On the impact of accessible surface and surface energy on particle formation and growth from the vapour phase

Emission Characteristics of Ultrafine Particles and Volatile Organic Compounds in a Commercial Printing Center

“…3 C as compared to normal average room temperature of 22 C. Under these favorable conditions, it is likely that there was an increase in the rate of vapor-toparticles formation, that is, secondary aerosol formation. 19 Similar results were reported recently by Fadeyi et al 18 and also by Zurami et al 20 in their study on secondary organic aerosol formation in indoor environments. They found that when recirculation rates were decreased in their environmental chambers, particle number concentrations in the size range of 20-30 nm were increased.…”

“…As shown in Figure 5a and b, there was no significant correlation between BC concentration and UFPs in the size range of 5.6-50 nm (r S ¼ À0. 19) and a modest correlation in the size range of 50-100 nm (r S ¼ 0.33) at P ¼ 0.05. However, there was a strong correlation with fine particles in the size range of 100-560 nm (r S ¼ 0.82), as shown in Figure 5c.…”

Particle generation in pulsed plasmas

“…primary particle size, aggregate size, and structure. It is important to note that particle generation and growth are confined to the plasma quench and do actually not take place in the plasma itself, where it is too hot for high supersaturations to occur, such as required to initiate particle formation and growth from the vapour phase [22,23]. Plasma propagation and particle synthesis therefore happen to be separate events in terms of time and/or space.…”

Modelling titania formation at typical industrial process conditions: effect of surface shielding and surface energy on relevant growth mechanisms

“…Achievements with respect to considering structure-related aspects have been realised as well and refer to taking the formation of primary particles into account (e.g. Kruis et al, 1993), to considering the evolution of the fractal dimension along process time (Rosner and Pyykönen, 2002;Artelt et al, 2003) and to accounting for surface shielding in processes involving surface-related growth mechanisms (Artelt et al, 2005). The number of growth mechanisms included in aerosol generation simulations has also grown steadily: Early modelling approaches typically incorporated just a limited set of mechanisms, such as coagulation and sintering (Koch and Friedlander, 1990) or nucleation from a supersaturated vapour and condensation (Panda and Pratsinis, 1995), but have, as in the case of simulating TiO 2 generation and growth, meanwhile been complemented by additionally referring to surface reaction (e.g.…”

“…Jain et al, 1997;Pratsinis and Spicer, 1998). Recently, Artelt et al (2005) also included nucleation from a supersaturated vapour and condensation in addition to chemical reaction, surface reaction, agglomeration and sintering in a model on TiO 2 generation and growth. This becomes important in the presence of a thermodynamic barrier to the formation of new particles, which is typical for a majority of industrially relevant process conditions.…”