莫高窟壁画疱疹病害的微观形貌和成分研究

目的研究壁画疱疹盐分或元素的分布规律,为病害治理提供依据。方法使用扫描电子显微镜(SEM)、场发射扫描电子显微镜(FESEM)、X射线能谱(EDS)、X射线衍射(XRD)对疱疹表面的微观形貌、结构及成分进行分析。结果 SEM研究结果表明,疱疹表面被粘土质包裹,其核心部分为无机结晶盐,从部分疱疹剖面可观测到立方体或者近立方体形态的无机盐晶体。FESEM及EDS分析结果显示,大部分疱疹盐结晶的主要成分以Na、Cl元素为主,少部分疱疹中含有Mg、Ca、S等元素。另外,疱疹中Na和Cl以及S和Ca元素具有良好的比例对应关系。结论莫高窟壁画疱疹中的无机盐主要由易溶盐Na Cl构成,少量疱疹还含有CaCl_2、MgSO_4、CaSO_4等可溶盐或中溶盐。

Micro-morphology and Composition of Mural Herpes in Mogao Grottoes

The work aims to study the distribution law of salt or elements in mural herpes so as to provide basis for mural salts damage treatment. The morphology, structure, internal elements and composition of the herpes were investigated by virtue of scanning electron microscopy (SEM), field emission scanning electron microscopy (FESEM), X-ray energy spectrometer (EDS) and X-ray diffraction (XRD). The SEM and FESEM clearly showed that the herpes surfaces were covered by clay with a major composition of inorganic crystals of salt in the core herpes. Furthermore, cubic or cube-like salt crystals could be observed on cross-sections of the herpes. According to the results of FESEM and EDS analysis, the Na and Cl elements were main components of salt crystals in the majority of herpes, and Ca, S, Mg and other elements could also be detected in some herpes. More specifically, some elements, such as Na and Cl, Ca and S, exhibited good proportionality. On the basis of above results, it can be concluded that the inorganic salts in mural herpes are mainly composed of soluble salt NaCl, and a small number of herpes contains soluble salt or sparingly soluble salt such as CaCl2, CaSO4, MgSO4.