title: Development of a superconducting bulk magnet for NMR and MRI.
abstract: A superconducting bulk magnet composed of six vertically stacked annular single-domain c-axis-oriented Eu-Ba-Cu-O crystals was energized to 4.74 T using a conventional superconducting magnet for high-resolution NMR spectroscopy. Shim coils, gradient coils, and radio frequency coils for high resolution NMR and MRI were installed in the 23 mm-diameter room-temperature bore of the bulk magnet. A 6.9 ppm peak-to-peak homogeneous region suitable for MRI was achieved in the central cylindrical region (6.2 mm diameter, 9.1 mm length) of the bulk magnet by using a single layer shim coil. A 21 Hz spectral resolution that can be used for high resolution NMR spectroscopy was obtained in the central cylindrical region (1.3 mm diameter, 4 mm length) of the bulk magnet by using a multichannel shim coil. A clear 3D MR image dataset of a chemically fixed mouse fetus with (50 μm)(3) voxel resolution was obtained in 5.5 h. We therefore concluded that the cryogen-free superconducting bulk magnet developed in this study is useful for high-resolution desktop NMR, MRI and mobile NMR device.
authors: RIKEN, Wako 351-0198, Japan.
authors: Takashi
authors: T
authors: Nakamura
authors: Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8573, Japan.
authors: Daiki
authors: D
authors: Tamada
authors: IMRA Material R&D Co., Ltd., Kariya 448-0021, Japan.
authors: Yousuke
authors: Y
authors: Yanagi
authors: IMRA Material R&D Co., Ltd., Kariya 448-0021, Japan.
authors: Yoshitaka
authors: Y
authors: Itoh
authors: JEOL Resonance, Akishima 196-8558, Japan.
authors: Takahiro
authors: T
authors: Nemoto
authors: JEOL Resonance, Akishima 196-8558, Japan.
authors: Hiroaki
authors: H
authors: Utumi
authors: Institute of Applied Physics, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8573, Japan. Electronic address: kose@bk.tsukuba.ac.jp.
authors: Katsumi
authors: K
authors: Kose
keywords: High temperature superconducting material; MRI; NMR; Shim coil; Superconducting bulk magnet