For the catalytic process to produce drop-in fuel from biomass resource via furanic compounds, aldol condensation of furanic compounds with acetone plays an important role to control carbon number of the final product. In the present research work, base catalysis of anion exchange resin for aldol condensation of furfural with acetone was investigated. When three resins showing difference in the basic property were employed, the obtained data indicated that an increase of functional group consisting of quaternary ammonium salt in the resin enhanced the catalytic activity. Also, macro-reticular (MR) resin was more active in the test reaction than gelular one, which indicates that swelling of the resin matrix do not reach the sufficient level under the reacting condition of the aqueous aldol condensation. The produced aldol condensates were classified under two types: furanyl butenone (FB) and bis-furanyl pentadienone (BFP) having the carbon number of 8 and 13, respectively. MR type resin gave rise to high BFP selectivity compared with gelular one. But, the resin catalyst was deactivated with reusing it for the test reactions repeated.

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The present study investigated the influence of preparation conditions of hollow spheres of copper-cerium composite oxide on the morphology and catalytic activity for oxidation of carbon monoxide. The hollow spheres were obtained by a hydrothermal method using silica templates, and the homogeneity of the hollow spheres depended on the amount of urea used during preparation. X-ray diffraction studies indicated that the dispersion of CeO₂ in the copper-cerium composite oxide increased with the addition of urea during preparation. In addition, X-ray photoelectron spectroscopy studies indicated that the amount of surface copper also increased with the addition of urea. The hollow spheres prepared with urea showed a higher catalytic activity for oxidation of carbon monoxide than the sample prepared without urea due to the morphological homogeneity, dispersion of CeO₂, and surface composition of Cu species.

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Understanding of the amount of free cellulase or unrecoverable cellulase adsorbed on residue during enzymatic saccharification is important to recycle cellulase. As one example, cellulase adsorption behavior was tried to be explained when steam-exploded eucalyptus was saccharified with 51 FPU of cellulase cocktail per g-dry substrate for 2 to 16 hours. Cellulase adsorption onto the substrate was maximum at 2 h. The amount of adsorbed cellulase was gradually decreased, and then finally tended to be constant. The behavior is similar to that for enzymatic saccharification of the mixture of Avicel and lignin powder. It was estimated that cellulase was adsorbed onto both cellulose and lignin to their saturated adsorption capacity, and cellulose-adsorbed cellulase was liberated to liquor as cellulose is decomposed. The method to predict cellulase adsorption capacity of lignin in substrate by extrapolation to zero content of polysaccharide in the residue was proposed. In this study, about 30% of the loading cellulase seemed difficult to be recovered because of adsorption onto steamexploded lignin.

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The present article describes the implementation and effect of school activities that help children get close to photovoltaic (PV) systems in their elementary school, named the “PV-familiarizing activity.” This activity is composed of the following two actions. First, children observe and touch PV panels at their school. Next, for a certain period, they in turn clean PV panels and record the amount of electricity generated by the PV system at their school. The PV-familiarizing activity was implemented in three elementary schools in Yokohama city, Japan. To examine the effect of the PV-familiarizing activity on the school children, questionnaire and interview surveys were conducted to measure changes in emotional affinity to PV system of their school, environmental concern, electricity-saving behavior and so on. The survey results reveal that the PV-familiarizing activity can assist the school children in feeling attachment to the PV system of their school and seeing it as a symbol of their school. In addition, the school children may more strongly feel the importance of electricity, and increase environmental concern and electricity-saving behavior after the PV-familiarizing activity. It is conjectured that the PV-familiarizing activity helps the school children consider global issues of energy and environment as their own problems.

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