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Municipal solid waste incineration (MSWI) fly ash is a by-product of garbage incineration power generation, and its disposal is currently a world problem because it contains over standard heavy metals. This research aims to solidify the heavy metals in MSWI fly ash and make it to be utilizable construction materials under the guidance of intermediate-calcium cementitious materials (ICCM), and meanwhile figure out the solidification and hydration mechanism. The hydration characteristics of ICCM were characterized by XRD, FTIR, 29 Si MAS-NMR and SEM techniques, and the environmental properties are investigated by TCLP and EPMA. The results indicate that the optimal ratio of (CaO + MgO)/(SiO 2  + Al 2 O 3 ) for ICCM is at the range of 0.76–0.88. The compressive strengths of ICCM reach the 42.5R normal Portland cement level, and the leaching concentrations of heavy metals meet the Chinese integrated wastewater discharge standard GB 8978-1996. As predominant hydration products, ettringite, hydrocalumite and amorphous C-S-H gel are principally responsible for the strength development of ICCM, and the (Ca + Mg)/(Si + Al) ratio at 0.88 has the best polymerized structure. The heavy metals are well solidified through combining with the C-S-H gel or absorbed in the hydration pastes. This paper provides an effective solution to use the MSWI fly ash in building material. [ABSTRACT FROM AUTHOR]

Corrosion fatigue (CF) tests of 316LN weld metal were investigated in high-temperature water at different strain rates (0.0004–0.4%/s) under strain amplitude of 0.6%. Relationship between CF life and strain rate was proposed and environmental fatigue correction factor F en was also calculated. It was found that the γ/δ phase boundary was more susceptible to cracking at low strain rates and δ-ferrite worked as a barrier to retard the crack growth at high strain rates. Mechanisms of CF damage involving the effects of strain rate, hydrogen, δ-ferrite and residual strain on crack growth are also discussed. • Quantitative relation between fatigue life of 316LN weld metal and strain rate is purposed. • Effect of δ-ferrite changed with strain rate due to the interaction between localized deformation and environmental damage. • Mechanisms of CF damage involving the effects of hydrogen and residual strain on crack growth are proposed. [ABSTRACT FROM AUTHOR]

Recently, metal halide perovskite materials (CsPbX 3 , X = Cl, Br, and I) have attracted extensive attention for designing optoelectronic devices owing to their tuneable bandgap and high photoluminescence quantum yields (PLQYs). However, the corresponding study of CsPbX 3 perovskite quantum dots (QDs) with blue luminescence still lags far behind that of their red and green counterparts. Herein, we developed aluminium (Al3+) ion-doped CsPbBr 3 perovskite QDs through a supersaturated recrystallization synthetic approach at room temperature. The crystal structure and optical properties of the as-prepared QDs were systematically characterized. The results reveal that the particle size and lattice spacing of Al3+ ion-doped CsPbBr 3 QDs decrease as the Al/Pb molar ratio increases, which is attributed to the radius of Al3+ ions being much smaller than Pb2+ ions. A significant blueshift in the luminescence from 503 nm to 465 nm of Al3+ ion-doped QDs is observed as the Al/Pb molar ratio increases. Moreover, high colour purity (wide full-width at half-maximum of 83.3 meV) blue photoluminescence emission at 465 nm with a PLQY of 65.7% is achieved when the Al/Pb ratio reaches 1.0 in the Al3+ ion-doped CsPbBr 3 QDs, which shows good stability under ambient atmosphere. These as-prepared high colour purity blue luminescence Al3+ ion-doped CsPbBr 3 QDs show promising potential in blue optoelectronic fields. • A facile strategy to synthesize less-lead Al3+ ion-doped CsPbBr 3 QDs at room-temperature was proposed. • A significant blueshift from 503 nm to 465 nm of Al3+ ion-doped QDs is observed as the Al/Pb molar ratio increase. • The high colour purity blue photoluminescence emission at 465 nm with PLQY of 65.7% is achieved. [ABSTRACT FROM AUTHOR]