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Rheological measurements are used in the food industry to determine physical characteristics of raw materials, as well as semi-finished and finished products. We aimed to study the effects of ingredients and homogenization parameters on the rheological properties of mayonnaise prepared with pumpkin and rice oils, as well as various honeys. Mayonnaise samples were prepared with non-traditional ingredients, namely cold-pressed pumpkin seed oil, refined rice oil, and four varieties of honey (acacia, linden, forest, and spring). The samples were made in the traditional way on an Ultra Turrax T25 IKA homogenizer (3500–24 000 rpm). The rheological properties of honey and mayonnaise were determined on a Brookfield rotational viscometer. Forest honey had the highest viscosity, while linden honey had the lowest viscosity, compared to the other honeys. The sample of mayonnaise with forest honey had the highest effective viscosity (3.427 Pa·s) and consistency (101.26 Pa·sn). The use of whey powder provided mayonnaise with the most optimal rheological parameters. Of all carbohydrates, inulin HD had the best effect on the consistency of mayonnaise, with effective viscosity of 2.801 ± 0.001 Pa·s and a flow index of 0.2630 ± 0.0020. Disaccharides provided mayonnaise with higher viscosity and consistency than monosaccharides. Mayonnaise with fresh egg yolk had higher viscosity (2.656 ± 0.002 Pa·s) and consistency (65.640 ± 0.004 Pa·s) than the samples with other egg products. The rheological characteristics of mayonnaise were also determined by the homogenization time and rotor speed. Increasing the time from 2 to 4 min at 10 000 rpm raised the emulsion’s viscosity and consistency from 6.253 to 8.736 Pa·s and from 77.42 to 134.24 Pa·sn, respectively, as well as reduced the flow index from 0.2628 to 0.1995. The rotor speed of 10 000–12 000 rpm was optimal for mayonnaise with pumpkin and rice oils and honey. The studied samples of mayonnaise with pumpkin and rice oils, as well as honey, belong to non-Newtonian systems and pseudoplastic fluids. The empirical flow curves can be adequately described by the Herschel-Bulkley model. Our results can significantly increase the efficiency of mayonnaise production, improve its quality, and reduce production costs.

Anode-supported solid oxide fuel cells with thin electrolytes show good electrochemical performance. In this work, 4-μm-thick YSZ electrolyte with 2-μm-thick GDC barrier layer is deposited onto the substrates by reactive magnetron sputtering. It is shown that high power density can be obtained for 5 × 5 cm2 cells under planar stacks conditions with stainless steel current collectors. Electrochemical investigations are performed in the temperature range of 600-800°C. High power density of 0.29, 0.83, 1.4 W cm-2 is achieved at a voltage 0.7 V and 600, 700, and 800°C, respectively.

The aerosol deposition (AD) method is a technique for the formation of thin and thick, gas-tight, and porous layers by deposition of microscopic powder particles. In the present work, the AD was used to deposit thin-film electrolyte and protective buffer layers for planar anode-supported solid oxide fuel cells (SOFCs). The high quality of deposited layers was confirmed by scanning electron microscopy, as well as electrochemical measurements, including the measurements of current-voltage characteristics and impedance spectroscopy. At working temperature of 800°C the anode-supported cell with bi-layered electrolyte deposited by AD demonstrated the open-circuit voltage of more than 1.04 V, as well as specific power of more than 780 mW/cm2. The difficulties, advantages, and peculiarities associated with the formation of thin-film electrolyte and buffer layers of SOFCs by the AD method have been discussed.

Combined technique and setup have been created that combines capabilities of electrochemical methods, as well as high-temperature Raman spectroscopy (RS) at Osipyan Institute of Solid State Physics RAS. In order to study the processes in the electrochemically active zone, a special geometry of samples was developed on basis of optically transparent single crystal membranes of an anionic conductor with a toroidal shape counter-electrode. With the use of this combined technique and special geometry, studies of the kinetics of reduction of nickel in composite SOFC anodes were carried out. The influence of the composition of fuel on Raman spectra obtained from the internal interface in the current load mode was also investigated, and the correlations with the cell voltage were studied. RS is also used to study the structure of single-crystal samples of anionic conductors, including at SOFCs operating temperature. The new combined technique was used to study other components: sealing glasses for SOFCs and optical glasses.

Steam reforming is a highly endothermic process of hydrogen or synthesis gas production from methane or other hydrocarbon fuels. Metals from group VIII of the Periodic table are catalysts for steam reforming; nickel is the most commonly used among them. Platinoid catalysts: rhodium, ruthenium and palladium are more active, but less frequently used due to their high cost. Nickel catalysts have proven their effectiveness due to the simplicity of their production, stability and chemical activity [1]. It is known that the heat required for the endothermic process of steam reforming can be provided by an electrochemical reaction in a stack of high-temperature solid oxide fuel cells [2,3]. In the case of internal reforming, the process of steam reforming of methane proceeds directly at the anode of a solid oxide fuel cell (SOFC) due to the high operating temperature and the presence of nickel in the composition [4,5]. The advantage of internal reforming is not only thermal, but also chemical integration of reforming agent and generator – the water vapor produced during the SOFC anodic electrochemical reaction can be used for reforming without the need for anode recycling organization. Also, the endothermic effect of steam reforming can be used to control the temperature of the stack. As it was shown in work [6] feeding of the mixture containing 30% of methane into the electrolyte-supported SOFC stack to the input leads to 22% of methane observed at the output. Thus, based on the literature data, we cannot expect a high conversion rate in the process of internal methane reforming. Therefore, studies of the internal methane conversion process were carried out on an experimental short stack of two 100x100 mm electrolyte-supported SOFCs. A whole series of experiments were carried out on H2+CH4+H2O mixtures with different sets of conditions – an increase in the ratio and consumption of methane, and then a decrease in temperature. The ranges of methane consumption and other key parameters of the experiment were based on the results of the analysis of available literature data on the experimental study of the kinetics of methane steam conversion on cermet SOFC anodes. Prior to the experiments, discussions were mainly caused by the probable carbon deposition at the anodes and the associated rapid performance degradation, the capabilities of the anodes for internal conversion were upper estimated according to the fuel consumption of SOFCs, so it was assumed that, at worst case, the conversion provides only its internal consumption needs. The results of experiments at an operating temperature of 850°C showed that the kinetics of internal conversion was largely underestimated. The assembly of two SOFCs converts methane up to concentrations not exceeding the calculated equilibrium ones, up to the maximum available flow rate on the equipment used – 187 ml/min – even without current passing. This fuel flow rate is capable of providing a current of up to 53 A, while the rated operating current of these SOFCs is about 20 A, up to 30 A on methane-rich fuel. This means, that the conversion capabilities of SOFC even in the absence of current are at least twice higher than their own needs. The current further stimulates the conversion by generating additional steam. In order to discover the limits of conversion capabilities, the temperature was lowered to 750°C. The result of the conversion at maximum flow rate proceeding up to equilibrium values was repeated. Thus, in the course of the experiments, it was not possible to obtain methane concentrations in the exhaust gas that significantly exceed the equilibrium ones. This result turned out to be extremely unexpected and undoubtedly positive, since it demonstrates an extremely high potential of internal conversion and opens the way to a sharp decrease in the requirements for the degree of conversion of fuel supplied to SOFC, abandonment of a bulky fuel processor, reduction of costs for SOFC cooling and, thereby, an increase in efficiency and reducing the mass and dimensions of SOFC power plants. This work was carried out with financial support from the Russian Scientific Foundation, grant no. 17-79-30071. References 1. Tokyo Gas Co. Ltd., Japanese Patent No. JP 06-243881 (1994) 2. A.H. Fakeeha et al. J. King Saud Univ., Vol. 7, Eng. Sci. (Special Issue), pp. 171-189 3. S. H. Clarke et al. Catalysis Today 38 (1997) 41 l-423 4. A.L. Dicks Journal of Power Sources 71 (1998) 111–122 5. В.А. Собянин Ж. Рос. хим. об-ва им. Д.И. Менделеева (2003) XLVII №6 с. 62-70 6. Kupecki, K. Motylinski, J. Milewski Energy Procedia 105 (2017) 1700–1705

A comparative analysis of the features of the formation, morphology, and electrochemical activity of composite anodes of solid oxide fuel cells was performed using nanosized particles of NiO and Ce0.8Gd0.2O2 – δ. The direct introduction of NiO nanoparticles into cermet composition leads to technological problems during screen printing of electrode layers associated with the oxidation of organic components of electrode pastes with oxygen, which is desorbed from the NiO surface. Such problems can be solved by pre-heating treatment of NiO. However, this treatment and subsequent firing of the anodes leads to an increase in the particle size to submicron. An increase in electrochemical activity can be achieved by impregnating the anodes with the formation of nanosized catalytically active particles on their surface.

We investigated the impact of a series of hole transport layer (HTL) materials such as Poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), NiOx, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine (PTAA), and polytriarylamine (PTA) on photostability of thin films and solar cells based on MAPbI3, Cs0.15FA0.85PbI3, Cs0.1MA0.15FA0.75PbI3, Cs0.1MA0.15FA0.75Pb(Br0.15I0.85)3, and Cs0.15FA0.85Pb(Br0.15I0.85)3 complex lead halides. Mixed halide perovskites showed reduced photostability in comparison with similar iodide-only compositions. In particular, we observed light-induced recrystallization of all perovskite films except MAPbI3 with the strongest effects revealed for Br-containing systems. Moreover, halide and β FAPbI3 phase segregations were also observed mostly in mixed-halide systems. Interestingly, coating perovskite films with the PCBM layer spectacularly suppressed light-induced growth of crystalline domains as well as segregation of Br-rich and I-rich phases or β FAPbI3. We strongly believe that all three effects are promoted by the light-induced formation of surface defects, which are healed by adjacent PCBM coating. While comparing different hole-transport materials, we found that NiOx and PEDOT:PSS are the least suitable HTLs because of their interfacial (photo)chemical interactions with perovskite absorbers. On the contrary, polyarylamine-type HTLs PTA and PTAA form rather stable interfaces, which makes them the best candidates for durable p-i-n perovskite solar cells. Indeed, multilayered ITO/PTA(A)/MAPbI3/PCBM stacks revealed no aging effects within 1000 h of continuous light soaking and delivered stable and high power conversion efficiencies in solar cells. The obtained results suggest that using polyarylamine-type HTLs and simple single-phase perovskite compositions pave a way for designing stable and efficient perovskite solar cells.

Three-layered ceramic membranes based on stabilized zirconia for planar solid-oxide fuel cell (SOFC) are prepared by the tape casting method. The outer layers containing 94 mol % ZrO2–6 mol % Sc2O3 provide the enhanced mechanical stability; the inner layer has the composition of 89 mol % ZrO2–10 mol % Sc2O3–1 mol % Y2O3 which has the highest anionic conductivity in the series of solid solutions ZrO2–Y2O3–Sc2O3. Studying the mechanical characteristics shows that the ultimate strength (bending strength) of these membranes much exceeds the value typical of single-layered samples. The anionic conductivity of three-layered ceramics is studied by the impedance spectroscopy in the frequency range from 1Hz to 1 MHz. Membrane-electrode assemblies for SOFCs are fabricated and their electrochemical properties are studied under the conditions of fuel cell operation.

In order to evaluate applicability of Ce0.6 –хLa0.4PrхO2 – δ (x = 0–0.2) fluorites for protective interlayers and electrode components for intermediate-temperature solid oxide fuel cells (SOFCs), their thermal expansion, chemical interaction with solid electrolyte material, tolerance towards reduction and electrochemical behavior were studied. The incorporation of praseodymium into Ce0.6La0.4O2 – δ was found to increase unit cell parameters and thermal expansion coefficients, from (13.2 ± 0.3) × 10–6 to (18.5 ± 0.8) × 10–6 К–1 at intermediate temperatures. Increasing total concentration of rare-earth cations in the fluorite-like cerium dioxide structure also correlates with decreasing thermodynamic stability under both oxidizing and reducing conditions. As a result, high-temperature chemical interaction between the Pr-doped materials and lanthanum gallate-based solid electrolyte becomes more intensive with respect to Ce0.6La0.4O2 – δ, whilst reduction of Pr-containing solid solution may leads to segregation of a secondary phase with the C-type structure. The combination of these factors deteriorates compatibility of the interlayers with other SOFC components. Consequently, the overpotentials of PrBaFe1.2Ni0.8O6 – δ cathodes in the electrochemical cells with (La0.9Sr0.1)0.98Ga0.8Mg0.2O3 – δ solid electrolyte were –42 and –143 mV in O2 atmosphere at the current density –58 mA/cm2 and 1073 K when the interlayers of Ce0.6La0.4O2 – δ or Ce0.5La0.4Pr0.1O2 – δ were used, respectively.

The work is devoted to investigation of the electrochemical behavior of (Fe,Ni)Ox-based composite anodes in the hydrogen- and methane-containing fuel. Among the studied composites, the optimum electrochemical characteristics were observed for anodes with Fe : Ni ratio approaching 2. In particular, for the electrodes with initial composition 50 vol % Fe0.67Ni0.33Oх–50 vol % Zr0.85Y0.15O1.93 the anode overpotential equals 20–30 mV at a current density of 50–80 mA/cm2 in 10% Н2–Ar–H2O at relatively low temperatures (873–923 K). Increasing current leads to further activation, presumably due to a partial oxidation of metallic particles located at the anode surface. However, the microstructure degradation of the anode layers still represents a significant problem for their utilization. Testing of the electrocatalytic activity of the anodes fabricated from Ni, Zr0.83Sc0.17O1.92 (ScSZ) and Ce0.9Gd0.1 O2 – δ (GDC) revealed a high activity toward catalytic partial methane oxidation with the subsequent electrochemical oxidation of the conversion products, as well as formation of carbonaceous deposits at the nickel surface. The methane conversion degree on Ni-anode comes to 60–90% and decreases with time and on cooling. The doping of nickel oxide with iron lowers the conversion degree and promotes the carbon poisoning, supposedly, because of the lowering of the anodic current density resulting from the worsening of the electrochemical activity.

Herein, we reveal for the first time a comprehensive mechanism of poorly investigated electrochemical decomposition of CH3NH3PbI3 using a set of microscopy techniques (optical, AFM, PL) and ToF-SIM...

This work is a study of the effect of co-doping (ZrO2)0.9(Sc2O3)0.1 solid solution with yttria and/or ceria on the phase composition, local structure and transport properties of the crystals. The solid solution crystals were grown using directional melt crystallization in cold crucible. We show that ceria co-doping of the crystals does not stabilize the high-temperature cubic phase in the entire crystal bulk, unlike yttria co-doping. Ceria co-doping of the (ZrO2)0.9(Sc2O3)0.1 crystals increases their conductivity, whereas the addition of 1 mol.% yttria tangibly reduces the conductivity. Equimolar co-doping of the (ZrO2)0.9(Sc2O3)0.1 crystals with ceria and yttria changes the conductivity but slightly. Optical spectroscopy of the local structure of the crystals identified different types of optical centers. We found that the fraction of the trivalent cations having a vacancy in the first coordination sphere in the ceria co-doped crystals is smaller compared with that in the yttria co-doped crystals. Keywords: Single crystals, Solid oxide fuel cell, Solid solutions, Ionic conducting materials, ZrO2-Sc2O3-CeO2-Y2O3

Protective Ni-based coatings for stainless steel current collectors of the planar solid oxide fuel cells (SOFCs) were developed and tested during 21,000 h in contact with lanthanum-strontium manganite cathode material. The compositional and microstructural alterations due to interdiffusion between Ni coating, La0.8Sr0.2MnO3 electrode and commercial Crofer 22 APU steel after long-term testing under the SOFC cathodic conditions, were studied. The results of micro-Raman spectroscopy and electron microscopy analyses showed a dominant role of Mn and Fe diffusion into the protective coating, leading to the formation of NiFe2O4 and MnFe2O4. Although Mn deficiency in the manganite cathode may decrease electrical conductivity, its impact on the overall contact resistance is insignificant. The Ni-based coatings were found to decrease area-specific interfacial resistivity down to 3–4 mOhm × cm2 for, at least, 21,000 h (>2.5 years) at 1123 K, atmospheric oxygen pressure and current density of 0.5 A/cm2.

In this work, we systematically explored the photochemical stability of MAPbI3 interfaces with five different charge transport layers (CTLs): substituted naphthalene (NDI) and perylene (PDI) diimides, fullerene derivatives PC61BM and PC71BM, and widely used hole transport material spiro-OMeTAD. While studying these model systems, we revealed several important interfacial degradation pathways. First, we demonstrated that diimides (both NDI and PDI) strongly accelerate the photodegradation of MAPbI3 since they specifically interact with PbI2 formed as one of the perovskite degradation products. Fullerene derivatives, in turn, absorb another decomposition product, methylammonium iodide (MAI), which also results in accelerated ageing of the perovskite films deposited atop fullerene-based CTLs. However, both fullerene derivatives and spiro-OMeTAD have excellent encapsulation properties and strongly suppress photodecomposition of MAPbI3, when the perovskite films are placed underneath. Unfortunately, the observed impressive perovskite bulk phase stabilization using PC61BM, PC71BM and spiro-OMeTAD coatings does not improve the operation lifetime of photovoltaic cells due to interfacial degradation processes. TOF-SIMS analysis has revealed accumulation of the perovskite decomposition products (presumably CH3I) in the spiro-OMeTAD layer as well as a noticeable degradation at the interface with the electron transport tin dioxide layer. The obtained results emphasize the major challenge in the development of perovskite solar cells with long operation lifetime related to poor stability of the functional perovskite/CTL interfaces.

This report presented by the Institute for Statistical Studies and Economics of Knowledge of the National Research University Higher School of Economics (HSE ISSEK) is dedicated to the statistical measurement of the creative economy of Moscow. This publication gives a first ever classification of Moscow’s creative industries – sectors of the economy where the major part of gross value added is generated out of creative activity and intellectual property rights management, and provides a description of approaches to calculating key indicators of their economic and territorial development. Original assessments of creative employment and foreign trade of creative goods on the basis of official data sources, as well as infographic profiles of selected creative industries, are provided. The report will be of practical interest to representatives of public authorities, managers and employees of companies, educational institutions, research institutes, experts and all involved in the creative economy agenda.

In order to increase efficiency of metal-supported solid oxide fuel cells (SOFCs) and electrolysis cells (SOECs) and to lower their fabrication and operation temperatures, development of novel methods for the functional layers deposition is of primary importance. In this work, the composite anodes of metal-supported solid oxide cells (MS-SOCs), made of Ni and 10 mol.% scandia and 1 mol.% yttria co-stabilized zirconia (10Sc1YSZ), were deposited by the aerosol deposition (AD) onto high relief porous metal substrates. This step was followed by magnetron sputtering (MSP) of thin 8 mol.% yttria-stabilized zirconia (8YSZ) solid electrolyte. Vacuum co-sintering of the half-cells at 1100 °C resulted in the formation of well-bonded nanostructured anodes and gas-tight electrolyte membranes. The area-specific ohmic resistance of the half-cell in dry hydrogen was 0.23 Ohm·cm2 at 577 °C.

In this work we report a study of (ZrO2)1−x−y(Sc2O3)x(СeO2)y solid solution crystals (x = 0.08–0.10; y = 0.005–0.015) grown by skull melting technique. The crystal structure of the material was studied using X-ray diffraction, Raman spectroscopy and impedance spectroscopy. The study showed that optically homogeneous and transparent crystals cannot be grown from the melt in the experimental composition range. For overall stabilizing oxide concentrations of above 10 mol% the crystals contained a cubic phase and a rhombohedral one, whereas at concentrations of lower than 10 mol% a cubic and a tetragonal phases coexisted. Ceria introduction into the (ZrO2)1−x(Sc2O3)x system increases its high-temperature ionic conductivity. The highest ionic conductivity was observed in 0.5 mol% ceria containing crystals.

The comparative analysis of electrotransport characteristics and structure of ceramic and single crystal solid electrolytes with the (ZrO2)0.89(Sc2O3)0.10(Y2O3)0.01 composition is carried out before and after their life tests. It is shown that before the life tests, the specific conductivities of single-crystal and ceramic materials virtually coincide. During the 3000 h life tests, the specific ionic conductivity decreases for both single crystal and ceramic samples down to about 0.1 S cm–1 but the degradation of conductivity in single crystal proceeds more slowly as compared with the ceramic material. The reason for degradation of electrotransport characteristics in the single crystal is associated with the transition of its bulk structure from the t′′ phase to a phase with the higher degree of tetragonality, whereas in the ceramic material, in addition to the latter process, a rhombohedral phase appears presumably along grain boundaries.

The oxygen nonstoichiometry and electrical conductivity of fluorite-type solid solutions Ce0.6‒xLa0.4Pr x O2–δ (x = 0.1–0.2) were studied in the oxygen partial pressure range 10–19–0.35 atm at 1023–1223 K. It was confirmed that the Pr4+/3+ and Ce4+/3+ redox pairs, which determine the concentration of p- and n-type electron charge carriers, play the dominant roles under oxidizing and reducing conditions, respectively. The conductivity vs. charge carrier concentration dependencies in these conditions are almost linear. Increasing praseodymium content leads to a substantially higher hole conductivity and an expanded range of the oxygen nonstoichiometry variations at high oxygen partial pressures. Under reducing conditions when praseodymium cations become trivalent opposite trends are observed on doping.

The Fe–Ni–O system designed for producing bimetal-containing composite anodes of solid oxide fuel cells (SOFCs) was studied. The solubility of nickel in the structure of spinel (Fe,Ni)3O4 ± δ at atmospheric oxygen pressure is ~1/3. Moderate reduction at 1023 K and p(O2) ≈ 10–20 atm leads to partial decomposition of spinels, forming an electron-conducting phase (Fe,Ni)1–yO and submicron bimetallic Fe–Ni particles on the oxide surface, which have potentially high catalytic activity. The electron conductivity has a thermally activated character and increases substantially during the reduction. In the anode conditions of SOFCs, the electric conductivity reaches 30–100 S/cm, while the thermal expansion coefficients are ~12 × 10–6 K–1, which ensures compatibility with solid electrolytes. At the same time, significant volume changes during the redox cycling (up to ~1% on the linear scale) necessitate the introduction of additional components such as yttria-stabilized zirconia (YSZ). The polarization resistance of the model composite anode of reduced Fe2NiO4 ± δ and YSZ deposited on the YSZ solid electrolyte membrane was ~1.8 Ohm cm2 at 923 K in a 4% H2–Ar–H2O atmosphere.

The combined experimental approach for in-situ Raman spectroscopy of the inner “anode|electrolyte” interfaces in solid oxide fuel cells under current load was examined in a case study centered on the behavior of gadolinia-doped ceria (GDC) interlayers between cermet anodes and stabilized zirconia membrane. The Raman spectra of ceria at 850 °C were found sensitive enough with respect to the variations of anodic current and fuel gas mixture composition, which induce oxygen nonstoichiometry changes in GDC. Linear dependence of the Raman peak area on the open-circuit voltage makes it possible to estimate local overpotentials at the GDC interlayer|electrolyte interface under current load. The calculated local overpotentials exhibit a Tafel-like dependence on the current density, and are essentially independent on the hydrogen and water vapor partial pressures within the limits of experimental uncertainties. The relevant rate-determining mechanism may be associated with ion transfer via the GDC|zirconia interface, whilst the contributions of exchange-related processes involving gaseous phase are less significant in this interfacial zone.

Mechanical strength and microstructure of the anode supports are among the most critical factors affecting the long-term stability and performance of the intermediate-temperature solid oxide fuel cells (IT-SOFCs). In this work, the anode supports made of Ni/NiO and 10 mol.% Sc2O3 and 1 mol.% Y2O3 co-stabilized zirconia (10Sc1YSZ) were fabricated by tape casting, followed by sintering and screen-printing of the anode functional layer of 10 mol.% Gd2O3 doped ceria (10GDC) and NiO. Then two dense solid-electrolyte layers, 8 mol.% Y2O3 stabilized zirconia (8YSZ) and 10GDC, were deposited by the reactive pulsed dual magnetron sputtering. Mechanical properties of as-sintered and reduced anode supports were estimated employing three-point bending technique. The power density of model anode-supported SOFCs, where mechanical stability of the support was kept after complete reduction in hydrogen, achieved 0.3 W/cm2 at 800°C and 0.6 V under air/hydrogen gradient.

A stack based on planar solid oxide fuel cells (SOFCs) is an assembly of ceramic plates - membrane-electrode assemblies (MEA) and metal current collectors, which play the role of the distribution of gas mixtures over the electrode area, as well as current collection. In order to organize the high-quality current collection it’s necessary to provide a reliable electrical contact between the MEA’s electrodes and contact surfaces of the current collectors. Electrical contact between MEAs’ anode electrode and the collector is achieved by pressing the contact nickel meshes. Metal-based conductive adhesives are also used to reduce the contact resistance at the anode electrode. Despite this in order to ensure contact between the MEA’s cathode electrode and the collector this approach is not applicable due to the rapid oxidation of contact meshes in air atmosphere at high temperatures. In turn, contact pastes based on conductive ceramics do not have such a drawback and make it possible to ensure reliable contact under the conditions of the SOFC cathode chamber. Materials for the contact adhesive for the SOFC cathode chamber must be chemically and thermomechanically compatible with the materials of the SOFC cathode and bipolar plate along with high electrical conductivity. These requirements are met by materials based on lanthanum strontium manganite oxide (LSM) materials, which are widely used as cathode materials for SOFCs. It should be noted that the contact adhesive must also correspond to the limitations of technological processes of SOFC stack manufacturing. SOFC stacks are sealed with glass in a temperature range of 930-950°C, so it’s necessary to use a material that forms a conductive contact at temperatures not higher than 950°C, which is significantly lower than typical sintering temperatures of LSM-based cathode. The synthesis of single-phase highly dispersed powders with the composition of La0.8Sr0.2MnO3±δ (LSM) and (La0.8Sr0.2)0.97MnO3±δ (LSM-d) was carried out by the glycine-nitrate method. After synthesis some of the obtained materials were ball-milled in ethanol using 5 mm ceramic milling bodies at a speed of 600 rpm for 300 and 600 min. A mixture of polyvinyl butyral, toluene, and butanol was used as the basis for the contact paste. Tests of the electrical conductive properties of contact pastes were carried out in air in temperature range of 600-950°C. Samples were kept for 2 hours before cooling at the maximum temperature. Figure shows the results of resistivity measurements: the dashed lines represent the values obtained when the sample was cooled. The maximum values of the resistivity at a temperature of 850°C were obtained for contact adhesive samples based on non-activated stoichiometric (LSM) and A-deficient (LSM-d) powders. Low electrical conductivity can be associated with weak intergranular contact due to the strong agglomeration of the material after synthesis. Grinding for 300 minutes results in a noticeable reduction in the resistivity of the contact adhesive (LSM-300). Change in resistivity after holding at maximum temperature, as well as the change in the slope of the temperature dependence of the resistivity of the adhesive based on LSM-300 indicates the sintering of the contact adhesive powder into a ceramic compact, which is confirmed by SEM results. In turn, holding at a temperature of 950°C of contact adhesive based on LSM-600 (600 min grinding pre-activated) powder does not lead to its sintering. Grinding of the initially single-phase LSM powder results in the appearance of additional reflections in the XRD-spectrum corresponding to the Sr(OH)2 and MnCO3 phases. An increase in the grinding time leads to an increase in the proportion of impurity phases that prevent the contact adhesive from sintering at temperatures Thus, the best results were shown by a contact adhesive based on stoichiometric LSM powder, pre-activated by grinding for 300 minutes. Holding at a temperature of 950°C leads to sintering of LSM-300 powder into ceramics, which makes it possible to form a reliable electrical contact under the conditions of the SOFC cathode chamber. We have proposed a method for the manufacture and deposition of a contact cathode composition based on La0.8Sr0.2MnO3±δ. It is shown that the initial powders obtained by the glycine-nitrate method according to the Pechini modification are preliminary prepared. The optimal grinding parameters have been determined. The sintering modes of the contact paste are selected, which are consistent with those for the sealing glass. An experimental SOFC assembly was made using a contact cathode paste. It is shown that the electrochemical characteristics of individual MEAs correspond to the declared ones and the specific power reaches 0.25W/cm2. This work was carried out with financial support from the Russian Scientific Foundation, grant no. 17-79-30071. Figure 1

This work shows the correlation between the crystal structure, phase composition and transport characteristics of ZrO2 based solid electrolytes depending on the concentration of the stabilizing impurity Y2O3. The crystals ZrO2 stabilized with yttrium oxide in a wide range of compositions (from 2 to 15 mol% Y2O3) were studied. The phase composition, twin structure, and conductivity of the crystals we determined for all concentrations by X-ray diffraction, transmission electron microscopy, Raman and impedance spectroscopy. The ionic conductivity of the crystals was changed nonmonotonic, with increasing Y2O3 concentration. The existence of two maxima of ionic conductivity at temperatures 800–900 °C for compositions ZrO2-3.2 mol% Y2O3 and ZrO2-8 mol% Y2O3 was established. We show that twin boundaries do not trigger any additional ionic conductivity acceleration mechanism in ZrO2-Y2O3 crystals. The highest conductivity is observed in ZrO2-(8–10) mol% Y2O3 crystals containing the t″ phase in which the oxygen atoms are shifted from the high symmetry positions that are typical for the cubic phase.

The results on optimizing the procedure of preparation of the electrode system within membrane–electrode assemblies (MEA) of solid-oxide fuel cells (SOFC) by joint sintering of electrodes at the enhanced temperature close to that of anode sintering are presented. The MEA are prepared based on membranes of the anionic conductor HionicTM (Fuel Cell Materials, USA); the cathode is formed based on cation–deficient lanthanum-strontium manganite (La0.8Sr0.2)0.95MnO3 with addition of activated carbon for optimizing its microstructure; the anode is formed on the basis of cermet NiO/10Sc1CeSZ (89 mol % ZrO2, 10 mol % Sc2O3, 1 mol % CeO2). The results of electrochemical testing of model MEA are also shown.

In this paper a detailed study of the (ZrO2)1-x(Y2O3)x (x = 0.025 – 0.15), (ZrO2)1-x(Sc2O3)x (x = 0.06 – 0.11) and (ZrO2)1-x-y(Sc2O3)x(Y2O3)y (x = 0.07 – 0.11; y = 0.01 – 0.04) solid solution crystals grown by skull melting technique is presented. The structure, phase composition, and ion conductivity of the obtained crystals were investigated by X-ray diffraction, transmission electron microscopy, Raman scattering spectroscopy, and impedance spectroscopy. Maximum conductivity as (ZrO2)1-x(Y2O3)x and (ZrO2)1-x(Sc2O3)x solid solution crystals is observed for the compositions containing 10 mol% stabilizing oxide, and the conductivity of 10ScSZ is ~3 times higher than for 10YSZ. Experiments on crystal growth (ZrO2)1-x-y(Sc2O3)x(Y2O3)y solid solutions showed that uniform, transparent crystals 7Sc3YSZ, 7Sc4YSZ, 8Sc2YSZ, 8Sc3YSZ, 9Sc2YSZ, 9Sc3YSZ, 10Sc1YSZ and 10Sc2YSZ are single phase crystal containing t’’ phase. It is established that a necessary condition of melt growth of (ZrO2)1-x-y(Sc2O3)x(Y2O3)y single-phase crystals is the total concentration of the stabilizing oxides from 10 to 12 mol%. The addition of Y2O3 affects the (ZrO2)1-x-y(Sc2O3)x(Y2O3)y solid solution conductivity different ways and depends on the Sc2O3 content in the starting composition. The effects of structure, phase composition, concentration and type of stabilizing oxides on the electrical characteristics of obtained crystals are discussed. This article is protected by copyright. All rights reserved.

The interrelationship between the structure, phase composition, and transport characteristics of solid electrolytes based on ZrO2 has been studied as dependent on the content of stabilizing Y2O3 additive. It is established that twin boundaries do not lead to the appearance of additional mechanism of ionic conductivity acceleration in ZrO2–Y2O3 crystals. The maximum conductivity has been observed in ZrO2–(8–10) mol % Y2O3 crystals containing a t” phase, in which oxygen atoms are displaced from high-symmetry positions characteristic of the cubic phase.

For the first time crystals of the (ZrO 2 ) 1− x − y (Sc 2 O 3 ) x (Y 2 O 3 ) y solid solutions ( x =0.08–0.11; y =0.01–0.02) have been grown by directional melt crystallization. We have determined the range of melt compositions for which growth from the melt produces of the (ZrO 2 ) 1 − x − y (Sc 2 O 3 ) x (Y 2 O 3 ) y solid solution single crystals. The single-phase optically transparent single crystals following composition were grown: (ZrO 2 ) 0.9 (Sc 2 O 3 ) 0.08 (Y 2 O 3 ) 0.02 ; (ZrO 2 ) 0.89 (Sc 2 O 3 ) 0.09 (Y 2 O 3 ) 0.02 ; (ZrO 2 ) 0.89 (Sc 2 O 3 ) 0.10 (Y 2 O 3 ) 0.01 ; (ZrO 2 ) 0.88 (Sc 2 O 3 ) 0.10 (Y 2 O 3 ) 0.02 . Comprehensive study of the crystal structure by using XRD, transmission electron microscopy, and Raman spectroscopy revealed that the all single crystals, which is identified by XRD data as cubic one, in fact have t″ tetragonal structure, which forms by small displacement of oxygen ions along the c -axis. Data on the phase stability of the crystals during mechanical crushing were obtained. The electrical conductivity was measured as a function of temperature by electrochemical impedance spectroscopy. It is established that (ZrO 2 ) 0.89 (Sc 2 O 3 ) 0.10 (Y 2 O 3 ) 0.01 crystals have the highest conductivity (0.168 S/cm at 1173 K).

High-resolution transmission and scanning electron microscopy of the solid oxide fuel cell (SOFC) anodes made of Ni and yttria-stabilized zirconia (YSZ), revealed a substantial microstructural reconstruction induced by the anodic current. These microstructural alterations, primarily the growth of NiO inclusions at the Ni | YSZ interface, the resultant orientation relationship between the NiO and YSZ grains, and Ni grain fragmentation on subsequent reduction, provide a straightforward evidence for the so-called oxygen spillover mechanism of the anodic reaction.

The task of clustering of a set of objects is treated as the graph partitioning problem. The normalized cut criterion is used for a weighted graph partitioning and the approach is applied in two implemented algorithms. The results of testing the method for the journal citation network clustering are presented.

The article proposes a model for the complex analysis of formant surface structures in the process of understanding the deep content of units with complex semantics. In the study of the representation of morphological actants in the situation of inputting concomitant overtones of meaning at the vocabulary level, an integrated approach is used, which combines the theory of priming and the basic concepts of noematic analysis within the framework of philological phenomenological hermeneutics. Priming in the study correlates with predictive strategies as ²action patterns² in the distribution of hierarchically structured deep meaning. The article presents the results of the analysis of the experiment on the verbalization of connotative morphological components at the level of lexical input within the framework of explication of meaning shades using the example of German and Dutch units of complicated semantics. This approach contributes to the establishment of regularities for the implementation of a clearly defined Root-Priming, where the prerequisites of basic morphemes are targeted in non-transparent, unintelligible conditions. Analysis of the experimental data on spelling and morphological priming showed that simple units that have identical initial graphic or phonetic constructions and are used in cases of nomination of situations of neo-crisis will have a further priming effect on them that does not depend on the state of the variable segments. The constitutional implementation of priming is characterized by the re-implementation of phonograph components. Each priming includes processes reflecting the intentional activation of the value of a complicated unit and free association

The study provides rationale for meta-theoretical interpretation of a special type of a literary text – the one based on ultimate reflexion. The analysis rests on “camp prose” works characterized by a significant degree of abstraction on the part of the subject of narration and the possibility of contaminating the objective reality phenomena and the ones of personal reflexive reality within the framework of an “objective” observer description. The authors specify the meta-language of the first level abstraction and the peculiarities of constructing the analyzed type of text as a certain acting scheme for both the literary text producer and the recipient. The proposed scheme incorporates a peculiar cognitive experience (featuring creativity, abstraction, intuition and reflexivity) and a new phenomenological reflexion that imply a new way of realizing different types of experience within the scope of reflexive reality. The texts based on ultimate reflexion are defined as verbal-psycho-emotive entities that can trigger a certain state of consciousness in the process of reading and objectify different sense overtones implied by the author.

The authors analyze major features of complex multidisciplinary analysis models of the recipient’s perceptual capacity related to desobjectifying contextually determined transdisciplinary borrowing of newly emerging components within a semantic hierarchy. Critical analysis and comparison are applied to some alternative approaches in linguistic studies of transdisciplinary terminologization. There is a role revealed, which belongs to the cognitive-perceptual aspect in the respective knowledge field. The comprehensive phenomenon of component transgression within the meaning hierarchy is viewed from different angles: metaphoric and metonymic explication, and from the stance of conceptual integration of mental spaces and grammatical constructions of implicit meaning generation. The semantic foundations of the frame & semantic model of the borrowing theory serve a prototype of a comprehensive analytical model relevant not only in Linguistics, yet in other humanities (Literature, Psychology, Sociology). The comprehensive method of bottom-up analysis in studying explication of contextually determined overtones (forced reinterpretation of terms and terminoids) implies desobjectification of the semantic hierarchy at several levels. The analysis suggests that standard linguistic mechanisms can be employed through deautomation in the said cognitive modeling function. Reactivating a prototypical mental image within a new reflexive space is viewed as the most effective way of explicating the respective components.

Bilayered substrates for anode-supported solid oxide fuel cells (SOFCs), made of NiO and 10 mol.% Sc2O3 and 1 mol.% Y2O3 co-stabilized zirconia (10Sc1YSZ), were produced employing the tape casting technique. The optimization of the pore former (rice starch) content in the starting suspension and thermal treatment conditions provide necessary porosity, simultaneously maintaining sufficiently high mechanical strength of the composite measured by the three-point bending method. Bilayered gas-tight solid electrolyte films of 8 mol.% Y2O3 stabilized zirconia and 10 mol.% Gd2O3 doped ceria (8YSZ/10GDC) were deposited by magnetron sputtering, followed by annealing at 1200 °C. The area-specific power density of a model SOFC achieved 1.8, 1.4, and 0.9 W/cm2 at 800, 750, and 700 °C, respectively.

We have studied the influence of the yttrium oxide (Y2O3) dopant (1 and 2 mol %) on the phase composition, structure, and electrical properties of ZrO2–9 mol % Sc2O3 solid solution. Stabilization of ZrO2 jointly with 9 mol % Sc2O3 and 2 mol % Y2O3 is shown to allow the acquisition of high phase stability transparent homogeneous crystals with a cubic structure. Their mechanical grinding is established to cause no change in the phase composition of these crystals, whereas the powders retain the initial fluorine structure. The powders preserved the original structure of the fluorite crystals. All the probed crystals reveal high microhardness and low fracture toughness. Increasing the Y2O3 concentration in the crystals led to a reduction of the maximum loads on the indenter, which the sample withstood without cracking. As is shown, the specific conductivity exhibits nonmonotonic behavior depending on the Y2O3 concentration in the crystals. Increasing the Y2O3 content to 2 mol % in the solid electrolyte reduces the conductivity of the crystals in the entire temperature range that is attributed to a decrease in the carrier mobility due to the increasing ion radius of the stabilizing ion.

In recent decades, the attention of researchers and policymakers has turned to state-owned enterprises (SOEs), in particular the role they play in science, technology and innovation and the methods they use to implement innovation strategies. In this paper, we look at Russian state-owned companies and their development plans, as well as the management tools they employ to forecast and prioritize technologies. Although most Russian SOEs rarely implement corporate foresight and technology roadmapping, certain successful cases are presented and discussed in the paper. Based on these case studies, we suggest a common structure of a technology roadmap that is suitable for SOEs.