The secondary solidification phase of icosahedral (I-) phase in rolled MgZnY alloy is replaced with I + Ca 2 Mg 6 Zn 3 phases by addition of Ca. Addition of Ca in MgZnY alloy significantly accelerates dynamic and static recrystallization resulting in much fine grain size and more random texture. EBSD analysis indicates that the presence of Ca in the ¡-Mg solid solution matrix may play a role in weakening of basal texture rather than particle stimulation nucleation effect by the second solidification phases.

The effect of Sn (1, 3 and 5 mass%) addition on the precipitation behavior of AZ91 alloy has been investigated in the present study. The addition of Sn is effective in suppression of discontinuous precipitation as well as acceleration of continuous precipitation. The Mg 2 Sn particles at the grain boundary effectively reduce the nucleation sites for discontinuous β precipitates, and slow down the movement of the grain boundary. The addition of Sn remarkably enhances the aging response of AZ91. The hardness increases steeply with the start of the aging treatment, resulting in signi cantly higher peak hardness within shorter aging time. The addition of Sn enhances the aging response by solid solution hardening effect as well as by co-precipitation of Mg 17 Al 12 and Mg 2 Sn in the α-Mg matrix.

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Plasmalogen that contains choline was concentrated from bovine heart to 95% purity from an initial value of 45%, and ethanolamine-containing plasmalogen from bovine brain to 99% purity from initial 64% using phospholipase A 1 from Serratia sp. MK1 in a two-phase system. In the two-phase system, Ca2 + was not required and Tris/HCl buffer and butyl acetate were used as an aqueous phase and a solvent phase of the two-phase system, respectively.