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Masowy rozkład pierwiastków w próbkach pyłu zawieszonego pobranych w obszarze tła miejskiego: wyniki ośmiomiesięcznych badań w Zabrzu

Rogula-Kozłowska W., Klejnowski K., Rogula-Kopiec P., Błaszczak B., Mathews B., Szopa S.

Rocznik Ochrona Środowiska

2013

Tom 15, cz. 2

1022--1040

The analysis of elemental composition of ambient dust can help not only evaluate the environmental and health effects due to the air pollution but also identify emission sources. However, the whole number of projects and studies on concentrations and elemental composition of ambient (especially fine) dust hardly concern these issues in Eastern Europe. Neither is the chemical (and elemental) composition of the submicron ambient dust in Poland well recognized. There is also a shortage of data from long-term and parallel studies of the elemental composition of separate dust fractions. In the heavily polluted areas, the elemental composition of atmospheric aerosol and the dependence of elemental composition of particles on their size can appear essential for analyzing the toxicity of dust and its environmental effects. This study presents the results of determination and comparison of the elemental composition of four fractions of ambient dust in Zabrze (Poland), an urban area typical of the exposure of the Upper-Silesian Agglomeration population to the polluted air. The samples of the four dust fractions (fine: ≤1 µm – PM1, 1–2.5 µm – PM1-2.5, coarse: 2.5–10 µm – PM2.5-10, and 10–40 µm – PM10-40,) were collected during eight months (January–August 2009) with the use of a DEKATI-PM10 cascade impactor. All the dust samples (204 samples) were analyzed using a PANalytical Epsilon 5 spectrometer (EDXRF – energy dispersive X-Ray fluorescence spectroscopy). The minimum, maximum and average concentrations, for winter (January–April, heating season) and summer (May–August, non-heating season), of 38 elements from each of the four examined dust fractions were calculated. The influence of anthropogenic sources on the ambient concentrations of elements from each dust fraction was determined by analyzing the enrichment factors (EF). The strength of linear relationships (Pearson’s linear correlation coefficients) between each pair of elements was determined separately for fine and coarse dust. The highest ambient concentrations were assumed by two nonmetals – sulfur and chlorine; their concentrations were significantly lower in summer than in winter. Both sulfur and chlorine were mainly bound onto the finest particles. Their share in the coarse dust, even in summer, was small. They came from anthropogenic sources. Ambient, typical crustal, Si, Al, Fe, Mg, K, Ca, Ti, Sr, Rb in Zabrze came from natural sources regardless of the fraction they were bound to. Small seasonal variations in ambient concentrations of these elements or some of the concentrations higher in summer than in winter confirmed the fact. A significant portion of the mass of the crustal elements, especially of Al, Si and Fe, was concentrated in the coarse fractions. However, the mass distribution among the dust fractions indicates some of them (K, Ca, Mg, Rb, Sr) as coming partly from anthropogenic sources. It particularly concerns their part bound to fine dust in winter. The mass contribution of crustal matter to ambient dust was about 6.8 in winter and 9.7% in summer; the contribution to PM1 was half of it. Almost all remaining 27 elements (except for Mn, Zn, Ge, Sb, La) had the ambient concentrations not greater than 100 ng m-3, usually higher in winter. The average mass shares of each of these 27 elements in PM1, PM1-2.5, PM2.5-10, and PM10-40, were different and depended on the season of a year. Co, Cu, Zn, Pb and As were cumulated mostly in fine dust, while V, Mn, Co, Cr, Ni, Ag, Cd and Ba in coarse dust. The former, in fine dust, were assumed to be rather of anthropogenic origin and closely associated with combustion. The later originated partly from combustion (especially in winter) but their greater part was secondary and came from road dust. The largest contributors to the mass of the elements in fine dust in Zabrze are domestic furnaces and car engines, i.e. combustion of fossil fuels, biomass, and waste. The possible effect of industrial sources was also identified. The elemental composition of coarse dust is due to re-suspension of soil and road dust, and to a lesser extent, to municipal emission.

Real distribution of the chemical elements in austenite and ferrite of 2205 duplex steel

Sozańska M.

Inżynieria Materiałowa

2004

R. XXV, nr 3

190-192

The microstructure of the duplex 2205 steel is an austeno-ferritic one. The average chemical composition of the steel does not reflect the real distribution of the chemical elements in individual phases, austenite and ferrite. Thus, for steel of a duplex type, an distribution coefficient x = x(alpha) / x(gamma) is often determined alpha and gamma phases. To this end, an X-ray analysis is used. Such determined coefficients of chemical elements distribution in the investigated duplex steel (quenching temperature 1050°C) amounted to: 1.21 Cr, 0.66Ni, 0.80 Mn, 1.64Mo. It turned out that the coefficients of elements distribution are almost identical for both initial state and after heat treatment state: austenitizing at 1050°C for 1 hour and quenching from a temperature of 1050°C, cooling in water.

Mikrostruktura stali duplex 2205 jest austenityczno-ferrytycza Średni skład chemiczny stali nie oddaje rzeczywistego rozkładu pierwiastków w poszczególnych fazach, austenicie i ferrycie. Stąd często dla stali typu duplex wyznacza się współczynnik rozdzału pierwiastków x = x(alfa) / x(gamma) pomiędzy fazy a i y. Wykorzystuje się w tym celu mikroanalizę rentgenowską. Wyznaczony współczynnik rozdziału pierwiastków w badanej stali duplex 2205 w stanie wyjściowym (po hartowaniu w 1050°C) wynosił: 1.21 Cr, 0.66Ni, 0.80 Mn, 1.64Mo. Prawie identyczne wyniki współczynnika rozdziału pierwiastków dla stali duplex otrzymano również po następującej obróbce cieplnej: austenityzacja w 1050°C podczas 1 godziny, następnie hartowanie w wodzie.

Wykorzystanie plazmy w procesach nanoszenia gradientowych warstw wierzchnich

Chmielewski M., Barlak M., Mikoś M.

Przegląd Spawalnictwa

2000

R. 72, nr 6

15-18

Przedstawiono wyniki badań kompozytowych warstw wierzchnich o budowie gradientowej natryskiwanych plazmowo na metalowym podłożu. Celem badań było uzyskanie warstwy o większej twardości oraz o wyższej odporności na zużycie w stosunku do podłoża. Otrzymane materiały gradientowe poddano szczegółowym badaniom m.in.: mikrotwardości, metalograficznym oraz liniowej i powierzchniowej analizie rozkładu pierwiastków.

Results of examining composite superficial layers of a gradient structure plasma sprayed on a metal base. The examinations tended towards getting a layer of a higher hardness and wear resistance relative to the base. The gradient materials obtained were subjected to detailed examinations, viz, metallography, microhardness tests, linear and surface analysis of chemical elements distribution.