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On frequency distributions of air pollutant concentrations
Atmospheric Environment (1967), 1976Abstract Observed frequency distributions of air pollutant concentration levels are critically analyzed with respect to their statistical description. It is demonstrated that several common distributions can be used to fit observed data, one of which is the popular log-normal distribution.
Bencala, Kenneth E., Seinfeld, John H.
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Statistical distributions of air pollutant concentrations
Environmental Science & Technology, 1982Air pollutant concentrations are inherently random variables because of their dependence on the fluctuations of a variety of meteorological and emission variables. When sets of air quality data are available, various statistical characteristics can be determined and assigned to the pollutant concentrations.
Georgopoulos, Panos G. +1 more
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ELECTRETS TO MEASURE ION CONCENTRATION IN AIR
Health Physics, 2005Positive and negative ions are produced in air, mainly due to radon and terrestrial/cosmic radiation sources. Measuring ion concentration in air indirectly provides a measure of these sources. Electrets (electrically charged pieces of Teflon), when exposed in the environment, collect ions of opposite sign leading to a measurable decrease in charge ...
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[Concentration of imidazolines in the air].
Meditsina truda i promyshlennaia ekologiia, 1996Using chamber for adjustable mode and dosing apparatus, the authors studied conditions of imidazolines' condensation from the air into 60% ethanol, to paper filters of "white tape" type, to analytic filters of AFA-HP type, into a shell with ultrathin layer of sorbent (2.7% sulfuric acid in 20% solution of glycerine in water).
L I, Trubnikova, V N, Maĭstrenko
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Concentrator for solar air heater
Applied Physics, 1979A focusing collector for air heater, the concentrator being Fresnel lenses, is here examined. The sunlight is focalized on black-body metallic sheets, contained in an insulated box, through which the energy is transferred to the fluid (dry air). The sheets, having the same height, are arranged at a distance one from another increasing from the center ...
F. Demichelis, E. Minetti-Mezzetti
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Air Pollution: Sources, Concentrations and Measurements
2007In this chapter, the basic concepts of particulate and gaseous, and primary and secondary pollutants are introduced. Consideration is then made of the sources, properties and measurement of the following specific air pollutants: sulfur dioxide, suspended particulate matter, oxides of nitrogen, carbon monoxide, hydrocarbons, ozone and peroxyacetyl ...
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Calculating pollen concentration of the air
Journal of Allergy, 1937Abstract 1.1. Scheppegrell's table for velocities of fall in feet per second was incorrectly calculated, as a result many reports of pollen concentration per cubic yard based on his formula are much too low. 2.2. For scientific accuracy the actual size of each pollen grain should be considered in calculating pollen concentration of the atmosphere ...
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Mercury concentrations in Zagreb air
Environmental research forum, 1997The results are presented of a pilot study on mercury concentration levels in Zagreb air, measured over a five month period at two sites: one close to traffic and the other in a backyard. The preliminary results indicate that the significantly higher concentration levels are related to the vicinity of traffic and to weekdays.
Vađić, Vladimira +2 more
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Deregulation and Concentration in air transportation
1986Proceedings of the Transportation Research Forum – 27th ...
Adrangi, Bahram +5 more
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Emissions and Ambient Air Concentrations
1985The impact of precursor emissions on oxidant formation in the atmosphere may in principle be assessed on the basis of emission inventories. In the assessment, a correlation must be found between emission rates and ambient air concentrations of precursors, which depend on transport, dispersion, and chemical conversion of the precursors in the atmosphere.
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