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As an important elemental analysis method, laser-induced breakdown spectroscopy (LIBS) enables the qualitative and quantitative determination of the compositions of geological targets on Mars. In order to analyze the chemical compositions of Martian rocks and soils at Gale crater, the ChemCam team built a LIBS spectral library of 408 geological standards using a ChemCam's ground replica under a simulated Martian atmosphere. However, the lack of spectra data with component labels makes it difficult to establish a composition inversion model for predicting the collected spectra. The Mars Surface Composition Detector (MarSCoDe) carried by China's Mars rover, Zhurong, also employs LIBS technology and has successfully conducted related composition detection work. Therefore, this paper proposes a domain-adaptive fully connected neural network (DAFCN) capable of transferring prior knowledge between ChemCam and SDU-LIBS (a LIBS system developed by Shandong University). The model extracts the features of the source domain and target domain through a three-layer fully connected network and uses a domain adaptation function to reduce the difference in feature distribution between the source domain and target domain. Experimental results show that the proposed method is superior to the traditional method without migration. Further, we tried this method to establish the connection between MarSCoDe and other LIBS devices, and then quantitatively analyzed the spectra collected by MarSCoDe. [ABSTRACT FROM AUTHOR]

Studying the influence of oxygen on the growth and properties of diamond has research significance. In this paper, we created an oxygen-rich environment by adding Ni2O3 to the Fe–Ni–C system. Large single crystals of oxygen-containing diamond were successfully synthesized using the temperature gradient method (TGM) in a China-type large volume cubic high-pressure apparatus (CHPA) at 5.5–6.0 GPa and 1360–1600 °C. The results show that with the increase of the Ni2O3 content in the Fe–Ni–C system, the rate of diamond growth decreased while the conditions for diamond growth were enhanced. The morphology of the diamonds changed from {111}, {110} and {113} mixed faces to {111} dominant face. The IR results show that the presence of Ni2O3 increased the nitrogen content in diamonds from 237 ppm to 543 ppm. When 3.5 wt% Ni2O3 was added, A-centre nitrogen began to appear in the diamonds. The XPS results confirmed that oxygen successfully entered the diamond lattice in the form of C–O, C＝O, O–C＝O and N–O with a high concentration of Ni2O3 additives. Meanwhile, there were no obvious impurity inclusions and cracks in the diamond crystals. In addition, the Raman peak position of the diamond appeared to red shift, and the FWHM increased from 4.93 cm−1 to 5.52 cm−1. [ABSTRACT FROM AUTHOR]

Carbon capture, utilization and storage (CCUS) have been projected by the power and industrial sectors to play a vital role towards net-zero greenhouse gas emissions. In this study, we aim to explore the feasibility of a global chemical industry that fully relies on CO2 as its carbon source in 2050. We project the global annual CO2 demand as chemical feedstock to be 2.2–3.1 gigatonnes (Gt), well within the possible range of supply (5.2–13.9 Gt) from the power, cement, steel, and kraft pulp sectors. Hence, feedstock availability is not a constraint factor for the transition towards a fully CO2-based chemical industry on the global basis, with the exception of few regions that could face local supply shortages, such as the Middle East. We further conduct life cycle assessment to examine the environmental benefits on climate change and the trade-offs of particulate matter-related health impacts induced by carbon capture. We conclude that CO2 captured from solid biomass-fired power plants and kraft pulp mills in Europe would have the least environmental and health impacts, and that India and China should prioritize low-impact regional electricity supply before a large-scale deployment of CCUS. Finally, two bottom-up case studies of China and the Middle East illustrate how the total regional environmental and health impacts from carbon capture can be minimized by optimizing its supply sources and transport, requiring cross-sectoral cooperation and early planning of infrastructure. Overall, capture and utilization of unabatable industrial waste CO2 as chemical feedstock can be a feasible way for the net-zero transition of the industry, while concerted efforts are yet needed to build up the carbon-capture-and-utilization value chain around the world. [ABSTRACT FROM AUTHOR]

The faience in China suddenly appeared in the Western Zhou Dynasty (1046-771 BC), and its production is considered to be influenced by the West. In this paper, the microstructure and chemical compositions obtained by synchrotron radiation micro-computed tomography (SR-μCT) and μ-probe energy dispersion X-ray fluorescence spectrometry (EDXRF) were combined to disclose the manufacturing information of faience beads excavated from Peng State cemetery in Hengshui, Shanxi Province, China, dated to the Western Zhou Dynasty (1046-771 BC). Based on inner structural features obtained by SR-µCT, it was found that these faience beads could be divided into two types: glazed faience and glassy faience. According to the structural information revealed by the CT slices, it is inferred that these beads were first formed on an organic cylinder and then glazed using the direct application method. The possible sources of copper colorant are copper ores. In addition, the glaze chemical compositions are distinct from Na2O°CaO-SiO2 glaze or glass in the West, and thus, Western Zhou faience should have an indigenous origin in China. Furthermore, the manufacturing features are consistent with the techniques of proto-porcelain during the same time period, but the glaze recipe is distinct from that of proto-porcelain and early glass in China. Consequently, it is proposed that faience in the Western Zhou Dynasty was not the precursor of early glass in China. [ABSTRACT FROM AUTHOR]

Chinese liquors are often a very important part of social event in China. Driven by high profit, some illegal traders often use inferior liquors instead of the products with high quality to cheat the customer. Therefore, it is highly required to authenticate Chinese liquors. In this paper a novel method based on ambient glow discharge ionization mass spectrometry has been developed to differentiate Chinese liquors. Volatile components from liquor samples were ionized by the plasma generated by glow discharge and then detected by a commercial linear ion trap mass spectrometer. Consequently, the fingerprint mass spectra of several Chinese liquors were obtained. Combined with principal component analysis, this new method was successfully applied to differentiate different brands of Chinese liquors without any sample pretreatment. Compared with conventional methods, this novel method has the advantages of easy operation, high speed, and high efficiency, which make it a potential tool in the fields of food safety, atmosphere chemistry. [ABSTRACT FROM AUTHOR]