background: air pollution and concerns about health impacts have been raised in metropolitan cities like tehran. trend and prediction of air pollutants can show the effectiveness of strategies for the management and control of air pollution. artificial neural network (ann) technique is widely used as a reliable method for modeling of air pollutants in urban areas. therefore, the aim of current ...

The selective reduction of sulfur dioxide with carbon monoxide to elemental sulfur was studied over ACsupported transition-metal oxide catalysts. According to the study, Fe2O3 /AC was the most active catalyst among the 4 AC-supported catalysts tested. By using Fe2O3 /AC, the best catalyst, when the feed conditions were properly optimized (CO/SO2 molar ratio = 2:1; sulfidation temperature, 400 ◦...

Sulfur-bearing compounds are very detrimental to the environment and to industrial process equipment. They are often obtained or formed as a by-product of separation and thermal processing of fuels containing sulfur, such as coal, crude oil and natural gas. The two sulfur compounds, which need special attention, are: hydrogen sulfide (H2S) and sulfur dioxide (SO2). H2S is a highly corrosive gas...

BACKGROUND Measurements of nitrogen and sulfur dioxide using passive sampler over 12 months in Samsun, Turkey, are compared with SO2 and NO2 concentrations obtained from a co-located chemiluminescence analyzer. The concentrations of Sulfur and nitrogen dioxide in the ambient air during the period from November 2009 to September 2010 are analyzed. RESULTS The highest value for annual NO2 and S...

We used a combination of experiments and molecular simulations to investigate at the molecular level the effects of zeolite structure on the adsorption and diffusion of sulfur dioxide, carbon dioxide and carbon monoxide as well as separation processes of their mixtures. Our study involved different zeolite topologies and revealed numerous structure-property trends depending on the temperature a...

The present climate of Venus is controlled by an efficient carbon dioxide–water greenhouse effect and by the radiative properties of its global cloud cover. Both the greenhouse effect and clouds are sensitive to perturbations in the abundance of atmospheric water vapor and sulfur gases. Planetary-scale processes involving the release, transport, and sequestering of volatiles affect these abunda...

Fromm et al. and Vernier et al. suggest that their analyses of satellite measurements indicate that the main part of the Nabro volcanic plume from the eruption on 13 June 2011 was directly injected into the stratosphere. We address these analyses and, in addition, show that both wind trajectories and height-resolved profiles of sulfur dioxide indicate that although the eruption column may have ...

Traditionally, measures designed to reduce localized ground-level concentrations of sulfur oxides (SOx) used high-level dispersion. Although these measures reduced localized health impacts, it is now realized that sulfur compounds travel long distances in the upper atmosphere and can cause damage far from the original source. Therefore the objective must be to reduce total emissions. The extent...