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The kinetics equation is considered for the differential concentration of a single atmospheric aerosol component particles. For the size distribution function, the kinetics equation is obtained under assumption that the function describing an elementary size interval change due to gas-to- particle process doesn't depend on time. The terms in the right side of the equation are due to gas-to-particle conversion and presents the product of the particle growth rate and the particle size derivative of the differential concentration. Under mist the particles' growth rate is determined as the product of three factors: the supersaturation of condensing substance, the function describing particles' volume dependence on air relative humidity and the function of particles size, which is analogically to the growth law in the dry atmosphere. In case of multicomponent aerosol we use the kinetics equations system. The equations of system are related with each other due to coagulation process and redistribution of condensing gas impurities on al aerosol components. It is shown that polymodal approximation is the effective instrument to solve different tasks of multicomponent aerosol kinetics. The possibility to control and aerosol structure and physical- chemical composition is illustrated by help the simple kinetics model of water-soluble and soot aerosol at the stationary approximation. Coagulation process is considered by analogy with gas-to-particle conversion processes. Therefore, the growth rate of particle volume and size is presented as the sum of two terms. The second term allows to take into account coagulation process approximately for a wide range of particle size change. For soot, water-soluble particles, the particular cases of growth law are considered. To determine soot volume part in aerosol mixed particles the analytical method is suggested.
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