| Autor: |
Thomas, Gareth E., Bass, Stephen F., Grainger, Roy G., Lambert, Alyn |
| Zdroj: |
Applied Optics; March 2005, Vol. 44 Issue: 7 p1332-1341, 10p |
| Abstrakt: |
A new method for the retrieval of the spectral refractive indices of micrometer-sized particles from infrared aerosol extinction spectra has been developed. With this method we use a classical damped harmonic-oscillator model of molecular absorption in conjunction with Mie scattering to model extinction spectra, which we then fit to the measurements using a numerical optimal estimation algorithm. The main advantage of this method over the more traditional Kramers–Kronig approach is that it allows the full complex refractive-index spectra, along with the parameters of the particle size distribution, to be retrieved from a single extinction spectrum. The retrieval scheme has been extensively characterized and has been found to provide refractive indices with a maximum uncertainty of ~10% (with a minimum of ~0.1%). Comparison of refractive indices calculated from measurements of a ternary solution of HNO_3, H_2SO_4, and H_2O with those published in J. Phys. Chem. A104, 783 ( 2000) show similar differences as found by other authors. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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