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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]

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]

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]