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Highlights • The effect of MK based materials on the steam cured high performance concrete is investigated. • The XRD and TG analysis were applied to quantify the content of CH and AFt after curing. • The MK based admixtures remarkably refines the ITZ and optimize the pore structure of concrete after heat treatment. Abstract High performance pipe piles are widely used in precast industry. In order to improve the production efficiency and performances of the products, steam curing and mineral admixtures are usually applied. This paper evaluates the performances of HPC pipe piles produced with metakaolin-based admixtures. Quantitative phase composition analysis shows that the addition of 10 wt% metakaolin reduces the portlandite content by up to 57.1%, while increases the content of ettringite to some extent. The addition of metakaolin or metakaolin-slag/limestone blends improves the mechanical properties, especially the hybrid usage of metakaolin and limestone filler. Pore structure and microscope analyze confirm the remarkably-refined pore characteristics caused by the addition of metakaolin-based admixtures, in which case the gel pores accounts up to 85% of the total pores. Those remarkably improved properties caused by the addition of metakaolin-based admixtures indicate a promising future for their applications in producing high performance pipe piles with further modified properties. [ABSTRACT FROM AUTHOR]

Abstract: A novel series of compounds containing fluoranthene and triphenylamine were designed and synthesized as electroluminescent materials or sensitizers. Photophysical and electrochemical measurements were carried out on these compounds. DPBF exhibited a maximum current efficiency of 1.3cd/A (1.00lm/W at 5.17V) and D2 had the maximum light-to-electricity efficiency of 4.57% under AM 1.5 solar simulator (100mWcm−2). The results suggest that bistriphenylamine-substituted fluoranthene derivatives have the potential application in optoelectronic materials. [Copyright &y& Elsevier]

In this research, three highly efficient combination systems, including constructed wetland microbial fuel cell (CWMFC), hydrolytic sludge acidification coupling with constructed wetland microbial fuel cell (HSA-CWMFC) and hydrolytic filler acidification coupling with constructed wetland microbial fuel cell (HFA-CWMFC), were applied to the removal of pollutants from domestic sewage. The three combination systems could effectively treat domestic sewage and generate clean energy. The power generated by CWMFC, HSA-CWMFC, and HFA-CWMFC was 0.36 W/m2, 0.40 W/m2, and 0.43 W/m2, respectively. The results indicated that the removal rates of chemical oxygen demand (COD), total organic carbon (TOC), total phosphorus (TP), ammonia nitrogen (NH 3 –N), and nitrate nitrogen (NO 3 −-N) in HFA-CWMFC could achieve the optimal values of 91.01%, 90.63%, 95.35%, 86.11%, and 91.01%, respectively. In addition, HFA-CWMFC produced more organic acids than HSA-CWMFC, which was beneficial to the follow-up reaction. Through qualcomm sequencing analysis, it could be seen that Firmicutes , which could enhance power generation capacity and increase removal rates of pollutants, played an important role in HFA-CWMFC. The results demonstrated that the three combined systems had excellent application prospects for sewage treatment and energy generation. [Display omitted] ● The hydrolytic combination systems had remarkable effect on pollutants removal. ● The hydrolytic filler combination system could obviously remove pollutants. ● Microbial community in the hydrolytic filler combination system was more abundant. [ABSTRACT FROM AUTHOR]

Abstract: Six new organic dyes, TBS1–TBS6, have been synthesized and characterized by optical, electrochemical, and theoretical studies. Among these dyes, DSSCs based on a dye containing N-hexylcarbazole and furan moieties (TBS4) showed the best performance, with light-to-electricity conversion efficiency up to 5.91% under AM 1.5 solar simulator, much higher than the reference dye TPS (4.24%). The high V oc contributed to the good performance for TBS4, which may be ascribed to the combined effects of twisted structure and hexyl chain. Additionally, for TBS4 based DSSCs, under optimized conditions, the light-to-electricity conversion efficiency was enhanced up to 7.09%. The results suggest that dibenzo heterocycles containing dyes are promising candidates for application in DSSCs. [Copyright &y& Elsevier]

In this research, Ti/SnO 2 –RuO 2 stable anode was successfully prepared by thermal decomposition method, and low concentration cefotaxime sodium (CFX) was degraded by green and sustainable electrocatalytic oxidation technology. The electrocatalytic activity and stability of the Ti/SnO 2 –RuO 2 coating electrode were studied according to the polarization curve of oxygen and chlorine evolution. The effects of current density, initial concentration, pH, electrolyte concentration, and other technological parameters on the degradation efficiency were discussed. Orthogonal experiment results indicated that when the current density was 25 mA cm−2, concentration of electrolyte was 5 mM and the pH value was 7, the best CFX removal rate of 86.33% could be obtained. The degradation efficiency of electrocatalytic oxidation was discussed through electrochemical analysis. Fourier transform infrared spectroscopy was used to analyze the different inlet and outlet stages before and after the degradation of CFX, and the possible degradation process was discussed. Therefore, the electrocatalytic oxidation of Ti/SnO 2 –RuO 2 electrode was a clean and efficient technology, which could be widely used in the treatment of CFX wastewater. [Display omitted] • SnO 2 and RuO 2 are used as dopant to DSA to the degradation of cefotaxime sodium. • Ti/SnO 2 –RuO 2 anode displays excellent stability and electrochemical activity. • ·OH and ClO− play a decisive role in the removal of cefotaxime sodium. • Cefotaxime sodium removal efficiency of 86.33% is reached. [ABSTRACT FROM AUTHOR]

• PVA modification has adverse effect on the compressive strength of ECC. • Nanomaterials act on the early stage of ECC toughness improvement. • Modified PVA act on the whole cycle of ECC toughness improvement. Nanomaterial modification and fiber reinforcement are both effective modifications for concrete toughening. In this study, the cement matrix was reinforced by a combination of nanomaterials and surface-modified polyvinyl alcohol (PVA). The modification of PVA involves the treatment of interface weakening, which is based on the enhancement of the slip effect. The workability and static mechanical properties of engineered cementitious composites (ECCs) were studied, and the micromorphology of the fiber and matrix after bending failure was observed through scanning electron microscopy. Different nanomaterial contents and concentrations of PVA were designed in the experiment, the purpose of which is to investigate the mechanism of the effect of multiple superposed on the toughening effect of ECCs. The research demonstrated that the direct addition of traditional PVA fiber and nanomaterials adversely affects the workability of ECCs, but it can be improved by fiber modification and ultrasonic dispersion of nanomaterials. An experimental study on the compressive properties showed that, with the increase in PVA fiber modification concentration, the compressive strength decreased, but the addition of nano-CaCO 3 improved the strength of the matrix, thereby compensating for the strength loss. Four-point bending and tensile tests demonstrated that both PVA fiber modification and the addition of nano-CaCO 3 affected the flexural properties of ECCs to some extent. PVA fibers modified with 1% and 2% nano-CaCO 3 at vinyl acetate ethylene concentrations of 25% and 50% can improve the toughness of ECCs. Nano-CaCO 3 can improve the toughness of ECCs by improving the compactness of the matrix structure and fiber interface, while PVA fiber can supplement the defects of the matrix structure by bridging and sliding and have a positive superposition effect on the toughness of the material after proper treatment. [ABSTRACT FROM AUTHOR]

Quarry stone powder is one of the solid waste, which can create obvious environmental risks. To solve this problems, 22.2%–44.4% of cement is replaced by two types of quarry stone powder (basalt and limestone powders) in producing an environmentally-friendly ultra-high performance concrete (UHPC) in this study. The material mix design is followed on the basis of the modified Andreasen and Andersen (MAA) model. Then, the impact of the quarry stone powders on fresh and hardened properties of UHPC are investigated, including flowability, compressive strength, early hydration kinetics, and durability. The results indicate that the incorporation of quarry stone powder can significantly improve the flowability, slow down the early hydration rate of cement and decrease autogenous shrinkage of UHPC during early age. Besides, the addition of quarry stone powder could decrease the strength of UHPC at 7 days, while its strength is comparable with the reference mix at 56 days. The carbon dioxide (CO 2) emissions calculation shows that application of quarry limestone powder can significantly reduce the environmental burden of UHPC, which means the produced UHPC can be treated as a green building material with advanced properties in the near future. • Quarry stone powders can be used to produce eco-friendly UHPC. • The flowability of UHPC was improved by including stone powder. • Autogenous shrinkage of UHPC can be reduced by adding quarry stone powder. • The produced UHPC with quarry stone powders has good durability. • The microstructure of the produced UHPC with quarry stone powders is dense. [ABSTRACT FROM AUTHOR]