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951.
H. C. Wohlers M. Feldstein 《Journal of the Air & Waste Management Association (1995)》2013,63(5):226-229
The problem of an investigation of the need for a regulation on organic compound emissions in the San Francisco Bay Area can be divided into two major areas: 1. Is there a need for a regulation on organic compound emissions? What is the extent of photochemical smog effects? How much control is necessary to achieve the desired effects? 2. (2) If the need exists for an organic compound regulation, can a performance type regulation be written for all types of organic compound emissions? Must the regulation be directed toward specific industries or types of emissions? Can the regulation be adequately enforced—both practically and legally? This paper will describe the studies undertaken by the District Staff to answer the first set of questions. Work covering the second group of questions is now under investigation. 相似文献
952.
H. P. Sanderson R. Thomas Morris Katz 《Journal of the Air & Waste Management Association (1995)》2013,63(6):328-330
Field experience with the lead acetate impregnated paper tape sampler has indicated that large errors may arise in this method due to fading of the color of the precipitated lead sulfide spots. This fading is due to the action of light, sulfur dioxide, ozone, on other substances capable of oxidizing lead sulfide. The moisture content or relative humidity of the air sample must be maintained at an appropriate level to ensure reaction with the impregnated paper tape. The effects of the factors have been investigated in laboratory experiments with known concentrations of H2S. A number of antioxidants were studied in relation to the stability of the resultant spots to light and oxidation Orthophenyl phenol was found to be the most effective antioxidant for this purpose. A number of necessary precautions to be employed in the use of the lead acetate method are recommended and the limitations are discussed. 相似文献
953.
A. H. Phelps Jr. 《Journal of the Air & Waste Management Association (1995)》2013,63(8):505-507
Informative Report No. 8 on soap and detergent manufacture is one of a series of survey reports prepared by APCA’s Tl-2 Committee on air pollution problems and control methods encountered in the chemical industry today. 相似文献
954.
955.
C. M. Peterson H. J. Paulus G. H. Foley 《Journal of the Air & Waste Management Association (1995)》2013,63(10):795-801
Instruments capable of measuring in situ numbers of particles within specific size ranges covering a particle-diameter spectrum of approximately 0.001 – 10 microns have been employed to continuously monitor the concentration and size-distribution of atmospheric aerosols. The monitoring site was a television tower located on the boundary between Minneapolis and St. Paul, Minnesota. Air samples were drawn from 70, 170, and 500 feet above ground level and analyzed with optical, electrical, and condensation particle counters to obtain a number-size distribution within the 0.001 – 10 micron size range. In addition to the measurement of particle number and size, several micrometeorological parameters were simultaneously monitored. Particle number-size distributions which were measured during periods of temperature inversion are reported 相似文献
956.
B. A. Brodovicz Jr. V. H. Sussman G. B. Murdock 《Journal of the Air & Waste Management Association (1995)》2013,63(7):484-489
The Pennsylvania Air Pollution Commission has developed a regulatory program based upon the control of local air pollution problems and reduction of pollutant levels in air basins. The geographical boundaries of 10 air basins have been established. The Commission’s air basin regulations will provide for the reduction of over-all pollutant levels and for emergency procedures in the event of adverse meteorological conditions. The paper discusses the format and objectives of the program. In order to effectively enforce the air basin regulations and maintain the necessary surveillance of the state’s air quality, a "computerized real time on-line integrated air monitoring-data handling system" has been designed. The system will incorporate a network to constantly monitor the air in each air basin.The primary objectives of the system are: 1. Constant surveillance of air pollution in the air basins. 2. Provide information on air pollution potential alerts. 3. Aid in further development of air quality criteria and regulations. The air monitoring network is estimated to include approximately 25 remote stations. Each remote will contain air pollution and meteorological sampling equipment and hardware to telemeter to a central station. The data will be transmitted over leased telephone lines. The central station in Harrisburg will contain the necessary hardware to receive and process data, calculate and display results and permit supervisory control of the network. Output options will include immediate display of edited data, command and alarm information, and presentation of statistical results. Although the air monitoring system is one of the principle ingredients of the program, the air basin concept encompasses other component systems designed to knit together the entire air pollution control program in Pennsylvania. 相似文献
957.
H. H. Meredith JR 《Journal of the Air & Waste Management Association (1995)》2013,63(11):719-723
An American Petroleum Institute study of desulfurization of Caribbean fuel oil was completed in February 1967. The report is unique in that proprietary information was made available to the contractor, the Bechtel Corp., by task force members and licensors of desulfurization processes. Thus confidential information never before available to a single organization was used to develop feasibility and incremental costs of various processes for desulfurization. The report provides needed guideposts for decision-making by governmental units as well as by industry. Incremental costs are presented for intermediate levels of desulfurization from the normal level for Caribbean heavy fuel oil of 2.6% down to 0.5%, as well as the sensitivity of costs to sulfur credits and to rate of recovery of invested capital. Degree of justifiable confidence in the various data is discussed. Effects of desulfurization on other characterisics of the fuel oil are also discussed. 相似文献
958.
959.
960.
Héctor G. Riveros Javier Tejeda Luis Ortiz Adriana Julián-Sánchez Héctor Riveros-Rosas 《Journal of the Air & Waste Management Association (1995)》2013,63(12):973-984
Abstract In Mexico City, the use and composition of fuels determine that carbon monoxide (CO) comes mostly from mobile sources, and sulfur dioxide (SO2) from fixed and mobile sources. By simultaneously measuring hydrocarbons (HC), CO, and SO2 in the atmosphere of Mexico City, the relative amounts coming from different sources can be estimated. Assuming that some HC are emitted proportionally to CO emissions, we can establish that [HC]1= m1? [CO], where the proportionality constant ml corresponds to the ratio of emissions factor for HC and CO in mobile sources. Similarly for fuels containing sulfur, it can be assumed that [HC]2 = m2 ? [SO2]. In this way, the total HC are [HC]total=[HC]0+ ml ? [CO]+ m2 ? [SO2], where [HC]0 corresponds mainly to other sources like solvent evaporation, gas consumption, and natural emissions. In this way, it can be estimated that in Mexico City 75% of average HC comes from mobile sources, 5% from sulfur-related sources, and 19% from natural sources and solvent evaporation. Compared with the HC/CO ratio measured in the exhaust pipe of vehicles, we estimated that 70% of HC emitted from mobile sources are evaporative losses, and only 30% come through the exhaust system. 相似文献