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We report a general chemical approach to synthesize strongly ferromagnetic rare‐earth metal (REM) based SmCo and SmFeN nanoparticles (NPs) with ultra‐large coercivity. The synthesis started with the preparation of hexagonal CoO+Sm2O3 (denoted as SmCo‐O) multipods via decomposition of Sm(acac)3 and Co(acac)3 in oleylamine. These multipods were further reduced with Ca at 850 °C to form SmCo5 NPs with sizes tunable from 50 to 200 nm. The 200 nm SmCo5 NPs were dispersed in ethanol, and magnetically aligned in polyethylene glycol (PEG) matrix, yielding a PEG‐SmCo5 NP composite with the room temperature coercivity (Hc) of 49.2 kOe, the largest Hc among all ferromagnetic NPs ever reported, and saturated magnetic moment (Ms) of 88.7 emu g−1, the highest value reported for SmCo5 NPs. The method was extended to synthesize other ferromagnetic NPs of Sm2Co17, and, for the first time, of Sm2Fe17N3 NPs with Hc over 15 kOe and Ms reaching 127.9 emu g−1. These REM based NPs are important magnetic building blocks for fabrication of high‐performance permanent magnets, flexible magnets, and printable magnetic inks for energy and sensing applications. A new chemical process is developed to prepare strongly ferromagnetic SmCo5 nanoparticles (NPs) via controlled reduction of SmCo‐O multipods. The 200 nm SmCo5 NPs embedded in polyethylene glycol are aligned magnetically and show the room temperature coercivity of 49.2 kOe. The synthetic method has also been extended to prepare ferromagnetic Sm2Co17 and Sm2Fe17N3 NPs. [ABSTRACT FROM AUTHOR]

Using nanoparticles (NPs) to catalyze multiple chemical reactions in one-pot and to achieve high-yield syntheses of functional molecules/materials is an important direction in NP chemistry, catalysis and applications. In this article, we report a nanocomposite of AgPd NPs anchored on WO2.72 nanorods (NRs) (denoted as AgPd/WO2.72) as a general catalyst for formic acid dehydrogenation and transfer hydrogenation from Ar-NO2 to Ar-NH2 that further reacts with aldehydes to form benzene-fused heterocyclic compounds. The AgPd/WO2.72 catalysis is Ag/Pd dependent and Ag48Pd52 is the most active composition for the multiple chemical reactions. The high activity of AgPd/WO2.72 arises from strong interfacial interaction between AgPd and WO2.72, resulting in AgPd lattice expansion and electron polarization from AgPd to WO2.72. The syntheses proceed in one-pot reactions among formic acid, 2-nitrophenol (or 2-nitroaniline, or 2-nitrothiophenol) and aldehydes in dioxane/water (2/1 v/v) at 80–90 °C, leading to one-pot syntheses of benzoxazoles, benzimidazoles and benzothiazoles that are key ring structures present in functional compounds for pharmaceutical, optical and polymer applications. [ABSTRACT FROM AUTHOR]

Niacin, an age-old lipid-lowering drug, acts through the hydroxycarboxylic acid receptor 2 (HCAR2), a G-protein-coupled receptor (GPCR). Yet, its use is hindered by side effects like skin flushing. To address this, specific HCAR2 agonists, like MK-6892 and GSK256073, with fewer adverse effects have been created. However, the activation mechanism of HCAR2 by niacin and these new agonists is not well understood. Here, we present three cryoelectron microscopy structures of Gi-coupled HCAR2 bound to niacin, MK-6892, and GSK256073. Our findings show that different ligands induce varying binding pockets in HCAR2, influenced by aromatic amino acid clusters (W91ECL1, H1614.59, W1885.38, H1895.39, and F1935.43) from receptors ECL1, TM4, and TM5. Additionally, conserved residues R1113.36 and Y2847.43, unique to the HCA receptor family, likely initiate activation signal propagation in HCAR2. This study provides insights into ligand recognition, receptor activation, and G protein coupling mediated by HCAR2, laying the groundwork for developing HCAR2-targeted drugs. [Display omitted] • Three structures of Gi-coupled HCAR2 bound with agonists niacin, MK-6892, and GSK256073 • Diverse ligand-binding pockets of HCAR2 induced by different ligands • Different binding modes of agonists with distinct pharmacological properties to HCAR2 • Residues R111 and Y284, unique to HCA receptors, likely initiate HCAR2 activation signals Zhu et al. reported three cryo-EM structures of Gi-coupled HCAR2 bound to niacin, MK-6892, and GSK256073. The structural data combined with functional studies and computational modeling show the mechanisms of ligand recognition, ligand selectivity, receptor activation, and G protein coupling of HCAR2. [ABSTRACT FROM AUTHOR]

Co-based catalysts are highly active for synthesizing long-chain paraffins through Fischer–Tropsch synthesis. However, their exothermic reactions can cause overheating and catalyst deactivation. To address this, thermally conductive SiC-Al 2 O 3 pellets (HeatPath™) were coated with a Co/Re/Al 2 O 3 shell, significantly boosting the CO conversion rate and the yield of C 2–4 and C 5+ hydrocarbons over a wide range of temperatures by dissipating the reaction heat. The core@shell HeatPath@Co/Re/Al 2 O 3 catalyst demonstrated high productivity (up to 19.7 g CO g cat − 1 h−1), exceptional long-term stability over 660 h time-on-stream, with high-temperature operation up to 260 °C, a low CH 4 selectivity (7.1 %) and a chain growth probability (α) > 0.8. In contrast, the irreversible deactivation of a powder Co/Re/Al 2 O 3 catalyst started at 195 °C, resulting in >60 % CH 4 selectivity and ∼100 % CO conversion due to excessive local heat. The CO conversion rate on the core@shell catalyst could be further improved by increasing the H 2 /CO ratio and temperature, with commercially viable CH 4 selectivity. [Display omitted] • core@shell SiC-Al 2 O 3 @Co-Re showed high performance in Fischer-Tropsch synthesis. • core@shell catalyst improved CO conversion rate and yield of C5 + hydrocarbons. • Heat dissipation property of SiC-Al 2 O 3 pellets enhanced Fischer-Tropsch performance. • Low CH 4 and CO 2 selectivities over a wide temperature range. • High productivity (∼19.7 g CO g cat − 1 h−1) and good stability >660 h time-on-stream. [ABSTRACT FROM AUTHOR]