Sulfur (S) and sulfate (SO4 2- ) in fine particulate matter (PM2.5 ) are monitored by the Interagency Monitoring of Protected Visual Environments (IMPROVE) network at remote and rural sites across the United States. Within the IMPROVE network, S is determined from X-ray fluorescence (XRF) spectroscopy from a Teflon filter, and SO4 2- is determined via ion chromatography (IC) from a nylon filter. Differences in S and SO4 2- estimates may indicate the presence of organosulfur (OS) species or biases between sampling and analytical methods. To reduce potential biases, an inductively coupled plasma-optical emission spectroscopy (ICP-OES) method was developed to allow for analysis of SO4 2- and S from a single filter extract. Sulfur (ICP-OES) and SO4 2- (IC) estimates from 2016 IMPROVE filters correlated strongly, suggesting that, on average, ICP-OES accurately estimated S. However, observed differences between slopes suggested the presence of water-soluble OS species, especially during summer. Organosulfur species are important indicators of secondary organic aerosols formed through reactions of biogenic and anthropogenic pollutants and can be quantified through laboratory techniques such as reverse-phase liquid chromatography (RPLC) or hydrophilic liquid interaction chromatography (HILIC) coupled to electrospray ionization-high-resolution tandem mass spectrometry (RPLC/ESI-HR-MS/MS and HILIC/ESI-HR-MS/MS, respectively), and field techniques using Aerodyne aerosol mass spectrometry (AMS). However, these methods are costly and introduce relatively large uncertainties when scaled for large networks such as IMPROVE. The method described in this report provides an inexpensive complement to XRF, which measures total S (insoluble and water-soluble S) to estimate water-soluble S and OS concentrations in PM.

中文翻译：

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用 ICP-OES 分析尼龙过滤器上细颗粒质量的总硫

细颗粒物 (PM2.5) 中的硫 (S) 和硫酸盐 (SO4 2- ) 由美国各地偏远和农村地区的受保护视觉环境机构间监测 (IMPROVE) 网络监测。在 IMPROVE 网络中，S 由来自聚四氟乙烯过滤器的 X 射线荧光 (XRF) 光谱测定，而 SO4 2- 由来自尼龙过滤器的离子色谱 (IC) 测定。S 和 SO4 2- 估计值的差异可能表明存在有机硫 (OS) 种类或采样和分析方法之间的偏差。为了减少潜在偏差，开发了一种电感耦合等离子体光发射光谱 (ICP-OES) 方法，以分析来自单个过滤器提取物的 SO4 2- 和 S。来自 2016 年 IMPROVE 过滤器的硫 (ICP-OES) 和 SO4 2- (IC) 估计值具有很强的相关性，这表明平均而言，ICP-OES 准确估计了 S。然而，观察到的斜坡之间的差异表明存在水溶性 OS 物种，尤其是在夏季。有机硫物种是生物和人为污染物反应形成的二次有机气溶胶的重要指标，可以通过反相液相色谱 (RPLC) 或亲水液体相互作用色谱 (HILIC) 等实验室技术与电喷雾电离 - 高分辨率进行量化串联质谱（分别为 RPLC/ESI-HR-MS/MS 和 HILIC/ESI-HR-MS/MS），以及使用 Aerodyne 气溶胶质谱 (AMS) 的现场技术。然而，这些方法成本高昂，并且在针对大型网络（如 IMPROVE）进行扩展时会引入相对较大的不确定性。