Assessment of wire and tube penetration theories using a cluster aerosol

Filtration of Unipolarly Charged Aerosol Nanoparticles with an Initially Discharged Dielectric Screen

“…[1]- [4] above, gives quite accurate predictions for particle size down to 0.6 nm in the case of wire screens (5,6). The preliminary experiments with a wire screen were done to check the validity of our single DMA sizing measurements.…”

“…The diffusional penetration model summarized above has been shown to be correct for particle size down to 0.6 nm and for aerosol particles in any state of charge (positive, negative or neutral) (5,6).…”

A Chamber Study of Secondary Organic Aerosol (SOA) Formed by Ozonolysis of d-Limonene in the Presence of NO

“…The chamber was described by Ramamurthi et al (1990) and Hopke et al (1992) and has been used in a number of prior studies of ozone-terpene reaction studies (Chen and Hopke, 2009a, b;2010;Liu and Hopke, 2014). The environment in the chamber was dark.…”

Deposition of Aerosol Particles below 10 nm on a Mixed Screen-Type Diffusion Battery

“…GSAs were used in several studies of radon decay product behavior (e.g., Strong, 1988;Ramamurthi and Hopke, 1989;Ramamurthi et al, 1990;Winklmayr et al, 1990;Li and Hopke, 1991;Hopke et al, 1992;Solomon and Ren, 1992;Cheng et al, 2000). The Cheng-Yeh wire screen penetration theory in the molecular cluster size range was confirmed the validity by Ramamurthi et al (1990) using a well-defined and radioactive 218PoO x cluster aerosol, highly disffusive D avg = 0.078 ± 0.003 cm 2 /s (dp ≈ 0.6 nm). An assessment of wire screen penetration theory for two low mesh number wire screens indicated good agreement with the diffusion theory within the domain of Re f < 1 (Scheibel and Porstendörfer 1984;Cheng et al, 1990).…”

“…A special type of diffusion battery for measuring the particle size of aerosols is the so called graded screen array (GSA) and was first developed by Holub and Knutson (1987) in the 1980s, in which several screens differing in their geometric characteristics (wire diameter, screen thickness, opening and solid volume fraction) are arranged in series within a filter holder (e.g., Solomon and Ren, 1992). GSAs were used in several studies of radon decay product behavior (e.g., Strong, 1988;Ramamurthi and Hopke, 1989;Ramamurthi et al, 1990;Winklmayr et al, 1990;Li and Hopke, 1991;Hopke et al, 1992;Solomon and Ren, 1992;Cheng et al, 2000). The Cheng-Yeh wire screen penetration theory in the molecular cluster size range was confirmed the validity by Ramamurthi et al (1990) using a well-defined and radioactive 218PoO x cluster aerosol, highly disffusive D avg = 0.078 ± 0.003 cm 2 /s (dp ≈ 0.6 nm).…”