Cocatalysts have been extensively used to accelerate the rate of hydrogen evolution in semiconductor-based photocatalytic systems, but the influence of interface state between semiconductor and cocatalyst has been rarely investigated. Here, we demonstrate a feasible strategy of two-dimensional (2D) nanojuctions to enhance solar hydrogen generation of the MoS2/TiO2 system. Loading of 2D MoS2 nanosheets on the surface of 2D anatase TiO2 nanosheets with exposed (001) facets greatly increases the interfacial contact. At an optimal ratio of 0.50 wt % MoS2, the 2D-2D MoS2/TiO2 photocatalyst shows the highest H2 evolution rate of 2145 μmol h–1 g–1, which is almost 36.4 times higher than that of pure TiO2 nanosheets. The apparent quantum yield of hydrogen evolution system reaches 6.4% at 360 nm. More importantly, the 2D-2D MoS2/TiO2 composite exhibits photocatalytic activity much higher than those of noble metal (such as Pt, Rh, Ru, Pd, and Au) loaded TiO2 photocatalysts. The decisive factor in improving the photocatalytic H2 production activity is an intimate and large contact interface between the light-harvesting semiconductor and cocatalyst. The effective charge transfer from TiO2 to MoS2 is demonstrated by the significant enhancement of photocurrent responses in 2D-2D MoS2/TiO2 composite electrodes. This work creates new opportunities for designing and constructing highly efficient photocatalysts by interface engineering.

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Two new iridoid glycosides (1 and 2), together with the known compounds barlerin (3) and verbascoside (4), were isolated from Barleria prionitis. The new iridoid glycosides were determined to be 6-O-trans-p-coumaroyl-8-O-acetylshanzhiside methyl ester (1) and its cis isomer (2) by using spectroscopic, especially 2D NMR, data. A 3:1 mixture of 1 and 2 was shown to have potent in vitro activity against respiratory syncytial virus (EC50 2.46 microgram/mL, IC50 42.2 microgram/mL).

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Irlbacholine and a series of related analogues were synthesized and their antifungal activities against Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus were assessed. The natural bisphosphocholine, irlbacholine, was the most potent compound, its 22-carbon chain length appearing to be optimal.

Based on the restraining effect that spatial filtering has on the frequency spectrum of a beam, from the small-scale focusing theory of Bespalov and Talanov (B-T theory) we derive an expression for the pinhole diameter of the spatial filter corresponding to the fastest growing frequency. Then, compared with the theoretical pinhole diameter of the spatial filter, the restraining effect of the spatial filter on a hot image with different pinhole diameters is numerically investigated. The numerical results show that, if the pinhole diameter is larger than the theoretical one, the hot-image intensity will remain steady; once the pinhole diameter becomes smaller than the theoretical one, the hot-image intensity will begin to decrease. Moreover, as the pinhole diameter decreases, a more prominent restraining effect can be obtained. But reducing the diameter of the spatial filter would lead to greater beam energy loss. The parameters of the spatial filter must be chosen to guarantee that the scheme fulfills the demand for low beam energy loss and a satisfactory restraining effect simultaneously.

A phytochemical study on the methanol extracts from the seeds of Peganum harmala L. led to a new quizonaline alkaloid (S)-vasicinone-1-O-β-d-glucopyranoside (1) and four known ones, (R)-vasicinone-1-O-β-d-glucopyranoside (2), (S)-vasicinone (3), vasicine (4), and deoxyvasicinone (5). Their structures were elucidated by spectroscopic analysis including IR, HR-ESI-MS, 1D and 2D NMR, and specific rotation as well as by comparison of the data with those in the literature. All of the alkaloids were screened for antiproliferative activity against human gastric cancer cells MCG-803 with MTT method. Compounds 1 and 3 exhibited moderate inhibitory activity.

Chitosan oligosaccharides can alleviate liver endoplasmic reticulum stress to improve lipid metabolism and reduce obesity caused by high-fat diet.