长白鱼鳞云杉木材纹孔塞不同位置对渗透性的影响

Effect of Different Positions of Bordered Pit Torus in Yezo Spruce on Its Permeability

通过对长白鱼鳞云杉 (Piceajezoensisvar.komarovii(V .Vassil.)ChengetL .K .Fu)生材分别进行气干处理和酒精置换处理以及对其气干材进行水浸后再用酒精置换处理 ,研究了此 3种处理方法形成不同的纹孔塞位置对木材渗透性的影响。结果表明 ,边材和心材的生材经气干处理后 ,其中边材的早材和晚材纹孔闭塞率增加至 99%和81% ,而心材因为其纹孔塞在立木时就已发生偏移 ,其早材和晚材纹孔闭塞率亦高 ,分别为 97%和 86 % ;由于其绝大多数纹孔塞偏离中央位置 ,气体渗透性较低 ,边材和心材分别为 0 .114和 0 .0 45darcy。生材经酒精置换处理后 ,使绝大多数纹孔塞保持中央位置 ,其中边材的早材和晚材纹孔闭塞率低 ,分别为 8%和 17% ,而心材因为绝大部分纹孔在立木时即已为关闭状态 ,酒精置换处理以降低其闭塞率无效 ,故其纹孔闭塞率高 ,分别为 97%和 86 % ;此种状态下边材和心材的气体渗透性分别为 11.713和 0 .0 74darcy ,比普通气干处理状态下的渗透性分别增加 10 1.5倍和 6 2 .0 % ,t检验表明 ,前者差异非常显著 ,但后者差异不显著。气干材经水浸处理后再用酒精置换处理 ,其边材的早材和晚材纹孔闭塞率分别降低了 18%和 2 2 % ,心材分别降低了 0和 17% ;其气体渗透性分别为 0 .439和 0 .0 6 0darcy 。

The green wood of yezo species ( Picea jezoensis var. komarovii (V. Vassil.) Cheng et L. K. Fu) was treated with air drying and ethanol exchange drying and by soaking the air-dried wood in water followed by ethanol change drying. The results showed that the proportion of aspirated pits in the respective earlywood and latewood of the air-dried sapwood was increased to 99% and 81%, while that of heartwood was also as high as 97% and 86% because most of the bordered pits were aspirated at its green state. The permeability of air-dried sapwood and heartwood was as low as 0.114 and 0.045 darcy respectively. The proportion of aspirated pits in the earlywood and latewood of sapwood after ethanol exchange drying was very low (8% and 17% respectively), whereas that of heartwood was very high (97% and 86% respectively) since most of the pits in it were aspirated at its green state, so the ethanol exchange drying failed to prevent pit aspiration. The permeability of sapwood and heartwood after ethanol exchange drying was 11.713 and 0.074 darcy respectively, which was increased 101.5 times and 62.0% over the permeability at air-dried state. t test showed that the difference of permeability of ethanol exchange drying versus air drying for sapwood was very significant at the level of 0.1%, but was not significant for heartwood. The proportion of aspirated pits in earlywood and latewood of air-dried sapwood and heartwood after soaking in water followed by ethanol exchange drying was decreased by 18% and 22%, and 0 and 17%, respectively, while the permeability of sapwood and heartwood was 0.439 and 0.060 darcy respectively, which was increased by 85% and 49% respectively. The permeability difference of soaking sapwood and heartwood versus their controls was very significant at the 0.1% level by t test.