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Structure evolutions of rapidly quenched Al65Ni10Si25 alloy were investigated using DTA, X-ray diffraction, SEM, and EDX methods. The processes of structural transformation from the as-quenched state into a nanocrystalline state were studied. The common and distinctive features of structural transformation processes induced by heating, isothermal annealing, and laser irradiation were observed. The formation of the nanoscale structure was observed in all ways of treatment. Two metastable phases that were formed at different temperatures were observed: hexagonal H-phase and Al9Ni2. The phase composition in the equilibrium state was observed as Al + Si + Al3Ni. A high-temperature phase of Al6Ni3Si was found in the alloy after laser heating that shows the possibility of “freezing” the high-temperature phases in the ribbon structure using laser treatment. The fractal structure was observed on the ribbon surface after irradiation.

A numerical investigation of the influence of the thermocapillary flow of a melt of an inert component of a gasless mixture on spin regimes of combustion in a strong-instability region has been carried out. New periodic regimes of spin combustion have been found. With increase in the velocity of melt flow, the stabilization of combustion, i.e., transition from spin regimes to a quasi-one-dimensional structure of the combustion wave, occurs.

Mycobacterium tuberculosis Beijing B0/W148 is one of the most widely distributed clusters in the Russian Federation and in some countries of the former Soviet Union. Recent studies have improved our understanding of the reasons for the "success" of the cluster but this area remains incompletely studied. Here, we focused on the system omics analysis of the RUS_B0 strain belonging to the Beijing B0/W148 cluster. Completed genome sequence of RUS_B0 (CP020093.1) and a collection of WGS for 394 cluster strains were used to describe the main genetic features of the population. In turn, proteome and transcriptome studies allowed to confirm the genomic data and to identify a number of finds that have not previously been described. Our results demonstrated that expression of the whiB6 which contains cluster-specific polymorphism (a151c) increased almost 40 times in RUS_B0. Additionally, the level of ethA transcripts in RUS_B0 was increased by more than 7 times compared to the H37Rv. Start sites for 10 genes were corrected based on the combination of proteomic and transcriptomic data. Additionally, based on the omics approach, we identified 5 new genes. In summary, our analysis allowed us to summarize the available results and also to obtain fundamentally new data.

VNIIMETMASh completes modernization of an existing section continuous steel casting machine for the metallurgical plant of Baku Steel Company (Azerbaijan). The work makes it possible in CBCM-2 with base radius R = 6 m to produce round pipe billets 130, 170, 190, and 220 mm in diameter, and also square billets 130 ×130 mm in cross section.

Mycobacterium tuberculosis Beijing B0/W148 is one of the most widely distributed clusters in the Russian Federation and in some countries of the former Soviet Union. Recent studies have improved our understanding of the reasons for the “success” of the cluster but this area remains incompletely studied. Here, we focused on the system omics analysis of the RUS_B0 strain belonging to the Beijing B0/W148 cluster. Completed genome sequence of RUS_B0 (CP030093.1) and a collection of WGS for 394 cluster strains were used to describe the main genetic features of the population. In turn, proteome and transcriptome studies allowed to confirm the genomic data and to identify a number of finds that have not previously been described. Our results demonstrated that expression of the whiB6 which contains cluster-specific polymorphism (a151c) increased almost 40 times in RUS_B0. Additionally, the level of ethA transcripts in RUS_B0 was increased by more than 7 times compared to the H37Rv. Start sites for 10 genes were corrected based on the combination of proteomic and transcriptomic data. Additionally, based on the omics approach, we identified 5 new genes. In summary, our analysis allowed us to summarize the available results and also to obtain fundamentally new data.

The casting of steel on a continuous caster is the culmination of interactions that take place between the pouring equipment, mold, secondary cooling zone, and ingot withdrawal mechanism in a single process. Studies of the continuous casting of steel have shown that the stability of the continuous casting operation should be evaluated based on the criterion of lead time. Gaps in the components of the caster have a direct effect on the velocities of the mold and the ingot, which in turn determine the lead time. Hundreds of continuous-caster strands equipped with mold oscillation mechanisms of the hinge-lever type and hinged multi-component dummy bars have been in use in many countries up to the present. Thus, the effect of gaps in the caster components that determine the quality of the cast semifinished product is an important problem and needs to be resolved.

Cystic fibrosis (CF) is an inherited childhood-onset life-shortening disease. It is characterized by increased respiratory production, leading to airway obstruction, chronic lung infection and inflammatory reactions. The most common bacteria causing persisting infections in people with CF isPseudomonas aeruginosa. Superparamagnetic Fe3O4iron oxide nanoparticles (NPs) conjugated to the antibiotic (tobramycin), guided by a gradient of the magnetic field or subjected to an oscillating magnetic field, show promise in improving the drug delivery across the mucus andP. aeruginosabiofilm to the bacteria. The question remains whether tobramycin needs to be released from the NPs after the penetration of the mucus barrier in order to act upon the pathogenic bacteria. We used a zero-length 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDC) crosslinking agent to couple tobramycin, via its amine groups, to the carboxyl groups on Fe3O4NPs capped with citric acid. The therapeutic efficiency of Fe3O4NPs attached to the drug versus that of the free drug was investigated inP. aeruginosaculture.

In the present paper the fermion fields, living in the background of five-dimensional warped brane world models with compact extra dimension, are thoroughly examined. The Kaluza-Klein decomposition and isolation of the physical degrees of freedom is performed for those five-dimensional fermion field Lagrangians, which admit such a decomposition to be performed in a mathematically consistent way and provide a physically reasonable four-dimensional effective theory. It is also shown that for the majority of five-dimensional fermion field Lagrangians there are no (at least rather obvious) ways to perform the Kaluza-Klein decomposition consistently. Moreover, in these cases one may expect the appearance of various pathologies in the four-dimensional effective theory. Among the cases, for which the Kaluza-Klein decomposition can be performed in a mathematically consistent way, the case, which reproduces the Standard Model by the zero Kaluza-Klein modes most closely regardless of the size of the extra dimension, is examined in detail in the background of the Randall-Sundrum model., 42 pages, LaTeX. v2: minor corrections in the text

The institute VNIIMETMASh has designed a new sleeve named VM-sinus for the continuous casting of round semifinished products. The working cavity of the sleeve is designed so as to ensure that it comes into intimate contact with the skin of the solidifying ingot both along the sleeve and about the perimeter of its cross section. Use of the sleeve has made it possible to produce commercial-sized batches of round semifinished products having the required geometric parameters.

Unsteady filtration combustion of gases in an inert porous layer is considered taking into account the gas pressure distribution in the pores. The steady-state combustion limits in the layer as functions of depending on gas flow and parameters of interfacial heat transfer were determined. The possibility of the existence of self-oscillating filtration combustion is shown.

We discuss the symmetries of vacuum configurations in stabilized five-dimensional brane-world models and their relation to the properties of solutions of the corresponding equations of motion. With the example of a model admitting the four-dimensional de Sitter metric on the branes, we show that the existence of such symmetries in some cases leads to a decrease in the number of fundamental parameters to be fine tuned.

Unsteady propagation of a gasless combustion wave in a cylindrical sample with a stepwise varying diameter was studied numerically. For the diameter of the smaller cylinder which ignites the larger cylinder, the critical values for combustion extinction were calculated as functions of the Zel’dovich and Arrhenius parameters. At a diameter larger than the critical value, the combustion wave entered a semibounded volume of the reaction medium. The critical diameter was shown to be a characteristic of the reaction medium.

Linearized equations of motion for gravitational and scalar fields are found and solved in a stabilized brane world model in five-dimensional Brans-Dicke theory. The physical degrees of freedom are isolated, the mass spectrum of Kaluza-Klein excitations is found and the coupling constants of these excitations to matter on the negative tension brane are calculated., Comment: 12 pages, LaTeX

A mathematical model of nonisothermal synthesis in a mechanically activated system with allowance for the phase transition in one reagent is constructed. Results of studying the influence of the phase transition on the kinetics of nonisothermal chemical interaction of a pre-activated mixture for two different limiting synthesis regimes (wave and volume synthesis) are presented.

In the stabilized Randall-Sundrum model, we obtain and solve linearized equations of motion for gravitational and scalar fields in the case of matter on the brane. We find the Newtonian limit of an effective four-dimensional theory on branes with negative tension and explicitly isolate the radion field contribution.

Filtration combustion of a porous layer with natural filtration of the oxidizer diluted by an inert component is studied. The problem of ignition of a porous layer by a heated surface permeable for the gas is solved, and the time of ignition is determined as a function of pressure in the reactor and initial porosity of the sample. Formation of an inert gas “plug” preventing chemical interaction is examined. It is shown that the mean depth of conversion of the condensed reagent in the porous layer depends on the sample length, porosity, pressure of the gas mixture, and concentration of the inert component.

The effect of a heat-conducting element on the ignition and combustion of a cylindrical layer of a gasless mixture with a nonadiabatic lateral surface is studied. It is shown that the introduction of an element with high heat conductivity allows one to extend the region of ignition of the gasless composition by a heated surface and to increase burning rate under conditions of external heat release.

Background Luminescent semiconductor nanocrystals, also known as quantum dots (QD), possess highly desirable optical properties that account for development of a variety of exciting biomedical techniques. These properties include long-term stability, brightness, narrow emission spectra, size tunable properties and resistance to photobleaching. QD have many promising applications in biology and the list is constantly growing. These applications include DNA or protein tagging for in vitro assays, deep-tissue imaging, fluorescence resonance energy transfer (FRET), and studying dynamics of cell surface receptors, among others. Here we explored the potential of QD-mediated labeling for the purpose of tracking an intracellular protein inside live cells. Results We manufactured dihydrolipoic acid (DHLA)-capped CdSe-ZnS core-shell QD, not available commercially, and coupled them to the cell cycle regulatory protein Cyclin E. We then utilized the QD fluorescence capabilities for visualization of Cyclin E trafficking within cells of Xenopus laevis embryos in real time. Conclusions These studies provide “proof-of-concept” for this approach by tracking QD-tagged Cyclin E within cells of developing embryos, before and during an important developmental period, the midblastula transition. Importantly, we show that the attachment of QD to Cyclin E did not disrupt its proper intracellular distribution prior to and during the midblastula transition. The fate of the QD after cyclin E degradation following the midblastula transition remains unknown. Electronic supplementary material The online version of this article (doi:10.1186/s12951-015-0092-6) contains supplementary material, which is available to authorized users.

We consider linearized gravity in the Randall-Sundrum model in which the distance between branes is stabilized by introducing the scalar Goldberger-Wise field. We construct the second variation Lagrangian for fluctuations of gravitational and scalar fields over the background solution and investigate its gauge invariance. We obtain, separate, and solve the corresponding equations of motion. For physical degrees of freedom, we obtain the effective four-dimensional Lagrangian describing the massless graviton, massive gravitons, and the set of massive scalar fields. We also find masses and coupling constants of these fields to the matter on the negative-tension brane.

Chemical interaction between titanium and nitrogen during mechanical activation is studied. The results demonstrate that mechanical activation of titanium powder in a planetary mill leads to a thermal explosion and the formation of titanium nitride nanopowder.

The modern electric steelmaking equipment and technology in use at the Volga Pipe Plant allows that facility to make tubular semifinished products composed of a wide range of steels. Due to an increase in the volume of production and the number of orders being received for 156-mm-diam. semifinished products, the plant found it necessary to increase the productivity of the continuous caster in the casting of small-diameter products. The plant worked with VNIIMETMASh to modernize its existing continuous section caster. The technical and organizational changes that were made in order to cast 156-mm-diam. semifinished products have elevated the performance of caster No. 2 to world-class level. The modernization effort was completed well in advance of the scheduled date.

Results from experimental studies of the nonisothermal mechanochemical reaction in the titanium-nitrogen system. Experimental data are compared with simulation results. The effective kinetic parameters of mechanical activation of the reactant and the chemical reaction are determined from analytical relations. It is shown that the developed mathematical model is suitable for the analysis of the macrokinetics of nonisothermal chemical reactions in solid reactant-reactive gas systems.

A mathematical model for mechanosynthesis in solid-gas systems is constructed which includes the equations of mechanical-reactor heat balance, grinding, the excess-energy dynamics in the condensed substances, which determines the effect of mechanical activation on the chemical-reaction rate, and the reaction kinetics. A brief analysis of the model is presented. A description is given of two simplified models of independent significance derived from the general model, which can be studied by analytical methods. Synthesis in a preactivated system is studied in detail. Relations determining the characteristics of the synthesis are obtained. The accuracy of the analytical estimates is verified by numerical simulation.

A mathematical model for the combustion of preliminary activated heterogeneous systems is proposed which includes equations describing heat conduction, chemical kinetics, and the dynamics of the excess energy accumulated in condensed reagents at the stage of preliminary mechanical treatment. The excess energy decreases as a result of structure normalization and chemical transformation, whose activation energy, in turn, depends on the excess energy in the condensed reagents. The case of stationary combustion is analyzed in detail. The effect of mechanical activation on the velocity of the synthesis wave and its structure is analyzed by numerical modeling. The main conclusions are compared with available experimental data.

We review possible mechanisms of blobby transport in fusion-related plasmas. The models dealing with the effective plasma gravity and caused by both ∇⊥ T e and parallel shear of E × B drift instabilities are considered.

The effect of phase-transition parameters and chemical conversion kinetics on unsteady combustion of gasless systems with a melting reagent is studied. It is found that the change in the kinetic law and in the chemical reaction rate constant resulting from the emergence of the liquid phase in the system destabilizes the combustion. The mean front velocity in the self-oscillatory mode with an adiabatic burning temperature close to the melting point exceeds the front velocity in the steady-state mode. In this case, the front stability improves with an increase in the rate of heat withdrawal from the system and with a decrease in the burning temperature.

The dynamics of metal concentrations in the solution, suspension, sediments, and floating plants, as well as functional and structural parameters of phytoplankton and zooplankton were studied. The sorption rate of metals on suspension and the efficiency of their removal into bottom sediments decreased in the series Pb > Cu > Zn > Cd and at increasing proportion of metal aquaions in the solution. The effect of intensive renascence of green algae was recorded from the eighth to tenth day after the metal discharge into the mesocosms. This effect activated a plankton mechanism of metal removal into bottom sediments. The metal discharge led to a strong and stable depression in all groups of zooplankton.

We find exact solutions of the equations of motion for linearized gravity in the Randall–Sundrum model with matter on the branes and calculate the Newtonian limit of the model. The results established include the contributions of the radion and the massive gravitons, which essentially modify Newton's law at short distances. We consider the effects produced by “shadow” matter situated on the other brane and compare them with the effect of the usual matter for branes with positive and negative tension. We also calculate the deflection of light and Newton's law in the zero-mode approximation and explicitly isolate the contribution of the radion field.

Results of chemico-biological experiments in a natural water body with the use of model systems with Cu (II) introduced in them at different proportions of its chemical forms (natural and simulated) in the solution. The model forms used in the experiments were Cu complexes with benzyl- and hexadecylmalonic acids, simulating low-molecular dissolved organic substances. The experimental conditions were chosen based on a preliminary calculation using WATEQ–4f program. The complexes of Cu with hexadecylmalonic acid are found to be absorbed by suspensions and removed into bottom sediment more actively than other Cu forms. The toxicity of introduced Cu for the phyto- and zooplanktonic communities is found to depend on the concentration of Cu2+ aqua-ions in the solution, in the presence of which the higher concentrations of complexes with malonic acids do not exert their toxic effect.

Analytical and numerical methods are used to solve the problem of size reduction of a solid reactant in a reactive gas as applied to problems of synthesis in solid–gas systems and safe grinding of powders. Formulas are obtained that describe the dynamics of temperature, the degree of conversion, particle size, and specific interfacial area. The conditions of explosive and nonexplosive syntheses and safe grinding are determined.

A technique is suggested for evaluating the properties of alkane conformers using the parameters of internal rotation of interdependent C-C bonds. To determine the mean conformational composition of a rotational equilibrium mixture of alkane conformers, one need not exhaust the latter because the contribution of the conformation energy to alkane enthalpy can be expressed in terms of the product of tensors with further convolution over indices.

Based on the two‐temperature, two‐velocity time‐dependent model of gasless combustion, taking into account structural transformations related to the force action of the gas filtering in the pores and vitrification and volume variation of the condensed phase during the chemical transformation, self‐oscillatory combustion modes are studied. Structural transformations are shown to have a pronounced effect on the propagation pattern of combustion waves and can either stabilize or destabilize combustion. The major structural parameters appreciably affecting combustion‐wave stability are the initial porosity, particle size, and pressure.

A mathematical model is constructed for compaction of a reacting heterogeneous mixture under continuous loading. A two-component mixture containing a low-melting component is considered. Compaction of the stoichiometric mixtures is analyzed in detail. Formulas for the dynamics of structural transformations and macroscopic characteristics of the product are obtained. It is established that there are different regimes of the process, depending on synthesis conditions, physicochemical parameters of the mixture, and the load.