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Vacuum ultraviolet(VUV) irradiation (wavelength 147 nm) of siloxane polymers in the presence of air was studied using ATR FTIR and XPS spectroscopy. The ATR FTIR study revealed the formation of CO and OH groups in the surface layer depending on irradiation time and air pressure. The concentrations of CO and OH groups level off with the increase of irradiation time and pass through the maximum value with the increase of pressure in the range of 0.1-100 torr. The XPS study of irradiated polysiloxane films demonstrated that intermolecular crosslinking via oxygen atoms also takes place on the polymer surface. The concentrations of the most important oxygen species 0 and 03, produced by VUV photolysis of air and coming to the polymer surface were calculated for the air pressure range 0 .1-100torr. The photooxidation mechanism for siloxane polymers under VUV irradiation in air has been proposed.

We observe dipole resonances in thin conductive carbon micro-fibers by detecting an enhanced electric field in the near-field of a single fiber at terahertz (THz) frequencies. Time-domain analysis of the electric field shows that each fiber sustains resonant current oscillations at the frequency defined by the fiber's length. Strong dependence of the observed resonance frequency and degree of field enhancement on the fibers' conductive properties enable direct non-contact probing of the THz conductivity in single carbon micro-fibers. We find the conductivity of the fibers to be within the range of 1–5×104 S/m. This approach is suitable for experimental characterization of individual doped semiconductor resonators for THz metamaterials and devices.

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It was experimentally founded, that the size and the topology of the active additives particles in the composition of the new kinds of high performance concretes is a very important parameter (as its chemical activity), especially if the combination of these additives enables realization of nonlinear phenomena. The sample which is combination of highly dispersive silica fume and nanocarbon particles of the fulleroid type -Astralenes®, was investigated.Also, the possibility to enlarge the lifetime of the polymer components in composite concretes due to the presence of the nanoparticles of fulleroid type was determined.

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This work concern the research of the concentration dependences of the influence the micro amounts of the fine disperse silica fume and the carbon nanoparticles containing modifiers on the mobility of the fine-aggregate concrete mixtures and on the pressure strength of concrete. It was founded the high nonlinear dependences of increasing this parameters in the region of the concentration 10-3 – 10-6 % of the mass of concrete. This results provide the possibility to approach the industry application for the high performance concretes technology at the nearest time.