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

The use of atomic force microscopy for structural and surface morphological analysis of Fanconi anemia patient fibroblasts before and after exposure to γ-radiation

The surface morphological changes of Fanconi anemia patient fibroblasts after exposure to γ–radiation were investigated by AFM and foci immunofluorescence staining. The reorganization of the actin cytoskeleton was found, having resulted in reduction of the membrane stiffness and increase of adhesion in nuclear and lamellipodial regions of the cell

СТЕНД ДЛЯ ИССЛЕДОВАНИЯ ДИНАМИКИ ИЗМЕНЕНИЯ ТЕПЛОВЫХ ПОЛЕЙ В ИНФОРМАЦИОННО-КОММУНИКАЦИОННОЙ АППАРАТУРЕ ПРИ ОЦЕНКЕ ЗАЩИЩЕННОСТИ ИНФОРМАЦИИ

В работе представлена схема и принцип работы стенда, предназначенного для исследования динамики изменения тепловых полей в информационно-коммуникационной аппаратуре при оценке защищенности информации от утечек по физическим каналам связи. Предоставлены результаты апробации стенда при исследовании нагрева электронных компонентов на тестовой печатной плате, также показан результат воздействия провоцирующего электромагнитного сигнала на модуль с каналом связи IEEE 802.11g (Wi-Fi). Определены численные границы обнаружения нагрева электронных компонентов, представленные в виде минимальной подводимой мощности нагрева. Предложены мероприятия по снижению влияния на термографическое изображение рассеивающих свойств поверхностей проверяемых объектов, дрейфа температуры окружающей среды, высоких шумов изображения, а также инерционности тепловых процессов

The statement of the system “lipid peroxidation - antioxidants” of the patients with chronicle simple marginal gingivitis in the conditions of extreme climate

The aim of the investigation was to study free-radical oxidation and antioxidant protection of young persons with chronicle simple marginal gingivitis in the conditions of extreme climate. In patients with chronicle gingivitis there was revealed the misbalance in the system “Lipid peroxidation-antioxidant" resulting in biological membranes damage, in tissues breath lesion and parodontium vessels spasm.Целью исследования явилось изучение свободнорадикального окисления и антиоксидантной защиты у лиц молодого возраста с хроническим простым маргинальным гингивитом в условиях экстремального климата. У больных с хроническим гингивитом выявлен дисбаланс в системе «ПОЛ-антиоксиданты», что приводит к повреждению биологических мембран, нарушению тканевого дыхания и спазму сосудов пародонта

PHYSICOCHEMICAL CHARACTERIZATION OF RIBAVIRIN WITH SPECTROSCOPY AND MOLECULAR MODELING

This work was supported by Mendeleev University of Chemical Technology of Russia. Project Number K-003-2018

Low-Temperature Luminescence of Lead Silicate Glass

The temperature quenching of intrinsic luminescence of a lead silicate glass of the 20PbO · 80SiO2 composition has been investigated in the temperature range 7-200 K. It has been found that the temperature behavior of the intensity of intrinsic luminescence does not obey the well-known Mott's law for intracenter quenching of luminescence but is adequately described by the empirical Street's formula. It has been dem-onstrated that, with allowance made for the disorder of the atomic structure, the experimental temperature dependence of the luminescence intensity of the glass can be represented as a superposition of Mott's depen-dences for an ensemble of local luminescence centers. The obtained distribution of luminescence centers over the activation energies of quenching has an asymmetric form with prevailing low-energy states. It has been assumed that this feature has a general character and, at low temperatures, determines the specificity of the processes of nonradiative relaxation of the electronic subsystem for many oxide glasses. © Pleiades Publishing, Ltd., 2010.This study was supported by the Russian Foundation for Basic Research (project nos. 09-02-00493 and 08-02-01072)

РЕСУРСО- И ЭКОЛОГОСБЕРЕГАЮЩИЕ ТЕХНОЛОГИИ ПРОИЗВОДСТВА ВТОРИЧНЫХ АЛЮМИНИЕВЫХ СПЛАВОВ

The main directions of resource-saving and environment-saving technologies of fabrication of secondary aluminum alloys in modern industrial conditions are considered. The types of feedstocks and applied smelting aggregates are analyzed, and promising ways of the further improvement of this production process are shown. It is revealed that the traditional method of processing secondary aluminum feedstock, which is widely used in practice, is the thermal treatment in the medium of molten chloride salts. Salt-free technologies of processing aluminum dross, which are based on separation of metal and oxides by mechanical effect on them in conditions of high temperatures in the medium of the furnace atmosphere or collector metal, are proposed. Their advantages compared with a widespread salt technology are considered: materials applied to treat the melt are substantially lower-cost than alkali metal chlorides; dump slags are environmentally pure; the process has high productivity since it is performed in one metallurgical aggregate, which excludes the necessity to perform operations of cleaning the walls and bottom part in it. The examples of implementation of considered salt-free technologies of processing aluminum feedstock in conditions of several Russian metallurgical enterprises are shown.Рассмотрены основные направления ресурсо- и экологосберегающих технологий получения вторичных алюминиевых сплавов в современных производственных условиях. Проведен анализ видов сырья и применяемых плавильных агрегатов, показаны перспективные пути дальнейшего совершенствования данного производственного процесса. Выявлено, что традиционным промышленным способом переработки вторичного алюминиевого сырья, широко используемым на практике, является термическая обработка в среде расплавленных смесей хлоридов. Предложены бессолевые технологии переработки алюминиевых шлаков, основанные на разделении металла и оксидов путем механического воздействия на них в условиях высоких температур в среде печной атмосферы или металла-коллектора. Рассмотрены их преимущества по сравнению с широко распространенной солевой технологией: материалы, применяемые для обработки расплава, существенно дешевле хлоридов щелочных металлов; отвальные шлаки являются экологически чистыми; процесс имеет высокую производительность, так как осуществляется в одном металлургическом агрегате, что исключает необходимость проведения в нем операции чистки стенок и донной части. Показаны примеры реализации рассмотренных бессолевых технологий переработки алюминиевого сырья в условиях нескольких российских металлургических предприятий