{
  "$type": "site.standard.document",
  "description": "A NOx occluding member (23) that occludes NOx when the air-fuel ratio is on the fuel-lean side is disposed in an engine exhaust passage. An NOx ammonia sensor (29) is disposed in the engine exhaust passage downstream of the NOx occluding member (23). A surplus amount of a reducing agent that is not…",
  "path": "/patents/1078855",
  "publishedAt": "2005-04-06T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "F01N13/009",
    "TOYOTA MOTOR CO LTD [JP]"
  ],
  "textContent": "A NOx occluding member (23) that occludes NOx when the air-fuel ratio is on the fuel-lean side is disposed in an engine exhaust passage. An NOx ammonia sensor (29) is disposed in the engine exhaust passage downstream of the NOx occluding member (23). A surplus amount of a reducing agent that is not used to release NOx is determined from a change in the ammonia concentration detected by the NOx ammonia sensor (29) when the air-fuel ratio is changed to the fuel-rich side so as to release the NOx from the NOx occluding member (23).",
  "title": "Emission control apparatus of internal combustion engine"
}