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This letter presents the design of five-cell cascode distributed amplifiers (DAs) in the WIN Semiconductor PIH1-10 enhancement-mode GaAs pHEMT process. Single- and two-stage DA monolithic microwave integrated circuits (MMICs) are demonstrated, with die areas not exceeding 2.5 x 1.5 mm² and same-polarity supply and bias voltages. The cascode cells are stabilized using an RC drain-gate feedback network at the common-gate transistor of each cell, and a stability analysis is presented. All transistors have a gate width of 2 μm x 75-μm, with 750-μm total common-source gate periphery per single-stage design. The measured small-signal gain is 11.5 dB with 2.6 dB flatness and 23.2 dB with 3.2 dB flatness for the one- and two-stage amplifiers, respectively, from 10 MHz to 22 GHz. The amplifiers produce over 20-dBm output power at 3-dB gain saturation across the band.

The results of the analysis of the features of the power exchange process in switched capacitors are presented. The methods are outlined to ensure high efficiency of charge pumping. The features of switching processes in transient operation modes are investigated. Circuit modeling made it possible to establish the sources of losses accompanying power conversion and heat release. The recommendations are made to optimize parameters of converter components and generate control signals.

The use of fluorspar in modern metallurgical slags, incl. slags of the argon-oxygen decarburization (AOD) process, as a fluxing agent, is associated with many disadvantages. Those disadvantages can be solved by using boron oxide as an alternative, which also provides conditions for direct microalloying of steel with boron. The paper presents the results of thermodynamic modeling of the effect of basicity and boron oxide content in slags of the CaO–SiO2–B2O3–Cr2O3–Al2O3–MgO system on the equilibrium interphase distribution of sulfur and boron, and their equilibrium content in the metal. Modeling was carried out using the HSC 8.03 Chemistry software package (Outokumpu). Slag from the desulfurization period of the AOD-process was used as the oxide phase. As a result, it was shown that, in the range of basicities 2.0-2.5 and a content of 2-4% B2O3, it is possible to carry out desulfurization of the metal, providing a sulfur content of 0.001-0.007%, and simultaneous microalloying of steel with boron in an amount of up to 0.0103%.

The methods of analysis of transients in three-phase circuits with distributed parameters and interphase connections are considered on the basis of representation of such circuits by multipoles, finding their corresponding concentrated parameters and determination of boundary and initial conditions of transients. The formulation of this scientific problem is justified by the current trend in theoretical electrical engineering to consider multiphase circuits as a series-parallel connection of different n-poles, which improves the calculation of transient electromagneticprocesses in multiphase circuits with distributed parameters and interphase connections. Using thetheory of multipoles allows us to represent the elements of the electric circuit by macromodels thatreflect their external connections and the impact on the rest of the circuit. The main difficulty inapplying this principle is to resolve emerging electromagnetic bonds.

The article considers the issues of increasing energy efficiency of 6-10 kV controlled capacitor plants of power supply systems of energy-intensive facilities due to more accurate compensation of reactive power. Analysis of the most common circuits for connecting batteries of static capacitors using semiconductor and electromechanical switches was carried out.The feasibility of using a simplified approach of determining the optimal structure of the power part of high-voltage plants for compensation of reactive power according to the criterion of minimum cost and minimum level of electric energy losses is determined. The possibility of parametric optimization of high-voltage capacitor batteries to higher voltage levels is shown, taking into account the given specific requirements of these electric power facilities.

Non-inductive (throttle-free) DC/DC converters are used in low-power and highly integrated electronic systems. A circuit analysis of the basic topologies of non-inductive DC/DC charge-pumped converters which perform typical DC-voltage conversions, i.e., lowering, raising and inverting, was carried out. The galvanic isolation between the input and output circuits of the converter was achieved even in the integrated version due to forming a time delay of the switches (Dead Time, DT), commuting a “flying” capacitor, which is transferring the charge to the storage capacitor and the load. A circuit of the DT driver was developed and its parameters, at which the through-current flow in the switch is prevented and the conditions of galvanic isolation of the input and output circuits are satisfied, were studied. The simulation was built with a popular Electronics Workbench software, widely used in training of specialists in radio electronics at higher educational institutions. The results of the study of the basic power characteristics of DC/DC conversion, such as output current and voltage, voltage transfer coefficient, efficiency, output equivalent resistance, were presented. The efficiency of conversion was estimated by varying the capacities of the “flying” and storage capacitors, the resistance of the switches in the closed state, and the frequency of switching. It is proved that the charge pumping method is simple and effective at low load currents (mA units), when both the voltage transfer coefficient from input to output and efficiency are high, and are approaching to “one”. However, with the increase of the load current, the voltage transfer coefficient and efficiency decrease, the output voltage ripples increase.

Tissue engineering has significant potential for solving the problems of durability of biological tissues when used in cardiac and vascular reconstructive surgery. A decellularization technology has been proposed for obtaining a biomaterial, morphologically and functionally similar to the damaged human heart tissue. This review discusses various aspects and models of biological tissue decellularization, including the modern technology of using supercritical carbon dioxide as the most eco-friendly and promising method.

The paper presents the results of the effect of boron, manganese and sulfur on the microstructure and mechanical properties of pipe steel 17G1SU. It was shown that the microstructure of boron-free steel sample containing 1.4% Mn and 0.01% S consists mainly of ferrite and a small amount of perlite. Samples microalloyed by boron are represented by a dispersed ferritic-bainitic structure. A decrease in ferrite grain size from 8.7 μm, in a comparative sample without boron containing 1.4% Mn and 0.010% S to 5.8 μm in a sample of steel containing 0.006% B, 1.6% Mn and 0.011% S, shows increasing the dispersity of the ferritic-bainitic structure. A decrease in the manganese content to 1.4, sulfur to 0.004% and an increase in boron concentration to 0.0011%, despite an increase in grain size to 6.8 μm, retain a fine-grained structure. The effect of boron, manganese, and sulfur content on the microhardness of the structural phases of the studied pipe steel samples is noted. The smallest microhardness of ferrite and perlite is observed in the base sample without boron, reaching 180 and 214 HV10, respectively. The microalloying of pipe steel containing 1.6% Mn, 0.011% S with boron is accompanied by an increase in the microhardness of the bainitic phase to 314 HV10, which increases to 400 HV10 with an increase in boron concentration to 0.011%, and a decrease in the content of manganese and sulfur to 1.4 and 0.003%. In this case, the microhardness of the ferrite phase, reaching an increase to 260 HV10, is practically independent of the content of boron, manganese, and sulfur. The mechanical properties of the experimental metal rolling with a thickness of 10 mm provide the production of rolled steel of strength class X80, without heat treatment, regardless of the content of boron, manganese, and sulfur, as a result of the formation of a finely dispersed ferrite-bainitic structure.

The results of fundamental studies of the physicochemical properties of slags of the CaO–SiO2–B2O3–Al2O3–MgO system were used as the basis for the development of the technology for the formation of boron-containing slags in ladle-furnace units (LFU). The recommended composition of ladle slags (1–4% B2O3, 15% Al2O3 and 8% MgO) ensures the development of direct microalloying processes of steel with boron, low viscosity, not exceeding 0.32 Pa∙s, and preservation of sufficiently high refining properties. Colemanite (Turkey) was used as boron-containing raw material, having, %: 39–41 B2O3, 26–28 CaO, no more than 5% of SiO2 and 3% of MgO. The implementation of the developed technology of direct microalloying of structural steels of a wide grade composition by boron in the BOF shop of ArcelorMittal Temirtau JSC provided the boron content at the level of 0.001–0.008%, a decrease in the consumption of manganese-based ferroalloys from 0.3 kg/t of 08кп steel to 0.8 kg/t of steel 17Г1С-У, exclusion of additives into the ladle of ferroboron and fluorspar. The proposed mode of formation of slags of the recommended composition in the melt of LFU provided a sufficiently high degree of metal desulfurization in comparison with the existing production routes. For example, with pipe steel 17Г1С-У, despite a decrease in lime consumption by 500 kg per a heat and a decrease of the steel processing time at the LFU by 40 minutes, a high degree of desulfurization, reaching 66.7%, provided a sulfur content of 0.004% in the metal. Microalloying of structural steels by boron results in their high strength properties with invariance of plasticity apart from sufficiently high refining effect.

Thermodynamic modeling of the reduction of cerium from slags of the CaO–SiO2–Ce2O3 system containing 15% Al2O4 and 8% MgO, with aluminum dissolved in the metal together with calcium carbide additives at temperatures of 1550 and 1650°C was performed using the HSC 8.03 Chemistry software package (Outokumpu) based on the simplex lattice planning method used to minimize Gibbs energy. The results of thermodynamic modeling are presented in the form of composition-property diagrams (equilibrium content of cerium in the metal) for temperatures of 1550 and 1650°C. It is shown that the formation of slags within a basicity range of 2–3 containing 1–7% Ce2O3 provides an equilibrium concentration of cerium in the metal varying from 1 to 7 ppm at a temperature of 1550°C. The displacement of slags in the area of increased basicity (up to 3–5) is accompanied by an increase in the equilibrium concentration of cerium in the metal up to 7–23 ppm with a content of 3–7% Ce2O3 and as a consequence an increase in the efficiency of the process of cerium reduction. At a temperature of 1650°C, the equilibrium concentration of cerium in the metal within the basicity range of 2–3 and having a Ce2O3 content of 1–7% varies from 2 to 12 ppm. The displacement of slags in the area of increased basicity (up to 3–5) is accompanied by an increase in the equilibrium concentration of cerium in the metal to 7–33 ppm with a Ce2O3 content of 3–7%. The positive influence of the temperature factor basicity of slags and the content of cerium oxide on the process of its reduction is qualitatively explained from the standpoint of the formation of the phase composition of the slags of the studied oxide system and the thermodynamics of chemical reactions of reduction of cerium with aluminum dissolved in the metal, as well as with aluminum dissolved in the metal together with calcium carbide additives.

The influence of metal hydride hollow cathode on a Penning ion source operation has been carried out. The feature of investigation is hydrogen injection only due to its desorption from metal hydride under ion-stimulated processes. The regimes of optimal discharge operation in the hollow cathode mode are determined. It has been revealed that the transition to the hollow cathode mode occurs at lower voltages, the discharge works without external gas supply, and the working pressure in the cell is set at the level determined by the discharge current. The supply of a negative bias to the metal hydride hollow cathode weakly affects the features of the emission of axial particles, although it allows the increase of plasma density near the metal hydride hollow cathode.

The results of applying the methods of scanning electron microscopy and electron-probe microanalysis (SEM–EPMA) in combination with etching of the surface of the microparticles with an ion beam to study the composition and internal structure of single microparticles of uranium tetrafluoride are presented. It is shown that the accuracy of analysis of relief samples can be significantly improved if their relief is preliminarily smoothed by an ion beam. The standard deviation in determining the uranium weight content in microparticles of uranium tetrafluoride after smoothing of their surface with an ion beam decreases from (6.1–8.7) to (1.3–2.7)%.

The paper describes a method of negative hydrogen ions separation from axial flow of charged particles extracted from Penning discharge with a metal hydride cathode. For this purpose, an electromagnetic filter has been designed basing on numerical solution of motion equations of charged particles in the filter. The optimal parameters of the filter operation were determined for the effective registration of negative hydrogen ions extracted in axial direction. Performed calculations together with experimental verification shows that there are not more than 10% electrons in the registered H– current. This model could be applied for the interpretation of any experiments with H– ions separation from an axial flow of charged particles extracted from a source with cylindrical geometry.

The possibility of increasing the current of negative hydrogen ions extracted in the longitudinal direction from a Penning discharge with a metal hydride cathode by reducing the anode-cathode distance is shown. The features of Н– ions emission have been revealed depending on the electric shift on the metal hydride cathode and the external magnetic field. The power parameters of the electromagnetic filter have been optimized for the separation of negative ions from the extracted flux of charged particles. The current of H– ion beam was obtained at the level of 16 μA with hydrogen supply only from the metal hydride cathode and at the level of 0.1 mA at external supply from the balloon.

Sputtering yields and their angular dependences for tungsten bombarded with beryllium (Be) and neon (Ne) ions were calculated using the molecular dynamics method, showing good agreement with experiment for Ne–W collisions. Data for the Be–W interaction are necessary for calculating the impurity supply during bombardment of the diverter material (W) into plasma of the ITER tokamak. A model is proposed that explains universal behavior of the sputtering yields of tungsten in the near-threshold region during bombardment by light ions.

Thermodynamic modeling results of lanthanum equilibrium content in metal under the slag of CaO–SiO2–La2О3–Al2O3–MgO system corresponding to the chemical composition of 16 points of local simplex plan are presented using the HSC 8.03 Chemistry (Outokumpu) software package in combination with the simplex planning lattice method. In the work, slag is represented by CaO–SiO2–La2O3–15% Al2O3–8% MgO oxide system in a wide range of chemical composition for temperatures of 1550 and 1650°C, and metal contains 0.06% C, 0.25% Si, 0.05% Al (in this expression and hereinafter in mas. %). The mathematical modeling results are shown graphically in the form of composition–equilibrium content diagrams of lanthanum. There is a significant effect of slag basicity on the lanthanum equilibrium content in metal. An increase in slag basicity from 2 to 5 at a temperature of 1550°C leads to an increase in the lanthanum equilibrium content from 0.2 ppm in the region of lanthanum oxide concentration of 1–5% to 7 ppm in the region of increased concentration of lanthanum oxide to 4–7%. Hence, the increase in slag basicity favorably affects the development of lanthanum reduction. Increase in metal temperature also has positive effect on lanthanum reduction process. As temperature rises to 1650°C, the lanthanum equilibrium content in metal increases from 0.2 ppm in the region of lanthanum oxide concentration of 1–3% to 12 ppm in the region of increased concentration of lanthanum oxide to 4–7%. In diagrams of chemical composition of slag containing 56–61% CaO, 12–14% SiO2 and 4–7% La2O3 the lanthanum content in metal at level of 7–12 ppm is ensured in temperature range from 1550 to 1650°C. Therefore, a decisive role of slag basicity is confirmed, as well as the concentration of lanthanum oxide and temperature factor into the development of lanthanum reduction from slags of the studied oxide system by aluminum dissolved in metal.

The effect of annealing thermally reduced graphite oxide powders on their electrical conductivity and density at pressures up to 7 MPa is considered. The specific surface area of ​​the powders is determined at various temperatures of annealing. The complex permittivity of epoxy composites based on these powders used as fillers is measured at frequencies of 1.7, 2.9, and 9.8 GHz. The obtained average value of the dielectric loss tangent of the investigated composites in the specified frequency range exceeded the corresponding average value for epoxy composites based on natural graphite by 5–6 times.

Plasmonic biosensing has emerged as the most sensitive label-free technique to detect various molecular species in solutions and has already proved crucial in drug discovery, food safety and studies of bio-reactions. This technique relies on surface plasmon resonances in ~50 nm metallic films and the possibility to functionalize the surface of the metal in order to achieve selectivity. At the same time, most metals corrode in bio-solutions, which reduces the quality factor and darkness of plasmonic resonances and thus the sensitivity. Furthermore, functionalization itself might have a detrimental effect on the quality of the surface, also reducing sensitivity. Here we demonstrate that the use of graphene and other layered materials for passivation and functionalization broadens the range of metals which can be used for plasmonic biosensing and increases the sensitivity by 3-4 orders of magnitude, as it guarantees stability of a metal in liquid and preserves the plasmonic resonances under biofunctionalization. We use this approach to detect low molecular weight HT-2 toxins (crucial for food safety), achieving phase sensitivity~0.5 fg/mL, three orders of magnitude higher than previously reported. This proves that layered materials provide a new platform for surface plasmon resonance biosensing, paving the way for compact biosensors for point of care testing.

Under conditions of converter shop of JSC “ArcelorMittal Temirtau”, the authors have developed and implemented the direct microalloying technology of structural steels with boron. Microalloying was carried out due to boron recovery from the slags of the CaO–SiO2–B2O3–MgO–Al2O3 system formed in ladle furnaces. The use of the developed technology was provided in steels 08KP, 3SP, 3PS and 09G2S boron content of 0.0016–0.0050%, with a sufficiently high degree of metal desulfurization 36.8–51.7% and reduction in manganese ferroalloys consumption by 0.3–0.6 kg/t of steel, which improved the environmental situation by eliminating the use of fluorspar. For 09G2S steel, the yield σy and tensile σt strengths are higher for the experimental metal then for the steel without boron by an average 27 and 24 MPa, respectively. The elongation percentage of the metal with boron increased by an average 0.2%. The grain-size index of rolled metal of 08KP steel with a thickness of 2.0–2.5 mm, containing 0.001% of boron and a manganese concentration lowered to 0.18%, reaches 10.0 in contrast to 9.0 for the heats of the current production. The yield σy and tensile σt strengths are on average by 6.0 and 5.0 MPa higher for an experimental metal than for a comparative one. The percentage of elongation δ reaches 36.3% for the experimental metal unlike 33.3% for the heats of the current production. Experimental rolled metal of 3PС steel with lower concentration of manganese lowered by 0.02%, as well as with an average boron content of 0.001%, is characterized by an increased yield strength σy, tensile strength σt (on average by 2.0 and 9.0 MPa) and percentage of elongation δ reaching an average of 21.0% with fine-grained structure. The rolled metal of 3SP steel, microalloyed with boron and with a 4-mm thickness that contains manganese content reduced to 0.43%, is characterized by improved strength properties with preservation of plastic characteristics. The absolute value of the yield σy and tensile σt strengths of steel are by 4.0 and 2.0 MPa higher than the strength characteristics of steel without boron.

The nuclear stopping power of hydrogen and helium isotopes in Be, C, and W materials that are promising for use as the first wall of a tokamak reactor are calculated. It is shown that the presence of an attracting potential well has a substantial effect on the dependence of the nuclear stopping power on the collision energy. The use of potentials calculated in the approximation of the density functional theory with an attracting potential well has allowed us to obtain more accurate values of the nuclear stopping power for hydrogen isotopes, which differ by 27–60% from the tabular data at low energies. The results for different hydrogen isotopes are well described by a universal curve.

To ensure a low content of sulfur in steel, desulphurization of it in steel ladles is used. To form liquid-movable high-basicity slags with high refining properties, boron oxide is often used instead of fluorspar, the effect of which on the resistance of the refractory lining of steel ladles has not been sufficiently studied and requires detailed theoretical and experimental studies. Results of experimental studies of the influence of the basicity and content of boron oxide in the slags of the CaO-SiO 2 -B 2 O 3 -Al 2 O 3 system on periclase-carbon refractories solubility presented. The studies were carried out using the simplex-lattice planning method. The results of mathematical modeling are presented in the form of a composition-property diagram (solubility of periclase-carbon refractories). Analysis of the experimental data shown in the diagram provided new information about the influence of basicity and boron oxide content in the slags of the CaO-SiO 2 -B 2 O 3 system containing 15% Al2O3 on the solubility of periclase-carbon refractories. It was found that slags formed in the basicity region 2-3, containing 4-6% B 2 O 3 , affect quite aggressively the periclase-carbon refractories. The degree of wear of the refractory sample varies within limits from 20 to 40%. A decrease in the content of B 2 O 3 in the slag down to 1-4% with the same basicity is accompanied by a decrease of the wear degree of the periclase-carbon refractory down to 30% max. Slags of basicity 3-4 at 1-4% B 2 O 3 are characterized by a relatively low aggressive slag effect on the periclase-carbon refractory. The wear degree of periclase-carbon refractory is reduced to 8-12% and practically does not reach 15%. The displacement of slags basicity to the area of increased basicity up to 5 does not lead to a significant reduction in the aggressive impact of slag on the refractory. The degree of wear of the refractory sample varies within 6-10% at the content of 1-4%B 2 O 3 and increases to 12% at 4-6 % B 2 O 3 .

The results of basic studies of the physicochemical properties of slags are used as the basis for developing the rational composition of main magnesian slags and the process techniques for their formation by the periods of blowing a basic oxygen furnace (BOF) bath and the periods of smelting in electric arc furnaces (EAFs). The record-breaking durability of furnace linings is ensured by implementing, in the furnace shop of OJSC EVRAZ NTMK, the developed set of process techniques of forming magnesian slags in the main period of blowing and a wear-resistant skull based on the final magnesian slags. These slags produce a low aggressive effect on the lining of furnaces, while maintaining high refining properties. The furnaces’ lining durability exceeds 7000 heats; that said, the high process and key performance indicators of the process are maintained. The treatment of low manganese cast irons in the 350-ton heavy furnaces of OJSC EVRAZ ZSMK under magnesian slags allows studying the features of slag formation and changes in the chemical composition of the slag by the BOF bath blowing periods. In the course of treating phosphorous cast irons in the 300-ton BOFs at JSC ArcelorMittal Temirtau, a set of process techniques is developed for forming the magnesian slags of the recommended chemical composition by the periods of phosphorus cast iron blowing and wear-resistant skulls based on moderate-basicity final magnesian slags. The implementation of the developed process techniques ensures the lining stability of BOFs for more than 5000 heatings while maintaining the high process parameters and key performance indicators of the phosphorous treatment phase. The technology of forming rationally composed magnesian slags by the periods of smelting in EAF-135 is developed in the EAF shop of PJSC Seversky Pipe Plant. The adoption of the technology ensures the record-breaking resistance of the refractory lining of the furnace for up to 1900 heats per campaign and the high process parameters and key performance indicators of the process.

The reflection coefficients were calculated for the scattering of hydrogen isotopes and helium atoms from the surface of amorphous beryllium, carbon, and tungsten targets, which are of interest in the physics of thermonuclear plasma. The results demonstrate good agreement with the available experimental data. The isotope effect in the reflection of particles from the wall was analyzed. For the reflection of He atoms, a similarity in reflection coefficient versus Lindhard parameter curves was observed.

Simulation of the thermal processes in the turning of metals is considered. The proposed model assesses the thermal energy in the tool–workpiece contact zone, taking account of the power of the irreversible transformations. The influence of irreversible transformations on the thermal energy in the tool–workpiece contact zone is described by a model with a hereditary aspect. That may be attributed to the dissipation of thermal energy in the workpiece. Feedback in the model takes account of the influence of the temperature in the cutting zone on the reactive forces in shaping motion of the tool. The results show that such feedback plays a significant role in stabilization of the cutting process.

Objective. The influence of solid-phase reactions in the agglomerated charge layer on the quality of manganese ag-glomerate is considered. Research methodology. Thermodynamic analysis was used to establish the predominance of reactions. The phase (mineral) composition of manganese concentrates and the experimental agglomerate was investigated by X-ray diffraction method on a DRON-2 diffractometer in monochromatic Cuα radiation. The interplanar distances at the corresponding values of the X-ray reflection intensity from the investigated samples of concentrates and agglomerate were determined by comparing the obtained data with the corresponding tabular data given in the reference books on X-ray diffraction analysis of substances. Sintering of the experimental agglomerate was performed on a laboratory agglomeration bowl. Research results. It is established that the dissociation of higher manganese oxides begins at relatively low temperatures and proceeds in stages to the formation of MnO. Since the chemical affinity of manganese for oxygen is significant, reduction to metallic Mn was not observed, as this requires a high content of reducing agent and a reducing atmosphere, which is difficult to achieve in real agglomeration processes. Dissociation of rhodochrosite carbonate concentrate and gradual dissociation of dolomitized limestone leads to an increase in CO2 content in the atmosphere. Slag bonds are represented by compounds Mn2SiO4, MnO • Al2O3, Mg2SiO4, CaO • MgO • SiO2, 2CaO • SiO2. Thermodynamic calculations show that at moderate temperatures, compounds such as calcium ferrites are not formed, which is likely for the interaction between basic flux oxides and manganese oxides. Scientific novelty. Studies have shown that CaO does not completely convert to a slag bond, and even with a basicity of order 1, there is undigested lime. White spots are formed in the structure of the finished agglomerate. Such an agglomerate during transportation and storage loses strength and a large amount of trifles is formed..

Results of theoretical and experimental studies of the physicochemical properties of slags of the CaO–SiO2–B2O3 system containing 15% Al2O3 and 8% MgO lie at the basis for the development of technology for exhaustive desulfurization of metal beneath basic boron-containing slags formed in a steelpouring ladle in a ladle-furnace unit (LFU), and steel direct microalloying with boron. Methods of simplex lattice planning of an experiment, a software complex HSC 6.1 Chemistry (Outokumpu), and the method of electro-vibration viscosimetry are used. Results of thermodynamic modeling of the effect of slag basicity and B2O3 content on sulfur and boron equilibrium distribution coefficient between slag of the oxide system under study and low-carbon metal are presented. The quantitative effect of basicity and B2O3 content on slag viscosity containing 15% Al2O3 and 8% MgO at a temperature of 1600°C and the influence of the slag chemical composition of the oxide system under study on the degree of wear of periclase-carbon refractory material are shown. Results of studying physicochemical properties of slags of the CaO–SiO2–B2O3 system containing 15% Al2O3 and 8% MgO are a basis for developing a ladle slag composition with low viscosity and providing exhaustive metal desulfurization, and direct microalloying of boron steel with low corrosive effect on periclase-carbon refractories. Development of this technology provides, depending on the steel grade, a boron content of 0.001–0.008%, low metal sulfur concentration at 0.004–0.014%, a reduction in manganese ferroalloy consumption from 0.5 kg/ton of steel 08KP to 1.4 kg/ton of steel 09G2S, exclusion of ferroboron and fluorspar additives in the ladle, and achievement of good finished metal product mechanical properties.

The ranges of H and D ions in crystalline Si and W have been calculated. It is shown that the depth distribution of the ranges is divided into two components with an increase in the ion energy: one is related to the atomic scattering in surface layers, while the other characterizes particles captured into the channel. A new phenomenon has been observed: a stable spatial structure of the beam component captured into the channel is formed when particles propagate for a short distance. At ion deceleration, the particles pass to neighboring channels and the spatial structure of the beam of particles captured into the channel breaks near the stop point. A schematic of the experiment is proposed, which makes it possible to relate the obtained spatial distribution and the angular distributions of the escaped particles.

The dependence of the reflection coefficient on the form of the atom—surface interaction potential for the D—W system was found. Potentials with different potential well depths were considered. Calculations were carried out by simulating projectile trajectories and in the binary collision approximation.

We have obtained the range distributions for H, D, and He atoms within an energy range of 0.1–100 keV in amorphous W and Si for the normal incidence of bombarding particles. Calculations have been performed both in the binary collision approximation and by a more accurate method of calculating particle trajectories. It is shown that the results of both methods are in good agreement with each other and with experimental data on the mean ranges for the H–Si system. The influence of the attracting well in the particle–solid interaction potential on the results of calculations is estimated.

Genome-wide association studies have identified the CDC7-TGFBR3 intergenic region on chromosome 1 to be strongly associated with optic disc area size. The mechanism of its function remained unclear until new data on eQTL markers emerged from the Genotype-Tissue Expression project. The target region was found to contain a strong silencer of the distal (800 kb) Transcription Factor (TF) gene GFI1 (Growth Factor Independent Transcription Repressor 1) specifically in neuroendocrine cells (pituitary gland). GFI1 has also been reported to be involved in the development of sensory neurons and hematopoiesis. Therefore, GFI1, being a developmental gene, is likely to affect optic disc area size by altering the expression of the associated genes via long-range interactions.Distribution of haplotypes in the putative enhancer region has been assessed using the data on four continental supergroups generated by the 1000 Genomes Project. The East Asian (EAS) populations were shown to manifest a highly homogenous unimodal haplotype distribution pattern within the region with the major haplotype occurring with the frequency of 0.9. Another European specific haplotype was observed with the frequency of 0.21. The major haplotype appears to be involved in silencing GFI1repressor gene expression, which might be the cause of increased optic disc area characteristic of the EAS populations. The enhancer/eQTL region overlaps AluJo element, which implies that this particular regulatory element is primate-specific and confined to few tissues.Population specific distribution of GFI1 enhancer alleles may predispose certain ethnic groups to glaucoma.

Membranes that selectively filter for both anions and cations are central to technological applications from clean energy generation to desalination devices. 2D materials have immense potential as these ion-selective membranes due to their thinness, mechanical strength, and tunable surface chemistry; however, currently, only cation-selective membranes have been reported. Here we demonstrate the controllable cation and anion selectivity of both monolayer graphene and hexagonal boron nitride. In particular, we measure the ionic current through membranes grown by chemical vapor deposition containing well-known defects inherent to scalably produced and wet-transferred 2D materials. We observe a striking change from cation selectivity with monovalent ions to anion selectivity by controlling the concentration of multivalent ions and inducing charge inversion on the 2D membrane. Furthermore, we find good agreement between our experimental data and theoretical predictions from the Goldman-Hodgkin-Katz equation and use this model to extract selectivity ratios. These tunable selective membranes conduct up to 500 anions for each cation and thus show potential for osmotic power generation.

Herein, we reveal for the first time a comprehensive mechanism of poorly investigated electrochemical decomposition of CH3NH3PbI3 using a set of microscopy techniques (optical, AFM, PL) and ToF-SIM...

Particle reflection coefficients for scattering of hydrogen and deuterium atoms from amorphous beryllium, carbon and tungsten were obtained, which are of interest for thermonuclear reactor physics. For the case of deuterium scattering from tungsten the data were also calculated for polycrystalline and crystalline target. The calculations were carried out by two methods: by modeling the trajectories of the incident particles and by using the binary collision approximation. Interaction potentials between hydrogen and helium atoms and the selected materials were calculated in the scope of the density function theory using program DMol for choosing wave functions. The dependence of the reflection coefficient RN on the potential well depth was found. The results demonstrate a good agreement with the available experimental values.

Актуальність. Розмір частинок діючої речовини в лікарському засобі суттєво впливає на його розчинність, біодоступність і терапевтичну ефективність, тому дослідження показника «Розмір часток» є обов’язковим елементом фармацевтичної розробки.Мета роботи. Дослідження розміру та форми частинок лізиноприлу дигідрату та кожної допоміжної речовини для отримання оптимальних фармакотехнологічних властивостей маси для таблетування.Матеріали та методи. Об’єктами дослідження є лізиноприлу дигідрат, допоміжні речовини, отримана таблеткова маса, зразки експериментальної серії та препарат порівняння. Дослідження з визначення розміру частинок діючої речовини лізиноприлу дигідрату та допоміжних речовин проводили фармакопейними методами, такими як оптична мікроскопія (2.9.37), ситовий аналіз (2.9.12) та метод лазерної дифракції (2.9.31). Оцінку обраного складу проводили фармакотехнологічними випробуваннями згідно з ДФУ.Результати та їх обговорення. Отримані результати досліджень розміру, форми часток та фракційного складу лізиноприлу дигідрату та кожної допоміжної речовини. Визначили технологію виробництва таблеткової маси та на підставі експериментально визначених фармакотехнологічних властивостей речовин розроблено оптимальний склад таблеткової маси.Висновки. Отримані подібні результати порівняльних досліджень фармакотехнологічних властивостей дослідної серії таблеток з лізиноприлу дигідратом, 10 мг та лікарським засобом Лізиноприл-Ратіофарм, 10 мг підтверджують доцільність визначення та стандартизацію показника розмір та форма частинок для діючих та допоміжних речовин при створенні твердих лікарських форм., Topicality. The particle size of the active substance in medical product significantly affects its solubility, bioavailability, and therapeutic performance that is why the study of the “Particle size” index is compulsory for pharmaceutical development.Aim. Study of the size and shape of lisinopril dihydrate particles and auxiliary substances in order to obtain optimal pharmaceutical – technological properties of tablet mass.Materials and methods. The objects of study are lisinopril dihydrate, excipients, the obtained tablet mass, the samples of experimental series and the reference drug. Studies on the particle size determination of the active substance lisinopril dihydrate and excipients were performed by pharmacopoeial methods, such as optical microscopy (2.9.37), sieve analysis (2.9.12) and laser diffraction (2.9.31). The evaluation of the selected composition was carried out by pharmaceutical-technological tests according to SPhU.Results and discussion. The results of size examination, form of particles as well as fractional composition of lisinopril dihydrate and each of the auxiliary agents were obtained. The technology of tablet mass production was determined and on the basis of experimentally determined pharmaco-technological properties of substances, such as tapped density before and after package, flow property, the optimal composition of the tablet mass with lisinopril dihydrate was developed.Conclusions. In the result of comparative study of the pharmacological properties of the experimental series of tablets with lisinopril dihydrate, 10 mg and medical product Lizinopril-Ratiopharm, 10 mg, we confirmed the practicability of determining and standardizing the index size and shape of particles for active and auxiliary substances in the formation of solids., Актуальность. Размер частиц действующего вещества в лекарственном средстве существенно влияет на его растворимость, биодоступность и терапевтическую эффективность, поэтому исследование показателя «Размер частиц» является обязательным элементом фармацевтической разработки.Цель работы. Исследование размера и формы частиц лизиноприла дигидрата и каждого вспомогательного вещества для получения оптимальных фармакотехнологических свойств массы для таблетирования.Материалы и методы. Объектами исследования являются лизиноприла дигидрат, вспомогательные вещества, полученная таблеточная масса, образцы экспериментальной серии и препарат сравнения. Исследования по определению размера частиц действующего вещества лизиноприла дигидрата и вспомогательных веществ проводились фармакопейными методами, такими как оптическая микроскопия (2.9.37), ситовый анализ (2.9.12) и лазерная дифракция (2.9.31). Оценка выбранной композиции проводилась путем проведения фармакотехнологических испытаний по ГФУ.Результаты и их обсуждение. Получены результаты исследований размера, формы частиц и фракционного состава лизиноприла дигидрата и каждого вспомогательного вещества. Определили технологию производства таблеточной массы и на основании экспериментально определенных фармакотехнологических свойств веществ разработан оптимальный состав таблеточной массы.Выводы. Полученные подобные результаты сравнительных исследований фармакотехнологических свойств исследовательской серии таблеток с лизиноприлу дигидратом, 10 мг и лекарственным средством Лизиноприл Ратиофарм, 10 мг подтверждают целесообразность определения и стандартизации показателя размер и форма частиц для действующих и вспомогательных веществ при создании твердых лекарственных форм.

Influence of the chemical composition of CaO – SiO2 – B2O3 oxide system containing 15 % Al2O3 and 8 % MgO (in this expression and hereinafter indicated by mass %) on viscosity and crystallization temperature was studied using experiment method of simplex lattice planning. Addition of B2O3 to the slags of oxide system expands the range of slags composition with a low crystallization temperature and viscosity. Slags with a basicity of 2 – 3, containing 1 – 3 % of B2O3 are characterized by a low crystallization temperature, varying from 1400 to 1450 °С and have high flowability. The viscosity of such slags when heated to 1550 and 1600 °C does not exceed 0.20 and 0.15 Pa·s, respectively. An increase in B2O3 content to 4 – 6 % in slags with a basicity of 2 – 3 is accompanied by a decrease in crystallization temperature to 1350 – 1425 °C with keeping low, not more than 0.15 Pa·s, viscosity in the range of heating temperatures at 1550 and 1600 °C. The displacement of formed slags containing 1 – 6 % of B2O3 to the area of increased basicity up to 3 – 5 preserves their relatively high fluidity. In this case, with an increase in B2O3 concentration, there is a clear tendency for the studied oxide system to shift to the region of low crystallization temperatures. Crystallization temperature of slags with basicity of 3 – 4 containing 6 % of B2O3 reaches 1400 °С and practically does not exceed 1475 °С of slags with basicity of 4 – 5 containing 1 – 2 % of B2O3 . At temperature of 1600 °C, the viscosity of such slags varies from 0.15 Pa·s with a basicity of 3 and a content of 5 – 6 % of B2O3 to 0.25 Pa·s in the basicity range of 4 – 5 with B2O3 content of 1 – 3 %. A decrease in temperature of the studied oxide system by 50 °C is accompanied by a slight (no more than 0.05 Pa·s) increase in viscosity.

The polarization and gravimetric investigations of the anodic behavior of brass in phosphate-butanol solutions have been carried out. It was shown that the addition of butyl alcohol to the phosphate electrolyte conditions the origination of the effect of electrochemical polishing. The polarization dependencies of the brass anode in the electrolytes containing butanol are peculiar for the metals prone to the passive state transition. The sections of polarization dependences correspond to active dissolution domain, the active-passive state domain, passive brass state domain and the domain of a joint progress of the process of alloy dissolution and oxygen release. The obtained experimental data show the reasonability of the addition of butanol to the phosphate electrolyte to obtain a high quality brilliant metal surface.

Funder: H2020 Marie Skłodowska-Curie Actions; doi: https://doi.org/10.13039/100010665, Hexagonal boron nitride (h-BN) is well-established as a requisite support, encapsulant and barrier for 2D material technologies, but also recently as an active material for applications ranging from hyperbolic metasurfaces to room temperature single-photon sources. Cost-effective, scalable and high quality growth techniques for h-BN layers are critically required. We utilise widely-available iron foils for the catalytic chemical vapour deposition (CVD) of h BN and report on the significant role of bulk dissolved species in h-BN CVD, and specifically, the balance between dissolved oxygen and carbon. A simple pre-growth conditioning step of the iron foils enables us to tailor an error-tolerant scalable CVD process to give exceptionally large h-BN monolayer domains. We also develop a facile method for the improved transfer of as-grown h-BN away from the iron surface by means of the controlled humidity oxidation and subsequent rapid etching of a thin interfacial iron oxide; thus, avoiding the impurities from the bulk of the foil. We demonstrate wafer-scale (2 inch) production and utilise this h-BN as a protective layer for graphene towards integrated (opto) electronic device fabrication., European Union's Horizon 2020 research and innovation program under Grant Agreement No number 785219. European Union's Horizon 2020 research and innovation program under Grant Agreement No number 796388. the Royal Commission for the Exhibition of 1851. EU Marie Skłodowska-Curie Individual Fellowship (Global) under grant ARTIST (No. 656870). EPSRC (EP/P005152/1, and Doctoral Training Award EP/M508007/1). U.K. Department of Business, Energy and Industrial Strategy (NPL Project Number 121452).

Nonmetallic inclusions in steel such as oxides, silicates, aluminates, spinels, etc. substantially reduce the quality of metal. They are mainly introduced by the slag formed on the metal surface of a doublestrand plant. It is proposed to separate the slag from the metal using a special perforated tube installed on the refractory pocket block of the ladle bottom and fixed with gunning mix. The use of this device for continuous slab casting ensures the high quality of hot- and cold-rolled sheets.

The article presents the study of the features of the gas-liquid system of the column apparatus: issues related to the design features of column apparatuses are considered. They allow you to increase the height of the foam layer on the mesh lattices of the apparatus, without increasing at the same time neither the load on the liquid nor the gas flow rate. Questions, related to the structural features of columnar vehicles which allow to increase the height of foamy layer on the mesh lattices of vehicles, are considered in the article, here, not increasing speed of gas stream. Developed by us a contact element has good indexes for the wide range of loadings on a liquid and gas. The methods of calculation described in the article fully confirm experimental researches and well correlate with the before conducted researches

The simplex lattice method has been applied to studying the chemical composition influence of CaO–SiO2–B2O3 oxide system containing 15% Al2O3 and 8% MgO on viscosity and solidification point (hereinafter wt % are used). The addition of boron oxide to slags of the considered oxide system expands the range of slag composition with low solidification point and viscosity. The slags with basicity of 2.0–3.0 containing 1– 3% B2O3 are characterized by low (1400–1450°C) solidification point and high viscosity. Viscosity of such slags upon their heating to 1550 and 1600°C does not exceed 0.20 and 0.15 Pa s, respectively. An increase in B2O3 content to 4–6% in slags with basicity of 2.0–3.0 is accompanied by a decrease in solidification point to 1350–1425°C with retention of low (not higher than 0.15 Pa s) viscosity at heating temperature of 1550 and 1600°C. Generated slag displacement containing 1–6% B2O3 to the basicity regions increasing to 3.0–5.0 retains a sufficiently high fluidity. Herewith, it can be observed that the considered oxide system is displaced to a low solidification point region with an increase in boron oxide concentration. A slag solidification point with basicity of 3.0–4.0 containing 6% B2O3 reaches 1400°C and actually does not exceed 1475°C for the slags with basicity of 4.0–5.0 containing 1–2% B2O3. At 1600°C, the slag viscosity varies from 0.15 Pa s at basicity of 3.0 and B2O3 content of 5– 6% to 0.25 Pa s at basicity of 4.0–5.0 and B2O3 content of 1–3%. A temperature decrease of the considered oxide system by 50°C is accompanied by an insignificant (not more than 0.05 Pa s) increase in viscosity.

Technology of magnesia slags forming provides increase of electric energy utilization efficiency and furnace lining resistance due to early formation of stable slag foam and decrease of aggressive slag impact on the lining. At the same time the practice of operation with magnesia slags shows, that excessive over-saturation them by magnesium oxide results in heterogenization, decrease of refining properties and deterioration of some technological, technical and economic process indices. Therefore, study and elaboration technology of rational composition magnesia slags forming by periods of a heating in EAF is an actual task. Results of numerical simulation of slag temperature and chemical composition effect on MgO saturation concentration during different melting periods in EAF presented. Besides, results of analysis of refining abilities of magnesia slags depending on MgO saturation degree also presented study of magnesia slags viscosity effect depending on MgO basicity and saturation concentration, as well as magnesia slag chemical and phase composition effect on foaming efficiency. Results of theoretical and experimental study were used as a base of elaboration rational slag composition by periods of melting in the EAF and technological techniques of their formation. A technology elaborated and implemented at PAO “Seversky pipe plant” EAF shop by leaving some amount of high-magnesia slags of the previous heat and addition in two stages high-magnesia flux of “Magma” grade during the oxidizing period. This resulted in a record resistance of the refractory EAF lining, exceeding 1900 heats within a campaign and a high level of technological, technical and economic process indices.

The quaternary reciprocal system Na,Rb||F,I,CrO4 was studied, low-melting mixtures based on which are promising as fusible electrolytes for chemical current sources, heat-storage materials, and media for growing single crystals. The system was partitioned into simplexes using graph theory, and the tree of phases of the system was constructed. The tree of phases is linear and contains four stable tetrahedra sharing stable cutting triangles. The combined stable tetrahedron NaF–RbI–RbF–Rb2CrO4 was investigated by differential thermal analysis. The crystallization surface of this stable tetrahedron is represented by the volumes of sodium fluoride, rubidium iodide, rubidium fluoride, rubidium chromate, and the compound Rb3CrO4F. Monovariant equilibrium lines meet at two quaternary invariant points: eutectic E◻491 and peritectic P◻508.

The depth distribution of the energy release (linear energy transfer) occurring upon bombardment of a tungsten target by deuterium atoms with energies ranging from 100 eV to 10 MeV is calculated. It is demonstrated that, contrary to common belief, the maximum energy release at energies below 100 keV is localized near the surface of the solid. At energies above 100 keV, the shape of the distribution changes, and a Bragg maximum emerges near the particle stopping point. The depth distribution of the energy release in tungsten under conditions typical of the ITER tokamak reactor is determined. This distribution provides an opportunity to estimate the wall heating by incident plasma atoms.

Experiments on nonstationary stimulated Raman scattering (SRS) of laser pulses and an optical breakdown are performed to study water samples with gas nanobubbles (bubstons) and without the bubston phase. The SRS excitation threshold in water with the bubston phase turns out to be higher than that in bubston-free water, and the optical breakdown threshold in bubston-containing water is lower than that in bubston-free water. The spectral composition of the SRS signal from bubston-free water samples is found to differ from that of bubston-containing water samples. This effect is caused by the formation of long-lived high-molecular H2O complexes near the bubston surface, which are stabilized by the dispersion forces acting from this surface. Since these complexes are located inside 1–2 monolayers adjacent to the surface, the volume density of these complexes is negligibly small as compared to the density of “free” (not bound to bubstons) molecules. To interpret the experimental results, we advance a hypothesis that the detected effect is related to the giant enhancement caused by the generation of a resonance plasmon inside a bubston during an optical breakdown. As follows from our estimates, the bubston-related plasma frequency falls in the range 2600–3200 cm–1; it is this range that contains the SRS spectral lines of water containing the bubston phase.

Particle trajectories are calculated to study the rainbow scattering and the focusing of Ar atoms on the Al(111) and Ag(111) crystal surfaces and Ne, Ar, and Kr atoms on the Al(001) crystal surface. The rainbow-scattering-induced features in spectra are used to determine the thermal vibration amplitudes of atoms for the Al(111) and Ag(111) targets. These data agree with the data of independent measurements. The dependence of the position of a rainbow peak on the initial energy of atoms is used to find the atom–surface interaction potentials in the energy range of 0.3–70 eV for the case Ar–Ag and 3–45 eV for other cases. The values and the functional dependences of the potentials on the internuclear distance differ strongly from the well-known pair potential models. This difference is associated with the interaction of a projectile atom with the conduction electrons in a metal.