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The practical application of the electrocatalytic CO2 reduction reaction (CO2RR) to form formic acid fuel is hindered by the limited activation of CO2 molecules and the lack of universal feasibility across different pH levels. Herein, we report a doping-engineered bismuth sulfide pre-catalyst (BiS-1) that S is partially retained after electrochemical reconstruction into metallic Bi for CO2RR to formate/formic acid with ultrahigh performance across a wide pH range. The best BiS-1 maintains a Faraday efficiency (FE) of ~95 % at 2000â mA cm-2 in a flow cell under neutral and alkaline solutions. Furthermore, the BiS-1 catalyst shows unprecedentedly high FE (~95 %) with current densities from 100 to 1300â mA cm-2 under acidic solutions. Notably, the current density can reach 700â mA cm-2 while maintaining a FE of above 90 % in a membrane electrode assembly electrolyzer and operate stably for 150â h at 200â mA cm-2. In situ spectra and density functional theory calculations reveals that the S doping modulates the electronic structure of Bi and effectively promotes the formation of the HCOO* intermediate for formate/formic acid generation. This work develops the efficient and stable electrocatalysts for sustainable formate/formic acid production.
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Objectives: To assess the association of bronchoalveolar lavage fluid (BALF) α-SMA and ß-catenin levels and the severity of pneumonia. Methods: The records of patients with severe pneumonia treated in our hospital from June 2019 to June 2020 were selected. The clinical outcome was observed within 10 days. For the purpose of analysis, patients were divided into two groups according to the outcome, 47 cases in the improvement group and 39 cases in the deterioration group. The intubation time, mechanical ventilation time and APACHE II score 10 days after admission were compared between the two groups; We assessed pulmonary infections using the clinical pulmonary infection score(CPIS). The levels of α-SMA and ß-catenin in bronchoalveolar lavage fluid at different time points were compared and analyzed, to analyze the association between the levels and the CPIS. Results: The APACHE II score in the improvement group were lower than those in the deterioration group (P<0.05). The expressions of α-SMA and ß-catenin in the BALF of patients in the improvement group were significantly lower than those of patients in the deterioration group on day 1, 3, and 7 (P<0.05); and the expressions of α-SMA and ß-catenin in the BALF of patients in the improvement group decreased with time, while those of patients in the deterioration group increased gradually with time(P<0.05). The expressions of α-SMA and ß-catenin in patients with CPIS>6 was significantly higher than those in patients with CPI≤6(P<0.05). Pearson correlation analysis showed that the levels of α-SMA and ß-catenin in BALF were positively correlated with the CPIS. Conclusion: The levels of α-SMA and ß-catenin in BALF are closely associated with the clinical condition of patients with severe pneumonia; the levels are positively associated with the severity of the disease and they increase with symptomatic worsening.
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The relationship between anxiety and sleep disorders is a key research topic in the academic community. However, evidence on the mechanism through which anxiety influences sleep disorders remains limited. The purpose of this study was to investigate the roles of flourishing and neuroticism in the mechanism through which anxiety influences sleep disorders in medical students. We constructed a moderated mediation model and tested the mediating role of flourishing and the moderating role of neuroticism in medical college students. The results showed that: (1) anxiety was significantly and positively related to sleep disorders and significantly and negatively related to flourishing; flourishing was significantly and negatively related to sleep disorders; neuroticism was significantly and positively related to sleep disorders; (2) flourishing had a mediation effect on the relationship between anxiety and sleep disorders; (3) neuroticism moderated the process through which flourishing mediated the effect of anxiety on sleep disorders. Our research expands the literature on the mechanism underlying the effects of anxiety on sleep disorders and provides insights into the potential prevention and intervention of sleep and emotional problems in medical students.
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The field of small molecule electro-activated conversion is becoming a new star in modern catalytic research toward the carbon-neutral future. The advent of single-atom catalysts (SACs) is expected to greatly accelerate the kinetics of electrocatalytic reactions such as the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), hydrogen oxidation reaction (HOR), etc., owing to their maximum atomic efficiency, unique quantized energy level structure and strong interaction between well-defined active sites and supports. In this feature article, our group's proposed synthesis methodology applied in electrocatalysis is mainly summarized. Furthermore, we elaborate on how to achieve the stabilization of single metal atoms against migration and agglomeration during the preparation of SACs. Moreover, the electrochemical applications of SACs with a focus on the above heterogeneous reactions are presented. Finally, the prospects for the development and deficiencies of these SACs for electrocatalytic reactions are discussed.
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Cobalt sulfide@reduced graphene oxide composites were prepared through a simple solvothermal method. The cobalt sulfide@reduced graphene oxide composites are composed of cobalt sulfide nanoparticles uniformly attached on both sides of reduced graphene oxide. Some favorable electrochemical performances in specific capacity, cycling performance, and rate capability are achieved using the porous nanocomposites as an anode for lithium-ion batteries. In a half-cell, it exhibits a high specific capacity of 1253.9 mA h g-1 at 500 mA g-1 after 100 cycles. A full cell consists of the cobalt sulfide@reduced graphene oxide nanocomposite anode and a commercial LiCoO2 cathode, and is able to hold a high capacity of 574.7 mA h g-1 at 200 mA g-1 after 200 cycles. The reduced graphene oxide plays a key role in enhancing the electrical conductivity of the electrode materials; and it effectively prevents the cobalt sulfide nanoparticles from dropping off the electrode and buffers the volume variation during the discharge-charge process. The cobalt sulfide@reduced graphene oxide nanocomposites present great potential to be a promising anode material for lithium-ion batteries.