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轻型汽油车工况法排放检测方法相关性研究 总被引:2,自引:1,他引:2
研究了任用轻型汽油车稳态ASM、瞬态IMl95、GB18352.1—2001要求的全工况、GB18352.1—2001中的城市工况以及城市工况的第一个循环工况共5种不同的排放检测方法的相关性。测试并分析了3台本田雅阁车辆在这5种排放检测方法下的排放特性。结果表明,瞬态排放检测方法比稳态ASM方法能较全面地反映车辆的技术状态,瞬态IM195与GB18352.1—200l中城市工况检测方法的相关性较高,其中HC与NOx高于90%,CO也达57%以上。 相似文献
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Ensuring a fleet of green aircraft is a basic step in mitigating aviation pollution issues that are expected to be worsen in the coming years due to rapid air traffic growth. This study proposed a novel methodology in green fleet planning in which both profit and green performance of airline are considered simultaneously and explicitly. To do this, a Green Fleet Index (GFI) is derived as an indicator to quantify the green performance of airline’s fleet. It measures the degree of airline compliance with a standard requirement in terms of emission, noise, and fuel consumption. A bi-objective dynamic programming model is then formulated to find optimal aircraft acquisition (lease or purchase) decision by minimizing GFI and maximizing profit. Several interesting results are obtained: (1) considering environmental issue as secondary objective yields a greener fleet; (2) airline’s profit is affected, but could be recovered from environmental cost savings; (3) increasing load factor is an effective operational improvement strategy to enhance airline’s green performance and raise profit level. It is anticipated that the framework developed in this study could assist airlines to make a smart decision when considering the need to be green. 相似文献
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Environmental improvement and energy issues are increasingly becoming more important as worldwide concerns. Natural gas is
a good alternative fuel that can help to improve these issues because of its large quantity and clean burning characteristics.
This paper provides the experimental performance results of a Bi-Fuel engine that uses Compressed Natural Gas as its Primary
fuel and gasoline as its secondary fuel. This engine is a modification of the basic 1.4-liter gasoline engine. Generally,
on the unmodified base engine, torque and power for CNG fuel are considerably lower than gasoline fuel. In this paper, the
influence of fuels on wall temperature, performance and emissions are investigated. 相似文献
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采用王水湿式消化处理样品,建立了ICP-AES法同时测定霍加拉特剂中Mn、Cu、Na、Al、Ca、Mg和Fe等7种金属元素的方法。通过谱线选择、条件优化和基体匹配等方法消除元素间干扰和基体效应,探讨了酸类型及酸度值对谱线强度的影响,研究了溶液浓度对精密度及线性相关系数的影响。方法的线性相关系数均大于0.999,Mn、Cu、Na、Al、Ca、Mg和Fe的最佳谱线分别为Mn257.610nm、Cu327.393nm、Na589.592nm、Al396.153nm、Ca317.933nm、Mg285.213nm、Fe238.204nm,相应的检出限分别为0.0008、0.0009、0.012、0.028、0.010、0.001、0.004μg/mL,对应测定值的相对标准偏差分别为0.34%、0.87%、0.87%、0.54%、0.48%、0.84%、0.55%,加标回收率为94.2%~104.4%。该方法简便、快捷、准确,可在测定其他催化剂中金属含量时推广应用。 相似文献
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This article highlights eco-driving as an available policy option to reduce climate altering GHG emissions. Recognizing the need to reduce the environmental impact of its fleet operations, the City of Calgary is a leader in developing programs and policies that aim to reduce GHG emissions and associated pollutants resulting from the use of fossil fuels. Among local action taken against climate change, the City sought to quantify CO2 emissions reductions from their municipal fleet as a result of eco-driver training, with a specific focus on engine idling. Fifteen drivers from the Development & Building Approvals Business Unit had in-vehicle monitoring technology (CarChips®) installed into their vehicles as part of a three-phase research process. The results show that gasoline and hybrid vehicles decreased average idling between 4% and 10% per vehicle per day, leading to an average emissions decrease of 1.7 kg of CO2 per vehicle per day. 相似文献
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There is increasing interest in understanding and achieving changes in travel behaviour, but a focus on individual behaviour change may overlook the potential for achieving change via transformation at the levels of institutions, cultures and societies – the domains of sociological inquiry. In this paper, we review sociological contributions to the literature on travel and ‘mobilities’. We summarise four key themes which supplement or contradict arguments made in mainstream transport debates on behaviour change. The first involves focusing on travel ‘practices’ as social entities with dynamics of their own, rather than on individual behaviours. The second relates to the changing natures of societies, and the implications for travel. The third explores and interprets the issue of car dependence in ways which highlight the ethical, experiential and emotional dimensions associated with car use, its symbolic role in societies increasingly concerned with consumption, and its differing roles within different cultures. Finally, the ‘new mobilities paradigm’ highlights issues such as the increasing links between travel and new technologies, and the primacy of social networks in influencing travel decisions. These themes emphasise the importance of understanding the broader contexts in which travel choices are made. In particular, the implication is that the creation of more sustainable travel patterns will require changes at a range of social levels, not simply in individual behaviours, and that changes to transport will inevitably be linked with, and influenced by, broader changes in the values and practices developed by societies as a whole. 相似文献