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591.
J. L. Jones E. A. Sckuck R. W. Eldridge N. Endow F. W. Cranz 《Journal of the Air & Waste Management Association (1995)》2013,63(2):73-77
While snowflakes fell and Christmas carols heralded the imminent holiday, over 3000 delegates to the Third National Conference on Air Pollution were told to “Control Now for Clean Air.” They were told this in many ways by many people—by the Vice President of the United States; by the Secretary of the Department of Health, Education, and Welfare who summoned the Conference; and by senators, congressmen, governors, and mayors. Then eight panel sessions convened to discuss and to determine how to control now for clean air. Speakers from every section of American life addressed themselves to this subject; when they were finished, the eight session chairmen summarized what had been said, what had been, learned. These summaries appear on the following pages. 相似文献
592.
N. E. Bowne 《Journal of the Air & Waste Management Association (1995)》2013,63(8):570-574
A different approach to mathematically modeling large-scale atmospheric processes is presented. Whereas past approaches have been to develop a model based on an accumulation of information from a specific geographical area, resulting in a model applicable to that area only, we have developed a general mathematical model applicable to any geographical area. The model’s applicability is controlled by specifying the input information describing the meteorological situation and pollution source configuration. A rectangular array of grid points is used to specify both the wind field, by using stream functions, and the average source strength of some pollutant for the area represented by the grid. The diffusion problem is divided into two areas: transport by the mean wind field, and dispersion based on travel time and distance as described by empirical equations. Trajectories of pollutants are traced backwards from the points of interest in the course of the calculations and the contributions of all sources that affect the points of interest are accumulated. The model requires an array of source strength information. An inventory of pollution sources in the State of Connecticut was compiled and maps of source strengths were prepared for five pollutants on a 5000-ft grid-square array. Maps of sulfur dioxide and carbon monoxide source strengths are presented with the resulting concentration distribution for “typical” meteorological conditions. The model permits the changing of meteorological or source values at predetermined intervals so that diurnal changes are incorporated in the calculations. The model has not been verified, but the values of pollution concentration are the right order of magnitude and the resulting patterns are as expected. 相似文献
593.
John C. Elston Richard G. Kolb Irmin . Kamm John N. Pattison 《Journal of the Air & Waste Management Association (1995)》2013,63(10):767-772
This paper reports on the research program undertaken by the State of New Jersey to determine those tests and instruments which can be used by authorized state agencies for the enforcement of diesel smoke emissions. The state agencies under consideration for the enforcement of diesel smoke emissions are the following: (1) The Division of Motor Vehicles, in its system of state owned inspection stations, will be able to inspect all diesel-powered trucks, and tractors which are registered in New Jersey. (2) The Public Utilities Commission will be able to inspect at their home garages all buses registered in the State. (3) The New Jersey State Police will be able to inspect diesel-powered vehicles on the road. It was decided that the maximum inspection time for each vehicle was not to exceed one minute. On the basis of the one minute per vehicle requirement, eight different tests were evaluated to determine which ones correlated well with normal vehicle operation. These tests included acceleration of a fixed external inertia, free acceleration of only the moving parts of the engine, three ramp tests, a test in which a heavy vehicle was towed, and a driving test in which the vehicle being tested was actually accelerated. The results of tests demonstrated that the modified free acceleration method correlates reasonably well with a loaded steady state cycle, distinguishes the high emitters and is simple to perform. Consequently, the free acceleration test method is recommended for use in inspection stations and on the road. Finally, nearly two hundred vehicles have been tested by this procedure to determine present and potential levels of diesel smoke emissions. Another phase of the program consisted of the determination of smoke measuring techniques and instrumentation. The use and design of smokemeters were extensively investigated, as well as the use of the visual and photographic techniques. Of the various smokemeters tested for this application, several measured smoke satisfactorily in the laboratory, but none were found adequate for field use; they either lacked portability or were unstable due to the deposition of soot on the optics. At the time of writing, specifications for the necessary smokemeter have been drafted and published for bid to interested manufacturers. 相似文献
594.
J. B. Maynard W. N. Sanders 《Journal of the Air & Waste Management Association (1995)》2013,63(7):505-510
The quantitative data obtained with a capillary GLC method, which is used to determine the individual C3-C12 hydrocarbons in full-range motor gasolines, have been employed in a computer program to calculate the hydrocarbon composition of the vapor in equilibrium with a gasoline at 100°F, as well as the equilibrium vapor-pressure of the gasoline at that temperature. The method used for computation is similar to that previously described by McEwen, assuming the gasoline to behave as an ideal liquid. Also calculated is the potential atmospheric reactivity of this equilibrium vapor relative to that from other gasolines when specific reactivity weighting factors for the individual hydrocarbons are employed. Calculated total vapor-pressure data agree well with experimental Reid vapor-pressure data obtained for typical premium-grade gasolines. Definite differences were observed in the relative potential atmospheric reactivities calculated at 100°F for the equilibrium vapors from the test gasolines. 相似文献
595.
J.N. Driscoll A.W. Berger J.H. Becker J.T. Funkhouser J.R. Valentine 《Journal of the Air & Waste Management Association (1995)》2013,63(2):119-122
The nitrate ion selective electrode was investigated as an alternative approach to the present colorimetric determination of nitrate resulting from oxidative absorption of nitrogen oxides from combustion effluents. The electrode offers advantages of speed and relatively simple experimental procedure. Replicate measurements of 10?4–10?2M nitric acid solutions using bracketing standards show that the electrode approach is capable of good precision (coefficient of variation = ±4%). Comparison of a method utilizing the nitrate electrode with the more laborious phenol disulfonic acid method for the measurement of nitrogen oxides in both oil and gas fired combustion effluents showed agreement within 4% of the mean even in the presence of high levels of SO2. The correlation coefficient found for PDS vs nitrate electrode is 0.987. 相似文献
596.
N.C.G. Freeman T. Wainman P.J. Lioy A.H. Stern S.I. Shupack 《Journal of the Air & Waste Management Association (1995)》2013,63(8):604-605
Honorary Memberships are conferred by the Air Pollution Control Association on persons of widely recognized eminence in some part of the field of air pollution control or who have rendered especially meritorious service to the Association. Honorary Memberships were awarded this year to Dr. Leonard Greenburg and Mr. Milton Reizenstein, both past presidents of APCA. 相似文献
597.
V.N. Finelii M. Karaffa M. Malanchuk R.M. Danner L. McMillan S.D. Lee 《Journal of the Air & Waste Management Association (1995)》2013,63(3):231-233
The introduction of oxidizing catalytic converters in the exhaust system of automobiles has been found to be effective in reducing carbon monoxide, total hydrocarbons, and some other components of tailpipe emissions. The utilization of these converters, however, has also caused further oxidation of sulfur compounds producing an increased amount of sulfur trioxide (SO3) which yields sulfuric acid and sulfates.1 Studies on the biological effects of these sulfur compounds are in progress in our laboratory and preliminary findings are reported separately. This paper compares the biological effects of exposure to whole emissions from engines with and without converter and exposure to carbon monoxide alone. 相似文献
598.
James N. Galloway Ellis B. Cowling 《Journal of the Air & Waste Management Association (1995)》2013,63(3):229-235
Precipitation is one of the most important factors determining the nature and productivity of terrestrial and aquatic ecosystems. Detailed historical and contemporary records are available indicating the amount of water deposited at thousands of locations throughout the world. Comparatively, however, knowledge of the changing chemistry of precipitation has developed only recently and is still very fragmentary. Our present ignorance of the total impact of changes in precipitation quality on the productivity and stability of ecosystems is especially profound. This paper has a fourfold purpose: (1) to describe the myriad of trace chemical constituents transferred from the atmosphere into the biosphere of the earth; (2) to define the range of beneficial and injurious ecological effects of perturbations in atmospheric deposition; (3) to explain the concepts of sensitive areas, life stages, and life forms; and (4) to describe briefly plans for a National Deposition Network and associated research on the terrestrial and aquatic ecosystems of the United States. 相似文献
599.
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