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191.
总结了混凝土结构加固的原因、方法,对主要方法的优缺点进行了阐述,提出了目前混凝土结构加固亟待解决的问题。 相似文献
192.
汽车涂装车间常用活性炭和沸石转轮作为喷漆室废气处理方式,活性炭吸附设备处理能力大,性能可靠;沸石转轮处理效率高,吸附效果好.针对这2种常用的处理方案进行具体分析和介绍.重点介绍了2种方案各自不同的应用场景,不同应用特点及处理效率.2种废气处理方案均有实际项目运用,结合实际案例进行计算后,总结出了2种处理方案的优缺点以及... 相似文献
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在双碳战略的重大战略部署下,对轨道交通全生命周期碳排放进行研究,合理量化其碳排放水平是实现交通部门碳达峰、碳中和的重要措施。本文基于北京某新建地铁线路,对轨道交通全生命周期碳排放进行分析,建立了轨道交通全线、全生命周期的碳排放计算模型,并定量计算新建地铁线路全线、全生命周期的碳排放量。同时,对建设阶段和运营阶段的降碳措施做出分析,定量评估其降碳潜力。对全长81 km新建地铁线路进行碳排放量计算,得到建设阶段碳排放量为257万t CO2eq,运营阶段为5.35万t CO2eq/a,50年运营周期总计碳排放量524万t CO2eq。建设阶段使用可再生材料及预制结构可减少碳排放量7%;运营阶段综合采用多种节能降碳措施后,可降碳27%;50年运营周期降碳潜力总计17%。该模型的建立对城轨交通全生命周期碳排放定量计算有指导意义,降碳措施的研究成果以期为城轨交通完成绿色低碳转型、实现交通部门碳达峰、碳中和提供参考。 相似文献
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Rising population, income and urbanization are increasing urban passenger transport demand in India. Energy and emissions intensities associated with conventional transport are no longer sustainable vis-a-vis energy security, air quality and climate change. Cities are seeking transport roadmaps that jointly mitigate these risks. Roadmaps vary across cities, but approach to delineate actions is common: (i) ‘representative vision’ that articulates long-term goals, (ii) methods for comparative scenarios assessment, and (iii) quantification of co-benefits to prioritize actions. This paper illustrates application of quantitative modeling to assess development and environmental co-benefits for Ahmedabad city. The paper constructs two transport scenarios spanning till 2035. The bifurcating themes are: (i) Business-as-Usual (BAU) and Low Carbon Scenario (LCS). The quantitative assessment using Extended Snapshot (ExSS) Model shows that transport activity shall result in four-fold increase in energy demand under BAU from 2010 to 2035. Three key contributors to CO2 mitigation under LCS in merit order are: (i) fuel switch, including decarbonized electricity, (ii) modal shift, and (iii) substitution of travel demand. Scenarios analysis shows that LCS improves energy security by reducing oil demand and also delivers air quality co-benefits – reducing 74% NOx and 83% PM2.5 from the passenger transport sector compared to BAU in 2035. Finally, the paper argues that cities in developing countries can leverage carbon finance to develop sustainable and low carbon mobility plans that prevent adverse infrastructure and behavioral lock-ins and prompt low carbon development. 相似文献
198.
Phytoplankton, bacteria and microzooplankton were investigated on a transect in the Bellingshausen Sea during the ice melt period in November–December 1992. The transect along the 85°W meridian comprised seven stations that progressed from solid pack-ice (70°S), through melting ice into open water (67°S). The abundance, biomass and taxonomic composition were determined for each component of the microbial community. The phytoplankton was mostly dominated by diatoms, particularly small (<20 μm) species. Diatom abundance ranged from 66 000 cells l−1 under the ice to 410 000 cells l−1 in open water. Phytoplankton biomass varied from <1 to 167 mg C m−3, with diatoms comprising 89–95% of the total biomass in open water and autotrophic nanoflagellates comprising 57% under the ice. The standing stocks of autotrophs in the mixed layer ranged from 95 mg C m−2 under the pack-ice to 9478 mg C m−2 in open waters. Bacterial abundance in ice-covered and open water stations varied from 1.1 to 5.5×108 cells l−1. Bacterial biomass ranged from 2.4 mg C m−3 under pack-ice to an average of 14 mg C m−3 in open water. The microzooplankton consisted mainly of aloricate oligotrich ciliates and heterotrophic dinoflagellates and these were most abundant in open waters. Their biomass varied between 0.2 and 54 mg C m−3 with a minimum at depth under the ice and maximum in open surface waters. Microheterotrophic standing stocks varied between 396 mg C m−2 under pack-ice and 3677 mg C m−2 in the open waters. The standing stocks of the total microbial community increased consistently from 491 mg C m−2 at the ice station to 13 155 mg C m−2 in open waters, reflecting the productive response of the community to ice-melt. The composition of the microbial community also shifted markedly from one dominated by heterotrophs (82% of microbial stocks) at the ice station to one dominated by autotrophs (73% of microbial stocks) in the open water. Our estimates suggest that the microbial community comprised >100% of the total particulate organic carbon (POC) under the ice and 62–66% of the measured POC in the open waters. 相似文献
199.
陆缙华 《电力机车与城轨车辆》2001,24(3):16-17,29
通过对广州地铁一号线车辆运行中闸瓦、车轮及受电弓碳滑板的磨损量分析,确认广州地铁一号线车辆选用交流传动、轮轨参数及弓网参数等关键技术的正确和合理性及由此获得的良好性能。 相似文献
200.