TY - JOUR ID - 10.1016/j.jes.2021.09.036 TI - Chemical composition of different size ultrafine particulate matter measured by nanoparticle chemical ionization mass spectrometer AU - Weigang Wang AU - Yan Chen AU - Lei Li AU - Li Zhou AU - Xubing Du AU - Mingyuan Liu AU - Maofa Ge VL - 34 IS - 4 PB - SP - 434 EP - 443 PY - JF - Journal of Environmental Sciences JA - J. Environ. Sci. UR - http://www.jesc.ac.cn/jesc_en/ch/reader/view_abstract.aspx?file_no=S1001074221004083&flag=1 KW - Corresponding author.;Nanoparticle;Chemical composition;Chemical ionization;Mass spectrometer AB - New particle formation (NPF) is the primary source of nanoparticles and contributes a large number of concentrations of cloud condensation nuclei. In recent years, field campaigns and laboratory experiments have been conducted to promote cognition of the mechanism for NPF and its following growth processes. The chemical composition measurement of nanoparticles could help deepen understanding of the initial step of particulate matter formation. In this work, we developed a nanoparticle chemical ionization mass spectrometer to measure nanoparticles' chemical compositions during their initial growth stage. Meanwhile, a non-radioactive ion source was designed for aerosol charging and chemical ionization. Time of flight mass spectrometer coupled with integrated aerosol size selection and collection module would guarantee the picogram level detection limit and high-resolution ability to measure the matrix of ambient samples. The performance of this equipment was overall evaluated, including the transmission efficiency and collection efficiency of custom-built nano differential mobility analyzer, chemical ionization efficiency, and mass resolution of the mass spectrometer. The high sensitivity measurement of ammonium sulfate and methylammonium sulfate aerosols with diameters ranging from 10 to 25 nm could guarantee the application of this instrument in the ambient measurement. ER -