PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • It is also possible to obtain hydrogen by separating water in an electrolyzer, or by extracting it from a compound that contains no carbon, such as ammonia or boron compounds.
http://www.w3.org/ns/prov#wasQuotedFrom
  • altenergymag.com