Abstract: Aspects of managing fluid diffusion across active regions of one or more of a cathode and anode are disclosed herein, aspects include a method of efficient fluid distribution within an MEA (20) by forming a fluid confinement space with a sealing gasket (50) forming placed on at least one of an anode and a cathode of a fuel cell the gasket configured with at least one inlet (140) fluidly communicating with the fluid containment space and at least one outlet (145) through the gasket (50) fluidly communicating with the fluid containment space, inserting a generally planar rectangular porous gas diffusion layer (40) with two end walls, and two side walls, configured to fit form at least one inlet plenum (186) is formed around at least one edge of the gas diffusion layer (40) and an annular wall of the fluid confinement space and one outlet plenum (188) and, the resistance to fluid flow along the inlet plenum (186) is balanced against the resistance to fluid flow across the gas diffusion insert configured to urge

Abstract: A device 1, capable of being placed in-line in the exhaust conduit of an IC engine upstream of an SCR catalyst, which produces a gaseous hydrolysis product, containing ammonia, which is added to the exhaust gas in a controlled manner to pass therewith through the SCR catalyst to reduce the NOx content of the exhaust gas. The device 1 has an inlet 2 and an outlet 3 for the exhaust gas flowing therethrough and comprises an outer body 4, which forms a pressure barrier, and passing through the outer body 4 is an inner body 5 which comprises a flowpath longitudinally therethrough from the inlet 2 to the outlet 3.