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711.
Charles D. Yaffe William F. Johnson 《Journal of the Air & Waste Management Association (1995)》2013,63(5):316-318
Ambient air standards, emission standards, and program activities are considered in a search for appropriate indices for measuring program progress and effectiveness. The authors suggest that such indices can best be based on data related to weight of emissions. Several methods for expression accomplishment are presented for consideration. 相似文献
712.
Roy O. McCaldin Louis W. Johnson 《Journal of the Air & Waste Management Association (1995)》2013,63(6):405-409
An instrumented single engine aircraft is being used to characterize plumes from large emission sources. By cross sectioning these plumes at a number of points we hope to describe the character and concentration of pollution as it ages and travels downwind under known meteorological conditions. This paper reports experimental work thus far completed on aerosol measurement. Flights have been made through plumes from a large coal-fired power station, forest fires, and a gravel plant. Particle counts in various size classifications were made with a Bausch and Lomb 40–1 Dust Counter which was carried in the aircraft. Selected meteorological parameters were recorded. Results show the aerosol concentrations in various size classifications that are found at successive distances downwind from these sources for distances up to 32 miles. Background aerosol concentrations are also reported, and variations in these can be noted with respect to time, location and altitude. 相似文献
713.
H. C. Johnson H. A. James 《Journal of the Air & Waste Management Association (1995)》2013,63(8):530-533
Intermingled land usage in the 3900 square mile Bay Area Air Pollution Control District presented special problems in curtailing open burning. Regulation 1, adopted in 1957, prohibited most types of open burning, with exceptions for public safety, instruction in fire fighting, flood control, agricultural burning and one- and two-family dwellings.Variances for open burning could be granted by the District’s Hearing Board.The need was established for utilizing the services of professional meteorologists for planning and carrying out open burns.Their proposals to limit adverse effects were : (1) Select a day of no inversion, with wind direction to carry pollutants away from local targets; and, (2) a day of low velocity at ground level, high velocity at high altitudes. Predicted meteorological conditions have been met for up to eight hours in a high percentage of cases. Experience has proven the need for proper stacking and drying of the wood waste to assure high temperature burning, and completion of the burn as scheduled. Even though the cost of hauling to landfills may be substantially more than the cost of burning under a variance, hauling is often selected because of the time required for stacking, drying, and waiting for designated meteorological conditions. Substantial progress has been made in curtailing agricultural burning. Burning of greenhouse waste has been stopped.on emissions from orchard heaters has resulted in replacement with new smokeless heaters.Orchard brush can be burned only on “burn days” designated in the winter when the inversion is predicted to be above 2500 ft. Stubble burning has continued due to the lack of a feasible alternative. Range brush burning also continues, mostly in remote areas of high elevation. Lumbering slash is burned at the insistence of forestry officials. The above burning could be limited to designated burn days, as is successfully being applied to orchard brush. Research on alternatives to agricultural burning is being spearheaded by the University of California, and its agricultural extension service. Each project usually requires several years to carry out and evaluate. Closer cooperation by all involved in agriculture and air pollution control is necessary to develop feasible alternatives to open burning. 相似文献
714.
K. L. Johnson 《Journal of the Air & Waste Management Association (1995)》2013,63(6):399-401
In 1964, as part of the Northeastern Illinois Metropolitan Planning Commission's Air Resource Management Study, an examination was made of citizen complaints of air pollution registered with air pollution control agencies representing the City of Chicago, outlying Cook County, and the State of Illinois. The complaint files of the City of Chicago were found to contain the addresses of some 9500 air pollution sources specified by complainants in complaints covering the time period from approximately 1954 to 1964. A statistical sample of these sources showed more than 70% to be of a nonindustrial nature, with domestic fuel burning or incineration by neighbors most often specified. There were 1119 industrial process source snamed in the Chicago files; 588 nonmanufacturing and 531 manufacturing. Fabricated metal industries, primary metal industries, chemical manufacturers, and food processing plants were cited more often than other industrial categories. Complaint sources named in complaints filed by citizens with the State of Illinois, and with Cook County, differed with those of Chicago in that industrial sources were specified more often than nonindustrial ones. The reason for this is believed to lie in the reduced residential densities and the relatively great use of pollution-free fuels in the metropolitan area outside of the City of Chicago. 相似文献
715.
H. C. Lord D. W. Egan F. L. Johnson L. D. Mc Intosh 《Journal of the Air & Waste Management Association (1995)》2013,63(2):136-139
A versatile but simple, reliable, rugged, and compact vehicle exhaust monitoring system has been developed, allowing detection of carbon monoxide (CO), carbon dioxide (COo), high and low hydrocarbons (HHC and LHC), and nitric oxide (NO). The analysis is performed by dispersive absorption spectroscopy with instrumentation designed and fabricated for this demanding industrial environment. The operation of the instrumentation is described here, as well as results for both diesel and piston engine emission testing. This equipment has been used for California 7 mode-7 cycle hot start and cold start tests, the California heavy-duty engine test cycles, EPA CVS tests reading bag samples and also continuous dilute, and finally it has been used for idle checks. Testing has been performed on production automobiles, as well as those equipped with thermal reactors or catalytic mufflers, and also both heavy-duty gasoline and diesel. engines. The instrumentation has shown very good correlation with other established techniques, and because of its sensitivity, selectivity, ruggedness, and simplicity, has been shown to be suitable for vehicle emission analysis. Applications include assembly-line testing, engine testing, certification testing, quality audit testing, emission lab testing, and research. 相似文献
716.
717.
Hanwant B. Singh William Viezee Warren B. Johnson Francis L. Ludwig 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1009-1017
A background of ozone (O3), principally of stratospheric origin, is present in the lower free troposphere. Typical mean O3 levels of 50 ppb, 40 ppb, and 30 ppb are encountered here in spring, summer, and fall, respectively. Maximum hourly O3 concentrations which are twice these mean values can be expected. Ozone from the free troposphere is routinely brought down to ground level under turbulent atmospheric conditions. Deep and rapid Intrusions of stratospheric air into the lower troposphere are associated with low-pressure troughs and occur regularly. In the mid troposphere, O3 levels as high as 300 ppb are found within these intrusions. Observational data showing these intrusions, containing high O3 concentrations, to directly reach ground level are currently lacking. Over the United States, an intrusion was present aloft on 8 9% of the days in 1978. The frequency, however, is somewhat reduced in summer and a northward movement is evident. During 1978, no intrusion occurred south of 30°N between June and August and none south of 40 °N in August. The hypothesis that low levels of stratospheric O3 produce disproportionately large amounts of O3 in the polluted atmosphere cannot be supported from currently known chemistry but should be studied further. The experimental technique involving a 7Be/O3 ratio to estimate the daily stratospheric component of ground level O3 is unverified and considered to be inadequate for air quality applications. Estimates resulting from such a technique are considered uncertain by a factor of more than three. Specially designed aircraft studies provide the best means to determine quantitatively the impact of stratospheric O3 on ground level air quality. 相似文献
718.
James J. Franz Vice Chairman Robert Bethea Milton Feldstein Howard Hesketh Ralph Johnson Robert Kenson 《Journal of the Air & Waste Management Association (1995)》2013,63(2):173-175
ABSTRACT Solid phase microextraction (SPME) presents many advantages over conventional analytical methods by combining sampling, preconcentration, and direct transfer of the analytes into a standard gas chromatograph (GC). Since its commercial introduction in the early 1990s, SPME has been successfully applied to the sampling and analysis of environmental samples. This paper presents an overview of the current methods for air sampling and analysis with SPME using both grab and time-weighted average (TWA) modes. Methods include total volatile organic compounds (TVOCs), formaldehyde, and several target volatile organic compounds (VOCs). Field sampling data obtained with these methods in indoor air were validated with conventional methods based on sorbent tubes. The advantages and challenges associated with SPME for air sampling are also discussed. SPME is accurate, fast, sensitive, versatile, and cost-efficient, and could serve as a powerful alternative to conventional methods used by the research, industrial, regulatory, and academic communities. 相似文献
719.
C. E. Tatsch W. M. Yeager G. L. Johnson 《Journal of the Air & Waste Management Association (1995)》2013,63(6):655-660
An interactive computer resource for analyzing, evaluating, and archiving particle size distributions as determined by cascade impactors for environmental measurement is decribed. The Particle Data Reduction (PADRE) computer program assists users in obtaining high quality size-mass distribution data for archival in the Fine Particle Emissions Information System (FPEIS). PADRE users interactively store, edit, reduce, and analyze observed impactor data from anywhere in the continential United States. Extensive data quality checks and computer- prompted, user-directed program operations assist users in obtaining meaningful information within minutes of entering impactor data. Design goals, program operation, sample sessions and plans for future system development are discussed. 相似文献
720.
R. M. Adams J. D. Glyer S. L. Johnson B. A. McCarl 《Journal of the Air & Waste Management Association (1995)》2013,63(7):960-968
The potential adverse effects of environmental change on agriculture have motivated considerable public research on this topic. Acid deposition, gaseous air pollutants, stratosphere ozone depletion and "green house" phenomena, individually and in combination, have been or are being evaluated in terms of effects on agricultural productivity. Assessments of the economic consequences of such effects have also been performed as input into the regulatory process. As with any applied bioeconomic analysis, the credibility of these economic assessments is dependent on the quality of the natural science and other data on the pollutant In question. The ability of economists to assess the agricultural effects of one important pollutant, tropospheric ozone, has been Improved by the recently completed National Crop Loss Assessment Network (NCLAN). The structure, protocols and initial plant science findings of this U.S. Environmental Protection Agency program have been presented in this journal (see, for example, Heck et al).1-2 In a related article,3 we reported the economic consequences of those preliminary ozone crop yield effects. Summary plant science findings have now been published.4 We provide here a more complete analysis of estimated benefits from reductions in troposphere ozone based on the final results of the NCLAN plant science research. In doing so, we concentrate on improvements in the modeling and underlying data which are reflected In this current assessment. While uncertainties still remain, these improvements should result in more defensible estimates of the magnitude of ozone’s effects on U.S. agriculture. 相似文献