Data on the development of the circulating fluidized bed (CFB) technology for combustion of fuels in large power generating units are examined. The problems with raising the steam parameters and unit power of boilers with a circulating fluidized bed are examined. With the boiler system at the 460 MW unit at Lagisza (Poland) as an example, the feasibility of raising the efficiency of units with CFB boilers through deep recovery of the heat of the effluent gases and reducing expenditure for in-house needs is demonstrated. Comparative estimates of the capital and operating costs of 225 and 330 MW units are used to determine the conditions for optimum use of CFB boilers in the engineering renovation of thermal power plants in Russia. New areas for the application of CFB technology in CO 2 capture are analyzed in connection with the problem of reducing greenhouse gas emissions.

The current status of circulating fluidized bed (CFB) technology employed at foreign TPPs is briefly analyzed.. It is demonstrated that CFB technology is entirely suitable for the building of 225-and 330-MW units with enhanced steam parameters, and also for replacement of boilers at TPP with cross links. Placement of prospective standards into effect for harmful effluents, and diversification of fuel supply are important advantages of this technology. It is shown that CFB boilers based on unified subassemblies could be built at least for groupings of fuels. Results of mathematical modeling of processes in furnaces of CFB boilers, which are in satisfactory agreement with data obtained from simplified engineering methods, are presented. Further improvement of the mathematical model, and a series of analyses of the furnace circuit in the nonsteady statement with a supercomputer are being traced.

Sensitivity characteristics of seven commercial ELISA test systems for the detection of antibodies to hepatitis C virus were assessed using control panels consisting of: (i) serial dilutions of pooled sera highly reactive for anti-HCV; (ii) serial dilutions of RIBA 3.0 HCV SIA positive control; and (iii) natural (non-diluted, non-spiked) sera low-reactive for anti-HCV. "Dilutional sensitivity" values estimated with these two kinds of highly reactive samples did not coincide and were not found to correlate with the proportion of natural low-reactive specimens detected by each test. Thus, laboratories assessing sensitivity of anti-HCV ELISAs should take into consideration the nature and properties of the control material used. Natural low-reactive control specimens are preferable because they adequately reflect the real serological picture of early stage of HCV infection.

The high level of mental and physical training loads on the body of students requires a good development of adaptive-compensatory mechanisms, stress resistance, psychological endurance. On the other hand, modern research indicates the low level of health of students and their maladaptation to high levels of stress, which determines the relevance of the study of changes in the functioning of the cardiovascular system to develop measures to correct adverse conditions and improve physical and mental health. The purpose of the work was to determine the features of changes in heart rate variability of students under the influence of mental and physical activity, taking into account gender characteristics. Material and methods. The article presents the results of a study of heart rate variability of 128 students (65 male and 63 female) of the Petro Mohyla Black Sea National University aged 17-25 years. All students had indicators of variability of resting heart rate, after mental and physical activity on short recordings of the cardio signal (2 minutes), obtained with the help of rhythm "MPFI rhythmograph-1" and EasyHRV software (LLC "ASTER-IT", Kharkiv). We used the proofreading method by Kryvonosov M. V. et al. (2001), which consisted of finding and selecting a specific letter in test tables for 20-25 minutes. Aerobic exercise consisted of running a distance of 2000 m on a rowing machine Concept-2 for 10 minutes. The research results were processed using descriptive statistics and non-parametric criteria. Results and discussion. The results of research showed that at rest almost all statistical and temporal indicators of heart rate variability of boys and girls were within the age norms. Mental load did not lead to a significant deterioration of the indicators studied, which indicated the stereotype of reaction. Exercises led to a significant deterioration in the cardiovascular system of students, as evidenced by a significant decrease relative to the lower limit of the norm of SDNN and RMSSD (almost four times); increase in the index of autonomic balance (above the upper limit of the norm by 90% for boys and 71% for girls); exceeding the upper limit of the norm twice with the indicators of vegetative rhythm and regulatory processes adequacy; an increase in the stress index of boys by 7 times and more than 5 times for girls, which led to exceeding the upper limit of the norm by more than 4-5 times; reduction of the total power of the cardio signal spectrum in boys by 9 times, and by 8 times in girls; power of the spectrum of very low frequencies twice, low frequencies by 5-8 times, high frequencies by 6-11 times. Conclusion. Low energy spectral parameters, as well as reducing the variability of cardio intervals and increasing the stress index are manifestations of hyperadaptive response to exercise and indicate low adaptive capacity of students, which requires the introduction of rehabilitation activities

The process of students’ adaptation should be considered as a dynamic and integrated process of forming the necessary skills to meet the needs that arise during study at a higher education institution. The purpose of the study was to establish the nature of psychophysiological indicators of students with different types of autonomic regulation in conditions of physical and mental activity. Materials and methods. The article presents the results of a study of the psychophysiological indicators of 128 students (65 boys and 63 girls) of the Petro Mohyla Black Sea National University aged 17-25 years. All students had psychophysiological indicators before and after mental and physical activity measured with the device for psychophysiological research «PFI-2». The students were divided into groups according to the types of vegetative regulation, according to the method of express assessment of the functional state of regulatory systems according to N. I. Shlyk. All students had indicators of heart rate variability at rest on short recordings of the cardiac signal (2 minutes), obtained with the help of the rhythm «MPFI-rhythmograph-1». Proofreading method according to the method of M. V. Krivonosov et al. (2001) was used as a mental load, which consisted of finding and selecting a specific letter in test tables for 20-25 minutes. Aerobic exercise consisted of taking a distance of 2 km on a rowing machine Concept-2 for 10 minutes. Results and discussion. The obtained results showed that after the mental load, the psychophysiological indicators of students of all groups did not change reliably, which led to the formation of adaptation mechanisms. However, only the students of group 3 have grouped reliable changes in some indicators of the correct sample, which reflects the state of development of mobilization. After physical exertion, changes in individual and typological indicators were observed in representatives of groups 1 and 3. A significant decrease in the indicators of functional mobility of nervous processes and the strength of nervous processes indicates the mobilization of the body's reserves. The value of the dynamics of nervous processes in group 1 significantly increased after physical exertion, which indicates the development of a state of fatigue. There was also a significant increase in the number of anticipated/delayed reactions in group 3, which indicates the predominance of excitation processes over inhibition. After physical exertion, no significant changes in psychodynamic parameters were observed, but in group 2, the time of the complex simple visual-motor reaction significantly increased, which indicates the development of a state of fatigue. After physical exercise, the students of group 3 have observed significant changes in the values of the correction test indicators, which indicates the mobilization of the body's reserves. Conclusion. The analysis of the results of the study made it possible to establish that the mental load had an insignificant effect on the representatives of group 3. After physical exertion, significant changes were observed in representatives of all groups, except for group 4