Aerosol particles chemical constitution

Measured size distributions of salt particles are monomodal and can by parameterized by the power law, with the index varying within 0.97-4.2 (average 2.3-2.6). The density of MSA particles is close to 2.35 — 2.40 g/m The spatial distribution of Cn MSA (r > 1 pm) for different regions of the world ocean can be illustrated by the following values in the Pacific Ocean Cn = (1.2-1.5) cm in the Indian Ocean (0.9-1.0) cm" near the Australian coastline 0.4 cm near the boundaries of the Antarctic ice sheet (1.8-2.1) cm" and near the Black Sea coastline (0.32-1.93) cm" [8]. The vertical distribution of Cn MSA has some specific features. A maximum of Cn distribution is often observed at altitudes of several hundred meters (apparently, because of a decrease in the Cn MSA near the water surface, resulting from the capture of salt particles by sea waves). At altitudes 2-3 km the value of Cn MSA constitutes < 1 % of the total Cn value, which is explained by the cloud filter . However, over land, near the coastline, at an altitude of 3 km, Cn MSA is somewhat higher than at the same level over the sea surface. This is connected with a more intensive turbulence over land. In general, sea-salt aerosol particles have to be chemically composed of dried sea water 88.7% chlorides, 70.8% sulfates, 0.3% carbonates, and 0.2% other salts. 

Priedlander SK (2000) Smoke, Dust, and Haze Fundamentals of Aerosol Dynamics, Second Edition, Oxford University Press, New York Guido Lavalle G, Carrica PM, Clausse A, Qazi MK (1994) A bubble number density constitutive equation. Nucl Engng Des 152 213-224 Hagesaether L, Jakobsen HA, Svendsen HF (1999) Theoretical Analysis of Fluid Particle Collisions in Turbulent Flow. Chem Eng Sci 54(21) 4749-4755 Hagesaether L, Jakobsen HA, Hjarbo K, Svendsen HF (2000) A Coalescence and Breakup Module for Implementation in CFD-codes. Computer-Aided Chemical Engineering 8 367-372... 

The preceding examples show various ways in which solid or liquid inorganic particulates are formed in polluted urban air hy chemical reactions. Such reactions constitute the most important general processes for the formation of aerosols, particularly the smaller particles in air of Asian cities. 

As part of the biogeochemical cycle, the injection of iodine-containing gases into the atmosphere, and their subsequent chemical transformation therein, play a crucial role in environmental and health aspects associated with iodine - most importandy, in determining the quantity of the element available to the mammalian diet. This chapter focuses on these processes and the variety of gas- and aerosol-phase species that constitute the terrestrial iodine cycle, through discussion of the origin and measurement of atmospheric iodine in its various forms ( Sources and Measurements of Atmospheric Iodine ), the principal photo-chemical pathways in the gas phase ( Photolysis and Gas-Phase Iodine Chemistry ), and the role of aerosol uptake and chemistry and new particle production ( Aerosol Chemistry and Particle Formation ). Potential health and environmental issues related to atmospheric iodine are also reviewed ( Health and Environment Impacts ), along with discussion of the consequences of the release of radioactive iodine (1-131) into the air from nuclear reactor accidents and weapons tests that have occurred over the past half-century or so ( Radioactive Iodine Atmospheric Sources and Consequences ). 

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