About: http://webisa.webdatacommons.org/421252106

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Indeed, air is a mixture of gases, and certain components such as carbon dioxide have very low boiling points and are difficult to liquefy in cryogenic systems.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com