A temperature sensor 42 is provided in a furnace 11, measuring temperature above a molten liquid 24 put in {HEAD ~ a crucible} 12 to check {TAIL ~ proceedings} of evaporation of oxygen vaporized from a free surface 44 of the molten liquid 24 
to check
A temperature sensor 42 is provided in a furnace 11 , measuring temperature above a molten liquid 24 put in { HEAD ~ a crucible } 12 to check { TAIL ~ proceedings } of evaporation of oxygen vaporized from a free surface 44 of the molten liquid 24
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 HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH