PtFeCo alloy nanostructures in a TriStar shape with tunable Fe and Co content are developed for the electrocatalytic hydrogen evolution reaction (HER). With electronic and surface structures well-tailored, the PtFeCo nanostructures exhibit dramatically enhanced performance in HER against commercial Pt/C and other Pt-based nanoparticles.

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Designing highly active Keggin-anion anchored on pz-based frameworks is desirable but still a huge challenge. Herein, three new POM-based inorganic–organic hybrid compounds [{Ag5(pz)7}­(BW12O40)] (1), [{Ag5(pz)7}­(SiW12O40)]­(OH)·H2O (2), (Hpyr)­[{Ag­(pz)}2(PMo12O40)] (3) (pz = pyrazine, pyr = pyrrole) have been fabricated via a hydrothermal synthesis method. All compounds were characterized by elemental analyses, infrared spectroscopy (IR), powder X-ray diffraction (PXRD), thermogravimetric (TG), scanning electron micrographs (SEM), and transmission electron microscope (TEM). Single-crystal X-ray diffraction displays that the configurations of compounds 1 and 2 are parallel. In compound 1, the [BW12O40]5– is as 8-connected node incorporated into the orifice of the Ag-pz framework forming the glamorous POM-based metal organic frameworks (POMOFs). And the 3D POMOFs possess a kind of novel topology {42·54}2{44·512·68·73·9}­{44·53·63}­{44·55·6·74·9}­{73}. There is a metal–organic nanotube structure constructed by four Ag-pz chains in compound 3. Then, the opened POMOFs consist of [PMo12O40]3– clusters encircled in metal–organic nanotubes with the topology {34·46·54·6}2­{34·48·58·64·74}. When used as electrode materials, as-prepared compounds 1, 2, and 3 have high specific capacitance of 1058, 986, and 1611 F g–1 at a current density of 2.16A g–1 and favorable cycling stability; after 1000 cycles, the retention rates of the capacitance are 90.3%, 94.5%, and 84.8% at 15.12 A g–1 in supercapacitors, respectively. Moreover, the ability of compounds 1–3 to degrade dyes is excellent under UV irradiation. The degradation rates of RhB are 94.89% for 1, 93.06% for 2, and 96.88% for 3 after 150 min, and the degradation rates of MB are 96.48% for 1, 94.28% for 2, and 98.58% for 3 after 90 min. These results illustrate that compounds 1–3 have potential applications in energy functional materials and organic pollutant degradation.

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Scopolia tangutica is a traditional Chinese medicine used for antispasmodic, anesthesia, analgesia, and sedation. Its medicinal activity is associated to alkaloid constituents, including tropane and cinnamamide types. Low content of alkaloids in plant makes them difficult to be isolated and identified. The present work developed an effective method to quickly characterize alkaloids from Scopolia tangutica by high‐performance liquid chromatography coupled with quadrupole time‐of‐flight tandem mass spectrometry. Thirteen reference compounds were studied for their fragmentation pathways, including five tropane alkaloids and eight cinnamamide ones. Alkaloid constituent was analyzed by an optimized high‐performance liquid chromatography method and mass spectrometry analysis to achieve systematic characterization of alkaloids from Scopolia tangutica. As a result, 53 compounds were identified, including 21 tropane alkaloids (eight new ones), 18 caffeoyl ones (ten new ones) and 14 dicaffeoyl ones (seven new ones). It was important to provide rich information in phytochemical study and structure‐guided isolation of important compounds from this plant.

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A simple and sensitive HPLC method with fluorescence detection (HPLC-FLD) is reported for the simultaneous determination of metabolites of four nitrofuran drugs (furazolidone, furaltadone, nitrofurantoin and nitrofurazone) in pork muscle. The method involves acid hydrolysis of the protein-bound drug metabolites and the conjugation of the released side-chains with a novel fluorescence agent 2-hydroxy-1-naphthaldehyde. After liquid-liquid extraction and effective separation of the derivatives on a YMC-Pack Polymer C18 column at 40°C under alkaline conditions, the high fluorescence intensity of these derivatives at emission wavelength λem = 463 nm enables their simultaneous determination in pork muscle at concentrations as low as 1 µg kg⁻¹. The method was validated using blank pork muscle fortified with all four metabolites at 0.5, 1.0 and 2.0 µg kg⁻¹. Recoveries were > 92.3% with RSDs < 8.5% for all four metabolites. The results obtained with HPLC-FLD and LC-MS/MS methods showed very good agreement for pork muscle samples.