Abstract:It is reported that the bronze artifacts stained with the “bronze disease” contain multiple corrosion layers, and the chlorine-containing corrosion product is typically located in the inner layers adjacent to the matrix. Physical methods can only often remove the chlorine-containing corrosion product on the surface of the objects; however, it is particularly difficult to involve the chlorine element deep in the corrosion layer. The sodium sesquicarbonate method is a common and safe treatment for the stabilization of “active” bronze artifacts. Since the 1970s, most of the literature has mainly focused on providing a brief introduction to the method, with limited in-depth research and discussion. In this study, taking the stabilizing process by the use of sodium sesquicarbonate for an early Shang Dynasty bronze Jue as a case study, and combining analytical measures such as Raman spectrometry and ion chromatography, we reviewed and evaluated the range of application, efficacy and rule of chloride release process of the method. After a soaking treatment for 158 days and a subsequent tracking observation for 65 months, no fresh corrosion product was found, indicating excellent results. The study shows that in the absence of constant temperature and humidity control, the sodium sesquicarbonate method is still an effective method for stabilizing serious corroded bronzes, especially for large-scale outbreaks of the “bronze disease”. It is crucial to monitor chloride concentration to determine the replacement time of the solution and endpoint of the stabilizing treatment. Generally, the stabilization process can be divided into three stages:the first wash would extract approximately 73% of the total; the second wash about 19% and the third wash the remaining 8%. At the last stage, the chloride ion concentration in the solution decreased to lower than 50 mg/L. The average daily chloride ion concentration was maintained at about 3 mg/L, and the change in chlorine removal was small, indicating that the stabilizing treatment could be complete. Additionally, samples were meticulously collected from the “active” rust on the surface layer and those in the inner layer, which contained either amorphous or nanocrystalline SnO₂. Employing Raman spectrometry, we tracked both the transformation process and extent of the “active” rust. The results show that the “active” rust in the inner layer was more difficult to transform than that in the surface layer, and frequent replacement of the washing solution could reduce the possibility of new phases being formed. Dechlorination transformation is a rather complex process that requires further in-depth research in the future. The present study takes the practical conservation treatment for cultural relics as a case study, and in comparison with previous literature, it has extensions in two aspects:first, it tracked and monitored the entire dechlorination process, and evaluated the dechlorination efficacy at each distinct stage for the method; second, it traced and detected the phase transition process of the “active” rust to summarize the chlorine removal degree at different depths of corrosion layers. This study provides valuable insights into the prediction of replacement time of the solution and endpoint of the stabilizing treatment with the sodium sesquicarbonate method.

Abstract:Bronze ware, having high historical, artistic and scientific value, plays an important role in metal cultural relics. However, due to the characteristics of natural materials themselves and the influence of the burial environment, most bronze artifacts unearthed from archaeological sites or cemeteries have been seriously degraded and corroded. The corrosion of bronze ware can be divided into two types—harmful rust and harmless rust; the latter is relatively stable and harmless to bronze artifacts. However, “powdery rust” is severely detrimental to bronzes, and can make the bronzes crumble and rot, thereby seriously affecting the life of the relics. Furthermore, powdery rust also has a certain spreading power, which can cause damage to the bronze relics themselves and the neighboring ones. Therefore, we attempted for the first time to introduce low-temperature plasma technology as a means of removing powdery rust from bronzes. Bronze samples with powdery rust on the surface were prepared by electrochemical corrosion. Then the samples were treated with low temperature plasma in a reducing atmosphere. Comparison of data of bronze samples before and after the treatment shows that the low-temperature plasma technology could effectively remove chloride ions in the powder rust. This study could provide a new idea and method for the conservation of bronze relics.

Abstract:Maintaining appropriate temperature and humidity to minimize the negative effect of the environment are basic requirements for the preventive conservation of cultural relics in museums. Because of regional climate differences, sometimes adopting a uniform standard is neither necessary for relics nor energy efficient. This paper discusses a risk assessment method for controlling temperature and humidity in the museum environment of bronze relics. A quartz crystal microbalance was used to carry out reactivity monitoring experiments of the simulated bronze material, to thus obtain corrosion data. Machine learning algorithms were used to establish a highly accurate corrosion rate prediction model of the simulated bronze material under specific temperature and humidity conditions. Then, using the corrosion rate as a quantitative indicator of risk, a continuous environmental temperature and humidity risk standard was proposed for four classes. Because of a difference in atmospheric pressure, a relative humidity conversion factor was added to expand the scope of its application. A graphical user interface tool was designed to make it easier to utilize. Based on the proposed assessment standard for museum temperature and humidity risk of bronze relics, a conservator could control the temperature and humidity according to local conditions while maintaining the risk level.

Abstract:Many bronzes have been unearthed from Han tombs in Guangzhou, but their corrosion and mineralization are very serious. In order to study the mechanisms of corrosion, metallographic analysis, SEM-EDS, XRD of corrosion products, soil pH measurement and soluble salt determination were used. Typical samples extracted from bronze ware were analyzed with regard to three aspects:matrix, corrosion products and soil. The results show that there are two kinds of materials in eight of samples, namely seven pieces of lead-tin bronze and one piece of tin bronze. The mechanical properties of the alloy were not the best because of the fluctuation of the ratio of lead to tin. According to the microstructure of the matrix, most of the samples were cast microstructure. The dark field demonstrated that the mineralization corrosion process was from inside to outside. The XRD results show that all lacked copper chloride. The content of chloride ion in the burial environment of Guangzhou is not low compared with other areas in China, but the acidity is the strongest. The lead and tin in the ternary alloy were anodes relative to copper. There were a lot of intercrystalline and grain boundaries in dendrites and the potentials of different phases were different. There were a lot of inclusions and much shrinkage, the chemical composition was not uniform, the impurity potential of the alloy was higher than that of the matrix, and a lot of microcathodes and microanodes were formed. However, the main corrosion process of bronze vessels unearthed from Han tombs in Guangzhou area was H⁺ corrosion. The acidic soil environment, due to the abundant groundwater in Guangzhou, as well as abundant oxygen and carbon dioxide make copper and lead ions move outwards continuously, which results in serious corrosion and mineralization of bronzes.

Abstract:Iron anchors of the Ming and Qing Dynasties excavated offshore in Penglai have been affected by the marine environment, showing serious surface corrosion and obvious shedding of the rust layer. This deterioration has not only impacted their aesthetic appearance but also compromised the structural integrity of the anchors. To assess corrosion levels and evaluate preservation strategies, we employed ultra depth-of-field 3D microscopy, scanning electron microscopy with energy-dispersive spectrometry (SEM-EDS), laser confocal micro-Raman spectrometry (Raman), and X-ray diffraction (XRD) in this study. The results show that the primary rust components on the anchor surfaces were iron hydroxides and oxides. The rust layers displayed clear stratification:the compact inner black rust layer consisted mainly of Fe₃O₄ and goethite (α-FeOOH), while the outer porous rust layer was comprised of α-FeOOH, β-FeOOH, and hematite (α-Fe₂O₃). Also seen was the presence of poorly stabilized uneven rust γ-FeOOH on the peeling surface of the rust layer and the substrate. Elemental chlorine was detected in all the iron anchor rust samples. The distribution of soluble chlorine ranged from 0.66 to 35.46 mg/g, with large differences in soluble chlorine content among the different samples. The soluble chlorine content of the rusted iron anchors preserved in the museum was higher than that of the rusted iron anchors in the open environment. The iron anchors exhibited pitting attack index (PAI) values ranging from 1.16 to 13.34, with consistently lower PAI values observed in the inner rust layers compared with the outer layers, indicating lower stability in the inner rust layers. In order to better conserve these iron anchors as cultural relics, targeted dechlorination of chlorine-containing iron anchors will be needed in the subsequent conservation. Monitoring and regulating the preservation of iron anchors and controlling the temperature and humidity of the environment should be conducted in the daily work in order to avoid further corrosion of iron anchors. This study contributes valuable scientific insights into the preservation and restoration of Penglai iron anchors, and has significant implications for safeguarding marine-recovered iron artifacts, in general.

Abstract:Yuquan Iron Pagoda, one of the Key National Cultural Relic Protection Units, is seriously corroded. Exploring the corrosion mechanism of its surface and the corrosion evolution process could provide technical support for subsequent conservation and restoration of the iron pagoda. By analyzing the surface atmospheric corrosion of modern cast iron within 1 300 days and that of the iron pagoda after 963 years, a structure of the corrosion layers of the cast iron within 1 300 days of atmospheric corrosion and that of the iron pagoda after 963 years were explored. Additionally, a corrosion model of Yuquan Iron Pagoda suitable for the cast iron with a long period (963 years) was deduced according to the abovementioned structures. The morphology, composition, corrosion layer structure of the surface corrosion products of the cast iron and iron pagoda samples were analyzed by means of the weight measurement and digital photography, SEM, XRD and laser Raman spectrometry. Moreover, the corrosion resistances of the samples were tested by electrochemical impedance spectrometry. The results show that the corrosion weight loss and corrosion time accorded with power exponential function. The corrosion products of cast iron and iron pagoda were composed of Fe₃O₄, γ-FeO(OH), α-FeO(OH), α-Fe₂O₃, and the early corrosion was mainly distributed in thin water film. Besides, the later corrosion product layers were distributed in several layers. The α/γ value of measurable rust layer protection and the corrosion resistance of the corrosion layers were gradually increased. The decreases of the contents of γ-FeO(OH) and Fe₃O₄ and the increase of the content of α-FeO(OH) were the main reasons for the structural transformation of cast iron and iron pagoda corrosion layers.

Abstract:The fluid vapor film, as a new type of outdoor ironware sealing material, has a great potential in the application to the sealing of large-scale outdoor iron cultural relics. A new fluid vapor film sealing material suitable for outdoor iron cultural relics in most northern regions was developed through experiments and was applied to the surface sealing of ancient Ming and Qing artillery pieces. The results indicate that the new fluid vapor film had a good sealing effort, with the uses of 50A acrylic resin as the main film-forming agent, L18NF as the vapor phase corrosion inhibitor, fatty acid salt as the rust inhibitor and 12311 as the auxiliary agent. Either a water-based solvent system or an organic solvent system could be used for the new fluid vapor film, but the organic solvent system was more suitable for outdoor conditions in winter in the north. A composite brushing method utilizing ordinary brushing and matte brushing was adopted, which not only had a good rust prevention effect, but also reduced the reflectivity of the sealed surface. The new fluid vapor film method has the characteristics of being easy to operate and remove, resistance to cracking, salt spray, moisture, heat and impact, thus effectively preventing rust on the surface of iron cultural relics.

Abstract:The iron artifacts unearthed from Qingshiling Mountain City in Gaizhou, Liaoning Province, are severely damaged and contained a large amount of harmful rust. During the process of desalination of ironware using alkaline solutions, the pH value and chloride ion concentration of the soaking solution were dynamically tracked and monitored throughout the entire process to guide the soaking time and total desalination times. During the monitoring of desalination process, it was found:that as chloride ions were released, the pH value decreased; especially in the early stages of desalination, as a large amount of chloride ions were dissolved, the pH value rapidly decreased, and the soaking solution sometimes changed from alkaline to acidic in a short period of time; and that to avoid corrosion of ironware in the acidic environment, it was necessary to monitor the pH value of the desalination solution during the desalination process and replace it with a new solution in a timely manner. We have noted some practical precautions to be taken when using the NaOH solution desalination method, in order to achieve the goal of removing as many harmful chloride ions as possible in order to effectively conserve the ironware. In practice, it has been verified that using sufficient desalination cycles and other appropriate methods, the NaOH solution method could achieve almost complete conversion of β-FeOOH and almost complete removal of the chloride ion.

Abstract:Ancient wooden shipwrecks excavated from the marine environment are a significant part of cultural heritage. Investigating the degradation characteristics of waterlogged archaeological wood from shipwreck remains is not only crucial to study the mechanisms of wood decay in buried underwater environments, but also essential for the development of conservation techniques tailored to waterlogged wooden cultural relics. The degradation of waterlogged archaeological wood exhibits variability. This study focused on the waterlogged Dipterocarpus sp. wood remains from the archaeological excavation of the Xiaobaijiao Ⅰ, an ancient Chinese shipwreck. Internal and external sampling was conducted to explore the degradation characteristics. In this study, comprehensive characterization methodologies, including physical parameters analysis, optical microscopy (OM), polarized light microscopy (PLM), scanning electron microscopy (SEM), attenuated total reflectance-Fourier transform infrared spectrometry (ATR-FTIR), and dynamic vapor sorption (DVS) were employed to characterize the degradation differences between the internal and external parts of waterlogged archaeological wood. The results indicate that there was significant degradation difference between the internal and external parts of waterlogged archaeological wood, with the degraded areas clearly divided into the “outer layer” and “inner core”. The maximum water content (MWC) of the outer layer wood reached 687%, while the MWC of the inner core wood was 246%. The outer layer of wood was severely degraded, with the majority of the cells heavily decayed, and the birefringence of cellulose crystals having disappeared; furthermore, the secondary wall of the wood fibers exhibited a porous “spongy” structure, while only the middle lamella remained intact. The inner core wood was moderately degraded, with intact wood fiber cells coexisting with decayed cells, presenting the decay pattern of erosion bacteria. The FTIR results revealed that the residual chemical components in the cell walls of the outer layer of wood primarily consisted of lignin, while the inner core wood retained partial cellulose. The combination of FTIR spectrometry and principal component analysis (PCA) enabled accurate identification of severely and moderately degraded types. PCA loading curve analysis confirmed that cellulose was the main chemical component that distinguished the degradation difference between the outer layer and inner core wood. The hierarchical clustering analysis (HCA) of FTIR spectra identified the existence of a degradation transition zone between severely and moderately degraded wood. DVS analysis revealed the difference in moisture sorption properties between the outer layer and inner core wood. The Hailwood-Horrobin model was utilized to fit the sorption isotherms, allowing for the calculation of monolayer and multilayer adsorbed water contents in wood samples exhibiting various degrees of degradation. The results indicated that the equilibrium moisture content of the outer layer wood was higher than that of the inner core wood. This disparity was primarily attributed to the difference in the porous structure of the wood cell walls and cellulose content between the outer layer and inner core wood. Specifically, the porous cell wall structure of the outer layer of wood facilitates an increase in monolayer adsorbed water content, while the higher cellulose content in the inner core wood results in an elevation in multilayer adsorbed water content. This study employed a comprehensive analytical approach with innovations in sampling and FTIR analysis. Based on the positional differences in wood degradation, samples were collected from both the outer layer and inner core regions. By integrating chemometric analysis methods with FTIR spectrometry, the degree of wood degradation was rapidly determined on the basis of microscopic diagnosis, thereby enhancing the accuracy of assessing the preservation state of waterlogged archaeological wood. Furthermore, based on the investigation of microstructural and chemical components, the moisture sorption properties of wood cell walls at different degradation levels were characterized, and the influence of changes in cell wall structure on the hygroscopicity of waterlogged archaeological wood was further explored. This study revealed that the erosion bacteria were the main degraders for the Xiaobaijiao Ⅰ, and elucidated on the heterogeneous characteristics of degradation in shipwreck waterlogged archaeological wood, providing a perspective for understanding the mechanisms of wood decay in underwater burial environments.

Abstract:The aging of proteinaceous binders buried under soil environment may cause a change of amino acid content, thus affecting their GC-MS identification. In order to improve the accuracy of this method, the author studied how the amino acids of the commonly used binders (collagen, egg and milk) changed after aging in archaeological soil, using GC-MS box plot and principle component analysis (PCA) graph. The GC-MS results show that the levels of Pro, Asp and Glu increased while that of Ser decreased. Gly and Hyp in pig glue and Ile, Phe in egg and milk decreased. These changes caused variations in the box plot and PCA graph, but they were identifiable. Based on the above research, animal glue, and a mixture of animal glue and egg were identified in the painting layers of murals and pottery of the Tang tomb at Guodu, Xi’an. This study has improved the accuracy of GC-MS identification of proteinaceous binders and could provide a scientific basis for exploring the degradation mechanism and selecting proper conservation materials.

Abstract:Previous studies have focused primarily on inorganic artifacts such as bronze vessels, but given less attention to organic ones. This is due to the susceptibility of organic materials to decay and degradation, often resulting in their complete disappearance or survival only in forms of remnants. The plant weavings unearthed from tombs are organic artifacts, typically found in extremely poor conditions. Identification of their materials through organic residue analysis forms a basis for their subsequent preservation and the better understanding of their value. This study focused on the woven mat-like material attached to a bronze Gui from Tomb M1020 at the Beibai’e Cemetery, using three methods—fiber microscopic observation, phytolith analysis, and liquid chromatography-mass spectrometry (LC-MS)—for analysis. Plant fibers could be observed in certain areas of the mat. These fibers were generally short, slender, and exhibited some curvature, often appearing alongside epidermal cells. The observed epidermal cells were elongated and serrated on both sides, with the serrations typically being semi-elliptical in shape, tapering slightly at the top compared to the base. The undispersed epidermal cells were often connected to form a continuous layer, with the serrations interlocking like a zipper. The results of the fiber microscopic observation were consistent with the characteristics of Gramineae plants, particularly reeds. Notably, around the undispersed epidermal cells, fragments of the “reed membrane” with stomata and traces of epidermal cell arrangement were observed. The “reed membrane” was a key marker for identifying reeds. In addition, a statistical analysis of 200 phytoliths was conducted. Among the identifiable ones, over 70% were epidermal phytoliths from Gramineae, with a small number of saddle-shaped phytoliths (from Gramineae) and spinulose phytoliths also present. Among common weaving materials, two types belong to the Gramineae family: bamboo and reed. Referring to previous studies on the microscopic features of ancient reed mats as well as modern reed and bamboo, it is evident that the morphological characteristics and arrangement of the aforementioned phytoliths were consistent with those of reed stem phytoliths, but did not match the microscopic morphology of bamboo stems. The mat-like weaving unearthed from the archaeological site has undergone significant degradation of its organic components due to prolonged burial, resulting in substantial changes in the types and quantities of these components. However, it is still possible for species-specific metabolic small molecules to remain. This study utilized LC-MS to study the mat-like weaving unearthed from Tomb M1020 at the Beibai’e Cemetery, along with reagent blank controls. Compared to the total ion chromatogram of the blank controls, that of the archaeological samples had a few characteristic peaks identified, leading to the identification of 14 small molecules by searching natural product databases. Among them, gomisin O, pterosin B, and methylparaben are plant-derived metabolites, and choline, sphingosine, and phytosphingosine may be of the plant origin. These findings indicate the plant-derived nature of the archaeological samples. This study focused on the mat-like weaving attached to a bronze Gui from Tomb M1020 at the Beibai’e Cemetery. Using fiber microscopic observation and phytolith analysis, it was determined that its biological origin was reed. The plant origin was further verified through LC-MS. Additionally, by correlating the findings with historical texts and the actual conditions at the archaeological excavation site, it was inferred that the archaeological sample was a reed mat, placed between the outer coffin lid and the inner coffin lid for use as a “dust mat”. Furthermore, a large number of mat-like remnants were also found beneath the bottom board of the coffin, where they were well preserved due to their proximity to the original soil. Comparing these remnants with the scientifically analyzed archaeological samples indicates that they were also reed mats, positioned beneath the tomb owner as a “resting mat”. A large number of mat-like weaving remnants were found in Tomb M1020 at the Beibai’e Cemetery, and similar situations are also common in other tombs from the early Spring and Autumn Period. This indicates that the burial mat played an important role throughout the burial process and that the practice of using burial mats was well established during this period.  The research findings provide physical evidence of burial mats used during the early Spring and Autumn Period, contributing to a better understanding of the funerary practices of that time. In addition, they offer an entry point for reconstructing the social landscape following the Eastern Migration of the Zhou Dynasty.

Abstract:The embroidered boots of the Southern and Northern Dynasties are precious collections in Gansu Provincial Museum. Their overall shape is basically complete, but local contamination, incompleteness and decay are serious and the boots continue to deteriorate. Therefore, a conservation and restoration plan was formulated, and rescue conservation and restoration were carried out for this set of textile cultural relics. The brocade embroidered boots are three-dimensional textile cultural relics, and their conservation and restoration is more complex and difficult compared to that of flat ones. Based on the excavation and research on the cultural value such as the weaving and embroidery technology and pattern style of the brocade embroidered boots, non-destructive testing was done to determine their various diseases and causes, fabric types, dyes, contaminants, etc. Also carried out was a detailed analysis and sorting of the conservation and restoration methods used, restoration difficulties, and process flow. This study provides reference experience and an example of the conservation and restoration of three-dimensional textile cultural relics of the same type.

Abstract:In this study, a large-format X-ray fluorescence scanning imaging spectrometer (MA-XRF), a 3D video microscope and a Raman spectrometer were used to analyze and test gold and silver-decorated iron belt hooks as well as their early restoration materials. The compositions of the iron belt hooks’ material, the distribution of gold and silver foil, and the fracture loss and the crack positions were determined, and the exquisite decoration was restored. The early restoration materials for the iron belt hooks were shown to be mainly epoxy, sand and pigment for the hook head and epoxy, gypsum and pigment for the hook neck, the vicinity of the hook knob and the hook tail. The chemical structure of the epoxy used was the closest to that of the black epoxy. These results show that MA-XRF, as a new detection method, was effective in image enhancement, disease condition judgment and repair location confirmation. The combination of large-format scanning and single-point acquisition made possible the comprehensive extraction of information about the cultural relics and provides a scientific basis for making conservation and restoration plans.

Abstract:The Office of Xinhua Daily was a publishing organization established by the Central Committee of the Communist Party of China in the Kuomintang-controlled areas during the War of Resistance against Japanese Aggression until the early stage of the War of Liberation. Taking its newspaper publications collected by the Chongqing Hongyan Revolutionary History Museum as research objects and basic data in this study, we used ultra depth-of-field 3D microscopy, scanning electron microscopy, energy dispersive X-ray spectrometry, and pH measurement to detect and analyze the fiber composition, filler type, paper-making technique and paper acidity of the samples. Combining relevant historical materials, we found the paper used for newspaper was affected by many factors:the political and economic environment, paper-making techniques, and paper-use strategies. Both machine-made and handmade papers were used:in the early stage (from the founding of Xinhua Daily on January 11,1938 to October 24 of the same year), machine-made white newsprint was used most often; in the middle stage (from October 25,1938, when the office was relocated to Chongqing, until the victory of the War of Resistance against Japanese Aggression), improved handmade paper from Sichuan and Chongqing was gradually used; in the late stage (from the victory of the War of Resistance against Japanese Aggression to the forced closure of the office in February 1947), handmade paper was still used. This study provides reference for the conservation and utilization of the publications from the Office of Xinhua Daily and of similar cultural relics.

Abstract:There are a large number of sandstone grottoes in the Longdong area of Gansu. Affected by natural and human factors, the grottoes have various types of diseases. Through a systematic survey of samples from provincial and national heritage conservation units, the sandstone grottoes in Longdong area were divided into three regions, namely the Jing River Basin, the Pingding River area and the Liupan Mountain area, according to the topographic features. The instability of rock mass, water erosion and superficial weathering have all developed in the study areas. In the Jing River Basin, the instability of rock mass was mainly manifested by the development of unloading cracks and joints. There were also problems of slope instability, such as collapse and landslide, with the collapse scale being generally larger and there being roof collapse diseases in large caves. There were many types of water erosion, the main diseases being water seepage, wetting in the grotto and cliff erosion. With regard to superficial weathering, powdering exfoliation, efflorescence, crust and alveolization were widespread; the second cause was the biological disease, mainly reflected by microorganisms and lichen moss cover. In the Pingding River area, the instability of rock mass was mainly caused by the falling of small pieces of rock and the collapse of the roof. The water erosion was of many types and of small scale, such as water seepage, dampness and erosion at the foot of the slope. The superficial weathering was also prevalent, and powdering exfoliation and recess erosion were more serious. In the Liupan Mountain area, the instability of rock mass was not developed, although there was some collapse of the roof. Water erosion was relatively undeveloped, with erosion on the cliff and a small amount of water seepage. The superficial weathering was less developed, with surface crust spalling and uneven surface discoloration being the most prominent. The results of the study have important implications for guiding research and planning for grotto conservation.

Abstract:The Lower Yangtze Valley is one of the key regions to explore social complexity and the origins and development of Chinese civilization. Also, the interaction between the increasing social complexity and the regional subsistence economy also brings in a critical issue in archaeology. Shanghai plays an important part in the archaeological cultural sequence of the Lower Yangtze Valley, the zooarchaeology of which will cast light on human-land relationships, subsistence changes and social shifts in past societies. This paper reviews the zooarchaeological studies conducted at pre-Qin sites in Shanghai. There are seven archaeological sites the zooarchaeological results of which have been published, namely the sites of Songze, Fuquanshan, Wujiachang, Yaojiaquan, Jianghai, Maqiao and Guangfulin. Although these sites were excavated at different times and the faunal databases had been open to the public to various degrees, we re-analyzed the faunal data of each site respectively and, based on them, unveiled several characteristics regarding animal procurement and exploitation strategies in Shanghai from the Neolithic Age to pre-Qin periods. First, the strategy of animal procurement and exploitation in pre-Qin Shanghai was the result of environmental adaptation. Archaeological sites of the pre-Qin periods were located closer to the coastline than in modern days. It is central to understanding how ancient residents in Shanghai had adapted to the surrounding environment and exploited the local resources. Employing “site catchment analysis,” the surrounding environments which were exploited by ancient residents in Shanghai are categorized into six groups:woods, bushes, wetlands, freshwater bodies, saltwater bodies and human settlements. Animals, such as deer, living in the woods and bushes were most frequently exploited. Highly diverse animal resources were available in wetlands. The hypothesis of the rice-fish farming system in wet paddy fields was partially supported by discoveries of fish and reptile taxa adapted to paddy fields and phytolith results from Songze and Maqiao. The exploitation of wetlands corresponded to the subsistence economy centred around the wetland system in the Lower Yangtze Valley. Marine resources were available at sites near the coastal line. However, there have been scarce discoveries of marine fish bones in Shanghai, likely due to the limited employment of sieving and floating during the excavations. Low-level livestock husbandry was practised at human settlements. It is evident that pigs and dogs were domesticated. Nevertheless, it remains unclear whether the buffalo bones recovered from the Songze, Yaojiaquan, Guangfulin and Maqiao sites belong to domesticated or wild species. Multidisciplinary studies integrating geometric morphometrics, stable isotopic analysis and aDNA analysis will help clarify the domestication story of the local taxon. Second, animal procurement and exploitation in Shanghai were consistent with the general subsistence pattern in the Lower Yangtze Valley during the pre-Qin periods. From a regional perspective, subsistence in the Lower Yangtze Valley displays a changing pattern varying in the proportion of wild animal reliance versus livestock husbandry. The Liangzhue and Maqiao cultures, both found in Shanghai, are two turning points in this process. During the Songze cultural period, residents in Shanghai mainly relied on wild mammals for meat. Meanwhile, domesticated pigs and dogs were kept at a relatively lower level. The reliance on wild animals along with limited utilization of domesticated animals was extended into the Liangzhu cultural period in Shanghai. This result largely fits in the regional mosaic pattern in the Lower Yangtze Valley where agriculture and livestock husbandry were intensified in the political centre around the Liangzhu ancient city and hunting and fishing remained the major lifeway in peripheral regions including Shanghai. Later in the Maqiao cultural period, the hunting and fishing tradition in the subsistence economy continued, being unlikely to be influenced by the collapse of Liangzhu. It is worth noting that during the Maqiao period, the targeted prey species shifted from deer to wild boar. This dietary preference for pork might have formed together with the development of pig husbandry and been retained in the hunting and fishing lifestyle thereafter. To sum up, the archaeological sites in Shanghai during the pre-Qin periods were very likely to be small self-sufficient villages relying mainly on wild animal resources and supplemented by low-level livestock husbandry. Ancient residents in Shanghai took advantage of the local environment and exploited surrounding natural resources. Looking forward to future research, we hope that new archaeological data from recent excavations could be published in time, zooarchaeological studies from neighboring regions could be further strengthened, and multidisciplinary studies encouraged. By doing so, we aim to move towards a more comprehensive, in-depth and detailed understanding of the subsistence in ancient Shanghai against the regional economic and ecological background in the Lower Yangtze Valley.

Abstract:In terms of conservation and restoration, the silicate material is one of the most important materials for inorganic cultural relics, and also belongs to indispensable materials for ancient buildings and ancient sites, because of its high strength, durability, adaptability, etc. Therefore, it has been widely used for the conservation and restoration of movable cultural relics (such as clay sculpture, pottery, porcelain, iron, bronze, bone, paper, and textile) and immovable ones (such as murals, earthen sites, and ancient masonry buildings). This paper introduces the applications of six common natural, synthetic and composite silicate materials to the conservation and restoration of cultural relics. It also discusses in detail their application technology and specific cases for the conservation and restoration of cultural relics. Finally, it analyzes the effects of implementation of the corresponding conservation and restoration technology, and looks forward to the development prospects of silicate materials for the conservation and restoration of cultural relics.

Abstract:This paper summarizes the fiber composition analysis methods for ancient paper relics. It introduces the principles and development of polarized light microscopy, electron microscopy, pyrolysis gas chromatography-mass spectrometry and Fourier transform infrared spectrometry. It also discusses their advantages and limitations, and provides representative uses of these methods. In applications, the combined use of various methods could be more accurate to analyze the fiber composition of paper relics.