Monodispersed microspheres of vaterite CaCO 3 with a diameter adjusted to the range of 1−10 μm were produced through an amorphous intermediate with polystyrene sulfate. Whereas the microspheres were composed of nanocrystals with a diameter of ca. 20 nm covered with the organic polymer, the crystallographic direction of the entire sphere was evaluated to be macroscopically uniform from its single-crystalline features on polarization anisotropy and morphological evolution into a hexagonal shape with an additional growth process. A particular mosaic with a radially grown backbone structure consisting of oriented nanocrystals was suggested to exist in the microspheres from the electron diffraction patterns. The rigid mosaic framework was covered with a flexible organic component. Thus, various functional organic molecules including hydrophilic and hydrophobic dyes were successfully introduced into the microspheres due to the amphiphilic nature of the organic phase.

The microphase-separated structure of polyurethane bulk and thin films were investigated using atomic force microscopy (AFM). The polyurethane (PUs) were synthesized with poly(oxytetramethylene) glycol (PTMG), 4,4 0 -diphenylmethane diisocyanate (MDI) and 1,4-butanediol (BD) by a prepolymer method. The hard segment contents were 34 and 45 wt %. Polarized optical microscopy (POM) revealed that the 34 wt % PUE is homogeneous at a macroscopic level, while the 45 wt % one is macrophase-separated into two phases. One phase forms spherulites of ca. 2-5 mm in diameter. AFM observation for the 34 wt % PUE showed the microphase-separated structure, consisting of hard segment domains and a soft segment matrix. In contrast, for the 45 wt % PUE, a lot of the hard segment domains were observed in the spherulite region, indicating that spherulites include much amount of hard segment component, in contrast, outside of spherulite exhibited similar structure to that of 34 wt % one. For the PU bulk, the different microphase-separated structure in the inside and outside of spherulite was successfully observed for the first time. Also, the microphase-separated structure of PU films was investigated as a function of the film thickness. The PU films exhibited similar microphase-separated structure. For the thicker film ($200 nm), the interdomain spacing almost corresponded to bulk one. On the other hand, that for the film thickness below 7 nm dramatically decreased. This seems to be simply related to a decreasing space. We obtained the experimental data, which the phase-separated domain size of multiblock copolymer decreased with decreasing film thickness.KEY WORDS: Polyurethane / Microphase-separated Structure / Atomic Force Microscopy / Thin Film / A microphase-separated structure formed in polymers plays a quite important role for their properties, such as electric, adsorption, mechanical properties. To form the microphaseseparated structure in polymers, they need to possess block structures, which are chemically connected each other. It is well-known that the polyurethane elastomers (PUEs), which possess the multiblock structure, show the microphase-separated structure, 1-6 resulting in giving some unique properties, such as mechanical and adhesive properties [6][7][8][9][10][11][12][13][14][15][16] and biocompatibility.17

Magnesium ions are widely found in calcium-based biominerals as an accessory component. In this report, the influence of magnesium ions on the crystal growth of CaCO 3 was investigated on the basis of the nanostructure. The morphology of calcite grown in a supersaturated solution was drastically changed from a regular rhombohedron into a spherical architecture consisting of nanocrystalline mosaics in the presence of a large number of magnesium ions. While magnesium ions were substituted for ca. 6% of calcium ions in the crystal lattice at a maximum, an excess amount of magnesium produced an amorphous phase leading to the nanostructure with modulation of the crystal growth of calcite.

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"Demonstration on range imaging of 256 × 256 pixels and 30 frames per second using short wavelength infrared pulsed time-of-flight laser sensor with linear array receiver," Opt. Eng. Abstract. We demonstrated the range imaging with high resolution of 256 × 256 pixels and high frame rate of 30 frames per second (fps) using a short wavelength infrared pulsed time-of-flight laser sensor, which is suitable for long range imaging. We additionally demonstrated the long range imaging of more than 1 km and wide field of view imaging of 12 deg × 4 deg, 768 × 256 pixels, and 10 fps. For these demonstrations, we developed the linear array devices of the aluminum indium arsenide avalanche photodiode array and silicon germanium bipolar complementary metal oxide semiconductor read-out integrated circuit array. We also deployed the flattop beam illumination optics with the beam division and recombination method and realized efficient line shape illumination. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.