Abstract: A superconducting lead comprises a supporting board (1) with at least one superconducting tape (3) adhered to it and extending from one terminal area of the lead to another. Respective metal end-fittings soldered to the superconducting tape (3) at each of its ends, and in each of the terminal areas at least one metal insert is bonded to the board (1) and also soldered to the corresponding one of the said end-fittings, so relieving the tapes (3) of mechanical stress. The board (1), or each of them, is preferably flat and may support two or more superconducting tapes (3) coplanar with one another on one or on each of its major faces. The metal inserts are preferably of copper and may be made by removing most of the copper cladding from a commercially available circuit board (1).

Abstract: An improved boiler for liquefied gases comprises at least one heat transfer surface having means for creating a falling film of liquefied gas from its upper to lower end and means to heat the surface above the temperature at which the liquefied gas boils at the prevailing pressure. The subject apparatus is particularly suited for reboiling liquid nitrogen or liquid oxygen.

Abstract: A heat exchanger has a plurality of main flow passages 2 for cooling fluid. Each main flow passage has associated with it at least one narrow channel 10 defined by a surface of the main flow passage and an auxiliary surface on a separator plate 8. Relatively hot fluid flows over the separator plate 8 and heats the auxiliary surface such that bubbles formed in the channel are flattened by the surface opposite to the auxiliary surface and pressed against the auxiliary surface. The bubbles eventually pass through holes 12 in the channel 10 into the main flow passage 2 to rejoin the evaporating liquid pool.