On the influence of the vapour substance on the behaviour of an expansion-type condensation nucleus counter

Heterogeneous Nucleation of n-Butanol Vapor on Submicrometer Particles of SiO2 and TiO2

“…Our observation of a S cr smaller than the prediction is consistent with the results of Helsper and Niessner (7). They obtained a Kelvin equivalent diameter 40% greater than the …”

“…Porstendoerfer et al (5) have investigated the nucleation of water vapor on ultrafine Ag and NaCl aerosols and observed a significant dependence of the heterogeneous nucleation process on particle size and chemical composition. Niessner et al (6,7) investigated the effect of surface properties of ultrafine particles on the condensation of water and n-butanol and also observed a strong dependence on particle size and chemical composition; but they obtained a critical supersaturation for the condensation of n-butanol vapor on NaCl and Ag particles smaller than that for perfectly wetted particles. In our previous studies of the nucleation of water vapor on fine aerosols, including SiC, naphthalene, SiO 2 , Al 2 O 3 , TiO 2 , and carbon black from incomplete combustion of diesel fuel, all aerosols except naphthalene induced heterogeneous nucleation better than perfectly wetted particles, in contrast to the measured contact angles, which were all greater than 25° (8,9).…”

Condensation of Supersaturated Water Vapor on Charged/Neutral Nanoparticles of Glucose and Monosodium Glutamate

“…[8] is extended to soluble particles with the following modifications: r a is set to (i) the particle radius for the cases of one and three extrema or (ii) the embryo radius at which the embryo is in a stable equilibrium with the supersaturated vapor for the case of two extrema, and G * is evaluated by Eqs. [5], [6], or [7], respectively. Note that for the case of three extrema, the kinetic prefactor K should also be dependent on each potential barrier and becomes more complicated.…”

Condensation of Supersaturated n-Butanol Vapor on Charged/Neutral Nanoparticles of D-Mannose and L-Rhamnose

“…[8] is extended to soluble particles with the following modifications: r a is set to (i) the particle radius for the cases of one and three extremum(a) or (ii) the embryo radius at which the embryo is in stable equilibrium with the supersaturated vapor for the case of two extrema; and G * is evaluated by Eqs. [5], [6], or [7], respectively.…”

“…, [6] where r k and r a are the largest and the next smaller roots of ∂ G/∂r = 0. (iii) Case 3: Three extrema (two maxima and one minimum) G * is the sum of the Gibbs energy for the formation of an embryo with a diameter in unstable equilibrium with the vapor, r k1 (i.e., first maximum), the Gibbs energy difference between the embryo with a diameter in unstable equilibrium with the vapor, r k2 (i.e., second maximum), and that in stable equilibrium with the vapor, r a (i.e., minimum), and is written as…”