| 摘要 |
<p>A method and a device are provided to cool an oxide superconductor material using liquid nitrogen to a temperature lower than its boiling point. There are two kinds of cooling, i.e., cooling under reduced pressure and cooling under ordinary pressure. The reduced-pressure cooling device has a coil-accommodating chamber which is a reduced-pressure vessel. The pressure in the coil-accommodating chamber is reduced by a pressure-reducing pump, whereby the liquid nitrogen assumes a temperature of the triple point. The ordinary-pressure cooling device has a cooling portion of the refrigerator in the coil-accommodating chamber, and in which the liquid nitrogen is cooled down to its melting point.</p> |
