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941.
H. A Belyea W. J Holland 《Journal of the Air & Waste Management Association (1995)》2013,63(5):320-323
Field tests were conducted on 82 fuel-burning installations ranging from 50 to 500 hp, fired with residual fuel oils. A flame pyrometer was used to measure peak flame temperatures. Coarse particulates were measured by impingement on adhesive paper strips inserted at right angles to the gas flow and fine particulates by filtration of the gas sample through filter paper. Both were evaluated using a standard Bacharach Scale. The tests clearly established that both coarse and fine particulate matter invariably occurred with low flame temperatures but decreased appreciably when peak flame temperatures reached approximately 2650°F; Minimum values were observed at temperatures somewhere between 2750 and 2850°F. This research was conducted as a result of the problem of acid smut and carbonaceous (ceno-sphere) fallout which appears to have increased with the advent of modern high-efficiency low-temperature heating installations and taller, cooler operating chimneys; sudden deluges of particles from the chimney serving large oil-burning plants soil clothing, pit car finishes, and damage nylon stockings and other materials. 相似文献
942.
M. Griggs 《Journal of the Air & Waste Management Association (1995)》2013,63(5):356-358
In recent years there has been considerable use of optical observations to determine the aerosol mass loading of the atmosphere. Nephelometer measurements of the scattering coefficient have been used for the local volume mass loading, and the turbidity of the atmosphere determined by the Volz sun photometer has been related to the vertical mass loading. This paper analyses various approaches to measuring the mass loading, and presents improved relationships between the optical observations and the aerosol mass loading. 相似文献
943.
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
944.
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
945.
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
946.
947.
948.
949.
John M. Pierrard 《Journal of the Air & Waste Management Association (1995)》2013,63(9):632-637
The role of particulate matter and oxides of sulfur in degradation of the atmospheric environment is discussed. The Federal Air Quality Criteria for these pollutants are analyzed for their conformance with the requirement of the Clean Air Act of 1967 that they reflect the latest scientific knowledge pertinent to the indication of their effects on health and welfare. Visibility reduction by suspended particulate matter is treated and the bases for the criteria issued in the documents “Air Quality Criteria for Particulate Matter” and “Air Quality Criteria for Sulfur Oxides” are examined. The reactions between particulate matter and gaseous pollutants are discussed, along with the Impact of particulate matter on modifications of weather processes. Local effects, such as precipitation, are considered. The relationship between pollution by particulate matter and cloud formation is discussed, as are persistence of fog and the observation that certain sources of particulate pollution are also sources of ice nuclei. 相似文献
950.
M. Boulerice W. Brabant 《Journal of the Air & Waste Management Association (1995)》2013,63(6):432-434
Since 1966, the Division of Laboratories of the Department of Health of the City of Montreal is carrying on measurements of gaseous pollutants. In order to efficiently use the technical staff that our administrators wanted to devote to the fight against air pollution, a new lead dioxide support for the determination of sulfur dioxide has been devised. The preparation of candies according to the standard method requires much time and skill from the operator, whereas the technique that is proposed is rapid, easy, and provides plates of a high degree of uniformity. A technician with little experience can coat a great number of plates per day with no difficulty. N. A. Huey working at the National Center for Air Pollution Control in Cincinnati published in the September 1968 issue of this Journal a new technique which consists of coating the inside of a plastic Petri dish with a PbO2 paste. His method also has the above mentioned advantages. The plates that are suggested allow a simplification of the preliminary work for several types of analyses such as gra-vimetry,1 colorimetry,3 turbidimetry,4,5 titrimetry,6 and nephelemetry.8 相似文献