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A series of Ag-modified manganese-mullite (SmMn2O5) catalysts with different Ag contents (1, 3, and 6 wt.%) were prepared via a citric acid sol–gel method for catalytic soot oxidation. The catalysts were characterized by powder X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Raman spectroscopy, transmission electron microscopy (TEM), high-resolution transmission electron microscopy analysis (HRTEM), X-ray photoelectron spectroscopy (XPS), and H2 temperature-programmed reduction (H2-TPR). The soot oxidation activity of the mullite was significantly promoted by the addition of silver and affected by the loading amount of the metal. Herein, the influences of silver loading on the metal size distribution and its interactions with the mullite were studied. Based on these characterizations, a possible soot oxidation reaction mechanism was proposed for silver-modified SmMn2O5. [ABSTRACT FROM AUTHOR]

Two Mn0.15Ce0.85O2−δ mixed oxides were synthesized by a co-precipitation method using Mn(NO3)2 and KMnO4 as the manganese precursors, respectively. Structural analyses by X-ray powder diffraction and Raman spectroscopy reveal the formation of MnOx-CeO2 solid solutions. The Mn0.15Ce0.85O2−δ catalyst prepared from the high-valent manganese precursor exhibits higher activity for the catalytic oxidation of NO. The advantage of KMnO4 is related to the improved redox property of the catalyst as supported by H2 temperature-programmed reduction (TPR) and O2 temperature-programmed desorption (TPD). The Mn-Ce interactions create more Mn4+, Ce3+ and oxygen vacancies on the KMnO4-synthesized mixed oxides based on the Raman and X-ray photoelectron spectra (XPS). [ABSTRACT FROM AUTHOR]

Manganese oxides (MnOx) have attracted particular attention in the selective catalytic reduction of NOx with NH3 (NH3-SCR) because of their excellent low-temperature activity. Herein, we prepared a highly efficient MnO2 (MnO2-M) catalyst through a facile ball milling-assisted redox strategy. MnO2-M shows a 90% NOx conversion in a wide operating temperature window of 75–200 °C under a gas hourly space velocity of 40,000 h−1, which is much more active than the MnO2 catalyst prepared by the redox method without the ball-milling process. Moreover, MnO2-M exhibits better H2O and SO2 resistance. The enhanced catalytic properties of MnO2-M originated from the high surface area, abundant oxygen vacancies, more acid sites, and higher Mn4+ content induced by the ball-milling process. In situ DRIFTS studies probed the reaction intermediates, and the SCR reaction was deduced to proceed via the typical Eley–Rideal mechanism. This work provides a facile method to enhance the catalytic performance of Mn-based catalysts for low-temperature denitrification and deep insights into the NH3-SCR reaction process. [ABSTRACT FROM AUTHOR]

Graphical abstract Ce facilitates the creation of surface oxygen vacancy (V O-s) and Co promotes the mobility of lattice oxygen via increasing bulk oxygen vacancies (V O-b). Highlights • Co x Ce 1− x O δ catalyst shows higher activity than that of single CeO 2 and Co 3 O 4. • Strong interactions exist between Co and Ce cations via electron transfer. • Ce facilitates the creation of surface oxygen vacancy (V O-s) to ignite soot oxidation. • Co promotes the mobility of lattice oxygen via increasing bulk oxygen vacancies (V O-b). Abstract Three-dimensionally ordered macroporous (3DOM) Co x Ce 1− x O δ oxides with different Co/Ce atomic ratios were synthesized by a colloidal crystal template (CCT) method. They show higher activity for soot combustion in O 2 than single CeO 2 and Co 3 O 4 under loose contact conditions. XRD, Raman, XPS, H 2 -TPR and soot-TPR characterizations were carried out to study the surface and bulk oxygen vacancies and to correlate them to the activity. There exists electron transfer from Ce to Co in the matrix. Both Ce3+ and Co2+ species contribute importantly to the creation of surface and bulk oxygen vacancies, which determine the ignition and burnout temperatures of the catalysts, respectively. [ABSTRACT FROM AUTHOR]

Objective: A growing body of research suggests a link between varicocele and male infertility (MI). However, current evidence is mainly based on retrospective studies, which are prone to interference from confounding factors and cannot establish causal relationships. Mendelian randomization (MR) studies on the causal relationship between varicocele and MI are very limited. Therefore, this study conducted a two-sample MR study to elucidate the causal effect between the two., Methods: Download the data set GSE216907 from the GEO database, and use R software to screen differential genes in normal and varicocele tissue samples. The drug targets of Bu Shen Huo Xue Prescription (BSHXP) were derived from the Herb database. All genetic datasets were obtained using publicly available summary statistics based on individuals of European ancestry from the IEU GWAS database. MR analysis was performed using MR Egger, weighted median (WM) and inverse variance weighted (IVW) methods to assess the causal relationship between exposure and outcome and to validate the findings by comprehensively evaluating the effects of pleiotropic effects and outliers. The renal vein constriction method was used to establish a pathological model of varicocele infertility. The drug was administered continuously for 60 days and the relevant indicators of the rats were observed., Results: Obtain two therapeutic targets for varicocele through intersection analysis: MEGF9 and MLLT11, and were verified by molecular docking. MR analysis showed that MEGF9 was positively associated with MI (MR Egger, OR: 1.639, 95% CI: 1.124-2.391, P = 0.024; WM, OR: 1.235, 95% CI: 1.003-1.521, P = 0.047). MEGF9 is also positively associated with MI (IVW, OR: 1.35, 95% CI: 1.069-1.705, P = 0.012). Sensitivity analysis showed no heterogeneity and horizontal pleiotropy. The expression of MEGF9 and MLLT11 increased in the varicocele model group, while the expression decreased after treatment with low, medium, and high doses of BSHXP. In addition, the sperm number, motility, morphology, and fertility of rats in the model group were significantly lower than those in the control group ( P <0.05). After BSHXP treatment, all indicators were significantly better than those of the model group ( P <0.05)., Conclusion: In conclusion, this study indirectly supports that varicocele causes MI. BSHXP inhibiting MEGF9 and MLLT11 may become a potential therapeutic target for alleviating varicocele and MI., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Cai, Sun, Deng, Jin, Zhao, Xing, Liu and Jin.)