{HEAD ~ An inert gas}, such as {TAIL ~ N2} is then blown over the coated substrate 
such as
{ HEAD ~ An inert gas } , such as { TAIL ~ N2 } is then blown over the coated substrate
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH