China contributes 23 % of global carbon emissions, of which 26 % originate from the household sector. Due to vast variations in both climatic conditions and the affordability and accessibility of fuels, household carbon emissions (HCEs) differ significantly across China. This study compares HCEs (per person) from urban and rural regions in northern China with their counterparts in southern China. Annual macroeconomic data for the study period 2005 to 2012 were obtained from Chinese government sources, whereas the direct HCEs for different types of fossil fuels were obtained using the IPCC reference approach, and indirect HCEs were calculated by input-output analysis. Results suggest that HCEs from urban areas are higher than those from rural areas. Regardless of the regions, there is a similarity in per person HCEs in urban areas, but the rural areas of northern China had significantly higher HCEs than those from southern China. The reasons for the similarity between urban areas and differences between rural areas and the percentage share of direct and indirect HCEs from different sources are discussed. Similarly, the reasons and solutions to why decarbonising policies are working in urban areas but not in rural areas are discussed.
Environmental Science and Pollution Research - Morphological effect of bismuth vanadate (BiVO4) on visible light-driven catalytic degradation of aqueous paracetamol was carefully investigated using... 相似文献
Failure of steam-side oxide scales in high temperature components of boilers such as superheater and reheater tubes has significant effect on the safety of thermal power plants. Taking into account the influence that temperature has on physical properties of metal substrate and oxide scale, transient heat transfer model as well as multi-layered hollow cylinder stress model is successively developed in this work. Employing the Advanced Oxide Scale Failure Diagram (AOSFD) as failure criterion, a systematic analysis model for the failure behavior of steam-side oxide scales in T92 superheater tubes during unsteady thermal processes is established. Focusing on different steam temperature variation processes, the effects of steam-side oxide scale thickness as well as different steam temperature variation modes and variation durations on oxide scale failure issues have been analyzed. Besides, critical steam temperature drops leading to failure of oxide scales when steam temperature decreases linearly have also been investigated. Based on the analysis results, feasible measures such as selecting reasonable steam temperature variation mode and appropriately lengthening variation duration are subsequently proposed. The analysis results as well as the suggested measures in this work can provide valuable guidance for the solution of steam-side oxide scale failure issues in thermal power plants. 相似文献
ABSTRACTThis paper interrogates the impact of policy events on the efficiency of carbon market in China. The analysis covers five piloting emission trading schemes (Beijing, Shanghai, Guangdong, Shenzhen and Hubei), particularly focusing on Guangdong pilot for its weak form efficiency and the richness of policy events. Twenty-five policy events between 2014 and 2016 are categorized into seven groups. The efficiency test indicates that only Guangdong ETS has reached weak form efficiency. After exploring the policy events occurred in Guangdong ETS, it finds that although a clear long-term climate policy has been set up over the country, China’s carbon market still has a conservative risk appetite and its governing institutions still needs further development. The policy makers need to be aware of and avoid the negative impacts of policy events to the market evolvement, by introducing effective consultancy process with the stakeholders and nurturing market expectations in the long run. We also find that events like allowance auctions have considerably less impacts than previously expected and argue that auction approach should be considered a preferable option over a free allocation system in the future policy design. 相似文献
The objective of this study was to investigate the nitritation performance in a biofilm reactor for treating domestic wastewater.The reactor was operated in continuous feed mode from phases 1 to 3.The dissolved oxygen(DO)was controlled at 3.5–7 mg/L throughout the experiment.The biofilm reactor showed excellent nitritation performance after the inoculation of nitrifying sludge,with the hydraulic retention time being reduced from 24 to 7 hr.Above 90%nitrite accumulation ratio(NAR)was maintained in phase 1.Afterwards,nitratation occurred with the low NH_4~+–N concentration in the reactor.The improvement of NH_4~+–N concentration to 20–35 mg/L had a limited effect on the recovery of nitritation.However,nitritation recovered rapidly when sequencing batch feed mode was adopted in phase 4,with the effluent NH_4~+-N concentration above 7 mg/L.The improvement of ammonia oxidizing bacteria(AOB)activity and the combined inhibition effect of free ammonia(FA)and free nitrous acid(FNA)on the nitrite oxidizing bacteria(NOB)were two key factors for the rapid recovery of nitritation.Sludge activity was obtained in batch tests.The results of batch tests had a good relationship with the long term operation performance of the biofilm reactor. 相似文献