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Title: Small angle x-ray scattering measurements probe water nanodroplet evolution under highly non-equilibrium conditions.

Abstract

Our in situ small angle X-ray scattering (SAXS) measurements yield an unprecedented and detailed view of rapidly evolving H{sub 2}O nanodroplets formed in supersonic nozzles. The SAXS experiments produce spectra in a few seconds that are comparable to small angle neutron scattering (SANS) spectra requiring several hours of integration time and the use of deuterated compounds. These measurements now make it possible to quantitatively determine the maximum nucleation and growth rates of small droplets formed under conditions that are far from equilibrium. Particle growth is directly followed from about 10 {micro}s to 100 {micro}s after particle formation with growth rates of 0.2 to 0.02 nm {micro}s{sup -1}. The peak H{sub 2}O nucleation rates lie between 10{sup 17} and 10{sup 18} cm{sup -3} s{sup -1}.

Authors:
; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC); National Science Foundation (NSF); Donors of Petroleum Research Fund
OSTI Identifier:
939328
Report Number(s):
ANL/XSD/JA-60197
Journal ID: ISSN 1463-9076; TRN: US0806753
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Phys. Chem. Chem. Phys.; Journal Volume: 9; Journal Issue: 39 ; 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; NEUTRONS; NOZZLES; NUCLEATION; PROBES; SCATTERING; SPECTRA; WATER

Citation Formats

Wyslouzil, B. E., Wilemski, G., Strey, R., Seifert, S., Winans, R. E., X-Ray Science Division, Ohio State Univ., Univ. of Missouri, and Inst. fur Physikalische Chemie. Small angle x-ray scattering measurements probe water nanodroplet evolution under highly non-equilibrium conditions.. United States: N. p., 2007. Web. doi:10.1039/b709363b.
Wyslouzil, B. E., Wilemski, G., Strey, R., Seifert, S., Winans, R. E., X-Ray Science Division, Ohio State Univ., Univ. of Missouri, & Inst. fur Physikalische Chemie. Small angle x-ray scattering measurements probe water nanodroplet evolution under highly non-equilibrium conditions.. United States. doi:10.1039/b709363b.
Wyslouzil, B. E., Wilemski, G., Strey, R., Seifert, S., Winans, R. E., X-Ray Science Division, Ohio State Univ., Univ. of Missouri, and Inst. fur Physikalische Chemie. Mon . "Small angle x-ray scattering measurements probe water nanodroplet evolution under highly non-equilibrium conditions.". United States. doi:10.1039/b709363b.
@article{osti_939328,
title = {Small angle x-ray scattering measurements probe water nanodroplet evolution under highly non-equilibrium conditions.},
author = {Wyslouzil, B. E. and Wilemski, G. and Strey, R. and Seifert, S. and Winans, R. E. and X-Ray Science Division and Ohio State Univ. and Univ. of Missouri and Inst. fur Physikalische Chemie},
abstractNote = {Our in situ small angle X-ray scattering (SAXS) measurements yield an unprecedented and detailed view of rapidly evolving H{sub 2}O nanodroplets formed in supersonic nozzles. The SAXS experiments produce spectra in a few seconds that are comparable to small angle neutron scattering (SANS) spectra requiring several hours of integration time and the use of deuterated compounds. These measurements now make it possible to quantitatively determine the maximum nucleation and growth rates of small droplets formed under conditions that are far from equilibrium. Particle growth is directly followed from about 10 {micro}s to 100 {micro}s after particle formation with growth rates of 0.2 to 0.02 nm {micro}s{sup -1}. The peak H{sub 2}O nucleation rates lie between 10{sup 17} and 10{sup 18} cm{sup -3} s{sup -1}.},
doi = {10.1039/b709363b},
journal = {Phys. Chem. Chem. Phys.},
number = 39 ; 2007,
volume = 9,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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