A substrate is provided within {TAIL ~ a reaction chamber}, and a mixture is also provided within {HEAD ~ the chamber} 
A substrate is provided within { TAIL ~ a reaction chamber } , and a mixture is also provided within { HEAD ~ the chamber }
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD