Furthermore, the present protective overcoats have high density, generally being {HEAD ~ over about 2.5 grams} per {TAIL ~ cubic centimeter}, and are also very chemically inert 
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Furthermore , the present protective overcoats have high density , generally being { HEAD ~ over about 2.5 grams } per { TAIL ~ cubic centimeter } , and are also very chemically inert
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH