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Title: Particle formation from pulsed laser irradiation of soot aggregates studied with a scanning mobility particle sizer, a transmission electron microscope, and a scanning transmission x-ray microscope

Abstract

We investigated the physical and chemical changes induced in soot aggregates exposed to laser radiation using a scanning mobility particle sizer, a transmission electron microscope,and a scanning transmission x-ray microscope to perform near-edge x-ray absorption fine structure spectroscopy. Laser-induced nanoparticle production was observed at fluences above0.12 J/cm2 at532 nm and0.22 J/cm2 at1064 nm. Our results indicate that new particle formation proceeds via (1) vaporization of small carbon clusters by thermal or photolytic mechanisms, followed by homogeneous nucleation, (2) heterogeneous nucleation of vaporized carbon clusters onto material ablated from primary particles, or (3)both processes.

Authors:
; ; ; ; ;
Publication Date:
OSTI Identifier:
20929659
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Optics; Journal Volume: 46; Journal Issue: 6; Other Information: DOI: 10.1364/AO.46.000959; (c) 2007 Optical Society of America; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION SPECTROSCOPY; ATOMIC CLUSTERS; CARBON; EVAPORATION; FINE STRUCTURE; LASER RADIATION; LASERS; MICROSCOPES; NUCLEATION; OPTICAL MICROSCOPY; PARTICLE SIZE; PHOTOCHEMISTRY; SOOT; TRANSMISSION ELECTRON MICROSCOPY; X RADIATION; X-RAY SPECTROSCOPY

Citation Formats

Michelsen, Hope A., Tivanski, Alexei V., Gilles, Mary K., Poppel, Laura H. van, Dansson, Mark A., and Buseck, Peter R. Particle formation from pulsed laser irradiation of soot aggregates studied with a scanning mobility particle sizer, a transmission electron microscope, and a scanning transmission x-ray microscope. United States: N. p., 2007. Web. doi:10.1364/AO.46.000959.
Michelsen, Hope A., Tivanski, Alexei V., Gilles, Mary K., Poppel, Laura H. van, Dansson, Mark A., & Buseck, Peter R. Particle formation from pulsed laser irradiation of soot aggregates studied with a scanning mobility particle sizer, a transmission electron microscope, and a scanning transmission x-ray microscope. United States. doi:10.1364/AO.46.000959.
Michelsen, Hope A., Tivanski, Alexei V., Gilles, Mary K., Poppel, Laura H. van, Dansson, Mark A., and Buseck, Peter R. Tue . "Particle formation from pulsed laser irradiation of soot aggregates studied with a scanning mobility particle sizer, a transmission electron microscope, and a scanning transmission x-ray microscope". United States. doi:10.1364/AO.46.000959.
@article{osti_20929659,
title = {Particle formation from pulsed laser irradiation of soot aggregates studied with a scanning mobility particle sizer, a transmission electron microscope, and a scanning transmission x-ray microscope},
author = {Michelsen, Hope A. and Tivanski, Alexei V. and Gilles, Mary K. and Poppel, Laura H. van and Dansson, Mark A. and Buseck, Peter R},
abstractNote = {We investigated the physical and chemical changes induced in soot aggregates exposed to laser radiation using a scanning mobility particle sizer, a transmission electron microscope,and a scanning transmission x-ray microscope to perform near-edge x-ray absorption fine structure spectroscopy. Laser-induced nanoparticle production was observed at fluences above0.12 J/cm2 at532 nm and0.22 J/cm2 at1064 nm. Our results indicate that new particle formation proceeds via (1) vaporization of small carbon clusters by thermal or photolytic mechanisms, followed by homogeneous nucleation, (2) heterogeneous nucleation of vaporized carbon clusters onto material ablated from primary particles, or (3)both processes.},
doi = {10.1364/AO.46.000959},
journal = {Applied Optics},
number = 6,
volume = 46,
place = {United States},
year = {Tue Feb 20 00:00:00 EST 2007},
month = {Tue Feb 20 00:00:00 EST 2007}
}
  • We investigated the physical and chemical changes induced in soot aggregates exposed to laser radiation using a scanning mobility particle sizer, a transmission electron microscope, and a scanning transmission x-ray microscope to perform near-edge x-ray absorption fine structure spectroscopy. Laser-induced nanoparticle production was observed at fluences above 0.12 J/cm(2) at 532 nm and 0.22 J/cm(2) at 1064 nm. Our results indicate that new particle formation proceeds via (1) vaporization of small carbon clusters by thermal or photolytic mechanisms, followed by homogeneous nucleation, (2) heterogeneous nucleation of vaporized carbon clusters onto material ablated from primary particles, or (3) both processes.
  • Closed form analytical equations used to calculate the collection solid angle of six common geometries of solid-state X-ray detectors in scanning and scanning/transmission analytical electron microscopy are presented. Using these formulae one can make realistic comparisons of the merits of the different detector geometries in modern electron column instruments. This work updates earlier formulations and adds new detector configurations.
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