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Orthoniobates of rare-earth elements are a promising group of materials attractive for the design of nanocomposite hydrogen separation membranes owing to a perspective type of proton conductivity, good mechanical properties, and high stability in H2O- and CO2-containing atmospheres. In general, the promising method involves the synthesis of nanocomposites with transition metals (Cu, Ni, and Cu-Ni alloys) and their oxides with high electronic conductivity. For the first time, lanthanum orthoniobates and nanocomposites with NiCu and NiCo nanoparticles were synthesized using alcohol solutions of salts of the corresponding metals by the solvothermal method in a flow reactor in a supercritical isopropanol medium. This method made it possible to obtain single-phase La0.99Ca0.01NbO4–δ oxide. The introduction of doping titanium cations did not allow obtaining a single-phase La0.99Ca0.01Nb0.98Ti0.02O4–δ sample, as impurities in lanthanum methaniobate and La2Ti2O7 were found. Calcined powders and gastight pellets of orthoniobates and nanocomposites were characterized by X-ray diffraction analysis as well as scanning and transmission electron microscopy. Transport characteristics were investigated by the Van der Pauw technique, varying measurement temperatures in a wet H2 atmosphere. The oxygen mobility was estimated by the oxygen isotope heteroexchange with C18O2.

The purpose of this work is to provide theoretical framework and experimental supporting evidence for a crucial role of structural transitions in the ensemble of defects at the meso-level (microshears and microcracks), as one of the mechanisms of plastic strain localization in metals under high-rate loading. The investigation of the sample response to dynamic loading was carried out on the split Hopkinson pressure bar and in a series of target penetration tests. To identify the characteristic stages of strain localization, the thermodynamics of the deformation process was investigated "in-situ" by recording the temperature fields using a high-speed infrared camera CEDIP Silver 450M. The temperature measured in the localization zone does not confirm the generally accepted concept of the strain localization mechanism as the mechanism governed by a thermoplastic instability. The samples stored after the experiment were subjected to microstructural analysis, using an optical interferometer-profilometer and a scanning electron microscope. The structural analysis revealed a correlated behavior of the ensemble of defects, which can be classified as a structural transition providing strain localization. The data of experimental studies, the examination of the structure of deformed samples, as well as the data of numerical modeling taking into account the kinetics of accumulation of microdefects in the material suggest that one of the mechanisms of plastic strain localization at high loading rates is associated with the jump-like processes in the defect structure of a material.

Climate change dramatically impacts the structure of energy business by adding renewables. In traditional energy networks, the balance between the demand for- and the offer of- power is managed by increasing the amount of commodity or by shedding loads. Customer-centered grid brings new paradigm about changing the economic behavior of small- and medium- scaled energy users instead of varying the amounts of commodity that is called flexibility. Flexible cooperative behavior of many actors participating in liberalized intraday market reduces pollutants because it optimizes renewable energy. However, it has implications on power markets in terms of prices and has technology implications nation-wide. This article discusses a generational change that moves decision making from few control rooms to the democratic neighborhood of the web. The objective is to present a changed socio-economic context and attract the attention of researcher to new challenges. The main result is a dynamic equilibrium that exists between the reward offered by the utilities to their customers and the advantage obtained by the utilities from such a flexible behavior. The article main conclusion is on the role of new market product called demand-side flexibility in the transformation of power markets towards ecological sustainability. Key words: Demand-side flexibility, energy market, intraday trading.

An experimental and theoretical study of fracture mechanisms of the AMg6 alloy at different structural levels was carried out under consecutive dynamic and fatigue tests associated with conventional catastrophic events of aircraft engine components (fan blades) due to the foreign object damage and the life-time decrease in the presence of a corrosive environment. The AMg6 alloy samples were preloaded dynamically using the split Hopkinson-Kolsky bar at the strain rates ∼103 s−1 and then subjected to the VHCF test up to 108–109 cycles at the Shimadzu USF-2000 resonance testing machine (the load frequency is 20 kHz) with the cooling by abundant compressed-air and salt fog (3% NaCl). The scaling analysis of fracture surface roughness was conducted to characterize quantitatively specific areas associated with the stages of damage-failure transition in the presence of the corrosion.

The phenomenon of plastic strain localization in alloys under dynamic loading was experimentally studied on a Hopkinson–Kolsky bar and during target penetration tests. The temperature fields generated during deformation were studied in situ using a CEDIP Silver 450M high-speed infrared camera with the aim to identify the characteristic stages of localized shear. The temperature field distribution obtained at different time allowed us to trace the evolution of plastic strain localization. Microstructural analysis of the post-test samples was carried out using an optical interferometer-profilometer and electron microscopes. The structural analysis provided evidence for the correlated behavior of the ensemble of defects, which can be classified as a structural transition responsible for the strain localization. The results of experimental studies, the study of the deformed sample structure, as well as the data of numerical simulation made with consideration for the evolution of microdefects in the material, suggest that one of the mechanisms of plastic strain localization in alloys under high-speed loading is caused by jump-wise processes in the defective structure of materials.

Widespread renewable energy alters infrastructures and business by changing a way to balance between the demand and the offer. In customer-centered model, flexible economic behavior of small-scaled energy actors mitigates variability and uncertainty in flows of power and energy. Flexible cooperative behavior of many intraday market participants has a potential to reduce uncertainty in renewable energy flows. However, owners of small-scale renewable energy plants play limited market role. This chapter presents changed socio-economic and technology contexts and attracts attention to new challenges. New ICT enabler activates role of small-scale renewable energy actors by complementing their physical energy by structured information about the capacity and flexibility. In new market scenario, unpredictability of renewable energy is reduced by adding knowledge and exploiting better flexible behavior. Main conclusion is about using the information about flexibility to activate small-scale actors on real-time markets while improving ecological sustainability.

Experimental studies on the response of samples to dynamic loading were performed using a split Hopkinson-Kolsky bar and in a series of perforation tests. In-situ investigations of the thermodynamics of deformation processes made it possible to identify the characteristic deformation localization stages. Temperature fields were recorded with a high-speed infrared camera CEDIP Silver 450M, and strain localization in the samples was evaluated with a strain noninvasive measurement system StrainMaster. Temperature measurements made in the localization zone did not support a generally accepted concept that the strain localization mechanism is the mechanism governed by thermoplastic instability. The microstructural analysis of the samples stored after the experiment was carried out using an optical interferometer-profilometer and a scanning electron microscope. The analysis revealed the correlated behavior of the ensemble of defects, which can be classified as a structural transition providing strain localization. The data of experimental studies, the examination of the structure of deformed samples, as well as the data of numerical modeling performed with consideration of the kinetics of accumulation of microdefects in the material suggest that one of the mechanisms of plastic strain localization at high loading rates is associated with the jump-like processes in the defect structure of the material.

The transition to generation-led Smart Grid has determined a need to materialize the Demand-side Flexibility. In a changed market scenario, small-scale users will be enabled to sell the ancillary balancing services as a particular good that complements amounts of the energy-containing commodity. In Transactive Energy Control scenario, the market operations should be accompanied by the tools for analytical accounting of both parts of the Control as a Service, the energy amounts (a) and the flexible ramps (b). It asks for new measurement and control instruments, especially because of security implications. This work describes a prototype built in the context of an EU-funded project SUCCESS.