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The performance of reactive powder concrete (RPC) is much higher than that of ordinary concrete, and the engineering application is gradually increasing. The bond failure process and bond slip between RPC and reinforcement will show new characteristics. It is necessary to study the bond behavior between RPC and steel bar. The direct drawing test was carried out on the 36 bonding specimens in order to study the bond performance between steel bar and reactive powder concrete. The research shows that the cohesive force consists of three parts: the mechanical bite force produced by the mechanical occlusion between the reinforcing rib and the RPC; The cementing force produced by chemical reaction between RPC component and surface material of reinforcement; Friction between reinforcement and surrounding RPC. The application of ultrahigh strength and various cementitious materials make the Bonding strength between rebar and RPC significantly higher than that of normal concrete. This study can provide reference for the reinforcement anchorage design of RPC structure.

A novel visible-light driven ZnFe 2 O 4 /Ag/Ag 3 VO 4 photocatalyst was successfully fabricated through a two-step hydrothermal method. The structure, morphology and composition of the samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray photo-electron spectroscopy (XPS). The as-prepared ZnFe 2 O 4 /Ag/Ag 3 VO 4 composites possessed an excellent performance in the photocatalytic degradation of methyl orange and tetracycline under visible-light irradiation. The results of electrochemical impedance spectroscopy (EIS) indicated that the ZnFe 2 O 4 /Ag/Ag 3 VO 4 composite could facilitate the separation of photo-generated carriers, as well as accelerated charge transfer. The 5% ZnFe 2 O 4 /Ag/Ag 3 VO 4 composite exhibited the upmost photocatalytic activity, the degradation constant of 5% ZnFe 2 O 4 /Ag/Ag 3 VO 4 is as high as 1.49 times to that of Ag/Ag 3 VO 4 . Also, according to the trapping experiments, it’s found that the superoxide radicals ( O 2 − ) and hole (h + ) were the predominant reactive species in this system. The ZnFe 2 O 4 /Ag/Ag 3 VO 4 photocatalyst is promising for designing as an environmental purification material in treatment of antibiotic pollutant.

Flower-like zinc oxide (ZnO) nanoparticles were synthesized with sodium hydroxide and zinc acetate in a cellulose hydrogel microreactor (prepared by the inversion method). The samples were characterized by scanning electron microscopy, EDX, x-ray diffractometry, ultraviolet-visible diffuse reflection spectroscopy, and nitrogen adsorption-desorption. The results indicated that ZnO grows in a flower-like shape in the pores of the cellulose hydrogel. The pure hexagonal wurtzite structures have uniform diameters in the range of 10 nm to 30 nm, surface areas of 39.18 m2/g, and pore volumes of 0.2109 cm3/g. This study also investigated the photocatalytic properties. The nanoparticles have a band gap of 3.23 eV and a 95.2% efficiency for the ultraviolet degradation of rhodamine B over 3 h at room temperature.