Beijing Institute of Petrochemical Technology

TL;DR: In this paper, the authors provide a first view of vulnerable informal economy after the blows from COVID-19, using transaction-level business data of around 80 million offline micro businesses (OMBs) owners from the largest Fintech company in China and employing machine learning method for causal inference.

TL;DR: In this article, pyrophoric active ferrous sulfide sample was synthesized in laboratory and the synthetic sample was studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) combined with energy dispersive spectrometer (EDS), electron probe microanalysis (EPMA), and thermal analysis (TA).

TL;DR: In this article , the authors provide a first view of vulnerable informal economy after the blows from COVID-19, using transaction-level business data of around 80 million offline micro businesses (OMBs) owners from the largest Fintech company in China and employing machine learning method for causal inference.

TL;DR: Primary OA was the dominant species, as well as increased with the pollution level, implicating VOCs and NOx should be controlled to relieve the secondary OA pollution.