ⅠA族和ⅡA族金属的消烟助燃效应及其理论

ⅠＡ三金属和ⅡＡ碱土金属元素是有灰型消烟助燃剂的功能元素，就各族内而言，这些ｓ区金属元素的消烟助燃效应与它们的热电离电离热成反比，此特征与烃火焰条件下碳烟生成的正离子机制有关，就两族间而言，ⅡＡ族金属的消烟助燃效应通常大于ⅠＡ族金属，该特征与ｓ区金属元素的火焰电离特性有关，在实质上，ｓ区金属元素的消烟助燃效应与它们在火焰条件下发生电离的活化能有关，基于碳烟生成的双途径模型，含ⅠＡ，ⅡＡ族金属消烟助     

Pt负载的铈锆固溶体的催化性能与表征

用柠檬酸法制备了CexZr1-xO(2x=0.5～1.0)铈锆固溶体,用浸渍法分别在铈锆固溶体上负载0.5%的Pt。用热重法(TG)测试了催化剂对碳烟的催化活性,Pt/Ce0.8Zr0.2O2显示了最高的催化活性。采用比表面(BET),X-射线衍射仪(XRD)和红外仪(FTIR)对催化剂进行了测试。结果表明:催化剂催化燃烧碳烟的活性与催化剂比表面积大小有关,可能是由于Pt在比表面积大的固溶体表面分散得更好,有利于氧溢出,促进碳烟的燃烧。     

Morphological and semi-quantitative characteristics of diesel soot agglomerates emitted from commercial vehicles and a dynamometer

Diesel soot aggregates emitted from a model dynamometer and 11 on-road vehicles were segregated by a micro-orifice uniform deposit impactor (MOUDI). The elemental contents and morphological parameters of the aggregates were then examined by scanning electron microscopy coupled with an energy dispersive spectrometer (SEM-EDS), and combined with a fractional Brownian motion (fBm) processor. Two mode-size distributions of aggregates collected from diesel vehicles were confirmed. Mean mass concentration of 339 mg/m3 (dC/dlogdp) existed in the dominant mode (180–320 nm). A relatively high proportion of these aggregates appeared in PM1, accentuating the relevance regarding adverse health e ects. Furthermore, the fBm processor directly parameterized the SEM images of fractal like aggregates and successfully quantified surface texture to extract Hurst coe cients (H) of the aggregates. For aggregates from vehicles equipped with a universal cylinder number, the H value was independent of engine operational conditions. A small H value existed in emitted aggregates from vehicles with a large number of cylinders. This study found that aggregate fractal dimension related to H was in the range of 1.641–1.775, which is in agreement with values reported by previous TEM-based experiments. According to EDS analysis, carbon content ranged in a high level of 30%–50% by weight for diesel soot aggregates. The presence of Na and Mg elements in these sampled aggregates indicated the likelihood that some engine enhancers composed of biofuel or surfactants were commonly used in on-road vehicles in Taiwan. In particular, the morphological H combined with carbon content detection can be useful for characterizing chain-like or cluster diesel soot aggregates in the atmosphere.     

无缝钢管厂轧制烟尘处理设计及运行

针对无缝钢管厂轧制烟尘的特殊性,采用一种全新的处理工艺流程——高频振动水膜法。运行实践表明：该处理工艺技术先进,投资省,运行成本低,操作简便,运行稳定,除尘效果好。     

Distribution,levels, and risk assessment of polycyclic aromatic hydrocarbons in the soot of some kitchens in the Cape Coast Metropolis of Ghana

The effect of using firewood for cooking, baking, and heating in poorly ventilated kitchens on the formation of polycyclic aromatic hydrocarbons (PAH) in kitchen soot in the Cape Coast Metropolis of Ghana has been studied. The kitchens in Ghana, especially those in the rural areas, are simple clay hut structures with small doors. The kitchens have little or no openings for ventilation and, as a result, the cook is exposed directly to high doses of smoke containing different compounds including PAH. In this study, a total of 42 soot samples were collected for 6 weeks from seven kitchens and analyzed using gas chromatography with flame-ionization detection (GC/FID). The average PAH concentration in the kitchen soot samples ranged from 0.7 to 445 µg kg^?1. The unit risk of PAH associated with the dermal contact/inhalation of the kitchen soot occurred at 7.4 × 10^?3 in children and at 4.8 × 10^?5 in the adults, showing the impact. However, the high level of PAH measured in this work especially that of benzo[a]pyrene (B[a]P) may cause cancer in the women who are exposed to the smoke. The study was therefore designed to find out the level of PAH in kitchen soot and their contributions as the monitoring tools in the assessment of risks and hazards of PAH in Ghana.     

用于碳烟燃烧的Cu0.05Ce0.95O催化剂活性氧物种的研究 ——等离子体的强化效应

研究等离子体对柠檬酸络合法制备的Cu0.05Ce0.95-CA催化剂表面结构和物种的强化效应. TPO、H2-TPR、O2-TPD、XRD、BET和XPS等测试结果表明,催化剂处于等离子放电区时,其氧化碳烟燃烧的活性显著增强.在介质阻挡放电电压为9kV时,起燃温度为243.1℃,比无等离子的情况降低了65.1℃;燃烧峰值温度为302.8℃,降低92.7℃.在等离子体存在下,Cu0.05Ce0.95-CA催化剂有着更大的比表面积和更小的晶粒粒径;等离子体可以提高催化剂表面游离态的CuO的分散度,并使得更多的Cu2+进入CeO2晶格,形成更多的Cuy2+Ce1-y4+O2-y2-□y固熔体,催化剂储氧容量增大,在催化剂表面生成更多的活性氧物种,其流动、迁移和转化促进催化剂产生更多的氧空穴,如此循环,持续促进碳烟催化燃烧.     

La_(1-x)Ce_xCu_yMn_(1-y)O_3/HZSM-5催化剂低温去除柴油机碳烟和NO_x

为实现对柴油机碳烟和NOx的低温同步去除,采用柠檬酸络合法制备分子筛负载钙钛矿型金属复合氧化物催化剂,应用X衍射分析仪(XRD)和电镜扫描仪(SEM)对催化剂性能进行表征,并在微型固定床反应器中对催化剂低温去除碳烟和NOx进行活性评价。利用程序升温反应(TPR)技术,进行催化剂活性评价、柴油机负荷和排放等特性实验。结果表明,A位用适量Ce部分取代La,B位用适量Cu部分取代Mn,可使碳颗粒燃烧温度降低,CO2选择性好,NOx转化率升高。La0.4Ce0.6Cu0.2Mn0.8O3/HZSM-5催化剂的最大NOx转化率为81.0%,Ti、Tm和Tf分别为250、350和475℃,表明该催化剂具有较好的催化活性,能在低温条件下去除碳烟和NOx。     

铈锆固溶体负载LaCoO_3催化碳烟的性能和表征

用柠檬酸法制备了铈锆固溶体负载不同量LaCoO3的催化剂。用热重法测试了催化剂样品对碳烟的催化活性。采用程序升温还原法(H2-TPR)、BET、X-射线衍射仪(XRD)和X-射线光电子能谱仪(XPS)对催化剂进行了测试。结果表明,铈锆固溶体表面形成了稳定的LaCoO3钙钛矿相结构;负载量为30%LaCoO3的催化剂具有最高的催化活性,起燃温度降到530℃;催化剂的催化活性与催化剂还原峰强度以及催化剂表面氧物种OII的含量紧密相关。     

催化型微粒捕集器的再生与压降数值研究

采用新的再生机理对催化型微粒捕集器（CPF）深床捕集微粒的氧化再生过程进行了建模,并将微粒捕集器中的压降分成5个部分分别计算,对其压降特性进行了数值研究。结果表明,新模型对深床捕集微粒的氧化再生计算与实验值吻合良好,比原模型更能反映微粒沉积的实际过程,深床捕集微粒的压降计算值也更精确。在排气流量大、温度高的工况下,深床捕集微粒的压降先迅速增大再减小的现象明显。研究结果能为工程应用提供验证手段,为CPF的优化设计提供依据。     

铸造烟尘治理技术

结合铸造工艺过程,分析介绍了铸造烟尘的来源及其危害,介绍了铸造粉尘的除尘技术,重点介绍了袋式除尘新设备的特点以及国外电弧炉烟尘的治理新技术.