Inorganic aerosol

Strengths 1. Effective against the complete range of indoor air pollutants including organic- bio-aerosols, VOCs, odors and carbon monoxide 2. New advanced technology 3. Inexpensive material 4. Easy to manufacture. Weaknesses 1. Unable to remedy inorganic aerosols 2. Low clean air delivery rate (< 100 cfm) 3. Produces carbon dioxide. 

FORMATION OF SECONDARY INORGANIC AEROSOLS IN PHOTOCHEMICAL SYSTEMS... 

FIGURE 3-2S Diurnal profiles of nitrogen compounds, Pasadena, California, July 25, 1974. NO, NO, O, and PAN in ppm inorganic aerosol nitrates in Mg/m Data from Grosjean and Friedlander and Hanst et o/. ... 

John, W., S. M. Wall, J. L. Ondo, and W. Winklniayr, Modes in the Size Distributions of Atmospheric Inorganic Aerosol, Atmos. Environ., 24A, 2349-2359 (1990). 

Wexler, A. S., and J. H. Seinfeld, Second-Generation Inorganic Aerosol Model, Atmos. Environ., 25A, 2731-2748 (1991). 

Sulphates (SO42 ), ammonium (NH4+) and nitrates (NO3 ) are the main secondary inorganic aerosol ions as they account for about two thirds of the total ionic mass in PMj and for about 50% in PM10 in Athens [21], These ions represent two different major source categories fuel combustion and vehicular circulation. Theodosi et al. [21] studied the spatial variability of these ions in 2 sites within GAA Lykovrisi (LYK) and Goudi (GOU). LYK is a moderately populated municipality, in the northern part of the GAA, 10 km from the city centre GOU is located... 

The chemical composition of PM10 shows a considerable conformity in these countries. Always, secondary inorganic aerosols (SIA) are the major constituent ( 40%) followed by the carbonaceous compounds ( 25%). Contributions of sea salt and mineral dust vary between 10% and 15% depending on presence and distance of respective sources. The unidentified mass is some 15% indicating that the composition of PM10 in this region is fairly well known. 

Weijers EP, Sahan E, Ten Brink HM, Schaap M, Matthijsen J, Otjes RP, Van Arkel F (2010) Contribution of secondary inorganic aerosols to PM10 and PM2.5 in the Netherlands measurements and modelling results. PBL Report 500099006, Bilthoven, the Netherlands... 

Nenes A, Pandis SN, Pilinis C (1998) ISORROPIA a new thermodynamic equilibrium model for multiphase multicomponent inorganic aerosols. Aquat Geochem 4 123-152... 

The first section of this chapter is a review of fundamental chemical thermodynamic principles focusing on the chemical potential of species in the gas, aqueous, and solid phases. Further discussion of fundamentals of chemical thermodynamics can be found in Denbigh (1981). Chemical potentials form the basis for the development of a rigorous mathematical framework for the derivation of the equilibrium conditions between different phases. This framework is then applied to the partitioning of inorganic aerosol components (sulfate, nitrate, chloride, ammonium, and water) between the gas and particulate phases. The behavior of organic aerosol components will be discussed in Chapter 14. 

Solutions of Electrolytes Most of the inorganic aerosol components dissociate on dissolution for example, NH4NO3 dissociates forming NHj and NOJ. The concentration of each ion in the aqueous solution is traditionally expressed on the molality scale and the chemical potential of each ion in a NH4NO3 solution is... 

Nenes, A., Pilinis, C., and Pandis, S. N. (1998) ISORROPIA A new thermodynamic model for multiphase multicomponent inorganic aerosols, Aquatic Geochem. 4, 123-152. 

Wexler, A., and Hasegawa, S. (1954) Relative humidity-temperature relationships of some unsaturated salt solutions in the temperature range 0 to 50°C, J. Res. Nat. Bur. Std. 53, 19-26. Wexler, A. S., and Seinfeld, J. H. (1991) Second-generation inorganic aerosol model, Atmos. Environ. 25A, 2731-2748. 

Geochemical Aspects of Inorganic Aerosols near the Ocean-Atmosphere Interface... 

Sources contributing to the composition of inorganic aerosols near the ocearir-atmosphere interface are the oceans themselves, continental dust, volcanic ash, atmospheric production of particulates, and, to lesser extents, human activity and extraterrestrial inputs. Characteristic elements and elemental ratios can be used to determine some of these sources and detect ion fractionation at the sea-air interface. Rain water chemistry is not always simply related to that of the marine aerosol. 

Inorganic aerosols near the ocean-atmosphere interface are composed of both salt and dust. The source of the dust is the continents. This is indicated by analyses that show the elements present in proportions close to those found for average crustal rocks. Further evidence is obtained from mineralogical investigation. Dust over the equatorial Atlantic has been found to originate in Africa, and dust in the South Pacific was traced to Australia. Little is known about the chemistry of aerosol dusts over the oceans. Significant changes in the dust component may occur... 

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