Is KPD 1930+2752 a good SN Ia progenitor?

We investigate the evolution of a binary system which initially has an orbital period of 2^h 17^m and contains a 0.5 M_sun helium star with a white dwarf companion of 0.97 M_sun, similarly to suggested SN Ia candidate progenitor KPD 1930+2752. We show that the helium star completes core helium burning and becomes a white dwarf before components merge. The most probable outcome of the merger of components is formation of a massive white dwarf, despite initially the total mass of the system is above the Chandrasekhar mass

The mathematical model of the law on the correlation of unique competencies with the emergence of new consumer markets

The article deals with the applied aspects of assessing the influence degree of unique competencies on the process of creating innovative technologies and forming new consumer markets. It also builds the economic model, which demonstrates the presence of this correlation. Paper formulates the law on spiral dependence of the competences level on the emergence of new markets. The authors proposed mathematical instruments based on simulation modeling, which confirms the objectivity of the derived law.peer-reviewe

Low-temperature synthesis under low oxygen pressure and thermodynamic properties of YbFe2O4–δ

Received: 27.11.2017. Accepted: 26.03.2018. Published: 10.05.2018.The mixed-valence compound YbFe2O4–δ was synthesized using a modified method that allows employing gaseous atmosphere with a controlled ratio of inert gas and oxygen. The stability range for YbFe2O4–δ was determined at 1090 °C under reducing conditions. Thermodynamic characteristics for the formation of YbFe2O4–δ from the simple oxides and from elements in the temperature range 700–910 °C have been calculated. The obtained results allow specifying the low-temperature part of P-T-X diagram for the Yb-Fe-O system.The study was done in accordance with the state quota for IMET UB RAS, theme No. 0396-2015-0075, using equipment of CCU “Ural-M”

EDUCATIONAL TECHNOLOGY - THE CHAMPIONSHIP «MEDICAL SOFT SKILLS»

Статья посвящена формированию «гибких» навыков (softskills) обучающихся в процессе медицинского образования. Рассмотрена роль Чемпионата «Medicalsoftskills» в обучении специалистов для сферы здравоохраненияThe article is devoted to the formation of soft skills of students in the process of medical education. The role of the “Medical soft skills” Championship in the training of specialists for the healthcare sector is considere

Non-conservative Evolution of Cataclysmic Variables

We suggest a new mechanism to account for the loss of angular momentum in binaries with non-conservative mass exchange. It is shown that in some cases the loss of matter can result in increase of the orbital angular momentum of a binary. If included into consideration in evolutionary calculations, this mechanism appreciably extends the range of mass ratios of components for which mass exchange in binaries is stable. It becomes possible to explain the existence of some observed cataclysmic binaries with high donor/accretor mass ratio, which was prohibited in conservative evolution models.Comment: LaTeX, 32 pages, to be published in Astron. Z

Effects of nanodispersed iron on the morphofunctional parameters of the blood system

The effects of nanodispersed iron forms on the morphology and function of the blood system were studied. Maghemite and lepidocrocite caused a leukocytic shift towards segmented neutrophil forms, reduction of lymphocyte rigidity, and stimulated their compactization. In addition, the counts of small hyperchromatic erythrocytes with high rigidity increased in the blood flow. The results indicated that a single dose of nanodispersed iron-containing drugs improved the blood respiratory function and its microrheolog

Influence of temperature and oxygen pressure on the stability of barium or strontium doped neodymium manganites

In this work neodymium manganites, Nd1-xAxMnO3±δ, doped with Ba or Sr (where x = 0.15 and 0.25) were obtained by ceramic technology at 1250 °C. In order to obtain materials with stable thermal and electrical properties, their structure and physicochemical properties were studied depending on the dopant type and its concentration. It was established that the manganites doped with strontium (for x = 0.15 and 0.25) and barium (for x = 0.15) have the Jahn-Teller distortion of the structure, but it was not observed for the sample Nd0.75A0.25MnO3±δ. The sequence of phase transformations was studied under conditions of reduced oxygen pressure in gaseous phase using thermal analysis in combination with XRD. The influence of temperature and oxygen pressure on the stability limit of the manganites was investigated. The studied manganites remain stable in the range of partial oxygen pressures PO2 from 0.21 to 10−14 atm at 800 °C. An increasing in the dopant concentration leads to the increase of manganite electrical conductivity without decreasing the thermal stability limit. © 2020 University of Novi Sad, Faculty of Technology. All rights reserved