Sample NC1,NC2 and NC3 were prepared with different single duration time and cumulative time, 10 min and 60 h (NC1), 30 min and 60 h (NC2), 60 h and 180 h (NC3) respectively.
Sample NC1,NC2 and NC3 were prepared with different single durationtime and cumulative time, 10 min and 60 h (NC1), 30 min and 60 h (NC2), 60 h and 180 h (NC3) respectively.