| 摘要 |
A siphon for delivery of a liquid cryogen from a container such as a Dewar flask. The siphon ensures delivery of a liquid cryogen with a lower proportion of the gaseous fraction. The siphon comprises a central feeding conduit, which is largely contained within the Dewar flask. There is an auxiliary conduit surrounding the central feeding conduit; the outer upper section of this auxiliary conduit is provided with an adjustable valve intended to release a gaseous fraction of the cryogen contained in the annular gap between the auxiliary and central feeding conduits. The upper section of the central feeding conduit is provided with an external layer of a porous capillary coating or with a wick; this ensures that the upper section of the central feeding conduit is continuously wetted with the liquid cryogen. This porous capillary coating prevents gasification of the liquid cryogen in the central feeding conduit. Alternatively, the problem of liquid cryogen gasification may be solved through thermal insulation of the central feeding conduit.
|
