The surface area of {TAIL ~ contact} between {HEAD ~ the first and the second layers} can define a frame about the perimeter of the reservoir 
The surface area of { TAIL ~ contact } between { HEAD ~ the first and the second layers } can define a frame about the perimeter of the reservoir
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH