Библиотека института физики им. Л.В. Киренского СО РАН

Главная

Базы данных

Труды сотрудников ИФ СО РАН - результаты поиска

Вид поиска

Каталог книг и брошюр библиотеки ИФ СО РАН

Каталог журналов библиотеки ИФ СО РАН

Труды сотрудников ИФ СО РАН

Область поиска

в найденном

Формат представления найденных документов:
полный	информационный	краткий

Отсортировать найденные документы по:
автору	заглавию	году издания	типу документа

Поисковый запрос: (<.>K=Superparamagnetism<.>)

Общее количество найденных документов : 22
Показаны документы с 1 по 20

Magnetic properties of heat treated bacterial ferrihydrite nanoparticles / D. A. Balaev [et al.] // J. Magn. Magn. Mater. - 2016. - Vol. 410. - P. 171-180, DOI 10.1016/j.jmmm.2016.02.059. - Cited References: 66. - TEM studies were performed on facility of Resource Sharing Center of Krasnoyarsk Scientific Center of Siberian Branch of Russian Academy of Sciences. Authors acknowledge to M.N. Volochaev for the TEM measurements. . - ISSN 0304-8853

РУБ Materials Science, Multidisciplinary + Physics, Condensed Matter
Рубрики:
Hematite nanoparticles
   NiO nanoparticles
   Porous-glass
   Ferritin
   Particles
   Temperature
   Hysteresis
   Transition
   Anomalies
   Mossbauer
Кл.слова (ненормированные):
Ferrihydrite -- Nanoparticles -- Superparamagnetism
Аннотация: The magnetic properties of ferrihydrite nanoparticles, which are products of vital functions of Klebsiella oxitoca bacteria, have been studied. The initial powder containing the nanoparticles in an organic shell was subjected to low-temperature (T=160 °C) heat treatment for up to 240 h. The bacterial ferrihydrite particles exhibit a superparamagnetic behavior. Their characteristic blocking temperature increases from 26 to 80 K with the heat treatment. Analysis of the magnetization curves with regard to the magnetic moment distribution function and antiferromagnetic contribution shows that the low-temperature heat treatment enhances the average magnetic moment of a particle; i.e., the nanoparticles coarsen, probably due to their partial agglomeration during heat treatment. It was established that the blocking temperature nonlinearly depends on the particle volume. Therefore, a model was proposed that takes into account both the bulk and surface magnetic anisotropy. Using this model, the bulk and surface magnetic anisotropy constants KV≈1.7×105 erg/cm3 and KS≈0.055 erg/cm2 have been determined. The effect of the surface magnetic anisotropy of ferrihydrite nanoparticles on the observed magnetic hysteresis loops is discussed.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics, Russian Academy of Sciences, Siberian Branch, Krasnoyarsk, Russian Federation
Siberian Federal University, Krasnoyarsk, Russian Federation
Presidium of Krasnoyarsk Scientific Center, Russian Academy of Sciences, Siberian Branch, Krasnoyarsk, Russian Federation
International Laboratory of High Magnetic Fields and Low Temperatures, Gajowicka 95, Wroclaw, Poland

Доп.точки доступа:
Balaev, D. A.; Балаев, Дмитрий Александрович; Krasikov, A. A.; Красиков, Александр Александрович; Dubrovskiy, A. A.; Дубровский, Андрей Александрович; Popkov, S. I.; Попков, Сергей Иванович; Stolyar, S. V.; Столяр, Сергей Викторович; Bayukov, O. A.; Баюков, Олег Артемьевич; Iskhakov, R. S.; Исхаков, Рауф Садыкович; Ladygina, V. P.; Yaroslavtsev, R. N.
}
Найти похожие

Formation and evolution of magnetic nanoparticles in borate glass simultaneously doped with Fe and Mn oxides / J. . Kliava [et al.] // J. Appl. Phys. - 2008. - Vol. 104, Is. 10. - Ст. 103917, DOI 10.1063/1.3021289. - Cited References: 37. - A financial support from the Russian Foundation for Basic Research (RFBR)-CNRS (Grant No. 07-02-92174) is highly appreciated. R. Ivantsov is grateful to the Russian Science Support Foundation. Y. Yeshurun acknowledges the support of the Israel Scienc Foundation (ISF). . - ISSN 0021-8979

РУБ Physics, Applied
Рубрики:
COBALT FERRITE PARTICLES
   SUPERPARAMAGNETIC RESONANCE
   GAMMA-FE2O3 NANOPARTICLES
   MATRIX
   SIZE
   SYSTEMS
Кл.слова (ненормированные):
aluminium compounds -- borate glasses -- coercive force -- Faraday effect -- heat treatment -- iron compounds -- magnetic hysteresis -- magnetic particles -- magnetic susceptibility -- manganese compounds -- Mossbauer effect -- nanoparticles -- paramagnetic materials -- potassium compounds -- remanence -- superparamagnetism -- transmission electron microscopy -- X-ray chemical analysis -- Atomic spectroscopy -- Auger electron spectroscopy -- Crystal structure -- Electric relays -- Electronic medical equipment -- Ferrite -- Ferrites -- Glass -- Heat treatment -- Hysteresis -- Hysteresis loops -- Magnetic properties -- Magnetic resonance measurement -- Magnetic susceptibility -- Magnetism -- Manganese -- Manganese compounds -- Molybdenum -- Nanoparticles -- Optical properties -- Ozone water treatment -- Polydispersity -- Superparamagnetism -- Borate glasses -- Concentration ratios -- Electron magnetic resonances -- Emr spectrums -- Experimental techniques -- Faraday rotations -- Glass compositions -- Glass matrixes -- Glass preparations -- Magnetic measurements -- Magnetic nano particles -- Magnetic orders -- Magnetically ordered systems -- Magneto-optical properties -- Manganese ferrites -- Mean diameters -- Mn oxides -- Phase states -- Polydisperse nanoparticles -- Remnant magnetizations -- Ssbauer spectroscopies -- Superparamagnetic -- Superparamagnetic states -- Thermal treatments -- Variable temperatures -- Magnetic materials
Аннотация: Evolution of the phase state of paramagnetic additions at various stages of synthesis and subsequent thermal treatment of glasses of the system Al(2)O(3)-K(2)O-B(2)O(3) simultaneously doped with Fe(2)O(3) and MnO is studied by means of a combination of experimental techniques: Faraday rotation (FR), electron magnetic resonance (EMR), transmission electron microscopy (TEM), Mossbauer spectroscopy, and magnetic measurements. Both FR and EMR show that magnetically ordered clusters occur already at the first stage of the glass preparation. In particular, for the ratio of the Fe and Mn oxides in the charge close to 3:2, fine magnetic nanoparticles are formed with characteristics similar to those of manganese ferrite. By computer simulating the EMR spectra at variable temperatures, a superparamagnetic nature of these nanoparticles is confirmed and their mean diameter is estimated as approximately 3.2 nm. In the thermally treated glasses larger magnetic nanoparticles are formed, giving rise to FR spectra, characteristic of magnetically ordered systems, and the EMR spectra different from those in as-prepared glasses but also showing superparamagnetic narrowing. The Mossbauer spectroscopy corroborates the manganese ferrite structure of the nanoparticles and indicates their coexistence in the ferrimagnetic and superparamagnetic states. The TEM shows the presence of polydisperse nanoparticles on the background of the glass matrix, and electron diffraction of a selected region containing larger particles indicates a crystal structure close to that of MnFe(2)O(4). Energy-dispersive atomic x-ray spectra confirm that the major part of Fe and Mn introduced to the glass composition is gathered in the particles, with the concentration ratio close to 2:1, characteristic of bulk MnFe(2)O(4). Magnetic hysteresis loops of samples subjected to an additional thermal treatment demonstrate a strong increase in the coercive force, remnant magnetization, and high-field magnetic susceptibility with temperature decrease. The consistent results obtained using various techniques demonstrate that the formation of nanoparticles with characteristics close to those of MnFe(2)O(4) confers to these glasses magnetic and magneto-optical properties typical of substances possessing magnetic order.

WOS,
Scopus,
Читать в сети ИФ
Держатели документа:
[Kliava, J.] Univ Bordeaux 1, CNRS, UMR 5798, CPMOH, F-33405 Talence, France
[Edelman, I.
Ivanova, O.
Ivantsov, R.
Bayukov, O.
Petrakovskaja, E.
Stepanov, S.] RAS, Siberian Branch, LV Kirensky Phys Inst, Krasnoyarsk 660036, Russia
[Zaikovskiy, V.] RAS, Siberian Branch, Boreskov Inst Catalysis, Novosibirsk 630090, Russia
[Bruckental, I.
Yeshurun, Y.] Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel
[Stepanov, S.] SI Vavilov State Opt Inst, St Petersburg 199034, Russia
ИФ СО РАН
CPMOH, Universit? Bordeaux, 1-CNRS UMR 5798, 33405 Talence Cedex, France
Kirensky Institute of Physics, Siberian Branch of RAS, 660036 Krasnoyarsk, Russian Federation
Boreskov Institute of Catalysis, Siberian Branch, RAS, 630090 Novosibirsk, Russian Federation
Department of Physics, Bar-Ilan University, Ramat-Gan 52900, Israel
S. I. Vavilov State Optical Institute, St. Petersburg 199034, Russian Federation

Доп.точки доступа:
Kliava, J.; Edelman, I. S.; Эдельман, Ирина Самсоновна; Ivanova, O. S.; Иванова, Оксана Станиславовна; Ivantsov, R. D.; Иванцов, Руслан Дмитриевич; Bayukov, O. A.; Баюков, Олег Артемьевич; Petrakovskaja, E. A.; Петраковская, Элеонора Анатольевна; Zaikovskiy, V.; Bruckental, I.; Yeshurun, Y.; Stepanov, S.
}
Найти похожие

Unusual magnetic phase transitions in Gd3+ clusters in multicomponent oxide glasses / J. . Kliava [et al.] // J. Supercond. Nov. Magn. - 2007. - Vol. 20, Is. 2. - P. 149-153, DOI 10.1007/s10948-006-0116-4. - Cited References: 7 . - ISSN 1557-1939

РУБ Physics, Applied + Physics, Condensed Matter
Рубрики:
GADOLINIUM
RESONANCE
Кл.слова (ненормированные):
oxide glasses -- gadolinium -- magnetic clusters -- superparamagnetism -- Gadolinium -- Magnetic clusters -- Oxide glasses -- Superparamagnetism -- Magnetic clusters -- Magnetic phase transitions -- Oxide glasses -- Weiss constant -- Antiferromagnetic materials -- Ferromagnetic materials -- Gadolinium -- Magnetic anisotropy -- Magnetic susceptibility -- Paramagnetic resonance -- Phase transitions -- Positive ions -- Superparamagnetism -- Glass
Аннотация: Magnetic susceptibility, EPR and optical properties have been studied in a glass system {20La(2)O(3) - 22Al(2)O(3) - 23B(2)O(3) - 35(SiO2 + GeO2)} with a part of La2O3 substituted by Gd2O3 in different concentrations. Positive Weiss constants have been found in more heavily doped glasses; two magnetic transitions at 55 and 12 K have been detected and ascribed, respectively, to ferromagnetic and antiferromagnetic clusters of Gd3+ ions. The EPR spectra confirm the clustering at higher Gd contents. At low temperatures the cluster-related resonance indicates an onset of magnetic anisotropy. The clustering, depending on the Gd concentration, correlates with a shift to lower energies of the strong optical absorption band edge.

WOS,
Scopus,
Читать в сети ИФ
Держатели документа:
Univ Bordeaux 1, Cours Liberat 351, CP MOH, UMR 5798, F-33405 Talence, France
RAS, SB, LV Kirensky Inst Phys, Krasnoyarsk 660036, Russia
Bar Ilan Univ, Dept Phys, IL-52900 Ramat Gan, Israel
SV Vavilov State Opt Inst, St Petersburg 199034, Russia
ИФ СО РАН
CPMOH, UMR 5798 CNRS-Universite Bordeaux-I, 33405 Talence Cedex, France
L.V. Kirensky Institute of Physics, SB, RAS, Krasnoyarsk 660036, Russian Federation
Bar-Ilan University, Department of Physics, Ramat-Gan 52900, Israel
S.V. Vavilov State Optical Institute, St.-Petersburg 199034, Russian Federation
CPMOH, Universite Bordeaux-I, 351 Cours de la Liberation, 33405 Talence Cedex, France

Доп.точки доступа:
Kliava, J.; Malakhovskii, A. V.; Малаховский, Александр Валентинович; Edelman, I. S.; Эдельман, Ирина Самсоновна; Potseluyko, A. M.; Petrakovskaja, E. A.; Петраковская, Элеонора Анатольевна; Bruckental, I.; Yeshurun, Y.; Zarubina, T.
}
Найти похожие

Superparamagnetism of magnetite particles in C-60 fullerite powder / E. A. Petrakovskaya [et al.] // Tech. Phys. - 2005. - Vol. 50, Is. 6. - P. 790-793, DOI 10.1134/1.1947359. - Cited References: 9 . - ISSN 1063-7842

РУБ Physics, Applied
Рубрики:
RESONANCE
Аннотация: A new magnetic material, C-60 fullerite powder doped by magnetite (Fe3O4) nanoparticles, is obtained by heating a mixture of fullerite and iron(III) acetylacetonate. It is shown that the material offers superparamagnetic properties. Surface bonding between the nanoparticles and the fullerite is established. (c) 2005 Pleiades Publishing, Inc.

WOS,
Scopus,
Читать в сети ИФ
Держатели документа:
Russian Acad Sci, Siberian Div, Kirenskii Inst Phys, Krasnoyarsk 660036, Russia
ИФ СО РАН
Kirenskii Institute of Physics, Siberian Division, Russian Academy of Sciences, Krasnoyarsk, Akademgorodok, 660036, Russian Federation

Доп.точки доступа:
Petrakovskaya, E. A.; Петраковская, Элеонора Анатольевна; Isakova, V. G.; Исакова, Виктория Гавриловна; Bayukov, O. A.; Баюков, Олег Артемьевич; Velikanov, D. A.; Великанов, Дмитрий Анатольевич
}
Найти похожие

Superparamagnetic and ferrimagnetic nanoparticles in glass matrix / I. S. Edelman [et al.] // Physica B. - 2001. - Vol. 301, Is. 3-4. - P. 203-211, DOI 10.1016/S0921-4526(01)00274-5. - Cited References: 9 . - ISSN 0921-4526

РУБ Physics, Condensed Matter
Рубрики:
MAGNETIC-PROPERTIES
PARTICLES
FILMS
Кл.слова (ненормированные):
magnetic nanoparticles -- Faraday rotation -- Faraday rotation -- Magnetic nanoparticles -- Crystal structure -- Faraday effect -- Ferrimagnetic materials -- Glass -- Particle size analysis -- Superparamagnetism -- X ray diffraction analysis -- Amorphous glass matrices -- Faraday rotations -- Nanostructured materials
Аннотация: Faraday rotation (FR) spectral, field, and temperature dependencies in oxide glasses with small additions of paramagnetic elements are investigated. Formation of ferrite nanoparticles in amorphous glass matrices is revealed by X-ray diffraction. Particles have crystal structure similar to spinel structure, their dimensions are about 10-24 nm. The FR field dependencies are typical for ferrimagnetic or superparamagnetic substances depending on particle size. Strong FR increase at the samples cooling (more than twice for some samples) in the temperature interval 105-273 K is observed. (C) 2001 Elsevier Science B.V. All rights reserved.

WOS,
Scopus,
Читать в сети ИФ
Держатели документа:
Russian Acad Sci, LV Kirensky Phys Inst, Krasnoyarsk 660036, Russia
SI Vavilov State Opt Inst, St Petersburg 193117, Russia
ИФ СО РАН
L.V. Kirensky Institute of Physics, Russian Academy of Sciences-SB, Krasnoyarsk 660036, Russian Federation
S.I. Vavilov Optical State Institute, St. Peterburg 193117, Russian Federation

Доп.точки доступа:
Edelman, I. S.; Эдельман, Ирина Самсоновна; Ivantsov, R.; Vasiliev, A.; Stepanov, S.; Kornilova, E.; Zarubina, T.
}
Найти похожие

Magnetic resonance in FexMn1-xS single crystals / A. M. Vorotynov [et al.] // J. Appl. Phys. - 2009. - Vol. 106, Is. 7. - Ст. 73909, DOI 10.1063/1.3234402. - Cited References: 11. - This study was supported by the SB RAS-INTAS (Grant No. 06-1000013-9002) and the JSPS KAKENHI (Grant No. 18540317). . - ISSN 0021-8979

РУБ Physics, Applied

Кл.слова (ненормированные):
Experimental studies -- Ferromagnetic particles -- First-order -- Iron nanoparticles -- Manganese sulfide -- Mean diameter -- Randomly distributed -- Resonance spectrum -- S-matrix -- Superparamagnetics -- Computer simulation -- Manganese -- Manganese compounds -- Resonance -- Superparamagnetism -- Single crystals
Аннотация: The results of the experimental study and computer simulation of the resonance spectra of a single crystal of the iron-manganese sulfide FexMn1-xS (0 <=x <=0.29) are presented. The resonance properties of the concentrated solid solutions are explained by the formation of a homogeneous FexMn1-xS matrix with randomly distributed superparamagnetic iron nanoparticles. The mean diameter (< D > = 6.19 nm at T=250 K) and the axial first-order anisotropy constant (K-1 = 4.08 erg/cm(3) at T=250 K) of the ferromagnetic particles are determined. The volume fraction of the iron phase is estimated. (C) 2009 American Institute of Physics. [doi:10.1063/1.3234402]

WOS,
Scopus,
Читать в сети ИФ
Держатели документа:
Bovina, A. F.] Russian Acad Sci, LV Kirensky Phys Inst, Siberian Branch, Krasnoyarsk 660036, Russia
[Sokolov, V. V.] Russian Acad Sci, Nikolaev Inst Inorgan Chem, Siberian Branch, Novosibirsk 630090, Russia
[Mita, E.] Osaka Univ, Toyonaka, Osaka 5608531, Japan
Kirensky Institute of Physics, Russian Academy of Sciences, Siberian Branch, Krasnoyarsk, 660036, Russian Federation
Nikolaev Institute of Inorganic Chemistry, Russian Academy of Sciences, Siberian Branch, Novosibirsk, 630090, Russian Federation
Osaka University, Toyonaka 560-8531, Japan

Доп.точки доступа:
Vorotynov, A. M.; Воротынов, Александр Михайлович; Abramova, G. M.; Абрамова, Галина Михайловна; Popov, M. A.; Petrakovskii, G. A.; Петраковский, Герман Антонович; Bovina, A. F.; Бовина, Ася Федоровна; Sokolov, V. V.; Mita, E.; SB RAS-INTAS [06-1000013-9002]; JSPS KAKENHI [18540317]
}
Найти похожие

Khrustalev, B. P.
Superparamagnetism in Fe-SiO nanocluster films / B. P. Khrustalev, A. D. Balaev, V. M. Sosnin // Fiz. Tverd. Tela. - 1995. - Vol. 37, Is. 6. - P. 1676-1686. - Cited References: 30 . - ISSN 0367-3294

РУБ Physics, Condensed Matter
Рубрики:
ELECTRICAL-PROPERTIES
TEMPERATURE

WOS

Доп.точки доступа:
Balaev, A. D.; Балаев, Александр Дмитриевич; Sosnin, V. M.; Соснин, Виктор Михайлович; Хрусталев, Борис Петрович
}
Найти похожие

The unusual size dependence of magnetic properties of nickel zinc ferrite nanoparticles synthesized by combustion method / O. A. Li [et al.] // VI Euro-Asian Symposium "Trends in MAGnetism" (EASTMAG-2016) : abstracts / ed.: O. A. Maksimova, R. D. Ivantsov. - Krasnoyarsk : KIP RAS SB, 2016. - Ст. P9.5. - P. 391 . - ISBN 978-5-904603-06-9
Кл.слова (ненормированные):
nickel zinc ferrite -- ferrite nanoparticles -- superparamagnetism

Доп.точки доступа:
Li, O. A.; Ли О.А.; Edelman, I. S.; Эдельман, Ирина Самсоновна; Chun-Rong Lin; Hung-Yi Chen; Kai-Wun Wu; Ovchinnikov, S. G.; Овчинников, Сергей Геннадьевич; Euro-Asian Symposium "Trends in MAGnetism"(6 ; 2016 ; Aug. ; 15-19 ; Krasnoyarsk); "Trends in MAGnetism", Euro-Asian Symposium(6 ; 2016 ; Aug. ; 15-19 ; Krasnoyarsk); Институт физики им. Л.В. Киренского Сибирского отделения РАН

Нет сведений об экземплярах }
Найти похожие

Anisometric iron oxide-based nanoparticles and sols based on them: Preparation and properties / S. V. Stolyar [et al.] // J. Supercond. Novel Magn. - 2019. - Vol. 32, Is. 4. - P. 971–975, DOI 10.1007/s10948-018-4784-7. - Cited References: 18. - The reported study was carried out with the financial support of the Russian Foundation for Fundamental Research, the Government of the Krasnoyarsk Territory, and the Krasnoyarsk Territory Fund for Support of Scientific and Technical Activity in the framework of scientific Projects No. 18-43-243003, No. 17-42-240080 and No. 17-43-240527. The work is supported by the Special Program of the Ministry of Education and Science of the Russian Federation for the Siberian Federal University. . - ISSN 1557-1939
Кл.слова (ненормированные):
Nanoparticles and nanorods -- Chemical preparation -- Superparamagnetism
Аннотация: We have synthesized magnetic powders of the magnetite-maghemite series by the chemical reaction of the FeSO4 iron salt and the natural arabinogalactan polysaccharide. These particles with a high magnetization value (∼ 300 Gs) represent a mixture of spherical particles and nanorods. Particles of a spherical shape (diameter of ∼ 5–6 nm) show a superparamagnetic behavior at room temperature, while rods with a diameter of ∼ 5 nm and a length of 30 nm are magnetic. We have prepared sol samples based on the nanoparticle aqueous solution of arabinogalactan. Our results on the magnetism of the circular dichroism (MCD) on sol are consistent with the of Mössbauer spectroscopy data.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
Siberian Federal University, Krasnoyarsk, Russian Federation
Krasnoyarsk Scientific Center, Federal Research Center KSC SB RAS, Krasnoyarsk, Russian Federation
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk, Russian Federation

Доп.точки доступа:
Stolyar, S. V.; Bayukov, O. A.; Баюков, Олег Артемьевич; Chekanova, L. A.; Чеканова, Лидия Александровна; Gerasimova, Y. V.; Герасимова, Юлия Валентиновна; Sokolov, A. Е.; Соколов, Алексей Эдуардович; Iskhakov, R. S.; Исхаков, Рауф Садыкович; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Volochaev, M. N.; Волочаев, Михаил Николаевич; Artemyeva, A. S.; Cheremiskina, E. V.; Knyazev, Yu. V.; Князев, Юрий Владимирович
}
Найти похожие

10.

    Mossbauer spectroscopy study of the superparamagnetism of ultrasmall ε-Fe2O3 nanoparticles / Y. V. Knyazev [et al.] // JETP Letters. - 2018. - Vol. 108, Is. 8. - P. 527-531, DOI 10.1134/S0021364018200092. - Cited References: 22. - This work was supported by the Russian Science Foundation (project no. 17-12-01111). . - ISSN 0021-3640. - ISSN 1090-6487
Рубрики:
High-temperature
   Particles
   ε-Fe2O3
   Phase
   Model
Аннотация: The superparamagnetism of an ensemble of ϵ-Fe2O3 nanoparticles with a mean size of 3.9 nm dispersed in a xerogel SiO2 matrix is studied by the Mössbauer spectroscopy method. It is shown that most nanoparticles at room temperature are in the superparamagnetic (unblocked) state. As the temperature decreases, the progressive blocking of the magnetic moments of the particles occurs, which is manifested in the Mössbauer spectra as the transformation of the quadrupole doublet into a Zeeman sextet. The analysis of the relative intensity of the superparamagnetic (quadrupole doublet) and magnetically split (sextets) spectral components in the range of 4–300 K provides the particle size distribution, which is in agreement with the transmission electron microscopy data. The values of the effective magnetic anisotropy constants (Keff) are determined, and the contribution of surface anisotropy (KS) is estimated for particles of various sizes. It is shown that the quantity Keff is inversely proportional to the particle size, which indicates the significant contribution of the surface to the magnetic state of the ϵ-Fe2O3 nanoparticles with the size of several nanometers.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ

Публикация на русском языке Изучение суперпарамагнетизма ультрамалых наночастиц ε-Fe2O3 методом мессбауэровской спектроскопии [Текст] / Ю. В. Князев [и др.] // Письма в ЖЭТФ. - 2018. - Т. 108 № 7-8. - С. 558-562

Держатели документа:
Russian Acad Sci, Kirensky Inst Phys, Fed Res Ctr KSC, Siberian Branch, Krasnoyarsk 660036, Russia.
Russian Acad Sci, Boreskov Inst Catalysis, Siberian Branch, Novosibirsk 630090, Russia.

Доп.точки доступа:
Knyazev, Yu. V.; Князев, Юрий Владимирович; Balaev, D. A.; Балаев, Дмитрий Александрович; Kirillov, V. L.; Bayukov, O. A.; Баюков, Олег Артемьевич; Mart'yanov, O. N.; Russian Science Foundation [17-12-01111]
}
Найти похожие

11.

    Yurkin, G. Yu.
    Magnetic Properties of Fe1-xCoxSi Single Crystals at Low Co Impurity Concentrations / G. Y. Yurkin, G. S. Patrin, S. A. Yarikov // J. Sib. Fed. Univ. Math. Phys. - 2019. - Vol. 12, Is. 1. - P. 94-99 ; Журнал СФУ. Математика и физика, DOI 10.17516/1997-1397-2019-12-1-94-99. - Cited References: 17 . - ISSN 1997-1397. - ISSN 2313-6022
   Перевод заглавия: Магнитные свойства монокристаллов Fe1-x CoxSi при малой концентрации примеси Co
Кл.слова (ненормированные):
Co impurities -- iron silicide -- superparamagnetism -- силицид железа -- примесь Co -- суперпарамагнетизм
Аннотация: Magnetostatic properties of FeSi and Fe0,98Co0,02Si single crystals have been studied. It has been found that the temperature and field dependences of the magnetization of monocrystal FeSi are strongly affected by introduction of a small amount of Co (2 %). A description of the results were provided by a model accounting for the formation of superparamagnetic iron clusters, as well as Fe-Co complexes. It is assumed that Fe-Co complexes form a ferromagnetic phase, which is approximately 0.6% of the Fe0,98Co0,02Si sample weight.
В работе представлено исследование магнитостатических характеристик образцов FeSi и Fe0,98Co0,02Si. Обнаружено, что внесение небольшого количества примести Co(2%) значительно влияет на температурные и полевые зависимости намагниченности монокристалла FeSi. Результаты обработаны в рамках модели, учитывающей образование суперпарамагнитных кластеров железа, а также комплексов Fe-Co. Предполагается, что комплексы Fe-Co образуют ферромагнитную фазу, которая составляет примерно 0,6 % от массы образца Fe0,98Co0,02Si.

Смотреть статью,
РИНЦ,
Scopus, ,
Читать в сети ИФ
Держатели документа:
Siberian Fed Univ, Inst Engn Phys & Radio Elect, Svobodny 79, Krasnoyarsk 660041, Russia.
Kirensky Inst Phys SB RAS, Akademgorodok 50-38, Krasnoyarsk 660036, Russia.

Доп.точки доступа:
Patrin, G. S.; Патрин, Геннадий Семёнович; Yarikov, Stanislav A.; Яриков, Станислав Алексеевич; Юркин, Глеб Юрьевич

}
Найти похожие

12.

    Magnetic and magneto-optical properties of Fe3O4 nanoparticles modified with Ag / D. A. Petrov [et al.] // J. Magn. Magn. Mater. - 2020. - Vol. 493. - Ст. 165692, DOI 10.1016/j.jmmm.2019.165692. - Cited References: 45. - The reported study was funded by Russian Foundation for Basic Research, Government of Krasnoyarsk Territory, Krasnoyarsk Regional Fund of Science to the research project № 18-42-243021 and by Joint Research Project of Russian Foundation for Basic Research № 19-52-52002 and Ministry of Science and Technology, Taiwan MOST № 108-2923-M-153-001-MY3 and № 106-2112-M-153-001-MY3. . - ISSN 0304-8853
   Перевод заглавия: Магнитные и магнитооптические свойства наночастиц Fe3O4, модифицированных серебром
Кл.слова (ненормированные):
Fe3O4–Ag nanostructures -- Superparamagnetism -- Magnetic circular dichroism
Аннотация: Effect of Ag inclusions on magnetic properties and magnetic circular dichroism (MCD) of Fe3O4 nanoparticles (NPs) in the mixed system of Fe3O4 and Ag NPs in dependence on the relative concentration of the components is presented. The samples were synthesized by the thermal decomposition of the mixture of constant concentration of Fe(NO3)3·9H2O and varied concentration of AgNO3. The synthesized powdered samples consisted of Fe3O4 and Ag NPs located very close with each other, and in the most cases the Fe3O4 NPs were bordered with the Ag nanocrystals. The Ag introducing in the samples does not effect, practically, in the Fe3O4 NPs morphology and size distribution. At the same time, Ag NPs in the powdered samples cause a decrease in the Fe3O4 NPs magnetization and shift of the blocking temperature to lower temperatures, both approximately proportional to the Ag concentration. Most significant changes are revealed in the MCD spectra in the energy region of 1.2–2.2 eV. We have discussed the influence of the Ag NPs on the MCD spectra features in terms of the charge-transfer electron transitions. © 2019 Elsevier B.V.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics SB RAS, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, Svobodny Av., 79, Krasnoyarsk, 660041, Russian Federation
National Pingtung University, Pingtung City, Pingtung County 90003, Taiwan

Доп.точки доступа:
Petrov, D. A.; Петров, Дмитрий Анатольевич; Ivantsov, R. D.; Иванцов, Руслан Дмитриевич; Zharkov, S. M.; Жарков, Сергей Михайлович; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Molokeev, M. S.; Молокеев, Максим Сергеевич; Lin, C. -R.; Tso, C. -T.; Hsu, H. -S.; Tseng, Y. -T.; Lin, E. -S.; Edelman, I. S.; Эдельман, Ирина Самсоновна
}
Найти похожие

13.

    Yurkin, G. Yu.
    Magnetic Properties of Fe1-xCoxSi Single Crystals at Low Co Impurity Concentrations / G. Yu. Yurkin, G. S. Patrin, S. A. Yarikov // J. Sib. Fed. Univ. Math. Phys. - 2019. - Vol. 12, Is. 6. - P. 756-771 ; Журн. СФУ. Матем. и физика, DOI 10.17516/1997-1397-2019-12-1-1-6. - Cited References: 17 . - ISSN 1997-1397. - ISSN 2313-6022
   Перевод заглавия: Магнитные свойства монокристаллов Fe1-xCoxSi
Кл.слова (ненормированные):
Co impurities -- iron Silicide -- superparamagnetism -- силицид железа -- примесь Co -- суперпарамагнетизм
Аннотация: Velocity of bulk acoustic waves in base and rotated cuts have been measured by the ultrasonic pulse-echo method and values of CE ijkl and eijk in single crystals YAl3(BO3)4 have been calculated. The value of dijk piezoelectric modulus of these single crystals have been determined by quasistatic measurements, and εσ ij dielectric constants have been determined by the flat capacitor method. Experimental values of material constants have been applied for the study of Magnetostatic properties of FeSi and Fe0;98Co0;02Si single crystals have been studied. It has been found that the temperature and field dependences of the magnetization of monocrystal FeSi are strongly affected by introduction of a small amount of Co (2 %). A description of the results were provided by a model accounting for the formation of superparamagnetic iron clusters, as well as Fe-Co complexes. It is assumed that Fe-Co complexes form a ferromagnetic phase, which is approximately 0.6% of the Fe0;98Co0;02Si sample weight
В работе представлено исследование магнитостатических характеристик образцов FeSi и Fe0;98Co0;02Si. Обнаружено, что внесение небольшого количества примести Co (2 %) значительно влияет на температурные и полевые зависимости намагниченности монокристалла FeSi. Результаты обрабобтаны в рамках модели, учетывающей образование суперпарамагнитных кластеров железа, а также комплексов Fe-Co. Предполагается, что комплексы Fe-Co образуют ферромагнитную фазу, которая составляет примерно 0,6 % от массы образца Fe0;98Co0;02Si.

Читать в сети ИФ
Держатели документа:
Institute of Engineering Physics and Radioelectronics Siberian Federal University Svobodny, 79, Krasnoyarsk, 660041 Russia
Kirensky Institute of Physics Federal Research Center KSC SB RAS Akademgorodok, 50/38, Krasnoyarsk, 660036 Russia

Доп.точки доступа:
Patrin, G. S.; Патрин, Геннадий Семёнович; Yarikov, S. A.; Яриков, Станислав Алексеевич; Юркин, Глеб Юрьевич

}
Найти похожие

14.

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

15.

Dynamic remagnetisation of CoFe2O4 nanoparticles: thermal fluctuational thawing of anisotropy / D. A. Balaev, I. S. Poperechny, A. A. Krasikov [et al.] // J. Phys. D. - 2021. - Vol. 54, Is. 27. - Ст. 275003, DOI 10.1088/1361-6463/abf371. - Cited References: 63. - Experimental measurements were supported by Project No. AAAA-A17-117103050081-1. I S P and Yu L R acknowledge the support of ICMM in the framework of topical task AAAAA20-120020690030-5. The numerical calculations were performed on the Uran supercomputer (Ural Branch, Russian Academy of Sciences, Ekaterinburg) . - ISSN 0022-3727. - ISSN 1361-6463

РУБ Physics, Applied
Рубрики:
COBALT-FERRITE NANOPARTICLES
   MAGNETIC-PROPERTIES
   SIZE
   COERCIVITY
Кл.слова (ненормированные):
nanoparticles -- cobalt ferrite -- magnetodynamics -- superparamagnetism -- effective anisotropy
Аннотация: We report a study of the magnetodynamics of cobalt ferrite (CoFe2O4) nanoparticles with an average diameter of ~6 nm. Hysteresis loops were measured under quasi-static conditions and in pulse fields with amplitudes H0 of up to 130 kOe and for durations τP of 8 and 16 ms. The growth of coercivity Hc observed with an increase in the magnetic field variation rate dH/dt (determined by the values of H0 and τP) and the reduction of Hc with temperature is ascribed to the superparamagnetic effect. The proposed theoretical model explains the observed dependences fairly well. Notably, the effective magnetic anisotropy constant obtained exceeds the value for bulk crystals and might be indicative of the contribution of surface magnetic anisotropy.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
Russian Acad Sci, Inst Phys, Siberian Branch, Krasnoyarsk 660000, Russia.
Russian Acad Sci, Inst Continuous Media Mech, Ural Branch, Perm 614068, Russia.
Perm State Natl Res Univ, Dept Phase Transit Phys, Perm 614990, Russia.
Russian Acad Sci, Boreskov Inst Catalysis, Siberian Branch, Novosibirsk 630090, Russia.

Доп.точки доступа:
Balaev, D. A.; Балаев, Дмитрий Александрович; Poperechny, I. S.; Krasikov, A. A.; Красиков, Александр Александрович; Semenov, S. V.; Семёнов, Сергей Васильевич; Popkov, S. I.; Попков, Сергей Иванович; Knyazev, Yu. V.; Князев, Юрий Владимирович; Kirillov, V. L.; Yakushkin, S. S.; Martyanov, O. N.; Raikher, Y. L.; [AAAA-A17-117103050081-1]; [AAAAA20-120020690030-5]
}
Найти похожие

16.

Uncompensated magnetic moment and surface and size effects in few-nanometer antiferromagnetic NiO particles / D. A. Balaev, A. A. Krasikov, S. I. Popkov [et al.] // J. Magn. Magn. Mater. - 2021. - Vol. 539. - Ст. 168343, DOI 10.1016/j.jmmm.2021.168343. - Cited References: 98. - The TEM study was carried out on the equipment of the Krasnoyarsk Territorial Center for Collective Use, Krasnoyarsk Scientific Center, Siberian Branch, Russian Academy of Sciences . - ISSN 0304-8853
Кл.слова (ненормированные):
Antiferromagnetic NiO nanoparticles -- Uncompensated magnetic moment -- Superparamagnetism -- Surface magnetic anisotropy
Аннотация: The analysis of the M(H) magnetization curves of antiferromagnetic nanoparticles yields information about magnetic subsystems formed in these objects, which are characterized by a large fraction of surface atoms. However, in the conventionally investigated experimental magnetic field range of up to 60–90 kOe, this analysis often faces the ambiguity of distinguishing the Langevin function-simulated contribution of uncompensated magnetic moments μun of particles against the background of a linear-in-field dependence (the antiferromagnetic susceptibility and other contributions). Here, this problem has been solved using a pulsed technique, which makes it possible to significantly broaden the range of external fields in which the μun contribution approaches the saturation. Nanoparticles of a typical NiO antiferromagnet with an average size of ~ 4.5 nm have been investigated. Based on the thorough examination of the M(H) magnetization curves measured in pulsed fields of up to 250 kOe, a model of the magnetic state of NiO nanoparticles of such a small size has been proposed. The average moment is ~130 μB (μB is the Bohr magneton) per particle, which corresponds to 60–70 decompensated spins of nickel atoms localized, according to the Néel hypothesis (μun ~ 3/2), both on the surface and in the bulk of a particle. A part of the surface spins unrelated to the antiferromagnetic core form another subsystem, which behaves as free paramagnetic atoms. Along with the antiferromagnetic core, an additional linear-in-field contribution has been detected, which is apparently related to superantiferromagnetism, i.e., the size effect inherent to small antiferromagnetic particles.

Смотреть статью,
Scopus,
WOS,
Читать в сети ИФ
Держатели документа:
Kirensky Institute of Physics, Federal Research Center “Krasnoyarsk Scientific Center”, Siberian Branch, Russian Academy of Sciences, Krasnoyarsk, 660036, Russian Federation
Siberian Federal University, Krasnoyarsk, 660041, Russian Federation
Boreskov Institute of Catalysis, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090, Russian Federation

Доп.точки доступа:
Balaev, D. A.; Балаев, Дмитрий Александрович; Krasikov, A. A.; Красиков, Александр Александрович; Popkov, S. I.; Попков, Сергей Иванович; Semenov, S. V.; Семёнов, Сергей Васильевич; Volochaev, M. N.; Волочаев, Михаил Николаевич; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Kirillov, V. L.; Martyanov, O. N.
}
Найти похожие

17.

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

18.

Transport properties of FeSi with cobalt impurities / G. Y. Yurkin [et al.] // TRENDS IN MAGNETISM. - 2011. - Vol. 168-169. - P493-496, DOI 10.4028/www.scientific.net/SSP.168-169.493 . - ISSN 1012-0394
Кл.слова (ненормированные):
iron monosilicide -- kondo effect -- magnetization -- resistivity -- spindependent scattering -- superparamagnetic cluster -- cobalt -- crystals -- electric resistance -- electron energy loss spectroscopy -- kondo effect -- magnetic field effects -- magnetic properties -- magnetization -- magnetoresistance -- scattering -- superparamagnetism -- transport properties -- cobalt -- electric conductivity -- electron scattering -- impurities -- kondo effect -- magnetism -- magnetization -- experimental investigations -- kondo models -- magnetoresistance properties -- resistivity -- si crystals -- spin dependent scattering -- superparamagnetic clusters -- crystal impurities -- crystal impurities
Аннотация: The results of experimental investigations of Fe1-xCo xSi crystals in the impurity limit are presented in this article. We made an attempt to study changes of magnetic properties and conductivity in mixed Fe1-xCoxSi crystals in the impurity limit. Magnetoresistance properties are well described in the framework of Kondo model. The presence of Co-subsystem leads to the occurrence of spin-dependent channel in electron scattering conduction.

Scopus,
eLibrary,
WOS,
eLibrary
Держатели документа:
Kirensky Institute of Physics, SB, RAS, 660036, Krasnoyarsk, Russian Federation
Siberian Federal University, 660041, Krasnoyarsk, Russian Federation

Доп.точки доступа:
Yurkin, G. Yu.; Юркин, Глеб Юрьевич; Patrin, G. S.; Патрин, Геннадий Семёнович; Velikanov, D. A.; Великанов, Дмитрий Анатольевич; Beletsky, V. V.
}
Найти похожие

19.

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

20.

Maghemite nanoparticles for DNA extraction: Performance and blocking temperature / S. V. Stolyar, S. V. Komogortsev, A. S. Gorbenko [et al.] // J. Supercond. Novel Magn. - 2022. - Vol. 35, Is. 7. - P. 1929-1936, DOI 10.1007/s10948-022-06233-5. - Cited References: 33. - This work was supported by Russian Foundation for Basic Research, Government of Krasnoyarsk Territory, Krasnoyarsk Region Science and Technology Support Fund, with research projects no. 20–42-242902. We are grateful to the Center of Collective Use of FRC KSC SB RAS for the provided equipment . - ISSN 1557-1939
Кл.слова (ненормированные):
Magnetic nanoparticles -- Superparamagnetism -- Blocking temperature -- Magnetic separation
Аннотация: Iron oxide nanoparticles coated with polyethylene glycol were synthesized by coprecipitation for use in the magnetic separation of DNA (deoxyribonucleic acid). The blocking temperature of nanoparticles was studied by the methods of Mossbauer spectroscopy, ferromagnetic resonance, and using magnetometric measurements. The blocking temperature calculated from the temperature dependence of the coercive force was ~ 200 K. The calculation of the blocking temperature from the relaxation time obtained using Mossbauer spectroscopy gave a value of ~ 450 K. The blocking temperature obtained using ferromagnetic resonance was ~ 910 K. The relationship between the obtained blocking temperatures is in good agreement with the Neel-Brown formula. The constants of effective and surface anisotropy were determined by the method of ferromagnetic resonance. Isolation of DNA from blood using prepared particles and separation in a permanent magnet field revealed sufficient productivity, high speed, and the “chemical delicacy” of this approach.

Смотреть статью,
Scopus,
Читать в сети ИФ
Держатели документа:
Krasnoyarsk Scientific Center, Federal Research Center KSC SB RAS, Krasnoyarsk, Russian Federation
Kirensky Institute of Physics, Federal Research Center KSC SB RAS, Krasnoyarsk, Russian Federation
Siberian Federal University, Krasnoyarsk, Russian Federation
Ural Federal University, Ekaterinburg, Russian Federation

Доп.точки доступа:
Stolyar, S. V.; Столяр, Сергей Викторович; Komogortsev, S. V.; Комогорцев, Сергей Викторович; Gorbenko, A. S.; Knyazev, Yu. V.; Князев, Юрий Владимирович; Yaroslavtsev, R. N.; Ярославцев, Роман Николаевич; Olkhovskiy, I. A.; Neznakhin, D. S.; Tyumentseva, A. V.; Bayukov, O. A.; Баюков, Олег Артемьевич; Iskhakov, R. S.; Исхаков, Рауф Садыкович
}
Найти похожие