a hydrogen sensitive dye disposed in or placed on said container, said hydrogen sensitive dye outputting a detectable signal in {HEAD ~ response} to a presence or {TAIL ~ absence} of said molecular hydrogen 
a hydrogen sensitive dye disposed in or placed on said container , said hydrogen sensitive dye outputting a detectable signal in { HEAD ~ response } to a presence or { TAIL ~ absence } of said molecular hydrogen
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH