Heritage Science最新文献

The safety of rock landscapes in Mount Wuyi is significantly impacted by acid rain and wet-dry cycles. In this paper, the decay characteristics of the physical–mechanical properties of red glutenite were investigated under acidic wet-dry cycles. A systematic approach, including cold field emission scanning electron microscopy (CFE-SEM), image processing techniques, and X-ray diffraction (XRD), was proposed to investigate the damage mechanism of red glutenite under acidic wet-dry cycles. The results indicate that with increasing solution acidity and wet-dry cycles, dry density (DD), longitudinal wave velocity (LWV), uniaxial compressive strength (UCS), and elastic modulus (EM) of red glutenite significantly decrease. Under different acidic conditions, DD, LWV, and UCS exhibit exponential decay with wet-dry cycles, while EM exhibits linear decay. A regression fitting was employed to establish a prediction model for UCS, which exhibited a better capability in predicting the correlation between UCS, pH, and the number of wet-dry cycles. Microscopic comprehensive analysis reveals that the interaction between rock dissolution and desiccation is the primary factor leading to changes in the microstructure and mineral composition of red glutenite, culminating in the decay of its physical–mechanical properties. This study holds significant guidance implications for the preservation of cultural and natural heritage in Mount Wuyi.

This study aims to characterise the so-called Sialkoti paper used to produce Pahari drawings preserved today in the Wereldmuseum in Leiden (Netherlands) (WML). These works originate from the Punjab Hills in India (today Himachal Pradesh) and are commonly known as ‘Pahari miniature paintings’. The paper upon which these drawings are executed is said to have been produced in Sialkot during the eighteenth and nineteenth centuries when papermaking was an integral part of an overall regional economy correlated with other sectors such as agriculture and the textile industry. Although the term Sialkoti refers to identified papermills in Sialkot (now Pakistan), the paper from this region is yet to be subjected to a systematic study. This article therefore explores the paper(s) in question through macro- and microscopic observations of structure, pulp and fibres. The study of historical sources, complemented by the analysis of paper samples and fibre identification, has revealed that the pulp would have been prepared from a variety of manufactured products using different technologies, such as rags, cloth, mats, rope and other plant-based materials made from local bast fibres which, once tattered, were recycled to prepare the pulp. Microscopic study reveals that a variety of fibre combinations under different conditions and processing steps were used, in particular sunn hemp fibre (Crotalaria juncea L.), a plant species that has until now rarely been identified in historical paper. In addition, the presence of kenaf and jute fibres, as well as a significant quantity of cotton fibres, have also been demonstrated. To overcome the lack of comparative materials, our work was supported by a comparative study of several materials made from sunn hemp now held in the Ethnobotany Collection at Kew Gardens. Samples were taken from these materials and provided useful reference micrographs for the identification of the WML samples. The quality of the paper used by Pahari artists, as well as the raw materials available and their processing, are discussed in detail. Putting all the data, including technical and historical information into perspective, we conclude that the Pahari artists used a paper of inferior quality compared to other types of paper used for other purposes such as the creation of illuminated manuscripts in the Punjab plains. This study therefore provides useful analytical and material evidence that complements previous historical, technical and anthropological studies.

Deep learning-based inpainting models have achieved success in restoring natural images, yet their application to ancient paintings encounters challenges due to the loss of texture, lines, and color. To address these issues, we introduce an ancient painting inpainting model based on dual encoders and contextual information to overcome the lack of feature extraction and detail texture recovery when restoring ancient paintings. Specifically, the proposed model employs a gated encoding branch that aims to minimize information loss and effectively capture semantic information from ancient paintings. A dense multi-scale feature fusion module is designed to extract texture and detail information at various scales, while dilated depthwise separable convolutions are utilized to reduce parameters and enhance computational efficiency. Furthermore, a contextual feature aggregation module is incorporated to extract contextual features, enhancing the overall consistency of the inpainting results. Finally, a color loss function is introduced to ensure color consistency in the restored area, harmonizing it with the surrounding region. The experimental results indicate that the proposed model effectively restores the texture details of ancient paintings, outperforming other methods both qualitatively and quantitatively. Additionally, the model is tested on real damaged ancient paintings to validate its practicality and efficacy.

Micro lime, hydrated lime (Ca (OH)₂) with particle sizes of 1-3μ dispersed in isopropanol, can be used to reinforce deteriorated earthen structures. The consolidation effect depends on the amount of moisture present in the structure or in the ambient air. This study investigates the influence of different levels of relative humidity (RH) on the consolidation effect of micro lime on earthen structures, the chemical processes responsible for the consolidation and the physical changes to the structure. The aim is to gain a deeper understanding of the underlying chemical reactions and to identify a potential limit to the applicability of this consolidation method in low RH environments. The fact that many of these sites are located in arid climates greatly influences the practical application of micro lime in the conservation of historical earthen structures. To characterize the consolidation effect of micro lime, unconfined compressive strength and exposure to wet and dry cycles were used. The properties of the reaction products and the bonding between soil particles and micro lime were investigated using thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM). At RH levels of 25%, 45%, 65% and 90%, the unconfined compressive strength (UCS) and the modulus of deformation at 50% strength (E₅₀) of the micro lime-reinforced specimens demonstrated an increase with humidity. This led to a significant improvement in their ability to resist the effects of dry–wet cycles. Results from thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) indicate that micro lime interacts with the soil matrix via carbonation, with the reaction rate increasing with humidity. At 25% RH, vaterite was produced and residual free lime was observed, whereas at humidity levels of 45% and above, the reaction yielded vaterite and aragonite. The lime treatment did not significantly alter the pore structure of the soil specimens. The total porosity of the specimens was only slightly reduced, with the main effect of the lime treatment being a reduction in the number of large pores.

Building information modeling (BIM) can greatly improve the management and planning of historic building conservation projects. However, implementing BIM in the heritage has many challenges, including issues with modeling irregular features, surveying data occlusions, and a lack of predefined libraries of parametric objects. Indeed, surface features can be manually distinguished and segmented depending on the level of human involvement during data scanning and BIM processing. This requires a significant amount of time and resources, as well as the risk of making too subjective decisions. To address these bottlenecks and improve BIM digitization of building geometry, a novel deep learning based scan-to-HBIM workflow is used during the recording of the historic building in historic Jeddah, Saudi Arabia, a UNESCO World Heritage site. The proposed workflow enables access to laser scanner and unmanned aerial vehicle imagery data to create a complete integrated survey using high-resolution imagery acquired independently at the best position and time for proper radiometric information to depict the surface features. By employing deep learning with orthophotos, the method significantly improves the interpretation of spatial weathering forms and façade degradation. Additionally, an HBIM library for Saudi Hijazi architectural elements is created, and the vector data derived from deep learning-based segmentation are accurately mapped onto the HBIM geometry with relevant statistical parameters. The findings give stakeholders an effective tool for identifying the types, nature, and spatial extent of façade degradation to investigate and monitor the structure.

The Tianshanbeilu cemetery is the largest Bronze Age cemetery in eastern Xinjiang, China, and plays important roles in connecting the Eurasian interior to the Hexi Corridor, and further to the Central Plains region. Utilizing micro-XRF and Raman spectroscopy techniques, we identified a fluorite bead at this cemetery. This barrel bead is the earliest record of such a fluorite bead in China, dating back to approximately 1385–1256 BCE. Comparing the unearthed records of fluorite beads in eastern China spanning from the Neolithic Age to the Western Zhou dynasty, we notice that in the early Western Zhou period, fluorite beads found in élite burials are only in barrel or biconical shapes, both of which first appeared in the eastern region of Xinjiang, such as the Tianshanbeilu cemetery in Hami and the Yanghai cemetery in the Turpan Basin. We proposed that the barrel fluorite bead drilled by metal tubular drill first appearing in the Tianshanbeilu cemetery might have spread eastward to the Central Plains region and finally constituted a component of the ritual revolutions during the Western Zhou dynasty.

Data scarcity in paleographic image datasets poses a significant challenge to researchers and scholars in the field. Unlike modern printed texts, historical manuscripts and documents are often scarce and fragile, making them difficult to digitize and create comprehensive datasets. Recently many innovations have been arrived on single image generative models for natural images but none of them are focused on paleographic character images and other handwritten datasets. In paleographic images like stone inscription characters, maintaining exact shape and structure of character is important unlike natural images. In this paper we propose an unconditional single image generative model, CharGAN for isolated paleographic character images. In the proposed system, augmented images are generated from a single image using generative adversarial networks, while maintaining their structure. Specifically, an external augmentation inducer is used to create higher-level augmentations in the generated images. In addition, the input to the generator is replaced with dynamic sampling from a Gaussian mixture model to make changes to the low-level features. From our experimental results, we infer that these two enhancements make single-image generative models suitable not only for natural images, but also for paleographic character images and other handwritten character datasets, the AHCD dataset, and EMNIST, where the global structure is important. Both the qualitative and quantitative results show that our approach is effective and superior in single-image generative tasks, particularly in isolated character image generation.

Bronze artifacts often suffer from “bronze disease” due to the presence of chloride ions, which result from copper chlorides forming on their surfaces during storage. Therefore, reinforced protection is essential for these unearthed cultural artifacts, and new materials for the reinforced protection of fragile bronzes are urgently needed. In this study, cuprammonium solvent and nanocellulose (CNC) were utilized as reinforcement materials to protect fragile bronzes. The chemical and aesthetic properties before and after reinforcement were analyzed using ultra-depth field microscopes, SEM-EDX, XRD, and Raman spectroscopy. The results indicated that at a nano-cuprammonium reinforcer concentration of 2.5 mol/L, the optimal reinforcement effect on simulated bronze powdery rust samples was achieved.Mechanical strength increased by an average of 77.59%. The mass growth rate reached 84.8%, while the color difference (Delta E) remained below 4.0. Additionally, aging resistance significantly improved, aligning with cultural artifact protection standards.Meanwhile, a compact and stable protective membrane formed on the surface of the bronzes, isolating the bronze matrix from direct contact with the external environment, which delayed bronze corrosion and contributed to long-term stable preservation.

Graphical Abstract

In addition to his astronomical observations the famous Renaissance astronomer Tycho Brahe (1546–1601) was known also for his interest in alchemy. He equipped his castle Uraniborg on the island of Ven with a state-of-the-art alchemical laboratory when it was erected around 1580. After Brahe’s death Uraniborg was demolished upon a royal decree from 1601, a process which was completed around 1650. In the present study we have analysed four glass shards and one ceramic shard most likely from the alchemical laboratory and retrieved during an archaeological excavation in 1988–90. Cross sections of the shards have been analysed for 31 trace elements by Laser Ablation Inductively Coupled Plasma with Mass Spectrometry with the aim of detecting any traces of the chemical substances on the inside or outside of the shards used in the laboratory. Four of the elements found in excess on the exterior surfaces of the shards, Cu, Sb, Au, and Hg, are in accordance with the reconstructed recipes of the three Paracelsian medicines for which Brahe was famous—Medicamenta tria. This is the first experimental data casting light on the alchemical experiments that took place at Uraniborg 1580–1599.

A novel combined measurements techniques has been designed in this work, enabling the acquisition of laser-induced breakdown spectroscopy (LIBS) and Raman spectral signals at the same point on a sample. The application of this combined technique to the analysis of multi-layered mock-up blocks painted with orpiment and realgar pigments has yielded significant insights. By correlating variations in the emission line intensity of characteristic elements within the LIBS spectra with depth-specific Raman spectra, the number of laser pulses that penetrated the pigment layers has been accurately determined, thereby establishing a method to measure layer thickness. Finally, the technique wasto analysis the actual mural fragment from Mogao Cave 196, determining the types of pigment and the thickness of the pigment layers.

Graphical Abstract