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According to the results of analytical, observational cross-sectional research on a random sample of the indigenous population of the Republic of Sakha (Yakutia) the association between the level of cardiovascular function and metabolic parameters was studied. It was found that 14 % of the participants bore the marks of "poor adaptation", 10 % - "failure of adjustment mechanisms." In senior age groups, the number of persons with dysaptation signs increased to 48 %. We found that the failure of adjustment mechanisms was manifested itself as negative changes in the metabolic profile and as increase of frequency of metabolic disorders and their combinations. Functional changes index based on the indicators of circulatory system, age, height and body mass shows good indices of sensitivity and specificity, and allows identifying 83 % of persons with multiple metabolic disorders correctly. The facts suggest the possibility of screening technology optimization in identifying risk factors of inveterate non-communicable diseases in limited health care resources. A holistic approach to the human body as a universal biosystem, knowledge deepening of its parameters under various external influences can help to optimize the methods of distress prevention.

Results of measurement and calculation of Eigen frequencies of coolant pressure oscillations in primary loops of NPP are presented. The simple calculation model based on equivalence of electric circuit with elastic wave propagation in liquids and gases, which gives a sensible interpretation of standing pressure waves sources is developed. It is shown, that pressurizer manifest itself as managed Helmholtz resonator generating a number of SPW (with Eigen frequencies of steam volume, water volume and their combination with coolant volume of respiratory line).

The accident at the Japanese Fukushima Daiichi nuclear power plant (NPP) caused by an earthquake showed the need of taking further efforts aimed at improving the design and engineering solutions for ensuring seismic resistance of NPPs with due regard to mutual influence of the dynamic processes occurring in the NPP building structures and process systems. Resonance interaction between the vibrations of NPP equipment and coolant pressure pulsations leads to an abnormal growth of dynamic stresses in structural materials, accelerated exhaustion of equipment service life, and increased number of sudden equipment failures. The article presents the results from a combined calculation-theoretical and experimental substantiation of mutual amplification of two kinds of external periodic loads caused by rotation of the reactor coolant pump (RCP) rotor and an earthquake. The data of vibration measurements at an NPP are presented, which confirm the predicted multiple amplification of vibrations in the steam generator and RCP at a certain combination of coolant thermal-hydraulic parameters. It is shown that the vibration frequencies of the main equipment may fall in the frequency band corresponding to the maximal values in the envelope response spectra constructed on the basis of floor accelerograms. The article presents the results from prediction of conditions under which vibroacoustic resonances with external periodic loads take place, which confirm the occurrence of additional earthquake-induced multiple growth of pressure pulsation intensity in the steam generator at the 8.3 Hz frequency and additional multiple growth of vibrations of the RCP and the steam generator cold header at the 16.6 Hz frequency. It is shown that at the elastic wave frequency equal to 8.3 Hz in the coolant, resonance occurs with the frequency of forced vibrations caused by the rotation of the RCP rotor. A conclusion is drawn about the possibility of exceeding the design level of equipment vibrations under the effect of external periodic loads caused by an earthquake when the vibration frequency of the reactor plant main equipment and the frequency of elastic waves fall in the frequency band corresponding to the maximal values of envelope response spectra.

The fabrication peculiarities of low-agglomerated yttria (Y2O3) nanopowders via thermal decomposition of sulfate-doped precursor with transient morphology were studied. It was determined that Y2(OH)5(NO3)x(CO2)y(SO4)z·nH2O (n=1-2) crystalline precursor underwent fragmentation and decomposition into isolated quasi-spherical Y2O3 particles upon calcination. Effect was connected with minimizing the free energy of the plate-like crystallites via reducing the contact surface until to the moment of spheroidization and attainment of isolation that occurred at T=1100 °C. Residual sulfate ions slowed down the surface diffusion during heat treatment thus retaining quasy-spherical morphology and low aggregation degree of Y2O3 nanopowders. Sulfate-doped yttria nanopowders with medium particle size of 53±13 nm possessed improved sinterability in comparison with undoped ones arising from finer particle size, narrower particle distribution and lower agglomeration degree.

Results of special measurements of coolant pressure oscillations in primary loops on unit No 3 of Novovoronezh NPP with VVER-440 are presented. Acoustical models and calculating algorithms for determinations of frequencies of acoustic standing waves (ASW) are designed. Models based on the Method of Electro-Acoustic Analogies gives a sensible interpretation of ASW sources. The calculated values of ASW frequencies for each acoustic element and for their compositions are presented. Identifying the sources of ASW in the first circuit held at all stages of the start-up power. Analysis of the results of comparison ASW rate with the measurement data of the main equipment vibration revealed a number of modes in which resonance of vibration with ASW occurs. Shown that developed approach can be used both in normal operation and in emergency modes for research and development of vibration - acoustic certification of reactor facilities; Improvements of process control and computer codes.

In the course of experimental modeling of diamond crystallization, the phenomenon of crystal twinning in the case of their mutual contact was found. The twinning probability comes up to about 50%, essentially surpassing that on the contact with the walls of the crystallization hamber (2%).

Metal vapor lasers pumped by transverse discharge after a conductor explosion in a vacuum seem to be promising from the point of view of their specific output parameters.1,2 This method of pumping can provide high specific output parameters from a number of metal vapors including refractory metals.3