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1.
When accounting the CO2 emissions responsibility of the electricity sector at the provincial level in China,it is of great significance to consider the scope of both producers’ and the consumers’ responsibility,since this will promote fairness in defining emission responsibility and enhance cooperation in emission reduction among provinces.This paper proposes a new method for calculating carbon emissions from the power sector at the provincial level based on the shared responsibility principle and taking into account interregional power exchange.This method can not only be used to account the emission responsibility shared by both the electricity production side and the consumption side,but it is also applicable for calculating the corresponding emission responsibility undertaken by those provinces with net electricity outflow and inflow.This method has been used to account for the carbon emissions responsibilities of the power sector at the provincial level in China since 2011.The empirical results indicate that compared with the production-based accounting method,the carbon emissions of major power-generation provinces in China calculated by the shared responsibility accounting method are reduced by at least 10%,but those of other power-consumption provinces are increased by 20% or more.Secondly,based on the principle of shared responsibility accounting,Inner Mongolia has the highest carbon emissions from the power sector while Hainan has the lowest.Thirdly,four provinces,including Inner Mongolia,Shanxi,Hubei and Anhui,have the highest carbon emissions from net electricity outflow- 14 million t in 2011,accounting for 74.42% of total carbon emissions from net electricity outflow in China.Six provinces,including Hebei,Beijing,Guangdong,Liaoning,Shandong,and Jiangsu,have the highest carbon emissions from net electricity inflow- 11 million t in 2011,accounting for 71.44% of total carbon emissions from net electricity inflow in China.Lastly,this paper has estimated the emission factors of electricity consumption at the provincial level,which can avoid repeated calculations when accounting the emission responsibility of power consumption terminals(e.g.construction,automobile manufacturing and other industries).In addition,these emission factors can also be used to account the emission responsibilities of provincial power grids.  相似文献   
2.
采用玉米芯为碳源,聚乙烯醇(PVA)为包埋载体,饱和硼酸(H3BO3)为交联剂,研究了硫酸盐还原菌污泥(SRBS)、铁屑、麦饭石共固处理合成煤矿酸性废水的最优配比与机理,并分析了固定化过程中小球稳定性及活性的变化规律。实验结果表明,SRBS投加量是影响处理效果的最显著因子,当投加30%SRBS、2%铁屑、3%麦饭石时SO2-4、Mn2+去除率分别为94.13%和84.39%,溶液p H为7.03,未检测出Fe2+;随着交联时间的延长,小球膨胀率及SO2-4还原率分别呈线性与指数下降,从保持小球稳定性与活性角度考虑,可将交联时间设定为4~8 h;该法可为市政污泥的处置以及生物法处理煤矿酸性废水的工程应用提供技术参考。  相似文献   
3.
针对传统Fenton体系Fe(Ⅲ)累积和pH适用范围过窄等缺点,采用羟胺(HA)强化的HA-Fenton体系,以对氯苯酚(4-CP)为目标污染物进行降解实验,考察了Fe(Ⅱ)投加量、H2O2投加量、HA投加量和溶液pH等工艺条件对4-CP去除率的影响。实验结果表明:HA-Fenton体系适用于酸性和弱酸性条件,最佳pH范围为3.0~4.0;在溶液pH为3.0、Fe(Ⅱ)投加量为5.0 μmol/L、H2O2投加量为0.4 mmol/L、HA投加量为0.20 mmol/L的最适条件下,反应10 min, 4-CP去除率达64.25 %。  相似文献   
4.
采用液相催化氧化NO_x的方法,通过磷矿浆中过渡金属离子的催化作用,达到净化电厂烟气中NO的目的。考察了烟气含氧量、吸收温度、磷矿浆固液比及气体流量对磷矿浆湿法脱硝的影响。结果表明,试验最佳条件为NO进口质量浓度670 mg/m~3、磷矿浆吸收温度25℃、固液比500 g/L、流量0.3 L/min、含氧量20%;优化条件下的磷矿浆脱除效率最高可达88.9%。随着磷矿浆湿法催化氧化脱硝反应的进行,p H值不断下降,导致磷矿浆逐渐失效,需补入新鲜矿浆,维持吸收液的p H值以保证良好脱硝率。  相似文献   
5.
洞庭湖水情受到长江和四水的综合影响,因此三峡水库蓄水运行必将对洞庭湖出口水位产生影响。通过构建模型对洞庭湖出口的水位过程进行模拟,以三峡出库日均流量、洞庭湖四水合成日均流量为输入,城陵矶站日水位过程为输出,以量化和分析城陵矶水位变化受三峡水库调度的影响。通过三峡入库流量代替出库流量,还原自然状态下的水位过程,并根据各调度方案计算的出库流量模拟各调度方案下城陵矶的水位变化过程。对比各调度方案下三峡水库蓄泄水对洞庭湖出口水位的影响可以发现:各蓄水方案对洞庭湖出口水位都造成了一定的影响,起蓄时间较早的方案影响时间较长,整体上平均水位变化也较大,但起蓄后水位变化较为平缓;起蓄时间较晚的方案影响时间较短,整体上平均水位变化相对较小,但起蓄后水位变化较为剧烈。考虑到不同年份和不同来水类型情况对洞庭湖出口水位的影响存在差异,各蓄水方案的优劣需要具体分析和讨论  相似文献   
6.
7.

As a global pollutant, Hg (Hg) since the turn of the last century has received increased attention. Decreasing the emission of Hg into the food chain and the atmosphere is an effective way to reduce the Hg damage. The current study provided information about pilot-scale horizontal subsurface flow (HSSF) constructed wetlands (CWs) to remove different Hg species in polluted water. Synthetic wastewater was fed to two HSSF CWs, one was planted with Acorus calamus L and the other was unplanted as a control. The total Hg (THg), dissolved Hg (DHg), and particulate Hg (PHg) from five sites along the HSSF CWs were analyzed to describe the process of Hg removal. Results show that the CWs have high removal efficiency of Hg which is more than 90%. The removal efficiencies of THg and DHg from the unplanted CW were 92.1?±?3.6% and 72.4?±?13.1%, respectively. While, the removal efficiencies of THg and DHg in planted CW were 95.9?±?7.5% and 94.9?±?4.9%, which were higher than that in blank CW. The PHg was mainly removed in the first quarter of the CWs, which was also revealed by the partition coefficient Kd. To a certain extent, the effect of plants depends on the hydraulic retention time (HRT). The results in the current study show the potential of the HSSF-CWs for restoration from Hg-contaminated water.

  相似文献   
8.
Fu  Li  Chen  Yi  Yang  Xinyi  Yang  Zuyao  Liu  Sha  Pei  Lei  Feng  Baixiang  Cao  Ganxiang  Liu  Xin  Lin  Hualiang  Li  Xing  Ye  Yufeng  Zhang  Bo  Sun  Jiufeng  Xu  Xiaojun  Liu  Tao  Ma  Wenjun 《Environmental science and pollution research international》2019,26(20):20137-20147
Environmental Science and Pollution Research - Fetal growth has been demonstrated to be an important predictor of perinatal and postnatal health. Although the effects of maternal exposure to air...  相似文献   
9.

The purposes of this research are to quantify the concentration of heavy metals (Zn, Cu, As, Pb, Cd, and Hg) in the water and fish tissues of common carp (Cyprinus carpio) in the upper Mekong River and to thereby elucidate the potential dietary health risks from fish consumption of local residents. Surface water and fish tissues (gill, muscle, liver, and intestine) from four representative sample areas (influence by a cascade of four dams) along the river were analyzed for heavy metal concentrations. Results revealed that the levels of heavy metals in fish were tissue-dependent. The highest Cu and As levels were found in the liver; the highest Zn and Pb levels occurred in the intestine, and the highest Hg level was found in the muscle. The total target hazard quotient (THQ) value for residents is > 1 for long-term fish consumption, and local residents are, therefore, exposed to a significant health risk. Results from the current study provide an overall understanding of the spatial and tissue distribution of heavy metals in water and fish body along the upper Mekong River under the influence of cascade dams and highlight the potential health risk of As for the local residents of long-term fish consumption.

  相似文献   
10.
• Air masses from Zhejiang Province is the major source of O3 in suburban Shanghai. • O3 formation was in VOC-sensitive regime in rural Shanghai. • O3 formation was most sensitive to propylene in rural Shanghai. A high level of ozone (O3) is frequently observed in the suburbs of Shanghai, the reason for this high level remains unclear. To obtain a detailed insight on the high level of O3 during summer in Shanghai, O3 and its precursors were measured at a suburban site in Shanghai from July 1, 2016 to July 31, 2016. Using the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model and concentration weighted trajectories (CWT), we found that Zhejiang province was the main potential source of O3 in suburban Shanghai. When the sampling site was controlled by south-western winds exceeding 2 m/s, the O3-rich air masses from upwind regions (such as Zhejiang province) could be transported to the suburban Shanghai. The propylene-equivalent concentration (PEC) and ozone formation potential (OFP) were further calculated for each VOC species, and the results suggested that propylene, (m+p)-xylene, and toluene played dominant roles in O3 formation. The Ozone Isopleth Plotting Research (OZIPR) model was used to reveal the impact of O3 precursors on O3 formation, and 4 base-cases were selected to adjust the model simulation. An average disparity of 18.20% was achieved between the simulated and observed O3 concentrations. The O3 isopleth diagram illustrated that O3 formation in July 2016 was in VOC-sensitive regime, although the VOC/NOx ratio was greater than 20. By introducing sensitivity (S), a sensitivity analysis was performed for O3 formation. We found that O3 formation was sensitive to propylene, (m+p)-xylene, o-xylene and toluene. The results provide theoretical support for O3 pollution treatment in Shanghai.  相似文献   
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