Chemical methods for the isolation and determination, and micro-analytical techniques of inclusions and precipitates in steels are reviewed. The several isolation and determination methods were recommended by the joint research societies (Iron and Steel Institute of Japan and Japan Society for the Promotion of Science) through above 30 years. Recently the quantitative isolation procedure of calcium aluminate (mCaO·nAl₂O₃), CaS and CaO in Ca-treated steels was carried out in a glovebox with an Ar atmosphere. Then the aqueous soluble inclusions (mCaO·nAl₂O₃ involved with high ratio of CaO) could be isolated quantitatively. On the other hand, the many micro-analytical techniques were applied to the characterization of inclusions and precipitates in several steels. For example, the distribution of Cu atomic cluster in Cu-added ultra-low carbon steels could be characterized by the atom-probe field-ion microscopy (AP-FIM) with 3-dimensional system.

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NIR spectra of plastic wastes with different color, thickness, and particle size of polymer materials were measured by using a portable NIR spectrometer to investigate their effects for the discrimination of plastic materials.
NIR and UV/vis spectra for 80 pieces of wastes plastic were measured and analyzed by principal component analysis (PCA) after standardization. The NIR spectra for different color samples had a little difference in the shape and the intensity. These differences could be brought by the difference of pigment additives and its particle size in each sample. And the results for PCA indicated that the color and form of the plastic samples were not affected to the discrimination of the plastics. It was also found that the types of waste plastic were discriminated by PCA with barcode NIR spectra effectively.

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A correlative method for determination of reaction rate constants in mixed solvents system previously proposed was applied for Diels-Alder reaction of isoprene-maleic anhydride. In this study, several binary mixed solvents such as hexane, toluene, ethyl acetate and monochlorobenzene with nitrobenzene were examined. By adjusting the model parameters for the excess activation energy, the relationship between rate constants and compositions of mixed solvents used were well explained. The excess activation energy was compared with the excess Gibbs energy predicted by an activity-coefficient equation.

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To determine the adequate condition for construction of the thin film constituted from lipid and color pigment, hybrid films of dimyristoyl-phosphatidylcoline (DMPC) and retinoic acid (retA) in several molecular ratios (9: 1, 4: 1, 1: 1, 1: 4, 1: 9) were prepared by means of Langmuir Blodgett method. The result was that in the ratio of retA and DMPC by 4: 1, the film showed relatively large absorption of light at the wavelength of 360nm. The result indicates the molecular ratio of retA and DMPC is important factor for construction of hybrid film structure in that retA functions efficiently as a color pigment.

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