Application of Single-Particle Mass Spectrometer to Obtain Chemical Signatures of Various Combustion Aerosols

Abstract

A single-particle mass spectrometer (SPMS) with laser ionization was constructed to determine the chemical composition of single particles in real time. The technique was evaluated using various polystyrene latex particles with different sizes (125 nm, 300 nm, 700 nm, and 1000 nm); NaCl, KCl, MgCO3, CaCO3, and Al2O3 particles with different chemical compositions; an internal mixture of NaCl and KCl; and an internal mixture of NaCl, KCl, and MgCl2 with different mixing states. The results show that the SPMS can be useful for the determination of chemical characteristics and mixing states of single particles in real time. The SPMS was then applied to obtain the chemical signatures of various combustion aerosols (diesel engine exhaust, biomass burning (rice straw), coal burning, and cooking (pork)) based on their single-particle mass spectra. Elemental carbon (EC)-rich and EC-organic carbon (OC) particles were the predominant particle types identified in diesel engine exhaust, while K-rich and EC-OC-K particles were observed among rice straw burning emissions. Only one particle type (ash-rich particles) was detected among coal burning emissions. EC-rich and EC-OC particles were observed among pork burning particles. The single-particle mass spectra of the EC or OC types of particles differed among various combustion sources. The observed chemical signatures could be useful for rapidly identifying sources of atmospheric fine particles. In addition, the detected chemical signatures of the fine particles may be used to estimate their toxicity and to better understand their effects on human health.

Mathieu-Hill Equation Stability Analysis for Trapped Ions. Anharmonic Corrections for Nonlinear Electrodynamic Traps

“…Ion dynamics in a Paul (or RF) trap is characterized by a Mathieu-Hill type equation [20,39]. The Paul trap apparatus [in case of both 2D linear ion traps (LIT) and 3D versions] has been developed and refined for high finesse quantum engineering experiments, high precision spectroscopy [40,41], along with classical mass spectrometry (MS) [42][43][44][45][46][47] or chemical analysis [48], including the detection of aerosols and chemical warfare [49][50][51][52][53][54][55][56][57]. Besides, ion traps also enable exceptional control in preparing and manipulating atomic quantum states [58][59][60][61][62][63], which is why their wide area of applications also includes quantum logic [64][65][66][67][68], quantum sensing [69][70][71][72], quantum metrology [73,74] and even time fractals [75] or time crystals [76].…”

Mathieu–Hill Equation Stability Analysis for Trapped Ions: Anharmonic Corrections for Nonlinear Electrodynamic Traps

“…Ion dynamics in a Paul (or RF) trap [26,33] is characterized by a MH-type equation [21,34]. The Paul trap apparatus [in the case of both 2D linear ion traps (LITs) and 3D versions] has been developed and refined for high-finesse quantum engineering experiments, high-precision spectroscopy [35,36], classical mass spectrometry (MS) [37][38][39][40][41][42] and chemical analysis [43], including the detection of aerosols and chemical warfare [44][45][46][47][48][49][50][51][52].…”