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