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Investigation results on combustion of methane and ammonia diluted with hydrogen are presented. The effect of hydrogen addition on the physicochemical properties, flame flashback conditions, and boundaries of stable combustion is determined over a wide range of fuel-air equivalence ratios (from lean to rich mixtures).

The paper describes the results of an experimental study of a supersonic transverse flow around a cylindrical body. The complicated flow structure being formed is visualized by means of shadowgraphy and by seeding the flow with particles. The experiments are performed to study the classical transverse flow around the cylinder and the flow with ejection of a gas jet from the cylinder surface. Several locations of the hole over a circumference in the cylinder midsection are considered (the aspect ratio of the cylinder is λ = 3.2). The influence of the hole location on the flow structure formed due to supersonic interaction of the incident flow and the jet is described. The study yields new experimental data on the flow structure formed due to supersonic interaction of the incident flow and the jet for different locations of the hole. The flow patterns are provided and analyzed.

The paper describes a method for the synthesis of titanium carbide films using magnetron sputtering in a small-anode discharge. As a result, the synthesized films exhibit a density lower than that for the films produced by the stan-dard method of magnetron sputtering. The generate coating were subjected to annealing in oxygen-bearing or nitrogen atmosphere. The resulting films were studied using several characteristics and methods: volt-ampere characteristics of the magnetron discharge and the small anode, images from scanning electron microscopy, x-ray phase analysis, resistometry and spectral measurements for optical transparency. Our study demonstrated that the samples synthesized in a setup with an anode are thicker than those synthesized without anode. They also exhibit a smaller size of crystallites, lower transparency, forbidden band and a higher resistance. Taking into account the unchanged regime of magnetron operation, this indicates a reduced film density.

The paper discusses computational and experimental methods for evaluation the thermo-erosion characteristics of launch escape propulsion subsystems (LEPS) equipped with a thermal protection coating under natural operating conditions. Combustion mixture flow was simulated using a commercial CFD software. Based on the obtained data, heat flux distribution across the LEPS surface was determined. Firing tests conditions of thermal protection materials are also described. A gas-dynamic tunnel was used to reproduce the natural operating conditions. Quantitative characteristics of thermo-erosion resistance for materials were calculated based on the experimental results with corrections for the period of non-stationary coating heating.

It seems to be very promising to study the fundamental processes occurring during the mechanochemical production and subsequent combustion of composite powder fuels consisting of coal and waste of the wood, pulp and paper, and agricultural industries. The mechanisms of combustion of composite fuel particles made of lignocellulose and coal remain understudied. This paper examines the processes of ignition and flame combustion of composite fuel samples and mixtures obtained from sawdust and anthracite.

Methods of numerical simulation were applied to studying the interaction of high-temperature air jets arranged in a mixing chamber of a triple-jet plasma-chemical direct-flow reactor. Computations produce the 3D distributions for velocity and temperature in the mixing chamber. Simulation indicates the flow circulation zones and the spatial temperature distributions on the inner walls of the reactor. The study offers the data on the heat flux for inner walls depending on the existence/absence of a thermal protection coating on the inner walls. This approach can be used for numerical simulation for multiple-jet reactors with different designs and purpose.

The density and thermal expansion of a liquid rubidium-lead alloy containing 50 at. % Pb were investigated for the first time by the gamma-ray attenuation technique in the temperature range from the liquidus to ~1000 K. It was found that the molar volume of the Rb₅₀Pb₅₀ melt is 30 % less than the molar volume of an ideal solution of the same composition. The temperature dependence of the melt density is highly nonlinear, therefore the volumetric coefficient of thermal expansion decreases by more than 1.5 times with an increase in temperature from 864 to 1010 K. Based on modern concepts of the structure of liquid metal systems with partially ionic nature of interatomic interaction, the behavior patterns of the thermal properties of a liquid alloy are briefly analyzed.

The article critically examines the prevalent idea in analytical philosophy that the first-person singular pronoun “I” uniquely expresses the first-person perspective because of a direct correlation between an individual’s self-awareness and her ability to refer to herself with this pronoun. First, I outline the general idea of the problem concerning the linguistic expression of the first-person perspective. My focus is primarily on the problem of the cognitive significance of indexicals as well as the problem of ambiguity between de se and de re readings of the sentences involving indirect speech about an individual’s propositional attitudes. Many advocates of the criticized idea implicitly subscribe to the so-called “awareness condition”, while their explanation of how an individual acquires such awareness has a strong Cartesian flavor. Second, I argue that natural languages do allow impersonal use of the personal pronoun “I” and have multiple ways to express the first-person perspective. Both these facts challenge the idea of the unique role the pronoun “I” has in language systems. I propose to explain the lack of a single way to express the first-person perspective by referring to the context-dependent nature of language. To put it differently, the ways of expressing the first-person perspective depend on the context of use in communicative situations.

As is known, the Turing machine, developed long before the advent of computers, was not intended to take into account the interactions of programs, computers and other devices. However, the operation of the Internet and artificial intelligence involves different types of interactions. In modern computer science, various models have been created that take interactions into account. In this paper, I examined models of extended Turing machines and extended algorithms to determine whether the Turing machine model is adequate to describe and solve the problems that these models can handle. I showed that extended Turing machines correctly describe the behavior of the Turing model and successfully solve the problems that it can handle. Also, in the article I described the problem of controlling the movement of a car driven by a robot by a Turing machine, it does not cope with this problem, but extended Turing models provide a solution to it. Therefore, the question of the strict relationship between the capabilities of Turing machines and extended Turing machines remains open.

In the process of the development of modern science, researchers have obtained a large number of results, which make their own unique contribution to the formation of scientific knowledge. After F. Bacon, it is generally accepted that the scientific result or scientific knowledge, first of all, indicates knowledge obtained in an experiment or empirically. At the same time, as the history of science shows, experiments, as a rule, were not set up and carried out randomly, but were mainly conditioned by hypotheses formulated by great scientists in the process of their thinking on a special kind of being. In this regard, without denying the importance of an experiment in the process of scientific knowledge, we will formulate the following problem: does scientific knowledge arise in an experiment or is an experiment only a means of manifestation of a hypothetical idea of the general content of a special kind of being that has already arisen in thinking? Answering this question, we come to the conclusion that scientific knowledge constantly passes through аbstrаct, dialectical and speculative moments of a completely reasonable logical method of thinking. These moments of thinking are necessary prerequisite and condition for the emergence of scientific knowledge. Thus, it is revealed that scientific knowledge does not arise in the experiment itself, but is comprehended as such through repeated passage of moments of thinking.