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A potassium salt of the N2S2O2-coordination Fe(III) anion K[Fe(5Cl-thsa)2] (1) (5Cl-thsa - 5-chlorosalicylaldehyde thiosemicarbazone) is synthesized and characterized structurally and magnetically over a wide temperature range. Two polymorphs of salt 1 characterized by the common 2D polymer nature and assigned to the same orthorhombic Pbcn space group have been identified. The molecular structure of the minor polymorph of 1 was solved and refined at 100, 250, and 300 K is shown to correspond to the LS configuration. The dominant polymorph of 1 features K+ cations disordered over a few crystallographic sites, while the minor polymorph includes fully ordered K+ cations. The major polymorph exhibits a complete three-step cooperative spin-crossover transition both in the heating and cooling modes: The first step occurs in a temperature range from 2 to 50 K; the second abrupt hysteretic step occurs from 200 to 250 K with T1/2 = 230 K and a 6 K hysteresis loop. The third gradual step occurs from 250 to 440 K. According to 57Fe Mossbauer, XRPD, and EXAFS data, the spin-crossover transition for the dominant polymorph is quite peculiar. Indeed, the increase in the HS concentration by 57% at the second step does not result in the expected significant increase in the iron(III)-ligand bond lengths. In addition, the final step of the spin conversion (ΔγHS = 26%) is associated with a structural phase transition with a symmetry lowering from the orthorhombic (Pbcn) to the monoclinic (P21/n) space group. This nontrivial phenomenon was investigated in detail by applying magnetization measurements, electron spin resonance, 57Fe Mossbauer spectroscopy, and DFT calculations. These results provide a new platform for understanding the multistep spin-crossover character in the Fe(III) thsa-complexes and related compounds.

Three tetraphenylborates of mononuclear Mn(III) cation complexes with hexadentate ligands, the products of the reaction between a N,N'-bis(3-aminopropyl)ethylenediamine and salicylaldehydes with the different haloid substitutions at the 5 or 3,5 positions, have been synthesized: [Mn(5-F-sal-N-1,5,8,12)]BPh4 (1), [Mn(3,5-diCl-sal-N-1,5,8,12)]BPh4 (2) and [Mn(3,5-Br,Cl-sal-N-1,5,8,12)]BPh4 (3). Their crystal structure, dielectric constant (ϵ) and magnetic properties have been studied. Ligand substituents have a dramatic effect on the structure and magnetic properties of the complexes. With decreasing temperature, the complex (1) shows a gradual spin crossover from the high-spin state (HS) to the HS:LS intermediate phase, followed by an abrupt transition to the low-spin state (LS) without changing the crystal symmetry. The complexes 2 and 3 are isostructural, but have fundamentally different properties. Complex 2 demonstrates two structural phase transitions related to sharp spin crossovers from the HS to the HS:LS intermediate phase at 137 K and from the intermediate phase to the LS at 87 K, while complex 3 exhibits only one spin transition from the HS to the HS:LS intermediate phase at 83 K.

Covering loess-like loams are widespread in the Chuvash Republic and serve as parent rocks. They are heterogeneous both in the course and in the depth of occurrence. A distinctive feature of loess like loams from other overlying quaternary deposits is a sharp predominance in the granulometric composition of coarse dust fractions ranging in size from 0.05 to 0.01 mm, the content of which is 40% or more. Their granulometric composition varies from light loamy to clayey. Loess like loams, due to the peculiarities of their granulometric composition, have relatively good water permeability and moisture capacity and are superior to original loamy and clay parent rocks of the Permian and Jurassic systems in terms of these parameters. The content of moving forms of phosphorus and potassium (according to Kirsanov) in loess like loams is from 15 to 75 mg/kg, of exchange potassium - from 20 to 105 mg/kg. The soils formed based on them have a well-defined profile, the genetic horizons of which are easily diagnosed in the soil section. Because soils formed on loess like loams have well-developed genetic horizons, clearly manifested features of soil formation peculiar to each soil type, they occupy a central subtype and are diagnosed as typical. However, soils formed on loess-like loams and clays have low erosion resistance and marked as erosion threatening on soil maps.

The strong fascination exerted by the binary compound of FeSe demands reliable engineering protocols and more effective approaches towards inducing superconductivity in FeSe thin films. Our study addresses the peculiarities in pulsed laser deposition which determine FeSe thin film growth and focuses on the film/substrate interface, the tendency for domain matching epitaxial growth but also the disadvantage of chemical heterogeneity. We propose that homogenization of the substrate surface improves the control of stoichiometry, texture, and nanostrain in a way that favors superconductivity even in ultrathin FeSe films. The controlled interface in FeSe/Fe/MgO demonstrates the proof-of-principle., Submitted

We report on an electron-spin resonance study of nuclear-polarized phases of hydrogen atoms embedded in solid H $$_{2}$$ films at temperatures 0.1–1.5 K and a high magnetic field of 4.6 T. The H atoms in solid H $$_{2}$$ were generated by two different dissociation techniques: a cryogenic rf-discharge and bombardment by 5.7 keV electrons via tritium decay. In both studies, we observed a build-up of a spontaneous nuclear-polarized phase (SNPP, p=0.35) at temperatures below $$\sim $$ 0.8 K similar to that reported in our previous work. We were also able to create a highly nuclear-polarized phase (HNPP, $$p\simeq $$ 0.75) using Dynamic Nuclear Polarization for samples exposed to a cryogenic rf discharge, whereas we failed to obtain this phase for the samples bombarded by 5.7 keV electrons. We suggest that failing to achieve the HNPP in the samples exposed to high-energy electrons released during tritium decay may be explained by an effect of faster nuclear relaxation stimulated by electrons bombarding the H $$_{2}$$ matrix and rapidly relaxing centers in the film substrate created during accumulation of H atoms in solid H $$_{2}$$ .

Levulinic acid (LA) is one of the substances, which can be obtained from cellulosic biomass via acid hydrolysis and serves as a precursor in the synthesis of gamma-valerolactone (GVL) – platform chemical for so-called valeric fuels. This work is devoted to the study of catalytic conversion of LA to GVL using mono- (Ru) and bimetallic (Ru-Co) catalysts based on ruthenium-containing nanoparticles immobilized in hyper-crosslinked polystyrene (HPS). It was shown that RuO2 nanoparticles are an active phase of HPS-based Ru catalysts, which allow nearly 100 % yield of GVL at 120 °C and 2 MPa of hydrogen partial pressure for the reaction time 60 min. Introduction of cobalt in catalyst composition in a proper amount (Ru-to-Co weight ratio is 30) was found to result in Ru redistribution inside the polymeric support and, in turn, to the increase of reaction rate of LA hydrogenation.

The article presents studies on the evaluation of the commercial qualities of the Lena sturgeon when using the feed additive "Reasil ® Humic Health" in its diet. The obtained data allow us to conclude that the addition of the Reasil ® Humic Health feed additive based on unmodified microporous humic acids from leonardite to the granulated compound feed has a positive effect on the growth and development of the Lena sturgeon and increases their yield of edible body parts by 1.74 %, while not adversely affecting the anatomical state of the internal organs of the fish and contributing to the development of the internal organs of the Lena sturgeon. The results of the chemical analysis allow us to say about the intensive metabolism in the body of fish that received a feed additive and the deposition of a larger amount of dry matter in their muscle tissue.

Abstract A procedure is proposed for synthesizing monometallic (Co, Pd) and bimetallic Co–Pd nanoparticles immobilized in a carbon support based on pyrolyzed chitosan. A feature of the procedure is the simultaneous formation of metal nanoparticles and a carbon support during the heat treatment of a precursor based on a joint solution of a polymer and metal compounds under the effect of IR radiation. The phase composition, morphology of samples, and structural features of the carbon support are shown, depending on the nature of the metals that are used.

To solve the question about the oligomeric state of wild-type CBS-pyrophosphatase (CBS-PPase) from D. hafniense, this enzyme has been studied using two independent structural methods: small-angle X-ray scattering (SAXS) and cryogenic transmission electron microscopy (cryoTEM). The formation of stable high-order structures (large helical associates) in a concentrated protein solution has been observed for the first time. It is also shown for the first time that the formation of these structures is a reversible process and the protein passes to the tetramer form (in which it usually exists in diluted solutions) at ligand attachment. The obtained results are important for understanding the functional features of CBS-PPase (in particular, gaining insight into the pathogenesis of some diseases).

A process for the preparation of premixes using a two-stage dosing and mixing is described. Microcomponents are dosed and mixed at the first stage with the preparation of preliminary mixtures (mineral and vitamin), while the final dosing and mixing of the components with filler and are performed at the second stage. Three samples of water-soluble premixes for laying hens (sample no. 1 with feed vitamins and trace element sulfates; sample no. 2 - using food vitamins and organic forms of trace elements; sample no. 3 - using food vitamins and trace element sulfates) have been developed and prepared.

A new principle for supplying volatile precursors to MOCVD gas-phase chemical deposition systems is proposed, based on a two-stage evaporation of an organic solution of precursors from a soaked cotton thread, which passes sequentially through the zones of evaporation of the solvent and precursors. The technological capabilities of TSF-MOCVD (Thread-Solution Feed MOCVD) are demonstrated based on examples of obtaining thin epitaxial films of СеО2, h-LuFeO3 and thin-film heterostructures β-Fe2O3/h-LuFeO3. The results of studying the obtained films by X-ray diffraction, energy dispersive X-rayanalysis, and high- and low-resolution transmission microscopy are presented. Using the TSF module, one can finely vary the crystallisation conditions, obtaining coatings of the required degree of crystallinity, as evidenced by the obtained dependences of the integral width of the h-LuFeO3 reflection on the film growth rate. Based on the TEM and XRD data, it was concluded that β-Fe2O3 grows epitaxially over the h-LuFeO3 layer. Thus, using TSF-MOCVD, one can flexibly change the composition of layered heterostructures and obtain highly crystalline epitaxial films with a clear interface in a continuous deposition process

Vacuum heat treatment of mechanically alloyed powders of boron and aluminium leads to the formation of a metastable Al-rich phase, which can be quenched. Its structure, composition and thermal stability are established. With the chemical formula Al1.28B the rhombohedral phase is unusually rich in Al. The parameters of the unit cell determined from X-ray powder diffraction are a = 18.3464 (19), c = 8.9241 (9) Å, V = 2601.3 (6) Å3, space group R 3. It is stable on heating to 630°C. It is suggested that this phase is an important intermediate step in the formation of AlB2 and, eventually, of other borides; its nucleation and thermal stability are explained by high elastic energy hindering the formation of equilibrium phases at low temperatures.

A novel sodium bismuth oxo-cuprate phosphate chloride, Na6Cu7BiO4(PO4)4[Cl2.23(OH)0.77], containing square-kagome layers of Cu2+ has been synthesized by hydrothermal techniques. The compound crystallizes in the tetragonal space group P4/nmm, a = 10.0176(4), c = 10.8545(6), Z = 2, V = 1089.3(1) A3, R1 = 0.021, wR = 0.053, S = 1.32. Its composite crystal structure includes [O4Cu6Bi]7+ layers, which are formed by the clusters of oxygen-centered tetrahedra [OCu3Bi]. These positively charged two periodic fragments are intercalated in a negatively charged [CuNa6Cl3(PO4)4]7- matrix built by Na-centered polyhedra, PO4 tetrahedra, and CuO4Cl pyramids. The composite character of the crystal structure of Na6Cu7BiO4(PO4)4[Cl2.23(OH)0.77], as well as the way of its self-assembly, are discussed in close connection with the sulfohalite Na6ClF(SO4)2 salt. It is shown that the "host-guest" model of the formation of the tetragonal Na6Cu7BiO4(PO4)4[Cl2.23(OH)0.77] phase is due to the group-subgroup symmetry relation with the cubic crystal structure of mineral sulfohalite and is also supported by the crystallization condition in excess sodium chloride. The magnetic subsystem of Na6Cu7BiO4(PO4)4[Cl2.23(OH)0.77] is represented by a dense square-kagome network of 2Cu1 and 4Cu2 ions, decorated with weakly bonded Cu3 ions. Measurements of magnetization and heat capacity indicate the absence of long-range order up to 2 K, which makes this compound a candidate for a highly demanded spin liquid.

A novel modification of the KCoPO4, δ-phase has been prepared by hydrothermal synthesis at 553 K. The compound crystallizes in the orthorhombic system with the unit-cell parameters a = 8.5031(8), b = 10.2830(5), c = 54.170(4) A. The crystal structure was determined based on synchrotron low-temperature single-crystal X-ray diffraction data obtained from an inversion twin in the space group P212121 and refined to R = 0.077 for 5156 reflections with I > 3σ(I). The δ-KCoPO4 possesses a new structure type which is based on a framework built from sharing vertices Co- and P-centered tetrahedra. The {CoPO4-}∞ construction of tetrahedra may be described as assembled from networks formed by two topologically diverse six-membered rings of tetrahedra stacked together through vertex-bridging contacts along the a axis. The ratio of the (UUUDDD) and (UUDUDD) rings, where (U) and (D) denote the orientation of the tetrahedra in the six-membered rings up and down relative to the plane grids, is equal to 5:1. The (UUDUDD) rings form bands parallel to the [010] direction each surrounded from both sides along the c axis by slabs of five ribbons width having alternative (UUUDDD) topology. Open in the [100] direction channels incorporate K+ ions; this structural feature permits to suppose ion-conductive and/or electrochemical properties of the title compound. The possible mechanism of the δ → γ phase transition is discussed on the basis of the crystal chemical analysis of the KCoPO4 polymorphs. The title compound orders magnetically at TN = 24.8 K.

A spectrometric stand for measuring the energy resolution of unpackaged single-channel silicon planar detectors has been developed and manufactured. The developed spectrometric stand makes it possible to reject detectors with unsatisfactory spectrometric characteristics at an early stage of manufacturing the detecting modules. Also, a technique has been developed for studying the spectrometric characteristics of unpackaged silicon detectors intended for the manufacture of detecting modules for ionizing radiation for various purposes.

The article presents the results of the use of humic acids in the cultivation of Lena sturgeon in closed water supply installations. The use of "Reasil ® Humic Health" at a concentration of 1.5 g per 1.0 kg of mixed feed in fish feeding contributed to an increase in the productivity of Lena sturgeon by 6 %. Humic acids have a wide range of biological activity, affecting the metabolic processes in the body of animals and humans. The introduction of humic acids into the diet of sturgeon helps to increase productivity, due to the ability to stimulate the production of enzymes, reduces feed costs by 1 kg of growth. The use of Reasil ® Humic Health feed additive based on unmodified microporous humic acids from Leonardite in the diet of sturgeon contributes to an increase in profitability by 9.4 %.

The unique family of coordination polymers [Ln4(OH)2(piv)10(H2O)2]∞ of 11 lanthanides (Ln = La-Er) has been prepared by a simple solution method based on controlled hydrolysis. The ribbon-like polymeric structure consisting of connected tetranuclear clusters and supported by pivalate ligands and a framework of H-bonds has been revealed by single-crystal X-ray diffraction. While the compounds demonstrate similar PXRD patterns and unit cell parameters, the joint single-crystal XRD and pair distribution function data suggest the significant local structure change along the lanthanide series. The compounds exist as two packing polymorphs (α and β) with similar ribbon geometry, but different supramolecular arrangement of the ribbons. Dehydration of either polymorph does not disturb the tetranuclear core but leads to a translational symmetry loss along the ribbon and a transformation of the 3D-ordered crystal into a 2D-ordered mesostructure. Rehydration of the mesostructure leads to the β polymorph (except La and Ce), allowing the deliberate switching between the polymorphs via dehydration-rehydration evidenced by means of powder X-ray diffraction, pair distribution function analysis, and density functional theory calculations. Ab initio calculations reveal significant magnetic anisotropy of Ln3+ ions with ferro- and antiferromagnetic interactions within tetranuclear [Ln4(OH)2(piv)10(H2O)2] species. Magnetic susceptibility measurements demonstrated antiferromagnetic coupling, slow magnetic relaxation for Dy, Ho, and Er complexes, and field-induced single-chain magnetism for the Dy compound.

The review article presents data on extracellular vesicles (EV), bilayer phospholipid membrane structures which are secreted by different cell types and contain proteins, lipids, and nucleic acids. The features of their structure, biogenesis, and mechanisms of interaction with the recipient cell are considered. The properties of extracellular vesicles of embryonic stem cells (ESCs) and their role in the regulation of developmental processes are also considered. Special attention is paid to the vesicles of induced pluripotent stem cells (iPSCs), their role in maintaining pluripotency, and the properties of the vesicles of cells obtained during the directed differentiation of iPSCs.

Herein, the effect of various treatments subjected to FAU zeolites to introduce mesoporosity has been examined on their efficiency as catalyst in the cyclisation of O-aryl 3-arylpropynoic acid ester to its corresponding coumarin. The addition of bio-sourced lignin residues in the alkaline desilication treatment induced the generation of supplementary mesoporosity, thus offering an optimal micro- and mesopores combination with respect to targeted activity and selectivity. The so-called bio-sourced secondary template (BSST) concept in the design of zeolite-based catalysts could be assessed. The use of renewable wood feedstocks can therefore be a valuable strategy for the zeolite post-modification, thus for the design of porous zeolite catalysts.

In this study, we developed a surface coil with a meanderline shape for nuclear magnetic resonance (NMR) combined with a Fabry–Perot resonator (FPR) for millimeter-wave band electron-spin resonance (ESR). Our goal was to perform both NMR and ESR measurements with high sensitivity, in particular for thin samples, such as a silicon wafer. We measured NMR signals using a variety of meanderline coil shapes and determined the optimal turn number of the meanderline as well as the clearance length between the lines. The FPR consisted of spherical and flat mirrors, where the latter was constructed of a thin gold layer with the meanderline underneath. We observed that the meanderline provided high sensitivity when the gold layer was sufficiently thin at approximately 16 nm. We also measured millimeter-wave ESR from a thin sample of phosphorous-doped silicon with the developed FPR with the meanderline.

A report is given on the main results from the NUCLEON space experiment. The composition and spectrum of cosmic rays is measured in the range of 2 to 500 TeV. Spectra of particular nuclei, including nickel and secondary nuclei, are obtained. The dependence of the ratio between the fluxes of protons and helium nuclei on magnetic rigidity is investigated. A universal knee is found in the magnetic rigidity spectra of different nuclei.

Using deagglomerated nanodiamond particles of 4–5 nm suspended in polydimethylsiloxane (PDMS) we have fabricated fluids demonstrated pronounced electrorheological effect. It has been revealed that the type of functional groups on nanodiamond particle surface plays a crucial role in the behavior of the suspensions under electric field. Suspension of hydrogenated nanodiamonds has demonstrated the most powerful electrorheogical effect. The high values of yield stress of the order of 80–90 Pa have been detected at extremely low concentrations of nanodiamond particles (3–4 wt%). The suspensions has outstanding sedimentation stability: the sedimentation ratio is more than 90% after 30 days. A power law dependence of the yield stress on the electric field, τ ∼ E1.0-1.5 indicates mainly the conduction mechanism of the effect. Suspensions of carboxylated nanodiamonds in PDMS reveal qualitatively different behavior and the electrophoresis occurs. The paper discusses the reasons of different rheological behavior depending on nanodiamond surface functionalization. The prospects of nanodiamonds application as filler for electrorheological fluids have been shown.

—The goal of the work was to study the effect of peptide bioregulation on the mucosal immunity state of elderly patients during the complex treatment of chronic generalized periodontitis. The results were evaluated based on the saliva immunological parameters of 46 patients aged 61–69 years suffering from chronic generalized periodontitis of moderate severity before treatment and 2 months after the completion of treatment with the Vizulingval peptide complex as a peptide bioregulator. The index of oral hygiene and the intensity of gingival inflammation were studied during clinical patient examinations. A decrease in the concentration of proinflammatory cytokines IL-1β, TNF-α, and IL-8 with a simultaneous increase in the IL-10 anti-inflammatory cytokine was noted in the salivary fluid of patients subjected to bioregulatory therapy. The therapy also led to an enhancement of the local immunity of the oral mucosa, which was manifested by an increased synthesis of the secretory immunoglobulin A.

Crystals of Cs6(SO4)3(H3PO4)4belong to the family of alkali metal acid salts that show a high protonic conductivity at relatively low temperatures. Such properties make superprotonic crystals an excellent choice for the study of the influence of the hydrogen subsystem on the physicochemical properties and promising materials for energy-efficient technologies. Single crystals of Cs6(SO4)3(H3PO4)4were studied by neutron diffraction methods, optical polarization microscopy, scanning electron microscopy and energy-dispersive X-ray spectroscopy. Neutron diffraction studies made it possible to determine the positions of all the atoms with high accuracy, including the H atom on a hydrogen bond characterized by a single-minimum potential, to confirm the chemical composition of the Cs6(SO4)3(H3PO4)4crystals and their cubic symmetry in low- and high-temperature phases, and to draw conclusions about the three-dimensional system of hydrogen bonds, which is fundamentally different in comparison with other superprotonic compounds. Based on the experimental data obtained, crystal transformations with temperature changes are reported, and the stability of the chemical composition is shown.

The mass spectra of negative ions of aqueous solutions of completely neutralized monochloroacetic acid (MCA), dichloroacetic acid (DCA), and trichloroacetic acid (TCA) with a concentration of 0.01 mol/L at 20°C are obtained by the mass spectrographic method of electrospraying electrolyte solutions in vacuum. In all the distributions according to the degree of hydration of the acid residue, the dependence of the ion current intensity on the number of water molecules in the ion current is found. At an acid concentration of 0.01 mol/L, the number of hydrated monochloroacetic and dichloroacetic ions decreases monotonically with the increasing degree of hydration. For a TCA solution, the ion current intensity reaches the maximum of the distribution for two water molecules in the ion.

The article discusses the features of the formation of the leaf surface, photosynthetic potential and yield of tubers, depending on the timing and density of potato planting. The objective of our research was to study photosynthetic activity, yield and quality of potato tubers depending on the density and timing of planting. Field experiments were carried out in the forest-steppe zone of the Trans-Urals in 2014-2017 with potato varieties Rosara (early ripening) and Kuzovok (mid-ripening). The optimal combination of agricultural practices has been established to obtain the planned potato yields with high quality tubers - planting on May 12-15 (Kuzovok varieties according to the scheme 75x27 and 75x19 cm, and Rosara varieties - only 75x19 cm). The optimal planting period provides the greatest photosynthetic potential of potatoes with a thickened planting scheme (4.18-5.45 million m2/ha-days), which, due to the assimilation of 3.9 to 4.4% of photosynthetically active solar radiation, ensures the formation of a crop of tubers 40.2-42.8 t/ha. The fourth term for planting potatoes (June 5-12), reducing the FP by 12.6-21.9% depending on the variety, the PAR efficiency - by 28.4-30.1%, caused a decrease in yield by 6.6-7, 4 t/ha, tuber starch content - by 2.0-2.7% compared to planting on May 12-15. At the same time, the amount of nitrates in tubers increased by 1.93-2.22 times.

This paper presents the results on the development of an alloy in the tellurium - copper - cerium system used for the manufacture of functional coatings using the technologies of supersonic cold gas-dynamic spraying. Coatings from the specified alloy are used for the manufacture of photocathodes of photoelectronic devices operating in the UV spectral region.

New data on parameters of combustion and detonation of two-fuel mixtures of methane and hydrogen with oxygen and air are presented. The data are obtained with variations of both the ration between CH4 and H2 and also the ratio between the fuel components and oxidizer. Results for the critical energy of detonation initiation, characteristic size of detonation cells, detonation velocity, and energy release in detonation waves are included. New information on parameters of combustion and detonation of methane mixtures diluted by water, including situations with gas hydrates, is reported.

Oxide dispersion strengthened steels ODS Eurofer and ODS 13.5Cr-0.3Ti were irradiated with 945 MeV Au ions and 167 MeV Xe ions at room temperature. Beam-induced microstructural changes were analyzed by high-resolution transmission electron microscopy in the region of maximum electronic energy loss of 55 and 30 keV/nm, respectively. In both ODS steels, an increase in the fraction of small oxide inclusions (

We studied 14 samples of gram-negative and gram-positive bacteria, unicellular yeasts and green algae using optical, atomic force and analytical scanning electron microscopy, thermal analysis, gas chromatography, infrared spectroscopy, inductively coupled plasma mass spectrometry and isotope mass spectrometry. In shape, the cells of microorganisms vary from rod-shaped to lenticular and coccoid, in size they range from mesonanometer to micrometer. A strong positive correlation was found between the extreme cell sizes. An admixture of inorganic chemical elements — Mg, Ca, Ba, Na, K, Cu, Zn, P, S, Cl and submicron-sized precipitates of mineral phases — carbonates, phosphate sulfates, hydrogen sulfate phosphates, hydrogen phosphates, halite, kaolinite, was found in the chemical composition of the studied microorganisms, metal alloys of brass composition, baddeleyite. Among the 45 microelements identified in microorganisms, there were 7 essential elements (E), 17 physiogenically active (FA) and 19 abiotic (AB). The total concentration of trace elements ranged from 0.003—0.26 wt. %. The value of the essential coefficient — E / AB — averaged 196 ± 153. Microorganisms were characterized by a mixed fat-protein elemental composition, they contained 14 amino acids belonging to the aliphatic, aromatic, basic, acidic, hydroxyl, imino and sulfur-containing groups. The total amino acid content ranged from 409 to 942 (682 ± 221) mg/g. Up to half of the amino acids were represented by the left (L) and right (D) enantiomers. The degree of racemization (D / L) ranged from 0.01 to 0.37. Yeast and chlorella were characterized by the most isotopically heavy composition of carbon in combination with relatively isotopically light nitrogen. In bacteria, a statistically lighter carbon was found in combination with a much heavier nitrogen. According to a number of properties — the chemical composition of organic matter, microelements, the degree of enrichment with antibiotic elements, the content of amino acids and the degree of their racemization — gram-negative and gram-positive bacteria differed. In general, the studied biological microorganisms were fundamentally different from the abiogenic organic substances found in meteorites and products of modern volcanism regarding their elemental and amino acid composition, carbon and nitrogen isotopes.

A cell for studying the diffusion of therapeutic medical radionuclides into the macrolayer of the carrier sorbent was fabricated using 3D printing. The diffusion of ultramicroquantities of radium and strontium within a layer of watered hydroxyapatite was investigated. The value of the effective diffusion coefficient obtained using a one-dimensional nonstationary model was (1.0 ± 0.4) × 10–8 cm2/s for Ra and (3.0 ± 0.3) × 10–8 cm2/s for Sr.

The standard values (T = 298.15 K) of thermodynamic properties of hexagonal tungsten disulfide 2H-WS2 were calculated from first principles using density functional theory and quasi-harmonic approximation with finite displacements in supercells. Local density approximation was chosen as the exchange-correlation functional and the calculation was performed without Van der Waals corrections. The calculated data are in good agreement, except for the enthalpy of formation, with reliable experimental results, eliminating the discrepancies between the experimental results from different sources and increasing the overall reliability of thermodynamic data for tungsten disulfide. Additionally, the data agreement suggests that greater attention should be paid to experimental studies of the phonon spectrum of 2H-WS2, particularly in the Γ → K region of the low-energy dispersion, where the deviations between the calculation and inelastic neutron scattering are significant. The values of the heat capacity, entropy, and enthalpy of tungsten disulfide are recommended for incorporation into thermodynamic databases and practical application, and the parameters used to calculate these quantities are recommended as initial parameters in firstprinciples studies of the 2H-WS2 properties related to the vibrational spectrum. The calculated value of ∆fH°(2H-WS2, 298.15 K) = –275 ± 0.5 kJ ∙ mole–1 is about 10% below the median of the existing literature data and about 15% below the experimental result accepted as the most reliable. To improve the result, the calculation requires additional attention, for example, by the application of Van der Waals corrections or hybrid approximations to the exchange-correlation functional.

In this study, we demonstrate the synthesis and the investigation of the magnetostatic and magnetodynamic properties of single-domain gallium substituted strontium M-type hexaferrite particles SrFe12−xGaxO19 (x = 1–6). The synthetic approach is based on a precursor preparation via a facile citrate–nitrate auto-combustion method followed by thermal treatment at 1200 °C. The annealing of the porous precursor led to the formation of single-domain hexaferrite particles with mean sizes of 360–560 nm. Introduction of Ga3+ ions up to x = 4 into the hexaferrite structure resulted in an increase of coercivity from 5.1 to 6.4 kOe, and a further increase in gallium concentration led to a decrease in the coercivity. The samples display natural ferromagnetic resonance frequency in the range of 49–57 GHz. Crystal structure refinement reveals that Ga3+ ions preferably occupy 2a, 4f1, 12k, and 2b sites and cause a decrease in the magnetic anisotropy and a modest decrease in the saturation magnetization.

Powders where the γ≈α-Al2O3-nano phases are the priority precursors for catalysts for heterogeneous catalysis with the maximum content of surface 5-coordinated Al centers for Pt attachment. Hydrogenated nano powders (~8 nm) of γ-, γ '-, θ-, κ-Al2O3 soluble in hydrochloric acid were obtained from the processing of aluminum boride powders with an icosahedral structure. Samples, which underwent a step-by-step and single heating of 50-100K heat treatment for 2 hours at temperatures of 570-1470K, were received in quantity of 34. The specific surface area of SВET, m2g-1 was measured by the thermal nitrogen desorption express method of gas chromatography through the GC-1 device. X-ray (phase and coherent), fluorescence and phase chemical-analytical evaluation of the samples were performed. The thermokinetic characteristics of the processes are calculated using the exponential Arrhenius law. Dimensional characteristics of crystallites (10.4-48 nm); specific surface area of powders (213-8.6 m2g-1, SВET); thermokinetic parameters of α-Al2O3 crystallite growth process (V α-Al2O3 - 1.44 10-3 - 6.67 10-3 nm s-1; E α-Al2O3 = 38.7±2.1kJ mol-1; A0 = 0.16±0.0 s-1 along the temperature line 1220-1470K were determined and calculated. The process of dehydration of two OH-groups occurs in the region 570-720K Ea H2O ↑ = 30.5 ± 0.5 kJ mol-1 A0 = 1.33±0.3 s-1. The last group of OH at temperatures of 820 -1070К and a rate of 2.13 10-4 - 4.93 10-4 mol s-1 Ea H2O ↑ = 13.2 ± 0.8 kJ mol-1 A0 = 16.9 ± 0.9 s-1. The activation energy of the phase transition is Ea., γ → α-Al2O3 = 23.9 ± 1.0 kJ mol-1 A0 = 2.01 ± 0.72 s-1 (770-970K) and Ea., γ → α-Al2O3 = 83.5 ± 0.8 kJ mol-1 A0 =(2,05±0,95) 103 s-1 (1070-1170K). It agrees well with the known heat of conversion Eа, γ→α-Al2O3 = 85 kJ mol-1. The TK of γ≈α-Al2O3-nano phases is at 1170K.

The possibility of biodegradation of thermopolymerizable collagen gel (without cultured stem cells) in various concentrations is considered. In an experiment, an unpolymerized collagen gel was injected into the conjunctival cavity during preliminary blepharography. A polymerized collagen gel was obtained by incubating a thermopolymerizing collagen gel at37°C for 30 min until complete polymerization, then the gel was placed on the ocular surface and fixed by blepharography. Collagen gel biodegradation was evaluated at the 1st and 4th hours after surgery. Evaluation criteria: visually by the change in the volume of the plugged conjunctival cavity, leakage of fluid through the intershoot spaces, and also 12 hours after the operation according to the volume of collagen gel remaining in the conjunctival cavity (after removal of blepharoraphic sutures). It was revealed that biodegradation of thermally polarizable collagen gel is carried out by the mechanism of its dehydration regardless of the state of the implanted gel (unpolymerized/polymerized). The volume of the dehydrated collagen framework is directly proportional to its concentration. To increase the biodegradation time of a thermopolarizable collagen gel, it is advisable to develop a method for retaining fluid inside the collagen frame.

The sorption of the actinium(iii) ions as 225,228Ac isotopes on hydroxyapatite (HAP) with various textures was studied. A “reverse” generator using an extraction chromatographic sorbent based on diglycolamide derivative (DGA Resin) was proposed for 228Ac production. The chemical yield of the product was ≥90%. The optimal acidity of the solution during sorption (pH 6–7) and the ratio of solid and liquid phases (20 mg of the sorbent per mL of the solution) were determined in preliminary experiments. The process kinetics is adequately described by pseudo-second-order model. The stationary state is reached rapidly (in 10 min) when a HAP suspension is used, whereas time (20–30 min) is needed for textured samples. The possibility of actinium ion diffusion within the bulk of these samples is shown. The diffusion coefficient of actinium estimated by diffusion in a wet HAP paste layer (one-dimensional model) was (1.0±0.2) • 10−7 cm2 s−1.

Kinetics of catalytic CO oxidation on the surface of metal oxide catalysts decorated with noble metals used as gas-sensing materials for sensors has been studied. The majority of oxide materials (SnO2, Al2O3, zeolite, etc.) decorated with palladium and rhodium shows kinetic features resulting in ambiguous sensor response. Exception is CeO2/ZrO2 decorated with palladium: oxidation rate on this catalyst has a unique dependence on CO concentration. The processes of CO oxidation on inert and chemically reactive supports are described in the context of unified kinetic model. There are two modes of catalyst behavior: below and above a certain concentration threshold, the reaction in each mode has first kinetic order toward CO, while the superposition of these processes can result in efficient “minus one” order of oxidation reaction. The transition of catalyst from one state to another occurs as phase transition observed on change in CO concentration but not catalysts temperature. Oxidation kinetics for each state is described by a small set of parameters characteristic for each catalyst, activation energy for each catalyst is the same at all CO and oxygen concentrations.

Improved mechanical properties of oxide dispersion strengthened (ODS) steels, the advanced materials for the reactor core, are due to the high density of uniformly distributed nanosized oxide inclusions. Transformation of the nanostructure of ODS steels under irradiation determines their stability during operation in the reactor conditions. In this work, three ODS steels are studied: Eurofer ODS, 10Cr ODS, and KP-3 ODS with different alloying systems. In these steels, the chromium content varies from 9 to 14 at %; such alloying elements as V, Ti, Al, W, and Mn are present in different proportions. The effect of irradiation with iron ions up to 3, 6, and 30 dpa at a temperature of 350°C was studied. The radiation-induced changes were analyzed by transmission electron microscopy and atom probe tomography. Although the sizes of oxide inclusions remained almost without change under irradiation, a decrease in their number density was observed in 10Cr ODS and KP-3 ODS steels, while the number density of oxides in Eurofer ODS steel did not change under the irradiation to 30 dpa. On the whole, the strengthening of the ODS steels due to inclusions during the irradiation to 30 dpa at 350°C changed insignificantly, which indicates their radiation resistance and their low propensity for low-temperature radiation strengthening and embrittlement.

The enhanced mechanical properties of oxide dispersion-strengthened (ODS) steels are mainly due to the high density of homogeneously distributed oxide inclusions. It is well known that some alloying elements, such as Ti, V, and Al, play an important role in the formation of oxides/nanoclusters and influence the density and size of these inclusions. In this paper, a wide range of ODS steels containing different alloying elements were studied. The microstructural analysis was performed using transmission electron microscopy and atom probe tomography. Different types of inclusions were found in the steels: oxides of the Y–Ti–O or Y–Al–O types with sizes of ~2–15 nm, and nanoclusters (2–5 nm) enriched in Y, O, and Cr, as well as Ti, V, and Al, when these elements were present in the material. It was shown that oxides made the main contribution to the steel strengthening, while the cluster contribution was comparable with that of oxides only in Austenitic ODS and 14Cr ODS steels.

The radiation resistance of sorbents AG 50 W-X8, Ac resin, and UTEVA resin in contact with hydrochloric solutions under irradiation with 10 MeV electrons in a wide absorbed-dose range up to 2 MGy w...

The results of studying the structure and phase composition of thin-film positive electrodes of a lithium-ion battery based on vanadium oxides are presented. It is shown that initially polycrystalline films contain higher V2O5 and V3O7 oxides, the proportion of which increases with the time of oxygen annealing. As a result of charge–discharge cycling, the higher vanadium oxides are amorphized, while the content of the VO2 and V2O3 phases decreases slightly, and the proportion of VO oxide remains unchanged. These data are in good agreement with the change in the capacity of the films during their cycling, which suggests that the main reason for the decrease in the capacity of the films is the amorphization of the higher vanadium oxides with the highest specific capacity.

The secretome of human mesenchymal stem cells (MSCs) after osteogenic differentiation of FetMSC cells in vitro was obtained to develop tissue engineering technologies for bone tissue. For standard secretome samples a large number of FetMSC cells (7 × 108 cells) were cultured in serum-free conditioned medium (SFCM). All steps of cell processing were performed in the CompacT SelecT automatic system (Sartorius, United Kingdom). The SFCM was concentrated by ultrafiltration, then subjected to dialysis and dried in a vacuum rotary evaporator. The osteoinductive properties of SFCM concentrate (SFCMC) were tested on FetMSC cells by means of adding it to the growth medium at different concentrations. There were no changes in cell morphology during cultivation in the presence of SFCMC. Analysis of the transcription factors Runx2 and YAP1 (markers of osteogenic differentiation) expression using immunofluorescence staining and real-time polymerase chain reaction (RT-PCR) showed an increase in their level of expression in the presence of SFCMC. These findings demonstrate that it is possible to use SFCMC obtained from osteogenic MSCs to induce differentiation of other (undifferentiated) MSCs. The results are useful for the development of cell therapy products for bone restoration based on MSCs secretome.

Protein glycation and the formation of advanced glycation end products (AGEs) play an important role in the pathogenesis of diabetes mellitus (DM) complications, neurodegenerations, and age-related diseases. A model to predict antiglycation activity can reduce the costs and increase the productivity and quality of preclinical screening studies of new compounds. Azolo[5,1-c][1,2,4]triazines and azolo[1,5-a]pyrimidines are well known as biologically active compounds, which additionally have antiglycation properties. A number of 4-hydroxy-4H-azolo-1,4-dihydro[5.1-c]-1,2,4-triazines were selected for designing a prediction model. Azolotriazine derivatives were found to exert an antiglycation effect, inhibiting glycation of bovine serum albumin (BSA) with glucose and specific END fluorescence with equal or greater efficiency as compared with aminoguanidine. The activity range at 1000 μM was estimated at 23.0–71.6% for variously substituted derivatives (30.3 ± 1.2% for aminoguanidine). The highest activity was observed for 4-hydroxy-3-cyano-1,4-dihydro-1,2,4-triazolo[5.1-c]1,2,4-triazine. In all but one compound (aminoguanidine), antiglycation activity correlated with the energy difference ∆(HOMO – LUMO) between the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO); the difference was established by a PM3 semiempirical method. Artificial neural network modeling was used to develop a mathematical model that describes the dependence of antiglycation activity on the calculated energies. The ELUMO and ∆(HOMO – LUMO) energies were found to make the largest contribution to the activity. The model can be used to predict antiglycation activity.

Films were prepared from 2% solutions of biodegradable poly-3-hydroxybutyrate [P(3HB)] and investigated. The polymer was synthesized by the Cupriavidus necator B-10646 bacterium cultivated using various carbon sources (glucose and glycerol of different degrees of purity, containing 0.3 to 17.93% impurities). Glycerol as the substrate influenced molecular-weight properties and crystallinity of the polymer without affecting its temperature characteristics. The P(3HB) specimens synthesized from glycerol had reduced Mw (300–400 kDa) and degree of crystallinity (50–55%) compared to the specimens synthesized from glucose (860 kDa and 76%, respectively). The low-crystallinity P(3HB) specimens, regardless of the degree of purity of glycerol, produced a beneficial effect on the properties of polymer films, which had a better developed folded surface and increased hydrophilicity. The values of the highest roughness (Ra) of the films synthesized from glycerol were 1.8 to 4.0 times lower and the water angles 1.4–1.6 times smaller compared to the films synthesized from glucose (71.75 nm and 87.4°, respectively). Those films performed better as cell scaffolds: the number of viable NIH fibroblasts was 1.7–1.9 times higher than on polystyrene (control) or films of P(3HB) synthesized from glucose.

The influence of innovative hydrological developments on the chemical composition of muscle tissue of Clary catfish grown in a closed water supply system was studied. The use of feed and water with a modified molecular structure for growing Clary catfish had a positive effect on the development of fish muscle tissue.

The kinetics of the reaction between fluorine and benzene is studied experimentally at T = 293 K. Competitive reactions are used to find a reaction rate constant. The interaction is studied in a low-pressure flow reactor, and mass spectrometry is used to control the concentration of reagents and products. The reaction between fluorine atoms and methane is used as a competitive one. The ratio of rate constants of the studied reaction (k1) and a competitive one (k2) is found for the first time: k1/k2 = 4.4 ± 0.3. A rate constant is calculated for the reaction of fluorine atoms with benzene using literature data: k1 (293 K) = (2.7 ± 0.5) × 10‒10 cm3 molecule−1 s−1.