Temperature Dependence of the Vibrational Mode of Pb1 –xSnxTe Films Grown by MBE on the GaAs/CdTe Hybrid Substrate

Bulletin of the Lebedev Physics Institute - Reflectance spectra of thin Pb1 –xSnxTe films (~60 nm) with x = 0.25, 0.53, and 0.59, grown by MBE on hybrid GaAs/CdTe substrates, are measured in...     

Modification of membrane materials used in dried blood spot technology by zinc oxide nanoparticles

The modification of hydrophilic fiberglass and cellulose membrane materials with zinc oxide has been investigated. The surfaces of zinc oxide nanoparticles was hydrophilized by modification with 3-amino-propyltriethoxysilane. It was shown using methods of Fourier transform IR-spectroscopy and scanning electron microscopy that coating with hydrophilized zinc oxide nanoparticles did not change the structure of glass fibers and membrane material, while the treatment of cellulose-based membrane materials caused irreversible changes in the structure of fibers and the material as a whole.     

Extraction from soil and gas-chromatographic determination of hexachlorobenzene

The results of the solvent extraction of hexachlorobenzene from soil with o-xylene are presented. Two procedures were developed for the extraction of hexachlorobenzene from soil; they demonstrated low detection limits for this pesticide: 5 and 0.3 μg/kg, respectively.     

Grid-characteristic method on unstructured tetrahedral meshes

The goal of this paper is to develop a grid-characteristic method intended for high-performance computer systems and implemented on unstructured tetrahedral hierarchical meshes with the use of a multiple time step and high-order interpolation, including interpolation with a limiter, piecewise parabolic interpolation, and monotone interpolation. The method is designed for simulating complex three-dimensional dynamical processes in heterogeneous media. It involves accurately stated contact conditions and produces physically correct solutions of problems in seismology and seismic exploration. Hierarchical meshes make it possible to take into account numerous inhomogeneous inclusions (cracks, cavities, etc.) and to solve problems in a real-life formulation. The grid-characteristic method enables the use of a multiple time step. As a result, the computation time is considerably reduced and the efficiency of the method is raised. The method is parallelized on a computer cluster with an optimal use of system resources.     

On the Frenkel problem of equivalent steady currents in a sphere

The Frenkel problem of substituting the 3D system of steady currents given in one of two concentric spherical regions by an equivalent system of currents (i.e., by that inducing the same external magnetic field) that is distributed over the surface of the other region is considered. A method of multipole moments providing the direct solution (without calculating the fields) of the problem is described. The case of currents with the density components represented by cubic polynomials of the Cartesian coordinates is considered as an example.     

Fused Diazepines. Synthesis of 2-Methyl-8-aryl-4,6-dihydro-5H-thieno[3',2':4,5]thieno[2,3-d][1,2]diazepin-5-ones

Russian Journal of Organic Chemistry - Heterocyclization of ethyl 2-acetyl(aroyl)-5-methylthieno[2,3-b]thiophene-3-acetates with hydrazine hydrate has been studied. A dependence of the reaction...     

Radar Absorbing NiCo Nanoparticles in Carbon Matrix of Nanocomposites in the Microwave Range

Russian Physics Journal - The paper focuses on the synthesis of NiCo/C nanocomposites comprising the Ni–Co alloy nanoparticles uniformly distributed and stabilized in a carbon matrix. The...