Results 261 to 270 of about 9,859,885 (301)

Pan-Arctic trends of aerosol particle number concentrations in different size fractions

2022
<p><strong>Introduction</strong></p><p>The Arctic region is particularly sensitive to global climate change, experiencing warming at twice the rate of the global average. Changes within and outside of the Arctic (e.g., meteorology, atmospheric transport, and precipitation patterns ...
Jakob Boyd Pernov, Peter Tunved, Sangeeta Sharma, Eija Asmi, Niku Kivekäs, Julia Schmale, Johan Ström, Hans-Christen Hansson, Henrik Skov, Andreas Massling   +9 more
openaire   +1 more source

Meteorological dependence of size-fractionated number concentrations of urban aerosol particles

Atmospheric Environment, 2006
Abstract We utilized a long-term data set of aerosol particle number size distributions (8–400 nm) in the urban background air of Helsinki during 1998–2000.
Tareq Hussein, Ari Karppinen, Jaakko Kukkonen, Jari Härkönen, Pasi P. Aalto, Kaarle Hämeri, Veli-Matti Kerminen, Markku Kulmala   +7 more
openaire   +1 more source

Statistical Analysis of Soot Volume Fractions, Particle Number Densities and Particle Radii in a Turbulent Diffusion Flame

Combustion Science and Technology, 1999
A recently developed two-dimensional optical technique has been applied for measuring two-dimensional maps of soot volume fractions, particle number densities and mean particle radii in a turbulent acetylene-air diffusion flame. The technique is based on the simultaneous detection of Rayleigh-Scattering and Laser-Induced Incandescence (LII) in ...
Geitlinger, Hilmar, Streibel, Thorsten, Suntz, Rainer, Bockhorn, Henning   +3 more
openaire   +1 more source

Particle-number estimation with special emphasis on the disector and fractionator

Proceedings, annual meeting, Electron Microscopy Society of America, 1993
This abstract deals with how to stereologically estimate the number of particles in sections without making any assumptions about the size or shape of the particles. The usual term for this kind of particle estimation is design-based because by designing the study adequately any size or shape-assumptions are avoided in contrast to the obsolete model ...
openaire   +1 more source

Number concentration, size distribution and fine particle fraction of tropospheric and stratospheric aerosols

China Particuology, 2003
Abstract Aerosol observations were carried out at Xianghe Scientific Balloon Base (39.45°N, 117°E) using a stratospheric balloon. The particle number concentrations of the tropospheric and stratospheric aerosols were directly explored. The vertical distributions of the number concentration, number-size (that is, particle number versus particle size ...
Li Xu, Guangyu Shi, Li Zhang, Jun Zhou, Yasunobu Iwasaka   +4 more
openaire   +1 more source

Quality control of semi-continuous mobility size-fractionated particle number concentration data

Atmospheric Environment, 2004
Abstract Fine and ultrafine particles have been postulated to play an important role in the association between ambient particulate matters and adverse health effects. As part of the EPA Supersite Program, the Southern California Particle Center & Supersite has conducted a series of monitoring campaigns that contribute to a better understanding of ...
Rong Chun Yu, Hee Wen Teh, Peter A. Jaques, Constantinos Sioutas, John R. Froines   +4 more
openaire   +2 more sources

Influence of Rayleigh number and solid volume fraction in particle-dispersed natural convection

International Journal of Heat and Mass Transfer, 2018
Abstract To study the heat transfer in a natural convection under dense particulate condition with finite-size spherical particles of uniform diameter, a direct numerical simulation is conducted. For calculating the momentum-interaction between the particle and fluid, our original immersed solid method is applied.
Jingchen Gu, Shintaro Takeuchi, Takeo Kajishima   +2 more
openaire   +1 more source

Determination of number-based size distribution of silica particles using centrifugal field-flow fractionation

Journal of Chromatography A, 2019
Determination of the number-based size distribution of silica particles using the centrifugal field-flow fractionation (CF3) method was investigated. Since the accurate determination of the number-based size distribution of materials is essential in the fields of nanotechnology and biotechnology, the establishment of a robust evaluation method is ...
Haruhisa Kato, Ayako Nakamura, Hidekuni Banno   +2 more
openaire   +2 more sources

Experimental study of local solid volume fraction fluctuations in a liquid fluidized bed: Particles with a wide range of stokes numbers

International Journal of Multiphase Flow, 2021
Abstract In this study, the solid volume fraction fluctuations of different solid particles in a fluidized bed were measured using an Electrical Impedance Tomography system, which provides local fluctuation values. A wide range of particle Stokes numbers ( 122 ≤ S t t ≤ 3809 ) was tested by selecting specific particle sizes and ...
Maedeh Marefatallah, David Breakey, R. Sean Sanders   +2 more
openaire   +1 more source

The number fraction of iron-containing particles affects OH, HO2 and H2O2 budgets in the atmospheric aqueous phase

2022
Abstract. Reactive oxygen species (ROS), such as OH, HO2 and H2O2, affect the oxidation capacity of the atmosphere and cause adverse health effects of particulate matter. The role of transition metal ions (TMIs) in impacting the ROS concentrations and conversions in the atmospheric aqueous phase has been recognized for a long time.
Khaled, Amina, Zhang, Minghui, Ervens, Barbara   +2 more
openaire   +2 more sources