Biorefinery is a production system for fuels, energy, and chemicals from biomass in integrated chemical and energy industries, and it provides a new concept to change the petrochemical industry developed in 20th century. There is a growing demand to establish biorefinery to solve the problems of global warming and deficiency of fossil fuels because the biomass feedstock is produced by fixation of carbon dioxide by the photosynthesis of plants. In recent years, research and development for the production of bioethanol and value-added chemicals are progressively expanding, and the U.S. Department of Energy (DOE) selected 12 platform compounds as key intermediates for the biorefinery in USA. In this review, trends in the establishment of platforms for biorefinery and biological pretreatments for the conversion of lignocellulosics using white rot fungi are introduced.

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In this study, we manufactured six types of three-ply hybrid laminated materials reinforced by laminating aluminum alloy laminae on sugi wood (Japanese cedar), and investigated the influence of aluminum lamina thickness and lamina arrangement on the material's bending creep properties.
The initial deformation of aluminum was 0.11-0.13 times that of sugi wood and the initial deformation of hybrid laminated material decreased markedly with increasing thickness of aluminum lamina. The creep deformation of aluminum was 0.37 (1 mm thickness), 0.04 (2 mm thickness) and 0.07 (3 mm thickness) times that of sugi wood, and creep deformation of hybrid laminated material except for that with 1 mm thick laminae became considerably smaller than that of sugi wood. The extent of the decrease in initial deformation was greater in the H type whose aluminum laminae were laminated horizontally on the upper and lower sides of a radial section of sugi wood lamina than in the V type whose aluminum laminae were laminated vertically on both sides of a tangential section of sugi wood lamina, whereas for 2 or 3 mm thicknesses the extent of the decease in the creep deformation was greater in the V type.
The measured values of initial deformation and creep deformation of hybrid laminated material were greater than the values calculated from the measured values of aluminum and sugi wood. For the H type with 2 or 3 mm thick aluminum lamina, the ratios of measured to calculated value were considerably greater for creep deformation than for initial deformation. The ratios for both deformations were smaller for the V type than for the H type, and for hybrid laminated material with 2 or 3 mm thick aluminum, they were found to be considerably smaller in the V type than in the H type. This is considered to result from the effects of deformation in sugi wood and in glue lines caused by shear forces.

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Recently, acetoacetylated PVA (AAPVA) was introduced where part of the PVA side-chain was replaced with the reactive acetoacetyl group. A waterproof-type polyvinyl acetate emulsion (EPVAc) was synthesized by using AAPVA as the protective colloid of the emulsion adhesive on the basis of investigations of the characteristics of EPVAc. Its physical properties and wood bonding performance were investigated as summarized below.
1)After heat treatments of both 20 and 60°C, the physical properties of the adhesive did not show a large change. However, when heated at 120°C for 2 hours, AAPVA self-crosslinked and E" peak temperature became high, while the reduction of E' value was less at the high temperature region.
2)Hygroscopicity and water-solubility of EPVAc films were improved with AAPVA used as a protective colloid. Furthermore, it was proven that the plasticization of films by moisture absorption and the lowering of the storage modulus by heating were moderated for EPVAc films with AAPVA used as the protective colloid.
3)The water resistance of EPVAc using AAPVA was higher than EPVAc using normal PVA, and the wood bonding performance was rapidly improved by heating at 120°C.

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Indoor air quality of the wooden houses newly built according to the revised Building Standard Law was surveyed in Shizuoka and Aichi prefecture, 2004. Air concentrations of carbonyl compounds were measured in 20 living rooms and bedrooms of 10 houses of a natural type, furnished with natural materials, such as solid wood for floor and wall panels, and 18 rooms of 9 houses of a general type, furnished with artificial materials such as bonded wood materials for floors and polyvinyl covering for walls and ceilings. Average formaldehyde air concentration was 79μg/m³. The formaldehyde concentration of 70% of the rooms was above the guideline value in the 2000 survey. However, it was reduced to 20% in this survey. Formaldehyde concentration above the guideline value was measured in a few rooms just after completion of construction although it was apparent that the revision of the Building Standard Law did lead to a decrease of formaldehyde concentration. There was no difference in concentration between natural type and general type rooms. Average acetaldehyde concentration was 227μg/m³ and about 89% of the rooms were above the guideline value (48μg/m³) for air concentration. Acetaldehyde air concentration of general type houses and bedrooms was higher than that of natural type houses and living rooms. It was suggested that natural furnish materials lowered acetaldehyde air concentration.

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Our previous paper reported the results of carbonyl compounds air concentration in newly built wooden houses in 2004, consisting of 20 living rooms and bedrooms of 10 houses of natural type which is furnished with natural materials, such as solid wood floors and wall panels, and 18 rooms of 9 houses of general type which is furnished with artificial materials such as bonded wood materials for floor and polyvinyl covering for walls and ceilings, according to the revised Building Standard Law in Shizuoka and Aichi prefectures. In this paper we report the results of VOCs air concentration measurements. Toluene, styrene, xylene, p-dichlorobenzene, ethylbenzene and tetradecane were detected as guideline substances for indoor air quality of the Ministry of Health, Labour and Welfare of Japan. Toluene air concentration averaged 138μg/m³, and the concentration of about 11% of all rooms was over the guideline value (260μg/m³). Toluene concentration in general type rooms was higher than in natural type rooms. Styrene air concentration averaged 97μg/m³, and the concentration of about 11% of all rooms was over the guideline value (220μg/m³). Styrene concentration in general type rooms was higher than in natural type rooms. In addition, for general type houses, its concentration in bedrooms was higher than in living rooms. Air concentrations of the other four substances were low compared to the guideline values. The most abundant emission substances found in natural type houses were terpenoids. In addition, the concentration of substances other than terpenoids in natural type houses was lower than in general type houses. Furthermore, it was shown that for emission substances except terpenoids, low emission was found for the natural materials.

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The embedding strength of wood decayed by Fomitopsis palustris was investigated in this study. The embedding tests were conducted on decayed heartwood of sugi, karamatsu, Douglas-fir and spruce, and decayed sugi sapwood according to ASTM-D5764. The same tests were conducted on sound sugi, karamatsu, Douglas-fir and spruce at various moisture contents. Embedding strength of sound wood decreased as moisture content increased below the fiber saturation point (moisture content 28%), and became constant above the fiber saturation point independent of specimen and load direction. The strength above the fiber saturation point was 50% of the strength of air-dried specimens. The strength reduction by decay was remarkable in the spruce heartwood and the sugi sapwood. A strength reduction was not observed in other species for parallel to grain loading, but was the case only in sugi heartwood for perpendicular to grain loading. The strength reduction of decayed wood after ten weeks was greatest in sugi sapwood, followed, in order, by spruce heartwood, karamatsu heartwood, and Douglas-fir heartwood.

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