As will be discussed below, this ringed shaped portion establishes {HEAD ~ a reference region} 86 used in distinguishing between mobile ion drift and {TAIL ~ other effects} of temperature stress on contact potential measurements 
used in distinguishing between
As will be discussed below , this ringed shaped portion establishes { HEAD ~ a reference region } 86 used in distinguishing between mobile ion drift and { TAIL ~ other effects } of temperature stress on contact potential measurements
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL REL OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH