| 摘要 |
<p>1396507 Refrigerating BRITISH OXYGEN CO Ltd 23 Aug 1972 [27 Aug 1971] 40356/71 Heading F4H A cryostat for controlling the temperature of a sample 43 in an inner vessel 2 has an evacuated space 10 between the vessel 2 and an outer vessel 4 which vessel 4 is partially immersed in a cryogenic liquid bath 44, e.g. liquid helium, the helium passing from the bath via a capillary tube 28 and a sintered copper or like heat exchanger 40 to the inner vessel and the generated vapour is exhausted from the inner vessel through a conduit 20 having a flow control valve 26. An electrical heater (not shown) is located within the lower part 34 of the inner vessel which is used for raising the temperature of the chamber 42, the helium flowing through the chamber being warmed and its flow is restricted by valve 26.</p> |
