The results of the analysis of the radiation state of environmental objects in the sanitary protection zone (SPZ) and surveillance zone (SZ) of the research nuclear reactor (RNR) WWR-M of the ...Institute for Nuclear Research of the National Academy of Sciences of Ukraine (INR) for 2021 are analyzed and compared with the data for previous years (from 2016 to 2020). The levels of total beta activity of sedimentary dust and atmospheric precipitation and wastewater from the main reservoirs of INR, the concentration of beta-active aerosols in the surface layer of atmospheric air, as well as the content of 137Cs radionuclide in soil and vegetation samples, were studied. The research was conducted in the laboratory of the Center for Ecological Problems of Atomic Energy of INR. The obtained results show that in 2021 there was no excess of the values of controlled parameters compared to previous years. There was also no significant difference in the specific activity of the radionuclide 137Cs in soil and vegetation samples from SPZ and ZS. Studies conducted in the period from 2016 to 2021, allowed to accumulate significant factual material on the radiation situation in the sanitary protection zone and surveillance zone and to substantiate the conclusion about the absence of man-made radioactive contamination of the environment due to the operation of RNR WWR-M of INR of NAS of Ukraine.
Context. We present a spectral analysis of the binary G 224-58 AB, which consists of the coolest M extreme subdwarf (esdM5.5) and a brighter primary (esdK5). This binary may serve as a benchmark for ...metallicity measurement calibrations and as a test bed for atmospheric and evolutionary models for esdM objects. Aims. We perform the analysis of optical and infrared spectra of both components to determine their parameters. Methods. We determine abundances primarily using high-resolution optical spectra of the primary. Other parameters were determined from the fits of synthetic spectra computed with these abundances to the observed spectra from 0.4 to 2.5 microns for both components. Results. We determine Teff = 4625 ± 100 K, log g = 4.5 ± 0.5 for the A component and Teff = 3200 ± 100 K, log g = 5.0 ± 0.5, for the B component. We obtained abundances of Mg / H = + − 1.51 ± 0.08, Ca/H = − 1.39 ± 0.03, Ti/H = − 1.37 ± 0.03 for alpha group elements and CrH = − 1.88 ± 0.07, Mn/H = − 1.96 ± 0.06, Fe / H = − 1.92 ± 0.02, Ni/H = − 1.81 ± 0.05 and Ba/H = − 1.87 ± 0.11 for iron group elements from fits to the spectral lines observed in the optical and infrared spectral regions of the primary. We find consistent abundances with fits to the secondary albeit at lower signal to noise. Conclusions. Abundances of different elements in G 224-58 A and G 224-58 B atmospheres cannot be described by one metallicity parameter. The offset of ∼0.4 dex between the abundances derived from alpha element and iron group elements corresponds with our expectation for metal-deficient stars. We thus clarify that some indices used to date to measure metallicities for establishing esdM stars, based on CaH, MgH, and TiO band system strength ratios in the optical and H2O in the infrared, relate to abundances of alpha-element group rather than to iron peak elements. For metal deficient M dwarfs with Fe / H < − 1.0, this provides a ready explanation for apparently inconsistent metallicities derived with different methods.
Rate of the turbulent energy dissipation arising due to the breaking surface waves is estimated based on the experimental data on near-surface turbulence. The studies were carried out on the ...oceanographic planform in the Black Sea coastal zone by the specialized measuring complex 'Sigma-1'. To analyze the data, specific hydrometeorological conditions including high wind speed and significant number of breaking waves were chosen from the total data array. The turbulent energy dissipation rate per unit of volume ε is calculated using the spectra of velocity fluctuations based on the Kolmogorov hypotheses on the inertial-range spectrum of turbulence. The dissipation rate per unit of area of the sea surface is calculated by the over depth integrating the values of ε defined on all the measurement horizons with their extrapolation up to the surface and bottom. The results provided by the experiment data are compared to the wave energy losses due to braking calculated by the Phillips model (1985).The values of the breaking parameter b calculated under the assumption on its model dependence upon the wave number are smaller than the estimates obtained by the other authors. The second method of calculation implies an assumption that the breaking parameter is constant in every single experiment and does not depend on the wave number. The obtained values of b are of moderate spread and also smaller (within one order of magnitude) than the estimates obtained by the other authors. In this case the values of b are satisfactorily approximated by the constant bc ~- 1.31·10-4. Discrepancy between the obtained results and those in the other sources can be conditioned by the differing waves' characteristics and methods for estimating the dissipation rate.
Photometric studies of the dwarf nova ASASSN-19fy in the “period gap” were carried out in 2020-2021 over 24 nights at the Crimean Astrophysical Observatory of the Russian Academy of Sciences and 3 ...nights at the Sanglokh International Astronomical Observatory of the Institute of Astrophysics, National Academy of Sciences of Tajikistan. The observations covered a superoutburst, two successive rebrightenings, and a slow return to the pre-outburst (quiescent) state. During this time, superhumps were observed, in the evolution of which the stages of developed superhumps “B,” their damping “C,” and a transition between them were identified. The average period of the superhumps in stage “B” was 0.09278(13) days and it was found its increase during this stage at a rate of (dP / dT) / P = 10·10
–5
. In stage “C” the period of the superhumps was equal to 0.092289(15) days. It is shown that ASASSN-19fy is the twelfth object to join the group of long-period dwarf novae similar to WZ Sge-type stars.
The number of people in need of phoniatric help is constantly increasing. People with voice problems are of working age. The object of researche: lowering risk of progression of vocal pathology based ...on a comprehensive system of management of teachers’ occupational risks. Hygienic, epidemiological, sanitary-statistical, in-depth medical examination method and mathematical-statistical methods were applied. Working conditions of teachers are characterized by complex effects of harmful production factors, which can reach 3d degree of 3d class of harmful work by intensity (according to the calculated points 3,63), 2nd degree of 3d class of harmful pressure on vocal apparatus (27,52±3,54 hours), 1st degree of 3d class of harmful by equivalent noise level and unfavorable microclimate. The most widespread pathologies of the vocal apparatus are chronic hypertrophic laryngitis (190,20±22,61) and chronic catarrhal laryngitis (131,00±15,07 cases). Almost 70% of occupational laryngitis cases are in the age group of 46-60 years. The critical length of service influenced by voice load is 10-19 years. The length of service more than 20 years in conditions of voice load increases the etiological percent of occupational pathology causes to 81,8%. Therefore, an age of 45,8±0,5 and older is dangerous for the occupational laryngitis progression and requires a special approach of development and implementation of preventive measures aimed at maintaining of occupational health. Suggested complex of measures increase the healthy life by 7,3 years and reduce the loss of healthy life years determined by the impact of voice activity by 7,1 years. At the same time for physical health component (PH) by 4,5 and 4,3, and the psychological health component (MH) by 10,3 and 10,1 years QALY respectively.
We study the Hamiltonian geometry of systems of hydrodynamic type that are equivalent to the associativity equations in the case of three primary fields and obtain the complete classification of the ...associativity equations with respect to the existence of a first-order Dubrovin–Novikov Hamiltonian structure.
The main factors limiting the application of high-temperature creep-rupture resistant titanium alloys synthesized from powder components by pressing and subsequent vacuum sintering for the ...manufacture of parts for gas turbine engines are analyzed. The method for synthesizing the VT1-0 alloy and an alloy whose chemical composition corresponds to the high-temperature creep-rupture resistant VT8 alloy is described. Their chemical and phase composition, strength, hardness, and distribution of doping elements are examined. Upon analysis of the composition, structure, and properties of the samples produced from the test alloys synthesized from PT5 titanium powders with different particle sizes by powder metallurgy methods, it was concluded that semi-finished products could be produced from the VT1-0 and VT8 titanium alloys. The effect of the particle size of the titanium matrix on the chemical composition of the synthesized alloys is studied. The chemical composition of the test alloy complies with the industry standard for semi-finished products of hightemperature creep-rupture resistant titanium alloys. The influence of the particle-size distribution of titanium powder on the strength, hardness, and residual porosity of the synthesized alloys is established. Regardless of the particle size of the powder mixture matrix (ranging from 40 to 400 μm), the strength, ductility, and hardness of the test VT8 alloy do not comply with the requirements of standards OST 90002–70 and OST 90006–70, which govern these properties for bars and blanks of gas turbine engine blades. It is concluded that a series of measures are required to eliminate the residual porosity and impart the blade structure to the material to improve the strength properties.
Photometric studies of the type SU UMa dwarf nova NY Her were made during 2017 and 2020 at the Crimean Astrophysical Observatory and at the Sanglokh Observatory over a total of 77 nights. These ...observations covered two superoutbursts, four normal outbursts, and the quiescent state between them. In 2017 the supercycle was 62 days, and the cycle, 13-14 days. Positive superhumps with an average period of 0.07594 days and a variable amplitude not exceeding 0
m
.15 were observed during the superoutbursts. In the quiescent state between outbursts, as well as in the ascending and descending branches of the normal outbursts, negative superhumps with an average period of 0.071269 days were recorded. Their amplitude ranged over 0
m
.3-1
m
.5 in the quiescent state. The period of the negative superhumps manifested cyclical increases between normal outbursts, which is consistent with the prediction of a cyclical change in the radius of the accretion disk in terms of the thermal-tidal theory of the instability.
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