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Composite electroactive coatings (CEACs) are prepared on the basis of polyaniline (PANI) and manganese compounds (MnOx) by potentiodynamic electrodeposition on activated graphite foil using aniline sulfate solutions in 1 M H2SO4. Manganese ions are incorporated into the CEACs in several ways. The electrochemical behavior of prepared CEACs is fundamentally similar to that of pure PANI in acidic aqueous solutions. However, in the presence of incorporated manganese oxide compounds, the electrochemical capacitance nearly doubles at high current loads (up to 2.0 mA cm–2), while the stability during continuous cycling improves. X-ray photoelectron spectroscopy studies of the manganese oxide compounds incorporated into CEACs reveal their amorphous nature and that manganese atoms are present in CEACs in several oxidation states.

The article is devoted to the use of unmanned aerial vehicle for geothermal waters exploitation monitoring. Development of a geothermal reservoir usually requires a system of wells, pipelines and pumping equipment and control of such a system is quite complicated. In this regard, use of unmanned aerial vehicle is relevant. Two test unmanned aerial vehicle based infrared surveys have been conducted at the Khankala field (Chechen Republic) with the Khankala geothermal plant operating at different regimes: during the first survey – with, and the second – without reinjection of used geothermal fluid. Unmanned aerial vehicle Geoscan 201 equipped with digital (Sony DSX-RX1) and thermal imaging (Thermoframe-MX-TTX) cameras was used. Besides different images of the geothermal plant obtained by the surveys, 13 thermal anomalies have been identified. Analysis of the shape and temperature facilitated determination of their different sources: fire, heating systems, etc., which was confirmed by a ground reconnaissance. Results of the study demonstrate a high potential of unmanned aerial vehicle based thermal imagery use for environmental and technological monitoring of geothermal fields under operation.

Synopsis Climate change can directly and indirectly affect species distribution. Warming may allow for invasive species, such as apple snails, to migrate to higher latitudes where temperatures are more conducive to their survival and invasion success. Higher temperatures and lower pH ranges have been previously documented to affect the form and function of calcium carbonate shells, which serve many functions, including protection from predators and thermoregulation. This study aimed to quantify differences in the morphology and mechanical properties of invasive apple snail, Pomacea maculata, shells after altering temperature and pH. We mechanically tested shells among three five-week treatments: control, higher temperature, and lower pH. Ultimate Strength increased in shells that were exposed to higher temperatures, but Young’s Modulus and Peak Load did not differ among control, temperature, and pH treatments. Apple snails in higher temperature tanks increased their shell length over the five-week trials. Although snail morphometrics did not differ between sexes, male shells exhibited a higher Peak Load, Young’s Modulus, and Ultimate Strength compared to female shells. Our findings are consistent with previous gastropod studies, in that a lower pH is associated with a decrease in shell size, and higher temperatures yield larger snail shells with a higher ultimate strength. Peak Load did not significantly differ among treatments, which suggests that the cross-sectional area is relatively important when considering this species mechanical performance today and in future climates. Due to the intense nutritional and calcium demands of egg production, female snails may be more susceptible to weakened shells due to low pH environments caused by climate change.

To solve problems of demand management in terms of smart energy systems (Smart grid), we need a mathematical model of active consumer decision-making. Existing models either do not consider important aspects of consumer behavior, or are too complex for use in multi-agent simulation. A mathematical model of an active consumer is proposed, based on which we formulate and solve the problem of optimization of electrical appliances and consumer equipment, as well as determine the loading conditions of self-generation, under which the consumer problem allows simple and effective solution. The proposed approach is illustrated by equipment optimization of a single household.

A symmetrical electrochemical cell Bi3Ru3O11−35 wt % Bi2O3 porous electrode|Bi2O3−0.2 wt % B2O3 solid-molten electrolyte|Bi3Ru3O11−35 wt % Bi2O3 porous electrode is developed. The values of the cell ohmic and polarization resistances, Faraday efficiency, and oxygen permeation flux of the cell were measured using impedance spectroscopy and Coulomb volumetric technique at 740°C. These values are 0.046 and 0.077 Ω cm2, 97%, and 5×10–7 mol cm–2 s–1, respectively. The effect of wetting of the porous electrode surface on the polarization resistance was analyzed. The Bi3Ru3O11−35 wt % Bi2O3 and solid-molten Bi2O3−0.2 wt % B2O3 composites have a great potential to be used as the electrode and electrolyte materials in electrochemical oxygen generators.

We consider a model of patterning of one-dimensional foam-bubble chain confined in a bamboolike capillary. The discrete model of such a foam describes a distribution of foam films - lamellae that, like "bridges," span a capillary. This model is a kind of Ulam map, which admits many metastable distributions of lamellae in a bamboolike capillary as governing parameters (external pressure drop, lattice parameter, lamella tension, and gas compressibility) overcome certain barriers. In particular, some random distributions of bubble sizes over the chain are suited to solutions of the proposed discrete deterministic model. Randomization of lamella positions speaks in favor of the possibility of the glasslike patterning of foam in a bamboolike capillary. For such "chaotic" foam structures, the admissible pressure drop that the bubble chain can sustain, i.e., the so-called start-up, yield pressure drop, rises. We show that the start-up pressure drop depends upon the length of the chain nonlinearly. Only for short chains does it linearly depend upon the number of bubbles in the chain. For infinitely long chains, a saturation effect is observed; i.e., the critical pressure drop becomes independent of the chain length.

We revisit two known models of deterministically driven ratchets, which exhibit high energetic efficiency, with the goal to uncover similarities and differences in the principles of their operation. Both the models rely on adiabaticity of the potential change process, however, the adiabaticity that we deal with in the two cases is of different types, slow and fast. It is shown that in the former (latter) case the drift velocity is an even (odd) functional of the potential, with the notable consequence that for the adiabatically slow driven ratchet the necessary symmetry breaking occurs only due to time-dependent parametric perturbations, while the spatial asymmetry of the potential is a mandatory condition for the adiabatically fast driven ratchet to operate. To treat energetic characteristics, the models are restated in terms of traveling potential ratchets. With such an approach, we find that in these cases (i) the conditions of high energetic efficiency to be reached are similar, and (ii) the symmetry properties of the kinetic coefficients are different. Based on our results, a strategy for designing efficient Brownian motors is suggested.