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671.
绿色低碳背景下中国产业结构调整分析 总被引:1,自引:0,他引:1
中国作为世界第一的一次能源消费国以及最大的二氧化碳排放国,在巴黎世界气候大会上承诺于2030年以前单位碳强度较2005年降低60%—65%;此外,在《"十三五"规划纲要》中中国政府也明确提出,在"十三五"时期,碳排放强度较2005年基础上降低40%—45%的目标。在此背景下,本文基于最新的投入产出表构建了产业结构优化模型。通过行业的生产结构矩阵,构建出行业的能源结构消耗矩阵及碳排结构矩阵,旨在能源消耗量与二氧化碳排放量的双重约束下,得到中国2020年最优的产业结构调整方案,并计算了基于现有科技水平下中国最大的碳排潜力。线性规划的结果显示:(1)中国2020年最优的产业结构调整方案可以满足国民经济总产出量最大化的目标,年均增长约为8%;且相比目标年份(2005年)二氧化碳强度下降46.93%,能源强度下降26.04%,达到"十三五"规划中的气候变化目标。在保证经济最低增速(6.5%)的前提下,中国二氧化碳的排放总量可以比优化方案再多下降约14%。(2)建筑业、交通运输及仓储业仍然是中国重要的支柱产业,在国民经济整体的占比份额仍需扩大。(3)从生产的角度看,中国产业结构必须全面向第三产业服务业转型,全面提高国民经济中第三产业的比重,尤其是加大生活服务业类部门的产出量。(4)为了满足"绿色、低碳"的约束限制,半数以上的二产部门的生产规模都应有所降低,尤其是能源部门和金属加工业部门。 相似文献
672.
本文将金融节能与金融发展同时引入传统LMDI分解模型,并融合脱钩弹性指数,分析了两者对碳排放变化的影响机理。在此基础上,本文还检验了1997—2015年中国29个省区金融节能与金融发展的碳排放效应。研究发现:首先,尽管1997—2015年中国碳排放规模的扩张趋势较为明显,短期来看,这一演变仍然大体经历了三个阶段,即碳排放增量持续扩张期、碳排放增量波动下降期以及碳排放增量平稳期。其次,不仅金融节能、金融发展以及经济增长是在短期和长期诱发中国碳排放变化的三个最主要因素,而且前两者对中国碳排放变化的影响还大于后者。再次,金融节能对中国碳排放变化的短期和长期作用方向始终与金融发展对中国碳排放变化的短期和长期作用方向相反。最后,金融节能和金融发展与中国碳排放变化之间在短期内基本维持弱脱钩或强负脱钩两种状态,而在长期呈现强负脱钩状态,通过分解这些脱钩弹性状态的诱因,不仅直接影响和交互影响的作用方向始终相反,而且两者还分别在金融节能与中国碳排放脱钩弹性变动以及金融发展与中国碳排放脱钩弹性变动中发挥截然相反的作用。 相似文献
673.
674.
利用2005~2010年浙江省各县市区的社会经济数据和能耗数据,测算了各县市区的碳排放总量、人均碳排放量和地均碳排放量,采用空间自相关方法揭示了县域尺度下相邻县市区碳排放指标的空间关联性,运用地理加权回归模型定量描述了各县市区碳排放总量影响因素的空间异质性。研究结果表明:(1)研究期内,浙江省的碳排放总量从30 486万t增加到49 559万t。人均碳排放量和地均碳排放量也均呈增长趋势,且空间差异显著。(2)各县市区碳排放总量、人均碳排放量和地均碳排放量均存在较强的空间自相关性,总体上浙北浙东呈高高集聚,浙西南呈低低集聚。(3)人口和投资是影响碳排放总量的重要因素,且存在空间异质性。投资对浙西南碳排放的影响逐渐增大。 相似文献
675.
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677.
Schifter I Díaz L Rodríguez R Durán J Chávez O 《Environmental monitoring and assessment》2008,137(1-3):459-470
A remote sensing study was conducted in year 2006 in four locations of the Metropolitan Area of Mexico City (MAMC). Two of
the sites were the same studied back by us in year 2000 and by others in year 1994. A database was compiled containing 11,289
valid measurements for the carbon monoxide (CO), total hydrocarbons (THC), and nitric oxide (NO) exhaust vehicles emissions.
Valid measurements were binned for each pollutant by the vehicle specific power (between −5 and 20 kW tonne−1) for the 2000 and 2006 databases. The mean average CO, THC, and NO emissions for year 2006 were determined to be 1.10 ± 0.18 vol.%,
299 ± 88.4 ppm, and 610 ± 115.0 ppm, respectively. Matching the vehicle driving patterns of the fleet measured in year 2000
with the emissions factors obtained in this work, allows estimating the trends in the exhaust emissions of vehicles in the
MAMC. The adjusted results of the remote sensing study performed in year 2006 shows that the fleet has decrease 22% in CO
and 17% in NO emissions, with small change in total hydrocarbons emissions. The improvements could be related with the introduction
in year 2001 of vehicles that met tighter emissions standards, particularly for nitrogen oxides. 相似文献
678.
W. Z. Khan 《Environmental monitoring and assessment》2001,71(2):123-142
The reduction of SO2 by ammonia gas additionduring staged combustion of bituminous coal has beenstudied in a 2 m high fluidized bed combustor of 30 cmstatic bed height and a freeboard height of 100 cm.The coal was introduced to the combustor at 42 cmabove the distributor and the ammonia gas was injectedat 52 cm above the distributor by an uncooledstainless steel injector. Experiments were carriedout to investigate effects of ammonia gas injection onSO2 emissions of (i) air staged levels, (ii) excess air levels, (iii) primary air factor, PAF(ratio of primary to stoichiometric air), (iv) NH3:SO2 molar ratio, and (v) fluidizingvelocity. Experiments were carried out under a newtechnique of air staging called Pseudo-stagedCombustion, maintaining the excess air level andfluidizing velocity between 17 and 70% and between0.7 and 2.0 m sec-1, respectively. A maximum reduction of92% was obtained at 37% excess air, at NH3:SO2 molar ratio of 5.5. The effective NH3:SO2 molar ratio was found to be between 3.0 and5.5, which is true for all staging and excess air levels.A greater removal of SO2 with NH3 injectionduring staged combustion is probably due to this newstaging technique. The Pseudo-staging reducestemperature through the freeboard and flue for theoccurance of as NH3 + SO2 reactions. Thesereactions are reported to be low temperaturereactions. The NH3 carry over was less than 83 ppm for all operating conditions. The present studydemonstrates that staged combustion coupled withammonia injection can reduce SO2 emissions. 相似文献
679.
Eva Leotz-Gartziandia Véronique Tatry Patrick Carlier 《Environmental monitoring and assessment》2000,65(1-2):155-163
The fraction of atmospheric semi-volatile organic compounds (SVOC) is partitioned between the gaseous and particulate phases. Certain of these compounds eg. polynuclear aromatic hydrocarbons (PAH) and their derivatives have been shown to exhibit mutagenic or carcinogenic properties. Emissions from diesel engines are an important source of these contaminants. In a dilution chamber, we studied a diesel engine emissions. It is shown firstly, that the gaseous fraction is predominant (by up to 20 times) with respect to the particulate phase. Secondly, the polar compounds, neglected in the majority of previous studies, are the predominant species. A test campaign was carried out in Paris-Porte d'Auteuil which yielded similar results to the laboratory experiments. 相似文献
680.
R. San José L.D. Pedraza I. Salas R.M. González 《Environmental monitoring and assessment》2000,65(1-2):469-476
In this contribution we show the integration of a mesoscale air quality model OPANA with the ISCST3 Gaussian model (EPA) in order to analyze the impact of different emission sources and particularly the traffic emission into the different gridboxes which define the OPANA Eulerian structure. The application is done over the Madrid (Spain) regional area with 80 × 100 km and gridboxes of about 5 km. Thousands of Gaussian runs over interested gridboxes are executed in order to simulate the traffic emissions from each gridbox. Each mobile unit is represented by a Gaussian point emitter. Input meteorological variables for the ISCST3 are taken from the OPANA mesoscale air quality model. Results shows that it is possible to model the impact of traffic emissions over each gridbox. A short comparison with air quality monitoring in each gridbox is also shown. 相似文献