Figure 2From: Selectively increasing of polyunsaturated (18:2) and monounsaturated (18:1) fatty acids in Jatropha curcas seed oil by crystallization using D-optimal design Response surface (a0 and contour plots (b) for the effect of the urea-to-FAs ratio ( X 1 , w/w) and crystallization temperature ( X 2 , °C) on the SFAs% ( Y 2 ) of NUCF. Back to article page