泗水国出土泡桐材性研究

木质文物出土后环境发生了很大的变化,如不对其进行科学的保护处理就会发生快速的腐朽变化。在选择保护处理方法前对木材的材性进行科学的分析可以为保护方法的确定提供科学的依据。本工作从木材成分、含水率、干缩性、出土泡桐与新鲜泡桐干缩率比较、干燥过程中的电镜分析几个方面对泗水国汉墓出土的泡桐进行了材性研究。结果表明,泗阳汉墓出土的泡桐纤维素和半纤维素的含量比新鲜泡桐的含量下降很多,但木质素的相对含量却增加了,说明泗阳汉墓出土的泡桐在埋藏环境中可能更多地是受到褐腐菌的侵蚀。含水率的高低是反映木材腐蚀度一个重要指标,泗阳汉墓出土的泡桐平均含水率高达1211%,从弦向、径向、横切面的平均收缩率数值来看,出土的泗水国泡桐文物收缩变形很严重,从电子显微镜图片观察,细胞结构各向干缩特性与新鲜木材完全不同。由此可见,不能用常规木材的干缩特征和木材的变化规律来指导泗水国出土泡桐的研究和保护工作,在选择保护处理方法时要结合木材本身的现状选择适合的材料和工艺。

Studies of the wood property of the waterlogged Paulownia unearthed from the Han Dynasty tomb of Sishui Kingdom

Studies have been done on the wood property of the waterlogged Paulownia unearthed from the Han Dynasty Tomb of Sishui Kingdom in Siyang county,Jiangsu province.The chemical components of the Paulownia unearthed from Sishui Kingdom and fresh paulownia were analyzed.The results show that the content of the cellulose and semicellulose in the Paulownia unearthed from Siyang Han Dynasty tomb is much lower than that in the fresh paulownia,but the relative content of lignin is greater.These results indicate the Paulownia unearthed from the Han Dynasty tomb in Siyang may be much eroded by the brownrot fungus in the burial environment;The water content is an important index of the corrosion degree of wood,and the Paulownia unearthed from the Han Dynasty tomb in Siyang has a water content of up to 1211%.According to the average values of shrinkage in tangential direction,radial direction,and cross section,the very bad shrinkage and distortion has occurred in the unearthed Paulownia relics of Sishui Kingdom country,proving the wood cell wall has suffered serious destruction,so the wood shrank very badly.Studies were done on the dry shrinkage feature in radial,tangential and longitudinal directions and the variation feature of the wood cell wall during the dehydration for the Paulownia unearthed from the Han Dynasty tomb in Siyang.It can be observed in the electron microscope photograph that,the tissue structure of the unearthed Paulownia in Sishui Kingdom had undergone great damage,highly rotten,and a part of the photograph is difficult to identify for its internal structure.Its cell structure is completely different from that of a fresh wood in terms of each dry shrinkage feature.Therefore,dry shrinkage features and variation rules of a conventional wood can not be used to conduct the research and protection of the Paulownia unearthed in Sishui Kingdom.