Diffusion in a disordered porous medium with localized phase transitions on the pore walls

We derive expressions for the mean ionic components densities of a solution diffusing in a disordered, porous medium. These expressions take into account interphase processes at the pore walls, such as crystallization of salts of the diffusing ionic component. Russian Friends of the Peoples University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 24–31, January, 1997.     

KP hierarchy and (1+1)-dimensional multicomponent integrable systems

New types of reduction of the Kadomtsev-Petviashvili (KP) hierarchy are considered on the basis of Sato's approach. As a result, we obtain a new multicomponent nonlinear integrable system. Bi-Hamiltonian structures for the new equations are presented.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 45, No. 1, pp. 91–104, January, 1993.     

Oscillation interaction in a nonequilibrium magnetoactive plasma

Kharkov State University: Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 31, No. 6, pp. 675–679, June, 1988.     

Luminescence of (Zn,Cd)Se,S-Cu phosphors under the simultaneous action of a sinusoidal voltage and ultraviolet radiation

Journal of Applied Spectroscopy -     

Change of the effective fluctuation dimensionality in vanadium thin films in a magnetic field

Lowering of the effective fluctuation dimensionality in the critical region has been found for thin superconducting vanadium films placed in strong perpensicular magnetic fields. The effect shows itself as a change of the critical index characterizing the temperature dependence of the excess film conductivity. By varying the magnetic field, one can observe both two-dimensional and zero-dimensional critical fluctuations on the same specimens.     

Effect of surface defects on radiative interband recombination in silicon nanocrystals highly doped with hydrogen-like impurities

The role of surface defects at the Si nanocrystal boundary during the process of interband radiative recombination is studied in the case in which nanocrystals are doped with hydrogen-like impurities with shallow energy levels. It is shown that, in the case of a nonpassivated surface with a large number of dangling bonds, the rate of radiative transitions in nanocrystals doped with donors can be larger than that in nondoped crystallites. On the other hand, doping with acceptors leads to a decrease in the rate of transitions. In the case of a completely passivated surface, the recombination rate remains almost unchanged irrespective of the type of dope.     

Fast decoding of Gabidulin codes

Gabidulin codes are the analogues of Reed–Solomon codes in rank metric and play an important role in various applications. In this contribution, a method for efficient decoding of Gabidulin codes up to their error correcting capability is shown. The new decoding algorithm for Gabidulin codes (defined over ${\mathbb{F}_{q^m}}$ ) directly provides the evaluation polynomial of the transmitted codeword. This approach can be seen as a Gao-like algorithm and uses an equivalent of the Euclidean Algorithm. In order to achieve low complexity, a fast symbolic product and a fast symbolic division are presented. The complexity of the whole decoding algorithm for Gabidulin codes is ${\mathcal{O} (m^3 \, \log \, m)}$ operations over the ground field ${\mathbb{F}_q}$ .     

Structural model of uramarsite

The structural model of uramarsite, a new mineral of the uran-mica family from the Bota-Burum deposit (South Kazakhstan), is determined using a single-crystal X-ray diffraction analysis. The parameters of the triclinic unit cell are as follows: a = 7.173(2) Å, b = 7.167(5) Å, c = 9.30(1) Å, α = 90.13(7)°, β = 90.09(4)°, γ = 89.96(4)°, and space group P1. The crystal chemical formula of uramarsite is: (UO₂)₂[AsO₄][PO₄,AsO₄][NH₄][H₃O] · 6H₂O (Z = 1). Uramarsite is the second ammonium-containing mineral of uranium and an arsenate analogue of uramphite. In the case of uramarsite, the lowering of the symmetry from tetragonal to triclinic, which is accompanied by a triclinic distortion of the tetragonal unit cell, is apparently caused by the ordering of the As and P atoms and the NH₄, H₃O, and H₂O groups.