About: http://webisa.webdatacommons.org/414643147

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	Preferable that NO gas is mixed with a balance or carrier gas such as nitrogen and the concentration may be in the order of 100 ppm.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com