the magnet with the best mix of field correction methods including a newly installed inner-SC shim coil and ferromagnetic shims in combination with conventional SC shim coils and room temperature (RT) shim coils. Major field error harmonics, which could not be corrected in the previous experiment, were successfully corrected; then higher-order field error harmonics generated by the ferromagnetic shims as a side effect, and lower-order harmonics due to a magnetization of the NMR probe and a sample were fully corrected using the RT shim coils. Eventually, a high-resolution 2D-NOESY NMR measurement for a protein solution sample, which is inevitable for structural biology, was successfully achieved. The field correction method achieved here is promising for a super-high field compact NMR magnet with HTS coils operated beyond 1 GHz (23.5 T).
[1]Y. Yanagisawa et. al., Journal of Magnetic Resonance, 249, 38-48 (2014).
Author
Mr
Renzhong Piao
(Graduate School of Engineering, Chiba University)
Co-authors
Dr
Hideaki Maeda
(Center for Life Science Technologies, RIKEN)
Mr
Hiroto Suematsu
(JEOL RESONANCE Inc.)
Dr
Mamoru Hamada
(Japan Superconductor Technology, Inc.)
Dr
Masato Takahashi
(Center for Life Science Technologies, RIKEN)
Prof.
Nakagome Hideki
(Graduate School of Engineering, Chiba University)
Mr
Seiya Iguchi
(Faculty of Science and Technology, Sophia University)
Dr
Shinji Matsumoto
(National Institute for Materials Sciences)
Prof.
Tomoaki Takao
(Faculty of Science and Technology, Sophia University)
Dr
Xinzhe Jin
(Center for Life Science Technologies, RIKEN)
Dr
Yoshinori Yanagisawa
(Center for Life Science Technologies, RIKEN)
