{TAIL ~ Magnetite particles} 1, wherein the specific surface area of the magnetite particles by {HEAD ~ the BET method} is given by the equation 
{ TAIL ~ Magnetite particles } 1 , wherein the specific surface area of the magnetite particles by { HEAD ~ the BET method } is given by the equation
TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH