Two mechanisms of the interaction between atoms and solids

The chemical action of atoms on solids can be due to both direct reactions with the structural units of solids and heterogeneous recombination energy transfer to the crystal lattice.

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The suppression of magnetic level coincidences in tilted magnetic fields in the HgTe quantum well as a consequence of electronic phase transitions under quantum hall effect conditions

Spin level coincidences in the HgTe quantum well observed in comparatively weak tilted magnetic fields were found to transform into anticrossings, and gaps formed in anticrossings nonmonotonically depended on the level filling factor. This behavior was indicative of phase transitions into a quantum Hall ferromagnet state.     

The Use of IR Spectroscopy and Density Functional Theory for Estimating the Relative Concentration of Triglycerides of Oleic and Linoleic Acids in a Mixture of Olive and Sunflower Seed Oils

Optics and Spectroscopy - Infrared spectra of five samples of sunflower seed oil and five samples of cold-pressed olive oil of different brands are recorded in the range of 650–3800...     

Mechanism of erythrocyte aggregation enhancement by ultrasonic field

Effect of a standing ultrasonic wave on the spontaneous and induced (specific, immune) processes of erythrocyte aggregation is studied in vitro on the basis of the data obtained from the elastic scattering of light. The effect of the time of ultrasonic action and the concentration of the initial reagents on the enhancement of these processes is analyzed. An approximate theoretical model is developed to describe the mechanism of the enhancement of erythrocyte aggregation by an ultrasonic field and the observation of the process of interest by the turbidimetric optical method. The model provides a good agreement between theory and experiment. The results of the study are used to derive recommendations as to how to increase the resolving power of the turbidimetric method of immunoanalysis with the aid of ultrasound.     

The dynamics of accumulation of electrically active radiation defects on implantation of graded-band-gap HgCdTe films grown by MBE

The dynamics of accumulation of electrically active radiation defects under ion doping of epitaxial Cd _x Hg _1−x Te films is studied for various distributions of film composition in the implantation region. The epitaxial films were irradiated by boron ions at room temperature in the continuous regime, with the dose ranging within 10¹¹−3·10¹⁵ cm⁻², energy — 20–150 keV, and ion current density — j = 0.001–0.2 μA·cm⁻². It is found that the natural logarithm of the introduction rate of electrically active radiation defects linearly depends on the epitaxial-film composition in the range of mean projected path of implanted ions. An analysis of the experimental data shows that the dynamics of accumulation of electrically active radiation defects is determined by the epitaxial-film composition in the implantation region. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 25–28, September, 2006.     

Photoelectrical Characteristics of MIS Structures on the Basis of Heteroepitaxial HgCdTe

The voltage dependence of photo-emf in the HgCdTe/SiO ₂ /Si ₃ N ₄ and HgCdTe/AOF MIS structures is experimentally studied. The heteroepitaxial graded-band films Hg _0.78 Cd _0.22 Te were produced on the GaAs substrates by molecular-beam epitaxy. It was found that the type of field dependence of photo-emf is related to the conduction type of the semiconductor used and to the presence of near-surface graded-band layers.__________Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 35–39, February, 2005.     

Energy of intermetallide formation for 3d transition metals

By the method of a model electron-density functional, the energy of alloy formation in the systems Fe-Ti, Co-Ti, Ni-Ti is calculated as a function of the volume, concentration, and degree of long-range order. The energy benefit of the appearance of compounds FeTi, CoTi, NiTi in the CsCl structure is established. For the given compounds, the equilibrium volumes and the magnitude of charge transfer are calculated. An analysis of the ordering energy as a function of the concentration and degree of long-range order is performed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 47–51, May, 1982.     

Recombination of nonequilibrium charge carriers in epitaxial Hg1−x Cdx Te MBE films

We present the results of charge-carrier lifetime measurements in narrow-band Hg_1−xCd_xTe epitaxial structures (x=0.210–0.225) grown by molecular-beam epitaxy (MBE) using pulsed excitation by radiation at various wavelengths. In p-type epitaxial films the carrier lifetime is governed by Shockley-Read recombination at impurity-conduction temperatures. The governing factor for n-type epitaxial films is Auger recombination, with some contribution from other recombination mechanisms (surface and macrodefects). V. D. Kuznetskov Siberian Physicochenical Institute, Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 96–101, September, 1997.     

Analysis of diffuse reflection and absorption spectra of ZnO in the near-IR region

It is established that the absorption of ZnO in the near-IR region of the spectrum is determined by free electrons and chemisorbed gases. The free-electron absorption spectrum is approximated by a power function with an exponent which varies within the range 2–3, depending on the defectiveness of the specimen. Chemisorbed gases yield absorption bands at 1.37; 1.18; 1.08–1.03; 0.95–0.93; 0.85; 0.75–0.73; and 0.65–0.63 eV. The bands at 1.18 and 0.85 eV are due to chemisorbed oxygen in the states O^– and O₂ ^–, while the other bands can be attributed mainly to atomic hydrogen and OH-groups.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 86–90, July, 1988.We thank E. V. Komarov for his help in conducting the experiments.