Total and polarized radiances provided by the Polarization and Directionality of Earth Reflectances (POLDER) satellite sensor are used to retrieve the microphysical and optical properties of the volcanic plume observed during the Eyjafjallajökull volcano eruption in 2010, over cloud-free and cloudy ocean scenes. We selected two plume conditions, fresh aerosols near the sources (three cases) and...

A Mie backscattering model for spherical particles with off-center inclusion has been developed and tested. The program is capable of dealing with size parameter values up to approximately 1000, thus allowing one to simulate the optical behavior of a large variety of atmospheric aerosols, as well as cloud and precipitation particles. On the basis of this model, we simulated the optical properti...

Atmospheric aerosols, an important component of the atmosphere, are derived from a variety of sources (natural and anthropogenic) and comprise of wide-range of particles having different chemical composition, size (0.001 μm to 100 μm), shape and optical properties. They are mainly confined to the lower troposphere wherein intense vertical and horizontal mixing takes place. As a consequence, lar...

The phase transitions and hygroscopic growth of two humic acid aerosols (Aldrich sodium salt and Leonardite Standard (IHSS)) and their mixtures with ammonium sulphate have been investigated using a combination of two techniques, Fourier transform infra-red (FTIR) spectroscopy and tandem differential mobility analysis (TDMA). A growth factor of 1.16 at 85% relative humidity (RH ) was found for t...

Aerosols could be injected into the upper atmosphere to engineer the climate by scattering incident sunlight so as to produce a cooling tendency that may mitigate the risks posed by the accumulation of greenhouse gases. Analysis of climate engineering has focused on sulfate aerosols. Here I examine the possibility that engineered nanoparticles could exploit photophoretic forces, enabling more c...

INTRODUCTION Radioactive nuclides are formed through nuclear reactions in the air of accelerator tunnels during machine operation. Especially, in high-energy accelerator facilities, various radionuclides are produced from the air through many kinds of nuclear reactions, such as nuclear spallation reactions. In addition, nonradioactive aerosols are abundantly generated in the air due to high rad...

The formation characteristics of aerosol particles from pulverized coal pyrolysis in high temperatures are studied experimentally. By conducting a drop-tube furnace, fuel pyrolysis processes in industrial furnaces are simulated in which three different reaction temperatures of 1000, 1200, and 1400 degrees C are considered. Experimental observations indicate that when the reaction temperature is...

This work aims at presenting a nanoparticle generation non-transportable facility in aerosol phase called “CAIMAN” (acronym for Characterization of Instruments Measuring Aerosols of Nanoparticles) and its performances. This facility delivers primary nanoaerosols from electrodes made of C, Al, Cu (and mixtures containing Be), Ag, Constantane (a mixture of Cu-55wt% and Ni-45wt%) particles at know...

Neutralization of Acidic Sulfur Species by Calcite in Mineral Aerosols Collected in China and Japan Studied by Ca K-Edge X-Ray Absorption Near-Edge Structure Spectroscopy X-ray absorption near-edge structure studies at the calcium K-edge have been used to show that acidic sulfur species in the atmosphere (e.g., H2SO4), mainly released by human activities, can be neutralized by the calcite prese...