Classical Homogeneous Nucleation Theory

In the past half-decade, extensive studies have focused on aerosol nucleation in aircraft exhaust plumes [79]. This interest has brought attention to the formation of volatile aerosols that might eventually evolve into cloud condensation nuclei [80], Measurements of ultrafine particles reveal remarkably high abundances in jet wakes at very early times (within 1 second of emission) (e.g., [81]). As in the background atmosphere, the classical homogeneous nucleation theory has been applied to explain the number and size distribution of these volatile microscopic particles [82,83], However, while achieving some initial success, the theory has not been able to explain more recent, detailed observations. 

Classical homogeneous nucleation theory gives a nucleation rate that depends essentially on the crystal-melt surface free energy a. In order to make predic-... 

Classical homogeneous nucleation theory is widely employed to describe the formation of new particles in the atmosphere (Pruppacher and Klett 1997 Seinfeld and... 

Equation (11.47) is the classical homogeneous nucleation theory expression for the nucleation rate. It is the expression that we will use to predict nucleation rates of different pure substances as a function of saturation ratio. 

CLASSICAL HOMOGENEOUS NUCLEATION THEORY CONSTRAINED EQUILIBRIUM APPROACH... 

Experimental Evaluation of Classical Homogeneous Nucleation Theory... 

According to classical homogeneous nucleation theory, the nucleation rate depends exponentially on the energy ()of forming a critical size nucleus as follows ... 

The main concern of the classical homogeneous nucleation theory has been a thermodynamic description of the initial stage of nucleation from embryo to nucleus with a little larger size over the critical one (Seinfeld 1986, Pruppacher and Klett 1997, Seinfeld and Pandis 1998, Kulmala et al. 2000). The change of the free enthalpy of the cluster is at first positive because the decrease of entropy is initially larger (regular structure formation) than the decrease in enthalpy ... 

Warneck, P. (2000) Chemistry of the natural atmosphere. Academic Press, New York, 969 pp Warneck, P. (2003) In-cloud chemistry opens pathway to the formation of oxalic acid in the marine atmosphere. Atmospheric Environment 37, 2423-2427 Wasai, K., G. Kaptay, K. Mukai and N. Shinozaki (2007) Modified classical homogeneous nucleation theory and a new minimum in free energy change 1. A new minimum and Kelvin equation. Fluid Phase Equilibria 254, 67-74 Waterman, L. S. (1983) Comments on The Montsouris series of carbon dioxide concentration measurements, 1877-1910 by Stanhill . Climate Change 5, 413-415... 

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