highly significantp -value < 0.01
It can be shown that A, A 2 , B 2 , and C 2 had a highly significant effect on the extraction yield ( p -value < 0.01).
It can be shown that A, A 2 , B 2 , and C 2 had a highly significant effect on the extraction yield ( p -value < 0.01).
As the extraction duration increased, the extraction yield first exhibited an increasing trend before declining, as illustrated in Figure 2 b.