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141.
J. Jung J. H. Lee S. Song K. M. Chun 《International Journal of Automotive Technology》2008,9(4):423-428
Understanding the mechanism of carbon oxidation is important for the successful modeling of diesel particulate filter regeneration.
Characteristics of soot oxidation were investigated with carbon black (Printex-U). A flow reactor system that could simulate
the condition of a diesel particulate filter and diesel exhaust gas was designed. Kinetic constants were derived and the reaction
mechanisms were proposed using the experimental results and a simple reaction scheme, which approximated the overall oxidation
process in TPO as well as CTO. From the experiments, the apparent activation energy for carbon oxidation with NO2-O2-H2O was determined to be 40±2 kJ/mol, with the first order of carbon in the range of 10∼90% oxidation and a temperature range
of 250∼500°C. This value was exceedingly lower than the activation energy of NO2-O2 oxidation, which was 60±3 kJ/mol. When NO2 exists with O2 and H2O, the reaction rate increases in proportion to NO2. It increases nonlinearly with O2 or H2O concentration when the other two oxidants are fixed. 相似文献
142.
Chun-Hsiung Liao Po-Hsing Tseng Chin-Shan Lu 《Transportation Research Part D: Transport and Environment》2009,14(7):493-496
This paper examines carbon dioxide emissions of truck-only transportation using activity-based emission modelling and compares those with intermodal coastal shipping and truck movements. The results reveal that replacing long-haul truck transport with the intermodal can significantly reduce carbon dioxide emission significantly because of the efficiency of maritime fuel. 相似文献
143.
L.D. Poulikakos A.R. Lees K. Heutschi P. Anderegg 《Transportation Research Part D: Transport and Environment》2009,14(7):507-513
The European Union project Eureka Logchain Footprint is an ongoing project to identify road and rail vehicles by means of their environmental footprint as characterised by dynamic load, noise, ground borne vibrations and gaseous emissions induced by the vehicle. Part of the project involves the installation of road and rail footprint monitoring stations throughout Europe. This paper presents results of the road stations in Switzerland and the UK. Individual vehicle data from weigh-in-motion and noise are compared. The results indicate that a significant number of vehicles surpass the limits set in both countries. It was shown that the UK sites are generating higher noise levels than their Swiss counterparts; in part due to the much coarser aggregate embedded in the running course of the pavement employed in the UK. Such data can be used to create an incentive for vehicle types with a low footprint and a penalty for vehicles with a large footprint. 相似文献
144.
Christophe Rizet Michael BrowneEric Cornelis Jacques Leonardi 《Transportation Research Part D: Transport and Environment》2012,17(4):293-300
This article compares the energy consumption and CO2 emissions of supply chains in Belgium, France and UK looking in particular at, jeans, yogurts, apples, tomatoes and furniture. We use a generic methodology that allows comparability across the supply chain of products, supply chains, and countries. Our benchmarking show relatively high emissions for maritime transport and the consumer leg, while logistics activities such as storage and road freight exhibit relatively low emissions. The influences of distance, retail type, area density and consumer behaviour are also examined. 相似文献
145.
Dong- Ying Ju Michiharu Narazaki Hirofumi Kamisugi Haruyoshi Hirano . Department of Mechanical Engineering Saitama Institute of Technology Saitama Japan . Department of Mechanical Systems Engineering Utsunomiya University Utsunomiya Japan 《上海交通大学学报(英文版)》2000,(1)
IntroductionInordertoobtainimprovedmechanicalpropertiesandfatiguestrengthofmachinecomponents,stlchasgears,shaftsandsoon,carburizing-quenchingprocessasamethodofstirfacehardeningisoftenusedinindustry.Howevef,carbtirizing-quenchingisusuallyaccompaniedwithcarbonconcentrationandleadtodistortion,residualstressesandhardnessofsteelparts.Theeffectofcarboncontentisspeciallysignificantonphasetransformationbel1aviorThispaPerwillpresentthesimulationresultsoftheresidualstressfieldanddistortionofasteelcylin… 相似文献
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通过1根原梁、3根碳纤维与钢板复合加固梁和3根碳纤维加固梁的受弯性能试验,研究碳纤维与钢板复合加固钢筋混凝土梁的裂缝发展机理及裂缝宽度计算方法。研究表明,加固梁的裂缝间距和裂缝宽度均小于原梁,但次生裂缝有所增加;复合加固梁的裂缝发展速度比碳纤维加固梁缓慢,说明复合加固的限裂作用优于碳纤维;随着负载的增加,加固梁裂缝的发展速度加快,限裂作用随之减弱,最大裂缝宽度曲线出现突变,说明负载降低了加固的限裂作用,但负载对复合加固限裂作用的影响比碳纤维加固小。基于传统裂缝计算理论,引入复合加固粘结作用相关系数和负载影响系数,推导出考虑复合加固粘结作用及负载影响的复合加固梁裂缝宽度计算式。该公式的计算值与试验值吻合较好,计算方法简便,可用于工程设计。 相似文献
150.
以票价补贴、运营补贴和生态足迹成本为策略,基于可持续发展理念构建了财 政预算约束下公共交通的最优补贴模型.上层模型是在有限的财政预算、运输容量及生态 足迹限制下,获得最优的票价补贴、运营补贴及消化运输活动产生的生态足迹成本,实现 社会效用最大化;下层模型采用Logit 模型和用户均衡分配模型获得公交及小汽车的出 行方式和路网流量,实现出行成本最小化.为了验证模型的实用性,构建了简单路网进行 算例分析.结果显示:增加公共交通乘客的票价补贴,会吸引更多乘客使用公共交通,其效 果优于增加公交企业的运营补贴;考虑生态足迹约束下,实施82%的票价补贴和8%的运 营补贴其效用值最优. 相似文献