Essentially, therefore, {HEAD ~ a thin water film} exists in the pores of {TAIL ~ the sensor element}, and the reaction occurs in this aqueous solution 
Essentially , therefore , { HEAD ~ a thin water film } exists in the pores of { TAIL ~ the sensor element } , and the reaction occurs in this aqueous solution
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH