Showing papers on "Air pollutant concentrations published in 1983"

Higher Plants as Indicators and Accumulators of Gaseous Air Pollution

Abstract: Some higher plant species or varieties are very sensitive to certain gaseous air pollutants, and the resulting effects show sometimes more or less specific, well-visible and measurable symptoms.

A Study of the Potential Impact of Some Unregulated Motor Vehicle Emissions

Abstract: Studies of emissions from vehicles equipped with catalysts have shown that some unregulated emissions can increase when a catalyst is used One example of this is sulfuric acid, which has been studied extensively Other unregulated emissions include ammonia and hydrogen cyanide In a number of studies, these unregulated pollutant emissions have been measured from light-duty vehicles and heavy-duty engines These emission levels were used in air quality dispersion models to predict the resultant air quality levels The ambient concentrations predicted for each pollutant were then compared to suggested concentrations at which adverse health effects may be found to determine if additional monitoring or control would be indicated for these pollutants It was determined that mobile source emissions of sulfuric acid, hydrogen cyanide, and ammonia do not in general result in ambient levels of concern for the air quality situations studied

Air pollution emission profiles of toxic and trace elements from energy related sources: status and needs.

Abstract: The preceding was by no means a comprehensive analysis on the present state of knowledge on trace elements in combustion sources, or the differences that would be expected. However, it does point to avenues and directions of some of the future research. Also, the needs 1) to resolve source in areas of great emissions complexity, or 2) to assign sources of specific hazardous materials. Current efforts are focussed on understanding the impact of particular sources of pollutants at a receptor site. This information will provide the means for assessment of any potential hazard of a source to the general community and the size and mass distribution of these materials at a receptor. Considering the types and volume of data necessary to catalog source types and eventually assess community impacts, the development of a national resource with far more sensitive and accurate multielement analysis of air pollutants is warranted. Interaction of air quality and nuclear analytical research groups in collaborative research projects should be fostered and commitments made to develop pools of large and small users.

Estimating mobile source pollutant emission: Methodological comparison and planning implications

Abstract: In the United States, the Clean Air Act Amendments of 1977 require that all non-attainment metropolitan areas evaluate the potential of transportation controls in meeting 1982 National Ambient Air Quality Standards. Many of these controls are designed to impact on mobile source emissions by altering vehicular speed. The paper discusses differences in results obtained by two alternative methods for estimating the same area's mobile source emissions. The findings suggest that alternative zonal speed aggregation procedures can lead to widely diverging emission estimates. The paper further discusses the inherent assumptions in the aggregation procedures and the potential consequences of their uses in transportation planning for air quality controls.

Air Pollution in the Republic of China (Taiwan)

Abstract: A brief summary of air pollution development on the island of Taiwan was presented. Four major factors have caused the air pollution concentration to increase: (1) the increase in the number of industries on the island; (2) the combustion of fuel oil, coal, and wood; (3) automobile exhaust emissions; and (4) high population density. The Bureau of Environmental Protection (BEP) under the Department of Health in the Executive Branch of the central government is empowered with overseeing environmental affairs and is responsible for enforcing and amending the environmental laws and regulations. Basically, the air pollution monitoring and control activities in Taiwan are in their preliminary stages. These developments have accomplished their goals of providing a general concept of air pollution status. The typical ambient air concentrations for dust, TSP, hydrocarbons, sulfur dioxide, H/sub 2/S, NO/sub 2/, CO, and O/sub 3/ are given. 1 figure, 1 table. (DP)

Reduction of Pollutant Formation in Combustion Processes

Abstract: Combustion sources account for approximately ninety percent of air pollutant emissions Many of the effects of air pollutants upon human health and the environment are reasonably well understood Some potential problems, however, such as the presence of carcinogens in urban atmospheres and the effect of carbon dioxide on climate, while not well understood, cause concern — Modification of combustion processes to reduce pollutant emissions has proven successful Better understanding of the fundamentals important to combustion often leads to pollutant reduction without compromise of efficiency or the quality of the combustion process Treatment of combustion products to remove pollutants also has proven effective in cases where combustion modification fails to yield the required reduction In other cases treatment of the fuel to remove pollutant percursors has been employed A combination of these approaches has been chosen as an optimum strategy for some pollution control situations

Air pollution and family health.

Abstract: Air pollution is classified according to chemical characteristics of the pollutants and sources: reducing air pollution, photochemical air pollution, point-source emission and indoor air pollution. The primary pollutants are particulates, oxides of sulfur and nitrogen, ozone, hydrocarbons, carbon monoxide and lead. A knowledge of the effects of these on healthy people and impaired patients can provide the physician with specific measures to apply in individual cases.

Analysis of Frequency Distributions of Air Pollutant Concentrations by Hybrid-lognormal Distribution (I)

Abstract: 大気汚染物質 の濃度分布 は対数正規 分布に従 うと仮定 して解析す る ことが 多いが,必 ず しも対数正規 分布に従 ってい るとは いえない場 合 も少 な くない。規制 のため の環 境 目標 値の設定等を考慮す ると,大 気汚染物質濃度へ適用す るため には,パ ラメー タが 増加 し少 々複雑 な分布 であ って も,そ のパ ラ メー タ が安 定 していれば,実 測 データに対 して適合 の よい分布を適用すべ きであ る。 放 射線 の被曝線量の分布 も大気 汚染物質 の濃 度分布 と同様 な特徴 を もつ が,こ の分布 モデルとして混 成対数正規 分布が提 案 され,そ の有効性が 検証 されてい る。そ こで,本 報告 では この混成対数正規分布 を大 気汚染物質の濃度分布へ適用すべ く,混 成対 数正規分布 の もつ 諸性質 を明 らかに し,大 気汚染物質 の濃 度分布 への適用の可能性の検討を行 った。 その結果,混 成対数正規分布は,確 率紙 上におけ る分布 曲線が 対数正 規分布 と正規分布 の間 にあ るよ うな分布 を表現す るのに適 した分布 であ り,大 気汚染物質 の濃度分布 の モデル として有効 である ことを 示 した。

Estimation of air pollutant concentrations by the Galerkin finite element method

Abstract: This paper is concerned with the estimation of air pollutant concentrations by solving the advection-diffusion equation using the Galerkin finite element method. The physical properties denoting the transport arid diffusion of the air pollution are assumed to be expressed by the two-dimensional advection-diffusion equation where the height of the stack is low and the vertical diffusion is small. The distributions of wind velocities and background concentrations are estimated using an interpolation method based on the observed data at monitoring stations. The Galerkin finite element method estimates the temporal and spatial distributions of air pollutant concentrations by solving the advection-diffusion equation. The estimation experiment of sulphur dioxide concentrations is carried out over the industrial area of Tokushima Prefecture, Japan, and the numerical results indicate the effectiveness of the proposed, method.