| 摘要 |
A reactor (8) for treating an exhaust gas comprises at least one first zone (16, 18) and a second zone (20) downstream of the or each first zone, the or each first zone and optionally the second zone including a chemically active coating or a catalytically active coating. The or each first zone includes a region (24): (a) that is substantially free of active coating whereby, when the reactor is included in an exhaust system including a means (14) for supplying a reactant upstream of the or each first zone, a reactant flowing over the region can pass thereover substantially without reacting so that the reactant can reach the second zone; or (b) the reactor (8) is included in an exhaust system comprising a means (14) for supplying a reactant upstream of the or each first zone (16, 18), the arrangement being such that the supply means (30) substantially prevents access of the exhaust gas to a region (28) of the or each first zone whereby a reactant introduced into the region via the supply means can pass through the or each first zone to reach the second zone without reacting with components in the exhaust gas. |
