To avoid the energy‐consuming step of direct N≡N bond cleavage, photocatalytic N2 fixation undergoing the associative pathways has been developed for mild‐condition operation. However, it is a fundamental yet challenging task to gain comprehensive understanding on how the associative pathways (i.e., alternating vs. distal) are influenced and altered by the fine structure of catalysts, which eventually holds the key to significantly promote the practical implementation. Herein, we introduce Fe dopants into TiO2 nanofibers to stabilize oxygen vacancies and simultaneously tune their local electronic structure. The combination of in situ characterizations with first‐principles simulations reveals that the modulation of local electronic structure by Fe dopants turns the hydrogenation of N2 from associative alternating pathway to associative distal pathway. This work provides fresh hints for rationally controlling the reaction pathways toward efficient photocatalytic nitrogen fixation.

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Photocatalytic CO2 reduction coupled with water oxidation provides a fascinating approach to mitigating the issues of global warming and energy shortage. Herein, a direct Z-scheme heterojunction of Co1-C3N4@α-Fe2O3 comprising g-C3N4-supported...

Solar energy-driven direct CH4 conversion to liquid oxygenates provides a promising avenue toward green and sustainable CH4 industry, yet still confronts issues of low selectivity toward single oxygenate and use of noble-metal cocatalysts. Herein, for the first time, we report a defect-engineering strategy that rationally regulates the defective layer over TiO2 for selective aerobic photocatalytic CH4 conversion to HCHO without using noble-metal cocatalysts. (Photo)­electrochemical and in situ EPR/Raman spectroscopic measurements reveal that an optimized oxygen-vacancy-rich surface disorder layer with a thickness of 1.37 nm can simultaneously promote the separation and migration of photogenerated charge carriers and enhance the activation of O2 and CH4, respectively, to •OH and •CH3 radicals, thereby synergistically boosting HCHO production in aerobic photocatalytic CH4 conversion. As a result, a HCHO production rate up to 3.16 mmol g–1 h–1 with 81.2% selectivity is achieved, outperforming those of the reported state-of-the-art photocatalytic systems. This work sheds light on the mechanism of O2-participated photocatalytic CH4 conversion on defective metal oxides and expands the application of defect engineering in designing low-cost and efficient photocatalysts.

A water-soluble polysaccharide named DI was extracted from the fruiting bodies of gastroid mushroom Dictyophora indusiata with boiling water. The chemical and physical characteristics of DI were investigated by a combination of chemical and instrumental analysis methods. The immunomodulatory activities on RAW 264.7 macrophage of DI in vitro were also studied. The results showed that DI is a β-(1→3)-glucan with side branches of β-(1→6)-glucosyl units, and it has triple-helical structure. DI has no toxic effect on cells, but can promote macrophage multiplication. DI significantly affects the immune function by promoting the production of nitric oxide and cytokines, such as tumor necrosis factor-α, interleukin-1, -6, and -12, showing an obvious dose-effect relationship. This work extends the application scope of the polysaccharide from D. indusiata in the biomedical field.

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The relationships among the generation of acoustic emission, electromagnetic emission, and the fracture stress of rock grain are investigated, which are based on the mechanism of acoustic emission and electromagnetic emission produced in the process of indenting rock. Based on the relationships, the influence of loading rate on the characteristics of acoustic emission and electromagnetic emission of rock fragmentation is further discussed. Experiment on rock braking was carried out with three loading rates of 0.001 mm/s, 0.01 mm/s, and 0.1 mm/s. The results show that the phenomenon of acoustic emission and electromagnetic emission is produced during the process of loading and breaking rock. The wave forms of the two signals and the curve of the cutter indenting load show jumping characteristics. Both curves have good agreement with each other. With the increase of loading rate, the acoustic emission and electromagnetic emission signals are enhanced. Through analysis, it is found that the peak count rate, the energy rate of acoustic emission, the peak intensity, the number of pulses of the electromagnetic emission, and the loading rate have a positive correlation with each other. The experimental results agree with the theoretical analysis. The proposed studies can lead to an in-depth understanding of the rock fragmentation mechanism and help to prevent rock dynamic disasters.