Measurements of the structures of nanoparticles in flames by in situ detection of scattered x-ray radiation
Publikation/Tidskrift/Serie: JOURNAL OF APPLIED PHYSICS
Förlag: American Institute of Physics
The angular pattern of scattered synchrotron x-ray radiation has been used to measure the composition of molecules and nanometer-sized particles in flames. The measured patterns were compared with patterns obtained from calculations for different species compositions. After ensuring that the calculations could reproduce the experiments for air and for ethylene flames under two different combustion conditions flames under special particle producing conditions were studied. In one case, the patterns showed a strong presence of spherical or fullerenelike structures with very little presence of graphitelike particles and little soot production on a cooling plate. In the other case, under soot producing conditions, the scattering showed a clear presence of nanometer-sized graphite particles. The results show that high concentrations of particles with the size around 1 nm can be produced in flames. These particles either remain free or condense into larger particles, depending on the combustion conditions. This technique opens up for experimental studies of molecular and particle dynamics in combustion processes and other processes where nucleation and structural transformations of particles occur.
- Physics and Astronomy
- ISSN: 0021-8979