We present spectroscopic observations of Nova Cas 2020(V1391 Cas) obtained using the Russian Turkish Telescope during different stages of its 2020 outburst.We followed the spectral evolution of the nova until it entered the nebular phase.The expansion velocity of the ejecta reached ∼780 km s -1 .The fluxes of the neutral [O I] lines at wavelengths 6300, 6364, and 5577 Å were used to calculate the electron temperature and the mass of neutral oxygen in the ejecta.We found average values T e = 4890 K ,M OI = 2.54 × 10 -5 M ⊙ which are consistent with the values calculated for other novae.We modeled the nova's ejected envelope 515 days after its discovery and found that the log elemental abundances by number relative to Hydrogen of the envelope are He = -0.7,C = -5.5, O = -2.5,N = -2.0 and Ne = -4.0.

It was revealed that the southern border of the range of spectacled sculpin Triglops scepticus runs in the region of 37°23′ N. It has been confirmed that the southern border of the range of Jordan’s sculpin T. jordani is located in the South Korean waters; of ribbed sculpin T. pingelii range, in the North Korean waters. In the Russian waters of the Sea of ​​Japan, Jordan’s sculpin occurs at depths of 14–230 m and water temperature of –1–13.8°C; ribbed sculpin, 30–424 m and –0.3–9.7°C; spectacled sculpin, 57–586 m and 0.3–4.3°C, respectively. In the warm period, the concentrations are somewhat shifted towards shallow waters; in the cold period, towards deep waters. The body length and weight of one-sized individuals increase with the degree of deep-water preference. The body length of Jordan’s sculpin reaches 20 cm; of ribbed sculpin, 23 cm; of spectacled sculpin, 26 cm. In all three species, females are larger than males. Females dominate populations of Jordan’s and ribbed sculpins while in spectacled sculpin the share of males is higher. In the northwestern part of the Sea of Japan spectacled and ribbed sculpins are planktivores consuming mainly hyperiids and euphasiids while Jordan’s sculpin is nectobenthivore with food dominated by mysids and small shrimps. During the spring—summer period mean values of daily rations of adult specimens of Jordan’s, ribbed and spectacled sculpins are 3.3, 2.4 and 1.8% of body weight, respectively. The biomass of g. Triglops species in the Russian zone of the Sea of Japan is about 2100 tonnes.

Gaia16aye was a binary microlensing event discovered in the direction towards the northern Galactic disc and was one of the first microlensing events detected and alerted to by the Gaia space mission. Its light curve exhibited five distinct brightening episodes, reaching up to I=12 mag, and it was covered in great detail with almost 25,000 data points gathered by a network of telescopes. We present the photometric and spectroscopic follow-up covering 500 days of the event evolution. We employed a full Keplerian binary orbit microlensing model combined with the motion of Earth and Gaia around the Sun to reproduce the complex light curve. The photometric data allowed us to solve the microlensing event entirely and to derive the complete and unique set of orbital parameters of the binary lensing system. We also report on the detection of the first-ever microlensing space-parallax between the Earth and Gaia located at L2. The properties of the binary system were derived from microlensing parameters, and we found that the system is composed of two main-sequence stars with masses 0.57±0.05 M_⊙ and 0.36±0.03 M_⊙ at 780 pc, with an orbital period of 2.88 years and an eccentricity of 0.30. We also predict the astrometric microlensing signal for this binary lens as it will be seen by Gaia as well as the radial velocity curve for the binary system. Events such as Gaia16aye indicate the potential for the microlensing method of probing the mass function of dark objects, including black holes, in directions other than that of the Galactic bulge. This case also emphasises the importance of long-term time-domain coordinated observations that can be made with a network of heterogeneous telescopes.

The concept of “science education for sustainable development” is considered, including environmental education, social and economic components. Emphasis is placed on the environmental component. The pedagogical conditions for the preparation of teachers of natural sciences for the sustainable development of society are identified and justified. The stages of their implementation are considered on the example of chemical education.

Bu calismada, AM CVn tipi yildizlar grubundan yeni bir kataklismik degisen Gaia14aae'nin gozlem sonuclarini sunuyoruz. Bu Gaia kaynaginin fotometrik verileri 2016-2017 yillarinda TUG'un RTT150, T100 ve T60 teleskoplari ile alinmistir. RTT150 ve T100'un 10 gecelik gozlemlerine gore, 49.7 dakikalik yorunge periyodunun degeri guncellendi ve 2.5 kadirden daha derin tutulmalar gosteren bir isik egrisi alindi. RTT150-TFOSC ile elde edilen isik egrisi ve tayf analizi de, Gaia14aae'nin bir orten polar olarak tanimlanmasina izin verdi. Ayrica T60 gozlemlerinden, yildizin BVR parlakliklarini belirledik.

the method of the university students’ engineering thinking development has been studied in the article, the experience of major universities of Germany implementing master programs in the field of sustainable resource management and waste management has been analyzed, the reasonableness of leading educational practices application by the specific topic lectures, the problem situations analysis, the logic of the engineering problems formulation has been substantiated.

Results from observation campaigns for the dwarf nova NY Ser during 2014 and 2016 are presented. Data were obtained on a total of 126 nights in 2014 that include 20 normal outbursts and one superoutburst and on 22 nights in 2016 that include 5 normal outbursts. The shape of the curves for the normal outbursts indicated the existence of “outside-in” and “inside-out” outbursts in this system. In different stages of outburst activity (quiescent state, outburst, and superoutburst) NY Ser manifests brightness oscillations with different periods. In the quiescent state and in normal outbursts, the orbital period 0d.097558(6) predominated. During the superoutburst we identified two stages in the evolution of superhumps: a stage in which the tidal instability of the accretion disk increases (A) and a stage with developed superhumps (B). Stage A for NY Ser has been identified for the first time, but its duration and period are not uniquely determined. In stage B, positive superhumps with an average period of 0d.10464(9) and a period excess of ε = 0.072 were recorded and negative superhumps with an average period of 0d.0938(1) and a period deficit of ε = -0.038 were detected for the first time.

The study deals with the features of the technique for simulating the capillary pressure curves of porous media on their X-ray microtomographic images. The results of a computational experiment on the immiscible displacement of an incompressible fluid by another in the pore space represented by a digital image of the Berea sandstone are presented. For the mathematical description of two-phase fluid flow we use Lattice Boltzmann Equation (LBM), and phenomena at the fluids interface are described by the color-gradient model. Compared with laboratory studies, the evaluation of capillary pressure based on the results of a computational filtration experiment is a non-destructive method and has a number of advantages: the absence of labor for preparation of fluids and core; the possibility of modeling on the scale of very small core fragments (several mm), which is difficult to realize under experimental conditions; three-dimensional visualization of the dynamics of filling the pore space with a displacing fluid during drainage and impregnation; the possibility of carrying out multivariate calculations for specified parameters of multiphase flow (density and viscosity of fluids, surface tension, wetting contact angle). A satisfactory agreement of the capillary pressure curves during drainage with experimental results was obtained. It is revealed that with the increase in the volume of the digital image, the relative deviation of the calculated and laboratory data decreases and for cubic digital cores larger than 1 mm it does not exceed 5%. The behavior of the non-wetting fluid flow during drainage is illustrated. It is shown that flow regimes under which computational and laboratory experiments are performed the distribution of the injected phase in directions different from the gradient of the hydrodynamic drop, including the opposite ones, is characteristic. Experimentally confirmed regularities are obtained when carrying out calculations for drainage and imbibition at different values of interfacial tension. There is a close coincidence in the average diameters of permeable channels, estimated by capillary curves for different interfacial tension and pore network model. The differences do not exceed 15%.

In this article, an analysis of the main thermal methods of waste utilization is carried out, a model laboratory for the thermal destruction of production and consumption wastes including medical was developed.

The main problems of waste management in accordance with the legislation are considered in the article. The economic benefits of separate waste collection are listed. The necessity of transition to a new level of waste management in the Republic of Tatarstan is determined.

We present the results of our long-term photometric and spectroscopic observations at the Russian–Turkish RTT-150 telescope for the optical counterpart to one of the best-known sources, representatives of the class of fast X-ray transients, IGR J17544-2619. Based on our optical data, we have determined for the first time the orbital and physical parameters of the binary system by the methods of Doppler spectroscopy.We have calculated theoretical spectra of the optical counterpart by applying non- LTE corrections for selected lines and obtained the parameters of the stellar atmosphere (T eff = 33 000 K, log g = 3.85, R = 9.5 R ⊙, and M = 23 M ⊙). The latter suggest that the optical star is not a supergiant as has been thought previously.

TUG is a part of the Gaia network. TUG telescopes of RTT150, T100 and T60 perform photometric and spectroscopic observations of unique objects discovered by Gaia. We present observations of Gaia sources based on http://gsaweb.ast.cam.ac.uk/alerts/alertsindex by using the telescopes. It is selected Gaia objects that are candidates in cataclysmic variables of the site.Follow-up and project observations of many Gaia objects were carried out at TUG. The flux variations of one of them Gaia14aat has been studied. It was found its range of 1.63 mag for 5 days. Some preliminary results of data processing for this object are presented. The study of the Gaia14aat and the others will be continued.

The results of a study of a sample of delta Scuti-type stars obtained from the observations with the BTA and RTT-150 are presented. Based on photometric data, we measured and analyzed the fundamental parameters of all the studied stars. For eight stars (for two of them for the first time), the fundamental parameters of the atmospheres (Teff, log g, [Fe/H]) and the chemical composition for 29 elements in the LTE-approximation are received using spectroscopic observations. The chemical composition analysis demonstrates both the solar abundances of chemical elements and the anomalies of chemical composition typical of Am stars in the studied sample of delta Scuti-type stars.

For over 10 years, we have carried out a precise radial velocity (RV) survey to find substellar companions around evolved G, K-type stars to extend our knowledge of planet formation and evolution. We performed high precision RV measurements for the giant star HD 208897 using an iodine (I2) absorption cell. The measurements were made at TÜBİTAK National Observatory (TUG; RTT150) and Okayama Astrophysical Observatory (OAO). For the origin of the periodic variation seen in the RV data of the star, we adopted a Keplerian motion caused by an unseen companion. We found that the star hosts a planet with a minimum mass of m2sini = 1.40 MJ, which is relatively low compared to those of known planets orbiting evolved intermediate-mass stars. The planet is in a nearly circular orbit with a period of P = 353 days at about 1 AU distance from the host star. The star is metal rich and located at the early phase of ascent along the red giant branch. The photometric observations of the star at Ankara University Kreiken Observatory (AUKR) and the Hipparcos photometry show no sign of variation with periods associated with the RV variation. Neither bisector velocity analysis nor analysis of the Ca II and Hα lines shows any correlation with the RV measurements.