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Constructing an internal electric field (IEF) within the hematite (Fe2O3) photoanode for highly efficient water oxidation performance with facilitated charge transfer and separation remains still a significant challenge. Unlike the conventional approach of creating interfacial electric fields through heterojunction design by introducing another semiconductor, a novel strategy is proposed for engineering localized n‐p homojunctions on the surface of Fe2O3 photoanode using gradient Zn2+ doping strategy. By implementing this approach, the inherent n‐type characteristics of Fe2O3 can be transformed into p‐type, thereby facilitating the formation of an n‐p junction with robust IEF, which enables more efficient charge separation and transfer. Additionally, the gradient Zn2+ doping is accompanied by the generation of oxygen vacancies, which further improves the charge transfer efficiency and accelerates water oxidation kinetics. As expected, the photocurrent density of optimized Fe2O3 photoanode at 1.23 V versus reversible hydrogen electrode is ≈2.6‐fold that of Fe2O3. This work provides a novel perspective on the design of localized n‐p homojunction within photoanodes for achieving high solar energy conversion efficiency. [ABSTRACT FROM AUTHOR]

One new citrinin monomer derivative (1), and two new natural products α-pyrone analogues (2a and 2b), were isolated from the sponge derived fungus Penicillium sp. SCSIO 41302. Their structures were determined by extensive spectroscopic analysis, chiral-phase HPLC analysis, modified Mosher's method, ECD calculations, and X-ray single-crystal diffraction. Bioactivity screening showed that compounds 2b and 8 exhibited obvious inhibitory activities against pancreatic lipase and acetyl cholinesterase with IC50 values of 48.5 and 4.8 μM, respectively, which indicated that different chiral center between enantiomers (2a and 2b) might result in different biological activities (IC50 value against PL for 2a >100 μg/ml). [ABSTRACT FROM AUTHOR]

A new diketopiperazine, cyclo-(d-8-acetoxyl-Pro-l-Leu) (1), together with eight known compounds (2–9) including three enterotoxins (2–4), four diketopiperazines (5–8) and maltol (9), were isolated from the mangrove derived-soil Streptomyces sp. SCSIO 41400. The planar structures of all compounds were determined from analysis of NMR spectra, MS, optical rotation and comparing with literature data. The absolute configuration of compound 1 was assigned by electronic circular dichroism (ECD). The isolated compounds (1–9) were tested for their acetyl cholinesterase (AChE) and pancreatic lipase (PL) enzyme inhibitory activities. Among them, the new diketopiperazine (1) displayed preferable PL enzyme inhibitory activity with IC50 value of 27.3 μg/mL, while compounds 2, 5 and 6 showed weak PL enzyme inhibitory activity. Further molecular docking simulation exhibited that compound 1 could be well bind with the catalytic pocket of the PL. Besides, compound 9 showed moderate antibacterial activity against Methicillin-resistant Staphylococcus aureus with MIC value of 12.5 μg/mL, which was comparable to that of the positive control ampicillin with MIC value of 3.125 μg/mL. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li–S) batteries have attracted wide attention due to their outstanding properties of high theoretical specific capacity and energy density. However, drawbacks such as the polysulfide shuttle effect have hampered their further practical application. Metal–organic frameworks (MOFs) have stimulated increasing interest in energy storage and conversion. In MOFs, the metal ions can be activated to provide open metal Lewis acid sites to restrain polysulfides. Aiming at sensible solutions, a novel manganese cluster-based MOF equipped with cubic cages, which are walled with abundant open-metal sites (OMSs) obtained from 9-manganese nodes, is used as the cathode host of Li–S batteries. The activated MOF not only provided physical capture and chemical adsorption against polysulfide shuttle but also allowed efficient impregnation of sulfur to facilitate mass transport. Benefiting from these synergetic effects, the composite cathode delivers enhanced electrochemical performance. The battery showed a remaining capacity of about 990 mA h g−1 after 200 cycles at 0.2C and an approximately repeatable rate performance. Significant contribution of the exposed functional metal sites was demonstrated by XPS and SEM of the electrode materials. [ABSTRACT FROM AUTHOR]

In this paper, 17 compounds (1–17) were isolated from the leaves of Hemp (Cannabis sativa f. sativa). Among the isolates, two were determined to be new spirans: cannabispirketal (1), andα-cannabispiranol 4’-O-β-D-glucopyranose (2) by 1D and 2D NMR spectroscopy, LC-MS, and HRESIMS. The known compounds7,8,10,13,15, and16were isolated from Hemp (C. sativa f. sativa) for the first time. Furthermore, compounds8and13were isolated from the nature for the first time. All isolated compounds were evaluated for cytotoxicity on different tissue-derived passage cancer cell lines through cell viability and apoptosis assay. Among these compounds, compounds5,9and16exhibited a broad-spectrum antitumor effect via inhibiting cell proliferation and promoting apoptosis. These results obtained have provided valuable clues to the understanding of the cytotoxic profile for these isolated compounds from Hemp (C. sativa f. sativa). [ABSTRACT FROM PUBLISHER]

A flexible and highly efficient air cathode is fabricated via a simple electro‐deposition approach. This cathode exhibits a series of considerable electrochemical performances, in particular a good cycling performance (more than 70 cycles with the capacity limited 1000 mA h g−1). Based on this flexible cathode, a Li–O2 battery with flexible properties is also assembled, which can power a commercial LED normally. [ABSTRACT FROM AUTHOR]