Abstract: The bipolar plate is thinner because it includes in a single plane all of the channels (21) for circulation of the oxidiser, the fuel and the coolant fluid (41). The feed plate, which is preferably made of a composite material, has on each of its faces (1A, 1B) a network of channels for the circulation either of oxidiser or fuel, which are supplied through feed apertures (2, 3) passing through the plate. Refrigeration is achieved by means of feed apertures (4) feeding into one or more refrigeration channels (41) positioned between the parts of the circulation channels (21) for the oxidiser or the fuel. Possible through passages (43) allow these different channels to pass from one face to the other so as to organise the circulation and the removal of these three fluids. It is thus possible to distribute the oxidiser and the fuel to both sides of the plate, while also arranging its refrigeration. Application to fuel cells of average and high power.

Abstract: The two-pole plate is relatively lightweight and can be manufactured quickly and easily. It consists of a skeleton made with two thin plates (30) spaced by blocks (34, 45) between which a cooling fluid circulates. The fuel and oxidant manifolds supply the circulation channels (21I) machined by water jet in supply plates (20I, 20S) made of conducting composite, through the supply channels (33). These plates are bonded with a conducting glue onto the thin plates (30). Application to fuel cells.

Abstract: Three aqueous cleaning solutions are disclosed, which may be used individually or as part of a two-solution cleaning method for silver halide-based photographic processing systems. One solution comprises water, an organic or inorganic iron salt wherein the iron is in the +3 oxidation state, a chelating agent, and an organic or inorganic silver complexing agent. A second solution comprises water, an organic or inorganic acid or acid anhydride, a surfactant, and a water soluble solvent. A third solution comprises water, a chelating agent, an alkali metal silicate salt, a surfactant, and a water soluble solvent.