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The paper considers the development and experimental study of the characteristics of a high-temperature motion parameter sensor based on molecular-electronic technology (MET) operating at elevated pressures. Studies were conducted in an extended temperature range (25–125 °C) with a static external pressure of up to 10 atm. A pilot plant based on a high-pressure chamber with the ability to output an electrical signal was specially designed and commissioned. A family of amplitude-frequency characteristics of a ME sensor in an extended temperature range was obtained for the first time. A theoretical model was constructed and verified to describe the transfer function of the sensor at high temperatures and pressures. The activation energies of active carriers were calculated, and a prediction was made about the possibility of using the developed devices for the needs of the oil and gas mining industries.

We consider a slowly condensing droplet levitating near the surface of an evaporating layer, and develop a mathematical model to describe diffusion, heat transfer and fluid flow in the system. The method of separation of variables in bipolar coordinates is used to obtain the series expansions for temperature, vapour concentration and the Stokes stream function. This framework allows us to determine temperature profiles and condensation rates at the surface of the droplet, and to calculate the upward force that allows the droplet to levitate. Somewhat counter-intuitively, condensation is found to be the strongest near the bottom of the droplet, which faces the hot liquid layer. The experimentally observed deviations from the classical law predicting the square of the radius to grow linearly in time are explained by the model. A spatially non-uniform phase change rate results in a contribution to the force not considered in previous studies, and comparable to droplet weight and the upward force calculated from the Stokes drag law. The levitation conditions are formulated accordingly, resulting in the prediction of levitation height as a function of droplet size without any fitting parameters. A simple criterion is formulated to define the parameter ranges in which levitation is possible. The results are in good agreement with the experimental data except that the model tends to slightly underpredict the levitation height.

Low frequency hydrophone with a frequency range of 1−300 Hz for marine seismic exploration systems has been developed. The operation principle of the hydrophone bases on the molecular electronic transfer that allows high sensitivity and low level self-noise at low frequencies (<10 Hz) to be achieved. The paper presents a stabilization method of the frequency response within the frequency range at a depth up to 30 m. Laboratory and marine tests confirmed the stated characteristics as well as the possibility of using this sensor in bottom marine seismic systems. An experimental sample of the hydrophone successfully passed a comparative marine test at Gelendzhik Bay (Black Sea) with the technical support of Joint-Stock Company (JSC) “Yuzhmorgeologiya”. One of the main results is the possibility of obtaining high-quality information in the field of low frequencies, which was demonstrated in the course of field tests.

We consider an example of four valued semantics partially inspired by quantum computations and negation-like operations occurred therein. In particular we consider a representation of so called square root of negation within this four valued semantics as an operation which acts like a cycling negation. We define two variants of logical matrices performing different orders over the set of truth values. Purely formal logical result of our study consists in axiomatizing the logics of defined matrices as the systems of binary consequence relation and proving correctness and completeness theorems for these deductive systems.

Experiments were carried out on flow boiling in mini- and microchannels with non-uniform heating (channel width 30 mm, size of centrally located heater 3x3 mm 2 ) with smooth and porous heater surfaces. It has been established that for that surfaces, the dependencies of the critical heat flux and heat transfer coefficients behave similarly, but in the case of porous surface, the critical heat flux increases more strongly with the growth of mass flow, and the heat transfer coefficients are higher due to developed boiling. Instead of a slowly developing boiling crisis with a large bubble constantly sitting on a smooth heater, boiling on porous surface was replaced by intense formation of small bubbles sweeping away large one. As a result, large bubbles either pulsate intensely or do not form at all until the moment of “classical” crisis - the sudden formation of stationary one with a sharp increase in surface temperature. This is true for both types of surfaces. But in the case of a smooth surface, the regime of a pulsating large bubble prevails, and on porous surface it ceases to form until “classical” crisis. The frequency of small bubble formation is significantly greater when boiling on porous surface.

The purpose of this work was to study the levitation of microdroplets of water condensate (about 10 μm in size) above a liquid surface and above a dry surface in a wide range of experimental parameters (microdroplets of condensate levitate due to the Stefan flow). The assigned tasks were studied using experimental methods. It was found that with increasing substrate temperature, the rate of droplet condensation and the rate of droplet evaporation increases. The rate of droplet evaporation over a dry substrate is much higher than the rate of droplet condensation over a wetted surface. The dependences of the height of levitation to the center of the drop on the radius of the drop levitating above the liquid layer at different values of the substrate temperature were also studied.

We consider a family of logical systems for representing entailment relations of various kinds. This family has its root in the logic of first-degree entailment formulated as a binary consequence system, i.e. a proof system dealing with the expressions of the form φ├ψ, where both φ and ψ are single formulas. We generalize this approach by constructing consequence systems that allow manipulating with sets of formulas, either to the right or left (or both) of the turnstile. In this way, it is possible to capture proof-theoretically not only the entailment relation of the standard four-valued Belnap's logic, but also its dual version, as well as some of their interesting extensions. The proof systems we propose are, in a sense, of a hybrid Hilbert-Gentzen nature. We examine some important properties of these systems and establish their completeness with respect to the corresponding entailment relations.

The relationship between formal (standard) logic and informal (common-sense, everyday) reasoning has always been a hot topic. In this paper, we propose another possible way to bring it up inspired by connexive logic. Our approach is based on the following presupposition: whatever method of formalizing informal reasoning you choose, there will always be some classically acceptable deductive principles that will have to be abandoned, and some desired schemes of argument that clearly are not classically valid. That way, we start with a new version of connexive logic which validates Boethius’ (and thus, Aristotle’s) Theses and quashes their converse from right to left. We provide a sound and complete axiomatization of this logic. We also study the implication-negation fragment of this logic supplied with Boolean negation as a second negation.

Two-dimensional direct Monte Carlo simulation of the flow around an evaporating water microdroplet in the air atmosphere above a dry or liquid surface has been carried out. We consider a cylindrical droplet 1 μm in diameter at a distance of 1 μm above the surface. The temperature of the droplet is taken equal to 65°C and 80°C. A significant decrease in the air concentration between the droplet and the liquid film surface is observed. The features of water vapor flow separately from the droplet surface and from the liquid film surface are considered. It is shown that, under certain conditions, condensation on the lower side and evaporation on the upper side on the droplet can occur simultaneously.

Tests were carried out on levitating microdroplets in a test section comprising a cuvette containing a thin layer of liquid. At the base of the cuvette, there is a round heating element with a diameter of 3 mm that is flush-sealed. We investigated how the size of the droplets changed due to condensation under different conditions, such as the thickness of the liquid layer and the humidity of the surrounding air. Our results showed that increasing the thickness of the liquid layer did not affect the growth of the droplets, but increasing the humidity of the air caused them to grow at a slower rate.