On average, the O 3 / CO ra- tio increases with f44 and decreases with f60, indicating in- creased photochemical processing of OA in plumes with at- mospheric aging and ozone production ( Fig....

2020年6月28日 · 研究进一步揭示了不同一次燃烧排放有机气溶胶主要示踪碎片关系，如f55 vs. f57, f44 vs. f60, f44 vs. f43在CV-ToF-ACSM中的变化及其与传统AMS的异同。 将本次实验获得的POA源谱应用于冬季华北平原农村站点的观测研究，结果发现一次有机气溶胶的源解析结果得到显著提高，其中生物质燃烧和燃煤分别贡献总有机气溶胶的32%和21%。 考虑到CV-ToF-ACSM在气溶胶化学组分监测、有机气溶胶来源解析和水溶性有机气溶胶的研究中日益普及，本研究获得 …

2023年8月1日 · The triangle plot of f44 vs. f60 was widely used as a metric to assess the evolution of atmospheric BBOA (Cubison et al., 2011). A value of 0.003 for f60 was recommended as an appropriate value to represent the atmospheric background free of biomass-burning influence (Aiken et al., 2010; Docherty et al., 2018). The f60 ranged from 0.0014 to 0. ...

Download scientific diagram | f44 vs. f60 coloured by ΔOA/ΔCO ratio for (a) close and (b) distant BB periods (vertical black lines refer to the f60 background level of 0.003).

The fractional signals f44 vs f60 of aerosols sampled in this and other studies. Blue and black markers represent the average of FT and BL BBA layers, respectively, for each flight. The oval...

Effect of measurements timescales on f44 (AMS with capture vaporizer-CV) • Essentially no variability observed between 5 and 30 sec switching with CV. • CV enhances f44 compared to Standard Vaporizer. • For squalane, a hydrocarbon (C30H50), negligible 44 signal is observed (f44 < 0.01)…CO2 comes from acid group in particle. 18

The influence of biomass burning emissions can be seen in Fig. 4, which shows the organic fragment ratios f44 vs. f60. The f44 is correlated with the O : C ratio and therefore represents oxygenated organic compounds (considering CO 2 + at the m / z 44 fragment as a proxy), while f60 consists of fragments of levoglucosan and is considered a BB ...

Resolution of 5000 allows for unambiguous identification of isobaric ions at m/z < 100. Goal: apportion signal to all contributing ions, be as quantitative as possible, for as many m/z’s as...

would help in interpreting the discussions of the relative abundances of f44 vs f43 and f44 vs f60. For example, line ï õ On average, the f ð ð contribution increased as combustion developed is stated without an average value on the plot to assess. Attempting to discern averages of …

Although f 60 and f 44 of CV-ACSM and water-soluble BBOA–WBOA have differences compared with those measured by SV-AMS, the evolving trends in f 44 vs. f 60 are similar (Fig. 6). These results suggest that f 44 vs. f 60 can also be used as a good diagnostic for chemical aging of biomass burning aerosols that are measured