Asheet of steel 3-mm thick has nitrogen atomospheres on both sides at 900 c and is permitted to achieve a steady-state di usion condition. the di usion coecient for nitrogen in steel at this temperature is 1: 85 m2=s, and the di usion ux is found to be 1: 0 kg=m2s. also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 2 kg=m3. how far into the sheet from this high-pressure side will the concentration be 0.5 kg/m3? assume a linear concentration profile.