{
  "$type": "site.standard.document",
  "description": "A high-temperature NOx trap for trapping NOx in a lean condition in a high temperature range is so located as to trap NOx released from a low-temperature NOx trap for trapping NOx in the lean exhaust condition in a low temperature range. A sensor is provided for monitoring an NOx release condition…",
  "path": "/patents/1100414",
  "publishedAt": "2002-11-13T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "B01D53/9495",
    "NISSAN MOTOR [JP]"
  ],
  "textContent": "A high-temperature NOx trap for trapping NOx in a lean condition in a high temperature range is so located as to trap NOx released from a low-temperature NOx trap for trapping NOx in the lean exhaust condition in a low temperature range. A sensor is provided for monitoring an NOx release condition of the low-temperature NOx trap. A controller controls the exhaust air-fuel ratio of an engine to a lean side during the release of NOx from the low-temperature NOx trap, and controls the exhaust air-fuel ratio to a rich side temporarily after the release of NOx from the low-temperature NOx trap.",
  "title": "Exhaust gas purification system and method for internal combustion engine"
}