Abstract: The spatial distribution and temporal concentration variation of a set of gaseous air components (e.g., CO2, CO, H2CO, H2O) have been monitored with a multi-channel photoacoustic gas-analyzer in an urban church ( Saint Catherine's, Cracow) and a mountain church ( Saint Michaels Archangel, Szalowa) of Poland, in order to assess the likely effects of air pollution indoors under the influence of provisory electrical infrared (IR) heaters and without heating. Likewise, the ventilation characteristic and the leakage of these buildings with different constructions (i.e., plastered stone and wooden structures) with the assistance of decay curves of SF6 tracer gas was evaluated and compared. The wooden building in Szalowa, due to its more open structure, developed about one order higher ventilation rates (e.g., 0.9-1.3 h(-1)) than the stone church in Cracow (e.g., 0.1 h(-1)). The IR-heating affected only modestly the ventilation rate of the wooden church (e.g., 1.2-1.6 h(-1)), but it increased significantly that of the plastered stone church (e.g., 0.27 h(-1)). The ventilation rates were also assessed with the use of the CO2 curve decay method, and satisfactory agreement was found with those observed by the use of SF6 tracer. The spatial distribution of the studied gaseous pollutants (CO2, H2O) was found to be in some occasions nonhomogeneous in both buildings, due to the active usage of the IR-heating, especially, during a couple of consecutive liturgical services. Besides the pollution events due to ingress of gaseous air pollutants, present at enhanced levels outdoors, increased CO, CO2 and H2CO peaks were observed indoors too, which, in most cases, could be associated with incense burning. (C) 2018 Elsevier Masson SAS. All rights reserved.

Abstract: Elemental and water-soluble ionic compounds (WSICs) of atmospheric aerosols (total suspended particulate TSP) and some gaseous pollutants (SO2, NO2 and O3) from a coastal, semi-urban and rural site in and near Dar es Salaam, Tanzania were investigated during dry and wet seasons of January 2005November 2007. Na+, Ca2+, SO42−, NO3− and Cl− made up the dominant fraction of WSICs during the dry season with average concentrations ranging from non-detectable (n.d.)5.4, 0.262.6, 0.7414.7, 0.41.5 and 1.13.4 μg m−3, respectively, while in the wet season, from n.d. up to 1.7, 1.2, 4.4, 2.1 and 3.0 μg m−3, respectively. The total air concentrations of the detected elements (Al, Si, S, Cl, K, Ca, Fe and Zn) showed seasonal and site-specific variation in the range of 7.526.6 with an average of 14.5 μg m−3. Most of the air concentrations of pollutants were observed to decrease with increasing distance from the coastal site, which is under urban and industrial pollutant emissions. Sulphur and nitrogen oxidation ratios during the dry season ranged from 0.08 to 0.91 and 0.013 to 0.049, respectively, while they were between 0.090.65 and 0.0020.095, respectively, in the wet season. These values indicate the photochemical oxidation of SO2 and a high extent of NO3−formation in the atmosphere. Neutralization ratios revealed the presence of acidic SO42− and NO3− aerosols. Principal component analysis identified sea spray, local combustion, vehicular traffic, biomass burning and re-suspended road dust as dominant sources of aerosols at the studied coastal and semi-urban sites. However, at the rural site, besides sea spray, crustal sources, soil dust re-suspension and long-range transport are the possible origins of suspended particulates.

Abstract: Cellulose filters with immobilized 2,2'-diaminodiethylamine (DEN) functional groups are studied for trace anion preconcentration from aqueous solution, with subsequent x-ray fluorescence measurements. For most oxoanions with a central metal atom, nearly quantitative collection can be achieved by 10-cm2 DEN filters under the following optimized conditions: pH 36, filtration rate up to 0.5 ml cm-2 min-1, and sample volume up to 100 ml cm-2. The collection yield is independent of the trace oxoanion concentration up to at least 1.5 μmol cm-2. Although the DEN filter exhibits some selectivity towards oxoanions with a central metal atom, ionic strength affects the results; the collection efficiency is strongly depressed with salt (e.g. NaCl) concentrations above 0.01 M. The applicability of the DEN filter in anion collection is therefore limited to dilute solutions.