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Nakazono M.,Yamaguchi University | Yoshiura A.,Yamaguchi University | Mizunuma M.,Yamaguchi Prefectural Industrial Technology Institute | Koganei M.,Yamaguchi University
Journal of Environmental Engineering

Heat insulation specifications of the fitting which combined a Taiko-shoji with wooden pair glass sash are effective as the way of repairing a traditional wooden house with not only heat insulation performance but also the execution and design as well. In this paper, the insulation performance of Taiko-shoji was examined by indoor experiment, actual house measurement and numerical calculation. The results are as follows. As the result of indoor experiment, the heat resistance value of Taiko-shoji (air space=26mm) was at 1.3 times of single shoji and about 20% of the heat transfer coefficients decreased. As the result of measurement of improved actual house, the average heat resistance value of Taiko-shoji + pair glass was 0.64 m 3 K/W, pair glass only was 0.35 m 3 K/W. The overall heat transfer coefficient of Taiko-shoji + pair glass decreased to 27% of single glass by the numerical calculation. In case that the traditional house with single glass is repaired by Taiko-shoji + pair glass fitting, the validity of these specifications is shown by the simulations. Source

Imada K.,Yamaguchi University | Tanaka S.,Yamaguchi University | Ibaraki Y.,Yamaguchi University | Yoshimura K.,Yamaguchi Prefectural Industrial Technology Institute | Ito S.,Yamaguchi University
Letters in Applied Microbiology

There is very little information on the fungistatic or fungicidal effect of visible light. This study investigated the effect of 405-nm light, generated by a light-emitting diode array, on the economically important fungus Botrytis cinerea. The mycelial growth of B. cinerea was inhibited to the greatest extent by light at 405 and 415 nm and was negligibly inactivated at 450 nm, suggesting the presence of a photosensitizing compound that absorbs light mainly at wavelengths of 405-415 nm. Delta-aminolevulinic acid, a precursor of endogenous photosensitizer porphyrins, was used to determine the role of these porphyrins in 405-nm light-mediated photoinactivation of the fungus. Concentration-dependent inhibition of spore germination by delta-aminolevulinic acid and accumulation of singlet oxygen in the spores was observed when the spores were exposed to 405-nm light. These results suggest that the excitation of endogenous porphyrins and subsequent accumulation of singlet oxygen could partially explain the 405-nm light-mediated photoinactivation of B. cinerea. The development of symptoms in detached tomato leaves inoculated with B. cinerea spores was significantly reduced by irradiation with 405-nm light, indicating that 405-nm light has a potential use for controlling plant diseases caused by B. cinerea. © 2014 The Society for Applied Microbiology. Source

Kamimura A.,Yamaguchi University | Yamamoto S.,Yamaguchi University | Yamada K.,Yamaguchi University | Yamada K.,Yamaguchi Prefectural Industrial Technology Institute

Waste fiber-reinforced plastics (FRP) and unsaturated polyesters were readily depolymerized by subjecting them to a treatment with ionic liquids under heating conditions. The use of microwaves for heating effectively progressed depolymerization, whereas the conventional heating method was ineffective for this purpose. We isolated the monomeric material, phthalic anhydride, by direct distillation from the reaction pot under reduced pressure with yields of more than 90 %. We recovered the glass fibers in a pure form and achieved the effective removal of polystyrene, the linker unit of FRP. Ionic liquids were useful for several iterations of the reaction, and purification of the used ionic liquids was also possible. Thus, we developed a new use of ionic liquids for chemical recycling of waste plastics. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Yamada S.,Yamaguchi Prefectural Industrial Technology Institute | Tamura T.,Yamaguchi Prefectural Industrial Technology Institute | Mochizuki S.,Yamaguchi University
ICOPE 2015 - International Conference on Power Engineering

Effect of Reynolds number on the torque and power characteristics of a small straight-bladed vertical axis wind turbine has been investigated experimentally under various wind velocity. The maximum mean torque coefficient and the maximum mean power coefficient increase with increasing Reynolds number based on wind velocity and representative length of wind turbine. The tip speed ratio for the maximum mean torque coefficient is almost independent of Reynolds number. Otherwise, the tip speed ratio for the maximum power coefficient increased as increasing Reynolds number. When the curvature parameter and the solidity represented forms of the wind turbine are same, the wind turbine performance can be successfully explained by the simple analytical functions, namely, the mean torque and the mean power coefficients can be represented well by the logarithmic functions of Reynolds number and quadratic or cubic function of the tip speed ratio. The proposed approximate equations successfully predict the experimental data for the particularly higher tip speed ratio. Source

Kubuki S.,Tokyo Metroplitan University | Iwanuma J.,Tokyo Metroplitan University | Akiyama K.,Tokyo Metroplitan University | Mikuni A.,Yamaguchi Prefectural Industrial Technology Institute | Nishida T.,Kinki University
Hyperfine Interactions

In order to enhance the mechanical strength of Hagi Porcelain (Hagiyaki), one of the oldest and famous potteries in Japan, new preparation condition was examined. Tempered Hagi porcelain, denominated as 'Hagi Porcelain B', was prepared with the Porcelain clay originating from Daido district, Yamaguchi Prefecture, Japan. Structural change of 'Hagi Porcelain B' was investigated by means of 57Fe-Mössbauer spectroscopy, X-ray diffractometry (XRD) and three-point bending test. Mechanical strength of the 'original Hagi Porcelain B' was estimated to be 43.1 MPa by means of the three-point bending test, while much larger value of 104.5 MPa could be achieved when tempered by a chemical modification. Mössbauer spectrum of the 'original Hagi porcelain B' was composed of a paramagnetic doublet and a magnetic sextet due to Fe(III) of γ-Fe 2O 3(maghemite), while only one paramagnetic doublet due to to octahedral Fe(II)O 6 was observed for the 'tempered Hagi Porcelain B' with isomer shift and quadrupole splitting values of 1.13 and 2.15 mm s -1, respectively. It is considered that the absence of magnetic phase causes an increase of the mechanical strength because the maghemite phase has a defect spinel structure. These results indicate that mechanical strength of the 'Hagi porcelain B' could be enhanced by controlling the sintering condition. © 2012 Springer Science+Business Media B.V. Source

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