871824.fig.004a
(a)
871824.fig.004b
(b)
871824.fig.004c
(c)
871824.fig.004d
(d)
Figure 4: Typical PL spectra of the polycrystalline diamonds from the Mengyin kimberlite pipes ((a) and (b) EFPCDs; (c) and (d) ARPCDs).