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Chapter II Solution Growth….
Figure: 2.18 Plots of ln τ versus 1/lnS 2 for pure and DL-methionine doped KDP.
Figure (2.16),(2.17), (2.18) are plots of ln τ versus 1/lnS 2 , for pure KDP
and L-histidine doped KDP, threonine doped KDP and DL- methionine doped
KDP, respectively. However, the plots of figure (2.16-2.18) are not linear as
observed by Shanmugham et al [114]. However, the linear nature is observed
above 1.4 supersaturation, which is used for calculation of various nucleation
parameters. The similar nature was observed by Shanmugham et al [115].
The values of different nucleation parameters indicates that the induction
period, the interfacial tension, the energy of formation and radius of critical
nucleus decrease as the super-saturation increase. The similar results were
obtained by Shanmugham [114,115]. Moreover, the condensation of water
nuclei from vapor in presence of soluble salts like ammonium sulphate and
sodium chloride exhibited similar results [124].
Considering principles of homogeneous and heterogeneous nucleation
theories, the free energy of formation of a nucleus under heterogeneous
nucleation is less than homogeneous mediation [125]. Considering here the
addition of amino acids and their different solubility in water may be the
probable reason for the earlier precipitation of specks of doped amino acids to
further induce heterogeneous nucleation.
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