Ocskay Rita, Salma Imre, Wang Wan, Maenhaut Willy
Institute of Chemistry, Eötvös University, P.O. Box 32, H-1518, Budapest, Hungary.
J Environ Monit. 2006 Feb;8(2):300-6. doi: 10.1039/b513915e. Epub 2006 Jan 4.
Water-soluble inorganic ions in aerosol samples have been studied. The sample collection took place during summer in 2003 at a European background site which is operating within the framework of the European Monitoring and Evaluation Program. Gent type PM10 stacked filter unit (SFU) samplers were operated in parallel on a day and night basis to collect particles in separate coarse (2.0-10 microm) and fine (<2.0 microm) size fractions. Particulate masses were measured gravimetrically; the filters from one of the SFU samplers were analyzed by particle-induced X-ray emission spectrometry (PIXE) and instrumental neutron activation analysis (INAA). Filters from the other SFU sampler were analyzed by ion chromatography (IC) for major inorganic anions (MSA-, NO2(-), NO3(-), Cl-, Br-, SO4(2-), oxalate) and cations (Na+, K+, NH4(+), Mg2+, Ca2+). The water-soluble inorganic ions measured were responsible for 44% and 16% of the total fine and coarse particulate mass, respectively. In the fine size fraction, the main ionic components were SO4(2-) and NH4(+) accounting for about 90% of fine ionic mass. In the coarse fraction the main ionic components were Ca2+ and NO3(-), followed by SO4(2-). Significant day and night difference in the mass concentrations was observed only for fine NO3(-). The molar ratios of fine NH4(+) to SO4(2-) indicated their complete neutralization to (NH4)2SO4. According to the cation-to-anion ratios the coarse particles were alkaline, while the fine particles were slightly acidic or neutral. By comparing the corresponding concentrations obtained from PIXE/INAA and IC, we determined the water-extractable part of the individual species. We also investigated the effect of long-range transported air masses on the local air concentrations, and we found that the air quality of this background monitoring station was affected by regional pollution sources.
对气溶胶样品中的水溶性无机离子进行了研究。样品采集于2003年夏季在一个欧洲背景站点进行，该站点在欧洲监测与评估计划框架内运行。在白天和夜晚并行操作Gent型PM10叠层过滤装置（SFU）采样器，以分别收集粗颗粒（2.0 - 10微米）和细颗粒（<2.0微米）的颗粒物。通过重量法测量颗粒物质量；对其中一个SFU采样器的滤膜采用粒子诱导X射线发射光谱法（PIXE）和仪器中子活化分析法（INAA）进行分析。对另一个SFU采样器的滤膜采用离子色谱法（IC）分析主要无机阴离子（MSA - 、NO2(-)、NO3(-)、Cl - 、Br - 、SO4(2 - )、草酸盐）和阳离子（Na + 、K + 、NH4(+)、Mg2 + 、Ca2 + ）。所测量的水溶性无机离子分别占细颗粒物和粗颗粒物总质量的44%和16%。在细颗粒部分，主要离子成分是SO4(2 - )和NH4(+)，约占细颗粒离子质量的90%。在粗颗粒部分，主要离子成分是Ca2 + 和NO3(-)，其次是SO4(2 - )。仅在细颗粒NO3(-)的质量浓度上观察到显著的昼夜差异。细颗粒NH4(+)与SO4(2 - )的摩尔比表明它们完全中和形成了(NH4)2SO4。根据阳离子与阴离子的比例，粗颗粒呈碱性，而细颗粒呈弱酸性或中性。通过比较PIXE/INAA和IC获得的相应浓度，我们确定了各物种的水可提取部分。我们还研究了远距离传输气团对当地空气浓度的影响，发现该背景监测站的空气质量受到区域污染源的影响。
