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641.
William W. Moyer Fred P. Osman 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1155-1157
Portable air quality monitoring systems may be required to supplement fixed installations or to provide for quick response to a transient situation, possibly at a remote location. A microprocessor-based monitoring unit has been developed for use with existing sensors. The unit is portable and its operational sequence can be programmed to adapt it to any unique requirements existing at the deployment site. Selectable on-site calculations are performed on raw data, and a hard copy or tape record of results can be produced. 相似文献
642.
J. Stuart Fordyce Dean W. Sheibley 《Journal of the Air & Waste Management Association (1995)》2013,63(7):721-724
Samples of ASTM type A jet fuel were analyzed for trace element content by instrumental neutron activation techniques. Forty-nine elements were sought. Only ten, aluminum, gold, indium, lanthanum, titanium, vanadium, barium, dysprosium, tellurium, and uranium, were observed at levels above the detection limits encountered; of these only aluminum, titanium, and barium were present at concentrations greater than 0.1 ppm. Estimates of exhaust gas. concentrations are made, and the ambient contribution at or near airports is calculated by using the Los Angeles International Airport dispersion model. It is shown that the ambient contribution is about an order of magnitude below typical urban levels for virtually all elements sought. 相似文献
643.
Michael J. Massey Robert W. Dunlap 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1019-1027
Two processes are currently being employed in North America for the desulfurization of coke oven gas, the Vacuum Carbonate System, and the Stretford System. A third, the Sulfi-ban Process, which was recently announced, now has several plants scheduled for construction. Overall operating requirements for each of these processes are considered in detail. Emphasis is placed on an identification of power and steam requirements, the types and amounts of solid and/or liquid waste streams produced together with methods for their treatment, and the net desulfurization efficiencies achieved by each process. Detailed estimates of capital and operating costs for desulfurization are considered, and equipment needs for environmental control requirements are discussed. 相似文献
644.
J. G. Munson Jr. R.E. Lewis G.T. Weber W.E. Brayton 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1059-1062
At the Clairton Coke Works of the United States Steel Corporation (the world’s largest coke plant), with coal charges of about 30,000 net tons per day, a system designated as “stage charging” has been developed for charging coal into the coke oven chamber without emissions to the atmosphere. The principles of the system are based on controlled sequential flow of the coal from the charging hoppers, during which the oven chamber is maintained under a very slight negative pressure condition by use of steam aspiration in the offtakes for on-the-main charging. The techniques are basic but require knowledge of the coal characteristics, adequate and properly maintained aspirating systems, including clean offtake piping, control of coal volume in the individual hoppers, and last, and probably most important, adherence by the operating crew to specific charging and leveling practices. 相似文献
645.
Performance and Cost Comparisons between Fabric Filters and Alternate Participate Control Techniques
J.D. McKenna J. C. Mycock W.O. Lipscomb 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1144-1148
A study was conducted to evaluate performance and cost comparisons of fabric filters and alternate fine particulate control techniques. In relating the removal of fine particulate to costs, due to the lack of fractional efficiency data, it was found necessary to treat a specific application in order to make the study manageable. The case chosen is that of the coal fired industrial boiler since Enviro-Systems has a pilot program in this application area. 相似文献
646.
Robert W. Fri 《Journal of the Air & Waste Management Association (1995)》2013,63(9):912-914
As many of you know, I previously served as Deputy Administrator of the Environmental Protection Agency at a time when the problem of air pollution control was reaching a peak of public awareness. The work of the Air Pollution Control Association in investigating facts and accelerating the development of solutions earned my high respect then and my continued admiration now. 相似文献
647.
William M. Porch Hugh W. Ellsaesser 《Journal of the Air & Waste Management Association (1995)》2013,63(2):134-137
Noontime visibilities in downtown Los Angeles, averaged over the smog season of June through November, show two cycles of general deterioration and improvement. The improvement since 1962 is confirmed by available high volume filter data and conditions in 1974/75 are at least as good as at anytime since observations were begun in 1933. The decrease in frequency of “rule 57” days suggests that the improvement of the last decade and perhaps the cyclic variation of the past 40 years has been primarily of meteorological origin. 相似文献
648.
Hans-Jürgen jáger Hartmut Klein 《Journal of the Air & Waste Management Association (1995)》2013,63(5):464-466
Biochemical and physiological experiments were conducted on pea plants (Pisum sativum) continuously exposed in growth chambers to SO2 gas for 18 days. S02 gas concentrations were 0.1, 0.15, and 0.25 ppm. In plants exposed to 0.1 and 0.15 ppm it was clearly demonstrated that there was a greater accumulation of inorganic sulfur, a reduced buffer capacity of the cells relative to H-ions, and a stimulation of glutamate dehydrogenase activity. The only macroscopic symptom seen was slight chlorosis of the older leaves. There was only a slight decrease in fresh and dry weights of these plants compared to the control plants whereas in the group of plants exposed to 0.25 ppm SO2 foliage necrosis was considerable. In addition, there was a marked reduction in the fresh and dry weights of the latter plants. However, the relationship among accumulated inorganic sulfur, reduced buffer capacity, and increased glutamate dehydrogenase activity as seen for the lower S02 concentrations was close. Accordingly, if might be possible to use these three parameters to diagnose S02 injury before any significant symptoms appear. In the case of severe SO2 injury there was a marked increase in glutamine and ammonia concentrations suggesting that these factors in addition to the above could be used in diagnosing severe SO2 injury. There was no significant difference between plants treated with 0.1 or 0.15 ppm SO2 and control plants in the contents of K, Ca, P, and N fractions. Therefore, these factors would not be useful in the early detection of SO2 injury. 相似文献
649.
George W. Haering 《Journal of the Air & Waste Management Association (1995)》2013,63(11):1120-1121
There are doubts concerning the sources of the pollutant ozone in an urban location. Current control regulations,1 for example, are based on local sources. Many studies suggest that plumes of pollutants released by upwind areas are the cause. For example, New York City has been associated with high O3 in New England,2 Chicago with O3 in Milwaukee,3 and St. Louis with O3 in rural Illinois.4 Others5,6 have suggested the problem must be treated on a synoptic scale. In an effort to understand the problem at Indianapolis better, a series of experiments involving aircraft flights were conducted in the Indianapolis area and their results are herein reported. Specifically, a cross country flight of over 100 mi both to the northeast and southwest of Indianapolis, a vertical spiral to 28,000 ft, low level data associated with takeoff and landing of the aircraft, and ground data at four sites, are available for the afternoon of June 9,1976. 相似文献
650.
Charles Brunot Thomas W. Stanley 《Journal of the Air & Waste Management Association (1995)》2013,63(7):717-719
Quality Assurance has been defined in many different ways to express concern for the “quality” of the output of some operation or function. For the purpose of this presentation, quality assurance is defined as the sum of those activities within an environmental monitoring or measurement program which are primarily for the purpose of documenting the precision, accuracy, representativeness, and completeness of the data that are produced. Further, we view quality assurance as a management tool which encompasses both administrative and technical functions which generally fall into three categories: (1) Prevention which includes those activities carried out prior to the proper placement and operation of the measurement system; (2) Evaluation which includes the continuous overview and checks on the performance of the systems and operators; and (3) Correction which includes changes made to improve or stabilize the capability and performance of the system. 相似文献