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The permeable pavement plays an important role in mitigating urban flooding. In order to explore the relationship between materials and properties to better guide the practical production of resin-based permeable bricks, 10 kinds of representative aggregate samples with obvious different characteristics were selected for preparation. In this study, Image Pro Plus was used to binarize the acquired image pictures of the aggregate so as to obtain particle group characteristic parameters. The properties and porosity of the brick were measured in order to describe the influence of the material. The results are as follows. The relative standard deviation of aggregate and the amount of cementing material are negatively related to the compressive strength of permeable bricks, but positively related to water permeability and filtration performance. The roundness and roughness of the aggregate are the opposite. Furthermore, the porosity of the permeable brick is the essential reason for this phenomenon, that is, as the porosity increase, the compressive strength decrease, but the water permeability and the filtration performance become better. In the end, an optimization method for the compatibility of resin-based pavement permeable bricks was proposed through reflecting all factors in a two-bit flat grayscale image which can be applied in performance prediction and guidance of material selection.

The slow reaction kinetics of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) during the charging and discharging process result in inferior cycle life and low-energy conversion efficiency of commercial zinc-air batteries (ZABs). Stannic oxide (SnO2) has received increasing attention for its unique advantages such as low cost, good stability, and high catalytic activity. In present work, mesoporous nanosphere carbon@stannic oxide (C@SnO2) core–shell structures with C as the inner layer and SnO2 as the outer shell are successfully prepared. When C@SnO2 serves as the cathode for ZABs, its specific surface area (245 m2 g−1) provides amounts of chemically active sites for ORR and OER. Similarly, carbon can not only increase the electrical conductivity of electrocatalyst, but also act as a support body for the core–shell structure which gives the material a robust structure and distinctive morphology. When C@SnO2 are employed as cathode in ZABs, it exhibits excellent electrocatalytic activity with half-wave potential (0.88 V) for ORR and onset potential (1.45 V) for OER. In addition, it shows a superior charging-discharging cycle stability. This work offers an insight for the selection and preparation of high-performance electrocatalysts. [ABSTRACT FROM AUTHOR]

The excellent photoresponse of semiconductors enables them as a promising photocatalyst for photocatalytic degradation of organic pollutants and antibiotics, but their practical applications are limited by photogenerated carrier recombination, instability, and fixed energy band positions. Herein, we designed and synthesized a dual Z-scheme flower-like spherical Ag3PO4/MoS2/g-C3N4 (AMN) photocatalyst loaded with different mass of g-C3N4 (3, 5 and 7 mg). Under visible light irradiation, MoS2 enhanced the light absorption range of AMN composite. The holes concentrated in the valence band of Ag3PO4 provide strong oxidation capacity, and the electrons retained in conduction band of g-C3N4 provide strong reduction ability in the photocatalytic system. It is helpful to improve the separation efficiency of photogenerated carriers and enhance the photocatalytic activity of AMN composite. The AMN photocatalyst loaded with 5 mg g-C3N4 (AMN-5) has the optimal photocatalytic activity. The photocatalytic degradation efficiency of the photocatalyst for methylene blue (MB) within 24 min is 3.98, 1.85, and 1.17 times that of g-C3N4, Ag3PO4, and Ag3PO4/MoS2, respectively. After three cycles, the degradation efficiency of AMN-5 for MB decreased from 99.44% to 90%, about 3.79 times of Ag3PO4 (23.77%). In addition, the optimal AMN-5 photocatalyst also has excellent photocatalytic degradation efficiency for Rhodamine B (RhB) and tetracycline (TC). This design and concept provide a promising insight for the photocatalytic degradation of pollutants. [ABSTRACT FROM AUTHOR]