Each finite group is a symmetry group of some map (an “Atom”-bifurcation)

Maps are studied, i.e., cell decompositions of closed two-dimensional surfaces, or two-dimensional atoms which encode bifurcations of Liouville fibrations of non-degenerate integrable Hamiltonian systems. Any finite group G is proved to be a symmetry group of an orientable map (of an atom). Moreover, one such map X(G) is constructed algorithmically. Upper bounds are obtained for the minimal genus Mg(G) of an orientable map with the given symmetry group G and for the minimal number of vertices, edges, and sides of such maps.     

Presentation for the Partial Dual Symmetric Inverse Monoid

We give a monoid presentation in terms of generators and define relations for the partial analogue of the finite dual symmetric inverse monoid.     

Atmospheric gamma-ray and neutron flashes

Gamma-ray pulses are calculated from 2D numerical simulations of an upward atmospheric discharge in a self-consistent electric field using the multigroup approach to the kinetics of relativistic runaway electrons (REs). Computed γ-ray numbers and spectra are consistent with those of terrestrial γ-ray flashes (TGFs) observed aboard spacecrafts. The RE flux is concentrated mainly within the domain of the Blue Jet fluorescence. This confirms that exactly the domain adjacent to a thundercloud is the source of the observed γ-ray flashes. The yield of photonuclear neutrons is calculated. One γ-ray pulse generates ∼10¹⁴–10¹⁵ neutrons. The possibility of the direct deposition of REs to the detector readings and the origin of the lightning-advanced TGFs are discussed. The text was submitted by the authors in English.     

Photonic flame effect

The results of study of the photonic flame effect observed in photonic crystals and nanocomposites based on opal matrixes are presented. The effect has been discovered recently [1] and manifests itself as radiation with duration of a few seconds in the blue-green spectral region under excitation by pulsed laser light with a wavelength of 694.3 nm and a pulse duration of 20 ns.     

Nitrogen-Doped Titanium Dioxide Thin Films Formation on the Surface of PLLA Electrospun Microfibers Scaffold by Reactive Magnetron Sputtering Method

Plasma Chemistry and Plasma Processing - Nitrogen-doped thin titanium dioxide films formed by the reactive magnetron sputtering method on the surface of PLLA electrospun microfibers scaffold were...     

Synthesis and Antibacterial Activity of New N9-Substituted Acridine-9-amines

Russian Journal of General Chemistry - A method for the synthesis of N9-substituted acridine-9-amines by reacting 9-chloroacridines with 2-(2-methyl-5- nitro-1H-imidazol-1-yl)ethanamine was...