17 research outputs found

    Tungstate Based Ceramics Obtained By Spark Plasma Sintering Method – Possible Material for Consolidation of Radioactive Wastes’ Components

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    The Spark Plasma Sintering method was used to produce high-density ceramics from tungstates SrWO4 and NaNd(WO4)2 with scheelite structure. These compounds are proposed as possible matrices for the consolidation of radwaste components. Powder samples were obtained by coprecipitation method and studied by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). After sintering, the samples retained their phase identity (scheelite structure). The total duration of sintering was ∼ 13-15 min, the relative density was reached ∼ 92, 99%. Keywords: Tungstates, RW, Spark Plasma Sintering, high density, microstructur

    Investigation of the microstructure of the fine-grained YPO4_4:Gd ceramics with xenotime structure after Xe irradiation

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    The paper reports on the preparation of xenotime-structured ceramics by the Spark Plasma Sintering (SPS) method. Phosphates Y0.95_{0.95}Gd0.05_{0.05}PO4_4 (YPO4_4:Gd) were obtained by the sol-gel method. The synthesized nanopowders are collected in large agglomerates 10-50 mkm in size. Ceramics has a fine-grained microstructure and a high relative density (98.67%). The total time of the SPS process was approximately 18 min. High-density sintered ceramics YPO4_4:Gd with a xenotime structure were irradiated with Xe+26^{+26} ions (E = 167 MeV) to fluences of 1×10121\times10^{12}-3×10133\times 10^{13} cm2^{-2}. Complete amorphization at maximum fluence was not achieved. As the fluence increases, an insignificant increase in the depth of the amorphous layer is observed. According to the results of grazing incidence XRD (GIXRD), with an increase in fluence from 1×10121\times10^{12}-3×10133\times 10^{13} cm2^{-2}, an increase in the volume fraction of the amorphous structure from 20 to 70% is observed. The intensity of XRD peak 200 YPO4_4:Gd after recovery annealing (700^\circC, 18 h) reached a value of ~80% of the initial intensity I0.Comment: 16 pages, 10 figure

    Напряженность иммунитета к кори в различных группах населения

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    Objective: to examine the state of the immunity to measles in different age groups.Materials and methods: In 2018, 4444 people were examined at the Diagnostic Center (virological). Among them, 3783 people were examined using the passive haemagglutination test for measles (manufactured by Pasteur Research Institute of Epidemiology and Microbiology, Russia). In the remaining 661 cases, the IgG to measles were detected using the enzyme-linked immunosorbent assay (ELISA) by VektoMeaseles IgG test (manufactured by Vector-Best, Russia). The correlation between the measles IgG level (ELISA) and the age was examined in 518 patients. Results: In this study, the immunity to measles was shown to be insufficient in all groups of observed people. Even among medical staff, nearly 10% had no protective level of measles antibodies. We have shown that the correlation between the measles IgG level and the age is statistically significant, so that the number of seronegative persons in different age groups differs significantly. Conclusion: The highest ratio of seronegative individuals was found in the age group between 18 and 25 years (52,33%), which can lead to serious measles outbreaks. Hence, this study confirms a strong need for additional immunization in all groups and especially in young population.Цель: изучить состояние иммунитета к кори в различных возрастных группах.Материалы и методы: В 2018 г. в Клинической инфекционной больнице им. С.П. Боткина в Городском консультативно-диагностическом центре (вирусологическом) было обследовано 4444 человека: у 3783 человек исследование было выполнено при помощи набора реагентов для реакции пассивной гемагглютинации к кори (производитель Научно-исследовательский институт эпидемиологии и микробиологии имени Пастера, Россия), в 661 случае был выполнен иммуноферментный анализ по определению IgG к вирусу кори с использованием тестсистемы «ВектоКорь IgG» (производитель АО «ВекторБест», Россия). Зависимость уровня антител к кори (метод иммуноферментного аналаиза) от возраста была исследована у 518 пациентов. Результаты: в данном исследовании было показано, что в настоящее время напряженность иммунитета во всех возрастных группах недостаточна. Даже среди медицинских работников был отмечен высокий процент серонегативных лиц. Показано наличие достоверной корреляции между уровнем IgG к кори и возрастом пациентов. Выявлены достоверные отличия по количеству серонегативных по кори лиц в различных возрастных группах. Заключение: значительное количество серонегативных лиц в возрастной группе до 25 лет создает серьезный риск возникновения эпидемии кори. Данное исследование показывает необходимость дополнительной иммунизации против кори всех групп населения и особенно лиц молодого возраста.

    CHARACTERISTICS OF SUPERCAPACITORS ELECTRODES BASED ON TITANIA AND CARBON NANOTUBES

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    TiO2-NT and CNT based electrodes have been fabricated by anodizing and pyrolysis and characterized by scanning electron microscope. Electrochemical performances such as spe-cific capacitance, energy and power have been calculated in frame of the galvanostatic charge-discharge curves analysis.Исследование выполнено в рамках инициативного научного проекта FEUZ-2020-0059 Минобрнауки РФ

    Аналіз методів та моделей оптимального розподілення навантажень між енергогенеруючими об’єтами

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    This paper gives consideration to the methods and models of the optimal distribution of loadings among energy generating facilities, in particular the method of dynamic programming; two-step method of the optimal distribution of loadings among the energy blocks using the so-called special reference points; methods and models in which the form of the fuzzy description of the factors of the data uncertainty is based on the theory of fuzzy sets; methods and models of the excess of versions; methods and models of relative increments in the fuel flow rate and their combinations; the heuristic method of the solution of the problem of the loading distribution using the limitations of the minimum and maximum electric loadings of energy blocks; the optimization method of the projection of the Rosen gradient, etc. Advantages and drawbacks of the methods and models were shown. It was shown that the methods and models used for the optimization of the distribution of loadings among energy generating facilities require improvement, which makes the development and improvement of the mathematical and algorithmic software used by the automated systems of the control of technological processes of the energy blocks of nuclear power stations and thermal power stations a vital problem.Рассмотрены методы и модели оптимального распределения нагрузок междуэнергогенерирующими объектами. Указаны достоинства и недостатки этих методов и моделей. Показананеобходимость совершенствования методов и моделей оптимизации распределения нагрузок междуэнергогенерирующими объектами, что делает актуальными разработки и усовершенствованиематематического и алгоритмического обеспечения, находящегося в распоряжении автоматизированныхсистем управления технологическими процессами энергоблоков АЭС и ТЭС.Розглянуто методи та моделі оптимального розподілу навантажень між енергогенеруючими об\'єктами. Вказані достоїнства і недоліки методів. Показано необхідність удосконалення методів і моделей оптимізації розподілу навантажень між енергогенеруючими об\'єктами, що робить актуальними розробки та удосконалення математичного та алгоритмічного забезпечення, яке знаходиться у розпорядженні автоматизованих систем управління технологічними процесами енергоблоків АЕС та ТЕС

    Measles immunity in different population groups

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    Objective: to examine the state of the immunity to measles in different age groups.Materials and methods: In 2018, 4444 people were examined at the Diagnostic Center (virological). Among them, 3783 people were examined using the passive haemagglutination test for measles (manufactured by Pasteur Research Institute of Epidemiology and Microbiology, Russia). In the remaining 661 cases, the IgG to measles were detected using the enzyme-linked immunosorbent assay (ELISA) by VektoMeaseles IgG test (manufactured by Vector-Best, Russia). The correlation between the measles IgG level (ELISA) and the age was examined in 518 patients. Results: In this study, the immunity to measles was shown to be insufficient in all groups of observed people. Even among medical staff, nearly 10% had no protective level of measles antibodies. We have shown that the correlation between the measles IgG level and the age is statistically significant, so that the number of seronegative persons in different age groups differs significantly. Conclusion: The highest ratio of seronegative individuals was found in the age group between 18 and 25 years (52,33%), which can lead to serious measles outbreaks. Hence, this study confirms a strong need for additional immunization in all groups and especially in young population

    A Technology for Isolation and Analysis of Lipophilic and Hydrophilic Biologically Active Components from <i>N. sativa</i> L. Seeds.

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    Introduction. Seeds of Nigella sativa L. are widely known as a source of fatty oil with a very rare component-thymoquinone. The therapeutic potential of biologically active compounds of plant seeds covers a positive effect on the gastrointestinal tract, cardiovascular and immune systems. In addition, hypoglycemic, antioxidant, antitumor, oncoprotective, immunomodulating effects were found in thymoquinone. In addition to fatty oil and thymoquinone, a number of other significant compounds are present in the seeds, which also make up their own pharmacological asset. Aim. Study was to develop a processing flow chart and analyze the lipophilic and hydrophilic components of the seeds of N. sativa L.Materials and methods. The following methods were used as analytical methods: gas-liquid chromatography with a flame ionization detector - for the analysis of sterols and triterpenes; chromatography-mass spectrometry (gas-liquid chromatography with mass spectrometric detection) - for the study of essential oil; chromatography-mass spectrometry (high performance liquid chromatography with mass spectrometric detection) - to study flavonoids. To obtain individual fractions of biologically active compounds of seeds of N. sativa L., fractional extraction was used.Results and discussion. The principle of this approach in this case is to extract the entire lipid complex of seeds with n-hexane, followed by removal of the extractant. The thickened hexane extract is treated with ethyl alcohol, which extracts unsaponifiable compounds - terpenes, quinones, sterols and does not dissolve triacylglycerides. The seed meal remaining after hexane extraction is treated with ethyl alcohol 70 %, into which hydrophilic molecules, in particular flavonoids, pass.Conclusion. After transesterification, 5 compounds were identified in the lipophilic fraction of saponifiable lipids, the linoleic and oleic acids being dominant. A characteristic feature of this fraction is the presence of cis-11,14-eicosadiene acid, which can act as a marker element of the fatty oil of the seeds of N. sativa L. Sterols and triterpenes were found in the unsaponifiable fraction. The major component of this fraction is β-sitosterol. In addition to the indicated sterol, campesterol and stigmasteri are present. Triterpenes are represented by cycloartenol and its derivatives. Simple phenols, quinones and monoterpenes were found in the essential oil complex, p-cymol, thymoquinone and α-thuyen predominate. The hydrophilic fraction of the seeds of N. sativa L. includes flavonoids of the methoxylated series of flavones and kempferol glycosides
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