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Тюпина, Екатерина Александровна

Организационные подразделения

Организационная единица

Цель ИЯФиТ и стратегия развития - создание и развитие научно-образовательного центра мирового уровня в области ядерной физики и технологий, радиационного материаловедения, физики элементарных частиц, астрофизики и космофизики.

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Тюпина

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Екатерина Александровна

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Теперь показываю 1 - 10 из 12

Только метаданные
Stability of modified technetium-containing magnesium potassium phosphate matrix under repository conditions with regard to biogeochemical effects
(2023) Abramova, E.; Safonov, A.; Popova N.; Tyupina, E.; Тюпина, Екатерина Александровна
Только метаданные
Magnetic Nanosorbents Based on Bentonite and CoFe2O4 Spinel
(2022) Khodosova, N.; Novikova, L.; Tomina, E.; Belchinskaya, L.; Tyupina, E. A.; Тюпина, Екатерина Александровна
New magnetic nanocomposite sorbents were obtained by doping natural bentonite with nanosized CoFe2O4 spinel (10 and 20 wt.%). Nanocrystals of cobalt ferrite were synthesized by a citrate burning method. The structure and physical-chemical properties of the composites were characterized by XRD, XRF, TEM, BET, FTIR and Faraday balance magnetometry. During the formation of nanocomposites, 10вЂ“30 nm particles of cobalt ferrite occupied mainly the interparticle space of Fe-aluminosilicate that significantly changed the particle morphology and composite porosity, but at the same time retained the structure of the 2:1 smectite layer. A combination of two functional properties of composites, adsorption and magnetism has been found. The adsorption capacity of magnetic nanosorbents exceeded this parameter for bentonite and spinel. Despite the decrease in the adsorption volume, pore size and specific surface area of the composite material relative to bentonite, the sorption activity of the composite increases by 12%, which indicated the influence of the magnetic component on the sorption process. FTIR data confirmed the mechanism of formaldehyde sorption by the composite sorbent. The production of a magnetic nanosorbent opens up new possibilities for controlling the sorption processes and makes it possible to selectively separate the sorbent from the adsorption medium by the action of a magnetic field.
Только метаданные
Sorption of137cs and90sr on organic sorbents
(2021) Belousov, P.; Semenkova, A.; Izosimova, Y.; Tolpeshta, I.; Tyupina, E.; Тюпина, Екатерина Александровна
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.The present study examines the sorption of Cs (I) and Sr (II) on organic sorbents in the pH range from 2 to 10, as well as the mechanisms of their binding. In order to determine the influence of the physical properties and the quantity of functional groups of the organic sorbents on sorption, experiments were carried out on organic materials of varying degrees of metamorphism: high-moor peat, hard and brown coals and shungite. A detailed description of their mineral composition, cation exchange capacity, buffering capacity and elemental composition of sorbents is provided. XRD, XRF, SEM and BET adsorption methods were used for assaying. As a result of the conducted research, it can be concluded that Sr (II) showed a higher sorption per unit specific surface area than Cs (I) in the studied range of concentrations and pH values. Sr (II) sorption decreases in the following order: high-moor peat > brown coal > shungite > hard coal. The sorption of Cs (I) is highest on brown coal and lesser for high-moor peat, shungite and hard coal. It is suggested that Cs (I) and Sr (II) can be fixed on carboxyl functional groups and Cs (I), possibly, in insignificant amounts on phenolic hydroxyls of all four studied organic sorbents.
Только метаданные
Synthesis, characterization, catalytic activity and adsorption properties of new nanosized cobalt-magnesium spinel ferrites for water treatment processes
(2025) Tomina, E. V.; Doroshenko, A. V.; Novikova, L. A.; Tyupina, E. A.; Kamzin, A. S.; Zhuzhukin, K. V.; Kopylov, A. V.; Тюпина, Екатерина Александровна
Открытый доступ
Cesium sorption and desorption on glauconite, bentonite, zeolite, and diatomite
(2019) Belousov, P.; Semenkova, A.; Egorova, T.; Romanchuk, A.; Tyupina, E.; Тюпина, Екатерина Александровна
© 2019, MDPI AG. All rights reserved.This study is devoted to studying the sorption of137Cs on mineral sorbents at a wide pH range, from 2 to 10, as well as to studying sorption mechanisms. In order to obtain the most reliable sorption characteristics, samples of high purity were examined as sorbents: bentonite, glauconite, zeolite, and diatomite. A detailed description of their mineral composition, cation exchange capacity and specific surface of sorbents is given. XRD, XRF, FTIR, SEM, and BET adsorption methods were used for assaying. The sorption and desorption values were identified for each sorbent. As a result of the conducted research, it can be concluded that137Cs sorption mainly occurs through the exchange reaction on zeolite, glauconite and bentonite. The highest cesium Kd was observed on zeolite due to its high CEC and amounted to 4.05 mg/L at pH 7. The higher sorption capacity of glauconite in comparison with bentonite is primarily due to the high layer charge which is mainly localized in tetrahedral sheets, and to the existence of highly selective sorption sites (frayed edge sites) on the glauconite surface. Diatomite showed the lowest sorption capacity provided by the presence of a small quantity of smectite and kaolinite in its composition. The values of desorption increase in the following order: zeolite < bentonite ~ diatomite < glauconite.
Только метаданные
Transformation of Structure and Adsorption Properties of Montmorillonite under Thermochemical Treatment
(2019) Krupskaya, V. V.; Zakusin, S. V.; Dorzhieva, O. V.; Chernov, M. S.; Tyupina, E. A.; Тюпина, Екатерина Александровна
© 2019, Pleiades Publishing, Ltd.Abstract—Complex studies revealed transformations of composition, structure, and properties of bentonite clays of the Taganskoe (Kazakhstan) and Dahskovskoe (Moscow oblast) deposits under thermochemical treatment. Leaching of cations from interlayer and octahedral sites, protonation of interlayer and OH-groups lead to the modification of interlayer and 2 : 1 layer composition. This, in turn, causes significant changes of properties: a decrease of cation exchange capacity owing to the decrease of layer charge and increase of specific surface through the decomposition and partial amorphization of structure. Bentonites of the Dashkovskoe deposit showed the higher resistance to the thermochemical impact than bentonites of the Taganskoe deposit owing to the isolating action of organic matter. Obtained results demonstrated that bentonite clays preserve most of adsorption properties even under such strong thermochemical influence (13 М HNO3, 90°С, 5 h).
Только метаданные
Effect of Characteristics of Magnesium Oxide Powder on Composition and Strength of Magnesium Potassium Phosphate Compound for Solidifying Radioactive Waste
(2019) Vinokurov, S. E.; Kulikova, S. A.; Krupskaya, V. V.; Tyupina, E. A.; Тюпина, Екатерина Александровна
© 2019, Pleiades Publishing, Ltd.Phase composition, particle morphology, and granulometric composition of commercial samples of MgO powders of various chemical purities (classification from technical grade to chemical grade) prepared by heat treatment at 1300°C for 3 h were studied for the subsequent synthesis of a compound based on magnesium potassium phosphate matrix MgKPO4·6H2O, promising for solidifying liquid radioactive waste. It has been established that to obtain a homogeneous mineral-like compound with compressive strength of about 15 MPa, which meets the regulatory requirements for solidified forms of liquid radioactive waste, it is necessary to use magnesium oxide powder with a particle size of not more than 50 μm, which have a high degree of crystallinity (the average crystallite size is not less than 40 nm). It was noted that the impurities of metal compounds, primarily silicon, calcium, and iron in the MgO powder, do not affect the synthesis conditions and the mechanical strength of the compound.
Открытый доступ
Conditioning of spent electrolyte surrogate LiCl-KCl-CSCl using magnesium potassium phosphate compound
(2020) Kulikova, S. A.; Belova, K. Yu.; Vinokurov, S. E.; Tyupina, E. A.; Тюпина, Екатерина Александровна
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).The current work was aimed at developing a new conditioning method of spent electrolyte-radioactive waste (RW) generated during the pyrochemical reprocessing of mixed nitride uranium-plutonium spent nuclear fuel. Magnesium potassium phosphate (MPP) compound samples were synthesized under solidification of the electrolyte surrogate solution in a LiCl-KCl-CsCl system. The phase composition and structure of obtained compounds were studied by XRD and SEM-EDS methods. It was found that the compounds possessed a high compressive strength of 17-26 MPa. Hydrolytic stability of the compounds was evaluated in accordance with the long semi-dynamic test GOST R 52126-2003 and with the static PCT test. The 137Cs content in the leached solutions was determined by gamma-ray spectrometry, and other compound components were determined by ICP-AES and ICP-MS methods. The differential leaching rate of Cs at 25 ◦C from monolithic samples on the 91st day of samples contact with water was 5-11 × 10−5 g/(cm2·day) (GOST R 52126-2003), and was 4-29 × 10−7 g/(cm2·day) on the 7th day at 90 ◦C from crushed samples (PCT). The thermal stability of the compound at 180 ◦C and 450 ◦C was shown. The characteristics of the obtained MPP compound correspond to the current regulatory requirements for materials for RW conditioning.
Только метаданные
Modification of the Cement Matrix with Organic Additives for Stabilizing Pertechnetate Ions
(2021) Kamorny, D. A.; Safonov, A. V.; Boldyrev, K. A.; Abramova, E. S.; Tyupina, E. A.; Тюпина, Екатерина Александровна
© 2021Stabilizing properties of polyhexamethyleneguanidine hydrochloride, tetraphelylphosphonium chloride, polyethyleneimine, and thiocarbamide were evaluated in order to determine their influence on the long-term stabilization of Tc in a Portland cement compound. The modifying agents’ effect on the mechanical strength under air-wet conditions was investigated. Possible impact of modifiers on the intensification of bacterial processes was taken into account during the investigation. A 2-5-fold reduction in pertechnetate leaching was observed when the investigated additives were applied. Addition of polyhexamethyleneguanidine hydrochloride was deemed preferable as it simultaneously ensured stabilization of Tc properties, provided the mechanical strength required, and protected the cement matrix from the biological degradation.
Только метаданные
The influence of acid modification on the structure of montmorillonites and surface properties of bentonites
(2019) Krupskaya, V.; Novikova, L.; Belousov, P.; Dorzhieva, O.; Tyupina, E.; Тюпина, Екатерина Александровна
© 2019 Elsevier B.V. Bentonites are often used as components of engineered barrier systems (EBS) for the radioactive waste disposal and isolation of hazardous nuclear facilities. In this paper, we consider possible transformations of the composition, structure and properties of bentonites when they are used as EBS components during the decommissioning of open pools with liquid radioactive waste (LRW). Operating conditions were modeled by the treatment with nitric acid at different durations (from 1 to 6 h), concentrations (from 1 to 8 M) and temperatures (20and 90°C). Nitric acid was chosen because it is used in the preparation procedure of LRW for isolation. To assess the intensity of transformations, bentonites with a high content of Al- and Fe-rich montmorillonites were selected. The work revealed effects of interlayer modification, leaching of octahedral cations, changes of the grain size distribution, specific surface area and weakening of surface basicity. It was also shown that temperature has a stronger effect on the structural transformation of montmorillonite than acid concentration and treatment duration. Formation of Al hydroxy-interlayered (HI) layers was observed due to the treatment with the nitric acid of lower concentration (1 M). The effect of a higher concentration at the same treatment duration and temperature leads to a more intensive leaching of Al from the octahedral sheets and protonation of the interlayer, which prevents the formation of Al hydroxy-interlayered (HI) layers. CO 2 desorption after the nitric acid treatment decreases significantly, maintaining a relatively high value only when the conditions allow the interlayer to be protonated. Modification of structural and adsorption characteristics due to the acid treatment can be used to simulate modification of the engineered barriers' properties for a long-term operation in the disposal of radioactive and toxic wastes.