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491.
The current state of the ecology of the impact regions is outlined. It is argued that the complex of ecosystems situated around a point polluter (an impact region) is an appropriate model for solving several fundamental and applied ecological problems related to the exploration of strong external impacts on biota. Typical methodological errors resulting from insufficient attention to specific features of passive experiments are analysed, and ways to avoid them are proposed. The principles of spatial arrangements of study sites within the impact region and of the selection of experimental and evaluation units are discussed.  相似文献   
492.
Integrated studies on the temperature regime in a limestone outcrop area have been performed, including analysis of the latitudinal trends and dynamics of direct solar radiation input onto slopes of different exposures and the redistribution of temperatures depending on mesotopographic features of the slopes. Assessment of the diversity of ecological conditions in this model landscape has shown that about 3.3% of its area is potentially suitable for the formation of a relict lithophytic floristic assemblage.  相似文献   
493.
An addition of additives to fuel oils prior to combustion is one way of reducing combustible contaminant emissions to the outer air. Reported test results show that some additives improve, moderately, the combustive properties of fuel oils. Combustion is also improved but to a lesser degree, in boiler systems that are deficient in operation and design. Being combustible, polynuclear hydrocarbons emissions would be reduced by use of additives. Other types of additives to reduce slagging and inhibit corrosion from combustion of fuel oils are also available. The cost of using additives is low. Improved additives are required, especially ones to better combustion in the deficient boiler systems. These can be found by research and literature surveys. Their effectiveness and nontoxicity would be confirmed by laboratory and field testing.  相似文献   
494.
A question often asked about analytical diffusion models is “How do the analytical results for calculating pollution concentrations compare with those obtained by statistical techniques?” Miller and Holzworth (1967) have developed a simple analytical diffusion model that yields relative pollution concentrations, x/Q, as a function of afternoon mixing depth, mean transport wind speed, and city size. This analytical model may also be used in reverse to determine apparent afternoon source strengths from observed afternoon pollution concentrations. The apparent source strengths may then be used with the model on independent data to estimate pollution concentrations. It is the purpose of this note to compare results of calculating average afternoon concentrations of oxides of nitrogen (NOx) by use of the Miller-Holzworth model with those obtained from statistical regression equations.  相似文献   
495.
This Report, published as Informative Report No. 7 of the Air Pollution Control Association’s TI-5 Public Utilities Committee, began to move through the 14 step approval procedure of APCA’s Technical Council in February 1964 Comments made by members of the Technical Council were considered in the preparation of the final report. It is now published as representing the best thinking of the Association. It is an extremely timely and informative report.  相似文献   
496.
497.
The importance of fuels combustion was brought into sharp focus recently in a report on air pollution to the United States Senate in which it was stated, “These processes replace usable air with potentially harmful pollutants, and the capability of the atmosphere to disperse and dilute these pollutants—especially in urban areas where people, vehicles, and industries congregate in even greater numbers—is strictly limited.”1 The overwhelming burden of emissions of sulfur compounds, as well as nitrogen compounds and particulate matter in the U. S. today, originates from the burning of coal and fuel oil in stationary combustion sources. Thus, combustion has a large influence on the quality of the atmosphere in most urban areas. The air pollution effects of these contaminants are many and varied and all are objectionable and undesirable. Without a doubt, the most serious air pollution problem in the nation today is that created by the combustion of fossil fuels.  相似文献   
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499.
This annotated bibliography was prepared for the purpose of directing interested persons to some of the more helpful references in the field of air pollution meteorology. It obviously is not a complete listing. The reader who requires more information is directed to the references in the articles listed.  相似文献   
500.
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