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Properties of supported Pt-containing granular (Pt/Ce0.75Zr0.25O2–δ) and monolithic structured (Pt/Ce0.75Zr0.25O2–δ /η-Al2O3 /FeCrAl) catalysts were studied in the methanol decomposition to syngas for feeding solid oxide fuel cells (SOFC). The application of the monolithic structured catalyst in the methanol decomposition reaction was shown to be promising. The addition of a small oxygen amount to the initial mixture was found to prevent the formation of carbon, thus enhancing the stability of catalyst operation. The proposed monolithic structured catalyst 0.15 wt.% Pt/8 wt.% Ce0.75Zr0.25O2–δ /6 wt.% η-Al2O3 /FeCrAl at atmospheric pressure, temperature of ca. 400 °C, feed rate of the reaction mixture 5.6 L/(gcat·h) and volumetric ratio СН3ОН/air = 1 can provide the complete conversion of methanol to syngas with the total content of H2 and СО of ca. 64 vol.% and the syngas output of ca. 6.7 L(Н2 + СО)/(gcat· h).

Layered Ni-Mg-Al hydroxides with (Ni + Mg)/Al = 2.5 differing in Mg/Ni ratios and related oxide systems have been synthesized and characterized. Ni-Mg-Al hydroxides were prepared by the coprecipitation method. It was found that the samples dried at 110 °C were layered Ni-Mg-Al hydroxides with a hydrotalcite-type structure. After the heat treatment at 600 °C, the formation of Ni-Mg-Al-mixed oxides with a specific nanostructure, an intermediate between a NaCl and spinel structure, took place. According to XRD data, it had the unit cell parameter a = 4.174–4.181 Å, and a crystallite size of 4.0 nm. The specific surface area of the Ni-Mg-Al samples dried at 110 °C was 45–54 m2/g, and that of those calcined at 600 °C was 156.1–209.1 m2/g. In agreement with HRTEM data, in all the synthesized nickel catalysts reduced at 700 °C (H2), particle size was mainly distributed between 15–20 nm. The catalyst activity of LDH-derived Ni-Mg-Al catalysts in ammonia decomposition was studied in a fixed-bed flow-type reactor at an atmospheric pressure within the temperature range 500–700 °C. The synthesized catalysts overcame existing analogues in catalytic performance. At a process temperature of 500 °C, the Ni2Mg3Al2-HT catalyst showed that the H2 productivity was 23.8 mmol/(gcat·min), exceeding the respective value of nickel catalysts reported in the literature.

A spectrometer has been developed at the beamline EXAFS-D station of the Kurchatov synchrotron-radiation source at the Kurchatov Institute National Research Center for the precision determination of relative variations in the lattice parameters of single crystals. The spectrometer allows measurements of small (up to 3 × 10−7) relative variations in the lattice parameter, which may be caused by stoichiometry violation or external actions, e.g., inverse piezoelectric effect. The method of X-ray diffraction in a geometry that is close to backscattering at angles as large as 179.5° is implemented in the spectrometer. Using a synchrotron source, it is possible to select the radiation wavelength for tuning the spectrometer to the near-backscattering diffraction geometry. The equipment of the spectrometer allows simultaneous monitoring of the lattice-parameter variation and mapping of the elemental composition over the crystal surface.

The role of diffuse pollution of water bodies in the formation of water quality in them is characterized. Some features of diffuse pollution, which are of importance for managing the process of their reduction, are identified. The main lines of the activity for managing the reduction of diffuse pollution are determined and characterized, including basin programming, regional planning, ecological direction of sectoral improvement, governmental stimulation. The problem of incorporation of measures for reducing diffuse pollution in the River Basin Management Plan and the application of Water Quality Objectives for regulating diffuse pollution is considered. Proposals are given for improvement the application of the principle of best available technologies for reducing diffuse pollution.

The analysis of the current state of issues related to scour of the bottom and foundations of hydraulic structures under the influence of jets from ship propulsor is presented. The possibility of using an alternative approach to ensuring safety during the operation of thin quay walls by immersing the sheet pile to a greater depth with the creation of a reserve for possible scour has been revealed.

A thermodynamic analysis is performed of the patterns of steam conversion of natural gas at temperatures of 300–600°C, pressures of 0.1–4 MPa and H2O : C molar ratios of 0.8‒1.2. Under these conditions, the reaction product is methane–hydrogen mixtures with hydrogen concentrations of 10–30 vol %. A rise in temperature, molar ratio Н2О : С, and a decrease in pressure contribute to an increase in the concentration of hydrogen in the reaction products. The thermodynamic boundaries of the process with no carbonization of the catalyst are determined. Experiments are performed to obtain methane–hydrogen mixtures from methane with an output concentration of 15–35 vol % hydrogen on industrial Ni-CrOx-Al2O3 catalyst at 325–425°C, a H2O : C molar ratio of 0.8–1.0, and atmospheric pressure. It is shown that under these conditions, the process proceeds without the formation of carbon on the catalyst.

The processes of hydrogen production from various types of fossil and renewable fuels are energy-intensive multi-route chemical reactions, and for their efficient implementation it is necessary to use selective and high-performance catalysts that combine high activity, thermal conductivity, and corrosion and thermal resistance. A general strategy for the design of catalytic systems for hydrogen production is outlined; it consists in the use of composite catalysts of the “metal nanoparticles/active oxide nanoparticles/structural oxide component/structured metal support” type; an approach for their directed synthesis is described. The structured metal support provides efficient heat removal or supply for exo- or endothermic reactions, possesses good hydrodynamic characteristics, and facilitates scale transition. The structural oxide component (aluminum oxide) provides thermal and corrosion resistance and a high specific surface area of the catalytic coating, as well as performing a protective function for the metal support. The active oxide component (mainly cerium–zirconium oxides) increases resistance to carbonization due to oxygen mobility and maintains a high dispersion of the active component due to its strong metal–support interaction. Metal nanoparticles 1–2 nm in size are involved in the activation of substrate molecules. FeCrAl alloy wire meshes, formed into cylindrical blocks of specified sizes, to be used as a heat-conducting substrate. By controlled annealing with the formation of a micron α-Al2O3 layer and subsequent deposition of a η-Al2O3 layer according to the Bayer method (through aluminum hydroxide), a structural layer of η-Al2O3 with a “breathing” needle morphology was deposited onto the FeCrAl alloy surface; then the catalytic active component was deposited onto this layer by impregnation and/or deposition. The efficiency of the proposed strategy is shown for Rh/Ce0.75Zr0.25O2 – δ–η-Al2O3/FeCrAl catalysts for methane tri-reforming and Cu–CeO2 – δ/η-Al2O3/FeCrAl catalysts for dimethoxymethane steam reforming.

A mixture of iron carbides and fullerene C60 formed by electric arc synthesis has been hydroxylated by adding OH groups to the fullerene surface, which made it possible, according to the EXAFS data, to obtain almost pure fullerenol Fe@C60(OH)30. Powder samples of the fullerenol and the product obtained after its dehydroxylation have been examined using Mossbauer spectroscopy. The Mossbauer spectra have been processed under the assumption of superposition of three partial doublets of spectral lines. It is established that two doublets due to Fe3+ dominate in the fullerenol spectrum. For the reduced fullerene Fe@C60 sample, two doublets are due to Fe3+ and the Fe2+ doublet dominates. Thus, attachment of OH groups from the outer side of the fullerene carbon frame increases the oxidation state of iron, which shows that the iron atom is located inside the frame.

The author develop the conceptual control system model to ensure the sustainable projected promising packet radio network HF-band operating. It is proposed to implement the control functions at the Element Management System level on the basis of automated radio centers, and to implement the Network Management System level management functions on the basis of a dedicated server. Such a management approach allows you to build a hierarchical centralized radio network management system architecture. We can observe a simulation modeling for the developed algorithms of the selected radio network control functions. The paper presents the simulation results, namely probabilistic-temporal characteristics of the processes reliability, routing and functioning under attacks.

Results of experimental investigations of large-diameter shells subjected to regular waves in the construction period are presented. Factors responsible for a loss of stability of the backfill material are identified.

The nuclear magnetic resonance (NMR)-relaxation characteristics of protons in pure aqueous and buffer solutions of highly hydroxylated endofullerenols with paramagnetic gadolinium ions at ambient temperature have been studied. These systems were thoroughly characterized by SANS and examined by NMR at various resonance frequencies: f = 2 kHz–500 MHz. In all the cases, we have discovered much higher longitudinal and transversal relaxation rates as compared to the reference salt solutions with Gd+3 ions in the same range of concentrations (0.1–10.0 mM/l). We suppose that this effect is due to the fact that the objects studied reveal well-manifested abilities to the self-assembly in acidic conditions. As a result, the transversal relaxation rate (1/T2) increases greatly, and also the longitudinal relaxation rate (1/T1) demonstrates a broad maximum at resonant frequencies f ~ 20–100 MHz that are determined by the time of fullerenol diffusive rotations. The relaxation rates, which increase linearly with fullerenol content (0.1–10.0 mM/l), testify the stable assembly. The studied features of fullerenol assembly and its strong influence on the proton relaxation make it possible to suppose good prospects of these metal–carbon structures for biomedical applications, in particular, as contrast agents in MRI.

The state of the art in the protection of the bottom near and the foundations of hydraulic structures from scour caused by marine propulsors is analyzed. The need to formulate recommendations on determining the parameters of the scouring action and engineering measures to protect the bottom against scour is identified.

The interaction between a γ-Al2O3 surface and vapors of H2O and D2O is studied via IR spectroscopy. It is shown that surface hydroxyl groups of ОН and OD form at temperatures as low as 100–200°С. It is estimated that these hydroxyl groups exhibit Bronsted acidity, and their interaction with NH3 leads to the formation of NH $$_{4}^{ + }$$ ions.

The article studies and analyzes the experience of using digital information technologies in Russian metallurgy enterprises, therefore the object of the research is metallurgical company as a complex socio-economic system. Digital technologies are considered as a key tool in the control system of all processes and streams in the enterprise. The basis is the model for the formation of the full stream of creating product value as a combination of material, information and operational streams. The mechanism for creating value-creating streams using digital technologies is considered as a set of interconnected elements, the nature of the relationships between which allows to realize the purpose of the management system - to make the company effective and efficient, which determines the scientific novelty of the presented research.

The analysis of the current state of issues related to the erosion of the bottom and construction of foundations of port hydraulic structures under the influence of hydraulic jets from ship engines is presented. The most common structures made of sheet piles and methods of fixing the soil on the bottom in front of berths and the causes of erosion are considered. Standard construction solutions and problems associated with their implementation are analyzed. The possibility of using an alternative approach to ensuring safety in the operation of thin mooring walls by sinking the sheet pile to a greater depth with the creation of a reserve for possible erosion is revealed. A container ship with dimensions corresponding to the Arctic shuttles that are used in ports and waters of the Northern Sea Route has been accepted as a settlement ship. Methods for calculating the erosion flow rate for soils composing the bottom of the water area and methods for determining the depth of erosion from the action of ship engines with different power are proposed. As part of the study, two options were developed and compared: the first is a standard one with the bottom fixed by building structures, the second option involves a deeper immersion of sheet piles to the depth of possible erosion. The recommended sequence of calculations of the area of bottom erosion at the berth and the depth of erosion from the action of ship engines is proposed. A container ship with a DWT 35000 is accepted as the settlement ship. The cost-effectiveness of the thin sheet pile wall option with the proposed erosion protection in the form of deeper pile immersion exceeds traditional methods by at least 30%.

This article presents measurements of the piezoelectric modulus d 11 of a single crystal of lanthanum gallium silicate (LGS, La3Ga5SiO14). The piezoelectric modulus was measured by X-ray diffraction at angles close to backscattering. Experiments in such schemes are very sensitive to relative changes in the lattice constant in crystals caused by external influences (constant or alternating electric field, mechanical load, temperature change etc.). The development opportunity of the technique is shown, its applicability is evaluated and results of measurement of the LGS single-crystal piezo modulus by the method of diffraction of synchrotron radiation at angles near π are discussed.

The possibility of using arctic low-sulfur diesel fuel for the production of syngas suitable for solid-oxide fuel cells (SOFSs) in a single stage via the prereforming reaction over Ni-MgO structured catalysts based on a highly porous cellular foam material (HPCFM) made of nickel is demonstrated. Catalysts with mass compositions (wt %) 10.7NiO–10MgO/HPCFM and 20NiO–10MgO/HPCFM are prepared, and their properties in the prereforming of arctic diesel fuel at 550°C are studied. The microstructure of the coating of these catalysts is studied via transmission electron microscopy (TEM) before and after the reaction. The resistance of these prereforming catalysts to carbonization is revealed to be the key factor influencing their stability under operation. The kinetic parameters of this reaction are determined. The obtained results could be helpful in creating power generation units based on fuel cells operating on arctic diesel fuel under the conditions of the Far North.

The results of experimental investigations of seafloor scour near the foundations of gravity platforms under the frontal impact of regular waves and currents are presented. The effect of current velocities on the location of the scour zone relative to the structure is determined.

The possibility of using low-sulfur Arctic diesel fuel for production of synthesis gas appropriate for solid oxide fuel cells was demonstrated. That was one-stage pre-reforming reaction in the presence of structured Ni-MgO catalysts based on high-porous foam cellulated (HPFC) material. Catalysts 10.7 wt %NiO-10 wt %MgO/HPFC, 20 wt %NiO-10 wt %MgO/HPFC were prepared, their properties characterized in Arctic diesel fuel pre-reforming at 550 °C. TEM technique was used for studying the microstructure of the catalyst coat before and after the reaction. It was revealed that the key factor affecting the operational stability of the pre-reforming catalysts was their resistance to coking. Kinetic parameters of the reaction were determined. The results obtained can be helpful for constructing energy units based on fuel cells fed by Arctic diesel fuel in the Arctic regions.

The results of experimental study and mathematical modeling of a fuel processor for the production of pure hydrogen from diesel fuel with a productivity of 600–700 g (H2)/h, consisting of an adiabatic reactor for diesel fuel pre-reforming followed by steam conversion of pre-reforming products in a catalytic Pd–Ag membrane reactor for hydrogen extraction are presented. The membrane reactor consists of 32 membrane modules arranged in 8 sections of 4 modules each. A mathematical model has been developed and two schemes of layout of the modules in the membrane reactor have been simulated. One scheme involves the cross-flow distribution of flue gas and fuel gas reformate to individual modules and leads to overheating of the input modules and cooling of the output modules. The other scheme with the cocurrent distribution of streams, along both the reactant path and the flue gas path, is preferable from the viewpoint of the temperature uniformity of different modules within a section. On the basis of the data obtained, an estimated calculation of the parameters of a power generation unit with a battery of low-temperature fuel cells has been made. For the example considered, the thermal efficiency of the fuel processor is 87%. With an efficiency of the fuel cell battery of 42%, the electrical efficiency of the fuel cell power unit will be 36%.

The gas-phase carbonylation reaction of dimethoxymethane (DMM) to methyl methoxyacetate on different solid acids was studied. It was established that this reaction was accompanied by the occurrence of a side reaction of DMM disproportionation into dimethyl ether and methyl formate. It was shown that the activity of solid acids in both of the reactions depends on the strength of Bronsted acid sites according to an equation like the Bronsted–Evans–Polanyi–Semenov correlations.

The performance of a СuO–ZnO/γ-Al2O3 catalyst for the reactions of methanol, dimethyl ether (DME) and dimethoxymethane (DMM) steam reforming (SR) to hydrogen-rich gas was studied. The catalyst was found to be active and selective for methanol and DMM SR producing hydrogen-rich gas with low content of CO (

The performance of a multipurpose synchrotron spectrometer is diversified by installing additional equipment for the studies of diffraction in the Debye–Scherrer geometry. The design of X-ray optics and technical characteristics of the spectrometer are described. Diffraction patterns for polycrystals detected in both the forward and backward hemispheres are illustrated.

The performance of the Kurchatov Institute’s multiporpose synchrotron spectrometer is diversified by adding the equipment for the X-ray fluorescent element analysis. The X-ray optical focusing system of the spectrometer is described. The analysis results for the copper, lead, and gold-nanofilm samples are reported.

Systematic studies were performed on low-temperature steam conversion or low-temperature steam reforming (LTSR) of propane in an excess of methane on a Ni-based catalyst. The LTSR of the methane–propane mixture is a two-stage process involving the irreversible steam conversion of propane into carbon dioxide and hydrogen and reversible methanation of carbon dioxide. Above ~250°C, the methanation of carbon dioxide is quasi-equilibrium. The rate of propane conversion during the LTSR of the methane–propane mixture is first-order based on propane; its activation energy is ~120 kJ/mol and is almost independent of the methane, carbon dioxide, hydrogen, and steam concentrations. This very simple macrokinetic scheme allows us to correctly describe the experimental data and predict the temperature and flow rate of the mixture at which complete conversion of propane is achieved.

The improved X-ray optical scheme, the system of registration, and the measurement procedure of the multifunctional synchrotron radiation spectrometer in the dispersive EXAFS mode are described. The results of the spectrometer energy resolution measurements are given. The advantages and disadvantages of traditional and dispersive EXAFS spectrometers are analyzed. Examples of EXAFS spectra measured in the dispersive mode are given.

The pre-reforming of diesel fuel combined with subsequent steam reforming of pre-reforming products integrated with membrane separation of hydrogen is the most promising way of obtaining pure hydrogen for fuel cells. Here, we consider the first part of this problem-diesel fuel pre-reforming. The following commercial nickel-containing catalysts have been tested in the pre-reforming reaction: NIAP-18 (Ni, 15 wt %; CaO, 8 wt %; Al2O3, 74.4 wt %), NIAP-12-05 (Ni, 48 wt %; Cr2O3, 27 wt %), NIAP-07-01 (NiO, 36 wt %), NIAP-07-05 (NiO, 38 wt %; Cr2O3, 12 wt %). A number of new pre-reforming catalysts based on manganese and cobalt compounds have also been examined. The tests have been carried out at pressures of 1, 6, and 15 atm, temperatures of 470–560°C, and gas hourly space velocities of 6000–12000 h−1. The experiments have demonstrated that the nickel-containing catalysts afford a near-equilibrium product composition, while the reaction over the catalysts based on manganese and cobalt compounds yields a nonequilibrium product composition. A mathematical model has been developed for diesel fuel pre-reforming in an adiabatic reactor with a fixed catalytic bed. Model parameters ranging from process kinetics to heat and mass transfer coefficients have been estimated. The results of modeling have been compared to experimental data available from the literature. The potential of the mathematical model has been illustrated by performing calculations for adiabatic reactors with various output capacities.

Artificial, grounded ice islands built by controlled flooding of the sea ice surface with sea water have been used for exploratory drilling in the Arctic offshore. Islands fabricated from ice are becoming more prevalent as offshore oil speculation in the Arctic gains more interest. Ice has been a strategic building material in the Arctic for the construction of roads, airstrips, housing, and, in the last few decades, as temporary drilling platforms to explore for oil. This article describes various methods of artificial ice building, the advantages and disadvantages of using man-made ice islands for exploratory drilling.

The need to study the problem of seabed local scour near offshore platforms has arisen in Russian Federation in connection with the activation of oil and gas production from fields located in coastal areas of seas (in accordance with the Energy Strategy for the period up to 2030, approved by the Government of the Russian Federation on November 13, 2009, No1715-p). Operation of offshore platforms is characterized by a number of features: shallow water areas; severe storm conditions; large transverse dimensions of structures that cause waves diffraction; the variety of used structure forms; the way of platform mounting on the seabed. During platform operation in the shallow waters, its basement soil is under an intense impact of sea waves, currents, as well as jets from engine of coming and berthing ships. The structure disturbs the natural wave flow. Near the platform, flow velocity increases, there are vortexes breakaway from platform corner edges. Scour holes appear and progress near platform foundation. Their location and measure depend on the parameters of external impacts, on the water depth, on the shape and dimensions of the foundation block.

Different types of methods needed to determinate risk of natural hazards on the field for different types of hazards. Avalanche and rockfall act the same, get acceleration from gravity depend on slope. It mostly often that they both possible in mountain region around the earth. But behavior of this processes is different and consequences are also different. To predict rockfalls and avalanches we have to create method which can be compared with reality. Compare model versus reality possible in areas with many years of observations. So we can use thisa model to simulate behavior of rockfalls and avalanches in not studied areas.

Drilling operations conducted from artificial islands are both feasible and economical in shallow waters. Accumulated experience in the construction and operation of artificial gravel islands are analysed. Capital protection of island’ slopes against the action of ice and waves are considered.

Correction to the article “Assessment of State of Backfill Material in Large-Diameter Shells Subjected to the Effect of Wind Waves,” by N. D. Belyaev, V. V. Lebedev, I. S. Nudner, K. K. Semenov, and D. I. Shchemelinin, Vol. 53, No. 3, September 2019, pp. 300 – 306

An X-ray optical system is developed for a station intended for the investigation of samples with high locality under extreme conditions, i.e., high pressures and high or low temperatures. One- and two-dimensional refractive lenses and polycapillary lenses are discussed as examples of focusing systems.

An X-ray optical system is developed for a station intended for the investigation samples with high locality under extreme conditions, i.e., high pressures and high or low temperatures Various mirrors of total external reflection are considered as options for focusing elements in the system.

Scouring, caused by waves, currents and races of ship propellers, has been a subject of theoretical investigations, physical modeling in hydraulic laboratories and full-scale experiments in several countries. The results reported on these tests usually recommend formulas and diagrams to determine water velocities that can be used to estimate the risk of scouring and design the required protection measures. The results of the physical modeling of interaction of long tsunami-type waves with an offshore gravity platform are presented in this article. The reaction of seabed soil to wave impact at the platform foundation has been studied and the obtained results have been analyzed. Conclusions about changes in the seabed profile, density of the top layers of the seabed soil and their influence on the platform stability have been made.

A unique combination of methods (TPD of O2, thermogravimetry, isotopic heteroexchange of oxygen in different modes) was used to carry out detailed studies of oxygen mobility and reactivity in mixed praseodymium nickelates-cobaltites (PrNi1 − x Co x O3 + δ) and their composites with doped cerium dioxide (Ce0.9Y0.1O2 − δ) as promising cathodic materials stable towards the effect of CO2 in the intermediate-temperature region. It is shown that in the case of composites of PrNi1 − x Co x O3+δ-Ce0.9Y0.1O2 − δ synthesized using the Pechini method and ultrasonic treatment, stabilization of the disordered cubic perovskite phase due to redistribution of cations between the phases provides high oxygen mobility. Preliminary results on tests of cathodic materials of this type supported on planar NiO/YSZ anodes (H.C. Starck) with a thin layer of YSZ electrolyte and a buffer Ce0.9Y0.1O2 − δ layer showed that power density of up to 0.4 W/cm2 was reached in the region of medium (600–700°C) temperatures, which was close to typical values for fuel cells of this type with cathodes based on strontium-doped perovskites and their composites with electrolytes.