Abstract:Several painted clay sculptures in Fengguo Temple in Yixian County, Liaoning Province, showed the severe problem of leaning. A preliminary investigation was conducted, and it was concluded that the inclination was caused by the decay of the wooden skeletons inside the sculptures. With the aim of defining the reason for deterioration of the wooden skeletons, collection of decayed samples in an on-site investigation was carried out, in order to determine the species of the wood samples and the microbes and to identify dead insect corpses. The results show that:1) the two wood samples were hardwood pine (Pinus sp.) and poplar (Populus sp.); 2) there was no wood-decaying fungi, only one strain of the mold, Aspergillus sp. was isolated, and Ascomycota fungi were the main species, according to fungal diversity analysis; 3) insects were identified as Coleoptera beetles, belonging to 4 families, namely Curculionidae, Anobiidae, Dermestidae and Tenebrionidae. Considering that Liaoning is located in the moderate decay hazard zone (D2) in the wood decay hazards map, the primary influence of the deterioration is mainly due to beetles. It is speculated that there was no pretreatment against the larvae and eggs of beetles, or that the pretreatment was not thorough, and later the eggs were hatched and then damaged skeleton wood, finally causing the sculptures to incline. In addition, further investigations show that some columns, beams and other wooden structures in the main hall also had emergence holes with a diameter of about 3 mm, indicating that there is some connection between the sculptures and the building when the biological hazard exists. This research reveals the impact of biodeterioration on the painted clay sculptures and the importance of preventive treatments for wooden skeletons inside the sculptures, and also provides ideas for the preventive conservation and conservation protocols to be designed for clay sculptures in Fengguo Temple and other wooden heritage structures.

Abstract:Near-surface weathering is a crucial problem threatening the preservation of rock-hewn cave temples. Erosion pattern evaluation and risk assessment through property variation of the weathered surface is a vital point that needs to be addressed for preventive conservation. In this study, we used portable non-destructive testing instruments (ProceqEquotip 550 Leeb hardness tester, FLIR T660 infrared thermal camera) to measure surface hardness and to monitor the surface temperature of 8 studied surfaces on the facade of the North Grotto Temple in Qingyang, Gansu Province. Based on the in-situ measurement, we studied the thermal response and property changes of the typical weathering patterns. The study results show that different weathering patterns could directionally affect the magnitude of surface hardness and the range of temperature fluctuation to some extent. The diurnal temperature of the crust surface fluctuated within a minor degree, and the surface hardness was broadly dispersed at a high range of value. The diurnal temperature fluctuations of the powdering surface and salt efflorescence surface were relatively gentle and flattened, and their surface hardness values were centralized at a low level. The diurnal temperature fluctuation of the groove-like erosion (differential weathering) surface was slightly greater than that of surfaces with powdering and salt efflorescence, and the surface hardness was centralized at a higher level. Surfaces covered with microorganisms had the most extensive range of diurnal temperature fluctuation, and scattered surface hardness values were distributed at a low level. Given the above evidence, the relationship between weathering patterns and properties can not only help with the distinguishing of distribution and developmental trends of weathering patterns in daily monitoring but also has an indicative effect on the risk warning of rock-hewn cave temples.

Abstract:The phenomenon of whitening is frequently observed in ancient jade artifacts unearthed in China, with a particularly high prevalence at the Sanxingdui site. In this study, X-ray diffraction (XRD), laser confocal micro-Raman spectrometry (Raman), Fourier transform infrared (FTIR) spectrometry, and simultaneous thermal analysis were used to analyze whitened jades excavated from the Sanxingdui site. The XRD results indicate that the primary phases of the whitened jades were calcite and diopside—the latter can be generated through the transformation from tremolite with heat. The Raman result indicates the presence of a pronounced hump-shaped fluorescence background for the jades. This type of fluorescence is more prevalent in carbonate minerals with elevated levels of sedimentary organic matter. The formation of tremolite jade is a consequence of high-temperature hydrothermal fluid flowing through magnesium carbonate rock. During the diagenetic transition, the dispersed organic matter in magnesium carbonate rock is partially retained in the tremolite. Carbonatite minerals and tremolite jade contain a certain amount of crystal-enclosed organic matter in addition to the presence of adsorbed organic matter. The content of the crystal-enclosed organic matter in tremolite jade is relatively lower, with a release temperature of 900-1 150℃. This organic matter is primarily composed of ammonium or magnesium salts of waxes and resins. Tremolite jade loses its greasy luster and gets whitened after the loss of crystal-enclosed organic matter. The oxidation or polymerization of the dispersed organic matter within the jade will increase the carbonyl (C=O) functional groups in the organic molecules, and the increase of unsaturated bonds will cause a conjugation effect of the organic molecules within the jade, with the fluorescence intensity being geometrically increased. Modern coal petrology employs a range of technologies, such as the fluorescence one, to microscopically identify visible dispersed organic matter in sedimentary rocks through optical microscopy. The Raman spectrometer is capable of simultaneously receiving both Raman scattered light and fluorescence because the fluorescence signal generated by laser excitation is stronger. This makes it a more suitable instrument for the identification of trace dispersed organic matter in minerals. When the 785 nm laser of a Raman spectrometer is used to irradiate jade, the fluorescence generated by carbonyl conjugation will form a hump-shaped fluorescence background in the Raman spectrum of jade. This type of fluorescent background is prevalent in jades unearthed throughout China and is particularly evident in fire-labored jades. The jade artifacts unearthed at the Sanxingdui site were discolored due to heating. This process was dependent on both the structural changes of a jade itself and the loss of dispersed organic matter within the jade. Due to the presence of burning traces in the sacrificial pits at the Sanxingdui site, the excavated whitened jades display a uniform and fine texture, accompanied by a pronounced fluorescent background in the Raman spectra. It could be surmised that the jade artifacts from the Sanxingdui site were directly buried during the burning process. The high pressure caused by the residual temperature in the pit and the vaporization of materials in a confined space after burial made it easier to release the crystal-enclosed organic matter within a jade while the integrity of jade artifacts was kept. The released organic matter was retained in the sacrificial pit. In a confined space, the elevated temperature and oxygen-deficient environment prompt the crystal-enclosed organic matter in jade to undergo polymerization and absorb some visible light, thereby inducing a transformation in the surface color of jade.

Abstract:Scholars have long been interested in the sources of metal minerals used for Xia and Shang bronzes. The pattern of lead isotopic variation in bronzes from the Xia, Shang and Zhou Dynasties has been largely clarified, but the widespread use of the lead addition process has resulted in lead isotopic data primarily indicating the sources of lead materials, while the provenances and variation of copper materials remain unclear. This study gathered the published trace element data of Xia and Shang bronzes and conducted a multivariate statistical analysis, revealing similarities of the trace element data between bronzes excavated from Erlitou and the Erligang phase of Zhengzhou, which showed a similar pattern of variation to that of the lead material, and implied an inheritance of copper and lead materials used for Xia and Shang bronzes. The trace elements of the Upper and Lower Erligang bronzes did not change significantly, indicating that the source of the copper material had not shifted during the period, whereas the lead material changed from the low ratio lead to the highly radioactive one. There were many similarities of the trace elements between Erligang-phase bronzes from Zhengzhou and those from Panlongcheng, suggesting that the copper material had been circulated between the two locations. The trace element differences between Erligang-phase bronzes from Zhengzhou and those from the late Shang sites of Xiaohucun, Yinxu and Sanxingdui were significant, and differed from the continuity of lead material shown by the highly radioactive lead, suggesting a significant shift in the provenance of copper material from the early to the late Shang Dynasty. The similarity of trace element data of bronzes excavated from different sites in the Central Plains during the Yinxu period suggests that there was not only a sharing of highly radioactive lead material between different areas during that time, but also circulation of some copper materials between them. However, different copper materials may have been used at sites in Shandong, northern Shaanxi and the Chengdu Plain. The continuation of similar copper material from Erlitou to the Erligang period, and the shift in the provenance of copper material from the Erligang to the Yinxu period coincide with the mining and abandonment of the Zhongtiao Mountain copper mine, implying that the copper material from Erlitou to the Erligang period was primarily produced from the mine. The copper material shift during the Yinxu period may be attributed to the large-scale copper mining activities in the middle and lower reaches of Yangtze River, such as Tongling and Tonglushan.

Abstract:Tomb M75 at Xitou site, Xunyi County, Shaanxi Province belongs to the middle period of the Northern Wei Dynasty, and the tomb owner may have come from a nomadic Xianbei group living on the northern edge of the Guanzhong Basin. Inside the coffin chamber of the tomb, a round cap-shaped amber ornament was found around the tomb owner’s head area, which may have been used as part of a headdress or necklace. Similar amber ornaments were excavated in Datong, Shanxi Province and have only been found at Xianbei tombs so far. They may be related to the specific group of people, concepts or functions, which deserve further attention. In this study, this sample was examined and analyzed using super depth-of-field microscopy, infrared spectrometry and Raman spectrometry. According to the results, this amber ornament could be confirmed as an imported Baltic amber, since its infrared spectrum showed a clear “Baltic shoulder”. It is inferred that this ornament might have been transferred to Pingcheng along the Eurasia Steppe and then passed through an uncertain route from the Yanbei region to the northern edge of Guanzhong Basin. This is the first tested sample of Northern-Wei-time ambers to acquire its clear provenance, and this study provides new materials and reliable temporal and spatial nodes for in-depth discussions on the spread of Baltic ambers during the early Middle Ages.

Abstract:To clarify the materials and manufacturing technique for a lacquer Lian discovered from a Han tomb in Xianyang, Shaanxi Province, scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), micro-Raman spectrometry, Fourier transform infrared (FTIR) spectrometry, and X-ray diffraction (XRD) were used to study the lacquering technique, chemical composition of the lacquer film, and the decoration materials for the lacquer Lian fragments. The analytical results indicate that the Jiazhutai technique was used to make the lacquer Lian, with two layers of plain linen fabric being the inner matrix. The lacquer-ash layer was composed of quartz, albite, muscovite, and hydroxyapatite. Most interestingly, the existence of hydroxyapatite suggests that powdered bone was added in the lacquer-ash layer. Cinnabar and an iron-containing material were utilized to redden and blacken the lacquer film respectively. The latter may have been added into the lacquer intentionally to acquire the effect no later than the Han Dynasties. The FTIR result reflects that lacquer film was made with raw lacquer. In addition, metal plates decorated on the lacquer Lian surface were made of silver, which were embedded. The silver plates were seriously corroded, and the corrosion products were mainly silver chloride. This research plays an important role in supplementing the information of materials, manufacturing technique, and surface decoration method for Han Dynasty lacquerware in the Guanzhong region of China.

Abstract:In order to study the lacquering techniques used for the coffin excavated from the Xinzhuang No.1 Chu tomb of the Warring States Period in Pingdingshan, Henan Province, and to provide a corresponding scientific basis for conservation and restoration, several methods, including 3D video microscopy, scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), Fourier transform infrared (FTIR) spectrometry, and Raman spectrometry, were used to analyze the cross-section and composition of lacquer film of the intermediate and the inner coffin, which was preserved in good conditions. The results reveal that the lacquer film of the inner coffin was mainly divided into four layers (the wood layer, the lacquer layer, the pigmented surface layer, and the painted layer), and that of the intermediate coffin was mainly divided into three layers (the wood layer, the lacquer layer, and the red pastels surface layer). There was no ash layer in the lacquer film of the coffin. The main component of lacquer film was raw lacquer, and that inside the inner coffin was raw lacquer and tung oil. The pigment of the red film was cinnabar, the yellow pastel was pararealgar, and the black layer was raw lacquer. The results of this study could provide reference for the restoration of lacquered wooden coffins of the Warring States Period.

Abstract:The brocade with the flower and hunting pattern of the Tang Dynasty unearthed from Damago, Qira, Hotan, Xinjiang needs to be conserved and restored scientifically due to its poor condition, which includes cracking, incompleteness and creasing. Before restoration, disease investigation and condition recording were carried out. Through infrared (IR) spectrometry and observation of appearance and horizontal cross-section, it was determined that the brocade was woven with silk. The results of IR spectrometry and scanning electron microscopy (SEM) show that the degree of deterioration of the warps was obviously more serious than that of the wefts. Microscopic observation results show that the fabric structure was weft brocade with a twill weave. Color values and codes of the wefts were recorded through color value measurement and color chart comparison. Possible dyestuffs used for the brocade were analyzed preliminarily based on data of high-performance liquid chromatography (HPLC). A plan for the conservation and restoration was formulated according to the above investigation and testing results. Considering the restoration requirement for keeping both front and back sides in their original appearance, a needle and thread stitching method was utilized to reinforce the brocade, along with an inlay-support method for building a stable storage microenvironment. After conservation and restoration, the silk threads were secure and the overall firmness of the brocade was obviously improved, making the collection, moving and display of the brocade more convenient, exactly meeting the restoration team’s expectations. The entire work provides a good model for the conservation and restoration of similar cultural heritage objects in the future.

Abstract:Through the observation and analysis of 11 literati calligraphy and painting fans of the Ming and Qing Dynasties from Sichuan Museum, this study probed into disease causes and processing techniques for this kind of cultural relics. It was found that the fan surface was composed of three layers:a filler layer, a hydrophobic layer, and a base paper layer. In the early Ming Dynasty, the processing technique for the surface of gold fans was initially complicated, but then it was gradually simplified. The simplification of the processing procedure reflects the Ming and Qing fan level and technical evolution, which is consistent with the relevant literature:mud gold fans→fans with various coating processes (such as gold sprinkling, porcelain blue)→alum fans (coated solely with a hydrophobic layer)→Fenlian paper fans. Fan relics mainly suffer from the fracture of the fan crease and diseases of the filler layer, the degree of disease being affected by the thickness, coating material and technique. The surface coating had good hydrophobicity, so the ink-absorbing property was bad (that of the gold surface was generally worse than that of the plain one) and writing and printing pigments did not adhere to it well. According to the results of X-ray fluorescence (XRF) spectrometry and scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), the fillers were silicate compounds with the stable chemical properties, not vulnerable to ambient temperature and humidity, so the fillers could effectively improve the insect-and mildew-proofing abilities of fans. However, the fillers were more affected by adhesives—aging and degumming of adhesive could result in many diseases such as peeling, cracking, hollowing, pulverizing and warping of the filler layer. The “gold” on the surface was mainly a gold and silver alloy. Different ratios of gold to silver and three different processing forms allowed it to generate different metallic colors and luster. Therefore, it is difficult to reduce the chromatic aberration in the restoration process using the traditional pigment blending method. The technical characteristics and diseases of the fan surface are different from those of ordinary paper calligraphy and paintings, so it is difficult to achieve the desired restoration effect if using the restoration techniques for traditional calligraphy and paintings.

Abstract:Mural paintings and other painted cultural relics are precious cultural heritage with great artistic value and historical significance. The pigment is an important part of the information on the surface of a mural painting, and it is extremely important to identify the pigment type quickly and accurately. Due to the non-renewable nature of cultural relics, the use of non-destructive means of detection has become necessary. The hyperspectral technology has become an important research tool for identifying mural pigments due to its advantages of non-destructive detection, high spectral resolution, as well as the union of imagery and spectrum. In this study, a pigment identification method using Euclidean distance (ED) combined with the normalized spectral characteristic index (NDSI) is proposed to address the problem of differentiating pigments with the same color in murals. Firstly, seven green mineral pigments, including atacamite, verdigris, green agate, turquoise, ultramarine green, malachite, and mica green, were selected and painted on rice paper to form samples. We obtained their reflectance in the wavelength of 350-2 500 nm using an ASD FieldSpec4 spectroradiometer. Secondly, the spectral first-order derivatives were utilized in the selection of characteristic bands, which can highlight the curve trend. In this case, the bands with a derivative value of 0 are the peaks and troughs of a curve, which can be considered as characteristic bands. Taking the atacamite pigment as the target pigment, for the i-th characteristic band of atacamite pigment, we calculated the sum of the Euclidean distances between atacamite and other pigment spectra in this band to obtain the distance index D_i corresponding to the i-th characteristic band. The distance indices for all characteristic bands were sorted in a descending order, and the four bands corresponding to the top four largest distance indices were selected as the final characteristic bands of the target pigment. Then, the NDSI was constructed using these characteristic bands, which are given by NDSI=12R_a-R_bR_a+R_b+R_c-R_dR_c+R_d, where R_a, R_b, R_c and R_d are the reflectance values of the characteristic bands respectively. Fifteen NDSI values can be obtained by permutations and combinations between bands. In order to select the optimal NDSI, the distinction between the 15 indices was calculated, which is given by Q=, Where q is the NDSI value of the target pigment and W is the index value calculated by substituting the NDSI formula of the target pigment into the spectra of other pigments. We assume that indices greater than 0.5 can distinguish the target pigment from other pigments. We have simultaneously applied the maximum-minimum selection method here. When the minimum distinction of a certain index for all pigments is the highest among all indices and the distinction is greater than 0.5, the index is considered as the optimal NDSI for the target pigment. Finally, NDSIs were constructed for all green pigments using the above steps. In addition, we selected optimal NDSIs for red, yellow and blue pigments at the same time in the experiments. In order to verify the accuracy of the spectral feature indices selected for the experiments, a laboratory simulated mural was firstly used as the validation data. The spectra of pigments at seven points on the surface of the simulated mural were collected for pigment identification using NDSI, spectral angle mapping (SAM), ED, spectral feature fitting (SFF), and binary encoding (BE), respectively. The results show that the method was capable of distinguishing between pigments of the same color category compared to other spectral matching methods, improving the accuracy of pigment identification. In order to verify the applicability of NDSI on real mural artefacts, the pigments on the surface of the mural paintings on the east wall of Cave 6 of Yungang Grottoes, Shanxi Province, China were selected as the validation data. By using NDSI, we found that the pigment of the blue area was lazurite, and the pigments of three red areas were cinnabar for one and red lead for two. The identification results were basically consistent with the detection results of Raman spectrometry. In summary, the pigment identification method proposed in this paper for pigments of the same color category could quickly extract the pigment feature information and carry out pigment identification with higher accuracy, which is of practical significance for the identification and differentiation of pigments of the same color category in murals. However, it is hard to identify mixed pigments using NDSI, a problem that needs to be improved upon future studies.

Abstract:In order to explore the effects of illumination, humidity and carbon dioxide volume fraction on paper cultural relics in terms of diseases, an experimental system for environmental parameters and diseased paper samples was established, and a fiber-optic spectral sensor and its detection system were also constructed. The experimental results show that 1) the adverse effects of blue-violet light and red light on the paper samples were stronger than that of yellow light—the paper samples irradiated by the blue-violet light and red light suffered from the photochemical decomposition of cellulose due to a thermal effect; 2) after the treatment at low humidity, the cellulose of paper samples shrank; after the treatment at high humidity, a large number of molds grew on the sample surface, causing corrosion and biochemical reactions; 3) the acid hydrolysis reaction of cellulose in paper samples under the action of high volume fraction of carbon dioxide caused the morphological characteristic changes of paper samples, and decrease of both tensile strength and thermal stability. After the diseases of the paper samples occurred, the output signal of the fiber optic spectral sensor showed a characteristic absorption peak at 275 nm; when mold microorganisms were attached to the paper sample surface, the characteristic absorption peak shifted to 300 nm. The results highlight that a temperature of 26℃, yellow light, relative humidity of 55%, and a low volume fraction of carbon dioxide were beneficial to the preservation of paper cultural relics.

Abstract:In this study, scientific methods, including surgical microscopy, infrared photography, and macroscopic X-ray fluorescence (MA-XRF) scanning imaging for multiple surface scans, in combination with a Raman spectrometric fiber optic probe and the fiber optic reflectance spectrometer point testing method were used to test the painting of Pines and Cranes Rejuvenation Scroll by Giuseppe Castiglione, a famous Qing court painter. The results show that 1) the pigments used for the painting included carbon black, ochre, lead white, cinnabar, malachite and others; 2) in terms of toning, carbon black and ochre were mixed for drawing brunet contour lines and trees, and a Western painting tradition—the use of lead white for the base before the application of carbon black, malachite, cinnabar and other pigments for superficial color drawing of the main scene in a painting—was followed; 3) in terms of drawing techniques, the stereoscopic effect of painting was highlighted by the use of different pigments from the same color system, alteration of the ratio between pigments from the same color system, and application of different drawing methods. The combined use of multiple surface detection methods and point detection methods demonstrates the utility of using scientific research to obtain information about traditional Chinese scroll paintings, such as pigment types, toning methods, and drawing techniques. The analytical results are of great significance for revealing the value of works.

Abstract:Due to the limitations and complexity of ancient ceramic restoration materials, there is a risk of damage to porcelain having many defects due to the deviation of the center of gravity. Meanwhile, due to the difference in material structure and mechanism and other factors, it is difficult for restoration materials to achieve the same texture as that of ancient ceramics. In this study, a Yuan Dynasty blue and white twinned branch peony cloud dragon plate collected by Jingdezhen Ceramic University was taken as an example. Based on the material characteristics of the plate body, the compatibility analysis of complementary materials was carried out based on the transmittance, density, hardness, etc. Finally, it was confirmed that the adhesive suitable for the plate was Hxtal (YL-1), and the complementary materials were 200 mesh, 800 mesh and 3 000 mesh alumina mixed with the Red Star 509 epoxy glue, these being the closest to the process characteristics of Yuan blue and white porcelain. The results further demonstrate the utility of scientific application of ancient ceramic restoration materials. Based on following the principles of restoration, the security risks of cultural relics are not only reduced, but the display of artifacts is also improved.

Abstract:In order to help the restoration and conservation of the Zhaxi Conference site, and to understand the timber-using habits of ancestors in southern Sichuan and the degradation of wooden components, the wooden components of the Zhaxi Conference site, which was originally built in 1835, were appraised using the method of timber anatomy to identify the species, and the degree of degradation was evaluated using fluorescence polarization in combination with physical properties. The results show that the window frames were made of Cupressus spp. (Cupressaceae), the foot beaming and weatherboards were made of Pinus spp. (Pinaceae), the floorboards were made of Picea spp. (Pinaceae), and the beaming and columns were made of Cunninghamia spp. (Taxodiaceae). Cypress, pine and fir are distributed in Weixin County, indicating that the residential buildings were mainly made of “local materials”. Window frames were the most severely degraded, followed by the beaming, and the rest of the ancient wooden components were not significantly different from the modern timber in terms of degradation. The degree of degradation of a wooden component is related to its tree species and location, with termites, sunlight and rainwater being the main causes of degradation of wooden components.

Abstract:For the conservation of museum objects on display, it is important to monitor environmental risks and locate risk variables in a timely way. However, due to the differences of exhibition halls for various cultural relics, it is difficult to apply the environmental risk classification criteria for a particular exhibition hall to other exhibitions, or even to different types of cultural relics in the same exhibition hall. In addition, when a risk appears, a museum may not find the influencing factors in time, which prolongs the length of time of the risk. Therefore, in combination with the continuous monitoring data of the temporary exhibition “Jiangnan Culture and Art” in Shanghai Museum, a two-level monitoring framework for environmental risk state assessment of paper cultural relics has been proposed. The risk monitoring is carried out by four levels, namely “excellent, good, medium and poor” according to the demands. Firstly, a principal component analysis (PCA) model is established using the “excellent” dataset and the control limit is constructed to select “excellent” data. The control limit of “poor” data is obtained using the existing PCA model. Then, a ReliefF-PCA model is established using the “non-excellent and non-poor” dataset and the control limit of “good” and “medium” classification is obtained. Finally, a contribution plot and a weighted contribution plot based on the ReliefF algorithm are used for the corresponding PCA model and ReliefF-PCA model respectively, thus quantifying the risk and initially locating the risk variables that have an impact on the environmental indicators. The monitoring framework constructed by the two evaluation models provides a more scientific scheme for the evaluation of the environmental quality of cultural relic preservation and the subsequent adjustment of the museum environment. This is helpful for improving the efficiency of the whole cultural relic conservation system.

Abstract:Crack disease is widespread in stone cultural relics, and brings great challenges to their preservation. Therefore, it is important to carry out in-depth research on crack disease for the conservation of cultural relics. In this study, through the use of infrared thermal imaging technology, both indoor model tests and field test research for crack detection of stone cultural relics were carried out. The influence of the crack on the temperature field of rock mass was studied with the crack opening width being a main variable. The results show that 1) the active thermal excitation method was effective in crack detection; 2) the thermal inertia of the air in the fracture was large, causing the temperature change at the fracture to lag; 3) a cooling index was introduced in this study to quantitatively evaluate the temperature change rate of the sample, and had a good negative correlation with the fracture area ratio, which was verified by the field test results. These research results have preliminarily achieved the goal of quantitative detection of apparent cracks in stone cultural relics.

Abstract:Microbial damage is ubiquitous in archaeological excavation sites and museums of ancient ruins. Effective prevention and control of microbial activities act as an important prerequisite for the long-term preservation and display of earthen sites. This paper systematically summarizes the research status of microbial deterioration and its treatment for earthen sites both at home and abroad, combs relevant basic theories, research methods, prevention and control measures and the frontier progress, and compares the advantages and disadvantages of current research methods toward microbial deterioration and conservation of earthen sites. This study may provide a new perspective and reference for the scientific and technological conservation of earthen sites.

Abstract:Bamboo and wooden slips were the main carriers of ancient Chinese literature before the widespread use of paper. Due to the complex underground burial environments vulnerability to decay of bamboo and wood materials, and human factors in the process of excavation and after excavation, bamboo and wooden slip manuscripts often have many diseases. Based on the practice of conserving bamboo and wooden slips on the front line, the results of literature research, and the observation of a large number of bamboo and wooden slips, more in-depth, comprehensive, systematic, and accurate analysis and sorting of the disease types of bamboo and wooden slip manuscripts were conducted for the first time. The diseases of bamboo and wooden slip manuscripts can be divided into a total of 29 types, including blurred handwriting, soft rot, plaque, water logging, decay, crispy powder, discoloration, deformation, carbonization, etc. A brief summary was also made on the corresponding conservation measures for various types of diseases. Scientifically summarizing the types of diseases in bamboo and wooden slip manuscripts and the corresponding conservation measures has important reference value for understanding the preservation status of bamboo and wooden slips in a scientific way, clarifying the weak aspects of bamboo and wooden slip conservation, promoting the introduction of specialized disease classification and conservation industry standards for bamboo and wooden slips, and thus developing better conservation plans for bamboo and wooden slips.