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| Titel |
Grain-size dependence of the magnetic properties of street dusts from Warsaw, Poland |
| VerfasserIn |
Sylwia Dytłow, Aldo Winkler, Leonardo Sagnotti |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250111762
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| Publikation (Nr.) |
 EGU/EGU2015-11904.pdf |
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| Zusammenfassung |
| In recent years, in connection with a substantial development of transportation in urban areas,
vehicular traffic increased its importance as source of pollution and consequent cause of
health problems in urban environments. In fact, it is well established that the concentration
and size of pollution related particulate matter (PM) are important factors affecting human
health.
The aim of this study is to identify the variations of the magnetic properties and of
the chemical composition of different granulometric fractions from street dusts
collected at four locations in Warsaw: the city center, a suburb, a tramline and a big
crossroad.
Dust samples were mechanically sieved and classified using the laboratory shaker with a
standard sieve set (0.5 mm, 0.25 mm, 0.1 mm and 0.071 mm).
Data show a distribution of magnetic susceptibility (Ï) in the wide range of 80–370 x
10-8 m3kg-1. Comparison of magnetic parameters shows that the street dust contains
the pollution characteristics for air and soil. The samples were characterized by
uniform magnetic mineralogy, typical for fine-grained magnetite, in a grain size range
between pseudo-single-domain and fine multi-domain, with a small contribution
from ultrafine superparamagnetic particles (~2-3.5 %). The street dust contains,
as usual for the urban areas, spherical magnetic particles produced by fossil fuel
combustion processes and mixture of irregular angular iron-oxides grains containing other
elements.
The magnetic susceptibility and hysteresis properties of the dusts have been analyzed in
detail; the temperature variation of the saturation of remanent magnetization and of the
magnetic susceptibility revealed that the main magnetic mineral, for all the fractions, is
almost stoichiometric magnetite, with the finest fractions (d=0.1 mm, 0.071 mm and d |
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