Relations Between Permeability and Structure of Wood

来源 :Forestry Studies in China | 被引量 : 0次 | 上传用户:wwangruir
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The permeability and the structure of heartwood and sapwood of the solvent-exchange dried and the air-dried greenwood of Chinese-fir (Cunninghamia lanceolata (Lamb.) Hook.) and masson pine (Pinus massoniana Lamb.) were measured in order to study the relations between the permeability and the structure. The results showed that the permeability of sapwood of both the air-dried and the solvent-exchange dried wood was higher than that of heartwood, and the permeability of the solvent-exchanged dried heartwood and sapwood was higher than that of the air-dried. A higher permeability of wood was attributed to, on the one hand, a bigger number of flow path per unit area of the wood perpendicular to the flow direction resulted from a bigger number of unaspirated pits per unit area and a bigger number of effective pit openings per membrane, and on the other hand, a smaller number of tracheid in series connection per unit length parallel to flow direction resulted from a longer tracheid length and an effective tra The permeability and the structure of heartwood and sapwood of the solvent-exchange dried and the air-dried greenwood of Chinese-fir (Cunninghamia lanceolata (Lamb.) Hook.) And masson pine (Pinus massoniana Lamb.) Were measured in order to study the relations between the permeability and the structure. The results showed that permeability of sapwood of both air-dried and the solvent-exchange dried wood was higher than that of heartwood, and the permeability of the solvent-infused dried heartwood and sapwood was A higher permeability of wood was attributed to, on the one hand, an greater number of flow path per unit area of ​​the wood perpendicular to the flow direction resulted from an enlarged number of unaspirated pits per unit area and an bigger number of effective pit openings per membrane, and on the other hand, a smaller number of tracheid in series connection per unit length parallel to flow direction resulted from a longer tracheid length an d an effective tra
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