About: http://webisa.webdatacommons.org/168712201

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	Difficulties have been encountered in the heat sealing of polyethylene films by means of a hot iron when impurities, such as water or grease, were on the faces of the polyethylene film along the line at which a seam was to be made.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com