The temperature fields in electrically heated wires at crisis of boiling

The self-organization processes take place in several phenomena and physical objects and in particular they arise in metals in conditions of charge transfer. At liquid helium temperature in conditions of the increase of direct current flowing through bismuth, indium and tungsten there arise unstabilities of charge carries flux and this process exhibits itself in electromagnetic oscillations generation. This instability the authors refer to the mutual influence of the current flowing through the sample and magnetic field of the current. With this heat flux density through the sample’s surfaces didn’t exceed 0.1 W/sm2. Such a value of heat flux is сlose to the first boiling crisis but the author state that the nature of these phenomena is no case is connected with the heat removal specific features

Optical transparency and local electronic structure of Yb-doped Y 2 O 3 ceramics with tetravalent additives

The results of optical transmission and X-ray core-level spectra measurements of Yb:Y 2 O 3 ceramics with different tetravalent sintering additives (ZrO 2 , CeO 2 and HfO 2 ) fabricated from nanopowders (produced by the laser ablation method) and then annealed at 1400 °C in air for 2 h are presented. It is found that the transmission values for ZrO 2 - and HfO 2 -doped ceramics at the lasing wavelengths are higher than those of CeO 2 -doped samples. The X-ray photoelectron spectra (XPS) O 1s spectra show that the relative intensity of oxygen defect peak detected for 3Yb:Y 2 O 3 + 5CeO 2 ceramics decreases substantially and consistently compared to that of 5Yb:Y 2 O 3 + 5HfO 2 and 3Yb:Y 2 O 3 + 5ZrO 2 samples. This can be attributed to a more complete filling of oxygen vacancies due to annealing-induced oxygen diffusion into the highly defective sintered ceramics. The measurements of XPS Ce 3d spectra showed that the insufficiently complete filling of the oxygen vacancies in the 3Yb:Y 2 O 3 + 5CeO 2 compound is due to the appreciable presence of trivalent cerium ions. © 2019 by the authors.Ministry of Education and Science of the Russian Federation, Minobrnauka: 3.7270.2017/8.9This study was supported by FASO (Theme "Electron" No. AAAA-A18-118020190098-5). The XPS measurements were supported by the Ministry of Education and Science of the Russian Federation (Project No. 3.7270.2017/8.9) and the Government of the Russian Federation (Act 211, agreement No. 02.A03.21.0006). Fabrication of ceramic samples was performed in the framework of the state task of IEP UB RAS

STRESS-PROTECTIVE AND ANTIOXIDANT EFFECT OF HUMULUS LUPULUS DRY EXTRACT AT CHRONIC EMOTIONAL STRESS

Stress-protective and antioxidant effects of Humulus lupulus dry extract were studied in experiments on white Wistar rats at prolonged emotional stress. It has been established that the H. lupulus dry extract had stress-protective effect, reducing the manifestation of degenerative catabolic changes in the internal organs of white rats in chronic emotional stress. The antistress activity of Humulus lupulus dry extract is caused by the pronounced antioxidant activity. On the background of the test extract introduction the MDA content decreased and the activity of catalase, SOD and the GSH content in the blood increased

The structure of Green functions in quantum field theory with a general state

In quantum field theory, the Green function is usually calculated as the expectation value of the time-ordered product of fields over the vacuum. In some cases, especially in degenerate systems, expectation values over general states are required. The corresponding Green functions are essentially more complex than in the vacuum, because they cannot be written in terms of standard Feynman diagrams. Here, a method is proposed to determine the structure of these Green functions and to derive nonperturbative equations for them. The main idea is to transform the cumulants describing correlations into interaction terms.Comment: 13 pages, 6 figure

МАТЕМАТИЧЕСКОЕ МОДЕЛИРОВАНИЕ ПЕРЕХОДНЫХ ПРОЦЕССОВ ТРЕХИМПУЛЬСНОЙ СИСТЕМЫ АВТОМАТИЧЕСКОГО РЕГУЛИРОВАНИЯ ПИТАНИЯ ВОДОЙ ПАРОГЕНЕРАТОРА НА СБРОС НАГРУЗКИ

The paper analyzes an operation of the standard three-impulse automatic control system (ACS) for steam generator water supply. Mathematical model for checking its operational ability on load relief has been developed in the paper and this model makes it possible to determine maximum deviations of water level without execution of actual tests and any corrections in the plants for starting-up of technological protection  systems in accordance with water level in the drum.  The paper reveals reasons of static regulation errors while solving problems of internal and external distortions caused by expenditure of over-heated steam in the standard automatic control system. An actual significance of modernization pertaining to automatic control system for steam generator water supply has been substantiated in the paper.Проанализирована работа типовой трехимпульсной системы автоматического регулирования (САР) питания водой парогенератора. Разработана математическая модель проверки ее работоспособности на сброс нагрузки, позволяющая устанавливать максимальные отклонения уровня воды без проведения натурных испытаний, без корректировки уставок срабатывания технологических защит по уровню воды в барабане. Определены причины статических ошибок регулирования при отработке внутренних и внешних возмущений по расходу перегретого пара в типовой САР. Обусловлена актуальность модернизации типовой САР питания водой парогенератора

Characterization of TiAlSiON coatings deposited by plasma enhanced magnetron sputtering: XRD, XPS, and DFT studies

The results of characterization of TiAlSiON hard coatings deposited on ferric-chromium AISI 430 stainless steel by plasma enhanced magnetron sputtering are presented. The coating with maximum hardness (of 43GPa) was obtained at the following optimal values of elemental concentrations: Si ~5at.%, Al ~15at.%, and Ti ~27at.%. The value of gaseous mixture (Ar-N2) pressure was of 0.13Pa and the value of partial pressure of oxygen (O2) was 1.3·10-3Pa. The X-ray diffraction (XRD) measurements showed the presence of Ti(Al)N. High-energy resolved XPS spectra of core levels revealed the formation of Ti-N, Ti-O-N, Si-N and Al-O-N bonds. Comparison of XPS valence band spectra with specially performed density functional theory calculations for disordered Ti0.5Al0.5N1-xOx (0≤x≤0.3) phases demonstrated that a Ti(Al)OxNy phase is formed on the surface of AISI430 steel upon the plasma enhanced magnetron sputtering, which can provide a good combination of high hardness and additional oxidation resistance of this material. © 2015 Elsevier B.V

Temperate bacteriophages collected by outer membrane vesicles in Komagataeibacter intermedius

The acetic acid bacteria have mainly relevance for bacterial cellulose production and fermented bio-products manufacture. The purpose of this study was to identify temperate bacteriophages in a cellulose-producing bacterial strain Komagataeibacter intermedius IMBG180. Prophages from K. intermedius IMBG180 were induced with mitomycin C and nalidixic acid. Transmission electron microscopy analysis exhibited tailed bacteriophages belonging to Myoviridae. A PCR assay targeting the capsid gene of the myoviruses proved phylogenetic position of induced phages. Nalidixic acid was poor inducer of prophages, however, it induced the OMV-like particles release. Size of OMVs depended on an antibiotic applied for phage induction and varied in the range of 30–80 and 120–200 nm. Inside some of them, tails of phages have been visible. Under conditions, inducing prophages, OMVs acted as the collectors of formed phage particles, using outer membrane receptors for phage detection (in this case, outer membrane siderophore receptor), and fulfilled therefore ―a cleaning,‖ as well as defensive functions, preventing bacteriophage spread outside population. This is the first description of myoviruses affiliated to K. intermedius, as well as outer membrane vesicles interaction with phages within this host.This research was supported by grant 47/2014 from National Academy of Sciences, Ukraine.http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1521-4028hb2016Biochemistr