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911.
Three different recording analyzers for sulfur dioxide were operated in parallel under field conditions. Manual sampling for sulfur dioxide using the West-Gaeke procedure supplemented the instrumental evaluation tests. Two of the analyzers were of the continuous-flow type. These were found to give markedly higher readings for SO2 in the atmosphere (in some cases as much as threefold) than did the other recorder which was sequential-batch or the West-Gaeke manual method.  相似文献   
912.
913.
It has become increasingly apparent that there exists a need for evaluating the well-being of embryos subjected to chronic doses of CO during gestation. Baily1 and Hadden,2 for example, have reported that maternal cigarette smoking resulted in a significant decrease in infant birth weight. It is obvious, however, that the presence of other pharmacologically toxic substances in cigarette smoke besides carbon monoxide may have been significant. A problem in using the developing mammalian embryo as a model for studying the effects of such agents is that the physiological responses of the mother may afford some measure of protection to the developing fetus. This is not the case in oviparous development because there is no connection between mother and embryo.  相似文献   
914.
On June 18, 19, and 20, 1970, two aircraft, a rawinsonde, two pibal stations, and four ground stations provided simultaneous samples of total oxidant, temperature, and winds up to 8000 ft in an area extending from Santa Monica, Calif., east to Redlands and north across the San Bernardino Mountains. It was shown that photochemical oxidant formed in the marine layer is vented up the slopes and over the crest of the San Bernardino Mountains during the day. Layers of high oxidant concentrations were detected above the inversion base, suggesting that some pollution is vented up the slopes and subsequently advected back to the south. The diurnal changes in the temperature inversion also contribute to the high concentration found above the inversion base. These processes result in multi-layers of pollution. The study suggests that oxidant air pollution is transported up to 80 mi to forested mountains, where severe damage to conifer species has been documented.  相似文献   
915.
Concern for the biological and ecological effects of heated water has resulted in legal actions that will prevent power companies from dumping the waste heat from the majority of their new generating units into rivers and lakes. Many nuclear- and fossil-fueled plants now under construction, and even some now online, are being required to change from once-through cooling systems to other methods, such as wet cooling towers, cooling ponds, and spray canals, despite higher costs and lower thermal efficiencies. Yet, these alternate cooling procedures are not without their own environmental problems.

The primary weather change due to once-through cooling on a large water body is a small local increase in fogginess at the plant outfall. But the relative probability of significant local meteorological effects is much higher with alternate cooling procedures, since these reduce the area of heat and moisture transfer. It is therefore concluded that, from a meteorological point of view, the least undesirable way to dispose of waste heat is by using once-through cooling on large water bodies.  相似文献   
916.
It has been amply demonstrated that there are reasons for improving the collection of fine participates. Some areas of research and development which may prove fruitful in extending fabric filter capabilities have been suggested.  相似文献   
917.
For years educators have been striving for vocational realism in the classroom, that is, an in vivo work training program. Drawbacks to this system, however, have been student attitudes and conceptions of the nature of the programs. To the student population, vocational programs resembled the usual stereotype “school.” The solution to this problem was not simple. In order to achieve a real life simulation of work, teachers would need to grant additional freedom to students, which presents a calculated risk to the student and the instructor.  相似文献   
918.
The Prevention of Significant Deterioration (PSD) doctrine has been one of the most hotly contested aspects of U. S. air pollution law. In its present form, it exerts powerful influence on land-use planning and plant siting. It has worked in the past and will presumably work in the future to increase the amount of air pollution to which the average American is regularly exposed. It has serious technical flaws. Some alternative PSD policies which remedy these flaws are proposed.  相似文献   
919.
On June 5 and 6 of 1980, two parallel plume oxidation studies were carried out in the vicinity of the Tennessee Valley Authority's Colbert Steam Plant. One study was performed in a smog chamber into which stack gases were injected and mixed with ambient air. The other study included direct airborne sampling of the power plant plume. Atmospheric oxidation rates for the conversion of SO2 to SO4 2- and the removal rates of NO x (which is presumably the rate of NO3 - formation) were estimated for both studies. The SO2 to SO4 2- rate coefficients were found to be 0.022 ± 0.009 h-1 for both chamber experiments and the first airborne sampling day. For the second day, a rate constant of 0.041 ± 0.052 h-1 was estimated from the aircraft data. The large deviation in this value is explained by the fact that the plume from the power plant combined and reacted with the urban plume from the city of Florence, AL. The formation of a very large "O3 bulge" on this day is also attributed to the mixed plumes. The first order rate coefficients for NO x removal were estimated to be 0.27 ± 0.14 h-1 for both chamber experiments and the first airborne sampling day. A NO x removal rate could not be determined for the second airborne sampling day.  相似文献   
920.
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