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This paper presents a novel method for fabricating three-dimensional (3D) microstructures of cobalt–platinum (Co-Pt) permanent magnets using a localized electrochemical deposition (LECD) technique. The method involves the use of an electrolyte and a micro-nozzle to control the deposition process. However, traditional methods face significant challenges in controlling the thickness and uniformity of deposition layers, particularly in the manufacturing of magnetic materials. To address these challenges, this paper proposes a method that integrates machine learning algorithms to optimize the electrochemical deposition parameters, achieving a Co:Pt atomic ratio of 50:50. This optimized ratio is crucial for enhancing the material’s magnetic properties. The Co-Pt microstructures fabricated exhibit high coercivity and remanence magnetization comparable to those of bulk Co-Pt magnets. Our machine learning framework provides a robust approach for optimizing complex material synthesis processes, enhancing control over deposition conditions, and achieving superior material properties. This method opens up new possibilities for the fabrication of 3D microstructures with complex shapes and structures, which could be useful in a variety of applications, including micro-electromechanical systems (MEMSs), micro-robots, and data storage devices.

Abstract In 2006, the Majiayuan Cemetery of the Warring States period (475 BCE to 221 BCE) was discovered in Zhangjiachuan county of Gansu province, northwest China. The thousands of exquisite gold/silver artifacts, bronze wares, potteries, and beads unearthed, and have attracted great interest when investigating the dynamics of exchange, mobility, and transcultural encounters in Eurasian artifacts. During the excavation, plenty of blue and purple faience beads were found arranged around the tomb owner in grave M52. Faience beads of the same style unearthed from other graves of the region indicate their mature production at the time of burials. By adopting scientific methods for the chemical and compositional characterization of the faience beads, this study explained their materials and production techniques and provided new insights into faience production in the late Warring States period.

Abstract This study combined various non-invasive and micro-invasive analytical techniques to investigate the production process of coffin plank paintings excavated from a Northern Wei tomb in Zhijiabao Village, Datong City, Shanxi Province. Fiber-optic reflectance spectroscopy, portable Raman spectroscopy, and portable X-ray fluorescence spectroscopy were employed for in-situ non-invasive detection of coffin panel paintings. On that basis, micro-samples in smaller amounts than that of previous studies of the same type were collected and analyzed through optical microscopy, confocal micro-Raman spectroscopy, and scanning electron microscopy-energy dispersive spectroscopy. The results showed that the studied coffin plank decoration was painted after applying a layer of yellow primer to the plank surface. Specifically, cinnabar was used as the red material, pararealgar was used as the yellow color, an indigo and orpiment mixture was used as the green substance, the blue pigment was most likely an indigo and lead white mixture, gypsum was used the white material, and carbon black was used as the black pigment. Notably, the studied coffin plank was painted with a mixture of inorganic and organic materials to present the green and blue colors. This study provided not only a scientific basis for the conservation and restoration of this artifact but also new information for the research on Northern Wei art history.

Abstract As non-renewable cultural heritage, wall paintings play an important role in society. To reveal the trends in the scientific analysis of mural paintings, 845 relevant research articles published from 2011 to 2021 were collected from the Web of Science database and analyzed. The VOSviewer software was adopted to map the network data of scientific publications, so that relationships among authors, countries, institutions can be displayed, and the co-occurrence of keywords and co-citation can be analyzed. The results revealed close and strong interconnections between the top authors, suggesting a considerable strong research link in this field. The cooperation between research institutions was relatively close. The most productive country of relevant publications was Italy. The leading journals for the scientific analysis of wall paintings were Journal of Raman Spectroscopy and Journal of Cultural Heritage. At present, the hotspots of scientific analysis and research on wall painting are revealing the composition, distribution, origin, and deterioration mechanism of pigments, alongside with evaluating the effects and mechanism of conservation materials and techniques. On the one hand, a possible development direction in this field is introducing more cutting-edge analysis and data processing methods. On the other hand, scientific analysis is increasingly adopted to guide the research and development of mural conservation materials.

Abstract Located in Pujiang, Chengdu, China, more than four hundred artifacts were unearthed during the excavation of the Warring States (the Warring States period lasts from 475 to 221 BC) ship-shaped graves in 2016. The compositional and metallurgical feature of the unearthed vessels are still unclear. Archaeologists and conservators are puzzled by such problems that need to be answered by systematic scientific studies. Fifty one samples, either from the matrix (26 samples), or from the corrosion part (25 samples) of 25 unearthed bronze vessels, were carefully collected from the fallen part of the bronze vessels for analysis. Technical methods, such as OM, SEM-EDS, XRD and Raman Spectroscopy were adopted for compositional and metallurgical characterization of the bronzes, as well as identification of the corrosion products. The bronzes are Cu–Sn–Pb trinary alloys with typical casting microstructure. The proportion of Sn are in accordance with excavated bronze vessels in surrounding areas. Recycling isn’t involved with the production of such vessels. Layered structure of the corrosion products was observed. Different corrosion products were identified as Cu2CO3(OH)2, Cu2O, CuSO4·5H2O SnO2, PbSO4 and PbCO3. The findings help us gain insights into the bronze manufacturing in Bashu district, as well as the corrosion behavior in certain condition.

Abstract In this paper, a comparative study was conducted on the extraction effects of six agents for collagen-based mural painting binders. These agents were used to extract the residual proteins in the non-aged and thermal aged samples. The protein extraction efficiencies of different extracting agents were quantitatively determined by bicinchoninic acid (BCA) method, and then processed by multivariate analysis of variance (MANOVA). The impact of the extraction process on the protein structure was characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), ultraviolet absorption spectrum (UV) and circular dichroism (CD). The results showed that, for both non-aged and aged samples, the extraction efficiency of 2 M guanidine hydrochloride (GuHCl) was significantly higher than the other five agents, with less damage to the protein structure during the extraction process.

Abstract Historically, sutras played an important role in spreading Buddhist faith and doctrine, and today these remain important records of Buddhist thought and culture. A Mahamayuri Vidyarajni Sutra with polychrome paintings was found inside the cavity on top of the Nanmen Buddhist pagoda, built in the early Tang dynasty (618–627 CE) and located in Anhui Province, China. Textile was found on the preface which is strongly degraded and fragile. Unfortunately, the whole sutra is under severe degradation and is incomplete. Technical analysis based on scientific methods will benefits the conservation of the sutra. Optical microscopy (OM), micro-Raman spectroscopy combined with optical microscope (Raman), scanning electron microscopy in combination with energy dispersive X-ray analysis (SEM–EDS) and Fourier Transform Infrared Spectroscopy (FTIR) were used to characterize the pigment and gilded material, as well as the paper fiber and textile. Pigments such as cinnabar, minium, paratacamite, azurite, lead white were found. Gilded material was identified as gold. A five-heddle warp satin, made of silk, was found as the textile on the preface of the sutra. The sutra’s preface and inner pages were made of paper comprised of bamboo and bark. As a magnificent yet recondite treasure of Buddhism, the sutra was analyzed for a better understanding of the material. A conservation project of the sutra will be scheduled accordingly.

Abstract In order to accurately identify the ancient liquid contained in the plum vase excavated from Jurou Li’s Grave of the Jin Dynasty (1115–1234 CE) in Xi’an, mass spectrometry was applied to determine the amino acid sequences of the residual proteins extracted from the liquid sample. The sequences were searched against a standard protein sequence database. The proteins extracted was identified as glycosyltransferase from Sorghum bicolor, calcium-dependent protein kinase 2 from Wickerhamomyces ciferrii, and cytochrome b-c1 complex subunit Rieske from Nadsonia fulvescens. These findings indicate that the extremely degraded liquid in the plum vase was made from the cereal of sorghum by alcoholic fermentation of Wickerhamomyces ciferrii and Nadsonia fulvescens, providing direct evidence for liquor in the Jin Dynasty.

The Kizil Cave-Temple Complex has been registered as a World Heritage site and was formerly a part of Kucha—one of the most powerful and prosperous regions of ancient China. The No. 1 Cave is of great significance due to its three surviving clay sculptures. The mural paintings inside the cave are experiencing severe degradation. Scientific methods such as optical microscopy (OM), scanning electron microscopy combined with energy dispersive X-ray analysis (SEM-EDS), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and X-ray diffusion (XRD) were applied to analyze the pigments and organic coating used in the No. 1 Cave. The results show that paratacamite, gypsum, and lapis lazuli were used as the green, white, and blue pigments, respectively. Poly-n-butyl methacrylate (PBMA) was used as an organic coating of the blue pigment and has accelerated the aging of the mural paintings. This study shares insights into the materials and techniques employed and assesses the preservation status of the mural paintings, providing scientific support for protection and restoration schemes.

In this study, metallurgical microscope, scanning electron microscope in combination with energy dispersive X-ray analysis (SEM-EDS), Raman spectrometer and X-ray diffractometer (XRD) were used to analyze the craft, alloy composition and corrosion products of the Warring States bronze vessel "Fu" excavated from Pujiang county, Chengdu city of China (the Warring States period lasts from 475 BC to 221 BC). The results showed that the bronzes were casted and made of lead-tin bronze, the content of tin and lead were relatively high. The corrosion products of the bronzes are mainly cassiterite, malachite, hematite and lead ore. This article provides a scientific basis for the study of ancient bronze culture and for the conservation of such cultural relics. [ABSTRACT FROM AUTHOR]