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Summary Pathogenic fungi cause major postharvest losses. During storage and ripening, fruit becomes highly susceptible to fungi that cause postharvest disease. Fungicides are effective treatments to limit disease. However, due to increased public concern for their possible side effects, there is a need to develop new strategies to control postharvest fungal pathogens. Botrytis cinerea, a common postharvest pathogen, was shown to uptake small double‐stranded RNA (dsRNA) molecules from the host plant. Such dsRNA can regulate gene expression through the RNA interference system. This work aimed to develop a synthetic dsRNA simultaneously targeting three essential transcripts active in the fungal ergosterol biosynthesis pathway (dsRNA‐ERG). Our results show initial uptake of dsRNA in the emergence zone of the germination tube that spreads throughout the fungus and results in down‐regulation of all three targeted transcripts. Application of dsRNA‐ERG decreased B. cinerea germination and growth in in vitro conditions and various fruits, leading to reduce grey‐mould decay. The inhibition of growth or decay was reversed by the addition of ergosterol. While dual treatment with dsRNA‐ERG and ergosterol‐inhibitor fungicide reduced by 100‐fold the required amount of fungicide to achieve the same protection rate. The application of dsRNA‐ERG induced systemic protection as shown by decreased decay development at inoculation points distant from the treatment point in tomato and pepper fruits. Overall, this study suggests that dsRNA‐ERG can effectively control B. cinerea growth and grey‐mould development suggesting its efficacy as a future method for postharvest control of fungal pathogens.

Background. Decline of oil and gas traditional reserves pushes companies to explore and involve in production complex reservoirs which results in exploration risks increase. That is why an exploration research has to be integrational and its’ main result has to be determination and decreasing uncertainties. Aim. The aim of this research is the planning of further exploration program within the studied territory, based on the main uncertainties and trends in geological development. Materials and methods. Several types of research methods were applied, including field observation, laboratory analysis and geological desktop studies. The results of petroleum systems modeling is the basis for source rocks maturity prediction, the main stages of hydrocarbons generation — migration and critical moment estimation. It also provided the analysis of migration distance (limits) and geological risks related to it, petroleum saturation prediction for the main plays. Great emphasis was also placed on the search and processing of additional archival data, which made it possible to significantly detail the structural-tectonic framework of the studied area. Results. Consistent progression in field observation, laboratory analysis and geological desktop studies allowed to narrow the range of uncertainties, clarify the chance of geological success (gCOS), plan the further exploration program, and highlight higher-priority license blocks. As a result, more than 60 additional prospects were identified, for each of them both the probabilistic estimation of oil and gas resources and chance of geological success evaluation were made. Moreover, the further exploration program was approved. Conclusions. Therefore, the study allowed to analyse main uncertainties and correct further exploration program on the basis of integrated analysis of geological development history and geological structure of the studied area.

The electrochemical dissolution (destruction) of zirconium and zirconium alloy (fuel rod cladding) in nitric acid solutions was studied. The dependences of the dissolution rate on the concentration of nitric acid, temperature, and composition of the electrolyte were determined. The maximum dissolution rate of the samples is observed in dilute nitric acid at elevated temperatures. The surface oxide film on the samples and the precipitates formed during dissolution were analyzed. It was proposed to use the destruction products of zirconium-based claddings of fuel rods for the synthesis of matrix materials and immobilization of fission products formed in the spent nuclear fuel.

We present information on ozone concentration in the surface air layer in the second half of 2020. Data were obtained at 13 stations located in different regions of Russia. We estimated the excess over hygienic standards of the Russian Federation, both in the second half of the year and throughout 2020. It is shown that the daily average maximum permissible concentration of ozone is regularly exceeded at all stations. There are cases of exceeding the one-time maximum permissible concentration.

Methyl 12-oxo-6,12-dihydroazepino[2,1-b]quinazoline-8-carboxylate and methyl 3H-azepin-2(1H)-one-5-carboxylate were synthesized by photoinduced heterocyclization of methyl 4-azidobenzoate and ethyl 2-aminobenzoate in the THF–water and acetonitrile­–water mixtures. It was found that the yields of methyl 12-oxo-6,12-dihydroazepino[2,1-b]quinazolate increase with rising water content in the reaction mixture.

The effect of an organo-aqueous solvent on the yields of 12-oxo-6,12-dihydroazepino[2,1-b]quinazoline-6-carboxylic acid methyl ester and 3H-azepine-2(1H)-one-3-carboxylic acid methyl ester has been evaluated. It has been found that at low concentrations, water competes with 2-aminobenzoic acid ethyl ester in the nucleophilic addition reaction, reducing the yields of azepino[2,1-b]quinazolinone and increasing the yields of 3H-azepinone. At a water concentration of more than 20 wt %, the nucleophilicity of substituted aniline increases, contributing to an increase in the yields of azepino[2,1-b]quinazolinone and a decrease in the yields of 3H-azepinone.

Adsorption of Cu(II), Co(II), Cd(II), Ni(II), Pb(II), Zn(II) and Fe(III) ions from aqueous solutions of their salts on the surface of pine sawdust in situ immobilized by polyaniline has been studied under static mode at various pH values. The adsorption of all the ions has been found to increase as the pH value grows. The sawdust in situ immobilized by polyaniline has been shown to adsorb as much as 56 mg/g of Fe(III) ions from slightly alkaline solutions (pH 8) within just the first several minutes of the experiment which could be used for the purification of industrial waste solutions from these ions. Such composites based on the sawdust in situ modified by polyaniline could also be potential adsorbents for purification of national water resourced contaminated by Pb(II) and Cd(II) in slightly alkaline solutions (pH 8) to reach their limit concentrations.

The subthreshold self-non-self-sustained discharge in air was studied as the basis of the system for cleaning urban air from ecologically harmful admixtures. A cycle of experiments was carried out and the efficiency of the destruction of small amounts of hydrogen sulfide mixed with air (about 8 ppm) introduced into the processed air volume was determined. Experiments demonstrated a relatively high degree of H2S decomposition (its concentration decreased 41.5 times at unit energy deposition of 8 J/cm3 in the SNSS discharge).

Lines of various forms of stimulated scattering have been revealed in the scattering spectrum excited by pulsed second-harmonic radiation of a YAG:Nd3+ laser in an initially homogeneous aqueous colloidal solution (suspension) of polystyrene nanoballs. Dynamic light scattering measurements have shown that the laser-stimulated coagulation of some nanoballs with the formation of particles with an order-of-magnitude larger size occurs in the solution. An explanation of this phenomenon has been proposed.

Charge transfer complexes (CTCs) are obtained by the interaction of 9,10-phenanthrenequinone nitro derivatives with anthracene. By electron spectroscopy it is established that the acceptor properties of the former increase with increasing number of nitro groups and depend on their position. 1,3,6-Trinitro-9,10-phenanthrenequinone, which forms with anthracene a CTC with a charge transfer band near 658 nm, is found to be the strongest acceptor. Charge transfer values from the donor (D) to the acceptor (A), ranging from 0.034 ē to 0.091 ē, formation energies of [A–D] complexes, HOMO and LUMO gaps in CTC are found by quantum chemical calculations, and they correlate with the experimental positions of long-wave bands in the electron absorption spectra of the complexes in solutions. The crystal and molecular structures of new 1:1 CTC of 2,4,7-trinitro-9,10-phenanthrenequinone with anthracene is determined by single crystal X-ray diffraction. In crystal, CTC has a {⋯[A–D]⋯[A–D]′⋯}∞ packing of the mixed type where average interplanar distances are 3.35 A, with the shortest C⋯C distance being 3.234(2) A, and intermolecular C–H⋯O hydrogen bonds are in the range 2.50-2.69 A.

The effect of the loading rate and temperature on the damage of pipe steels in environments containing hydrogen sulfide and carbon dioxide is studied. The results of accelerated tests at slow deformation rate for the resistance of steels to stress corrosion cracking are analyzed. The deformation rate is justified for conducting reliable tests for stress corrosion cracking and temperature effect on pipe steels is revealed. The criteria for the tendency assessing of pipe steels to stress corrosion cracking in accelerated tests are the fracture stress or the ratio of stresses in corrosive environment and in air and the elongation or the ratio of elongations in corrosive environment and in air.

Information on the ozone concentration in the surface air and troposphere in the first half of 2020 is presented. The data were acquired at 13 stations in different Russian regions; vertical distributions were obtained with the use of an aircraft laboratory. The excess over the Russian Federation hygienic standards is assessed; the daily average ozone concentration is found to be regularly higher the maximum permissible concentrations at most stations. At some stations, there are features the seasonal variations in the ozone concentration in the period under study different from previous years.

AIM To study the efficacy and safety of using sildenafil in patients with erectile dysfunction (ED) and concomitant cardiovascular diseases (CVD) who underwent transurethral resection of the prostate (TURP). MATERIAL AND METHODS A total of 59 patients (age from 50 to 75 years) with a diagnosis of benign prostatic hyperplasia (BPH), requiring surgical treatment due to inefficiency of drug therapy, I-PSS score more than 20 points), who were sexually active, but had erectile dysfunction (IIEF score < 21), coronary heart disease (NYHA class I) and stage 1-2 hypertension with stable blood pressure. All patients underwent bipolar TURP. From the first day after the TURP, therapy was prescribed as following: tamsulosin 0.4 mg once a day for 90 days, ciprofloxacin 500 mg twice a day for 10 days. In addition, the patients received treatment for comorbidities. In the main group (n=30), men additionally received sildenafil (EFFEX Sildenafil Evalar) 50 mg daily for 60 days, starting from the 30th day postoperatively. We have chosen this drug from an economic standpoint. RESULTS At baseline, all patients in both groups had hemodynamic and microcirculatory disorders in the prostate, which got worse in the early postoperative period. During the long-term follow-up, hemodynamic and microcirculatory impairments decreased. This effect was more pronounced in patients who received sildenafil. In addition, patients had an improvement in sexual function. During follow-up, there was no adverse effects of sildenafil on hemodynamic parameters (blood pressure, heart rate). CONCLUSION Our results allow to recommend sildenafil in order to restore sexual function postoperatively in patients with BPH, including those with concomitant cardiovascular disorders.

The main evolution stages of the phase diagram of Fe–C in the carbide region (on the right from the cementite line) is a recently discussed theoretical topic that has been considered. It has been determined that previously isolated e-Fe2C, χ-Fe5C2, and g-Fe7C3 carbides (except for cementite Θ-Fe3C) are nonstoichiometric compounds. Thus, they are variable composition phases containing stoichiometric composition or second-type interstitial solid solutions based on daltonides and berthollides. It has been stated that the iron–cementite phase diagram can be identified as the iron–e-Fe2C carbide phase diagram in the concentration range of 0–9.7% C. The following phase transformations are introduced to the diagram: reaction of nonvariant syntectic equilibrium of cementite Θ-Fe3C crystallization; reaction of peritectic equilibrium of carbide χ-Fe5C2 crystallization; low-temperature peritectoid transformation of carbide, at which solid solutions of ferrite and cementite form solid solution possessing broad homogeneity range based on e-carbide Fe2C berthollide. It has been shown that the carbide phases represent a uniform isomorphous quasi-carbide solid solution, while the carbide phase crystallizes in the form of the carbide phase mixture as quasi-eutectics.

Analytical expressions for the dispersion of electron bands are obtained by the method of Green’s functions in the tight-binding approximation. A parabolic approximation of the spectrum is proposed, within the framework of which the values of the effective mass of carriers and the quantum capacity are determined. The problem of local states of defects is considered using the Koster–Slater and Haldane–Anderson models. Analytical estimates of the characteristic phonon frequencies and elastic constants are given. The results are compared with the calculated data of other authors.

The electrochemical noise of a system of two identical steel electrodes in the NaCl solution without and with an addition of benzotriazole (BTA) corrosion inhibitor is measured and analyzed. It is shown that this method is a convenient tool for testing the protective properties of inhibitor. The method of impedance spectroscopy applied to this electrochemical system gives the information on the mechanism of inhibitor action.

We present the results of a large-scale study of carbon dioxide and methane distributions carried out on the territory of Western Siberia in 2018–2019 using a Picarro G4301 portable gas analyzer. The analysis of the data made it possible to retrieve the spatial distribution of background CO2 and CH4 concentrations with a high resolution. The inhomogeneities found in the CO2 and CH4 distributions were both due to the effect of ecosystems characteristic for different regions of Western Siberia and to specific features of their seasonal cycles.

In the context of Haldane–Anderson’s model, the transferred charge and the energy of adsorption of alkali metal and halogen atoms on the C and Si faces of the 3C-, 6H-, and 4H-SiC polytypes are estimated. The contributions of the band and local states to the formation of the charge of adatoms and the metallic and ionic components of the adsorption energy are clarified.

In this paper, we studied the interrelation between the variations in CH4, CO, CO2, NO, NO2, O3, and SO2 concentrations, and the number concentration of aerosol with particle diameters larger than 0.4 μm, and the following meteorological parameters: air temperature, atmospheric pressure, wind direction and speed, total solar radiation and ultraviolet radiation in the wavelength range 295–320 nm, relative humidity, and partial water vapor pressure. For this, we used the air composition monitoring data (for the period 1993–2018) from the Tropospheric Ozone Research (TOR) station in the region of Tomsk Akademgorodok.

To estimate the physical characteristics of cubic boron arsenide, Keating’s model of force constants and Harrison’s method of bonding orbitals are used. The harmonic and anharmonic characteristics are considered. Comparison of the results with experimental data and other calculations shows the adequate applicability of the approach.

The formation of iron silicide thin films under graphene grown on the silicon carbide surface is investigated. The thin films are synthesized by consecutive intercalation of iron and silicon atoms into the graphene. Experiments are carried out in situ in ultrahigh vacuum. The elemental composition and chemical state of the surface of prepared samples and their atomic structure are determined by low-energy electron diffraction and high-resolution X-ray photoelectron spectroscopy using synchrotron radiation. The thickness of deposited iron and silicon layers varies in the range of 0.1–2 nm, and the sample annealing temperature is varied from room temperature to 600°C. We show that intercalation of silicon into the graphene/Fe/SiC system leads to the formation of a layer of Fe–Si solid solution coated with the surface silicide Fe3Si. The films are effectively protected by graphene from exposure to ambient environment, which opens possibilities for their practical application.

An agreement between the content of amorphous (oxalate-extractable) iron and morphochromatic features of gley attests to the modern activity of gleyzation processes in tundra soils of the Kolyma Lowland, especially within lower parts of gentle and steep slopes. A suprapermafrost reduced gley horizon thawing out in the warmest years is considered a relic of the warmer and wetter stage of soil formation. An integrated analysis of data on the contents of mobile iron and annotated metagenomes indicates that microorganisms affiliated with the Proteobacteria phylum capable of iron reduction predominate in sediments formed under hydromorphic conditions and in modern mineral soil. In laboratory experiments, the process of microbial iron reduction was more active at 5°C than at 20°C. Therefore, it can be assumed that the majority of cultivated communities of iron-reducing bacteria have been adapted to low Arctic temperatures. Under conditions of climate warming and an increase in precipitation, permafrost temperature, and thickness of the seasonally thawed layer, iron reduction processes in the soils rich in the total iron will play an even greater role and create favorable redox conditions for the formation of methane, one of the most important greenhouse gases.

Data on the structure and properties of charge transfer complexes of nitro derivatives of 9,10-phenanthrenequinone (acceptor) with phenanthrene (donor) were obtained by quantum chemical calculations. The energies of complex formation, the average distances between donor and acceptor planes, and the total charge transfer amounts were calculated. 1,3,6-Trinitro-9,10-phenanthrenequinone was shown to be the strongest acceptor in the studied series. The crystal and molecular structure of the 1 : 1 complex of 2,4,7-trinitro-9,10-phenanthrenequinone with phenanthrene [C14H5N3O8·C14H10] was determined by X-ray structural analysis.

Metallographic studies of annealed medium-carbon steels (45, 40Kh, and 35KhGSA) showed that there is low-temperature peritectoid carbide transformation of pearlite of these steels, in which solid solutions of ferrite and cementite form solid solution with a broad homogeneity range on the basis of e-carbide Fe2C. It was suggested to plot the horizontal line of peritectoid transformation at the temperature of 382°C and the horizontal line of peritectoid transformation of cementite at 1650°C on the Fe–C diagram of state.

Propagation velocity of a subthreshold microwave discharge in air and carbon dioxide is measured at various gas pressures and intensities of microwave radiation. At air pressures of 200, 390, and 738 Torr and carbon dioxide pressures of 390 and 750 Torr, the propagation velocity of the head part of the self-non-self-sustained discharge closely follows a quadratic power law as a function of microwave-beam intensity in the range from 4 to 16 kW/cm2, while decreasing directly proportional to the initial gas density. In the process, the discharge propagation velocities in carbon dioxide are twice lower that those in air at equal intensities of the microwave radiation. The temperature in the head part of the discharge in air reaches 3.5–5.5 kK, while that in carbon dioxide reaches 9–15 kK.

The Ti-Al-Zr-O system has received significant attention as it hosts a variety of phases of industrial interest. In this paper, new experiments on the Ti-Al-Zr-O system aimed at clarifying phase formation depending on the redox conditions with special attention to the formation of ternary compounds and their results have been reported. For the first time a monophase AlTi2O5 sample with a ratio of titanium oxides TiO2:Ti2O3 = 2:1 was obtained and characterized. Single-crystal X-ray diffraction analysis of β-(ZrxTi1-x)2O4 crystals was carried out. The synthesis of the ternary Ti-Al-Zr compound was performed in an evacuated quartz ampoule and accompanied by the extraction of silicon from the ampoule. The compound has pyrochlore-type cubic structure A24+B23+O7 (Fd-3m) and the composition close to (Ti4+1,47(2)Zr0.41(2)Si0.12(1))2(Al1.15(4)Ti3+0.85(4))2O7. We believe that our study is a starting point for future research as it provides first experimental data on the ternary compound in the Ti-Al-Zr-O system.

Quantum capacitance CQ of an infinite graphene sheet, a graphene nanoribbon, and a chain of carbon atoms (carbyne) have been analytically estimated within the framework of simple models. A nonmonotonic dependence of CQ on the electrostatic potential is demonstrated. The data obtained are compared with the calculation results of other researchers.

Barium fluoride (BaF2) crystals are considered as a candidate scintillator for scintillation detectors in high-energy physics because of high radiation hardness and short decay time (< 1 ns) of the fast emission component. However, the high level of the slow emission component can deteriorate the detector time resolution. Special approaches are required to decrease this slow component. Using solar-blind photodetectors is one of the possible solutions. In this article, we describe a solar-blind photomultiplier with microchannel plates (MCP) that uses an aluminum gallium nitride (AlGaN) photocathode and a complete scintillation detector channel with a BaF2 crystal and the photomultiplier. The results of the cosmic-ray tests are presented that show the efficiency of detection of the BaF2 fast emission component and suppression of the slow one in the proposed scintillation detector.

Partial funding for Open Access provided by the UMD Libraries' Open Access Publishing Fund., Structural phase transitions serve as the basis for many functional applications including shape memory alloys (SMAs), switches based on metal-insulator transitions (MITs), etc. In such materials, lattice incompatibility between transformed and parent phases often results in a thermal hysteresis, which is intimately tied to degradation of reversibility of the transformation. The non-linear theory of martensite suggests that the hysteresis of a martensitic phase transformation is solely determined by the lattice constants, and the conditions proposed for geometrical compatibility have been successfully applied to minimizing the hysteresis in SMAs. Here, we apply the non-linear theory to a correlated oxide system (V1−xWxO2), and show that the hysteresis of the MIT in the system can be directly tuned by adjusting the lattice constants of the phases. The results underscore the profound influence structural compatibility has on intrinsic electronic properties, and indicate that the theory provides a universal guidance for optimizing phase transforming materials.

Analytical expressions for the band gaps and characteristic velocities and effective masses of carriers are obtained for infinite flat sheets, free and decorated nanoribbons with zigzag edges, and chains of aluminum and gallium nitrides. The values obtained are compared with the characteristics for silicon carbide and carbon nanostructures calculated within the same models. The role of the substrate is also briefly discussed.

Using the Green’s function method within the tight-binding approximation, the electronic structure of an infinite silicon-carbide sheet, and nanoribbons and one-dimensional chains cut from it, is considered. Analytical expressions for band gaps, electron effective masses and characteristic velocities are derived. The effect of metal and dielectric substrates on the band characteristics is discussed.

“Antizeolite” borates are built with the positively charged porous [Ba12(BO3)6]6+ framework, hosting various guest anion groups. Resembling zeolitic structures, the porous borates ease with the con...

Cinnamate 4-hydroxylase (C4H; CYP73A) is a cytochrome P450 monooxygenase associated externally with the endoplasmic reticulum of plant cells. The enzyme uses NADPH-cytochrome P450 reductase as a donor of electrons and hydroxylates cinnamic acid to form 4-coumaric acid in phenylpropanoid metabolism. In order to better understand the structure and function of this unique class of plant P450 enzymes, we have characterized the enzyme C4H1 from lignifying tissues of sorghum (Sorghum bicolor), encoded by Sobic.002G126600 Here we report the 1.7 A resolution crystal structure of CYP73A33. The obtained structural information, along with the results of the steady-state kinetic analysis and the absorption spectroscopy titration, displays a high degree of similarity of the structural and functional features of C4H to those of other P450 proteins. Our data also suggest the presence of a putative allosteric substrate-binding site in a hydrophobic pocket on the enzyme surface. In addition, comparing the newly resolved structure with those of well-investigated cytochromes P450 from mammals and bacteria enabled us to identify those residues of critical functional importance and revealed a unique sequence signature that is potentially responsible for substrate specificity and catalytic selectivity of C4H.

Thin films of Dirac semimetal Cd3As2 about 100 nm thick made of single crystals of cadmium arsenide, prepared by direct fusion of the elements by vacuum–ampoule method, by vacuum–thermal sputtering/depostion have been studied. Temperature and magnetic field dependences of electrical resistance have been measured, which indicate the presence of a superconducting transition at a temperature from 0.2 to 0.6 K.

A subthreshold discharge excited by a microwave beam in air at pressures close to atmospheric is studied as a plasmachemical method of nitrogen oxide (NOx) production. It is shown that at the energy expenditure level (2–4) kW h/m3, it is possible to produce a nitrogen oxide concentration in pure air that exceeds the concentration in the initial gas by several orders of magnitude. At the same time, it is shown that it is possible to stop nitrogen oxide production almost completely by adding an admixture of methane (CH4) to the irradiated air, which makes the so-called self-non-self-sustained (SNSS) discharge much more promising for cleaning the gaseous exhausts from urban landfills from harmful admixtures (hydrogen sulfide, mercaptans, etc.).

The process of formation of cobalt silicides near the graphene-silicon carbide interface by intercalation of single-layer graphene grown on the 4H- and 6H-SiC(0001) polytypes with cobalt and silicon is studied. The experiments were carried out in situ in ultrahigh vacuum. The analysis of the samples is performed by high-energy-resolution photoelectron spectroscopy using synchrotron radiation, low-energy electron diffraction, and also Raman spectroscopy, atomic-force and kelvin-probe microscopies. The thicknesses of the deposited cobalt and silicon layers is varied to 2 nm, and the sample temperature, from room temperature to 1000°C. Co and Si atoms deposited on heated samples is found to penetrate under graphene and are localized between the buffer layer and the substrate, which leads to a transformation of the buffer layer into additional graphene layer. It is shown that the result of intercalation of the system with cobalt and silicon is the formation under two-layer graphene of a Co–Si solid solution and silicide CoSi coated by the surface Co3Si phase. It is shown that the thickness and the composition of the formed silicide films can be changed by varying the amount of the intercalated material and the order of their depositions.

The metallic ion components of the absorption energy of Ga and Cl atoms on C and Si faces of p- and n-SiC have been calculated in the framework of the Haldane–Anderson model. It is shown, first, that the ion contribution is higher than the metallic contribution in all cases under consideration. Second, the binding energy of Ga adatoms during adsorption on p-SiC is higher than that of Cl adatoms, while, in the case of adsorption on n-SiC, the opposite situation is observed. A simple ionic model of adsorption of a GaCl molecule on silicon carbide has been proposed. The comparison with the results of other authors demonstrates the acceptability of the proposed models.

The adsorption of barium atoms on C and Si faces of 3C-, 6H-, and 4H-SiC polytypes is examined using the Haldane–Anderson model. The charge transfer from a barium adatom to the substrate is analyzed with band and local states of the adsorption system taken into account. The ionic and metallic contributions to the adsorption energy are estimated. The surface molecule model is used to verify some of the results.

Understanding the interactions of organic donor and acceptor molecules in binary associates is crucial for design and control of their functions. Herein, we carried out a theoretical study on the properties of charge transfer complexes of 1,3,6-trinitro-9,10-phenanthrenequinone (PQ) with 23 aromatic π-electron donors. Density functional theory (DFT) was employed to obtain geometries, frontier orbital energy levels and amounts of charge transfer in the ground and first excited states. For the most effective donors, namely, dibenzotetrathiafulvalene, pentacene, tetrathiafulvalene, 5,10-dimethylphenazine, and tetramethyl-p-phenylenediamine, the amount of charge transfer in the ground state was shown to be 0.134−0.240 e−. Further, a novel charge transfer complex of PQ with anthracene was isolated in crystalline form and its molecular and crystal structure elucidated by single-crystal synchrotron X-ray diffraction.

Indium Selenide (InSe) is a remarkable two-dimensional quantum material whose characteristic properties include a bandgap in the near infrared region that increases with fewer layers. InSe is known to crystallize in either the β-, γ- or the e-phase. Of these three crystalline phases, only the β and γ exhibit a direct bandgap, which makes them suitable for optoelectronic applications. The β-phase is easily distinguished from the others by means of Transmission Electron Microscopy (TEM), whereas the γ- and e-phases appear very similar. We determine the crystalline phase present in these InSe specimens by systematic investigation with High Resolution TEM. We further assess the local electronic properties using Electron Energy-Loss Spectroscopy (EELS) by mapping relevant features in the spectra. Finally, we deploy Machine Learning techniques for a model-independent subtraction of the Zero Loss Peak, making it possible to identify features in the ultra-low-loss region of the EELS spectra.

The core@shell nanostructures were obtained in the process of transformation of ferrocene Fe(C5H5)2 at high pressure (HP) of 8 GPa and high temperature (HT) of 900 °C with an isothermal exposure time t varying from 10 to 10000 s. At t > 300 s, the iron carbide o-Fe7C3 nanoparticles with an orthorhombic crystal structure (sp.gr. Pnma) can be created, which are dispersed in highly defective carbon matrix. After opening the high-pressure cell, a series of redox reactions occurs, leading to a formation of iron oxides on the surface of the iron carbide core. When the size of Fe7C3 nanoparticle is less than critical one the nanoparticle is fully oxidized, while in the larger particle an amorphous iron oxide shell is formed. A sequential increase in t initiates crystallization processes both in the iron carbide subsystem and in the carbon subsystem, resulting in the formation of core@shell Fe7C3/FexOy/C structures. Iron oxides with a cubic spinel-type structure (Fe3O4/γ-Fe2O3) appear in the shell. However, under oxygen reduction, part of magnetite can be transformed into wustite FeO. The magnetic properties of magnetite and wustite are radically different, and by varying the thickness of these layers, structures with the desired functional properties can be obtained.

Thin films of solid solutions based on the three-dimensional Dirac semimetal Cd3As2 with the addition of manganese are investigated. Cd3 –xMnxAs2 films (x = 0, 0.05, and 0.1) 50–70 nm in thickness are formed on a glassceramic substrate using vacuum-thermal deposition from cadmium arsenide ingots doped by Mn and fabricated by direct alloying elements by the vacuum-cell method. The temperature and magnetic-field dependences of the resistance are measured and the transport parameters of the films under study are determined. Positive magnetoresistance of the characteristic shape corresponding to the contribution of the weak antilocalization effect is observed for films with x = 0 and 0.05. The contribution from the weak localization effect is observed at a higher Mn content (x = 0.1). This change in the quantum correction type as applied to topological semimetals points to reconstruction of the band structure and transition from the Dirac semimetal state into a trivial semiconductor phase, which corresponds to the critical Mn content xc ~ 0.07 in this case.

—Molecular heterogeneity in seven human metastatic melanoma cells lines is revealed using a double immunofluorescent assay by flow cytometry. It is evaluated that quite a small population of cells (up to 10%) expressed only vimentin, the main marker of melanoma. Only epithelial cytokeratins expression is revealed in a significantly greater number of cells (from 25 to 50%). The dominant molecular phenotype (50–80% cells expressed both markers), the coexpression of vimentin and cytokeratins, is identified for the first time. The authors assume that the latter phenotype of melanoma cells may be a molecular marker of the tumor’s aggressiveness and metastatic potential.

The results of studies of the spontaneous photoluminescence and stimulated emission spectra of epitaxial n-InN layers with a concentration of free electrons of ~1019 cm–3 are reported. The layers are grown by molecular-beam epitaxy with the plasma activation of nitrogen on sapphire substrates with AlN and GaN buffer layers. It is found that, as the InN layers are grown under conditions with enrichment with nitrogen at a growth temperature elevated to 470°C close to the beginning of the decomposition of InN, the crystal quality of the layers is improved and the stimulated-emission threshold is lowered. As the conditions of growth change to conditions with enrichment with the metal, two emission bands separated by an energy of 100 meV are observed in the spontaneous-photoluminescence spectra of InN. For such layers, a substantial increase in the stimulated-emission threshold and, in some cases, the lack of a transition to stimulated emission are observed. In the study, an interpretation of the observed emission bands is given and some inferences as to their nature are made.

An urgent public health problem is the optimization of drug therapy in patients with chronic heart failure.A large number of works devoted to the treatment of chronic heart failure form the point of view that about the treatment of chronic heart failure «all is well known for a long time.» However, in real clinical practice, especially at the stage of primary health care, for various reasons, possible pitfalls, reefs and shallows are not taken into account, the underestimation of which can introduce certain difficulties and cause the treatment of patients with chronic heart failure to be ineffective.The review article examined a number of important aspects of the treatment of chronic heart failure, which, for various reasons, are underestimated in the supervision of patients. First of all, this refers to antagonists of mineralocorticoid receptors, in particular to spironolactone, and an inhibitor of If - channels of the sinus node ivabradine.The results of foreign and Russian studies, modern recommendations for the supervision of patients with chronic heart failure, indicate that the presence of spironolactone and ivabradine in the arsenal of a practical doctor allows optimizing drug therapy in patients with chronic heart failure and increasing its effectiveness.

X-ray crystallography, quantum chemical modeling, IR, and electron spectroscopy methods are used to establish the structure of N-hydroxyamide of 3-[3,3-dimethyl-1,2,3,4-tetrahydroisoquinolin-1-iden]-2-oxopropanoic acid (1) possessing antifungal activity. It is shown that compound 1 exists in the form of an enamino-ketone-hydroxamic isomer in both crystalline state and solutions. The total charges on the atoms of the tetrahydroisoquinoline fragment and the atoms of the substituent in position 1 in molecule 1 are +0.425 e and −0.425 e, respectively. The structural and spectroscopic characteristics can be used in the studies of similar compounds.

Using the method of measuring ohmic resistance of steel AISI 304 specimens, the time dependence of steel corrosion rate in the 0.1–2 M HCl solutions is determined under the conditions of free air access. In the 0.5 M HCl solution, the effect of thiourea and polyethylene polyamine inhibitors on the steel AISI 304 corrosion rate is studied. It is shown that the inhibitory effect of thiourea on the corrosion rate of AISI 304 steel depends on the time of steel exposure to the solution.

Mo nitrogenase (N2ase) utilizes a two-component protein system, the catalytic MoFe and its electron-transfer partner FeP, to reduce atmospheric dinitrogen (N2) to ammonia (NH3). The FeMo cofactor c...

The adsorption of atomic and molecular nitrogen and ammonia on silicon carbide is considered within two physically different (solid-state and quantum-chemical) approaches. In the solid-state approach, the Haldane–Anderson model is used for the density of states of the SiC 4H and 6H polytypes to demonstrate that the energy of binding to the substrate is 6 and 3 eV for N atoms and N2 molecule, respectively. In the quantum-chemical approach, the model of a surface diatomic molecule is used to find that the binding energy of atomic nitrogen is 6 and 4 eV for adsorption on the C- and Si-edges, respectively. It has been established that the charge transfer between an adsorbate and the substrate may be neglected in all the considered cases. It has been hypothesized that the dissociation of a molecule with the further passivation of its dangling sp3-orbitals with hydrogen atoms takes place for silicon carbide as in the case of ammonia adsorption on Si(100).