Abstract:Based on the previous analysis of the surface coating of ancient Tibetan wall paintings at Labrang Monastery in Gansu, drying oils, such as tung oil and linseed oil, were employed to explore and reconstruct the procedure for making and the process for brushing traditional varnish. Also, a new varnish originating from traditional varnish recipes but combined with the advantages of modern oil-based paint is proposed. This new varnish is accessible and controllable in its structure and composition, and is compatible with the original historical surface coating. The structures of the traditional and “new-traditional” varnishes were analyzed using Fourier transform infrared (FTIR) spectrometry. The color, appearance, aesthetic effects and weatherability of the traditional and “new varnishes” were also evaluated and compared with modern synthetic varnishes, such as alkyd, fluorocarbon and novolac. The results indicate that the traditional and new-traditional varnishes have achieved the same chemical stability and weatherability as synthetic ones, while exhibiting better compatibility and aesthetic effects. These varnishes could be used as surface coating materials for Tibetan wall paintings in the future.

Abstract:The middle hall mural at Longju Temple is an example of classic Ming Dynasty temple murals in Sichuan. In order to ascertain the material and workmanship of the mural, the structural morphologies and material compositions of samples were analyzed using microscopy, laser particle analysis, X-ray diffraction (XRD),Raman spectrometry,and enzyme-linked immunosorbent assay (ELISA), etc. The results show that the structure the mural depends on is a mud wall with a bamboo skeleton. The mineral components of the plaster layer are mainly quartz and albite. The grain composition of the mural is powder in the majority and sand in the minority. In the Diangongban mural the coarse mud layer has a lower sand content and a higher powder content than the fine mud layer. The fibers in the coarse plaster layer are straw stalks and chaff and those in the fine plaster layer are cotton or fibrilia. Regarding colors, the red pigments are cinnabar and minium, the green pigments are atacamite and paratacamite, the white pigments are calcite and talcum, the black pigment is carbon black, the blue pigment is azurite, and the yellow pigment is goethite. The cementing material is animal glue or egg white. The mural is typical, in terms of carrier structure, plaster materials and color composition, compared with other murals of the same region and period. These research results could not only provide guidance for the following protection and restoration of the mural in the future, but also enrich the knowledge of ancient architectural murals in this area.

Abstract:In order to understand the pigment composition and production process of the murals in Xu Xianxiu’s tomb of the Northern Qi Dynasty, optical microscopy (OM), scanning electron microscopy (SEM), Raman spectrometry, X-ray diffraction (XRD) and other methods were used to analyze and study the pigments. The results show that the pigments are all inorganic mineral ones:red pigments include mainly iron red and cinnabar; yellow pigments are mainly lithargyrum; black pigments are mainly carbon black; gray pigments are mixtures of calcium carbonate and carbon black; green pigments are mixtures of sulfur; white pigments include calcium carbonate and arsenic-containing lead minerals and calcium carbonate is used for both a base layer and a face layer; in addition, the white ash layer of the tomb passage is mainly gypsum. These results provide new material for understanding the characteristics of mural pigments in the Northern Qi Dynasty.

Abstract:Because of the water-swelling properties of clay minerals and the poor cohesion between soil particles, surfaces of earthen sites are prone to deterioration such as spalling and powdering. Chemical consolidation, is an important protective measure against these kinds of deterioration, and although it has some achievements, its overall application is still limited due to its short aging period of materials and the difficulty of reprocessing. In view of this situation, this paper discusses a new protective measure—open microwave reinforcement. Microwave can change the microstructure of clay minerals through thermal and non-thermal effects, thereby enhancing their resistance to environmental effects. Moreover, with the advantages of accurate positioning and controllable energy, microwave can avoid the hazards to the soil and environment brought by chemical material volatilization, so it can safely and effectively consolidate the soil body and thus has a good effect. This paper also discusses the key technologies in the research and development of microwave equipment for strengthening earthen sites, including the determination of equipment parameters and the selection of frequency and auxiliary heat materials.

Abstract:A heterogeneous gravel bed is the main stratum for wall paintings of Mogao Grottoes, but it is still not clear how the heterogeneity of the stratum plays in the transport of water and salt in it. By three-dimensional high-density electrical resistivity tomographic monitoring, conducted in 1 m×1 m and 2 m×2 m regions at the surface of the west side wall of Cave 108, we found the spatial distributions of wall resistivity were heterogeneous in both regions. The spatial position, size and shape of the low-resistivity regions all changed with the time. This clearly indicates that there exists important water saturation and desaturation process (i.e. water redistribution process) in the heterogeneous gravel strata forming the painting wall. It is this repeated water saturation and desaturation process that drives the water to flow in the wall and causes the salt to accumulate in specific regions. The results of the study have a wider significance for fully understanding the water and salt transport mechanism in the walls of Mogao Grottoes, as well as reducing and preventing the salt-related damage to the wall paintings.

Abstract:Reinforcement of weathered sandstone relics is an important subject in the conservation of cultural relics. In the present study, we studied the materials and the laboratory techniques for the reinforcement of weathered sandstone relics using a kind of fresh sandstone as samples, the composition of which is the same as that of the seriously weathered stone artifacts at Yungang Grottoes. After chemical treatments of accelerated weathering, the sample has a weathering degree equal to the relics. We examined four materials and seven technical laboratory conditions for reinforcement. The penetration depth, color, salt tolerance, resistance to ultraviolet ageing and compressive strength performance of the samples before and after the reinforcement were measured. Our study demonstrates that ethyl silicate and its oligomers as well as hydroxyl siloxane administered using the decompression-dripping process have the greatest impact on reinforcement of the sandstone. The present study provides useful data for the reinforcement of sandstone cultural relics.

Abstract:An ancient Banjing-river ship was excavated in an offshore river channel in Taicang. In the early stages of conservation and restoration work, it is necessary to desalinate the object. In order to understand the salt content of the ship’s wood, the kind and content of salts in samples from different parts and of different tree species were analyzed. The results show that the soluble salts of C1- and SO2-₄ were in the samples. By ultrasonic-assisted heating and deionized water immersion for 20 days, the Cl- content could be controlled within 1 mg/L; after 100 days, the SO2-₄ content was within 1 mg/L. The results of this study may provide favorable conditions for further preservation.

Abstract:In our study, identification of timber species, based on their microscopic structures, was carried out on 29 samples from different hull units of the Southern Song Dynasty Huaguangjiao Ⅰ shipwreck, including the 1st to the 5th decks, the keel and columns. The results show that timber species were diverse but that the most frequently-used timbers are Cinnamomum Trew, Machilus Nees, Cunninghamia R.Br, Pinus Linn, Cupressus Linn and Drypetes Vahl, which are mainly from the central and southern China. Pinus Linn. is the main species. Most of these timbers are important traditional shipbuilding materials in China. In addition, the characteristics and sources of timbers used for different parts of the ship for different purposes were analyzed. Timber selection of Huaguangjiao Ⅰ shipwreck indicates that ancient craftsmen not only knew well the properties of different timbers, but could also reasonably select timbers for hull units with different functions.

Abstract:In our study, three kinds of metal threads used for a Qing Dynasty official’s costume were detected and analyzed using some modern techniques such as microscopic observation, scanning electron microscopy-energy dispersive spectrometry and infrared spectrometry. The structural characteristics and geometric dimensions of the metal threads, the alloy of the metal foil and the proportion of each element in the back layer were obtained. The results show that 1) the metal threads in the colored weft are silver-twined threads, and the core is silk yarn; 2) the other two kinds of metal threads with different sizes used in the Buzi are gold-twined threads. For the big ones, the core is cotton thread and for the fine ones, the core is silk yarn. The back lining materials used for the three kinds of metal threads are all paper, which is made from bamboo fiber and grass fiber filtered from the mixed bamboo and grass pulp. This study provides a more comprehensive and in-depth understanding of the current state of cultural relic conservation, and provides a reference and a basis for subsequent custody, protection and restoration work. It also presents scientific information for the study of gold application technology for textiles in the Qing Dynasty.

Abstract:A Zhongni-style Guqin named “Hu Xiao” (means tiger-roaring) (No. 6828) collected in Shaanxi History Museum, was a gift from a Guqin master, Pei Tiexia, to his disciple Li Fan, but the dynasty when it was made is unclear. Using lacquer film slicing and a variety of analytical methods—optical microscopy (OM), scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), X-ray diffraction (XRD) and Fourier transform infrared spectrometry (FTIR)—the residual lacquer film of “Hu Xiao” Guqin was analyzed. The lacquer ash contains quartz (SiO₂), lime (CaCO₃), gypsum (CaSO₄·2H₂O), clay , cinnabar (HgS) and white copper (Cu, Zn, Ni) detritus. Combined with related research results, the comprehensive analysis shows that the “Hu Xiao” Guqin was made in the Ming Dynasty, and its lacquer film layering, thickness and lacquer ash composition are closely related to the sound and the name of the Guqin.

Abstract:In order to identify the pigments and binding media of acrobat figures excavated from Pit K9901 of Emperor Qinshihuang’s Mausoleum, polarized light microscopy (PLM), Raman spectrometry and gas chromatography-mass spectrometry (GC-MS) were applied to study the two polychrome fragments. The results indicate that the binding media of the pigments is animal glue, the white pink pigment is a mixture of cinnabar and white lead, and the red pink pigment is a mixture of cinnabar and bone white. The study could provide important information about archaeological culture of Emperor Qinshihuang’s Mausoleum.

Abstract:Traditional folk paintings, used for the celebration of Chinese New Year, are a unique form of Chinese folk art. We introduce the history of red/blue pigments and dyes used for the printing of traditional folk paintings in this paper. In our study, we selected 15 kinds of representative red/blue pigments and dyes to test their Fourier transform infrared (FTIR) spectra, and then summarized the chemical structures and FTIR absorption features of these samples. Based on the standard spectra, we tested three traditional folk paintings printed in the late Qing Dynasty and early Republic of China using the attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectrometer. The results indicate that what were used on these paintings are synthetic pigments and dyes, including acid red G, methyl blue and Prussian blue. This work explores the application of FTIR technology in calligraphy and paintings, and provides a scientific basis for the nondestructive identification of pigments and dyes in traditional folk paintings.

Abstract:At present, there is a lack of specialized research on Jin-hua-yin silver ingots. In our study, in order to enrich the research in this regard, we analyzed nondestructively the elemental composition of six silver ingots with three Chinese characters “Jin Hua Yin” and six ordinary silver ingots of the Ming Dynasty, using X-ray fluorescence spectrometry (XRF). The results show that the silver content of the Jin-hua-yin silver ingots is higher and that the gold content is significantly higher than the ordinary silver ingots. The elements of iron, lead, copper and gold were measured on the surface of each side. The surface may contain corrosion products in a powdery form, and some of the Jin-hua-yin silver ingots have tightly-bound mercury elements on the surface. The silver contents of the ordinary ingots have individual differences, and their gold contents are all lower than those of the Jin-hua-yin silver ingots. In addition, the Jin-hua-yin silver ingots are similar in shape to the ordinary silver ingots of the same period. The analysis results provide a scientific basis for understanding the compositions and production methods of Jin-hua-yin silver ingots in the Ming Dynasty.

Abstract:The “Wen Chu” Fan of the Ming Dynasty and the “Yong Rong” Fan of the Qing Dynasty were suffering from diseases such as insect damage, losing parts, discoloration, powder loss, fan bone damage and breakage. Scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDX) and other scientific measures were used to conduct a comprehensive analysis and to help to solve some issues including the selection of supplementary papers, fixation of gold paper and filling of worm holes in the original folds of the fan surface. etc. Methods for fan surface cleaning, peeling, filling, color restoration and stroke connecting were also designed. During the fan bone restoration, ancient measures such as sticking, bonding and tenon joints were explored and then applied in order to recover the original appearance of the fans and to retain, as closely as possible, the aesthetics and practical values that ancient people had for folding fans. This is a new idea which combines traditional craftsmanship and modern technologies.

Abstract:In our study, we used Internet of Things networking technology to monitor the environment of Emperor Qinshihuang’s Mausoleum Site Museum. Compared with the off-line monitoring method, we believe that the Internet of Things technology provides better environmental monitoring for heritage preservation because of its smaller intervention in cultural relics, timely response, manpower-saving and intuitive grasp of the environmental status of different regions. Therefore, it is easy for us to contrast analysis and executive control. Although there are still some problems at this stage, by increasing the data storage capacity, expanding the battery capacity, smoothing out the network, and optimizing the sensor calibration measures, we could still enhance the effectiveness of environmental monitoring and improve environmental precontrol ability for cultural heritage.

Abstract:Based on neutron properties such as high-penetration and high-sensitivity to elements, neutron diffraction and imaging are applied to the in situ, nondestructive and bulk measurement to get information of quantitative composition and inner structure. In this paper, neutron diffraction and imaging are introduced in terms of instrumentation, its characteristics and its application in cultural heritage studies. This work reveals prospects for broad application in the field of culture heritage research, providing a reference for the nondestructive analysis of artefacts in China.