Главная
Авторизация
Фамилия
Пароль
 

Базы данных


Труды сотрудников ИФ СО РАН - результаты поиска

Вид поиска

Область поиска
в найденном
Формат представления найденных документов:
полныйинформационныйкраткий
Отсортировать найденные документы по:
авторузаглавиюгоду изданиятипу документа
Поисковый запрос: (<.>K=Ferrihydrite<.>)
Общее количество найденных документов : 69
Показаны документы с 1 по 20
1.


   
    Magnetic collective state formation upon tuning the interparticle interactions in ensembles of ultrafine ferrihydrite nanoparticles / D. A. Balaev, A. A. Krasikov, Yu. V. Knyazev [et al.] // Nano-Struct. Nano-Objects. - 2024. - Vol. 37. - Ст. 101089, DOI 10.1016/j.nanoso.2023.101089. - Cited References: 93. - The authors thank M.N. Volochaev for the TEM investigations . - ISSN 2352-507X. - ISSN 2352-5088
Кл.слова (ненормированные):
Nanoparticle coating -- Superspin-glass state -- Superparamagnetic blocking -- Surface spin subsystem
Аннотация: The results of a study of the dynamic (alternating current magnetic susceptibility) and static magnetic properties, as well as 57Fe Mössbauer spectrometry and ferromagnetic resonance of two-line ferrihydrite nanoparticle systems with varying intensities of magnetic interparticle interactions are reported. The strength of the magnetic interparticle interactions has been tuned by coating (with various degrees of coating) the ferrihydrite particles (2–4 nm in size and an average size ∼2.7 nm) of the initial synthetic sample by arabinogalactan. Also, a biogenic ferrihydrite sample (an average particle size of 2-nm) with a natural organic coating was studied and it has the weakest magnetic interparticle interactions among of all the samples. Relaxation times of the particle’s magnetic moment were determined by the data of static and dynamic magnetic susceptibilities and from analysis of 57Fe Mössbauer spectrometry. Based on the temperature dependences of the relaxation times, it has been concluded that the predominantly collective processes of freezing of the particle magnetic moments occur under the action of the magnetic interparticle interactions. It is shown that an important role in these processes is played by a magnetic subsystem of the surface spins of the particles. The effect of the interplay between the surface spin and magnetic moment subsystems on the static magnetic properties (low-temperature magnetic hysteresis loops) and the parameters of the microwave absorption line under the magnetic resonance conditions is discussed.

Смотреть статью,
Scopus,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk 660036, Russia
Federal Research Center KSC SB RAS, Krasnoyarsk 660036, Russia
Institute of Chemistry and Chemical Technology, Federal Research Center KSC SB RAS, Krasnoyarsk 660036, Russia

Доп.точки доступа:
Balaev, D. A.; Балаев, Дмитрий Александрович; Krasikov, A. A.; Красиков, Александр Александрович; Knyazev, Yu. V.; Князев, Юрий Владимирович; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Mikhlin, Yu. L.; Volochaev, M. N.; Волочаев, Михаил Николаевич; Bayukov, O. A.; Баюков, Олег Артемьевич; Ladygina, V. P.; Stolyar, S. V.; Столяр, Сергей Викторович; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
2.


   
    Separating the contributions of the magnetic subsystems in antiferromagnetic ferrihydrite nanoparticles by analyzing the magnetization in fields of up to 250 kOe / A. A. Krasikov, D. A. Balaev, A. D. Balaev [et al.] // J. Magn. Magn. Mater. - 2024. - Vol. 592. - Ст. 171781, DOI 10.1016/j.jmmm.2024.171781. - Cited References: 84. - This study was supported by his work was supported by the Russian Science Foundation, project no. 22–72-00134. - Authors thank to D.A. Velikanov, S.V. Komogortsev for fruitful discussions . - ISSN 0304-8853. - ISSN 1873-4766
Аннотация: Contributions of different magnetic subsystems formed in the systems of synthetic ferrihydrite nanoparticles (characterized previously) with an average size of ˂d˃ ≈ 2.7 nm coated with polysaccharide arabinogalactan in different degrees have been separated by measuring the dependences of their magnetization M on magnetic field H of up to 250 kOe on vibrating sample and pulsed magnetometers. The use of a wide measuring magnetic field range has been dictated by the ambiguity in identifying a linear M(H) portion for such antiferromagnetic nanoparticle systems within the conventional field range of 60–90 kOe. The thorough analysis of the magnetization curves in the temperature range of 100–250 K has allowed the verification of the contributions of (i) uncompensated magnetic moments µun in the superparamagnetic subsystem, (ii) the subsystem of surface spins with the paramagnetic behavior, and (iii) the antiferromagnetic susceptibility of the antiferromagnetically ordered ferrihydrite particle core. As a result, a model of the magnetic state of ferrihydrite nanoparticles has been proposed and the numbers of spins corresponding to magnetic subsystems (i)–(iii) have been estimated. An average magnetic moment μun of ∼ 145 μB (μB is the Bohr magneton) per particle corresponds approximately to 30 decompensated spins of iron atoms in a particle (about 3 % of all iron atoms), which, according to the Néel’s hypothesis μun ∼ ˂d˃3/2, are localized both on the surface and in the bulk of an antiferromagnetically ordered particle. The fraction of free (paramagnetic) spins is minimal in the sample without arabinogalactan coating of the nanoparticle surface (7 %) and is attained 20 % of all iron atoms in the sample with the highest degree of spatial separation of particles. According to this estimation, paramagnetic spins are located mainly on the edges and protruding areas of particles. Most magnetic moments of iron atoms are ordered antiferromagnetically and the corresponding magnetic susceptibility of this subsystem behaves as in an antiferromagnet with the randomly distributed crystallographic axes, i.e., increases with temperature.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics, Federal Research Center of Siberian Branch of Russian Academy of Sciences, Krasnoyarsk, Russia
Federal Research Center of Siberian Branch of Russian Academy of Sciences Krasnoyarsk, Russia

Доп.точки доступа:
Krasikov, A. A.; Красиков, Александр Александрович; Balaev, D. A.; Балаев, Дмитрий Александрович; Balaev, A. D.; Балаев, Александр Дмитриевич; Stolyar, S. V.; Столяр, Сергей Викторович; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
3.


   
    Studying the ferromagnetic resonance heating of an isotropic superparamagnet by the example of biogenic ferrihydrite nanoparticles / S. V. Stolyar, O. A. Li, A. M. Vorotynov [et al.] // Bull. Russ. Acad. Sci.: Phys. - 2024. - Vol. 88, Is. 4. - P. 536-539, DOI 10.1134/S106287382370627X. - Cited References: 10 . - ISSN 1062-8738. - ISSN 1934-9432
Аннотация: Ferrihydrite nanoparticles are synthesized and characterized. The dependences of heating of powders are studied upon pumping by a high-frequency electromagnetic field on a dc magnetic field. It is shown that the experimental dependence of the temperature of particles on a dc magnetic field is consistent with the theory of ferromagnetic resonance for an isotropic superparamagnet.

Смотреть статью,
Читать в сети ИФ
Держатели документа:
Federal Research Center “Krasnoyarsk Science Center,” Siberian Branch, Russian Academy of Sciences, 660036, Krasnoyarsk, Russia
Siberian Federal University, 660041, Krasnoyarsk, Russia
Kirensky Institute of Physics, Federal Research Center “Krasnoyarsk Science Center,” Siberian Branch, Russian Academy of Sciences, 660036, Krasnoyarsk, Russia

Доп.точки доступа:
Stolyar, S. V.; Столяр, Сергей Викторович; Li, O. A.; Vorotynov, A. M.; Воротынов, Александр Михайлович; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Maksimov, N. G.; Iskhakov, R. S.; Исхаков, Рауф Садыкович; Ladygina, V. P.; Shokhrina, A. O.
}
Найти похожие
4.


   
    Interparticle magnetic interactions and magnetic field dependence of superparamagnetic blocking temperature in ferrihydrite nanoparticle powder systems / A. A. Krasikov, Yu. V. Knyazev, D. A. Balaev [et al.] // Phys. B: Condens. Matter. - 2023. - Vol. 660. - Ст. 414901, DOI 10.1016/j.physb.2023.414901. - Cited References: 66. - This study was supported by his work was supported by the Russian Science Foundation, project no. 22-72-00134 . - ISSN 0921-4526. - ISSN 1873-2135
Кл.слова (ненормированные):
Ferrihydrite nanoparticles -- Interparticle magnetic interactions -- Superparamagnetic blocking temperature -- Coating -- Arabinogalactan
Аннотация: In this study, nanoparticles of initial synthetic ferrihydrite have been coated with arabinogalactan. The synthesized series of samples with different degrees of coverage of particles has been characterized by X-ray photoelectron spectroscopy, Mossbauer spectroscopy, transmission electron microscopy and magnetometry. The superparamagnetic blocking temperature decreases monotonically with an increase in the degree of coverage of ferrihydrite particles, which is unambiguously related to the different role of the interparticle magnetic interactions in the investigated powder systems. Analysis of the field dependence of the blocking temperature within the random anisotropy model has shown that an increase in the degree of coverage of ferrihydrite particles leads to a decrease in the size of a cluster in which the behaviors of the nanoparticle magnetic moments are correlated. The results obtained have shown the possibility of effective control of the strength of magnetic interparticle interactions in powder ferrihydrite systems by coating nanoparticles with arabinogalactan.

Смотреть статью,
WOS,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk, 660036 Russia
Siberian Federal University, Krasnoyarsk, 660041, Russia
Krasnoyarsk Scientific Center, Federal Research Center KSC SB RAS, Krasnoyarsk, 660036, Russia
Institute of Chemistry and Chemical Technology, Federal Research Center KSC SB RAS, Krasnoyarsk, 660036 Russia

Доп.точки доступа:
Krasikov, A. A.; Красиков, Александр Александрович; Knyazev, Yu. V.; Князев, Юрий Владимирович; Balaev, D. A.; Балаев, Дмитрий Александрович; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Stolyar, S. V.; Столяр, Сергей Викторович; Mikhlin, Yu. L.; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
5.


   
    Spin dynamics in ensembles of ultrafine ferrihydrite nanoparticles / Yu. V. Knyazev, D. A. Balaev, S. A. Skorobogatov [et al.] // Phys. Rev. B. - 2023. - Vol. 107, Is. 11. - Ст. 115413, DOI 10.1103/PhysRevB.107.115413. - Cited References: 66. - The electron microscopy study and ac susceptibility measurements were carried out on the equipment of the Krasnoyarsk Territorial Center for Collective Use, Krasnoyarsk Scientific Center, Siberian Branch of the Russian Academy of Sciences. This study was supported by the Russian Science Foundation, Project No. 21-72-00025 Tuning the Magnetic Properties of Ultrafine Biocompatible Ferrihydrite Nanoparticles through Interparticle Interactions [66] . - ISSN 2469-9950. - ISSN 2469-9969
Аннотация: Features of the spin dynamics in ensembles of interacting (FH-chem) and weakly interacting (FH-coated) magnetic ultrasmall (‹d› ∼ 2 nm) ferrihydrite nanoparticles have been explored. The dc and ac magnetic susceptibilities [χ'(T ) and χ''(T )] of the investigated samples have been thoroughly measured in a weak magnetic field (2 Oe) around the temperatures of superparamagnetic blocking of the nanoparticle magnetic moments (19 and 50.4 K for FH-coated and FH-chem, respectively, according to the dc magnetization data). It has been shown that the magnetic interactions between nanoparticles induce the formation of the cluster spin-glass state below the superparamagnetic blocking temperature (Tg = 18 and 49.5 K for FH-coated and FH-chem, respectively). It has been found that coating of nanoparticles increases the critical scaling index from zν = 5.9 (FH-chem) to zν = 8.0 (FH-coated). This indicates a general slowdown of the dynamics of correlated spins, which is also expressed as an increase in relaxation time τ0 after switching on the interparticle interactions. We attribute this phenomenon to a consequence of a change in the volume of correlated spins with the increasing size of a cluster of interacting nanoparticles. It has been demonstrated using the simulated χ''(T ) dependence that the dissipation of the magnetic energy occurs in two independent stages. The first stage is directly related to the blocking of the nanoparticle magnetic moments, while the second stage reflects the spin-glass behavior of surface spins and depends strongly on the intensity of the interparticle interactions.

Смотреть статью,
Смотреть статью,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Akademgorodok 50, bld. 38, Krasnoyarsk 660036, Russia
Siberian Federal University, Svobodniy 79, Krasnoyarsk 660041, Russia

Доп.точки доступа:
Knyazev, Yu. V.; Князев, Юрий Владимирович; Balaev, D. A.; Балаев, Дмитрий Александрович; Skorobogatov, S. A.; Скоробогатов, Станислав Алексеевич; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Bayukov, O. A.; Баюков, Олег Артемьевич; Stolyar, S. V.; Столяр, Сергей Викторович; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
6.


   
    Magnetic interparticle interactions and superparamagnetic blocking of powder systems of biogenic ferrihydrite nanoparticles / A. A. Krasikov, Yu. V. Knyazev, D. A. Balaev [et al.] // J. Exp. Theor. Phys. - 2023. - Vol. 137, Is. 6. - P. 903-913, DOI 10.1134/S1063776123120075. - Cited References: 58. - This study was supported by the Russian Science Foundation, project no. 22-72-00134 . - ISSN 1063-7761. - ISSN 1090-6509
Аннотация: The magnetic-field dependence of the superparamagnetic-blocking temperature TB of systems of antiferromagnetically ordered ferrihydrite nanoparticles has been investigated and analyzed. We studied two powder systems of nanoparticles: particles of “biogenic” ferrihydrite (with an average size of 2.7 nm), released as a result of vital functions of bacteria and coated with a thin organic shell, and particles of biogenic ferrihydrite subjected to low-temperature annealing, which cause an increase in the average particle size (to 3.8 nm) and burning out of the organic shell. The character of the temperature dependences of magnetization, measured after cooling in a weak field, as well as the shape of the obtained dependences TB(H), demonstrate peculiar features, indicating the influence of magnetic interparticle interactions. A detailed analysis of the dependences TB(H) within the random magnetic anisotropy model made it possible to estimate quantitatively the intensity of magnetic particle–particle interactions and determine the magnetic anisotropy constants of individual ferrihydrite particles.

Смотреть статью,
Scopus,
Читать в сети ИФ

Публикация на русском языке Магнитные межчастичные взаимодействия и суперпарамагнитная блокировка порошковых систем наночастиц биогенного ферригидрита [Текст] / А. А. Красиков, Ю. В. Князев, Д. А. Балаев [и др.]. - 13 с. // Журн. эксперим. и теор. физ. - 2023. - Т. 164 Вып. 6. - С. 1026-1038

Держатели документа:
Kirensky Institute of Physics, Siberian Branch, Russian Academy of Sciences, 660036, Akademgorodok, Krasnoyarsk, Russia
Federal Research Center “Krasnoyarsk Science Center of the Siberian Branch of the Russian Academy of Sciences”, 660036, Krasnoyarsk, Russia

Доп.точки доступа:
Krasikov, A. A.; Красиков, Александр Александрович; Knyazev, Yu. V.; Князев, Юрий Владимирович; Balaev, D. A.; Балаев, Дмитрий Александрович; Stolyar, S. V.; Столяр, Сергей Викторович; Ladygina, V. P.; Balaev, A. D.; Балаев, Александр Дмитриевич; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
7.


   
    Superparamagnetic relaxation in ensembles og ultrasmall ferrihydrite nanoparticles / D. A. Balaev, S. A. Skorobogatov, D. A. Velikanov [et al.] // Магнитные материалы. Новые технологии : тез. докл. IX Байкал. междунар. конф. BICMM-2023 / чл. прогр. ком.: S. S. Aplesnin [et al.] ; чл. орг. ком. R. S. Iskhakov [et al.]. - Иркутск, 2023. - P. 92. - Библиогр.: 1 . - ISBN 978-5-962402178-0
   Перевод заглавия: Спиновая динамика в ансамблях ультрамалых ферричастиц ферригидрита

Материалы конференции,
Материалы конференции,
Читать в сети ИФ
Держатели документа:
Сибирский федеральный университет
Институт физики им. Л. В. Киренского СО РАН

Доп.точки доступа:
Аплеснин, Сергей Степанович \чл. прогр. ком.\; Aplesnin, S. S.; Балаев, Дмитрий Александрович \чл. прогр. ком.\; Balaev, D. A.; Овчинников, Сергей Геннадьевич \чл. прогр. ком.\; Ovchinnikov, S. G.; Исхаков, Рауф Садыкович \чл. орг. ком.\; Iskhakov, R. S.; Балаев, Дмитрий Александрович; Skorobogatov, S. A.; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Bayukov, O. A.; Баюков, Олег Артемьевич; Stolyar, S. V.; Столяр, Сергей Викторович; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Исхаков, Рауф Садыкович; Knyazev, Yu. V.; Князев, Юрий Владимирович; Байкальская международная конференция "Магнитные материалы. Новые технологии"(9 ; 2023 ; сент. ; 11-14 ; Байкальск); "Магнитные материалы. Новые технологии", Байкальская международная конференция(9 ; 2023 ; сент. ; 11-14 ; Байкальск); "Magnetic materials. New tecnologies", Baikal International Conference(9 ; 2023 ; Sept. ; 11-14 ; Baikalsk); Иркутский государственный университет
}
Найти похожие
8.


   
    Role of the surface effects and interparticle magnetic interactions in the temperature evolution of magnetic resonance spectra of ferrihydrite nanoparticle ensembles / D. A. Balaev, S. V. Stolyar, Y. V. Knyazev [et al.] // Results Phys. - 2022. - Vol. 35. - Ст. 105340, DOI 10.1016/j.rinp.2022.105340. - Cited References: 119. - Authors thank to A.D. Balaev, S.V. Komogortsev for fruitful discussions and M.N. Volochaev for TEM studies. The TEM study and measurements of X-band FMR spectra were carried out on the equipment of the Krasnoyarsk Territorial Center for Collective Use, Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences. This study was supported by the Russian Science Foundation, project no. 21-72-00025 (https://rscf.ru/project/21-72-00025/) "Tuning the Magnetic Properties of Ultrafine Biocompatible Ferrihydrite Nanoparticles through Interparticle Interactions" . - ISSN 2211-3797
Кл.слова (ненормированные):
Ferrihydrite nanoparticles -- Superparamagnetism -- Interparticle magnetic interactions -- Ferromagnetic resonance
Аннотация: Ferrihydrite is characterized by the antiferromagnetic ordering and, in ferrihydrite nanoparticles, as in nanoparticles of any antiferromagnetic material, an uncompensated magnetic moment is formed. We report on the investigations of ferrihydrite powder systems with an average particle size of ∼ 2.5 nm obtained (i) as a product of the vital activity of bacteria (sample FH-bact) and (ii) by a chemical method (sample FH-chem). In the first approximation, these samples can be considered to be identical. However, in sample FH-chem, particles contact directly, while in sample FH-bact, they have organic shells; therefore, the interparticle magnetic interactions in these samples have different degrees. The main goal of this work has been to establish the effects of the interparticle magnetic interactions and individual characteristics of ferrihydrite nanoparticles on ferromagnetic resonance (FMR) spectra. The FMR spectra have been measured at different (9.4–75 GHz) frequencies in a wide temperature range. It has been found that, at low temperatures, the field-frequency dependence ν(HR) of the investigated systems has a gap ν/γ = HR + HA, where HR is the resonance field and HA is the induced anisotropy, which decreases with increasing temperature. To estimate a degree of the effect of interparticle interactions on the results obtained and to correctly determine the temperature range of the superparamagnetic (or blocked) state, the static magnetic measurement and Mössbauer spectroscopy data have been obtained and analyzed. It has been shown that the most striking feature of the FMR spectra - a gap in the field-frequency dependences - is a manifestation of individual characteristics of ferrihydrite nanoparticles. The induced anisotropy is caused by freezing of a subsystem of surface spins and its coupling with the particle core, which is observed in both samples at a temperature of ∼80 K. The temperature range (below 80 K) in which the gap exists corresponds to the blocked state in the FMR technique. In sample FH-bact, the ratio between the FMR parameters HA and linewidth ΔH obeys the standard expression HA ∼ (ΔH)3. In sample FH-chem, however, the interparticle magnetic interactions dramatically affect the behavior of parameters of the FMR spectra, which change nonmonotonically upon temperature variation. This fact is attributed to the collective freezing of the magnetic moments of particles under the conditions of sufficiently strong interactions, which follows from the temperature dependence of the particle magnetic moment relaxation time determined from the Mössbauer spectroscopy and static magnetometry data obtained in weak magnetic fields.

Смотреть статью,
Scopus,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Akademgorodok 50, bld. 38, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, Svobodniy 79, Krasnoyarsk, 660041, Russian Federation
Krasnoyarsk Scientific Center, Federal Research Center KSC SB RAS, Akademgorodok 50, Krasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Balaev, D. A.; Балаев, Дмитрий Александрович; Stolyar, S. V.; Столяр, Сергей Викторович; Knyazev, Yu. V.; Князев, Юрий Владимирович; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Pankrats, A. I.; Панкрац, Анатолий Иванович; Vorotynov, A. M.; Воротынов, Александр Михайлович; Krasikov, A. A.; Красиков, Александр Александрович; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Bayukov, O. A.; Баюков, Олег Артемьевич; Ladygina, V. P.; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
9.


   
    Ferrihydrite nanoparticles produced by Klebsiella oxytoca: Structure and properties dependence on the cultivation time / S. V. Stolyar, O. A. Bayukov, D. A. Balaev [et al.] // Adv. Powder Technol. - 2022. - Vol. 33, Is. 8. - Ст. 103692, DOI 10.1016/j.apt.2022.103692. - Cited References: 59. - This work was supported by Russian Foundation for Basic Research, Government of Krasnoyarsk Territory, Krasnoyarsk Region Science and Technology Support Fund to the research projects No. 20-416-242907 . - ISSN 0921-8831
Кл.слова (ненормированные):
Ferrihydrite nanoparticles -- Structure -- Microbial synthesis -- Mössbauer spectroscopy -- Small-angle X-ray scattering
Аннотация: Ferrihydrite nanoparticles were synthesized using Klebsiella oxytoca microorganisms under various cultivation conditions. The cultivation of bacteria was carried out under various lighting conditions, and the duration of cultivation varied from 3 to 56 days. Biogenic ferrihydrite nanoparticles were studied by Mössbauer spectroscopy, magnetometry, and small-angle X-ray scattering. The process of formation of ferrihydrite nanoparticles and the states arising during the cultivation of microorganisms have been investigated. The results of Mössbauer spectroscopy showed that, depending on the time of cultivation, three different states of ferrihydrite can be realized. States differ both in the ratio of defective and non-defective positions, and the size of the particle. Experimental results indicate that ferrihydrite nanoparticles are a system of variable composition and pass through several structural (or morphological) states during the cultivation of microorganisms. A model of the structure of ferrihydrite nanoparticles is proposed, which consists in the presence of an antiferromagnetic dense core with a high Néel temperature and a friable shell with a significantly lower temperature of magnetic ordering.

Смотреть статью,
Scopus
Держатели документа:
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk, Russian Federation
Krasnoyarsk Scientific Center, Federal Research Center KSC SB RAS Krasnoyarsk, Russian Federation
Siberian Federal University, Krasnoyarsk, Russian Federation
Joint Institute for Nuclear Research, Dubna, Russian Federation

Доп.точки доступа:
Stolyar, S. V.; Столяр, Сергей Викторович; Bayukov, O. A.; Баюков, Олег Артемьевич; Balaev, D. A.; Балаев, Дмитрий Александрович; Ladygina, V. P.; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Knyazev, Yu. V.; Князев, Юрий Владимирович; Balasoiu, M.; Kolenchukova, O. A.; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
10.


   
    Interparticle magnetic interactions in synthetic ferrihydrite: Mossbauer spectroscopy and magnetometry study of the dynamic and static manifestations / Y. V. Knyazev, D. A. Balaev, S. V. Stolyar [et al.] // J. Alloys Compd. - 2022. - Vol. 889. - Ст. 161623, DOI 10.1016/j.jallcom.2021.161623. - Cited References: 84. - This study was supported by the Russian Foundation for Basic Research, the Government of the Krasnoyarsk Territory, and the Krasnoyarsk Territorial Foundation for Support of Scientific and R&D Activities, project no. 19–42–240012 R-A “Magnetic Resonance in Ferrihydrite Nanoparticles: Effects Related to the Core-Shell Structure” . - ISSN 0925-8388
Кл.слова (ненормированные):
Ferrihydrite nanoparticles -- Superparamagnetism -- Interparticle magnetic interactions
Аннотация: Samples of synthetic ferrihydrite with an average nanoparticle size of 2.7 nm have been examined by magnetometry and Mossbauer spectroscopy. Ferrihydrite is characterized by the antiferromagnetic interactions between the magnetic moments of iron atoms. In ferrihydrite nanoparticles, as in any other antiferromagnetic ones, structural defects induce the formation of an uncompensated magnetic moment, which determines the magnetic properties typical of single-domain ferro- and ferrimagnetic particles. The manifestation of the magnetic interactions between ferrihydrite nanoparticles in the magnetic properties of the material and in the temperature evolution of Mossbauer spectra has been in focus. The results obtained on synthetic ferrihydrite have been compared with the data for the biogenic ferrihydrite sample with a similar average size of particles surrounded by a polysaccharide shell, which weakens and screens the interparticle magnetic interactions. A clear manifestation of the effect of the interparticle magnetic interactions on the transition to the blocked state is the presence of a significant contribution of the relaxation component in the Mossbauer spectra at temperatures of the transition from the superparamagnetic to blocked state. The temperature dependence of the particle relaxation time obtained from the Mossbauer spectra points out the collective effect of freezing of the magnetic moments of particles due to the magnetic interactions between them.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Akademgorodok 50, bld. 38, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, Svobodniy 79, Krasnoyarsk, 660041, Russian Federation
Krasnoyarsk Scientific Center, Federal Research Center KSC SB RAS, Akademgorodok 50, Krasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Knyazev, Yu. V.; Князев, Юрий Владимирович; Balaev, D. A.; Балаев, Дмитрий Александрович; Stolyar, S. V.; Столяр, Сергей Викторович; Krasikov, A. A.; Красиков, Александр Александрович; Bayukov, O. A.; Баюков, Олег Артемьевич; Volochaev, M. N.; Волочаев, Михаил Николаевич; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Ladygina, V. P.; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
11.


   
    Biogenic ferrihydrite nanoparticles produced by Klebsiella oxytoca: Characterization, physicochemical properties and bovine serum albumin interactions / N. Cazacu, C. G. Chilom, S. Iftimie [et al.] // Nanomaterials. - 2022. - Vol. 12, Is. 2. - Ст. 249, DOI 10.3390/nano12020249. - Cited References: 59. - This research was funded by JINR Themes 02-1-1107-2011/2021, 04-5-1131-2017/2021 and 04-4-1133-2018/2023 and with the financial support of the RO-JINR Projects Nos. 366/11.05.2021 (items 7, 86, 97) and 365/11.05.2021 (items 8, 87 and 98). This work also benefited from the use of the SasView application, originally developed under NSF Award DMR-0520547. SasView also contains the code developed with funding from the EU Horizon 2020 program under the SINE2020 project Grant No 654000. The APC was funded by JINR Theme 02-1-1107-2011/2021, Project No. 366/11.05.2021, item 7. This study used the infrastructure of the Applied Genetics Resource Facility of MIPT (Suport Grant 075-15-2021-684) . - ISSN 2079-4991
РУБ Chemistry, Multidisciplinary + Nanoscience & Nanotechnology + Materials Science, Multidisciplinary + Physics, Applied
Рубрики:
MAGNETIC-PROPERTIES
   REDUCTION

   MOSSBAUER

   FERRITIN

   DOCKING

   BINDING

Кл.слова (ненормированные):
biogenic ferrihydrite nanoparticles -- the binding mechanism -- energy transfer -- protein stability -- molecular docking
Аннотация: The synthesis of nanoparticles inside microorganisms is an economical alternative to chemical and physical methods of nanoparticle synthesis. In this study, ferrihydrite nanoparticles synthesized by Klebsiella oxytoca bacterium in special conditions were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDS), small-angle X-ray (SAXS), UV-Vis spectroscopy, fluorescence, fluorescence resonance energy transfer (FRET), and molecular docking. The morphology and the structure of the particles were characterized by means of SEM and SAXS. The elemental content was determined by means of the EDS method. The absorption properties of the ferrihydrite nanoparticles were investigated by UV-Vis spectroscopy. The binding mechanism of the biogenic ferrihydrite nanoparticles to Bovine Serum Albumin (BSA) protein, studied by fluorescence, showed a static and weak process, combined with FRET. Protein denaturation by temperature and urea in the presence of the ferrihydrite nanoparticles demonstrated their influence on the unfolding process. The AutoDock Vina and UCSF Chimera programs were used to predict the optimal binding site of the ferrihydrite to BSA and to find the location of the hydrophobic cavities in the sub-domain IIA of the BSA structure.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
Univ Bucharest, Fac Phys, Dept Elect Solid State & Biophys, RO-077125 Magurele, Romania.
Horia Hulubei Natl Inst Phys & Nucl Engn, Dept Nucl Phys, RO-077125 Magurele, Romania.
Joint Inst Nucl Res, Dubna 141980, Russia.
Moscow Inst Phys & Technol, Dolgoprudnyi 141701, Russia.
Russian Acad Sci, Siberian Branch, Fed Res Ctr KSC, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, Sch Engn Phys & Radio Elect, Phys Dept, Krasnoyarsk 660041, Russia.
Russian Acad Sci, Siberian Branch, Kirensky Inst Phys, Krasnoyarsk 660036, Russia.

Доп.точки доступа:
Cazacu, Nicoleta; Chilom, Claudia G.; Iftimie, Sorina; Balasoiu, Maria; Ladygina, Valentina P.; Stolyar, S. V.; Столяр, Сергей Викторович; Orelovich, Oleg L.; Kovalev, Yuriy S.; Rogachev, Andrey V.
}
Найти похожие
12.


   
    Heat release by ferrihydrite nanoparticles at ferromagnetic resonance / S. V. Stolyar, O. A. Li, V. P. Ladygina [et al.] // VIII Euro-Asian symposium "Trends in magnetism" (EASTMAG-2022) : Book of abstracts / program com. S. G. Ovchinnikov [et al.]. - 2022. - Vol. 2, Sect. M : Magnetism in biology and medicine. - Ст. M.P5. - P. 434 . - ISBN 978-5-94469-051-7

Материалы симпозиума,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk, Russia
Siberian Federal University, Krasnoyarsk, Russia
Krasnoyarsk Scientifi­c Center, FRC KSC SB RAS Krasnoyarsk, Russia

Доп.точки доступа:
Stolyar, S. V.; Столяр, Сергей Викторович; Li, O. A.; Ли, О. А.; Ladygina, V. P.; Ладыгина, Валентина Петровна; Nikolaeva, E. D.; Vorotynov, A. M.; Воротынов, Александр Михайлович; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Pyankov, V. F.; Iskhakov, R. S.; Исхаков, Рауф Садыкович; Российская академия наук; Физико-технический институт им. Е.К. Завойского ФИЦ Казанского научного центра РАН; Казанский (Приволжский) федеральный университет; Euro-Asian Symposium "Trends in MAGnetism"(8 ; 2022 ; Aug. ; 22-26 ; Kazan); "Trends in MAGnetism", Euro-Asian Symposium(8 ; 2022 ; Aug. ; 22-26 ; Kazan)
}
Найти похожие
13.


   
    Новый способ лечения ожоговых ран с помощью адресной доставки лекарственных веществ магнитным наноносителем (экспериментальная часть) / А. А. Богатиков, К. Г. Добрецов, М. В. Мелихова [и др.] // Журн. СФУ. Биология. - 2022. - Т. 15, № 3. - С. 422-436 ; J. Sib. Fed. Univ. Biol., DOI 10.17516/1997-1389-0396. - Библиогр.: 27. - Работа выполнена при финансовой поддержке Красноярского краевого фонда науки, Конкурс проектов организации участия студентов, аспирантов и молодых ученых в конференциях, научных мероприятиях и стажировках (II очередь 2021 года) (проект № 2021051707717) . - ISSN 1997-1389. - ISSN 2313-5530
   Перевод заглавия: A new method for treating burn wounds using targeted delivery of medicinal substances by magnetic nanocarrier (experimental part)
Кл.слова (ненормированные):
наночастицы -- ферригидрит -- левомеколь -- магнитное поле -- рана -- ожог -- раневая инфекция -- регенерация -- местное лечение -- nanoparticles -- ferrihydrite -- levomekol -- magnetic field -- wound -- burn -- wound infection -- regeneration -- topical therapy
Аннотация: Проведено экспериментальное исследование на лабораторных животных по изучению эффективности адресной доставки мази левомеколь с помощью магнитных наночастиц и внешнего магнитного поля при термических ожогах. В исследовании принимало участие 20 крыс с двумя очагами ожога. Крысы были разделены на 4 группы: без лечения, терапия с использованием мази левомеколь, лечение с использованием наночастиц, мази левомеколь и внешнего магнитного поля и только магнитотерапии. При гистологическом исследовании на 14-е сутки во всех группах в зоне термического повреждения кожи были отмечены признаки глубокого ожога III и IV степени с распространением некроза на всю глубину дермы и на мышцы. В группе с наночастицами, мазью левомеколь и магнитным полем на фоне уменьшения воспаления отмечалось очаговое появление грануляционной ткани. Таким образом, гистологические исследования ожогового раневого процесса лабораторных животных показали, что использование инновационного биологически активного ранозаживляющего средства на основе наночастиц в сочетании с мазью левомеколь улучшает регенерацию тканей и приводит к ускорению эпителизации, что в целом повышает результаты лечения ожоговой раны. Использование внешнего магнитного поля способствует адресной доставке лечебного нанокомплекса и поддержанию оптимальной концентрации препарата в ране.
Experimental studies have been carried out on laboratory animals to investigate the effectiveness of targeted delivery of levomekol ointment using magnetic nanoparticles and an external magnetic field for treatment of thermal burns. The study involved 20 rats, with two burns on each. The rats were divided into 4 groups: untreated; treated with levomekol ointment; treated with levomekol ointment associated with nanoparticles and an external magnetic field; and treated with magnetic field alone. Histological examination was conducted on Day 14, and in all groups, in the thermal burn zone of the skin there were signs of deep three- and four-degree burns with necrosis spread through the dermis, reaching the muscle. In the group with levomekol ointment associated with nanoparticles and magnetic field, inflammation was decreased, and focal granulation tissue formation was observed. Thus, histological studies of the burn wound process in laboratory animals showed that the use of an innovative biologically active wound healing agent based on nanoparticles in combination with the levomecol ointment improved tissue regeneration and accelerated epithelialization, which enhanced the effectiveness of burn wound treatment. The use of an external magnetic field facilitated targeted delivery of the therapeutic nanosystem and maintenance of the optimal concentration of the drug in the wound.

Смотреть статью,
РИНЦ
Держатели документа:
Северо-Западный окружной научно-клинический центр имени Л. Г. Соколова Федерального медико-биологического агентства, Российская Федерация, Санкт-Петербург
Институт токсикологии Федерального медико-биологического агентства, Российская Федерация, Санкт-Петербург
Федеральный исследовательский центр «Красноярский научный центр СО РАН», Российская Федерация, Красноярск
Красноярский государственный медицинский университет имени проф. В. Ф. Войно-Ясенецкого Министерства здравоохранения Российской Федерации, Российская Федерация, Красноярск
Санкт-Петербургский научно-исследовательский институт скорой помощи им. И. И. Джанелидзе, Российская Федерация, Санкт-Петербург
Российский государственный социальный университет, Российская Федерация, Москва

Доп.точки доступа:
Богатиков, А. А.; Добрецов, К. Г.; Мелихова, М. В.; Рожко, М. А.; Лапина, Н. В.; Столяр, Сергей Викторович; Stolyar, S. V.; Ярославцев, Роман Николаевич; Yaroslavtsev, R. N.; Баюков, Олег Артемьевич; Bayukov, O. A.; Тюменцева, А. В.; Николаева, Е. Д.; Тютрина, Е. С.; Зиновьев, Е. В.

}
Найти похожие
14.


   
    Superparamagnetic blocking and magnetic interactions in nanoferrihydrite adsorbed on biomineralized nanorod-shaped F3S4 crystallites / Y. V. Knyazev, O. P. Ikkert, S. V. Semenov [et al.] // J. Alloys Compd. - 2022. - Vol. 923. - Ст. 166346, DOI 10.1016/j.jallcom.2022.166346. - Cited References: 109. - This study was supported by the Russian Science Foundation, project no. 22-24-00601 (https://rscf.ru/project/22–24–00601/). - The electron microscopy and Mössbauer spectroscopy studies were carried out on the equipment of the Krasnoyarsk Territorial Center for Collective Use, Krasnoyarsk Scientific Center, Siberian Branch of the Russian Academy of Sciences. We thank Dr. Ivan Nemtsev for the SEM images. The contribution of M. P. (development of methodology of sample preparation for EXAFS measurements) was partially supported by the Russian Ministry of Science and Higher Education via the budget project of SRF SKIF, Boreskov Institute of Catalysis . - ISSN 0925-8388
Кл.слова (ненормированные):
Biomineralization -- Superparamagnetic nanoparticles -- Interparticle interactions -- Iron sulfide -- Ferrihydrite
Аннотация: A composite based on nanorod-shaped greigite (Fe3S4) crystallites with adsorbed ferrihydrite (Fe2O3 ‧ nH2O) nanoparticles has been synthesized. The synthesis has been performed by biomineralization of the bacterial wall of a sulfate-reducing Desulfovibrio sp. A2 bacteria. The phase composition of the synthesized composite has been investigated by X-ray powder and electron diffraction, as well as Fourier-transform infrared, extended X-ray absorption fine structure, and Mössbauer spectroscopy. The magnetic measurement data have shown that the sample under study contains two magnetic phases: multidomain nanorod-shaped greigite and ultrasmall ferrihydrite nanoparticles. The constant atomic fraction of the greigite crystalline phase in the range of 4–300 K (~20%) revealed by Mössbauer spectroscopy is indicative of a blocked magnetic moment of nanorod-shaped Fe3S4. It is shown that nanorod-shaped Fe3S4 crystallites are strongly magnetically bound with adsorbed Fe2O3 ‧ nH2O (Eint ~ 1200kB) nanoparticles. This significantly slows down the superparamagnetic relaxation of the magnetic moments of ferrihydrite nanoparticles. Therefore, the blocking temperature noticeably increases and attains, according to the Mössbauer spectroscopy data, a value of TB = 140 K (the magnetic measurements yield TB = 72 K). The processes of superparamagnetic blocking of the magnetic moments of ferrihydrite nanoparticles manifest themselves in the evolution of the magnetic properties of the investigated sample (a significant increase in the coercivity and remanent magnetization). In support of the Mössbauer spectroscopy data, a sufficiently high superparamagnetic blocking temperature has been established, which discloses the effect of magnetizing of ferrihydrite nanoparticles by coarser greigite formations, analogously to the effect of interparticle magnetic interactions.

Смотреть статью,
Scopus
Держатели документа:
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk, 660036, Russian Federation
Department of Plant Physiology, Biotechnology, and Bioinformatics, Tomsk State University, Tomsk, 634050, Russian Federation
Siberian Federal University, Krasnoyarsk, 660041, Russian Federation
Synchrotron radiation facility SKIF, Boreskov Institute of Catalysis SB RAS, Kol'tsovo, 630559, Russian Federation
National Research Center “Kurchatov Institute”, Moscow, 123182, Russian Federation

Доп.точки доступа:
Knyazev, Yu. V.; Князев, Юрий Владимирович; Ikkert, O. P.; Semenov, S. V.; Семёнов, Сергей Васильевич; Volochaev, M. N.; Волочаев, Михаил Николаевич; Molokeev, M. S.; Молокеев, Максим Сергеевич; Platunov, M. S.; Платунов, Михаил Сергеевич; Khramov, E. V.; Dubrovskiy, A. A.; Дубровский, Андрей Александрович; Shestakov, N. P.; Шестаков, Николай Петрович; Smorodina, E. D.; Karnachuk, O. V.; Balaev, D. A.; Балаев, Дмитрий Александрович
}
Найти похожие
15.


   
    Tuning of the interparticle interactions in ultrafine ferrihydrite nanoparticles / Y. V. Knyazev, D. A. Balaev, R. N. Yaroslavtsev [et al.] // Adv. Nano Res. - 2022. - Vol. 12, Is. 6. - P. 605-616, DOI 10.12989/anr.2022.12.6.605. - Cited References: 73. - This study was supported by the Russian Science Foundation, project no. 21-72-00025 “Tuning the Magnetic Properties of Ultrafine Biocompatible Ferrihydrite Nanoparticles through Interparticle Interactions” (https://rscf.ru/project/21-72-00025/) . - ISSN 2287-237X
Кл.слова (ненормированные):
ferrihydrite ultrafine nanoparticles -- hyperfine structure -- interparticle interactions -- iron oxyhydroxide -- superparamagnetic relaxation -- surface coatings
Аннотация: We prepared two samples of ultrafine ferrihydrite (FH) nanoparticle ensembles of quite a different origin. First is the biosynthesized sample (as a product of the vital activity of bacteria Klebsiella oxytoca (hereinafter marked as FH-bact) with a natural organic coating and negligible magnetic interparticle interactions. And the second one is the chemically synthesized ferrihydrite (hereinafter FH-chem) without any coating and high level of the interparticle interactions. The interparticle magnetic interactions have been tuned by modifying the nanoparticle surface in both samples. The coating of the FH-bact sample has been partially removed by annealing at 150℃ for 24 h (hereinafter FH-annealed). The FH-chem sample, vice versa, has been coated (1.0 g) with biocompatible polysaccharide (arabinogalactan) in an ultrasonic bath for 10 min (hereinafter FH-coated). The changes in the surface properties of nanoparticles have been controlled by XPS. According to the electron microscopy data, the modification of the nanoparticle surface does not drastically change the particle shape and size. A change in the average nanoparticle size in sample FH-annealed to 3.3 nm relative to the value in the other samples (2.6 nm) has only been observed. The estimated particle coating thickness is about 0.2-0.3 nm for samples FH-bact and FH-coated and 0.1 nm for sample FH-annealed. Mössbauer and magnetization measurements are definitely shown that the drastic change in the blocking temperature is caused by the interparticle interactions. The experimental temperature dependences of the hyperfine field hf>(T) for samples FH-bact and FH-coated have not revealed the effect of interparticle interactions. Otherwise, the interparticle interaction energy Eint estimated from the hf>(T) for samples FH-chem and FH-annealed has been found to be 121kB and 259kB, respectively.

Смотреть статью,
Scopus
Держатели документа:
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, Krasnoyarsk, 660041, Russian Federation
Institute of Chemistry and Chemical Technology, Federal Research Center KSC SB RAS, Krasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Knyazev, Yu. V.; Князев, Юрий Владимирович; Balaev, D. A.; Балаев, Дмитрий Александрович; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Krasikov, A. A.; Красиков, Александр Александрович; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Mikhlin, Y. L.; Volochaev, M. N.; Волочаев, Михаил Николаевич; Bayukov, O. A.; Баюков, Олег Артемьевич; Stolyar, S. V.; Столяр, Сергей Викторович; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
16.


   
    Magnetic hysteresis of blocked ferrihydrite nanoparticles / S. V. Komogortsev, D. A. Balaev, A. A. Krasikov [et al.] // AIP Adv. - 2021. - Vol. 11, Is. 1. - Ст. 015329, DOI 10.1063/9.0000111. - Cited References: 23. - The magnetic measurements were partially carried out on the equipment of the Krasnoyarsk Regional Center for Collective Use, Krasnoyarsk Science Center, Siberian Branch, Russian Academy of Sciences. This study was supported by the Council of the President of the Russian Federation for State Support of Young Scientists and Leading Scientific Schools (project no. MK-1263.2020.3) . - ISSN 2158-3226
Кл.слова (ненормированные):
Hysteresis -- Hysteresis loops -- Magnetic anisotropy -- Magnetic materials -- Nanoparticles -- Anisotropy field -- Ferrihydrites -- Field amplitudes -- Magnetic anisotropy field -- Minor hysteresis loop -- Stoner-Wohlfarth model -- Uniaxial anisotropy -- Nanomagnetics
Аннотация: Using minor hysteresis loops in the Stoner-Wohlfarth model allows describing the experimental behavior of the coercive force of minor hysteresis loops in ferrihydrite nanoparticles with a change in the field amplitude. The description allows estimating the parameters of the distribution of the magnetic anisotropy field in nanoparticles. The best agreement of the anisotropy fields estimated by different approaches is achieved for the assumption of uniaxial anisotropy in ferrihydrite nanoparticles.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics, Russian Academy of Sciences, Siberian Branch, Krasnoyarsk, 660036, Russian Federation
Krasnoyarsk Science Center, Russian Academy of Sciences, Siberian Branch, Krasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Komogortsev, S. V.; Комогорцев, Сергей Викторович; Balaev, D. A.; Балаев, Дмитрий Александрович; Krasikov, A. A.; Красиков, Александр Александрович; Stolyar, S. V.; Yaroslavtsev, R. N.; Ladygina, V. P.; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
17.


   
    Magnetic anisotropy and core-shell structure origin of the biogenic ferrihydrite nanoparticles / Y. V. Knyazev, D. A. Balaev, S. V. Stolyar [et al.] // J. Alloys Compd. - 2021. - Vol. 851. - Ст. 156753, DOI 10.1016/j.jallcom.2020.156753. - Cited References: 82. - The electron microscopy study was carried out on the equipment of the Krasnoyarsk Territorial Center for Collective Use, Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences. This study was supported by the Russian Foundation for Basic Research, the Government of the Krasnoyarsk Territory, and the Krasnoyarsk Territorial Foundation for Support of Scientific and R & D Activities, project no. 19-42-240012 p-a “Magnetic Resonance in Ferrihydrite Nanoparticles: Effects Related to the Core–Shell Structure” . - ISSN 0925-8388
Кл.слова (ненормированные):
Ferrihydrite -- Core-shell nanoparticles -- Superparamagnetism -- Surface magnetic anisotropy
Аннотация: Ferrihydrite is a low-crystalline nanoscale matter. The uncompensated magnetic moment of the ferrihydrite caused by the antiferromagnetic ordering of the magnetic moments of iron atoms and leads to the magnetic properties very similar to those of ferro- and ferrimagnetic nanoparticles. In this study, we investigated the biogenic ferrihydrite nanoparticles with the narrow size distribution and an average diameter of ≈2 nm obtained by the bacteria life cycle. The features caused by the surface effects and the inhomogeneous structure of ferrihydrite have been examined in the temperature range of 4–300 K using Mossbauer spectroscopy and magnetometry. Based on the Mossbauer data, we identified the superparamagnetic blocking temperature at the temperature of 30 K for the largest ferryhidrite particles. We established that the exceptional magnetic anisotropy of ferrihydrite (KV=1.2∙105 erg/cm3 and KS=0.1 erg/cm2) is reached because of the highly developed ferrihydrite nanoparticles’ surface. According to the Mossbauer data, we propose a core-shell structural model of the biogenic ferrihydrite particles. We found that the size of the dense core depends on the particle size. The well-crystallized core is formed only for nanoparticles larger than ≈2 nm, whereas smaller particles consist entirely of a matter with a lower density of iron atoms.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Akademgorodok 50, Bld. 38, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, Svobodniy 79, Krasnoyarsk, 660041, Russian Federation
Krasnoyarsk Scientific Center, Federal Research Center KSC SB RAS, Akademgorodok 50, Krasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Knyazev, Yu. V.; Князев, Юрий Владимирович; Balaev, D. A.; Балаев, Дмитрий Александрович; Stolyar, S. V.; Bayukov, O. A.; Баюков, Олег Артемьевич; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Ladygina, V. P.; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
18.


   
    Interactions of chemically synthesized ferrihydrite nanoparticles with human serum transferrin: Insights from fluorescence spectroscopic studies / C. G. Chilom, N. Sandu, S. Iftimie [et al.] // Int. J. Mol. Sci. - 2021. - Vol. 22, Is. 13. - Ст. 7034, DOI 10.3390/ijms22137034. - Cited References: 39. - The work was accomplished with the financial support of the RO-JINR Projects No. 365/11.05.2021, items 8, 87 and 98 and respectivelly, No. 366/11.05.2021, items 7, 86 and 97 . - ISSN 1661-6596
Кл.слова (ненормированные):
Ferrihydrite nanoparticles -- Human serum transferrin -- Binding mechanism -- Driving forces -- Molecular docking
Аннотация: Human serum transferrin (HST) is a glycoprotein involved in iron transport that may be a candidate for functionalized nanoparticles to bind and target cancer cells. In this study, the effects of the simple and doped with cobalt (Co) and copper (Cu) ferrihydrite nanoparticles (Fh-NPs, Cu-Fh-NPs, and Co-Fh-NPs) were studied by spectroscopic and molecular approaches. Fluorescence spectroscopy revealed a static quenching mechanism for all three types of Fh-NPs. All Fh-NPs interacted with HST with low affinity, and the binding was driven by hydrogen bonding and van der Waals forces for simple Fh-NPs and by hydrophobic interactions for Cu-Fh-NPs and Co-Fh-NPs binding, respectively. Of all samples, simple Fh-NPs bound the most to the HST binding site. Fluorescence resonance energy transfer (FRET) allowed the efficient determination of the energy transfer between HST and NPs and the distance at which the transfer takes place and confirmed the mechanism of quenching. The denaturation of the HST is an endothermic process, both in the case of apo HST and HST in the presence of the three types of Fh-NPs. Molecular docking studies revealed that Fh binds with a low affinity to HST (Ka = 9.17 × 103 M−1) in accord with the fluorescence results, where the interaction between simple Fh-NPs and HST was described by a binding constant of 9.54 × 103 M−1.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
Department of Electricity, Solid Physics and Biophysics, Faculty of Physics, University of Bucharest, Str Atomistilor 405, CP MG 11, Magurele, RO?077125, Romania
Joint Institute for Nuclear Research, Joliot?Curie No. 6, Dubna, 141980, Russian Federation
Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering, Magurele, RO?077125, Romania
Moscow Institute of Physics and Technology, Institutskiy Per. No. 9, Dolgoprudniy, 141701, Russian Federation
Krasnoyarsk Science Center of the Siberian, Branch of the Russian Academy of Sciences, Akademgorodok St. No.50, Krasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Chilom, C. G.; Sandu, N.; Iftimie, S.; Balasoiu, M.; Rogachev, A.; Orelovich, O.; Stolyar, S. V.; Столяр, Сергей Викторович
}
Найти похожие
19.


   
    Biogenic ferrihydrite nanoparticles: Synthesis, properties in vitro and in vivo testing and the concentration effect / S. V. Stolyar, O. A. Kolenchukova, A. V. Boldyreva [et al.] // Biomedicines. - 2021. - Vol. 9, Is. 3. - Ст. 323, DOI 10.3390/biomedicines9030323. - Cited References: 52. - This research was funded by the Russian Foundation for Basic Research, the Government of the Krasnoyarsk Territory and the Regional Science Foundation, grant number 20-416-242907 . - ISSN 2227-9059
РУБ Biochemistry & Molecular Biology + Medicine, Research & Experimental + Pharmacology & Pharmacy

Кл.слова (ненормированные):
ferrihydrite nanoparticles -- concentration effect -- microorganisms Klebsiella oxytoca -- neutrophilic granulocytes -- chemiluminescence -- toxicology
Аннотация: Biogenic ferrihydrite nanoparticles were synthesized as a result of the cultivation of Klebsiella oxytoca microorganisms. The distribution of nanoparticles in the body of laboratory animals and the physical properties of the nanoparticles were studied. The synthesized ferrihydrite nanoparticles are superparamagnetic at room temperature, and the characteristic blocking temperature is 23-25 K. The uncompensated moment of ferrihydrite particles was determined to be approximately 200 Bohr magnetons. In vitro testing of different concentrations of ferrihydrite nanoparticles for the functional activity of neutrophilic granulocytes by the chemiluminescence method showed an increase in the release of primary oxygen radicals by blood phagocytes when exposed to a minimum concentration and a decrease in secondary radicals when exposed to a maximum concentration. In vivo testing of ferrihydrite nanoparticles on Wister rats showed that a suspension of ferrihydrite nanoparticles has chronic toxicity, since it causes morphological changes in organs, mainly in the spleen, which are characterized by the accumulation of hemosiderin nanoparticles (stained blue according to Perls). Ferrihydrite can also directly or indirectly stimulate the proliferation and intracellular regeneration of hepatocytes. The partial detection of Perls-positive cells in the liver and kidneys can be explained by the rapid elimination from organs and the high dispersion of the nanomaterial. Thus, it is necessary to carry out studies of these processes at the systemic level, since the introduction of nanoparticles into the body is characterized by adaptive-proliferative processes, accompanied by the development of cell dystrophy and tension of the phagocytic system.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
RAS, Kirensky Inst Phys, Fed Res Ctr KSC SB, Krasnoyarsk 660036, Russia.
RAS, Krasnoyarsk Sci Ctr, Fed Res Ctr KSC SB, Krasnoyarsk 660036, Russia.
Siberian Fed Univ, Dept Biophys, Krasnoyarsk 660041, Russia.
RAS, Sci Res Inst Med Problems North, Fed Res Ctr KSC SB, Krasnoyarsk 660022, Russia.
RAS, Inst Biophys, Fed Res Ctr KSC SB, Krasnoyarsk 660036, Russia.

Доп.точки доступа:
Stolyar, S. V.; Столяр, Сергей Викторович; Kolenchukova, Oksana A.; Boldyreva, Anna V.; Kudryasheva, Nadezda S.; Gerasimova, Yu. V.; Герасимова, Юлия Валентиновна; Krasikov, A. A.; Красиков, Александр Александрович; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Bayukov, O. A.; Баюков, Олег Артемьевич; Ladygina, Valentina P.; Birukova, Elena A.; Russian Foundation for Basic ResearchRussian Foundation for Basic Research (RFBR); Government of the Krasnoyarsk Territory; Regional Science Foundation [20-416-242907]
}
Найти похожие
20.


   
    Features of relaxation of the remanent magnetization of antiferromagnetic nanoparticles by the example of ferrihydrite / D. A. Balaev, A. A. Krasikov, A. D. Balaev [et al.] // Phys. Solid State. - 2020. - Vol. 62, Is. 7. - P. 1172-1178, DOI 10.1134/S1063783420070033. - Cited References: 53 . - ISSN 1063-7834
Кл.слова (ненормированные):
antiferromagnetic nanoparticles -- ferrihydrite -- exchange bias -- magnetization relaxation
Аннотация: The relaxation of the remanent magnetization of antiferromagnetically ordered ferrihydrite nanoparticles at the exchange bias effect implemented in these systems has been investigated. The magnetization relaxation depends logarithmically on time, which is typical of the thermally activated hoppings of particle magnetic moments through the potential barriers caused by the magnetic anisotropy. The barrier energy obtained by processing of the remanent magnetization relaxation data under the field cooling conditions significantly exceeds the barrier energy under standard (zero field cooling) conditions. The observed difference points out the possibility of using the remanent magnetization relaxation to analyze the mechanisms responsible for the exchange bias effect in antiferromagnetic nanoparticles and measure the parameters of the exchange coupling of magnetic subsystems in such objects.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ

Публикация на русском языке Особенности релаксации остаточной намагниченности антиферромагнитных наночастиц на примере ферригидрита [Текст] / Д. А. Балаев, А. А. Красиков, А. Д. Балаев [и др.] // Физ. тверд. тела. - 2020. - Т. 62 Вып. 7. - С. 1043-1049

Держатели документа:
Kirensky Institute of Physics, Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, Krasnoyarsk, 660041, Russian Federation
Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, 660036, Russian Federation

Доп.точки доступа:
Balaev, D. A.; Балаев, Дмитрий Александрович; Krasikov, A. A.; Красиков, Александр Александрович; Balaev, A. D.; Балаев, Александр Дмитриевич; Stolyar, S. V.; Столяр, Сергей Викторович; Ladygina, V. P.; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие
 

Другие библиотеки

© Международная Ассоциация пользователей и разработчиков электронных библиотек и новых информационных технологий
(Ассоциация ЭБНИТ)