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The authors consider the possibility of using low-value pelagic fish species in the diet of people with restrictions on the consumption of nitrogenous extractive substances including nucleic acids which are sources of purine base metabolism. The objects of the study were chopped mackerel fillets from boiled fish and chopped boiled fillets from raw fish, quick-frozen minced horse mackerel of industrial processing in a boiled form. The studies were carried out in accordance with the experimental plan in which the duration of the heat treatment and the temperature of the cooking medium were the variable factors. The technology of combined fish masses with the addition of functional plant components has been proposed. It has been established that the dynamics of dry matter losses and heat losses of fish fillets is determined by the duration of cooking. In terms of organoleptic characteristics boiled minced meat from raw mackerel fillets is significantly inferior to the organoleptic characteristics of minced meat from pre-boiled fillets. When comparing the data for frozen and freshly prepared mince from horse mackerel, it has been found that the loss of nucleic acids in industrially prepared minced meat is 4.6-13.1 % higher ( T = 82 ± 2 and 98 ± 2 °C), the loss of nucleic acids by absolutely dry matter is higher by 11.3-5.8 %, mass - by 8.4-14.6 %. The content of the total amount of nucleic acids in industrial minced meat is 11.1 % lower than in freshly prepared minced meat. Obviously, in the process of preparing products for specialized purposes, including for preventive nutrition, it is preferable to use minced meat from boiled fish fillets.

Applying physical pressure in the uranyl–sulfate system has resulted in the formation of the first purely inorganic uranyl oxo-salt phase with a considerable uranyl bend: Na4[(UO2)(SO4)3]. In addition to a strong bend of the typically almost linear O═U═O, the typically equatorial plane is broken up by two out-of-plane oxygen positions. Computational investigations show the origin of the bending to lie in the applied physical pressure and not in the electronic influence or steric hindrance. The increase in pressure onto the system has been shown to increase uranyl bending. Furthermore, the phase formation is compared with a reference phase of a similar structure without uranyl bending, and a transition pressure of 2.5 GPa is predicted, which is well in agreement with the experimental results.

The tin–substituent bonds in Sn(II) organic compounds are studied by quantum chemical methods using the PC GAMESS-Firefly program package. The geometry optimization for the studied molecules is carried out by the DFT method (B3PW91functional, using the aug-cc-pVTZ-pp basis set with an effective core potential for tin and the 6-311++(2d,p) basis set for other atoms. The wave functions and the NBOs of tin–substituent bonds were calculated by the HF method using the x2c-TZVPall-electron relativistic basis set for the tin atom and the 6-311G(2d,p) basis set for other atoms. The values of topological characteristics of tin–substituent bonds are obtained by the AIM method. These bonds can be classified as “intermediate bonds” characterized by small contributions of Sn AOs in the MOs of the bonds, large differences between the charges on tin atoms, and low occupancies of the MOs of the bonds. The energies of Sn–R bonds are estimated.

To create the windings of the magnetic system of the Future Circular Collider, it is necessary to modernize the Nb3Sn-based composite superconductors obtained by the method of internal tin sources, which also involves an increase in the thermal conductivity and electrical conductivity of the matrix copper as determined using the residual resistance ratio (RRR) parameter (the ratio of the values of the electrical resistivity of copper at 273 and 20 K). The achievement of high RRR values is controlled by the balance between the geometric dimensions, the volume fractions of the superconductor components, and the mode of reaction heat treatment (RHT) used for the formation of the Nb3Sn phase. The results of an experimental and theoretical study of the effect of the strand diameter and the RHT mode on the RRR parameter are given. The diffusion of tin from the zone of subelements into the stabilizing copper in the course of RHT in strands of various diameters has been investigated by scanning electron microscopy and electron probe microanalysis. The study was carried out on experimental samples of multifilamentary superconductors based on Nb3Sn with a distributed Nb barrier.

Cast aluminium composite materials based on AD0 aluminium, reinforced with carbon nanotubes and aluminium oxide nanofibers are obtained. It is shown that the additives of 0.05 wt % of single wall carbon nanotubes (SWCNT) and aluminum oxide nanofibers (AONF) allow increasing ultimate tensile strength of cast metal by 15 % and 16 % respectively. Strengthening of the metal is maintained after cold deformation and annealing. Aluminum AD0 with additives SWCNT or AONF retains high strength after annealing, while aluminum without additives is significantly weakened, this allows to obtain annealed aluminum wire, with a strength limit of 54 – 69 % and yield strength of 53 – 78 % higher than that of metal without additives. The influence of SWCNT and AONF on the size of aluminum grain AD0 in the cast state, after cold deformation and annealing has been studied. Nano-additives have been found to inhibit the growth of metal grains at the stage of collective recrystallization, as well as to influence the process of primary recrystallization of aluminum.

When twisted into a cable, reduced, and wrapped, Nb3Sn composite superconductors are subject to significant deformation and can sustain damage that will affect their electrophysical properties. This article examines the effect of artificially induced surface damage on the electrophysical characteristics and microstructure of 0.82 and 0.7 mm in diameter Nb3Sn superconductors fabricated by the bronze technology and the internal tin source method. It is shown that the critical current of the deformed samples decreases with increasing depth, amount, and extent of the damage. The current-carrying capacity of a superconductor decreases with increasing deformation produced by flattening wire samples to thickness 0.6–0.4 mm.

To construct magnetic systems in modern high-energy physics projects, such as creation of the Future Circular Collider (FCC) and modernization of the Large Hadron Collider (HL-LHC), Nb3Sn superconductors with a high level of electrophysical properties, above all being a high current carrying capacity, are requisite. Such multifilament Nb3Sn superconductors are obtained by the technique of internal feeding of tin (IFT), consisting in deformation of a composite including high-purity niobium, copper, and tin to make a wire smaller less than 1 mm in diameter. The presence of such components as tin-based alloys or pure tin with Tm = 232°C in the composite wire composition precludes the possibility of Nb recrystallization annealing, which imposes strict requirements on the Nb mechanical properties, which determine the Nb capability for plastic deformation. In the study, the influence of the design and conditions of creating bimetal Nb/Cu rods on the grain structure of niobium and the state of the boundary between it and a copper sheath is discussed. The mechanical properties of rods at different steps of their fabrication are investigated. The results will be applied in development of the technological conditions of manufacture of Nb3Sn superconductors by the IFT technique.

The texture of niobium in composite Nb3Sn superconductors prepared by internal-tin-source and bronze techniques, and in a subelement, which is required for fabricating the composite using the internal-tin-source technique, is studied in this work. It is shown that prior to the reaction heat treatment, the structural components of Nb have the (110) drawing texture; after the reaction heat treatment, no preferred orientation of Nb3Sn superconducting compound grains is observed.

The problems associated with the corrosion of steel in sodium are examined. Equations including the physical constants characterizing mass transfer in the sodium–steel–impurity system are presented. The solution of the system of equations makes it possible to calculate the distribution of the dissolved components and suspensions in sodium flow. The source of the dispersed phase in the coolant fl ow is evaluated. A list of the constants used is presented. The presented constants must be refi ned in future work.

The structure and mechanical properties of composite Cu/Nb/Sn rods of various designs used in the fabrication of multifiber Nb3Sn superconductors prepared by the internal tin source method are studied. It is shown that, upon reaching a high degree of deformation (ln μ ~ 9), the tensile strength of the rods is ~700 MPa, while the plasticity drops to 2%. The structural features of the fracture surface of composite semifinished products are studied. The results will be used in the development of technological modes for the fabrication of Nb3Sn superconductors.

Bis-ADC complexes cis-[Pd{C(NHC6H4NH2)N(H)R}2]Cl2 (R = Xyl 4a, Cy 4b, C6H4-4-F 4c) and cis-[Pt{C(NHC6H4NH2)N(H)R}2]Cl2 (R = Xyl 5a, Cy 5b, C6H4-4-F 5c) were synthesized via the metal-mediated coupling of two isocyanide ligands in cis-[MCl2(CNR)2] (M = Pd, Pt; R = Xyl, Cy, C6H4-4-F) and 1,2-diaminobenzene. New compounds 4c and 5a–c were characterized by HR ESI+-MS, IR, and 1H, 13C{1H} and 195Pt{1H} NMR spectroscopy; the structures of 4a and 5a were elucidated by single-crystal X-ray diffraction. The stability of the ADC complexes in aqueous media (5 mM NaCl) was monitored by UV absorption spectroscopy, HR ESI+ mass spectrometry, and 195Pt{1H} NMR spectroscopy (for 5a). Molar conductivity measurements in MeOH (ΛM = 167–173 Ω−1 mol−1 cm2) indicate that, in this solvent, the ADC complexes exist as dicationic species of [A][Q]2 type. The ADC complexes binding to CT DNA was investigated by means of spectroscopic and hydrodynamic techniques including UV absorption and circular dichroism spectroscopy, fluorescence spectroscopy, low-gradient viscometry, flow birefringence, and AFM imaging. As a result, complexes 4a and 5a were shown to bind double-stranded DNA predominantly via the formation of monofunctional adducts in the major groove of the macromolecule. Binding of the ADC complexes also provokes the formation of a large number of intermolecular DNA–DNA contacts in solution. The antiproliferative activity of all prepared ADC complexes 4a–c and 5a–c was evaluated in vitro against three human carcinoma cell lines (HT-29, MDA-MB-231, and MCF-7) and two non-tumorigenic cell lines (L929 and RC-124) and compared to that of cisplatin. Among the compounds studied, complexes 4a and 5a appeared to be the most active species with IC50 values in MCF-7 cells of about 10 μM.

The mechanical properties of Ni-based superalloys are based on the hardening gamma-prime phase with an ordered structure. A solution for new phase precipitate growth is suggested for the case of the Ni-based alloys. In accordance with solution a mathematical model of gamma-prime phase precipitates growth during direct laser deposition, which is a type of DED-method, was developed in order to be able to predict the size of the hardening gamma-prime phase grains and thus the mechanical properties of the alloy. A series of experiments on depositing samples using Ni-based superalloys powder was carried out to verify this model.

Experimental studies of aluminium boride synthesis as a result of interaction of disperse aluminum with diborane B2H6 and disperse boron in a flow of thermal plasma of different composition generated in electric arc plasma torch have been carried out. Experimental work on the synthesis of aluminium boride nanoparticles from elements (a mixture of disperse aluminum and boron) has shown the possibility of obtaining in thermal plasma arc discharge of such phases of the boride as AlB12 and AlB31. The specific surface of the powders obtained is from 3 to 27 m2/g. According to X-ray phase analysis, the powders obtained, except for aluminum boride phases, also contain boron, aluminum, aluminum nitride and boric acid phases. The greatest yield of aluminum boride phases is provided by using the nitrogen plasma with hydrogen and enthalpy 4.5 kWt∙h/m3 in the reactor with increased high-temperature zone. The use of gaseous diborane made it possible to eliminate restrictions on the evaporation of boron particles but did not provide an opportunity to obtain aluminum borides in the plasma-chemical process. It was concluded that it is necessary to perform quenching of high-temperature gas flow containing boron and aluminum vapor to form aluminum borides from the gas phase in plasma-chemical synthesis. Such an approach should ensure that the temperature is reduced to the values at which aluminum borides are stable and that the formation of aluminum boride nanoparticles will occur as a result of condensation from the gas phase under these conditions.

Spatial and electronic structures of three-coordinated silicon molecules are calculated within MP2/6-311G(2d,p) and HF/6-311++G(3df,3pd) methods using the PC GAMESS-Firefly software package. AIM and NBO methods are used to determine main characteristics of silicon-substituent bonds in these molecules. Topologically, Si-C, Si-N, Si-Cl, and Si-O bonds may be characterized as “intermediate” bonds, and Si-Si bonds are characterized as covalent bonds.

A solution for new phase inclusion growth is suggested for the case of the Ni-based alloys. This solution takes into account a chemical composition of the alloy and conditions of the laser treatment process. A method for calculation of the chemical reaction rate constant is also suggested for the Ni3Al formation in the Ni-Al alloy. Modeling is fulfilled for the laser cladding process. Time dependences for the reacting component concentration is obtained as well as for intermetallic inclusion growth and thermal cycle.

Spheroidization of micropowders of a heat-resistant alloy based on nickel aluminide with a particle size of 20 to 45 μm was studied. The alloy was produced by calcium hydride reduction (CHR) and elemental synthesis (SHS). The spheroidization was carried out in a flow of argon–hydrogen thermal plasma generated by a direct-current (DC) plasma torch. The degree of spheroidization of the micropowders reached 98.5%, and the flowability was 20 s/50 g.

Spatial and electronic structures of six-coordinated germanium compounds are calculated within МР2 and AIM methods using PC GAMESS-Firefly, MORPHY, and AIMALL software packages. Main topological characteristics of germanium-substituent bonds are determined in these molecules.

Herein, we have synthesised a novel uranium oxyhydroxide (UOH) phase, Rb2K2[(UO2)6O4(OH)6]·(IO3)2, under hydrothermal conditions which intercalates IO3− via a hybrid salt-inclusion and host–guest mechanism. The mechanism is based on favorable intermolecular bonding between disordered Rb+/K+ and IO3− ions and hydroxyl and layer void positions respectively. To examine whether the intercalation may occur ubiquitously for UOH phases, the known UOH mineral phases metaschoepite ([(UO2)8O2(OH)12]·12H2O), compreignacite (K2[(UO2)6O4(OH)6]·7H2O) and also related β-UO2(OH)2 were synthesised and exposed to aqueous I− and IO3− for 1 month statically at RT and 60 °C in air and the solid analysed using laser ablation inductively coupled plasma mass spectroscopy. Measurements indicate intercalation can occur homogeneously, but the affinity is dependent upon the structure of the UOH phases and temperature, where higher temperatures and when the interlayer space is free of initial moieties are favoured. It was also found that after repeated washing of the UOH samples with DI water the intercalated iodine was retained. UOH phases are known to form during the oxidative corrosion of spent nuclear fuel during an accident scenario in the near field, this work suggests they may help retard the transport of radiolytic iodine into the environment during a long-term release event.

The paper presents the results of studying the peculiarities of heat and mass exchange in cold traps for the sodium purification of impurities in fast reactor circuits both in dedicated test areas simulating various trap components (isothermal sump, nonisothermal sump, filters, final cooling area) and in trap prototype models. As a result, a scientific rationale has been formed for developing traps of a unique design for various reactors. The impurity capacity of the traps is three to four times as high as that of the best foreign counterparts. Tests have shown these to be highly efficient in purifying sodium of oxygen and hydrogen and much less efficient in sodium purification of corrosion products and carbon. Taking into account the leakage of radioactive sodium during operation of the BN-600 reactor primary circuit traps, a decision was made to install the purification system in the reactor tank to improve the safety of the large fast reactor. It was resolved to exclude the accumulation of hydrogen in the primary circuit traps in nominal conditions. Two trap designs, with argon and sodium cooling, are discussed. It has been shown that operation of the reactor purification system with argon cooling will require 20 trap replacements during the reactor operating life and seven replacements if the deposition of hydrogen into the primary circuit cold traps is excluded. The sodium-cooled version of the trap built in the reactor tank has the same overall dimensions as the argon-cooled trap. The cooling sodium circulates in two trains: outside the jacketed working space body (up to 30% of the flow rate) and in the coil inside of the working space (up to 70% of the flow rate). Updates have been proposed to the trap design based on the calculations using the codes simulating the in-trap processes of heat and mass exchange.

A systematic investigation is presented which examines the structural chemistry of anhydrous and hydrous ternary hexavalent uranium and neptunium dinitrato, trinitrato, and tetranitrato complexes. Using slow evaporation methods under acidic conditions the uranium and neptunium nitrate complexes γ-K[UO

The effect of soil contamination with synthetic detergents (SD) Labomid-203, MS-8 and ML-51 in combination with potassium monoborate (MBP) on the change in the potential of soil erosion resistance (PER) was evaluated. PER characterizes the soil resistance to water erosion and is equal to the energy of a water jet acting perpendicular to the soil surface, required for the destruction and removal of a unit of soil mass from the area of its natural occurrence. Soil water retention curve (SWRC) and hydraulic conductivity were selected for the research as parameters determining soil erodibility. SWRC and moisture conductivity function are dependent on the surface tension and viscosity of the moisture in the soil, which are changed on soil contamination with surfactants of washing solutions. Integrating the expression for SWRC in the range of moisture content values from a fixed initial value to the value, corresponding to the complete filling of soil pores with moisture, gave the result correlating with the energy determining the potential for erosion resistance. Soil contamination with SD and MBP led to the significant decrease in soil erosion resistance, which is particularly evident at low moisture values. The largest decrease in soil erosion resistance (by an average of 39.6%) was caused by MS-8 (1.0% MS-8, 0.3% MBP). The smallest decrease in soil erosion resistance (by an average of 12.4%) was caused by ML-51 (0.5% ML-51, 0.1% MBP). The experiments were carried out with dark-gray and light-gray forest soils of the Chuvash Republic (Russia).

Fertigation practically always allows us to simultaneously solve a wide range of problems of supplying plants with mineral substances. It is due to the possibility to localize the application area in accordance with the structural features of the root system of the plant. A review of the studies on modeling and calculating the transfer of nutrients shows that spatial inhomogeneity of nutrients distribution may lead to their excess in wrong soil areas. Time intervals and volumes of applying dissolved fertilizers determine the not yet completely studied dynamics of concentration of the nutrition elements in the root area. Formation of the root system is under a strong influence of the boundaries of the wetting contour, since after the irrigation and soil drying nutrients tend to concentrate in this particular area. The results of transfer modeling showed significant differences in the final distribution of potassium monophosphate in soil depending on the initial distribution of moisture there. This can be pre-estimated and calculated. The designed software programme for modeling nutrients transfer with irrigation water allows the user to set various initial wetting gradients depending on the depth, the intervals between the drippers, the intensity and duration of watering. The calculations are made considering the basic hydrophysical soil characteristic and hydraulic conductivity function. The software is equipped with an interactive graphic interface for primary data processing, soil profile discretization and graphic representation of the results.

Three new sodium thorium arsenates, Na5Th4(AsO4)7 (1 ), Na5Th(AsO4)3 (2 ), and Na4Th(As2O7)2 (3 ) were synthesized via a high temperature route and their structures and optical properties were studied. Compound 1 adopts a three‐dimensional structure that consists of tetrameric fundamental building blocks (FBBs) [Th4(AsO4)7]5–, which are constructed by ThO8 and ThO9 polyhedra. The structures of 2 and 3 are based on open frameworks with channels running along the a or c axes, respectively, which are occupied by Na cations. Structural relations between the structures of 2 and 3 have been discussed regarding their composition. In contrast to the other two compounds, the arsenate anions in the structure of 2 play role of bridging ligands and do not connect more than two Th atoms. Owing to this, the underlying net of this compound contains only Th nodes has a lon topology. The Raman spectra of 1 and 2 contain similar peaks due to As–O vibrations of AsO4 groups, while the Raman spectrum of 3 differs significantly owing to the presence of As–O–As bridging group in As2O74– anions.

A systematic investigation of uranyl borates under different synthetic conditions resulted in five new 2D compounds, namely, (H3O)[(UO2)(BO3)], Li[(UO2)(BO3)]·(H2O), α‐K4[(UO2)5(BO3)2O4], β‐K4[(UO2)5(BO3)2O4] and K2.5[(UO2)5(BO3)2O2.5(OH)1.5]·(H2O)2.5. (H3O)[(UO2)(BO3)] and Li[(UO2)(BO3)]·(H2O) were obtained from hydrothermal reactions at 220 °C using the same mineralizer. Both materials possess the uranophane sheet topology with different symmetry of the unit cells. In the structure of (H3O)[(UO2)(BO3)] and Li[(UO2)(BO3)]·(H2O), UO7 pentagonal bipyramids share edges and vertexes with four BO3 planar triangles. α‐K4[(UO2)5(BO3)2O4] and β‐K4[(UO2)5(BO3)2O4] are polytypes. α‐K4[(UO2)5(BO3)2O4] was synthesized from a high‐temperature solid‐state reaction under ambient pressure; whereas β‐K4[(UO2)5(BO3)2O4] was obtained from a high‐temperature/high‐pressure (HT/HP) reaction. Both structures have an identical anion topology, but β‐K4[(UO2)5(BO3)2O4] crystallizes in space group with higher symmetry. In K2.5[(UO2)5(BO3)2O2.5(OH)1.5]·(H2O)2.5, which was obtained from a hydrothermal reaction, UO7 polyhedra share vertexes and edges with two independent BO3 triangles, forming the most complex uranyl borate layers among all five compounds. The different synthetic routes, novel topologies, thermal behavior and Raman spectra are discussed.

The influence of tungsten carbide and titanium nitride nanoparticles on the structure and properties of the weld metal of welded joints made by automatic twin submerged arc welding is considered. The nanoparticles have been introduced into the weld pool as a part of the “master alloy” based on nickel powder (PNE-1 according to GOST 9722). It has been shown that modifying the weld metal with tungsten carbide nanoparticles holds promise for enhancing the impact strength. In addition, it has been found that titanium nitride is prone to dissociation under the same conditions. However, microalloying with titanium, which is due to the release of titanium from the nitride, leads to an increase in the impact strength of the weld metal.

Two uranium and two thorium silicates were obtained using high temperature mixed fluxes methods. K14(UO2)3Si10O30 crystallizes in the P21/c space group and contains open-branched sechser (six) single silicate chains, whereas K2(UO2)Si2O6 crystallizes in the C2/c space group and is built of unbranched achter (eight) silicate chains. The crystals of K14(UO2)3Si10O30 and K2(UO2)Si2O6 are related by increasing U/Si molar ratios, and both structures contain the same secondary building units (SBUs), [USi6] heptamers. The triangle diagram for all known A+–UO22+–SiO44– phases demonstrates the high polymerization level of silicate groups in the system, which was compared with the family of A+–UO22+–BO33–/BO45– compounds. For both thorium silicates, the transformation of K2ThSi2O7 to K2ThSi3O9 was found to be a factor of the reaction time. K2ThSi2O7 crystallizes in the C2/c space group and belongs to the Na2SiVISi2O7 structure type. Its 3D framework consists of diorthosilicate Si2O7 group and ThO6 octahedra. Noncen...

Experimental studies on the synthesis of aluminum oxynitride nanopowders in a reactor with a confined plasma jet by the interaction of disperse aluminum with ammonia and oxygen in a flow of nitrogen plasma generated in an electric arc plasma torch are performed. Preliminary calculations of the equilibrium compositions and thermodynamic characteristics of the multicomponent Al–O–N system are carried out. An optimal design of the reaction prechamber of the reactor is performed. Powders having a cubic structure and consisting of aluminum oxynitride phases with an average particle size in the range from 20 to 200 nm are obtained. It is established that the specific surface area of the obtained powders increases from 20 to 71 m2/g, and the nitrogen content in the nanopowders increases from 3.6 to 14.7 wt % with an increase in the flow rate of quenching gas from 1.8 to 6.0 m3/h. At the same time, the oxygen content decreases from 35.5 to 25.5 wt %. At a minimal flow rate of the quenching gas, the metallic aluminum and its oxide phases are present in the obtained powders. With an increase in the amount of quenching gas, the conditions for the mixing of aluminum vapors with oxygen and atomic nitrogen from decomposing ammonia are improved, which leads to the formation of aluminum oxynitride and aluminum nitride. The variation of the synthesis parameters allows us to obtain aluminum oxynitride nanopowders having a specific surface area ranging from 28 to 50 m2/g containing from 1 to 11 wt % of nitrogen and from 25 to 40 wt % of oxygen.

Two series of palladium(II) and platinum(II) complexes featuring esters of tetrazol-1-yl and tetrazol-5-ylacetic acids {trans-[PdCl2L2] and trans-[PtCl2L2], L = 5-methyl-1H-tetrazol-1-ylacetic acid and its ethyl, butyl, isobutyl esters (1–5); 2-R-2H-tetrazol-5-ylacetic acid and its ethyl esters, R = tBu, CH2CH2OH (6–10)} were synthesized and their binding to calf-thymus DNA (CT DNA) and bovine serum albumin (BSA) were studied by means of experimental (CD, UV, viscometry, fluorometric and electrophoretic techniques) and theoretical methods. According to the spectrophotometric data, the interaction of the metal complexes with CT DNA is observed. The significant increase of melting point of CT DNA in the presence of the metal complexes (ΔTm = 8–13 °C) indicates strong stabilization of the DNA helix. Electrophoretic studies demonstrate the ability of the metal complexes to interact with pBR322 plasmid DNA and to change its mobility. According to the data of the fluorescence quenching technique, binding with constants (Kbin) of Pd(II) complexes with BSA are in the range 0.83–4.12 × 105 L M−1. The molecular docking studies show the minor groove binding behavior of tetrazole-containing palladium(II) and platinum(II) complexes to DNA (ΔGbinding. −5.56 − −6.12 kcal/mol) and effective binding to BSA via the favored binding site Trp213 (ΔGbinding −7.2 − −7.56 kcal/mol). The complex trans-[PtCl2(2-tert-butyl-tetrazol-5-ylacetic acid)2] exhibited noticeable antiproliferative activity in two human cancer cell lines with IC50 values of 11.40 µM in HT-29 cells and 11.02 µM in MDA-MB-231 cell line.

Composite materials on the basis of A5 aluminum containing 0.01–0.1 wt % of carbon nanotubes (CNT) were obtained. The composite materials were fabricated by sand casting. Carbon nanotubes were added to the aluminum melt in the form of powdered mixture preliminarily produced using an AGO2S planetary ball mill. It was demonstrated that the CNT additions improved the ultimate tensile strength and yield strength of cast metal by 9 and 32%, respectively. The improvement of metal strength properties even at such a minor amount of nanotubes is determined not only by the inoculating effect but also by dispersion, dislocation, and, to a lesser extent, by reinforcing mechanisms of strengthening. For CNT content in aluminum equal to 0.01 wt %, the calculated yield strength agrees well with experimental values, whereas for CNT content equal to 0.05 and 0.1 wt %, the obtained strengthening is significantly lower than calculations, which can be attributed to agglomeration of nanotubes. The degree of conversion of carbon nanotubes into aluminum carbide as a consequence of interaction with aluminum melt is analyzed. It is demonstrated that less than 50% of carbon nanotubes are transformed into aluminum carbide during melting at 700–800°C. The fact that CNTs are not completely converted into carbide can be attributed to the fact that CNTs are arranged into bundles and only top layer of CNTs is in contact with the melt.

A study of neptunium (Np) chemistry in the complex oxo-selenium system has been performed. Hereby, two sets of precipitation experiments were conducted, investigating the influence of the initial oxidation state of selenium using SeIVO2 and H2SeVIO4 with NpV in alkali nitrate solution, keeping the ratio of Np/Se constant. Surprising results were observed. Five novel neptunium and selenium bearing compounds have been obtained by slow evaporation from aqueous solution. The novel NpIV phase K4-x[Np(SeO3)4-x(HSeO3)x]·(H2O)1.5 (1) crystallizes in green-colored, plate-shaped crystals and was obtained by adding SeO2 and ANO3 to a NpV stock solution. Single-crystal X-ray diffraction reveals one-dimensional chain structures composed of square antiprismatic NpO8 polyhedra linked via four trigonal pyramidal SeO3 and HSeO3 units. Raman spectral analysis supports the presence of both selenite and hydroselenite due to the presence of corresponding modes within the spectra. The addition of selenic acid to a NpV stock so...

The Olenek Artesian Basin contains in its subsurface huge reserves of hydromineral resources with extremely high concentrations of many useful components. The presented estimates of prospective reserves of brines drained by a large diamond-mining quarry proves the extremely high potential of the use of “liquid ore” as an alternative to solid mineral deposits.

The effect of processing multicomponent nanopowders of the W-C system obtained by plasma-chemical synthesis in a microwave electromagnetic field with a frequency of 24 GHz, generated by continuous gyrotron, has been experimentally studied. It was found that the formation of nanosized particles of tungsten carbide WC occurs during microwave treatment. The influence of the processing time, microwave power and the composition of the gas atmosphere on the phase composition of nanopowders, their morphology and specific surface area was investigated. It has been found that processing in a microwave field can reduce the time of chemical transformations, leading to the formation of tungsten monocarbide, by an order of magnitude compared to traditional heating in an electric furnace in a hydrogen environment. At the same time, the particle size is preserved in the nanometer range.

Results of investigation of the parameters of the THL-100 hybrid laser system of visible range developed at the IHCE SB RAS in collaboration with the LPI RAS are presented. The laser system consists of the Ti:Sa Start-480M starting complex and the photodissociation XeF(C-A) amplifier with aperture of 24 cm. The starting complex provides 50-fs spectrally limited radiation pulses with energy of the second harmonic (475 nm) up to 20 mJ and 50-ps positively chirped radiation pulses with energy up to 5 mJ. The active medium of the XeF(CA) amplifier is created in the XeF2/N2 mixture upon exposure to VUV radiation of xenon excited by a highpower electron beam. It is demonstrated that record power of 14 TW is attained by amplification of negatively chirped radiation pulse with duration of 1.6 ps in the XeF(C-A) amplifier, and maximum energy of ~3.2 J is realized by amplification of positively chirped radiation pulse.

A series of novel uranyl borates, K4Sr4[(UO2)13(B2O5)2(BO3)2O12], A6[(UO2)12(BO3)8O3](H2O)6 (A = Rb and Cs), and Rb3[(UO2)3(BO3)2O(OH)](H2O), were synthesized using conventional conditions. Among them, K4Sr4[(UO2)13(B2O5)2(BO3)2O12] and A6[(UO2)12(BO3)8O3](H2O)6 were obtained through a high-temperature solid-state reaction method, whereas Rb3[(UO2)3(BO3)2O(OH)](H2O) was synthesized via a hydrothermal reaction. All compounds adopt novel two-dimensional (2D) layered structures in which basic building units (BBUs) consist of corner- or edge-sharing UOx (x = 6, 7 and 8) polyhedra linked with planar BO3 triangles or B2O5 dimers. K4Sr4[(UO2)13(B2O5)2(BO3)2O12] is the first mixed alkali–alkaline earth metal uranyl borate. This compound has the most complex 2D anion topology observed thus far in 2D uranyl borates. The fundamental building block (FBB) in this structure, [(UO2)13(B2O5)2(BO3)2O12]12–, consists of 3 UO8 hexagonal bipyramids and 10 UO7 pentagonal bipyramids connected with 2 BO3 triangles and 2 B2O5 di...

It is shown that powders of a model high alloy consisting of spherical particles 25–50 μm in size can be synthesized from a starting ultradispersed powder, which is made of a mixture of the alloy components and is fabricated by the magnesiothermal reduction of metal chlorides in the potassium chloride melt. The synthesis includes the stages of microgranulation of an ultradispersed powder, heat treatment of microgranules, classification of the microgranules with the separation of microgranule fraction of 25–50 μm, spheroidization of the separated fraction in a thermal plasma flow, and classification with the separation of a fraction of micro- and submicrometer-sized particles.

This article discusses the possibility of introducing nanosized particles into a molten pool using a flux-cored wire. A flux-cored wire has been proposed with added composite granules obtained upon the combined treatment of nickel powder and nanosized particles. In order to avoid the overheating of particles, it has been proposed to add a flux-cored wire to a molten-pool tail using preheating. The following hardmelting particles have been tested: tungsten carbide (WC), titanium nitride (TiN), and aluminum oxide (Al2O3). It has been demonstrated that the addition of tungsten carbide to a molten pool improves the stability of weld-metal (WM) impact toughness while retaining its average value and the addition of aluminum oxide to a molten pool leads to increased average values of WM impact toughness while retaining its stability. Meanwhile, nanosized particles of titanium nitride in a molten pool are prone to dissociation, which leads to the formation of porosity, thus limiting the field of application of this modifier.

The possibility of increasing the sensitivity of a neutron detector based on a TlInSe2 crystal by introducing the 6Li isotope into this crystal is investigated. Introduction of the isotope is conducted by the method of electrochemical intercalation from aqueous and nonaqueous solutions of LiCl and also from the melt of the LiCl–KCl eutectic. It is shown that intercalation by the electrochemical method from a LiCl solution in propylene carbonate, performed along the “c” axis of the crystal (along strong bond chains) is efficient. The attained concentration of introduced lithium amounts to (1–1.2) × 1021 cm–3, which increased the sensitivity of the detector by approximately four times. Good agreement between the calculated and experimental values of the detector sensitivity is demonstrated.

Experimental data on the precipitation of an impurity (sodium oxide) in sodium coolant in a model of a cold trap of a fast reactor are obtained using a specially developed technique. The working model included the zones of filtration, spontaneous cooling, and cooled settling tank, which were intended for collecting the settling impurities. The working cavity was cooled by sodium-potassium alloy melt outside its housing. It is shown that there are two local maxima in the distribution of the sodium oxide deposits along the height of the model; these peaks correspond to the initial and final sections of the cooling zone. The model constants of impurity mass transfer in the model of a cold trap are refined experimentally. The calculations performed with the refined model of mass transfer for the standard variant of a cold trap built into the reactor tank showed that the model constants are optimal.

The method of production of group IV powders for additive manufacturing is presented. Powders are produced in the hydrogenation-dehydrogenation process followed by plasma spheroidization of prepared polygonal powders. The dependence of composition of hydrides on amount of absorbed hydrogen is established for the group IV metals; it allows optimizing the technological parameters of processes for hydrogenation and grinding. It is shown that spherical powders of titanium, Ti–6Al–4V, and Zr–10% Ti of mass fractions of 40–70 μm and not less than 40 μm with calculated spheroidization level achieving 96% may be produced in Ar + 8 vol % H2 thermal plasma flow generated by an arc-jet plasma generator. The average roundness factor is 1.01.

One of the probable mechanisms that controls the composition of highly mineralized chloride groundwaters is studied using physicochemical numerical simulations of equilibria in water–rock systems. Concentrated brines in the Olenek cryoartesian basin in the northeastern Siberian Platform are determined to be undersaturated with respect of major rock-forming minerals, which suggests that the metamorphosed sedimentary brines should have been diluted by meteoric waters during a certain evolutionary episode of the permafrost zone of the basin in the Late Pleistocene and Holocene.

Malignant tumors are the second most frequent cause of death after cardiovascular diseases. The photodynamic therapy based on the interaction of laser light with different photosensitizers was discovered in the 20th century as one of treatment methods. When using photosensitizers, the process of singlet oxygen and other active forms generation is observed in both malignant and healthy body tissues, which leads to a number of adverse reactions. More promising diagnostic compounds that do not have these disadvantages are ytterbium porphyrin complexes. These compounds slightly generate singlet oxygen under light irradiation, while maintaining a high level of tumorotropic agents as for therapeutic photosensitizers. This work continues a series of studies devoted to the analysis of physicochemical properties of Yb-complex 2,4-dimetoxyhematoporphyrin IX as a promising marker for fluorescent diagnostics of various tumors. Pharmaceutical compositions based on Yb3+-dimetoxyhematoporphyrin IX dipotassium salt were created. These compositions are capable of accumulating in the sites of inflammation and proliferation in diseases of mucosal membranes and cancer lesions. Toxicological and pharmacokinetic studies were carried out with the use of laboratory animals and volunteers. The analysis results showed that the pharmaceutical compositions are perspective for use in clinical practice.

In creating a large-scale atomic-hydrogen power industry, the resolution of technological issues associated with high temperatures in reactor plants (900 °C) and large hydrogen concentrations intended as long-term resources takes on particular importance. The paper considers technological aspects of removing impurities from high-temperature sodium used as a coolant in the high-temperature fast reactor (BN-HT) 600 MW (th.) intended for the production of hydrogen as well as other innovative applications. The authors examine the behavior of impurities in the BN-HT circuits associated with the mass transfer intensification at high temperatures (Arrhenius law) in different operating modes. Special attention is given to sodium purification from hydrogen, tritium and corrosion products in the BN-HT. Sodium purification from hydrogen and tritium by their evacuation through vanadium or niobium membranes will make it possible to develop compact highly-efficient sodium purification systems. It has been shown that sodium purification from tritium to concentrations providing the maximum permissible concentration of the produced hydrogen (3.6 Bq/l according to NRB-99/2009) specifies more stringent requirements to the hydrogen removal system, i.e., the permeability index of the secondary tritium removal system should exceed 140 kg/s. Provided that a BN-HN-type reactor meets these conditions, the bulk of tritium (98%) will be accumulated in the compact sodium purification system of the secondary circuit, 0.6% (∼ 4·104 Bq/s), will be released into the environment and 1.3% will enter the product (hydrogen). The intensity of corrosion products (CPs) coming into sodium is determined by the corrosion rate of structural materials: at a high temperature level, a significant amount of corrosion products flows into sodium. The performed calculations showed that, for the primary BN-HT circuit, the amount of corrosion products formed at the oxygen concentration in sodium of 1 mln–1 exceeds 900 kg/yr with fuel element claddings made of EP-912-VD steel and 464 kg/yr with molybdenum alloy claddings. For the secondary circuit, the amount of corrosion products totals 263 kg/yr for each loop. Taking into account the high-temperature experiments which demonstrated high efficiency of retaining corrosion product suspensions by the strainers located in the low-temperature area, it is proposed to cool sodium to the required temperature alongside the corrosion products retention on the mass transfer surfaces, including strainers. It is shown that, by using 30% of the power required to produce hydrogen with 50% efficiency, the BN-HT is capable of producing about 0.6·106m3 of hydrogen per 24 hours which is sufficient for modern large-scale enterprises processing medium-grade crude oil or the implementation of other technologies.

Through the use of a high-temperature/high-pressure synthesis method, four thorium oxo-tellurium compounds with different tellurium valence states were isolated. The novel inorganic phases illustrate the intrinsic complexity of the actinide tellurium chemistry under extreme conditions of pressure and temperature. Th2Te3O11 is the first instance of a mixed-valent oxo-tellurium compound, and at the same time, Te exhibits three different coordination environments (TeIVO3, TeIVO4, and TeVIO6) within a single structure. These three types of Te polyhedra are further fused together, resulting in a [Te3O11]8– fragment. Na4Th2(TeVI3O15) and K2Th(TeVIO4)3 are the first alkaline thorium tellurates described in the literature. Both compounds are constructed from ThO9 tricapped trigonal prisms and TeVIO6 octahedra. Na4Th2(TeVI3O15) is a three-dimensional framework based on Th2O15 and Te2O10 dimers, while K2Th(TeVIO4)3 contains tungsten oxide bronze like Te layers linked by ThO9 polyhedra. The structure of β-Th(TeIVO3)...

A new alkali thorium phosphate family, A2Th(PO4)2 (A = Li, Na, K, Rb, Cs), has been synthesized and systematically investigated. The structural evolution of this new family was compared with that of the previously reported arsenic-based family A2Th(AsO4)2 (A = Li, Na, K, Rb, Cs). Similar compositions of the phosphorus- and arsenic-containing series allowed their direct comparison in order to reveal the influence of the size and nature of either monovalent or pnictogen cations on the crystal structure and related properties. Detailed crystal chemical analyses suggest that two main driving forces are in charge for the structural evolution, i.e., the size of alkali cations as well as the local environment of the thorium polyhedra and the TO4 (T = P, As) tetrahedra. Raman spectra were measured for all studied phases and bands have been assigned. The density functional theory calculations revealed that the local environment of the PO4 tetrahedra may be responsible for shifts of PO4 vibrational bands observed i...

Synthesis, structural and spectroscopic characterization, and topological analysis of five novel uranyl-based silicates and germanates have been performed. The open-framework K4(UO2)2Si8O20·4H2O has been synthesized under hydrothermal conditions and is based upon [USi6] heptamers interconnected via edge-sharing. Its structure is composed of sechser silicate layers with 4-, 8-, and 16-membered rings. The largest 16-membered rings have an average dimension of ∼8.93 × 9.42 A2. β-K2(UO2)Si4O10 has been obtained by the high-temperature flux growth method. Its 3D framework contains a loop-branched sechser single layer with 4- and 8-membered rings and consists of the same [USi6] heptamers as observed in K4(UO2)2Si8O20·4H2O. Na6(UO2)3(Si2O7)2 has also been synthesized from melted fluxes and represents a 2D layer structure composed by [USi4] pentamers. Two iso-structural compounds A+(UO2)(HGeO4)·H2O (A+ = Rb+, Cs+) were synthesized via the hydrothermal method, and their structures are of the α-uranophane type. The 2D layers consist of [U2Ge2] tetramer secondary building units (SBUs). The Raman spectra of all novel phases were collected, and bands were assigned according to the existing oxo-silicate rings and oxo-germanium units. Additionally, we performed a statistical investigation of the local coordination of uranyl ions in all known inorganic structures with different oxo-anions (TOx, T = B3+, Si/Ge4+, P/As5+, S/Se/Te6+, Cr/Mo/W6+, P/As3+, and Se/Te4+). We found a direct correlation between the ionic potential of the central cations T in oxo-anions in their higher oxidation states and the coordination number of uranyl groups.

The synthesis of titanium nitride and carbonitride nanopowders from titanium tetrachloride vapor in a stream of hydrogen–nitrogen plasma, generated by an arc torch, in confined-jet flow reactor has been experimentally studied. Single-phase nanopowders with a NaCl-type cubic crystal lattice as assemblies of preferably cube-shaped nanoparticles of a 20–150 nm size and aggregates based on them have been obtained in the experiments. By varying the synthesis parameters, it has been possible to prepare titanium nitride nanopowders with a specific surface area in the range of 11–39 m2/g containing 18.8–22.5 wt % nitrogen, which corresponds to the empirical formula TiN0.79–TiN0.99. The titanium carbonitride nanopowders had a specific surface area of 13–23 m2/g and carbon and nitrogen contents of 7.5–13.6 and 13.5–5.1 wt %, respectively.

Four novel alkaline earth metal uranyl borates, namely, A[(UO2)5(BO3)2O2(OH)2]·5H2O (SrUBO-1, BaUBO-1) and A[(UO2)2(B2O5)O] (SrUBO-2, BaUBO-2) (A = Sr, Ba), have been prepared; SrUBO-1, BaUBO-1, and BaUBO-2 were synthesized using hydrothermal methods, whereas SrUBO-2 was prepared by a traditional high-temperature solid-state method. The compounds SrUBO-1 and BaUBO-1 were found to be iso-structural and crystallized in the centrosymmetric group C2/c. Their structure features two-dimensional anionic layers {[(UO2)5(BO3)2O2(OH)2]2–}n that are composed of [(UO2)5O2(OH)2]4+ clusters and [BO3]3– polyanions. From a topological point of view, this two-dimensional anionic layer can be described as a new 4-nodal net topological type with a point symbol of {35.45}2{36.46.53}3{37.47.57}2. SrUBO-2 and BaUBO-2 are iso-structural and crystallized in space group C2/m. Their structures are based on a three-dimensional framework {[(UO2)2(B2O5)O]2–}n. Within the three-dimensional framework, two-dimensional U(2)–U(1) = U(3) l...

Equilibrium energy and technological characteristics of the plasma synthesis of titanium nitride, carbide, and carbonitride, in particular, the composition and yields of final products, energy consumption upon their production, and the required enthalpy of a plasma flow, are calculated for the following reactions: TiCl4 + xH2 + yN2 (synthesis of TiN), TiCl4 + xH2 + zCmHn (synthesis of TiC), and TiCl4 + xH2 + y1N2 + z1CmHn (synthesis of TiCN). The calculations are carried out for the temperature range from 500 to 4000 K, at the total pressure of 0.1 MPa in the system, and with the following molar ratios of reagents: x = 8, x = 20; y = 0.5, y = 5, y = 20; z = 0.9, z = 1.0, z = 1.1; y1 = 5; z1 = 0.4, z1 = 0.5, z1 = 0.6.

In our research, the method of manufacturing an Al-carbon nanotube (CNT) composite by hot pressing and cold rolling was attempted. The addition of one percent of multi-walled carbon nanotubes synthesized by OCSiAl provides a significant increase in the ultimate tensile strength of aluminum. The tensile strength of the obtained composite material is at the tensile strength level of medium-strength aluminum alloys.