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Jia Liu Yunshan Ge Xin Wang Lijun Hao Jianwei Tan Zihang Peng Chuanzhen Zhang Huiming Gong Ying Huang 《环境科学学报(英文版)》2017,29(7):238-248
In this study, the particle size-resolved distribution from a China-3 certificated light-duty diesel vehicle was measured by using a portable emission measurement system (PEMS). In order to examine the influences of vehicle specific power (VSP) and high-altitude operation, measurements were conducted at 8 constant speeds, which ranged from 10 to 80 km/hr at 10 km/hr intervals, and two different high altitudes, namely 2200 and 3200 m. The results demonstrated that the numbers of particles in all size ranges decreased significantly as VSP increased when the test vehicle was running at lower speeds (< 20 km/hr), while at a moderate speed (between 30 and 60 km/hr), the particle number was statistically insensitive to increase VSP. Under high-speed cruising conditions, the numbers of ultrafine particles and PM2.5 were insensitive to changes in VSP, but the numbers of nanoparticles and PM10 surged considerably. An increase in the operational altitude of the test vehicle resulted in increased particle number emissions at low and high driving speeds; however, particle numbers obtained at moderate speeds decreased as altitude rose. When the test vehicle was running at moderate speeds, particle numbers measured at the two altitudes were very close, except for comparatively higher number concentrations of nanoparticles measured at 2200 m. 相似文献
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We studied engine-out soot samples collected from a heavy-duty direct-injection diesel engine and port-fuel injection gasoline spark-ignition engine. The two types of soot samples were characterized using Raman spectroscopy with different laser powers. A Matlab program using least-square-method with trust-region-reflective algorithm was developed for curve fitting. A DOE (design of experiments) method was used to avoid local convergence. The method was used for two-band fitting and three-band fitting. The fitting results were used to determine the intensity ratio of D (for “Defect” or “Disorder”) and G (for “Graphite”) Raman bands. It is found that high laser power may cause oxidation of soot sample, which gives higher D/G intensity ratio. Diesel soot has consistently higher amorphous/graphitic carbon ratio, and thus higher oxidation reactivity, compared to gasoline soot, which is reflected by the higher D/G intensity ratio in Raman spectra measured under the same laser power. 相似文献
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上海市全面实行排污许可证交易的可行性探讨 总被引：3，自引：0，他引：3
排污许可证交易系统应建立在一个完善和有效的排污许可证管理体制基础上。文章认为上海市现有排污许可证体制的经济内涵、产权、初始分配方式、基价体系等方面必须进行改革和完善。与发达国家实行的排污许可证体制相比，上海市实行的排污许可证体制缺乏相应的经济内涵，只是排污许可“执照”体制，上海市的排污许可证交易实际上是排污许可“执照”交易。根据上海市现行排污许可证体制的经济内涵及实施现状来看，近期内全面推行真正意义上的排污许可证交易所必需的条件还未成熟。目前应当继续在黄浦江上游地区进行排污许可证交易，并在各方面进行探索，进一步积累经验。 相似文献
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制定大气污染物排放指标的技术原则与方法 总被引：1，自引：0，他引：1
实施排放大气污染物许可证制度的技术核心是确定排污指标。该文根据我国目前的环境管理状况、可利用的污染控制技术及经济水平,分别论述了以管理目标总量控制和质量目标总量控制为基础的核定排放大气污染物许可限值的技术原则与方法,文中也初步分析了几个试点城市的典型经验 相似文献
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机动车污染物排放标准与其检测方法是相辅相成的，不同的机动车检测方法对应不同的机动车排放污染物限值。该文主要对机动车排放检测运行体系中的怠速和简易工况检测方法进行了对比性研究，并对机动车实施常规检测的年检和监督手段的路检进行了对比分析，从而得出：工况法检测对于尾气排放情况的模拟要优于怠速法检测，并可对NOx进行有效控制，所以建议在有条件的地区，应该尽量实施工况法检测：年检和路检的数据有较大的差异，反映出对在用车的监督不力，今后应加强；高排放车辆的贡献率所占的比例与发达国家相比太小，说明机动车总体控制水平较低。 相似文献
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通过实验的方法对怠速条件下汽车排气污染物在排气尾流中的扩散特性进行了研究.测定了怠速条件下汽车排气尾流中的污染物体积分数及其分布,并比较分析了3种不同类型汽车的污染物排放体积分数及其变化.实验结果表明,怠速时汽车排气尾流中的污染物体积分数按照近似指数函数的趋势迅速降低到接近大气背景值;不同类型汽车排气尾流中的污染物体积分数的差别非常明显;排气方向对汽车排放污染物的扩散及其分布具有重要的影响.研究工作可以为怠速工况下汽车排气污染物对周围环境的影响评价提供更多的有用信息. 相似文献
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关于排污权交易的若干探讨 总被引：5，自引：0，他引：5
从排污权交易的基本概念,排污权的初始分配,交易机制等方面讨论中,提出应按我国的环境管理模式排污权交易政策,发挥其在总量控制以及环境管理的特殊作用;排污权初始分配应实行偿形式;其交易适宜在较大的总量控制区域;政府在交易中可抽取一定比例排污权作为“交易税”等观点。 相似文献
9.
Xianbao Shen Zhiliang Yao Qiang Zhang David Vance Wagner Hong Huo Yingzhi Zhang Bo Zheng Kebin He 《环境科学学报(英文版)》2015,27(5):209-220
A database of real-world diesel vehicle emission factors, based on type and technology, has been developed following tests on more than 300 diesel vehicles in China using a portable emission measurement system. The database provides better understanding of diesel vehicle emissions under actual driving conditions. We found that although new regulations have reduced real-world emission levels of diesel trucks and buses significantly for most pollutants in China,NOx emissions have been inadequately controlled by the current standards, especially for diesel buses, because of bad driving conditions in the real world. We also compared the emission factors in the database with those calculated by emission factor models and used in inventory studies. The emission factors derived from COPERT (Computer Programmer to calculate Emissions from Road Transport) and MOBILE may both underestimate real emission factors, whereas the updated COPERT and PART5 (Highway Vehicle Particulate Emission Modeling Software) models may overestimate emission factors in China. Real-world measurement results and emission factors used in recent emission inventory studies are inconsistent, which has led to inaccurate estimates of emissions from diesel trucks and buses over recent years. This suggests that emission factors derived from European or US-basedmodels will not truly represent real-world emissions in China. Therefore, it is useful and necessary to conduct systematic real-world measurements of vehicle emissions in China in order to obtain the optimum inputs for emission inventory models. 相似文献
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文章分析了排污收费制度、企业点源水污染治理情况和城市污水处理厂的现状，提出运用经济动力，按照“污染者付费”的原则，形成排污交易市场，使污水处理走产业化发展之路。 相似文献
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通过分析吉林省"十二五"期间总量减排取得的成效及存在的问题,提出吉林省"十三五"污染物总量控制政策及对策措施。此项研究是吉林省"十三五"规划前期研究的重要内容,对于吉林省今后的环境管理和总量控制规划的工作思路、发展方向的调整和转变,提高总量控制规划的可操作水平,促进新时期全省环境保护工作的开展方面都有借鉴意义。 相似文献
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提出1种检测在用轻型汽油车尾气排放的新方法——机动车实用路况法（Vehicle Road Available Method,VRAM）,它采用 AVL Digas4000五气分析仪测量尾气各成份浓度,根据具体车型设定充量系数和时间差等参数,所得计算结果与汽车排放总量分析系统（Vehicle Mass Analysis System,VMAS）测量结果具有良好的相关性。作为对该方法可行性的验证,将在用轻型汽油车分类后,选取6种代表性车型进行了试验验证。指出人为因素、环境因素对实用路况法（VRAM）的相关性影响较大,但成本和便利性上的优势使得这种方法仍具有极强的实用价值。 相似文献
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大气排污交易政策实施的技术原则 总被引：1，自引：0，他引：1
排污交易政策由泡泡政策、补偿政策、净得政策及排污量存储政策组成。现阶段我国实施大气排污交易政策主要在同一厂区“以新带老”、排污补偿及可用购买盈余排污量来达到排放标准三方面进行;还论述了排污交易量、排污交易费用确定的原则。 相似文献
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根据对胶州湾水质的实际调查结果,确定DIN,COD为胶州湾的主要污染因子。对胶州湾陆源污染物现状入海量进行调查,并以2008年为基准年,以COD,NH3-N为预测因子,预测2010年胶州湾各排污单元污染物增加情况。提出基于现实、分阶段实行目标总量控制的总量分配原则,根据国家和山东省给青岛市下达的总量控制指标和2008年青岛主要污染物实际排放情况,确定2010年胶州湾COD排放总量控制目标为34675t,NH3-N入海通量总量控制目标为6943t,并对各排污单元的排放总量控制目标值进行了分配。 相似文献
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Rafael Fleischman Ran Amiel Jan Czerwinski Andreas Mayer Leonid Tartakovsky 《环境科学学报(英文版)》2018,30(5):273-286
Retrofitting older vehicles with diesel particulate filter(DPF) is a cost-effective measure to quickly and efficiently reduce particulate matter emissions. This study experimentally analyzes real-world performance of buses retrofitted with CRT DPFs. 18 in-use Euro III technology urban and intercity buses were investigated for a period of 12 months. The influence of the DPF and of the vehicle natural aging on buses fuel economy are analyzed and discussed. While the effect of natural deterioration is about 1.2%–1.3%, DPF contribution to fuel economy penalty is found to be 0.6% to 1.8%, depending on the bus type. DPF filtration efficiency is analyzed throughout the study and found to be in average 96% in the size range of 23–560 nm. Four different load and non-load engine operating modes are investigated on their appropriateness for roadworthiness tests. High idle is found to be the most suitable regime for PN diagnostics considering particle number filtration efficiency. 相似文献
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采用SEMTECH-D车载排放测试仪测量了东风柴油卡车在城市实际道路工况以及等速和加速工况下的油耗及污染物排放状况.测试结果显示,测试卡车实际道路综合百公里油耗为17.8L,NOx、CO和HC排放因子分别为3.96、8.86和2.15g·km-1.其中主干道路况相对较差,油耗与排放因子较高,是所有测试道路平均水平的1.3～1.8倍左右.研究结果表明,重型车油耗及污染物排放与各行驶工况下的速度、加速度均密切相关,车辆在高速加速行驶状态下易产生高排放.车辆在30～50km·h-1速度区间内等速行驶时,油耗与排放因子最为经济且环境友好.车辆在加速行驶时,油耗与NOx、CO排放因子可达到城市实际道路平均水平的2.0、2.2、1.4倍,急加速时达到2.8、2.1、14倍.应用比功率概念可准确描述车辆在各运行工况下的排放水平,但在重型车上缺乏实验依据,有待进一步研究. 相似文献
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钱伯章 《石油化工环境保护》1997,(4):25-30
柴油机车应用于道路运输具有许多优点，但环境保护要求减少排气污染、颗粒排放污染至关重要，为此，强化柴油燃料规格是其主要的驱动力。本文介绍了美国，西欧和亚太地区柴油质量现状和趋势，分析了我国柴油燃料质量及其改进意见。 相似文献
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废弃塑料裂解油化技术 总被引：2，自引：0，他引：2
综述了废弃塑料进行热裂解和催化裂解以获得聚合单体、柴油、汽油和燃料气的工艺原理、工艺流程和常用的裂解催化剂。指出裂解油化技术是今后处理废弃塑料的主要方式之一。 相似文献