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Single atom catalysts (SACs) have attracted broad research interest in recent years due to their importance in various fields, such as environmental protection and energy conversion. Here, we discuss the mechanisms of CO oxidation to CO2 over single Ag atoms supported on hexagonal boron-nitride sheets (Ag1/BN) through systematic van der Waals inclusive density functional theory (DFT-D) calculations. The Ag adatom can be anchored onto a boron defect (VB), as suggested by the large energy barrier of 3.12 eV for Ag diffusion away from the VB site. Three possible mechanisms (i.e., Eley-Rideal, Langmuir-Hinshelwood, and termolecular Eley-Rideal) of CO oxidation over Ag1/BN are investigated. Due to "CO-Promoted O2 Activation", the termolecular Eley-Rideal (TER) mechanism is the most relevant one for CO oxidation over Ag1/BN and the rate-limiting reaction barrier is only 0.33 eV. More importantly, the first principles molecular dynamics simulations confirm that CO oxidation via the TER mechanism may easily occur at room temperature. Analyses with the inclusion of temperature and entropy effects further indicate that the CO oxidation via the TER mechanism over Ag1/BN is thermodynamically favorable in a broad range of temperatures.

Co-thermal chemical conversion of coal and biomass is one of the important ways to realize efficient and clean utilization of coal. In this study, a typical Ningdong coal-Yangchangwan bituminous coal and cow manure were used to study the synergistic effect of intrinsic alkali, alkaline earth metals (AAEM) and organic matter on the co-gasification of coal and biomass by thermogravimetry analyzer (TG). The results showed that AAEM had obvious synergistic promotion effect on the gasification of a bituminous coal-cow manure mixture in the isothermal gasification (1000 ℃), whereas the organic matter will show the opposite effect on the process. To further investigate the effect of organic matter on the gasification process, the influence of organic matter on non-isothermal (25-1000 ℃) gasification reaction was investigated with heating rate of 10 ℃ /min, the kinetic parameters of the gasification reaction were obtained by Coats-Redfern method. The increase of biomass mass fraction in the sample facilitates the migration of alkali metals from the material to the solid phase. The possible mechanism of the synergistic effect of intrinsic AAEM/organic matter on the co-gasification process was proposed. [ABSTRACT FROM AUTHOR]

Based on the cohesive zone model (CZM), a finite element model of the film–substrate bearing system in the rolling–sliding contact state is established. Through analyzing the normal and tangential bearing states of the film–substrate system, the effects of the sliding–rolling ratio and the film–substrate adhesion strength on the interfacial stress and the interfacial energy release rate of the film–substrate system are studied. The results show that there is an almost symmetric stress distribution at both sides of the contact zone in rolling contact. In rolling–sliding contact, obvious shear flow along the rolling–sliding direction occurs at the front edge of the contact zone, which results in a significant increase in the shear stress at the interface at the front edge of the contact zone, increasing the risk of interface damage and delamination failure. Meanwhile, the shear flow causes a normal tensile stress concentration along the film surface behind the contact zone, which very easily causes the emergence and expansion of the film surface cracks. In addition, there is a clear positive correlation between the adhesion strength and the load-bearing capacity of the film–substrate interface. The tangential delamination damage mainly occurs at the interface regardless of the rolling or rolling–sliding contact state. [ABSTRACT FROM AUTHOR]

Sorghum (Sorghum bicolor), the fifth most important cereal crop globally, serves as a staple food, animal feed, and a bioenergy source. Paclobutrazol-Resistance (PRE) genes play a pivotal role in the response to environmental stress, yet the understanding of their involvement in pest resistance remains limited. In the present study, a total of seven SbPRE genes were found within the sorghum BTx623 genome. Subsequently, their genomic location was studied, and they were distributed on four chromosomes. An analysis of cis-acting elements in SbPRE promoters revealed that various elements were associated with hormones and stress responses. Expression pattern analysis showed differentially tissue-specific expression profiles among SbPRE genes. The expression of some SbPRE genes can be induced by abiotic stress and aphid treatments. Furthermore, through phytohormones and transgenic analyses, we demonstrated that SbPRE4 improves sorghum resistance to aphids by accumulating jasmonic acids (JAs) in transgenic Arabidopsis, giving insights into the molecular and biological function of atypical basic helix-loop-helix (bHLH) transcription factors in sorghum pest resistance. [ABSTRACT FROM AUTHOR]

Understanding the intellectual structure of geosciences is crucial for identifying emerging topics, which can guide future research and funding strategies. This study employs Latent Dirichlet Allocation (LDA) topic modeling and co-word network analysis to explore the intellectual landscape of highly cited geoscientific papers. Through empirical analysis, the study identifies 15 research areas, including climate change, geological processes, environmental impacts, and advancements in data analysis and remote sensing. These findings highlight the prominent role of big data analysis and machine learning methods across various geoscientific domains. Additionally, a notable gap has been identified in the integration of these computational methods with research on organic chemistry and formation processes, suggesting a potential direction for future exploration and innovation. [ABSTRACT FROM AUTHOR]

This study conducts a comprehensive bibliometric analysis of highly cited papers in geosciences from 2013 to 2023, examining the temporal distribution of publications, the top 20 most cited papers, categorization by Web of Science categories (WC), journal distribution, and the relationship between open access and citation frequency. The analysis reveals significant growth in geoscientific research, particularly from 2016 onwards. Highly cited papers cover diverse and multidisciplinary topics, with leading journals identified as key dissemination platforms. The study also highlights the positive impact of open access on citation rates, emphasizing the importance of accessibility in enhancing research visibility and influence. These findings provide strategic guidance for researchers and institutions aiming to maximize the impact of their scientific contributions. [ABSTRACT FROM AUTHOR]