About: http://webisa.webdatacommons.org/341674883

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	Such a diaphragm may be constructed from alumi- 'num or; aluminum alloy sheet about .0035 em. . thick, the central portion being embossed in conical or other form to ive rigidity.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com