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Unsupported non-bridged uranium-carbon double bonds have long been sought after in actinide chemistry as fundamental synthetic targets in the study of actinide-ligand multiple bonding. Here we report that, utilizing Ih(7)-C80 fullerenes as nanocontainers, a diuranium carbide cluster, U=C=U, has been encapsulated and stabilized in the form of UCU@Ih(7)-C80. This endohedral fullerene was prepared utilizing the Krätschmer-Huffman arc discharge method, and was then co-crystallized with nickel(II) octaethylporphyrin (NiII-OEP) to produce UCU@Ih(7)-C80·[NiII-OEP] as single crystals. X-ray diffraction analysis reveals a cage-stabilized, carbide-bridged, bent UCU cluster with unexpectedly short uranium-carbon distances (2.03 Å) indicative of covalent U=C double-bond character. The quantum-chemical results suggest that both U atoms in the UCU unit have formal oxidation state of +5. The structural features of UCU@Ih(7)-C80 and the covalent nature of the U(f1)=C double bonds were further affirmed through various spectroscopic and theoretical analyses.

Ecto‐mesenchymal cells of mammalian tooth germ develops from cranial neural crest cells. These cells are recognised as a promising source for tooth development and regeneration. Despite the high heterogeneity of the neural crest, the cellular landscape of in vitro cultured cranial neural crest cells (CNCCs) for odontogenesis remains unclear. In this study, we used large‐scale single‐cell RNA sequencing to analyse the cellular landscape of in vitro cultured mouse CNCCs for odontogenesis. We revealed distinct cell trajectories from primary cells to passage 5 and identified a rare Alx3+/Barx1+ sub‐population in primary CNCCs that differentiated into two odontogenic clusters characterised by the up‐regulation of Pax9/Bmp3 and Lhx6/Dmp1. We successfully induced whole tooth‐like structures containing enamel, dentin, and pulp under the mouse renal capsule using in vitro cultured cells from both cranial and trunk neural crests with induction rates of 26.7% and 22.1%, respectively. Importantly, we confirmed only cells sorted from odontogenic path can induce tooth‐like structures. Cell cycle and DNA replication genes were concomitantly upregulated in the cultured NCCs of the tooth induction groups. Our data provide valuable insights into the cell heterogeneity of in vitro cultured CNCCs and their potential as a source for tooth regeneration. [ABSTRACT FROM AUTHOR]

Gas extraction is an essential measure to reduce the amount of gas discharged by mine air and prevent gas disasters.Based on the previous research and a large number of literature research, the existing coal mine gas extraction technology is systematically sorted out, the development history of coal mine gas extraction technology and equipment in China is briefly reviewed, and the research progress and application of six typical gas extraction technologies are summarized. On the basis of summarizing and analyzing the development status and technical bottlenecks of gas extraction in China, looking forward to its future development trend, high power, high reliability, high efficiency, intelligent coal mine drilling technology and equipment and increased permeability of coal seam and gas extraction from drilling technology and the key technologies of gas extraction including accurate monitoring and intelligent control of gas extraction parameters, coordinated development of coal mine gas(CBM) and coal, evaluation of abandoned (closed) mine gas “sweet spot” resources and efficient extraction technologies are the main development directions of gas extraction technology and equipment in China’s coal mines in the future.

Modulating the coordination environment of single‐atom catalysts (SACs) is an attractive approach for maximizing the catalytic activity of single‐atom centers. Currently, the synthesis of low‐coordinated SACs is mainly confined to increasing the pyrolysis temperature (≥900 °C) to control C─N volatile fragments. Herein, a novel and universal strategy for the low‐coordinated SACs modulation is presented using transition metal (e.g., Ni, Co, Zn) ionic liquid precursors under relatively mild temperature of 600 °C, which regulates the L‐shell electronic structure and decreases nearly 50% electrophilic reactivity by ionization of 4‐position N atom, thereby orienting synthesis of the SACs with metal‐N3 centers. The Ni‐N3 SACs exhibit exceptional CO2 electroreduction performance of 99.7% CO Faraday efficiency with an ultra‐high CO partial current density of 467.55 mA·cm−2 as well as a CO production rate up to 10417.51 µmol·h−1·cm−2 in flow cell. The superior catalytic activity achieves over twofold increase compared with the Ni‐N4 SACs prepared by non‐metal ionic liquid precursors due to the lower free energy of the key intermediate *COOH and the stronger adsorption energy. [ABSTRACT FROM AUTHOR]

Bubbles, widely distributed in nature and industry, have been extensively explored as important energy carriers. Despite notable progress, how to harvest the energy inherent in small bubbles remains a significant challenge. Herein, a bubble driven triboelectric nanogenerator (BD‐TENG) that can scavenge energy directly and efficiently from bubbles is explored. The BD‐TENG can generate sustained voltages of up to −120 V when small air bubbles rise in a polytetrafluoroethylene (PTFE) tube filled with deionized water. Furthermore, the effects of the tube diameter, electrode length, and bubble volume based on the harvest activity are also investigated. As a proof of concept, it is demonstrated that the BD‐TENG can be utilized to illuminate four blue LEDs. Notably, the conclusion of this research work demonstrates an innovative roadmap for bubble energy harvesting in liquid media. [ABSTRACT FROM AUTHOR]