The OES analyzes light captured from {TAIL ~ a spark emission stand} through which {HEAD ~ the fluid sample} is flowed 
The OES analyzes light captured from { TAIL ~ a spark emission stand } through which { HEAD ~ the fluid sample } is flowed
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL REL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL