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831.
大清河-白洋淀流域生态功能评价及分区初探   总被引:1,自引:0,他引:1  
基于生态系统服务功能对流域生态环境进行功能分区是流域生态环境保护与修复的重要基础.本研究使用InVEST模型,对大清河-白洋淀流域2010、2015及2018年的生境质量、碳储量及土壤侵蚀等生态系统服务功能进行评价.结果 表明:2010-2015年流域生态环境相对稳定;2015-2018年生境质量提升,土壤侵蚀缓解,但...  相似文献   
832.
Environmental Science and Pollution Research - The spatiotemporal distribution and characterization of aerosol optical properties in the north of Vietnam were investigated extensively using the...  相似文献   
833.
Environmental Science and Pollution Research - Dissolved organic matter (DOM) and microbes are key in the planetary carbon cycle, and research on them can lead to a better understanding of the...  相似文献   
834.
Environmental Science and Pollution Research - The crop water relationship quantification is conducive to decision-making for regional food safety and resource conservation. However, irrigation...  相似文献   
835.
• The optimum SCR activity was realized by tuning the acid pretreatment. • Optimized catalysts showed NOx conversion above 90%. • The NH3 and NO adsorption capacity of Al-O3-Fe is stronger than Fe-O3-Fe. • The formation of almandine consumes Fe3+ and Al3+ and weakens their interaction. Red mud (RM), as an alkaline waste, was recently proved to be a promising substitute for the SCR catalyst. Dealkalization could improve the acidity and reducibility of red mud, which were critical for SCR reaction. However, the dealkalization effect depended on the reaction between acid solution and red mud. In this study, we realized the directional control of the chemical state of active sites through tuning the acid pretreatment (dealkalization) process. The pretreatment endpoint was controlled at pH values of 3–5 with diluted nitric acid. When the pH values of red mud were 3 and 5 (CRM-3 and CRM-5), activated catalysts showed NOx conversion above 90% at 275°C–475°C. The high initial reaction rate, Ce3+/(Ce3+ + Ce4+) ratio, and surface acidity accounted for the excellent SCR performance of CRM-5 catalyst. Meanwhile, more Fe3+ on the CRM-3 surface improved the NH3 adsorption. There was a strong interaction between Al and Fe in both CRM-5 and CRM-3 catalysts. DFT results showed that the adsorption capacity of the Al-O3-Fe for NH3 and NO is stronger than that of Fe-O3-Fe, which enhanced the NOx conversion of the catalyst. However, the almandine was formed in CRM-4, consumed part of Fe3+ and Al3+, and the interaction between Al and Fe was weakened. Also, deposited almandine on the catalyst surface covered the active sites, thus leading to lower NH3-SCR activity.  相似文献   
836.
Environmental Science and Pollution Research - This study investigated the seasonal variations of the ground-based PM2.5 concentration measured at an urban site and Terra MODIS satellite-based...  相似文献   
837.
Environmental Science and Pollution Research - Freeze–thaw (F/T) and electrochemistry both are environment-friendly and efficient sludge treatment technologies. In this study, the sludge...  相似文献   
838.
Environmental Science and Pollution Research - As a kind of solid waste with a high silicon content, electrolytic manganese residue (EMR) can be utilized as silicon source by plants through...  相似文献   
839.
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