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A series of non-stoichiometric La x MnO 3 with La/Mn molar ratio x in the range of 0.80–1.2 have been prepared by a glycine combustion method and calcinated at 700 °C. The Mn-rich (x < 1) and La-rich (x > 1) catalysts presented higher and lower activity for CO and propane oxidation than the stoichiometric LaMnO 3 , respectively. The La x MnO 3 presented pure perovskite phase without La- or Mn-related phases detected even calcinated at 1000 °C. Notably, the 50% conversion temperature for CO and propane oxidation on the best La 0·84 MnO 3 were around 70 and 35 °C lower than those on the stoichiometric LaMnO 3 , whereas which on the worst La 1·15 MnO 3 were around 60 and 50 °C higher. The La 0·84 MnO 3 possessing higher activity for CO and propane oxidation was predominately attributed to more Mn4+ cations, thus achieving abundant surface Mn4+–O bridge site as redox sites and surface Mn4+ sites as Lewis acidic sites, while the La 1·15 MnO 3 owning lower activity for the reactions was primarily ascribed to less Mn4+ cations, and the lower reducibility of Mn4+ cations and surface adsorbed oxygens. [Display omitted] • Non-stoichiometric La x MnO 3 with La/Mn ratio x = 0.80–1.20 were prepared by a glycine combustion method. • The La x MnO 3 with x < 1 and x > 1 showed higher and lower activity for CO and propane oxidation than the LaMnO 3. • The La x MnO 3 presented pure perovskite phase even calcinated at 1000 °C. • The best La 0·84 MnO 3 had more Mn4+–O as redox sites and Mn4+ as Lewis acidic sites. • The worst La 1·15 MnO 3 had less Mn4+ cations, and lower reducibility of Mn4+ and surface adsorbed oxygens. [ABSTRACT FROM AUTHOR]

Age-associated decreases in follicle number and oocyte quality result in a decline in female fertility, which is associated with increased infertility. Granulosa cells play a major role in oocyte development and maturation both in vivo and in vitro. However, it is unclear whether a reduction in cryptochrome 1 (Cry1) expression contributes to granulosa cell senescence, and further exploration is needed to understand the underlying mechanisms. In this study, we investigated the role of Cry1, a core component of the molecular circadian clock, in the regulation of senescence in ovarian granulosa cells. Western blotting and qRT-PCR showed that Cry1 expression was downregulated in aged human ovarian granulosa cells and was correlated with age and anti-Müllerian hormone (AMH) levels. RNA-seq analysis suggested that ferritinophagy was increased after Cry1 knockdown in KGN cells. MDA, iron, and reactive oxygen species (ROS) assays were used to detect cellular ferritinophagy levels. Ferroptosis inhibitors, iron chelators, autophagy inhibitors, and nuclear receptor coactivator 4 (NCOA4) knockdown alleviated KGN cell senescence induced by Cry1 knockdown. Immunofluorescence, immunoprecipitation, and ubiquitination assays indicated that Cry1 affected NCOA4 ubiquitination and degradation through HERC2, thereby affecting NCOA4-mediated ferritinophagy and causing granulosa cell senescence. KL201, a Cry1 stabilizer, enhanced ovarian function in naturally aged mice by reducing ferritinophagy. Our study reveals the potential mechanisms of action of Cry1 during ovarian aging and provides new insights for the clinical treatment of age-related fertility decline. A proposed molecular model of Cry1 in regulating senescence of human granulosa cells. Cry1 depletion reduced the expression of the E3 ubiquitin ligase HERC2, which reduced the ubiquitination and degradation of NCOA4, thereby promoting ferritinophagy and inducing granulosa cell senescence. [Display omitted] • Cry1 expression is downregulated in aged human ovarian granulosa cells. • Cry1 induces KGN cell senescence through NCOA4-mediated ferritinophagy. • Cry1 affects NCOA4 ubiquitination and degradation through HERC2. • Cry1 stabilizer KL201 enhances ovarian function by reducing ferritinophagy in middle-aged mice. [ABSTRACT FROM AUTHOR]

Silicon-rich anodes are desired to leverage the energy capacity of lithium-ion batteries (LIBs) towards critical markets. We prepared new silicon-rich composite anodes with a nanofiber-in-microfiber architecture using a co-axial electrospinning setup. A polyvinyl alcohol (PVA) solution that allows high silicon content serves as the central stream, which holds silicon nanoparticles into short, branched composite nanofibers. These nanofibers were wrapped by long, ductile microfibers made of polyacrylonitrile (PAN) that is supplied in the sheath fluid. After carbonization, the received carbon/silicon composites were tested as the anode of LIBs, in which the silicon-rich nanofibers host the majority of lithium ions while their thin carbon skin originated from PVA promotes the conductivity and charge transfer. The outside PAN-derived microfibers provide needed structural support for those encapsulated silicon-rich nanofibers, making the final composites also an integrated, three-dimensional current collector. The nanofibrous morphology and the void space in between help accommodate the notorious volume expansion issues during lithiation/delithiation. The new composites were confirmed on their nanofiber-in-microfiber configuration. With a Si content of 40%, this unique fibrous anode material achieves ∼900 mAh g−1 specific capacity and ∼90% capacity retention from cycle 50 to cycle 250 by effectively balancing some major challenges associated with silicon-rich anodes. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Cr3+ lattice doping in r-TiO 2 achieved Ru/Ti 0.95 Cr 0.05 O 2 with much higher activity than Ru/r-TiO 2. • Cr3+ doping led to Ru/Ti 0.95 Cr 0.05 O 2 with higher dispersion of Ru and enhanced MSIs. • The MSIs affected adsorption states of linear-CO*. • The formaiton of Blue-shifted CO* decided the much higher activity. • Ru-CO and C-O bonds were key for CO 2 methanation on supported Ru catalysts. Understanding the correlation between metal–support interactions (MSIs) and the adsorption states of reaction intermediates is critical for developing heterogeneous catalysts. To modulate MSIs and CO adsorption states, various Ru/Ti 1-x Cr x O 2 catalysts were prepared by Cr3+ cation doping and used for CO 2 methanation compared to the rutile TiO 2 -supported Ru catalyst (Ru/r-TiO 2). The activity followed the order: Ru/Ti 0.95 Cr 0.05 O 2 > Ru/Ti 0.97 Cr 0.03 O 2 > Ru/Ti 0.87 Cr 0.13 O 2 ≫ Ru/r-TiO 2. The best Ru/Ti 0.95 Cr 0.05 O 2 catalyst possessed CO 2 turnover frequency (TOF) value at 200 °C 10.2 times higher than that on the Ru/r-TiO 2. Cr3+ doping in the lattice of r-TiO 2 support led to the Ru/Ti 0.95 Cr 0.05 O 2 with higher dispersion of Ru and enhanced MSIs. A linear-CO*-II intermediate formed on the Ru/Ti 0.95 Cr 0.05 O 2 with higher C-O vibrational frequency (2003 cm−1) than the linear-CO*-I at 1972 cm−1 on the Ru/r-TiO 2 , and the blue-shifted CO possessed higher activity for CO hydrogenation to CH 4. The higher activity of the linear-CO* were accounting for the much higher TOF value of the Ru/Ti 0.95 Cr 0.05 O 2. The strength of MSIs was proved to be highly correlated with CO adsorpton states including the balance of the strength of Ru-C and C-O bonds, which were found to be a crucial factor for the activity of supported Ru-based catalysts for CO hydrogenation. [ABSTRACT FROM AUTHOR]

• Solid crystallization of dry nanogels into mesoporous ZSM-5 at ambient pressure. • Hierarchical pore structure created by jointing nanocrystals into single zeolites. • Low temperature hydrogenation/deoxygenation of Pd/Meso-ZSM-5 catalyst. • Improved conversion and anti-coking performance in guaiacol hydrodeoxygenation. • Saturated/unsaturated product regulated by hydrodeoxygenation temperature. Mesoporous structure is important to promote mass transport and active site utilization of zeolites when used in reactions involving bulky molecules. However, their conventional hydrothermal synthesis is energy and labor intensive, requiring high-pressure operation, and lengthy heating a huge amount of alkaline liquid. We successfully synthesized new mesoporous zeolites, Meso-ZSM-5, via solid-state crystallization of dry aluminosilicate nanogels. Neighbor developing nanocrystals further joint at edges, creating connected, inter-lattice mesoscale pathway in the finished single crystalline zeolites. Palladium was further loaded on these zeolites to form a bi-functional catalyst (Pd/Meso-ZSM-5). When used in the hydrodeoxygenation (HDO) of guaiacol, a major bio-oil compound with disappointing conversion and severe coking issue over many HDO catalysts, Pd/Meso-ZSM-5 exhibits superior guaiacol conversion and product distribution when compared with those supported on conventional microporous ZSM-5 counterparts. This is attributed to the improved diffusion and accessibility of active sites inside Meso-ZSM-5 with its unique hierarchically porous structure. Ring saturated hydrocarbons are largely produced at 200 °C when hydrogenation dominates while alkaylated aromatics become major HDO products as deoxygenation becomes favorable at 250 °C. These encouraging results may ignite the wide use of these mesoporous zeolites in many other reactions in both traditional fossil fuel and emerging renewable energy fields. [ABSTRACT FROM AUTHOR]