汽车燃料和排放物的快速气相色谱分析

1　IntroductionGaschromatographyisthemostfrequentlyusedmethodsforthespeciationandquantificationoforganiccompoundsingasphaseandliquidphase .Thechemicalanalysisoforganiccompoundsintheautomotivefuelsandexhaustspeciesisanextremelyimportantandcomplexprocedure …     

燃用甲醇燃料的发动机尾气排放

本文主要报导了在二冲程、四冲程汽油机及柴油机上燃用甲醇-汽油混合燃料、M_(100)甲醇燃料的发动机尾气排放方面所做的研究,并与燃用汽油、柴油的尾气排放进行了对照。结果表明,无论是甲醇-汽油混合燃料,还是M_(100)甲醇燃料尾气排放,都较汽油、柴油尾气排放的常规污染物,均有不同程度的减少。因此,应用甲醇燃料对改善环境是有益的。     

Rh-Al-MCM-41上NO选择性催化还原的原位红外研究

利用气-固相固定床反应装置考察了Rh交换的Al-MCM-41在高气体空速条件下对贫燃NOx的选择性催化还原活性,考察了氧含量对其的影响。结果表明,在200000h~(-1)的气体空速、O_2/C_3H_6=20、603K时,NO转化率为74.3％。利用原位FTIR技术研究了该催化剂的表面吸附物种及表面程序升温反应行为,并结合实验观察探讨了贫燃条件下Rh-Al-MCM-41催化剂上NO的选择性催化还原机理。     

我国汽车尾气污染,污染控制与对策

本文综述了我国汽车尾气污染的现状与发展趋势，着重阐述了我国汽车尾气的催化剂研制和催化净化器技术水平和现状，提出了我国汽车尾气污染控制技术的发展方向，并探讨了减少汽车尾气污染的对策和建议。     

汽车尾气催化转化器模型研究进展

本文主要介绍汽车尾气催化转化器模型的研究进展 ,包括反应器内气体流动特性、单通道反应器内的传递现象和反应动力学、通道间的热传递和反应行为的模拟 ;并指出认识反应器内的各种特性和规律对设计汽车尾气催化转化器的必要性和意义     

Isomer distribution of nitrotriphenylenes in airborne particles, diesel exhaust particles, and the products of gas-phase radical-initiated nitration of triphenylene

The formation of mutagenic nitro-polycyclic aromatic hydrocarbons (NPAHs) 1- and 2-nitrotriphenylene (1- and 2-NTP) via gas-phase OH or NO₃ radical-initiated reactions of triphenylene was demonstrated for the first time using a flow reaction system. In contrast with the results of conventional electrophilic nitration, 2-NTP was formed in larger yield than 1-NTP, but this is consistent with the mechanism proposed for gas-phase radical-initiated nitration of PAH. In diesel exhaust particle (DEP) samples, both 1- and 2-NTP were identified and their concentrations determined, as well as 1-nitropyrene (1-NP), which is a representative combustion-derived NPAH: the mean concentrations of 1-NTP, 2-NTP, and 1-NP were 4.7, 1.9, and 32 pmol mg_DEP^–1, respectively. The mean 2-NTP/1-NTP, 1-NTP/1-NP, and 2-NTP/1-NP ratios in samples of airborne particles collected in a residential area in Osaka, Japan, were>1.55,<0.25, and 0.37, respectively; these values are much higher than those of the DEP samples. This finding indicates that there is another source for airborne NTPs, especially 2-NTP, apart from diesel exhaust. These results strongly suggest that airborne NTPs originate from atmospheric processes such as radical-initiated reactions of triphenylene, and this has a significant influence on the atmospheric occurrence of NTPs.     

废气治理的低温等离子体-催化协同净化技术

低温等离子体 催化协同净化技术具有能耗低、投资少、处理效率高、不产生二次污染等显著优点备受人们的关注。从挥发性有机化合物 (VOC)的转化、氮氧化合物的脱除、汽车尾气净化等不同废气治理的角度 ,概括了目前国内外在这方面的研究进展 ,最后提出了该项技术在环境保护领域的应用前景及研究方向     

汽车尾气净化催化剂涂层改性研究

汽车尾气净化催化剂的净化转化效果及其耐久性，与催化剂涂层的涂覆量以及涂层和载体的结合强度密切相关。本文研究了几种不同类型表面活性剂对浆料固体含量、涂层涂覆量以及涂层结合强度的影响。研究结果表明，不使用表面活性剂时，30％为最佳的固体含量；在使用表面活性剂的情况下，浆料的固体含量可以提高至35％。非离子型表面活性剂有助于提高催化剂涂层涂覆量，而使用离子型表面活性剂的浆料球磨过程中产生大量泡沫，无法涂覆。使用非离子型表面活性剂的催化剂涂层的结合强度最好。     

Characterization particulate matter from several Chinese cooking dishes and implications in health effects

Cooking fume produced by oil and food at a high temperature releases large amount of fine particulate matter(PM) which have a potential hazard to human health. This chamber study investigated particle emission characteristics originated from using four types of oil(soybean oil, olive oil, peanut oil and lard) and different kinds of food materials(meat and vegetable). The corresponding emission factors(EFs) of number, mass, surface area and volume for particles were discussed. Temporal variation of size-fractionated particle concentration showed that olive oil produced the highest number PM concentration for the entire cooking process. Multiple path particle dosimetry(MPPD) model was performed to predict deposition in the human respiratory tract. Results showed that the pulmonary airway deposition fraction was the largest. It was also found that particles produced from olive oil led to the highest deposition. We strongly recommend minimizing the moisture content of ingredients before cooking and giving priority to the use of peanut oil instead of olive oil to reduce human exposure to PM.     

上海世博规划区交通干道污染物对流扩散研究

采用计算流体动力学(CFD)技术,对不同来流风速大小、风向条件下的上海世博规划区内四条主要交通干道上的交通污染物对流扩散进行了三维数值仿真。获得了不同工况下交通污染物浓度的空间分布。通过数值仿真结果分析,探明了交通干道上的机动车尾气排放对世博规划区内空气质量的影响(各工况下世博规划区内的CO最大浓度为0.25～0.59mg/m3;东南、东北和南风向下规划区内的NO2最大浓度分别为0.037mg/m3、0.03mg/m3和0.03mg/m3,而北风和西风下规划区建筑群内NO2最大浓度分别为0.068mg/m3和0.12mg/m)3,并揭示出应该重视靠近交通干道的建筑物附近的空气质量改善,特别是要重视靠近卢浦大桥两侧的建筑群周围空气质量改善(卢浦大桥两侧的建筑群周围NO2最大浓度已稍大于《环境空气质量标准》规定的一级标准浓度限值)。