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To understand the structure of composite membranes prepared from polyacrylonitrile (PAN) and modified milk whey (MMW) or egg white (MEW), obtained by reacting with 2,4-tolylen diisocyanate, we have investigated the membrane potential, solute perme ability, and dyestuff adsorption. The membrane potential measurements confirm that at least some parts of modified protein components in composite membranes with high modified protein contents are incorporated by passing through the membranes. Solute permeability, equilibrium adsorption, and the adsorption rate of some dyestuffs through/on the composite membranes increase with increased modified protein content in the membrane. The properties of MMW/PAN and MEW/PAN are quite different because their characteristic structures are different: the shape of "island" MMW in "sea" PAN is elliptical, and that of "island" MEW is flat and oriented parallel to the membrane. Furthermore, equilibrium Methylene Blue (MB) adsorption on the composite mem branes indicates that there are some interactions between PAN and MMW up to a ratio of about 6.5 g (MMW)/100 g (PAN), and the interacted MMW parts have no affinity for MB.

Multicrystalline Mg2Si crystal with a diameter of 15 mm was grown via vertical Bridgman method. To clarify the growth mechanism of the multicrystalline structure, the grain growth behavior of the crystal was analyzed. This was carried out through segmenting grains by mean shift clustering using the light intensity profile obtained from multiple optical reflection images of the wafers and stacking the segmented images through the growth direction. Further crystal orientation measurement revealed that a grain with a higher surface energy competitively expanded to the lateral direction during crystal growth. We speculated that the growth behavior occurred because the supercooling was high enough to appear the difference of each grain’s growth rate. This idea was supported by crystal growth simulation to show a tendency for the crystallization rate to increase toward the latter half growth stage, which is consistent with the assumption for crystal grew with high supercooling.