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The first enantioselective dearomative [3+2] annulation of 5-amino-isoxazoles with quinone monoimines was realized using a chiral phosphoric acid as catalyst. Various novel (bridged) isoxazoline fused dihydrobenzofurans bearing two continuous quaternary stereocenters were achieved in moderate to good yields (up to 94%) with moderate to good enantioselectivities (up to 98% ee). The absolute configurations of two products were assigned by X-ray crystal structural analyses and a plausible reaction mechanism was proposed. [ABSTRACT FROM AUTHOR]

Enantioselective dearomatization inverse-electron-demand Diels–Alder reaction/oxidation of indoles with 2-(2-nitrovinyl)-1,4-benzoquinone was realised using a chiral bisoxazoline/zinc complex as a catalyst. This transformation allowed for the synthesis of enantioenriched six-membered [2,3]-fused indolines (up to 99% yield and 88% ee). [ABSTRACT FROM AUTHOR]

A pronounced enthalpy release occurs around 1.38Tg in the prototypical metal–organic framework glass formed from ZIF-4 [Zn(C3H3N2)2], but there is no sign for any crystallization (i.e., long-range ordering) taking place. The enthalpy release peak is attributed to pore collapse and structural densification. [ABSTRACT FROM AUTHOR]

A new type of TiO2-B nanoribbon anchored with NiO nanosheets (TiO2@NiO) is synthesized via a hydrothermal process and a subsequent homogeneous precipitation method. XRD analysis indicates that TiO2-B and cubic NiO phases exist in the composites. According to SEM images, the morphology of the TiO2@NiO hybrid material is unique, similar to that of leaf mosaic in biological systems. According to electrochemical investigations, the nanostructured hybrid material as an anode exhibits superior initial charge/discharge capacity and capacity retentions. The initial discharge capacity of the TiO2@NiO hybrid nanostructure is 395 mA h g−1, and the capacity remains 380 mA h g−1 after 50 charge/discharge cycles, which is about 96.2% capacity retention and 7.8% higher than that of pristine TiO2-B nanoribbons. [ABSTRACT FROM AUTHOR]

A previous study has revealed that Lactiplantibacillus plantarum ( Lp. plantarum ) dy-1 fermentation changed the structural properties and in vitro fecal fermentation characteristics of barley dietary fiber. However, the health-promoting effects of fermented dietary fiber in vivo remained unclear. This study was aimed at comparing the ameliorative effects of barley dietary fiber fermented with or without Lp. plantarum dy-1 on lipid metabolism, gut microbiota composition and hepatic energy metabolism. After a twelve-week intervention, fermented barley dietary fiber (FBDF) reduced the body weight and fat accumulation in liver and epididymal white adipose tissue, improved HFD-induced hyperlipidemia and glucose intolerance, and increased short chain fatty acid (SCFA) levels, exhibiting effects that were better than those of raw barley dietary fiber (RBDF). FBDF supplementation improved the gut microbiota composition, specifically enhancing the abundance of probiotic and SCFA-producing bacteria, such as Akkermansia and Muribaculaceae , while RBDF exhibited regulatory effects on harmful bacteria ( Escherichia - Shigella and Desulfovibrionaceae ). Additionally, FBDF up-regulated the expression of genes related to energy metabolic processes, such as aerobic respiration and oxidative phosphorylation, inhibited the genes related to lipid biosynthetic metabolism, and improved the activities of hepatic energy metabolism-related enzymes, demonstrating effects that were better than those of RBDF. Therefore, this study indicated the potential of using FBDFs as healthy food resources to prevent obesity or as prebiotics to improve gut microbiota.

Flame-retardant coatings have attracted increasing attention in mitigating the fire threat of flammable polymer materials. Their durable application inevitably provides high resistance to various complex environments, however, discarded stable materials will turn into another man-made waste disaster. The paradigm shift toward a sustainable future is to combine durability and recyclability of coatings. Herein, we demonstrate a biomimetic coating that reversibly captures active flame-retardant nanomaterials by flocculation assembly using anionic polyacrylamide covering the polyurethane foam surface. Strong hydrogen bonding and microstructural interlocking provide the coating with high durability under complex harsh conditions (underwater, chemical exposure, hydrothermal aging, long-term external extrusion, etc. ). Meanwhile, the disassembly/reorganization of the coating can be easily repeated in response to pH stimulation with a recycling rate of 97%. The experiments and theoretical calculations reveal the mechanism of the reversible flocculation assembly. This biomimetic strategy of responsive flocculation assembly opens the way for functional coatings with integrated durability and recyclability.

Incorrect discharge of dye wastewater will cause environment pollution and be very harmful to human health. Visible-light photocatalysis over large-scale synthesized semiconductor materials can become one of the feasible solutions for the practical application of purifying dye wastewater. As a new candidate, carbon dots (CDs) with unique fluorescence were fabricated on a tens of grams scale and then further applied to the kilogram-scale synthesis of a CDs/TiO 2 composite by one-step heat treatment. Compared with single TiO 2 nanoparticles (NPs), the CDs/TiO 2 composite with a large specific surface area exhibits enhanced photo-degradation performance for methyl orange (MO). This phenomenon can be attributed to the loading of CDs in the TiO 2 NPs, which is conducive to broadening the light absorption spectrum and improving absorption intensity, narrowing the band gap, charge carrier trapping, up-converting properties, and charge separation. The kilogram-scale synthesis of the CDs/TiO 2 photocatalyst does not affect the morphology, structure, optical properties and photocatalytic performance of the composite, which opens up a new avenue to construct elaborate heterostructures for enhanced photocatalytic performance using visible light as the light source., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

As visible light photocatalysts, narrow bandgap semiconductors can effectively convert solar energy to chemical energy, exhibiting potential applications in alleviating energy shortage and environmental pollution. Cu 2 O hollow spheres with a narrow band gap and uniform hierarchical structures have been fabricated in a controlled way. The one-pot solvothermal method without any template is simple and facile. The morphologies, crystal structures, composition, specific surface areas, and optical and photoelectric properties of the products were analyzed by various techniques. The hollow and solid Cu 2 O spheres could be fabricated by controlling the reaction time, and a possible growth process of the Cu 2 O hollow spheres was revealed. The degradation of methyl orange (MO) was used to investigate the visible-light catalytic properties of the Cu 2 O samples. More than 90% of MO is degraded under visible light illumination of 20 min, exhibiting a quick catalytic reaction. The rate constant of the Cu 2 O hollow spheres was 2.54 times and 46.6 times larger than those of the Cu 2 O solid spheres and commercial Cu 2 O powder, respectively. The possible photocatalytic mechanism of MO was revealed over Cu 2 O hollow spheres through the detection of active species. The as-prepared Cu 2 O hollow spheres display improved visible-light catalytic activity and stability, indicating their potential application in wastewater treatment., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)