12 research outputs found
Chemical characterization of laboratory-generated tar ball particles
The chemical properties of laboratory-generated
tar ball (Lab-TB) particles produced from dry distillate
(wood tars) of three different wood species in the laboratory
were investigated by analytical techniques that had
never been used before for their characterization. The elemental
compositions of laboratory-generated tar balls (Lab-
TBs) from three tree species were very similar to one another
and to those characteristic of atmospheric tar balls (TBs) collected
from the savanna fire during the SAFARI 2000 sampling
campaign. The O=C and H= C molar ratios of the generated
Lab-TBs were at the upper limit characteristic of soot
particles. The Fourier transform infrared spectroscopy (FTIR)
spectra of the generated Lab-TBs were very similar to
one another as well and also showed some similarity with
those of atmospheric humic-like substances (HULIS). The
FT-IR measurements indicated that Lab-TBs have a higher
proportion of aromatic structure than HULIS and the oxygen
atoms of Lab-TBs are mainly found in hydroxyl and keto
functional groups. Whereas Raman activity was detected in
the starting materials of the Lab-TBs (wood tars) in the
range of 1000–1800 c