Extending the Capabilities of Single Particle Mass Spectrometry: II. Measurements of Aerosol Particle Density without DMA
Particle density is an important and useful property that is difficult to measure because it usually 5 requires separate instruments to measure two particle attributes. As density measurements are 6 often performed on size-classified particles, they are hampered by low particle numbers, and 7 hence poor temporal resolution. We present here a new method for measuring particle densities 8 using our single particle mass spectrometer, SPLAT. This method takes advantage of the fact 9 that the detection efficiency in our single particle mass spectrometer drops off very rapidly as the 10 particle size decreases below ~125 nm creating a distinct sharp feature on the small particle side 11 of the vacuum aerodynamic size distribution. Thus, the two quantities needed to determine 12 particle density, the particle diameter and vacuum aerodynamic diameter, are known. We first 13 test this method on particles of known composition and find that the densities it yields are 14 sufficiently accurate. We then apply the method to obtain the densities of particles that were 15 characterized during an airborne field campaign. In addition, we show that the distinctive 16 features of the vacuum aerodynamic size distribution can be used to characterize the instrument 17 detection efficiency as a function of particle size. In general, the method presented here reduces 18 complexity and yields information with high temporal resolution while the instrument is 19 collecting routine data on particle size and composition.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 1001453
- Report Number(s):
- PNNL-SA-72410; ASTYDQ; 25623; 25632; KC0302020; KP1701000; TRN: US201102%%21
- Journal Information:
- Aerosol Science and Technology, 45(1):125-135, Vol. 45, Issue 1; ISSN 0278-6826
- Country of Publication:
- United States
- Language:
- English
Similar Records
Extending the Capabilities of Single Particle Mass Spectrometry: I. Measurements of Aerosol Number Concentration, Size Distribution, and Asphericity
Experimental investigation of the effect of inlet particle properties on the capture efficiency in an exhaust particulate filter