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181.
Xiaowei Jin Yeyao Wang John P. Giesy Kristine L. Richardson Zijian Wang 《Environmental science and pollution research international》2014,21(1):61-66
While more developed countries have a well-established systems to develop water quality criteria (WQC), little research has been done on the adequacy of the current WQC to protect endemic species of China. In order to maintain the health of aquatic ecosystems in China, a series of projects to establish national WQC based on regional characteristics has recently been initiated. However, the establishment of a completely novel methodology would be costly and time consuming. Also, due to the similarities in physiologies and natural histories of classes of aquatic organisms, there is no reason to believe that WQC would not be sufficient to protect unique species in China. This review was undertaken to identify key outstanding issues regarding establishment of aquatic life criteria (ALC) to be applied in China, including prioritization of chemicals, test species, mode of action, field/semi-field data, and methods of aggregating the information and calculating the ALC. This was used to identify the principle issues that need to be addressed in order to better understand the methods for development of criteria for the protection of aquatic life and provide a reference to China and other developing countries committed to the establishment of their own WQC system. 相似文献
182.
183.
Walter W. Heck John A. Dunning 《Journal of the Air & Waste Management Association (1995)》2013,63(2):112-114
The sensitivity of tobacco and/or pinto bean to ozone, as an air pollutant, is increased by growing plants in a shortened photoperiod under reduced light intensity and in a light potting mix. Sensitivity also is influenced by carbon dioxide concentration, time of day, and age of plant at time of exposure. Plants are more severely injured by a given dose under continuous exposure than when the exposure is split into two time periods. Tobacco shows cumulative development of injury when exposed to low concentrations intermittently over several days. 相似文献
184.
Walter W. Heck John A. Dunning I. J. Hindawi 《Journal of the Air & Waste Management Association (1995)》2013,63(11):511-515
Before potential damage to vegetation can be adequately forecast, even after an air pollution alert has been placed in effect, a clear understanding of the interactions of environment on plant sensitivity must be ascertained. This involves detailed study of single factors and then multiple factors using the phytotoxicants in question. Factors studied or suggested include light (quality, intensity, and duration), temperature, carbon dioxide concentration, humidity, wind, soil moisture, soil aeration, nutrient levels, and soil texture. This paper presents a review of the work relating plant injury to specific air pollutants as conditioned by several environmental conditions supported by research on the interactions of ozone with these environmental conditions. 相似文献
185.
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
186.
John C. Elston Richard G. Kolb Irmin . Kamm John N. Pattison 《Journal of the Air & Waste Management Association (1995)》2013,63(10):767-772
This paper reports on the research program undertaken by the State of New Jersey to determine those tests and instruments which can be used by authorized state agencies for the enforcement of diesel smoke emissions. The state agencies under consideration for the enforcement of diesel smoke emissions are the following: (1) The Division of Motor Vehicles, in its system of state owned inspection stations, will be able to inspect all diesel-powered trucks, and tractors which are registered in New Jersey. (2) The Public Utilities Commission will be able to inspect at their home garages all buses registered in the State. (3) The New Jersey State Police will be able to inspect diesel-powered vehicles on the road. It was decided that the maximum inspection time for each vehicle was not to exceed one minute. On the basis of the one minute per vehicle requirement, eight different tests were evaluated to determine which ones correlated well with normal vehicle operation. These tests included acceleration of a fixed external inertia, free acceleration of only the moving parts of the engine, three ramp tests, a test in which a heavy vehicle was towed, and a driving test in which the vehicle being tested was actually accelerated. The results of tests demonstrated that the modified free acceleration method correlates reasonably well with a loaded steady state cycle, distinguishes the high emitters and is simple to perform. Consequently, the free acceleration test method is recommended for use in inspection stations and on the road. Finally, nearly two hundred vehicles have been tested by this procedure to determine present and potential levels of diesel smoke emissions. Another phase of the program consisted of the determination of smoke measuring techniques and instrumentation. The use and design of smokemeters were extensively investigated, as well as the use of the visual and photographic techniques. Of the various smokemeters tested for this application, several measured smoke satisfactorily in the laboratory, but none were found adequate for field use; they either lacked portability or were unstable due to the deposition of soot on the optics. At the time of writing, specifications for the necessary smokemeter have been drafted and published for bid to interested manufacturers. 相似文献
187.
A feature of the 63rd annual meeting of the Air Pollution Control Association, held June 14–18, 1970 in St. Louis, was a plenary session on national emission standards. Presided over by John S. Lagarias, APCA past president, the session explored the theme for both motor vehicles and stationary sources through the presentations of Delbert S. Barth and Arthur C. Stern and the discussions of John A. Maga and Robert L. Harris, Jr. The essence of their remarks appears on the following pages. 相似文献
188.
Harold I. Nudelman John A. Frizzola 《Journal of the Air & Waste Management Association (1995)》2013,63(2):140-144
In January 1971, the New York City area experienced a period of high pollution in which concentrations exceeded the present criteria for Stage I of the New York City Alert-Warning System. The incident was unusual because the high concentrations were associated with a weak frontal system which moved back and forth over the area and not with a stagnating anticyclone. Concentrations of pollutants were found to be closely related to the movement of the frontal system as well as to changes in wind speed and stability. Climatological criteria for identifying-periods of potential high air pollution and the criteria for mixing heights, transport wind speed and ventilation factors necessary for the issuance of an official advisory from the National Meteorological Center were not met during this incident. Therefore, some re-evaluation and redefinition of these criteria are recommended. 相似文献
189.
A. David Rossin John J. Roberts 《Journal of the Air & Waste Management Association (1995)》2013,63(4):254-259
With respect to health effects and types of emission sources, carbon monoxide is different from SO2 and airborne participates. The effects of nontoxic CO levels are temporary and reversible. The primary sources are automobiles and trucks, and concentrations are often highly localized. Episode control strategies developed for other pollutants are not applicable for coping with CO episodes. 相似文献
190.
John M. Bownds 《Journal of the Air & Waste Management Association (1995)》2013,63(4):210-213
Assuming the existence of an ambient air standard for a given pollutant, there is some agreement that emission standards for local area and point sources should be established by formulating and testing various “control strategies” with use of a computer diffusion model. The procedure requires several, perhaps many, computer simulations of pollutant dispersion followed by an analysis of the results of each simulation. Part of this analysis is to include an “optimization” of sorts which is intended to provide a workable control strategy which, in turn, is to indicate required emission level reductions for point sources. This paper is intended to describe and apply an approximation technique which, when used in conjunction with a diffusion model, could be of value in determining acceptable emission levels for point sources. 相似文献