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Oxygen reduction reaction (ORR) plays a crucial role in electrochemical energy conversion and storage devices such as metal–air batteries and water electrolyzers.

Postoperative cognitive dysfunction (POCD) is associated with worsened prognosis especially in aged population. Clinical and animal studies suggested that electroacupuncture (EA) could improve POCD. However, the underlying mechanisms especially EA's regulatory role of inflammasomes remain unclear.The model of POCD was established by partial hepatectomy surgery in 18-month mice with or without postoperative EA treatment to the Baihui acupoint (GV20) for 7 days. Cognitive functions were assessed by Morris water maze test, and proinflammatory cytokines IL-1β and IL-6 and microglia activity were assayed by qPCR, ELISA, or immunohistochemistry. Tight junction proteins, NLRP3 inflammasome and downstream proteins, and NF-κB pathway proteins were evaluated by western blotting.EA markedly preserved cognitive dysfunctions in POCD mice, associated with the inhibition of neuroinflammation as evidenced by reduced microglial activation and decreased IL-1β and IL-6 levels in brain tissue. EA also preserved hippocampal neurons and tight junction proteins ZO-1 and claudin 5. Mechanistically, the activation of NLRP3 inflammasome and NF-κB was inhibited by EA, while NLRP3 activation abolished EA's treatment effects on cognitive function.EA alleviates POCD-mediated cognitive dysfunction associated with ameliorated neuroinflammation. Mechanistically, EA's treatment effects are dependent on NLRP3 inhibition.

Optimizing the properties of carbon electrodes remains a critical challenge in the development of high-efficiency vanadium redox flow batteries. In this work, we correlate the battery performance with microstructures and surface chemistries through the controllable fabrication of perforated carbon platelets derived from metal–organic frameworks. With Raman and X-ray photoelectron spectroscopy analyses, we identify topological carbon defects and nitrogen-dopants as active sites for the oxidation of VO2+, as corroborated by the density functional theory. The optimal PCP electrode rich in these structural features is fabricated at a carbonization temperature of 800 °C to provide high electrical conductivity and a large surface area. It delivers energy efficiencies of 82.0 and 69.7% at current densities of 200 and 400 mA cm−2, respectively in a VRFB, along with high cycling stability. Further dissection of the polarization resistance confirms the catalytic activity as the underlying reason for the outstanding performance.

Developing materials with tailorable properties has been the long-sought goal of humankind. Forming composite materials with superior properties by combining two or more materials has emerged as a competitive means in the search and design of new materials. However, it is still a grand challenge to use metallic materials as a binder for composites because of their lack of adhesion. In the present work, we proposed a facile and flexible route to synthesize composites using metallic glass as a glue to bond various materials, ranging from conductors to insulators, and metals to nonmetals, together. The mechanical, magnetic and electrical performances of the composites can be manually regulated by changing the addition ratios of the metallic glass glue and the corresponding admixture. In addition, porous structures were also obtained and tuned by dissolving the soluble admixture in water. In principle, our approach provides a new idea for the fabrication and optimization of composites using metallic materials as binders. The outcome of our current research opens up a window not only to synthesize composite materials with tailorable properties universally and flexibly, but also towards the discovery of potential multi-functional metal containing composites.

Reactions of OsCl2(PPh3)3 with o-ethynylphenyl-carbonyl compounds o-HC≡CC6H4C(O)R (2, R = H (a) and Et (b)) produced the η3-o-ethynylphenyl-carbonyl complexes OsCl2(PPh3)2{η3-(o-HC≡CC6H4C(O)R)} (3)...

We lay out the design principles of Cr complexes to address issues of slow kinetics and parasitic reactions in the Fe-Cr redox flow battery (ICRFB). We identify theoretically and experimentally dipicolinic acid as a promising ligand, and synthesize its derivative to improve the solubility of the Cr complex to 0.7 M. We couple it with ferrocyanide for a neutral ICRFB delivering 120 stable cycles.

Objective Sepsis is a major challenge in intensive care unit (ICU) worldwide and the septic survivors are left with long-term cognitive deficits. This work aims to explore the effects of electroacupuncture (EA) on long-term cognitive function and its underlying mechanism in sepsis-survivor mice. Methods Sepsis was induced by cecal ligation and puncture in C57BL/6 male mice. Seven days post-surgery, sepsis-survivor mice were treated with EA or nonacupoint EA for 17 days twice daily. Then, cognitive function was evaluated by Morris water maze task. The hippocampus tissue were collected from the mice at 30 days post-surgery. The level of nitric oxide and the expression of endothelial nitric oxide (eNOS), phospho-eNOS (p-eNOS), and amyloid β–peptide (Aβ) were measured. Results Compared with the sham-operated control, sepsis-survivors had significant cognitive deficits evidenced by the increased time of escape latency and reduced crossing number in Morris water maze task, as well as lower NO and p-eNOS level and higher Aβ level. EA treatment at GV20 and ST36 acupoints but not at a nonacupoint improved the cognitive function, increased the NO and p-eNOS level, and decreased Aβ generation; while eNOS inhibitor (L-NAME) undermined the efficacy of EA treatment. Conclusion In conclusion, repeated EA treatment could ameliorate the long-term cognitive impairment via manipulating the expression of p-eNOS and related Aβ in sepsis-survivor mice.

Platinum vinylcarbene complexes are potentially useful for organometallic synthesis and catalysis, but have been rarely studied. This work reports a convenient route to make platinum vinylcarbene complexes. Treatment of [PtCl2(PPh3)]2 with propargyl alcohols HC≡CC(OH)RR’ (RR’ = Ph2, cyclo-C6H10(OH), (iPr)(C≡CTMS) and (H)(Ph)) in the presence of EtOH produced the vinylcarbene complexes trans-PtCl2{ = C(OEt)-CH=CRR’}(PPh3). Under similar condition, [PtCl2(PPh3)]2 reacted with HC≡CC(OH)Me2 to give cis-PtCl2{ = C(OEt)-CH=CMe2}(PPh3). Complex trans-PtCl2{ = C(OEt)-CH=CPh2}(PPh3) readily undergo a metathesis reaction with NaI to give trans-PtI2{ = C(OEt)-CH=CPh2}(PPh3) which can isomerize to cis-PtI2{ = C(OEt)-CH=CPh2}(PPh3). Complex trans-PtCl2{ = C(OEt)-CH=CPh2}(PPh3) reacted with PPh3 to give EtCl and the acyl complex trans-PtCl{C(O)CH=CPh2}(PPh3)2, which can undergo a decarbonylation reaction to give PtCl(CH=CPh2)(PPh3)2.

Ultra-precision machining and forming of metallic materials is of great significance in the fields of catalysts, sensors, and biomedical devices. In present work, the multi-scale cold embossing of CoCrFeNiMn high entropy alloy (HEA) with structures ranging from macro-scale to nano-scale was investigated at room temperature. In less 7 s, the macro patterns, the shapes of Arabic numerals, 5 μm wide gratings, 30 μm diameter hemispherical arrays, and ∼270 nm nanowires were formed rapidly. The highest replication of the HEA cold embossing was up to 98%. A series of slip bands were detected in the cold embossed HEA structures, which can accommodate more dislocations and facilitate the plastic deformation process. Moreover, dislocation pile-up and large angular rotation within grains are observed in the deformation areas, which is favorable to contain dislocation cells, leading to grain refinement and an increase in hardness. In addition, the multi-scale HEA can be used as a high-temperature resistant mold for forming thermoplastic materials such as plastics and metallic glasses at temperatures up to 900 °C. Our researches provide candidate materials and novel methods for the facile preparation and various applications of hyperfine structures.

The preparation and structural characterization of the first examples of a β-metallanaphthalyne and tricyclic metallaarynes are described., Metalla-analogs of polycyclic arynes represent an interesting class of metallaaromatics with a formal M 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 1111111111111111111111111111111111 1111111111111111111111111111111111 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 0000000000000000000000000000000000 C bond within the ring. The first examples of a bicyclic β-metallaaryne and tricyclic metallaarynes, including a metallaanthracyne and a metallaphenanthryne, were obtained in good yields by reactions of OsCl2(PPh3)3 with alkyne-functionalized phosphorus ylides.

The application of organic redox-active molecules in aqueous flow batteries demands a deeper understanding of how structures and electrolyte compositions determine solubility. Here we review recent work on anthraquinone derivatives to highlight key factors such as functional groups and counter ions. We discuss the prospect of further increasing solubility and outstanding issues in electrolyte design and solubility measurements.

A rechargeable lithium anode requires a porous structure for a high capacity, and a stable electrode/electrolyte interface against dendrite formation and polysulfide crossover when used in a lithium-sulfur battery. Here, we design two simple steps of spontaneous reactions for protecting porous lithium electrodes. First, a reaction between molten lithium and sulfur-impregnated carbon nanofiber forms a fibrous network with a lithium shell and a carbon core. Second, we coat the surface of this porous lithium electrode with a composite of lithium bismuth alloys and lithium fluoride through another spontaneous reaction between lithium and bismuth trifluoride, solvated with phosphorous pentasulfide, which also polymerizes with lithium sulfide residual in the electrode to form a solid electrolyte layer. This protected porous lithium electrode enables stable operation of a lithium-sulfur battery with a sulfur loading of 10.2 mg cm−2 at 6.0 mA cm−2 for 200 cycles., Stabilizing lithium anodes has been a crucial yet challenging task in developing high-energy batteries. Here the authors design two simple steps of spontaneous reactions to achieve a porous lithium electrode with a composite protective layer, enabling high-loading Li-S batteries with excellent cyclability.

A copper-catalyzed aminobenzannulation of (o-alkynyl)arylketones with amines has been developed. This method features the use of a cheap copper catalyst, the facile annulation involving various amines, and the good functional group tolerance.

The Cu(OAc)2-catalyzed tandem reaction of 2-(1-alkynyl)benzaldimines with water for the synthesis of isoquinolin-1(2H)-ones was developed. Moreover, 4-halogen-substituted isoquinolin-1(2H)-ones were obtained in good yields simply by including N-halosuccinimides (NXS: X = Cl, Br, I) in the reaction system. Mechanistic studies indicated that the reactions are probably initiated by highly regioselective intramolecular cyclization of 2-(1-alkynyl)benzaldimines to give the corresponding isoquinolinium intermediates.

Charge storage in concentrated electrolytes gives redox flow batteries (RFBs) a unique edge in grid-scale energy storage. It also creates a unique challenge in the design of organic molecules as alternatives to expensive vanadium salts. Molecules often come in the form of organic salts, and dissolve by ionic bond breakingand ion solvation, which can hardly be interpreted by “like dissolves like.” Here we use anthraquinone sulfonate salts as a model system to investigate factors underlying their aqueous solubility. We synthesize fifteen salts, measure their solubilities with UV–vis spectroscopy, and find that the solubility of the same quinone could change by three orders of magnitude with a change in its counter-cation. The same impact can come from the position and number of the sulfonate groups. We explain the results with the differences in the ion solvation energy and the lattice energy, the latter of which is corroborated by single-crystal X-ray diffraction. We also derive a simple method to semi-quantitatively predict the solubility of a quinone sulfonate salt based on that of a common sulfate salt. The work provides a physical-chemical base for understanding the solubilities of organic salts for the design of high capacity electrolytes for aqueous flow batteries.

973 Program [2012CB821704]; National Nature Science Foundation of China [20972129]; Science Foundation of Ministry of Education of China [2009060011500466]; Innovative Research Team Program [IRT1036]

Natural Science Foundation of China [21072161, 21302157]; National Basic Research Program of China (973 Program) [2012CB821600]; Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT); Fundamental Research Funds for the Central Universities

A copper-catalyzed aminobenzannulation of (o-alkynyl)arylketones with amines has been developed. This method features the use of a cheap copper catalyst, the facile annulation involving various amines, and the good functional group tolerance.

The Cu(OAc)2-catalyzed tandem reaction of 2-(1-alkynyl)benzaldimines with water for the synthesis of isoquinolin-1(2H)-ones was developed. Moreover, 4-halogen-substituted isoquinolin-1(2H)-ones were obtained in good yields simply by including N-halosuccinimides (NXS: X = Cl, Br, I) in the reaction system. Mechanistic studies indicated that the reactions are probably initiated by highly regioselective intramolecular cyclization of 2-(1-alkynyl)benzaldimines to give the corresponding isoquinolinium intermediates.

The convenient, efficient protocol for the phosphorylation of the title compounds furnishes 2-diarylphosphoryl-substituted products under mild conditions.

Both 3-aryl and 3-alkyl substituted isocoumarins are synthesized by a Rh(III)-catalyzed C—H activation/annulation reaction of electron-rich germinal-substituted vinyl acetates and arylcarboxylic acids.

The Rh(III)-catalyzed C–H activation initiated cyclization of benzoic acids with electron-rich geminal-substituted vinyl acetates was described. The reaction was employed to prepare a range of 3-aryl and 3-alkyl substituted isocoumarins selectively.

Natural Science Foundation of China [21072161, 21302157]; National Basic Research Program of China (973 Program) [2012CB821600]; Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT); Fundamental Research Funds for the Central Universities

A half-sandwich 1,2-azaborolyl (Ab) ruthenium complex, (Ab-C≡CPh)RuCl(PPh3)2 (1), has been synthesized by treating RuCl2(PPh3)3 with lithium 1,2-azaborolide L-1, or by treating either RuCl2(PPh3)3 or RuHCl(PPh3)3 directly with 1,2-azaborole LH-1. It is evaluated as a suitable precatalyst in [2 + 2] cycloadditions of norbornene derivatives with DMAD and in atom transfer radical additions of halogenated compounds with olefins.

Correction for ‘Silver-mediated direct phosphorylation of benzothiazoles and thiazoles with diarylphosphine oxides’ by Hui-Jun Zhang et al., Chem. Commun., 2015, 51, 3450–3453.