PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Preferably, the gas is an inert gas such as helium or argon to minimize both ionization of the atmosphere surrounding emitters 48 when the print head is in operation and formation of such harmful compounds as nitric acid from the oxidation of nitrogen.
http://www.w3.org/ns/prov#wasQuotedFrom
  • google.com