[Comparative PM Pollution Characteristics and Sources in the Autumn and Winter of 2016-2021 in Handan City].

In 2018, the State Council issued the Three-year Action Plan for Winning the Blue Sky Defense War （Blue Sky Defense War）. To study the characteristics and sources of PM pollution in the early stage （first stage）, middle stage （second stage）, and late stage （third stage） of the Blue Sky Defense War in Handan City in autumn and winter, PM samples were collected in the autumn and winter from 2016 to 2021. Based on the concentration data of eight water-soluble ions, EC, and OC the source analysis was performed using the positive definite matrix factorization model, backward trajectory, and potential source contribution factor （PSCF） analysis.

Characterization of PM Carbonaceous Components in a Typical Industrial City in China under Continuous Mitigation Measures.

The goals of the "dual carbon" program in China are to implement a series of air pollution policies to reduce the emission of carbon-bearing particulate matter (PM). Following improvements in the reduction in carbon emissions in Handan City, China, fine particulate matter (PM) was collected in the winters from 2016 to 2020 to characterize the concentrations and sources of carbonaceous components in PM. Trend analysis revealed that both organic carbon (OC) and elemental carbon (EC) concentrations significantly decreased.