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Abstract Electrochemical reduction of CO2 to syngas (CO and H2) offers an efficient way to mitigate carbon emissions and store intermittent renewable energy in chemicals. Herein, the hierarchical one‐dimensional/three‐dimensional nitrogen‐doped porous carbon (1D/3D NPC) is prepared by carbonizing the composite of Zn‐MOF‐74 crystals in situ grown on a commercial melamine sponge (MS), for electrochemical CO2 reduction reaction (CO2RR). The 1D/3D NPC exhibits a high CO/H2 ratio (5.06) and CO yield (31 mmol g−1 h−1) at −0.55 V, which are 13.7 times and 21.4 times those of 1D porous carbon (derived from Zn‐MOF‐74) and N‐doped carbon (carbonized by MS), respectively. This is attributed to the unique spatial environment of 1D/3D NPC, which increases the adsorption capacity of CO2 and promotes electron transfer from the 3D N‐doped carbon framework to 1D carbon, improving the reaction kinetics of CO2RR. Experimental results and charge density difference plots indicate that the active site of CO2RR is the positively charged carbon atom adjacent to graphitic N on 1D carbon and the active site of HER is the pyridinic N on 1D carbon. The presence of pyridinic N and pyrrolic N reduces the number of electron transfer, decreasing the reaction kinetics and the activity of CO2RR. The CO/H2 ratio is related to the distribution of N species and the specific surface area, which are determined by the degree of spatial confinement effect. The CO/H2 ratios can be regulated by adjusting the carbonization temperature to adjust the degree of spatial confinement effect. Given the low cost of feedstock and easy strategy, 1D/3D NPC catalysts have great potential for industrial application.

Red phosphorus has been well-recognized as promising anode materials for lithium-ion batteries (LIBs) and potassium-ion batteries (PIBs) due to its extremely high theoretical capacity and low cost. However, the huge volume change and poor electric conductivity severely limit its further practical application. Herein, the nanoscale ultrafine red phosphorus has been successfully confined in a three-dimensional pitch-based porous carbon skeleton composed of well-interconnected carbon nanosheets through the vaporization-condensation method. Except for the traditional requirement of high electric conductivity and stable mechanical stability, the micropores and small mesopores in the porous carbon matrix centered at 1 to 3 nm and the abundant amount of oxygen-containing functional groups are also beneficial for the high loading and dispersion of red phosphorus. As anode for LIBs, the composite exhibits high reversible discharge capacities of 968 mAh g−1, excellent rate capabilities of 593 mAh g−1 at 2 A g−1, and long cycle performance of 557 mAh g−1 at 2 A g−1. More impressively, as the anode for PIBs, the composite presents a high reversible capacity of 661 mAh g−1 and a stable capacity of 312 mAh g−1 at 0.5 A g−1 for 500 cycles with a capacity retention up to 84.3%. This work not only sheds light on the structure design of carbon hosts with specific pore structure but also open an avenue for high value-added utilization of coal tar pitch.

Highlights Recent advances in the metal–organic framework (MOF)-related catalysts for electrochemical ammonia synthesis protocols under ambient reaction conditions are summarized and discussed. The design and fabrication of efficient electrocatalysts from MOF for the reduction of N2 and NO3 − are systematically analyzed. Based on the current advances, the ongoing challenges and promising perspectives are highlighted.

In the viewpoint of ammonia economy, electrochemical N2 reduction reaction (NRR) under mild condition is a very promising approach for sustainable development. By virtue of robust activity and low cost, transition-metal-based materials become one kind of the most attractive electrocatalysts in realizing ammonia synthesis to the industrial level. However, the investigation related to NRR electrocatalysts still mainly rely on costly substance or fabrication process, which greatly restrict their large-scale applications. In this work, a simple fabricated FeS2 electrode is adopted as NRR catalysts. The abundant surface defects due to the existence of Cr element, as well as the synergistic effect between FeS2 crystal planes provided excellent electrocatalytic performance with a high NH3 yield rate (11.5 μg h−1mg -1 Fe) and Faradaic efficiency (14.6%) at -0.2 V vs. reversible hydrogen electrode (RHE) toward NRR under ambient conditions. The superior catalytic performance of such non-precious metal catalysts would strongly promote the application of NRR process industrially.

Abstract Electrocatalytic nitrogen reduction reaction is a carbon-free and energy-saving strategy for efficient synthesis of ammonia under ambient conditions. Here, we report the synthesis of nanosized Bi2O3 particles grown on functionalized exfoliated graphene (Bi2O3/FEG) via a facile electrochemical deposition method. The obtained free-standing Bi2O3/FEG achieves a high Faradaic efficiency of 11.2% and a large NH3 yield of 4.21 ± 0.14 $$ \upmu{\text{g}}_{{{\text{NH}}_{3} }} $$ μ g NH 3 h−1 cm−2 at − 0.5 V versus reversible hydrogen electrode in 0.1 M Na2SO4, better than that in the strong acidic and basic media. Benefiting from its strong interaction of Bi 6p band with the N 2p orbitals, binder-free characteristic, and facile electron transfer, Bi2O3/FEG achieves superior catalytic performance and excellent long-term stability as compared with most of the previous reported catalysts. This study is significant to design low-cost, high-efficient Bi-based electrocatalysts for electrochemical ammonia synthesis.

Background: Hypertrophy of the ligamentum flavum (HLF) is a common contributor to spinal stenosis which results in significant neurological impairments. Circular RNA (circRNA) circ_0003609 has been linked to HLF; however, the exact mechanism by which it causes this disease is unclear. Methods: Circ_0003609 expressions were regulated in HLF cells by overexpression vectors and RNA interference. Cell proliferation and fibrosis-related gene expression were checked by the Cell Counting Kit-8 (CCK-8) assay and western blotting. CircBank's prediction of the association between miR-155 and circ_0003609 was supported by a dual-luciferase reporter experiment. The function of the miR-155/sirtuin 1 (SIRT1) axis in controlling HLF fibrosis was further examined. Results: Overexpression of circ_0003609 suppressed HLF cell propagation and fibrosis compared to its silencing. It was found that circ_0003609 served as the sponge for miR-155 and that the circ_0003609/miR-155 axis controlled the fibrosis of HLF cells. It was found that circ_0003609 acted as a sponge for miR-155, regulating the fibrosis of HLF cells. Further, miR-155 targets SIRT1, and the miR-155/SIRT1 axis promotes HLF cell fibrosis. Conclusion: Circ_0003609 ameliorates hypertrophied ligamentum flavum (LF) by modulating the miR-155/SIRT1 axis, indicating a potential treatment approach for HLF. [ABSTRACT FROM AUTHOR]

Rhodium-catalyzed C-H allylation of acrylamides with allyl acetates is reported. The use of weakly coordinating directing group resulted in high reaction efficiency, broad functionality tolerance and excellent γ-selectivity, which opens a new synthetic pathway for the access of 1,4-diene skeletons. [ABSTRACT FROM AUTHOR]

Rh(III)-catalyzed C--H olefinic alkynylation of enamides for the stereospecific construction of synthetically useful Z-type enynamides is reported. This protocol displays good functionality tolerance and operational simplicity thus providing an alternative synthetic opportunity for the ease of access to specific 1,3-enyne derivatives. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the study was to investigate the role of the intra-operative three-dimensional imaging in the tibial plateau fractures with complex depressions. Material and methods: Thirty tibial plateau fracture patients with complex depression were treated with the use of intra-operative three-dimensional imaging (Arcadis 3D). The image quality as well as the clinical benefit was evaluated. Results: In total 74 plates were used in these 30 patients. Six Kirschner wires and 50 screws were used outside the plate as raft technique in 4 and 21 patients. The additional critical imaging information which was unachievable in plain fluoroscopy was gain in 12 patients. Four patients among these 12 patients were revised because of the depression. Two patients were revised due to the misplacement of screws. Conclusion: The intra-operative three-dimensional imaging (Arcadis) is necessary when the two-dimensional fluoroscopy was unsatisfactory in the depressed tibial plateau fracture. [ABSTRACT FROM AUTHOR]

The article discusses the progress and problems encountered by China in its curriculum reform of basic education. The implementation of a new curriculum in the country has affected the administrative style of its government, increased the ratios of local and school curriculums and developed innovative approaches in teacher development. Problems such as the lack of flexibility of the curriculum standards, an increase in teacher workloads, and the cultural dilemmas of school leaders are experienced.

Investigates the novel tandem cyclization or ring formation reaction with electrophiles of alpha-aminoalkyl radicals. Novel reaction sequence comprising site specific formation of an alpha-aminoalkyl radical; Regioselective addition of the radical to an unactivated double bond; Reduction of the radical to a carbanion; Carbanion trapping by an electrophile.

Reports on the development of 1,2,4-triazole-stabilized allenic anions for the syntheses of alpha,beta-unsaturated esters, gamma-lactones and 1,2,3,5-tetrasubstituted pyrroles. Features of benzotriazole-stabilized carbanions; Uses of allenes; Significance of the methods in organic synthesis.

Describes the advantageous use of benzotriazole-stabilized allylic anion for the syntheses of functionalized alpha,beta-unsaturated ketones, gamma-lactones, gamma-lactams and beta-substituted esters. Development of 1,2,4-triazole-stabilized allylic anions; Factors affecting the synthetic utility of allylic anions.