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2 mW cm-2). The superior ORR catalytic performance of A-FeNC is ascribed to the increased exposure of active sites, active single-atom Fe-N-C centers, and enhancement by Fe3C nanoclusters.Three novel coordination compounds, [Cu(ca)2(Hbae)2] (1), [Cu(va)2(Hbae)2] (2) and [Cu4(va)4(bae)4]·H2O (3), have been prepared by self-assembly reactions of copper(ii) chloride (1 and 2) or tetrafluoroborate (3) and CH3OH (1 and 3) or CH3CN (2) solution of 2-benzylaminoethanol (Hbae) and cinnamic (Hca, 1) or valeric (Hva, 2 and 3) acid. Crystallographic analysis revealed that both 1 and 2 have mononuclear crystal structures, wherein the complex molecules are H-bonded forming extended supramolecular chains. The tetranuclear structure of 3 is based on the Cu4(μ3-O)4 core, wherein the metal atoms are bound together by μ3 oxygen bridges from 2-benzylaminoethanol forming an overall cubane-like configuration. The strong hydrogen bonding in 1-3 leads to the joining of the neighbouring molecules into 1D chains. Concentration-dependent ESI-MS studies disclosed the equilibria between di-, tri- and tetranuclear species in solutions of 1-3. All three compounds act as catalysts for the aerobic oxidation of o-aminophenol to the phenoxazinone chromophore (phenoxazinone synthase-like activity), with the maximum reaction rates of 4.0 × 10-7, 2.5 × 10-7 and 2.1 × 10-7 M s-1 for 1, 2 and 3, respectively, supported by the quantitative yield of the product after 24 h. The dependence of the reaction rates on catalyst concentrations is evidence of reaction orders higher than one relative to the catalyst. Kinetic and ESI-MS data allowed us to assume that the tetranuclear species, originating from 1, 2 and 3 in solution, possess considerably higher activity than the species of lower nuclearity. Mechanistic and isotopic 18O-labelling experiments suggested that o-aminophenol coordinates to CuII species with the formation of reactive intermediates, while the oxygen from 18O2 is not incorporated into the phenoxazinone chromophore.Controlling and detecting cell differentiation in human mesenchymal stem cells (hMSCs) for regenerative medicine remain challenging at present. Here, we developed multifunctional gold nanoparticles (AuNPs) to control and detect osteogenic differentiation in human mesenchymal stem cells (hMSCs) in real-time. The polyethyleneimine (PEI) capped AuNPs (Au-PEI) were synthesized first and were then conjugated with a matrix metalloproteinase 13 (MMP13)-sensitive peptide-FITC group (EGPLGVRGKG-FITC) to obtain multifunctional AuNPs (AuNP-PEI-peptide-FITC). AuNP-PEI-peptide-FITC could bind siRNA with PEI by electrostatic interactions to form the AuNP-PEI-peptide-FITC/siRNA nanocomplexes, allowing efficient siRNA delivery in hMSCs. [https://www.selleckchem.com/products/napabucasin.html Napabucasin cost] The adipogenic-related gene peroxisome proliferator-activated receptor γ (PPARγ) was targeted for silencing by the AuNP-PEI-peptide-FITC/siRNA nanocomplexes to control osteogenic differentiation in hMSCs. After demonstrating that the AuNP nanocomplexes could control cell differentiation, the versatility of this tool was illustrated by showing that it can be used as a nanoprobe for real time detection of the osteogenic differentiation of hMSCs. This was done by measuring the activity of the MMP13 enzyme (produced during osteogenic differentiation) through the recovery of FITC fluorescence. This multifunctional AuNP showed a robust new methodology for controlling cell fate and simultaneously detecting cell differentiation in real-time for hMSCs, which is promising for multiple applications in regenerative medicine.Herein, low-dimensional cobalt phosphate (Co-Pi) catalysts with variable contents of crystal water were fabricated for oxygen evolution reaction (OER). Owing to the optimized electronic structure, rich surface sites and favorable charge transport ability, Co-Pi tetrahydrate exhibits remarkable OER activity with a low overpotential, large current density and high intrinsic activity, and it is proved to be the optimal Co-Pi phase for OER.In this work, a highly porous ternary NiCoFe oxide nanomesh with two-dimensional morphology and quasi-single-crystalline (QSC) feature was synthesized via a convenient molten-salt protected pyrolysis approach, which achieves remarkable OER performance with a low overpotential, high current density, improved intrinsic activity and superior operational stability.Electrolyte salts with Mg2+ and Al3+ Lewis acidic cations demonstrate polymerization of 1,3-dioxolane. The speed and extent of the reaction depends on coordination of the anion with the Mg2+ cation catalyst. Weakly coordinating anions such as TFSI- aid faster polymerization while strongly coordinating anions such as ClO4- hinder the polymerization.The oxidative coupling of secondary aldehydes and sulfinate salts is achieved using copper catalysis to form α-sulfonyl aldehydes. The use of an acidic co-solvent is important to adjust the oxidation potential of MnO2 as an oxidant. A broad range of sulfonylated aldehydes is prepared, and their further functionalisation is demonstrated. A dual ionic/radical pathway mechanism is proposed.Reaction of (CpiPr4)2UI with NaN3 resulted in formation of tetrameric uranium(iii) azide-bridged 'molecular square' [(CpiPr4)2U(μ-η1η1-N3)]4 (1). Addition of B(C6F5)3 to 1 induced loss of N2 at room temperature, yielding the uranium(v) borane-capped nitrido (CpiPr4)2U(μ-N)B(C6F5)3 (2).Many highly active electrocatalysts for the reduction of N2 to NH3 (NRR) have been synthesized but suffer from poor selectivity. One crucial reason is that the adsorption of hydrogen often dominates at the active centers at applied voltage, which leads to the competitive hydrogen evolution reaction. This work used density functional theory (DFT) calculations to develop a class of stable polyoxometalate-based electrocatalysts including phosphomolybdic-, phosphotungstic-, silicotungstic-, and silicomolybdic-acid supported Ru single atoms to efficiently catalyze the NRR process with an overpotential lower than 0.25 V. More importantly, phosphomolybdic- and phosphotungstic acid-supported Ru electrocatalysts can achieve high selectivity at applied voltage. This work offers useful insights into designing high-performance polyoxometalate-based electrocatalysts for the NRR.Noble gas (Ng) containing molecular anions are much scarcer than Ng containing cations. No neon containing anion has been reported so far. Here, the experimental observation of the molecular anion [B12(CN)11Ne]- and a theoretical analysis of the boron-neon bond is reported.The spectral mismatch between the distribution of sunlight (AM1.5G) and crystalline silicon (c-Si) solar cells is one of the most important limiting factors of the conversion efficiency of photovoltaic (PV) devices. As an effective solution, the use of the luminescence down-shifting (LDS) technique is an important way to improve the short-wavelength response of a solar cell by shifting high-energy photons to the visible range. Herein, a large-area (17 × 17 cm2) luminescent thin film consisting of a ternary europium (Eu3+) complex and polyvinyl alcohol (PVA) was successfully constructed through a solution casting method and further developed as an effective LDS layer to improve the photoelectric conversion efficiency of c-Si solar cells with a large active area (235 cm2). The self-standing LDS layer is flexible, transparent and easily attachable to the surface of the solar cell module. Compared with the uncoated c-Si solar cell, the one coated with the LDS layer displayed an enhancement of ∼15% in external quantum efficiency (EQE) due to the high luminescence quantum yield of the Eu3+ complex doped inside the layer. These results demonstrate that use of a large area luminescent film embedding an Eu3+ complex is a versatile and effective strategy to improve the conversion efficiency of large size PV devices, giving rise to its great potential application as an LDS material.Hawthorn including many plants from the genus Crataegus (C.) is used for traditional medicines, herbal drugs, and dietary supplements all over the world. In China, C. pinnatifida Bge. var. major N, E. Br, and C. pinnatifida Bge. are two major species that are used as hawthorn. The purpose of this study is to assay the myocardial protection of hawthorn fruit processed with honey (MSZ) and screen the chemical basis of MSZ on this effect. Firstly, ultra-performance liquid chromatography-quadrupole time of flight-mass spectrometry (UPLC/Q-TOF-MS) was used to analyze the chemical constituents of the sliced dry fruit of hawthorn (SZ) and MSZ. Principal component analysis (PCA) was used to differentiate them. Orthogonal partial least squares-discriminate analysis (OPLS-DA) was applied to screen different compounds between SZ and MSZ, and 32 different compounds were selected. Then a pharmacodynamic test to investigate their protective effect against myocardial ischaemia was carried out. The results demonstrated that the protective effect of MSZ was better than that of SZ on the same dose. Finally, the chemical basis for the protective effect provided by MSZ against myocardial ischaemia was speculated based on correlation analysis. Taken together, all these results suggest that phenylpropanoids, organic acids, tannins, and flavonoids might be the chemical basis of MSZ protecting against myocardial ischaemia.Much attention has been paid to the fabrication of two-dimensional (2D) nanomaterials as therapeutics for nanomedicine in recent years owing to their special physicochemical characteristics. These fascinating physicochemical properties alongside their diverse biomedical applications drive us to give a review of the present endeavors of interest in these 2D nanomaterials. In this review, the up-to-date research advances of the preparation, biocompatibility and biodegradation behaviors of 2D nanomaterials including transition-metal dichalcogenides (TMDs), transition metal oxides (TMOs), black phosphorus (BP) nanosheets, metal-organic frameworks (MOFs), 2D boron (B), boron nitride (BN), layered double hydroxides (LDHs), 2D nanoscale metals, and other kinds of 2D nanomaterials are introduced. The in vitro and in vivo bio-compatibility, including their degradation assessments from the aspects of a redox reaction, enzymes, pH, and the cell environment, etc., of the above categories of 2D nanomaterials are discussed in detail. Finally, the prospects and challenges of the development of 2D nanomaterials aiming for biomedical applications are summarized.A novel method has been established for the construction of C-S bonds using redox-active esters with disulfides in the presence of Ru-photoredox catalyst. This method exhibits remarkable functional group tolerance across a wide scope of substrates. Under mild conditions, a structurally diverse array of aryl alkyl sulfides is successfully and efficiently obtained through decarboxylative cross-coupling.Photooxidation provides a promising strategy for photocatalysis, photodynamic therapy, and environmental protection. Unfortunately, most organic photosensitizers possess weak hydrophilicity and a π-π conjugated structure, leading to singlet oxygen self-quenching, poor loadability and therefore unsatisfactory photooxidation efficiency. Thus, dispersion of these photosensitizers within a two-dimensional porous covalent organic framework has become a feasible strategy to hinder their self-aggregation and augment their loading capacity. Here, we report a phthalocyanine-based photosensitizer loaded on covalent organic framework nanosheets. This nano-photosensitizer exhibits highly dispersed organic fluorescent phthalocyanines and a high loading capacity. The fabricated nanosheets restrict self-aggregation of photosensitizer molecules and enhance the photooxidation activity, which may offer a new paradigm for photooxidation and its multiple applications.