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 H2O 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 µs to 100 µs after particle formation with growth rates of 0.2 to 0.02 nm µs-1. The peak H2O nucleation rates lie between 1017 and 1018 cm-3 s-1.

Department(s)

Physics

Sponsor(s)

American Chemical Society
National Science Foundation (U.S.)
Petroleum Research Fund
United States. Department of Energy

Keywords and Phrases

Nanodroplets; Small-angle x-ray scattering; Supersonic nozzles; Water

International Standard Serial Number (ISSN)

1463-9076

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2007 Royal Society of Chemistry, All rights reserved.

Publication Date

01 Jan 2007

Link to Full Text

Share

 
COinS