...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Environmental Science & Technology >Determination of Single Particle Mass Spectral Signatures from Light-Duty Vehicle Emissions
【24h】

Determination of Single Particle Mass Spectral Signatures from Light-Duty Vehicle Emissions

机译：从轻型车辆排放中确定单颗粒质谱特征

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

In this study,28 light-duty gasoline vehicles (LDV) were operated on a chassis dynamometer at the California Air Resources Board Haagen-Smit Facility in El Monte,CA.The mass spectra of individual particles emitted from these vehicles were measured using aerosol time-of-flight mass spectrometry (ATOFMS).A primary goal of this study involves determining representative size-resolved single particle mass spectral signatures that can be used in future ambient paniculate matter source apportionment studies.Different cycles were used to simulate urban driving conditions including the federal testing procedure (FTP),unified cycle (UC),and the correction cycle (CC).The vehicles were selected to span a range of catalytic converter (three-way,oxidation,and no catalysts) and engine technologies (vehicles models from 1953 to 2003).Exhaust particles were sampled directly from a dilution and residence chamber system using particle sizing instruments and an ATOFMS equipped with an aerodynamic lens (UF-ATOFMS) analyzing particles between 50 and 300 nm.On the basis of chemical composition,10 unique chemical types describe the majority of the particles with distinct size and temporal characteristics.In the ultrafine size range (between 50 and 100 nm),three elemental carbon (EC) particle types dominated,all showing distinct EC signatures combined with Ca,phosphate,sulfate,and a lower abundance of organic carbon (OC).The relative fraction of EC particle types decreased as particle size increased with OC particles becoming more prevalent above 100 nm.Depending on the vehicle and cycle,several distinct OC particle types produced distinct ion patterns,including substituted aromatic compounds and polycyclic aromatic hydrocarbons (PAH),coupled with other chemical species including ammonium,EC,nitrate,sulfate,phosphate,V,and Ca.The most likely source of the Ca and phosphate in the particles is attributed to the lubricating oil.Significant variability was observed in the chemical composition of particles emitted within the different car categories as well as for the same car operating under different driving conditions.Two-minute temporal resolution measurements provide information on the chemical classes as they evolved during the FTP cycle.The first two minutes of the cold start produced more than 5 times the number of particles than any other portion of the cycle,with one class of ultrafine particles (EC coupled with Ca,OC,and phosphate) preferentially produced.By number,the three EC with Ca classes (which also contained OC,phosphate,and sulfate) were the most abundant classes produced by the nonsmoking vehicles.The smoker category produced the highest number of particles,with the dominant classes being OC comprised of substituted monoaromatic compounds and PAHs,coupled with Ca and phosphate,thus suggesting used lubricating oil was associated with many of these particles.These studies show,by number,EC particles dominate gasoline emissions in the ultrafine size range particularly forthe lowest emitting newer vehicles,suggesting the EC signature alone cannot be used as a unique tracer for diesels.This represents the first report of high time- and size-resolved chemical composition data showing the mixing state of nonrefractory elements in particles such as EC for vehicle emissions during dynamometer source testing.
机译：在这项研究中，在加利福尼亚州埃尔蒙特市的加州空气资源委员会Haagen-Smit设施的底盘测功机上操作了28辆轻型汽油车（LDV），使用气溶胶时间测量了这些车辆散发的单个颗粒的质谱图飞行质谱（ATOFMS）。这项研究的主要目标是确定可用于未来环境颗粒物源分配研究的代表性尺寸分辨的单颗粒质谱特征。使用不同的周期来模拟城市驾驶条件，包括联邦测试程序（FTP），统一周期（UC）和修正周期（CC）。选择的车辆可用于催化转化器（三元，氧化和无催化剂）和发动机技术（车辆模型）的范围1953年至2003年）。使用颗粒分级仪和配备空气动力学透镜（UF）的ATOFMS直接从稀释和停留室系统中取样排气颗粒-ATOFMS）分析50至300 nm之间的粒子。根据化学成分，有10种独特的化学类型描述了大多数具有不同尺寸和时间特征的粒子。在超细尺寸范围（50至100 nm）中，三种元素碳（EC）颗粒类型占主导地位，所有特征均与Ca，磷酸盐，硫酸盐和较低的有机碳（OC）结合表现出独特的EC特征。随着OC颗粒变得越来越普遍，EC颗粒类型的相对分数随颗粒尺寸的增加而降低大于100 nm。取决于车辆和周期，几种不同的OC颗粒类型会产生不同的离子图谱，包括取代的芳族化合物和多环芳烃（PAH），再加上铵，EC，硝酸盐，硫酸盐，磷酸盐，V等其他化学物质以及钙。颗粒中最可能的钙和磷酸盐来源是润滑油。在化学成分中观察到了显着的变化。在不同的汽车类别中以及在不同驾驶条件下运行的同一汽车中排放的f粒子。两分钟的时间分辨率测量提供了有关FTP循环期间化学类别的信息，例如在冷启动的前两分钟是循环中任何其他部分的颗粒数的5倍以上，优先生产出一类超细颗粒（EC与Ca，OC和磷酸盐结合）。按数量，这三个具有Ca类的EC（也包含OC） ，磷酸盐和硫酸盐）是非吸烟车辆产生的最丰富的类别。吸烟者类别产生的颗粒数量最多，主要类别是由取代的单芳族化合物和多环芳烃组成的OC，再加上Ca和磷酸盐，因此建议使用这些颗粒中有许多与润滑油有关。这些研究表明，从数量上讲，EC颗粒在PA的超细尺寸范围内占主导地位。特别是对于排放量最低的新车，不能仅凭EC签名就不能用作柴油的唯一示踪剂。这是有关高分辨时间和尺寸化学成分数据的首份报告，该数据显示了非难熔元素在颗粒（例如EC）中的混合状态用于测功机源测试期间的车辆排放。

著录项

  • 来源
    《Environmental Science & Technology》 |2005年第12期|p.4569-4580|共12页
  • 作者

    DAVID A.SODEMAN; STEPHEN M.TONER; KIMBERLY A.PRATHER;

  • 作者单位

    Department of Chemistry and Biochemistry,Scripps Institution of Oceanography,University of California,San Diego,La Jolla,California 92093-0314;

    Department of Chemistry and Biochemistry,Scripps Institution of Oceanography,University of California,San Diego,La Jolla,California 92093-0314;

    Department of Chemistry and Biochemistry,Scripps Institution of Oceanography,University of California,San Diego,La Jolla,California 92093-0314;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 环境化学;
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号