{HEAD ~ Each particle} is covered with {TAIL ~ an insulative oxide film} which contains 0.3 to 0.8% of oxygen by weight based on the particle 
{ HEAD ~ Each particle } is covered with { TAIL ~ an insulative oxide film } which contains 0.3 to 0.8 % of oxygen by weight based on the particle
HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH