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Three-layer iron-rich Fe3+xSi1−x/Ge/Fe3+xSi1−x (0.2 < x < 0.64) heterostructures on a Si(111) surface with Ge thicknesses of 4 nm and 7 nm were grown by molecular beam epitaxy. Systematic studies of the structural and morphological properties of the synthesized samples have shown that an increase in the Ge thickness causes a prolonged atomic diffusion through the interfaces, which significantly increases the lattice misfits in the Ge/Fe3+xSi1−x heterosystem due to the incorporation of Ge atoms into the Fe3+xSi1−x bottom layer. The resultant lowering of the total free energy caused by the development of the surface roughness results in a transition from an epitaxial to a polycrystalline growth of the upper Fe3+xSi1−x. The average lattice distortion and residual stress of the upper Fe3+xSi1−x were determined by electron diffraction and theoretical calculations to be equivalent to 0.2 GPa for the upper epitaxial layer with a volume misfit of −0.63% compared with a undistorted counterpart. The volume misfit follows the resultant interatomic misfit of |0.42|% with the bottom Ge layer, independently determined by atomic force microscopy. The variation in structural order and morphology significantly changes the magnetic properties of the upper Fe3+xSi1−x layer and leads to a subtle effect on the transport properties of the Ge layer. Both hysteresis loops and FMR spectra differ for the structures with 4 nm and 7 nm Ge layers. The FMR spectra exhibit two distinct absorption lines corresponding to two layers of ferromagnetic Fe3+xSi1−x films. At the same time, a third FMR line appears in the sample with the thicker Ge. The angular dependences of the resonance field of the FMR spectra measured in the plane of the film have a pronounced easy-axis type anisotropy, as well as an anisotropy corresponding to the cubic crystal symmetry of Fe3+xSi1−x, which implies the epitaxial orientation relationship of Fe3+xSi1−x (111)[0−11] || Ge(111)[1−10] || Fe3+xSi1−x (111)[0−11] || Si(111)[1−10]. Calculated from ferromagnetic resonance (FMR) data saturation magnetization exceeds 1000 kA/m. The temperature dependence of the electrical resistivity of a Ge layer with thicknesses of 4 nm and 7 nm is of semiconducting type, which is, however, determined by different transport mechanisms.

Hydrotreatment of birch wood pyrolysis liquid (PL) was carried out at 350 °C and 6.0 MPa initial hydrogen pressure (RT) for 4 h in a batch autoclave using promising high-loading Ni-based catalysts stabilized by SiO2. Different additives (Cu, Mo, Cr, P) were used to modify the catalysts. The products in liquid organic (OPh) and aqueous phases (AqPh) after PL hydrotreatment were characterized by different methods, such as gas chromatography-mass spectrometry (GC–MS), Fourier-transform infrared (FTIR) spectroscopy, gel permeation chromatography (GPC), etc. Herein, the performance of the catalysts was evaluated by considering the yield and chemical composition of the products (gaseous phase, OPhs, AqPhs, and coke). For the MoCr-containing system, a higher yield of the aqueous phase with low O/C ratio was observed that could be explained by more effective hydrodeoxygenation of water-soluble compounds due to Ni-Mo-Cr solid solutions and coordinatively unsaturated Cry+ and Mox+ sites. P-modified NiCuMoP-SiO2 and NiCrP-SiO2 catalysts reveal more intense CO2 formation very likely due to decarboxylation over Ni3P particles, thus leading to the decrease in the oxygen content in organic phase to 14 wt.%. Fresh reduced catalysts were examined by CO chemisorption, X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM) to provide insights into the structure and morphology. High resistance to coke formation was evidenced according to CHNS analysis of spent samples, besides, the stability of catalysts was additionally assessed by X-ray diffraction.

В статті наведені дані останніх клінічних досліджень, в яких представлені переваги призначення таргетного препарату кабозантиніб, інгібітору тирозинкіназ MET, AXL, рецепторів VEGF, у лікуванні метастатичного світлоклітинного раку нирки як у другій, так і в першій лінії терапії.

A comparison is made between theoretical and experimental studies of the position of eutectics in two-component systems consisting of tetrachlorethylene and n-alkanes with 10 to 20 carbon atoms. Data on the composition of the eutectics, their temperatures of melting, and the coefficients of activity of each component are calculated in three ways: using experimental data, the UNIFAC procedure, and a modified UNIFAC Dortmund procedure. The equilibria of liquid–solid phases are studied theoretically using Schroder’s equation and the UNIFAC and modified UNIFAC Dortmund procedure. Experimental data were obtained via DTA. Relative deviations of the calculated melting temperatures and compositions of the eutectics from the corresponding experimental data are reported.

Ni-phosphides present a promising alternative to the conventional hydrotreatment NiMo sulfides. The hydrotreatment catalysts are supported on Al2O3 granules, and the similarly Al2O3 supported Ni-phosphide catalysts provide an interesting case for comparison. In this work the Ni-phosphide catalysts supported on Al2O3 granules were prepared using two procedures: 1) temperature-programmed reduction of “phosphite”-type precursor in hydrogen flow (TPR_I catalyst), 2) treatment of Ni nanoparticles with triphenylphosphine solution at elevated temperature (LP catalyst). The catalysts were characterized by ICP-AES chemical analysis, N2 physisorption, XRD, TEM, XPS, 27Al MAS NMR. The Ni2P particles were found in LP samples, while TPR method gives the mixture of Ni12P5 and Ni2P particles and amorphous AlPO4 on the alumina surface. The behavior of granulated Ni phosphide and conventional sulfided NiMo/Al2O3 catalysts was compared in hydroprocessing of straight-run gas oil (SRGO) at 340 °C, 4 MPa, V(H2)/V(feed) - 400 Nm3/m3, LHSV - 1,5 h−1. Hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) activity of nickel phosphide catalysts were shown to be lower in comparison with NiMo/Al2O3. Hydrotreating of S-containing model compounds (DBT, 4-MDBT, 4,6-DMDBT) was carried out over TPR_I catalyst, and a negative effect of dimethyl disulfide (DMDS) and acridin additions on the HDS activity was observed.

A procedure for the synthesis of 2-anilino-6-hydroxy-3-phenylpyrimidin-4(3H)-one (mafedine) without using alkali metal ethoxides has been developed and optimized. Mafedine-related compounds that can be formed as possible impurities have been prepared, and conditions for joint determination of these impurities by HPLC with spectrophotometric detection have been found. The structure of the mafedine decomposition product in solution has been identified by HPLC-ESI/MS.

Thermogravimetry (TG) was used to obtain experimental data on the pyrolysis of sorghum biomass in an inert atmosphere at a heating rate of 3 K/min. Mathematical modeling of the process was carried out based on a three-component kinetic model. According to the model, biomass was represented by the sum of three components (hemicellulose, cellulose, and lignin), the pyrolysis of which proceeds according to independent parallel first-order reactions. To determine the kinetic parameters of the model, a step-by-step procedure based on difference in the temperature ranges of hemicellulose, cellulose, and lignin pyrolysis was proposed for experimental data processing. The kinetic parameters of first lignin, then cellulose, and finally hemicellulose were determined by recognizing and processing the corresponding fragments of TG data. The activation energies of pyrolysis of the biomass components were 25 kJ/mol for lignin, 105 kJ/mol for cellulose, and 30 kJ/mol for hemicellulose. The discrepancy between the experimental and calculated TG data in a temperature range above 440 K was 0.6%.

Natural waters usually demonstrate the disturbance of radioactive equilibrium between parent 238U and and daughter 234U (usually, 234U/238U ≈ 0.8–3 in activities). The ratio of 234U/238U > 10 found in groundwaters can be explained by climatic variations, and it is result of 234U accumulation in permafrost rocks during cold periods and its more rapid loss compared to 238U during thawing. We tested this hypothesis for data on uranium isotope composition in water, and also chemo- and biogenic formations of the World Ocean. Most significant enrichment in 234U is discovered in the northern and internal seas during climatic warmings, which is consistent with an inferred influence of the permafrost formation and degradation on the anomalous increase of 234U/238U in groundwaters. Sampling of the Barents Sea shows that the uranium-234 enrichment in oceanic water increases with increase (a) of isolation from oceanic circulation system, (b) of the relative length of the coastal line, (c) and the contribution of continental waters to the chemical balance of the basin.

We report a flexible approach to the synthesis of phenanthrene-like heterocycles through organocatalytic ANRORC (Addition of the Nucleophile, Ring Opening, and Ring Closure) reaction of electron-deficient 3-vinylchromones with cyanoacetamide. Addition of highly basic DBU (1,8-diazabicyclo[5.4.0]undec-7-ene) or tetramethylguanidine (TMG) at 80 °C leads to chromeno[4,3-b]pyridines in good yields, whereas Et3 N at 20 °C made it possible to obtain the less accessible pyrano[3,2-c]chromenes and their 2-imines. The synthesis proceeds in mild conditions (EtOH, 20-80 °C), is versatile and applicable for a wide scope of reactants. The obtained compounds show bright fluorescence in the range 460-595 nm with high quantum yields (up to 0.84) in various solvents (MeCN, DMSO, EtOH, H2 O).

The paper presents the results of studies of the structure and properties of a fluorohydrite binder modified by a chrysotile nanotubes dispersion in a medium of calcium nitrate solution. It is shown that addition of this modifier into the anhydrite composition leads to a 106-fold decrease in electrical resistance. Microstructural analysis of the fluorohydrite composition showed changes in the morphology of new formations with the creation of crystalline hydrates of increased density. The presence of elongated nanocrystals on the surface of the hardened matrix was noted. In addition, IR spectrum absorption lines, prove the presence of calcium nitrate in the pore space of the composition, which contributes to a significant decrease in the electrical resistance of the developed composite.

In this paper, we review both practical and theoretical assessments for evaluating radon geohazards from permafrost landforms in northern environments (>60º N). Here, we show that polar amplification (i.e. climate change) leads to the development of thawing permafrost, ground subsidence, and thawed conduits (i.e. Taliks), which allow radon migration from the subsurface to near surface environment. Based on these survey results, we conjecture that abruptly thawing permafrost soils will allow radon migration to the near surface, and likely impacting human settlements located here. We analyze potential geohazards associated with elevated ground concentrations of natural radionuclides. From these results, we apply the main existing legislation governing the control of radon parameters in the design, construction and use of buildings, as well as existing technologies for assessing the radon hazard. We found that at present, these laws do not consider our findings, namely, that increasing supply of radon to the surface during thawing of permafrost will enhance radon exposure, thereby, changing prior assumptions from which the initial legislation was determined. Hence, the legislation will likely need to respond and reconsider risk assessments of public health in relation to radon exposure. We discuss the prospects for developing radon geohazard monitoring, methodical approaches, and share recommendations based on the current state of research in permafrost effected environments.

Electrical conductivity and gas sensitivity of $\alpha $ -Ga $_{2}\text{O}_{3}/\varepsilon $ ( $\kappa $ )-Ga2O3 structures were measured for oxygen concentrations ranging from 2 % to 100 % and temperatures ranging from 25 °C to 220 °C. It was found that the oxygen sensitivity of the structures depended on the donor dopant concentration. The $\alpha $ -Ga $_{2}O_{3}/\varepsilon $ ( $\kappa $ )-Ga2O3 structures doped with $\sim 1.5\times 10^{17}$ cm−3 of Sn showed high sensitivity to O2 in the temperature range from 180 °C to 220 °C and at the bias voltage below 7.5 V. This effect can be attributed to the chemisorption of oxygen molecules on the surface of structures, which reduces energy barriers between $\varepsilon $ (k)-Ga2O3 grains.

A procedure has been developed for the synthesis of 6,7-dihydroindazoles and 7,8-dihydroquinazolines by reaction of 3,4-dihydroxanthone derivatives with 1,2- and 1,3-binucleophiles (hydrazine, guanidine). The reaction occurred under mild conditions (methanol, 20-65°C) with high yields.

The suspension polymerization in octafluorobutane, initiated by Ziegler–Natta catalyst system, has been used to synthesize ultra-high molecular weight poly(1-hexene), poly(1-octene), and poly(1-decene) of regular structure with high yields. This technique makes it possible to successfully carry out reactions at close to room temperature, followed by easy isolation of polymer products. The regularity of the structure of the synthesized polymers was proved based on the data of 1H and 13C NMR spectroscopy. Using gel permeation chromatography, data on the molecular weight distribution of polymer molecules were obtained. They indicated that the weighted average mass of the synthesized polymers is many times higher than the mass of polyolefins produced by the classical technique of homogeneous polymerization.

The article presents up-to-date information about diagnostic methods for one of the most common and socially significant hepatological diseases-alcoholic liver disease. The most frequent clinical manifestations of this pathology are asthenic, dyspeptic, right hypochondrium, cholestatic, neurological, edematous-ascitic and hemorrhagic syndromes. Validated questionnaires are intended for standardized alcohol use screening, the «gold standard» among which is the «AUDIT» questionnaire aimed at identifying alcohol use disorders. Most of the physical signs of chronic alcohol abuse are presented in the modified LeGo grid. Direct indicators (markers) of laboratory diagnosis of alcohol use include the determination of phosphatidyl ethanol and ethyl glucuronide in blood serum and urine; ethyl glucuronide and fatty acid ethyl esters in hair; ethanol, aminotransferase, peroxidase, ethylglucuronide, ethyl sulfate, haptoglobin, etc., in saliva. Indirect markers include macrocytic anemia, neutrophilic leukocytosis, increased activity of gamma-glutamyl transpeptidase, transaminases, de Ritis coefficient, bilirubin, alkaline phosphatase, serum immunoglobulin A and gamma globulins. Determination of carbohydrate-deficient transferrin is recommended as a preferred marker of alcohol intoxication. In order to determine the degree of fibrosis, predictive diagnostic serum tests are used, both non-proprietary («APRI», «Forns») and commercial («Fibrometer», «Hepascore», «Fibrospect» etc.). The methods of visual diagnostics of liver diseases include ultrasound, magnetic resonance and computed tomography, which can determine steatosis, exclude other causes of liver damage, reveal signs of severe fibrosis or cirrhosis, as well as their complications, but none of them allows to establish the etiology of the lesion. A promising direction is to determine the degree of steatosis when measuring the controlled parameter of ultrasound attenuation, implemented in the «Fibroscan» apparatus. The most accurate methods for diagnosing steatosis today are magnetic resonance imaging of the liver in the mode of determining the proportion of fat, weighted by proton density, and proton magnetic resonance spectroscopy. To determine the degree of fibrosis, a transient, two-dimensional shear wave and magnetic resonance elastography are used. Biopsy followed by morphological examination is the «gold standard» for the diagnosis of alcoholic liver disease, which confirms the presence of liver damage, establishes its stage and often allows confirming alcoholic genesis. However, this procedure has a number of significant drawbacks, so it is advisable to use non-invasive diagnostic techniques for screening, primary examination and further monitoring of the patient’s condition in dynamics.

Results are presented from calculating the spectra of weakly-bound triatomic molecular systems: the Helium trimer and helium–helium alkali molecules. Calculations are made on the basis of the Faddeev equations in the total orbital momentum representation. The existence of excited states with nonzero total orbital momentum of some molecules is confirmed.

The mechanism of synthesis of yttrium-aluminum garnet Y3Al5O12 (YAG) from a mixture of yttrium and ammonium carbonates NH4Y(CO3)2∙H2O with aluminum and ammonium hydroxycarbonates NH4AlCO3(OH)2 is shown to be different from the mechanism of synthesis from a mixture of hydrated yttrium and aluminum oxides. Calcination of a mixture of hydrated oxides leads to the formation of both Y3Al5O12 (YAG) and the impurity phases Y4Al2O9 and YAlO3, whereas monophase YAG is formed after a mixture of carbonates undergoes calcination. The difference in the mechanism of YAG synthesis is probably due to the difference in particle sizes formed after carbonates and hydrated oxides undergo calcination.

Porous plastics are used in various fields of industry, including radio- and electrotechnical fields. They are characterized by good heat- and sound isolating, dielectric and mechanical properties as well as by resistance to effect of various external factors during operation. The problem of estimation of effective permittivity of foam-polymer materials with a large volume fraction of pores, in particular, polyepoxide foam materials, has been considered. Two methods for solving it, both based on the matrix have been proposed. In the first method the matrix is considered as a polyepoxide binder, and the cavities filled with gas are taken as inclusions. In the second method the polyepoxide walls, separating cavities, are taken as inclusions, and gas filling cavities is considered as a matrix. To obtain the formulas for calculation, both methods use a generalized singular approximation of the theory of random fields. Based on the obtained expressions, the model calculations of the effective permittivity of a macroscopically isotropic foam material with a polymer binder based on E-20 and the cavities filled with freon, depending on the apparent density of the material, have been made. The calculations in the generalized singular approximations have been carried out for two of its variants: when the matrix was considered as a comparison medium; and, also by the self-consistent method. In the calculations using the second method two variants of the shape of the cells of the material have been considered: a weakly leaked or heavily leaked polyhedron. The calculated dependences obtained by all me-thods have shown the qualitative compliance with the experimental data.

The factors determining the mechanical properties of plastic polymeric foams are systematized. A unification procedure for their deformation behavior in the range of strains not higher than the forced elasticity limit of the material is proposed. The universal character of the deformation process is described by a unified strain curve and ratios of the main mechanical characteristics of the material, which are independent of the chemical nature of the polymer, the structural parameters of the foam, and the temperature–rate deformation conditions. The deformation behavior of monolithic and foam plastics and inorganic plastic bodies is shown to be similar.

An algorithm of software complex is developed to process data of lidar gas analysis in IR wavelength range for a horizontal path of atmospheric sensing. The complex comprises: the module of writing data from atmospheric lidar sensing, module of absorption cross-section calculation, and module of methane concentration profile retrieval. The software complex for processing lidar gas analysis data, developed on the basis of the created algorithm, makes it possible to obtain retrieved methane concentration profiles along 1 km sensing path from the set of recorded return signals. The modules for writing data from atmospheric lidar sensing and for retrieving methane concentration profiles allow for a visual control of recorded return signals and retrieved methane concentration profiles. We present an example of retrieving methane concentration profile from lidar data that is obtained in Tomsk.

Migraine and its comorbid conditions are pathogenetically associated with many factors, including hemorheological disorders. A class of drugs with a 5-HT2A antagonistic mechanism of action, is promising for the prevention and treatment of migraine attacks and concomitant pathologies.The aim of the research is to study and compare a hemorheological activity of anti-migraine drugs, antagonists of 5-HT2A receptors of cyproheptadine, and a new drug that completed preclinical studies of the 1-(2-diethylaminoethyl)-2-(4-methoxyphenyl)-imidazo[1,2-a]benzimidazole derivative of the RU- 31 compound.Materials and methods. The study of the hemorheological activity of the RU-31 compound and cyproheptadine, was carried out using an experimental model of rabbit blood hyperthermia in vitro. Pentoxifylline was used as a reference drug. In the course of the work, the parameters of blood viscosity, aggregation and deformability of erythrocytes were recorded.Results. It has been established that in the concentration of 1 μM, the RU-31 compounds reduce blood viscosity by 17% at high shear rates, which is comparable with pentoxifylline in the concentration of 100 μM on the activity level. In the concentration of 1 μM, cyproheptadine also causes a general tendency to reduce blood viscosity at high shear rates, being inferior in activity to the RU-31 compound and pentoxifylline. In the concentration of 1 μM, the RU-31 compound has a pronounced effect on the aggregation ability of erythrocytes in autologous plasma, reducing the aggregation rate by 70%, while the level of activity is not inferior to the drug compared to pentoxifylline in the concentration of 100 μM, and surpasses the drug cyproheptadine. For the RU-31 compound and cyproheptadine, no significant effect on the deformability of erythrocytes has been shown.Conclusion. The capacity of cyproheptadine and the RU-31 compound to influence the rheological properties of blood by reducing blood viscosity and aggregation of erythrocytes has been revealed.

An empirical formula is derived for the temperature of polyurethane shock absorbers of different hardness in cyclic loading as a function of the compressive strain, loading frequency, and vibrational amplitude.

Multilayer graphene oxide was synthesized by anodic oxidation of dispersed graphite, and the efficiency of its use as an electrode material for a supercapacitor was shown. In an alcohol suspension, the thickness of multilayer graphene oxide particles is less than 0.1 μm with an area of more than 100 μm2. The multilayer graphene oxide electrode has a high specific capacity of 107 F g–1 and a high charge retention rate of 97% after 5000 cycles at a current of 2 A g–1. The multilayer graphene oxide electrode demonstrated a maximum specific energy of 8.7 W h kg–1 at a current density of 0.1 A g–1 and a maximum power of 2291.1 W kg–1 at a current density of 4 A g–1. The impedance data at various DC voltages showed that after 5000 cycles, the charge transfer resistance increases by 26%. It was found that multilayer graphene oxide synthesized by the electrochemical method is a promising electrode material for producing a symmetric supercapacitor.

The methods of transmission and scanning electron microscopy are used to study the evolution of the structure of a welded joint of steels 32G2 and 40KhN in the thermomechanically affected zone (TAZ) under rotary friction welding (RFW). EBSD analysis is used to certify the microstructure in different parts of the TAZ and to calculate the densities of the low- and high-angle boundaries. It is shown that complex processes of dynamic recrystallization combining several mechanisms develop in all these regions of the TAZ. Typical differences in the structures of the mobile (steel 40KhN) and immobile (steel 32G2) parts of the billets are described.

We have discovered a silica-supported metallocene catalyst that produces large, open, porous polyolefin granules that can be easily and quantitatively deconstructed into their constituent polyolefin grains (Gₚ) by lightly crushing any granule. Three such polymerization products have been examined as follows: two heterophasic, comprising isotactic polypropylene (iPP) and polyethylene (PE), and one monophasic, comprising iPP. Deconstruction of granules from each product was followed by quantitative examination by optical microscopy of hundreds of grains. These data have enabled the first statistically robust demonstrations of lognormal distributions of polymer grain size and sphericity. While the lognormal results are not surprising per se, they offer the first quantitative demonstration of such distributions, rather than the unimodal distribution used in physical models since the introduction of the multigrain model over 30 years ago. Three contributions to the lognormal size distribution of the polymer grains are identified: dominant among these is the distribution of simple spheroidal polymer grains. For these simplest of grains, we also give the special notation “primaries”. The two remaining more complex grain topologies are constructed from primaries. One of these topologies is created from two or more fused, or attached, polymer primaries. The third type of grain topology is constructed from three or more fused primaries where the primary aggregate contains at least one void within the grain. In all, the polymer grains range in average diameter from 40 to as large as 470 μm. The median Gₚ diameter measured for all grains in each of the three products ranges from 83 to 150 μm. Between 6 and 16% of polymer grains have optically detectable voids, and grains with voids have on average 40–100% larger diameters than both the aforementioned solid grains denoted primaries and fused primaries. A simple morphological model is proposed for the dispersion of size and shape observed. Based on the data and model, the smallest supported catalyst grain, from which the polymer primary is grown, is calculated independently for each polymer product. These are ∼4–7 nm in diameter, or within the range of basic SiO₂ building blocks reported or calculated for spray-dried silica. Polarized light microscopy examination of isolated spheroidal primaries shows that chains in the heterophasic products have a preferential orientation, with chains aligning more or less along the radius of each primary, whereas chains in the iPP product show no preferential orientation. The morphology, or texture, of iPP and high-density polyethylene (HDPE) in a polymer primary taken from one of the heterophasic granule products was examined by scanning transmission electron microscopy. This examination, together with another for a closely related heterophasic product made with the same catalyst, shows that these two normally immiscible polyolefins are dispersed or mixed via direct sequential polymerization on a ∼50-250 nm, and perhaps finer, scale. Thus, the results provide visual confirmation that, to accommodate the growth of the HDPE phase, the first-grown iPP phase fracture extends through the primary grains themselves as the grains expand with new polymer. We expect that the demonstration of nearly effortless quantitative production of small polyolefin spheres, potentially with controlled surface roughness, as well as the commingling of immiscible polyolefins achieved on this fine scale in the nascent granules, could spawn new creative opportunities for material design.

To measure N-acetyl aspartyl glutamate (NAAG) and N-acetyl aspartate (NAA) concentrations in visual cortex activated by a continuous stimulation in a 3 T field. NAAG and NAA spectra were obtained with MEGA-PRESS pulse sequence (TE/TR = 140/2000 ms; δONNAAG/δOFFNAAG = 4.61/4.15 ppm; δONNAA/δOFFNAA = 4.84/4.38 ppm) in 14 healthy volunteers at rest and upon stimulation by a radial checkerboard flickering at a frequency of 8 Hz. Spectra of all subjects were frequency and phase aligned and then averaged. Additionally, to obtain the time-dependency data, spectra were divided into time sections of 64 s each. The intensities of NAA, NAAG and lactate + macromolecular (Lac + MM) signals were defined by integration of the real part of spectra. The heights of the central resonance of NAAG and NAA signals were measured. The NAAG and NAA concentrations, measured with 2.5% and 0.5% error, respectively, were unaffected by visual activation. A significant increase in the Lac + MM signal by ~ 12% is clearly observed. No stimulation-induced time dependency was found for NAAG or NAA, while the increase in Lac + MM was gradual. The concentration values in visual cortex are in good agreement with the 7 T MRS measurements: [NAAG] = 1.55 mM, [NAA] = 11.95 mM. The MEGA-PRESS pulse sequence together with the spectral preprocessing techniques allowed to demonstrate that the concentrations of NAAG and NAA in the visual cortex remain constant during continuous visual stimulation within the margin of error. An increase in the lactate signal intensity signifies the activation of the anaerobic glycolysis in activated visual cortex.

As an essential precursor, K2MnF6 plays an important role in the preparation of Mn4+-activated fluoride materials, but its deterioration in pure water hampers development of a green route. Herein, ...

Transparent ceramics are at the heart of modern magneto-optical materials providing promising opportunities for Faraday isolators. 1.0 at% RE:Tb3Ga5O12 (rare earth (RE) = Pr, Tm, Dy) transparent ceramics were successfully prepared by air sintering and sequential HIP technique using the coprecipitated powders as the raw material. All the powders have shown to be a pure cubic terbium gallium garnet (TGG) phase and exhibit good dispersion. Additionally, a change could not be observed in particle shape with the different doped ions. After the two-step sintering, all the obtained ceramics have good optical quality, and the in-line transmittances at 1070 nm are higher than 80%. Moreover, no secondary phase can be detected from the microstructures. However, the pores which remain entrapped in the ceramics can be noted. The Verdet constant of ceramic samples is optimized by RE doping, and the Verdet constant at 632.8 nm is about −143 rad·T−1·m−1, which is about 5% higher than that of TGG ceramics. Finally, the thermo-optical properties of 1.0 at% RE:TGG transparent ceramics are compared. The annealed TGG ceramic showed the best thermo-optical properties, and the thermally induced depolarization of 1.0 at% Ce:TGG and 1.0 at% Tm:TGG was inferior to that of annealed TGG ceramic.

The study of influence of the skin effect, which occurs when charging metal samples with hydrogen, on the thermal desorption spectra (TDS) is carried out. The main goal of the study was to identify the causes of possible errors in determining the binding energies of hydrogen. The effects arising at different rates of the increase TDS temperature are investigated. The study was carried out analytically and numerically by means of FEM modeling. The standard Fick model is taken for modeling the hydrogen transport model in order to gain a simple explanation of the effects. The skin effect was found to lead to appearance of an extra peak on the TDS. Deciphering the TDS using the Choo-Lee plot results in dependence of the activation energy or hydrogen binding energy calculated by the Kissenger formula on the range of temperature rates in which the TDS experiment was performed.

The paper presents the adhesive strength measurements of the Ni–Cu surface alloy formed on a copper substrate at a different thickness of the transition layer. The formation of the surface alloy is provided by the low-energy high-current electron beam of a microsecond duration; the different thickness of the transition layer is varied by the thickness of the nickel film sputtered. The multiple deposition-irradiation process is performed during one vacuum cycle. It is found that the cross-section of the film (Ni)-substrate (Cu) interface is rather developed and curved. The transition layer thickness reduces with increasing thickness of the deposited nickel film. Scratch testing shows that the adhesive strength of the Ni–Cu surface alloy obtained by using the low-energy high-current electron beam, is higher than that of the sputter-deposited surface alloy. The highest adhesion is observed for the Ni–Cu surface alloy obtained by the nickel film deposition 0.125 μm thick. In this case, the crack formation and localized film delamination occur under the critical loads of 15 and 17 N, respectively. Nevertheless, a complete delamination of the surface alloy is not observed.

We study the long-run effects of Russia’s anti-alcohol campaign, which dramatically altered the relative supply of hard and light alcohol in the late 1980s. We find that this policy shifted young men’s long-run preferences from hard to light alcohol decades later, and we estimate the age at which consumers form their tastes. We show that the large beer market expansion in the late 1990s had similar effects on young consumers’ tastes, while older consumers’ tastes remained largely unchanged. We then link these long-run changes in alcohol consumption patterns to changes in male mortality. The shift from hard to light alcohol reduced incidences of binge drinking substantially, leading to fewer alcohol-related deaths. We conclude that the resulting large cohort differences in current alcohol consumption shares explain a significant part of the recent decrease in male mortality. Simulations suggest that mortality will continue to decrease by another 23 percent over the next 20 years due to persistent changes in consumer tastes. Program impact evaluations that focus only on contemporaneous effects can therefore severely underestimate the total effect of such public policies that change preferences for goods. (JEL D12, H25, H31, I12, I18, L66, P36)

A specialized method for synthesizing conceptual technical solutions for energy converters (EC) is considered using the example of carbon dioxide-based technological lasers. The method is based on a new information model of the physical principle of action (PPA). The results of the research were presented in the form of a guiding methodological material (GMM), consisting of four parts.

The poor water resistance property of a commercial Mn4+-activated narrow-band red-emitting fluoride phosphor restricts its promising applications in high-performance white LEDs and wide-gamut displays. Herein, we develop a structural rigidity-enhancing strategy using a novel KHF2:Mn4+ precursor as a Mn source to construct a proton-containing water-resistant phosphor K2(H)TiF6:Mn4+ (KHTFM). The parasitic [HMnF6]- complexes in the interstitial site from the fall off the KHF2:Mn4+ are also transferred to the K2TiF6 host by ion exchange to form KHTFM with rigid bonding networks, improving the water resistance and thermostability of the sample. The KHTFM sample retains at least 92% of the original emission value after 180 min of water immersion, while the non-water-resistant K2TiF6:Mn4+(KTFM) phosphor maintains only 23%. Therefore, these findings not only illustrate the effect of protons on fluoride but also provide a novel insight into commercial water-resistant fluoride phosphors.

The properties of interfaces in the heterostructures which frequently govern their operation are of particular importance for the devices containing heterostructures as active elements. Any further improving of the characteristics of semiconductor devices is impossible without a detail analysis of the processes occurring at the interfaces of heterojunctions. At the same time, the results largely depend on the purity of the starting materials and the technology of layer manufacturing. Moreover, the requirements to the composition and distribution of the impurity steadily get stringent. Therefore, the requirements regarding the methods of the impurity control and carrier distribution also become tougher both in the stage of laboratory development of the structure and in various stages of manufacturing of semiconductor devices. Electrochemical capacitance-voltage profiling is distinguished among the methods of electrical diagnostics of semiconductors by the absence of special preparation of the structures and deposition of the contacts to perform measurements, thus providing for gaining information not only about the impurity distribution but also about the distribution of free carriers. The goal of this work is to perform precise measurements of the profiles of free carrier distribution in semiconductor structures of different types, and demonstrate the measuring capabilities of a modern technique for concentration distribution diagnostics, i.e., electrochemical capacitance-voltage profiling. The method allows verification of the layer thickness in semiconductor heterostructures and provide a useful and informative feedback to technologists. To increase the resolution of the method and broad up the range of available test frequencies, a standard electrochemical profiler has been modified. Mapping data for GaAs substrate structure, the profiles of the concentration distribution of the majority charge carriers in SiC structures, GaAs structure with a p – n junction, pHEMT heterostructure, GaN heterostructure with multiple quantum wells, and in a silicon-based solar cell heterostructure are presented. The obtained results can be used to analyze the physical properties and phenomena in semiconductor devices with quantum-sized layers, as well as to improve and refine the parameters of existing electronic devices.

This article presents the results of studies of the activity of radionuclides in peat-bog profiles of the European subarctic of Russia. Two peat profiles were collected in different areas of the Arkhangelsk region. The peat cores were used to determine 210Pb, 137Cs, 241Am, 239Pu, 240Pu, 238U, and 234U content. To estimate the relationship between radionuclide activity and physicochemical parameters of peat, the content of organic matter, water-soluble salts, carbonates and ash, and the pH of aqueous and salt extracts were studied. Radionuclide activity concentrations in peat samples were measured using inductively coupled plasma mass spectrometry (ICP-MS), low-background semiconductor gamma spectrometry with a high-purity germanium (HPGe) detector, and alpha spectrometry. The 210Pb chronology of peat cores was studied using a constant flow model based on the Monte Carlo simulation method. Comparison of 210Pb dating data showed that the position of the maximum activity peaks of anthropogenic radionuclides shifted along the peat profile. This is probably due to the relative mobility of different radionuclides in the peat massif. Measurement of the atomic ratio 240Pu/239Pu showed that the main sources of pollution in the peatlands of the European subarctic of Russia are global fallout from atmospheric tests from the 1950s through 1980 and fallout from the Chernobyl nuclear accident in 1986. This study shows that a complex of radioactive isotopes in peat deposits can provide valuable information on the environmental pollution loads of subarctic territories.

Semiconductor nanowires are unique materials for studying nanoscale phenomena; the possibility of forming silicon nanowires on bulk silicon-on-insulator substrates in a top-down process ensures complete incorporation of this technology into integrated electronic systems. In addition, the use of ferromagnetic contacts in combination with the high quality of ferromagnetic–semiconductor interfaces open up prospects for the use of such structures in spintronics devices, in particular, spin transistors. A simple approach is proposed to create semiconductor nanowire-based active devices, specifically, bottom-gate Schottky-barrier field-effect transistors with a metal (Fe) source and drain synthesized on a silicon-on-insulator substrate and the transport characteristics of the designed transistors are investigated.

The paper presents new data on concentrations and fluxes of organic carbon, iron, and manganese in waters of the mouth area of the Northern Dvina River. The work was conducted within the project “Northern Dvina River Marginal Filter Observatory” from May 2015 to May 2019 with monthly collection of water samples. Systematic determinations of the concentrations of the main carrier elements of many trace elements in dissolved and particulate forms were used to establish the average weighted of Corg, Fe, and Mn concentrations. The results of 4 years of systematic investigations established the main regularities of seasonal variations of dissolved and particulate forms of element concentrations and the relationships between. Significant variations were observed not only between concentrations but also between fluxes of elements in both forms. However, more than half the annual fluxes of all elements in all years studied was transported to the sea in the spring flood period. The results also demonstrated significant variations between element concentrations and their fluxes in different years. This is unsurprising, since even during the 4 years of investigations, the difference between water runoff and SPM fluxes in different years was up to, respectively, 1.4 and 2.6 times.

Ho2O3 transparent ceramics were fabricated by vacuum pre-sintering combined with hot isostatic pressing (HIP) post-treatment at relatively low temperature from high-purity Ho2O3 powder calcined at 1000 °C for 4 h. The optimal Ho2O3 ceramic sample prepared by vacuum pre-sintering at 1250 °C and HIP post-treating at 1450 °C has a dense microstructure with average grain size of 0.77 μm, and the in-line transmittances reach 80.7 % at 1550 nm and 76.7 % at 1064 nm. The effect of air annealing on the optical quality of Ho2O3 ceramics was studied, and the existence of compressed pores in the HIP-ed Ho2O3 ceramics was confirmed. The Verdet constants of Ho2O3 ceramics were measured to be -47.4 rad/(T m at 1064 nm and -15.4 rad/(T m at 1561 nm. High transmittance and large Verdet constant in the wavelength regions 1–1.07 μm, 1.3–1.5 μm make Ho2O3 transparent ceramics promising for magneto-optical devices for lasers based on Yb-, Nd-doped materials and telecom lasers. © 2020 Elsevier Ltd 19-52-53014; Chinese Academy of Sciences, CAS: QYZDB-SSW-JSC022; Russian Science Foundation, RSF: 18-13-00355; National Key Research and Development Program of China, NKRDPC: 2017YFB0310500 This work was supported by the National Key R&D Program of China (Grant No. 2017YFB0310500 ), the Special Exchange Program of Chinese Academy of Sciences (Plan B) , the key research project of the frontier science of the Chinese Academy of Sciences (No. QYZDB-SSW-JSC022 ), partially by the Research Project of the Russian Science Foundation (No. 18-13-00355 ) and Verdet constant measurements was done under NSFC-RFBR Cooperative Research Projects Grant 19-52-53014.

Environmentally safe fuel combustion is an actual worldwide problem. The alternative technology of combustion in fluidized bed of catalyst was developed in the Boreskov Institute of Catalysis. The technology allows one to conduct the process at 400–700 оC and significantly reduce outlet concentrations of toxic compounds. However, the use of sulfur oils as fuel demands solving a problem of the decreasing the outlet SO2 concentration because the oils contain small amount of ash to absorb SO2. The work is devoted to study features of sulfur light oil and high-sulfur heavy oil combustion in the fluidized bed of the Al–Cu–Cr-oxide catalyst. Reduction of SO2 emission at conserving oxidation degree of oils within range of 99.5–99.8% might be reached by using a non-isothermal temperature profile in the reactor as well as a use of CaCO3 or CaO at Ca/S > 2 to absorb sulfur oxides. The non-isothermal temperature profile in the reactor consisted of an oxidation zone with the temperature in the fluidized bed of 700 оC and a catalytic oxidation of SO2 to SO3 zone with equilibrium shift to reducing SO2 concentration because of the temperature change from 700 оC to 585 оC.

Hydrogen bonding plays an essential role in biological processes by stabilizing proteins and lipid structures as well as controlling the speed of enzyme catalyzed reactions. Dimethyl sulfoxide-water (DMSO-H2O) solution serves as a classical model system by which the direct and indirect effects of hydrogen bonding between water hydrogens and the sulfoxide functional group can be explored. The complex transition from self-bonding to heterogeneous bonding is important, and multiple spectroscopic approaches are needed to provide a detailed assessment of those interactions. In this report, for the first time, hyper-Raman scattering was successfully employed to investigate molecular interactions in DMSO-H2O system. We measured the improper blueshift of the C–S and C–H stretching modes of DMSO caused by partial charge transfer and enhanced bond polarization. By detecting differences in the frequency shifts of C–S and C–H modes for low DMSO concentrations (

The features of quenching on the line of continuous heat treatment (CHT) of wide (2400 mm wide) cladding sheets made of high-strength aluminum alloy B95p.ch. are given. The investigations of the structure, corrosion resistance and mechanical properties in tension at different temperatures shown that the technology of heat treatment, including hardening on the CHT line and subsequent artificial two-stage aging according to the T2 modes of sheets, made it possible to provide a uniform characteristic structure, the surface quality and level of mechanical properties necessary for sheathing sheets along the width of the sheet and in different directions of rolling that meets the requirements of the aviation industry standard.

Objective: The goal of this study was to examine the prevalence of anti-core+1 in “naive” patients with chronic hepatitis C and different stages of liver fibrosis infected by HCV subtypes 1b and 3a.Materials and methods: A total of 86 “naive” patients (37 men and 49 women) with CHC observed in the Botkin infectious disease hospital in 2017, were included in this study. The average age was 50,7±2,7. Laboratory tests included ALT and bilirubin. In 53 patients, the fibrosis stage in the liver tissue was evaluated by the TE method using Fibroscan (Echosens, France). The presence of antibodies to the core+1 protein in blood serum samples was determined by the “inhouse” indirect ELISA method using synthetic peptides F10 and F13, which amino acid sequences correspond to the antigenic determinants of core+1 protein of the HCV subtypes 1b and 3a, respectively.Results: In total, anti-core + 1 were detected in 27 (31,4%) subjects. It has been shown that the detection rate of anticore+1 does not depend on the HCV subtype. The study has indicated no statistically significant dependence between the presence of anti-core+1 and biochemical activity es of the infectious process (ALT, bilirubin). Anti-core+1 were detected in patients with all stages of fibrosis, however, the detection rate of anti-core+1 was statistically higher in patients with stage F4 fibrosis than in patients without liver fibrosis.Conclusion: The obtained results suggest a possible role of the core+1 protein in the development of fibrosis. In the natural course of HCV infection, the detection of anti-core+1 can be considered as a prognostic marker for the progression of fibrosis in the liver tissue.

Nanocomposite Fe–Al and Cu–Fe–Al oxide catalysts are studied in the CO oxidation reaction. It is shown that the introduction of copper leads to a more than two orders of magnitude increase in the reaction rate. The most active catalyst is a nanocomposite containing 5 wt % CuO, 78 wt % Fe2O3, and 17 wt % Al2O3. According to X-ray diffraction analysis, the catalysts consist of hematite nanoparticles, α-Fe2O3, and amorphous alumina. Copper is in a highly dispersed state to form CuO and CuFeOx clusters. Results of in situ X‑ray absorption spectroscopy studies suggest that the reduction of copper from Cu2+ to Cu1+ and Cu0 in a CO stream begins at a temperature of 200–250°C; at 400–600°C, copper is mostly in the metallic state; the Fe3O4 → FeO → Fe reduction begins at 400–500°С. In a stoichiometric mixture of CO and O2, Fe3+ does not undergo reduction; the reduction of copper oxide to metal occurs at temperatures above 400°C. In the presence of excess oxygen in a temperature range of 100–600°C, no changes in the chemical state of the catalysts are detected. The mechanism of CO oxidation in the presence of Cu–Fe–Al nanocomposites is proposed.