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511.
George Provenzano 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1193-1199
This paper presents a simple method which utilizes composite emission factors to estimate motor vehicle lead emissions for large areas. Composite emission factors incorporate information on vehicle lead emission rates, sales-weighted average fuel economies, annual vehicle travel fractions, and average gasoline lead concentrations. The lead emissions estimation procedure takes as given estimates of motor vehicle travel and, hence, can be applied to any region or road system for which current or projected travel estimates are available. Estimates of motor vehicle lead emissions for major highway systems in individual states and national forecasts of motor vehicle lead emissions for six potential scenarios regarding the future use of lead additives in gasoline are presented to demonstrate the application of the method. 相似文献
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Dennis F. Kahlbaum Jon M. Heuss George T. Wolff 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1070-1078
ABSTRACT Because the U. S. Environmental Protection Agency (EPA) has changed the National Ambient Air Quality Standards (NAAQS) for ambient particulate matter (PM), there is a great deal of interest in determining recent PM trends. This paper examines trends in PM10 (i.e., particulate matter less than 10 micrometers in diameter) for areas of the United States based on their attainment status—for PM10 and ozone nonattainment and attainment areas. The analysis also focuses on urban, suburban, and rural areas, and eastern and western areas. The time period of evaluation is from 1988 through 1995. To shed further light on the ambient PM10 trends, trends in ambient SO2, NO2, and volatile organic compounds (VOCs) are also analyzed. Finally, trends in emission inventories of SO2, NOx, VOCs, and PM10 are evaluated. Results of the analysis show that widespread and similar reductions in PM10 levels have occurred over the last seven years. Annual reductions range from 3.0% to 3.8%, with the greatest reductions coming in PM10 nonattainment areas, but with very significant reductions also in PM10 attainment areas, ozone attainment areas, and rural areas. The widespread reductions appear to be due to a set of controls or common factors that are having a fairly uniform effect in all of the areas. The consistency of the reductions in different areas suggests that the reductions may also be primarily in the fine particles (i.e., those less than 2.5 micrometers in diameter, or PM2.5), which are more readily transported than coarse particles. 相似文献
513.
Avraam Karagiannidis George Perkoulidis Agis Papadopoulos Nicolas Moussiopoulos Thomas Tsatsarelis 《Waste management & research》2005,23(4):381-388
The lifespan of electric and electronic equipment is becoming shorter and the amount of related waste is increasing. This study aimed to contribute to the knowledge about qualitative and quantitative characteristics of such wastes in Greece. Specifically, results are presented from a field survey, which took place in the city of Thessaloniki, Greece, during the year 2002. The survey was conducted with suitable questionnaires in department stores and in households of various municipalities. Household appliances were grouped as follows: (A) large (refrigerator, freezer, washing machine, clothes dryer, electric cooker, microwave oven, electric heater), (B) small (vacuum cleaner, electric iron, hair dryer), (C) information technology and telecommunication equipment (PC, laptop, printer, phone) and (D) consumer equipment (radio, TV, video, DVD, console). The analysis indicated that the lifespan of all new goods is gradually reducing (apart from refrigerators, for which the lifespan was surprisingly found to be increasing) and provided linearized functions for predicting the lifespan, according to the year of manufacture, for certain large appliances. 相似文献
514.
Landsat Thematic Mapper: Detection of Shifts in Community Composition of Coral Reefs 总被引:1,自引:0,他引:1
Abstract: We assembled a time series of 20 Landsat thematic mapper images from 1982 to 1996 for Key Largo, Florida, to ascertain whether satellite imagery can detect temporal changes in coral reef communities. Selected reef and control areas were examined for changes in brightness, spectral reflectance, band ratios, spatial texture, and temporal texture ( pixel-to-pixel change over time). We compared the data to known changes in the reef ecosystem of Carysfort Reef and terrestrial sample sites. Changes in image brightness and spectral-band ratios were suggestive of shifts from coral- to algal-dominated community structure, but the trends were not statistically significant. The spatial heterogeneity of the reef community decreased in the early 1980s at scales consistent with known ecological changes to the coral community on Carysfort Reef. An analysis of pixel-scale variation through time, termed temporal texture, revealed that the shallow reef areas are the most variable in regions of the reef that have experienced significant ecological decline. Thus, the process of reef degradation, which alters both the spatial patterning and variability of pixel brightness, can be identified in unclassified thematic mapper images. 相似文献
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Estimating the Carbon Content of Russian Forests; A Comparison of Phytomass/Volume and Allometric Projections 总被引:1,自引:0,他引:1
Hamburg Steven P. Zamolodchikov Dmitri G. Korovin George N. Nefedjev Viktor V. Utkin Anatoly I. Gulbe Jakov I. Gulbe Tatjana A. 《Mitigation and Adaptation Strategies for Global Change》1997,2(2-3):247-265
Mitigation and Adaptation Strategies for Global Change - As increased attention is being paid to the role Russian forests play in the global carbon budget, the desirability of being able to... 相似文献