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