Synthesis of geranyl acetate by lipase entrap-immobilized in cellulose acetate-TiO2 gel fiber

Lipase from Candida antarctica was entrap-immobilized in cellulose acetate-TiO₂ gel fiber (fiber-immobilized lipase) by the sol-gel method. Syntheses of geranyl acetate and citronellyl acetate catalyzed by the fiber-immobilized lipase were studied in heptane solution. Conversions reached 85% for geranyl acetate after 100 h, and 75% for citronellyl acetate after 80 h, and these values were almost identical to those for syntheses catalyzed by nonimmobilized lipase, although the reaction rate was decreased by immobilization. Compared to those of the non-immobilized lipase and commercially available immobilized lipase (Novozyme 435), the activity of the fiber-immobilized lipase was not particularly affected by changes in reaction conditions, such as bulk water content or substrate concentration. The fiber-immobilized lipase retained a high level of activity after six repeated uses, and almost no enzyme leakage from fiber was observed. However, the reactivity of the fiber-immobilized lipase was depressed at higher temperature, presumably due to dehydration by thermal contraction of the gel fiber.     

Supramolecular Architectures of Nucleic Acid/Peptide Hybrids

Supramolecular architectures that are built artificially from biomolecules, such as nucleic acids or peptides, with structural hierarchical orders ranging from the molecular to nano-scales have attracted increased attention in molecular science research fields. The engineering of nanostructures with such biomolecule-based supramolecular architectures could offer an opportunity for the development of biocompatible supramolecular (nano)materials. In this review, we highlighted a variety of supramolecular architectures that were assembled from both nucleic acids and peptides through the non-covalent interactions between them or the covalently conjugated molecular hybrids between them.     

Phase separation behavior and morphology development of phenolic resin/PMMA/hexamethylenetetrarnine blends

Summary In order to obtain materials with nanopores which will be applicable for many fields, the structures of the cured blends of phenolic resin (PhN), poly(methyl methacrylate) (PMMA) and curing agent were studied. After PMMA was extracted from cured blends, the structures of cured phenolic resins were observed with SEM. As a results, it was found that nanosized continuous pore structures were formed in extremely wide composition region if curing temperature was high.     

Chromatic adaptation in a 2D photograph demonstrated by a D‐up viewer

It is said that we cannot have color constancy in a photograph. The concept of recognized visual space of illumination (RVSI) asserts that chromatic adaptation occurs when one perceives the illumination that is filling a space and not the objects in the space. It predicts then that if one perceives a 3D scene in a photograph, then color constancy will occur in the photograph. In this work, a dimension‐up (D‐up) viewer was developed to perceive a 3D scene on a 2D photograph, and the effect of chromatic adaptation was measured by the color appearance of a gray patch placed at the center of the photograph. Subjects saw the patch as a vivid color when they saw a photograph that had been taken under colored illumination, which is a normal experience in a real space observation. When the color appearance was measured by the elementary color naming method, the amount of chromaticness of the patch in percentage and the apparent hue were very similar to those observed in the 2‐room technique, thus confirming the prediction by the RVSI theory.     

Influence of Cu metal on the domain structure and carrier mobility in single-layer graphene

We demonstrate that domain structure of single-layer graphene grown by ambient pressure chemical vapor deposition is strongly dependent on the crystallinity of the Cu catalyst. Low energy electron microscopy analysis reveals that graphene grown using a Cu foil gives small and mis-oriented graphene domains with a number of domain boundaries. On the other hand, no apparent domain boundaries are observed in graphene grown over a heteroepitaxial Cu(111) film deposited on sapphire due to unified orientation of graphene hexagons. The difference in the domain structures is correlated with the difference in the crystal plane and grain structure of the Cu metal. The graphene film grown on the heteroepitaxial Cu film exhibits much higher carrier mobility than that grown on the Cu foil.     

Relationship between degree of polymerization and optical and thermal properties of fluorene in polycarbonate polymers

The influences of average degree of polymerization (D_p) and terminal group on thermal and optical properties of high refractive indexed transparent polymers were investigated. In this study, 9,9‐bis[4–(2‐hydroxyethoxy) phenyl] fluorene (BPEF) homo polymer was selected because it has been used as a representative monomer in high refractive index polymers as well as its unique property. BPEF has stable amorphous phase and reacts like a polymer. Its unique reaction allows continuous investigation from monomer to polymer. For hydroxyl‐terminated polymer, the refractive index (n_d) decreased with increasing D_p. On the other hand, for a phenolic‐terminated group, n_d increased with increasing D_p, and both converged to same value in high D_p region. As for glass transition temperatures (T_g), both terminal group series were increased as D_p increased. Though T_g of hydroxyl‐terminated polymer was higher than that of phenolic‐terminated polymer in the low D_p region, both converged to the same value and the inverse number of T_g had linear correlation against the weight percentage of carbonyl groups (CO), which was calculated by D_p. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45042.     

A new refining process for iron oxide using iron ore and its application to hard ferrites

Kawasaki Steel Corporation and Kawatetsu Mining Co., Ltd. have developed a new refining process to extract iron oxide from iron ore to meet the increase in demand for iron oxide for high- grade hard ferrites. This article discusses the quality of iron oxides and the characteristics of the hard ferrite magnets produced from them.     

Mechano-catalytic overall water splitting on some mixed oxides

Simple transition metal oxides such as NiO, Co₃O₄, Fe₃O₄ and Cu₂O were found to catalytically decompose water into H₂ and O₂ by mechanical energy. The reaction is regarded as “mechano-catalytic” overall water splitting” and is a quite novel catalytic reaction. In this paper, some general aspects on the mechano-catalytic overall water splitting are reviewed on simple oxides. In addition, recent results on the mechano-catalytic activity of a groups of mixed oxides, wolramite-type oxides with a formula of ABO₄ (A=Fe, Co, Ni and Cu, etc., B=W, Mo), are shown. AWO₄ (A=Fe, Co, Ni and Cu) decomposed water into H₂ and O₂ under the supply of mechanical energy, indicating that mechano-catalytic overall water splitting proceeded on wolframite-type compounds containing 3d-transition metals. AMoO₄ (A=Fe, Co, Ni) also decomposed water into H₂ and O₂ under supply of mechanical energy. The reaction properties on wolframite-type oxides are discussed.     

Effect of medium-chain fatty acid positional distribution in dietary triacylglycerol on lymphatic lipid transport and chylomicron composition in rats

The present study was carried out to examine if the positional distribution of medium-chain fatty acid (MCF) in dietary synthetic fat influences lymphatic transport of dietary fat and the chemical composition of chylomicrons in rats with permanent cannulation of thoracic duct. Four types of synthetic triacylglycerol were prepared: (i) sn-1(3) MCF-sn 2 linoleic acid, (ii) interesterified sn-1(3) MCF-sn 2 linoleic acid, (iii) sn-2 MCF-sn-1(3) linoleic acid, and (iv) interesterified sn-2 MCF-sn-1(3) linoleic acid. A purified diet composed of equal amounts of the synthetic fat and cocoa butter was given to rats with permanent lymph duct cannulation. The positional distribution of MCF in the dietary fat had no significant effect on the lymph flow, triacylglycerol output, phospholipid output, lipid composition of chylomicrons, or the particle size. The positional distribution of MCF in the synthetic triacylglycerol was maintained in the chylomicron triacylglycerol. These results showed that MCF in the dietary triacylglycerol is transported into lymphatics and the positional distribution is well preserved in chylomicron triacylglycerol.