The results of numerical study of relaxation processes in oxygen at high temperatures are presented. Collisions of particles (atoms and molecules) are described by the molecular dynamics methods ...based on trajectory calculations within the framework of classical mechanics. A complex of programs for calculating the relaxation processes in mixtures of high-temperature gases involving internal modes that describe rotational and vibrational motions in molecules and molecular dissociation and atomic recombination in the presence of a third body is described. The relaxation process is described with reference to variation in the parameters in a mixture of atomic and molecular oxygen with various initial temperatures of the translational and internal modes. The results of calculations of the structure of shock wave in oxygen with the maximum translational temperature on the front higher than 5000–11 000 K are given. The results obtained are compared with experimental data.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this paper, we describe a method for creating new custom models of partial Mössbauer spectra based on the existing ones built into the SpectrRelax program without changing the program itself by ...writing code fragments in the built-in Lua programming language. The extension of the capabilities of the SpectrRelax program is demonstrated using the example of studying hyperfine interactions of
57
Fe nuclei in quasibinary Tb(Fe
0.8
Al
0.2
)
2
and Ho(Fe
0.8
Mn
0.2
)
2
alloys with the C15 Laves phase structure. A model for processing the spectra, which simultaneously takes the composite and magnetic nonequivalence of the positions of Fe atoms in these alloys, has been created and used, which makes it possible to obtain new data about the orientation of the axis of the easiest magnetization, the anisotropy of the hyperfine magnetic field, and the effect of substitution of Al and Mn atoms for Fe atoms on hyperfine parameters of Mössbauer spectra.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Haloalkaliphilic microorganisms are double extremophiles functioning optimally at high salinity and pH. Their typical habitats are soda lakes, geologically ancient yet widespread ecosystems supposed ...to harbor relict microbial communities. We compared metabolic features and their determinants in two strains of the natronophilic species
, the only cultured representative of the class "
" (
). The strains of
were previously isolated from geographically remote Mongolian and Kenyan soda lakes. The type strain AHT1
was described as a facultative chemolithoautotrophic sulfidogen reducing or disproportionating sulfur or thiosulfate, while strain Z-1002 was isolated as a chemolithoautotrophic iron reducer. Here, we uncovered the iron reducing ability of strain AHT1
and the ability of strain Z-1002 for thiosulfate reduction and anaerobic Fe(II) oxidation. Key catabolic processes sustaining the growth of both
strains appeared to fit the geochemical settings of two contrasting natural alkaline environments, sulfur-enriched soda lakes and iron-enriched serpentinites. This hypothesis was supported by a meta-analysis of
genomes and by the enrichment of a novel phylotype from a subsurface alkaline aquifer under Fe(III)-reducing conditions. Genome analysis revealed multiheme
-type cytochromes to be the most probable determinants of iron and sulfur redox transformations in
. Phylogeny reconstruction showed that all the respiratory processes in this organism are likely provided by evolutionarily related early forms of unconventional octaheme tetrathionate and sulfite reductases and their structural analogs, OmhA/OcwA Fe(III)-reductases. Several phylogenetically related determinants of anaerobic Fe(II) oxidation were identified in the Z-1002 genome, and the oxidation process was experimentally demonstrated. Proteomic profiling revealed two distinct sets of multiheme cytochromes upregulated in iron(III)- or thiosulfate-respiring cells and the cytochromes peculiar for Fe(II) oxidizing cells. We suggest that maintaining high variation in multiheme cytochromes is an effective adaptive strategy to occupy geochemically contrasting alkaline environments. We propose that sulfur-enriched soda lakes could be secondary habitats for
compared to Fe-rich serpentinites, and that the ongoing evolution of
could retrace the evolutionary path that may have occurred in prokaryotes at a turning point in the biosphere's history, when the intensification of the sulfur cycle outweighed the global significance of the iron cycle.
Results of an experimental study and numerical simulation of the curing kinetics of an epoxy binder under the conditions of violation of the stoichiometric equilibrium of its components are ...presented. The object of research is a two-component composition of an L epoxy resin and an EPH 161 hardener, certified as a binder for composite materials of aerospace purpose. As the basic model, we used a system of two ordinary differential equations describing the behavior of the resin and hardener during the curing process. The values of material parameters necessary for calculations were obtained by a rheological method, where the viscosity of binder was analyzed as a function of polymerization time and hardener concentration. The estimates of model parameters obtained by processing data of full-scale experiments are presented. The effective values of kinetic parameters at which the calculated time of yield loss is in good agreement with the experimental one are determined. The adequacy of the model was confirmed by direct measurements using the IR spectroscopy.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Coupled nonreactive memristor generators (NMG) are considered as elements of binary-oscillator networks. In such systems, information is represented by binary streams and the exchange of binary ...signals between elements is facilitated. The principles of constructing NMGs for binary-oscillator networks are discussed. Analysis of the operation of the simplest networks based on them is carried out. The results of modeling coupled NMGs are presented.
The Marchuk model of infectious diseases is considered. Distributed control to make convergence to stationary point faster is proposed. Medically, this means that treatment time can be essentially ...reduced. Decreasing the concentration of antigen, this control facilitates the patient’s condition and gives a certain new idea of treating the disease. Our approach involves the analysis of integro-differential equations. The idea of reducing the system of integro-differential equations to a system of ordinary differential equations is used. The final results are given in the form of simple inequalities on the parameters. The results of numerical calculations of simulation models and data comparison in the case of using distributive control and in its absence are given.
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New KIZ infrasound stations (ISs) have been produced by the Typhoon Research and Production Association (Obninsk, Russia) and operated offline over several years at several locations in Russia. All ...the IS components, i.e., the configuration, microbarometers, pipe arrays, the data acquisition system, the hardware box, and other parts have been developed on the basis of the experience gained in designing and operating similar systems and, primarily, the infrasound component of the International Monitoring System for monitoring nuclear test explosions. In addition to the high and stable metrological characteristics, the main advantages of these ISs are their comparatively low cost, minimum operating expenses, reliable performance in a wide range of weather conditions, and easy metrological adjustment and calibration. The KIZ ISs are adapted to the operating conditions on a territory of a typical RF weather station.
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—A new class of nonreactive memristor generators is considered. It is shown that the double memristor generator has wide functionality for controlling and modulating output signals. The various ...operation modes of such generators are studied, including those characteristic of artificial neurons nodes, such as excitation and inhibition, control of pulse trains, and change in the repetition rate in a packet.
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9.
Immobilization of carborane derivatives on Ni/Fe nanotubes for BNCT Korolkov, Ilya V.; Kozlovskiy, Artem L.; Gorin, Yevgeniy G. ...
Journal of nanoparticle research : an interdisciplinary forum for nanoscale science and technology,
09/2018, Volume:
20, Issue:
9
Journal Article
The most important limitation for boron neutron capture therapy of cancer is the selective accumulation of boron compounds in tumor tissues in significant quantities. In this paper, we describe the ...possibility to use magnetic Ni/Fe nanotubes as carriers for boron delivery. Carborane derivatives containing 10 and 21 boron atoms per molecule were immobilized on Ni/Fe nanotubes by covalent and ionic interactions. Magnetic properties of NTs were investigated by Mössbauer spectroscopy. Structure, element, chemical composition, and morphology of obtained magnetic nanotubes were studied by XRD, SEM-EDA, and FTIR spectroscopy. Results indicate success immobilization of carborane derivatives on Ni/Fe nanotubes and great potential to use them as carriers for boron neutron cancer therapy of cancer.
Graphical abstract
ᅟ
The aspects of design of reactance-less oscillators based on memristors are considered. The requirements on load elements in the circuits of such oscillators are formulated. The equations describing ...the dynamical behavioral of the memristor oscillators with the use of linear-drift models are presented. Examples of the analysis and synthesis of oscillators using such equations are presented. The possibility of generation in the circuits under consideration of periodic signals with a waveform close to harmonic oscillations is shown.
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