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371.
综述了美国氮氧化物排放交易项目的演进过程,总结其实践经验,并探讨美国经验对中国氮氧化物排放控制的借鉴意义。  相似文献   
372.
我国作为世界上第一大煤炭消费国和二氧化碳排放国,又是受气候变化影响最大的国家之一,在应对全球气候变化方面责无旁贷。在中国发展低碳排放经济和低碳城市的理念应运而生。全球气候变暖日益引起全国社会的普遍关注。2007全联合国政府问气候变化委员会(IPCC)发表了第4份全球气候评估的报告结果,指出了气候变暖是事实,人的活动是造成这种情况的最大的因素。  相似文献   
373.
正为强化科技支撑大气污染防治工作,贯彻落实国务院《大气污染防治行动计划》,科技部与环境保护部在组织实施《蓝天科技工程"十二五"专项规划》的基础上,对大气污染防治方面的科研成果及应用情况进行了全面梳理和筛选评估,编制形成了《大气污染防治先进技术汇编》(以下简称《技术汇编》),并于3月5日正式发布.《技术汇编》汇集了89项关键技术及130余项相应案例成果,涵盖电站锅炉烟气排放控制、工业锅炉及煤窑锅炉排放控制、典型有毒有害工业废气净化、机动车尾气排放控制、居室及公共场所典型空气污染物净化、无组  相似文献   
374.
正联合国气候变迁专家小组于11月2日推出第五个全球气候变迁评估报告.据法国国际广播电台报道,联合国气候变迁问题专家组11月2日在丹麦首都哥本哈根推出对全球气候状况的最新评估报告,报告以超乎寻常的强烈用词警告,人类面对地球生态环境快速恶化的风险,各国政府必须尽快行动,降低温室气体排放,实现在2100年前将温室气体排放量减至零,否则恐将引发生态和社会灾难.同时报告也指出,减排  相似文献   
375.
随着城市机动化的高速发展,西安市整体机动车现状的主要问题在于快速增加的机动车数量和低水平的尾气控制排放技术。通过对西安市机动车尾气超标排放的现象和原因进行研究分析,从排放标准、燃油品质和机动车工况多个方面提出了针对性的改善意见和处理措施,为西安市机动车尾气污染的预防、控制和治理提供了一定的科学依据。  相似文献   
376.
为了研究机场大气环境质量状况,在某机场选取三个监测点,在正常飞行条件下,对不同时间段污染物浓度进行监测与分析。测试结果表明:七天监测期间,机场及机场周围SO2、NO2浓度均未超标,PM10在机场内部有一天超标;各时间段SO2的贡献率在2.9%~12%,各时间段NO2的贡献率在6.9%~77%,机场飞机的尾气对周围空气质量的影响不容忽视。  相似文献   
377.
Stormwater runoff has been identified as a source of pollution for the environment, especially for receiving waters. In order to quantify and manage the impacts of stormwater runoff on the environment, predictive models and mathematical models have been developed. Predictive tools such as regression models have been widely used to predict stormwater discharge characteristics. Storm event characteristics, such as antecedent dry days (ADD), have been related to response variables, such as pollutant loads and concentrations. However it has been a controversial issue among many studies to consider ADD as an important variable in predicting stormwater discharge characteristics. In this study, we examined the accuracy of general linear regression models in predicting discharge characteristics of roadway runoff. A total of 17 storm events were monitored in two highway segments, located in Gwangju, Korea. Data from the monitoring were used to calibrate United States Environmental Protection Agency's Storm Water Management Model (SWMM). The calibrated SWMM was simulated for 55 storm events, and the results of total suspended solid (TSS) discharge loads and event mean concentrations (EMC) were extracted. From these data, linear regression models were developed. R2 and p-values of the regression of ADD for both TSS loads and EMCs were investigated. Results showed that pollutant loads were better predicted than pollutant EMC in the multiple regression models. Regression may not provide the true effect of site-specific characteristics, due to uncertainty in the data.  相似文献   
378.
Fifteen heavy-duty diesel vehicles were tested on chassis dynamometer by using typical heavy duty driving cycle and fuel economy cycle. The air from the exhaust was sampled by 2,4- dinitrophenyhydrazine cartridge and 23 carbonyl compounds were analyzed by high performance liquid chromatography. The average emission factor of carbonyls was 97.2 mg/km, higher than that of light-duty diesel vehicles and gasoline-powered vehicles. Formaldehyde, acetaldehyde, acetone and propionaidehyde were the species with the highest emission factors. Main influencing factors for carbonyl emissions were vehicle type, average speed and regulated emission standard, and the impact of vehicle loading was not evident in this study. National emission of carbonyls from diesel vehicles exhaust was calculated for China, 2011, based on both vehicle miles traveled and fuel consumption. Carbonyl emission of diesel vehicle was estimated to be 45.8 Gg, and was comparable to gasolinepowered vehicles (58.4 Gg). The emissions of formaldehyde, acetaldehyde and acetone were 12.6, 6.9, 3.8 Gg, respectively. The ozone formation potential of carbonyls from diesel vehicles exhaust was 537 mg O3/km, higher than 497 mg O3/km of none-methane hydrocarbons emitted from diesel vehicles.  相似文献   
379.
Carbon dioxide(CO2) emissions are a leading contributor to the negative effects of global warming. Globally, research has focused on effective means of reducing and mitigating CO2 emissions. In this study, we examined the efficacy of eco-industrial parks(EIPs) and accelerated mineral carbonation techniques in reducing CO2 emissions in South Korea.First, we used Logarithmic Mean Divisia Index(LMDI) analysis to determine the trends in carbon production and mitigation at the existing EIPs. We found that, although CO2 was generated as byproducts and wastes of production at these EIPs, improved energy intensity effects occurred at all EIPs, and we strongly believe that EIPs are a strong alternative to traditional industrial complexes for reducing net carbon emissions. We also examined the optimal conditions for using accelerated mineral carbonation to dispose of hazardous fly ash produced through the incineration of municipal solid wastes at these EIPs. We determined that this technique most efficiently sequestered CO2 when micro-bubbling, low flow rate inlet gas, and ammonia additives were employed.  相似文献   
380.
Based on the observation by a Regional Air Quality Monitoring Network including 16 monitoring stations, temporal and spatial variations of ozone(O3), NO2and total oxidant(Ox) were analyzed by both linear regression and cluster analysis. A fast increase of regional O3concentrations of 0.86 ppbV/yr was found for the annual averaged values from 2006 to 2011 in Guangdong, China. Such fast O3increase is accompanied by a correspondingly fast NOx reduction as indicated by a fast NO2 reduction rate of 0.61 ppbV/yr. Based on a cluster analysis, the monitoring stations were classified into two major categories – rural stations(non-urban) and suburban/urban stations. The O3concentrations at rural stations were relatively conserved while those at suburban/urban stations showed a fast increase rate of 2.0 ppbV/yr accompanied by a NO2 reduction rate of 1.2 ppbV/yr. Moreover, a rapid increase of the averaged O3 concentrations in springtime(13%/yr referred to 2006 level) was observed, which may result from the increase of solar duration, reduction of precipitation in Guangdong and transport from Eastern Central China. Application of smog production algorithm showed that the photochemical O3production is mainly volatile organic compounds(VOC)-controlled. However, the photochemical O3production is sensitive to both NOx and VOC for O3pollution episode. Accordingly, it is expected that a combined NOx and VOC reduction will be helpful for the reduction of the O3 pollution episodes in Pearl River Delta while stringent VOC emission control is in general required for the regional O3 pollution control.  相似文献   
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