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Sodium borohydride-closo-hydroborate Na3(BH4)(B12H12) exhibits high room-temperature ionic conductivity and high electrochemical stability. To study the dynamical properties of this mixed-anion compound at the microscopic level, we have measured the 1H, 11B, and 23Na nuclear magnetic resonance spectra and nuclear spin-lattice relaxation rates over the temperature range of 8–573 K. Our 1H and 11B spin-lattice relaxation measurements have revealed two types of reorientational jump motion. The faster motional process attributed to reorientations of the [BH4]− anions is characterized by an activation energy of 159 meV, and the corresponding reorientational jump rate reaches ~108 s−1 near 130 K. The slower process ascribed to reorientations of the larger [B12H12]− anions is characterized by an activation energy of 319 meV, and the corresponding reorientational jump rate reaches ~108 s−1 near 240 K. The results of the 23Na nuclear magnetic resonance measurements are consistent with the fast long-range diffusion of Na+ ions in Na3(BH4)(B12H12). The diffusive jump rate of Na+ is found to reach ~104 s−1 at 300 K and ~8 × 108 s−1 at 530 K. A comparison of these jump rates with the ionic conductivity data suggests the importance of correlations between diffusing ions.

The effect of temperature and pressure on the nucleation of the vapor phase and the velocity of the vapor front in the initial stage of activated boiling-up of n-pentane on the surface of a quartz fiber was studied. Using a developed approach combining the “pump-probe” and laser Doppler velocimetry methods, this velocity was tracked in the course of sequential change in the degree of superheating with respect to the liquid–vapor equilibrium line. The studied interval according to the degree of superheating was 40–100 °C (at atmospheric pressure). In order to spatiotemporally localize the process, the activation of boiling-up at the end of the light guide was applied using a short nanosecond laser pulse. A spatial locality of measurements was achieved in units of micrometers, along with a time localization at the level of nanoseconds. An increase in temperature at a given pressure was found to lead to an increase in the speed of the transition process with a coefficient of about 0.2 m/s per degree, while an increase in pressure at a given temperature leads to a decrease in the transition process speed with a coefficient of 25.8 m/s per megapascal. The advancement of the vapor front velocity measurements to sub-microsecond intervals from the first signs of boiling-up did not confirm the existence of a Rayleigh expansion stage with a constant velocity.

Advantages of using an external Fabry–Pérot interferometer (EFPI) as a high-speed local temperature deformation sensor are demonstrated for the fibre-optic circuit combining a powerful laser beam for surface heating with a low-power probing radiation. The difference in the formation of the heating and probing radiation provides a simple basis for varying the gap between the fibre end and the surface in order to change the ratio between the heating and EFPI measuring areas. Using an example of modelling the laser heating by radiation from a standard single-mode fibre, we demonstrate the possibility of employing the EFPI to measure the temperature deformation of the surface on a quasi-isothermal area with the temperature close to the maximum at gap values of more than 100 μm. With the condition of preliminary calibration, the proposed scheme can be used to evaluate the heat treatment of the surface with the speed of the applied photodetector. The practical possibilities of the method are demonstrated on examples of heating some metal and semiconductor samples by laser pulses of microsecond duration.

The article presents the results of a survey of specialists from the Orenburg region who provide assistance to patients with mental and behavioral disorders, regarding the experience of using telemedicine technologies. The purpose of the study was to assess the level of awareness of specialists about new technologies, the relevance of their application in the field of psychiatry, as well as to identify problems that arise in the process of implementing telemedicine in the practice of a doctor. The data obtained indicate a high interest in new technologies among doctors who previously participated in remote consultations. At the same time, among specialists who did not have experience with the telemedicine system, a low level of awareness about its capabilities and distrust of new technologies was revealed. Using the survey, it was possible to identify the main problems of telemedicine faced by specialists of the Orenburg region.

This article is devoted to the study of the phenomenon of superheating of partially miscible mixtures having a lower critical solution temperature and the thermal effect accompanying the relaxation of an unstable mixture, within the framework of the problem of high-density heat flux removal. The study was carried out by using the method of the controlled pulse heating of a platinum wire probe. The characteristic heating time was from 0.2 to 180 ms. The superheating degree of the mixture relative to the diffusion spinodal exceeded 100 K. The heat flux density from the heater surface reached 13.7 MW/m2. The object of research was an aqueous solution of polypropylene glycol-425 (PPG-425). The obtained results clearly indicate that such mixtures can be used as coolants in processes where the possibility of powerful local heat release cannot be excluded. They also form the basis for expanding the phase diagram by involving in the study not-fully-stable and unstable states of the mixture.

The article presents the results of the interaction of the federal telemedicine advisory center that provides telemedicine consultations on the profiles of «psychiatry» and «psychiatry-narcology» with the Volga Federal District.Despite the presence of a connection to the Telemedicine system of the Ministry of Health of Russia, almost half of the constituent entities of the Volga Federal District did not seek advice. The growing need and interest of regional doctors in consultations using telemedicine technologies was revealed.

The present article marks the 95th anniversary of the birth of Vladimir P. Skripov, author of the classic study of superheated and supercooled liquids. It presents a discussion based on the early work carried out by Skripov and his research team in Ekaterinburg during the 1950s and 1960s. Due to their pioneering nature, these works laid the foundation for the study of metastable liquid states. For various reasons, although they remain relevant to this day, these groundbreaking works remain unknown to most non-Russian-speaking readers. As well as elucidating the behavior of the heat capacity of a solution in the liquid–liquid critical region, the presented research also concerns the characteristic features of light scattering and free-convective heat transfer in the liquid–vapor critical region of a one-component system, discussing two options for the position of the superheated liquid spinodal on the phase diagram of water, including the area of supercooled states and negative pressures. The issues involved in the discussion are united by the fluctuating nature of such phenomena. Indeed, the very possibility of their experimental study is due to a significant increase in the scale of fluctuations of the corresponding quantities when approaching the critical point or spinodal. The ongoing development of the approaches proposed in these papers for solving contemporary problems in the thermophysics of superheated liquids is discussed.

Introduction. The prevalence of mental disorders, especially anxious and depressive calculi, among cardiac patients is significant. There is no doubt that it affects the cardiovascular system. The objective of the study was to analyze the prevalence of anxiety and depressive disorders among patients with cardiac pathology in the large hospital; and also to assess the provision of patients with this pathology with psychosomatic beds. Material and methods. In the course of the study, a questionnaire was conducted among 264 patients in the large cardiology department in St. Petersburg. The respondents were asked general and specialized (HADS questionnaire – screening for anxiety and / or depression) questions. With the help of special formulas on the basis of the received data, the required number of psychosomatic beds and regular positions of psychotherapists for the treatment of psychosomatic pathology for the city of St. Petersburg was calculated. Results. The findings confirmed the presence of a significant proportion of anxiety and / or depressive disorders among patients with diseases of the circulatory system. In addition to objective data, a significant percentage of interviewed patients associate the development of the underlying disease with emotional stress. Special attention is required by the age group of 60–75 years and older; men and women equally. It is important to note that the specific weight of clinically expressed forms is significant. This group of patients needs psychotherapeutic treatment in addition to the therapy of cardiac disease, which the respondents admit. Conclusions. Despite such a significant relevance, the organization of medical care for these patients in St. Petersburg is not enough. The perspectives of solving the problem were determined: an increase of stuff psychotherapists in multidisciplinary hospitals, integration of psychotherapeutic care into the outpatient stage of treatment.

Over the recent years, there has been an increase in the number of patients with psychosomatic disorders, as well an increase in the number of «masked depressions». High social significance of psychosomatic diseases is predetermined by the fact that it is extremely common among people of working age. The aim of the study was to analyze the medical and social composition of the patients at the psychosomatic department, as well as to show the efficiency of treatment in such department. The analysis of data obtained during the survey department of psychosomatic patients for anxiety and depressive disorders is presented. The survey was conducted by using the Hospital Anxiety and Depression Scale (HADS). The medical documentation of the department was also analyzed. The study found that the social composition of patients was heterogenous. Most of the patients (54.3 %) were in hospital with a diagnosis of organic anxiety disorder. It was revealed that the largest share among the somatic pathology accounted to such pathology as hypertension of the III degree in conjunction with coronary artery disease (20.7 %) and hypertension of the II stage (19.6 %). The efficacy of treatment in this department was proven. By the 20th day of hospitalization, 30 % of patients did not experience anxiety and/or depression. Combined symptoms of anxiety and depression were observed only in 14 % of patients by the 20th day of treatment.

Polyhydroborate salts represent the important class of energy materials attracting significant recent attention. Some of these salts exhibit promising hydrogen storage properties and/or high ionic conductivities favorable for applications as solid electrolytes in batteries. Two basic types of thermally activated atomic jump motion are known to exist in these materials: the reorientational (rotational) motion of complex anions and the translational diffusion of cations or complex anions. The present paper reviews recent progress in nuclear magnetic resonance (NMR) studies of both reorientational and diffusive jump motion in polyhydroborate salts. The emphasis is put on sodium and lithium closo-borates exhibiting high ionic conductivity and on borohydride-based systems showing extremely fast reorientational motion down to low temperatures. For these systems, we discuss the effects of order–disorder phase transitions on the parameters of reorientations and diffusive jumps, as well as the mechanism of low-temperature rotational tunneling.