Dilution, pollution solved

Selection of pollution control methods is generally based on the need to control ambient air quaUty in order to achieve compliance with standards for critetia pollutants, or, in the case of nonregulated contaminants, to protect human health and vegetation. There are three elements to a pollution problem a source, a receptor affected by the pollutants, and the transport of pollutants from source to receptor. Modification or elimination of any one of these elements can change the nature of a pollution problem. For instance, tall stacks which disperse effluent modify the transport of pollutants and can thus reduce nearby SO2 deposition from sulfur-containing fossil fuel combustion. Although better dispersion aloft can solve a local problem, if done from numerous sources it can unfortunately cause a regional one, such as the acid rain now evident in the northeastern United States and Canada (see Atmospheric models). References 3—15 discuss atmospheric dilution as a control measure. The better approach, however, is to control emissions at the source. 

The primary cause of acid rain is industrial and automotive pollution. Each year in industrialized countries, large power plants and smelters that burn sulfur-containing fossil fuels pour millions of tons of sulfur dioxide (S02) gas into the atmosphere, where some is oxidized by air to produce sulfur trioxide (S03). Sulfur oxides then dis-l solve in rain to form dilute sulfurous acid and sulfuric acid ... 

We can also solve this problem by the dilution calculation we used above, in which the pollutant flow is diluted by the water flow. Hence,... 

Ion trap mass spectrometers demonstrate complete apphcabihty to these alkali metal ion attachment reactions due to their in-time confinement capability, which provides a high efficiency for alkali ion attachment reactions compared to conditions in a classical quadrupole ion source. This method should be of general interest to those needing to solve problems involving organic pollutants, samples diluted in a matrix, pyrolytic products and samples that are of environmental concern, in situations where classical chemical ionization techniques are not always satisfactory due to their structure-dependent responses. One of the main advantages of sodium ion attachment reactions for such analysis is that the ionization conditions are not pressure dependent, unlike conventional Cl ionization processes. 

The problem of treating atmospheric pollution is still in its infancy. As late as the 60s, the atmosphere was still considered a limitless sump in which noxious fumes created by the combustion of fuels would be diluted to harmless proportions. Consequently, when large power plants first were found to contaminate the immediate surroundings, the designers solved the problem by building very tall smokestacks. This solved the local problem, but, as the information in this conference will show, the noxious products were not diluted to harmless proportions. 

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