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Abstract: The chemical stability of Nd0.33Zr2(PO4)3fine-grained ceramics, which can be used for immobilization of rare earth elements (REE) that are part of high-level waste was studied. Single-phase Nd0.33Zr2(PO4)3submicron powders with the structure of the mineral kosnarite were prepared by colloid-chemical synthesis. Powders were prepared by successive annealing at 600, 800, and 900°C for 6 h at each stage. Nd0.33Zr2(PO4)3ceramic was Nd0.33Zr2(PO4)3ceramics was produced using spark plasma sintering method (SPS). The relative density of the ceramic was 89.9%; the average grain size was 5–20 μm. The chemical stability of the ceramic in the static mode at 90°C in distilled water and mineral water, as well as in acidic media (0.1 M HCl) and alkaline media (0.01 M NaOH), was studied. The ceramics have high hydrolytic stability. The influence of the contact medium on the rate and mechanism of Nd leaching from the surface of Nd0.33Zr2(PO4)3fine-grained ceramic samples was studied. The de Groot-van der Sloot model was used to analyze the resulting leaching rate Riagainst time tof experiment. Nd leaching occurs by dissociation of Nd from the ceramic surface in acidic medium, diffusion from the inner layers in alkaline medium and mineral water, and dissolution of the ceramic surface layer in distilled water.

With the advance of on-chip nanophotonics, there is a high demand for high-refractive-index and low-loss materials. Currently, this technology is dominated by silicon, but van der Waals (vdW) materials with a high refractive index can offer a very advanced alternative. Still, up to now, it was not clear if the optical anisotropy perpendicular to the layers might be a hindering factor for the development of vdW nanophotonics. Here, we studied WS2-based waveguides in terms of their optical properties and, particularly, in terms of possible crosstalk distance. Surprisingly, we discovered that the low refractive index in the direction perpendicular to the atomic layers improves the characteristics of such devices, mainly due to expanding the range of parameters at which single-mode propagation can be achieved. Thus, using anisotropic materials offers new opportunities and novel control knobs when designing nanophotonic devices.

A global trend towards miniaturization and multiwavelength performance of nanophotonic devices drives research on novel phenomena, such as bound states in the continuum and Mietronics, as well as surveys for high-refractive index and strongly anisotropic materials and metasurfaces. Hexagonal boron nitride (hBN) is one of the promising materials for future nanophotonics owing to its inherent anisotropy and prospects of high-quality monocrystal growth with an atomically flat surface. Here, we present highly accurate optical constants of hBN in the broad wavelength range of 250–1700 nm combining imaging ellipsometry measurements, scanning near-field optical microscopy and first-principles quantum mechanical computations. hBN's high refractive index, up to 2.75 in the ultraviolet (UV) and visible range, broadband birefringence of ∼0.7, and negligible optical losses make it an outstanding material for UV and visible range photonics. Based on our measurement results, we propose and design novel optical elements: handedness-preserving mirrors and subwavelength waveguides with dimensions of 40 nm operating in the visible and UV ranges, respectively. Remarkably, our results offer a unique opportunity to bridge the size gap between photonics and electronics.

Polyelectrolyte microcapsules and other targeted drug delivery systems could substantially reduce the side effects of drug and overall toxicity. At the same time, the cardiovascular system is a unique transport avenue that can deliver drug carriers to any tissue and organ. However, one of the most important potential problems of drug carrier systemic administration in clinical practice is that the carriers might cause circulatory disorders, the development of pulmonary embolism, ischemia, and tissue necrosis due to the blockage of small capillaries. Thus, the presented work aims to find out the processes occurring in the bloodstream after the systemic injection of polyelectrolyte capsules that are 5 μm in size. It was shown that 1 min after injection, the number of circulating capsules decreases several times, and after 15 min less than 1% of the injected dose is registered in the blood. By this time, most capsules accumulate in the lungs, liver, and kidneys. However, magnetic field action could slightly increase the accumulation of capsules in the region-of-interest. For the first time, we have investigated the real-time blood flow changes in vital organs in vivo after intravenous injection of microcapsules using a laser speckle contrast imaging system. We have demonstrated that the organism can adapt to the emergence of drug carriers in the blood and their accumulation in the vessels of vital organs. Additionally, we have evaluated the safety of the intravenous administration of various doses of microcapsules.

Mid-infrared (mid-IR) optical spectroscopy of molecules is of large interest in physics, chemistry, and biology. However, probing nanometric volumes of molecules is challenging because of the strong mismatch of their mid-infrared absorption and scattering cross-sections with the free-space wavelength. We suggest overcoming this difficulty by nanofocusing acoustic graphene plasmon polaritons (AGPs) – oscillations of Dirac charge carriers coupled to electromagnetic fields with extremely small wavelengths – using a taper formed by a graphene sheet above a metallic surface. We demonstrate that due to the appreciable field enhancement and mode volume reduction, the nanofocused AGPs can efficiently sense molecular fingerprints in nanometric volumes. We illustrate a possible realistic sensing sсenario based on AGP interferometry performed with a near-field microscope. Our results can open new avenues for designing tiny sensors based on graphene and other 2D polaritonic materials.

Vibration perturbations occurring during the operation of a laser interferometer with passive and active vibration isolation are investigated using a microvibration sensor based on micromechanical accelerometers. A description of the workstation is provided, and the optical layout of the device and the method of measurement are described. Analysis of the measurement results showed that, under the influence of random microvibration, the amplitudes of the surface vibrations and the vibrations of the microscope head are different, and the difference reaches values comparable to the resolution of the laser interferometer. It is shown that, in order to reduce the measurement errors of a laser interferometer, it is useful to perform active vibration isolation during the measurement.

The currently known methods for the preparation of vinyl ethers, vinyl sulfides and enamines are analyzed and described systematically. The published data on the reactions of alcohols, thiols and various nitrogen-containing compounds with acetylene, resulting in the corresponding vinyl derivatives, are considered. The attention is focused on the application of convenient acetylene sources. Other modern approaches to the synthesis of vinyl derivatives are described in detail, including vinyl exchange and metathesis reactions, various types of cross-coupling and cleavage of organic compounds. Some specific synthetic routes to vinyl ethers, vinyl sulfides and enamines are presented in the last Section.The bibliography includes 262 references.

Background: One of the labor-consuming and dangerous operations in technological process of processing reactors is the one on transportation of firm wastes, as it is necessary to take into account the danger of materials to an environment and their harmful influence on health of the attendants and population. Objective: The recent paper is devoted to theoretical and experimental study of two phase (particle/air) media propagation inside a pipeline (part of pulsed pneumatic transport devices where materials are delivered to containers) with attention on possible harm influence of the flow on the tube walls, especially at the pipelines bends. Methods: Physical model corresponds to experimental study described in the patents. Numerical modeling was performed within the framework of model of non-stationary two-dimensional motion of ideal compressible media on the basis of laws of conservation of mass, momentum and energy. The thermodynamic flow field has been computed both in gas and solid phases. Results: Processes of particles mutual interactions, coalescence, fragmentation, interaction with a tube surface and motion have been investigated in detail. Interface borders have been considered as contact discontinuity surfaces. Modeling was performed numerically on the basis of the method of individual particles. The comparison of the computational and experimental data stated in patents was executed as well. Conclusion: It was found that the greater the radius of the pipeline bend R, the smaller value of gas pressure we have in the bend, but this effect becomes insignificant for R > 2.2m. The values of gas velocity at the bend have little variations depending on R. For small values of R (close to right angle of the bend) inverse motion of the particles is possible that may result in blocking of the flow. The formation of jet (consisting of particles) may take place at changing of radius R value (up to R = 1m). This may lead to sufficient damage to pipeline walls. At R > 4m volumetric concentration of particles starts to grow at the outer wall of the bend and effect of fragments dragging takes place that is also harmful for device operation. So if the value of radius R belongs to the interval (1.5; 3.5)m, we have minimal damage for the system operation.

Although mutations in the GJB2gene sequence make up the majority of variants causing autosomal-recessive non-syndromic hearing loss, few large deletions have been shown to contribute to DFNB1 deafness. Currently, genetic testing for DFNB1 hearing loss includes GJB2sequencing and DFNB1 deletion analysis for two common large deletions, del(GJB6-D13S1830) and del(GJB6-D13S1854). Here, we report frequency in Russia, clinical significance and evolutionary origins of a 101 kb deletion, del(GJB2-D13S175), recently identified by us. In multiethnic cohort of 1104 unrelated hearing loss patients with biallelic mutations at the DFNB1 locus, the del(GJB2-D13S175) allele frequency of up to 0.5% (11/2208) was determined and this allele was shown to be predominantly associated with profound sensorineural hearing loss. Additionally, eight previously unpublished GJB2mutations were described in this study. All patients carrying del(GJB2-D13S175) were of the Ingush ancestry. Among normal hearing individuals, del(GJB2-D13S175) was observed in Russian Republic of Ingushetia with a carrier rate of ~1% (2/241). Analysis of haplotypes associated with the deletion revealed a common founder in the Ingushes, with age of the deletion being ~3000 years old. Since del(GJB2-D13S175) was missed by standard methods of GJB2analysis, del(GJB2-D13S175) detection has been added to our routine testing strategy for DFNB1 hearing loss.

Remote navigation and targeted delivery of biologically active compounds is one of the current challenges in the development of drug delivery systems. Modern methods of micro- and nanofabrication give us new opportunities to produce particles and capsules bearing cargo to deploy and possess magnetic properties to be externally navigated. In this work we explore multilayer composite magnetic microcapsules as targeted delivery systems in vitro and in vivo studies under natural conditions of living organism. Herein, we demonstrate magnetic addressing of fluorescent composite microcapsules with embedded magnetite nanoparticles in blood flow environment. First, the visualization and capture of the capsules at the defined blood flow by the magnetic field are shown in vitro in an artificial glass capillary employing a wide-field fluorescence microscope. Afterward, the capsules are visualized and successfully trapped in vivo into externally exposed rat mesentery microvessels. Histological analysis shows that capsules infiltrate small mesenteric vessels whereas large vessels preserve the blood microcirculation. The effect of the magnetic field on capsule preferential localization in bifurcation areas of vasculature, including capsule retention at the site once external magnet is switched off is discussed. The research outcome demonstrates that microcapsules can be effectively addressed in a blood flow, which makes them a promising delivery system with remote navigation by the magnetic field.

The aim of the presented work is to establish relationship of behavior of stress relaxation process in 5056 alloy in vacuum conditions for stress levels of 116 MPa, 83 MPa and 50 MPa and temperatures of 293 K and 353 K. Method of circular specimens with equal flexural strength was used as the main method for stress relaxation testing. Results of the studies allowed to develop the advanced methodology for evaluation of stress relaxation, which increases measurement accuracy up to 0.04 MPa. Increase of accuracy was achieved using the proposed new shape of a specimen of equal flexural strength, its manufacturing technology and developed design of accessories for precision marking. It was established that for studied temperatures stress relaxation in vacuum is occurring more intensively independently from level of initial stress. That fact can be explained by increase of influence of dislocation mechanism on stress relaxation. The results of the presented studies serve as a basis for increase of reliability and consistency of dimensions of elements of aircraft's structure and their parts and components, which are operating in vacuum conditions.

Nanocomposite coatings are promising for a range of practical applications, and layer-by-layer assembly (LbL) is a versatile tool for nanocomposite formation. However, conventional LbL is a quite laborious procedure taking a lot of time to reach a sufficient thickness of the coatings required for practical applications. Herein, we proposed a novel variant of the LbL approach based on the deposition of hydrophilic polyelectrolyte molecules from a polar solvent and hydrophobic magnetite nanoparticles (NPs) from a nonpolar dispersion medium with an intermediate washing in the same polar solvent. The composite multilayers formed in this way exhibit exponential growth of the thickness and mass. On the basis of quartz crystal microbalance (QCM), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM), and surface profile measurements, we propose a model describing the driving force of multilayer formation and the factors leading to nonlinear growth of their mass and thickness. The results allow one to expand the understanding of the mechanism of the LbL assembly in order to form multifunctional nanocomposites in a more efficient way.

Computer simulation of the process drawing a cup from the 5056 alloy sheet material was conducted. An influence of a real structure of a grain-oriented material on a stress-strain state was shown. The profiles of the formed festoons, their gage interference along the generator line and perimeter were measured. Values of a maximum drawing force for the isotropic, anisotropic, and grain-oriented by 40 and 70% of finite element sample models were defined.

An equilibrium mixture of monoclinic pyrrhotite and pyrite was synthesized in the eutectic AlCl3- KCl melt at 525 K. The reaction 7FeS2(cr) + 12Ag(cr) = 8Fe0.875S(cr) + 6Ag2S(cr) was studied by an electromotive force technique in an all-solid-state electrochemical cell with an Ag+-conductive solid electrolyte in Ar at atmospheric pressure: (-) Pt | Ag | AgI | Ag2S, Fe0.875S, FeS2| Pt (+). In the 490-565 K temperature range a linear electromotive force vs. temperature trend was obtained from which the temperature dependence of the sulfur fugacity was determined for the monoclinic pyrrhotitepyrite equilibrium: logfS2(mpo+py) = 14.079 - 14406⋅T-1, (500 < T/K < 565). In addition, standard thermodynamic functions were calculated for monoclinic pyrrhotite Fe0.875S at 298 K and atmospheric pressure: ΔGf(mpo, 298.15 K) = -(136 200 ± 3000) J/mol, S°(mpo, 298.15 K) = (66.7 ± 1.3) J/(mol-K), ΔHf(mpo, 298.15 K) = -(157 400 ± 3000) J/mol. Gaseous sulfur, S2-ideal gas at 1 bar (105Pa) pressure- was taken as a standard state for sulfur.

In this paper an image inpainting approach based on the construction of a composite curve for the restoration of the edges of objects in an image using the concepts of parametric and geometric continuity is presented. It is shown that this approach allows to restore the curved edges in damaged image by interpolating the boundaries of objects by cubic splines. A tensor analysis is used for classification of texture and non texture regions. After edge restoration stage, a texture restoration based on exemplar based method is carried out. It finds the best matching patch from another source region and copies it into the damaged region. For non texture regions a Telea method is applied.

This paper describes a novel image reconstruction method based on modified exemplar based technique. This modification allows to choose sub-optimally image-adaptive form and size of the block in order to find similar patches, number of which is further increased by rotation of these blocks. We show that the efficiency of image reconstruction depends on the choice of block size for the exemplar based method. Proposed block size selection adaptivity allows to obtain a smaller reconstruction error than that of the traditional method as well as other state-of-the-art image inpainting methods. We demonstrate the performance of a new approach via several examples, showing the effectiveness of the proposed algorithm in removal of small and large objects on the test images.

A source capable of producing dense plasma clusters moving with high velocity is investigated. Parameters of the source could be acceptable for many fusion or confinement plasma experiments as a fuel or plasma source. The source generates a cluster of plasma density exceeding 10²² m^-3 with a total number of released particles in the range 10¹⁷-10²¹, the efficiency of ionization reaches 90% and the flow velocity of the plasma is &geq;10 km s^-1.

1.The influence of the nature of the support on the catalytic activity of technetium has been established for reactions of cyclohexane and isopropanol dehydrogenation. The most active are Tc/MgO and Tc/REE oxides; the least active are Tc/SiO2, Tc/C, and Tc/TiO2.2.Temperature-programmed reduction of the system consisting of ammonium pertechnetate and a support has shown that SiO2 plays the role of a dispersing agent, whereas Y2O3 and ?-Al2O3 interact with the NH4TcO4.3.When CO is adsorbed on Tc ?-Al2O3 or Tc/Y2O3, linear and bridge surface structures are formed. On Tc/MgO, in addition to these structures, multicenter carbonyl structures are found.4.An examination of diffuse reflection spectra in all stages of catalyst preparation has shown that in the most active catalysts, an ionic species of technetium is preserved along with metallic technetium; this ionic species has a modifying effect on the processes of alcohol and cyclohexane dehydrogenation.

Manganites with a spinel structure MMn2O4 (M = Co, Cu, Zn, Mo) and M10.5M20.5 Mn2O4 (M = Co, Cu, Zn, Mg) have been synthesized and tested in the catalytic oxidation of CO, C3H6, and ethylbenzene. The dependence of the catalytic activity of the manganites on the nature of the cation has been established. The spinels containing transition metal ions (Cu, Co) are more active. A relation between catalytic and adsorption properties of manganites has been established. The participation of the lattice oxygen in the oxidation of CO to CO2 has been found. The mechanism of the oxidation is discussed.

A method has been developed for producing nickel-molybdenum alloys with 28–50% Mo by a powder metallurgy process comprising hydrostatic pressing of mechanical Ni + Mo mixtures, sintering of resultant blanks, and their subsequent hot plastic working (forging or rolling) into rods and sheets. A study was made of the workability of nickel-molybdenum alloy blanks in forging and hot rolling. It was found that such alloys with 28–40% Mo are characterized by satisfactory, and NM45 alloy by poorer, workability, while NM50 alloy is not amenable to plastic working. Thus, the nonworkable (when produced by the conventional metallurgical process) 36–40% Mo alloys acquire satisfactory workability through the use of the powder metallurgy technique, which enables them to be employed in industry instead of molybdenum for operation in highly corrosive environments.

1.It is shown that in the whole pressure range investigated (9–180 kg/mm2) coarse-grained spherical tungsten powders surpass standard fine-grained powders in compressibility.2.In a wide pressure range (from 9 to 100–150 kg/mm2) the compressibility of the powders investigated is satisfactorily described by M. Yu. Bal'shin's second equation. The limiting pressure below which this equation is applicable falls with increase in the relative density of powders.3.For spherical powders the character of density, microstress, and electrical resistivity vs compaction pressure curves changes at pressures above 100 kg/mm2, which is apparently indicative of a change in the mechanism of their densification.

1.A study was made of the vacuum sintering of pure TiC and TiC with an activating addition (1% Ni).2.The addition of 1% of nickel to TiC activates the sintering process. The relative density and linear shrinkage of nickel-containing titanium carbide sintered at 1300°C are the same as those of pure titanium carbide sintered at 2200°C.3.During the vacuum sintering of TiC with a nickel addition, the nickel evaporates over the temperature range 1500–1800°C. Specimens sintered in a vacuum at 2000°C contain virtually no nickel.4.High-temperature heat treatment has no significant effect upon the lattice parameters of TiC and TiC + 1% Ni, which shows that no decarbidization of TiC occurs in the course of vacuum sintering at high temperatures.

The modification of the BRST approach suggested by the authors and based on using the Lie superalgebra l(1, 1) as the full algebra of the BRST symmetry is applied to the problem of calculating BRST operator cohomologies. The calculation is done for the class of BRST-Fock theories. The operator cohomologies are proved to be trivial. The result is interpreted as the analog of the no-ghost theorem on the level of observables.