<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hu SY,Hu M*</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Current challenges of improving visibility due to increasing nitrate fraction in PM2.5 during the haze days in Beijing, China</style></title><secondary-title><style face="normal" font="default" size="100%">ENVIRONMENTAL POLLUTION</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2021</style></year></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://www.sciencedirect.com/science/article/pii/S0269749121016146?via%3Dihub</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">290</style></volume><language><style face="normal" font="default" size="100%">eng</style></language></record></records></xml>