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The study investigates the practical application of cyclic wet/dry corrosion tests in simulated industrial atmospheres to assess the impact of chromium (Cr) on the protective properties of vanadium micro‐alloyed weathering steels. Two types of steels were examined: a V‐N steel and a V‐N‐Cr micro‐alloyed weathering steel. These steels were subjected to corrosion tests with 0.01 mol/L NaHSO3 at a pH range of 4.4–4.8 for varying durations. The findings indicate that the inclusion of Cr in the composition of vanadium micro‐alloyed weathering steel enhances corrosion resistance and leads to the accumulation of Cr in the inner rust layer. Furthermore, the distribution of corrosion‐resistant elements (Cr, Ni, Cu, P, and Mo) in V‐N and V‐N‐Cr steels is analyzed. The rust layer was observed to exhibit stratification in the corrosive environment, with the outer layers being dense and uniform, while the inner layers were porous and exhibited poor adhesion to the matrix. The study also delves into the anticorrosion mechanism of vanadium weathering steel using techniques such as X‐ray diffractometer, electron probe microanalysis, and potential‐phase diagram. [ABSTRACT FROM AUTHOR]

The direct ortho‐alkynylation of substituted phenylalanine has been successfully achieved through methoxyiminoacyl (MIA)‐mediated Pd‐catalyzed C−H functionalization. This innovative protocol showcases the ability to apply a diverse range of phenylalanine substrates, resulting in the efficient synthesis of alkynylation benzylamine derivatives with notable effectiveness. Computational investigations further revealed that the fluoride ion enhances the electropositivity of Pd(IV) and the interaction between C1 and C2 within the transition state of the reductive elimination, which significantly expedites the reductive elimination step in the alkynylation process. [ABSTRACT FROM AUTHOR]

The direct acetoxylation of substituted benzylamines has been accomplished through methoxyiminoacyl (MIA)‐mediated Pd‐catalyzed C−H functionalization. A diverse array of phenylalanine substrates is amenable to this protocol, providing acetoxylation benzylamine derivatives with good to high efficiency. Computational results revealed that HOAc enhanced the stability of Pd−O bond, which obviously accelerate the reductive elimination step of the acetoxylation process. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Azithromycin (AZM), a 15‐member macrolide antibiotic, has caused widespread pollution in China, where anaerobic digestion is the predominant wastewater treatment technology. However, the type of anaerobic sludge most suitable for treating antibiotic wastewater is unclear. Therefore, this study aimed to determine the response of anaerobic flocculent and granular sludge to AZM wastewater, and, using a high‐throughput sequencing technique, to explain the diverse microbial community structures. RESULTS: Anaerobic granular sludge provided better resistance to the decline of chemical oxygen demand (COD) removal caused by AZM and greater biodegradation efficiency than flocculent sludge. Furthermore, there was stronger resistance to AZM‐induced reactive oxygen species in the granular sludge than in the flocculent sludge. The granular sludge exhibited richer microbial communities than the flocculent sludge after AZM exposure to the phylum Proteobacteria and Bacteroidetes. CONCLUSION: At high AZM concentration, anaerobic granular sludge was superior to flocculent sludge in COD removal and AZM degradation. This is attributed to less cell death and greater microbial diversity and richness in the granular sludge than in the flocculent sludge following exposure to AZM. Proteobacteria and Bacteroidetes contributed to the resistance to AZM in the granular sludge. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]