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Aqueous rechargeable zinc‐metal‐based batteries are an attractive alternative to lithium‐ion batteries for grid‐scale energy‐storage systems because of their high specific capacity, low cost, eco‐friendliness, and nonflammability. However, uncontrollable zinc dendrite growth limits the cycle life by piercing the separator, resulting in low zinc utilization in both alkaline and mild/neutral electrolytes. Herein, a polyacrylonitrile coating layer on a zinc anode produced by a simple drop coating approach to address the dendrite issue is reported. The coating layer not only improves the hydrophilicity of the zinc anode but also regulates zinc‐ion transport, consequently facilitating the uniform deposition of zinc ions to avoid dendrite formation. A symmetrical cell with the polymer‐coating‐layer‐modified Zn anode displays dendrite‐free plating/stripping with a long cycle lifespan (>1100 h), much better than that of the bare Zn anode. The modified zinc anode coupled with a Mn‐doped V2O5 cathode forms a stable rechargeable full battery. This method is a facile and feasible way to solve the zinc dendrite problem for rechargeable aqueous zinc‐metal batteries, providing a solid basis for application of aqueous rechargeable Zn batteries.

Seven new metabolites, 3‐hydroxy‐1‐(2,6‐dihydroxyphenyl)butan‐1‐one (1), 1‐(2‐hydroxy‐6‐methoxyphenyl)butan‐1‐one (3), 2,3‐dihydro‐5‐methoxy‐2‐methylchromen‐4‐one (6), the dimeric naphthalenes nodulisporin A (9) and B (10), and the first naturally occurring dimeric indanone, nodulisporin C (12), as well as (4E,6E)‐2,4,6‐trimethylocta‐4,6‐dien‐3‐one (13) were isolated together with ten known compounds (2, 4, 5, 7, 8, 11, 14–17) from the culture extract of the endophytic fungus Nodulisporium sp. from Juniperus cedre from Gomera Island. The structure of dictafolin‐A, previously erroneously assigned as structure 6, is not identical with 2,3‐dihydro‐5‐methoxy‐2‐methylchromen‐4‐one, isolated in this investigation. The structures of new compounds were determined by spectroscopic methods (mainly extensive 1D and 2D NMR experiments and mass spectral measurements) and X‐ray single crystal analysis. All but one of the thirteen tested compounds exhibit herbicidal, antifungal and/or antibacterial activities. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Aqueous rechargeable batteries (ARBs) have become a lively research theme due to their advantages of low cost, safety, environmental friendliness, and easy manufacturing. However, since its inception, the aqueous solution energy storage system has always faced some problems, which hinders its development, such as the narrow electrochemical stability window of water, poor percolation of electrode materials, and low energy density. In recent years, to overcome the shortcomings of the aqueous solution-based energy storage system, some very pioneering work has been done, which also provides a great inspiration for further research and development of future high-performance aqueous energy storage systems. In this paper, the latest advances in various ARBs with high voltage and high energy density are reviewed. These include aqueous rechargeable lithium, sodium, potassium, ammonium, zinc, magnesium, calcium, and aluminum batteries. Further challenges are pointed out.

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Enery storage is a vital issue to be solved for the efficient utilization of renewable energies such as solar, wind and tidal energy. In terms of rechargeable battery energy storage,...

As a result of recent insights in the molecular structures and medicinal uses of the tannins, this class of natural products has enjoyed renewed scientific interest. This is reflected on the one hand in the enormously increased number of publications reporting on the isolation, characterization and biological activity of the tannins, and on the other hand in the steadily growing number of papers reporting tannin syntheses. In this review the most recent advances in the total synthesis of ellagitannins are discussed. In nature the ellagitannins occur usually only as the R-or only as the S-configured atropisomer, while the corresponding opposite atropisomers are seldom found. The configuration of the hexahydroxydiphenoyl units (HHDP's) found in ellagitannins is usually determined by the linkage position of the HHDP's with the polyol residues of the ellagitannins. Those ellagitannins of which the HHDP's are linked to the 2,3-or 4,6-positions of D-glucopyranose, have the S configuration; the corresponding 3,6-(HHDP)-ellagitannins are R-configured. Very few exceptions exist where both atropisomers are known. With one atropisomer showing the "normal" configuration, the other atropisomer is usually indicated in the literature as "unusual ellagitannin". This observed strict atropodiastereoselectivity in the biosynthesis of normally configured and unusual ellagitannins has led to the formulation of several hypotheses, which will be examined, in addition to the overview of effective concepts and strategies for the synthesis of ellagitannins.