PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • In general, carbonaceous materials, such as coal or petroleum coke, can be converted to a plurality of gases, including value-added gases such as methane, by the gasification of the material in the presence of an alkali metal catalyst source and steam at elevated temperatures and pressures.
http://www.w3.org/ns/prov#wasQuotedFrom
  • google.com