Abstract
This study evaluates an innovative system that can be used for Near Real-Time Source Apportionment (NRT model) providing results within minutes after the measurements across six Chinese cities: Beijing, Langfang, Shijiazhuang, Xi’an, Wuhan, and Chongqing during 2020–22. The system leverages the AXA instrumental setup (ACSM, Xact, Aethalometer) to integrate high–time-resolution data and provide detailed insights into major particulate matter (PM) sources and their contributions. Secondary PM components dominated across all sites, accounting for up to 66% of the total PM2.5 mass in some cities. Primary sources such as solid fuel combustion contributed approximately 10–30%, while episodic dust events were a major source in Langfang during specific periods. The system’s performance was validated by strong correlations (R2 > 0.82) with results from optimized source apportionment analyses. Furthermore, robustness tests using reduced datasets (two thirds for training and one third for validation) confirmed the system’s reliability and adaptability under dynamic monitoring conditions. In these tests, high correlations with the optimized source apportionment were achieved, indicating the operational reliability of the model. These findings underscore the NRT model’s potential as a critical tool for real-time air quality management, enabling rapid identification of pollution sources and informing timely mitigation strategies to improve urban air-quality.
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Data availability
The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.
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Acknowledgements
This study was supported by the SDC Clean-Air-China Programme (grant number 7F-09802.01.03). K.R.D. acknowledges support by SNSF Ambizione grant PZPGP2_201992.
Funding
This study was supported by the SDC Clean-Air-China Programme (grant number 7F-09802.01.03).
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M.I.M. conceived and designed the study, developed the methodology and software, and performed the data analysis and validation. T.C. contributed to data analysis, validation, and manuscript editing. Q.W., L.Q., M.F., R.K.Y.C., L.D., Y.H., P.K., and J.T. participated in data collection and validation. Y.Ha., Y.C., S.K., Y.W., Y.S., and R.Z. provided resources, supervision, and local project coordination. K.R.D. and J.G.S. contributed to supervision, data interpretation, and manuscript review. J.C. and A.S.H.P. conceived and designed the study, supervised the project, provided funding, and contributed to manuscript revision. All authors discussed the results and contributed to editing and approving the final manuscript.
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Manousakas, M.I., Cui, T., Wang, Q. et al. Evaluation of real-time source apportionment approaches in six Chinese cities using the AXA (ACSM, Xact, Aethalometer) instrumental set-up. Sci Rep (2026). https://doi.org/10.1038/s41598-026-38154-x
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DOI: https://doi.org/10.1038/s41598-026-38154-x
