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• Cu coating was successfully fabricated on cement paste by CTAB-assisted electrodeposition. • 0.5 g/L CTAB induced better deposition on the hardened cement paste surface. • Cu-coated cement paste presented excellent antibacterial performances. [ABSTRACT FROM AUTHOR]

• Impact of four cations on stability of bound chloride under electric field and SO 4 2− was studied. • Bound chloride was prone to converting into free chloride under electric field and SO 4 2− attack. • Divalent cations exerted a more negative effect on the stability of bound chloride ions. • Destabilization of bound chloride was due to decomposition of C-S-H gels and Friedel's salts. Destabilization and release of bound chloride ions in reinforced concrete structures can cause accelerated corrosion of steel bars, posing an attendant risk to the durability of the whole structure and this problem is exacerbated by the combined effect of SO 4 2− and electric field. In this paper, electrochemical chloride removal (ECR) method was used to remove chloride ions from mortar specimens and the influence of four cations (Mg2+, Ca2+, Na+ and K+) on the stability of bound chloride ions in cement mortars simultaneously under an electric field and SO 4 2− attack was investigated. The results showed that bound chloride ions were prone to converting into free chloride ions under the combined effect of electric field and SO 4 2− attack. Moreover, divalent cations (Mg2+ and Ca2+) exerted a more negative effect on the stability of bound chloride ions than monovalent cations (Na+ and K+). X-ray diffraction (XRD) analysis and thermal gravimetric and differential thermal gravimetric (TG-DTG) analysis demonstrated that the destabilization of bound chloride ions under an electric field was mainly attributed to the decomposition of the C-S-H gels and Friedel's salts. Findings from this research shed new light on the fate of bound chloride ions in reinforced concrete structures under an electric field in chloride-sulfate coexistence environments. [ABSTRACT FROM AUTHOR]

• A short-term analysis of a IFAS-MBR system was carried out over a two-year survey. • The system performance was mostly affected by the influent C/N ratio variation. • Biofilm on the carriers was able to sustain nitrification even at low SRTs. • A kinetic specialization of the two biomasses was highlighted by respirometry. • Possible to operate the system at low mixed liquor SRTs enhancing PAO activity. The present paper investigated an Integrated Fixed Film Activated Sludge (IFAS) Membrane BioReactor (MBR) system monitored for 340 days. In particular, the short-term effects of some operational parameters variation was evaluated. Results showed a decrease of the removal rates under low C/N values. Respirometry results highlighted that activated sludge was more active in the organic carbon removal. Conversely, biofilm has a key role during nitrification. The major fouling mechanism was represented by the cake deposition (irreversible). [ABSTRACT FROM AUTHOR]

• Focus was placed on effect of electro-deposition on microstructures of concrete. • Electro-deposition exerted negligible influences on mineral compositions of samples. • Electro-deposition improved overall compactness of samples. The electro-deposition technique can be used to repair cracks in reinforced concrete. Inevitably, this treatment affects the physical and chemical properties of the reinforced concrete. However, scant research has focused on the effect of electro-deposition on the microstructures of concrete. This study investigated the changes in the compositions and morphology of reinforced concrete with cracks after electro-deposition treatment. The results showed that the electro-deposition treatment exerted negligible influences on the mineral compositions of mortar specimens. However, the overall compactness of mortar was significantly improved with a reduction in the total porosity and refinement in the most probable pore size. Microstructure observation revealed that deposits, such as Mg (OH) 2 and ZnO, were distributed and accumulated on the interface between aggregates and hardened cement paste, which contributed to the improvement in the overall compactness of the mortar samples. [ABSTRACT FROM AUTHOR]