{HEAD ~ The catalyst solution} may include a dye or {TAIL ~ other colorimetric substance} for visualizing the layer of catalyst solution on the substrate 
include
{ HEAD ~ The catalyst solution } may include a dye or { TAIL ~ other colorimetric substance } for visualizing the layer of catalyst solution on the substrate
HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH