A method 1 wherein {HEAD ~ the oxygen content} of the gas is from {TAIL ~ about 1%} to about 100% 
is from
A method 1 wherein { HEAD ~ the oxygen content } of the gas is from { TAIL ~ about 1 % } to about 100 %
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH