This work researches the impact of the temperature of compacted copper nanopowder on the amperage of the current flowing through the nanopowder sample. It was determined that upon reaching its oxidation temperature (~ 1900C), the copper nanopowder started conducting electricity, and at 280-320°C electric breakdown of sample was occurring. This is caused to irreversible processes taking place in nanomaterials during heating, such as sintering and mass-transfer, those processes leading to the formation of conductivity channels. This speaks in favor of an evident dependency between copper nanopowder conductivity and the chemical transformations taking place in it; this allows for recommending this research method for instant diagnostics of copper nanopowders.
This work describes the experience of Tomsk Polytechnic University in involving students in scientific research. The involvement is to be achieved by including scientific research elements into laboratory class programs, game-based learning, conducting laboratory classes in real-life scientific research facilities, including "Scientific research work for students" into Bachelor's curriculum (starting the second grade) and other actions. The experience described should be considered a success, as over the last decade the number of Bachelor's graduates at TPU willing to pursue the Master's degree (and then do postgraduate studies) has multiplied. The competition for enrolling into postgraduate studies has increased as well.
The microstructure of aluminum nanopowder combustion crystalline products in air and the influence of a constant magnetic field (with induction of 0.3 T) on their structures have been studied. It was revealed that in the combustion products of free-poured aluminum nanopowder two-level whiskers are present. Hexagonal single crystals are formed by combustion in air in a homogeneous magnetic field, and in case of inhomogeneous magnetic field (with induction of 0.3 T) faceted elongated crystals of micron size are generated. The crystallites of such structure are formed due to the mass transfer of the combustion products in the direction of thermal flows. Ordered six-sided crystal structures are formed by overcooling the oxidation products by the action of magnetic field and by increasing the mobility of their structural units in recrystallization thermal wave. According to electron- microscope investigation the formation of the faceted crystals is possible with optimal sizes of combustion product particles.
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