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441.
442.
443.
S. F. Liang C. V. Sternling T. R. Galloway 《Journal of the Air & Waste Management Association (1995)》2013,63(7):605-607
This paper presents a simplified analysis to determine the variables that affect the empirical correlation factor used in the lead peroxide method. The rate of sulfation has been determined from two different models. In the first model, the mass transfer rate is calculated from the gas phase resistance alone whereas in the second model, the diffusion resistance in the gel phase is assumed to be the rate limiting step. Although the gas phase and the gel phase resistances may be both important in the actual case, it has been found that the correlation factor based on the first model is adequate to describe general experimental observations. Reasonable agreement has been obtained between the measured and the calculated va|ue of the correlation factor. 相似文献
444.
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
445.
Bruce Lighthart Victor E. Hiatt August T. Rossano Jr 《Journal of the Air & Waste Management Association (1995)》2013,63(10):639-642
Aerosols of Serratia marcescens ATCC 274 were suspended in a 709L rotating drum at 20 ± 1 °C and high to mid-range relative humidities. At specified times after bacterial aerosolization, sulfur dioxide was added to concentrations of 2.5, or 5 mg/m3. Viable cell decay rate constants, in control aerosols without added sulfur dioxide, increased rapidly from near 100% to 60% RH in the first hour (termed: young aerosol) of suspension, and from a minimum rate constant at 80% in the succeeding four hours (termed: old aerosol).Upon addition of sulfur dioxide to a cloud of S. marcescens, generally, viable cell decay rate constants increased further. One exception was at 80% relative humidity where maximum resistance to SO2 accelerated death was observed for old aerosols. Cells in young aerosols were particularly sensitive to SO2 addition at mid-range humidities, while in older aerosols the cells were insensitive to up to 5 mg SO2/m3 introduced at high RH; but were up to 10 times more sensitive than cells in young aerosols to a given increase (from 2.5 to 5 mg/m3) in SO2 concentration at mid-range humidities. 相似文献
446.
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
447.
M. E. Smith T. T. Frankenberg 《Journal of the Air & Waste Management Association (1995)》2013,63(6):595-601
A study of the “before” and “after” ground-level S02 concentrations near the Muskingum River Plant of the American Electric Power System shows that the conversion from low to high stacks has accomplished marked reductions in ambient concentrations. These reductions are in reasonable agreement with theoretical calculations and are most apparent within 5 km of the source. EPA Standards are now being met in this area despite the presence of the 1440 MW power plant burning 5% sulfur fuel with no treatment of the stack gas. 相似文献
448.
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
449.
Mark L. Kramer Maynard E. Smith Michael J. Butler David E. Seymour Theodore T. Frankenberg 《Journal of the Air & Waste Management Association (1995)》2013,63(6):582-584
Measurements of natural draft cooling tower plume behavior, as well as meteorological variables, were obtained from aircraft flights near major power plants of the American Electric Power System. Persistence of the visible plume to great distances depends essentially on ambient humidity. Atmospheric stability at plume elevation was also important. Cooling tower-induced fog at ground-level was never observed in any of the tests, and aerodynamic downwash of the visible plume was absent also. The cooling towers did cause modification of natural clouds and they occasionally shadowed some local areas from the sun. Merging of the stack and cooling tower plumes was a common occurrence. 相似文献
450.
Roger J. Cheng Volker A. Mohnen Thomas T. Shen Michael Current John B. Hudson 《Journal of the Air & Waste Management Association (1995)》2013,63(8):787-790
The emphasis on participate control from industrial processes has been shifted recently towards fine particulates, having diameters less than 3 microns. There exists an urgent need for more scientific information of fine particle characterization.1,2 Coal and oil fired power plants are among the largest anthropogenic point sources of particulate matter.3 Limited knowledge is available on particle size distribution and trace metal composition in power plant emissions.4-7 The morphological properties of particle emissions have been largely neglected. In this report we present some information on particle characteristics for an oil-fired and coal-fired power plant. 相似文献