Study of Cu-wound Flux transformer for High-Tc SQUID Ultra-Low Field MRI

11th European Conference on Applied Superconductivity

Tanaka, S.^1 ; Murata, H.^1 ; Imamura, K.^1 ; Hatsukade, Y.^1

Department of Environmental and Life Sciences, Toyohashi University of Technology, 1-1 Hibarigaoka, Tenpaku-cho, Aichi, Toyohashi

441-8580, Japan^1

关键词: Flux transformers;    Free induction decay signals (FID);    Longitudinal relaxation;    Measurement field;    Nuclear Magnetic Resonance (NMR);    Polarizing fields;    Ultra-low field;    Ultra-low-field mris;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/507/4/042042/pdf
DOI  :  10.1088/1742-6596/507/4/042042

来源: IOP

【 摘 要 】

We constructed a ultra-low field (ULF) nuclear magnetic resonance (NMR) / magnetic resonance imaging (MRI) system employing a high-temperature superconductor (High Tc) SQUID with a separated Cu-wound flux transformer. The pickup coil consisted of two single solenoid coils and each coil was differentially connected each other. The flux transformer consisted of a pickup coil at room temperature and an input coil, which was put in liquid nitrogen and was magnetically coupled with a high-Tc SQUID. The ratio of the transformer was considered and optimized. A water phantom of 10 mL was located in the one side of pickup coil. In the system, we applied polarizing field Bpperpendicular to the measurement field Bmbefore measurements. Bpwas 0.8 T and permanent magnet was used. By using this system, free induction decay (FID) signals of2H were measured at Bmof 30 μT to evaluate the system. The longitudinal relaxation times T1of water were also estimated by changing the polarizing time of Bp.