共查询到20条相似文献,搜索用时 31 毫秒
1.
Vukovich FM 《Journal of the Air & Waste Management Association (1995)》2000,50(12):2067-2072
This study examined the spatial distribution of the weekday/weekend difference in Baltimore, MD, and vicinity. The difference in Baltimore was characterized by having approximately 39% more NOx, approximately 59% more CO, and approximately 27% more volatile organic compounds (VOCs) on the average weekday, but there was approximately 13% more O3 on the weekend day. Spatially, the difference was elongated in the northeast-southwest direction. It decreased from 13% more O3 in Baltimore to 6% at approximately 20 km west of Baltimore and to 4% at approximately 40 km south of Baltimore. It also appeared to decrease to the east, but the magnitude of the decrease could not be determined because of the lack of data east of the Chesapeake Bay. However, the difference increased to the north, reaching a value of almost 18% at a northern Delaware site. 相似文献
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Fred M. Vukovich 《Journal of the Air & Waste Management Association (1995)》2013,63(12):2067-2072
ABSTRACT This study examined the spatial distribution of the weekday/weekend difference in Baltimore, MD, and vicinity. The difference in Baltimore was characterized by having ~39% more NOx , ~59% more CO, and ~27% more volatile organic compounds (VOCs) on the average weekday, but there was ~13% more O3 on the weekend day. Spatially, the difference was elongated in the northeast-southwest direction. It decreased from 13% more O3 in Baltimore to 6% at ~20 km west of Baltimore and to 4% at ~40 km south of Baltimore. It also appeared to decrease to the east, but the magnitude of the decrease could not be determined because of the lack of data east of the Chesapeake Bay. However, the difference increased to the north, reaching a value of almost 18% at a northern Delaware site. 相似文献
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Schifter I Díaz L López-Salinas E Rodríguez R Avalos S Guerrero V 《Journal of the Air & Waste Management Association (1995)》2000,50(2):301-309
The environmental agency in the metropolitan area of Mexico City has launched a program to introduce more energy-efficient modes of transport, one of which is the use of alternative and less polluting fuels. With the perspective in mind, a liquefied petroleum gas (LPG) fleet of vehicles is exempt of the mandatory "one day without a car" program if the emission of pollutants is below the standard authorized for that specific purpose. Today, about 28,000 light-duty vehicles and heavy-duty trucks circulate in the area, most of them as aftermarket converted vehicles. In this work, we evaluated regulated exhaust emission and other parameters on 134 representative vehicles of that fleet. From the data obtained, an estimate of emission factors and their contribution to the global emission in the metropolitan area is provided. It is concluded that more than 95% of the in-use vehicles using LPG presented regulated emissions which exceeded in one or more the environmental regulations values required for certification. The poor maintenance of the vehicles and the type of conversion kit installed could be the culprits of the results obtained. 相似文献
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Saxena PK Singh VP Kondal JK Soni GL 《Environmental pollution (Barking, Essex : 1987)》1989,58(4):273-280
In vitro incorporation of (14)C-glucose/acetate into lipids and (14)C-leucine into proteins by the liver of Channa punctatus, exposed to safe application rate (SAR) and sublethal (SL) concentrations of malathion and carbaryl for 30 days (mid-February to mid-March) during the preparatory phase of the reproductive cycle, declined more in the fish exposed to SL concentrations than to SAR concentrations of the pesticides. The decline in incorporation was more marked in the malathion-exposed fish, than in those exposed to was more marked in the malathion-exposed fish, than in those exposed to carbaryl. Hence, malathion is considered more toxic than carbaryl in inhibiting the de-novo synthesis of lipids and proteins by the liver. 相似文献
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Gambino Edvige Chandrasekhar Kuppam Nastro Rosa Anna 《Environmental science and pollution research international》2021,28(24):30436-30451
Environmental Science and Pollution Research - Marine pollution is becoming more and more serious, especially in coastal areas. Because of the sequestration and consequent accumulation of... 相似文献
7.
Isaac Schifter Luis Díaz Esteban López-Salinas Rene Rodríguez Sergio Avalos Victor Guerrero 《Journal of the Air & Waste Management Association (1995)》2013,63(2):301-309
ABSTRACT The environmental agency in the metropolitan area of Mexico City has launched a program to introduce more energy-efficient modes of transport, one of which is the use of alternative and less polluting fuels. With that perspective in mind, a liquefied petroleum gas (LPG) fleet of vehicles is exempt of the mandatory "one day without a car" program if the emission of pollutants is below the standard authorized for that specific purpose. Today, about 28,000 light-duty vehicles and heavy-duty trucks circulate in the area, most of them as aftermarket converted vehicles. In this work, we evaluated regulated exhaust emission and other parameters on 134 representative vehicles of that fleet. From the data obtained, an estimate of emission factors and their contribution to the global emission in the metropolitan area is provided. It is concluded that more than 95% of the in-use vehicles using LPG presented regulated emissions which exceeded in one or more the environmental regulations values required for certification. The poor maintenance of the vehicles and the type of conversion kit installed could be the culprits of the results obtained. 相似文献
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The Costs of Meeting the Environmental Objectives for the Baltic Sea: A Review of the Literature 总被引:1,自引:0,他引:1
Katarina Elofsson 《Ambio》2010,39(1):49-58
The environmental targets of the recently agreed Baltic Sea Action Plan (BSAP) targets are likely associated with a considerable
cost, which motivates a search for low-cost policies. The following review shows there is a substantial literature on cost-efficient
nutrient reduction strategies, including suggestions regarding low-cost abatement, but actual policies at international and
national scale tend to be considerably more expensive due to lack of instruments that ensure a cost-efficient allocation of
abatement across countries and sectors. Economic research on the costs of reducing hazardous substances and oil spill damages
in the Baltic Sea is not available, but lessons from the international literature suggest that resources could be used more
efficiently if appropriate analysis is undertaken. Common to these pollution problems is the need to ensure that all countries
in the region are provided with positive incentives to implement international agreements. 相似文献
10.
《Chemosphere》1986,15(3):309-315
Pentachlorophenol, depending on the applied concentration, reduces the activity of some microorganisms, as measured by the iron reduction test. The test is more sensitive, if the procedures reported in literature are modified, including the use of glucose as a source of energy instead of yeast extract. 相似文献
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Various surfactants belonging to the group of fatty acid-acylated amino acids were tested for their ability to accelerate the microbial degradation of mineral oil. Of the lauric acid-acylated amino acids, aliphatic acids and histidine were found to be the most suitable. By the aid of these compounds additional 20-60% of a residual oil fraction could be degraded. The longer the chain of the fatty acid moiety, the more effective the surfactants are. Natural L-amino acids were more effective than their D-configuration. Since the special surfactants are easily biologically degradable, multiple replenishment is required in long-term experiments. The faster, more complete degradation of mineral oil is caused solely by interfacial activity; the growth of biomass due to the function of surfactants as substrate had no effect. 相似文献
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Low pH markedly reduced heterotrophic microbial activity in sediment-lake water systems. A marked reduction in both the rate and the total amount of oxygen consumed occurred as pH decreased. In addition, low pH and also low temperature (0°C) resulted in longer turnover times (Tn) and also smaller Vmax values when the kinetics of 14C-glucose, 14C-glycine, and 14C-glutamic acid utilization were examined. When the response of the microorganisms to heavy metals was examined, mercury was generally more toxic than lead over the pH range of 4.5 to 7.5 but both metals were more toxic at pH 4.5 than at higher pH levels. Mercury also inhibited oxygen utilization and 14C-glucose mineralization more than lead at all pH levels. Bisulfite reduced microbial activity at all pH levels although it was always more toxic to the sediment microorganisms at pH values of 4 and 5 than at pH 7. 相似文献
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公路周边土壤重金属污染及植物修复 总被引:1,自引:0,他引:1
随着中国公路建设迅猛发展,公路周边土壤重金属污染也日趋严重。文中结合近年来国内外的研究情况,以公路土壤污染中的铅、镉、锌、铜、铬等元素为重点,对土壤重金属污染的危害、分布特征及其影响因素,以及相应的植物修复技术等相关研究进行综述。 相似文献
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Xin Meng Xin-gang Zhao 《Environmental science and pollution research international》2022,29(23):34092-34104
Environmental Science and Pollution Research - With the process of China’s economic transformation and structural adjustment, the trend of thermal power industry transfer is more and more... 相似文献
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The potential soil phytotoxicity in the surroundings of an old zinc smelter closed in 1966, was evaluated by a biological test system. This system is based on the analysis of shoot growth and (iso-) enzymes in leaves and roots of 2-week-old seedlings of Phaseolus vulgaris grown on soil samples under controlled environmental conditions. The biological data were presented in a phytotoxicity index, which allowed classification of the soil samples into four phytotoxicity classes. Comparison was made between the biological results and soil and plant metal content. The study revealed that more than 20 years after closure of the factory, the soils in its surroundings were still potentially phytotoxic. Zinc proved to be the most important, but not the only, phytotoxic element, as was shown by isozyme analysis and by the strong correlation between the biological data, the water soluble Zn fraction of the soil and leaf Zn content. The effect of contamination extended to a distance of more than 3 km from the industrial site in the direction of the prevailing wind. 相似文献
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N. Hattab M. Soubrand R. Guégan M. Motelica-Heino X. Bourrat O. Faure J. L. Bouchardon 《Environmental science and pollution research international》2014,21(17):10470-10480
The efficiency of aided phytostabilization using organic amendments such as ramial chipped wood (RCW) and composted sewage sludge (CSS) was studied on contaminated techno-soils, on nine experimental plots. The objective was to characterize the role of fulvic (FA) and humic acids (HA) on the mobilization of trace elements, specifically As, Cu, Mo, Pb and Zn. Results showed that the addition of CSS increased the total organic carbon and nitrogen content more than with RCW and as a result, the C/N ratio in the CSS soil was higher than in the RCW and non-amended (NE) soil, reflecting the high decomposition of soil organic matter in the CSS soil compared with the other soils. The RCW and CSS amendments increased the hydrogen index (HI) values and the oxygen index (OI) values compared with the NE soil, especially for the soil treated with CSS which contained more aliphatic than aromatic compounds. The addition of CSS to the techno-soil significantly increased the percentage of C org associated with the HA fractions compared with the RCW and NE soils. The soil amended with CSS showed the highest E 4/E 6 ratio and the lowest E 2/E 3 ratio of FA. Zn and As were more abundant in the FA fraction than in the HA fraction, whereas Pb, Cu and Mo were more associated to HA than to FA in the treated and untreated soils, which may explain the difference in their mobility and availability. 相似文献