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831.
A study was made of the composition of wastes collected from the pipes of the stormwater drainage system of Sorocaba, SP, Brazil (600 thousand inhabitants). A total of 10 samples weighing at least 100 kg each were sorted into 19 items to determine the fraction that can be considered natural (earth/sand, stones, organic matter, and water, the latter determined after oven-drying the samples) and the anthropogenic fraction (the remaining 15 items, especially construction and demolition wastes and packaging). Soil/sand was found to be the main item collected (52.5 % dry weight), followed by the water soaked into the waste (24.3 %), which meant that all the other wastes were saturated in mud, whose contents varied from 6.4 % (glass) to 87.2 % (metalized plastics packaging). In general, 83 % of the collected wastes can be classified as “natural,” but the remaining 17 % represent 2,000 kg of the most varied types of wastes discarded improperly every day on the streets of the city. This is an alarming amount of wastes that may clog parts of the drainage systems, causing troubles for all the population (like flooding) and must be strongly considered in municipal solid wastes management and in environmental education programs.  相似文献   
832.
This paper analyzes the Cuban model of sustainable development and explains the causes that made Cuba the only country that meets the conditions of sustainability according to the Worldwide Fund for Nature (WWF). The Human Development Index has three main components: quality of life (health indicator measured as life expectancy at birth), knowledge (education indicator measured as adult literacy) and the standard of life (economic indicator measured by the Gross Domestic Income). This paper analyses the aspects of the educational and health system of Cuba and also of its energy policies that explain the excellent scores of the Human Development Index. Cuba shows a Human Development Index of 0.8 with an Ecological Footprint of 1.8?gha. This is achieved with a Gross Domestic Income lower than other countries with similar Human Development Index. The Ecological Footprint of Cuba is mainly determined by the CO2 and the agricultural land footprint. The paper shows how the economic transition, after the economic crisis of the early 1990s, was realized without significantly increasing the Ecological Footprint.  相似文献   
833.
Leaves of Tendergreen bean plants exposed to atmospheric fluoride concentrations in the range 1.7 to 7.6 μg/m3 showed increased levels of enolase and catalase activity and decreased levels of pyruvate and α-ketoglutarate. Phosphoenolpyruvate carboxylase activity and oxalacetate were not affected. The leaves of Milo maize plants exposed to 5.0 μg F/m3 showed increased levels of enolase and pyruvate kinase activity and a decreased level of pyruvate. Oxalacetate and α-ketoglutarate levels were not affected. Catalase activity was increased, then decreased by IIF fumigation. The changes induced by HF were greatest six to 10 days after the start of fumigation and disappeared or decreased in magnitude during the post-fumigation period.  相似文献   
834.
This is a report on Meetings of Representatives of National Air Pollution Preventions Associations to Consider the Establishment of an International Union, held in Washington, D. C, June 18–19, 1964 and Houston, Texas, June 21–22, 1964.  相似文献   
835.
836.
An urban diffusion model, which does not require the use of an electronic computer, is presented. The main simplifying assumptions are that continuous pollutant sources are uniformly distributed over the urban area and vertical diffusion occurs until the effluent from each line source reaches the top of the mixing layer, after which the effluent is uniformly distributed through the mixing layer. After the appropriate vertical diffusion coefficient is specified, the calculated concentration is a function of source strength, linear dimension of the metropolis, mixing depth, and wind speed. The calculated concentration is interpreted either as a representative maximum concentration or, through integration, as the average concentration over the metropolitan area. When a representative pollutant concentration is known, the model may be used to determine the apparent “uniform” source strength.  相似文献   
837.
Current-voltage relationships for negative corona are given for a pilot-scale electrostatic precipitator with 3-in. electrode spacing at 80°–1500°F and 35–80 psig. Direct comparison is made with the electrical characteristics for a 1-in. spacing at 1200°F over the same pressure range. Experimental results on both spacing agree well with electrostatic theory. Initial dust removal efficiencies for the pilot-scale precipitator ranged from 90 to 98% at 1460°F and 80 psig, but continuous operation was not achieved owing to excessive thermal expansion of the internal parts of the unit.  相似文献   
838.
In conjunction with a 15-month air quality survey of Jacksonville, Fia., a mathematical model has been developed to describe the dispersion of atmospheric pollutants. The source inventory used with the model was compiled, in part, from the data obtained from the sampling of all major sources within the area. The major sources were considered separately from the one-mile square area sources which accounted for the remainder of the emissions. Meteorological data was recorded continuously in the city including vertical temperature observations to 750 ft. The model was compiled in FORTRAN and can be used for both gaseous and particulate pollutants, by utilizing proper decay rates. The variant nature of meteorological parameters and emission rates are considered. The ground level concentrations of several pollutants which were determined for 24 hr periods at 11 sites and continuously at two other sites were used to check the model. A limited tracer study was carried out in conjunction with the project.  相似文献   
839.
A system has been developed to automatically measure the effects of air pollutants in the ambient air on the rate of CO2 exchange by intact leaves of citrus trees growing in the field. A miniaturized system utilizing the same nondispersive infrared CO2 analyzer has been designed to study individually the effects of different concentrations of air pollutants on photosynthesis and respiration by plants.  相似文献   
840.
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   
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