The hierarchical aggregation of molecular nanostructures from multiple components is a grand synthetic challenge, which requires highly selective linkage control. We demonstrate how two orthogonal ...linkage groups, that is, organotin and lanthanide cations, can be used to drive the aggregation of a giant molecular metal oxide superstructure. The title compound {(Sn(CH3)2)2O4{CeW5O18 TeW4O16CeSn(CH3)24TeW8O314}2}46− (1 a) features dimensions of ca. 2.2×2.3×3.4 nm3 and a molecular weight of ca. 25 kDa. Structural analysis shows the hierarchical aggregation from several independent subunits. Initial biomedical tests show that 1 features an inhibitory effect on the proliferation of HeLa cells based on an apoptosis pathway. In vivo experiments in mice reveal the antiproliferative activity of 1 and open new paths for further development of this new compound class.
Hierarchical assembly of a giant heterometallic polyoxotungstate supercluster with a molecular weight of ca. 25 kDa is reported. Geometrically unrestricted cerium(III) and geometrically restricted dimethyl tin cation linkers are used to gain access to a giant molecular species featuring three different polyoxometalate building units. The compound demonstrates in vitro and in vivo antiproliferative activity against HeLa cervical cancer cell lines.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Electrocatalytic water splitting into H2 and O2 is a key technology for carbon‐neutral energy. Here, we report a modular materials design leading to noble metal‐free composite electrocatalysts, which ...combine high electrical conductivity, high OER and HER reactivity and high durability. The scalable bottom‐up fabrication allows the stable deposition of mixed metal oxide nanostructures with different functionalities on copper foam electrodes. The composite catalyst shows sustained OER and HER activity in 0.1 m aqueous KOH over prolonged periods (t>10 h) at low overpotentials (OER: ≈300 mV; HER: ≈100 mV) and high faradaic efficiencies (OER: ≈100 %, HER: ≈98 %). The new synthetic concept will enable the development of multifunctional, mixed metal oxide composites as high‐performance electrocatalysts for challenging energy conversion and storage reactions.
Efficient electrochemical water splitting is achieved by hydrothermal deposition of a bifunctional mixed metal oxide electrocatalyst on copper foam electrodes. Individual metal oxide components are chosen for catalytic activity, electrical conductivity, and structural/chemical stability. The modular synthesis based on molecular precursors could lead to a new class of multifunctional catalysts for challenging energy conversion and storage reactions.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Crack assessment of bridge piers using unmanned aerial vehicles (UAVs) eliminates unsafe factors of manual inspection and provides a potential way for the maintenance of transportation ...infrastructures. However, the implementation of UAV‐based crack assessment for real bridge piers is hindered by several key issues, including the following: (a) both perspective distortion and the geometry distortion by nonflat structural surfaces usually appear on crack images taken by the UAV system from the pier surface; however, these two kinds of distortions are difficult to correct at the same time; and (b) the crack image taken by a close‐range inspection flight UAV system is partially imaged, containing only a small part of the entire surface of the pier, and thereby hinders crack localization. In this paper, a new image‐based crack assessment methodology for bridge piers using UAV and three‐dimensional (3D) scene reconstruction is proposed. First, the data acquisition of UAV‐based crack assessment is discussed, and the UAV flight path and photography strategy for bridge pier assessment are proposed. Second, image‐based crack detection and 3D reconstruction are conducted to obtain crack width feature pair sequences and 3D surface models, respectively. Third, a new method of projecting cracks onto a meshed 3D surface triangular model is proposed, which can correct both the perspective distortion and geometry distortion by nonflat structural surfaces, and realize the crack localization. Field test investigations of crack assessment of a real bridge pier using a UAV are carried out for illustration, validation, and error analysis of the proposed methodology.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
The exploration of high nuclearity molecular metal oxide clusters and their reactivity is a challenge for chemistry and materials science. Herein, we report an unprecedented giant molecular ...cerium–bismuth tungstate superstructure formed by self‐assembly from simple metal oxide precursors in aqueous solution. The compound, {W14CeIV6O61(W3Bi6CeIII3(H2O)3O14B‐α‐BiW9O333)2}34− was identified by single‐crystal X‐ray diffraction and features 104 metal centers, a relative molar mass of ca. 24 000 and is ca. 3.0×2.0×1.7 nm3 in size. The cluster anion is assembled around a central {Ce6} octahedron which is stabilized by several molecular metal oxide shells. Six trilacunary Keggin anions (B‐α‐BiW9O339−) cap the superstructure and limit its growth. In the crystal lattice, water‐filled channels with diameters of ca. 0.5 nm are observed, and electrochemical impedance spectroscopy shows pronounced proton conductivity even at low temperature.
A giant cerium–bismuth tungstate cluster featuring more than 100 metal ions and a relative molar mass of approximately 24 000 is structurally characterized. The cluster anions form a highly 3D‐porous crystalline lattice featuring water‐filled channels. Proton conductivity measurements show high proton mobility within the framework.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Novel 3D Ni1−xCoxSe2 mesoporous nanosheet networks with tunable stoichiometry are successfully synthesized on Ni foam (Ni1−xCoxSe2 MNSN/NF with x ranging from 0 to 0.35). The collective effects of ...special morphological design and electronic structure engineering enable the integrated electrocatalyst to have very high activity for hydrogen evolution reaction (HER) and excellent stability in a wide pH range. Ni0.89Co0.11Se2 MNSN/NF is revealed to exhibit an overpotential (η10) of 85 mV at −10 mA cm−2 in alkaline medium (pH 14) and η10 of 52 mV in acidic solution (pH 0), which are the best among all selenide‐based electrocatalysts reported thus far. In particular, it is shown for the first time that the catalyst can work efficiently in neutral solution (pH 7) with a record η10 of 82 mV for all noble metal‐free electrocatalysts ever reported. Based on theoretical calculations, it is further verified that the advanced all‐pH HER activity of Ni0.89Co0.11Se2 is originated from the enhanced adsorption of both H+ and H2O induced by the substitutional doping of cobalt at an optimal level. It is believed that the present work provides a valuable route for the design and synthesis of inexpensive and efficient all‐pH HER electrocatalysts.
An integrated electrocatalyst comprising 3D mesoporous Ni0.89Co0.11Se2 nanosheet networks on Ni foam is synthesized, and it demonstrates very high activities and excellent stabilities for hydrogen evolution reaction (HER) in all‐pH conditions. Theoretical calculations verify that electronic structure engineering by optimal Co doping enhances the adsorption of H+ and H2O, leading to the advanced all‐pH HER activity of the catalyst.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Upon heating, polyesters decompose to small molecules and release flammable volatiles and toxic gases, primarily through chain scission of their ester linkages, and therefore exhibit poor fire‐safety ...properties, thus restricting their applications. Reported herein is an end‐group‐capturing effect of (bis)oxazoline groups, generated from the thermal rearrangement of the N‐(2‐hydroxyphenyl)phthalimide (HPI) moiety which was incorporated into the polyester chain by copolymerization. These copolyesters, as a result, exhibit high efficiency in retarding decomposition by capturing the decomposed products, particularly for the carbonyl‐terminated fragments, thus increasing the fire‐safety properties, such as self‐extinguishing, anti‐dripping, and inhibiting heat release and smoke production. The successful application of this method in both semi‐aromatic and aliphatic polyesters provide promising perspectives to designing versatile fire‐safe polymers.
Captured: End‐group capture of benzoxazole from the thermal rearrangement of a hydroxy‐containing phthalimide group contributes to the fire‐safety features of polyesters. This novel strategy exhibits applicability and efficiency for both semi‐aromatic and aliphatic polyesters, providing a new design approach to fire‐safe polymers.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
This roadmap demonstrates a series of two-dimensional nanomaterials, such as graphene, black phosphorus, oxides, layered double hydroxides, chalcogenides, bismuth-based layered compounds, MXenes, ...metal organic frameworks, covalent organic frameworks, and others, for environmental catalysis.
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Environmental catalysis has drawn a great deal of attention due to its clean ways to produce useful chemicals or carry out some chemical processes. Photocatalysis and electrocatalysis play important roles in these fields. They can decompose and remove organic pollutants from the aqueous environment, and prepare some fine chemicals. Moreover, they also can carry out some important reactions, such as O2 reduction reaction (ORR), O2 evolution reaction (OER), H2 evolution reaction (HER), CO2 reduction reaction (CO2RR), and N2 fixation (NRR). For catalytic reactions, it is the key to develop high-performance catalysts to meet the demand for targeted reactions. In recent years, two-dimensional (2D) materials have attracted great interest in environmental catalysis due to their unique layered structures, which offer us to make use of their electronic and structural characteristics. Great progress has been made so far, including graphene, black phosphorus, oxides, layered double hydroxides (LDHs), chalcogenides, bismuth-based layered compounds, MXenes, metal organic frameworks (MOFs), covalent organic frameworks (COFs), and others. This content drives us to invite many famous groups in these fields to write the roadmap on two-dimensional nanomaterials for environmental catalysis. We hope that this roadmap can give the useful guidance to researchers in future researches, and provide the research directions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Breast cancer is now the most frequently diagnosed malignancy, and metastasis remains the leading cause of death in breast cancer. However, little is known about the dynamic changes during the ...evolvement of dissemination. In this study, 65 968 cells from four patients with breast cancer and paired metastatic axillary lymph nodes are profiled using single‐cell RNA sequencing (scRNA‐seq) and spatial transcriptomics. A disseminated cancer cell cluster with high levels of oxidative phosphorylation (OXPHOS), including the upregulation of cytochrome C oxidase subunit 6C and dehydrogenase/reductase 2, is identified. The transition between glycolysis and OXPHOS when dissemination initiates is noticed. Furthermore, this distinct cell cluster is distributed along the tumor's leading edge. The findings here are verified in three different cohorts of breast cancer patients and an external scRNA‐seq dataset, which includes eight patients with breast cancer and paired metastatic axillary lymph nodes. This work describes the dynamic metabolic evolvement of early disseminated breast cancer and reveals a switch between glycolysis and OXPHOS in breast cancer cells as the early event during lymph node metastasis.
By single‐cell RNA sequencing and spatial transcriptomics, the early early‐disseminated breast cancer cells are found to travel from the border of primary tumor to axillary lymph nodes. During this metastasis, a switch between glycolysis and oxidative phosphorylation occurs in early disseminated breast cancer cells, indicating an interesting dynamic metabolic evolvement.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Diabetes is a disorder of glucose metabolism, and over 90% are type 2 diabetes. Diabetic cardiomyopathy (DCM) is one of the type 2 diabetes complications, usually accompanied by changes in myocardial ...structure and function, together with cardiomyocyte apoptosis. Our study investigated the effect of curcumin on regulating oxidative stress (OS) and apoptosis in DCM. In vivo, diabetes was induced in an experimental rat model by streptozoticin (STZ) together with high‐glucose and high‐fat (HG/HF) diet feeding. In vitro, H9c2 cardiomyocytes were cultured with high‐glucose and saturated free fatty acid palmitate. Curcumin was orally or directly administered to rats or cells, respectively. Streptozoticin ‐induced diabetic rats showed metabolism abnormalities and elevated markers of OS (superoxide dismutase SOD, malondialdehyde MDA, gp91phox, Cyt‐Cyto C), enhanced cell apoptosis (Bax/Bcl‐2, Cleaved caspase‐3, TUNEL‐positive cells), together with reduced Akt phosphorylation and increased Foxo1 acetylation. Curcumin attenuated the myocardial dysfunction, OS and apoptosis in the heart of diabetic rats. Curcumin treatment also enhanced phosphorylation of Akt and inhibited acetylation of Foxo1. These results strongly suggest that apoptosis was increased in the heart of diabetic rats, and curcumin played a role in diabetic cardiomyopathy treatment by modulating the Sirt1‐Foxo1 and PI3K‐Akt pathways.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Virgin microplastics undergo aging and form oxygen-containing functional groups when they enter the environment. Therefore, the sorption of organic pollutants onto microplastics is not limited to ...hydrophobic organic pollutants and can also occur with hydrophilic organic pollutants. Therefore, understanding the sorption behaviors and mechanism between aged microplastics and hydrophilic organic pollutants is essential for evaluating the real effects of microplastics in the environment. We investigated the impacts of the UV-accelerated aging of polystyrene (PS) and polyvinylchloride (PVC) on their sorption interactions with ciprofloxacin (CIP). The results of infrared spectroscopy (IR) and scanning electron microscopy (SEM) showed significant surface oxidation and localized microcracks on the aged microplastics. The sorption kinetics and isotherms models indicated that the sorption capacity of aged microplastics is higher than that of pristine microplastics, and their physical interactions, including partitioning, electrostatic interactions, and intermolecular hydrogen bonding, were the dominant mechanism, as demonstrated by FTIR analysis. Moreover, the sorption capacity of the pristine microplastics decreased as the degree of crystallinity increased, whereas the opposite trend was observed with aged microplastics, which means that the crystallinity is not the controlling factor. In addition, salinity suppressed adsorption on all the tested microplastics. The pH influences the electrostatic attraction between the microplastics and CIP because CIP has a different charge at different pH values. The results presented herein confirm the importance of studying the adsorption between hydrophilic organic pollutants and aged microplastics because ultimately, all microplastics become aged. Moreover, the effects of aged microplastics with adsorbed hydrophilic chemicals on organisms need to be further studied.
Display omitted The sorption behaviors and mechanism between aged microplastics and hydrophilic organic pollutants is discussed for evaluating the real effects of microplastics in the environment.
•More oxygen-containing functional groups were found on aging microplastics.•Aged microplastics have high sorption capacity for hydrophobic organic pollutants.•Increasing NaCl concentration decreased the adsorption of HOP on microplastics.•Adsorption mechanism were proposed for CIP adsorption on aged microplastics.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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