3.3. Effect of ultrasound irradiation intensity on the nucleation
From Fig. 5a, with the increasing ultrasound irradiation intensity, the nucleation temperature increased firstly, and then decreased with an increase in ultrasound irradiation duration. Meanwhile, for different ultrasound irradiation durations, the
variation of nucleation temperature can be categorized into two situations; irradiation at the intensities of 0.09 and 0.17 W cm-2 caused the nucleation to be decreasing linear with an increase in treatment durations, while the nucleation temperature increased firstly and then decreased under the intensities of 0.26 W cm-2 and 0.37 W cm-2 . Significant differences (p < 0.05) of nucleation temperature under different ultrasound durations with different ultrasound intensities were also observed from Fig. 5a.