Each of the flow rates of {TAIL ~ the reactant gases} is accurately controlled by {HEAD ~ conventional, commercially available mass flow controllers}, such as those from Tylan Corporation, in a manner well known in the art 
Each of the flow rates of { TAIL ~ the reactant gases } is accurately controlled by { HEAD ~ conventional , commercially available mass flow controllers } , such as those from Tylan Corporation , in a manner well known in the art
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH