About: http://webisa.webdatacommons.org/37872669

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	A reference numeral 20 refers to a vacuum chamber included in the processing vessel, which is formed of a conductive material, such as aluminum, to have an airtight structure.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com