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Doping can greatly reduce the lattice thermal conductivity of thermoelectric materials, which is considered as one of the effective ways to improve the thermoelectric properties of thermoelectric materials. First of all, we use the simple and environmentally friendly solution thermal method combined with the tube furnace sintering technology to explore the optimal temperature of sintering Cu2S in the tube furnace. When the sintering temperature reaches 700 °C, we get the thermoelectric value of 0.21. Subsequently, Cu2S thermoelectric materials doped with xmol%Sn (x = 0.5, 1, 3, 5) were prepared and the optimal concentration of Sn was explored. The Sn atom replaces the Cu atom with a smaller radius, greatly reducing the thermal conductivity of the matrix material. In the sample doped with 1%Sn, the total thermal conductivity reaches 0.31 WK−1 m−1, which is 22.5% lower than that of the pure phase sample. In addition, above 623 K, the conductivity of samples doped with 1%Sn is better than that of intrinsic samples, indicating that Sn doping can optimize the conductivity of Cu2S to a certain extent. At 773 K, the ZT of Cu2S + 1 mol%Sn can reach 0.51. 132% higher than undoped Cu2S.This provides a new idea for the preparation and commercial application of Cu–S based thermoelectric materials. [ABSTRACT FROM AUTHOR]

To explore the influencing factors of school climate, this paper used TALIS 2018 principal survey data and applied linear regression to examine the influence of three elements on school climate: external school environment and structure, principal personal characteristics, and principal leadership. According to the research targeting 198 principals from Shanghai secondary schools, all three aspects can influence the formation and development of school climate, with each influencing factor acting on different dimensions of school climate. These different paths are the mechanisms that influence the school climate in the education system. In addition, principal leadership plays a more important role than the other aspects in determining school climate. To create a school climate that is better suited to the development of all involved in the school, this paper offers suggestions on how to better select principals and improve their leadership skills. [ABSTRACT FROM AUTHOR]

In this article, density functional theory (DFT) was applied to research the structures of γ-Fe2O3 and MFe2O4 (M=Co, Cu, Zn) and to optimize the adsorption models of gases such as CO and NO onto the catalysts. Additionally, the study analyzed the CO oxidation reaction on MFe2O4 (M=Co, Cu, Zn) and the selective catalytic reduction (SCR) reaction of CO + NO in CuFe2O4 and ZnFe2O4. Results showed that CO can effectively adsorb on the reactive substrates, reacting with lattice oxygen to produce CO2 and oxygen vacancies during the CO oxidation process. γ-Fe2O3 (001) required an energy of 0.95 eV to complete the reaction, while CuFe2O4 (100) needed only 0.33 eV, offering better selectivity. In the reaction of CO + NO on CuFe2O4 and ZnFe2O4, NO adsorbed on the surface with double oxygen vacancy to form N2O2 intermediate, then reacted to produce N2 and fill the oxygen vacancy. CuFe2O4 and ZnFe2O4 required energy barriers of 0.68 eV and 0.73 eV, respectively, demonstrating the feasibility of the CO-SCR reaction on the catalyst surface. Further exploration of the reaction in an oxygen-enriched environment found that O2 can inhibit the CO-SCR reaction. The study reveals that MFe2O4 (M=Co, Cu, Zn) catalysts can improve the catalytic activity of the CO oxidation reaction and CO-SCR reaction, with CuFe2O4 exhibiting the best selectivity and catalytic activity. What's more, this study also provides insights for the simultaneous removal of CO and NO. [ABSTRACT FROM AUTHOR]

The catalytic performance of cobalt–chromium spinel NH3-SCR can be enhanced by Mn-doped and Mn–Ti co-doped catalysts; however, there is insufficient understanding of the underlying reaction mechanism. Our work is based on a first-principles computational approach of density functional theory to calculate the optimized configurations of CoAl2O4(100) both before as well as after being Mn-doped and Mn–Ti co-doped. We also simulated the adsorption behavior of gas molecules such as NH3 and NO on the catalyst before and after doping. The optimized configurations and the associated energy distributions for the NH3 dehydrogenation and SCR reactions on Mn0.1Co0.9Al2O4 and Mn0.1Co0.9Ti0.1Al1.9O4 catalysts have undergone a thorough investigation. Our findings demonstrate that the introduction of Mn-doping and Mn–Ti co-doping can enhance the adsorption capacity of gas molecules, such as NH3 and NO, on CoAl2O4 catalysts while significantly reducing the energy barriers for NH3 dehydrogenation and SCR reactions. The performance of Mn–Ti co-doping surpasses that of Mn-doping. Furthermore, we conducted an investigation into the adsorption of H2O and SO2 on the doped catalysts, revealing that Mn–Ti co-doping effectively enhances the water and sulfur resistance properties of the catalysts. Our study is anticipated to serve as a crucial theoretical guide for the development, preparation, and modification of cobalt–aluminum spinel catalysts. [ABSTRACT FROM AUTHOR]

Zinc‐ion hybrid capacitors (ZICs) are of interest for their optimal balance between power and energy density. Among the cathode materials, silicon is particularly attractive due to its abundance and potential compatibility with the microelectronics industry. However, silicon‐based materials exhibit specific capacitances far below 100 mF cm−2 because of their inherently low electronic and ionic transport, making them less competitive than other nanomaterials such as carbon and MXenes. In this study, state‐of‐the‐art silicon‐based ZICs using Mg‐doped porous silicon (PSi) derived from silica aerogels are constructed. The improved electronic conductivity achieved by Mg doping, combined with enhanced ion diffusion promoted by the porous structure, results in excellent electrochemical properties of the ZIC. Consequently, the prepared ZIC exhibits a specific capacitance of 106.1 mF cm−2 at 0.2 mA cm−2 with remarkable cyclic stability (92% retention after 20 000 cycles). Additionally, the pouch ZICs using gel electrolytes demonstrate good rate capability and a long lifespan, indicating significant potential for practical applications. These results underscore the potential of heteroatom‐doped PSi as a cathode for ZICs. [ABSTRACT FROM AUTHOR]

This study utilizes the CGSS2021 dataset to explore institutionalized political engagement among Chinese women. Key findings include positive correlations with social circle involvement, housing area, and traditional media consumption. Interestingly, younger women are less politically engaged. Cross-tabulation reveals that daily social interactions and disagreement with prioritizing marriage over career boost institutionalized political involvement, particularly in Beijing. By contrast, women from Inner Mongolia show the least engagement. Surprisingly, frequent internet usage has limited influence on political participation, whereas traditional media use boosts it. Women in their first marriage also show higher engagement. The study offers policy recommendations to enhance Chinese women's political participation. [ABSTRACT FROM AUTHOR]

Background: N6-methyladenosine (m 6 A) RNA methylation modifications have been widely implicated in the metabolic reprogramming of various cell types within the tumor microenvironment (TME) and are essential for meeting the demands of cellular growth and maintaining tissue homeostasis, enabling cells to adapt to the specific conditions of the TME. An increasing number of research studies have focused on the role of m 6 A modifications in glucose, amino acid and lipid metabolism, revealing their capacity to induce aberrant changes in metabolite levels. These changes may in turn trigger oncogenic signaling pathways, leading to substantial alterations within the TME. Notably, certain metabolites, including lactate, succinate, fumarate, 2-hydroxyglutarate (2-HG), glutamate, glutamine, methionine, S-adenosylmethionine, fatty acids and cholesterol, exhibit pronounced deviations from normal levels. These deviations not only foster tumorigenesis, proliferation and angiogenesis but also give rise to an immunosuppressive TME, thereby facilitating immune evasion by the tumor., Aim of Review: The primary objective of this review is to comprehensively discuss the regulatory role of m 6 A modifications in the aforementioned metabolites and their potential impact on the development of an immunosuppressive TME through metabolic alterations., Key Scientific Concepts of Review: This review aims to elaborate on the intricate networks governed by the m 6 A-metabolite-TME axis and underscores its pivotal role in tumor progression. Furthermore, we delve into the potential implications of the m 6 A-metabolite-TME axis for the development of novel and targeted therapeutic strategies in cancer research., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Production and hosting by Elsevier B.V.)