About: http://webisa.webdatacommons.org/236146049

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	Carbon black especially is thought to form SiC, which is difficult to remove. [0052] In the present invention, sulfur may be advantageously used as a pore former in the manufacture of photonic crystal preforms.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com