乙醇汽油对减少机动车污染排放的机理研究与分析

以93#国Ⅲ乙醇汽油(E10)、93#国Ⅲ普通汽油和93#国Ⅳ普通汽油为实验对象,对GB18352.3-2005中要求限定的CO、HC和NOx,以及颗粒物(PM)和CO2等主要污染物的排放进行了测量和对比研究,并对CO、HC、PM、NOx、CO2和苯系物等污染物的形成原因和减排机理进行了分析.和93#国Ⅲ普通汽油相比,93 #国Ⅲ乙醇汽油(E10)排放的尾气中:CO降低了19.7％,HC降低了16.4％;和93#国Ⅳ普通汽油相比,93#国Ⅲ乙醇汽油(E10)排放的尾气中:CO降低了1.8％,HC降低了12.9％,CO2降低了2.4％.研究表明,乙醇汽油在减少CO、HC、NOx、颗粒物和苯系物等有毒物质排放方面具有显著功效,使用乙醇汽油可以减少环境污染物的排放,显著改善空气质量.     

Twenty-five years of biomonitoring lead in the Frankfurt/Main area

The present study is an example of the historical monitoring of heavy metals. The specific question it aims to explore is: to what extent has the lead content of selected organisms used for biomonitoring in Frankfurt/Main—one of the cities in Germany most heavily affected by automobile traffic—changed as a result of legislation on leaded gasoline?

Data on the lead content of the moss speciesBryum argenteum Hedw. from the years 1974, 1975 and 1978 and data on the lead content of the outer bark of the ash speciesFraxinus excelsior L. from 1973 served as the basis for the repeated measurements. Remeasurement was successful in 76.5% (i.e. 124 trees at 26 growth sites). The study produced the following results:

• ? As was expected, the lead content of the short-term accumulatorBryum argenteum Hedw. was distinctly lowered with a decreasing particulate lead concentration. However, the reduction factor varied greatly between the different growth sites.
• ? On the other hand, the lead content measured in the outer bark layers ofFraxinus excelsior L. has risen markedly during the past two decades. Whereas in 1973 nearly all trees examined displayed very low concentrations of lead (< 38 ppm), only 9.5% were still in this category in 1997 and nearly 30% exhibited high or even unacceptable lead concentrations (< 150 ppm → > 225 ppm). Various factors have to be taken into account to explain this increase. First of all, bark is a long-term accumulator for heavy metals like lead and its enrichment capacity could have increased as the surface becomes rougher over time. Furthermore, lead is most probably leached out of the bark to a lesser degree now than in the 1970s, owing to the reduced concentration of sulphuric acid in the rain. The dramatic growth of automobile traffic in the Frankfurt/Main area during the period covered by the study undoubtedly plays an important role as well.

     

井架背车液压系统故障诊断与处理

介绍了井架背车液压系统常见故障现场快速诊断方法,列举了常见故障处理实例及故障诊断效果。     

国产小轿车车内空气质量初步调查

对使用30d和1a左右的国产中档车（排气量1．5～2．01）进行了检测,结果表明：甲醛、氨和TVOC超标;苯、甲苯和二甲苯合格。分析了污染物超标原因,提出了建议。     

汽油车非常规污染物排放特性研究

选择3种不同排量的典型汽油车,基于国Ⅲ标准的轻型车排放测试循环,用SKC采样泵和2, 4-DNPH、Tenax TA采样管采集尾气中的非常规污染物,利用高效液相色谱仪和热脱附气相色谱质谱联用仪分析汽油车排放中醛酮类化合物和挥发性有机物的组成及含量,同时利用电子低压冲击仪研究了其颗粒物排放的粒径和质量浓度分布特征.结果表明,不同汽油车之间非常规污染物的比排放值有较大差异,3辆汽油车总醛酮比排放量分别为36.44、 16.71、 10.43 mg/km,TVOC分别为155.39、 103.75、 42.29 mg/km.排放的醛酮化合物中甲醛、乙醛、丙烯醛、丙酮和环己酮的检出含量较高,占总醛酮量的77.9%～89.7%,且绝大部分为有毒有害物质;废气中挥发性有机物绝大部分为芳香烃和烷烃,分别占总数的31.6%～39.2%和23.1%～27.9%,其中又以芳香烃类化合物甲苯、二甲苯和苯的检出含量最高,平均占TVOC的16.68%、 16.87%和5.23%;其颗粒物排放以超细颗粒物（<100nm）为主,高速工况下排放的颗粒物明显多于低速和中速工况.     

车用乙醇汽油与无铅汽油排放污染物检测结果的比较分析

为了掌握机动车使用乙醇汽油后排气污染物检测结果的浓度大小变化情况,对使用乙醇汽油和无铅汽油的机动车排放污染物检测结果进行比较分析,为车用乙醇汽油全面推广提供实际检测的科学数据。     

双提升管催化裂化装置隔离汽油沉降器后的风险分析及对策

分析了双提升管催化裂化装置隔离汽油沉降器的方法及隔离后存在的风险,根据分析结果提出相应对策。     

聚烯烃类废塑料热分解技术中催化剂的选择和机理初探

研究使用不同催化剂情况下聚烯烃类废塑料热分解回收燃油的技术,并对废塑料的热分解机理进行了探讨．结果表明,自制的含大孔径分子筛的ＮＬＧ系列催化剂具有较好的催化性能,在裂解温度４３０℃,催化温度为３６０℃情况下,热分解后油产率为８７．５％,油品中汽油馏分达４１．３％,辛烷值为８８．３,每ｔ生产成本仅１２０００元左右,循环使用２０５余次后,仍保持良好的催化性能．     

火灾、爆炸危险指数评价法在汽车加油站的应用

本文提出了火灾、爆炸危险指数评价法在汽车加油站应用时的一些系数的选取应用的几点意见 ,以期应用该评价法时更符合实际情况 ,更准确。并用实例加以说明     

木薯乙醇-汽油混合燃料生命周期排放多目标优化研究

建立了木薯乙醇-汽油混合燃料生命周期排放单目标和多目标优化模型.以生命周期CO,NO_x,PM,HC,SO_x,CO₂排放为优化目标,对木薯乙醇-汽油混合燃料生命周期排放进行了单目标及多目标优化,并进行了灵敏度分析.结果表明:多目标优化后木薯乙醇-汽油混合燃料的混合比例为63%.与原始值相比,多目标优化后生命周期CO排放略有升高,NO_x升高15%,PM升高19%;生命周期HC、SO_x和CO₂分别降低8%、50%和21%.