Derivation of the Density and Refractive Index of Organic Matter and Elemental Carbon from Closure between Physical and Chemical Aerosol Properties
Schmid, Otmar ; Chand, Duli ; Karg, Erwin ; Guyon, Pascal ; Frank, Göran LU
; Swietlicki, Erik
LU
and Andreae, Meinrat O.
(2009)
In Environmental Science & Technology
43(4).
p.1166-1172
- Abstract
- Information on the density (p) and refractive index m(=n-ik) of elemental carbon (ECa) and organic matter (OMa), the main carbon components of atmospheric aerosols, has frequently been obtained from closure calculations between physical and chemical aerosol properties. However, this approach has suffered from large uncertainties since there were more unknown (or poorly known) parameters than defining equations. In this study, we propose a method that avoids this ambiguity mainly by considering both optical and mass closure and by expressing the three ECa parameters (p(Eca), n(Eca), k(ECa)) by a single (unknown) parameter. This allows mathematically rigorous determination of p(Eca), m(Eca), p(OMa) and m(OMa) from standard physico-chemical... (More)
- Information on the density (p) and refractive index m(=n-ik) of elemental carbon (ECa) and organic matter (OMa), the main carbon components of atmospheric aerosols, has frequently been obtained from closure calculations between physical and chemical aerosol properties. However, this approach has suffered from large uncertainties since there were more unknown (or poorly known) parameters than defining equations. In this study, we propose a method that avoids this ambiguity mainly by considering both optical and mass closure and by expressing the three ECa parameters (p(Eca), n(Eca), k(ECa)) by a single (unknown) parameter. This allows mathematically rigorous determination of p(Eca), m(Eca), p(OMa) and m(OMa) from standard physico-chemical aerosol data and rigorous error analysis. The results are unambiguous and self-consistent, i.e., there is no difference between the chemically and physically derived p and m values of the atmospheric aerosol. Application of this method to our previously published data on biomass burning particles from Amazonia yields p(Eca) = 1.8(+/- 0.2) g/cm(3), m(ECa) = 1.9(+/- 0.1)-i0.20(-0.04/+0.02), p(OMa) = 1.39(+/- 0.13) g/cm(3) and m(OMa)=1.46(+/- 0.02), where the 1 sigma uncertainty limits given in parenthesis are based on the principles of error propagation. The relatively low imaginary part of mEca indicates the presence of only partially graphitized elemental carbon, which is consistent with biomass burning aerosol dominated bysmoldering combustion conditions. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1375026
- author
- Schmid, Otmar
; Chand, Duli
; Karg, Erwin
; Guyon, Pascal
; Frank, Göran
LU
; Swietlicki, Erik
LU
and Andreae, Meinrat O.
- organization
- publishing date
- 2009
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Environmental Science & Technology
- volume
- 43
- issue
- 4
- pages
- 1166 - 1172
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- wos:000263298600035
- scopus:64349096429
- ISSN
- 1520-5851
- DOI
- 10.1021/es800570p
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Nuclear Physics (Faculty of Technology) (011013007)
- id
- c29e726e-99c8-4bad-8170-6f44689640e8 (old id 1375026)
- date added to LUP
- 2016-04-01 14:35:36
- date last changed
- 2022-05-27 02:24:18
@article{c29e726e-99c8-4bad-8170-6f44689640e8,
abstract = {{Information on the density (p) and refractive index m(=n-ik) of elemental carbon (ECa) and organic matter (OMa), the main carbon components of atmospheric aerosols, has frequently been obtained from closure calculations between physical and chemical aerosol properties. However, this approach has suffered from large uncertainties since there were more unknown (or poorly known) parameters than defining equations. In this study, we propose a method that avoids this ambiguity mainly by considering both optical and mass closure and by expressing the three ECa parameters (p(Eca), n(Eca), k(ECa)) by a single (unknown) parameter. This allows mathematically rigorous determination of p(Eca), m(Eca), p(OMa) and m(OMa) from standard physico-chemical aerosol data and rigorous error analysis. The results are unambiguous and self-consistent, i.e., there is no difference between the chemically and physically derived p and m values of the atmospheric aerosol. Application of this method to our previously published data on biomass burning particles from Amazonia yields p(Eca) = 1.8(+/- 0.2) g/cm(3), m(ECa) = 1.9(+/- 0.1)-i0.20(-0.04/+0.02), p(OMa) = 1.39(+/- 0.13) g/cm(3) and m(OMa)=1.46(+/- 0.02), where the 1 sigma uncertainty limits given in parenthesis are based on the principles of error propagation. The relatively low imaginary part of mEca indicates the presence of only partially graphitized elemental carbon, which is consistent with biomass burning aerosol dominated bysmoldering combustion conditions.}},
author = {{Schmid, Otmar and Chand, Duli and Karg, Erwin and Guyon, Pascal and Frank, Göran and Swietlicki, Erik and Andreae, Meinrat O.}},
issn = {{1520-5851}},
language = {{eng}},
number = {{4}},
pages = {{1166--1172}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Environmental Science & Technology}},
title = {{Derivation of the Density and Refractive Index of Organic Matter and Elemental Carbon from Closure between Physical and Chemical Aerosol Properties}},
url = {{http://dx.doi.org/10.1021/es800570p}},
doi = {{10.1021/es800570p}},
volume = {{43}},
year = {{2009}},
}