3.4. Effect of high-pressure processing and annealing on the formation
of RS3
Fig. 3 shows the effect of high-pressure treatments at 60 C on
the yield of RS3 in DAS-20. It is clear that the RS3 levels in DAS-
20 can significantly improve by combining pressurising at
400 MPa and annealing for various times (Fig. 3A); although at a
treatment time of 24 h, the increase in RS3 is not significantly different
(P > 0.05) between 400 MPa HPT-DAS and the control-annealed
sample. During the first 15 min, the RS3 formation in the
combined treatment at 400 MPa surprisingly accelerated with a
25.7% increase (from 28.7 ± 0.5% to 36.1 ± 0.5% RS), whereas the
control-annealed sample only had a 9.7% increase of RS (from
28.7 ± 0.5% to 31.5 ± 1.1% RS). These results clearly indicate that