2,152 research outputs found

    Chronopotentiometry at platinum electrode in KF-NaF-AlF3-Al2O3 melt

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    Some features of the mechanism of the anode process on platinum in KF–NaF–AlF3–Al2O3 melt at 750–780 °C depending on the of anodic current density (0.5 mA/cm2 to 2.0 A/cm2) and anodic pulse duration have been studied using chronopotentiometry method. In curves of change in the platinum anode potential a small peak at current densities of 10–30 mA/cm2 and a clear peak at current densities of 0.5–2.0 A/cm2 are recorded when the current is cut on. Analysis of dependencies of the transition time on the current density indicates that the first peak in curve is associated with the formation of an oxide compound on the platinum surface, and the second one is related to hindering the diffusion for delivery of electroactive particles to its surface.The study was supported by the Russian Foundation for Basic Research (grant № 13–03–00829 A)

    Анодный процесс на платине в расплаве на основе CaCl2-CaO

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    Methods potentiostatic polarization and cyclic voltammetry obtained new data on the mechanism and kinetics of anodic processes on platinum in the molten CaCl2-KCl-CaO when 725–775 °C. Given thermodynamic values of potential difference probable total reactions in the range of the studied temperature. Using potentiostatic polarization and cyclic voltammetry obtained new data on the mechanism and kinetics of anodic process on platinum in the molten CaCl2-KCl-CaO when 725–775 °C thermodynamic assessment of the probability of occurrence total reactions during electrolysis melt on the basis of CaCl2-CaO using non-carbon anode. It is shown that at high current densities anodic process takes place mainly in the conditions of slow diffusion of electrically active particles to the anode, and at low densities (up to 10 mA/cm2) to their discharge to the atomic and lecular oxygen is preceded by a stage, which can be associated with adsorption of atoms of oxygen or with the formation of an oxide film on the surface of platinum. To detect the nature of this stage, further research is needed.Методами потенциостатической поляризации и циклической вольтамперометрии получены новые экспериментальные данные о механизме и кинетике анодных процессов на платине в расплаве CaCl2-KCl-CaO при 725–775 °С. Приведены термодинамические значения разности потенциалов вероятных суммарных реакций в диапазоне исследуемых температур. При помощи потенциостатической поляризации и циклической вольтамперометрии получены новые экспериментальные данные относительно механизма и кинетики анодного процесса на платине в расплаве CaCl2-KCl-CaO при 725–775 °С. Проведены термодинамические оценки вероятности протекания суммарных реакций при электролизе расплава на основе CaCl2-CaO с использованием неуглеродного анода. Показано, что при высоких плотностях тока анодный процесс протекает преимущественно в условиях замедленной диффузии электроактивных частиц к аноду, а при низких плотностях (до 10 мА/см2) их разряду до атомарного и молекулярного кислорода предшествует стадия, которая может быть связана с адсорбцией атомов кислорода или с образованием оксидной пленки на поверхности платины. Для установления природы этой стадии необходимы дальнейшие исследования

    Investigation of the effect of nanosecond laser pulses processing on the microstructure and fatigue resistance of commercially pure titanium

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    The effect has been studied of treatment with nanosecond laser pulses on the fatigue resistance of plate samples of recrystallized (grain size of the order of 2-3 μm) commercially pure titanium (grade VT1-0) under cyclic tensile loading. The results of investigations by scanning and transmission electron microscopy of the subsurface layer microstructure of the alloy under study after exposure to nanosecond laser irradiation and subsequent fatigue tests are presente

    Возможности медикаментозного лечения синдрома обструктивного апноэ сна у детей

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    We have conducted a critical analysis of publications regarding the possibilities of medicamental treatment of obstructive sleep apnoea syndrome in children. Based on the examined studies we made a conclusion that intranasal glucocorticosteroids and leukotriene receptor antagonists can be effective in children with light and moderate lesions of this nature. At the same time, for the time being there isn’t enough published data to justify the recommendation of mentioned preparations as an alternative to surgery in children suffering from pulmonary ventilation stoppages. Further studies are required in order to determine the optimal terms of conservative treatment of obstructive sleep apnea in children, to determine the durability of the effect and ascertain the indications and contraindications for different groups of preparations.Проведен критический анализ публикаций, посвященных возможностям медикаментозного лечения синдрома обструктивного апноэ сна у детей. На основании изученного обзора исследований сделан вывод, что интраназальные глюкокортикостероиды и антагонисты лейкотриеновых рецепторов могут быть эффективны у детей с легкой и средней степенью тяжести такого нарушения. Тем не менее в настоящее время опубликованных данных для рекомендации указанных препаратов в качестве альтернативы хирургическому лечению у детей с остановкой легочной вентиляции во время сна пока недостаточно. Необходимы дальнейшие исследования по определению оптимальной длительности консервативного лечения синдрома обструктивного апноэ сна у детей, выяснению стойкости полученного эффекта, а также уточнению показаний и противопоказаний для различных групп препаратов

    Epizootiological and Epidemiological Situation on Tularemia in Russia in 2020, the Forecast for 2021

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    The purpose of the review is to assess the trends in the development of epizootic activity in various territories of the Russian Federation in order to identify the regions of increased risk of infection of the population with tularemia pathogen in 2021 and to plan and carry out high-priority measures in these regions, such as vaccination, investments in water, sanitation and hygiene infrastructure, epizootiological monitoring of natural foci and other measures aimed at suppressing the activity of natural foci and the development of herd immunity to this infection. In 2020, 41 cases of human infection with tularemia pathogen were registered on the territory of the Russian Federation, 60 % of which occurred in the Northwestern Federal District. Epizootic manifestations of the infection of varying intensity were detected in 55 constituent entities of Russia. Against this background, sporadic cases of tularemia in humans were registered in 14 regions of the country. The most pronounced epidemic complications continue in the territory of Karelia – 23 patients. 12 cultures of Francisella tularensis subsp. holarctica from the ambient environment were isolated in the Vologda (3), Rostov Regions (6), in the Khanty-Mansi Autonomous District (2), and in St. Petersburg (1). Based on the analysis of the data presented, in 2021, epidemic complications in the form of sporadic cases of the disease among the unvaccinated population in the following territories are most likely to occur: Central Federal District – in the Oryol, Ryazan and Yaroslavl Regions, as well as in Moscow; Northwestern Federal District – in the Arkhangelsk and Leningrad Regions, the Republic of Karelia and in St. Petersburg; Volga Federal District – in Tatarstan, Mordovia, Chuvash Republic, Kirov and Orenburg Regions; Ural Federal District – in the Khanty-Mansiysk, Yamalo-Nenets Autonomous Districts and the Tyumen Region; Siberian Federal District – in the Novosibirsk, Kemerovo, Tomsk and Omsk Regions, as well as in the Altai Territory; Far Eastern Federal District – in some regions of Kamchatka and Khabarovsk Territories

    Genetic Diversity of the Family <i>Francisellaceae</i>, Analysis of the situation on tularemia Incidence in the Russian Federation in 2021, and Forecast for 2022

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    The review briefly outlines the current taxonomy of the most studied strains of the species belonging to the family Francisellaceae. Due to the significant genetic diversity within the family, the detection of Francisella tularensis, especially in environmental samples, becomes even more difficult and may lead to false positive results. A comparison of the incidence rates in European countries, in which the extensive epidemic manifestations of tularemia are recorded annually, namely Sweden, Finland, Norway and the Czech Republic, and in Russia over the past five years is provided. The paper presents the comparative dynamics of tularemia incidence in the territories of the Federal Districts of the Russian Federation in recent years. The dynamics of the incidence during epidemic outbreaks in the Republic of Karelia and the Omsk Region over the past few years is shown. 17 cases of human infection with the causative agent of tularemia were registered on the territory of the Russian Federation in 2021. Epizootic manifestations of the infection of varying degrees of intensity were detected in 45 constituent entities of the Federation. Against that background, sporadic cases of tularemia in humans were reported in 11 regions of the country. Six cultures of Francisella tularensis subsp. mediasiatica from different types of ticks were isolated in the Krasnoyarsk Territory, the Republic of Altai and the Altai Territory. Based on the analysis of the data presented, in 2022, epidemic complications in the form of sporadic cases of the disease are most likely to occur among the unvaccinated population in the territories of the Central Federal District – the Voronezh, Ryazan, Smolensk Regions and in Moscow; Northwestern Federal District – in the Arkhangelsk Region, the Republic of Karelia and in St. Petersburg; Volga Federal District – in the territories of Samara, Kirov Regions and Republic of Tatarstan; Ural Federal District – in the Khanty-Mansiysk and Yamalo-Nenets Autonomous Districts; Siberian Federal District – in certain districts of the Kemerovo, Novosibirsk, Omsk and Tomsk Regions, Altai and Krasnoyarsk Territories

    Diagnostic Efficiency of Adsorbed Anthrax Vegetative Fluorescent Immunoglobulins Demonstrated in the Medical Trials

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    Studied is the diagnostic efficiency (specific activity, sensitivity, specificity, reproducibility) of anthrax vegetative fluorescent immunoglobulins. Based on the data, received in medical trials, this preparation is recommended for registration as a product for medical application in the Russian Federation

    EPIDEMIOLOGICAL AND EPIZOOTIOLOGICAL ANALYSIS OF THE SITUATION ON TULAREMIA IN THE RUSSIAN FEDERATION IN 2016 AND FORECAST FOR 2017

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    123 cases of human infection with Francisella tularensis were registered in the territory of the Russian Federation in 2016. 90 % of the total number was reported by three Federal Districts: North-Western, Siberian, and Central ones. Epizootic manifestations of varying intensity were detected in 56 regions. A considerable number of tularemia cases were observed in the Republic of Karelia, Nenets Autonomous District, Omsk and Ryazan Regions, and in Saint-Petersburg. Conspicuous are some recent peculiarities of tularemia manifestations: non-specificity of clinical symptoms, especially at early stages of the disease, their increasing variability against the background of mixed infections with tularemia and other natural-focal infections agents. The most expressed symptoms are fever and lymphatic adenitis; the patients are diagnosed with tularemia during initial days of the sought treatment in 40-45 % of the cases. Based on the data on morbidity rates in humans, epizootiological condition of natural tularemia foci, the numbers of isolated cultures and incidence of the vectors and carriers of the agent, as well as taking into consideration the scope of preventive vaccination in the regions, identified were the territories in which epidemic complication are most likely to occur in 2017

    Epizootic and Epidemic Situation on Tularemia in the Russian Federation in 2015 and Prognosis for 2016

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    Analyzed are the data on epizootiological and epidemiological surveillance of tularemia foci, situated in the territory of 85 constituent entities of the Russian Federation. Positive findings, obtained in the process of examination of small mammals, Ixodidae ticks, mosquitoes, and environmental objects, using immunological and molecular-genetic methods; isolated tularemia agent cultures; as well as tularemia incidence rates among the population have made provisions for the assessment of circulation and infection activity in the Regions. In period of 2015, 71 cases of human infection with tularemia have been registered. Given is a brief characteristics of activity of the natural tularemia foci and epidemic situation in the territory of the Russian Federation in 2015. Specified are the regions where preventive vaccination is on a low level. Given is the differentiation of RF territories according to the risk of exposure to tularemia infection for 2016
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