Publisher Summary This chapter defines activity of heterogeneous center as some parameter “w” with some positive λ. The choice of the value of w equal to 0 is arbitrary. Every droplet is described by the molecule number v. For the majority of heterogeneous center types, the approximations of nucleation rates are valid during the period of the essential droplets formation. The integral can be taken in the final limits, which allows one to take into account only the finite region of activities as far as an approximation of the total number of heterogeneous centers by the composition of Hevisaid's functions.
V B Kurasov
Nucleation and Atmospheric Aerosols