Surface Functionality Features of Nanosized Silica Obtained by Electron Beam Evaporation at Ambient Pressure

A series of nanosized silica powders with different specific surface values are synthesized by electron beam evaporation in air at ambient pressure. The obtained silica samples are featured with relatively low apparent density and high content of oxygen and hydroxyl groups on the surface making these materials promising for specific applications

Analysis and Alternate Selection of Nanopowder Modifiers to Improve a Special Protective Coating System

This paper presents a practical approach for rational choice of silica nanopowders as modifiers to control and improve the performance of protective coating systems operating in harsh environmental conditions. The approach is based on the multiparameter analysis of nanoparticle reactivity of similar silica synthesized by using chemical and physical methods. The analysis indicates distinct adsorption centers due to the differences in the particles formation; the features of the formation and adsorption mechanisms lead to higher diffusion capacity of the nanoparticles, synthesized by physical methods, into a paint material and finally result in stronger chemical bonds between the system elements. The approach allows reducing the consumption of paint materials by 30% or more, at least 2-3 times increasing of the coating adhesion and hence the system life. Validity of the approach is illustrated through the data obtained from comparative modeling, factory testing, and practical use of modified systems

Preparation of copper and silicon/copper powders by a gas evaporation-condensation method

Pure and silicon-coated metal copper nano to submicron-sized powders were prepared by gas evaporation and condensation. This powder was synthesized by using an industrial electron accelerator, ELV-6, with Ar as the carrier gas. Vapour from the liquefied metal surface was transferred to the cold zone by the carrier gas and precipitated as spherical Cu metal and Si/Cu composite powders. The mean diameter of the resulting powder was 100–200 nm