采用升水容积置换法分别测量了I-72杨木材径向、弦向和纵向的气体渗透性,分析了含水率对杨木气体渗透性的影响。结果表明:同一含水率条件下,I-72杨木材径向气体渗透性稍大于弦向;在较高的含水率阶段,纵向气体渗透性略大于横向(径向、弦向),随着含水率降低,纵向气体渗透性与横向的差异急剧增大。而在各个纹理方向上不同部位的渗透性差异不明显。随含水率的降低渗透性有不同程度的提高,并且变异性较小。基于此,拟合出I-72杨木材的渗透性随含水率变化的关系模型。
Abstract
Gas permeability of wood is one of the most important physical properties and it reflects the difficulty level of fluid through wood. The permeability of wood can also reflects its drying rate and impregnating treatment effects during modification. The wood gas permeability of I-72 poplar were measured in radial, tangential, and longitudinal by the volume displacement method in this paper. Test results showed that the gas permeability in the radial section was a little bigger than that in the tangential section at same moisture content, and it was a little bigger in the longitudinal section than that in the radial section only at high moisture content.Furthermore, the difference of gas permeability in longitudinal and radial sections will be significantly enlarged along with the moisture content reduction. The permeability differences were not obvious at different position of poplar I-72 in three directions. The permeability increased differently with moisture content decreasing, on this basis, the mathematical equations of the permeability with moisture content changing were built.
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基金
收稿日期:2010-07-16修回日期:2010-10-26基金项目:江苏省高校自然科学基础研究项目(08KJB220001)作者简介:苗平(1963—),副教授,博士。Email: miaoping2000@126.com。引文格式:苗平,王晓敏,肖雪芹,等. 含水率对I-72杨木木材气体渗透性的影响[J]. 南京林业大学学报:自然科学版,2011,35(3):145-147.