Publications by authors named "A T Kozakov"

A simple analytical expression is obtained relating the radius of the core, the thickness of the shell of nanoparticles, and the intensities of X-ray photoelectron lines from the core and shell, recorded during one experiment. The effective evaluation of the proposed equation was verified by comparison with the results of calculations of the parameters of core-shell nanoparticles (NPs) using known methods, as well as by comparing the results of ratios between the radius and thickness of the shell of specific NPs and their evaluations using the transmission electron microscopy method. The formula proposed in this work also allows using EDS data to estimate the core-shell parameters of nanoparticles.

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It is shown that the potassium polytitanate powder (PPT) synthesized at 500 °C via the treatment of powdered TiO (rutile) in molten mixtures of KOH and KNO is a cheap and effective catalyst of HO chemical decomposition in aqueous solutions. At the same time, the PPT catalytic activity strongly depends on the [TiO]:[KOH]:[KNO] weight ratio in the mixture used for the synthesis, increasing with [KNO] in the order of PPT (30:30:40) < PPT (30:50:20) < PPT (30:70:0). The obtained results are explained by increased [Ti] in the PPT structure (XPS data), which is grown in this order from 0 to 4.

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Phase change metasurfaces based on VO, which are pre-heated with electric current and optically addressed by projected structured light hologram, are considered to become a new paradigm in programmed THz/middle IR flat optics. Macroscopic quasi-homogeneous arrays of Au nanoparticles show large near IR absorption and a significant photothermal effect capable of boosting a light-triggered switching of VO and are to be carefully examined. We propose a new approach to simultaneously probe the altered temperature and electric conductivity of a hybrid Au particle-VO film composite by monitoring a phase shift and attenuating a surface acoustic wave in a YX128° cut LiNbO substrate.

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The phonon and plasmon excitations and electronic properties of interfaces of periodic W/Si and Si/W multilayer structures were investigated. The Boson band originated from quasilocal surface acoustic phonons for ultrathin Si layers, excited by Raman scattering. In confined Si layers, a small fraction of crystalline Si nanoclusters were embedded within a large volume fraction of amorphous Si (a-Si) nanoclusters.

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Magnetic iron oxide nanoparticles doped with samarium were prepared by solvothermal polyol method. An introduction of 2,2'-bipyridine during the synthesis reduces the particle diameter to about 9nm in average. The difference in physical and magnetic properties of the samples prepared with and without capping agent was outlined on the basis of complex characterization by a number of experimental techniques.

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