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The amorphous alloy Fe75Mo5Si6B14 has been shown for investigations. It is shown that the interval of thermal stability has expanded by 80–120 K after ion treatment of the amorphous alloy for 5–25 min, respectively. When Fe75Mo5Si6B14 amorphous alloy treated with Ar + for (5–10) minutes, the relative change in microhardness is of 2.5%–4%, that is, it is within the experimental error of 5%. When the alloy treated for 15–25 min, the microhardness decreases by 7%–13%, that is, a plasticization effect is observed. The effects of expansion of the thermal stability interval and plasticization of an amorphous alloy can be explained by the dissolution of frozen centers of crystallization. This fact is confirmed also by SEM studies of the surface morphology of the amorphous alloy. [ABSTRACT FROM AUTHOR]

The micromechanical properties of amorphous alloys Co67Fe3Cr3Si15B12 and Ni40Fe40B20 are nonmonotonically dependent on time of exposure in the magnetic field is established in the work. Magnetic treatment causes two competing processes that cause changes in the microhardness and temperature of the onset of intense crystallization. The first is fast-acting, associated with the decay of clusters (borides and silicides), that causes plasticization (reduction of microhardness by (22–27)%) and increase the temperature of thermal stability by (50–70)°C. The second process is long-term, associated with the growth of frozen crystallization centers. This process leads to a strengthening of the structure and, as a result, to decrease in the magnitude of magnetoplastic effect and the effect of thermal stability increasing. [ABSTRACT FROM AUTHOR]

The photoluminescence from the fullerene C60 thin films on array of the gold nanoparticles was studied at various energies of exciting laser photons. An enhancement of the photoluminescence of C60 film on array of Au nanoparticles was observed. The observed enhancement is due to strong local field of surface plasmon excited in the gold nanoparticles. Tuning of the exciting photon energy allowed to control the quantum yield of C60 film photoluminescence. When the exciting photon energy is close to the surface plasmon resonance, the quantum yield reaches its maximum. This fact confirms the resonant character of the surface plasmon enhancement of the studied photoluminescence of C60 film. [ABSTRACT FROM AUTHOR]

One of the most important trends in modern physics of condensed state is the study of amorphous metallic alloys in metastable state, because their properties essentially depend on the influence of external conditions, especially in the region of phase transitions. External actions, such as low temperature annealing and mechanical treatment, lead to a change in the structure and physical properties of amorphous alloys. Effect of ultrasonic mechanical activation on the structure and properties of amorphous metal alloys is studied not enough, so such research is a relevant task. The aim of the work is an experimental study of the effect of ultrasonic treatment on thermal stability of the amorphous alloy Fe76Ni4Si14B6. The results of dilatometric studies show the increase in crystallization temperature of the samples of amorphous alloy Fe76Ni4Si14B6, that is, the expansion of thermal stability interval of the alloy, after ultrasound treatment. When intensity of ultrasonic treatment is 1 W/cm2, the temperature of intensive crystallization beginning increases by 30 K regardless of processing time (1-100 min), and with intensity of ultrasonic treatment of 2 W/cm2, the temperature of intensive crystallization beginning increases by 50 K regardless of processing time (1-80 min). As a parameter for comparing the mechanical properties of the amorphous alloy before and after ultrasonic treatment, microhardness was used. Microhardness of the amorphous alloy after ultrasonic treatment is reduced by 15 %, which indirectly confirms the fact that percentage of crystalline phase in the alloy is reduced by reducing size of frozen-in crystallization centers. Increasing of the thermal stability interval of Fe76Ni4Si14B6 amorphous alloy and reducing of the microhardness can be explained by the fact that ultrasonic treatment leads to decrease in the size or dissolution of frozen-in crystallization centers, resulting in homogenization of the amorphous alloy structure. [ABSTRACT FROM AUTHOR]

The method for nanographite films preparation using thermal sublimation in vacuum of graphite nanoparticles under ultrasound treatment was proposed. Studied in the system nanographite film -- substrate were composition and morphology of a multilayer interface system by using ellipsometry and Raman scattering. It has been ascertained that the optical parameters of discontinuous nanographite films strongly depend on morphology of the surface layer. Using the results of ellipsometric measurements, we determined the effective optical constants, thickness of the films and calculated the volume composition of the solid phase in the film within the framework of the model of effective environment by Bruggeman. [ABSTRACT FROM AUTHOR]

The clinical and medico-psychological research of the servicemen, long time staying by hostages in captivity is lead. Boundary mental frustration, in particular neurotic reactions and the conditions, asthenodepressive syndrome, posttraumatic stress frustrations, are revealed in 45.8% surveyed. The most psychotraumatic is initial period of adaptation to conditions of captivity. The necessity to carry out the measures of medico-psychological rehabilitation and treatment of the servicemen, released from captivity, should be taken into account during planning of medical maintenance of the troops in local wars and armed conflicts.