| 摘要 |
PROBLEM TO BE SOLVED: To provide means for applying a high frequency magnetic field having large strength to a sample in NMR measurement.SOLUTION: A high frequency magnetic field shielding apparatus formed with an electric good conductor in external peripheral surface is installed inside a measurement coil which generates the high frequency magnetic field. The high frequency magnetic field shielding apparatus has a uniform cross-section when cut at a plane perpendicular to a central axis of the measurement coil while moving along the central axis. The sample is set in a space between the internal surface of the measurement coil and the external peripheral surface of the high frequency magnetic field shielding apparatus. If the current flowing through the measurement coil is constant, all magnetic fluxes are constant, but since the magnetic fluxes are unable to infiltrate into the high frequency magnetic field shielding apparatus, magnetic flux density of the high frequency magnetic field in the residual space is increased. Thereby, high frequency magnetic field strength can be increased and a filling rate of the sample can be improved. |
