The fine particles serving as cloud condensation nuclei in pristine Amazonian rainforest air consist mostly of secondary organic aerosol. Their origin is enigmatic, however, because new particle formation in the atmosphere is not observed. Here, we show that the growth of organic aerosol particles can be initiated by potassium-salt-rich particles emitted by biota in the rainforest. These partic...

Original scientific paper High-velocity water jet expanded into many fields of human activity due to its unique properties. Besides already traditional technological processes it begins to find its way also to the comminution of mineral particles. The paper analyzes the possibility of particle comminution using an abrasive mixing head used to generate high-velocity abrasive water jet and an imp...

Surfactant-free emulsion polymerization involving a nonionic, and hence uncharged initiator presents a new approach towards environmentally friendly procedures to synthesize latex particles. Under optimal solvent conditions, notably pH and ionic strength, the latex particles are stabilized by the natural development of ionic charge at the surface of the particles. We emphasize that the present ...

The size and thickness of organic aerosol particles collected by impaction in five field campaigns were compared to those of laboratory-generated secondary organic aerosols (SOA). Scanning transmission X-raymicroscopy was used tomeasure the total carbon absorbance (TCA) by individual particles as a function of their projection areas on the substrate. Particles with higher viscosity/surface tens...

The role of soot and volatile aerosol in controlling ice particle formation in cirrus clouds is of global importance for climate. In particular, contrail studies may help to better understand the role of various aerosols in ice formation. Recent results suggest that contrails may contribute a large share to the climate impact of aviation. Hence, better knowledge on contrails is needed for devel...

In this paper, we contribute new data on the dielectric dispersion of suspensions of two kinds of spheroidal hematite particles (R-Fe2O3). One of the samples consisted of nearly spherical particles, and the other included almost spindle-like particles. We intended to demonstrate the unique potential applications of dielectric dispersion measurements on the characterization of the electrical dou...

Carbonaceous aerosols are responsible for large uncertainties in climate models, degraded visibility, and adverse health effects. The Carbonaceous Aerosols and Radiative Effects Study (CARES) was designed to study carbonaceous aerosols in the natural environment of the Central Valley, California, and learn more about their atmospheric formation and aging. This paper presents results from spectr...

Lipemic plasma from normal and hyperlipemic patients has been fractionated on columns of 3% (w/v) aqueous polyvinylpyrrolidone (PVP) and the lipid composition of the separated fat particles (S(f) > 400) measured. Plasma from patients with carbohydrate-induced lipemia on fat-free diets contained particles with a greater percentage of cholesterol and phospholipid than either normal primary partic...

The interconversion of atmospheric organic particles among solid, semisolid, and liquid phases is of keen current scientific interest, especially for particles of secondary organic material (SOM). Herein, the influence of phase on ammonia uptake and subsequent particle-phase reactions was investigated for aerosol particles of adipic acid and α-pinene ozonolysis SOM. The nitrogen content of the ...

The effect of secondary steelmaking processes such as desulphurization, removal of inclusions and vacuum degassing followed by hot forging and hardening heat treatment on the microstructure and mechanical properties of a hot-work w500 tool steel have been studied in details. In order to follow the progress of secondary steel making, the content of impurity elements such as S, P, O, H and N were...