Influence of surface-bound water on the electrophysical properties of MW– CNTs

This report is devoted to the investigation of a dispersed water / multiwalled carbon nanotubes system, from various degrees of humidity. Adsorption electrophysical and calorimetric behavior features of such systems are considered. The studies presented in this paper make it possible to reveal the characteristic behavior features of thin water films on the surface MWCNTs in a wide range of temperatures and frequencies. Particularly significant are the results in the area of phase transitions, which makes it possible to characterize the state of water as a bound state

Investigation electrophysical properties of allotropic modifications of carbon in the range of temperatures 140-400 K

The paper presents the results of the investigation allotropic modifications of carbon (coal, graphite, fullerenes, CNTs Dependences of conductivity on the field frequency in the temperature range 140-400 ◦K are presented. The characteristic features associated with the structure and types of hybridization are revealed. Calculation of the activation energy of carriers was performed

Investigation of activative conductivity in CNT and F-CNT in the range of temperatures 140-470 ◦K

In the work by the method of dielectric relaxation spectroscopy, activation of p-electronic orbitals in CNT and F–CNT was investigated. The activation energy of carriers in different range was estimated. Dependences of conductivity and dielectric losses on the frequency of the alternating field in the temperature range 140–470 K are presented

INVESTIGATION OF CAVITATION AND ELECTROCORROSIVE DESTRUCTION OF MATERIALS FOR SCREW SCREWS AND SHAFTS IN HYDRODYNAMIC MEDIA

This report is devoted to the study of nucleation and evolution of defects on the bronze surface by means of cavitation and electrochemical corrosion. The studies were carried out using electronic and scanning probe microscopy

Studies of stainless steel exposed to sandblasting

The influence of sandblasting on surface and subsurface of stainless steel is investigated using variable energy positron beam (VEP), positron annihilation spectroscopy (PAS), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Samples of stainless steel were blasted using 110 μm particles of Al2O3 under different pressure and time duration. In the case of sandblasting for 90 s, the reduction of positron diffusion length depending on the applied pressure was observed. Sandblasting during 30 s leads only to the reduction of positron diffusion length to about 60 nm for all samples. Positron lifetimes close to 170 ps measured using positrons emitted directly from the source point to the presence of vacancies on the dislocation lines. SEM and AFM images show that surface roughness depends rather on pressure of sandblasting than time of exposition