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1.
魏宁  刘胜男  魏凤  李小春 《环境科学》2023,44(12):6621-6629
中国水泥行业面临巨大的碳达峰与碳中和压力.CO2捕集利用与封存(CCUS)技术是能够实现化石资源低碳利用的碳减排技术.在中国水泥企业数据基础上,采用全流程CCUS系统模型(ITEAM-CCUS)评估CCUS的碳减排潜力对水泥企业碳中和非常重要.模型从源汇匹配距离、捕集率、CCUS技术和技术水平这4个方面设置了10种情景,完成了水泥行业的企业筛选、场地筛选、CCUS技术经济评估和源汇匹配,初步回答了水泥企业结合CCUS的封存场地、减排规模、成本范围和优先项目分布等关键问题.在250 km匹配距离、85%净捕集率、CO2-EWR技术和当前技术水平情景,44%的水泥企业可以利用CO2强化地下水开采(CO2-EWR)技术开展碳减排,累计年碳减排量为6.25亿t,平准化成本为290~1838元·t-1;具有全流程CO2-EWR早期示范优势的地区为新疆、内蒙古、宁夏、河南和河北等.水泥企业开展全流程CCUS项目技术可行,可以实现大规模CO2减排,低成本项目具有早期示范机会.研究结果可为水泥行业低碳发展和CCUS商业化部署提供定量参考.  相似文献   
2.
● B[a]P, nicotine and phenanthrene molecules altered the secondary structure of Aβ42. ● β-content of the peptide was significantly enhanced in the presence of the PAHs. ● Nicotine made stable cluster with Aβ42 peptide via hydrogen bonds. ● Phenanthrene due to its small size, interfered with the Aβ42 monomer more strongly. Recent studies have correlated the chronic impact of ambient environmental pollutants like polycyclic aromatic hydrocarbons (PAHs) with the progression of neurodegenerative disorders, either by using statistical data from various cities, or via tracking biomarkers during in-vivo experiments. Among different neurodegenerative disorders, PAHs are known to cause increased risk for Alzheimer’s disease, related to the development of amyloid beta (Aβ) peptide oligomers. However, the complex molecular interactions between peptide monomers and organic pollutants remains obscured. In this work, we performed an atomistic molecular dynamics study via GROMACS to investigate the structure of Aβ42 peptide monomer in the presence of benzo[a]pyrene, nicotine, and phenanthrene. Interestingly the results revealed strong hydrophobic, and hydrogen-bond based interactions between Aβ peptides and these environmental pollutants that resulted in the formation of stable intermolecular clusters. The strong interactions affected the secondary structure of the Aβ42 peptide in the presence of the organic pollutants, with almost 50 % decrease in the α-helix and 2 %–10 % increase in the β-sheets of the peptide. Overall, the undergoing changes in the secondary structure of the peptide monomer in the presence of the pollutants under the study indicates an enhanced formation of Aβ peptide oligomers, and consequent progression of Alzheimer’s disease.  相似文献   
3.
为探明固原市农田土壤中微塑料分布特征,通过现场采集调查、显微镜观察和傅里叶变换红外光谱等方法分析了固原市农田土壤中微塑料的丰度、类型、颜色、大小和外形等特征,用污染负荷指数法(PLI)评估了微塑料污染风险.结果表明,固原市农田土壤(耕作层)微塑料丰度为186.32~1286.24 n ·kg-1,设施农业土壤微塑料丰度分别较非设施农业有膜和无膜种植土壤显著增加35.56%和228.91%,耕作层微塑料丰度是犁底层的0.31倍.PE (26.42%~62.83%)和PP (27.64%~42.62%)为主要的微塑料类型,设施农业土壤微塑料种类数显著大于非设施农业.<100 μm微塑料占32.21%~42.52%,而>1000 μm只占0.28%~12.31%,耕作层微塑料粒径比犁底层高47.39%,设施农业土壤微塑料粒径最大,非设施无膜种植最小.微塑料形状主要为薄膜、纤维、碎片和微珠,其中纤维状丰度最大,薄膜状次之.共检测出7种颜色的微塑料,以白色和黑色为主.研究区污染风险总体为低风险,设施农业土壤微塑料污染风险最高.研究结果将为我国农田土壤微塑料污染评估及微塑料土壤环境行为提供数据参考.  相似文献   
4.
环境规制对资源型城市绿色全要素生产率是否具有推动作用,通过何种路径驱动以及是否存在城市类型异质性有待进一步理清。本文选取2004—2019年中国113座资源型城市的面板数据,利用非径向、非角度的SBM模型与GML指数对资源型城市绿色全要素生产率进行测算,随后通过构建多重中介效应模型实证检验了科技创新、外商直接投资和产业结构优化在环境规制影响绿色全要素生产率的传导机制及其在城市类型间的异质性。研究表明:(1)从全样本回归结果看,环境规制对资源型城市绿色全要素生产率的作用系数显著为正,产业结构优化和外商直接投资均发挥了显著的正向中介效应,而科技创新表现为间接抑制作用;在非资源型城市中,三类中介效应均不显著。(2)类型异质性检验显示,科技创新在成长型、成熟型城市中发挥了正向中介效应,在再生型城市中表现为间接抑制作用;外商直接投资在衰退型城市中的中介效应值为正,而在再生型城市中表现为负向中介效应;产业结构优化在成长型与成熟型城市中发挥了正向中介效应。(3)对比中介效应结果表明,全样本回归时,产业结构优化、外商直接投资和科技创新的中介效应梯次递减,产业结构优化的中介效应占比接近80%,环境规制的...  相似文献   
5.
Despite long-standing knowledge of the benefits of riparian buffers for mitigating nonpoint source pollution, many streams are unprotected by buffers. Even landowners who understand ecological values of buffers mow riparian vegetation to the streambank. Do trends in rural riparian conditions reflect the development of riparian forest science? What motivates residential riparian management actions? Using high-resolution orthoimagery, we quantified riparian conditions and trends between 1998 and 2015 in the rural upper Little Tennessee River basin in Macon County, North Carolina and explored how landowners view riparian zone management and riparian restoration programs. Buffer composition in 2015 was as follows: no buffer (32.5%), narrow (19.3%), forested (26.7%), shrub (7.2%), and intermediate (7.0%). Relative to 1998, the greatest decrease occurred in the no buffer class (−17.7%, 46 km) and the largest increases occurred in the shrub (+72.5%, 20 km) and narrow (12.6%, 14 km) classes. Forested buffer marginally increased. Semi-structured interview data suggest that landowners prioritize recreational and scenic aspects of riparian buffers over ecological functions such as filtration and bank stabilization. Riparian restoration programs might be made more enticing to non-adopters if outreach language appealed to landowner priorities, design elements demonstrated intentional management, and program managers highlighted areas where ecological goals and landowner values align.  相似文献   
6.
刘钰  曾妍妍  周金龙  闫志雲  白凡 《环境科学》2023,44(12):6778-6789
开展地下水污染风险评价研究是地下水污染防控的重要环节.以巴里坤-伊吾盆地平原区地下水为研究对象,构建DRSTIW模型进行地下水脆弱性评价;根据污染场地调查资料和土地利用类型划分点源和面源污染,进行地下水污染荷载评价;考虑地下水的原生价值、经济价值和生态价值进行地下水功能价值评价;利用ArcGIS的地图代数功能生成地下水污染风险评价图,采用ROC曲线验证地下水污染风险评价结果,通过计算G指数得到地下水污染风险空间冷热点分布,结合重心和标准差椭圆对热点变动情况进行定量分析.结果表明,研究区地下水污染风险整体较低,高污染风险区和较高污染风险区仅占研究区总面积的6.8%,主要位于伊吾县的淖毛湖镇、盐池镇,巴里坤县的奎苏镇、石人子乡、花园乡和兵团红山农场,该区域内地下水埋深较浅,土壤表层和包气带介质透水性能较强,吸附能力较差,加之污染源分布较集中,使得污染物易于迁移富集,在地下水高脆弱性和高污染荷载的双重作用下导致局部区域地下水污染风险升高.受人类活动影响,地下水污染风险在空间上存在一定的集聚现象,整体表现为由西北向东南演变的趋势.地下水污染风险评价结果为划分地下水污染防治区提供重要参考.  相似文献   
7.
Sectorial approach for monitoring heavy metal pollution in rivers has failed to report realistic pollution status and associated ecological and human health risks. The increasing spread of heavy metals from different sources and emerging risks to human and environmental health call for reexamining heavy metal pollution monitoring frameworks. Also, the sources, spread, and load of heavy metals in the environment have changed significantly over time, requiring consequent modification in the monitoring frameworks. Therefore, studies on heavy metal monitoring in rivers conducted in the last decade were evaluated for experimental designs, research frameworks, and data presentations. Most studies (∼99%) (i) lacked inclusiveness of all environmental compartments; (ii) focused on “one pollutant – one/two compartment” or sometimes “one pollutant – one compartment – one effect” approach; and (iii) remained “data-rich but information poor.” An ecological approach with integrative system thinking is proposed to develop a holistic approach for monitoring river pollution. It is visualized that heavy metal monitoring, risk analyses, and water management must incorporate tracking pollutants in different environmental compartments of a river (water, sediment, and floodplain/bank soil) and consider correlating it with riverbank land use. The systems-based pollution monitoring and assessment studies will reveal the critical factors that drive heavy metals pollutant movement in ecosystems and associated potential risks to the environment, wildlife, and humans. Also, water quality and pollution indexing tools would help better communicate complex pollution data and associated risks among all stakeholders. Therefore, integrating systems approaches in scientific- and policy-based tools would help sustainably manage the health of rivers, wildlife, and humans.  相似文献   
8.
Gene E. Likens 《Ambio》2021,50(2):278
Early studies published in Ambio showed large-scale acidification of lakes in southern Sweden and Norway from acid rain. These studies were important for delimiting various scientific issues and thus for eventually contributing to legislation, which reduced emissions of sulfur dioxide and nitrogen oxides and helped to mitigate this major environmental problem. Long-term studies and monitoring in Sweden and Norway and at Hubbard Brook Experimental Forest in New Hampshire helped guide this legislation in Europe and in the USA.  相似文献   
9.
The iron and steel industry is not only an important foundation of the national economy, but also the largest source of industrial air pollution. Due to the current status of emissions in the iron and steel industry, ultra-low pollutant emission control technology has been researched and developed. Liquid-phase proportion control technology has been developed for magnesian fluxed pellets, and a blast furnace smelting demonstration project has been established to use a high proportion of fluxed pellets (80%) for the first time in China to realize source emission reduction of SO2 and NOx. Based on the characteristics of high NOx concentrations and the coexistence of multiple pollutants in coke oven flue gas, low-NOx combustion coupled with multi-pollutant cooperative control technology with activated carbon was developed to achieve efficient removal of multiple pollutants and resource utilization of sulfur. Based on the characteristics of co-existing multiple pollutants in pellet flue gas, selective non-catalytic reduction (SNCR) coupled with ozone oxidation and spray drying adsorption (SDA) was developed, which significantly reduces the operating cost of the system. In the light of the high humidity and high alkalinity in flue gas, filter materials with high humidity resistance and corrosion resistance were manufactured, and an integrated pre-charged bag dust collector device was developed, which realized ultra-low emission of fine particles and reduced filtration resistance and energy consumption in the system. Through source emission reduction, process control and end-treatment technologies, five demonstration projects were built, providing a full set of technical solutions for ultra-low emissions of dust, SO2, NOx, SO3, mercury and other pollutants, and offering technical support for the green development of the iron and steel industry.  相似文献   
10.
Ce1-xZrxO2 composite oxides (molar, x = 0-1.0, interval of 0.2) were prepared by a cetyltrimethylammonium bromide-assisted precipitation method. The enhancement of silver-species modification and catalytic mechanism of adsorption-transformation-desorption process were investigated over the Ag-impregnated catalysts for low-temperature selective catalytic oxidation of ammonia (NH3-SCO). The optimal 5 wt.% Ag/Ce0.6Zr0.4O2 catalyst presented good NH3-SCO performance with >90% NH3 conversion at temperature (T) ≥ 250°C and 89% N2 selectivity. Despite the irregular block shape and underdeveloped specific surface area (∼60 m2/g), the naked and Ag-modified Ce0.6Zr0.4O2 solid solution still obtained highly dispersed distribution of surface elements analyzed by scanning electron microscope-energy dispersive spectrometer (SEM-EDS) (mapping), N2 adsorption-desorption test and X-ray diffraction (XRD). H2 temperature programmed reduction (H2-TPR) and X-ray photoelectron spectroscopy (XPS) results indicated that Ag-modification enhanced the mobility and activation of oxygen-species leading to a promotion on CeO2 reducibility and synergistic Ag0/Ag+ and Ce4+/Ce3+ redox cycles. Besides, Ag+/Ag2O clusters could facilitate the formation of surface oxygen vacancies that was beneficial to the adsorption and activation of ammonia. NH3-temperature programmed desorption (NH3-TPD) showed more adsorption-desorption capacity to ammonia were provided by physical, weak- and medium-strong acid sites. Diffused reflectance infrared Fourier transform spectroscopy (DRIFTS) experiments revealed the activation of ammonia might be the control step of NH3-SCO procedure, during which NH3 dehydrogenation derived from NHx-species and also internal selective catalytic reduction (i-SCR) reactions were proposed.  相似文献   
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