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Extraframework cations define the chemical versatility of zeolite catalysts. Addressing their structural complexity and dynamic behavior represents one of the main fundamental challenges in the field. Herein, we present a computational approach for the identification and analysis of the accessible pool of intrazeolite extraframework complexes with a Cu/MOR catalyst as an industrially important model system. We employ ab initio molecular dynamics for capturing the ensemble of reactive isomers with the [Cu3O3]2+ stoichiometry confined in the mordenite channels. The high structural diversity of the generated isomers was ensured by concentrating the kinetic energy along the low-curvature directions of the potential energy surface (PES). Geometrically distinct [Cu3O3]2+ complexes were identified via a series of clustering procedures ensuring that one structure of each local minima is retained. The proposed procedure has resulted in a set of previously unknown peroxo-complexes, which are >50 kJ/mol more stable than the recently hypothesized chair-shaped structure. Our analysis demonstrates that the most stable peroxo-containing clusters can be formed under operando conditions from molecular oxygen and the Cu3O unit, similar to that in methane monooxygenase (MMO) enzymes.

Mixed ionic-electronic conductors (MIECs) based on YFeO3 are positioned as one of the promising cathode materials for intermediate-temperature solid oxide fuel cells (so-called protonic ceramic fuel cells or PCFCs) based on proton-conducting electrolytes. Simultaneous modification of both basic cationic sublattices of YFeO3 by calcium and iron was used to tailor the functionality of the obtained Y0.9Ca0.1Fe1–хСoхO3–δ (x = 0.2, 0.3, 0.4 and 0.5) compounds. Following the successful synthesis of these oxides, such functional characteristics as structural, thermal, transport properties and electrochemical activity were extensively studied taking the composition (i.e. cobalt concentration, x) into account. The complex analysis carried out on the obtained data shows that Co-doping results in improved electrical conductivity and electrochemical polarisation resistance with no adverse effects on their thermal expansion, even at the highest cobalt content (x = 0.5). The performance of a single SOFC with the selected Y0.9Ca0.1Fe0.5Сo0.5O3–δ electrode confirms the prospects of Y0.9Ca0.1Fe1–хСoхO3–δ phases as modernized MIECs having good thermal properties and acceptable electrochemical activity.

Charrs of the genus Salvelinus form distinct trophic morphs living in sympatry in numerous postglacial lakes. Here we demonstrate that charrs can diversify into amphipod foraging specialists and sedentary macrobenthos consumers in the shallow-water ecosystems. This pattern was revealed in three out of six lakes under exploration supported by differences in stomach content, trophic-transmitted parasite, and stable isotope ratio analyzes. The body shape and growth rate comparison indicates that this kind of trophic-based diversification emerges at a juvenile stage and is maintained throughout the whole life. The restriction in gene flow found between the morphs allows to propose the possibility for the hereditable-based specialization to evolve. We found that those diversification phenomena are possible only in the lakes situated in vicinity of the ocean coastline, while no evidence of this split was found for inland mountain lakes. We suggest that the trophic-based diversification in the littoral ecosystems is accounted for the heterogeneity in the ecological conditions and food resources’ distribution linked to coastal wind action. This phenomenon was previously reported for the charr in Lake Fjellfrosvatn, Scandinavia, so it seems to be some universal yet poorly described kind of disruptive selection pressure for northern latitude fishes.

The specific activity of 235U and content of native uranium for the Kharkiv region in drinking water, soil, roots, the leaf of hydrophyte “Pistia stratiotes” and the samples of kidney stones obtained from patients with urolithiasis were measuring by using gamma activation analysis on linac accelerator of NSC KIPT. The whole sample contained alpha-emitter uranium.

The photonuclear technology of preparation radioactive cisplatin 195mPt was been developed by the bremsstrahlung from the electron accelerators. In the novel technology, the production of 195mPt from reaction 197Au(γ,np)195mPt with a high specific activity >1 Ci/mg-1 was realized. The Ehrlich adenocarcinoma cells were been used as a neoplastic model. There are two groups: 1. tumor cells with non-radioactive cisplatin; 2. tumor cells with radioactive cisplatin (0.17 pg 195mPt-cisplatin). The number of morphology death cells as a result of radioactive cisplatin action was more than after action of non-radioactive cisplatin. The different mechanisms of the morphology death cell (necrosis for non-radioactive and apoptosis for radioactive) were detected.

The paper presents the results of the transmission electron microscopy of the evolution of the dislocation substructure (DSS) of the polycrystalline ordered and disordered Pd3Fe alloys with low-stable structure and phase compositions. A flow chart is suggested for the transformation of the dislocation substructures during a transition from one stage to another. These stages are indicated on the stress-strain curves of the Pd3Fe alloy. It is found that in the case of both disordered and ordered alloys, each deformation stage is characterized by a specific dislocation substructure, which is the main deformation medium for each stage. A transition from one DSS type to another occurs at a certain range of the deformation degree. The DSS type characteristic to a given stage of deformation appears at a preceded stage and its amount increases with the deformation growth. At a given deformation stage, this amount is the highest, while during the transition to another stage, it gradually lowers and disappears. In the ordered alloys, the DSS types differ from those in the disordered alloys at the same deformation stage. It is shown that at each deformation stage, there are specific dislocation substructures or deformation media. During the transition to a new stage, the transition to a new structural deformation media occurs, and these media exist together. This is characteristic to the low-stability state of the whole system.

Orientation of water molecules in the vicinity of the globular protein SNase is studied. It is shown that two types of characteristic orientations can be distinguished among molecules in direct contact with the protein. Approximately 44% of these molecules are oriented by their OH vector towards the nearest protein atom forming a donor hydrogen bond; 20% of them are directed by their oxygen towards the nearest atom while their protons are directed mainly away from the protein. By forming a network of hydrogen bonds with other water molecules, these molecules initiate orientation correlations in the protein environment within a region of 0.45 nm. More distant water molecules are arranged randomly with respect to the protein. The orientation is described by the angle between vector N directed from the water molecule to the nearest protein atom and characteristic vectors of the water molecule (directions OH, OL, and dipole moment D). A more detailed information about orientations is retrieved from a two-dimensional distribution diagram P(cos(θ), φ) representing direction N in a spherical coordinate system associated with the water molecule. The diagram provides an unambiguous description for the orientation of water molecules and allows a quantitative calculation of the fraction of molecules with a specified orientation.

The interface between LibXC and GAMESS (US), which enables the latter to perform calculations with >200 popular density functional approximations, including recently proposed r2SCAN, M06-SX and CAM-QTP00, is presented. The LibXC-GAMESS interface allows users to specify custom functionals as linear combinations of the present ones, exact exchange (producing hybrids) and MP2-correlation (producing double-hybrids).

One of the key directions for the development of commercial solid oxide fuel cells fuelled by natural gases consists in the search for efficient fuel electrode materials operated under hydrocarbon-containing atmospheres. Within the present work, we synthesized and characterised novel composites based on a double-perovskite Sr2Ni0.75Mg0.25MoO6–δ phase and a second phase comprised of SrMoO4 or NiO. For these composite materials, the reduction behaviour, tolerance to carbon dioxide and catalytic activity towards the partial oxidation of hydrocarbons mixture were comprehensively studied. It is shown that the target properties of the designed composites are affected not only by the type of catalysts but also by the method of their preparation. According to the presented results, the most appropriate materials are composites containing 20 wt% SrMoO4 or 50 wt% NiO.

Flat circular discs in powered operation mode create driving forces. These forces enable to decrease the wheel slippage of the energy saturated tractor of tillage unit and to reduce the specific energy consumption. The objective of this study was to develop a technique that enables to determine the driving disc optimal parameters for maximum efficiency criterion. The earlier developed mathematical model of soil-disc interaction was used for this purpose. Soil properties in the model are characterized by means of two empirical constants. The relative depth and the kinematic parameter determine the disc operation mode. It was shown that the driving disc can operate with high efficiency, if the disc operates at the optimal values of the parameters. The driving disc efficiency can achieve the value about fifty percent. The experimental results confirmed the adequacy of the technique. The discrepancy between the predicted and field experimental values of driving forces and applied moments was about 25%. The proposed technique can be modified to optimize the parameters of other powered rotary tools of tillage machines and units.

Ethylene and 1-hexene were copolymerized by a hafnium salan-type catalyst activated by B(C₆F₅)₃ producing copolymers over a wide range of 1-hexene incorporation. GPC analysis of the resulting copolymers showed a low dispersity index, suggesting that the catalyst behaves as a single-site catalyst. Deuterium labeling experiments revealed that primary active sites decreased as secondary sites increased throughout the reaction. Deactivation of the Hf catalyst during copolymerization was observed; however, the deactivation was suppressed at a higher concentration of 1-hexene. Analysis of multiresponse kinetic data including 1-hexene consumption, active-site quantification, end-group analysis, and triad composition analysis led to determination of the polymerization mechanism and the associated rate constants. Major features of the kinetic model of this catalyst system are (1) the rate constants for ethylene insertion are faster than for 1-hexene insertion by a factor of 2; however, (2) the rate constants are significantly affected by the last monomer inserted. The rate constants for inserting into an ethylene group are slower than for inserting into 1-hexene group by a factor of 10. The data support a mechanism where catalyst sites that misinsert 1-hexene following an ethylene insertion become inactive.

Stable bridged azaozonides can be selectively assembled via a catalyst-free three-component condensation of 1,5-diketones, hydrogen peroxide, and an NH-group source such as aqueous ammonia or ammonium salts. This procedure is scalable and can produce gram quantities of bicyclic stereochemically rich heterocycles. The new azaozonides are thermally stable and can be stored at room temperature for several months without decomposition and for at least 1 year at -10 °C. The chemical stability of azaozonides was explored for their subsequent selective transformations including the first example of an aminoperoxide rearrangement that preserves the peroxide group. The amino group in aminoperoxides has remarkably low nucleophilicity and does not participate in the usual amine alkylation and acylation reactions. These observations and the 15 pKa units decrease in basicity in comparison with a typical dialkyl amine are attributed to the strong hyperconjugative nN→σ*C-O interaction with the two antiperiplanar C-O bonds. Due to the weakness of the complementary nO→σ*C-N donation from the peroxide oxygens (a consequence of "inverse α-effect"), this interaction depletes electron density from the NH moiety, protects it from oxidation, and makes it similar in properties to an amide.

Two metal-organic frameworks (MOFs), UiO-66 and UiO-66-NH2, were considered as containers for bioactive chemicals. We provide a synthesis technique, which allowed the production of these materials suitable for biomedical applications. Both MOFs were characterized as single-phase porous materials composed of nanoparticles (30-65 nm) with a ζ-potential of more than 40 mV in water suspension. D,L-Leucine was applied as a model molecule, which allowed us to trace the mechanism of the loading process. We showed that after synthesis, amino groups of UiO-66-NH2 are coordinated with solvent residuals. It results in a similar route of leucine loading in UiO-66 and UiO-66-NH2 samples. Using joint data of thermogravimetric analysis and calorimetry, infrared spectroscopy, and nitrogen adsorption, we revealed that methyl groups of leucine molecules are responsible for bonding of an MOF matrix. We proposed the formation of bonds between CH3 groups and benzene rings of linkers via CH-π interaction. We also assessed the toxicity of the synthesized MOFs toward HeLa cells at 50 μg/mL after 24 h incubation and revealed no negative effects on the viability of the cells, prompting further biomedical research in the areas of small-molecule delivery and cell signaling and metabolism modulation.

Acetylene is an effective additive to various rocket fuels. Acetam, an equilibrium highly concentrated solution of acetylene in liquid ammonia, is a promising fuel for use in liquid−propellant jet engines. To gain insights into the processes occurring in such systems and provide means for predicting their characteristics, the self-ignition of model acetylene−oxygen−argon mixtures is experimentally and theoretically studied. The experiments are performed behind reflected shock waves in a temperature range from 1100 to 1870 K at a total gas concentration of [M] ≈ 1.0 × 10−5 mol/cm3, with chemiluminescence signals from electronically excited C2* (λ ≅ 516 nm), CH* (429 nm), CO2*(363 nm), and OH* (308 nm) recorded. Numerical simulations within the framework of various detailed kinetic mechanisms closely reproduce the measured temperature dependences of the ignition delay time for the tested mixtures, but in some cases fail to satisfactorily describe the time profiles of the emission signals from C2*, CH*, CO2*, and OH*. The performed numerical simulations make it possible to explain the observed characteristic features of the emission profiles of electronically excited C2*, CH*, CO2*, and OH* during the self-ignition of C2H2–O2−Ar mixtures. Sensitivity analysis demonstrates that the existence and characteristics of the preignition stage in the CO2* and OH* emission signals are largely determined by the kinetic behavior of intermediate species, such as the ketene molecule and CH2 radical. Based on the results obtained, a new detailed kinetic mechanism has been proposed for describing processes in the combustion products of acetylene-containing propellants, in particular chemiluminescent glow, which are of considerable interest for the development of new technologies for astronautics and aeronautics.

The analysis of biological sequencing data has been one of the biggest applications of string algorithms. The approaches used in many such applications are based on the analysis of k -mers, which are short fixed-length strings present in a dataset. While these approaches are rather diverse, storing and querying a k -mer set has emerged as a shared underlying component. A set of k -mers has unique features and applications that, over the past 10 years, have resulted in many specialized approaches for its representation. In this survey, we give a unified presentation and comparison of the data structures that have been proposed to store and query a k -mer set. We hope this survey will serve as a resource for researchers in the field as well as make the area more accessible to researchers outside the field.

A new Finite Difference complete in phase method with vanished derivatives of the Phase-lag up to order five for the initial value problems with periodical and/or oscillating solutions is produced in the present paper.

Spatially encoded measurements of transient optical transmissivity became a standard tool for temporal diagnostics of free-electron-laser (FEL) pulses, as well as for the arrival time measurements in X-ray pump and optical probe experiments. The modern experimental techniques can measure changes in optical coefficients with a temporal resolution better than 10 fs. This, in an ideal case, would imply a similar resolution for the temporal pulse properties and the arrival time jitter between the FEL and optical laser pulses. However, carrier transport within the material and out of its surface, as well as carrier recombination may, in addition, significantly decrease the number of carriers. This would strongly affect the transient optical properties, making the diagnostic measurement inaccurate. Below we analyze in detail the effects of those processes on the optical properties of XUV and soft X-ray irradiated Si$${_3}$$ 3 N$$_4$$ 4 , on sub-picosecond timescales. Si$${_3}$$ 3 N$$_4$$ 4 is a wide-gap insulating material widely used for FEL pulse diagnostics. Theoretical predictions are compared with the published results of two experiments at FERMI and LCLS facilities, and with our own recent measurement. The comparison indicates that three body Auger recombination strongly affects the optical response of Si$${_3}$$ 3 N$$_4$$ 4 after its collisional ionization stops. By deconvolving the contribution of Auger recombination, in future applications one could regain a high temporal resolution for the reconstruction of the FEL pulse properties measured with a Si$${_3}$$ 3 N$$_4$$ 4 -based diagnostics tool.

The dependences of the turbulent flame velocity in a random flow on the turbulence intensity have been studied in terms of the Kolmogorov–Petrovsky–Piskunov nonlinearity model in the one-dimensional case. We show that for a static random medium the turbulent velocity decreases and tends to zero with increasing turbulence intensity. This is explained by the fact that the random flow velocity is the random potential gradient, leading to traps and diffusion retardation. Apparently, this is a general fact: a random gradient velocity field in the two- and three-dimensional cases must give the same effect. This may be true not only for the Kolmogorov–Petrovsky–Piskunov nonlinearity. We have shown analytically that the introduction of a random nonzero mean velocity field accelerating the flame motion enables the flame to overcome the barriers more easily. For a dynamic medium an initial increase of the velocity with growing turbulence is possible in some ranges of scales in space and time. We consider an example of a two-dimensional random divergence-free field for which our numerical computation has shown an increase of the turbulent flame velocity.

The crystal structure of the new iodobismuthate (PyPy)2(PyPyH)2Bi6I26 was found to consist of unusual hexanuclear [Bi6I26]6− anions containing the linear I42− unit, and the experimental Bi–I bond lengths in this anion were used to obtain the relationship between bond length and bond energy. A statistical analysis of 229 crystal structures of iodobismuthates, based on the quantum chemically estimated strength of Bi–I bonds, revealed that the total energy of the Bi3+ polyhedron remains virtually constant at 64 ± 2 kcal mol−1, regardless of its geometry within this family of materials. Thus, the polyhedron geometry flexibly adapts to the relatively weak interactions between iodobismuthate anions and embedded cations.

—We performed a comprehensive study of basanites from the Daur–Hentiyn Range and present the first data on their Sr and Nd isotope and mineral compositions (electron probe microanalysis). The study has shown that the basanites are chemically similar to the volcanic rocks of the South Baikal volcanic area (SBVA) and are slightly different from oceanic island basalts in higher contents of Ba, Th, La, and Sr. The crystallization temperatures and pressures for the Fo0.85 olivine–melt equilibrium have been estimated, 1186–1137 ºC, 1.09–1.06 GPa, and the sequence of mineral crystallization has been established. The obtained Sr and Nd isotope data indicate that the basanitic magmas were generated from material with PREMA and EMI isotope parameters.

The article presents the results of research determining the most effective technologies for increasing metal yield in the processing of aluminum-containing waste. In particular, peculiarities of the processes of melting aluminum alloys were analyzed using complex methods of furnace and off-furnace processing of charge material containing an increased amount of shovelling scrap and swarf. Studies on the impact of charge preparation and aluminum remelting technology were carried out in SAT-0,16 and IAT-0,4 furnaces on the АК12М2 alloy. Experiments proved that batchwise loading 20 kg of swarf briquette preheated to 300–400 °C into the SAT-0,16 furnace with the addition of flux (composition: NaCl – 50 %; KCl –35 %, Na3AlF6 – 15 %) in the amount of 3 % of total metal mass is the most efficient technology. This technology makes it possible to achieve a metal yield of about 94 %. The study of the remelting technology influence on IAT-0,4 furnace metal yield showed that the greatest effect can be obtained in case of furnace charge (95 kg swarf briquette) by batches of 2 kg into the 7 kg liquid bath with modifier flux (composition: NaCl – 62 %; KCl – 13 %, NaF – 25 %) added in the amount of 2 % from the total metal mass. This technology provides up to 93.5 % of metal yield. Data from 10 series of 5–9 melts were also analyzed with the comparison of metal yield results depending on the mass of briquetted swarf charged into the furnace. A histogram of the change in the porosity of AK12M2 and AK9 samples depending on the content of swarf in the charge (from 0 to 45 %) during remelting. It was found that an increase in the content of swarf in the charge, all other things being equal, leads to an increase in the average porosity score, which indicates the need for additional refining of such melts.

We present the results of our identification of eight objects from the preliminary catalogue of X-ray sources detected in the 4–12 keV energy band by the Mikhail Pavlinsky ART-XC telescope onboard the SRG observatory during the first all-sky survey. Three of them (SRGA J005751.0+210846, SRGA J $$014157.0{-}032915$$ , SRGA J232446.8+440756) have been discovered by the ART-XC telescope, while five have already been known previously as X-ray sources, but their nature has remained unestablished. The last five sources have also been detected in soft X-rays by the eROSITA telescope of the SRG observatory. Our optical observations have been carried out at the 1.6-m AZT-33IK telescope of the Sayan Observatory and the 1.5-m Russian–Turkish telescope (RTT-150). All of the investigated objects have turned out to be active galactic nuclei (AGNs) at redshifts from 0.019 to 0.283. Six of them are Seyfert 2 galaxies (including one Seyfert 1.9 galaxy), one (SRGA J005751.0+210846) is a ‘‘hidden’’ AGN (in an edge-on galaxy), and one (SRGA J224125.9+760343) is a narrow-line Seyfert 1 galaxy. The latter object is characterized by a high X-ray luminosity ( $${\sim}(2-13)\times 10^{44}$$ erg s $${}^{-1}$$ in the 4–12 keV band) and, according to our black hole mass estimate ( $${\sim}2\times 10^{7}M_{\odot}$$ ), an accretion rate close to the Eddington limit. All three AGNs discovered by the ART-XC telescope (which are not detected by the eROSITA telescope) are characterized by a high absorption column density ( $$N_{\textrm{H}}\gtrsim 3\times 10^{23}$$ cm $${}^{-2}$$ ). The results obtained confirm the expectations that the ART-XC telescope is an efficient instrument in searching for heavily obscured and other interesting AGNs in the nearby ( $$z\lesssim 0.3$$ ) Universe. The SRG sky survey will last for another 3 years or more, which must allow many such objects to be discovered.

We present the results of our spectroscopic redshift measurements for galaxy clusters detected previously from Planck all-sky survey data as well as Sloan Digital Sky Survey and WISE all-sky survey data. The redshifts have been measured for 23 clusters, including four galaxy clusters from the second Planck catalogue of Sunyaev–Zeldovich sources. The main spectroscopic observations were carried out during 2019–early 2020 at the 1.6-m AZT-33IK telescope of the Sayan Observatory and the 1.5-m Russian–Turkish telescope (RTT-150). Some of the data have been obtained previously at the 3.5-m Calar Alto telescope. Out of the 23 clusters in this sample, 14 objects are located in the half of the sky where the rights to the data from the eROSITA sky survey onboard the SRG orbital X-ray observatory belong to the Russian side. All these clusters were detected with the eROSITA telescope in the course of the sky survey during 2020. On the whole, we have measured the spectroscopic redshifts for 220 galaxy clusters within our program of optical identifications of galaxy clusters from the Planck catalogue during several years. Many of them have already been detected in the SRG/eROSITA survey; a significant fraction of these objects are among the most massive galaxy clusters of the eROSITA sky survey and will most likely enter into cosmological samples of clusters from this survey.

A new FinDiff (Finite Difference) scheme with eliminated phase-lag and its derivatives up to order seven is introduced for the numerical approximation of problems in Quantum Chemistry.

Based on a generalized two-band Hamiltonian, the paper studies the formation of magnetic moment, energy spectrum and d-electron density of states of transition metals. It is shown that sd electron degeneracy in Hamiltonian results in the additional exchange-correlation energy of electrons, which in cooperation with the correlation energy determines the electronic structure of d-transition metals. In this case, the electron density of states has three peaks on the three-dimensional diagrams. And if the exchange-correlation energy is neglected, one peak disappears.

The effects of the dislocation density and of the concentration of vacancies in the β-solid solution on the processes of aging of intermetallic titanium alloy VTI-4 yielding a Ti2AlNb orthorhombic O-phase are studied. It is shown that the influence of the nonequilibrium concentration of vacancies in the solid solution is decisive for acceleration of the diffusion process and abrupt growth of the sizes of the O-phase. Preliminary deformation is shown to have a favorable effect on the deceleration of growth of the O-phase under subsequent aging.

В статье описывается топологическая структура замкнутых многообразий размерности не меньшей четырех, на которых существуют диффеоморфизмы Морса-Смейла такие, что их неблуждающее множество содержит произвольное число стоковых периодических точек, произвольное число источниковых периодических точек и две седловые периодические точки. Приводится также описание несущих многообразий диффеоморфизмов Морса-Смейла с меньшим числом седловых периодических точек. Библиография: 13 названий.

Effectiveness of economic development of logging industry is impossible without scientifically grounded strategies of formation of perspective technological logging processes with complex use of the total biomass of harvested trees. Degree of utilization of wood biomass is to be considered the most important principle of progressive logging technology. One of the main tasks of the national logging complex is the use of low-grade wood, lumpy wood waste, top of trees, twigs and branches, which will significantly improve efficiency of logging. To solve this problem, this article reviews the process of modeling of work of sorting and transportation machine designed for loading, sorting and transportation of felling residues to timber road. The technological scheme also provides cutting waste with knife for sorting by size. The study provides a detailed technological scheme of logging operations using forwarders with a removable body for loading, sorting and transportation of felling residues. The body of the forwarder is divided into compartments for transportation of waste with different parameters. The information and logical model of the process of collection, sorting and transportation of felling residue, which is proposed by machine, was offered. The formula for calculating the performance of operation of the sorting and transportation machine was obtained. Sorting according to species and types of felling residues is necessary for the production of fuel and technological wood chips for further use in production of valuable commercial products.

The main aim of the current study was to present the abilities of widely used crop models to simulate four different field crops (winter wheat, spring barley, silage maize and winter oilseed rape). The 13 models were tested under Central European conditions represented by three locations in the Czech Republic, selected using temperature and precipitation gradients for the target crops in this region. Based on observed crop phenology and yield from 1991 to 2010, performances of individual models and their ensemble were analyzed. Modelling of anthesis and maturity was generally best simulated by the ensemble median (EnsMED) compared to the ensemble mean and individual models. The yield was better simulated by the best models than estimated by an ensemble. Higher accuracy was achieved for spring crops, with the best results for silage maize, while the lowest accuracy was for winter oilseed rape according to the index of agreement (IA). Based on EnsMED, the root mean square errors (RMSEs) for yield was 1365 kg/ha for winter wheat, 1105 kg/ha for spring barley, 1861 kg/ha for silage maize and 969 kg/ha for winter oilseed rape. The AQUACROP and EPIC models performed best in terms of spread around the line of best fit (RMSE, IA). In some cases, the individual models failed. For crop rotation simulations, only models with reasonable accuracy (i.e. without failures) across all included crops within the target environment should be selected. Application crop models ensemble is one way to increase the accuracy of predictions, but lower variability of ensemble outputs was confirmed.

Shape and surface chemistry control in copper nanoparticle synthesis is an important research area due to a wide range of developing applications of this material in catalysis, energy conversion, sensing and many others. In addition to being an inexpensive and abundant metal, copper is an attractive photocatalyst due to its optical properties in the visible range. Here, we report a facile, tunable and sustainable methodology for synthesizing Pd-seeded Cu nanoparticles with various shapes, including cubes, spheres, raspberry-like particles and cages stabilized with a bilayer of a cationic surfactant in aqueous media. The experimental and theoretical examination of the optical response in the series of synthesized nanoparticles revealed that the low-energy extinction peak is associated with electronic interband transitions in the metal, in contrast to a widely spread attribution of this peak to a plasmonic response in Cu nanoparticles.

—The prototype of an apparatus for studying the X-ray fluorescence properties of nanomaterials for X-ray photodynamic therapy is developed. The X-ray fluorescence characteristics of nanomaterials based on gadolinium fluorides are studied. For a series of samples, X-ray fluorescence spectra are obtained in the region of 600–700 nm, which allows the conclusion that such materials are promising for use as components of radiosensitizers for X-ray photodynamic therapy. The data obtained are important for optimizing the characteristics of nanomaterials and for further modification of the parameters of methods for synthesizing new materials for X-ray photodynamic therapy.

Proton-conducting electrolytes (PCEs) have led to significant advances in the fields of solid-state ionics, energy conversion and high-temperature electrochemistry, providing the basis of various solid oxide devices that demonstrate outstanding performance and efficiency. Although the proton transport of PCEs has an undeniable advantage over the oxygen-ion transport of conventional complex oxide approaches, the refractory nature of these materials presents significant challenges for their fabrication in the form of thin films. In order to mitigate sintering conditions for multilayered PCE structures (single cells), various additives have been used. However, other fundamental and technological issues arise in this connection, including the localization of such introduced impurities near grain boundaries resulting in blocked proton transportation. The present article reports a general strategy for effectively sintering PCE-based refractory materials while maintaining their hydrogen transportation, using a BaSn0.8Sc0.2O3−δ model compound due to its significant water uptake even at high levels of acceptor doping. This strategy, as shown in a comprehensive analysis of corresponding experimental results, proposes a CuO sintering additive in low amounts, sufficient for achieving a dense state with no adverse effects on protonic conduction. The reported findings can be applied for scalable preparation of gas tight PCEs at reduced sintering temperatures for various electrochemical purposes.

In the past decade, intensive research on proton-conducting oxide materials has provided a basis for the development of intermediate-temperature protonic ceramic electrochemical cells, which constitute a real alternative to conventional cells based on oxygen-conducting electrolytes. To achieve both high efficiency and excellent performance, not only electrolytes but also electrode materials should be carefully selected considering their functional properties. Compared to the traditional ABO3 perovskite electrode materials, Ln2NiO4+δ with a layered structure has unique advantages (high chemical stability, mechanical compatibility, improved oxygen transport, and hydration ability), and thus is now becoming a hot topic in this field, offering both scientific and practical interests. However, a comprehensive and in-depth review is still lacking in the literature to date. Accordingly, this work presents a comprehensive overview of the prospects of layered nickelates (Ln2NiO4+δ, where Ln = La, Nd, and Pr) as one of the most attractive oxygen (steam) electrode materials for protonic ceramic electrochemical cells. In particular, the crystalline features, defect structure, stability, chemical properties, and mechanical compatibility of this class of materials, contributing to their transport functionality, are discussed with the primary emphasis on revealing the relationship between the composition of the materials and their properties. The presented systematic results reveal the main strategies regarding the utilisation of Ln2NiO4+δ-based electrodes and existing gaps related to fundamental and applied research aspects.

Hydrogen bond donors (HBDs) are a sustainable privileged class of catalysts which are broadly used for the activation of compounds in synthetic chemistry. Among them, the metal-templated HBD complexes present perspective systems with high catalytic potential. In this respect, here we report the design of the next-generation octahedral Co(III) complexes based on cheap commercially available 1,2-phenylenediamine and 3,5-di-tert-butyl-salicylaldehyde. It was shown that the obtained Co(III) complex with an iodide counter-anion operates as a bifunctional one-component hydrogen bond donor/nucleophilic catalyst for the fixation of carbon dioxide with epoxides into valuable cyclic carbonates under ambient conditions (RT and 1 bar CO2) and solvent- and co-catalyst-free conditions. The TON and TOF values of 38 and 1.6, respectively, were achieved at a low catalyst loading (2 mol%) under ambient conditions. Furthermore, the obtained Co(III) complex catalyzed the reaction with a diluted air/CO2 mixture (15 vol% of CO2) producing the desired cyclic carbonate in a 92% yield. A plausible catalytic cycle consistent with all experimental observations was proposed based on DFT calculations. The epoxide-opening step was found to be the rate-determining step. Besides, the influence of different additives on the catalysis was investigated and explained computationally.

We present an easy and at the same time effective computational algorithm for tracing the interferograms of phase objects. The approach to preprocessing of interference patterns, which includes image denoising and removal of distortions, is given. We provide a detailed description of the parabola method involved in the algorithm for searching candidates for extreme points and consider the criteria for their selection and drawing lines connecting such points, i.e., the traces of the interference fringes. The advantages and disadvantages of the method, when applied to the study of complex-structured phase objects such as spark channels, which are formed during electrical discharges in ambient air, are discussed.

Рассматривается класс регулярных гомеоморфизмов Смейла, неблуждающее множество которых состоит из конечного числа периодических орбит, имеющих гиперболический тип, на замкнутых топологических многообразиях. Этот класс содержит диффеоморфизмы Морса-Смейла на замкнутых гладких многообразиях. Для регулярных гомеоморфизмов Смейла приводятся необходимые и достаточные условия сопряженности. Библиография: 26 названий.

The taxonomic diversity, distribution patterns, and host-parasite relationships of fleas of the Holarctic genus Rhadinopsylla (Hystrichopsyllidae: Rhadinopsyllinae) are analyzed. The role of some members of this genus as vectors and reservoirs in natural plague foci of Eurasia is considered; 18 out of 70 species and subspecies of the genus Rhadinopsylla have been recorded as the main, accessory, or occasional vectors of the plague pathogen.

In the field-effect transistors based on the wide-band-gap nitride heterostructures, the dielectric layers are in widespread use as one of the main elements in the active regions of the devices and the passivation layers. Stringent requirements are imposed on the dielectrics in terms of the high dielectric capacitance, large band-gap energy, and the coating integrity. Furthermore, the films must withstand high electric fields and have a low surface state density in the dielectric/semiconductor interface. For these purposes, the low temperature films grown by plasma-enhanced chemical vapor deposition, atomic layer deposition (ALD), and plasma-enhanced deposition are usually used as effective coatings. The ALD films of Al2О3, SiNх (Si3N4), SiON, and ALD AlN are used most often, and offer the greatest promise for the AlGaN/GaN heterostructures. The influence of the passivation of the ALD Al2O3, SiNx, and SiON coatings of various thicknesses on the change of the charge and the density of the states of the AlGaN/GaN heterostructures is investigated. The physical parameters of the structures are estimated by the C–V characteristics measured on various frequencies and the I–V characteristics. It is demonstrated, according to the examined energy band diagrams of the structures at various control voltages, and estimation of the elemental composition of the films by the method of Auger electron spectroscopy, that the reason for the generation of a high positive charge at the deposition of the ALD Al2O3 and SiNx films is the occurrence of an additional piezoelectric charge in the buffer layer of AlGaN. It is demonstrated that use of the SiON films with the oxygen concentration in them higher than 3% does not result in the generation of an additional positive charge but can initiate current fluctuations during the measurement of the I–V characteristics. A possible mechanism of carrier transport in the space charge region resulting in such fluctuations is discussed.

This paper is a review of current concepts concerning the seismotectonics and seismicity in the Laptev Sea region. The chief feature of the region is a rift system extending in the shelf from the continental slope with the adjacent Gakkel Ridge to the mainland coast. There are several models to describe the present-day evolution of the region, but no one of these is preferable because of the lack of local instrumental observations of shelf microseismicity, while such microseismicity is characteristic of rift zones. One alternative approach consists in the installation of ocean bottom seismometers on the shelf itself. During the 73rd cruise of the R/V Akademik Mstislav Keldysh, a temporary network was deployed consisting of 7 broadband bottom seismic stations on the Laptev Sea shelf. Comparative analysis of noise spectra based on records of a hydrophone, a bottom seismograph, and a wavegauge, showed that the noise amplitude strongly depends on wind waves, which is in turn dependent on marine ice cover, so that the recording potential of a local network of bottom seismographs is restricted to the winter period of observation.

A problem formulation is proposed for simulating lean premixed hydrogen–air combustion in a closed volume with numerically generated turbulence. Two-dimensional simulations of flame propagation from a small ignition kernel showed that the following sequence of regimes is observed with increasing turbulence intensity and decreasing mixture strength: a corrugated flame with a continuously connected front, a regime with a local loss of front connectivity, and flame extinction through disintegration of a growing kernel into fragments. The transition from steady self-sustained combustion to extinction corresponds to changes in mixture and turbulence parameters leading to a stronger influence of turbulent velocity field on local flame structure. The proposed approach to numerical simulation of the transition regime characterized by loss of front connectivity and fragmentation of the flame under the action of turbulent eddies can be used to evaluate the effect of turbulence intensity on flammability limits.

The heterogeneity of the structural state of a VT41 pseudo-α-titanium alloy after hot upset is studied. The analysis of the distribution of deformation upon upset and characteristic features of the formation of each of the structural components of the specimen is performed. Globular grains are deformed by the mechanism of intergranular slipping. β grains and α plates make the greatest contribution to plastic deformation. Lamellar grains of the α phase undergo recrystallization in the zone of localization of deformation. The dimensions of the zone where the recrystallization occurs coincide with the zone of localization of deformation estimated by the macrostructure. When quenching the billet, the β phase breaks down into α plates in the center of the specimen and into smaller grains that probably are needle-like β-titanium martensite in the near-surface regions. A decrease in the microhardness in the central regions may be due to both recrystallization and the fact that the surface layers are subjected to martensite quenching.

In experiments using cylindrical and conical shock tubes, the parameters of the shock-wave load transmitted to the rigid wall through the layers of a nonwoven covering made of aramid fibers are determined. The effect of amplifying the amplitude of the pressure wave depending on the layer’s thickness is demonstrated. The developed experimental modeling technique and the results obtained show that a conical shock tube is an effective tool for studying the interaction of spherical shock waves (SWs) with layers of explosion-proof coatings.

The algorithms of model reference parametric adaptation are considered, providing the astaticism and disturbances estimation. The structure of the control system is suggested allowing to design multivariable controllers providing the movement along the specified trajectories for an object described by kinematics and dynamics of mechanical systems in three-dimensional space. The asymptotic stability of a closed-loop adaptive system including a loop to provide astaticism is proved by the method of Lyapunov functions. The errors analysis is carried out of disturbances estimation by asymptotic observer. The boundaries of the estimation error are shown, and the relations are given to adjust the observer parameters. The results of the numerical investigations are given.

Simulations of autoignition of stoichiometric С2Н2/О2 and СН4/О2 mixtures were performed in the temperature and pressure ranges of 800 < T < 2100 K and 0.02 < P < 1.1 MPa using various detailed kinetic mechanisms (DKMs) presented in the literature. The ignition delays predicted by DKMs were compared to choose the optimum value for reduction. The number of species in the DKM was reduced by a trial-and-error method based on an analysis of ignition delay response to the removal of species. The automatic computer code developed in this study made it possible to reduce the number of species more than twofold for C2H2/O2 and threefold for CH4/O2. A comparison of predictions based on the reduced kinetic mechanisms with experimental data presented in the literature showed good agreement for С2Н2/О2 and СН4/О2 mixtures with different argon dilutions.

The paper presents the results of drop tests performed to measure ignition delay for ionic liquids under various experimental conditions. Factors that strongly affect correct determination of ignition delay are indicated. Processes preceding ignition upon contact between various quantities of a fuel and an oxidizer are explained. It is argued that well-defined experimental conditions are required to ensure correct comparison when using benchmark fuels.

Significance The male-specific Y chromosome harbors genes important for sperm production. Because Y is repetitive, its DNA sequence was deciphered for only a few species, and its evolution remains elusive. Here we compared the Y chromosomes of great apes (human, chimpanzee, bonobo, gorilla, and orangutan) and found that many of their repetitive sequences and multicopy genes were likely already present in their common ancestor. Y repeats had increased intrachromosomal contacts, which might facilitate preservation of genes and gene regulatory elements. Chimpanzee and bonobo, experiencing high sperm competition, underwent many DNA changes and gene losses on the Y. Our research is significant for understanding the role of the Y chromosome in reproduction of nonhuman great apes, all of which are endangered., The mammalian male-specific Y chromosome plays a critical role in sex determination and male fertility. However, because of its repetitive and haploid nature, it is frequently absent from genome assemblies and remains enigmatic. The Y chromosomes of great apes represent a particular puzzle: their gene content is more similar between human and gorilla than between human and chimpanzee, even though human and chimpanzee share a more recent common ancestor. To solve this puzzle, here we constructed a dataset including Ys from all extant great ape genera. We generated assemblies of bonobo and orangutan Ys from short and long sequencing reads and aligned them with the publicly available human, chimpanzee, and gorilla Y assemblies. Analyzing this dataset, we found that the genus Pan, which includes chimpanzee and bonobo, experienced accelerated substitution rates. Pan also exhibited elevated gene death rates. These observations are consistent with high levels of sperm competition in Pan. Furthermore, we inferred that the great ape common ancestor already possessed multicopy sequences homologous to most human and chimpanzee palindromes. Nonetheless, each species also acquired distinct ampliconic sequences. We also detected increased chromatin contacts between and within palindromes (from Hi-C data), likely facilitating gene conversion and structural rearrangements. Our results highlight the dynamic mode of Y chromosome evolution and open avenues for studies of male-specific dispersal in endangered great ape species.

Results of the first spectroscopic observations at the 1.5-m Russian–Turkish telescope for the X-ray sources discovered by the eROSITA telescope onboard the SRG space observatory and identified by the SRGz machine learning system as candidates for distant X-ray quasars are presented. Seven objects have been confirmed as quasars at redshifts $$z=2.7{-}4.2$$ and two sources, which were included in the program of optical observations aimed at testing and adjusting SRGz and had a significant uncertainty in the photometric redshift, have turned out to be Seyfert galaxies at $$z\approx 0.6$$ .

The evolution of the Northern Hemisphere oceanic gateways has facilitated ocean circulation changes and may have influenced climatic variations in the Cenozoic time (66 Ma–0 Ma). However, the timing of these oceanic gateway events is poorly constrained and is often neglected in global paleobathymetric reconstructions. We have therefore re-evaluated the evolution of the Northern hemisphere oceanic gateways (i.e. the Fram Strait, Greenland–Scotland Ridge, the Central American Seaway, and the Tethys Seaway) and embedded their tectonic histories in a new global paleobathymetry and topography model for the Cenozoic time. Our new paleobathymetry model incorporates Northeast Atlantic paleobathymetric variations due to Iceland mantle plume activity, updated regional plate kinematics, and models for the oceanic lithospheric age, sediment thickness, and reconstructed oceanic plateaus and microcontinents. We also provide a global paleotopography model based on new and previously published regional models. In particular, the new model documents important bathymetric changes in the Northeast Atlantic and in the Tethys Seaway near the Eocene–Oligocene transition (~34 Ma), the time of the first glaciations of Antarctica, believed to be triggered by the opening of the Southern Ocean gateways (i.e. the Drake Passage and the Tasman Gateway) and subsequent Antarctic Circumpolar Current initiation. Our new model can be used to test whether the Northern Hemisphere gateways could have also played an important role modulating ocean circulation and climate at that time. In addition, we provide a set of realistic global bathymetric and topographic reconstructions for the Cenozoic time at one million-year interval for further use in paleo-ocean circulation and climate models. publishedVersion

Trinuclear copper(I) pyrazolate [Cu(3,5-(CF3)2Pz)]3 was employed in a mechanistic study of azide-alkyne cycloaddition (CuAAC). It was shown that the copper complex operates as a bifunctional catalytic system (copper source and Bronsted base) under mild conditions (RT and air atmosphere) at low catalyst loading (1 mol%). The rate-determining step of the reaction is the first C-N bond formation between azide and acetylene (azide migratory insertion) but not the copper(I) acetylide formation as commonly assumed. It was supported by the observed kinetic isotope effect equaling 1.1 and by DFT calculations. The reaction has a second-order dependence on the catalyst concentration implicating the two copper(I) centers participate in the metallacycle formation step from “bis-butterfly” tetranuclear complex Cu4L4(RC≡CH)2 in the rate-determining step. DFT calculations proved that the pyrazolate ligand acts as a Bronsted base and deprotonates the acetylene molecule providing successful catalysis. A plausible catalytic cycle of the reaction has constructed based on DFT calculations.

In ichthyological publications from both Russia as a whole, and from the study region, lack of data indicating the actual results of observations in a specific place all result in publication of a generalised analysis. Although our publications contain such data, they are, however, not convenient for users performing global analysis. The main purpose of publishing a database is to make our data available in the global biodiversity system to a wide range of users. Dataset represents a significant addition to the distribution of species in this area. The data can be used to analyse future changes in ichthyofauna, as well as to help the authorities to manage their territory more efficiently.This publication describes a dataset that contains information on fish encounters in the Upper Don basin and the middle Volga (centre of the European part of Russia) over a 30-year period (1990-2020). The dataset contains information on 6400 occurrences of 394341 specimens of 56 species, 99.9% of specimens being identified to the species level. A total of 883 sites were studied, of which 253 were in lentic biotopes (lakes - 121, ponds - 123, backwater - 5, reservoir - 3, pit - 1), 630 were in lotic (rivers - 628, stream - 1, channel - 1). One collecting site has an average of 7.2 species (from 1-21 species per location). Only those species that form self-reproducing populations are given. The dataset is a compilation of data from several working author groups. All observations have precise geo-referencing with the names of water bodies (rivers, lakes etc.). All presented data are published in the form of a database for the first time. Some data form the basis of previously-published works (3998 observations, 62%) and some are published for the first time (2402 observations, 38%). A large amount of data comes from small water bodies that have been neglected by previous researchers.