| 摘要 |
<p>In a cryostat composed of a first liquefied gas reservoir containing therein a first liquefied gas, a second liquefied gas reservoir containing therein a second liquefied gas, which has a boiling point higher than that of the first liquefied gas, the second liquefied gas reservoir being provided around the first liquefied reservoir in order to reduce the heat leak into the first liquefied gas reservoir, and an outer wall surrounding the second liquefied gas reservoir through a vacuum space, a refrigerating machine is arranged in the space within the outer wall and cools the second liquefied gas in the second and first liquefied gas reservoirs and the first liquefied gas whereby the cryostat may be used continuously for a long period of time without periodically supplying the second and third gases.</p> |
