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Context. Recent observational data show that the Milky Way (MW) galaxy contains about 170 globular clusters (GCs). A fraction of them is likely formed in dwarf galaxies accreted onto the MW in the past, while the remaining of clusters are formed in-situ. Therefore, different parameters, including orbits, of the globular clusters is a valuable tool for studying the Milky Way evolution. However, since the evolution of the 3D mass distribution of the MW is poorly constrained, the orbits of the clusters are usually calculated in static potentials. Aims. In this work, we study the evolution of the GCs in several external potentials, where we aim to quantify the effects of the evolving galaxy potential on the orbits of the GCs. Methods. For the orbits calculation we used five MW-like potentials from IllustrisTNG-100 simulation. The orbits of 159 GCs were integrated using a high-order N-body parallel dynamic code phi-GPU, with initial conditions obtained from recent Gaia DR3 catalogues. Results. We provide a classification of the GCs orbits according to their 3D shapes and association with different components of the MW (disk, halo, bulge). We also found that the globular clusters in the external potentials have roughly similar energy-angular momentum distributions at the present time. However, both total energy and total angular momentum of the GCs are not conserved due to time-varying nature of the potentials. In some extreme cases, the total energy can change up to 40% (18 objects) over the last 5 Gyr of evolution. We found that the in-situ formed GCs are less affected by the evolution of the TNG potentials as compared to the clusters which are likely formed ex-situ. Therefore, our results suggest that time-varying potentials significantly affect the orbits of the GC, thus making it vital for understanding the formation of the MW., Comment: 19 pages, 17 figures, 2 tables, accepted for publication in Astronomy and Astrophysics

Using the data from Gaia (ESA) Data Release 2 we performed the orbital calculations of globular clusters (GCs) of the Milky Way. To explore possible close encounters (or collisions) between the GCs, using our own developed high-order phi-GRAPE code, we integrated (backward and forward) the orbits of 119 objects with reliable positions and proper motions. In calculations, we adopted a realistic axisymmetric Galactic potential (bulge + disk + halo). Using different impact conditions, we found four pairs of the six GCs that may have experienced an encounter within twice the sum of the half-mass radii (collisions) over the last 5Gyr: Terzan3 - NGC 6553, Terzan 3 - NGC 6218, Liller 1 - NGC 6522 and Djorg 2 - NGC 6553., Comment: Accepted for publication in Advances in Astronomy and Space Physics (http://aasp.kiev.ua). arXiv admin note: substantial text overlap with arXiv:2201.06891

Using the data from Gaia (ESA) Data Release 2 we performed the orbital calculations of globular clusters (GCs) of the Milky Way. To explore possible close encounters (or collisions) between the GCs, using our own developed high-order phi-GRAPE code, we integrated backward and forward the orbits of 119 objects with reliable positions and proper motions. In calculations, we adopted a realistic axisymmetric Galactic potential (bulge + disk + halo). Using different impact conditions, we found four pairs of the six GCs that may have experienced an encounter within twice the sum of the half-mass radii (collisions) over the last 5Gyr: Terzan3 - NGC 6553, Terzan 3 - NGC 6218, Liller 1 - NGC 6522 and Djorg 2 - NGC 6553., Comment: Accepted for publication in Advances in Astronomy and Space Physics (http://aasp.kiev.ua). arXiv admin note: substantial text overlap with arXiv:2201.06891

Головною умовою вирощування пшениці озимої є додержання правильної агротехніки та створення умов високої культури землеробства. Удосконалення технології в сучасних умовах виробництва зерна потребує знання фенологічних і морфологічних особливостей рослин, підбору адаптивних сортів, засобів захисту культури від шкодочинних об’єктів, особливо бур’янів та уникнення негативного впливу на довкілля. Метою наукових досліджень було виявлення ефективності осіннього і весняного гербіцидних обробітків на урожайність та якість пшениці озимої. Для даних досліджень використовували сорти пшениці – Мескаль та Паляниця. Нами встановлено, що термін гербіцидного обробітку суттєво впливає на забур’яненість посіву, формування урожаю та якісні показники зерна. Осіння гербіцидна обробка посівів пшениці озимої препаратом Марафон, внесення одночасно з посівом 150 кг/га діамофоски та дворазове підживлення рослин аміачною селітрою сприяє отриманню в умовах дерново-підзолистих супіщаних ґрунтів урожайності зерна сортів Мескаль та Паляниця на рівні 4,8–5,0 т/га. Нами виявлено, що на необроблених гербіцидами ділянках кількість бур’янів збільшувалася від 80 до 130 шт/м2. Внесення гербіциду Марафон (4 л/га) восени забезпечило зменшення кількості бур’янів у посівах пшениці озимої з 86–90 шт/м2 до 8–10 шт/м2. Весняне внесення цього гербіциду було менш ефективним і показники забур’яненості на цих ділянках зменшувалися зі 100–110 шт/м2 до 24–27 шт/м2. Весняне застосування гербіциду Пріма (0,5 л/га) на посівах пшениці показало найгірші показники щодо кількості бур’янів (30–32 шт/м2). За осіннього обробітку гербіцидом Марафон кількість продуктивних стебел була найбільшою: у сорту Мескаль – 553 шт/м2, а у сорту Паляниця – 560 шт/м2. Зменшення забур’яненості посівів пшениці озимої не лише вплинуло на кількість продуктивних стебел, а й значно покращило якість зерна., The main condition for growing winter wheat is the observance of proper agricultural techniques and the creation of conditions for high agricultural culture. Improving the technology in modern conditions of grain production requires knowledge of phenological and morphological features of plants, selection of adaptive varieties, means of protection of crops from harmful objects, especially weeds and avoidance of negative impact on the environment. The aim of the research was to identify the effectiveness of autumn and spring herbicide treatments on the yield and quality of winter wheat. Wheat varieties Meskal and Palyanytsia were used for these studies. We found that the term of herbicide treatment significantly affects the weediness of crops, crop formation and grain quality. Autumn herbicide treatment of winter wheat crops with Marathon, simultaneous application of 150 kg/ha of diammophos and double fertilization of plants with ammonium nitrate contributes to obtaining in the conditions of sod-podzolic sandy soils grain yields of varieties Meskal and Palyanytsia at level of 4,8–5,0 t/ha. We found that in areas not treated with herbicides, the number of weeds increased from 80 to 130 pcs/m2. The application of the herbicide Marathon (4 l/ha) in autumn ensured a reduction in the number of weeds in winter wheat crops from 86–90 pcs/m2 to 8–10 pcs /m2. Spring application of this herbicide was less effective and weed rates in these areas decreased from 100–110 pcs/m2 to 24-27 pcs/m2. Spring application of Prima herbicide (0.5 l/ha) on wheat crops showed the worst weed numbers (30–32 pcs/m2). During the autumn treatment with the herbicide Marathon, the number of productive stems was the largest: in the variety Mescal – 553 pcs/m2, and in the variety Palyanytsia – 560 pcs/m2. Reducing the weediness of winter wheat crops not only affected the number of productive stems, but also significantly improved grain quality., Главным условием выращивания озимой пшеницы является соблюдение правильной агротехники и создание условий высокой культуры земледелия. Совершенствование технологии в современных условиях производства зерна требует знания фенологических и морфологических особенностей растений, подбор адаптивных сортов, средств защиты культуры от вредоносных объектов, особенно сорняков и избежания негативного влияния на окружающую среду. Целью научных исследований было выявление эффективности осеннего и весеннего гербицидных обработок на урожайность и качество озимой пшеницы. Для данных исследований использовали сорта пшеницы - Мескаль и Паляныця. Нами установлено, что срок гербицидной обработки существенно влияет на засоренность посева, формирование урожая и качественные показатели зерна. Осенняя гербицидная обработка посевов озимой пшеницы препаратом Марафон, внесение одновременно с посевом 150 кг / га Диаммофоска и двукратная подкормка растений аммиачной селитрой способствует получению в условиях дерново-подзолистых супесчаных почв урожайности зерна сортов Мескаль и Паляныця на уровне 4,8-5,0 т / га. Нами выявлено, что на необработанных гербицидами участках количество сорняков увеличивалось от 80 до 130 шт / м2. Внесение гербицида Марафон (4 л / га) осенью обеспечило уменьшение количества сорняков в посевах озимой пшеницы с 86-90 шт / м2 до 8-10 шт / м2. Весеннее внесение этого гербицида было менее эффективным и показатели засоренности на этих участках уменьшались со 100-110 шт / м2 до 24-27 шт / м2. Весеннее применение гербицида Прима (0,5 л / га) на посевах пшеницы показало худшие показатели по количеству сорняков (30-32 шт / м2). При осенней обработке гербицидом Марафон количество продуктивных стеблей была такой: у сорта Мескаль - 553 шт / м2, а у сорта Паляныця - 560 шт / м2. Уменьшение засоренности посевов озимой пшеницы не только повлияло на количество продуктивных стеблей, но и значительно улучшило качество зерна.

Understanding the formation of star clusters with low star-formation efficiency (SFE) is very important to know about the star-formation history. In N-body models of star cluster evolution after gas expulsion, the Plummer model with outer power law density profile has been used massively. We study the impact of the density profile slopes on the survivability of the low-SFE star clusters after instantaneous gas expulsion. We compare cases when stellar cluster has Plummer profile and Dehnen profiles with cusp of different slopes at the time of formation. We determine the corresponding density profile of the residual gas for a given global SFE, assuming that our model clusters formed with a constant efficiency per free-fall time and hence have shallower density profile of gas than that of stars. We perform direct $N$-body simulations of evolution of clusters initially in virial equilibrium within gas potential after gas removal. We find that the violent relaxation lasts no longer than 20~Myr independently of the density profile power law slopes. Dehnen model clusters survive after violent relaxation with significantly lower SFEs when the global SFE measured within the Jacobi radius or within a half-mass radius. Dehnen $\gamma=0$ model clusters show similar final bound fraction with the Plummer model clusters if global SFE is measured within 10 scale radii. The final bound fraction increases with $\gamma$ values for a given global SFE. We conclude that Dehnen clusters better resist the consequences of the violent relaxation followed the instantaneous gas expulsion than the Plummer clusters. Thus the shallower the outer density slope of the low-SFE clusters, the better for their survivability after gas expulsion. Among Dehnen clusters we find that the steeper the inner slope (cusp) the higher the bound mass fraction is retained after violent relaxation for a given global SFE., Comment: 14 pages, 10 figures. Accepted for publication in Astronomy and Astrophysics (A&A)

Understanding the formation of star clusters with low star-formation efficiency (SFE) is very important to know about the star-formation history. In N-body models of star cluster evolution after gas expulsion, the Plummer model with outer power law density profile has been used massively. We study the impact of the density profile slopes on the survivability of the low-SFE star clusters after instantaneous gas expulsion. We compare cases when stellar cluster has Plummer profile and Dehnen profiles with cusp of different slopes at the time of formation. We determine the corresponding density profile of the residual gas for a given global SFE, assuming that our model clusters formed with a constant efficiency per free-fall time and hence have shallower density profile of gas than that of stars. We perform direct $N$-body simulations of evolution of clusters initially in virial equilibrium within gas potential after gas removal. We find that the violent relaxation lasts no longer than 20~Myr independently of the density profile power law slopes. Dehnen model clusters survive after violent relaxation with significantly lower SFEs when the global SFE measured within the Jacobi radius or within a half-mass radius. Dehnen $\gamma=0$ model clusters show similar final bound fraction with the Plummer model clusters if global SFE is measured within 10 scale radii. The final bound fraction increases with $\gamma$ values for a given global SFE. We conclude that Dehnen clusters better resist the consequences of the violent relaxation followed the instantaneous gas expulsion than the Plummer clusters. Thus the shallower the outer density slope of the low-SFE clusters, the better for their survivability after gas expulsion. Among Dehnen clusters we find that the steeper the inner slope (cusp) the higher the bound mass fraction is retained after violent relaxation for a given global SFE., Comment: 14 pages, 10 figures. Accepted for publication in Astronomy and Astrophysics (A&A)

We have developed the dynamical model of a clumpy torus in an active galactic nucleus (AGN) and compared to recent ALMA observations. We present $N$-body simulations of a torus in the field of a supermassive black hole (SMBH), made of up to $N=10^5$ gravitationally interacting clouds. As initial conditions, we choose random distributions of the orbital elements of the clouds with a cut-off in the inclination to mimic the presence of wind cones produced at the early AGN stage. When the torus reaches an equilibrium, it has a doughnut shape. We discuss the presence of box orbits. We have then constructed the velocity and velocity dispersion maps using the resulting distributions of the clouds at equilibrium. The effects of torus inclination and cloud sizes are duly analyzed. We discuss the obscuration effects of the clouds using a ray tracing simulation matching the model maps to ALMA resolution. By comparing the model with the observational maps of NGC 1068 we find that the SMBH mass is $M_\text{smbh}=5\times 10^6 M_\odot$ for the range of the torus inclination angles $45^\circ - 60^\circ$. We also construct the velocity dispersion maps for NGC 1326 and NGC 1672. They show that the peaks in the ALMA dispersion maps are related to the emission of the torus throat. Finally, we obtain the temperature distribution maps with parameters that correspond to our model velocity maps for NGC 1068. They show stratification in temperature distribution with the shape of the high temperature region as in the VLTI/MIDI map., Comment: 16 pages, 19 figures, 1 table, accepted for publication in MNRAS

© 2017, Pleiades Publishing, Ltd. The review describes the history of development of organic chemistry in higher schools of Russia over a period of 170 years, since the emergence of organic chemistry in our country till now.

© 2017, Pleiades Publishing, Ltd. The review describes the history of development of organic chemistry in higher schools of Russia over a period of 170 years, since the emergence of organic chemistry in our country till now.