Abstract Indo-Gangetic Plain (IGP) receives emissions from variety of pollutant sources such as post-harvest crop residue burning, vehicles, industries, power plants, and bio-fuel burning. Several studies have documented physical, chemical and optical properties of aerosol over the IGP; however, their oxidative potential (OP) has not yet documented. Present study reports the OP (measured through dithiothreitol (DTT) assay) of soluble particulate matter smaller than 2.5 μm aerodynamic diameter (PM2.5) over Patiala (30.3°N, 76.4°E, 249 m amsl), a semi-urban site located in the IGP, during winter 2014. Volume-normalized OP (range: 1.3–7.2 nmol DTT min−1 m−3, average: 3.8 ± 1.4, 1σ) is found to be ∼3 to 20 times higher, and mass-normalized OP (range: 13-50 pmol DTT min−1 μg−1, average: 27 ± 8, 1σ) is found to be similar or higher than those documented in literature. Further, observed OP is found to depend more on PM2.5 composition rather than mass concentration. Mass fractions of organic carbon (OC), elemental carbon (EC) and water-soluble organic carbon (WSOC) correlate positively whereas that of secondary inorganic aerosol (SIA, sum of the concentrations of SO 4 2 − , NO 3 − and NH 4 + ) correlate negatively with OP μg−1 at considerable significance level (p

中文翻译：

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印度-恒河平原半城市地区环境细气溶胶的氧化潜力

摘要 印度恒河平原 (IGP) 接收来自各种污染源的排放，例如收获后作物残留物燃烧、车辆、工业、发电厂和生物燃料燃烧。几项研究记录了 IGP 上气溶胶的物理、化学和光学特性；然而，它们的氧化电位 (OP) 尚未记录。本研究报告了半城市站点 Patiala (30.3°N, 76.4°E, 249 m amsl) 上小于 2.5 μm 空气动力学直径 (PM2.5) 的可溶性颗粒物的 OP（通过二硫苏糖醇 (DTT) 测定法测量）位于 IGP 中，2014 年冬季。发现体积归一化 OP（范围：1.3–7.2 nmol DTT min-1 m-3，平均值：3.8 ± 1.4, 1σ）高约 3 到 20 倍，质量-归一化 OP（范围：13-50 pmol DTT min−1 μg−1，平均值：27 ± 8，1σ) 被发现与文献中记录的相似或更高。此外，发现观察到的 OP 更多地取决于 PM2.5 的成分而不是质量浓度。有机碳 (OC)、元素碳 (EC) 和水溶性有机碳 (WSOC) 的质量分数呈正相关，而二次无机气溶胶 (SIA，SO 4 2 - 、NO 3 - 和 NH 4 + ) 在相当大的显着性水平 (p