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The aim of this work is to investigate new, relatively cheap and effective catalyst, which could be used as PP fillers in the primary production of polymer matrix composites with improved mechanical properties and, at the same time, characterized with high catalytic activity in the process of the PP-based composites recycling by the thermo-catalytic cracking. Two kinds of the protonated potassium polytitanate (PPT), having platy shape of particles and characterized with low friction coefficient and high reflectance of UV radiation, but different Ti4+/Ti3+ molar ratio, are investigated as such functional fillers. It is shown that the admixture of the PPT fillers (10 wt.%) allows obtaining the PP-matrix composites characterized with increased values of Young modulus and, especially, wear resistance, in comparison with the materials filled with talc. It is shown that the PP matrix composites containing the PPT fillers can be directly used for pyrolytic processing due to high catalytic activity in the cracking processes taking place at moderate temperatures (~ 450 °C). The chemical composition of gaseous and liquid products, obtained as a result of this processing, is investigated. Some differences in the chemical composition of the products are considered taking into account chemical and structural features of the PPT and zeolite catalysts. [ABSTRACT FROM AUTHOR]

The losses of productivity observed in gas suction within an oil-free two-rotor vacuum pump are considered. In CFD (computational fluid dynamics) modeling of pump operation, both with and without a pressure difference, the influence of heating and throttling of the gas is analyzed, as it passes through the intake tube and as it fills an isolated chamber. Experimental data confirm the modeling results. Gas heating in suction has the greatest influence on pump performance. The proposed formula determines the losses with no more than 6% error. [ABSTRACT FROM AUTHOR]

The distributions of intermediate and slow neutrons from the outlet collimated channel of a photoneutron source are measured. A significant difference is observed between the shapes of the distributions of two groups of neutrons with energies above and below the cadmium cutoff. Whereas the distribution of intermediate neutrons has a symmetrical Gaussian shape, the distribution of slow neutrons has a complex shape. The possible causes of the difference between these shapes are discussed. [ABSTRACT FROM AUTHOR]

Multiwire position-sensitive neutron detector with two layers of boron-10 has been developed to detect both thermal and fast neutrons. Sensitive dimensions of two coordinate neutron detectors are 50 × 50 mm. New detector characteristics are compared with those of a 100 × 100 mm detector built earlier which we used in neutron flux spatial distribution measurements. Plane-parallel design of the new detector has symmetrical structure with respect to wire anode and also includes two intermediate grids and two cathodes made of parallel wires with 2 mm pitch and two silicon substrates coated with boron-10 layers of 0.003 mm thickness. Detector geometry and working gas mixture and pressure are chosen so as to ensure full absorption of secondary alpha particle from reaction with thermal neutron within detector gas medium half thickness. Neutron coordinates are determined from measured ionization loss pulse heights produced by secondary nuclei. The detector expected efficiency to thermal neutrons is about 5%. The detector can be used in small-angle and diffraction scattering setups in condensed matter physics. [ABSTRACT FROM AUTHOR]

In the 1H NMR spectra (DMSO-d6) of 1,3-disubstituted ureas containing the 4,7,7-trimethyl-3-oxo-4-oxabicyclo[2.2.1]heptan-1-yl substituent, the signals for the CH2—CH2 moiety appear as an ADMP-type spin system consisting of four doublets of doublets of doublets with chemical shifts in the range from 1.54 to 2.80 ppm. The experiment in CD3OD showed the disappearance of the signal at δ 2.80 and a change in the multiplicity of the other signals, which is indicative of the selective deuterium exchange of one of the four protons of the CH2—CH2 group for a deuterium atom. This allows the selective modification of compounds containing the oxacamphanyl moiety. [ABSTRACT FROM AUTHOR]

In the present study, the fabrication route, including combining the aerosol deposition method and magnetron sputtering, was demonstrated for the fabrication of metal-supported solid oxide fuel cells. Thick-film anode layers (approximately 45 µm) of 10 mol.% gadolinia-doped ceria (GDC) and nickel (57/43 wt% ratio) were deposited by means of the aerosol deposition method on porous metal (Cr-28 wt%, Fe) supports from softly agglomerated submicron powders. The half-cells with the anode layers were sintered at 1000 °C in vacuum. Thin-film membranes of gadolinia-doped ceria (approximately 4 µm) were deposited by magnetron sputtering. (La0.80Sr0.20)0.95CoO3−δ (LSC) cathode layers were applied by screen printing with subsequent in situ sintering. The manufactured cells were investigated by scanning electron microscopy and electrochemical measurements. Depending on the manufacturing route and testing temperature, the cells with hydrogen as a fuel and air as an oxidant demonstrated open circuit voltages from 0.57 to 0.82 V. At 750 °C, the cell maximum power density was 0.3 W cm−2. [ABSTRACT FROM AUTHOR]

Nickel oxide reduction kinetics and formation of the electric potential of anode-supported solid oxide fuel cell (SOFC) were studied using in situ Raman spectroscopy (RS) and conventional electrochemical techniques. It was shown that the time dependence of the electric potential and the intensity of the Raman spectra during anode substrate reduction can be conditionally divided into two stages. At the initial stage, in the first seconds after hydrogen supply, the open circuit voltage (OCV) quickly rises and stabilizes at a value of about 0.85 V. This stage is not accompanied by noticeable changes in RS. Then, there is a more gradual rise, requiring tens of minutes, to the OCV equilibrium value. The beginning of the second stage of the increase in the OCV coincides with a sharp change in the intensity of the specific spectral line in the Raman spectrum. An increase of the OCV in the first seconds after hydrogen supply is explained by an increase in the hydrogen concentration at the outer boundary of the SOFC anode. The sharp change in the intensity of the Raman spectrum, in turn, can be explained by the reduction of NiO to the metallic state in the near electrolyte region. In this work, a detailed reduction model of the NiO-YSZ (yttria-stabilized zirconia) cermet composite supporting substrate of an anode-supported SOFC was constructed. The model was developed on the assumption that the rate of the nickel oxide reduction reaction at each point of the sample depends only on the partial pressure of hydrogen, the fraction of oxidized nickel, and temperature. In the case of repeated reduction and at high temperatures, it can be assumed that the reaction has first-order kinetics, i.e., reaction rate is proportional to the fraction of oxidized nickel. At primary reduction and temperatures of 400–600 °C, the reaction is described by Avrami-Erofeev kinetics. [ABSTRACT FROM AUTHOR]

A procedure has been developed for the synthesis of 3,5-difluoroadamantan-1-yl isocyanate from 3,5-difluoroadamantane-1 carboxylic acid and diphenylphosphoryl azide using a new fluorinating agent, Ishikawa reagent, in one stage of the synthesis. The reaction of 3,5-difluoroadamantan-1-yl isocyanate with aliphatic diamines and trans-4-[(4-aminocyclohexyl)oxy]benzoic acid afforded a series of N,N′-disubstituted ureas and bis-ureas in 43–96% yields. The hydrolysis of 3,5-difluoroadamantan-1-yl isocyanate in the presence of a catalytic amount of DBU gave symmetrical N,N′-bis(3,5-difluoroadamantan-1-yl)urea in 47% yield. A relation between the number of fluorine atoms in the adamantane fragment on the melting points and lipophilicities of the synthesized ureas has been revealed, which makes it possible to control these important properties of ureas as potential enzyme inhibitors. [ABSTRACT FROM AUTHOR]

The mesomorphic, optical, and dielectric properties of a nematic mixture of 4-pentyloxy- and 4-heptyloxy-4′-cyanobiphenyls doped with optically active (bis)camphoralidene-hexamethylenediamine were studied. The clearance temperatures of the mixtures were measured using polarization microscopy to assess the degree of destabilization of the mesophase upon dopant introduction. Additionally, the helical pitch of the induced chiral nematic phase in the mixtures was measured, and the influence of the chiral dopant on the mesophase's anisotropic characteristics was investigated. [ABSTRACT FROM AUTHOR]

The influence of the solution acidity on the interaction between bovine serum albumin (BSA) molecules and gold nanoparticles in solutions has been investigated by absorbance spectroscopy, fluorescence spectroscopy, and dynamic light scattering (DLS). The influence of pH on the processes of aggregation–disaggregation of gold nanoparticles with BSA and without it and on the denaturation of protein solution is demonstrated. It is also shown that BSA molecules can stabilize gold nanoparticles at acidic pH values of 2.0–4.0. The data obtained can be useful for physiologists studying the influence of nanoparticles on different biological media of the body. [ABSTRACT FROM AUTHOR]

A theoretical study of new polymorphic varieties of boron nitride, which have diamond-like structures with boron and nitrogen atoms in equivalent structural positions, was carried out. The model construction of new phases of boron nitride was performed in the process of crosslinking of precursor nanostructures. Single-walled boron nitride nanotubes with chirality indices (3;0), (4;0), and (6;0) were chosen as precursors for the model construction of diamond-like phases. Using the density functional theory method in the generalized gradient approximation, the possibility of stable existence of three new structural varieties of boron nitride with a diamond-like structure, namely, BN-TA4, BN-TA5, and BN-TA6, was established: the structure of the BN-TA7 diamond-like phase turned out to be unstable and, in the process of geometric optimization, was transformed into the initial structure, a boron nitride nanotube (6;0). As a structural characteristic, the bulk density of new polymorphs was determined to be in the range from 2.613 to 3.0836 g/cm3. The sublimation energy of new polymorphic varieties ranged from 17.16 to 17.63 eV/(BN). The value of the band gap near the Fermi energy varied from 5.37 to 5.74 eV. [ABSTRACT FROM AUTHOR]

The optimization of technology for manufacturing bilayered anode supports for planar solid oxide fuel cells (SOFCs) using precursors was performed. The bilayered anode supports for the second-generation planar SOFCs were manufactured by the tape casting method followed by the lamination. Nickel sulfate heptahydrate NiSO4∙7H2O was used to fabricate the composite material for the current-collecting layer containing 60 vol % NiO and the functional layer containing 40 vol % NiO (the chosen values are close to the first and second percolation thresholds). The 8YSZ/NiSO4 composite mixture was calcined at a temperature of 1000°C. The use of this precursor resulted in fabricating durable anode support that retains mechanical stability during redox cycling. Finely dispersed NiO in a thin functional layer led to a high density of three-phase boundaries, which had a beneficial effect on the electrochemical activity of the anode. Based on these anode supports, the model samples of solid oxide fuel cells were manufactured. The samples were studied using conventional electrochemical techniques. The power density was 1 W/cm2 at an operating temperature of 750°C. [ABSTRACT FROM AUTHOR]

Cd1 – xZnxTe crystals are required for ionizing radiation detectors, which are widely used in science, technology, medicine, and other fields. Grown-in dislocations arise and low-angle boundaries form during crystal growth due to strains caused by crystallization. A typical problem of Cd–Zn–Te ternary compounds grown from melt are tellurium inclusions, which worsen the efficiency of detector operation. Microgravity conditions provide unique opportunities for the growth of high-quality crystals on account of the lack of convection, more equilibrium mixing of the melt, and a decrease in internal stresses. Since the properties of such crystals greatly depend on the production conditions, a seed and a feed ingot are needed with predetermined composition and structure. Ampoules with two compositions of the material have been prepared for space experiments. The crystals have been grown from loads with the compositions Cd0.96Zn0.04Te and Cd0.9Zn0.1Te, each consisting of an oriented seed, a solvent, and a feeding ingot. The latter are single-phase single crystals, with a chosen orientation and low dislocation density, which comply with the requirements for the growth of CZT crystals under microgravity conditions. The ampoules with the materials have been sent to the International Space Station (ISS) for CZT crystal growth using equipment for growth already installed on board the "Nauka" module. [ABSTRACT FROM AUTHOR]

Shielding of materials from the impact of powerful plasma flows is of undoubted interest for solving a wide range of fundamental and applied problems. For example, to protect the divertor from the effects of high-temperature plasma during current interruptions in tokamaks, nitrogen or neon gas injection is used directly in front of the surface of the divertor plates. Also, using a gas screen, it is possible to regulate the thermal load on materials when they are irradiated with powerful plasma flows in order to improve the performance characteristics of surface layers. The work investigated the influence of a nitrogen gas screen on the shielding of tungsten when exposed to powerful flows of hydrogen plasma and on the localization of tungsten vapor near the surface of the irradiated target. It has been established that a gas screen of nitrogen with an atomic density of 2 × 1017 cm–3 in front of a tungsten target reduces the thermal load on the target by 2‒2.5 times less than the maximum level of energy absorbed by tungsten under pulsed action of a powerful flow of hydrogen plasma without a gas screen. The dependence of the density of energy absorbed by the target on the density of particles in the screen was experimentally determined. It is shown that, under our experimental conditions, the presence of a nitrogen gas screen in front of the target prevents the propagation of tungsten over distances of more than 1 cm along the magnetic field lines toward the incident plasma flow. [ABSTRACT FROM AUTHOR]

A series of N,N′-disubstituted ureas and bis-ureas were synthesized in 36–85% yields by the reaction 3-bromoadamantan-1-yl isocyanate with α,ω-alkanediamines, fluorinated anilines, and trans-4-[(4-aminocyclo-hexyl)oxy]benzoic acid. The hydrolysis of 3-bromoadamant-1-yl isocyanate in the presence of a catalytic amount of DBU gave 60% of symmetrical N,N′-bis(3-bromoadamantan-1-yl)urea. The synthesized compounds are promising as inhibitors of human soluble epoxide hydrolase (hsEH). [ABSTRACT FROM AUTHOR]

Plasma flows with high velocity, density, and energy are widely used in research on the interaction of plasma with materials, modeling of astrophysical processes, development of plasma thrusters and plasma radiation sources, and plasma injection into fusion devices. Electrodynamic plasma guns can be used to generate such flows. This paper describes the design features of a powerful pulsed plasma gun and diagnostic tools for measuring the parameters of the plasma flow generated by it. [ABSTRACT FROM AUTHOR]

Driven-dissipative protocols are proposed to control and create nontrivial quantum many-body correlated states. Protocols conserving the number of particles stand apart. As well-known, in quantum systems with the unitary dynamics the particle number conservation and random scattering yield diffusive behavior of two-particle excitations (diffusons and cooperons). Existence of diffusive modes in the particle-number-conserving dissipative dynamics is not well studied yet. We explicitly demonstrate the existence of diffusons in a paradigmatic model of a two-band system, with dissipative dynamics aiming to empty one fermion band and to populate the other one. The studied model is generalization of the model introduced in F. Tonielli, J.C. Budich, A. Altland, and S. Diehl, Phys. Rev. Lett. 124, 240404 (2020). We find how the diffusion coefficient depends on details of a model and the rate of dissipation. We discuss how the existence of diffusive modes complicates engineering of macroscopic many-body correlated states. [ABSTRACT FROM AUTHOR]

An efficient approach to the synthesis of (+)-camphor and (–)-fenchone anils has been developed, which involves the reaction of the corresponding bicyclic monoterpenoid ketones with substituted anilines in the presence of in situ prepared (i-PrO)2Ti(OTf)2·(i-PrOH)2 complex, as a homogeneous catalyst, and (i-PrO)4Ti, as a dehydrating agent. The advantage of the suggested method lies not only in obtaining target products in good yield and high purity, but also in a simplified procedure for their isolation. These products are of interest as potential pharmacologically active compounds, antioxidants for rubber mixtures, and components of 3D-printing formulations. [ABSTRACT FROM AUTHOR]

Results are presented of research aimed at creating a compact source of soft X-ray and vacuum ultraviolet radiation through the collision of a powerful plasma flow with a gas jet. In experiments that were carried out, a pulsed electrodynamic accelerator generated a hydrogen plasma flow with an energy constant of ≈50 kJ and duration of 10–15 μs. The flow, with a density of ≈6 × 1015 cm–3, moved at a velocity of (2‒4) × 107 cm/s in a longitudinal magnetic field with an induction of up to 2 T and interacted with a flat supersonic gas jet. The maximum molecular density of the gas, nitrogen or neon, in the jet reached 1017 cm–3. The formation of a compact emitting plasma layer with a thickness of 3–5 cm, moving along the path of the hydrogen plasma flow at a speed of approximately 3 × 106 cm/s was demonstrated. In several experiments, a tungsten plate was used as an obstacle to confine the motion of the emitting plasma along the magnetic field, localizing the interaction region between the plasma flow and the gas jet within the diagnostic control zone. Soft X-ray obscurography and spectroscopy were used to obtain data regarding the radiation generation from the interaction zone of the hydrogen plasma flow and the gas jet. The results of measuring the radiation energy from the formed plasma are presented: ≈2 kJ in the case of a nitrogen jet and ≈ 3 kJ in the case of a neon jet. Numerical modeling of the line radiation from multi-charged ions and subsequent comparison of calculated and experimental data allowed estimating the electron temperature of the nitrogen and neon plasmas formed during the interaction of the hydrogen plasma flow with the gas jet at a level of ≥40 eV. [ABSTRACT FROM AUTHOR]

A series of N,N′-disubstituted ureas containing a pyridine or quinoline fragment and a lipophilic adamantane moiety (13 examples, 53–94% yield) have been synthesized by the reaction of N,N-dimethyl-N′-(pyridin-2-yl or quinoline-2-yl)ureas with amine hydrochlorides. The synthesized compounds differed from each other by the position of substitution in the adamantane fragment, structure of the alkyl linker between the adamantane fragment and amide group, and heterocyclic substituent. They are potential target-oriented inhibitors of human soluble epoxide hydrolase (sEH). [ABSTRACT FROM AUTHOR]

The rheological properties of starch-latex blends mechanically activated in a rotary-pulse apparatus were studied. Several integral criteria—flexibility, polarity and hydrophilicity of macromolecules, particle size and electrokinetic potential—were chosen to evaluate the effectiveness of starch modification with synthetic copolymer latexes. An increase in the blends viscosity was shown to observe for more flexible polymers Binder RA, Binder AF, Ruzin with a glass transition temperature (Tg) below 25°C. Polymers BAK-R and Aquapol with high values of the modulus E′ reduce viscosity. The hydrophilicity of synthetic copolymers and their particle size promote an increase in the blends viscosity. [ABSTRACT FROM AUTHOR]

The mesomorphic, optical, dielectric, and orientation properties of nematic mixture CB-2 doped with chiral bis(camphorylidene)ethylendiamine were studied. The cleaning temperatures of mixtures were measured by polarization microscopy. The destabilization of the mesophase upon the introduction of a dopant was assessed. The helix pitch of the induced chiral nematic in mixtures was measured. The effect of a chiral dopant on the anisotropic characteristics of the mesophase was studied. [ABSTRACT FROM AUTHOR]

In this paper we study repulsion of a Néel-type skyrmion in a chiral ferromagnetic film from a superconducting Pearl vortex due to the stray fields. Taking into account an effect of the vortex magnetic field on the skyrmion non-perturbatively, we find that the repulsion between them is suppressed with increase in the dimensionless strength of the vortex magnetic field. This manifests itself in complicated evolution of the free energy with increase in the vortex magnetic field and reduction of the equilibrium distance between the centers of Néel-type skyrmion and Pearl vortex. [ABSTRACT FROM AUTHOR]

The stage-wise character of the rock destruction process has been studied with the use of indentation and acoustic emission data and the further analysis of fluctuations in the indentation force and the energy of an acoustic signal. The measured experimental results on indentation and acoustic emission data processing make it possible to establish the correspondence between the types of collective modes in the ensembles of shear defects, the damage clustering effects, and the staged character of the destruction process in a deformation site. A self-similar nature of collective modes is the basis for the interpretation of indentation data, the generalization of results to the scales of the seismic and technogenic events, and the estimation of parameters that characterize the development of a destruction site in the processes of drilling. [ABSTRACT FROM AUTHOR]

The direction of overflow in the rotary mechanism of a screw vacuum pump and the shapes of the channels through which it occurs are considered. Calculation formulas for each type of channel are given. The conductance of a triangular slot, i.e., the gap with the largest overflow, is calculated using the slope coefficient method in the COMSOL Multiphysics software. The dependence of the conductance on the screw pitch is obtained for a different assignment of the computational domain. Based on the data obtained, the mass flow coefficient was calculated, which can be used to create a mathematical model of a screw vacuum pump. [ABSTRACT FROM AUTHOR]

The paper focuses on the synthesis of gadolinium-doped ceria (CexGd1 – xO2 – y) thin films on the anodes of solid oxide fuel cells by reactive dual magnetron sputtering. CexGd1 – xO2 – y thin films 4 μm thick are deposited in the transition and oxide modes, differing by the oxygen concentration in the vacuum chamber. Residual stresses after the film deposition and thermal annealing in air are determined by the curvature of the anode plates. Dependences are obtained between the deposition modes, residual stresses and parameters of fuel cells with the CexGd1 – xO2 – y electrolyte. The surface morphology and cross-section of the films are studied on a scanning electron microscope. The X-ray diffraction analysis is additionally conducted to study the structure of gadolinium-doped ceria thin films using the synchrotron radiation during 1300°С annealing. It is shown that under certain conditions of the film deposition and annealing, compressive stresses can transfer to tensile stresses, which reduces the anode plate deformation after the CexGd1 – xO2 – y electrolyte deposition. [ABSTRACT FROM AUTHOR]

A one-step synthesis of 1-(isocyanatomethyl)-3,5-dimethyladamantane with a yield of 87% is described. The reaction of 1-(isocyanatomethyl)-3,5-dimethyladamantane with aliphatic diamines gave a series of symmetrical 1,3-disubstituted ureas with 63–99% yields. The synthesized ureas hold promise as human soluble epoxide hydrolase inhibitors. [ABSTRACT FROM AUTHOR]

The results of 70 cycles of rigorous testing for resistance to thermal cycling of the medium are presented – temperature reduction of the supplied water δTin.30 sec = 262°C over the first 30 sec of the process for two check valves of the type S23307-0160-65, DN 65 (body material St12Kh18N10T) as well as four of the same thermal cycles for a bellows-type stop valve S.KZSA-100-00-00-E-03, DN100 (body material St20). Sealing gaskets containing thermally expanded graphite are installed in the body–cap connector of all valves. At the completion of the tests, all three types of gaskets retained their integrity and serviceability. However, if the stop valve DN100, which structurally has an axisymmetric temperature distribution of the metal in the above-flow part of the body, retained its tightness throughout all thermal cycles, then out of 140 thermal cycles the check valves DN65, which do not have such an axisymmetric temperature distribution dynamics, had 18 brief (40–50 sec) weak seal failures in the front portion of the valve connector. The average difference of the temperature of the metal above the flow portion of the valve body in the front and back sectors was estimated as ΔTav ~ 40°C in the presence of seal failure. [ABSTRACT FROM AUTHOR]

We have developed an improved two-stage approach to the synthesis of 2-fluorophenylisoselenocyanate from 2-fluoroaniline, which at the first stage uses a mixture of solvents, dichloromethane and tert-butanol, allowing us to significantly simplify the isolation and purification of the target product. The reaction of 2-fluorophenylisoselenocyanate with adamantyl-containing and bicyclic amines gave 1,3-disubstituted selenoureas in 27–83% yields. The obtained selenoureas were studied for their antioxidant properties and antiradical activity. A number of compounds demonstrated the antioxidant properties several times exceeding the values of the reference Trolox and Ionol. [ABSTRACT FROM AUTHOR]

A series of N,N′-disubstituted bis-ureas containing a lipophilic 4-(trifluoromethoxy)phenyl fragment were synthesized in 58–80% yields by reaction of 4-(trifluoromethoxy)phenyl isocyanate with aliphatic diamines. The synthesized compounds are promising as inhibitors of human soluble epoxide hydrolase. [ABSTRACT FROM AUTHOR]

A series of N,N′-(alkane-α,ω-diyl)bis[N′-(adamantan-1-yl)selenoureas] have been synthesized in 27–84% yields by the reaction of adamantan-1-yl isoselenocyanate with alkane-α,ω-diamines. The synthesized compounds melted in the range 105–164°C, which is lower by ~80°C than the melting point range of their isosteric analogs containing urea fragments. N,N′-(Alkane-α,ω-diyl)bis[N′-(adamantan-1-yl)selenoureas] are promising as inhibitors of human soluble epoxide hydrolase. [ABSTRACT FROM AUTHOR]

The interplay of Anderson localization and electron–electron interactions is known to lead to enhancement of superconductivity due to multifractality of electron wave functions. We develop the theory of multifractally enhanced superconducting states in two-dimensional systems in the presence of spin–orbit coupling. Using the Finkel'stein nonlinear sigma model, we derive the modified Usadel and gap equations that take into account renormalizations caused by the interplay of disorder and interactions. Multifractal correlations induce energy dependence of the superconducting spectral gap. We determine the superconducting transition temperature and the superconducting spectral gap in the case of Ising and strong spin orbit couplings. In the latter case the energy dependence of superconducting spectral gap is convex whereas in the former case (as well as in the absence of spin–orbit coupling) it is concave. Multifractality enhances not only the transition temperature but, in the same way, the spectral gap at zero temperature. Also we study mesoscopic fluctuations of the local density of states in the superconducting state. Similarly to the case of normal metal, spin–orbit coupling reduce the amplitude of fluctuations. [ABSTRACT FROM AUTHOR]

A three-stage method for the preparation of 3-fluoro-1-isocyanatoadamantane in 76% yield was developed using the reaction of 3-hydroxyadamantane-1-carboxylic acid with Ishikawa's reagent and subsequent reaction with diphenylphosphoryl azide. The reaction of 3-fluoro-1-isocyanatoadamantane with a number of aliphatic diamines, fluorine-containing anilines, and trans-4-amino(cyclohexyloxy)benzoic acid afforded a new series of targeted inhibitors of epoxide hydrolase sEH in 43–89% yields. The absence of a methylene bridge between the adamantane and urea moieties led to an increase in the melting points of the synthesized compounds, while the introduction of a fluorine atom reduces their melting points compared to nonfluorinated analogs. [ABSTRACT FROM AUTHOR]

Molecular and crystal structures of five substituted urea derivatives with bulky adamantyl fragments in their substituents are considered. It is shown that the crystals of these compounds are formed by a system of intermolecular hydrogen bonds. The molecules without proton-donor groups in the lateral substituents form a linear system of N–H⋯O hydrogen bonds involving only the amide functional group, while the urea molecules containing proton-donor groups or the crystal solvates with proton-donor solvate molecules exhibit more complex motifs of hydrogen bonds. [ABSTRACT FROM AUTHOR]

A method of 106Ru deposition on a concave metal surface of an ophthalmic applicator substrate is reported, which consists in preparing the substrate surface by coating it with a layer of silver, producing a solution of 106Ru in glycerol with the required volumetric activity, filling the substrate with the solution, and evaporating the solution. Deposition by the reported method makes it possible to produce 106Ru layer uniformly distributed and strongly bonded to the surface on the substrate surface. [ABSTRACT FROM AUTHOR]

We present the results of an experimental study of multiple scattering of positively charged high-energy particles in bent samples of monocrystalline silicon. This work confirms the recently discovered effect of a strong reduction in the rms multiple scattering angle of particles channeled in the silicon (111) plane. The effect is observed in the plane orthogonal to the bending plane. We show in detail the influence of angular constraints on the magnitude of the effect. Comparison of the multiple scattering process at different energies indicates a violation of the law of inverse proportionality of the rms angle of channeled particles with energy. By increasing the statistics, we have improved the results of multiple scattering measurements for particles moving, but not channeled, in silicon crystals. [ABSTRACT FROM AUTHOR]

The article analyzes the prospects for using the IR-Fourier methods of spectroscopy and multidimensional analysis for identification and gradation in the composition of granulated domain slags of major Russian manufacturers. The characteristic absorption bands corresponding to the content in the composition of calcites, silicates, aluminosilicates are revealed. The principal component method identified the characteristic absorption bands of the slag spectra that contributed most to the gradation of the samples depending on their chemical composition. Generalized recommendations for choosing the scope of granulated domain slags are formulated. A generalized method of using optical spectroscopy and multidimensional analysis for identifying and classifying mineral raw materials is given using domain metallurgical slag as an example. [ABSTRACT FROM AUTHOR]

The phase, elemental, and particle-size distributions and the morphology of a dust sample from electric steel-smelting production were studied. The heat-treatment temperature of the sample in a reducing atmosphere at which the greatest weight loss occurred was determined by thermogravimetric analysis. The elemental and phase compositions of the reduced sample were determined. The effect of the processing temperature regime on the degree of zinc removal from the sample was shown. [ABSTRACT FROM AUTHOR]

The bilayered supports for anode-supported solid oxide fuel cells (SOFCs) based on composites of NiO and ZrO2 stabilized by 10 mol % Sc2O3 and 1 mol % Y2O3 (10Sc1YSZ) are synthesized by tape casting. The required porosity is attained by optimization of the content of pore-forming agent (starch) in the initial suspension and also by thermal treatment, on retention of the high strength characteristics of the substrate. The mechanical strength of supports is assessed by three-point bending method. The bilayered gas-tight electrolyte with the layers of ZrO2 stabilized by Y2O3 (8 mol %) (8YSZ) and Ce0.9Gd0.1O1.95 is obtained by magnetron sputtering followed by annealing at 1200°С. Studying the electrochemical characteristics of a SOFC with the La0.6Sr0.4CoO3 − δ cathode has shown that as the working temperature decreases, the contribution of electrode processes into cell's internal resistance increases which induces the specific power decrease down to 1.8, 1.4, and 0.9 W/cm2 at 850, 800, and 750°С, respectively. [ABSTRACT FROM AUTHOR]

Composite microcapsules based on polyelectrolytes and nanoparticles of iron oxides are synthesized, and the release of encapsulated high-molecular dextran under the influence of a low-frequency alternating magnetic field due to the magnetomechanical actuation of nanoparticles in a polymer shell is investigated. As a result of the chemical condensation of ferrous and ferric iron, single-domain magnetic spherical Fe3O4 nanoparticles are synthesized and characterized by transmission electron microscopy, dynamic light scattering, powder X-ray diffraction, and Mössbauer spectroscopy. Polyelectrolyte microcapsules from polyallylamine hydrochloride and sodium polystyrene sulfonate are modified with magnetic nanoparticles due to electrostatic adsorption on an oppositely charged polyelectrolyte layer. Dextran, labeled with tetramethyl rhodamine-5-isothiocyanate (TRITC-dextran), is used as the model substance for encapsulation; it is incorporated into CaCO3 particles (soluble cores for the formation of capsules) by coprecipitation. The capsule samples are examined by scanning electron microscopy, dynamic light scattering, and fluorescence confocal microscopy. The capsules are exposed to an alternating magnetic field with an amplitude of 100 mT and frequencies of 30–110 Hz. The content of labeled dextran in the shell of the microcapsules and the supernatant is determined using fluorimetry and fluorescence confocal microscopy. The duration of exposure and the frequency of the magnetic field, at which the maximum release of dextran from composite capsules is achieved, are established. Exposure to a low-frequency alternating magnetic field can lead to significant deformation of the shell of polyelectrolyte microcapsules modified with magnetic nanoparticles and successful release of the encapsulated substance. [ABSTRACT FROM AUTHOR]

Cobalt-containing dispersions were formed based on tin, bismuth, gallium, and a bismuth/tin alloy. The effect of the nature of the dispersion medium on the formation of the cobalt-containing dispersed phase has been established. The effect of the method of introducing the cobalt-containing component on the stability of the dispersion is shown. The effect of the concentration of the precursor solution on the size of cobalt oxide particles formed during the formation of a dispersed system has been studied. The fundamental possibility of the formation of catalytic systems based on gallium with a particle size of 450–540 nm is shown. [ABSTRACT FROM AUTHOR]

A two-step procedure to synthesize (3-fluoroadamantan-1-yl)methyl isocyanate from (3-hydroxyadamantane)acetic acid that involves fluorination with Ishikawa's reagent on the first step of the synthesis was developed. The reaction of (3-fluoroadamantan-1-yl)methyl isocyanate with aliphatic diamines gave 1,3-disubstituted bis-diureas in 60–97% yields. A strong decrease in the melting points of the obtained ureas (up to ∼70–144 °C) was observed upon introduction of the fluorine atoms at the bridgehead positions of the adamantane unit. [ABSTRACT FROM AUTHOR]

The molecular polarizability and dipole moments of the fragments of copolymer fluoroelastomers was evaluated by the quantum chemical method. It was shown that the polarity of fluororubbers is provided by the presence of vinylidene fluoride units. The dynamic mechanical analysis method was used to obtain the frequency and temperature dependencies of the storage modulus E′ and the mechanical loss tangent tan δ of fluororubbers and vulcanizates on their basis. The characteristic features of the influence of the rubbers composition and vulcanization on the mechanical and thermophysical characteristics of elastomers were established. The values of tensile strength and elongation at break were obtained for vulcanizates of the studied fluoroelastomers, as well as the Mooney viscosity and the compression set values. The crucial influence of the rubber polarity and the vulcanization network parameters on the specified parameters was identified. The swelling kinetics of rubbers and vulcanizates on their basis in 1,2-dichloroethane at 50°С was studied. The sorption limitation degree of the solvent at the appearance of the vulcanization network and its parameters were evaluated. It was found that with regard to the reduction in their equilibrium degree and swelling rate in dichloroethane, elastomers go in the following order: SKF-26 > Elaftor 3061R > Elaftor 7075 > Elaftor 1000R, symbatically to the decrease in their polarity. [ABSTRACT FROM AUTHOR]

A model of the input channel is developed for a two-rotor Roots vacuum pump. In numerical calculations of the input-channel gas flow by means of Ansys Fluent software, for different input pressures, pressure differences, and rotor angles, the flow rate coefficients obtained for the gas are in good agreement with the experimental values. [ABSTRACT FROM AUTHOR]

A one-step procedure has been developed for the synthesis of (3-bromoadamantan-1-yl)methyl isocyanate from 2-(3-bromoadamantan-1-yl)acetic acid and diphenylphosphoryl azide in 85% yield. The reac-tions of (3-bromoadamantan-1-yl)methyl isocyanate with aliphatic diamines and 4-(trans-4-aminocyclohexyl-oxy)benzoic acid gave a series of N,N′-disubstituted ureas and diureas in 52–85% yield. The hydrolysis of (3-bromoadamantan-1-yl)methyl isocyanate in the presence of a catalytic amount of DBU afforded symmetrical N,N′-bis[(3-bromoadamantan-1-yl)methyl]urea in 52% yield. [ABSTRACT FROM AUTHOR]

N,N′-Disubstituted ureas and thioureas containing a lipophilic optically active bicyclic fragment of natural origin were synthesized by reaction of (R)- and (S)-1,3,3-trimethylbicyclo[2.2.1]heptan-2-amine (prepared from the natural terpenoid fenchone) with aromatic isocyanates and isothiocyanates in up to 88 and 87% yield, respectively, with the goal of assessing the enantiomeric specificity of human soluble epoxide hydrolase (hsEH). The synthesized compounds were found to be promising as inhibitors of RNA virus replication and hsEH. [ABSTRACT FROM AUTHOR]

We study one-dimensional porous silicon photonic crystals by photoreflectance (PR) spectroscopy. We calculate the reflectance and PR spectra by transfer matrix method and obtain good agreement with experimental data. We investigate the dependence of the intensity of the PR spectra on the modulating radiation power and measure the nonlinear refraction coefficient of porous silicon. We show that the nonlinearity is due to thermal effect. [ABSTRACT FROM AUTHOR]

The synthesis of hollow nanostructured microspheres of strontium ferrite by microspheres is reported. The phase composition, morphology, and particle-size distribution of the obtained microspheres and the effect of the synthesis parameters on the morphology and particle-size distribution are investigated. It is established that synthesis by the spray-pyrolysis method formed hollow nanostructured microspheres with dimensions in the range 0.5 – 10.0 μm. The wall thickness was ~100 nm. The microspheres consisted of particles 10 – 20 nm in size. [ABSTRACT FROM AUTHOR]

A study is performed of the directional sensitivity of a two-coordinate neutron detector based on a 3 μm 10B layer and a wire chamber. The suppression of scattered neutron detection by the detector is observed, relative to data from the 3He counter. This is explained by strong absorption of neutron flux in the 10B layer when it is incident at a large angle to the plane of the detector, and by the energy of the 4He or 7Li secondary nucleus being insufficient to exceed the threshold energy if the nucleus is produced immediately after entering the 10B layer. [ABSTRACT FROM AUTHOR]

The feasibility of monitoring maximum energy of neutrons in the neutron flux from a source by analyzing pulse-height spectra from a 10B detector is investigated. Ionization losses of 4He and 7Li nuclei in two detector gaps are modeled. The clear experimental dependence of the position of the maximum and the shape of these spectra on and calculations in agreement with this dependence can be used to monitor the maximum energy of neutrons. [ABSTRACT FROM AUTHOR]