Abstract: A bipolar fluid flow flied plate for a fuel cell delivers fuel to a porous anode electrode and oxidant to an adjacent porous cathode electrode. The flow field plate comprises an electrically conductive, non-porous sheet into which fluid flow conduits are formed. A first fluid flow channel is patterned into a first face of the sheet and a second fluid flow channel patterned into the opposite face of the sheet. The pattern of the first channel comprises an interdigitated comb that co-operates with a pattern of the second channel comprising a continous serpentine path, so that no portion of the first channel directly overlies the pattern of the second channel over a substantial active area of the sheet. This allows the channels to be formed with combined depths that exceed the total plate thickness, thereby increasing fluid flow volumes.

Abstract: A fuel cell having an anode, a cathode and an ion exchange membrane is supplied by hydrogen fuel through an anode fuel delivery conduit. A recirculation loop is provided to recycle gases in the fuel delivery conduit to a mixing point where a controlled flow rate of fuel is supplied and mixed therewith. Any oxidant species remaining in the fuel delivery conduit are thereby combusted in a controlled manner to avoid damage to the fuel cell membrane-electrode assembly. Small quantities of oxidant may be deliberately introduced into the fuel delivery conduit to generate water vapor and heat to pre-condition the fuel delivered to the anode. Such preconditioning assists in hydration control of the membrane, and temperature control of the membrane-electrode assembly for optimum fuel cell performance.

Abstract: An apparatus for transferring television pictures onto cine film which operates independent of field scan frequency and which synchronizes each frame of the cine film with the television field scans to avoid the appearance of a bar across each frame. The apparatus comprises a cine camera which in operation is placed in front of a television screen and which generates a shutter opening signal, a control unit which synchronizes that signal with the video signal to the television such that the shutter opens at the beginning of a field scan, and a motor drive unit which utilizes the video signal to drive the camera shutter blade at one third the field scan frequency. The apparatus is useful for transferring television field scans operating at any frequency onto cine film.