246149.fig.004
Figure 4: Distribution curves of 1:1:1:1 Ni(II)-Zn(II)-valine-uracil system; (1) H2L1, (2) HL1, (3) HL2, (4) Ni(OH)+, (5) Ni(OH)2, (6) Zn(OH)+, (7) Zn(OH)2, (8) NiL1, (9) NiL2, (10) ZnL1, (11) ZnL2, (12) NiL1L2, (13) ZnL1L2 and (14) NiZnL1L2.