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Evaluating the effect of the carbon emissions trading scheme (ETS) on the decarbonization of the power sector is a basic task in the construction of China’s ETS. We use the energy flow relationship between the power and heat sectors to develop a more accurate accounting framework for CO2 emissions in the power sector and employ the difference-in-differences method to evaluate the impact of China’s ETS on CO2 emissions in the power sector and its dynamic effect. On this basis, we explore the mechanisms by which the ETS facilitates the decarbonization of the power sector, as well as its heterogeneous impacts. We find that the ETS has significantly promoted the decarbonization of the power sector, reducing its CO2 emissions in the pilot provinces by approximately 24.53 Mt compared to the non-pilot provinces. The decarbonization effect of the ETS was continuous and strengthened. In addition, the ETS promotes decarbonization of the power sector through technological advances in power generation and electricity utilization. Finally, the ETS’s decarbonization effect on the power sector is influenced by the heterogeneity of regions, carbon prices and quota allocation methods. Our findings have beneficial implications for the construction of carbon markets in the context of carbon neutralisation and carbon peaking. [ABSTRACT FROM AUTHOR]

The ability of composite cement materials to resist erosion by chloride ions is a critical factor in evaluating their dependability. This study aims to examine the influence of graphene oxide on the transportation of water molecules and chloride ions in modified cement composites. Molecular dynamics analysis suggests that graphene oxide can effectively bond to the substrate of hydrated calcium silicate gel pores, which forms a stronger confined fluid zone under the action of electrostatic interactions and van der Waals forces. Graphene oxide has negatively charged oxygen functional groups on its surface, and within a certain size range, it becomes more effective at restricting the penetration of water molecules and chloride ions. In addition, chloride solution immersion experiments were performed on graphene oxide modified cement mortar. The results demonstrated that a small quantity of graphene oxide can significantly improve the resistance of modified cement mortar to chloride ion erosion, whereas excessive amounts are detrimental, which aligns with the simulation results. It is hoped that this study will provide valuable insights into the use of graphene oxide nanoparticles in the corrosion protection of cement composites. [ABSTRACT FROM AUTHOR]

Graphene-based materials have been considered as reinforcement for cement-based materials due to its excellent properties. In this paper, the effects of graphene oxide (GO) and graphene nanoplatelets (GNPs) on the mechanical properties and microstructure of cement-based composites are investigated. The results reveal that the incorporation of 0.02 wt% GO and GNPs can enhance the flexural strength by 16.3% and 11.6%, respectively. In addition, GO and GNPs can fill the cracks and form a compacted microstructure in cement mortars. Furthermore, the enhanced mechanism of calcium silicate hydrate composite (C–S–H), which is the main production of cement hydration, is studied by reaction molecular dynamics. The results from simulation show that Young's modulus and tensile strength of C–S–H are enhanced by 32.1% and 23.8% with the incorporation of GO, because the hydrogen-bonds (H-bonds) linkages and Ca2+ near the interface surface play an important role to improve the interface adhesion and transfer more loads between GO and C–S–H. Comparatively, the graphene nanosheet unremarkable enhances the mechanical behaviour of C–S–H composite due to poor binding in the interlayer region. [ABSTRACT FROM AUTHOR]

As a form of pollution source control and a low-impact development measure, bioretention is a convenient, economical, and effective method for the removal of heavy metals from stormwater runoff, which can adapt to the randomness and uncontrollability of non-point source pollution. However, few studies have assessed the performance of bioretention in the simultaneous removal of multiple heavy metals and the impact of heavy metal migration on the bioretention life cycle. In this study, the removal rates of various heavy metals: copper (Cu), zinc (Zn), lead (Pb), and cadmium (Cd), were enhanced using a biochar modified bioretention cell, as compared to the traditional sandy soil bioretention process. Following treatment with the biochar modified bioretention cell, the average concentrations of Cu, Zn, Pb, and Cd were 55%, 61%, 19.66%, and 36.43% lower than the traditional sandy soil bioretention effluent, respectively. These results show that biochar significantly improves the removal of heavy metals by the bioretention process, especially Cu and Zn. This study also evaluated the effect of biochar on the inhibition of heavy metal migration in the filler material, by sampling and analysing the filler and retained water at different filler depths, then repeating the filler leaching experiment after simulated rainfall. The content of heavy metals at a filler depth of 45 cm in the traditional sandy soil bioretention system, was significantly higher than in the biochar modified bioretention system, showing that biochar plays an important role in the inhibition of heavy metal migration. [ABSTRACT FROM AUTHOR]