摘要
甘肃独特的地理、气候环境,一般考古出土木器都具有糟朽木器的典型特征,通常器物因木质结构与形态的脆弱性易受外部因素侵蚀而受损,而其腐蚀状况或发生腐变往往与其所处的埋藏环境、发掘现场和博物馆馆藏环境有关。鉴于目前甘肃糟朽木器的保存状况,通过甘肃糟朽木器埋藏环境、馆藏环境及影响因素调查,馆藏环境腐蚀作用与机理的科学剖析,全面、客观和准确地揭示了藏品腐蚀受损根源及原因。环境腐蚀作用的机理如下:1)可见光、紫外线腐蚀机理是,在光辐射的作用下,纤维素发生初始光化学反应造成链断裂,并伴随产生多种化合物。2)纤维素在常温下是很稳定的,但随着温度的升高,其强度相应降低,在高温光照和氧存在的情况下,会发生氧化反应;在水分、可见光、氧气、酶及酸碱等因素同时存在情况下,温度偏高则对糟朽木器材质腐蚀起着加速作用。3)可溶盐对糟朽木器材质的腐蚀作用是通过自身的潮解和结晶过程来完成的。4)害虫及霉菌、微生物对木质文物的腐蚀作用,主要是通过分泌各种生物酶来分解木质成分中有机质实现的。5)当空气中的湿度达到70%时,灰尘及粉尘会发生潮解,当沉降在糟朽木器表面时,会引起木质纤维素腐蚀和降解。
Archaeological wooden objects excavated from Gansu are generally rotten and show typical corrosive characteristics due to the unique geographic environment and climate. Usually, wood objects are unstable to the outside environmental elements due to their wooden character and structure. The burial site, excavation process and museum environment all affect the decay of wood. Based on the current state of preservation of rotted wood objects from Gansu, the burial site conditions, museum environment and the influencing factors of exterior environment were investigated ; the process and effect of environmental factors were analyzed ; and the process and cause for deterioration were revealed. The mechanism of environmental corrosion includes the following factors. 1 ） Deterioration due to visible light and ultraviolet radiation, namely photochemical reaction in cellulose, leading to the breakage of cellulose chains and the production of several new compounds. 2） Decay of cellulose, which is stable at room temperature, but becomes unstable with and increase in temperature, being oxidized in the presence of both high temperature illumination and oxygen. The presence of water, visible light, oxygen, enzymes, acidic or alkaline environment and high temperature accelerates the deterioration of rotten wood. 3 ） Soluble salts deteriorate the rotten wood by deliquescence and crystallization. 4） Mold, microbes and other pests harm wooden objects by secreting enzymes that decompose organic compounds in wood. 5 ） When the relative humidity was above 70%, the dust in the air deliquesces. When the dust settled on the surface of rotten wood, it can lead to the deterioration and decomposition of cellulose.
出处
《文物保护与考古科学》
2009年第4期67-73,共7页
Sciences of Conservation and Archaeology
基金
2005年度甘肃省文物局文物博物馆科研项目资助(200507)
关键词
甘肃
糟朽木器
腐蚀作用
机理
Gansu
Rotten wood
Deterioration process
Mechanism
作者简介
作者简介：陈庚龄（1971-），男，甘肃天水人，1996年毕业于华北工学院，现于甘肃省博物馆从事文物保护，副研究员，兰州市西津西路3号，邮编：730050，E—mail：690161262@qq．com
