Retrieving aerosol optical properties from moments of the particle size distribution

1997 ◽  
Vol 24 (6) ◽  
pp. 651-654 ◽  
Author(s):  
G. K. Yue ◽  
J. Lu ◽  
V. A. Mohnen ◽  
P.-H. Wang ◽  
V. K. Saxena ◽  
...  
Keyword(s):  
Particle Size ◽  
Optical Properties ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Aerosol Optical Properties

scholarly journals Impact of particle size, refractive index, and shape on the determination of the particle scattering coefficient – an optical closure study evaluating different nephelometer angular truncation and illumination corrections

2021 ◽  
Author(s):  
Marilena Teri ◽  
Thomas Müller ◽  
Josef Gasteiger ◽  
Sara Valentini ◽  
Helmuth Horvath ◽  
...  
Keyword(s):  
Particle Size ◽  
Refractive Index ◽  
Optical Properties ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Mineral Dust ◽  
Scattering Coefficient ◽  
Particle Scattering ◽  
Aerosol Optical Properties ◽  
Angular Correction

Abstract. Aerosol particles in the atmosphere interact with solar radiation through scattering and absorption. Accurate aerosol optical properties are needed to reduce the uncertainties of climate predictions. The aerosol optical properties can be obtained via optical modeling based on the measured particle size distribution. This approach requires knowledge or assumptions on the particle refractive index and shape. Meanwhile, integrating nephelometry provides information on the aerosol scattering properties directly. However, their measurements are affected by angular non-idealities, and their data need to be corrected for angular truncation and illumination to provide the particle scattering coefficient. We performed an extensive closure study, including a laboratory and a simulated experiment, aiming to compare different nephelometer angular truncation and illumination corrections (further referred to as "angular corrections"). We focused on coarse mode irregularly shaped aerosols, such as mineral dust, a worldwide abundant aerosol component. The angular correction of irregular particles is found to be only ~2 % higher than the angular correction of volume equivalent spheres. If the angular correction is calculated with Mie theory, the particle size distribution is needed. Our calculations show that if the particle size distribution is retrieved from optical particle spectrometer measurements and the irregular shape effect is not considered, the angular correction can be overestimated by about 5 % and up to 22 %. For mineral dust, the traditional angular correction based on the wavelength dependency of the scattering coefficient seems more accurate. We propose a guideline to establish the most appropriate angular correction depending on the aerosol type and the investigated size range.

scholarly journals Influence of Particle Size Distribution on the Optical Properties of Fine-Dispersed Suspensions

2022 ◽  
Vol 18 (1) ◽  
pp. 1-14
Author(s):  
Dmitrii Kuzmenkov ◽  
Pavel Struchalin ◽  
Yulia Litvintsova ◽  
Maksim Delov ◽  
Vladimir Skrytnyy ◽  
...  
Keyword(s):  
Particle Size ◽  
Optical Properties ◽  
Particle Size Distribution ◽  
Size Distribution

scholarly journals Characteristics of Aerosol during a Severe Haze-Fog Episode in the Yangtze River Delta: Particle Size Distribution, Chemical Composition, and Optical Properties

Atmosphere ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 56 ◽  
Author(s):  
Ankang Liu ◽  
Honglei Wang ◽  
Yi Cui ◽  
Lijuan Shen ◽  
Yan Yin ◽  
...  
Keyword(s):  
Particle Size ◽  
Optical Properties ◽  
Chemical Composition ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Water Soluble ◽  
Air Masses ◽  
Soluble Ions ◽  
Wide Range ◽  
Water Soluble Ions

Particle size distribution, water soluble ions, and black carbon (BC) concentration in a long-term haze-fog episode were measured using a wide-range particle spectrometer (WPS), a monitor for aerosols and gases (MARGA), and an aethalometer (AE33) in Nanjing from 16 to 27 November, 2018. The observation included five processes of clean, mist, mix, haze, and fog. Combined with meteorological elements, the HYSPLIT model, and the IMPROVE model, we analyzed the particle size distribution, chemical composition, and optical properties of aerosols in different processes. The particle number size distribution (PNSD) in five processes differed: It was bimodal in mist and fog and unimodal in clean, mix, and haze. The particle surface area size distribution (PSSD) in different processes showed a bimodal distribution, and the second peak of the mix and fog processes shifted to a larger particle size at 480 nm. The dominant air masses in five processes differed and primarily originated in the northeast direction in the clean process and the southeast direction in the haze process. In the mist, mix, and fog processes local air masses dominated. NO3− was the primary component of water soluble ions, with the lowest proportion of 45.6% in the clean process and the highest proportion of 53.0% in the mix process. The ratio of NH4+ in the different processes was stable at approximately 23%. The ratio of SO42− in the clean process was 26.2%, and the ratio of other processes was approximately 20%. The average concentration of BC in the fog processes was 10,119 ng·m−3, which was 3.55, 1.80, 1.60, and 1.46 times that in the processes of clean, mist, mix, and haze, respectively. In the different processes, BC was primarily based on liquid fuel combustion. NO3−, SO42−, and BC were the main contributors to the atmospheric extinction coefficient and contributed more than 90% in different processes. NO3− contributed 398.43 Mm−1 in the mix process, and SO42− and BC contributed 167.90 Mm−1 and 101.19 Mm−1, respectively, during the fog process.

Determination of particle size distribution of water-soluble CdTe quantum dots by optical spectroscopy

RSC Advances ◽  
2014 ◽  
Vol 4 (68) ◽  
pp. 36024-36030 ◽  
Author(s):  
J. C. L. Sousa ◽  
M. G. Vivas ◽  
J. L. Ferrari ◽  
C. R. Mendonca ◽  
M. A. Schiavon
Keyword(s):  
Quantum Dots ◽  
Particle Size ◽  
Optical Properties ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Water Soluble ◽  
Cdte Quantum Dots ◽  
One Pot ◽  
The One

In the present study, we report the synthesis of glutathione (GSH) capped CdTe quantum dots (QDs) using the one-pot approach as well as their optical properties.

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