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Practical aqueous zinc‐ion batteries require low‐cost thin zinc anodes with long‐term reversible stripping/depositing. However, thin zinc anodes encounter more severe issues than thick zinc, such as dendrites and uneven stripping, resulting in subpar performance and limited lifetimes. Here, this work proposes a three‐in‐one zinc anode obtained by a large‐scale two‐step method to address the above issues. In a three‐in‐one zinc anode, the copper foil as an inactive current collector solves the gradual reduction of the active area when only the pure zinc as an active current collector. This work develops an automatic electroplating device that can continuously deposit a zinc layer on a conducting foil to meet the demand for zinc‐coated copper foils. The sodium carboxymethylcellulose (CMC)‐zinc fluoride (ZnF2) protective layer prevents direct contact between zinc and separator, and provides a uniform and sufficient supply of zinc ions. The CMC‐ZnF2‐coated copper foil performs up to 3000 reversible zinc deposition/stripping cycles with a cumulative capacity of 6 Ah cm−2 and an average Coulombic efficiency of 99.94%. The Zn||ZnVO cell using the three‐in‐one anode achieved a high capacity retention of over 70% after 15 000 cycles. The proposed three‐in‐one anode and the automatic electroplating device will facilitate industrialization of practical thin zinc anodes. [ABSTRACT FROM AUTHOR]

Abstract Silicon (Si), as a quasi-essential element, has a vital role in alleviating the damaging effects of various environmental stresses on plants. Cadmium (Cd) stress is severe abiotic stress, especially in acidic ecological conditions, and Si can demolish the toxicity induced by Cd as well as acidic pH on plants. Based on these hypotheses, we demonstrated 2-repeated experiments to unfold the effects of Si as silica gel on the root morphology and physiology of wheat seedling under Cd as well as acidic stresses. For this purpose, we used nine treatments with three levels of Si nanoparticles (0, 1, and 3 mmol L−1) derived from sodium silicate (Na2SiO3) against three concentrations of Cd (0, 50, and 200 µmol L−1) in the form of cadmium chloride (CdCl2) with three replications were arranged in a complete randomized design. The pH of the nutrient solution was adjusted at 5. The averages of three random replications showed that the mutual impacts of Si and Cd in acidic pH on wheat roots depend on the concentrations of Si and Cd. The collective or particular influence of low or high levels of Si (1 or 3 mM) and acidic pH (5) improved the development of wheat roots, and the collective influence was more significant than that of a single parallel treatment. The combined effects of low or high concentrations of Cd (50 or 200 µM) and acidic pH significantly reduced root growth and biomass while increased antioxidants, and reactive oxygen species (ROS) contents. The incorporation of Si (1 or 3 mmol L−1) in Cd-contaminated acidic nutrient solution promoted the wheat root growth, decreased ROS contents, and further increased the antioxidants in the wheat roots compared with Cd single treatments in acidic pH. The demolishing effects were better with a high level of Si (3 mM) than the low level of Si (1 Mm). In conclusion, we could suggest Si as an effective beneficial nutrient that could participate actively in several morphological and physiological activities of roots in wheat plants grown under Cd and acidic pH stresses.

An electrochemical method for the decarboxylative alkylation of β-ketoacids with phenol derivatives has been developed. The protocol was carried out in readily available unseparated cells at room temperature in the absence of catalysts and oxidants. The corresponding aryl ketones were obtained in satisfactory yields without additional electrolytes, and were easy to produce in gram-scale synthesis. Based on control experiments and cyclic voltammetry, a plausible reaction mechanism was proposed. [ABSTRACT FROM AUTHOR]

Hairpin DNA containing split G-quadruplex at its terminus displayed tagging position-dependent horseradish peroxidase activity. In general, the hairpin DNA coupled with one GGG repeat at its 5'-terminus and three GGG repeats at its 3′-terminus demonstrated strong catalytic activity, while slight activity was observed after exchanging the position of split G-quadruplex sequence. Inspired by these observations, a novel colorimetric biosensor for nuclease activity assay was developed by selecting S1 nuclease as the model. Specifically, S1 nuclease cleaves the split G-quadruplex into mono- or oligonucleotide fragments, thereby suppressing the catalytic activity, accompanied by a color change from blue to colorless. Under optimum conditions, S1 nuclease was determined with a linear range from 1.60 to 17.6 U/mL and a detection limit of 1.458 U/mL. The constructed method was simple and did not require complex sequence design, expensive instrumentation, and probe labeling. Most importantly, this work facilitates a better understanding of the catalytic mechanism of the DNAzyme and provides an example of the practical application of G-quadruplex-based DNAzyme. [ABSTRACT FROM AUTHOR]