| Project/Area Number |
11460081
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| Research Category |
Grant-in-Aid for Scientific Research (B).
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
林産学
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| Research Institution | KYOTO UNIVERSITY |
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Principal Investigator |
NORIMOTO Misato Kyoto Univ., Wood Res.Inst., Prof., 木質科学研究所, 教授 (20027163)
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| Co-Investigator(Kenkyū-buntansha) |
MOROOKA Toshirou Kyoto Univ., Wood Res.Inst., Assoc.Prof., 木質科学研究所, 助教授 (00192378)
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| Project Period (FY) |
1999 – 2000
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| Project Status |
Completed (Fiscal Year 2000)
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| Budget Amount *help |
¥7,500,000 (Direct Cost: ¥7,500,000)
Fiscal Year 2000: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 1999: ¥5,900,000 (Direct Cost: ¥5,900,000)
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| Keywords | Coniferous Wood / Early Wood / Fourier Transformation / Power Spectrum / Cell Model / Elastic Constant / Dielectric Constant / Anisotropy / 密度 / 比重 / 要素角 |
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| Research Abstract |
The elastic and dielectric constants of wood in the transverse direction depend strongly on cell structure such as cell shape and orientation. The aim of this study is to clarify the relationship between these properties and the cell structure. The transverse very thin sections of seven kinds of coniferous early woods were photographed under a light microscope and the micrographs were input into a computer through an image scanner. The power spectrum of the images was obtained by fast Fourier transformation and a representative cell model for each species was constructed. The elastic and dielectric constants for the models in the radial and tangential directions were calculated and the results were compared with experimental ones. Although the cell models for all species were hexagonal in shape, that of Tsuga heterophylla was nearly square, while those of Chamaecyparis obtuse and Pinus radiata were distinctly hexagonal. The equations to calculate elastic constants were shown by a function of the element angle, the cell thickness and the ratio of the axial length of tangential wall to that of the radial cell wall and was represented by the terms expressing contributions of the axial and bending deformations of the cell wall. The calculated values explained qualitatively the change of experimental values with density as well as the difference in the experimental values among species. The calculated values at the same density greatly differed depending on the element angle of the cell models. The anisotropy of elastic constant between radial and tangential directions depended on the difference in the bending contribution. On the other hand, the anisotropy of dielectric constant depended greatly on the difference in the arrangement of the cell wall and the cell lumen.
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