extremely significantp < 0.001
As shown in Table 4 , the p -value of this experimental model is much less than 0.0001, indicating that this model has a high degree of significance (significant at p < 0.05, extremely significant at p < 0.001), and the lack of fit p = 0.1225 > 0.05 indicates that the experimental processes are nearly not affected by other unknown factors.