Abstract: A water activated primary battery in which each cell includes a cathode manufactured largely from an oxy-halogen material and an anode of aluminum, magnesium, zinc or alloys thereof, the electrodes being separated and insulated from one another by a porous membrane; the main feature of the invention being the sandwich construction of the cells and design of the anode which is perforated to provide access of the electrolyte to the cathode and escape of gas from the cell and dimpled to facilitate uniform compaction of the cathode material and to provide cooling water/electrolyte passageways in each cell.

Abstract: A single three-electrode linear detector replaces the conventional series or parallel linear detector array in a scanned image thermal detection system. The detector comprises an elongated semiconductor/photoconductor strip, typically 0.25 cm long and 50 .mu.m wide, e.g., of cadmium mercury telluride. A bias current in the strip is arranged to give a photocarrier drift velocity in the strip which matches the image scanning velocity thereby giving enhanced image resolution. Modulation in photocarrier current which constitutes the detected image is measured as a bulk resistivity change between two readout electrodes positioned near one end of the strip.

Abstract: A multiple re-entry compressor of the kind set forth in USA Patent application Ser. No. 335,162 now U.S. Pat. No. 3,869,220 is described having inter cooling between successive passes of the rotor blading. A further improvement is described in which variable aperture arcuate segmented flowpaths are provided.

Abstract: The noise in a crossed field amplifier output is reduced by providing a non-uniform magnetic field across the surface of the cathode. This may be achieved by providing a curved magnetic field across the cathode or by providing a concave shaped cathode. Additionally the cathode may be tilted with respect to the cross magnetic field.

Abstract: A transmission photocathode comprising a crystal substrate transparent to the radiation to be detected, at least one epitaxial crystalline intermediate layer having a lattice constant close to that of the detector layer and transparent to the radiation to be detected, and a p-type group III-V compound detector layer. Preferably the intermediate layer is p-type.

Abstract: The evaporation of metal for the production of alloys by the deposition of the components from the vapour phase is carried out in a controllably heated source comprising a melting compartment, in which in operation the metal is melted; a mixing compartment, a constriction in the passage from the melting to the mixing compartment to minimise back mixing of the molten metal, and an evaporation compartment, the supply of metal from the mixing compartment to the evaporation compartment being below the surface of the molten metal. Heating is preferably by electron beam heating.