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Chromium oxide ceramics may be considered as a new generation of ceramic materials for cutting tools with considerably improved high speed cutting performance. The present work is focused on the development of Cr2O3nanocomposite materials fabricated with the Field Activated Sintering Technique (FAST). The main objective of the proposed work is to study the influence of electric field on the densification process during FAST sintering of the materials in the Cr2O3-AlN system with nanosize microstructure. Additional objectives are to characterize mechanical properties of the obtained Cr2O3ceramics. The work aimed to develop composite materials based on Cr2O3-based nanoparticles for cutting, then to check their cutting properties and to work out the recommendations for their use for processing of various materials, accordingly.

Abstract: Propagation of electromagnetic waves in a waveguide with an arbitrary cross section is considered. The waveguide is filled with a magnetoactive anisotropic medium periodically modulated in space and time. The wave equations for the potentials of transverse electric (TE) and transverse magnetic (TM) fields are derived. Expressions for the TE and TM waveguide fields observed in the region of weak interaction between the signal wave and the modulation wave are found in the first approximation for small modulation indexes of the filling. The frequency near which strong (resonance) interaction between the signal wave and the modulation wave develops is expressed in an analytic form. The propagation of TE and TM waves in the strong-interaction region is investigated.

Abstract: The effects of daily and weekly academic loads on the psychological and cardio-and hemodynamic characteristics of students were analyzed. The self-estimated state of health, activity, and mood were evaluated with the use of the HAM (Health-Activity-Mood) questionnaire; the introversion and extraversion, neuroticism, and intelligence of the subjects were determined according to Eysenck; and the self-estimate the personal anxiety according to Spielberger, was evaluated. The main hemodynamic parameters (heart rate and arterial blood pressure) were measured and the systolic and minute blood volumes were calculated. The comparison of the dynamics of the parameters studied showed that there were two types of response of the students’ cardio-and hemodynamic parameters to academic load: sympathetic and parasympathetic. The parasympathetic response was found to be more adequate because the sympathetic response entailed the risk of overstrain and adaptation failure.

We studied the effect of continuous vibration and treatment with licorice root (Glycyrrhiza glabra L.) on peripheral blood red cells in rabbits. Active substances of licorice root accelerated metabolism in cells of the bone marrow erythroid stem, enhanced compensatory reserve of the organism, and increased animal's resistance to stress.

A study was made of the dynamics of psychophysiological parameters and the activities of the systems regulating the heart rate in prospective post-secondary students taking competitive entrance examinations. The responses of the regulatory systems to examination stress were of two types, sympathetic and parasympathetic, depending on the initial state of the autonomic nervous system and the psychophysiological personality traits.

Effects of examination stress on psychological characteristics and indices of the autonomic nervous system were studied in pupils of the eighth and tenth grades of high schools providing differential (test group, “Neuron” gymnasium) and general education (control group). General health state and levels of activity and mood (feeling, activity, mood; FAM) and neuroticism (according to Eysenck) were determined in both groups. Main hemodynamic indices (heart rate and blood pressure) were measured, and mathematical analysis of the heart rate by was performed according to Baevskii. Comparative analysis of psychophysiological tests and heart rate changes in the control and test groups points to a high tension in the cardiac rhythm regulation mechanisms and strong anxiety in schoolchildren in the differential education school. The character and depth of preexamination stress depended on the type of autonomic control of cardiac activity. Schoolchildren with sympathicotonic cardiac rhythm regulation showed the strongest emotional tension. Schoolchildren with the normotonic type of regulation were the most calm.

A comparative analysis of the dynamics of response latencies to a test signal (symbol + word) showed that, in the cases of random succession of associated stimuli and their strictly fixed sequence, there was a significant reduction of the response latencies with their subsequent stabilization at a certain level. After breaching the stereotype structure, most subjects emitted correct but strongly delayed responses to a shifted associated stimulus. Some subjects displayed incorrect responses; i.e., they responded to the “place” of the stimulus. After 25–30 days free of tests, the subjects correctly reproduced the previously established stereotype; however, the latencies were significantly longer than the initial value. Formulating the same tasks in the second (not native) language only increased the response latency without influencing its pattern.

A third-order (~) quasiclassical expansion of the free energy of an anharmonic crystal with many-body interactions is calculated using the self-consistent-field approach. The region of applicability of the quasiclassical theory is discussed on the basis of a numerical calculation of the thermodynamic characteristics of ionic crystals of potassium and rubidium halides in the quasiharmonic approximation.