Properties of acid-washed activated carbon made from pruned apple branches with air-activation was investigated by comparison with the carbon from sugi (Cryptomeria japonica D.Don) prepared in the same way and acid-washed commercial activated carbon. The results disclosed that both its specific surface area and pore volume were largest among the three carbons. In particular, micropores were relatively larger than those of the other two carbons in diameter and mesopores with a diameter larger than 4nm were formed in the carbon. Besides, it was found that the water vapor adsorption amount was also greatest. This was supposed to be caused by the large mesopore volume because no functional groups effective on the adsorption were observed in these activated carbons.

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Because heavy floor-impact sounds generated in wood buildings might cause noise problems, they should be evaluated by using an index expressing the auditory sense from a resident's perspective. To find such an index, conventional and psychoacoustical evaluations of loudness, and also subjective evaluation of loudness based on the Magnitude Estimation Method were conducted for several heavy floor impact sounds generated in a wooden model floor. The floor featured flooring, sound insulating materials and shock absorbing materials used on a wood frame structure. Consequently, it was clarified that nonstationary loudness, which was one of the psychoacoustical indices, showed a higher correlation with the subjective evaluation than the maximum A-weighted sound pressure level, which was one of the common indices of loudness.

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We conducted pseudo-dynamic tests and earthquake response analysis on half scaled three-dimensional models of conventional wooden structures, by changing horizontal diaphragms stiffness, vertical walls stiffness and ground acceleration ratio in the perpendicular direction on the specimens. Displacement response of simulation agreed well with pseudo-dynamic tests. The lumped mass 3D-model is suitable for predicting earthquake response of this structure. We conducted also additional simulation on the specimens. The maximum displacement in the parallel direction of specimens was more affected by the eccentricity in the perpendicular direction than by floor stiffness. When the eccentricity ratio is under 0.3 in both directions of specimens, the ground acceleration ratios in the perpendicular direction and floor stiffness little effect on the maximum displacement response parallel to the specimens.

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For more efficient utilization of wood from plantations, Chinese white poplar (Populus tomentosa) was cut from Shandong Province, China. Changes of the position of the compressed layer, distribution of density and changes of hardness, as well as relations between surface density and surface hardness under the hygro-thermal control were studied. By means of controlling surface and inner MC of wood and pre-heating time before compression, the position of the compressed layer can be controlled and the number of compressed layers can be controlled to 1 or 2. The average density ranges from 0.79g/cm³ to 0.89g/cm³ of the compressed layers and from 0.61g/cm³ to 0.65g/cm³ in other parts, which shows a large difference with the compressed layers. The increase of density at compressed layers differs according to the position of the compressed layer. When it is at the surface, the density and hardness increased most compared with the controlled samples, showing a 78.1% and 127.6% increase, respectively, and the maximum density reached 1.00g/cm³. When the compressed layer is in the center, the density increased 57.1% compared to the controlled sample. The surface hardness increased exponentially with the increase of surface density.

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Various strength performances (bending, tensile, compression and shearing) of wooden frame- construction lumber (204, 206) sawn from sugi logs grown in southern Miyazaki were examined. Based on the result, stress grading using modulus of dynamic elasticity was conducted, and its necessity and effectiveness were compared with visual grading. With visual grading, select structural amounted to 80% in 204, and to 93.3% in 206. Also, the 5% lower limit of sugi exceeded the characteristic value of S-P-F second class, which mainly consist of dimension lumber, except for tensile strength of 206. Moreover, it was suggested that the stress grading method should be more effective than visual grading. It is thought that the structural calculation can be adapted to sugi by this scrutinized method equally to S-P-F. Therefore, if members which are adapted to the stresses of each location can be used effectively, it will be expected to increase the use of sugi significantly.

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