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711.
在一台六缸四冲程高压共轨柴油机上开展了乙醇/聚甲氧基二甲醚(PODE)/柴油混合燃料对内燃机燃烧和排放影响的试验研究.结果表明,在转速为1137 r·min-1,转矩为735 N·m的工况条件下,随着掺混PODE和乙醇比例的增大,双峰放热越来越明显,扩散燃烧速率增大,有效燃油消耗率增大,有效热效率降低,但降低幅度小于1%,其中,DPE5(PODE体积分数为20%,乙醇体积分数为5%)的有效热效率与D100(纯柴油)基本相当.提前主喷时刻、增大喷油压力均使有效热效率增大,CO和碳烟排放降低,NOx排放增大,而对降低HC排放的影响较小.相比D100,混合燃料可降低CO、HC、碳烟排放,在低喷油压力和较晚主喷时刻下,对碳烟的减排效果更为显著,最大降幅分别为85.5%(主喷时刻-1℃ A ATDC、喷油压力900 bar)和82.9%(主喷时刻-3℃ A ATDC、喷油压力600 bar),但不同混合燃料间的排放差异较小.综上所述,重型柴油机使用乙醇/PODE/柴油混合燃料可在热效率相当的前提下对排放有较大改善. 相似文献
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选取灵活的单区域模型,运用实物产值比计算方法,选取日本为进口代表国并结合进口国GDP排放强度的修正方法,针对加工贸易产品占我国外贸总额约50%的特点,改进现有内涵排放测算方法.研究结果显示我国出口产品内涵排放得到了显著的改善,呈现碳排放与出口额脱钩的现象,进口产品内涵排放占比全国碳排放的比重维持在3~5%左右,“十二五”期间净出口内涵排放的总量和占比比“十一五”期间都有所降低,显示我国出口贸易政策调整作用正在显现.需要不断坚持优化进出口政策,尽早实现我国进出口产品内涵排放之间的平衡.投资增速的快速下降已经开始对产业结构产生影响,但中国未来需要进一步加速最终消费的增长以弥补投资下降所带来的需求不足,并鼓励服务业需求的发展. 相似文献
713.
基于LMDI(Logarithmic Mean Divisia Index Method)方法分析2001-2016年京津冀地区电力部门CO2排放的8个影响因素,考虑了京津冀地区电力部门从生产投入、转换、传输到消费的整个过程;并分析了2001-2016年影响京、津、冀各地区CO2排放的各因素贡献值。结果表明,1)2001-2016年京津冀地区电力部门CO2排放总体呈现递增趋势,2012年出现负增长;河北省电力部门对京津冀电力部门CO2排放贡献最大,2001-2016年累计CO2排放变化量为145.70 Mt,但河北省电力部门的减排潜力巨大;2)人均GDP效应和人口规模效应是促进京津冀地区电力部门CO2排放增长的主要因素,2001-2016年累计贡献值分别为261.86 Mt和36.47 Mt;3)用电效率效应和电力输入输出效应是京津冀地区电力部门CO2排放量增长的主要抑制作用,2001-2016年累计贡献值分别为-49.40 Mt和-47.93 Mt;4)造成京、津、冀电力部门CO2排放差异的主要因素是人均GDP、化石能源转换效率和用电效率。 相似文献
714.
Road dust is one of the most common pollutants and causes a series of negative effects on plant physiology. Dust's impacts on plants can be regarded as a combination of load,composition and grain size impacts on plants; however, there is a lack of integrated dust effect studies involving these three aspects. In our study, Sophora japonica seedlings were artificially dusted with road dust collected from the road surface of Beijing so that we could study the impacts of this dust on nitrogen/carbon allocation, biomass allocation and photosynthetic pigments from the three aspects of composition, load and grain size. The results showed that the growth characteristics of S. japonica seedlings were mostly influenced by dust composition and load. Leaf N, root–shoot ratio and chlorophyll a/b were significantly affected by dust composition and load; leaf C/N, shoot biomass, total chlorophyll and carotenoid were significantly affected by dust load; stem N and stem C/N were significantly affected by dust composition; while the dust grain size alone did not affect any of the growth characteristics. Road dust did influence the growth characteristics more extensively than loam. Therefore, a higher dust load could increase the differences between road dust and loam treatments. The elements in dust are well correlated to the shoot N, shoot C/N, and root–shoot ratio of S. japonica seedlings. This knowledge could benefit the management of urban green spaces. 相似文献
715.
Vehicular emissions in China in 2006 and 2010 were calculated at a high spatial resolution based on the data released by the National Bureau of Statistics, by taking the emission standards into consideration. China's vehicular emissions of carbon monoxide(CO),nitrogen oxides(NO_x), volatile organic compounds(VOCs), ammonia(NH_3), fine particulate matters(PM_(2.5)), inhalable particulate matters(PM_(10)), black carbon(BC), and organic carbon(OC) were 30,113.9, 4593.7, 6838.0, 20.9, 400.2, 430.5, 285.6, and 105.1 Gg, respectively, in 2006 and 34,175.2, 5167.5, 7029.4, 74.0, 386.4, 417.1, 270.9, and 106.2 Gg, respectively, in 2010. CO,VOCs, and NH_3 emissions were mainly from motorcycles and light-duty gasoline vehicles,whereas NO_X, PM_(2.5), PM_(10), and BC emissions were mainly from rural vehicles and heavyduty diesel trucks. OC emissions were mainly from motorcycles and heavy-duty diesel trucks. Vehicles of pre-China Ⅰ(vehicular emission standard of China before phase Ⅰ) and China Ⅰ(vehicular emission standard of China in phase Ⅰ) were the primary contributors to all of the pollutant emissions except NH_3, which was mainly from China Ⅲ and China Ⅳ gasoline vehicles. The total emissions of all the pollutants except NH_3 changed little from2006 to 2010. This finding can be attributed to the implementation of strict emission standards and to improvements in oil quality. 相似文献
716.
E.D.Vicente L.A.C.Tarelho E.R.Teixeira M.Duarte T.Nunes C.Colombi V.Gianelle G.O.da Rocha A.Sanchez de la Campa C.A.Alves 《环境科学学报(英文版)》2016,28(4):246-258
Interest in renewable energy sources has increased in recent years due to environmental concerns about global warming and air pollution,reduced costs and improved efficiency of technologies.Under the European Union(EU)energy directive,biomass is a suitable renewable source.The aim of this study was to experimentally quantify and characterize the emission of particulate matter(PM_(2.5))resulting from the combustion of two biomass fuels(chipped residual biomass from pine and eucalypt),in a pilot-scale bubbling fluidized bed(BFB)combustor under distinct operating conditions.The variables evaluated were the stoichiometry and,in the case of eucalypt,the leaching of the fuel.The CO and PM_(2.5)emission factors were lower when the stoichiometry used in the experiments was higher(0.33±0.1 g CO/kg and 16.8±1.0 mg PM_(2.5)/kg,dry gases).The treatment of the fuel by leaching before its combustion has shown to promote higher PM_(2.5)emissions(55.2±2.5 mg/kg,as burned).Organic and elemental carbon represented 3.1 to 30 wt.% of the particle mass,while carbonate(CO_3~(2-))accounted for between 2.3 and 8.5 wt.%.The particulate mass was mainly composed of inorganic matter(71% to 86% of the PM_(2.5)mass).Compared to residential stoves,BFB combustion generated very high mass fractions of inorganic elements.Chloride was the water soluble ion in higher concentration in the PM_(2.5)emitted by the combustion of eucalypt,while calcium was the dominant water soluble ion in the case of pine. 相似文献
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720.
碳交易为煤层气利用提供了一条重要的市场化融资渠道。目前国际、国内碳市场均只有1个方法学适用于煤层气利用项目。我国共注册了84个煤层气利用CDM项目,年减排量3 577万t(CO_2当量),已有40个项目获得了3 767万t(CO_2当量)减排量的签发,山西占最大比例。宁夏有4座煤层气发电站开展了碳交易工作,其中3个CDM项目实现了134.1万t(CO_2当量)交易。建议依托国际、国内碳市场,从加强政府引导、整体规划布局、探索规划类碳交易等4个方面促进宁夏煤层气的利用。 相似文献