Characteristic cylindrical microphase-separated structures have been found for three ABC star-shaped terpolymers. The samples are composed of polystyrene (S), polyisoprene (I), and poly(2vinylpyridine) (P); their volume ratios of I:

The structure-preserving finite difference schemes for the one dimensional Cahn-Hilliard equation with dynamic boundary conditions are studied. A dynamic boundary condition is a sort of transmission condition that includes the time derivative, namely, it is itself a time evolution equation. The Cahn-Hilliard equation with dynamic boundary conditions is well-treated from various viewpoints. The standard type consists of a dynamic boundary condition for the order parameter, and the Neumann boundary condition for the chemical potential. Recently, Goldstein-Miranville-Schimperna proposed a new type of dynamic boundary condition for the Cahn-Hilliard equation. In this article, numerical schemes for the problem with these two kinds of dynamic boundary conditions are introduced. In addition, a mathematical result on the existence of a solution for the scheme with an error estimate is also obtained for the former boundary condition.

Several hierarchical nanophase-separated structures have been observed for a series of ABC star-shaped terpolymers by transmission electron microscopy (TEM) and electron computerized tomography (3D-TEM). The seven terpolymers synthesized are composed of polyisoprene (I), polystyrene (S), and poly(2-vinylpyridine) (P), their volume fraction ratios of I:S:P are 1:1:X, where X equals 0.2, 0.4, 0.7, 1.2, 1.9, 3.0, and 4.9, respectively, and additional four samples were prepared by blending each two parent terpolymers. From morphological observation by TEM and tomography, a terpolymer with X of 0.2 shows lamellar structure with spheres at the interface, those with X ranging from 0.4 to 1.9 show cylindrical structures with twodimensional tiling, while those with X of 3.0 and 4.9 show hierarchical cylinders-inlamella structure. Two the other terpolymer samples with X of 7.9 and 10 were produced by blending a P homopolymer with the terpolymer I 1.0 S 1.0 P 4.9 , and they both exhibited columnar piled disk cylinders in P matrix. From the comparison of the present results with the predictions by the Monte-Carlo simulation, it was confirmed that the observed nanophase-separated structures of the ISP star-shaped terpolymers are mostly in good agreement with the prediction.

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During space missions, such as the prospective Mars mission, crew labor time is a strictly limited resource. The diet for such a mission (based on crops grown in a bioregenerative life support system) will require astronauts to prepare their meals essentially from raw ingredients. Time spent on food processing and preparation is time lost for other purposes. Recipe design and diet planning for a space mission should therefore incorporate the time required to prepare the recipes as a critical factor. In this study, videotape analysis of an experienced chef was used to develop a database of recipe preparation time. The measurements were highly consistent among different measurement teams. Data analysis revealed a wide variation between the active times of different recipes, underscoring the need for optimization of diet planning. Potential uses of the database developed in this study are discussed and illustrated in this work.

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