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This paper presents a new type of checkered steel-encased concrete composite beam, which utilizes a convex checkered pattern in the steel beam to improve the bonding effect between steel and concrete and their cooperative performance. In theory, the checkered pattern arrangement can effectively reduce the number of bolts and enhance the slipping-resistance property of the composite beam. Thus, the new pattern improves the mechanical behavior of the composite beam. To investigate the real bending and slipping performance of the new-type composite beam, the authors conducted static load tests on six simply-supported beams. These tests enabled a thorough analysis of the experimental process of failure, load-deflection curves, strain distribution curves, load-slipping curves and slip distribution curves along the six specimen beams. The experimental results showed that given the same sectional dimensions and reinforcements, as the anti-slipping connection degree of the new-type composite beam increases, its flexural bearing capacity and ductility increase, the end slip decreases, and the failure mode of specimen changes from shear slip failure to bending failure. Based on our experiments, new theoretical formulas are given to calculate the slip and deflection of the new checkered pattern composite beams. These calculations effectively prove the bonding effect value between the checkered steel plate and concrete. The elastic and ultimate bending capacity of the composite beams were derived, considering the additional deflection caused by slip effect. It has been shown that theoretical values of the deflection and bending capacity calculated by the formulas are in agreement with experimental values. [ABSTRACT FROM AUTHOR]

The exploration of efficient heterogeneous catalysts for persistent organic pollutant removal is extremely attractive. In the present work, MnO 2 /Mn 3 O 4 photo-Fenton catalysts were designed by a facile hydrothermal route to activate peroxymonosulfate (PMS) under visible light irradiation for organic pollutant degradation. The optimized MnO 2 /Mn 3 O 4 heterojunction shows excellent Rhodamine B (RhB) removal efficiency, whose apparent kinetic constant is 11.9 and 5.36 times as high as the MnO 2 and Mn 3 O 4. Meanwhile, there is a neglectable attenuation in catalytic performance after 5 recycling runs. Based on the active species trapping experiments, the non-radical process contributes more than the radical process during RhB degradation. Moreover, factors including the dosage of PMS, initial RhB concentration, initial pH, the presence of various anions, different organic pollutants, and water sources are investigated. Systematical characterizations reveal that the enlarged specific surface areas and the efficient charge separation aroused from the Z-scheme mechanism are attributed to the enhanced photo-Fenton performance. The present work contributes to the construction of the Mn-based photo-Fenton catalyst with efficient PMS activation capacity for environmental remediation. [Display omitted] • MnO 2 nanosheet/Mn 3 O 4 octahedron heterojunctions are successfully constructed. • The fabricated hybrid photocatalyst exhibits superior photo-Fenton catalytic performance. • The non-radical process plays the main role in RhB degradation. • The separation and transfer efficiency of charge carriers are effectively improved via the Z-scheme charge transfer path. [ABSTRACT FROM AUTHOR]

Abstract: Thirty-eight 3-aryl-4-acyloxyethoxyfuran-2(5H)-ones were designed, prepared and tested for antibacterial activities. Some of them showed significant antibacterial activity against Gram-positive organism, Gram-negative organism and fungus. Out of these compounds, 4-(2-(3-chlorophenylformyloxy)ethoxy)-3-(4-chlorophenyl)furan-2(5H)-one (d40) showed the widest spectrum of activity with MIC50 of 2.0μg/mL against Staphylococcus aureus, 4.3μg/mL against Escherichia coli, 1.5μg/mL against Pseudomonas aeruginosa and 1.2μg/mL against Candida albicans. Our data disclosed that MIC50 values against whole cell bacteria are positive correlation with MIC50 values against tyrosyl-tRNA synthetase. Meanwhile, molecular docking of d40 into S. aureus tyrosyl-tRNA synthetase active site was also performed, and the inhibitor tightly fitting the active site might be an important reason why it has high antimicrobial activity. [Copyright &y& Elsevier]