卷 43, 编号 12 (2017)

The absorption spectra of distilled and heavy water upon exposure to an electron beam of nanosecond duration are investigated. The changes in the absorption spectrum of distilled water after exposure to an electron beam are that the absorption band of valence vibrations of the OH groups becomes broadened, the amplitude of the valence asymmetric band increases, and a shift of the absorption maximums toward shorter wavelength frequencies and an increase in the amplitudes with insignificant band broadening are observed for absorption bands comprised of the sum of deformation and libration vibrations of water molecules and the deformation band of water. The changes in the absorption spectrum of heavy water after its irradiation with an electron beam consist in that the band of valence vibrations of the OH groups of the H₂O and HDO molecules is broadened, while the absorption band of the OH overtones of the deformation vibrations of the HDO molecule becomes stronger and the absorption range is preserved. A shift of the absorption maximum toward higher frequencies is observed for the deformation vibrations of the H₂O and HDO molecules of heavy water, and the maximum of deformation vibrations of the D₂O molecules remains unchanged.

Morozov’s stationary plasma thrusters (SPTs) operating on xenon have been successfully used in space technology for many years. At the same time, due to the high cost of xenon, now there is an increased interest in alternative working substances. One of them is krypton. Therefore, research has been conducted earlier on the features of operation and characteristics of SPTs using krypton, which have showed that they are traditional for SPTs. Here, we consider the results of studying the effect of krypton consumption on the thrust efficiency of SPTs. The importance of these results is determined by the fact that they determine the appropriate ranges of SPT regimes when working on krypton.

The method of Doppler backscattering (DBS) has been applied for the study of Alfvén oscillations in the tokamak plasma for the first time. The oscillations of the plasma rotation velocity at the Alfvén frequency have been able to be registered using DBS during the studies on the Globus-M spherical tokamak. The area of the development of Alfvén instability has been determined. The measurement of the amplitude of rotation velocity oscillations has allowed the estimation of the absolute values of the amplitudes of the oscillations of the electric and magnetic fields of Alfvén oscillations in the region of their existence in the plasma-discharge volume in tokamak.

The effect of high-temperature treatment in vacuum in the presence of carbon as a reducing agent on the luminescent properties of zirconia is studied. It is shown that an increase in the intensity of pulsed cathodoluminescence at 480 nm and thermoluminescence in the dominant peak at 500 K is due to the thermochemical coloration of the initial samples with the formation of oxygen vacancies detected by electron paramagnetic resonance. The described procedure for increasing the luminescence yield of ZrO₂ can be applied when it is used in optoelectronics, photonics, and radiation dosimetry.

An experimental study of the formation of thermocapillary structures at low Reynolds numbers and temperature gradients at the surface of the film in a wide range of the liquid viscosity is performed. The data on the distance between the jets are generalized. It is demonstrated that the transverse dimension of the structures is determined by the capillary constant and does not depend on either the liquid viscosity or the flow rate (Reynolds number of the film).

The stability of a new single-domain therapeutic antibody to the ErbB3 receptor was studied by fluorescence spectroscopy at different concentrations of a denaturing agent and temperatures. The analysis of experimental denaturation curves allowed us to build a complete thermodynamic model of unfolding and to determine all parameters of the transition: ΔG = 8.5 kcal mol^–1, T_m = 76°C, ΔH_m = 107 kcal mol^–1, ΔC_p = 1.8 kcal K^–1 mol^–1. The obtained data evidence the high stability of the antibody in a broad range of conditions, which is essential for further structural and functional studies and possible therapeutic application.

It is shown that a carbide-free bainite structure can be formed in high-carbon steel of the Fe–Si–Mn–Cr–V system using a traditional furnace facility. The structural aspects of bainitic transformation developing under isothermal conditions at 300°C have been studied by the methods of X-ray diffraction and transmission electron microscopy. Orientation relationships between crystalline lattices of γ and α phases have been established. A superequilibrium carbon concentration in the bainite α phase has been determined.

Conducting hybrid polyaniline-coated polyamide-6 fiber has been obtained and used as the basis for an organic memristive element. The proposed device exhibits resistive switching with a continuous character of conductance variation. The results show that the proposed organic memristor can be used for creating three-dimensional stochastic networks based on hybrid nonwoven materials.

Thermoelastic-deformation curves of a single-crystalline Cu–13.5 wt % Al–4.0 wt % Ni shapememory (SM) alloy have been studied. Cyclic temperature variation in a 300–450 K interval revealed an anomalous character of thermoelastic hysteresis loops with regions of accelerated straining at both heating and cooling stages. The observed phenomenon can be used for increasing the response speed of SM-alloy based drive and sensor devices. Analysis of this phenomenon in the framework of the theory of diffuse martensitic transformations showed that the anomalous character of thermoelastic hysteresis loops may be related to the influence of interfacial stresses on the dynamics of martensitic transformations in these SM alloys.

Calculations using multiblock computational technologies and a model of shear-stress transport modified with allowance for the curvature of streamlines in turbulent airflow were performed at a zero angle of attack for a semicircular airfoil containing one or two surface vortex cells with slot suction. The results showed evidence of stabilization of a nearly undetached flow and attainment of an extremal lift of C_y = 5.2 and a lift-to-drag ratio of K = 24 with allowance for energy losses for suction in the vortex cells.

A photodetector for the visible and near-IR spectral range has been created on the basis of a chemical- vapor-deposited diamond modulation-doped with boron. The detected electromagnetic radiation is absorbed in a thin Cr (7 nm)–Au (5.5 nm) bimetallic sublayer deposited on the surface of a modulationdoped diamond film comprising a highly doped (up to 5 × 10¹⁹ cm^–3) 3-nm-thick delta-layer, low-doped (~10¹⁷ cm^–3) 800-nm-thick sublayer, and highly doped (10²⁰ cm^–3) ~10-μm-thick sublayer with an ohmic Ti(50 nm)/Pt(15 nm)/Au(30 nm) contact. Holes generated in the bimetallic sublayer diffuse into diamond and are accelerated by an electric field in the low-doped sublayer to form a response photocurrent. The ampere/watt responsivity of the photodetector reaches 1 μA/W at a radiation wavelength of 445 nm and 0.18 μA/W at 1.06 μm.

A new method for nondestructive testing of coatings on exterior and interior surfaces of metal shells is proposed that is based on video monitoring of the infrared radiation emitted from the shell excited by shortterm external heating. Computer processing of the measured nonstationary field of temperature distribution on the outer surface allows defects with lateral dimensions on the order of or greater than the shell thickness to be revealed on the inner (inaccessible to observation) surface. Geometric characteristics of these defects can be evaluated.

We present a new precise method of contactless magnetometric determination of the local critical current in high-temperature superconductor (HTS) tapes, which involves (i) measurement of the spatial distribution of a magnetic field of currents induced due to magnetization of the tape by an array of permanent magnets and (ii) processing of the obtained results using a modified algorithm of solution of the Biot–Savart–Laplace inverse problem. The use of an array of permanent magnets is an important feature that distinguishes the proposed method from other existing techniques, since it allows the spatial distribution of critical current to be thoroughly analyzed over the entire tape area.