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Hexagonal boron nitride exhibits two types of defects with great potential for quantum information technologies: single-photon emitters (SPEs) and one-dimensional grain boundaries hosting topologically-protected phonons, termed as topologically-protected phonon lines (TPL). Here, by means of a simple effective model and density functional theory calculations, we show that it is possible to use these phonons for the transmission of information. Particularly, a single SPE can be used to induce single-, two- and qubit-phonon states in the one-dimensional channel, and (ii) two distant SPEs can be coupled by the TPL that acts as a waveguide, thus exhibiting strong quantum correlations. We highlight the possibilities offered by this material-built-in nano-architecture as a phononic device for quantum information technologies. [ABSTRACT FROM AUTHOR]

The article presents the results of laboratory testing to select the optimal flocculant for clarification of circulating water from the shaft furnace gas cleaning of the metallization department. Laboratory testing was carried out using the standard settling (clarification) technique in sedimentation glasses. It is shown that the use of a liquid emulsion flocculant with a low cationic charge and high molecular weight allows for the successful removal of suspended and colloidal substances from the circulating water of the gas cleaning system and ensures the quality of the clarified water corresponding to the standard for the content of suspended substances ≤30 mg/dm3. It is established that the optimal dosing point for the selected liquid emulsion flocculant is a zone of high turbulence and intensive mixing, i.e., the receiving chamber of the radial-flow settling tank. The proposed reagent treatment program is recommended for industrial use for clarification of shaft furnace gas cleaning circulating water of one of the metallurgical plants in Russia. The optimal dosage range of the selected cationic flocculant (according to the commercial reagent) based on the wastewater entering the radial-flow settling tank is 0.4–0.5 g/m3. [ABSTRACT FROM AUTHOR]

Transformations of 1-(dichloromethyl)adamantane and its derivatives in strongly acidic media have been studied. The nitroxylation of the title compound has been found not to be accompanied by nitrolysis of the dichloromethyl group. A series of 3-substituted 1-(dichloromethyl)adamantanes have been obtained via genera-tion of tertiary carbenium ion; the conservation of the dichloromethyl group in the products makes them promising for further modification. [ABSTRACT FROM AUTHOR]

The problem of improving the efficiency of decision making based on cases (case-based reasoning) in real-time intelligent systems is considered. Methods for preprocessing and storing temporal data are discussed. A method and algorithms for structuring the case base are proposed. The main stages of the method are the generalization of properties of dynamic parameters, the formation of classes of similar situations associated with cases from the case base, and the construction of decision trees to enable efficient search for solutions in each class. The results of a machine experiment are presented. To implement the proposed approach, a temporal database created using the Neo4j NoSQL graph database management system is used. [ABSTRACT FROM AUTHOR]

Expansion of CAG repeats in certain genes is a known cause of several neurodegenerative diseases, but exact mechanism behind this is not yet fully understood. It is believed that the double-stranded RNA regions formed by CAG repeats could be harmful to the cell. This study aimed to test the hypothesis that these RNA regions might potentially interfere with ADAR RNA editing enzymes, leading to the reduced A-to-I editing of RNA and activation of the interferon response. We studied induced pluripotent stem cells (iPSCs) derived from the patients with Huntington's disease or ataxia type 17, as well as midbrain organoids developed from these cells. A targeted panel for next-generation sequencing was used to assess editing in the specific RNA regions. Differentiation of iPSCs into brain organoids led to increase in the ADAR2 gene expression and decrease in the expression of protein inhibitors of RNA editing. As a result, there was increase in the editing of specific ADAR2 substrates, which allowed identification of differential substrates of ADAR isoforms. However, comparison of the pathology and control groups did not show differences in the editing levels among the iPSCs. Additionally, brain organoids with 42-46 CAG repeats did not exhibit global changes. On the other hand, brain organoids with the highest number of CAG repeats in the huntingtin gene (76) showed significant decrease in the level of RNA editing of specific transcripts, potentially involving ADAR1. Notably, editing of the long non-coding RNA PWAR5 was nearly absent in this sample. It could be stated in conclusion that in most cultures with repeat expansion, the hypothesized effect on RNA editing was not confirmed. [ABSTRACT FROM AUTHOR]

The article presents a method for increasing the operating time of a cyclic unit by combining the operations of torch and gas-dynamic gunning through addition of magnesium briquetted flux. [ABSTRACT FROM AUTHOR]

The paper demonstrates results of modeling arrival time of coronal mass ejections (CME) to near-Earth space with parameters of coronal dimmings in 2010–2018. We use drag-based model (DBM) for CME propagation and empirical model for quasi-stationary solar wind streams. We compared the ICME arrival time and speed forecast for events with coronal source in the central region of the solar disk based on the CME initial speed using (1) CACTus database; (2) dimming maximum intensity drop from Solar Demon database to calculate the initial speed of the CME. Results show that the methods result in similar errors. To study the possibility of predicting ICME, for which a CME may not be observed in the coronagraph for some reason, modeling of ICME was carried out using dimming parameters. In 43% of cases, ICME arrival time were forecasted with an accuracy of 24 h using parameters of dimmings in the central region of solar disk that could not be associated with any CMEs. [ABSTRACT FROM AUTHOR]

Simultaneous optimization of a family of related products can yield significant benefits compared to individual product optimization. Standardization of parts across different products and streamlining assembly and manufacturing processes can lead to reduced overall costs for the product family. In this study, we introduce a methodology for optimizing the design of a product family while considering detailed CAD models of individual products. The motivation arises from the challenge of achieving optimal product standardization without compromising individual product performance. Existing methods often impose predefined levels of commonality and seldom account for detailed CAD models and computationally expensive metrics of interest. To address this gap, we propose a novel approach that utilizes surrogate models to mitigate computational complexity and optimize the product family configuration based on total production cost, ensuring economically viable configurations while meeting performance requirements. The objective function incorporates the total production cost of the product family, including manufacturing and assembly process costs and volume discounts. Assembly process complexity and associated costs are quantified using Design for Assembly rules, while individual product performance, evaluated through finite element models, serves as a constraint. The results of the single-objective optimization, applied to a case study involving a product family comprising multiple gearboxes, demonstrate that by considering the product family, a better design in terms of the total production cost can be found compared to optimizing each product individually. Results indicate that the suggested method can efficiently identify optimal product family configurations, balancing standardization benefits with individual product performance. Overall, this study contributes to advancing methodologies for product family optimization and underscores the importance of considering detailed product designs in the optimization process. [ABSTRACT FROM AUTHOR]

Cutting production costs is a crucial instrument for companies to increase profitability and remain competitive. However, companies aim to cut costs without compromising performance requirements of the products. Commonality between components reduces the costs, while diversity between them differentiates the key attributes of the products in a product family. This commonality-diversity trade-off is the essence of the product family design optimization. Current model-based methodologies consider optimizing the design for commonality rather than cost. This article proves that higher commonality does not always amount to minimal cost and, therefore, a simple commonality index cannot replace a cost model. A tunable cost model that includes simplified formulas for standardization benefits is introduced to be used by cost optimization techniques. Current product family optimization methods are often combinatorial and perform inefficiently due to searching large design space. These methods also optimize the product family design from scratch. This limits the applicability of the current methods in industrial settings that are typically complex and brownfield. This article proposes a model-based cost optimization methodology that accelerates the cost optimization by starting from an existing design. The proposed methodology is a two-stage nested optimization algorithm, in which the commonality matrix is optimized with sensitivity analysis on component types in the outer loop and the associated design variables are optimized in the inner loop. The methodology is numerically demonstrated on an industrial example and benchmarked against state-of-the-art cost optimization methods. The proposed methodology ensures a gradual improvement in cost reduction with a significant acceleration in performance. [ABSTRACT FROM AUTHOR]

In this study, an attempt is made to analyze the published data regarding the effectors of bacterial lysis in the presence of various bacteriolytic enzymes. Despite the differences between such enzymes, it is possible to identify certain general patterns of their action on a highly complex substrate—a living bacterial cell protected by a cell wall and additional complexes of biopolymers associated with it. Chicken and human lysozymes are the best known of these enzymes. They have some structural differences but are generally very similar in properties. Understanding the characteristics of the antibacterial action of bacteriolytic enzymes present both in medications and in the human immune system is extremely important for the development of new approaches to combat bacterial infections, including antibiotic-resistant ones. Moreover, certain logical and methodological approaches used to study bacteriolytic enzymes can be extremely useful for studying and describing other enzymes that affect complex polymer substrates in real biological situations. [ABSTRACT FROM AUTHOR]

The charge-exchange reaction π - Be → A ω (782) ϕ (1020) with ω → π + π - π 0 and ϕ → K + K - is studied with the upgraded VES facility (U-70, Protvino) using a 29 GeV pion beam. The distribution of the ω ϕ invariant mass shows a near-threshold enhancement. Partial-wave analysis reveals that an isoscalar scalar state with J PC = 0 + + dominates in this mass region. Considering the observed signal as an f 0 resonance, and using the one-pion-exchange model, the product of the branching fractions into two channels B r (f 0 → π π) B r (f 0 → ω ϕ) is measured. Based on this value, a large partial width is found for the radiative decay of J / ψ into this state, which suggests a significant glueball component. The result is discussed under alternative assumptions concerning an identification of the observed signal as f 0 (1710) or f 0 (1770) . [ABSTRACT FROM AUTHOR]

This study compares samples of erosion resistant coatings made of geomat filled with crushed stone with bituminous and bitumen-polymer binders. The comparison was made several years after the production of the coatings under study. The article provides conclusions about the coating durability and the specific features of its application, as well as recommendations for using roughness coefficient. [ABSTRACT FROM AUTHOR]

The paper presents the results of industrial testing and using of reagents for circulation water clarification for gas cleaning systems at ferroalloy making plants. The process of treatment involving the combination of liquid composite coagulant AS-C2001 and powder anionic flocculant AS-FL7003 was shown to remove successfully suspended material from circulation water for gas cleaning and to reliably provide the specified amount of suspended material (less than 150 mg/L) in cold water used in gas cleaning. The proposed process of treatment with the mentioned reagents has been employed for more than 6 years at the section of water preparation for the gas cleaning installation of the reduction furnace at one of the ferroalloy plants in Kazakhstan. [ABSTRACT FROM AUTHOR]

Abstract—The growth mechanism of monolayer on the top facet of Ga-catalyzed GaAs and GaP nanowires is investigated. Within the framework of a theoretical model, the maximal monolayer coverage due to the material in the catalyst droplet, the nanowire growth rate and the content of group V atoms in the droplet are found depending on the growth conditions. The estimates of the phosphorus re-evaporation coefficient from neighboring nanowires and substrate are obtained by comparing the theoretical and experimental growth rate of Ga-catalyzed GaP nanowires. [ABSTRACT FROM AUTHOR]

The authors demonstrate the possibility of using CubeSat nanosatellites to study solar cosmic rays (SCRs). SCR electron fluxes over the polar caps at altitudes of ∼550 km are detected. Measurements are made using scintillation detectors of cosmic radiation (DeCoR) mounted on several CubeSat nanosatellites of Moscow State University during an SCR event on September 6–21, 2022. [ABSTRACT FROM AUTHOR]

The parameters of dimmings and their relation to coronal mass ejections (CMEs) are studied to determine the location of possible sources of ejections on the solar disk during solar cycle 24. We used the Solar Demon database, which contains information on flares and dimmings obtained by processing images from the SDO/AIA space observatory. Of all the analyzed dimmings, 16% are аssociated with CMEs from the CACTus database using SOHO/LASCO coronagraph data for 2010–2018. Based on the parameter distribution, it is found that dimmings related with CMEs are on average events with large absolute parameter values. The correlation coefficient between the position angle of the dimmings and the position angle of the CME associated with them is 0.96. For dimmings observed in the central part of the solar disk, we obtained correlation coefficients between the CME velocity and dimming parameters that are close to 0.5. The results can be used to model the propagation of CMEs and to refine the probability of their arrival to the near-Earth orbit. [ABSTRACT FROM AUTHOR]

This study aimed to investigate myoneural transmission in the presence of capsaicin, which acts as an integrator of pain stimuli and causes heat sensation. The effects of purines that participate in synaptic transmission, such as ATP and adenosine, in the presence of capsaicin were explored. When the neuromuscular preparation of frog was perfused with solution containing capsaicin, the inhibitory effects of both purines were significantly reduced. A reduction of the depressant effects of adenosine is associated with the inhibition of A1 signaling, since the A2A receptor agonist CGS21680 showed a pronounced potentiating effect in the presence of capsaicin, which was almost completely hidden in the control. Our findings suggest that the known neuroprotective effect of capsaicin is primarily due to elimination of inhibition by endogenous purines of the induced quantum output of the neurotransmitter. [ABSTRACT FROM AUTHOR]

The solution of tasks of detection and classification of defects of printed circuit boards using machine learning is discussed in this article. Six classes of defects are defined. We carried out manual annotation of defects on images of printed circuit boards in Roboflow. The YOLO v.8 neural network model was used with the settings of its training parameters. To improve the accuracy of defect detection we have expanded the dataset and have conducted the experiments. The results of the automatic search for defects in printed circuit boards are presented and explained. [ABSTRACT FROM AUTHOR]

This article analyzes the existing approaches to assess and account for the components used in software, including open source software. The existing frameworks for assessing software development processes, including information security, are analyzed. The typical risks of using open source components and free licenses are considered. The possibility of assessing development processes to identify threats to information security in open source projects and the need to automate this process in order to ensure the efficiency of dependence management in projects that use open components as dependencies are noted. [ABSTRACT FROM AUTHOR]

A finite element method is presented for calculating hydrodynamic noise excited by turbulent fluid fluctuations in the presence of an elastic body. The conventional approach to solving this problem by direct solution of the Lighthill equation requires a large amount of calculations. It is demonstrated that the situation is considerably simplified when noise components are calculated at relatively low frequencies, which correspond to wavelengths that exceed the dimensions of the turbulent zone. In this case, the noise field can be expressed in terms of turbulent fluctuations in pressure on the surface of an elastic body, which is found in the incompressible fluid approximation. The article is based on a report presented at the IX Russian Conference "Computational Experiment in Aeroacoustics and Aerodynamics," Svetlogorsk, September 26–October 1, 2022. [ABSTRACT FROM AUTHOR]

The influence of a permanent magnetic field on macro- and nanoscopic properties of triglycine sulfate (TGS) crystals with impurity chromium (TGS-Cr) has been investigated. This work continues the previous studies of magnetically induced effects in ferroelectrics. A specific feature of TGS crystals is the presence of a nanoscale relief on a polar (010) cleavage; this nanorelief is a qualitative characteristic of the crystal defect structure. It is shown that the exposure of a crystal in a magnetic field of 2 T leads to a change in its dielectric properties, accompanied by a long-term transformation of the nanorelief. The results obtained are indicative of a magnetically induced change in the defect crystal structure. A qualitative difference is found between the magnetically induced effects in TGS-Cr crystals and undoped TGS crystals. The relationship between the magnetically induced effects and structural defects is discussed. [ABSTRACT FROM AUTHOR]

The paper considers the possibilities of computerization of early diagnosis of complex vision pathologies by an example of retinal diseases. Source data for the intelligent analysis are given by electroretinography (ERG) data, which are processed by complex system analysis methods (Fourier series expansion, spectral analysis, and analysis of the amplitude and phase frequency responses of the retina in different test conditions), artificial intelligence methods (fuzzy logic and production rules formed on the basis of expert knowledge of physiologists), and methods of cognitive graphics for the graphical representation of the retina state. The work is carried out by specialists at the National Research University MPEI and the Helmholtz National Medical Research Center of Eye Diseases through the development of intelligent decision support systems (IDSSs) for early diagnosis of pathologies. [ABSTRACT FROM AUTHOR]

4-[4-Bromo-2-(2-phenyldiazenyl)phenoxy]phthalonitrile was obtained by the reaction of 4-nitrophthalonitrile and sodium 4-bromo-2-(2-phenyldiazenyl)phenolate. Magnesium and zinc phthalocyaninates were synthesized by the template condensation of the corresponding metals with phthalonitrile. The luminescence properties and photosensitization of singlet oxygen for the synthesized complexes were studied. [ABSTRACT FROM AUTHOR]

The paper is devoted to solving the problem of scheduling the work of the call center staff. A model of integer linear programming is formulated, the problem is shown to be NP-hard, and a genetic algorithm is proposed that takes into account the specifics of the problem. An experimental comparison of optimal solutions obtained using the CPLEX package with solutions found by the genetic algorithm is carried out. The computational experiment has shown the practically acceptable accuracy of the solutions obtained by the genetic algorithm and its applicability to large-dimensional problems. [ABSTRACT FROM AUTHOR]

Thoracic spinal cord injuries are well known to entail the degradation of spinal motoneurons, accompanied by axonal degeneration. In the present study, the functional integrity of neuromuscular transmission was assessed via stimulation mechanomiography in Wistar rats. We demonstrated a decrease in the modulating activity of ATP in the cholinergic synapse due to spinal cord injury (a model of spinal cord contusion injury) vs. hypodynamia (a model of anti-orthostatic hindlimb suspension). The revealed abnormal purine-mediated modulation of the neuromuscular junction provides evidence for axonal degeneration and suggests that trans-synaptic degeneration of motor neurons may occur below the spinal cord injury level in patients with similar traumas. [ABSTRACT FROM AUTHOR]

The roughness coefficients of erosion-control coatings based on geomats are studied. The roughness coefficients were calculated following an analysis of relevant publications. The process of determining the roughness coefficient of geomats filled with crushed stone and bitumen-polymer binder is described. Existing formulas for calculating the roughness coefficient of geomats are analyzed to identify the most optimal approaches. The obtained roughness coefficient values are compared with those reported in other studies on similar coatings. [ABSTRACT FROM AUTHOR]

The Ruddlesden‒Popper phases pertain to numerous promising materials with the mixed ionic-electronic conductivity used in devices such as oxygen-conducting membranes, solid oxide fuel cells (SOFC), and electrolyzers, which operate in the intermediate temperature region. Their high total conductivity and oxygen mobility make these materials candidates for the mentioned applications. The structure, the oxygen mobility, and the electrochemical characteristics of the promising materials La1.7Ca0.3Ni1 –xCuxO4 + δ (x = 0–0.4) are studied. According to the high-precision XRD data, all synthesized materials are single-phased and have the tetragonal structure. The unit cell parameter c and the cell volume increase upon doping with copper. The content of overstoichiometric interstitial oxygen decreases with doping and the compositions with the high copper content become oxygen deficient. The samples are characterized by the nonuniform oxygen mobility. By and large, the trend for the decrease in the oxygen mobility with the increase in the Cu content is observed in the series of La1.7Ca0.3Ni1 –xCuxO4 + δ samples. By impedance spectroscopy studies, it is shown that the electrodes with the La1.7Ca0.3Ni1 –xCuxO4 + δ functional layers with the copper content x > 0.2 have a higher electrochemical activity. The factors responsible for the efficiency of electrodes are analyzed. The results obtained in this study demonstrate that La1.7Ca0.3Ni0.6Cu0.4O4 + δ materials are the candidates for the air electrodes in electrochemical devices. [ABSTRACT FROM AUTHOR]

This paper proposes an approach to the development (formation and implementation) of an ontology for a complex multiconnected dynamic subject/problem area on the basis of graphs with multiple and heterotypic connections. Necessary definitions and formal dependences are given. The efficiency of this approach is demonstrated in the application to the example of a complicated technical security system for an extensive perimeter including some objects with multiple and heterotypic connections. The possibilities of implementing the proposed approach with the application of contemporary graph systems for the management over the databases supporting the concept of the non-relational organization (model) of NoSQL data (e.g., Neo4j, TigerGraph) are considered. [ABSTRACT FROM AUTHOR]

A new technique has been developed for the synthesis of cross-linked catalase aggregates by treatment of the enzyme incorporated into the pores of vaterite microspheres with glutaraldehyde and subsequent dissolving of the inorganic matrix. The resulting aggregates have a spherical shape, a narrow particle size distribution, and a high specific activity. The number and enzyme activity of the cross-linked aggregates strongly depends on the rate of the matrix dissolution: mild conditions of dissolution made it possible to increase the number of formed protein particles, whose residual catalase specific activity was only 2 times less than that of the native enzyme. The storage stability of the cross-linked aggregates is comparable to that of the native enzyme of the same concentration. [ABSTRACT FROM AUTHOR]

The dynamics of the phase transition (PT) in triglycine sulfate crystals, either nominally pure or doped in different ways (upon homogeneous and profiled impurity introduction into the crystal) with chrome impurity (Сr3+), has been studied by analyzing the dielectric spectra measured in the ranges of frequencies 1–107 Hz and temperatures 23–60°C upon heating and cooling. It is shown that the introduction of impurity shifts the PT temperature range both upon heating and cooling. The PT temperature dynamics is found to depend both on the presence of impurity and on the way of its introduction into the crystal. The dependence of the width of the PT temperature range on the frequency at which the dielectric spectra were measured was shown to increase directly proportion to frequency. [ABSTRACT FROM AUTHOR]

Identification of the pre- and postsynaptic effects of ATP is a methodological challenge. In our previous study, the role of P2 receptor signaling in synaptic transmission processes was evaluated using carbachol-induced skeletal muscle contractions. The search for models that can record the postsynaptic side of purinergic signaling during the application of electrical stimulation led to the idea of controlling the presynaptic terminal of ATP-mediated modulation. In in vitro experiments, electromyograms and mechanomyograms during isometric contractions of isolated nerve-muscle preparations of rat soleus and extensor digitorum longus (EDL) muscles revealed postsynaptic effects of ATP in the presence of a high intracellular calcium level. Thus, the effects of ATP in the presence of increased Ca2+ content were seen through contraction of soleus muscles that started to contract quicker by fifty percent and inhibition of contractility of EDL muscles; this was in accord with data obtained earlier on carbachol-induced contractions. We have demonstrated an ATP-dependent processes in the postsynaptic site that may contribute significantly to adaptation mechanisms in hypothermia. [ABSTRACT FROM AUTHOR]

In this paper we consider two closely related problems of selecting a diverse subset of points with respect to squared Euclidean distance. Given a set of points in Euclidean space, the first problem is to find a subset of a specified size M maximizing the sum of squared Euclidean distances between the chosen points. The second problem asks for a minimum cardinality subset of points, given a constraint on the sum of squared Euclidean distances between them. We consider the computational complexity of both problems and propose exact dynamic programming algorithms in the case of integer input data. If the dimension of the Euclidean space is bounded by a constant, these algorithms have a pseudo-polynomial time complexity. We also develop an FPTAS for the special case of the first problem, where the dimension of the Euclidean space is bounded by a constant. [ABSTRACT FROM AUTHOR]

A semiclassical (light classical and molecule quantum) model describing the dependence of DNA/RNA dimerization rate as function of the ultraviolet C (UVC) radiation's intensity is proposed. Particularly, a nonlinear model is developed based on the Raman-like processes in quantum optics. The main result of the theory shows that the process of dimerization in the DNA/RNA depends strongly on the UVC light's intensity, thus proving a possible quantum microscopical mechanism of the interaction of UV light with the DNA. To corroborate the theoretical findings, we realize some experiments, by which want to investigate how the inactivation rate of the yeast colonies depends on the intensity of the UVC irradiation. The experimental results evidence a nonlinear decreasing of the residual yeast colonies as a function of the intensity in the irradiation process. The possibilities to optimize the intensity of UVC radiation in the considered decontamination equipment by using metamaterials are studied. The application of such equipment in disinfection of fluids (air, water, droplets, etc.), as well for the SARS-CoV-2-infected aerosols, is discussed. [ABSTRACT FROM AUTHOR]

The possibility of replacing thin plates (0.5 mm) of AA2024 grade alloy by plates made of a novel alloy of the Al–Mg–Sc system doped with transition metals is studied. The novel material is lighter than AA2024 alloy while retaining such properties as a high level of corrosion resistance and satisfactory weldability, equaling the aforementioned alloy in static strength, ductility, and crack resistance. It is shown that, upon using extrusion through the matrix with a periodically changing profile, the accumulated strain factor exhibits an almost twofold increase in comparison with the extrusion through a cone matrix. This makes it possible to improve the refinement of the structure at the same elongation ratio amounting to 4. It has been shown that a mixed structure with small-angle dislocation subgrain boundaries and strongly disoriented boundaries of fragmented structures is formed within the plates with a thickness of 0.5 mm. [ABSTRACT FROM AUTHOR]

Using the method of sintering by microwave heating at a rate of 10–100°C/min to a temperature of 1250 °C without isothermal hold, we obtain ceramic samples with the composition Ba0.75Sr0.25TiO3. The experiments are performed on a gyrotron complex for the high-temperature microwave treatment of materials, which is operated at a frequency of 24 GHz with a maximum power of 5 kW. The features of the formation of a solid solution in the sintered samples are analyzed. The dependence of the intensity of recrystallization growth of grains on the microwave-heating rate during the sintering is demonstrated. The permittivity of the samples obtained by microwave sintering with heating rates of 10 and 30 °C/min amount to 3600–4400 in the frequency range 25Hz–3MHz at room temperature. [ABSTRACT FROM AUTHOR]

The results of laboratory testing on the selection of reactants for clarification of gas scrubbing system water for ferroalloy production are presented. It is shown that the use of a reactant treatment program, including a combination of liquid composite coagulant AS-C2001 and anionic powdered flocculant AS—FL7003, makes it possible to successfully remove suspended solids, turbidity and color from gas scrubbing system water. The recommended reactant treatment program is proposed for industrial testing at the gas scrubbing system water treatment area of reduction furnaces at one of the ferroalloy plants in Kazakhstan. [ABSTRACT FROM AUTHOR]

In a hybrid micromaser system consisting of an optical cavity with a moving mirror connected to a low-temperature thermal bath, we demonstrate, both analytically and numerically, that for certain interaction times between a random atomic flux and the optomechanical cavity, vacuum phonon trapping states are generated. Furthermore, under the approach of the master equation with independent phonon and photon thermal baths, we show that the trapping of the phonons and photons is achieved for the same interaction times. The results also indicate that by increasing the cavity-oscillator coupling, one may generate a coherent phonon state aside from the trapping states. Within the same hybrid system, but now connected to the squeezed phonon reservoir, a phonon blockade effect can be engineered. Moreover, we identify an interconnection between the trapping and blockade effects, particularly if one approaches the vacuum trapping state, strong phonon blockade can be achieved when the system is connected with a weakly squeezed phonon reservoir. [ABSTRACT FROM AUTHOR]

Using hydroxyapatite as an example, first results of research on a new additive method of manufacturing ceramic products are presented. The method consists of repeated sequential application of suspension layers with high content of powder material and their rapid 24 GHz microwave sintering. The stability of aqueous suspensions of hydroxyapatite powder with submicron particle size depending on the pH of the dispersion medium and dispersants was studied. Suspensions with a high value of the solid load mass and a fluidity sufficient to ensure the continuity of layers applied by the doctor blade method were obtained. By the method of layer-by-layer microwave sintering with a heating rate of up to 30°C/min and a maximum temperature of up to 1330°C, ceramic samples with a closed system of micron-sized pores and a density of up to 92% of the theoretical value were obtained. [ABSTRACT FROM AUTHOR]

A two-dimensional material – Mg2B4C2, belonging to the family of the conventional superconductor MgB2, is theoretically predicted to exhibit superconductivity with critical temperature Tc estimated in the 47–48 K range (predicted using the McMillian-Allen-Dynes formula) without any tuning of external parameters such as doping, strain, or substrate-induced effects. The origin of such a high intrinsic Tc is ascribed to the presence of strong electron-phonon coupling and large density of states at the Fermi level. This system is obtained after replacing the chemically active boron-boron surface layers in a MgB2 slab by chemically inactive boron-carbon layers. Hence, the surfaces of this material are inert. Our calculations confirm the stability of 2D Mg2B4C2. We also find that the key features of this material remain essentially unchanged when its thickness is increased by modestly increasing the number of inner MgB2 layers. [ABSTRACT FROM AUTHOR]

To intensify the heat and mass exchange processes in a liquid melt bath of the oxygen, 160-ton capacity, converter, we tested the pulsating action of the bottom inert gas blowing at the frequencies of 0; 0.5; 1.0; 1.5 Hz. The rational value of the pulsation frequency is 2.5 Hz: under that frequency impact, the residual vanadium in the metal melt decreases from 6.41 to 6.17%, with a reduction of the exhaust gas mass yield, the heat fraction of the exothermic reactions, and the thermal efficiency of the unit. The long-term tests of the rational pulsation mode (80 thousand melts) confirm the possibility of increasing the yield of the carbon semi-product by 2.932% with the vanadium losses decrease from 6.42 to 5.74%, that is, by 10.59 rel. %. [ABSTRACT FROM AUTHOR]

The plasma technology for producing powder from fuel-rod fuel that failed an engineering requirements audit is validated. The fundamentals of nucleation of a steam–gas system under different conditions are analyzed. The structure of dispersed particles formed during cooling of low-temperature plasma is shown for a mixture of uranium and plutonium dioxides. Methods for controlling the size of these particles are substantiated. It is shown that the most effective of the available methods are cooling rate reduction and use of weak external magnetic fields. [ABSTRACT FROM AUTHOR]

An approach to recognition of malicious behavior based on analysis of the Security.evtx security log of Windows operating system upon investigation into a security incident is given. The use of an autoregression model is experimentally tested (Change Finder algorithm), from which the malicious activity of the users of the domain in the corporate network is revealed. [ABSTRACT FROM AUTHOR]

Problems of secure communications on the Internet and anonymous access to network resources are considered. A problem is revealed, which involves an increase in the probability of deanonymization of TOR network users when using the servers under common administrative control in one chain. An approach to recognition of "hidden groups" of servers of TOR anonymization network through analysis of the server characteristics frequency and their clustering based on similarity is suggested. These studies demonstrate the approaches to improve software of the TOR anonymization network and increase user security. [ABSTRACT FROM AUTHOR]

An approach to detect covert channels (C2-channels) based on the DNS protocol is considered. It involves identifying beacon signals or certain traffic signatures, which, in turn, are indicative of malware activity. An analysis of samples of real DNS traffic is carried out followed by approximation using a known statistical distribution. The time parameters of beacon signals sent at different frequencies are modeled and the optimal (according to the Neumann–Pearson criterion) detection threshold is determined. This threshold minimizes the probability to detect a false beacon signal. The results allow improving preliminary configuration of intrusion detection systems operating on a statistical approach to analyze network traffic parameters. [ABSTRACT FROM AUTHOR]

The results of experimental investigations of laser purification of the outer surface of a fuel-rod tube from microparticles are presented. It was shown experimentally that Nd laser radiation with intensity 17.8–27.8 kW/cm2 and duration 1.5 msec removes adhered UO2 microparticles from the surface of a fuel- rod tube. The processed fuel-element meets the roughness specifications. The heating of UO2, PuO2, ThO2, and CeO2 microparticles by CO2 laser radiation was modeled. Modeling shows that 10.6 μm pulsed laser radiation with duration 50 nsec can be used for laser decontamination of uranium-plutonium fuel microparticles welded into the weld seam. In addition, UO2 and PuO2 microparticles are simultaneously heated to the boiling point. [ABSTRACT FROM AUTHOR]