Irradiation of detonation nanodiamonds with γ-rays does not produce long living spin radicals

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Graphene-based tunnel junction

The tunneling current in a junction formed by graphene half-planes and bilayer graphene with two possible packing types and two possible orientations of the crystal lattice is calculated by the Green’s function technique in the framework of the tight-binding approximation. It is shown that the band structure of graphene oriented toward the junction by the armchair-type edges leads to a power-law dependence of the tunneling current on applied voltage being specific for each specific kind of graphene. The characteristic features of this dependence are determined by the change in the number of transport channels with the growth of the applied voltage. For all junctions under study with zigzag edges oriented toward each other, it is found that the tunneling current exhibits characteristic peaks related to the existence of the localized edge states. The effects induced by the gate voltage are also studied. For the structures with zigzag edges, it is shown that the effect of switching off/on takes place for the junctions. The junctions formed by the graphene armchair edges do not exhibit any pronounced switching phenomena and the growth of the bias voltage results in higher values of the conductivity.     

Growth and optical properties of filamentary GaN nanocrystals grown on a hybrid SiC/Si(111) substrate by molecular beam epitaxy

The potential to grow filamentary GaN nanocrystals by molecular beam epitaxy on a silicon substrate with a nanosized buffer layer of silicon carbide has been demonstrated. Morphological and optical properties of the obtained system have been studied. It has been shown that the intensity of the photoluminescence spectrum peak of such structures is higher than that of the best filamentary GaN nanocrystals without the buffer silicon carbide layer by a factor of more than two.     

The Development of a Multiparametric Immunochromatographic Test System for the Analysis of Cardiomarkers

Moscow University Chemistry Bulletin - Abstract—An immunochromatographic test system for the combined analysis of two cardiomarkers, such as fatty acid binding protein (FABP) and troponin I...     

Theory of nematic–smectic phase separation in thin twisted liquid crystal cells

Recently it has been shown experimentally by the authors that a highly twisted thin nematic cell at low temperatures can separate into a smectic A region in the middle of the cell surrounded by twisted nematic layers at the boundaries. In this case the twist is expelled into the nematic layers and the nematic–smectic A transition temperature is strongly depressed. We present a thermodynamic theory of such a phase transition in a twisted nematic cell, taking into account that the smectic A slab inside the nematic cell can be stable only if the decrease of free energy in the smectic region overcomes the increase in distortion energy of the twist deformation in the nematic layers plus the energy of the nematic–smectic A interface. In such a system the equilibrium thickness of the smectic A slab corresponds to the minimum of the total free energy of the whole cell, which includes all the bulk and surface contributions. Existing experimental data are at least qualitatively explained by the results of the present theory. This opens a unique possibility to study the properties of the nematic–smectic interface which is perpendicular to the smectic layers.     

Study of Elastic Properties of SiC Films Synthesized on Si Substrates by the Method of Atomic Substitution

Physics of the Solid State - The elastic properties of nanoscale silicon carbide film grown on a silicon substrate by the method of atomic substitution were studied. The Young modulus of nanoscale...     

INVESTIGATION OF THE RHEOLOGICAL PROPERTIES OF ROCKS IN EXPERIMENTS ON STEPWISE LOADING OF CYLINDRICAL SAMPLES

Journal of Applied Mechanics and Technical Physics - A method for determining the empirical dependence of the rheological properties of rocks on stresses has been developed and tested in...     

Self-similar Hessian and conformally Kähler manifolds

Annals of Global Analysis and Geometry - We study a natural class of LCK manifolds that we call integrable LCK manifolds: those where the anti-Lee form $$\eta $$ corresponds to an integrable...