摘要
本文通过对长白鱼鳞云杉和臭冷杉生材分别进行普通气干处理和酒精置换处理以及对其气干材进行水浸处理 ,研究了这 3种不同处理方法对木材气体渗透性的影响及其影响机理。研究结果表明 ,长白鱼鳞云杉边材、心材和臭冷杉心材的生材经普通气干处理后 ,其气体渗透性较低 ,分别约为 0 1 1 4、0 0 4 5和0 1 1 1darcy ;长白鱼鳞云杉边材、心材和臭冷杉心材的生材经酒精置换处理后 ,其气体渗透性分别约为1 1 71 3、0 0 74和 0 1 4 4darcy,比普通气干处理对照组试样的平均渗透性分别增加约 1 0 1 5倍、62 %和 3 0 % ,t检验表明 ,前者差异非常显著 ,但后两者差异不显著 ;已气干 1 8个月的长白鱼鳞云杉边材、心材和臭冷杉心材经水浸处理后 ,其平均气体渗透性较处理前分别增加约 85%、4 9%、65 5% ,t检验表明差异均显著。长白鱼鳞云杉生材边材经酒精置换处理后 ,其平均气体渗透性较普通气干处理试样的平均气体渗透性显著增加的主要原因 ,是经酒精置换干燥后其纹孔的闭塞率基本上保持同生材状态时一样低 ,绝大多数纹孔仍处于开放的中间位置的结果 ,其次一部分浸提物在置换过程中被浸提出也可能是个原因 ;
The effect of three different treatments on wood permeability and its mechanism were studied in the paper by air drying and ethanol exchange drying for green wood and by soaking in water then followed by ethanol exchange drying for air dried wood of yezo spruce (Picea jezoensis Var. komarovii) and fir (Abies nephrolep). The results showed that the specimen of green yezo spruce sapwood, heartwood and fir heartwood after air drying had a low permeability of 0.114, 0 045 and 0 111 darcy, respectively. The permeability of green yezo spruce sapwood, heartwood and fir heartwood after ethanol exchange drying was approximately 11 713, 0 074 and 0 144 darcy, respectively. Compared with the permeability of air dried specimen group, the average permeability was increased about 101 5 times, 62?% and 30?%, respectively. The t test showed that the difference for yezo spruce green sapwood was very significant while for yezo spruce and fir green heartwood it was not significant. The average permeability of yezo spruce sapwood and heartwood and fir heartwood samples which have been air dried for 18 months after the treatment of soaking in water for 2 weeks followed by ethanol exchange drying was increased approximately by 85?%, 49?%, 65 5?% over their controls before the treatment, respectively. The permeability difference of soaking treatment samples versus their controls was significant at the 5?% level by t test of paired comparative test. For yezo spruce green sapwood the significant increase of permeability after ethanol exchange drying compared with air drying was mainly due to the lower fraction of pit aspiration, and then the extraction of a small part of extractives from specimens were also probably responsible. For yezo spruce and fir green heartwood the increase of permeability after ethanol exchange drying compared with air drying was not significant because the ethanol exchange drying failed to prevent or decrease pits aspiration in yezo spruce and fir heartwood. For yezo spruce and fir air dried wood the increase of permeability as a result of soaking treatment was probably due to two aspects, that is, the deaspiration of some aspirated pits and the decrease of extractives in the specimen. However, for yezo spruce sapwood the former was probably the primary factor, whereas for yezo spruce and fir heartwood the latter was probably the major reason.
出处
《林业科学》
CAS
CSCD
北大核心
2000年第4期67-76,共10页
Scientia Silvae Sinicae
基金
国家"九五"攀登计划资助项目!( 95-专- 0 7)
关键词
木材渗透性
气干处理
溶剂置换处理
水浸处理
Wood permeability, Bordered pit, Pit aspiration, Pit deaspiration, Air drying, Solvent exchange drying, Soaking treatment
