Aerosol fog

Anastasio, C., B. C. Faust, and C. J. Rao, Aromatic Carbonyl Compounds as Aqueous-Phase Photochemical Sources of Hydrogen Peroxide in Acidic Sulfate Aerosols, Fogs, and Clouds. 1. Non-Phenolic Methoxybenzaldehydes and Methoxyacetophe-nones with Reductants (Phenols), Environ. Sci. Techno ., 31, 218-232 (1997). 

Faust, B. C., K. Powell, C. J. Rao, and C. Anastasio, Aqueous-Phase Photolysis of Biacetyl (an a-Dicarbonyl Compound) A Sink for Biacetyl and a Source of Acetic Acid, Peroxyacetic Acid, Hydrogen Peroxide, and the Highly Oxidizing Acetylperoxyl Radical in Aqueous Aerosols, Fogs, and Clouds, Atmos. Environ., 31, 497-510 (1997). 

The principles of insect control by thermal aerosol fogs, developed from idea to practical application in five years, are reviewed. Two large scale experiments, one indoor and one outdoor, carried out by the New York State Science Service are explained in detail along with their chemical and physical data. Characteristics of a special oil developed for fogging are also given. 

The readiness with which many organizations and individuals collaborated with each other and with the Science Service made possible tests on an imusually large scale, and the principle of insect control by thermal aerosol fogs has been developed and perfected rapidly. It has taken only 5 years to progress from a mere idea to practical use with helicopters and jet engines. 

Aerosol fogs as used in entomological work are of three general types an oil solution of the insecticide dispersed as microscopic droplets by a liquefied gas propellant, usually Freon a mist or fog produced by mechanical means a fog produced by means of a thermal aerosol fog generator. 

For volume production of an aerosol fog of small particle size, on a large scale (suited to indoor use), the thermal aerosol fog generators appear to be very efficient. The Science Service experiments were mostly with this type. Two principal varieties have been developed. One discharges the insecticide solution or suspension as a relatively coarse spray into a jet of superheated steam delivered by a flash boiler of the tubular coil t3rpe. The other discharges that insecticide solution or suspension as a relatively coarse spray into a blast of hot gas emerging from a combustion chamber. The temperature is regulated by the controlled admixture of cold air. 

Aerosols, fog and smog, foams, water purification and sewage treatment cloud seeding and clean room technology (see also Vignettes 1.1 and VIII)... 

None (all gases are infinitely Liquid aerosol (fog, mist, Solid aerosol (smoke,... 

Gas Liquid Aerosol Fog, aerosol sprays, some air poUutants... 

Liquid Gas Liquid aerosol Fogs, mist, clouds. 

Less straightforward is the definition of the source term the initial conditions of cloud mass, temperature, concentration, and dimensions (height, width). This is a function of the discharge type (spill or pressurized jet), the rate and duration (or mass if a puff) of release, temperamre before and after any flash, the flash fraction, aerosol/fog formation, and initial dilution. Some models include source term models which may not be apparent to the user. 

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