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A single-phase physico-mathematical model of a high-speed waterjet forming process that uses the underwater abrasive waterjet cutting technology while an abrasive-liquid flow under a pressure ranging from 60 to 80 MPa passes through the jet-forming path of a mobile abrasive waterjet machine has been developed. The results of a numerical experiment are presented. It has been shown that the main structural parameters of the internal profile of the jet-forming element (the profile of the focusing cavity, diameter and length of the output-channel) influence the geometric and kinematic parameters of the formed jet and the consumption of the hydro-abrasive suspension.

We substantiate the recommendations for improving the efficiency of hydro- and hydroabrasive cutting of the honeycomb structures that are widely used in aircraft and rockets, obtained by numerical solving of the spatial dynamic problem with allowance for the physico-mechanical and kinematic parameters of a high-speed jet, the physico-mechanical and structural parameters of the treated honeycomb structure, and the parameters of the technological treatment (feeding and the impact angle of the jet with the face surface of the blanks). A physico-mathematical model and a method of numerical analysis of the process have been developed. The influence of the above parameters on the quality of the surfaces of the treated blanks is illustrated. The results of the calculations are compared with the experimental data.

This paper describes the principles of visualization and analysis of thermal fields generated by different physiological processes around the facial area and in the environment. The dynamics of these fields was studied and their possible application for quantitative evaluation of psychophysical parameters is analyzed using infrared thermography with high spatial and temporal resolution. A software module has been developed and tested for combining infrared and visible camera images. A technique was proposed for complex recording and analysis of central and peripheral nervous activities using a thermal camera that captures three types of temperature fields that vary with time around the facial area: exhaled gas flows, cutaneous blood circulation, and sweat gland activity.

The Monte-Carlo procedure and a new method to determine the chirality of water environments and their classification were used for the first time to study the chiral properties of small water clusters such as (H2O) n , K+(H2O) m , and Na+(H2O) m (n = 4–8, m = 5–10) at a temperature of 1 K. The probability that the studied water clusters will be chiral becomes higher at an increase in their size. It is revealed that a small water cluster devoid of impurities is not dominated by one of the arrangements (right or left). The addition of K+ or Na+ impurity ions does not change the equilibrium distribution of right and left configurations in the 10 000-sample set.

In this paper, a method for distinguishing between liquid samples that are sensitive to the influence of low-intensity physicochemical factors is described. It is based on the calculation of the initial moments of the intensity distribution series in their infrared spectra and comparison of the obtained values with each other. Reliable signs of the coincidence of liquid samples that were obtained in the experiment were used to distinguish distilled water at–0.5 ± 0.5 and–3.0 ± 0.5±C, and at–3.0 ± 0.5 and–5.0 ± 0.5°C, and to distinguish between distilled and tap water at 25.0 ± 0.5°C. For each sample, the moments were calculated for the bending (1640 cm–1), combination (2090 cm–1), and stretching (3370 cm–1) water absorption bands. It was found that when comparing distilled water at–0.5 ± 0.5 and–3.0 ± 0.5°C the greatest differences are observed for the bending band (50%). When considering distilled water at–3.0 ± 0.5 and–5.0 ± 0.5°C, the greatest differences occur for the stretching band (54%). When comparing distilled water at 25.0 ± 0.5°C and tap water at 25.0 ± 0.5°C, the greatest differences were observed for the bending band (86%).

The temperature dependence of the bending ν2, combination ν2 + ν L , and stretching (ν1, ν3, 2ν2) absorption bands in the infrared spectra of supercooled water with a temperature-change step Δt from 2 to 2.5°C was studied using an advanced infrared Fourier spectrometer. It was found that the frequency of the maximum of the stretching absorption band (2700–3700 cm−1) decreases with the reduction of the water temperature from −0.5 to −5.0°C. The frequency of the maximum of the combination absorption band (2130 cm−1) increases with the reduction of the water temperature in a range from −3.0 to −5.0°C. The frequency of the maximum of the absorption band of bending oscillation (1640 cm−1) is invariable with a reduction of the water temperature from −0.5 to −5.0°C.

Computer simulation of water clusters (H2O)n, Na+(H2O)n and K+(H2O)n (n ≤ 8) at temperatures of 1 and 300 K was carried out using the Monte Carlo method. All the types of the hydrogen-bond network structures at equilibrium configurations of the water clusters and, among them, the most probable ones at temperatures of 1 and 300 K, were detected. The analysis of the most probable types of hydrogen-bond networks at equilibrium configurations of water clusters revealed that clusters with n water molecules inherit the configuration of clusters with n − 1 water molecules with an accuracy of one hydrogen bond.

Changes in the dielectric constant and dielectric loss tangent of water that was first subjected to impact loads under the action of an alternating magnetic field were determined quantitatively using a micro-wave system, which allows solution of the inverse problem. The results of measurements of the optical spectrum of water in the “transmission” mode, which was subjected to a shock load, in comparison with the optical spectrum of distilled water, are described.

It was shown experimentally that the infrared spectra of melted and never-frozen distilled water differed at frequencies of 1640 and 2130 cm−1. This is explained by the long relaxation of water molecules structures to an equilibrium state in melt water. It was suggested that near the frequency 2130 cm−1 there was a bigger influence of dissolved gas relaxation on the value of the transmitted intensity of infrared radiation than near the 1640 cm−1 line.