Xie Ruikai, Jackson Kevin A, Seip Hans Martin, McLeod Cameron W, Wibetoe Grethe, Schofield Marie J, Anderson David, Hanssen Jan Erik
Department of Chemistry, University of Oslo, Blindern, P.B. 1033, Oslo, Norway.
J Environ Monit. 2009 Feb;11(2):336-43. doi: 10.1039/b805285a. Epub 2008 Nov 20.
To characterise the water-soluble inorganic components of PM(10) in the urban area of Sheffield, size-resolved aerosol samples were collected using an electric low pressure impactor (ELPI) during a 13-day sampling campaign in October and November 2006. Cl(-), NO(3)(-), SO(4)(2-), and NH(4)(+) were determined by ion chromatography, and Na(+), K(+), Mg(2+), and Ca(2+) by inductively coupled plasma-mass spectrometry. Back trajectories analyses revealed that the air masses could be classified into two main groups. In the "maritime regime", the air masses moved mostly over the sea and just short distances (ca. 100 to 150 km) over land; in the "terrestrial regime", the air masses had moved long distances (ca. 300 to 600 km) over land before reaching the sampling site. The chemical composition of the particles was strongly influenced by the origins of the air masses. Air mass belonging to the maritime regime brought more sea-salt species such as Na(+), Cl(-), and Mg(2+). Air mass belonging to the terrestrial regime carried more K(+) and secondary components like SO(4)(2-), NO(3)(-), and NH(4)(+). Sulfate showed bimodal distribution, peaking both in the fine mode (particle size <0.96 microm) and the coarse mode (particle size >0.96 microm). Nitrate exhibited a bimodal distribution in the terrestrial regime but only a coarse mode in maritime regime. Ammonium displayed a unimodal size distribution, peaking in the fine size range, mainly bound to sulfate and nitrate. In the maritime regime, chloride showed a unimodal distribution, peaking in the coarse size range. In the terrestrial regime, chloride appeared to be bimodal with one peak in the fine mode, reflecting the presence of chloride sources from industries, and another one in the coarse mode, mainly from sea spray. Although in general the air mass trajectories can be grouped into "maritime" and "terrestrial" regimes, the results suggest that air masses reaching Sheffield have been impacted by both maritime and terrestrial sources.
为了表征谢菲尔德市区细颗粒物（PM₁₀）中的水溶性无机成分，2006年10月和11月在一次为期13天的采样活动中，使用低压冲击器（ELPI）采集了不同粒径的气溶胶样本。通过离子色谱法测定了Cl⁻、NO₃⁻、SO₄²⁻和NH₄⁺，并通过电感耦合等离子体质谱法测定了Na⁺、K⁺、Mg²⁺和Ca²⁺。后向轨迹分析表明，气团可分为两大类。在“海洋气团模式”下，气团主要在海洋上空移动，仅在陆地上空短距离（约100至150公里）移动；在“陆地气团模式”下，气团在到达采样点之前已经在陆地上空长距离（约300至600公里）移动。颗粒物的化学成分受气团来源的强烈影响。属于海洋气团模式的气团带来了更多的海盐成分，如Na⁺、Cl⁻和Mg²⁺。属于陆地气团模式的气团携带了更多的K⁺以及SO₄²⁻、NO₃⁻和NH₄⁺等二次成分。硫酸盐呈现双峰分布，在细颗粒模式（粒径<0.96微米）和粗颗粒模式（粒径>0.96微米）中均出现峰值。硝酸盐在陆地气团模式下呈现双峰分布，但在海洋气团模式下仅呈现粗颗粒模式。铵呈现单峰粒径分布，在细粒径范围内达到峰值，主要与硫酸盐和硝酸盐结合。在海洋气团模式下，氯化物呈现单峰分布，在粗粒径范围内达到峰值。在陆地气团模式下，氯化物似乎是双峰的，一个峰值在细颗粒模式中，反映了工业来源的氯化物，另一个峰值在粗颗粒模式中，主要来自海沫。尽管一般来说气团轨迹可分为“海洋”和“陆地”模式，但结果表明到达谢菲尔德的气团受到了海洋和陆地来源的双重影响。
