Atmospheric water transport, effects

Chloroform exists almost entirely as a vapor in the atmosphere. Chloroform is effectively eliminated by wet deposition but can reenter the atmosphere following subsequent volatilization. Long-range transport within the atmosphere is possible. Chloroform is eliminated from surface waters primarily by volatilization. Chloroform is not expected to substantially adsorb to organic matter in surface water. Chloroform does not appreciably bioconcentrate in higher aquatic organisms. Chloroform has a moderate potential to concentrate in some aquatic plants. 

The reactants for aqueous-phase atmospheric reactions are transferred to the interior of cloud droplets from the gas phase by a series of mass transport processes. We would like to compare the rates of mass transport in the gas phase, at the gas-water interface, and in the aqueous phase in an effort to quantify the mass transport effects on the rates of aqueous-phase reactions. If there are no mass transport limitations, the gas and aqueous phases will remain at Henry s law equilibrium at all times. Our objective will be to identify cases where mass transport limits the aqueous-phase reaction rates and then to develop approaches to quantify these effects. 

Hazardous chemical spills may have adverse effects on natural water systems, tlie land enviromnent, and whole ecosystems, as well as tlie atmosphere. Major spills evolve from accidents (see Chapter 6) tliat somehow damage or rupture vessels, tank cars, or piping used to store, sliip, or transport liazardous materials. In such cases, the spills must be contained, cleaned up, and removed as quickly and effectively as possible. 

Variations in solution composition throughout a test should be monitored and, if appropriate, corrected. Variations may occur as a result of reactions of one or more of the constituents of the solution with the test specimen, the atmosphere or the test vessel. Thus, it is important that the composition of the testing solution is what it is supposed to be. Carefully made-up solutions of pure chemicals may not act in the same way as nominally similar solutions encountered in practice, which may, and usually do, contain other compounds or impurities that may have major effects on corrosion. This applies particularly to artificial sea-water, which is usually less corrosive than natural sea-water. This subject is discussed in detail in a Special Technical Publication of ASTM, and tests with natural, transported and artificial sea-water have been described . Suspected impurities may be added to the pure solutions in appropriate concentrations or, better still, the testing solutions may be taken directly from plant processes whenever this is practical. 

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