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Based on the wide application of sulfur hexafluoride (SF6) gas in the power industry, the analysis and detection of its decomposition components have become important technical means for state detection and fault evaluation of gas-insulated equipment. The gas-sensitive characteristics and adsorption mechanism of the SnS2 sensor for SO2 and SOF2 gases were investigated using SO2 and SOF2, the main SF6 decomposition components, as the target detection gases. SnS2 gas-sensitive materials and components were prepared, and the temperature response, concentration response, response recovery and stability of the SnS2 sensor for the two SF6 decomposition components were tested based on the gas-sensitive test platform. The results demonstrate that the sensor had the best working performance at 200 °C, with obvious response and ideal recovery for both target gases and good stability in a certain time. Based on the first principle, the SnS2 surface structure model and the target gas adsorption model were established, and the adsorption mechanism was analyzed in terms of frontier molecular orbital theory to verify the correctness of the gas-sensitive test results. The gas-sensitive test analysis and simulation calculation can provide data basis and theoretical support for the study of SF6 decomposition components detected by gas sensors. [ABSTRACT FROM AUTHOR]

In this paper, the first-principles theory is used to explore the adsorption behavior of Ni catalyst decorated PtSe2 (Ni-PtSe2) monolayer toward the dissolved gas in transformer oil, namely CO and C2H2. Some Ni atoms from the catalyst are trapped in the Se vacancy on the pure PtSe2 surface. The geometry configurations of Ni-PtSe2 monolayer before and after gas adsorption, the electronic property of Ni-PtSe2 monolayer upon gas adsorption, and the sensibility and recovery property of Ni-PtSe2 monolayer are explored in this theoretical work. Through the simulation, the E ad of CO and C2H2 gas adsorption systems are calculated as −1.583 eV and −1.319 eV, respectively, both identified as chemisorption and implying the stronger performance of the Ni-PtSe2 monolayer on CO molecule, which is further supported by the DOS and BS analysis. According to the formula, the sensitivity of Ni-PtSe2 monolayer towards CO and C2H2 detection can reach up to 96.74% and 99.91% at room temperature (298 K), respectively, which manifests the favorable sensing property of these gases as a chemical resistance-type sensor. Recovery behavior indicates that the Ni-PtSe2 monolayer is a satisfied gas scavenger upon the noxious gas dissolved in transformer oil, but its recovery time at room temperature is not satisfactory. To sum up, we monitor the status of the transformer to guarantee the stable operation of the power system through the Ni-PtSe2 monolayer upon the detection of CO and C2H2, which may realize related applications, and provide the basis and reference to cutting-edge research in the field of electricity in the future. [ABSTRACT FROM AUTHOR]

Background: The interactions between fibroblasts and bronchial epithelial cells play important roles in the development of chronic obstructive pulmonary disease (COPD). Interleukin (IL)-17A triggers the activation of fibroblasts and the secretion of inflammatory mediators, which promotes epithelial-mesenchymal transition (EMT) in bronchial epithelial cells. Fibroblasts secrete C-X-C motif chemokine ligand 12 (CXCL12), which specifically binds to its receptor, C-X-C motif chemokine receptor 4 (CXCR4) to mediate inflammatory responses. This study aims to investigate IL-17A- and CXCL12-induced airway remodeling., Methods: Primary lung fibroblasts were isolated from human and murine lung tissue for the in vitro experiments, and a mouse model of cigarette smoke (CS)-induced COPD was established for the in vivo experiments. The results were analyzed using a one-way analysis of variance and Tukey's test or Bonferroni's test for the post-hoc test. A p -value < 0.05 was considered statistically significant., Results: Through in vitro experiments, we found that IL-17A-activated primary lung fibroblasts secreted CXCL12 and stimulated EMT in bronchial epithelial cells. However, these effects could be blocked by neutralizing IL-17A or CXCL12. In vivo, an anti-IL-17A antibody or a CXCR4 antagonist could reverse the degree of EMT in the lungs of the COPD mouse model. The IL-17A-induced EMT and increased CXCL12 expression occurred via extracellular signal-regulated kinase (ERK)/phosphorylated-ERK pathways., Conclusion: This study showed that exposure of mice to CS and IL-17A stimulation upregulated CXCL12 expression and induced EMT by activating the ERK signaling pathway. These data offer a novel perspective regarding the molecular mechanism of CXCL12/CXCR4 signaling in IL-17A-induced EMT related to airway remodeling., (JCOPDF © 2024.)

Detecting the composition and concentration of SF 6 decomposition products is an effective method to evaluate the state of gas-insulated switchgear. Based on density functional theory, in this work we investigated the adsorption properties of four typical SF 6 decomposition products (H 2 S, SO 2 , SOF 2 , SO 2 F 2 ) on an SnS 2 S vacancy structure (SnS 2 -S v ) and SnS 2 edge structure (SnS 2 -edge). By calculating the adsorption energy, charge transfer, and comparing the density of states (DOS) of each system before and after the adsorption of gas molecules, the physical and chemical interactions between SnS 2 with different structures and gas molecules were investigated. The results show that SnS 2 -S v has the largest adsorption energy for SO 2 and has obvious chemical interactions. The S vacancy can effectively capture an O atom in SO 2 , causing SO 2 to firmly adsorb in the S vacancy. In addition, the adsorption of the four gases on the SnS 2 -edge is physical adsorption, in which the 50% S edge structure has the largest adsorption energy for H 2 S, reaching -0.52 eV, and there is also a large charge transfer between the 50% S edge structure and H 2 S. Although the adsorption energy of SnS 2 -edge to the four gases is smaller than SnS 2 -S v , it is still greater than the pristine SnS 2 . This paper explores the adsorption properties of SnS 2 -S v and SnS 2 -edge for SF 6 decomposition products, providing insights for the development of SnS 2 -based gas sensors., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)