摘要 |
An improved catalytic substrate for use with a can in an automotive exhaust system, the substrate being of the type which is disposed in use in the can, the improvement comprising: an insulation material thermally separating the substrate into a central zone and a tubular outer zone surrounding the central zone, the insulation material, central zone and outer zone collectively defining a modified substrate, the insulation material being adapted such that, in an operating condition, the temperature difference across the insulation material is at least 25° C. |